Comparison on the Effects and Safety of Tualang Honey and Tribestan in Sperm Parameters, Erectile Function, and Hormonal Profiles among Oligospermic Males

PubMed Central

Ismail, Shaiful Bahari; Bakar, Mohd. Bustamanizan; Nik Hussain, Nik Hazlina; Sulaiman, Siti Amrah; Jaafar, Hasnan; Draman, Samsul; Ramli, Roszaman; Wan Yusoff, Wan Zahanim

2014-01-01

Introduction. This study aims to evaluate the effectiveness of Tualang honey on sperm parameters, erectile function, and hormonal and safety profiles. Methodology. A randomized control trial was done using Tualang honey (20 grams) and Tribestan (750 mg) over a period of 12 weeks. Sperm parameters including sperm concentration, motility, and morphology were analyzed and erectile function was assessed using IIEF-5 questionnaire. Hormonal profiles of testosterone, FSH, and LH were studied. The volunteers were randomized into two groups and the outcomes were analyzed using SPSS version 18. Results. A total of 66 participants were involved. A significant increment of mean sperm concentration (P < 0.001), motility (P = 0.015) and morphology (P = 0.008) was seen in Tualang honey group. In Tribestan group, a significant increment of mean sperm concentration (P = 0.007), and morphology (P = 0.009) was seen. No significant differences of sperm concentration, motility, and morphology were seen between Tualang honey and Tribestan group and similar results were also seen in erectile function and hormonal profile. All safety profiles were normal and no adverse event was reported. Conclusion. Tualang honey effect among oligospermic males was comparable with Tribestan in improving sperm concentration, motility, and morphology. The usage of Tualang honey was also safe with no reported adverse event. PMID:25505918

Constitutive Cyclin O deficiency results in penetrant hydrocephalus, impaired growth and infertility

PubMed Central

Núnez-Ollé, Marc; Jung, Carole; Terré, Berta; Balsiger, Norman A.; Plata, Cristina; Roset, Ramon; Pardo-Pastor, Carlos; Garrido, Marta; Rojas, Santiago; Alameda, Francesc; Lloreta, Josep; Martín-Caballero, Juan; Flores, Juana M.; Stracker, Travis H.; Valverde, Miguel A.; Muñoz, Francisco J.; Gil-Gómez, Gabriel

2017-01-01

Cyclin O (encoded by CCNO) is a member of the cyclin family with regulatory functions in ciliogenesis and apoptosis. Homozygous CCNO mutations have been identified in human patients with Reduced Generation of Multiple Motile Cilia (RGMC) and conditional inactivation of Ccno in the mouse recapitulates some of the pathologies associated with the human disease. These include defects in the development of motile cilia and hydrocephalus. To further investigate the functions of Ccno in vivo, we have generated a new mouse model characterized by the constitutive loss of Ccno in all tissues and followed a cohort during ageing. Ccno-/- mice were growth impaired and developed hydrocephalus with high penetrance. In addition, some Ccno+/- mice also developed hydrocephalus and affected Ccno-/- and Ccno+/- mice exhibited additional CNS defects including cortical thinning and hippocampal abnormalities. In addition to the CNS defects, both male and female Ccno-/- mice were infertile and female mice exhibited few motile cilia in the oviduct. Our results further establish CCNO as an important gene for normal development and suggest that heterozygous CCNO mutations could underlie hydrocephalus or diminished fertility in some human patients. PMID:29245899

Constitutive Cyclin O deficiency results in penetrant hydrocephalus, impaired growth and infertility.

PubMed

Núnez-Ollé, Marc; Jung, Carole; Terré, Berta; Balsiger, Norman A; Plata, Cristina; Roset, Ramon; Pardo-Pastor, Carlos; Garrido, Marta; Rojas, Santiago; Alameda, Francesc; Lloreta, Josep; Martín-Caballero, Juan; Flores, Juana M; Stracker, Travis H; Valverde, Miguel A; Muñoz, Francisco J; Gil-Gómez, Gabriel

2017-11-21

Cyclin O (encoded by CCNO ) is a member of the cyclin family with regulatory functions in ciliogenesis and apoptosis. Homozygous CCNO mutations have been identified in human patients with Reduced Generation of Multiple Motile Cilia (RGMC) and conditional inactivation of Ccno in the mouse recapitulates some of the pathologies associated with the human disease. These include defects in the development of motile cilia and hydrocephalus. To further investigate the functions of Ccno in vivo , we have generated a new mouse model characterized by the constitutive loss of Ccno in all tissues and followed a cohort during ageing. Ccno -/- mice were growth impaired and developed hydrocephalus with high penetrance. In addition, some Ccno +/- mice also developed hydrocephalus and affected Ccno -/- and Ccno +/- mice exhibited additional CNS defects including cortical thinning and hippocampal abnormalities. In addition to the CNS defects, both male and female Ccno -/- mice were infertile and female mice exhibited few motile cilia in the oviduct. Our results further establish CCNO as an important gene for normal development and suggest that heterozygous CCNO mutations could underlie hydrocephalus or diminished fertility in some human patients.

Functional and proteomic analyses reveal that wxcB is involved in virulence, motility, detergent tolerance, and biofilm formation in Xanthomonas campestris pv. vesicatoria.

PubMed

Park, Hye-Jee; Jung, Ho Won; Han, Sang-Wook

2014-09-26

The bacterial envelope possesses diverse functions, including protection against environmental stress and virulence factors for host infection. Here, we report the function of wxcB in Xanthomonas campestris pv. vesicatoria (Xcv), a causal agent of bacterial leaf spot disease in tomato and pepper. To characterize roles of wxcB, we generated a knockout mutant (XcvΔwxcB) and found that the virulence of the mutant was weaker than that of the wild type in tomato plants. To predict the mechanism affected by wxcB, we compared protein expressions between the wild type and the mutant. Expression of 152 proteins showed a greater than 2-fold difference. Proteins involved in motility and cell wall/membrane were the most abundant. Through phenotypic assays, we further demonstrated that the mutant displayed reduced motility and tolerance to treatment, but it showed increased biofilm formation. Interestingly, the LPS profile was unchanged. These results lead to new insights into the functions of wxcB that is associated with cell wall/membrane functions, which contributes to pathogen virulence. Copyright © 2014 Elsevier Inc. All rights reserved.

Do prokaryotes contain microtubules?

NASA Technical Reports Server (NTRS)

Bermudes, D.; Hinkle, G.; Margulis, L.

1994-01-01

In eukaryotic cells, microtubules are 24-nm-diameter tubular structures composed of a class of conserved proteins called tubulin. They are involved in numerous cell functions including ciliary motility, nerve cell elongation, pigment migration, centrosome formation, and chromosome movement. Although cytoplasmic tubules and fibers have been observed in bacteria, some with diameters similar to those of eukaryotes, no homologies to eukaryotic microtubules have been established. Certain groups of bacteria including azotobacters, cyanobacteria, enteric bacteria, and spirochetes have been frequently observed to possess microtubule-like structures, and others, including archaebacteria, have been shown to be sensitive to drugs that inhibit the polymerization of microtubules. Although little biochemical or molecular biological information is available, the differences observed among these prokaryotic structures suggest that their composition generally differs among themselves as well as from that of eukaryotes. We review the distribution of cytoplasmic tubules in prokaryotes, even though, in all cases, their functions remain unknown. At least some tend to occur in cells that are large, elongate, and motile, suggesting that they may be involved in cytoskeletal functions, intracellular motility, or transport activities comparable to those performed by eukaryotic microtubules. In Escherichia coli, the FtsZ protein is associated with the formation of a ring in the division zone between the newly forming offspring cells. Like tubulin, FtsZ is a GTPase and shares with tubulin a 7-amino-acid motif, making it a promising candidate in which to seek the origin of tubulins.

Measurements of bovine sperm velocities under true anaerobic and aerobic conditions.

PubMed

Krzyzosiak, J; Molan, P; Vishwanath, R

1999-04-30

Velocities of bovine spermatozoa in a medium containing glucose were similar under true anaerobic and aerobic conditions. Spermatozoa were not able to sustain motility under anaerobic conditions when glycolysis was inhibited, but regained motility when re-aerated. This demonstrates that immobilisation was due to lack of oxygen and that conditions under which motility was analysed were truly anaerobic. Sperm motility parameters were not significantly different in the presence and absence of 4 microM antimycin A and 4 microM rotenone when glucose was present in the medium. After each incubation, functionality of sperm mitochondria was assayed by washing sperm into the medium which supported respiration but not glycolysis, and motility was visually assessed. All sperm samples were highly motile in this medium indicating that their mitochondria were functional. When glycolysis was inhibited, antimycin and rotenone abolished sperm motility immediately after addition. Bovine sperm can maintain similar levels of motility aerobically and anaerobically if a glycolysable substrate is available. Available data on bovine sperm energetics support this view.

The association between systemic sclerosis disease manifestations and esophageal high-resolution manometry parameters

PubMed Central

Kimmel, Jessica N.; Carlson, Dustin A.; Hinchcliff, Monique; Carns, Mary A.; Aren, Kathleen A; Lee, Jungwha; Pandolfino, John E.

2016-01-01

Background/Aims We aimed to evaluate the associations between SSc-related systemic manifestations and esophageal function using high-resolution manometry (HRM). Methods Patients with SSc that had undergone HRM between 1/2004 and 9/2014 were identified and HRMs were analyzed according to the Chicago Classification. Clinical characteristics were identified via retrospective chart review and compared among motility diagnoses while adjusting for age, gender, race, and SSc-disease duration. Results 79 patients (85% female, ages 25–77) were included. Clinical characteristics were compared between patients with absent contractility (AC, n = 40), ineffective esophageal motility (IEM; n = 15), and normal motility (n = 19); the 5 remaining patients met criteria for other motility diagnoses. Groups differed in severity of skin involvement measured by the modified Rodnan skin score (0–51): AC (adjusted mean 12.6), IEM (4.4), normal (4.3), p = 0.043. Pulmonary function tests [percent predicted FVC and DLCO) were lower in AC (adjusted mean, FVC: 70.3, DLCO 51.1), than IEM (FVC: 92.0; DLCO: 76.9) and normal motility (FVC: 80.0; DLCO: 67.2), p-values 0.057 (FVC) and 0.007 (DLCO). Groups did not differ by SSc-disease duration, autoantibodies, or reported symptoms of dysphagia or reflux. Conclusions In patients with SSc, absent esophageal contractility on HRM was associated with increased skin disease severity and worse lung function. Obtaining HRM to identify SSc patients with more severe esophageal dysfunction could be considered to enable implementation of management strategies in patients potentially at risk for increased morbidity and mortality. PMID:26921101

Lactotransferrin in Asian Elephant (Elephas maximus) Seminal Plasma Correlates with Semen Quality

PubMed Central

Kiso, Wendy K.; Selvaraj, Vimal; Nagashima, Jennifer; Asano, Atsushi; Brown, Janine L.; Schmitt, Dennis L.; Leszyk, John; Travis, Alexander J.; Pukazhenthi, Budhan S.

2013-01-01

Asian elephants (Elephas maximus) have highly variable ejaculate quality within individuals, greatly reducing the efficacy of artificial insemination and making it difficult to devise a sperm cryopreservation protocol for this endangered species. Because seminal plasma influences sperm function and physiology, including sperm motility, the objectives of this study were to characterize the chemistry and protein profiles of Asian elephant seminal plasma and to determine the relationships between seminal plasma components and semen quality. Ejaculates exhibiting good sperm motility (≥65%) expressed higher percentages of spermatozoa with normal morphology (80.3±13.0 vs. 44.9±30.8%) and positive Spermac staining (51.9±14.5 vs. 7.5±14.4%), in addition to higher total volume (135.1±89.6 vs. 88.8±73.1 ml) and lower sperm concentration (473.0±511.2 vs. 1313.8±764.7×106 cells ml−1) compared to ejaculates exhibiting poor sperm motility (≤10%; P<0.05). Comparison of seminal plasma from ejaculates with good versus poor sperm motility revealed significant differences in concentrations of creatine phosphokinase, alanine aminotransferase, phosphorus, sodium, chloride, magnesium, and glucose. These observations suggest seminal plasma influences semen quality in elephants. One- and two-dimensional (2D) gel electrophoresis revealed largely similar compositional profiles of seminal plasma proteins between good and poor motility ejaculates. However, a protein of ∼80 kDa was abundant in 85% of ejaculates with good motility, and was absent in 90% of poor motility ejaculates (P<0.05). We used mass spectrometry to identify this protein as lactotransferrin, and immunoblot analysis to confirm this identification. Together, these findings lay a functional foundation for understanding the contributions of seminal plasma in the regulation of Asian elephant sperm motility, and for improving semen collection and storage in this endangered species. PMID:23976974

Sodium-Hydrogen-Exchanger expression in human sperm and its relationship with semen parameters.

PubMed

Zhang, Zhe; Yang, Yuzhuo; Wu, Han; Zhang, Hongliang; Zhang, Haitao; Mao, Jiaming; Liu, Defeng; Zhao, Lianming; Lin, Haocheng; Tang, Wenhao; Hong, Kai; Jiang, Hui

2017-06-01

Sperm-specific sodium-hydrogen exchanger (sNHE) is essential to maintain sperm normal function in mice; however, its role in human sperm has not been clarified to date. The aim of this study is to investigate the expression pattern of sNHE in human spermatozoa and its relationship with sperm functional parameters. Semen samples from 68 asthenozoospermic and 61 normozoospermic men were analyzed for sperm concentration, motility, and acrosome reaction, and high motile spermatozoa were collected by swim-up method. The expression of sNHE in spermatozoa was detected by Western blot and immunofluorescence staining. The relationship between sNHE expression and sperm parameters was assessed. We identified sNHE is mainly localized to the principal piece of the human sperm tail. The expression of sNHE was positively correlated with sperm concentration, total number, and progressive motility. Moreover, sNHE expression was upregulated in swim-up sperm and associated with most of sperm motility parameters including straight line velocity and curvilinear velocity. Our results also showed that sNHE expression is decreased in sperm from patients with asthenozoospermia compared with that from normal controls. However, no correlation was found between sNHE expression and acrosome reaction in spermatozoa. The expression pattern of sNHE suggested that this protein may be involved in the regulation of sperm motility, and aberration of its expression in sperm may contribute to the pathogenesis of asthenozoospermia.

Intermediate Filaments and the Regulation of Cell Motility during Regeneration and Wound Healing.

PubMed

Cheng, Fang; Eriksson, John E

2017-09-01

SUMMARYIntermediate filaments (IFs) comprise a diverse group of flexible cytoskeletal structures, the assembly, dynamics, and functions of which are regulated by posttranslational modifications. Characteristically, the expression of IF proteins is specific for tissues, differentiation stages, cell types, and functional contexts. Recent research has rapidly expanded the knowledge of IF protein functions. From being regarded as primarily structural proteins, it is now well established that IFs act as powerful modulators of cell motility and migration, playing crucial roles in wound healing and tissue regeneration, as well as inflammatory and immune responses. Although many of these IF-associated functions are essential for tissue repair, the involvement of IF proteins has been established in many additional facets of tissue healing and regeneration. Here, we review the recent progress in understanding the multiple functions of cytoplasmic IFs that relate to cell motility in the context of wound healing, taking examples from studies on keratin, vimentin, and nestin. Wound healing and regeneration include orchestration of a broad range of cellular processes, including regulation of cell attachment and migration, proliferation, differentiation, immune responses, angiogenesis, and remodeling of the extracellular matrix. In this respect, IF proteins now emerge as multifactorial and tissue-specific integrators of tissue regeneration, thereby acting as essential guardian biopolymers at the interface between health and disease, the failing of which contributes to a diverse range of pathologies. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

FlrA, a σ54-Dependent Transcriptional Activator in Vibrio fischeri, Is Required for Motility and Symbiotic Light-Organ Colonization

PubMed Central

Millikan, Deborah S.; Ruby, Edward G.

2003-01-01

Flagellum-mediated motility of Vibrio fischeri is an essential factor in the bacterium's ability to colonize its host, the Hawaiian squid Euprymna scolopes. To begin characterizing the nature of the flagellar regulon, we have cloned a gene, designated flrA, from V. fischeri that encodes a putative σ54-dependent transcriptional activator. Genetic arrangement of the flrA locus in V. fischeri is similar to motility master-regulator operons of Vibrio cholerae and Vibrio parahaemolyticus. In addition, examination of regulatory regions of a number of flagellar operons in V. fischeri revealed apparent σ54 recognition motifs, suggesting that the flagellar regulatory hierarchy is controlled by a similar mechanism to that described in V. cholerae. However, in contrast to its closest known relatives, flrA mutant strains of V. fischeri ES114 were completely abolished in swimming capability. Although flrA provided in trans restored motility to the flrA mutant, the complemented strain was unable to reach wild-type levels of symbiotic colonization in juvenile squid, suggesting a possible role for the proper expression of FlrA in regulating symbiotic colonization factors in addition to those required for motility. Comparative RNA arbitrarily primed PCR analysis of the flrA mutant and its wild-type parent revealed several differentially expressed transcripts. These results define a regulon that includes both flagellar structural genes and other genes apparently not involved in flagellum elaboration or function. Thus, the transcriptional activator FlrA plays an essential role in regulating motility, and apparently in modulating other symbiotic functions, in V. fischeri. PMID:12775692

The tumor suppressor functions of p27(kip1) include control of the mesenchymal/amoeboid transition.

PubMed

Berton, Stefania; Belletti, Barbara; Wolf, Katarina; Canzonieri, Vincenzo; Lovat, Francesca; Vecchione, Andrea; Colombatti, Alfonso; Friedl, Peter; Baldassarre, Gustavo

2009-09-01

In many human cancers, p27 downregulation correlates with a worse prognosis, suggesting that p27 levels could represent an important determinant in cell transformation and cancer development. Using a mouse model system based on v-src-induced transformation, we show here that p27 absence is always linked to a more aggressive phenotype. When cultured in three-dimensional contexts, v-src-transformed p27-null fibroblasts undergo a morphological switch from an elongated to a rounded cell shape, accompanied by amoeboid-like morphology and motility. Importantly, the acquisition of the amoeboid motility is associated with a greater ability to move and colonize distant sites in vivo. The reintroduction of different p27 mutants in v-src-transformed p27-null cells demonstrates that the control of cell proliferation and motility represents two distinct functions of p27, both necessary for it to fully act as a tumor suppressor. Thus, we highlight here a new p27 function in driving cell plasticity that is associated with its C-terminal portion and does not depend on the control of cyclin-dependent kinase activity.

Motility Determinants in WASP Family ProteinsD⃞

PubMed Central

Yarar, Defne; D'Alessio, Joseph A.; Jeng, Robert L.; Welch, Matthew D.

2002-01-01

In response to upstream signals, proteins in the Wiskott-Aldrich Syndrome protein (WASP) family regulate actin nucleation via the Arp2/3 complex. Despite intensive study of the function of WASP family proteins in nucleation, it is not yet understood how their distinct structural organization contributes to actin-based motility. Herein, we analyzed the activities of WASP and Scar1 truncation derivatives by using a bead-based motility assay. The minimal region of WASP sufficient to direct movement was the C-terminal WCA fragment, whereas the corresponding region of Scar1 was insufficient. In addition, the proline-rich regions of WASP and Scar1 and the Ena/VASP homology 1 (EVH1) domain of WASP independently enhanced motility rates. The contributions of these regions to motility could not be accounted for by their direct effects on actin nucleation with the Arp2/3 complex, suggesting that they stimulate motility by recruiting additional factors. We have identified profilin as one such factor. WASP- and Scar1-coated bead motility rates were significantly reduced by depletion of profilin and VASP and could be more efficiently rescued by a combination of VASP and wild-type profilin than by VASP and a mutant profilin that cannot bind proline-rich sequences. Moreover, motility of WASP WCA beads was not affected by the depletion or addback of VASP and profilin. Our results suggest that recruitment of factors, including profilin, by the proline-rich regions of WASP and Scar1 and the EVH1 domain of WASP stimulates cellular actin-based motility. PMID:12429845

[Motility disorders of the esophagus].

PubMed

Bruder, E; Rougemont, A-L; Furlano, R I; Schneider, J F; Mayr, J; Haecker, F-M; Beier, K; Schneider, J; Weber, P; Berberich, T; Cathomas, G; Meier-Ruge, W A

2013-03-01

Motility disorders of the esophagus comprise a heterogeneous spectrum of diseases. Primary malformations of the esophagus are now amenable to improved surgical and gastroenterological therapies; however, they often lead to persistent long-term esophageal dysmotility. Achalasia originates from impaired relaxation of the gastroesophageal sphincter apparatus. Systemic diseases may give rise to secondary disorders of esophageal motility. A number of visceral neuromuscular disorders show an esophageal manifestation but aganglionosis rarely extends into the esophagus. The growing group of myopathies includes metabolic and mitochondrial disorders with increasing levels of genetic characterization and incipient emergence of therapeutic strategies. Esophagitis with an infectious etiology causes severe dysmotility particularly in immunocompromised patients. Immunologically mediated inflammatory processes involving the esophagus are increasingly better understood. Finally, rare tumors and tumor-like lesions may impair esophageal motor function.

NDE1 and GSK3β Associate with TRAK1 and Regulate Axonal Mitochondrial Motility: Identification of Cyclic AMP as a Novel Modulator of Axonal Mitochondrial Trafficking.

PubMed

Ogawa, Fumiaki; Murphy, Laura C; Malavasi, Elise L V; O'Sullivan, Shane T; Torrance, Helen S; Porteous, David J; Millar, J Kirsty

2016-05-18

Mitochondria are essential for neuronal function, providing the energy required to power neurotransmission, and fulfilling many important additional roles. In neurons, mitochondria must be efficiently transported to sites, including synapses, where their functions are required. Neurons, with their highly elongated morphology, are consequently extremely sensitive to defective mitochondrial trafficking which can lead to neuronal ill-health/death. We recently demonstrated that DISC1 associates with mitochondrial trafficking complexes where it associates with the core kinesin and dynein adaptor molecule TRAK1. We now show that the DISC1 interactors NDE1 and GSK3β also associate robustly with TRAK1 and demonstrate that NDE1 promotes retrograde axonal mitochondrial movement. GSK3β is known to modulate axonal mitochondrial motility, although reports of its actual effect are conflicting. We show that, in our system, GSK3β promotes anterograde mitochondrial transport. Finally, we investigated the influence of cAMP elevation upon mitochondrial motility, and found a striking increase in mitochondrial motility and retrograde movement. DISC1, NDE1, and GSK3β are implicated as risk factors for major mental illness. Our demonstration that they function together within mitochondrial trafficking complexes suggests that defective mitochondrial transport may be a contributory disease mechanism in some cases of psychiatric disorder.

Mitochondrial respiratory efficiency is positively correlated with human sperm motility.

PubMed

Ferramosca, Alessandra; Provenzano, Sara Pinto; Coppola, Lamberto; Zara, Vincenzo

2012-04-01

To correlate sperm mitochondrial respiratory efficiency with variations in sperm motility and with sperm morphologic anomalies. Sperm mitochondrial respiratory activity was evaluated with a polarographic assay of oxygen consumption carried out in hypotonically-treated sperm cells. A possible relationship among sperm mitochondrial respiratory efficiency, sperm motility, and morphologic anomalies was investigated. Mitochondrial respiratory efficiency was positively correlated with sperm motility and negatively correlated with the percentage of immotile spermatozoa. Moreover, midpiece defects impaired mitochondrial functionality. Our data indicate that an increase in sperm motility requires a parallel increase in mitochondrial respiratory capacity, thereby supporting the fundamental role played by mitochondrial oxidative phosphorylation in sperm motility of normozoospermic subjects. These results are of physiopathological relevance because they suggest that disturbances of sperm mitochondrial function and of energy production could be responsible for asthenozoospermia. Copyright © 2012 Elsevier Inc. All rights reserved.

Expression, Localization of SUMO-1, and Analyses of Potential SUMOylated Proteins in Bubalus bubalis Spermatozoa

PubMed Central

Brohi, Rahim Dad; Wang, Li; Hassine, Najla Ben; Cao, Jing; Talpur, Hira Sajjad; Wu, Di; Huang, Chun-Jie; Rehman, Zia-Ur; Bhattarai, Dinesh; Huo, Li-Jun

2017-01-01

Mature spermatozoa have highly condensed DNA that is essentially silent both transcriptionally and translationally. Therefore, post translational modifications are very important for regulating sperm motility, morphology, and for male fertility in general. Protein sumoylation was recently demonstrated in human and rodent spermatozoa, with potential consequences for sperm motility and DNA integrity. We examined the expression and localization of small ubiquitin-related modifier-1 (SUMO-1) in the sperm of water buffalo (Bubalus bubalis) using immunofluorescence analysis. We confirmed the expression of SUMO-1 in the acrosome. We further found that SUMO-1 was lost if the acrosome reaction was induced by calcium ionophore A23187. Proteins modified or conjugated by SUMO-1 in water buffalo sperm were pulled down and analyzed by mass spectrometry. Sixty proteins were identified, including proteins important for sperm morphology and motility, such as relaxin receptors and cytoskeletal proteins, including tubulin chains, actins, and dyneins. Forty-six proteins were predicted as potential sumoylation targets. The expression of SUMO-1 in the acrosome region of water buffalo sperm and the identification of potentially SUMOylated proteins important for sperm function implicates sumoylation as a crucial PTM related to sperm function. PMID:28659810

Diabetes-related dysfunction of the small intestine and the colon: focus on motility.

PubMed

Horváth, Viktor József; Putz, Zsuzsanna; Izbéki, Ferenc; Körei, Anna Erzsébet; Gerő, László; Lengyel, Csaba; Kempler, Péter; Várkonyi, Tamás

2015-11-01

In contrast to gastric dysfunction, diabetes-related functional impairments of the small and large intestine have been studied less intensively. The gastrointestinal tract accomplishes several functions, such as mixing and propulsion of luminal content, absorption and secretion of ions, water, and nutrients, defense against pathogens, and elimination of waste products. Diverse functions of the gut are regulated by complex interactions among its functional elements, including gut microbiota. The network-forming tissues, the enteric nervous system) and the interstitial cells of Cajal, are definitely impaired in diabetic patients, and their loss of function is closely related to the symptoms in diabetes, but changes of other elements could also play a role in the development of diabetes mellitus-related motility disorders. The development of our understanding over the recent years of the diabetes-induced dysfunctions in the small and large intestine are reviewed in this article.

Video Imaging and Spatiotemporal Maps to Analyze Gastrointestinal Motility in Mice.

PubMed

Swaminathan, Mathusi; Hill-Yardin, Elisa; Ellis, Melina; Zygorodimos, Matthew; Johnston, Leigh A; Gwynne, Rachel M; Bornstein, Joel C

2016-02-03

The enteric nervous system (ENS) plays an important role in regulating gastrointestinal (GI) motility and can function independently of the central nervous system. Changes in ENS function are a major cause of GI symptoms and disease and may contribute to GI symptoms reported in neuropsychiatric disorders including autism. It is well established that isolated colon segments generate spontaneous, rhythmic contractions known as Colonic Migrating Motor Complexes (CMMCs). A procedure to analyze the enteric neural regulation of CMMCs in ex vivo preparations of mouse colon is described. The colon is dissected from the animal and flushed to remove fecal content prior to being cannulated in an organ bath. Data is acquired via a video camera positioned above the organ bath and converted to high-resolution spatiotemporal maps via an in-house software package. Using this technique, baseline contractile patterns and pharmacological effects on ENS function in colon segments can be compared over 3-4 hr. In addition, propagation length and speed of CMMCs can be recorded as well as changes in gut diameter and contraction frequency. This technique is useful for characterizing gastrointestinal motility patterns in transgenic mouse models (and in other species including rat and guinea pig). In this way, pharmacologically induced changes in CMMCs are recorded in wild type mice and in the Neuroligin-3(R451C) mouse model of autism. Furthermore, this technique can be applied to other regions of the GI tract including the duodenum, jejunum and ileum and at different developmental ages in mice.

Targeting ion channels for the treatment of gastrointestinal motility disorders

PubMed Central

Beyder, Arthur

2012-01-01

Gastrointestinal (GI) functional and motility disorders are highly prevalent and responsible for long-term morbidity and sometimes mortality in the affected patients. It is estimated that one in three persons has a GI functional or motility disorder. However, diagnosis and treatment of these widespread conditions remains challenging. This partly stems from the multisystem pathophysiology, including processing abnormalities in the central and peripheral (enteric) nervous systems and motor dysfunction in the GI wall. Interstitial cells of Cajal (ICCs) are central to the generation and propagation of the cyclical electrical activity and smooth muscle cells (SMCs) are responsible for electromechanical coupling. In these and other excitable cells voltage-sensitive ion channels (VSICs) are the main molecular units that generate and regulate electrical activity. Thus, VSICs are potential targets for intervention in GI motility disorders. Research in this area has flourished with advances in the experimental methods in molecular and structural biology and electrophysiology. However, our understanding of the molecular mechanisms responsible for the complex and variable electrical behavior of ICCs and SMCs remains incomplete. In this review, we focus on the slow waves and action potentials in ICCs and SMCs. We describe the constituent VSICs, which include voltage-gated sodium (NaV), calcium (CaV), potassium (KV, KCa), chloride (Cl–) and nonselective ion channels (transient receptor potentials [TRPs]). VSICs have significant structural homology and common functional mechanisms. We outline the approaches and limitations and provide examples of targeting VSICs at the pores, voltage sensors and alternatively spliced sites. Rational drug design can come from an integrated view of the structure and mechanisms of gating and activation by voltage or mechanical stress. PMID:22282704

Neuro-ophthalmic manifestations of cerebrovascular accidents.

PubMed

Ghannam, Alaa S Bou; Subramanian, Prem S

2017-11-01

Ocular functions can be affected in almost any type of cerebrovascular accident (CVA) creating a burden on the patient and family and limiting functionality. The present review summarizes the different ocular outcomes after stroke, divided into three categories: vision, ocular motility, and visual perception. We also discuss interventions that have been proposed to help restore vision and perception after CVA. Interventions that might help expand or compensate for visual field loss and visuospatial neglect include explorative saccade training, prisms, visual restoration therapy (VRT), and transcranial direct current stimulation (tDCS). VRT makes use of neuroplasticity, which has shown efficacy in animal models but remains controversial in human studies. CVAs can lead to decreased visual acuity, visual field loss, ocular motility abnormalities, and visuospatial perception deficits. Although ocular motility problems can be corrected with surgery, vision, and perception deficits are more difficult to overcome. Interventions to restore or compensate for visual field deficits are controversial despite theoretical underpinnings, animal model evidence, and case reports of their efficacies.

Live-Cell Imaging of Phagosome Motility in Primary Mouse RPE Cells.

PubMed

Hazim, Roni; Jiang, Mei; Esteve-Rudd, Julian; Diemer, Tanja; Lopes, Vanda S; Williams, David S

2016-01-01

The retinal pigment epithelium (RPE) is a post-mitotic epithelial monolayer situated between the light-sensitive photoreceptors and the choriocapillaris. Given its vital functions for healthy vision, the RPE is a primary target for insults that result in blinding diseases, including age-related macular degeneration (AMD). One such function is the phagocytosis and digestion of shed photoreceptor outer segments. In the present study, we examined the process of trafficking of outer segment disk membranes in live cultures of primary mouse RPE, using high speed spinning disk confocal microscopy. This approach has enabled us to track phagosomes, and determine parameters of their motility, which are important for their efficient degradation.

Effects of various physical stress factors on mitochondrial function and reactive oxygen species in rat spermatozoa

PubMed Central

Kim, Suhee; Agca, Cansu; Agca, Yuksel

2013-01-01

The aim of the present study was to evaluate the effects of various physical interventions on the function of epididymal rat spermatozoa and determine whether there are correlations among these functional parameters. Epididymal rat spermatozoa were subjected to various mechanical (pipetting, centrifugation and Percoll gradient separation) and anisotonic conditions, and sperm motility, plasma membrane integrity (PMI), mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS) were evaluated. Repeated pipetting caused a loss in motility, PMI and MMP (P < 0.05). Minimal centrifugation force (200g) had no effect on motility, PMI and MMP, whereas an increase in the centrifugation force to 400g or 600g decreased sperm function (P < 0.005). Percoll gradient separation increased total motility, PMI and MMP (P < 0.05). However, the spermatozoa that were subjected to mechanical interventions showed high susceptibility to a ROS stimulant (P < 0.005). Anisotonic conditions decreased motility, PMI and MMP, and hypotonic conditions in particular increased basal ROS (P < 0.05). In correlation tests, there were strong positive correlations among total motility, PMI and MMP, whereas ROS showed no or negatively weak correlations with the other parameters. In conclusion, the physical interventions may act as important variables, affecting functional parameters of epididymal rat spermatozoa. Therefore, careful consideration and proper protocols for handling of rat spermatozoa and osmotic conditions are required to achieve reliable results and minimise damage. PMID:23140582

Human spermatozoa selected by Percoll gradient or swim-up are equally capable of binding to the human zona pellucida and undergoing the acrosome reaction.

PubMed

Morales, P; Vantman, D; Barros, C; Vigil, P

1991-03-01

Several techniques have been used for selecting motile spermatozoa including Percoll and albumin gradients, swim-up, and glass wool filtration. A high yield of motile spermatozoa as well as an enhancement of motility are the most desirable features of a practical method. An equally important consideration is whether or not these techniques select functionally normal spermatozoa. In this study we have compared two methods for separation of motile cells, swim-up and Percoll gradient. Normal semen samples from 12 different men were used in this study. Each sample was simultaneously processed by swim-up and Percoll gradient using modified Tyrode's medium. After the sperm concentration was adjusted to 1 x 10(7) spermatozoa/ml, the suspensions were incubated at 37 degrees C, 5% CO2 in air. In each suspension the percentage of sperm recovery, percentage of motile spermatozoa, percentage of acrosome reacted spermatozoa (either spontaneously or stimulated with human follicular fluid), percentage of zona-free hamster oocytes penetrated, and number of spermatozoa bound to the human zona pellucida were determined. The results obtained indicated that the percentage of sperm recovery was higher with the Percoll gradient than with the swim-up procedure (P less than 0.001). However, no significant differences were found between these two sperm populations in the percentage of motile cells, in the percentage of acrosome reacted spermatozoa, and in the percentage of zona-free hamster oocytes penetrated. In addition, the number of spermatozoa bound per zona pellucida was similar for spermatozoa selected by Percoll or swim-up. We conclude that there were no functional differences between the spermatozoa selected by either method.

Esophageal Body Motility for Clinical Assessment in Patients with Refractory Gastroesophageal Reflux Symptoms

PubMed Central

Jiang, Liuqin; Ye, Bixing; Wang, Ying; Wang, Meifeng; Lin, Lin

2017-01-01

Background/Aims Little data exists about esophageal body dysmotility and reflux patterns in refractory gastroesophageal reflux disease (RGERD) patients off therapy. We aimed to evaluate effects of esophageal body dysmotility on reflux parameters in RGERD patients by combining impedance-pH monitoring and high-resolution manometry (HRM). Methods We retrospectively reviewed the impedance-pH data and HRM metrics in patients with refractory gastroesophageal reflux symptoms. Impedance-pH monitoring and manometric data were compared between 2 groups: ineffective esophageal motility (IEM) and normal motility. Results Forty-eight patients (30 males, mean age 54.5 years) were included (16 erosive esophagitis, 24 non-erosive reflux disease, and 8 functional heartburn), amongst which 24 subjects showed IEM, and others had normal motility. Number of patients who had a large break in the IEM group was significantly higher than that of normal motility patients. IEM group had more patients with weakly acid reflux and long term acid reflux than the normal group (P = 0.008, P = 0.004, respectively). There was no statistical difference in baseine impedance levels from z4 to z6 between the 2 groups (2911 ± 1160 Ω vs 3604 ± 1232 Ω, 2766 ± 1254 Ω vs 3752 ± 1439 Ω, 2349 ± 1131 Ω vs 3038 ± 1254 Ω, all P > 0.05). Acid exposure time, numbers of long term acid reflux and weakly acid reflux showed strong negative correlation with esophageal body motility and/or lower esophageal sphincter function. Conclusions IEM was associated more with acid exposure, abnormal weakly acid reflux, and long term acid reflux in RGERD patients. These data suggested the role of esophageal body dysmotility in the pathophysiological mechanisms of RGERD patients. PMID:27599539

Esophageal Body Motility for Clinical Assessment in Patients with Refractory Gastroesophageal Reflux Symptoms.

PubMed

Jiang, Liuqin; Ye, Bixing; Wang, Ying; Wang, Meifeng; Lin, Lin

2017-01-30

Little data exists about esophageal body dysmotility and reflux patterns in refractory gastroesophageal reflux disease (RGERD) patients off therapy. We aimed to evaluate effects of esophageal body dysmotility on reflux parameters in RGERD patients by combining impedance-pH monitoring and high-resolution manometry (HRM). We retrospectively reviewed the impedance-pH data and HRM metrics in patients with refractory gastroesophageal reflux symptoms. Impedance-pH monitoring and manometric data were compared between 2 groups: ineffective esophageal motility (IEM) and normal motility. Forty-eight patients (30 males, mean age 54.5 years) were included (16 erosive esophagitis, 24 non-erosive reflux disease, and 8 functional heartburn), amongst which 24 subjects showed IEM, and others had normal motility. Number of patients who had a large break in the IEM group was significantly higher than that of normal motility patients. IEM group had more patients with weakly acid reflux and long term acid reflux than the normal group ( P = 0.008, P = 0.004, respectively). There was no statistical difference in baseine impedance levels from z4 to z6 between the 2 groups (2911 ± 1160 Ω vs 3604 ± 1232 Ω, 2766 ± 1254 Ω vs 3752 ± 1439 Ω, 2349 ± 1131 Ω vs 3038 ± 1254 Ω, all P > 0.05). Acid exposure time, numbers of long term acid reflux and weakly acid reflux showed strong negative correlation with esophageal body motility and/or lower esophageal sphincter function. IEM was associated more with acid exposure, abnormal weakly acid reflux, and long term acid reflux in RGERD patients. These data suggested the role of esophageal body dysmotility in the pathophysiological mechanisms of RGERD patients.

Azospirillum brasilense Chemotaxis Depends on Two Signaling Pathways Regulating Distinct Motility Parameters

PubMed Central

Mukherjee, Tanmoy; Kumar, Dhivya; Burriss, Nathan; Xie, Zhihong

2016-01-01

ABSTRACT The genomes of most motile bacteria encode two or more chemotaxis (Che) systems, but their functions have been characterized in only a few model systems. Azospirillum brasilense is a motile soil alphaproteobacterium able to colonize the rhizosphere of cereals. In response to an attractant, motile A. brasilense cells transiently increase swimming speed and suppress reversals. The Che1 chemotaxis pathway was previously shown to regulate changes in the swimming speed, but it has a minor role in chemotaxis and root surface colonization. Here, we show that a second chemotaxis system, named Che4, regulates the probability of swimming reversals and is the major signaling pathway for chemotaxis and wheat root surface colonization. Experimental evidence indicates that Che1 and Che4 are functionally linked to coordinate changes in the swimming motility pattern in response to attractants. The effect of Che1 on swimming speed is shown to enhance the aerotactic response of A. brasilense in gradients, likely providing the cells with a competitive advantage in the rhizosphere. Together, the results illustrate a novel mechanism by which motile bacteria utilize two chemotaxis pathways regulating distinct motility parameters to alter movement in gradients and enhance the chemotactic advantage. IMPORTANCE Chemotaxis provides motile bacteria with a competitive advantage in the colonization of diverse niches and is a function enriched in rhizosphere bacterial communities, with most species possessing at least two chemotaxis systems. Here, we identify the mechanism by which cells may derive a significant chemotactic advantage using two chemotaxis pathways that ultimately regulate distinct motility parameters. PMID:27068592

Azospirillum brasilense Chemotaxis Depends on Two Signaling Pathways Regulating Distinct Motility Parameters.

PubMed

Mukherjee, Tanmoy; Kumar, Dhivya; Burriss, Nathan; Xie, Zhihong; Alexandre, Gladys

2016-06-15

The genomes of most motile bacteria encode two or more chemotaxis (Che) systems, but their functions have been characterized in only a few model systems. Azospirillum brasilense is a motile soil alphaproteobacterium able to colonize the rhizosphere of cereals. In response to an attractant, motile A. brasilense cells transiently increase swimming speed and suppress reversals. The Che1 chemotaxis pathway was previously shown to regulate changes in the swimming speed, but it has a minor role in chemotaxis and root surface colonization. Here, we show that a second chemotaxis system, named Che4, regulates the probability of swimming reversals and is the major signaling pathway for chemotaxis and wheat root surface colonization. Experimental evidence indicates that Che1 and Che4 are functionally linked to coordinate changes in the swimming motility pattern in response to attractants. The effect of Che1 on swimming speed is shown to enhance the aerotactic response of A. brasilense in gradients, likely providing the cells with a competitive advantage in the rhizosphere. Together, the results illustrate a novel mechanism by which motile bacteria utilize two chemotaxis pathways regulating distinct motility parameters to alter movement in gradients and enhance the chemotactic advantage. Chemotaxis provides motile bacteria with a competitive advantage in the colonization of diverse niches and is a function enriched in rhizosphere bacterial communities, with most species possessing at least two chemotaxis systems. Here, we identify the mechanism by which cells may derive a significant chemotactic advantage using two chemotaxis pathways that ultimately regulate distinct motility parameters. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Motility and more: the flagellum of Trypanosoma brucei

PubMed Central

Langousis, Gerasimos; Hill, Kent L.

2014-01-01

A central feature of trypanosome cell biology and life cycle is the parasite’s single flagellum, which is an essential and multifunctional organelle involved in cell propulsion, morphogenesis and cytokinesis. The flagellar membrane is also a specialized subdomain of the cell surface that harbors multiple parasite virulence factors with roles in signaling and host-parasite interactions. In this review, we discuss the structure, assembly and function of the trypanosome flagellum, including canonical roles in cell motility as well as novel and emerging roles in cell morphogenesis and host-parasite interaction. PMID:24931043

Anatomy of Nanoscale Propulsion.

PubMed

Yadav, Vinita; Duan, Wentao; Butler, Peter J; Sen, Ayusman

2015-01-01

Nature supports multifaceted forms of life. Despite the variety and complexity of these forms, motility remains the epicenter of life. The applicable laws of physics change upon going from macroscales to microscales and nanoscales, which are characterized by low Reynolds number (Re). We discuss motion at low Re in natural and synthetic systems, along with various propulsion mechanisms, including electrophoresis, electrolyte diffusiophoresis, and nonelectrolyte diffusiophoresis. We also describe the newly uncovered phenomena of motility in non-ATP-driven self-powered enzymes and the directional movement of these enzymes in response to substrate gradients. These enzymes can also be immobilized to function as fluid pumps in response to the presence of their substrates. Finally, we review emergent collective behavior arising from interacting motile species, and we discuss the possible biomedical applications of the synthetic nanobots and microbots.

The small G-protein MglA connects to the MreB actin cytoskeleton at bacterial focal adhesions.

PubMed

Treuner-Lange, Anke; Macia, Eric; Guzzo, Mathilde; Hot, Edina; Faure, Laura M; Jakobczak, Beata; Espinosa, Leon; Alcor, Damien; Ducret, Adrien; Keilberg, Daniela; Castaing, Jean Philippe; Lacas Gervais, Sandra; Franco, Michel; Søgaard-Andersen, Lotte; Mignot, Tâm

2015-07-20

In Myxococcus xanthus the gliding motility machinery is assembled at the leading cell pole to form focal adhesions, translocated rearward to propel the cell, and disassembled at the lagging pole. We show that MglA, a Ras-like small G-protein, is an integral part of this machinery. In this function, MglA stimulates the assembly of the motility complex by directly connecting it to the MreB actin cytoskeleton. Because the nucleotide state of MglA is regulated spatially and MglA only binds MreB in the guanosine triphosphate-bound form, the motility complexes are assembled at the leading pole and dispersed at the lagging pole where the guanosine triphosphatase activating protein MglB disrupts the MglA-MreB interaction. Thus, MglA acts as a nucleotide-dependent molecular switch to regulate the motility machinery spatially. The function of MreB in motility is independent of its function in peptidoglycan synthesis, representing a coopted function. Our findings highlight a new function for the MreB cytoskeleton and suggest that G-protein-cytoskeleton interactions are a universally conserved feature. © 2015 Treuner-Lange et al.

The small G-protein MglA connects to the MreB actin cytoskeleton at bacterial focal adhesions

PubMed Central

Treuner-Lange, Anke; Macia, Eric; Guzzo, Mathilde; Hot, Edina; Faure, Laura M.; Jakobczak, Beata; Espinosa, Leon; Alcor, Damien; Ducret, Adrien; Keilberg, Daniela; Castaing, Jean Philippe; Lacas Gervais, Sandra; Franco, Michel

2015-01-01

In Myxococcus xanthus the gliding motility machinery is assembled at the leading cell pole to form focal adhesions, translocated rearward to propel the cell, and disassembled at the lagging pole. We show that MglA, a Ras-like small G-protein, is an integral part of this machinery. In this function, MglA stimulates the assembly of the motility complex by directly connecting it to the MreB actin cytoskeleton. Because the nucleotide state of MglA is regulated spatially and MglA only binds MreB in the guanosine triphosphate–bound form, the motility complexes are assembled at the leading pole and dispersed at the lagging pole where the guanosine triphosphatase activating protein MglB disrupts the MglA–MreB interaction. Thus, MglA acts as a nucleotide-dependent molecular switch to regulate the motility machinery spatially. The function of MreB in motility is independent of its function in peptidoglycan synthesis, representing a coopted function. Our findings highlight a new function for the MreB cytoskeleton and suggest that G-protein–cytoskeleton interactions are a universally conserved feature. PMID:26169353

Sperm-Associated Antigen–17 Gene Is Essential for Motile Cilia Function and Neonatal Survival

PubMed Central

Teves, Maria Eugenia; Zhang, Zhibing; Costanzo, Richard M.; Henderson, Scott C.; Corwin, Frank D.; Zweit, Jamal; Sundaresan, Gobalakrishnan; Subler, Mark; Salloum, Fadi N.; Rubin, Bruce K.

2013-01-01

Primary ciliary dyskinesia (PCD), resulting from defects in cilia assembly or motility, is caused by mutations in a number of genes encoding axonemal proteins. PCD phenotypes are variable, and include recurrent respiratory tract infections, bronchiectasis, hydrocephaly, situs inversus, and male infertility. We generated knockout mice for the sperm-associated antigen–17 (Spag17) gene, which encodes a central pair (CP) protein present in the axonemes of cells with “9 + 2” motile cilia or flagella. The targeting of Spag17 resulted in a severe phenotype characterized by immotile nasal and tracheal cilia, reduced clearance of nasal mucus, profound respiratory distress associated with lung fluid accumulation and disruption of the alveolar epithelium, cerebral ventricular expansion consistent with emerging hydrocephalus, failure to suckle, and neonatal demise within 12 hours of birth. Ultrastructural analysis revealed the loss of one CP microtubule in approximately one quarter of tracheal cilia axonemes, an absence of a C1 microtubule projection, and other less frequent CP structural abnormalities. SPAG6 and SPAG16 (CP proteins that interact with SPAG17) were increased in tracheal tissue from SPAG17-deficient mice. We conclude that Spag17 plays a critical role in the function and structure of motile cilia, and that neonatal lethality is likely explained by impaired airway mucociliary clearance. PMID:23418344

Zebrafish mutations affecting cilia motility share similar cystic phenotypes and suggest a mechanism of cyst formation that differs from pkd2 morphants

PubMed Central

Sullivan-Brown, Jessica; Schottenfeld, Jodi; Okabe, Noriko; Hostetter, Christine L.; Serluca, Fabrizio C.; Thiberge, Stephan Y.; Burdine, Rebecca D.

2008-01-01

Zebrafish are an attractive model for studying the earliest cellular defects occurring during renal cyst formation because its kidney (the pronephros) is simple and genes that cause cystic kidney diseases (CKD) in humans, cause pronephric dilations in zebrafish. By comparing phenotypes in three different mutants, locke, swt and kurly, we find that dilations occur prior to 48 hpf in the medial tubules, a location similar to where cysts form in some mammalian diseases. We demonstrate that the first observeable phenotypes associated with dilation include cilia motility and luminal remodeling defects. Importantly, we show that some phenotypes common to human CKD, such as an increased number of cells, are secondary consequences of dilation. Despite having differences in cilia motility, locke, swt and kurly share similar cystic phenotypes, suggesting that they function in a common pathway. To begin to understand the molecular mechanisms involved in cyst formation, we have cloned the swt mutation and find that it encodes a novel leucine rich repeat containing protein (LRRC50), which is thought to function in correct dynein assembly in cilia. Finally, we show that knockdown of polycystic kidney disease 2 (pkd2) specifically causes glomerular cysts and does not affect cilia motility, suggesting multiple mechanisms exist for cyst formation. PMID:18178183

Improvement of post-thawed sperm quality and fertility of Arian rooster by oral administration of d-aspartic acid.

PubMed

Ansari, Mahdi; Zhandi, Mahdi; Kohram, Hamid; Zaghari, Mojtaba; Sadeghi, Mostafa; Sharafi, Mohsen

2017-04-01

This study was conducted to investigate the effect of d-Aspartic acid (D-Asp) on post-thawed sperm quality, fertility and hatchability outcomes in male broiler breeders. Twenty 55-week-old roosters were selected and equally split into four groups (n = 5 rooster/group). Different daily D-Asp doses including 0 (D-0), 100 (D-100), 200 (D-200) or 300 (D-300) mg/kg BW were capsulated and individually administered for 12 weeks to roosters in each group. Semen samples were weekly collected from 7th to 12th week of experiment. Sperm quality from 7th to 11th week was evaluated in both fresh (total and forward motility and plasma membrane functionality) and post-thawed (total and forward motility, plasma membrane functionality, apoptosis status and mitochondrial activity) conditions. Also, collected semen samples on the 12th week were frozen and artificially inseminated to evaluate fertility and hatchability. The results from fresh condition showed that total and forward motility and plasma membrane functionality were significantly higher in D-200 compared to other groups. Also, interaction effect of time and treatment was not significant for all assessed parameters in fresh condition. In post-thawed condition, D-200 showed significantly higher total and forward motility, fertility and hatchability compared to other groups. The higher value for plasma membrane functionality and mitochondrial activity was observed in D-200 compared to D-0 and D300 groups. However, the percentage of live, early apoptotic and dead spermatozoa were not significantly affected by applied treatment in the current study. No significant difference for time and treat interaction effect was observed for all assessed parameters except forward motility. In conclusion, it seems that D-Asp administration could improve fresh and post-thawed sperm quality and post-thawed sperm fertility in male broiler breeders. Copyright © 2017 Elsevier Inc. All rights reserved.

CASA-Mot in mammals: an update.

PubMed

Yániz, J L; Silvestre, M A; Santolaria, P; Soler, C

2018-03-08

Sperm motility is one of the most widely used parameters of sperm quality. Computer-aided sperm motility analysis (CASA-Mot) systems were developed to reduce the subjectivity of sperm motility assessment, and have had broad scientific and practical acceptance. In this review, the sources of variation and current applications of this technology and its relationships with other sperm quality tests are described in detail. Despite remarkable advances in the technique, there is still great need for standardisation in many species, and the numerous factors that affect the results make it difficult to provide universally accepted criteria for classifying semen samples based on sperm motility characteristics. The main fields for CASA-Mot include the study of male fertility and pathologies, evaluation of the effects of physical and chemical agents, improvement of epidemiological survey studies, more precise calculation of seminal doses for farm animals, realisation of basic studies about sperm function, improvement of sperm technologies such as cryopreservation and quality control analysis. Numerous relationships have been established between CASA-Mot and other sperm quality tests, although most of these parameters are complementary. Future CASA-Mot systems will probably be able to integrate several sperm quality parameters with motility.

Coupling biochemistry and hydrodynamics captures hyperactivated sperm motility in a simple flagellar model

PubMed Central

Olson, Sarah D.; Suarez, Susan S.; Fauci, Lisa J.

2011-01-01

Hyperactivation in mammalian sperm is characterized by highly asymmetrical waveforms and an increase in the amplitude of flagellar bends. It is important for the sperm to be able to achieve hyperactivated motility in order to reach and fertilize the egg. Calcium (Ca2+) dynamics are known to play a large role in the initiation and maintenance of hyperactivated motility. Here we present an integrative model that couples the CatSper channel mediated Ca2+ dynamics of hyperactivation to a mechanical model of an idealized sperm flagellum in a 3-d viscous, incompressible fluid. The mechanical forces are due to passive stiffness properties and active bending moments that are a function of the local Ca2+ concentration along the length of the flagellum. By including an asymmetry in bending moments to reflect an asymmetry in the axoneme’s response to Ca2+, we capture the transition from activated motility to hyperactivated motility. We examine the effects of elastic properties of the flagellum and the Ca2+ dynamics on the overall swimming patterns. The swimming velocities of the model flagellum compare well with data for hyperactivated mouse sperm. PMID:21669209

Clinical measurement of gastrointestinal motility and function: who, when and which test?

PubMed

Fox, Mark R; Kahrilas, Peter J; Roman, Sabine; Gyawali, C Prakash; Scott, S Mark; Rao, Satish S; Keller, Jutta; Camilleri, Michael

2018-06-05

Symptoms related to abnormal gastrointestinal motility and function are common. Oropharyngeal and oesophageal dysphagia, heartburn, bloating, abdominal pain and alterations in bowel habits are among the most frequent reasons for seeking medical attention from internists or general practitioners and are also common reasons for referral to gastroenterologists and colorectal surgeons. However, the nonspecific nature of gastrointestinal symptoms, the absence of a definitive diagnosis on routine investigations (such as endoscopy, radiology or blood tests) and the lack of specific treatments make disease management challenging. Advances in technology have driven progress in the understanding of many of these conditions. This Review serves as an introduction to a series of Consensus Statements on the clinical measurements of gastrointestinal motility, function and sensitivity. A structured, evidence-based approach to the initial assessment and empirical treatment of patients presenting with gastrointestinal symptoms is discussed, followed by an outline of the contribution of modern physiological measurement on the management of patients in whom the cause of symptoms has not been identified with other tests. Discussions include the indications for and utility of high-resolution manometry, ambulatory pH-impedance monitoring, gastric emptying studies, breath tests and investigations of anorectal structure and function in day-to-day practice and clinical management.

A Biobehavioral Approach to the Treatment of Functional Encopresis in Children

ERIC Educational Resources Information Center

Friman, Patrick C.; Hofstadter, Kristi L.; Jones, Kevin M.

2006-01-01

Functional encopresis (FE) refers to the repeated passage of feces into inappropriate places at least once per month for at least 3 months. Treatment of FE targets the processes that cause or exacerbate the condition, including reduced colonic motility, constipation, and fecal impaction. The cardinal elements of successful treatment include…

Effect of breed and sperm concentration on the changes in structural, functional and motility parameters of ram-lamb spermatozoa during storage at 4 degrees C.

PubMed

Kasimanickam, Ramanathan; Kasimanickam, Vanmathy; Pelzer, Kevin D; Dascanio, John J

2007-09-01

The objectives of this study were (1) to determine the changes in structural, functional and motility parameters of ram-lamb semen stored at two different concentrations at 4 degrees C for 8 days in egg-yolk based extender and (2) to determine the effect of breed of ram-lambs on the changes in structural, functional and motility parameters of ram-lamb semen from different breeds stored at two different concentrations at 4 degrees C for 8 days in egg-yolk based extender. Two different concentrations suitable for laparoscopic and cervical insemination were employed in this experiment. A total of 14 ram-lambs (Polled Dorset-5, Suffolk-5, Katahdin-4) with satisfactory breeding potential were selected. Semen samples were collected by electro-ejaculation. Semen samples were extended to 50 and 200 million sperm per ml with a commercial egg yolk based extender (Triladyl, Minitube of America, Verona, WI, USA) at room temperature and were stored at 4 degrees C. The sperm DNA fragmentation index (DFI), percentages of high mitochondrial membrane potential (hMMP) and plasma membrane integrity (PMI) were assessed using flow cytometry as part of structural and functional parameters on Days 0, 1, 4, 6, and 8. A computer assisted sperm analyser (HTM-IVOS, Version 10.8, Hamilton Thorne Research, Beverly, MA, USA) was used to assess the sperm motility parameters on Days 0, 1, 4, 6, and 8. PROC MIXED procedure was used to determine the effect of days of storage, concentration and breed. The concentration and days of storage significantly affected the sperm structural, functional and motility parameters (P<0.0001). Significant concentration x days of storage interaction was found for all structural and functional parameters. There was a significant concentration x days of storage interaction for average path velocity, curvilinear velocity, straightness and linearity. Overall changes in the sperm structural, functional and sperm motility parameters over the storage period were less dramatic in the 200 x 10(6) ml(-1) concentration when compared to 50 x 10(6) ml(-1) concentration. The hMMP and total progressive motility were influenced by breed. In conclusion, the quality of structural, functional and motility parameters declined as days of storage were increased and the magnitude of changes in the parameters was less dramatic at the higher concentration.

Phthalate exposure and reproductive parameters in young men from the general Swedish population.

PubMed

Axelsson, Jonatan; Rylander, Lars; Rignell-Hydbom, Anna; Jönsson, Bo A G; Lindh, Christian H; Giwercman, Aleksander

2015-12-01

In animals, exposure to certain phthalates negatively affects the male reproductive function. Human results are conflicting and mostly based on subfertile males, in whom the association between exposure and reproductive function may differ from the general population. To study if levels of phthalate metabolites were associated with semen quality and reproductive hormones in general Swedish men. We recruited 314 young men delivering semen, urine and blood samples at the same visit. We analyzed reproductive hormones and several semen parameters including progressive motility and high DNA stainability (HDS)-a marker for sperm immaturity. In urine, we analyzed metabolites of phthalates, including diethylhexyl phthalate (DEHP). We studied associations between urinary levels of the metabolites and seminal as well as serum reproductive parameters, accounting for potential confounders. DEHP metabolite levels, particularly urinary mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), were negatively associated with progressive sperm motility, which was 11 (95% CI: 5.0-17) percentage points lower in the highest quartile of MECPP than in the lowest. Further, men in the highest quartile of the DEHP metabolite monoethylhexyl phthalate had 27% (95% CI: 5.5%-53%) higher HDS than men in the lowest quartile. DEHP metabolite levels seemed negatively associated with sperm motility and maturation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Systematic discovery of novel ciliary genes through functional genomics in the zebrafish

PubMed Central

Choksi, Semil P.; Babu, Deepak; Lau, Doreen; Yu, Xianwen; Roy, Sudipto

2014-01-01

Cilia are microtubule-based hair-like organelles that play many important roles in development and physiology, and are implicated in a rapidly expanding spectrum of human diseases, collectively termed ciliopathies. Primary ciliary dyskinesia (PCD), one of the most prevalent of ciliopathies, arises from abnormalities in the differentiation or motility of the motile cilia. Despite their biomedical importance, a methodical functional screen for ciliary genes has not been carried out in any vertebrate at the organismal level. We sought to systematically discover novel motile cilia genes by identifying the genes induced by Foxj1, a winged-helix transcription factor that has an evolutionarily conserved role as the master regulator of motile cilia biogenesis. Unexpectedly, we find that the majority of the Foxj1-induced genes have not been associated with cilia before. To characterize these novel putative ciliary genes, we subjected 50 randomly selected candidates to a systematic functional phenotypic screen in zebrafish embryos. Remarkably, we find that over 60% are required for ciliary differentiation or function, whereas 30% of the proteins encoded by these genes localize to motile cilia. We also show that these genes regulate the proper differentiation and beating of motile cilia. This collection of Foxj1-induced genes will be invaluable for furthering our understanding of ciliary biology, and in the identification of new mutations underlying ciliary disorders in humans. PMID:25139857

Mechanism of Actin-Based Motility

NASA Astrophysics Data System (ADS)

Pantaloni, Dominique; Le Clainche, Christophe; Carlier, Marie-France

2001-05-01

Spatially controlled polymerization of actin is at the origin of cell motility and is responsible for the formation of cellular protrusions like lamellipodia. The pathogens Listeria monocytogenes and Shigella flexneri, which undergo actin-based propulsion, are acknowledged models of the leading edge of lamellipodia. Actin-based motility of the bacteria or of functionalized microspheres can be reconstituted in vitro from only five pure proteins. Movement results from the regulated site-directed treadmilling of actin filaments, consistent with observations of actin dynamics in living motile cells and with the biochemical properties of the components of the synthetic motility medium.

Pupillary motility: bringing neuroscience to the psychiatry clinic of the future.

PubMed

Graur, Simona; Siegle, Greg

2013-08-01

Modern pupillometry has expanded the study and utility of pupil responses in many new domains, including psychiatry, particularly for understanding aspects of cognitive and emotional information processing. Here, we review the applications of pupillometry in psychiatry for understanding patients' information processing styles, predicting treatment, and augmenting function. In the past year pupillometry has been shown to be useful in specifying cognitive/affective occurrences during experimental tasks and informing clinical diagnoses. Such studies demonstrate the potential of pupillary motility to be used in clinical psychiatry much as it has been in neurology for the past century.

Antibiotic Stimulation of a Bacillus subtilis Migratory Response

PubMed Central

Liu, Yongjin; Kyle, Steven

2018-01-01

ABSTRACT Competitive interactions between bacteria reveal physiological adaptations that benefit fitness. Bacillus subtilis is a Gram-positive species with several adaptive mechanisms for competition and environmental stress. Biofilm formation, sporulation, and motility are the outcomes of widespread changes in a population of B. subtilis. These changes emerge from complex, regulated pathways for adapting to external stresses, including competition from other species. To identify competition-specific functions, we cultured B. subtilis with multiple species of Streptomyces and observed altered patterns of growth for each organism. In particular, when plated on agar medium near Streptomyces venezuelae, B. subtilis initiates a robust and reproducible mobile response. To investigate the mechanistic basis for the interaction, we determined the type of motility used by B. subtilis and isolated inducing metabolites produced by S. venezuelae. Bacillus subtilis has three defined forms of motility: swimming, swarming, and sliding. Streptomyces venezuelae induced sliding motility specifically in our experiments. The inducing agents produced by S. venezuelae were identified as chloramphenicol and a brominated derivative at subinhibitory concentrations. Upon further characterization of the mobile response, our results demonstrated that subinhibitory concentrations of chloramphenicol, erythromycin, tetracycline, and spectinomycin all activate a sliding motility response by B. subtilis. Our data are consistent with sliding motility initiating under conditions of protein translation stress. This report underscores the importance of hormesis as an early warning system for potential bacterial competitors and antibiotic exposure. IMPORTANCE Antibiotic resistance is a major challenge for the effective treatment of infectious diseases. Identifying adaptive mechanisms that bacteria use to survive low levels of antibiotic stress is important for understanding pathways to antibiotic resistance. Furthermore, little is known about the effects of individual bacterial interactions on multispecies communities. This work demonstrates that subinhibitory amounts of some antibiotics produced by streptomycetes induce active motility in B. subtilis, which may alter species interaction dynamics among species-diverse bacterial communities in natural environments. The use of antibiotics at subinhibitory concentrations results in many changes in bacteria, including changes in biofilm formation, small-colony variants, formation of persisters, and motility. Identifying the mechanistic bases of these adaptations is crucial for understanding how bacterial communities are impacted by antibiotics. PMID:29507890

Intraciliary calcium oscillations initiate vertebrate left-right asymmetry.

PubMed

Yuan, Shiaulou; Zhao, Lu; Brueckner, Martina; Sun, Zhaoxia

2015-03-02

Bilateral symmetry during vertebrate development is broken at the left-right organizer (LRO) by ciliary motility and the resultant directional flow of extracellular fluid. However, how ciliary motility is perceived and transduced into asymmetrical intracellular signaling at the LRO remains controversial. Previous work has indicated that sensory cilia and polycystin-2 (Pkd2), a cation channel, are required for sensing ciliary motility, yet their function and the molecular mechanism linking both to left-right signaling cascades are unknown. Here we report novel intraciliary calcium oscillations (ICOs) at the LRO that connect ciliary sensation of ciliary motility to downstream left-right signaling. Utilizing cilia-targeted genetically encoded calcium indicators in live zebrafish embryos, we show that ICOs depend on Pkd2 and are left-biased at the LRO in response to ciliary motility. Asymmetric ICOs occur with onset of LRO ciliary motility, thus representing the earliest known LR asymmetric molecular signal. Suppression of ICOs using a cilia-targeted calcium sink reveals that they are essential for LR development. These findings demonstrate that intraciliary calcium initiates LR development and identify cilia as a functional ion signaling compartment connecting ciliary motility and flow to molecular LR signaling. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spectrum of Clinical Diseases Caused By Disorders of Primary Cilia

PubMed Central

Aygun, Meral Gunay-; Hildebrandt, Friedhelm

2011-01-01

The ciliopathies are a category of diseases caused by disruption of the physiological functions of cilia. Ciliary dysfunction results in a broad range of phenotypes, including renal, hepatic, and pancreatic cyst formation; situs abnormalities; retinal degeneration; anosmia; cerebellar or other brain anomalies; postaxial polydactyly; bronchiectasis; and infertility. The specific clinical features are dictated by the subtype, structure, distribution, and function of the affected cilia. This review highlights the clinical variability caused by dysfunction of motile and nonmotile primary cilia and emphasizes the genetic heterogeneity and phenotypic overlap that are characteristics of these disorders. There is a need for additional research to understand the shared and unique functions of motile and nonmotile cilia and the pathophysiology resulting from mutations in cilia, basal bodies, or centrosomes. Increased understanding of ciliary biology will improve the diagnosis and management of primary ciliary dyskinesia, syndromic ciliopathies, and cilia-related cystic diseases. PMID:21926397

Assessment of basic seminal characteristics, sperm cryopreservation and heterologous in vitro fertilisation in the fishing cat (Prionailurus viverrinus).

PubMed

Thiangtum, Khongsak; Swanson, William F; Howard, JoGayle; Tunwattana, Wanchai; Tongthainan, Dakara; Wichasilpa, Wisid; Patumrattanathan, Pornchai; Pinyopoommintr, Tanu

2006-01-01

Conservation of the fishing cat, a threatened south-east Asian felid, could benefit from effective ex situ genetic management and breeding programmes, including the use of assisted reproduction. The aims of the present study were to: (1) characterise basal seminal traits of fishing cats in Thailand zoos; and (2) investigate the effect of cryopreservation on sperm motility, acrosomal integrity and in vitro function. Seminal traits were evaluated in electroejaculates collected from eight males. Spermatozoa were diluted in n-tris(hydroxymethyl)-methyl-2-aminoethanesulfonic acid Tris (TEST)-yolk buffer (TYB) without glycerol, then diluted further with TYB with glycerol (4% final concentration) at either 25 degrees C or after slow cooling to 5 degrees C and frozen in straws over liquid nitrogen vapour. After thawing, sperm function was assessed by insemination of viable domestic cat oocytes. Fishing cat ejaculates averaged (+/- s.e.m.) 43.6 +/- 14.2 x 10(6) motile spermatozoa with 33.5 +/- 6.8% normal sperm morphology. Semen processing had a negligible effect (P > 0.05) on sperm motility and acrosomal integrity, but values were reduced (P < 0.05) after thawing. All thawed samples fertilised domestic cat oocytes, with 62.1% (36/58) of mature oocytes cleaving. Glycerol addition at 5 degrees C resulted in higher (P < 0.05) post-thaw motility and intact acrosomes than glycerol addition at 25 degrees C. In conclusion, good-quality ejaculates can be obtained from Thai fishing cats and their spermatozoa exhibit adequate function after cryopreservation for in vitro fertilisation procedures.

AMP-activated kinase in human spermatozoa: identification, intracellular localization, and key function in the regulation of sperm motility.

PubMed

Calle-Guisado, Violeta; de Llera, Ana Hurtado; Martin-Hidalgo, David; Mijares, Jose; Gil, Maria C; Alvarez, Ignacio S; Bragado, Maria J; Garcia-Marin, Luis J

2017-01-01

AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This work's aims are AMPK identification, intracellular localization, and their role in human spermatozoa function. Semen was obtained from healthy human donors. Sperm AMPK and phospho-Thr172-AMPK were analyzed by Western blotting and indirect immunofluorescence. High- and low-quality sperm populations were separated by a 40%-80% density gradient. Human spermatozoa motility was evaluated by an Integrated Semen Analysis System (ISAS) in the presence or absence of the AMPK inhibitor compound C (CC). AMPK is localized along the human spermatozoa, at the entire acrosome, midpiece and tail with variable intensity, whereas its active form, phospho-Thr172-AMPK, shows a prominent staining at the acrosome and sperm tail with a weaker staining in the midpiece and the postacrosomal region. Interestingly, spermatozoa bearing an excess residual cytoplasm show strong AMPK staining in this subcellular compartment. Both AMPK and phospho-Thr172-AMPK human spermatozoa contents exhibit important individual variations. Moreover, active AMPK is predominant in the high motility sperm population, where shows a stronger intensity compared with the low motility sperm population. Inhibition of AMPK activity in human spermatozoa by CC treatment leads to a significant reduction in any sperm motility parameter analyzed: percent of motile sperm, sperm velocities, progressivity, and other motility coefficients. This work identifies and points out AMPK as a new molecular mechanism involved in human spermatozoa motility. Further AMPK implications in the clinical efficiency of assisted reproduction and in other reproductive areas need to be studied.

AMP-activated kinase in human spermatozoa: identification, intracellular localization, and key function in the regulation of sperm motility

PubMed Central

Calle-Guisado, Violeta; de Llera, Ana Hurtado; Martin-Hidalgo, David; Mijares, Jose; Gil, Maria C; Alvarez, Ignacio S; Bragado, Maria J; Garcia-Marin, Luis J

2017-01-01

AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This work's aims are AMPK identification, intracellular localization, and their role in human spermatozoa function. Semen was obtained from healthy human donors. Sperm AMPK and phospho-Thr172-AMPK were analyzed by Western blotting and indirect immunofluorescence. High- and low-quality sperm populations were separated by a 40%–80% density gradient. Human spermatozoa motility was evaluated by an Integrated Semen Analysis System (ISAS) in the presence or absence of the AMPK inhibitor compound C (CC). AMPK is localized along the human spermatozoa, at the entire acrosome, midpiece and tail with variable intensity, whereas its active form, phospho-Thr172-AMPK, shows a prominent staining at the acrosome and sperm tail with a weaker staining in the midpiece and the postacrosomal region. Interestingly, spermatozoa bearing an excess residual cytoplasm show strong AMPK staining in this subcellular compartment. Both AMPK and phospho-Thr172-AMPK human spermatozoa contents exhibit important individual variations. Moreover, active AMPK is predominant in the high motility sperm population, where shows a stronger intensity compared with the low motility sperm population. Inhibition of AMPK activity in human spermatozoa by CC treatment leads to a significant reduction in any sperm motility parameter analyzed: percent of motile sperm, sperm velocities, progressivity, and other motility coefficients. This work identifies and points out AMPK as a new molecular mechanism involved in human spermatozoa motility. Further AMPK implications in the clinical efficiency of assisted reproduction and in other reproductive areas need to be studied. PMID:27678462

Twitching motility and biofilm formation are associated with tonB1 in Xylella fastidiosa.

PubMed

Cursino, Luciana; Li, Yaxin; Zaini, Paulo A; De La Fuente, Leonardo; Hoch, Harvey C; Burr, Thomas J

2009-10-01

A mutation in the Xylella fastidiosa tonB1 gene resulted in loss of twitching motility and in significantly less biofilm formation as compared with a wild type. The altered motility and biofilm phenotypes were restored by complementation with a functional copy of the gene. The mutation affected virulence as measured by Pierce's disease symptoms on grapevines. The role of TonB1 in twitching and biofilm formation appears to be independent of the characteristic iron-uptake function of this protein. This is the first report demonstrating a functional role for a tonB homolog in X. fastidiosa.

Effects of site-directed mutagenesis of mglA on motility and swarming of Myxococcus xanthus

PubMed Central

2010-01-01

Background The mglA gene from the bacterium Myxococcus xanthus encodes a 22kDa protein related to the Ras superfamily of monomeric GTPases. MglA is required for the normal function of A-motility (adventurous), S-motility (social), fruiting body morphogenesis, and sporulation. MglA and its homologs differ from all eukaryotic and other prokaryotic GTPases because they have a threonine (Thr78) in place of the highly conserved aspartate residue of the consensus PM3 (phosphate-magnesium binding) region. To identify residues critical for MglA function or potential protein interactions, and explore the function of Thr78, the phenotypes of 18 mglA mutants were characterized. Results Nine mutants, with mutations predicted to alter residues that bind the guanine base or coordinate magnesium, did not produce detectable MglA. As expected, these mutants were mot- dev- because MglA is essential for these processes. Of the remaining nine mutants, seven showed a wild-type distribution pattern for MglA but fell into two categories with regard to function. Five of the seven mutants exhibited mild phenotypes, but two mutants, T78D and P80A, abolished motility and development. The localization pattern of MglA was abolished in two mutants that were mot- spo- and dev-. These two mutants were predicted to alter surface residues at Asp52 and Thr54, which suggests that these residues are critical for proper localization and may define a protein interaction site. Improving the consensus match with Ras at Thr78 abolished function of MglA. Only the conservative serine substitution was tolerated at this position. Merodiploid constructs revealed that a subset of alleles, including mglAD52A, were dominant and also illustrated that changing the balance of MglA and its co-transcribed partner, MglB, affects A-motility. Conclusion Our results suggest that GTP binding is critical for stability of MglA because MglA does not accumulate in mutants that cannot bind GTP. The threonine in PM3 of MglA proteins represents a novel modification of the highly conserved GTPase consensus at this position. The requirement for a hydroxyl group at this position may indicate that MglA is subject to modification under certain conditions. Proper localization of MglA is critical for both motility and development and likely involves protein interactions mediated by residues Asp52 and Thr54. PMID:21083931

Evolutionary Plasticity of AmrZ Regulation in Pseudomonas

PubMed Central

Dougherty, Kevin; Diaz, Beatriz; Murillo, Rachel

2018-01-01

ABSTRACT amrZ encodes a master regulator protein conserved across pseudomonads, which can be either a positive or negative regulator of swimming motility depending on the species examined. To better understand plasticity in the regulatory function of AmrZ, we characterized the mode of regulation for this protein for two different motility-related phenotypes in Pseudomonas stutzeri. As in Pseudomonas syringae, AmrZ functions as a positive regulator of swimming motility within P. stutzeri, which suggests that the functions of this protein with regard to swimming motility have switched at least twice across pseudomonads. Shifts in mode of regulation cannot be explained by changes in AmrZ sequence alone. We further show that AmrZ acts as a positive regulator of colony spreading within this strain and that this regulation is at least partially independent of swimming motility. Closer investigation of mechanistic shifts in dual-function regulators like AmrZ could provide unique insights into how transcriptional pathways are rewired between closely related species. IMPORTANCE Microbes often display finely tuned patterns of gene regulation across different environments, with major regulatory changes controlled by a small group of “master” regulators within each cell. AmrZ is a master regulator of gene expression across pseudomonads and can be either a positive or negative regulator for a variety of pathways depending on the strain and genomic context. Here, we demonstrate that the phenotypic outcomes of regulation of swimming motility by AmrZ have switched at least twice independently in pseudomonads, so that AmrZ promotes increased swimming motility in P. stutzeri and P. syringae but represses this phenotype in Pseudomonas fluorescens and Pseudomonas aeruginosa. Since examples of switches in regulatory mode are relatively rare, further investigation into the mechanisms underlying shifts in regulator function for AmrZ could provide unique insights into the evolution of bacterial regulatory proteins. PMID:29669886

Clinical Application of Esophageal High-resolution Manometry in the Diagnosis of Esophageal Motility Disorders.

PubMed

van Hoeij, Froukje B; Bredenoord, Albert J

2016-01-31

Esophageal high-resolution manometry (HRM) is replacing conventional manometry in the clinical evaluation of patients with esophageal symptoms, especially dysphagia. The introduction of HRM gave rise to new objective metrics and recognizable patterns of esophageal motor function, requiring a new classification scheme: the Chicago classification. HRM measurements are more detailed and more easily performed compared to conventional manometry. The visual presentation of acquired data improved the analysis and interpretation of esophageal motor function. This led to a more sensitive, accurate, and objective analysis of esophageal motility. In this review we discuss how HRM changed the way we define and categorize esophageal motility disorders. Moreover, we discuss the clinical applications of HRM for each esophageal motility disorder separately.

Clinical Application of Esophageal High-resolution Manometry in the Diagnosis of Esophageal Motility Disorders

PubMed Central

van Hoeij, Froukje B; Bredenoord, Albert J

2016-01-01

Esophageal high-resolution manometry (HRM) is replacing conventional manometry in the clinical evaluation of patients with esophageal symptoms, especially dysphagia. The introduction of HRM gave rise to new objective metrics and recognizable patterns of esophageal motor function, requiring a new classification scheme: the Chicago classification. HRM measurements are more detailed and more easily performed compared to conventional manometry. The visual presentation of acquired data improved the analysis and interpretation of esophageal motor function. This led to a more sensitive, accurate, and objective analysis of esophageal motility. In this review we discuss how HRM changed the way we define and categorize esophageal motility disorders. Moreover, we discuss the clinical applications of HRM for each esophageal motility disorder separately. PMID:26631942

Clinically relevant enhancement of human sperm motility using compounds with reported phosphodiesterase inhibitor activity

PubMed Central

Tardif, Steve; Madamidola, Oladipo A.; Brown, Sean G.; Frame, Lorna; Lefièvre, Linda; Wyatt, Paul G.; Barratt, Christopher L.R.; Martins Da Silva, Sarah J.

2014-01-01

STUDY QUESTION Can we identify compound(s) with reported phosphodiesterase inhibitor (PDEI) activity that could be added to human spermatozoa in vitro to enhance their motility without compromising other sperm functions? SUMMARY ANSWER We have identified several compounds that produce robust and effective stimulation of sperm motility and, importantly, have a positive response on patient samples. WHAT IS KNOWN ALREADY For >20 years, the use of non-selective PDEIs, such as pentoxifylline, has been known to influence the motility of human spermatozoa; however, conflicting results have been obtained. It is now clear that human sperm express several different phosphodiesterases and these are compartmentalized at different regions of the cells. By using type-specific PDEIs, differential modulation of sperm motility may be achieved without adversely affecting other functions such as the acrosome reaction (AR). STUDY DESIGN, SIZE, DURATION This was a basic medical research study examining sperm samples from normozoospermic donors and subfertile patients attending the Assisted Conception Unit (ACU), Ninewells Hospital Dundee for diagnostic semen analysis, IVF and ICSI. Phase 1 screened 43 commercially available compounds with reported PDEI activity to identify lead compounds that stimulate sperm motility. Samples were exposed (20 min) to three concentrations (1, 10 and 100 µM) of compound, and selected candidates (n = 6) progressed to Phase 2, which provided a more comprehensive assessment using a battery of in vitro sperm function tests. PARTICIPANTS/MATERIALS, SETTING, METHODS All healthy donors and subfertile patients were recruited at the Medical Research Institute, University of Dundee and ACU, Ninewells Hospital Dundee (ethical approval 08/S1402/6). In Phase 1, poor motility cells recovered from the 40% interface of the discontinuous density gradient were used as surrogates for patient samples. Pooled samples from three to four different donors were utilized in order to reduce variability and increase the number of cells available for simultaneous examination of multiple compounds. During Phase 2 testing, semen samples from 23 patients attending for either routine diagnostic andrology assessment or IVF/ICSI were prepared and exposed to selected compounds. Additionally, 48 aliquots of prepared samples, surplus to clinical use, were examined from IVF (n = 32) and ICSI (n = 16) patients to further determine the effects of selected compounds under clinical conditions of treatment. Effects of compounds on sperm motility were assessed by computer-assisted sperm analysis. A modified Kremer test using methyl cellulose was used to assess sperm functional ability to penetrate into viscous media. Sperm acrosome integrity and induction of apoptosis were assessed using the acrosomal content marker PSA-FITC and annexin V kit, respectively. MAIN RESULTS AND THE ROLE OF CHANCE In Phase 1, six compounds were found to have a strong effect on poor motility samples with a magnitude of response of ≥60% increase in percentage total motility. Under capacitating and non-capacitating conditions, these compounds significantly (P ≤ 0.05) increased the percentage of total and progressive motility. Furthermore, these compounds enhanced penetration into a cervical mucus substitute (P ≤ 0.05). Finally, the AR was not significantly induced and these compounds did not significantly increase the externalization of phosphatidylserine (P = 0.6, respectively). In general, the six compounds maintained the stimulation of motility over long periods of time (180 min) and their effects were still observed after their removal. In examinations of clinical samples, there was a general observation of a more significant stimulation of sperm motility in samples with lower baseline motility. In ICSI samples, compounds #26, #37 and #38 were the most effective at significantly increasing total motility (88, 81 and 79% of samples, respectively) and progressive motility (94, 93 and 81% of samples, respectively). In conclusion, using a two-phased drug discovery screening approach including the examination of clinical samples, 3/43 compounds were identified as promising candidates for further study. LIMITATIONS, REASONS FOR CAUTION This is an in vitro study and caution must be taken when extrapolating the results. Data for patients were from one assessment and thus the robustness of responses needs to be established. The n values for ICSI samples were relatively small. WIDER IMPLICATIONS OF THE FINDINGS We have systematically screened and identified several compounds that have robust and effective stimulation (i.e. functional significance with longevity and no toxicity) of total and progressive motility under clinical conditions of treatment. These compounds could be clinical candidates with possibilities in terms of assisted reproductive technology options for current or future patients affected by asthenozoospermia or oligoasthenozoospermia. STUDY FUNDING/COMPETING INTEREST(S) This study was funded primarily by the MRC (DPFS) but with additional funding from the Wellcome Trust, Tenovus (Scotland), University of Dundee, NHS Tayside and Scottish Enterprise. The authors have no competing interests. A patent (#WO2013054111A1) has been published containing some of the information presented in this manuscript. PMID:25124668

Concentration-dependent Sildenafil citrate (Viagra) effects on ROS production, energy status, and human sperm function.

PubMed

Sousa, Maria Inês; Amaral, Sandra; Tavares, Renata Santos; Paiva, Carla; Ramalho-Santos, João

2014-04-01

Literature regarding the effects of sildenafil citrate on sperm function remains controversial. In the present study, we specifically wanted to determine if mitochondrial dysfunction, namely membrane potential, reactive oxygen species production, and changes in energy content, are involved in in vitro sildenafil-induced alterations of human sperm function. Sperm samples of healthy men were incubated in the presence of 0.03, 0.3, and 3 μM sildenafil citrate in a phosphate buffered saline (PBS)-based medium for 2, 3, 12, and 24 hours. Sperm motility and viability were evaluated and mitochondrial function, i.e., mitochondrial membrane potential and mitochondrial superoxide production were assessed using flow-cytometry. Additionally, adenosine triphosphate (ATP) levels were determined by high performance liquid chromatography (HPLC) analysis. Results show a decrease in sperm motility correlated with the level of mitochondria-generated superoxide, without a visible effect on mitochondrial membrane potential or viability upon exposure to sildenafil. The effect on both motility and superoxide production was higher for the intermediate concentration of sildenafil (0.3 µM) indicating that the in vitro effects of sildenafil on human sperm do not vary linearly with drug concentration. Adenosine triphosphate levels also decreased following sildenafil exposure, but this decrease was only detected after a decrease in motility was already evident. These results suggest that along with the level of ATP and mitochondrial function other factors are involved in the early sildenafil-mediated decline in sperm motility. However, the further decrease in ATP levels and increase in mitochondria-generated reactive oxygen species after 24 hours of exposure might further contribute towards declining sperm motility.

Gliding Motility Revisited: How Do the Myxobacteria Move without Flagella?

PubMed Central

Mauriello, Emilia M. F.; Mignot, Tâm; Yang, Zhaomin; Zusman, David R.

2010-01-01

Summary: In bacteria, motility is important for a wide variety of biological functions such as virulence, fruiting body formation, and biofilm formation. While most bacteria move by using specialized appendages, usually external or periplasmic flagella, some bacteria use other mechanisms for their movements that are less well characterized. These mechanisms do not always exhibit obvious motility structures. Myxococcus xanthus is a motile bacterium that does not produce flagella but glides slowly over solid surfaces. How M. xanthus moves has remained a puzzle that has challenged microbiologists for over 50 years. Fortunately, recent advances in the analysis of motility mutants, bioinformatics, and protein localization have revealed likely mechanisms for the two M. xanthus motility systems. These results are summarized in this review. PMID:20508248

The Effect of Curcumin on Intracellular pH (pHi), Membrane Hyperpolarization and Sperm Motility.

PubMed

Naz, Rajesh K

2014-04-01

Curcumin has shown to affect sperm motility and function in vitro and fertility in vivo. The molecular mechanism(s) by which curcumin affects sperm motility has not been delineated. Since modulation of intracellular pH (pHi) and plasma membrane polarization is involved in sperm motility, the present study was conducted to investigate the effect of curcumin on these sperm (human and murine) parameters. The effect of curcumin on sperm forward motility was examined by counting percentages of forward moving sperm. The effect of curcumin on intracellular pH (pHi) was measured by the fluorescent pH indicator 2,7-bicarboxyethyl-5,6-carboxyfluorescein-acetoxymethyl ester (BCECF-AM). The effect of curcumin on plasma membrane polarization was examined using the fluorescence sensitive dye bis (1,3-dibarbituric acid)-trimethine oxanol [DiBAC4(3)]. Curcumin caused a concentration-dependent (p<0.05) decrease in forward motility of both human and mouse sperm. It also caused a concentration-dependent decrease in intracellular pH (pHi) in both human and mouse sperm. Curcumin induced significant (p<0.05) hyperpolarization of the plasma membrane in both human and mouse sperm. These findings indicate that curcumin inhibits sperm forward motility by intracellular acidification and hyperpolarization of sperm plasma membrane. This is the first study to our knowledge which examined the effect of curcumin on sperm pHi and membrane polarization that affect sperm forward motility. These exciting findings will have application in deciphering the signal transduction pathway involved in sperm motility and function and in development of a novel non-steroidal contraceptive for infertility.

Evidence for compromised metabolic function and limited glucose uptake in spermatozoa from the teratospermic domestic cat (Felis catus) and cheetah (Acinonyx jubatus).

PubMed

Terrell, Kimberly A; Wildt, David E; Anthony, Nicola M; Bavister, Barry D; Leibo, Stanley P; Penfold, Linda M; Marker, Laurie L; Crosier, Adrienne E

2010-11-01

Cheetahs and certain other felids consistently ejaculate high proportions (≥ 60%) of malformed spermatozoa, a condition known as teratospermia, which is prevalent in humans. Even seemingly normal spermatozoa from domestic cat teratospermic ejaculates have reduced fertilizing capacity. To understand the role of sperm metabolism in this phenomenon, we conducted a comparative study in the normospermic domestic cat versus the teratospermic cat and cheetah with the general hypothesis that sperm metabolic function is impaired in males producing predominantly pleiomorphic spermatozoa. Washed ejaculates were incubated in chemically defined medium containing glucose and pyruvate. Uptake of glucose and pyruvate and production of lactate were assessed using enzyme-linked fluorescence assays. Spermatozoa from domestic cats and cheetahs exhibited similar metabolic profiles, with minimal glucose metabolism and approximately equimolar rates of pyruvate uptake and lactate production. Compared to normospermic counterparts, pyruvate and lactate metabolism were reduced in teratospermic cat and cheetah ejaculates, even when controlling for sperm motility. Rates of pyruvate and lactate (but not glucose) metabolism were correlated positively with sperm motility, acrosomal integrity, and normal morphology. Collectively, our findings reveal that pyruvate uptake and lactate production are reliable, quantitative indicators of sperm quality in these two felid species and that metabolic function is impaired in teratospermic ejaculates. Furthermore, patterns of substrate utilization are conserved between these species, including the unexpected lack of exogenous glucose metabolism. Because glycolysis is required to support sperm motility and capacitation in certain other mammals (including dogs), the activity of this pathway in felid spermatozoa is a target for future investigation.

Ophthalmological outcome after resection of tumors based on the pineal gland.

PubMed

Hart, Michael G; Sarkies, Nicholas J; Santarius, Thomas; Kirollos, Ramez W

2013-08-01

Descriptions of visual dysfunction in pineal gland tumors tend to focus on upward gaze palsy alone. The authors aimed to characterize the nature, incidence, and functional significance of ophthalmological dysfunction after resection of tumors based on the pineal gland. Review of a retrospective case series was performed and included consecutive patients who underwent surgery performed by a consultant neurosurgeon between 2002 and 2011. Only tumors specifically based on the pineal gland were included; tumors encroaching on the pineal gland from other regions were excluded. All patients with visual signs and/or symptoms were reviewed by a specialist consultant neuroophthalmologist to accurately characterize the nature of their deficits. Visual disturbance was defined as visual symptoms caused by a disturbance of ocular motility. A total of 20 patients underwent resection of pineal gland tumors. Complete resection was obtained in 85%, and there were no perioperative deaths. Visual disturbance was present in 35% at presentation; of those who had normal ocular motility preoperatively 82% had normal motility postoperatively. In total, 55% of patients had residual visual disturbance postoperatively. Although upward gaze tended to improve, significant functional deficits remained, particularly with regard to complex convergence and accommodation dysfunction. Prisms were used in 25% but were only ever partially effective. Visual outcome was only related to preoperative visual status and tumor volume (multivariate analysis). Long-term visual morbidity after pineal gland tumor resection is common and leads to significant functional impairment. Improvement in deficits rarely occurs spontaneously, and prisms only have limited effectiveness, probably due to the dynamic nature of supranuclear ocular movement coordination.

Toxic effects of 2,4-dichlorophenoxyacetic acid on human sperm function in vitro.

PubMed

Tan, Zhengyu; Zhou, Jun; Chen, Houyang; Zou, Qianxing; Weng, Shiqi; Luo, Tao; Tang, Yuxin

2016-01-01

The herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D) is globally used in agriculture and has been linked to human sperm abnormalities in vivo. However, its effects on ejaculated human spermatozoa in vitro have not been characterized. Therefore, we examined the effects of 2,4-D on the functions of ejaculated human spermatozoa in vitro, including: sperm motility, the ability to move through a viscous medium, capacitation, and the acrosome reaction. Different doses of 2,4-D (10 nM, 100 nM, 1 µM, 10 µM, 100 µM, and 200 µM) were applied to human spermatozoa prepared from normal fresh semen samples. The results indicated that 2,4-D did not affect the viability, capacitation, or spontaneous acrosome reactions of human spermatozoa, but it dose-dependently inhibited the total motility, progressive motility, ability to penetrate viscous medium, and progesterone-induced capacitation and acrosome reaction rates. These results suggest that exposure to 2,4-D and its accumulation in the seminal plasma and follicular fluid might increase the risk of infertility. Our findings provide new insights for understanding the male reproductive toxicity of 2,4-D.

L1 stimulation of human glioma cell motility correlates with FAK activation

PubMed Central

Yang, Muhua; Li, Yupei; Chilukuri, Kalyani; Brady, Owen A.; Boulos, Magdy I.; Kappes, John C.

2011-01-01

The neural adhesion/recognition protein L1 (L1CAM; CD171) has been shown or implicated to function in stimulation of cell motility in several cancer types, including high-grade gliomas. Our previous work demonstrated the expression and function of L1 protein in stimulation of cell motility in rat glioma cells. However, the mechanism of this stimulation is still unclear. This study further investigated the function of L1 and L1 proteolysis in human glioblastoma multiforme (GBM) cell migration and invasion, as well as the mechanism of this stimulation. L1 mRNA was found to be present in human T98G GBM cell line but not in U-118 MG grade III human glioma cell line. L1 protein expression, proteolysis, and release were found in T98G cells and human surgical GBM cells by Western blotting. Exosome-like vesicles released by T98G cells were purified and contained full-length L1. In a scratch assay, T98G cells that migrated into the denuded scratch area exhibited upregulation of ADAM10 protease expression coincident with loss of surface L1. GBM surgical specimen cells exhibited a similar loss of cell surface L1 when xenografted into the chick embryo brain. When lentivirally introduced shRNA was used to attenuate L1 expression, such T98G/shL1 cells exhibited significantly decreased cell motility by time lapse microscopy in our quantitative Super Scratch assay. These cells also showed a decrease in FAK activity and exhibited increased focal complexes. L1 binding integrins which activate FAK were found in T98G and U-118 MG cells. Addition of L1 ectodomain-containing media (1) rescued the decreased cell motility of T98G/shL1 cells and (2) increased cell motility of U-118 MG cells but (3) did not further increase T98G cell motility. Injection of L1-attenuated T98G/shL1 cells into embryonic chick brains resulted in the absence of detectable invasion compared to control cells which invaded brain tissue. These studies support a mechanism where glioma cells at the edge of a cell mass upregulate ADAM10 to proteolyze surface L1 and the resultant ectodomain increases human glioma cell migration and invasion by binding to integrin receptors, activating FAK, and increasing turnover of focal complexes. PMID:21373966

L1 stimulation of human glioma cell motility correlates with FAK activation.

PubMed

Yang, Muhua; Li, Yupei; Chilukuri, Kalyani; Brady, Owen A; Boulos, Magdy I; Kappes, John C; Galileo, Deni S

2011-10-01

The neural adhesion/recognition protein L1 (L1CAM; CD171) has been shown or implicated to function in stimulation of cell motility in several cancer types, including high-grade gliomas. Our previous work demonstrated the expression and function of L1 protein in stimulation of cell motility in rat glioma cells. However, the mechanism of this stimulation is still unclear. This study further investigated the function of L1 and L1 proteolysis in human glioblastoma multiforme (GBM) cell migration and invasion, as well as the mechanism of this stimulation. L1 mRNA was found to be present in human T98G GBM cell line but not in U-118 MG grade III human glioma cell line. L1 protein expression, proteolysis, and release were found in T98G cells and human surgical GBM cells by Western blotting. Exosome-like vesicles released by T98G cells were purified and contained full-length L1. In a scratch assay, T98G cells that migrated into the denuded scratch area exhibited upregulation of ADAM10 protease expression coincident with loss of surface L1. GBM surgical specimen cells exhibited a similar loss of cell surface L1 when xenografted into the chick embryo brain. When lentivirally introduced shRNA was used to attenuate L1 expression, such T98G/shL1 cells exhibited significantly decreased cell motility by time lapse microscopy in our quantitative Super Scratch assay. These cells also showed a decrease in FAK activity and exhibited increased focal complexes. L1 binding integrins which activate FAK were found in T98G and U-118 MG cells. Addition of L1 ectodomain-containing media (1) rescued the decreased cell motility of T98G/shL1 cells and (2) increased cell motility of U-118 MG cells but (3) did not further increase T98G cell motility. Injection of L1-attenuated T98G/shL1 cells into embryonic chick brains resulted in the absence of detectable invasion compared to control cells which invaded brain tissue. These studies support a mechanism where glioma cells at the edge of a cell mass upregulate ADAM10 to proteolyze surface L1 and the resultant ectodomain increases human glioma cell migration and invasion by binding to integrin receptors, activating FAK, and increasing turnover of focal complexes.

The effect of urothelial damage on ureteric motility. An ultrastructural and functional study.

PubMed

Ugaily-Thulesius, L; Thulesius, O; Sabha, M

1988-07-01

Evidence of a leaky urothelial barrier in bilharzial uropathy is presented. The ultrastructural basis of this concept is demonstrated together with its functional consequences. The study was conducted on 4 ureters obtained at surgery from patients with non-functioning kidneys due to chronic bilharzial infections. Six normal ureters from kidney donors served as controls. Light and electron microscopic studies showed a reduced thickness of the transitional epithelium together with localised disruption of intercellular junctions and infiltration of red blood cells. The functional studies involved in vitro demonstration of stable phasic peristaltic contractions which were fundamentally altered by the addition of urine. The changes in motility included increase in contractile frequency and elevation of basal tone, inducing a state of hypermotility which could be equated with ureteric spasm. These changes were partly reversible upon administration of the histamine l-blocker, mepyramine. Evidence is presented to show that these changes might be induced in vivo by histamine released from mast cells triggered by urine leaking through a damaged urothelial barrier. The functional consequences (pain, spasm) are discussed.

How actin network dynamics control the onset of actin-based motility

PubMed Central

Kawska, Agnieszka; Carvalho, Kévin; Manzi, John; Boujemaa-Paterski, Rajaa; Blanchoin, Laurent; Martiel, Jean-Louis; Sykes, Cécile

2012-01-01

Cells use their dynamic actin network to control their mechanics and motility. These networks are made of branched actin filaments generated by the Arp2/3 complex. Here we study under which conditions the microscopic organization of branched actin networks builds up a sufficient stress to trigger sustained motility. In our experimental setup, dynamic actin networks or “gels” are grown on a hard bead in a controlled minimal protein system containing actin monomers, profilin, the Arp2/3 complex and capping protein. We vary protein concentrations and follow experimentally and through simulations the shape and mechanical properties of the actin gel growing around beads. Actin gel morphology is controlled by elementary steps including “primer” contact, growth of the network, entanglement, mechanical interaction and force production. We show that varying the biochemical orchestration of these steps can lead to the loss of network cohesion and the lack of effective force production. We propose a predictive phase diagram of actin gel fate as a function of protein concentrations. This work unveils how, in growing actin networks, a tight biochemical and physical coupling smoothens initial primer-caused heterogeneities and governs force buildup and cell motility. PMID:22908255

Electrical stimulation of gut motility guided by an in silico model

NASA Astrophysics Data System (ADS)

Barth, Bradley B.; Henriquez, Craig S.; Grill, Warren M.; Shen, Xiling

2017-12-01

Objective. Neuromodulation of the central and peripheral nervous systems is becoming increasingly important for treating a diverse set of diseases—ranging from Parkinson’s Disease and epilepsy to chronic pain. However, neuromodulation of the gastrointestinal (GI) tract has achieved relatively limited success in treating functional GI disorders, which affect a significant population, because the effects of stimulation on the enteric nervous system (ENS) and gut motility are not well understood. Here we develop an integrated neuromechanical model of the ENS and assess neurostimulation strategies for enhancing gut motility, validated by in vivo experiments. Approach. The computational model included a network of enteric neurons, smooth muscle fibers, and interstitial cells of Cajal, which regulated propulsion of a virtual pellet in a model of gut motility. Main results. Simulated extracellular stimulation of ENS-mediated motility revealed that sinusoidal current at 0.5 Hz was more effective at increasing intrinsic peristalsis and reducing colon transit time than conventional higher frequency rectangular current pulses, as commonly used for neuromodulation therapy. Further analysis of the model revealed that the 0.5 Hz sinusoidal currents were more effective at modulating the pacemaker frequency of interstitial cells of Cajal. To test the predictions of the model, we conducted in vivo electrical stimulation of the distal colon while measuring bead propulsion in awake rats. Experimental results confirmed that 0.5 Hz sinusoidal currents were more effective than higher frequency pulses at enhancing gut motility. Significance. This work demonstrates an in silico GI neuromuscular model to enable GI neuromodulation parameter optimization and suggests that low frequency sinusoidal currents may improve the efficacy of GI pacing.

Numerical Evaluation of Efficacy of Glutamate on Gastrointestinal Motility: Rapid MRI Study.

PubMed

Nakayama, Shinsuke; Teramoto, Hidemi

2016-01-01

The umami taste amino acid, glutamate acts as a signaling molecule in multiple cellular systems in the body, including the brain and gastrointestinal tract. Therefore, glutamate may affect appetite by modulating gastrointestinal motility as well as through taste perception. In this study, we examined the effect of glutamate on gastric emptying and duodenal motility, by using rapid magnetic resonance imaging (MRI). Ten healthy male volunteers participated in the measurements. Abdominal coronal MR images were successively acquired after ingestion of a liquid meal with and without monosodium L-glutamate (MSG). Image analysis was performed with a homemade segment software, in which respiratory motions were cancelled automatically by minimizing an energy function, thereby allowing participants breathe freely during MRI measurements. In two out of 10 participants, gastric emptying slowed down, while in the remaining eight participants, gastric residual volume decreased to 84% without MSG, and to 73% with MSG after 60 min. The inclusion of MSG enhanced duodenal motility, judging from changes in, 1) the magnitude of the duodenal area, 2) the center of gravity, and 3) the mean velocity of the wall motions. The third parameter most significantly indicated the excitatory effect of MSG on duodenum motility (3-7 fold increase). In conclusion, the present observations of rapid MRI indicate that MSG accelerates gastric emptying by facilitating duodenal motility, at least in healthy subjects with positive responses to MSG. This suggests the possible use of MSG as a prokinetic nutrient for improving the quality of life in hospitalized patients after a clinical assessment.

Rosiglitazone Improves Stallion Sperm Motility, ATP Content, and Mitochondrial Function.

PubMed

Swegen, Aleona; Lambourne, Sarah Renay; Aitken, R John; Gibb, Zamira

2016-11-01

Media used for equine sperm storage often contain relatively high concentrations of glucose, even though stallion spermatozoa preferentially utilize oxidative phosphorylation (OXPHOS) over glycolysis to generate ATP and support motility. Rosiglitazone is an antidiabetic compound that enhances metabolic flexibility and glucose utilization in various cell types, but its effects on sperm metabolism are unknown. This study investigated the effects of rosiglitazone on stallion sperm function in vitro, along with the possible role of AMP-activated protein kinase (AMPK) in mediating these effects. Spermatozoa were incubated with or without rosiglitazone, GW9662 (an antagonist of peroxisome proliferator-activating receptor-gamma), and compound C (CC; an AMPK inhibitor). Sperm motility, viability, reactive oxygen species production, mitochondrial membrane potential (mMP), ATP content, and glucose uptake capacity were measured. Samples incubated with rosiglitazone displayed significantly higher motility, percentage of cells with normal mMP, ATP content, and glucose uptake capacity, while sperm viability was unaffected. The percentage of spermatozoa positive for mitochondrial ROS was also significantly lower in rosiglitazone-treated samples. AMPK localized to the sperm midpiece, and its phosphorylation, was increased in rosiglitazone-treated spermatozoa. CC decreased sperm AMPK phosphorylation and reduced sperm motility, and successfully inhibited the effects of rosiglitazone. Inclusion of rosiglitazone in a room temperature sperm storage medium maintained sperm motility above 60% for 6 days, attaining significantly higher motility than sperm stored in control media. The ability of rosiglitazone to substantially alleviate the time-dependent deterioration of stallion spermatozoa by diverting metabolism away from OXPHOS and toward glycolysis has novel implications for the long-term, functional preservation of these cells. © 2016 by the Society for the Study of Reproduction, Inc.

Should I stay or should I go? Cadherin function and regulation in the neural crest

PubMed Central

Taneyhill, Lisa A.; Schiffmacher, Andrew T.

2017-01-01

Our increasing comprehension of neural crest cell development has reciprocally advanced our understanding of cadherin expression, regulation, and function. As a transient population of multipotent stem cells that significantly contribute to the vertebrate body plan, neural crest cells undergo a variety of transformative processes and exhibit many cellular behaviors, including epithelial-to-mesenchymal-transition (EMT), motility, collective cell migration, and differentiation. Multiple studies have elucidated regulatory and mechanistic details of specific cadherins during neural crest cell development in a highly contextual manner. Collectively, these results reveal that gradual changes within neural crest cells are accompanied by often times subtle, yet important, alterations in cadherin expression and function. The primary focus of this review is to coalesce recent data on cadherins in neural crest cells, from their specification to their emergence as motile cells soon after EMT, and to highlight the complexities of cadherin expression beyond our current perceptions, including the hypothesis that the neural crest EMT is a transition involving a predominantly singular cadherin switch. Further advancements in genetic approaches and molecular techniques will provide greater opportunities to integrate data from various model systems in order to distinguish unique or overlapping functions of cadherins expressed at any point throughout the ontogeny of the neural crest. PMID:28253541

Measurement of Mitochondrial Respiration and Motility in Acute Care: Sepsis, Trauma, and Poisoning.

PubMed

Jang, David H; Greenwood, John C; Spyres, Meghan B; Eckmann, David M

2017-01-01

Metabolic biomarkers have potentially wider use in disease diagnosis and prognosis as well as in monitoring disease response to treatment. While biomarkers such as interleukins, microRNA, and lactate have been proposed for disease surveillance, there are still conflicting results regarding their clinical utility. Treatment of commonly encountered disease of acute care such as sepsis, trauma, and poisoning often relies on clinical diagnosis and therapy guided by use of surrogate markers of illness severity. The measurement of mitochondrial function, including respiration and motility, may offer superior alternatives to such markers. Assessing mitochondrial function in a clinical context has the potential to impact the area of acute care in terms of diagnosis, prognosis, and treatment. The study of mitochondrial bioenergetics has become critical in understanding the pathophysiology and treatment of complex diseases such as diabetes and cardiovascular disorders. © The Author(s) 2016.

Orphan Kinesin NOD Lacks Motile Properties But Does Possess a Microtubule-stimulated ATPase Activity

PubMed Central

Matthies, Heinrich J.G.; Baskin, Ronald J.; Hawley, R. Scott

2001-01-01

NOD is a Drosophila chromosome-associated kinesin-like protein that does not fall into the chromokinesin subfamily. Although NOD lacks residues known to be critical for kinesin function, we show that microtubules activate the ATPase activity of NOD >2000-fold. Biochemical and genetic analysis of two genetically identified mutations of NOD (NODDTW and NOD“DR2”) demonstrates that this allosteric activation is critical for the function of NOD in vivo. However, several lines of evidence indicate that this ATPase activity is not coupled to vectorial transport, including 1) NOD does not produce microtubule gliding; and 2) the substitution of a single amino acid in the Drosophila kinesin heavy chain with the analogous amino acid in NOD results in a drastic inhibition of motility. We suggest that the microtubule-activated ATPase activity of NOD provides transient attachments of chromosomes to microtubules rather than producing vectorial transport. PMID:11739796

EFFECT OF SOLID MEDIUM DURING COOLED STORAGE ON STALLION SPERM PARAMETERS.

PubMed

Santos, F C; Corcini, C D; Costa, V G; Gheller, S M; Nogueira, C E; da Rosa Curcio, B; Varel, A S

2015-01-01

Solid storage medium prevents cellular sedimentation, reduces metabolic demand via limiting movement, and avoids the modification of an extender composition in the sedimentary microenvironment. It has been proven to prolong spermatozoa viability in mammalians. This experiment aims to evaluate the effect of cool storage in solid phase extender on stallion sperms. Semen was collected from 10 Crioulo stallions (n=30) and submitted to treatments: control group (semen extender) and groups with gelatin addition in different concentrations (semen extender + 1%, 2% and 3%). Seminal analyses included motility, mitochondrial functionality, plasma membrane integrity, DNA and acrosome at 0; 24; 48 and 72 hours during cooled storage at 5 degree C. Motility, mitochondrial functionality, plasma membrane and acrosome integrity declined during storage time, with no statistical difference between treatments. DNA integrity did not significantly change during storage period. Solid medium was not harmful and did not improved stallion sperm parameters during cooled storage.

[Marshmallow for investigating functional disturbances of the esophageal body].

PubMed

Keren, S; Argaman, E

1992-09-01

Manometric studies using water boluses do not always demonstrate disturbances in esophageal motility. We tested the use of a marshmallow bolus to induce abnormal manometric patterns in patients with dysphagia in whom manometric studies using water boluses were normal or nearly so. The study group included 12 normal volunteers and 22 patients with dysphagia and nearly normal manometric studies. Pressure was recorded along the esophageal body using 10 "wet" swallows followed by 10 "solid" swallows of marshmallow. In normal subjects there were fewer abnormal contractions after solid swallows than after wet swallows. In 15 patients solid swallows induced abnormal motility patterns which were not observed after wet swallows. The probability of inducing abnormal contractions in patients after solid swallows is significantly greater than after wet swallows (p < 0.0001). Solid swallowing is therefore useful in evaluating functional disturbances of the esophagus in patients with dysphagia.

Treating Woman with Myo-Inositol Vaginal Suppositories Improves Partner's Sperm Motility and Fertility.

PubMed

Montanino Oliva, Mario; Poverini, Roberta; Lisi, Rosella; Carra, Maria Cristina; Lisi, Franco

2016-01-01

Motility is the feature that allows spermatozoa to actively reach and penetrate the female gamete during fertilization. When this function is altered, and especially decreased, troubles in conceiving may occur. In this study, we demonstrated that treating fertile women with myo-inositol (MI) vaginal suppositories ameliorated their partners' sperm motility and also positively affected their conceiving capacity, without changes in cervical mucus structural and biochemical characteristics. Indeed, by means of the postcoital test on female cervical mucus, a significant improvement especially in progressive sperm motility was recorded after MI suppository use. Concomitantly, after MI treatment, a reduction of immotile spermatozoa percentage was observed. Importantly, MI vaginal supplementation positively correlated with a pregnancy for 5 of the 50 couples enrolled in the study, leading us to speculate that this substance may substantially contribute to create in the cervical mucus an ideal milieu that makes spermatozoa more motile and functionally able to fertilize. Even though the detailed mechanism is still unclear, these results should encourage MI vaginal use for the clinical improvement of male infertility, through their partners.

Treating Woman with Myo-Inositol Vaginal Suppositories Improves Partner's Sperm Motility and Fertility

PubMed Central

Poverini, Roberta; Lisi, Rosella; Carra, Maria Cristina; Lisi, Franco

2016-01-01

Motility is the feature that allows spermatozoa to actively reach and penetrate the female gamete during fertilization. When this function is altered, and especially decreased, troubles in conceiving may occur. In this study, we demonstrated that treating fertile women with myo-inositol (MI) vaginal suppositories ameliorated their partners' sperm motility and also positively affected their conceiving capacity, without changes in cervical mucus structural and biochemical characteristics. Indeed, by means of the postcoital test on female cervical mucus, a significant improvement especially in progressive sperm motility was recorded after MI suppository use. Concomitantly, after MI treatment, a reduction of immotile spermatozoa percentage was observed. Importantly, MI vaginal supplementation positively correlated with a pregnancy for 5 of the 50 couples enrolled in the study, leading us to speculate that this substance may substantially contribute to create in the cervical mucus an ideal milieu that makes spermatozoa more motile and functionally able to fertilize. Even though the detailed mechanism is still unclear, these results should encourage MI vaginal use for the clinical improvement of male infertility, through their partners. PMID:27403162

[Development of ocular motility following modified 3-wall decompression of the orbita in endocrine orbitopathy for functional and rehabilitative indication].

PubMed

Grenzebach, Ulrike H; Schnorbus, Ulrike; Büchner, Thomas; Busse, Holger; Stoll, Wolfgang

2003-05-01

Permanent visual damage due to an increase in volume of the orbital contents may be the result of the failure of conservative therapeutic concepts in the treatment of endocrine orbitopathy. Considerable progress has been achieved in developing successful orbital decompression techniques with regard to functional and cosmetic outcome. Decompression techniques with resection of the bony orbital walls are adequate tools in restoring visual acuity and reducing exophthalmus. A considerable degree of deterioration of motility disorders has been described in the literature depending on the techniques being used. The purpose of this study was to investigate whether a modified technique of 3-wall orbital decompression with preservation of a medial part of the periorbital tissue to support the medial rectus muscle, is able to reduce the postoperative risk of diplopia. A modified technique of orbital 3-wall decompression with resection of the medial orbital wall, the medial orbital floor and the floor of the frontal sinus has been used in patients with compressive optic neuropathy (n = 20) and for cosmetic reasons (n = 7) in cases of uni- or bilateral proptosis. Analysis of the results was performed concerning visual outcome, exophthalmus reduction and development of horizontal and vertical motility changes. In all cases of optic neuropathy improvement of visual function at an average of 4.63 +/- 4.5 lines could be achieved. Exophthalmus reduction was 3.2 +/- 2.4 mm in the functional group and 3.9 +/- 1.7 mm in the rehabilitative group. In this group motility of the medial rectus muscle remained unaffected except in one eye. In the functional group motility deterioration was observed in 62 %. The modified 3-wall decompression technique with preservation of a medial periorbital tissue strip is an adequate alternative technique in the therapy of optic neuropathy and exophthalmus reduction in endocrine orbitopathy with a low risk of postoperative motility disorders.

Transplantation of enteric nervous system stem cells rescues nitric oxide synthase deficient mouse colon

PubMed Central

McCann, Conor J.; Cooper, Julie E.; Natarajan, Dipa; Jevans, Benjamin; Burnett, Laura E.; Burns, Alan J.; Thapar, Nikhil

2017-01-01

Enteric nervous system neuropathy causes a wide range of severe gut motility disorders. Cell replacement of lost neurons using enteric neural stem cells (ENSC) is a possible therapy for these life-limiting disorders. Here we show rescue of gut motility after ENSC transplantation in a mouse model of human enteric neuropathy, the neuronal nitric oxide synthase (nNOS−/−) deficient mouse model, which displays slow transit in the colon. We further show that transplantation of ENSC into the colon rescues impaired colonic motility with formation of extensive networks of transplanted cells, including the development of nNOS+ neurons and subsequent restoration of nitrergic responses. Moreover, post-transplantation non-cell-autonomous mechanisms restore the numbers of interstitial cells of Cajal that are reduced in the nNOS−/− colon. These results provide the first direct evidence that ENSC transplantation can modulate the enteric neuromuscular syncytium to restore function, at the organ level, in a dysmotile gastrointestinal disease model. PMID:28671186

Effect of preoperative suggestion on postoperative gastrointestinal motility.

PubMed Central

Disbrow, E A; Bennett, H L; Owings, J T

1993-01-01

Autonomic behavior is subject to direct suggestion. We found that patients undergoing major operations benefit more from instruction than from information and reassurance. We compared the return of intestinal function after intra-abdominal operations in 2 groups of patients: the suggestion group received specific instructions for the early return of gastrointestinal motility, and the control group received an equal-length interview offering reassurance and nonspecific instructions. The suggestion group had a significantly shorter average time to the return of intestinal motility, 2.6 versus 4.1 days. Time to discharge was 6.5 versus 8.1 days. Covariates including duration of operation, amount of intraoperative bowel manipulation, and amount of postoperative narcotics were also examined using the statistical model analysis of covariance. An average savings of $1,200 per patient resulted from this simple 5-minute intervention. In summary, the use of specific physiologically active suggestions given preoperatively in a beleivable manner can reduce the morbidity associated with an intra-abdominal operation by reducing the duration of ileus. PMID:8342264

The relationship between gastrointestinal motility and gastric dilatation-volvulus in dogs.

PubMed

Gazzola, Krista M; Nelson, Laura L

2014-09-01

Gastric dilatation-volvulus (GDV) is a devastating disease that most commonly affects large and giant-breed dogs. Though a number of risk factors have been associated with the development of GDV, the etiology of GDV remains unclear. Abnormal gastric motility patterns and delayed gastric emptying have been previously described in dogs following GDV. Work evaluating the effects of gastropexy procedures and changes to gastric motility after experimental GDV has not found the same changes as those found in dogs with naturally occurring GDV. Although the role of abnormal gastric motility in dogs with GDV will need to be clarified with additional research, such study is likely to be facilitated by improved access to and development of noninvasive measurement techniques for the evaluation of gastric emptying and other motility parameters. In particular, the availability of Food and Drug Administration-approved wireless motility devices for the evaluation of gastrointestinal motility is particularly promising in the study of GDV and other functional gastrointestinal diseases of large and giant-breed dogs. Published by Elsevier Inc.

Functional proteomic analysis reveals the involvement of KIAA1199 in breast cancer growth, motility and invasiveness

PubMed Central

2014-01-01

Background KIAA1199 is a recently identified novel gene that is up-regulated in human cancer with poor survival. Our proteomic study on signaling polarity in chemotactic cells revealed KIAA1199 as a novel protein target that may be involved in cellular chemotaxis and motility. In the present study, we examined the functional significance of KIAA1199 expression in breast cancer growth, motility and invasiveness. Methods We validated the previous microarray observation by tissue microarray immunohistochemistry using a TMA slide containing 12 breast tumor tissue cores and 12 corresponding normal tissues. We performed the shRNA-mediated knockdown of KIAA1199 in MDA-MB-231 and HS578T cells to study the role of this protein in cell proliferation, migration and apoptosis in vitro. We studied the effects of KIAA1199 knockdown in vivo in two groups of mice (n = 5). We carried out the SILAC LC-MS/MS based proteomic studies on the involvement of KIAA1199 in breast cancer. Results KIAA1199 mRNA and protein was significantly overexpressed in breast tumor specimens and cell lines as compared with non-neoplastic breast tissues from large-scale microarray and studies of breast cancer cell lines and tumors. To gain deeper insights into the novel role of KIAA1199 in breast cancer, we modulated KIAA1199 expression using shRNA-mediated knockdown in two breast cancer cell lines (MDA-MB-231 and HS578T), expressing higher levels of KIAA1199. The KIAA1199 knockdown cells showed reduced motility and cell proliferation in vitro. Moreover, when the knockdown cells were injected into the mammary fat pads of female athymic nude mice, there was a significant decrease in tumor incidence and growth. In addition, quantitative proteomic analysis revealed that knockdown of KIAA1199 in breast cancer (MDA-MB-231) cells affected a broad range of cellular functions including apoptosis, metabolism and cell motility. Conclusions Our findings indicate that KIAA1199 may play an important role in breast tumor growth and invasiveness, and that it may represent a novel target for biomarker development and a novel therapeutic target for breast cancer. PMID:24628760

Motility versus fluctuations in mixtures of self-motile and passive agents.

PubMed

Hinz, Denis F; Panchenko, Alexander; Kim, Tae-Yeon; Fried, Eliot

2014-12-07

Many biological systems consist of self-motile and passive agents both of which contribute to overall functionality. However, little is known about the properties of such mixtures. Here we formulate a model for mixtures of self-motile and passive agents and show that the model gives rise to three different dynamical phases: a disordered mesoturbulent phase, a polar flocking phase, and a vortical phase characterized by large-scale counter rotating vortices. We use numerical simulations to construct a phase diagram and compare the statistical properties of the different phases with observed features of self-motile bacterial suspensions. Our findings afford specific insights regarding the interaction of microorganisms and passive particles and provide novel strategic guidance for efficient technological realizations of artificial active matter.

Cryopreservation of Iberian pig spermatozoa. Comparison of different freezing extenders based on post-thaw sperm quality.

PubMed

De Mercado, Eduardo; Rodríguez, Ana; Gómez, Emilio; Sanz, Elena

2010-03-01

The aim of this study was to evaluate the cryoprotective effect of different freezing extenders against cryopreservation injuries on Iberian boar sperm. The sperm-rich fraction was collected and pooled from six sexually mature Iberian boars, and was frozen in different extenders containing glucose, lactose or fructose as sugar source and including Orvus ES Paste only in the freezing extender-2 (Glucose; Lactose and Fructose) or in both freezing extenders (Glucose2; Lactose2 and Fructose2). During the cryopreservation process, the supernatant was removed after the centrifugation step, then was extended with freezing extender-1 for the equilibration period and with freezing extender-2 immediately before freezing. Post-thaw sperm characteristics, such as plasma membrane integrity (SYBR-14/PI), mitochondrial function (Rhodamine 123) and acrosome integrity (NAR), were monitored. Overall sperm motility and the individual kinematic parameters of motile spermatozoa (assessed by the computer-aided sperm analysis system Sperm Class Analyzer [SCA]) were recorded in the different experimental treatments. Measurements were taken at 30 and 150 min post-thaw. The state of the acrosome after thawing did not show significant differences between the freezing extenders studied. Freezing-thawing caused a significant decrease (P<0.001) in plasma membrane integrity and in mitochondrial activity in the spermatozoa frozen with Orvus ES Paste in both freezing extenders. Furthermore, spermatozoa frozen with Orvus ES Paste in both freezing extenders exhibited lower (P<0.05) motility and kinematic parameters than those frozen in the absence of Orvus ES Paste in the first freezing extender. The spermatozoa frozen with the Lactose extender and with Orvus ES Paste only in the second freezing extender showed a better evolution of the motility and kinematic characteristics (P<0.05) over time. The deterioration in post-thaw sperm motility and kinematic parameters were concurrent with reduced sperm characteristics. It can be suggested that in the Iberian pig, the beneficial effects of Orvus ES Paste during the freezing process of spermatozoa is time dependent. The analysis of different sperm characteristics such as motility, plasma membrane integrity and mitochondrial function, determined that the extenders studied in the present experiment affected the quality of frozen-thawed semen in Iberian boar.

Diversification of caldesmon-linked actin cytoskeleton in cell motility

PubMed Central

Mayanagi, Taira

2011-01-01

The actin cytoskeleton plays a key role in regulating cell motility. Caldesmon (CaD) is an actin-linked regulatory protein found in smooth muscle and non-muscle cells that is conserved among a variety of vertebrates. It binds and stabilizes actin filaments, as well as regulating actin-myosin interaction in a calcium (Ca2+)/calmodulin (CaM)- and/or phosphorylation-dependent manner. CaD function is regulated qualitatively by Ca2+/CaM and by its phosphorylation state and quantitatively at the mRNA level, by three different transcriptional regulation of the CALD1 gene. CaD has numerous functions in cell motility, such as migration, invasion and proliferation, exerted via the reorganization of the actin cytoskeleton. Here we will outline recent findings regarding CaD's structural features and functions. PMID:21350330

Effect of Daily Supine LBNP Exercise on Gastrointestinal Motility During Antiorthostatic Bedrest in Normal Subjects

NASA Technical Reports Server (NTRS)

Putcha, Lakshmi; DeKerlegand, D.; Hargens, Alan R. (Technical Monitor)

1997-01-01

Space flight alters gastrointestinal (GI) function in general, and GI motility, in particular. This can decrease appetite, affect the body's ability to absorb nutrients, fluids and electrolytes, and contribute to a negative energy balance. Antiorthostatic bed rest (ABR) has been used to simulate microgravity-induced physiological changes in human subjects. The objective of this investigation is to determine if daily supine lower body negative pressure (LBNP) exercise will maintain GI motility at near normal levels during ABR. Eight subjects participated in the study protocol consisting of an ambulatory phase scheduled before bedrest periods and two 14 day bed rest (6 deg head-down tilt) periods, once with and another time without exercise. Supine treadmill running in an LBNP chamber was used for exercise. Mouth-to-cecum transit time (MCTT) of lactulose was measured indirectly using the rise in breath hydrogen level after oral administration of lactulose (20 g) following a standard low-fiber breakfast. GI motility during ambulatory and ABR periods was assessed using MCTT data. Results of this Study indicate that GI motility during ABR without exercise decreased by 45% [MCTT +/- S.E.M. 56.2 +/- 6.0 (Ambulatory); 87.3 +/- 8.3 (ABR)]. Supine LBNP exercise did not significantly alter this reduction in GI motility during ABR [MCTT +/- S.E.M. 81.3 +/- 4.2 (Exercise); 87.3 +/- 8.3 (No Exercise)]. These results suggest that supine LBNP exercise may not be an effective countermeasure for microgravity-induced decrements in GI motility and function.

Computational approaches to substrate-based cell motility

DOE PAGES

Ziebert, Falko; Aranson, Igor S.

2016-07-15

Substrate-based crawling motility of eukaryotic cells is essential for many biological functions, both in developing and mature organisms. Motility dysfunctions are involved in several life-threatening pathologies such as cancer and metastasis. Motile cells are also a natural realization of active, self-propelled ‘particles’, a popular research topic in nonequilibrium physics. Finally, from the materials perspective, assemblies of motile cells and evolving tissues constitute a class of adaptive self-healing materials that respond to the topography, elasticity, and surface chemistry of the environment and react to external stimuli. Although a comprehensive understanding of substrate-based cell motility remains elusive, progress has been achieved recentlymore » in its modeling on the whole cell level. Furthermore we survey the most recent advances in computational approaches to cell movement and demonstrate how these models improve our understanding of complex self-organized systems such as living cells.« less

Inactivation of pecS restores the virulence of mutants devoid of osmoregulated periplasmic glucans in the phytopathogenic bacterium Dickeya dadantii.

PubMed

Bontemps-Gallo, Sébastien; Madec, Edwige; Lacroix, Jean-Marie

2014-04-01

Dickeya dadantii is a phytopathogenic enterobacterium that causes soft rot disease in a wide range of plant species. Maceration, an apparent symptom of the disease, is the result of the synthesis and secretion of a set of plant cell wall-degrading enzymes (PCWDEs), but many additional factors are required for full virulence. Among these, osmoregulated periplasmic glucans (OPGs) and the PecS transcriptional regulator are essential virulence factors. Several cellular functions are controlled by both OPGs and PecS. Strains devoid of OPGs display a pleiotropic phenotype including total loss of virulence, loss of motility and severe reduction in the synthesis of PCWDEs. PecS is one of the major regulators of virulence in D. dadantii, acting mainly as a repressor of various cellular functions including virulence, motility and synthesis of PCWDEs. The present study shows that inactivation of the pecS gene restored virulence in a D. dadantii strain devoid of OPGs, indicating that PecS cannot be de-repressed in strains devoid of OPGs.

Motility Disorders in Children.

PubMed

Nurko, Samuel

2017-06-01

Gastrointestinal motility disorders in the pediatric population are common and can range from benign processes to more serious disorders. Performing and interpreting motility evaluations in children present unique challenges. There are primary motility disorders but abnormal motility may be secondary due to other disease processes. Diagnostic studies include radiographic scintigraphic and manometry studies. Although recent advances in the genetics, biology, and technical aspects are having an important impact and have allowed for a better understanding of the pathophysiology and therapy for gastrointestinal motility disorders in children, further research is needed to be done to have better understanding of the pathophysiology and for better therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

Software-assisted small bowel motility analysis using free-breathing MRI: feasibility study.

PubMed

Bickelhaupt, Sebastian; Froehlich, Johannes M; Cattin, Roger; Raible, Stephan; Bouquet, Hanspeter; Bill, Urs; Patak, Michael A

2014-01-01

To validate a software prototype allowing for small bowel motility analysis in free breathing by comparing it to manual measurements. In all, 25 patients (15 male, 10 female; mean age 39 years) were included in this Institutional Review Board-approved, retrospective study. Magnetic resonance imaging (MRI) was performed on a 1.5T system after standardized preparation acquiring motility sequences in free breathing over 69-84 seconds. Small bowel motility was analyzed manually and with the software. Functional parameters, measurement time, and reproducibility were compared using the coefficient of variance and paired Student's t-test. Correlation was analyzed using Pearson's correlation coefficient and linear regression. The 25 segments were analyzed twice both by hand and using the software with automatic breathing correction. All assessed parameters significantly correlated between the methods (P < 0.01), but the scattering of repeated measurements was significantly (P < 0.01) lower using the software (3.90%, standard deviation [SD] ± 5.69) than manual examinations (9.77%, SD ± 11.08). The time needed was significantly less (P < 0.001) with the software (4.52 minutes, SD ± 1.58) compared to manual measurement, lasting 17.48 minutes for manual (SD ± 1.75 minutes). The use of the software proves reliable and faster small bowel motility measurements in free-breathing MRI compared to manual analyses. The new technique allows for analyses of prolonged sequences acquired in free breathing, improving the informative value of the examinations by amplifying the evaluable data. Copyright © 2013 Wiley Periodicals, Inc.

Effect of dilution in sperm maturation media and time of storage on sperm motility and fertilizing capacity of cryopreserved semen of sex-reversed female rainbow trout.

PubMed

Judycka, Sylwia; Ciereszko, Andrzej; Dobosz, Stefan; Zalewski, Tomasz; Dietrich, Grzegorz J

2017-05-01

Masculinized females, also called neomales or sex-reversed females have a male phenotype but retain the female genotype (XX). Therefore, all spermatozoa produced in their functional testes carry an X chromosome, which is desired for the production of all-female rainbow trout populations. Semen of sex-reversed female rainbow trout is of low quality and in vitro maturation is required, which includes dilution of sperm suspensions with specially formulated maturation solutions. The aim of this study was to determine the effect of dilution in different maturation media on sperm quality (sperm motility characteristics and fertilizing capacity) of frozen/thawed sperm of sex-reversed female rainbow trout. The effect of time of post-thaw storage (0, 15, 60 and 120min) on semen quality was also tested. Sperm motility parameters and fertilization rate at the eyed and hatching stages were assessed for post-thaw semen diluted in different media. The cryopreservation procedure resulted in high post-thaw sperm motility of about 57% and did not differ from fresh semen. Unexpectedly, maturation media decreased sperm activation capacity immediately after dilution; however, sperm motility increased over time. Fertilization rates of frozen/thawed semen were high (71-87%) and did not differ significantly between experimental variants at any of tested periods of storage. Our results demonstrated that the effect of the maturation media on frozen/thawed sperm is different from that of fresh sperm. The progressive increase in post-thaw sperm motility in maturation media can potentially be applied to routine hatchery practice. Copyright © 2016 Elsevier Inc. All rights reserved.

Coordinated Cyclic-Di-GMP Repression of Salmonella Motility through YcgR and Cellulose

PubMed Central

Zorraquino, Violeta; García, Begoña; Latasa, Cristina; Echeverz, Maite; Toledo-Arana, Alejandro; Valle, Jaione

2013-01-01

Cyclic di-GMP (c-di-GMP) is a secondary messenger that controls a variety of cellular processes, including the switch between a biofilm and a planktonic bacterial lifestyle. This nucleotide binds to cellular effectors in order to exert its regulatory functions. In Salmonella, two proteins, BcsA and YcgR, both of them containing a c-di-GMP binding PilZ domain, are the only known c-di-GMP receptors. BcsA, upon c-di-GMP binding, synthesizes cellulose, the main exopolysaccharide of the biofilm matrix. YcgR is dedicated to c-di-GMP-dependent inhibition of motility through its interaction with flagellar motor proteins. However, previous evidences indicate that in the absence of YcgR, there is still an additional element that mediates motility impairment under high c-di-GMP levels. Here we have uncovered that cellulose per se is the factor that further promotes inhibition of bacterial motility once high c-di-GMP contents drive the activation of a sessile lifestyle. Inactivation of different genes of the bcsABZC operon, mutation of the conserved residues in the RxxxR motif of the BcsA PilZ domain, or degradation of the cellulose produced by BcsA rescued the motility defect of ΔycgR strains in which high c-di-GMP levels were reached through the overexpression of diguanylate cyclases. High c-di-GMP levels provoked cellulose accumulation around cells that impeded flagellar rotation, probably by means of steric hindrance, without affecting flagellum gene expression, exportation, or assembly. Our results highlight the relevance of cellulose in Salmonella lifestyle switching as an architectural element that is both essential for biofilm development and required, in collaboration with YcgR, for complete motility inhibition. PMID:23161026

Engineering bacterial motility towards hydrogen-peroxide.

PubMed

Virgile, Chelsea; Hauk, Pricila; Wu, Hsuan-Chen; Shang, Wu; Tsao, Chen-Yu; Payne, Gregory F; Bentley, William E

2018-01-01

Synthetic biologists construct innovative genetic/biological systems to treat environmental, energy, and health problems. Many systems employ rewired cells for non-native product synthesis, while a few have employed the rewired cells as 'smart' devices with programmable function. Building on the latter, we developed a genetic construct to control and direct bacterial motility towards hydrogen peroxide, one of the body's immune response signaling molecules. A motivation for this work is the creation of cells that can target and autonomously treat disease, the latter signaled by hydrogen peroxide release. Bacteria naturally move towards a variety of molecular cues (e.g., nutrients) in the process of chemotaxis. In this work, we engineered bacteria to recognize and move towards hydrogen peroxide, a non-native chemoattractant and potential toxin. Our system exploits oxyRS, the native oxidative stress regulon of E. coli. We first demonstrated H2O2-mediated upregulation motility regulator, CheZ. Using transwell assays, we showed a two-fold increase in net motility towards H2O2. Then, using a 2D cell tracking system, we quantified bacterial motility descriptors including velocity, % running (of tumble/run motions), and a dynamic net directionality towards the molecular cue. In CheZ mutants, we found that increased H2O2 concentration (0-200 μM) and induction time resulted in increased running speeds, ultimately reaching the native E. coli wild-type speed of ~22 μm/s with a ~45-65% ratio of running to tumbling. Finally, using a microfluidic device with stable H2O2 gradients, we characterized responses and the potential for "programmed" directionality towards H2O2 in quiescent fluids. Overall, the synthetic biology framework and tracking analysis in this work will provide a framework for investigating controlled motility of E. coli and other 'smart' probiotics for signal-directed treatment.

The Role of Structural Dynamics of Actin in Class-Specific Myosin Motility

PubMed Central

Noguchi, Taro Q. P.; Morimatsu, Masatoshi; Iwane, Atsuko H.; Yanagida, Toshio; Uyeda, Taro Q. P.

2015-01-01

The structural dynamics of actin, including the tilting motion between the small and large domains, are essential for proper interactions with actin-binding proteins. Gly146 is situated at the hinge between the two domains, and we previously showed that a G146V mutation leads to severe motility defects in skeletal myosin but has no effect on motility of myosin V. The present study tested the hypothesis that G146V mutation impaired rotation between the two domains, leading to such functional defects. First, our study showed that depolymerization of G146V filaments was slower than that of wild-type filaments. This result is consistent with the distinction of structural states of G146V filaments from those of the wild type, considering the recent report that stabilization of actin filaments involves rotation of the two domains. Next, we measured intramolecular FRET efficiencies between two fluorophores in the two domains with or without skeletal muscle heavy meromyosin or the heavy meromyosin equivalent of myosin V in the presence of ATP. Single-molecule FRET measurements showed that the conformations of actin subunits of control and G146V actin filaments were different in the presence of skeletal muscle heavy meromyosin. This altered conformation of G146V subunits may lead to motility defects in myosin II. In contrast, distributions of FRET efficiencies of control and G146V subunits were similar in the presence of myosin V, consistent with the lack of motility defects in G146V actin with myosin V. The distribution of FRET efficiencies in the presence of myosin V was different from that in the presence of skeletal muscle heavy meromyosin, implying that the roles of actin conformation in myosin motility depend on the type of myosin. PMID:25945499

Management of pediatric patients with refractory constipation who fail cecostomy.

PubMed

Bonilla, Silvana F; Flores, Alejandro; Jackson, Carl-Christian A; Chwals, Walter J; Orkin, Bruce A

2013-09-01

Antegrade continence enema (ACE) is a recognized therapeutic option in the management of pediatric refractory constipation. Data on the long-term outcome of patients who fail to improve after an ACE-procedure are lacking. To describe the rate of ACE bowel management failure in pediatric refractory constipation, and the management and long term outcome of these patients. Retrospective analysis of a cohort of patients that underwent ACE-procedure and had at least 3-year-follow-up. Detailed analysis of subsequent treatment and outcome of those patients with a poor functional outcome was performed. 76 patients were included. 12 (16%) failed successful bowel management after ACE requiring additional intervention. Mean follow-up was 66.3 (range 35-95 months) after ACE-procedure. Colonic motility studies demonstrated colonic neuropathy in 7 patients (58%); abnormal motility in 4 patients (33%), and abnormal left-sided colonic motility in 1 patient (9%). All 12 patients were ultimately treated surgically. Nine patients (75%) had marked clinical improvement, whereas 3 patients (25%) continued to have poor function issues at long term follow-up. Colonic resection, either segmental or total, led to improvement or resolution of symptoms in the majority of patients who failed cecostomy. However, this is a complex and heterogeneous group and some patients will have continued issues. Copyright © 2013 Elsevier Inc. All rights reserved.

Multiciliated Cells in Animals.

PubMed

Meunier, Alice; Azimzadeh, Juliette

2016-12-01

Many animal cells assemble single cilia involved in motile and/or sensory functions. In contrast, multiciliated cells (MCCs) assemble up to 300 motile cilia that beat in a coordinate fashion to generate a directional fluid flow. In the human airways, the brain, and the oviduct, MCCs allow mucus clearance, cerebrospinal fluid circulation, and egg transportation, respectively. Impairment of MCC function leads to chronic respiratory infections and increased risks of hydrocephalus and female infertility. MCC differentiation during development or repair involves the activation of a regulatory cascade triggered by the inhibition of Notch activity in MCC progenitors. The downstream events include the simultaneous assembly of a large number of basal bodies (BBs)-from which cilia are nucleated-in the cytoplasm of the differentiating MCCs, their migration and docking at the plasma membrane associated to an important remodeling of the actin cytoskeleton, and the assembly and polarization of motile cilia. The direction of ciliary beating is coordinated both within cells and at the tissue level by a combination of planar polarity cues affecting BB position and hydrodynamic forces that are both generated and sensed by the cilia. Herein, we review the mechanisms controlling the specification and differentiation of MCCs and BB assembly and organization at the apical surface, as well as ciliary assembly and coordination in MCCs. Copyright © 2016 Cold Spring Harbor Laboratory Press; all rights reserved.

Major regulatory mechanisms involved in sperm motility

PubMed Central

Pereira, Rute; Sá, Rosália; Barros, Alberto; Sousa, Mário

2017-01-01

The genetic bases and molecular mechanisms involved in the assembly and function of the flagellum components as well as in the regulation of the flagellar movement are not fully understood, especially in humans. There are several causes for sperm immotility, of which some can be avoided and corrected, whereas other are related to genetic defects and deserve full investigation to give a diagnosis to patients. This review was performed after an extensive literature search on the online databases PubMed, ScienceDirect, and Web of Science. Here, we review the involvement of regulatory pathways responsible for sperm motility, indicating possible causes for sperm immotility. These included the calcium pathway, the cAMP-dependent protein kinase pathway, the importance of kinases and phosphatases, the function of reactive oxygen species, and how the regulation of cell volume and osmolarity are also fundamental components. We then discuss main gene defects associated with specific morphological abnormalities. Finally, we slightly discuss some preventive and treatments approaches to avoid development of conditions that are associated with unspecified sperm immotility. We believe that in the near future, with the development of more powerful techniques, the genetic causes of sperm immotility and the regulatory mechanisms of sperm motility will be better understand, thus enabling to perform a full diagnosis and uncover new therapies. PMID:26680031

Effects of chronic dietary exposure to monosodium glutamate on feeding behavior, adiposity, gastrointestinal motility, and cardiovascular function in healthy adult rats.

PubMed

López-Miranda, V; Soto-Montenegro, M L; Uranga-Ocio, J A; Vera, G; Herradón, E; González, C; Blas, C; Martínez-Villaluenga, M; López-Pérez, A E; Desco, M; Abalo, R

2015-11-01

Monosodium glutamate (MSG) is a flavor-enhancer widely used as a food additive. However, its safe dietary concentration and its toxicity, including its possible implication in the recent metabolic syndrome pandemia, is still a controversial issue. Therefore, a deep knowledge of its effects upon regular dietary use is needed. Our aim was to evaluate the effects of chronic exposure to MSG on feeding behavior, abdominal fat, gastrointestinal motility, and cardiovascular function in rats. Two groups of adult male Wistar rats were used: control and treated with MSG (4 g/L in drinking water) for 6 weeks. Different functional parameters were determined and the histological structure was analyzed in tissues of interest. Compared to control animals, chronic MSG increased water intake but did not modify food ingestion or body weight gain. Neither the abdominal fat volume nor the fat fraction, measured by magnetic resonance imaging, was modified by MSG. Monosodium glutamate did not alter general gastrointestinal motility, but significantly increased the colonic response to mechanical stimulation. It slightly reduced endothelium-dependent relaxation in aorta, without significantly modifying any other cardiovascular parameters. No significant histological alterations were detected in salivary glands, intestinal wall, aorta, heart, and kidney. Chronic treatment with MSG in the adult rat increased water intake. This supports its potential to improve acceptance of low-fat regimens and to increase hydration in the elderly and sportspeople, often at risk of dehydration. Changes in colonic contractility and cardiovascular function could have some long-term repercussions warranting further research. © 2015 John Wiley & Sons Ltd.

Copy number variation of functional RBMY1 is associated with sperm motility: an azoospermia factor-linked candidate for asthenozoospermia.

PubMed

Yan, Yuanlong; Yang, Xiling; Liu, Yunqiang; Shen, Ying; Tu, Wenling; Dong, Qiang; Yang, Dong; Ma, Yongyi; Yang, Yuan

2017-07-01

What is the influence of copy number variation (CNV) in functional RNA binding motif protein Y-linked family 1 (RBMY1) on spermatogenic phenotypes? The RBMY1 functional copy dosage is positively correlated with sperm motility, and dosage insufficiency is an independent risk factor for asthenozoospermia. RBMY1, a multi-copy gene expressed exclusively in the adult testis, is one of the most important candidates for male infertility in the azoospermia factor (AZF) region of the Y-chromosome. RBMY1 encodes an RNA-binding protein that serves as a pre-mRNA splicing regulator during spermatogenesis, and male mice deficient in Rbmy are sterile. A total of 3127 adult males were recruited from 2009 to 2016; of this group, the dosage of RBMY1 functional copy were investigated in 486 fertile males. In the remaining 2641 males with known spermatogenesis status, 1070 Y-chromosome haplogroup (Y-hg) O3* or O3e carriers without chromosomal aberration or known AZF structure mutations responsible for spermatogenic impairment, including 506 men with normozoospermia and 564 men with oligozoospermia or/and asthenozoospermia, were screened, and the RBMY1 functional copy dosage and copy conversion were determined to explore their associations with sperm phenotypes. The correlation between RBMY1 dosage and its mRNA level or RBMY1 protein level and the correlation between sperm RBMY1 level and motility were analysed in 15 testis tissue samples and eight semen samples. Ten additional semen samples were used to confirm the subcellular localization of RBMY1 in individual sperm. All the Han volunteers donating whole blood, semen and testis tissue were from southwest China. RBMY1 copy number, copy conversion, mRNA/protein amount and protein location in sperm were detected using the AccuCopy® assay method, paralog ratio test, quantitative PCR, western blotting and immunofluorescence staining methods, respectively. This study identified Y-hg-independent CNV of functional RBMY1 in the enrolled population. A difference in the distribution of RBMY1 copy number was observed between the group with normal sperm motility and the group with asthenozoospermia. A positive correlation between the RBMY1 copy dosage and sperm motility was identified, and the males with fewer than six copies of RBMY1 showed an elevated risk for asthenozoospermia relative to those with six RBMY1 copies, the most common dosage in the population. The RBMY1 copy dosage was positively correlated with its mRNA and protein level in the testis. Sperm with high motility were found to carry more RBMY1 protein than those with relatively low motility. The RBMY1 protein was confirmed to predominantly localize in the neck and mid-piece region of sperm as well as the principal piece of the sperm tail. Our population study completes a chain of evidence suggesting that RBMY1 influences the susceptibility of males to asthenozoospermia by modulating sperm motility. High sequence similarity between the RBMY1 functional copies and a large number of pseudogenes potentially reduces the accuracy of the copy number detection. The mechanism underlying the CNV in RBMY1 is still unclear, and the effect of the structural variations in the RBMY1 copy cluster on the copy dosage of other protein-coding genes located in the region cannot be excluded, which may potentially bias our observations. Asthenozoospermia is a multi-factor complex disease with a limited number of proven susceptibility genes. This study identified a novel genomic candidate independently contributing to the condition, enriching our understanding of the role of AZF-linked genes in male reproduction. Our finding provides insight into the physiological and pathological characteristics of RBMY1 in terms of sperm motility, supplies persuasive evidence of the significance of RBMY1 copy number analysis in the clinical counselling of male infertility resulting from asthenozoospermia. This work was funded by the National Natural Science Foundation of China (Nos. 81370748 and 30971598). The authors have no conflicts of interest. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Transcriptome analysis of functional differentiation between haploid and diploid cells of Emiliania huxleyi, a globally significant photosynthetic calcifying cell.

PubMed

von Dassow, Peter; Ogata, Hiroyuki; Probert, Ian; Wincker, Patrick; Da Silva, Corinne; Audic, Stéphane; Claverie, Jean-Michel; de Vargas, Colomban

2009-01-01

Eukaryotes are classified as either haplontic, diplontic, or haplo-diplontic, depending on which ploidy levels undergo mitotic cell division in the life cycle. Emiliania huxleyi is one of the most abundant phytoplankton species in the ocean, playing an important role in global carbon fluxes, and represents haptophytes, an enigmatic group of unicellular organisms that diverged early in eukaryotic evolution. This species is haplo-diplontic. Little is known about the haploid cells, but they have been hypothesized to allow persistence of the species between the yearly blooms of diploid cells. We sequenced over 38,000 expressed sequence tags from haploid and diploid E. huxleyi normalized cDNA libraries to identify genes involved in important processes specific to each life phase (2N calcification or 1N motility), and to better understand the haploid phase of this prominent haplo-diplontic organism. The haploid and diploid transcriptomes showed a dramatic differentiation, with approximately 20% greater transcriptome richness in diploid cells than in haploid cells and only

Transcriptome analysis of functional differentiation between haploid and diploid cells of Emiliania huxleyi, a globally significant photosynthetic calcifying cell

PubMed Central

2009-01-01

Background Eukaryotes are classified as either haplontic, diplontic, or haplo-diplontic, depending on which ploidy levels undergo mitotic cell division in the life cycle. Emiliania huxleyi is one of the most abundant phytoplankton species in the ocean, playing an important role in global carbon fluxes, and represents haptophytes, an enigmatic group of unicellular organisms that diverged early in eukaryotic evolution. This species is haplo-diplontic. Little is known about the haploid cells, but they have been hypothesized to allow persistence of the species between the yearly blooms of diploid cells. We sequenced over 38,000 expressed sequence tags from haploid and diploid E. huxleyi normalized cDNA libraries to identify genes involved in important processes specific to each life phase (2N calcification or 1N motility), and to better understand the haploid phase of this prominent haplo-diplontic organism. Results The haploid and diploid transcriptomes showed a dramatic differentiation, with approximately 20% greater transcriptome richness in diploid cells than in haploid cells and only ≤ 50% of transcripts estimated to be common between the two phases. The major functional category of transcripts differentiating haploids included signal transduction and motility genes. Diploid-specific transcripts included Ca2+, H+, and HCO3- pumps. Potential factors differentiating the transcriptomes included haploid-specific Myb transcription factor homologs and an unusual diploid-specific histone H4 homolog. Conclusions This study permitted the identification of genes likely involved in diploid-specific biomineralization, haploid-specific motility, and transcriptional control. Greater transcriptome richness in diploid cells suggests they may be more versatile for exploiting a diversity of rich environments whereas haploid cells are intrinsically more streamlined. PMID:19832986

Sodium–hydrogen exchanger NHA1 and NHA2 control sperm motility and male fertility

PubMed Central

Chen, Su-Ren; Chen, M; Deng, S-L; Hao, X-X; Wang, X-X; Liu, Y-X

2016-01-01

Our previous work identified NHA1, a testis-specific sodium–hydrogen exchanger, is specifically localized on the principal piece of mouse sperm flagellum. Our subsequent study suggested that the number of newborns and fertility rate of NHA1-vaccinated female mice are significantly stepped down. In order to define the physiological function of NHA1 in spermatozoa, we generated Nha1Fx/Fx, Zp3-Cre (hereafter called Nha1 cKO) mice and found that Nha1 cKO males were viable and subfertile with reduced sperm motility. Notably, cyclic AMP (cAMP) synthesis by soluble adenylyl cyclase (sAC) was attenuated in Nha1 cKO spermatozoa and cAMP analogs restored sperm motility. Similar to Nha1 cKO males, Nha2Fx/Fx, Zp3-Cre (hereafter called Nha2 cKO) male mice were subfertile, indicating these two Nha genes may be functionally redundant. Furthermore, we demonstrated that male mice lacking Nha1 and Nha2 genes (hereafter called Nha1/2 dKO mice) were completely infertile, with severely diminished sperm motility owing to attenuated sAC-cAMP signaling. Importantly, principal piece distribution of NHA1 in spermatozoa are phylogenetically conserved in spermatogenesis. Collectively, our data revealed that NHA1 and NHA2 function as a key sodium–hydrogen exchanger responsible for sperm motility after leaving the cauda epididymidis. PMID:27010853

Eukaryotic Chemotaxis: A Network of Signaling Pathways Controls Motility, Directional Sensing, and Polarity

PubMed Central

Swaney, Kristen F.; Huang, Chuan-Hsiang; Devreotes, Peter N.

2015-01-01

Chemotaxis, the directed migration of cells in chemical gradients, is a vital process in normal physiology and in the pathogenesis of many diseases. Chemotactic cells display motility, directional sensing, and polarity. Motility refers to the random extension of pseudopodia, which may be driven by spontaneous actin waves that propagate through the cytoskeleton. Directional sensing is mediated by a system that detects temporal and spatial stimuli and biases motility toward the gradient. Polarity gives cells morphologically and functionally distinct leading and lagging edges by relocating proteins or their activities selectively to the poles. By exploiting the genetic advantages of Dictyostelium, investigators are working out the complex network of interactions between the proteins that have been implicated in the chemotactic processes of motility, directional sensing, and polarity. PMID:20192768

Influence of the Enteric Nervous System on Gut Motility Patterns in Zebrafish

NASA Astrophysics Data System (ADS)

Baker, Ryan; Ganz, Julia; Melancon, Ellie; Eisen, Judith; Parthasarathy, Raghuveer

The enteric nervous system (ENS), composed of diverse neuronal subtypes and glia, regulates essential gut functions including motility, secretion, and homeostasis. In humans and animals, decreased numbers of enteric neurons lead to a variety of types of gut dysfunction. However, surprisingly little is known about how the number, position, or subtype of enteric neurons affect the regulation of gut peristalsis, due to the lack of good model systems and the lack of tools for the quantitative characterization of gut motion. We have therefore developed a method of quantitative spatiotemporal mapping using differential interference contrast microscopy and particle image velocimetry, and have applied this to investigate intestinal dynamics in normal and mutant larval zebrafish. From movies of gut motility, we obtain a velocity vector field representative of gut motion, from which we can quantify parameters relating to gut peristalsis such as frequency, wave speed, deformation amplitudes, wave duration, and non-linearity of waves. We show that mutants with reduced neuron number have contractions that are more regular in time and reduced in amplitude compared to wild-type (normal) fish. We also show that feeding fish before their yolk is consumed leads to stronger motility patterns. We acknowledge support from NIH awards P50 GM098911 and P01 HD022486.

Transposon Insertions of magellan-4 That Impair Social Gliding Motility in Myxococcus xanthus

PubMed Central

Youderian, Philip; Hartzell, Patricia L.

2006-01-01

Myxococcus xanthus has two different mechanisms of motility, adventurous (A) motility, which permits individual cells to glide over solid surfaces, and social (S) motility, which permits groups of cells to glide. To identify the genes involved in S-gliding motility, we mutagenized a ΔaglU (A−) strain with the defective transposon, magellan-4, and screened for S− mutants that form nonmotile colonies. Sequence analysis of the sites of the magellan-4 insertions in these mutants and the alignment of these sites with the M. xanthus genome sequence show that two-thirds of these insertions lie within 27 of the 37 nonessential genes known to be required for social motility, including those necessary for the biogenesis of type IV pili, exopolysaccharide, and lipopolysaccharide. The remaining insertions also identify 31 new, nonessential genes predicted to encode both structural and regulatory determinants of S motility. These include three tetratricopeptide repeat proteins, several regulators of transcription that may control the expression of genes involved in pilus extension and retraction, and additional enzymes involved in polysaccharide metabolism. Three insertions that abolish S motility lie within genes predicted to encode glycolytic enzymes, suggesting that the signal for pilus retraction may be a simple product of exopolysaccharide catabolism. PMID:16299386

Calcium channels in chicken sperm regulate motility and the acrosome reaction.

PubMed

Nguyen, Thi Mong Diep; Duittoz, Anne; Praud, Christophe; Combarnous, Yves; Blesbois, Elisabeth

2016-05-01

Intracellular cytoplasmic calcium ([Ca(2+) ]i ) has an important regulatory role in gamete functions. However, the biochemical components involved in Ca(2+) transport are still unknown in birds, an animal class that has lost functional sperm-specific CatSper channels. Here, we provide evidence for the presence and expression of various Ca(2+) channels in chicken sperm, including high voltage-activated channels (L and R types), the store-operated Ca(2+) channel (SOC) component Orai1, the transient receptor potential channel (TRPC1) and inositol-1,4,5-trisphosphate receptors (IP3 R1). L- and R-type channels were mainly localized in the acrosome and the midpiece, and T-type channels were not detected in chicken sperm. Orai1 was found in all compartments, but with a weak, diffuse signal in the flagellum. TRCP1 was mainly localized in the acrosome and the midpiece, but a weak diffuse signal was also observed in the nucleus and the flagellum. IP3 R1 was mainly detected in the nucleus. The L-type channel inhibitor nifedipine, the R-type channel inhibitor SNX-482 and the SOC inhibitors MRS-1845, 2-APB and YM-58483 decreased [Ca(2+) ]i sperm motility and acrosome reaction capability, with the SOC inhibitors inhibiting these functions most efficiently. Furthermore, we showed that Ca(2+) -mediated induction of AMP-activated protein kinase (AMPK) phosphorylation was blocked by SOC inhibition. Our identification of important regulators of Ca(2+) signaling in avian sperm suggests that SOCs play a predominant role in gamete function, whereas T-type channels may not be involved. In addition, Ca(2+) entry via SOCs appears to be the most likely pathway for AMPK activation and energy-requiring sperm functions such as motility and the acrosome reaction. © 2016 Federation of European Biochemical Societies.

Androgen receptor and chemokine receptors 4 and 7 form a signaling axis to regulate CXCL12-dependent cellular motility.

PubMed

Hsiao, Jordy J; Ng, Brandon H; Smits, Melinda M; Wang, Jiahui; Jasavala, Rohini J; Martinez, Harryl D; Lee, Jinhee; Alston, Jhullian J; Misonou, Hiroaki; Trimmer, James S; Wright, Michael E

2015-03-31

Identifying cellular signaling pathways that become corrupted in the presence of androgens that increase the metastatic potential of organ-confined tumor cells is critical to devising strategies capable of attenuating the metastatic progression of hormone-naïve, organ-confined tumors. In localized prostate cancers, gene fusions that place ETS-family transcription factors under the control of androgens drive gene expression programs that increase the invasiveness of organ-confined tumor cells. C-X-C chemokine receptor type 4 (CXCR4) is a downstream target of ERG, whose upregulation in prostate-tumor cells contributes to their migration from the prostate gland. Recent evidence suggests that CXCR4-mediated proliferation and metastasis of tumor cells is regulated by CXCR7 through its scavenging of chemokine CXCL12. However, the role of androgens in regulating CXCR4-mediated motility with respect to CXCR7 function in prostate-cancer cells remains unclear. Immunocytochemistry, western blot, and affinity-purification analyses were used to study how androgens influenced the expression, subcellular localization, and function of CXCR7, CXCR4, and androgen receptor (AR) in LNCaP prostate-tumor cells. Moreover, luciferase assays and quantitative polymerase chain reaction (qPCR) were used to study how chemokines CXCL11 and CXCL12 regulate androgen-regulated genes (ARGs) in LNCaP prostate-tumor cells. Lastly, cell motility assays were carried out to determine how androgens influenced CXCR4-dependent motility through CXCL12. Here we show that, in the LNCaP prostate-tumor cell line, androgens coordinate the expression of CXCR4 and CXCR7, thereby promoting CXCL12/CXCR4-mediated cell motility. RNA interference experiments revealed functional interactions between AR and CXCR7 in these cells. Co-localization and affinity-purification experiments support a physical interaction between AR and CXCR7 in LNCaP cells. Unexpectedly, CXCR7 resided in the nuclear compartment and modulated AR-mediated transcription. Moreover, androgen-mediated cell motility correlated positively with the co-localization of CXCR4 and CXCR7 receptors, suggesting that cell migration may be linked to functional CXCR4/CXCR7 heterodimers. Lastly, CXCL12-mediated cell motility was CXCR7-dependent, with CXCR7 expression required for optimal expression of CXCR4 protein. Overall, our results suggest that inhibition of CXCR7 function might decrease the metastatic potential of organ-confined prostate cancers.

Undersized description on motile gyrotactic micro-organisms individualities in MHD stratified water-based Newtonian nanofluid

NASA Astrophysics Data System (ADS)

Rehman, Khalil Ur; Malik, Aneeqa Ashfaq; Tahir, M.; Malik, M. Y.

2018-03-01

The current pagination summarized the influence of bio-convection Schmidt number, bio-convection Peclet number and micro-organisms concentration difference parameter on the density of motile gyrotactic micro-organisms when they have interaction with the thermally stratified magneto-nanofluid flow past a vertical stretching surface. It is observed that the density of motile microorganisms is the decreasing function of the bio-convection Schmidt and Peclet numbers. It is trusted that the outcomes of present analysis will serve as a helping source for the upcoming developments regarding individualities of motile gyrotactic micro-organisms subject to boundary layer flows induced by stretching surfaces.

Neuropeptide S reduces duodenal bicarbonate secretion and ethanol-induced increases in duodenal motility in rats

PubMed Central

Wan Saudi, Wan Salman

2017-01-01

Alcohol disrupts the intestinal mucosal barrier by inducing metabolic and functional changes in epithelial cells. Recently, we showed that neuropeptide S (NPS) decreases duodenal motility and increases mucosal paracellular permeability, suggesting a role of NPS in the pathogenesis of disorders and dysfunctions in the small intestine. The aim of the present study was to investigate the effects of NPS on ethanol- and HCl-induced changes of duodenal mucosal barrier function and motility. Rats were anaesthetized with thiobarbiturate, and a 30-mm segment of the proximal duodenum with an intact blood supply was perfused in situ. The effects on duodenal bicarbonate secretion, the blood-to-lumen clearance of 51Cr-EDTA, motility and transepithelial net fluid flux were investigated. Intravenous (i.v.) administration of NPS significantly reduced duodenal mucosal bicarbonate secretion and stimulated mucosal transepithelial fluid absorption, mechanisms dependent on nitrergic signaling. NPS dose-dependently reduced ethanol-induced increases in duodenal motility. NPS (83 pmol·kg-1·min-1, i.v.) reduced the bicarbonate and fluid secretory response to luminal ethanol, whereas a 10-fold higher dose stimulated fluid secretion but did not influence bicarbonate secretion. In NPS-treated animals, duodenal perfusion of acid (pH 3) induced greater bicarbonate secretory rates than in controls. Pre-treating animals with Nω-nitro-L-arginine methyl ester (L-NAME) inhibited the effect of NPS on bicarbonate secretion. In response to luminal acid, NPS-treated animals had significantly higher paracellular permeability compared to controls, an effect that was abolished by L-NAME. Our findings demonstrate that NPS reduces basal and ethanol-induced increases in duodenal motility. In addition, NPS increases luminal alkalinization and mucosal permeability in response to luminal acid via mechanisms that are dependent on nitric oxide signaling. The data support a role for NPS in neurohumoral regulation of duodenal mucosal barrier function and motility. PMID:28384243

Seminal Plasma pH, Inorganic Phosphate, Total and Ionized Calcium Concentrations In The Assessment of Human Spermatozoa Function.

PubMed

Banjoko, S Olatunbosun; Adeseolu, Fasiu O

2013-11-01

Fertilization in humans is dependent on viability of the male spermatozoa among other factors and there have been conflicting reports on the role of pH, calcium and phosphate concentrations in sperm function. This study therefore aimed to investigate seminal plasma pH, inorganic phosphate, total and ionized calcium concentrations relative to spermatozoa function. Seminal plasma concentrations of pH, total calcium, ionized calcium (Ca(++)); inorganic phosphate, motility and spermatozoa count were determined in 80 males by standard methods. Forty-nine of the subjects had normal spermatozoa motility (> 60%) and 31 had hypomotility (< 60%). The hypomotility group exhibited lower calcium ion (Ca(2)+) concentrations; 0.19+0.01mmol/L compared with normal motility group; 0.24+0.01mmol/L (p<0.001) the latter also had significantly higher inorganic phosphate; 7.83+1.27 while the former had 5.64+1.62mmol/L (p= 0.004). The mean spermatozoa counts for hypomotility and normal motility group were 42.0 ± 13 x 106 , 72.35 + 20 x 106 respectively (p< 0.001). No significant differences were observed in pH, volume of ejaculate and total calcium concentration between the hypomotility and normal motility groups The mean concentrations of pH were 7.51 ± 0.02 and 7.54 ± 0.03 respectively (p= 0.21) and total calcium; 3.10 ± 0.12 and 3.36 ± 0.14mmol/L respectively (p= 0.16 ). There was a significant difference in percentage of abnormal forms in both groups with hypomotile group having 36% compared to mormal motility group with 5% (p< 0.05). Correlations were observed between seminal concentrations of calcium ions, inorganic phosphate, spermatozoa count and motility but not with total calcium concentrations and pH and therefore should be considered in understanding male infertility and preparation of media for sperm preservation for in vitro fertilization.

Novel genes associated with enhanced motility of Escherichia coli ST131

PubMed Central

Kakkanat, Asha; Phan, Minh-Duy; Lo, Alvin W.; Beatson, Scott A.

2017-01-01

Uropathogenic Escherichia coli (UPEC) is the cause of ~75% of all urinary tract infections (UTIs) and is increasingly associated with multidrug resistance. This includes UPEC strains from the recently emerged and globally disseminated sequence type 131 (ST131), which is now the dominant fluoroquinolone-resistant UPEC clone worldwide. Most ST131 strains are motile and produce H4-type flagella. Here, we applied a combination of saturated Tn5 mutagenesis and transposon directed insertion site sequencing (TraDIS) as a high throughput genetic screen and identified 30 genes associated with enhanced motility of the reference ST131 strain EC958. This included 12 genes that repress motility of E. coli K-12, four of which (lrhA, ihfA, ydiV, lrp) were confirmed in EC958. Other genes represented novel factors that impact motility, and we focused our investigation on characterisation of the mprA, hemK and yjeA genes. Mutation of each of these genes in EC958 led to increased transcription of flagellar genes (flhD and fliC), increased expression of the FliC flagellin, enhanced flagella synthesis and a hyper-motile phenotype. Complementation restored all of these properties to wild-type level. We also identified Tn5 insertions in several intergenic regions (IGRs) on the EC958 chromosome that were associated with enhanced motility; this included flhDC and EC958_1546. In both of these cases, the Tn5 insertions were associated with increased transcription of the downstream gene(s), which resulted in enhanced motility. The EC958_1546 gene encodes a phage protein with similarity to esterase/deacetylase enzymes involved in the hydrolysis of sialic acid derivatives found in human mucus. We showed that over-expression of EC958_1546 led to enhanced motility of EC958 as well as the UPEC strains CFT073 and UTI89, demonstrating its activity affects the motility of different UPEC strains. Overall, this study has identified and characterised a number of novel factors associated with enhanced UPEC motility. PMID:28489862

Loss of Peristaltic Reserve, Determined by Multiple Rapid Swallows, Is the Most Frequent Esophageal Motility Abnormality in Patients With Systemic Sclerosis.

PubMed

Carlson, Dustin A; Crowell, Michael D; Kimmel, Jessica N; Patel, Amit; Gyawali, C Prakash; Hinchcliff, Monique; Griffing, W Leroy; Pandolfino, John E; Vela, Marcelo F

2016-10-01

We assessed peristaltic reserve using multiple rapid swallows (MRS) during esophageal high-resolution manometry (HRM) of 111 patients with systemic sclerosis (89 women; ages, 42-64 y). We performed a retrospective analysis of HRM studies that included MRS in patients with systemic sclerosis, performed at 2 tertiary referral centers, and compared data with those from 18 healthy volunteers (controls). HRM findings were analyzed according to the Chicago Classification to provide an esophageal motility diagnosis. Response to MRS was evaluated for the presence of contraction and for augmentation, defined as the distal contractile integral after MRS greater than the median distal contractile integral of 10 supine swallows. Esophageal motility diagnoses included 41% with absent contractility, 31% with normal motility, 23% with ineffective esophageal motility, and 5% that met the criteria for other esophageal motility disorders. Contraction (37%) and peristaltic augmentation (18%) after MRS were observed less frequently in patients with systemic sclerosis than in controls (83% and 100%, respectively). Impaired peristaltic reserve, as assessed with MRS during HRM, is therefore the most common esophageal motility finding among patients with systemic sclerosis. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong, Yan; Hirane, Miku; Araki, Mutsumi

2014-04-04

Highlights: • LPA{sub 5} inhibits the cell growth and motile activities of 3T3 cells. • LPA{sub 5} suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA{sub 5} on the cell motile activities inhibited by LPA{sub 1} in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA{sub 5} in 3T3 cells. • LPA signaling via LPA{sub 5} acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA{sub 1}–LPA{sub 6}) mediates a variety of biological functions, including cellmore » migration. Recently, we have reported that LPA{sub 1} inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA{sub 5} in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA{sub 1} and LPA{sub 5} on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA{sub 5} may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA{sub 1}.« less

Bovine sperm separation by Swim-up and density gradients (Percoll and BoviPure): Effect on sperm quality, function and gene expression.

PubMed

Arias, María Elena; Andara, Katherine; Briones, Evelyn; Felmer, Ricardo

2017-06-01

This study assesses the effect of bovine sperm (obtained from three bulls) separation using density gradients (Percoll and BoviPure) and Swim-up on sperm function and gene expression. Sperm evaluations included the plasma membrane integrity (SYBR14/PI), acrosomal integrity (PNA-FITC/PI), oxidative stress (ROS; CH2FDDA), DNA fragmentation (TUNEL assay) and mitochondrial membrane potential (ΔYm; TMRM) using flow cytometry. Sperm motility was evaluated by computer-assisted sperm analysis (CASA) and gene expression using RT-qPCR. The results showed that separation by Percoll achieves a higher proportion of sperm with intact plasma and acrosomal membranes (89.8 and 87.5%, respectively) than the unseparated control (70.3 and 62.4%, respectively), as well as by Swim-up (74.9 and 63.3%, respectively) and BoviPure (83.3 and 80.4%, respectively). No differences were observed in the proportion of spermatozoa with high ΔΨm between Percoll and BoviPure (84.3% and 83.5%, respectively), which were higher than Swim-up and the unseparated control (72.8% and 43.8%, respectively). The ROS levels were higher in the spermatozoa separated by Percoll and no differences were observed in the sperm DNA integrity between all groups. The motility analysis showed that the separation methods improve (p<0.05) total and progressive motility compared to the control, with Percoll proving the most efficient in this regard. Finally, the gene expression analysis of leptin (LEP), aromatase cytochrome P450 (CYP19) and protamine I (PRM1), after validation of 6 reference genes, showed no differences between groups. In conclusion, bovine sperm separation using density gradient improves the parameters of motility and sperm function without affecting the gene expression. Copyright © 2017 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

MotPS is the stator-force generator for motility of alkaliphilic Bacillus, and its homologue is a second functional Mot in Bacillus subtilis.

PubMed

Ito, Masahiro; Hicks, David B; Henkin, Tina M; Guffanti, Arthur A; Powers, Benjamin D; Zvi, Lior; Uematsu, Katsuyuki; Krulwich, Terry A

2004-08-01

The stator-force generator that drives Na+-dependent motility in alkaliphilic Bacillus pseudofirmus OF4 is identified here as MotPS, MotAB-like proteins with genes that are downstream of the ccpA gene, which encodes a major regulator of carbon metabolism. B. pseudofirmus OF4 was only motile at pH values above 8. Disruption of motPS resulted in a non-motile phenotype, and motility was restored by transformation with a multicopy plasmid containing the motPS genes. Purified and reconstituted MotPS from B. pseudofirmus OF4 catalysed amiloride analogue-sensitive Na+ translocation. In contrast to B. pseudofirmus, Bacillus subtilis contains both MotAB and MotPS systems. The role of the motPS genes from B. subtilis in several motility-based behaviours was tested in isogenic strains with intact motAB and motPS loci, only one of the two mot systems or neither mot system. B. subtilis MotPS (BsMotPS) supported Na+-stimulated motility, chemotaxis on soft agar surfaces and biofilm formation, especially after selection of an up-motile variant. BsMotPS also supported motility in agar soft plugs immersed in liquid; motility was completely inhibited by an amiloride analogue. BsMotPS did not support surfactin-dependent swarming on higher concentration agar surfaces. These results indicate that BsMotPS contributes to biofilm formation and motility on soft agar, but not to swarming, in laboratory strains of B. subtilis in which MotAB is the dominant stator-force generator. BsMotPS could potentially be dominant for motility in B. subtilis variants that arise in particular niches.

Effect of separate and combined exposure of selenium and diazinon on rat sperm motility by computer assisted semen analysis.

PubMed

Toman, Robert; Hluchy, Svatoslav; Cabaj, Michal; Massanyi, Peter; Roychoudhury, Shubhadeep; Tunegova, Martina

2016-12-01

Effects of selenium (Se) and diazinon (DZN) on sperm motility parameters in rats were investigated. Male rats received a separate dose of Se (2mgkg -1 b.w., intraperitoneally, 5mgL -1 , per os in drinking water), diazinon (20mgkg -1 b.w., intraperitoneally, 40mgL -1 , per os in drinking water), and in combination (Se+DZN) with the same dosage as in the separate administration. 36h an intraperitoneal (i.p.) and after 90days of per oral (p.o.) exposure, thirteen parameters of sperm motility were evaluated using a Computer Assisted Sperm Analyzer (CASA). Almost all the evaluated sperm motility parameters significantly decreased in Se p.o. exposed groups. In the Se i.p. group decrease was noted only in beat cross frequency (BCF) and progressive motility. Significant decline in the sperm motility, progressive motility, BCF and increase in amplitude of lateral head displacement (ALH) were recorded after DZN i.p. administration. In DZN p.o. group, significant increase in ALH, velocity average path (VAP) and curvilinear velocity (VCL) but decrease in progressive motility and BCF was detected. Se+DZN i.p. administration caused a significant decrease in motility, progressive motility and BCF. Per oral administration of Se+DZN decreased all motility parameters except LIN, WOB and ALH. Sperm abnormalities increased in all experimental conditions. Se and DZN negatively affected sperm structure and function in separate doses or in combination. No protective effect of Se was observed. Copyright © 2016 Elsevier GmbH. All rights reserved.

Plasmid-Encoded MCP Is Involved in Virulence, Motility, and Biofilm Formation of Cronobacter sakazakii ATCC 29544

PubMed Central

Choi, Younho; Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Kang, Dong-Hyun

2014-01-01

The aim of this study was to elucidate the function of the plasmid-borne mcp (methyl-accepting chemotaxis protein) gene, which plays pleiotropic roles in Cronobacter sakazakii ATCC 29544. By searching for virulence factors using a random transposon insertion mutant library, we identified and sequenced a new plasmid, pCSA2, in C. sakazakii ATCC 29544. An in silico analysis of pCSA2 revealed that it included six putative open reading frames, and one of them was mcp. The mcp mutant was defective for invasion into and adhesion to epithelial cells, and the virulence of the mcp mutant was attenuated in rat pups. In addition, we demonstrated that putative MCP regulates the motility of C. sakazakii, and the expression of the flagellar genes was enhanced in the absence of a functional mcp gene. Furthermore, a lack of the mcp gene also impaired the ability of C. sakazakii to form a biofilm. Our results demonstrate a regulatory role for MCP in diverse biological processes, including the virulence of C. sakazakii ATCC 29544. To the best of our knowledge, this study is the first to elucidate a potential function of a plasmid-encoded MCP homolog in the C. sakazakii sequence type 8 (ST8) lineage. PMID:25332122

Plasmid-encoded MCP is involved in virulence, motility, and biofilm formation of Cronobacter sakazakii ATCC 29544.

PubMed

Choi, Younho; Kim, Seongok; Hwang, Hyelyeon; Kim, Kwang-Pyo; Kang, Dong-Hyun; Ryu, Sangryeol

2015-01-01

The aim of this study was to elucidate the function of the plasmid-borne mcp (methyl-accepting chemotaxis protein) gene, which plays pleiotropic roles in Cronobacter sakazakii ATCC 29544. By searching for virulence factors using a random transposon insertion mutant library, we identified and sequenced a new plasmid, pCSA2, in C. sakazakii ATCC 29544. An in silico analysis of pCSA2 revealed that it included six putative open reading frames, and one of them was mcp. The mcp mutant was defective for invasion into and adhesion to epithelial cells, and the virulence of the mcp mutant was attenuated in rat pups. In addition, we demonstrated that putative MCP regulates the motility of C. sakazakii, and the expression of the flagellar genes was enhanced in the absence of a functional mcp gene. Furthermore, a lack of the mcp gene also impaired the ability of C. sakazakii to form a biofilm. Our results demonstrate a regulatory role for MCP in diverse biological processes, including the virulence of C. sakazakii ATCC 29544. To the best of our knowledge, this study is the first to elucidate a potential function of a plasmid-encoded MCP homolog in the C. sakazakii sequence type 8 (ST8) lineage. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

PIKfyve mediates the motility of late endosomes and lysosomes in neuronal dendrites.

PubMed

Tsuruta, Fuminori; Dolmetsch, Ricardo E

2015-09-25

The endosome/lysosome system in the nervous system is critically important for a variety of neuronal functions such as neurite outgrowth, retrograde transport, and synaptic plasticity. In neurons, the endosome/lysosome system is crucial for the activity-dependent internalization of membrane proteins and contributes to the regulation of lipid level on the plasma membrane. Although homeostasis of membrane dynamics plays important roles in the properties of central nervous systems, it has not been elucidated how endosome/lysosome system is regulated. Here, we report that phosphatidylinositol 3-phosphate 5-kinase (PIKfyve) mediates the motility of late endosomes and lysosomes in neuronal dendrites. Endosomes and lysosomes are highly motile in resting neurons, however knockdown of PIKfyve led to a significant reduction in late endosomes and lysosomes motility. We also found that vesicle acidification is crucial for their motility and PIKfyve is associated with this process indirectly. These data suggest that PIKfyve mediates vesicle motility through the regulation of vesicle integrity in neurons. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Motility modes of the parasite Trypanosoma brucei

NASA Astrophysics Data System (ADS)

Temel, Fatma Zeynep; Qu, Zijie; McAllaster, Michael; de Graffenried, Christopher; Breuer, Kenneth

2015-11-01

The parasitic single-celled protozoan Trypanosoma brucei causes African Sleeping Sickness, which is a fatal disease in humans and animals that threatens more than 60 million people in 36 African countries. Cell motility plays a critical role in the developmental phases and dissemination of the parasite. Unlike many other motile cells such as bacteria Escherichia coli or Caulobacter crescentus, the flagellum of T. brucei is attached along the length of its awl-like body, producing a unique mode of motility that is not fully understood or characterized. Here, we report on the motility of T. brucei, which swims using its single flagellum employing both rotating and undulating propulsion modes. We tracked cells in real-time in three dimensions using fluorescent microscopy. Data obtained from experiments using both short-term tracking within the field of view and long-term tracking using a tracking microscope were analyzed. Motility modes and swimming speed were analyzed as functions of cell size, rotation rate and undulation pattern. Research supported by NSF.

An evolutionary link between capsular biogenesis and surface motility in bacteria.

PubMed

Agrebi, Rym; Wartel, Morgane; Brochier-Armanet, Céline; Mignot, Tâm

2015-05-01

Studying the evolution of macromolecular assemblies is important to improve our understanding of how complex cellular structures evolved, and to identify the functional building blocks that are involved. Recent studies suggest that the macromolecular complexes that are involved in two distinct processes in Myxococcus xanthus - surface motility and sporulation - are derived from an ancestral polysaccharide capsule assembly system. In this Opinion article, we argue that the available data suggest that the motility machinery evolved from this capsule assembly system following a gene duplication event, a change in carbohydrate polymer specificity and the acquisition of additional proteins by the motility complex, all of which are key features that distinguish the motility and sporulation systems. Furthermore, the presence of intermediates of these systems in bacterial genomes suggests a testable evolutionary model for their emergence and spread.

Estimate of oxygen consumption and intracellular zinc concentration of human spermatozoa in relation to motility.

PubMed

Henkel, Ralf R; Defosse, Kerstin; Koyro, Hans-Wilhelm; Weissmann, Norbert; Schill, Wolf-Bernhard

2003-03-01

To investigate the human sperm oxygen/energy consumption and zinc content in relation to motility. In washed spermatozoa from 67 ejaculates, the oxygen consumption was determined. Following calculation of the total oxygen consumed by the Ideal Gas Law, the energy consumption of spermatozoa was calculated. In addition, the zinc content of the sperm was determined using an atomic absorption spectrometer. The resulting data were correlated to the vitality and motility. The oxygen consumption averaged 0.24 micromol/10(6) sperm x 24h, 0.28 micromol/10(6) live sperm x 24h and 0.85 micromol/10(6) live motile sperm x 24h. Further calculations revealed that sperm motility was the most energy consuming process (164.31 mJ/10(6) motile spermatozoa x 24h), while the oxygen consumption of the total spermatozoa was 46.06 mJ/10(6) spermatozoa x 24h. The correlation of the oxygen/energy consumption and zinc content with motility showed significant negative correlations (r= -0.759; P<0.0001 and r=-0.441; P<0.0001, respectively). However, when correlating sperm energy consumption with the zinc content, a significant positive relation (r=0.323; P=0.01) was observed. Poorly motile sperm are actually wasting the available energy. Moreover, our data clearly support the "Geometric Clutch Model" of the axoneme function and demonstrate the importance of the outer dense fibers for the generation of sperm motility, especially progressive motility.

Oligomerization-Dependent Regulation of Motility and Morphogenesis by the Collagen Xviii Nc1/Endostatin Domain

PubMed Central

Kuo, Calvin J.; LaMontagne, Kenneth R.; Garcia-Cardeña, Guillermo; Ackley, Brian D.; Kalman, Daniel; Park, Susan; Christofferson, Rolf; Kamihara, Junne; Ding, Yuan-Hua; Lo, Kin-Ming; Gillies, Stephen; Folkman, Judah; Mulligan, Richard C.; Javaherian, Kashi

2001-01-01

Collagen XVIII (c18) is a triple helical endothelial/epithelial basement membrane protein whose noncollagenous (NC)1 region trimerizes a COOH-terminal endostatin (ES) domain conserved in vertebrates, Caenorhabditis elegans and Drosophila. Here, the c18 NC1 domain functioned as a motility-inducing factor regulating the extracellular matrix (ECM)-dependent morphogenesis of endothelial and other cell types. This motogenic activity required ES domain oligomerization, was dependent on rac, cdc42, and mitogen-activated protein kinase, and exhibited functional distinction from the archetypal motogenic scatter factors hepatocyte growth factor and macrophage stimulatory protein. The motility-inducing and mitogen-activated protein kinase–stimulating activities of c18 NC1 were blocked by its physiologic cleavage product ES monomer, consistent with a proteolysis-dependent negative feedback mechanism. These data indicate that the collagen XVIII NC1 region encodes a motogen strictly requiring ES domain oligomerization and suggest a previously unsuspected mechanism for ECM regulation of motility and morphogenesis. PMID:11257123

Characterisation of chicken TES and its role in cell spreading and motility.

PubMed

Griffith, Elen; Coutts, Amanda S; Black, Donald M

2004-03-01

Previously we identified TES as a candidate tumour suppressor gene that is located at human chromosome 7q31.1. More recently, we and others have shown TES to encode a novel LIM domain protein that localises to focal adhesions. Here, we present the cloning and functional analysis of the chicken orthologue of TES, cTES. The TES proteins are highly conserved between chicken and human, showing 89% identity at the amino acid level. We show that the cTES protein localised at focal adhesions, actin stress fibres, and sites of cell-cell contact, and GST-cTES can pull-down zyxin and actin. To investigate a functional role for cTES, we looked at the effect of its overexpression on cell spreading and cell motility. Cells overexpressing cTES showed increased cell spreading on fibronectin, and decreased cell motility, compared to RCAS vector transfected control cells. The data from our studies with cTES support our previous findings with human TES and further implicate TES as a member of a complex of proteins that function together to regulate cell adhesion and additionally demonstrate a role for TES in cell motility. Copyright 2004 Wiley-Liss, Inc.

Epidermal keratinocyte polarity and motility require Ca2+ influx through TRPV1

PubMed Central

Graham, David M.; Huang, Ling; Robinson, Kenneth R.; Messerli, Mark A.

2013-01-01

Summary Ca2+ has long been known to play an important role in cellular polarity and guidance. We studied the role of Ca2+ signaling during random and directed cell migration to better understand whether Ca2+ directs cell motility from the leading edge and which ion channels are involved in this function by using primary zebrafish keratinocytes. Rapid line-scan and time-lapse imaging of intracellular Ca2+ (Ca2+i) during migration and automated image alignment enabled us to characterize and map the spatiotemporal changes in Ca2+i. We show that asymmetric distributions of lamellipodial Ca2+ sparks are encoded in frequency, not amplitude, and that they correlate with cellular rotation during migration. Directed migration during galvanotaxis increases the frequency of Ca2+ sparks over the entire lamellipod; however, these events do not give rise to asymmetric Ca2+i signals that correlate with turning. We demonstrate that Ca2+-permeable channels within these cells are mechanically activated and include several transient receptor potential family members, including TRPV1. Last, we demonstrate that cell motility and Ca2+i activity are affected by pharmacological agents that target TRPV1, indicating a novel role for this channel during cell migration. PMID:23943873

Mitochondrial motility and vascular smooth muscle proliferation.

PubMed

Chalmers, Susan; Saunter, Christopher; Wilson, Calum; Coats, Paul; Girkin, John M; McCarron, John G

2012-12-01

Mitochondria are widely described as being highly dynamic and adaptable organelles, and their movement is thought to be vital for cell function. Yet, in various native cells, including those of heart and smooth muscle, mitochondria are stationary and rigidly structured. The significance of the differences in mitochondrial behavior to the physiological function of cells is unclear and was studied in single myocytes and intact resistance-sized cerebral arteries. We hypothesized that mitochondrial dynamics is controlled by the proliferative status of the cells. High-speed fluorescence imaging of mitochondria in live vascular smooth muscle cells shows that the organelle undergoes significant reorganization as cells become proliferative. In nonproliferative cells, mitochondria are individual (≈ 2 μm by 0.5 μm), stationary, randomly dispersed, fixed structures. However, on entering the proliferative state, mitochondria take on a more diverse architecture and become small spheres, short rod-shaped structures, long filamentous entities, and networks. When cells proliferate, mitochondria also continuously move and change shape. In the intact pressurized resistance artery, mitochondria are largely immobile structures, except in a small number of cells in which motility occurred. When proliferation of smooth muscle was encouraged in the intact resistance artery, in organ culture, the majority of mitochondria became motile and the majority of smooth muscle cells contained moving mitochondria. Significantly, restriction of mitochondrial motility using the fission blocker mitochondrial division inhibitor prevented vascular smooth muscle proliferation in both single cells and the intact resistance artery. These results show that mitochondria are adaptable and exist in intact tissue as both stationary and highly dynamic entities. This mitochondrial plasticity is an essential mechanism for the development of smooth muscle proliferation and therefore presents a novel therapeutic target against vascular disease.

Morpho-functional evaluation of small bowel using wireless motility capsule and video capsule endoscopy in patients with known or suspected Crohn's disease: pilot study.

PubMed

Yung, Diana; Douglas, Sarah; Hobson, Anthony R; Giannakou, Andry; Plevris, John N; Koulaouzidis, Anastasios

2016-04-01

SmartPill(®) (Given Imaging Corp.,Yoqneam,Israel) is an ingestible, non-imaging capsule that records physiological data including contractions and pH throughout the gastrointestinal tract. There are scarce data looking at SmartPill(®) assessment of patients with known/suspected small-bowel Crohn's Disease (CD). This pilot study aims to investigate feasibility and safety of SmartPill(®) to assess gut motility in this group.  Over 1 year, patients with known/suspected CD, referred for small-bowel capsule endoscopy (SBCE), were invited to participate and 12 were recruited (7 female, 5 male, mean age 44.2 ± 16.6 years). They underwent hydrogen breath test to exclude small-bowel bacterial overgrowth, patency capsule (Agile(®)), and provided stool samples for fecal calprotectin (FC). Patients ingested PillCam(®)SB2 and SmartPill(®) 4 hours apart. Using unpublished data, 33 healthy controls also were identified for the study. P < 0.05 was considered statistically significant. Of the 12 patients enrolled, 10 underwent complete Smartpill(®) examination (1 stomach retention, 1 dropout). Pillcam(®) was complete in 10 (1 dropout, 1 stomach retention). Mean fecal calprotectin was 340 ± 307.71 mcg/g. The study group had longer transit times and lower gut motility index than did the controls. The difference in motility appears to be statistically significant (P < 0.05). Longer transit times for SmartPill(®) (not statistically significant) may have been due to different specifications between the capsules. Limitations included transient Smartpill(®) signal loss (5/10 studies). This is the first pilot to attempt combining SBCE and SmartPill(®) to assess small-bowel CD. Data on motility in CD are scarce. Multimodal information can provide a clearer clinical picture. Despite concerns about capsule retention in CD patients, SmartPill(®) seems safe for use if a patency capsule is employed beforehand.

[Effects of biologically active pectin-containing dietary supplement on gastroduodenal motility in patients with a functional dyspepsia].

PubMed

Loranskaia, T I; Kabanova, I N; Klykova, E V

2002-01-01

For 21 patients with a functional dyspepsia the influencing biologically active additives to nutrition "Pekcecom" on dynamics of clinical symptoms and parameters gastroduodenal motility under the data gastroduodenoscintigraphy was studied. The usage of biologically active additives during 4 weeks was accompanied by deboosting of accelerated gastric emptying for want of statistically significant influencing on a normal and delayed gastric emptying and parameters of duodenal transit.

Fertilization of sea urchin eggs and sperm motility are negatively impacted under low hypergravitational forces significant to space flight

NASA Technical Reports Server (NTRS)

Tash, J. S.; Kim, S.; Schuber, M.; Seibt, D.; Kinsey, W. H.

2001-01-01

Sperm and other flagellates swim faster in microgravity (microG) than in 1 G, raising the question of whether fertilization is altered under conditions of space travel. Such alterations have implications for reproduction of plant and animal food and for long-term space habitation by man. We previously demonstrated that microG accelerates protein phosphorylation during initiation of sperm motility but delays the sperm response to the egg chemotactic factor, speract. Thus sperm are sensitive to changes in gravitational force. New experiments using the NiZeMi centrifugal microscope examined whether low hypergravity (hyperG) causes effects opposite to microG on sperm motility, signal transduction, and fertilization. Sperm % motility and straight-line velocity were significantly inhibited by as little as 1.3 G. The phosphorylation states of FP130, an axonemal phosphoprotein, and FP160, a cAMP-dependent salt-extractable flagellar protein, both coupled to motility activation, showed a more rapid decline in hyperG. Most critically, hyperG caused an approximately 50% reduction in both the rate of sperm-egg binding and fertilization. The similar extent of inhibition of both fertilization parameters in hyperG suggests that the primary effect is on sperm rather than eggs. These results not only support our earlier microG data demonstrating that sperm are sensitive to small changes in gravitational forces but more importantly now show that this sensitivity affects the ability of sperm to fertilize eggs. Thus, more detailed studies on the impact of space flight on development should include studies of sperm function and fertilization.

Comparison of cryopreserved human sperm in vapor and liquid phases of liquid nitrogen: effect on motility parameters, morphology, and sperm function.

PubMed

Punyatanasakchai, Piyaphan; Sophonsritsuk, Areephan; Weerakiet, Sawaek; Wansumrit, Surapee; Chompurat, Deonthip

2008-11-01

To compare the effects of cryopreserved sperm in vapor and liquid phases of liquid nitrogen on sperm motility, morphology, and sperm function. Experimental study. Andrology laboratory at Ramathibodi Hospital, Thailand. Thirty-eight semen samples with normal motility and sperm count were collected from 38 men who were either patients of an infertility clinic or had donated sperm for research. Each semen sample was divided into two aliquots. Samples were frozen with static-phase vapor cooling. One aliquot was plunged into liquid nitrogen (-196 degrees C), and the other was stored in vapor-phase nitrogen (-179 degrees C) for 3 days. Thawing was performed at room temperature. Motility was determined by using computer-assisted semen analysis, sperm morphology was determined by using eosin-methylene blue staining, and sperm function was determined by using a hemizona binding test. Most of the motility parameters of sperm stored in the vapor phase were not significantly different from those stored in the liquid phase of liquid nitrogen, except in amplitude of lateral head displacement. The percentages of normal sperm morphology in both vapor and liquid phases also were not significantly different. There was no significant difference in the number of bound sperm in hemizona between sperm cryopreserved in both vapor and liquid phases of liquid nitrogen. Cryopreservation of human sperm in a vapor phase of liquid nitrogen was comparable to cryopreservation in a liquid phase of liquid nitrogen.

Improvement of gastric motility by hemodialysis in patients with chronic renal failure.

PubMed

Adachi, Hiroshi; Kamiya, Takeshi; Hirako, Makoto; Misu, Naoko; Kobayashi, Yuka; Shikano, Michiko; Matsuhisa, Eriko; Kataoka, Hiromi; Sasaki, Makoto; Ohara, Hirotaka; Nakao, Haruhisa; Orito, Etsuro; Joh, Takashi

2007-10-01

Gastrointestinal (GI) symptoms are common in patients with chronic renal failure (CRF). We have previously demonstrated that patients with predialysis end-stage renal disease showed a high prevalence of GI symptoms and gastric hypomotility, and that gastric hypomotility appears to be an important factor in generating GI symptoms. However, it is not clear whether impaired gastric motor function would improve after hemodialytic treatment. To examine the relationship between gastric motor function and GI symptoms in CRF patients on hemodialysis. The study was performed in 19 patients with CRF treated with hemodialysis for more than six months and in 12 matched healthy controls. GI symptom severity was quantified in all patients. Gastric motility was evaluated with cutaneously recorded electrogastrography (EGG) and gastric emptying of semi-solid meals using the (13)C-acetic acid breath test. Six patients had no symptoms, and 11 had slight GI symptoms with a total symptom score of less than 5. Compared with controls, CRF patients revealed no differences in gastric motility parameters, with the exception of a lower percentage of normogastria in EGG at fasting state. Eleven patients had normal gastric motor function (Group A), and eight showed abnormalities of either gastric myoelectrical activity or gastric emptying (Group B). There was no difference in symptom score between Group A and Group B. More than half of the patients with CRF on hemodialysis demonstrated normal gastric motility, and no or slight GI symptoms. Hemodialytic treatment may improve impaired gastric motility and reduce GI symptoms in patients with CRF.

Relationship between Porcine Sperm Motility and Sperm Enzymatic Activity using Paper-based Devices

NASA Astrophysics Data System (ADS)

Matsuura, Koji; Huang, Han-Wei; Chen, Ming-Cheng; Chen, Yu; Cheng, Chao-Min

2017-04-01

Mammalian sperm motility has traditionally been analyzed to determine fertility using computer-assisted semen analysis (CASA) systems. To develop low-cost and robust male fertility diagnostics, we created a paper-based MTT assay and used it to estimate motile sperm concentration. When porcine sperm motility was inhibited using sperm enzyme inhibitors for sperm enzymes related to mitochondrial activity and glycolysis, we simultaneously recorded sperm motility and enzymatic reactivity using a portable motility analysis system (iSperm) and a paper-based MTT assay, respectively. When using our paper-based MTT-assay, we calculated the area mean value signal intensity (AMV) to evaluate enzymatic reactivity. Both sperm motility and AMV decreased following treatment with iodoacetamide (IODO) and 3-bromopyruvic acid (3BP), both of which are inhibitors of glycolytic enzymes including glyceraldehyde-3-phosphate dehydrogenase (GAPDH). We found a correlation between recorded motility using iSperm and AMV from our paper-based assay (P < 0.05), suggesting that a sperm-related enzymatic reaction is involved in sperm motility. Under this protocol, MTT reduction was coupled with catalysis of GAPDH and was promoted by electron transfer from NADH. Based on this inhibitor study, sperm motility can be estimated using our paper-based MTT-assay.

Actin motility: formin a SCAry tail.

PubMed

Alberts, Art; Way, Michael

2011-01-11

A new biochemical analysis has revealed that the Rickettsia bacterial protein Sca2--recently shown to be essential for virulence and actin-dependent motility--assembles actin filaments using a mechanism that functionally resembles the processive elongation tactics used by formins. Copyright © 2011 Elsevier Ltd. All rights reserved.

Exploratory Research on Latent Esophageal Motility Disorders in Dysphagia Patients.

PubMed

Kawaguchi, Shinpei; Takeuchi, Toshihisa; Inoue, Yousuke; Takahashi, Yoshiaki; Ozaki, Haruhiko; Ota, Kazuhiro; Harada, Satoshi; Edogawa, Shoko; Kojima, Yuichi; Yamashita, Hiroshi; Fukuchi, Takumi; Ashida, Kiyoshi; Higuchi, Kazuhide

2017-01-01

High-resolution manometry (HRM) has been applied to assess esophageal motility disorders. However, the frequency and types of motility disorders in patients with dysphagia, which are frequently seen in clinical practice, are not clear. We evaluated latent esophageal motility disorders associated with dysphagia. The study included patients without erosive esophageal mucosal damage and with dysphagia symptoms refractory to at least 8 weeks of standard-dose proton pump inhibitors. After enrolment, HRM was used to evaluate for esophageal motility disorder based on the Chicago classification. Esophageal motility disorder was found in 58 of 100 patients and was classified based on the causes: achalasia (13%), esophagogastric junction outflow obstruction (16%), distal esophageal spasms (3%), weak peristalsis (14%), frequently failed peristalsis (5%), and hypertensive peristalsis (7%). Primary esophageal motility disorder was found in approximately 50% of cases in dysphagia patients. Therefore, esophageal motility disorder is not an uncommon condition and should be sought for in order to elucidate precisely the cause of dysphagia. © 2017 S. Karger AG, Basel.

Multiscale Characterization of Bacterial Swarming Illuminates Principles Governing Directed Surface Motility

NASA Astrophysics Data System (ADS)

Strickland, Ben; Hoeger, Kentaro; Ursell, Tristan

In many systems, individual characteristics interact, leading to the spontaneous emergence of order and complexity. In biological settings like microbes, such collective behaviors can imbue a variety of benefits to constituent individuals, including increased spatial range, improved access to nutrients, and enhanced resistance to antibiotic threats. To untangle the biophysical underpinnings of collective motility, we use passive tracers and a curated genetic library of Bacillus subtilis, including motile, non-motile, biofilm-deficient, and non-chemotactic mutants. We characterize and connect individual behavior on the microscopic scale to macroscopic colony morphology and motility of dendritic swarming. We analyze the persistence and dynamics of coordinated movement on length scales up to 4 orders of magnitude larger than that of individual cells, revealing rapid and directed responses of microbial groups to external stimuli, such as avoidance dynamics across chemical gradients. Our observations uncover the biophysical interplay between individual motility, surface wetness, phenotypic diversity, and external physical forces that robustly precipitate coordinated group behavior in microbes, and suggest general principles that govern the transition from individual to group behavior.

Fungal networks shape dynamics of bacterial dispersal and community assembly in cheese rind microbiomes.

PubMed

Zhang, Yuanchen; Kastman, Erik K; Guasto, Jeffrey S; Wolfe, Benjamin E

2018-01-23

Most studies of bacterial motility have examined small-scale (micrometer-centimeter) cell dispersal in monocultures. However, bacteria live in multispecies communities, where interactions with other microbes may inhibit or facilitate dispersal. Here, we demonstrate that motile bacteria in cheese rind microbiomes use physical networks created by filamentous fungi for dispersal, and that these interactions can shape microbial community structure. Serratia proteamaculans and other motile cheese rind bacteria disperse on fungal networks by swimming in the liquid layers formed on fungal hyphae. RNA-sequencing, transposon mutagenesis, and comparative genomics identify potential genetic mechanisms, including flagella-mediated motility, that control bacterial dispersal on hyphae. By manipulating fungal networks in experimental communities, we demonstrate that fungal-mediated bacterial dispersal can shift cheese rind microbiome composition by promoting the growth of motile over non-motile community members. Our single-cell to whole-community systems approach highlights the interactive dynamics of bacterial motility in multispecies microbiomes.

Alteration of sperm quality and hormone levels by polycyclic aromatic hydrocarbons on airborne particulate particles.

PubMed

Jeng, Hueiwang Anna; Yu, Liang

2008-06-01

The objective of this study was to assess whether polycyclic aromatic hydrocarbons (PAHs) affect male reproductive functions in vivo. Male reproductive parameters included testis weight, sperm counts and motility, circulating follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. The average body weight, testis weight, and epididymis weight in the exposed group were not significantly lower than that in the control group (p < 0.01). The daily numbers of sperm in the PAH-exposed groups were significantly lower than those in the control group. The motility of sperm in the PAH-exposed groups was significantly less than those in the control group. Plasma LH concentrations increased at the end of the exposure period and continued to increase after post-cessation of exposure to PAHs. Testosterone decreased at the end of the exposure period and increased after post-cessation of exposure. However, the follicle-stimulation hormone level remained relatively stable during the study period. The present study showed that PAHs can compromise sperm functions and alter endocrine hormone levels.

Actin Depolymerizing Factor (ADF/Cofilin) Enhances the Rate of Filament Turnover: Implication in Actin-based Motility

PubMed Central

Carlier, Marie-France; Laurent, Valérie; Santolini, Jérôme; Melki, Ronald; Didry, Dominique; Xia, Gui-Xian; Hong, Yan; Chua, Nam-Hai; Pantaloni, Dominique

1997-01-01

Actin-binding proteins of the actin depolymerizing factor (ADF)/cofilin family are thought to control actin-based motile processes. ADF1 from Arabidopsis thaliana appears to be a good model that is functionally similar to other members of the family. The function of ADF in actin dynamics has been examined using a combination of physical–chemical methods and actin-based motility assays, under physiological ionic conditions and at pH 7.8. ADF binds the ADPbound forms of G- or F-actin with an affinity two orders of magnitude higher than the ATP- or ADP-Pi– bound forms. A major property of ADF is its ability to enhance the in vitro turnover rate (treadmilling) of actin filaments to a value comparable to that observed in vivo in motile lamellipodia. ADF increases the rate of propulsion of Listeria monocytogenes in highly diluted, ADF-limited platelet extracts and shortens the actin tails. These effects are mediated by the participation of ADF in actin filament assembly, which results in a change in the kinetic parameters at the two ends of the actin filament. The kinetic effects of ADF are end specific and cannot be accounted for by filament severing. The main functionally relevant effect is a 25-fold increase in the rate of actin dissociation from the pointed ends, while the rate of dissociation from the barbed ends is unchanged. This large increase in the rate-limiting step of the monomer-polymer cycle at steady state is responsible for the increase in the rate of actin-based motile processes. In conclusion, the function of ADF is not to sequester G-actin. ADF uses ATP hydrolysis in actin assembly to enhance filament dynamics. PMID:9087445

Differential KrasV12 protein levels control a switch regulating lung cancer cell morphology and motility

PubMed Central

Schäfer, C.; Mohan, A.; Burford, W.; Driscoll, M. K.; Ludlow, A. T.; Wright, W. E.; Shay, J. W.; Danuser, G.

2016-01-01

Introduction Oncogenic Kras mutations are important drivers of lung cancer development and metastasis. They are known to activate numerous cellular signaling pathways implicated in enhanced proliferation, survival, tumorigenicity and motility during malignant progression. Objectives Most previous studies of Kras in cancer have focused on the comparison of cell states in the absence or presence of oncogenic Kras mutations. Here we show that differential expression of the constitutively active mutation KrasV12 has profound effects on cell morphology and motility that drive metastatic processes. Methods The study relies on lung cancer cell transformation models, patient-derived lung cancer cell lines, and human lung tumor sections combined with molecular biology techniques, live-cell imaging and staining methods. Results Our analysis shows two cell functional states driven by KrasV12 protein levels: a non-motile state associated with high KrasV12 levels and tumorigenicity, and a motile state associated with low KrasV12 levels and cell dissemination. Conversion between the states is conferred by differential activation of a mechano-sensitive double-negative feedback between KrasV12/ERK/Myosin II and matrix-adhesion signaling. KrasV12 expression levels change upon cues such as hypoxia and integrin-mediated cell-matrix adhesion, rendering KrasV12 levels an integrator of micro-environmental signals that translate into cellular function. By live cell imaging of tumor models we observe shedding of mixed high and low KrasV12 expressers forming multi-functional collectives with potentially optimal metastatic properties composed of a highly mobile and a highly tumorigenic unit. Discussion Together these data highlight previously unappreciated roles for the quantitative effects of expression level variation of oncogenic signaling molecules in conferring fundamental alterations in cell function regulation required for cancer progression. PMID:29057096

Association of seminal plasma motility inhibitors/semenogelins with sperm in asthenozoospermia-infertile men.

PubMed

Terai, K; Yoshida, K; Yoshiike, M; Fujime, M; Iwamoto, T

2010-01-01

Seminal plasma motility inhibitors (SPMIs) are proteinase-resistant fragments of semenogelin I and II (Sgs), which are the major proteins of semen coagulum. SPMIs inhibit the motility of spermatozoa, and Sgs are thought to be natural regulators of human sperm function. The mechanism underlying sperm motility regulation and its association with defective motility in infertile men remain unclear. The purpose of this study was to investigate the association between SPMIs and spermatozoa in infertile men with asthenozoospermia. Fifty-four semen samples from 37 asthenozoospermic patients and 17 samples from 9 normal healthy subjects were analyzed. Spermatozoa, washed by Percoll density gradients, were immunostained with anti-SPMI antibody and subjected to flow cytometric analysis. The proportion of spermatozoa labeled with the antibody and the average intensity of fluorescence labeling per spermatozoa were analyzed in relation to the parameters used for semen analysis. A significant negative correlation was found between sperm motility and the proportion (R = -0.68) and intensity (R = -0.38) of labeling. These results suggest that SPMIs remain on the sperm surface after liquefaction. This might account for some disorders of sperm motility observed in infertile men with asthenozoospermia. Copyright © 2010 S. Karger AG, Basel.

Recording In Vivo Human Colonic Motility: What Have We Learnt Over the Past 100 Years?

PubMed

Dinning, Phil G

To understand the abnormalities that underpin functional gut disorders we must first gain insight into the normal patterns of gut motility. While detailed information continually builds on the motor patterns (and mechanisms that control them) of the human esophagus and anorectum, our knowledge of normal and abnormal motility in the more inaccessible regions of the gut remains poor. This particularly true of the human colon. Investigation of in vivo colonic motor patterns is achieved through measures of transit (radiology, scintigraphy and, more recently, "smart pills") or by direct real-time recording of colonic contractility (intraluminal manometry). This short review will provide an overview of findings from the past and present and attempt to piece together the complex nature of colonic motor patterns. In doing so it will build a profile of human colonic motility and determine the likely mechanisms that control this motility.

International review of cytology. Volume 109: A survey of cell biology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bourne, G.; Jeon, K.W.; Friedlander, M.

1987-01-01

This book's contents are: Local Regulation of Testicular Function;Microtubules and DNA Replication;Differentiation of Spermatogenic Cells from Vertebrates in Vitro;The Developmental Program of Spermiogenesis in Drosophila: A Genetic Analysis;Cell Motility and Ionic Relations in Characean Cells as Revealed by Internal Perfusion and Other Cell Models;and The Culture of Oral Epithelium. Each chapter includes references.

Group management influences reproductive function of the male cheetah (Acinonyx jubatus).

PubMed

Koester, Diana C; Freeman, Elizabeth W; Wildt, David E; Terrell, Kimberly A; Franklin, Ashley D; Meeks, Karen; Crosier, Adrienne E

2017-03-01

Although the free-ranging cheetah is generally socially solitary, as many as 60% of males live in same-sex (usually sibling) coalitions. Under ex situ conditions, the cheetah experiences low reproductive success with only ~18% of males having ever produced young. Most male cheetahs (85%) are managed in captivity in coalitions, but with no data on the influence of social grouping on reproductive parameters. We examined the influence of singleton versus coalition management on various male cheetah physiological traits, including ejaculate quality and gonadal and adrenal hormone metabolite concentrations. We also assessed behaviour within coalitions for evidence of social hierarchy through initiation of interactions with group mates and relatedness to physiological traits. Ejaculate quality (including total motile and structurally normal spermatozoa per ejaculate) and androgen concentration profiles were higher (P<0.05) in coalition compared with singleton males. These results support the conclusion that testis function in the cheetah, specifically related to the development of normal, motile spermatozoa and androgen production, is influenced by management with same-sex conspecifics. The findings have implications for ex situ conservation breeding programs by suggesting that reproductive quality can be enhanced through group maintenance of cheetah males.

Pac-man motility of kinetochores unleashed by laser microsurgery

PubMed Central

LaFountain, James R.; Cohan, Christopher S.; Oldenbourg, Rudolf

2012-01-01

We report on experiments directly in living cells that reveal the regulation of kinetochore function by tension. X and Y sex chromosomes in crane fly (Nephrotoma suturalis) spermatocytes exhibit an atypical segregation mechanism in which each univalent maintains K-fibers to both poles. During anaphase, each maintains a leading fiber (which shortens) to one pole and a trailing fiber (which elongates) to the other. We used this intriguing behavior to study the motile states that X-Y kinetochores are able to support during anaphase. We used a laser microbeam to either sever a univalent along the plane of sister chromatid cohesion or knock out one of a univalent's two kinetochores to release one or both from the resistive influence of its sister's K-fiber. Released kinetochores with attached chromosome arms moved poleward at rates at least two times faster than normal. Furthermore, fluorescent speckle microscopy revealed that detached kinetochores converted their functional state from reverse pac-man to pac-man motility as a consequence of their release from mechanical tension. We conclude that kinetochores can exhibit pac-man motility, even though their normal behavior is dominated by traction fiber mechanics. Unleashing of kinetochore motility through loss of resistive force is further evidence for the emerging model that kinetochores are subject to tension-sensitive regulation. PMID:22740625

Motility of Pseudomonas aeruginosa contributes to SOS-inducible biofilm formation.

PubMed

Chellappa, Shakinah T; Maredia, Reshma; Phipps, Kara; Haskins, William E; Weitao, Tao

2013-12-01

DNA-damaging antibiotics such as ciprofloxacin induce biofilm formation and the SOS response through autocleavage of SOS-repressor LexA in Pseudomonas aeruginosa. However, the biofilm-SOS connection remains poorly understood. It was investigated with 96-well and lipid biofilm assays. The effects of ciprofloxacin were examined on biofilm stimulation of the SOS mutant and wild-type strains. The stimulation observed in the wild-type in which SOS was induced was reduced in the mutant in which LexA was made non-cleavable (LexAN) and thus SOS non-inducible. Therefore, the stimulation appeared to involve SOS. The possible mechanisms of inducible biofilm formation were explored by subproteomic analysis of outer membrane fractions extracted from biofilms. The data predicted an inhibitory role of LexA in flagellum function. This premise was tested first by functional and morphological analyses of flagellum-based motility. The flagellum swimming motility decreased in the LexAN strain treated with ciprofloxacin. Second, the motility-biofilm assay was performed, which tested cell migration and biofilm formation. The results showed that wild-type biofilm increased significantly over the LexAN. These results suggest that LexA repression of motility, which is the initial event in biofilm development, contributes to repression of SOS-inducible biofilm formation. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Autophagy-related proteins are functionally active in human spermatozoa and may be involved in the regulation of cell survival and motility

PubMed Central

Aparicio, I. M.; Espino, J.; Bejarano, I.; Gallardo-Soler, A.; Campo, M. L.; Salido, G. M.; Pariente, J. A.; Peña, F. J.; Tapia, J. A.

2016-01-01

Macroautophagy (hereafter autophagy) is an evolutionarily highly conserved cellular process that participates in the maintenance of intracellular homeostasis through the degradation of most long-lived proteins and entire organelles. Autophagy participates in some reproductive events; however, there are not reports regarding the role of autophagy in the regulation of sperm physiology. Hence, the aim of this study was to investigate whether autophagy-related proteins are present and functionally active in human spermatozoa. Proteins related to autophagy/mitophagy process (LC3, Atg5, Atg16, Beclin 1, p62, m-TOR, AMPKα 1/2, and PINK1) were present in human spermatozoa. LC3 colocalized with p62 in the middle piece of the spermatozoa. Autophagy activation induced a significant increase in motility and a decrease in PINK1, TOM20 expression and caspase 3/7 activation. In contrast, autophagy inhibition resulted in decreased motility, viability, ATP and intracellular calcium concentration whereas PINK1, TOM20 expression, AMPK phosphorylation and caspase 3/7 activation were significantly increased. In conclusion our results show that autophagy related proteins and upstream regulators are present and functional in human spermatozoa. Modification of mitochondrial proteins expression after autophagy activation/inhibition may be indicating that a specialized form of autophagy named mitophagy may be regulating sperm function such as motility and viability and may be cooperating with apoptosis. PMID:27633131

The flagellum of Trypanosoma brucei: new tricks from an old dog

PubMed Central

Ralston, Katherine S.; Hill, Kent L.

2010-01-01

African trypanosomes, i.e. Trypanosoma brucei and related sub-species, are devastating human and animal pathogens that cause significant human mortality and limit sustained economic development in sub-Saharan Africa. Trypanosoma brucei is a highly motile protozoan parasite and coordinated motility is central to both disease pathogenesis in the mammalian host and parasite development in the tsetse fly vector. Since motility is critical for parasite development and pathogenesis, understanding unique aspects of the T. brucei flagellum may uncover novel targets for therapeutic intervention in African sleeping sickness. Moreover, studies of conserved features of the T. brucei flagellum are directly relevant to understanding fundamental aspects of flagellum and cilium function in other eukaryotes, making T. brucei an important model system. The T. brucei flagellum contains a canonical 9 + 2 axoneme, together with additional features that are unique to kinetoplastids and a few closely-related organisms. Until recently, much of our knowledge of the structure and function of the trypanosome flagellum was based on analogy and inference from other organisms. There has been an explosion in functional studies in T. brucei in recent years, revealing conserved as well as novel and unexpected structural and functional features of the flagellum. Most notably, the flagellum has been found to be an essential organelle, with critical roles in parasite motility, morphogenesis, cell division and immune evasion. This review highlights recent discoveries on the T. brucei flagellum. PMID:18472102

Screen for Slit/Robo signaling in trunk neural cells reveals new players.

PubMed

Martinez, Darwin; Zuhdi, Nora; Reyes, Michelle; Ortega, Blanca; Giovannone, Dion; Lee, Vivian M; de Bellard, Maria Elena

2018-06-01

Slits ligands and their Robo receptors are involved in quite disparate cell signaling pathways that include axon guidance, cell proliferation, cell motility and angiogenesis. Neural crest cells emerge by delamination from neural cells in the dorsal neural tube, and give rise to various components of the peripheral nervous system in vertebrates. It is well established that these cells change from a non-migratory to a highly migratory state allowing them to reach distant regions before they differentiate. However, but the mechanism controlling this delamination and subsequent migration are still not fully understood. The repulsive Slit ligand family members, have been classified also as true tumor suppressor molecules. The present study explored in further detail what possible Slit/Robo signals are at play in the trunk neural cells and neural crest cells by carrying out a microarray after Slit2 gain of function in trunk neural tubes. We found that in addition to molecules known to be downstream of Slit/Robo signaling, there were a large set of molecules known to be important in maintaining cells in non-motile, epithelia phenotype. Furthermore, we found new molecules previously not associated with Slit/Robo signaling: cell proliferation markers, Ankyrins and RAB intracellular transporters. Our findings suggest that neural crest cells use and array of different Slit/Robo pathways during their transformation from non-motile to highly motile cells. Copyright © 2018. Published by Elsevier B.V.

Vision related quality of life in spinocerebellar ataxia.

PubMed

Kedar, Sachin; Ghate, Deepta; Murray, Earnest L; Corbett, James J; Subramony, S H

2015-11-15

Spinocerebellar ataxia (SCA) leads to abnormal ocular motility and alignment. The objective of this study was to quantitatively assess vision, ocular motility and alignment and its impact on vision related quality of life (VRQOL) in SCA. Nineteen genetically diagnosed SCA subjects (11 SCA type 3, 3 SCA type 1 and 5 SCA type 6) participated at two university centers. All subjects completed the National Eye Institute Visual Function Questionnaire (NEI-VFQ), 10-Item Neuro-Ophthalmic Supplement (NOS), scale for assessment and rating of ataxia (SARA) and ophthalmic examination. Twelve subjects seen at one of the 2 sites underwent quantitative ocular motility and alignment assessment. Composite scores for NEI-VFQ (mean 76.3±13) and NOS (mean 65.2±16.8) were significantly decreased in SCA subjects. NEI-VFQ subscale scores were decreased for general, near, distance and peripheral vision and driving. SCA patients had decreased low contrast sensitivity, stereoacuity and multiple ocular motility defects which included gaze limitation (9/12), nystagmus (5/12), distance esophoria (11/12), near exophoria (12/12) and receded near point of convergence. A significant negative correlation was noted between composite scores and distance convergence fusional amplitude. VRQOL is significantly decreased in SCA compared to normal population. All SCA patients should be screened for visual disability and referred for neuro-ophthalmic assessment promptly. Copyright © 2015 Elsevier B.V. All rights reserved.

The Role of Esophageal Hypersensitivity in Functional Esophageal Disorders.

PubMed

Farmer, Adam D; Ruffle, James K; Aziz, Qasim

2017-02-01

The Rome IV diagnostic criteria delineates 5 functional esophageal disorders which include functional chest pain, functional heartburn, reflux hypersensitivity, globus, and functional dysphagia. These are a heterogenous group of disorders which, despite having characteristic symptom profiles attributable to esophageal pathology, fail to demonstrate any structural, motility or inflammatory abnormalities on standard clinical testing. These disorders are associated with a marked reduction in patient quality of life, not least considerable healthcare resources. Furthermore, the pathophysiology of these disorders is incompletely understood. In this narrative review we provide the reader with an introductory primer to the structure and function of esophageal perception, including nociception that forms the basis of the putative mechanisms that may give rise to symptoms in functional esophageal disorders. We also discuss the provocative techniques and outcome measures by which esophageal hypersensitivity can be established.

The Janus-faced role of ezrin in "linking" cells to either normal or metastatic phenotype.

PubMed

Brambilla, Daria; Fais, Stefano

2009-11-15

In the majority of eukaryotic cells, the ezrin, radixin and moesin (ERM) proteins are involved in many physiologic functions including regulation of actin cytoskeleton, control of cell shape, adhesion, motility and modulation of signal transduction pathways. In a previous study, we used a dominant negative ezrin-mutant to address ezrin involvement in remodeling of actin cytoskeleton and subsequently we depicted ezrin key role in melanoma cell migration and progression. Herein, we highlight recent advances on ezrin involvement in the metastatic phenomenon, including also some more neglected ezrin-related functions. Novel molecular processes driven by ezrin activation include: phagocytosis, acquisition of resistance to chemotherapeutics and triggering of programmed cell death signals. Recent data support an integrated role of ezrin also in development of tumor malignancy. On one hand, ezrin may be responsible of deranged execution of specific known functions such as adhesion and motility and on the other, it may also participate to unique metastatic determinants, through the establishment of aberrant linkages with tumor-related proteins. For instance, ezrin misslocalization, absence or deranged activity has started to be correlated with tumor progression in many tumors of different species, including humans. Concomitantly, ezrin may act simultaneously as a regulatory or deregulatory chaperon in both normal and tumor cells. It is still to be established whether this Janus-faced feature of ezrin is due to some unknown transforming Zelig-like property or to the fact that a tumor-associated molecule preferentially links to ezrin thus distracting it from its normal connections. However, the contribution of ezrin functional deregulation to the acquisition of the metastatic phenotype appears clear and ezrin or ezrin aberrant associations may represent good candidates for future anti-tumor therapies.

Soy lecithin interferes with mitochondrial function in frozen-thawed ram spermatozoa.

PubMed

Del Valle, I; Gómez-Durán, A; Holt, W V; Muiño-Blanco, T; Cebrián-Pérez, J A

2012-01-01

Egg yolk and milk are the 2 major membrane cryoprotectants commonly used in freezing media for the long-term preservation of semen (alone or in combination with others). However, in recent years, there have been increasing arguments against the use of egg yolk or milk because of the risk of introducing diseases through the use of cryopreserved semen. In this study, we analyzed the protective effect of lecithin as an alternative to egg yolk for the cryopreservation of ram semen, using a range of functional markers for sperm viability, motility, apoptosis, and mitochondrial functionality analyses (mitochondrial inner membrane surface [MIMS], mitochondrial inner membrane potential [MIMP], and cell membrane potential) as methods of assessment in samples diluted in 3 different media: Tris-citrate-glucose as control and 2 media supplemented with soy lecithin or egg yolk. The results showed that lecithin was able to effectively protect certain sperm quality characteristics against freezing-induced damage. However, lecithin induced loss of mitochondrial membrane potential or mitochondrial loss that was not reflected by modifications in sperm motility in fresh semen. MIMS and MIMP values decreased in thawed lecithin-treated samples, concomitant with a lower (P < .05) percentage of total and progressively motile cells, compared with those in egg yolk-containing samples. Further incubation of thawed samples revealed changes in motility and mitochondrial functionality that otherwise would not have been detected. These results indicated that lecithin may have affected the inner mitochondrial membrane in frozenthawed spermatozoa and confirmed that sublethal damages that seriously affect sperm functionality, not detected by classic sperm quality analyses, can be evidenced by changes in the inner mitochondrial membrane surface. These findings strengthen the relationship between mitochondrial membrane potential and motility and show that the mitochondrial alterations induced by the cryopreservation process could be specific targets for the improvement of semen cryopreservation protocols.

Bidirectional motility of the fission yeast kinesin-5, Cut7

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edamatsu, Masaki, E-mail: cedam@mail.ecc.u-tokyo.ac.jp

Highlights: • Motile properties of Cut7 (fission yeast kinesin-5) were studied for the first time. • Half-length Cut7 moved toward plus-end direction of microtubule. • Full-length Cut7 moved toward minus-end direction of microtubule. • N- and C-terminal microtubule binding sites did not switch the motile direction. - Abstract: Kinesin-5 is a homotetrameric motor with its motor domain at the N-terminus. Kinesin-5 crosslinks microtubules and functions in separating spindle poles during mitosis. In this study, the motile properties of Cut7, fission yeast kinesin-5, were examined for the first time. In in vitro motility assays, full-length Cut7 moved toward minus-end of microtubules,more » but the N-terminal half of Cut7 moved toward the opposite direction. Furthermore, additional truncated constructs lacking the N-terminal or C-terminal regions, but still contained the motor domain, did not switch the motile direction. These indicated that Cut7 was a bidirectional motor, and microtubule binding regions at the N-terminus and C-terminus were not involved in its directionality.« less

On-command on/off switching of progenitor cell and cancer cell polarized motility and aligned morphology via a cytocompatible shape memory polymer scaffold.

PubMed

Wang, Jing; Quach, Andy; Brasch, Megan E; Turner, Christopher E; Henderson, James H

2017-09-01

In vitro biomaterial models have enabled advances in understanding the role of extracellular matrix (ECM) architecture in the control of cell motility and polarity. Most models are, however, static and cannot mimic dynamic aspects of in vivo ECM remodeling and function. To address this limitation, we present an electrospun shape memory polymer scaffold that can change fiber alignment on command under cytocompatible conditions. Cellular response was studied using the human fibrosarcoma cell line HT-1080 and the murine mesenchymal stem cell line C3H/10T1/2. The results demonstrate successful on-command on/off switching of cell polarized motility and alignment. Decrease in fiber alignment causes a change from polarized motility along the direction of fiber alignment to non-polarized motility and from aligned to unaligned morphology, while increase in fiber alignment causes a change from non-polarized to polarized motility along the direction of fiber alignment and from unaligned to aligned morphology. In addition, the findings are consistent with the hypothesis that increased fiber alignment causes increased cell velocity, while decreased fiber alignment causes decreased cell velocity. On-command on/off switching of cell polarized motility and alignment is anticipated to enable new study of directed cell motility in tumor metastasis, in cell homing, and in tissue engineering. Copyright © 2017 Elsevier Ltd. All rights reserved.

Swimming and twitching motility are essential for attachment and virulence of Pantoea ananatis in onion seedlings.

PubMed

Weller-Stuart, Tania; Toth, Ian; De Maayer, Pieter; Coutinho, Teresa

2017-06-01

Pantoea ananatis is a widespread phytopathogen with a broad host range. Despite its ability to infect economically important crops, such as maize, rice and onion, relatively little is known about how this bacterium infects and colonizes host tissue or spreads within and between hosts. To study the role of motility in pathogenicity, we analysed both swimming and twitching motility in P. ananatis LMG 20103. Genetic recombineering was used to construct four mutants affected in motility. Two flagellar mutants were disrupted in the flgK and motA genes, required for flagellar assembly and flagellar rotation, respectively. Similarly, two twitching motility mutants were generated, impaired in the structure (pilA) and functioning (pilT) of the type IV pili. The role of swimming and twitching motility during the infection cycle of P. ananatis in onion seedlings was determined by comparing the mutant- and wild-type strains using several in vitro and in planta assays. From the results obtained, it was evident that flagella aid P. ananatis in locating and attaching to onion leaf surfaces, as well as in pathogenicity, whereas twitching motility is instrumental in the spread of the bacteria on the surface once attachment has occurred. Both swimming and twitching motility contribute towards the ability of P. ananatis to cause disease in onions. © 2016 BSPP AND JOHN WILEY & SONS LTD.

Esophageal motility in eosinophilic esophagitis.

PubMed

Weiss, A H; Iorio, N; Schey, R

2015-01-01

Eosinophilic esophagitis (EoE) is characterized by eosinophilic infiltration of the esophagus and is a potential cause of dysphagia and food impaction, most commonly affecting young men. Esophageal manometry findings vary from normal motility to aperistalsis, simultaneous contractions, diffuse esophageal spasm, nutcracker esophagus or hypotonic lower esophageal sphincter (LES). It remains unclear whether esophageal dysmotility plays a significant role in the clinical symptoms of EoE. Our aim is to review the pathogenesis, diagnosis, and effect of treatment on esophageal dysmotility in EoE. A literature search utilizing the PubMed database was performed using keywords: eosinophilic esophagitis, esophageal dysmotility, motility, manometry, impedance planimetry, barium esophagogram, endoscopic ultrasound, and dysphagia. Fifteen studies, totaling 387 patients with eosinophilic esophagitis were identified as keeping in accordance with the aim of this study and included in this review. The occurrence of abnormal esophageal manometry was reported to be between 4 and 87% among patients with EoE. Esophageal motility studies have shown reduced distensibility, abnormal peristalsis, and hypotonicity of the LES in patients with EoE, which may also mimic other esophageal motility disorders such as achalasia or nutcracker esophagus. Studies have shown conflicting results regarding the presence of esophageal dysmotility and symptoms with some reports suggesting a higher rate of food impaction, while others report no correlation between motor function and dysphagia. Motility dysfunction of the esophagus in EoE has not been well reported in the literature and studies have reported conflicting evidence regarding the clinical significance of dysmotility seen in EoE. The correlation between esophageal dysmotility and symptoms of EoE remains unclear. Larger studies are needed to investigate the incidence of esophageal dysmotility, clinical implications, and effect of treatment on patients with EoE. Copyright © 2015 Asociación Mexicana de Gastroenterología. Published by Masson Doyma México S.A. All rights reserved.

Isolation of Salmonella mutants resistant to the inhibitory effect of Salicylidene acylhydrazides on flagella-mediated motility.

PubMed

Martinez-Argudo, Isabel; Veenendaal, Andreas K J; Liu, Xia; Roehrich, A Dorothea; Ronessen, Maria C; Franzoni, Giulia; van Rietschoten, Katerine N; Morimoto, Yusuke V; Saijo-Hamano, Yumiko; Avison, Matthew B; Studholme, David J; Namba, Keiichi; Minamino, Tohru; Blocker, Ariel J

2013-01-01

Salicylidene acylhydrazides identified as inhibitors of virulence-mediating type III secretion systems (T3SSs) potentially target their inner membrane export apparatus. They also lead to inhibition of flagellar T3SS-mediated swimming motility in Salmonella enterica serovar. Typhimurium. We show that INP0404 and INP0405 act by reducing the number of flagella/cell. These molecules still inhibit motility of a Salmonella ΔfliH-fliI-fliJ/flhB((P28T)) strain, which lacks three soluble components of the flagellar T3S apparatus, suggesting that they are not the target of this drug family. We implemented a genetic screen to search for the inhibitors' molecular target(s) using motility assays in the ΔfliH-fliI/flhB((P28T)) background. Both mutants identified were more motile than the background strain in the absence of the drugs, although HM18 was considerably more so. HM18 was more motile than its parent strain in the presence of both drugs while DI15 was only insensitive to INP0405. HM18 was hypermotile due to hyperflagellation, whereas DI15 was not hyperflagellated. HM18 was also resistant to a growth defect induced by high concentrations of the drugs. Whole-genome resequencing of HM18 indicated two alterations within protein coding regions, including one within atpB, which encodes the inner membrane a-subunit of the F(O)F(1)-ATP synthase. Reverse genetics indicated that the alteration in atpB was responsible for all of HM18's phenotypes. Genome sequencing of DI15 uncovered a single A562P mutation within a gene encoding the flagellar inner membrane protein FlhA, the direct role of which in mediating drug insensitivity could not be confirmed. We discuss the implications of these findings in terms of T3SS export apparatus function and drug target identification.

Compositional and expression analyses of the glideosome during the Plasmodium life cycle reveal an additional myosin light chain required for maximum motility

PubMed Central

Green, Judith L.; Wall, Richard J.; Vahokoski, Juha; Yusuf, Noor A.; Ridzuan, Mohd A. Mohd; Stanway, Rebecca R.; Stock, Jessica; Knuepfer, Ellen; Brady, Declan; Martin, Stephen R.; Howell, Steven A.; Pires, Isa P.; Moon, Robert W.; Molloy, Justin E.; Kursula, Inari; Tewari, Rita

2017-01-01

Myosin A (MyoA) is a Class XIV myosin implicated in gliding motility and host cell and tissue invasion by malaria parasites. MyoA is part of a membrane-associated protein complex called the glideosome, which is essential for parasite motility and includes the MyoA light chain myosin tail domain–interacting protein (MTIP) and several glideosome-associated proteins (GAPs). However, most studies of MyoA have focused on single stages of the parasite life cycle. We examined MyoA expression throughout the Plasmodium berghei life cycle in both mammalian and insect hosts. In extracellular ookinetes, sporozoites, and merozoites, MyoA was located at the parasite periphery. In the sexual stages, zygote formation and initial ookinete differentiation precede MyoA synthesis and deposition, which occurred only in the developing protuberance. In developing intracellular asexual blood stages, MyoA was synthesized in mature schizonts and was located at the periphery of segmenting merozoites, where it remained throughout maturation, merozoite egress, and host cell invasion. Besides the known GAPs in the malaria parasite, the complex included GAP40, an additional myosin light chain designated essential light chain (ELC), and several other candidate components. This ELC bound the MyoA neck region adjacent to the MTIP-binding site, and both myosin light chains co-located to the glideosome. Co-expression of MyoA with its two light chains revealed that the presence of both light chains enhances MyoA-dependent actin motility. In conclusion, we have established a system to study the interplay and function of the three glideosome components, enabling the assessment of inhibitors that target this motor complex to block host cell invasion. PMID:28893907

Compositional and expression analyses of the glideosome during the Plasmodium life cycle reveal an additional myosin light chain required for maximum motility.

PubMed

Green, Judith L; Wall, Richard J; Vahokoski, Juha; Yusuf, Noor A; Ridzuan, Mohd A Mohd; Stanway, Rebecca R; Stock, Jessica; Knuepfer, Ellen; Brady, Declan; Martin, Stephen R; Howell, Steven A; Pires, Isa P; Moon, Robert W; Molloy, Justin E; Kursula, Inari; Tewari, Rita; Holder, Anthony A

2017-10-27

Myosin A (MyoA) is a Class XIV myosin implicated in gliding motility and host cell and tissue invasion by malaria parasites. MyoA is part of a membrane-associated protein complex called the glideosome, which is essential for parasite motility and includes the MyoA light chain myosin tail domain-interacting protein (MTIP) and several glideosome-associated proteins (GAPs). However, most studies of MyoA have focused on single stages of the parasite life cycle. We examined MyoA expression throughout the Plasmodium berghei life cycle in both mammalian and insect hosts. In extracellular ookinetes, sporozoites, and merozoites, MyoA was located at the parasite periphery. In the sexual stages, zygote formation and initial ookinete differentiation precede MyoA synthesis and deposition, which occurred only in the developing protuberance. In developing intracellular asexual blood stages, MyoA was synthesized in mature schizonts and was located at the periphery of segmenting merozoites, where it remained throughout maturation, merozoite egress, and host cell invasion. Besides the known GAPs in the malaria parasite, the complex included GAP40, an additional myosin light chain designated essential light chain (ELC), and several other candidate components. This ELC bound the MyoA neck region adjacent to the MTIP-binding site, and both myosin light chains co-located to the glideosome. Co-expression of MyoA with its two light chains revealed that the presence of both light chains enhances MyoA-dependent actin motility. In conclusion, we have established a system to study the interplay and function of the three glideosome components, enabling the assessment of inhibitors that target this motor complex to block host cell invasion. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Actin-based motility of Listeria: Right-handed helical trajectories

NASA Astrophysics Data System (ADS)

Rangarajan, Murali

2012-06-01

Bacteria such as Listeria monocytogenes recruit cellular machinery to move in and between cells. Understanding the mechanism of motility, including force and torque generation and the resultant displacements, holds keys to numerous applications in medicine and biosensing. In this work, a simple back-of-the-envelope calculation is presented to illustrate that a biomechanical model of actin-based motility of a rigid surface through persistently attached filaments propelled by affinity-modulated molecular motors can produce a right-handed helical trajectory consistent with experimental observations. The implications of the mechanism to bacterial motility are discussed.

Lysophosphatidic acid signaling via LPA{sub 1} and LPA{sub 3} regulates cellular functions during tumor progression in pancreatic cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fukushima, Kaori; Takahashi, Kaede; Yamasaki, Eri

Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors exhibits a variety of biological effects, such as cell proliferation, motility and differentiation. The aim of this study was to evaluate the roles of LPA{sub 1} and LPA{sub 3} in cellular functions during tumor progression in pancreatic cancer cells. LPA{sub 1} and LPA{sub 3} knockdown cells were generated from PANC-1 cells. The cell motile and invasive activities of PANC-1 cells were inhibited by LPA{sub 1} and LPA{sub 3} knockdown. In gelatin zymography, LPA{sub 1} and LPA{sub 3} knockdown cells indicated the low activation of matrix metalloproteinase-2 (MMP-2) in the presence ofmore » LPA. Next, to assess whether LPA{sub 1} and LPA{sub 3} regulate cellular functions induced by anticancer drug, PANC-1 cells were treated with cisplatin (CDDP) for approximately 6 months. The cell motile and invasive activities of long-term CDDP treated cells were markedly higher than those of PANC-1 cells, correlating with the expression levels of LPAR1 and LPAR3 genes. In soft agar assay, the long-term CDDP treated cells formed markedly large sized colonies. In addition, the cell motile and invasive activities enhanced by CDDP were significantly suppressed by LPA{sub 1} and LPA{sub 3} knockdown as well as colony formation. These results suggest that LPA signaling via LPA{sub 1} and LPA{sub 3} play an important role in the regulation of cellular functions during tumor progression in PANC-1 cells. - Highlights: • The cell motile and invasive activities of PANC-1 cells were stimulated by LPA{sub 1} and LPA{sub 3}. • LPA{sub 1} and LPA{sub 3} enhanced MMP-2 activation in PANC-1 cells. • The expressions of LPAR1 and LPAR3 genes were elevated in PANC-1 cells treated with cisplatin. • The cell motile and invasive activities of PANC-1 cells treated with cisplatin were suppressed by LPA{sub 1} and LPA{sub 3} knockdown. • LPA{sub 1} and LPA{sub 3} are involved in the regulation of cellular functions during tumor progression in PANC-1 cells.« less

Sperm Mitochondrial Integrity Is Not Required for Hyperactivated Motility, Zona Binding, or Acrosome Reaction in the Rhesus Macaque1

PubMed Central

Hung, Pei-hsuan; Miller, Marion G.; Meyers, Stuart A.; VandeVoort, Catherine A.

2008-01-01

Whether the main energy source for sperm motility is from oxidative phosphorylation or glycolysis has been long-debated in the field of reproductive biology. Using the rhesus monkey as a model, we examined the role of glycolysis and oxidative phosphorylation in sperm function by using alpha-chlorohydrin (ACH), a glycolysis inhibitor, and pentachlorophenol (PCP), an oxidative phosphorylation uncoupler. Sperm treated with ACH showed no change in percentage of motile sperm, although sperm motion was impaired. The ACH-treated sperm did not display either hyperactivity- or hyperactivation-associated changes in protein tyrosine phosphorylation. When treated with PCP, sperm motion parameters were affected by the highest level of PCP (200 μM); however, PCP did not cause motility impairments even after chemical activation. Sperm treated with PCP were able to display hyperactivity and tyrosine phosphorylation after chemical activation. In contrast with motility measurements, treatment with either the glycolytic inhibitor or the oxidative phosphorylation inhibitor did not affect sperm-zona binding and zona-induced acrosome reaction. The results suggest glycolysis is essential to support sperm motility, hyperactivity, and protein tyrosine phosphorylation, while energy from oxidative phosphorylation is not necessary for hyperactivated sperm motility, tyrosine phosphorylation, sperm-zona binding, and acrosome reaction in the rhesus macaque. PMID:18480469

Dynactin functions as both a dynamic tether and brake during dynein-driven motility

NASA Astrophysics Data System (ADS)

Ayloo, Swathi; Lazarus, Jacob E.; Dodda, Aditya; Tokito, Mariko; Ostap, E. Michael; Holzbaur, Erika L. F.

2014-09-01

Dynactin is an essential cofactor for most cellular functions of the microtubule motor cytoplasmic dynein, but the mechanism by which dynactin activates dynein remains unclear. Here we use single molecule approaches to investigate dynein regulation by the dynactin subunit p150Glued. We investigate the formation and motility of a dynein-p150Glued co-complex using dual-colour total internal reflection fluorescence microscopy. p150Glued recruits and tethers dynein to the microtubule in a concentration-dependent manner. Single molecule imaging of motility in cell extracts demonstrates that the CAP-Gly domain of p150Glued decreases the detachment rate of the dynein-dynactin complex from the microtubule and also acts as a brake to slow the dynein motor. Consistent with this important role, two neurodegenerative disease-causing mutations in the CAP-Gly domain abrogate these functions in our assays. Together, these observations support a model in which dynactin enhances the initial recruitment of dynein onto microtubules and promotes the sustained engagement of dynein with its cytoskeletal track.

Downregulation of a mitochondria associated protein SLP-2 inhibits tumor cell motility, proliferation and enhances cell sensitivity to chemotherapeutic reagents.

PubMed

Wang, Yueqi; Cao, Wenfeng; Yu, Zaicheng; Liu, Zhihua

2009-09-01

Results from tissue microarray in this study and our previous reports revealed that stomatin-like protein 2 (SLP-2) is notably associated with tumorigenesis and metastasis. Many members of stomatin family are involved in tumor as mitochondrial component, and recent study has revealed that SLP-2 may also function in mitochondria. To further investigate the function of SLP-2, we used siRNA target SLP-2. Data showed that knock-down of SLP-2 potently inhibited cell motility, proliferation and slightly altered cell cycle without any significant change of apoptosis. Moreover, by combined application with different chemotherapeutic reagents, we observed the enhancement of cell chemosensitivity by SLP-2 depletion. We also confirmed that, SLP-2 localizes in mitochondria, affects mitochondrial membrane potential (MMP) and ATP production. We conclude that, SLP-2 is a mitochondrial protein and therefore, functions in energy process by MMP maintenance, and subsequently affecting cell motility, proliferation and chemosensitivity.

A new media without animal component for sperm cryopreservation: motility and various attributes affecting paternal contribution of sperm.

PubMed

Tiwari, Akansha; Tekcan, Merih; Sati, Leyla; Murk, William; Stronk, Jill; Huszar, Gabor

2017-05-01

Our aim was the development of a safe sperm cryopreservation New Media (NM), composed of consistent and reproducible components devoid of any animal origin, and evaluation of NM in terms of its effect on sperm structure and function as compared to regularly used yolk media (TYM) (Irvine Scientific). We evaluated patient semen samples and cryopreserved them in duplicates in either NM or TYM. The samples were cryopreserved for either a short term of 1 week or long term of 1 month prior to thawing. The parameters investigated include sperm motility via computer-assisted semen analysis (CASA), sperm concentration, and sperm biomarkers that promote paternal contribution of spermatozoa to fertilization including hyaluronic acid binding, chromatin maturity, apoptotic markers, cytoplasmic retention, and sperm DNA integrity. As compared to TYM, NM was equally capable of sperm cryopreservation with both short-term and long-term storage in media, and after freeze-thaw and gradient processing of sperm. HA binding of sperm was comparable post thaw in both NM and yolk media. There are also no differences observed between the samples cryopreserved in NM or TYM in terms of their aniline blue staining, CK immunocytochemistry, caspase 3 immunostaining, or DNA nick translation. NM has the advantage of being xeno-free, yet in preservation of sperm motility and other sperm attributes, the NM is as effective as the TYM.

A biopolymer transistor: electrical amplification by microtubules.

PubMed

Priel, Avner; Ramos, Arnolt J; Tuszynski, Jack A; Cantiello, Horacio F

2006-06-15

Microtubules (MTs) are important cytoskeletal structures engaged in a number of specific cellular activities, including vesicular traffic, cell cyto-architecture and motility, cell division, and information processing within neuronal processes. MTs have also been implicated in higher neuronal functions, including memory and the emergence of "consciousness". How MTs handle and process electrical information, however, is heretofore unknown. Here we show new electrodynamic properties of MTs. Isolated, taxol-stabilized MTs behave as biomolecular transistors capable of amplifying electrical information. Electrical amplification by MTs can lead to the enhancement of dynamic information, and processivity in neurons can be conceptualized as an "ionic-based" transistor, which may affect, among other known functions, neuronal computational capabilities.

Evaluation of esophageal function in patients with esophageal motor abnormalities using multichannel intraluminal impedance esophageal manometry.

PubMed

Cho, Yu Kyung; Choi, Myung-Gyu; Park, Jae Myung; Oh, Jung Hwan; Paik, Chang Nyol; Lee, Joon Wook; Lee, In Seok; Kim, Sang Woo; Chung, In-Sik

2006-10-21

To evaluate the functional aspect of esophageal motility in healthy subjects and in patients who were referred for esophageal function testing using multichannel intraluminal impedance-esophageal manometry (MII-EM), and to assess the clinical utility of MII-EM. From September 2003 to January 2004, we performed the MII-EM on healthy volunteers and all the patients who were referred for esophageal function testing. Each patient received 10 liquid and 10 viscous swallows. We analyzed the results, the impedance and the manometric findings. Some of the subjects had additional ambulatory 24-h pH study performed to diagnose gastroesophageal reflux disease (GERD). Among 89 studied subjects, the MII-EM findings showed normal esophageal motility in 50 (56.17%), ineffective esophageal motility (IEM) in 17 (19.10%), nutcracker esophagus in 7 (7.86%), achalasia in 4 (4.49%), and scleroderma esophagus in 11 (12.35%) cases. The completeness and the speed of bolus transit were in the order of nutcracker esophagus, normal manometry and IEM. Some of the swallows showing normal manometry and IEM had incomplete transit. In the achalasia and scleroderma esophagus, almost all the swallows had incomplete transit. The body amplitudes were higher for the swallows with complete transit than for the swallows with incomplete transit. There was not a significant difference in the manometric and impedance findings between the subjects with and without GERD. MII-EM is a useful tool in assessing the esophageal function in the patients having esophageal motility abnormality. The primary factors influencing the bolus transit are the amplitude of the esophageal body and normal peristalsis.

Cryopreservation of boar semen by egg yolk-based extenders containing lactose or fructose is better than sorbitol.

PubMed

Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

2012-03-01

The present study determined the effect of different types of sugars (lactose, fructose, glucose and sorbitol) used in egg yolk-based extender on the post-thawed boar semen quality. Twenty-two ejaculates from 6 fertility-proven Yorkshire boars were cryopreserved by liquid nitrogen vapor method. Sperm motility, viability, acrosome integrity and intact functional plasma membrane were determined at 0, 2 and 4 hr after thawing. It was found that the lactose-based extender resulted in a higher percentage of post-thawed sperm motility, viability, intact acrosome and functional plasma membrane than sorbitol-based extender (P<0.05) and fructose-based extender yielded a higher post-thawed sperm motility and viability than sorbitol-based extender (P<0.05). It could be concluded that sorbitol was not an effective sugar for the cryopreservation in boar semen.

Effects of acute postnatal exposure to 3,3',4,4'-tetrachlorobiphenyl on sperm function and hormone levels in adult rats.

PubMed

Hsu, Ping-Chi; Guo, Yueliang Leon; Li, Mei-Hui

2004-02-01

Polychlorinated biphenyls (PCBs) are considered potential endocrine disruptors due to their ability to act as estrogens, antiestrogens and goitrogens. The aim of this study is to ascertain whether acute postnatal treatment with 3,3',4,4'-tetrachlorobiphenyl (CB 77) affects sperm function and hormone levels in adult rats. Male Sprague-Dawley rats received CB 77 by ip injection of 2 or 20 mg/kg at day 21 and sacrificed at day 112. At day 112, right and left testis weights were significantly increased, whereas sperm count, motility, total motile sperm count, curvilinear velocity, average path velocity, straight-line velocity, and beat-cross frequency for motile sperm were significantly decreased in rats treated with 20 mg/kg CB 77. Sperm-oocyte penetration rate was significantly reduced in rats treated with either 2 or 20 mg/kg CB 77. There was high sperm acrosome reaction rate (ARR) in the 20 mg/kg CB 77-treated rats. There was a significant increase in thyroid-stimulating hormone level in the 20 mg/kg CB 77 group. However, no changes were seen in serum testosterone, thyroid hormones, or prolactin concentrations at day 112. In summary, this study showed that postnatal exposure to CB 77 might affect spermatogenesis, motility, ARR, and ability of fertilizing oocytes in mature rats. These results suggest that the sperm functions may be more susceptible or adapt less readily than the thyroid functions to endocrine disruption caused by dioxin-like PCB congeners.

Queue up, please! Spermathecal filling in the rove beetle Drusilla canaliculata (Coleoptera, Staphylinidae)

NASA Astrophysics Data System (ADS)

Werner, Michael; Gack, Claudia; Speck, Thomas; Peschke, Klaus

2007-10-01

Most studies on insect sperm motility have been conducted in vitro using artificial environments outside the animal’s body. Only little is known about the function of motile insect sperm at different sites within the male or female genital tracts. We dissected genital tracts of female rove beetles ( Drusilla canaliculata) to show that spermatozoa use their own motility to migrate from the spermatophore into the spermatheca. Our dissection method allowed direct observation and filming of the spermathecal filling process inside the female’s genital tract. Spermatozoa were found to enter the spermatheca individually, sometimes in groups of two or three. Although exhibiting only weak motility and no progressive motion in buffer solution, the spermatozoa inside the female show vigorous lashing and reach an average velocity of 47.5 μm s-1. To gain mobility and speed, the spermatozoa likely utilize the relatively small diameter of the spermathecal duct to push themselves off the duct walls, rather than swimming freely in seminal fluid. The spermatozoa (approximately 1,250 μm) are considerably longer than the distance they have to travel along the spermathecal duct (approximately 800 μm). Our study provides the first direct observation of active sperm migration within the female of an insect stressing the importance of the genital tract as a prerequisite for functional sperm motility.

A putative regulatory genetic locus modulates virulence in the pathogen Leptospira interrogans.

PubMed

Eshghi, Azad; Becam, Jérôme; Lambert, Ambroise; Sismeiro, Odile; Dillies, Marie-Agnès; Jagla, Bernd; Wunder, Elsio A; Ko, Albert I; Coppee, Jean-Yves; Goarant, Cyrille; Picardeau, Mathieu

2014-06-01

Limited research has been conducted on the role of transcriptional regulators in relation to virulence in Leptospira interrogans, the etiological agent of leptospirosis. Here, we identify an L. interrogans locus that encodes a sensor protein, an anti-sigma factor antagonist, and two genes encoding proteins of unknown function. Transposon insertion into the gene encoding the sensor protein led to dampened transcription of the other 3 genes in this locus. This lb139 insertion mutant (the lb139(-) mutant) displayed attenuated virulence in the hamster model of infection and reduced motility in vitro. Whole-transcriptome analyses using RNA sequencing revealed the downregulation of 115 genes and the upregulation of 28 genes, with an overrepresentation of gene products functioning in motility and signal transduction and numerous gene products with unknown functions, predicted to be localized to the extracellular space. Another significant finding encompassed suppressed expression of the majority of the genes previously demonstrated to be upregulated at physiological osmolarity, including the sphingomyelinase C precursor Sph2 and LigB. We provide insight into a possible requirement for transcriptional regulation as it relates to leptospiral virulence and suggest various biological processes that are affected due to the loss of native expression of this genetic locus.

Sperm preparation for ART

PubMed Central

Henkel, Ralf R; Schill, Wolf-Bernhard

2003-01-01

The onset of clinical assisted reproduction, a quarter of a century ago, required the isolation of motile spermatozoa. As the indication of assisted reproduction shifted from mere gynaecological indications to andrological indications during the years, this urged andrological research to understand the physiology of male germ cell better and develop more sophisticated techniques to separate functional spermatozoa from those that are immotile, have poor morphology or are not capable to fertilize oocytes. Initially, starting from simple washing of spermatozoa, separation techniques, based on different principles like migration, filtration or density gradient centrifugation evolved. The most simple and cheapest is the conventional swim-up procedure. A more sophisticated and most gentle migration method is migration-sedimentation. However, its yield is relatively small and the technique is therefore normally only limited to ejaculates with a high number of motile spermatozoa. Recently, however, the method was also successfully used to isolate spermatozoa for intracytoplasmic sperm injection (ICSI). Sperm separation methods that yield a higher number of motile spermatozoa are glass wool filtration or density gradient centrifugation with different media. Since Percoll® as a density medium was removed from the market in 1996 for clinical use in the human because of its risk of contamination with endotoxins, other media like IxaPrep®, Nycodenz, SilSelect®, PureSperm® or Isolate® were developed in order to replace Percoll®. Today, an array of different methods is available and the selection depends on the quality of the ejaculates, which also includes production of reactive oxygen species (ROS) by spermatozoa and leukocytes. Ejaculates with ROS production should not be separated by means of conventional swim-up, as this can severely damage the spermatozoa. In order to protect the male germ cells from the influence of ROS and to stimulate their motility to increase the yield, a number of substances can be added to the ejaculate or the separation medium. Caffeine, pentoxifylline and 2-deoxyadenosine are substances that were used to stimulate motility. Recent approaches to stimulate spermatozoa include bicarbonate, metal chelators or platelet-activating factor (PAF). While the use of PAF already resulted in pregnancies in intrauterine insemination, the suitability of the other substances for the clinical use still needs to be tested. Finally, the isolation of functional spermatozoa from highly viscous ejaculates is a special challenge and can be performed enzymatically to liquefy the ejaculate. The older method, by which the ejaculate is forcefully aspirated through a narrow-gauge needle, should be abandoned as it can severely damage spermatozoa, thus resulting in immotile sperm. PMID:14617368

HIV-1 Nef interferes with host cell motility by deregulation of Cofilin.

PubMed

Stolp, Bettina; Reichman-Fried, Michal; Abraham, Libin; Pan, Xiaoyu; Giese, Simone I; Hannemann, Sebastian; Goulimari, Polyxeni; Raz, Erez; Grosse, Robert; Fackler, Oliver T

2009-08-20

HIV-1 Nef is a key factor in AIDS pathogenesis. Here, we report that Nef potently inhibits motility of fibroblasts and chemotaxis of HIV-1-infected primary human T lymphocytes toward the chemokines SDF-1alpha, CCL-19, and CCL-21 ex vivo. Furthermore, Nef inhibits guided motility of zebrafish primordial germ cells toward endogenous SDF-1a in vivo. These migration defects result from Nef-mediated inhibition of the actin remodeling normally triggered by migratory stimuli. Nef strongly induces phosphorylation of cofilin, inactivating this evolutionarily conserved actin-depolymerizing factor that promotes cell motility when unphosphorylated. Nef-dependent cofilin deregulation requires association of Nef with the cellular kinase Pak2. Disruption of Nef-Pak2 association restores the cofilin phosphorylation levels and actin remodeling that facilitate cell motility. We conclude that HIV-1 Nef alters Pak2 function, which directly or indirectly inactivates cofilin, thereby restricting migration of infected T lymphocytes as part of a strategy to optimize immune evasion and HIV-1 replication.

A Microbial Drugstore for Motility.

PubMed

Cryan, John F; Clarke, Gerard; Dinan, Timothy G; Schellekens, Harriet

2018-06-13

While there is growing appreciation that the microbiome regulates gut-brain signaling, the underlying mechanisms remain elusive. In this issue of Cell Host & Microbe, Bhattarai et al. (2018) identify bacteria-derived tryptamine as a ligand for the gut-epithelium-expressed GPCR 5-HT4 receptor, thereby functioning as a regulator of gastrointestinal motility. Copyright © 2018 Elsevier Inc. All rights reserved.

Do Uric Acid Deposits in Zooxanthellae Function as Eye-Spots?

PubMed Central

Yamashita, Hiroshi; Kobiyama, Atsushi; Koike, Kazuhiko

2009-01-01

The symbiosis between zooxanthellae (dinoflagellate genus Symbiodinium) and corals is a fundamental basis of tropical marine ecosystems. However the physiological interactions of the hosts and symbionts are poorly understood. Recently, intracellular crystalline deposits in Symbiodinium were revealed to be uric acid functioning for nutrient storage. This is the first exploration of these enigmatic crystalline materials that had previously been misidentified as oxalic acid, providing new insights into the nutritional strategies of Symbiodinium in oligotrophic tropical waters. However, we believe these deposits also function as eye-spots on the basis of light and electron microscopic observations of motile cells of cultured Symbiodinium. The cells possessed crystalline deposit clusters in rows with each row 100–150 nm thick corresponding to 1/4 the wavelength of light and making them suitable for maximum wave interference and reflection of light. Crystalline clusters in cells observed with a light microscope strongly refracted and polarized light, and reflected or absorbed short wavelength light. The facts that purines, including uric acid, have been identified as the main constituents of light reflectors in many organisms, and that the photoreceptor protein, opsin, was detected in our Symbiodinium strain, support the idea that uric acid deposits in Symbiodinium motile cells may function as a component of an eye-spot. PMID:19609449

Do uric acid deposits in zooxanthellae function as eye-spots?

PubMed

Yamashita, Hiroshi; Kobiyama, Atsushi; Koike, Kazuhiko

2009-07-17

The symbiosis between zooxanthellae (dinoflagellate genus Symbiodinium) and corals is a fundamental basis of tropical marine ecosystems. However the physiological interactions of the hosts and symbionts are poorly understood. Recently, intracellular crystalline deposits in Symbiodinium were revealed to be uric acid functioning for nutrient storage. This is the first exploration of these enigmatic crystalline materials that had previously been misidentified as oxalic acid, providing new insights into the nutritional strategies of Symbiodinium in oligotrophic tropical waters. However, we believe these deposits also function as eye-spots on the basis of light and electron microscopic observations of motile cells of cultured Symbiodinium. The cells possessed crystalline deposit clusters in rows with each row 100-150 nm thick corresponding to 1/4 the wavelength of light and making them suitable for maximum wave interference and reflection of light. Crystalline clusters in cells observed with a light microscope strongly refracted and polarized light, and reflected or absorbed short wavelength light. The facts that purines, including uric acid, have been identified as the main constituents of light reflectors in many organisms, and that the photoreceptor protein, opsin, was detected in our Symbiodinium strain, support the idea that uric acid deposits in Symbiodinium motile cells may function as a component of an eye-spot.

Membrane tension and cytoskeleton organization in cell motility.

PubMed

Sens, Pierre; Plastino, Julie

2015-07-15

Cell membrane shape changes are important for many aspects of normal biological function, such as tissue development, wound healing and cell division and motility. Various disease states are associated with deregulation of how cells move and change shape, including notably tumor initiation and cancer cell metastasis. Cell motility is powered, in large part, by the controlled assembly and disassembly of the actin cytoskeleton. Much of this dynamic happens in close proximity to the plasma membrane due to the fact that actin assembly factors are membrane-bound, and thus actin filaments are generally oriented such that their growth occurs against or near the membrane. For a long time, the membrane was viewed as a relatively passive scaffold for signaling. However, results from the last five years show that this is not the whole picture, and that the dynamics of the actin cytoskeleton are intimately linked to the mechanics of the cell membrane. In this review, we summarize recent findings concerning the role of plasma membrane mechanics in cell cytoskeleton dynamics and architecture, showing that the cell membrane is not just an envelope or a barrier for actin assembly, but is a master regulator controlling cytoskeleton dynamics and cell polarity.

The Rcs regulon in Proteus mirabilis: implications for motility, biofilm formation, and virulence.

PubMed

Howery, Kristen E; Clemmer, Katy M; Rather, Philip N

2016-11-01

The overall role of the Rcs phosphorelay in Proteus mirabilis is largely unknown. Previous work had demonstrated that the Rcs phosphorelay represses the flhDC operon and activates the minCDE cell division inhibition system. To identify additional cellular functions regulated by the Rcs phosphorelay, an analysis of RNA-seq data was undertaken. In this report, the results of the RNA-sequencing are discussed with an emphasis on the predicted roles of the Rcs phosphorelay in swarmer cell differentiation, motility, biofilm formation, and virulence. RcsB is shown to activate genes important for differentiation and fimbriae formation, while repressing the expression of genes important for motility and virulence. Additionally, to follow up on the RNA-Seq data, we demonstrate that an rcsB mutant is deficient in its ability to form biofilm and exhibits enhanced virulence in a Galleria mellonella waxworm model. Overall, these results indicate the Rcs regulon in P. mirabilis extends beyond flagellar genes to include those involved in biofilm formation and virulence. Furthermore, the information presented in this study may provide clues to additional roles of the Rcs phosphorelay in other members of the Enterobacteriaceae.

Esophageal motility pattern and gastro-esophageal reflux in chronic obstructive pulmonary disease.

PubMed

Gadel, Abil Ali; Mostafa, Mohamed; Younis, Ahmed; Haleem, Magdy

2012-01-01

The association of esophageal motility and gastroesophageal reflux symptoms with respiratory symptoms is not well established in patients with chronic obstructive pulmonary disease (COPD). The aim of this work is to study the abnormalities of esophageal function in COPD patients and study its relation to smoking index, body mass index and indices of hyperinflation. This study included 40 male COPD patients and 10 healthy controls. The patients and controls were subjected to spirometry, body plethysmography, esophageal manometry and 24hr pH-metry. Upper gastrointestinal symptoms were found in 55% of patients, hypotensive upper esophageal sphincter pressure in 65% of patients and hypotensive lower esophageal sphincter pressure in 52.5% of patients. Pathological acid reflux was found in 35% of patients. The severity of GERD increased with increased age, smoking index and body mass index, p<0.005. There was negative correlation between LESP and UESP compared with indices of hyperinflation, p<0.001. There was high prevalence of esophageal motility disorders in COPD patients, LESP and UESP were significantly negatively correlated to indices of hyperinflation. There was a high prevalence of GERD in COPD patents especially elderly, severe stage of COPD, high smoking index and high body mass index (BMI).

Biophysical Properties and Motility of Human Mature Dendritic Cells Deteriorated by Vascular Endothelial Growth Factor through Cytoskeleton Remodeling

PubMed Central

Hu, Zu-Quan; Xue, Hui; Long, Jin-Hua; Wang, Yun; Jia, Yi; Qiu, Wei; Zhou, Jing; Wen, Zong-Yao; Yao, Wei-Juan; Zeng, Zhu

2016-01-01

Dendritic cells (DCs), the most potent antigen-presenting cells, play a central role in the initiation, regulation, and maintenance of the immune responses. Vascular endothelial growth factor (VEGF) is one of the important cytokines in the tumor microenvironment (TME) and can inhibit the differentiation and functional maturation of DCs. To elucidate the potential mechanisms of DC dysfunction induced by VEGF, the effects of VEGF on the biophysical characteristics and motility of human mature DCs (mDCs) were investigated. The results showed that VEGF had a negative influence on the biophysical properties, including electrophoretic mobility, osmotic fragility, viscoelasticity, and transmigration. Further cytoskeleton structure analysis by confocal microscope and gene expression profile analyses by gene microarray and real-time PCR indicated that the abnormal remodeling of F-actin cytoskeleton may be the main reason for the deterioration of biophysical properties, motility, and stimulatory capability of VEGF-treated mDCs. This is significant for understanding the biological behavior of DCs and the immune escape mechanism of tumors. Simultaneously, the therapeutic efficacies may be improved by blocking the signaling pathway of VEGF in an appropriate manner before the deployment of DC-based vaccinations against tumors. PMID:27809226

Functional Analysis of the Chaperone-Usher Fimbrial Gene Clusters of Salmonella enterica serovar Typhi.

PubMed

Dufresne, Karine; Saulnier-Bellemare, Julie; Daigle, France

2018-01-01

The human-specific pathogen Salmonella enterica serovar Typhi causes typhoid, a major public health issue in developing countries. Several aspects of its pathogenesis are still poorly understood. S . Typhi possesses 14 fimbrial gene clusters including 12 chaperone-usher fimbriae ( stg, sth, bcf , fim, saf , sef , sta, stb, stc, std, ste , and tcf ). These fimbriae are weakly expressed in laboratory conditions and only a few are actually characterized. In this study, expression of all S . Typhi chaperone-usher fimbriae and their potential roles in pathogenesis such as interaction with host cells, motility, or biofilm formation were assessed. All S . Typhi fimbriae were better expressed in minimal broth. Each system was overexpressed and only the fimbrial gene clusters without pseudogenes demonstrated a putative major subunits of about 17 kDa on SDS-PAGE. Six of these (Fim, Saf, Sta, Stb, Std, and Tcf) also show extracellular structure by electron microscopy. The impact of fimbrial deletion in a wild-type strain or addition of each individual fimbrial system to an S . Typhi afimbrial strain were tested for interactions with host cells, biofilm formation and motility. Several fimbriae modified bacterial interactions with human cells (THP-1 and INT-407) and biofilm formation. However, only Fim fimbriae had a deleterious effect on motility when overexpressed. Overall, chaperone-usher fimbriae seem to be an important part of the balance between the different steps (motility, adhesion, host invasion and persistence) of S . Typhi pathogenesis.

The influence of macro- and microelements in seminal plasma on diluted boar sperm quality.

PubMed

Pipan, Maja Zakošek; Mrkun, Janko; Strajn, Breda Jakovac; Vrtač, Katarina Pavšič; Kos, Janko; Pišlar, Anja; Zrimšek, Petra

2017-02-10

Growing evidence indicates that macro- and microelements in the seminal plasma of humans and various domestic animals are of great importance due to their roles in sperm metabolism, function, survival and oxidative stress. In the present study, we therefore determined the concentrations of macro- and microelements in fresh boar seminal plasma and their relation to sperm quality parameters after 3 days of liquid storage was assessed. Twenty ejaculates from eight boars were collected, and semen volume, concentration, sperm motility, morphology, tail membrane integrity, plasma membrane permeability, mitochondrial membrane potential and DNA fragmentation were determined on the day of collection (day 0) and day 3 (72 h) of storage at 15-17 °C. Seminal plasma was separated and the concentrations of macroelements (Na, K, Ca, and Mg) and microelements (Cu, Fe, Zn and Se) were determined. After 3 days of storage Se levels correlated significantly with sperm motility, progressive motility and morphology, all of which are routinely used for semen evaluation. On day 3, Se levels also correlated with tail membrane integrity, viability and intact DNA (P < 0.05). The correlation coefficients showed that mitochondrial function was better preserved at higher levels of Zn, while higher levels of Cu decreased mitochondrial function, but led to the better preservation of DNA. It was also evident that higher levels of Fe were associated with higher proportions of live spermatozoa and of spermatozoa with normal morphology after 3 days of storage (P < 0.05), while higher levels of Ca and Mg in fresh seminal plasma were associated with lower percentages of progressive motile spermatozoa and with a decreased proportion of spermatozoa with intact DNA (P < 0.05). Multivariate analysis including microelements showed that Se significantly affected sperm quality parameters, mentioned above, after 3 days of storage. Macro- and microelements were associated with boar sperm quality and may be important biomarkers of boar sperm quality after liquid storage. Our results demonstrate that the evaluation of Se in fresh boar seminal plasma can serve as an additional tool in predicting sperm quality after storage.

PillCam(TradeMark), a Noninvasive Endoscopic Device for the Measurement of Gastrointestinal Motility Changes

NASA Technical Reports Server (NTRS)

Vaksman, Zahman; Crady, Camille; Raju, G. S.; Putcha, Lakshmi

2007-01-01

Introduction: Bioavailability and effectiveness of drugs given by mouth are governed in part by gastrointestinal (GI) motility and function. Microgravity has been shown to decrease GI motility as indicated by a 3 fold increase in gastrointestinal transit time (GITT). The PillCam(TradeMark), an endoscopic camera embedded in a capsule, is a novel noninvasive and unobtrusive device that is used for the diagnosis of GI pathology. The purpose of this study is to evaluate the usefulness of PillCam(TradeMark) as an alternative to the Lactulose Breath Hydrogen Test (LBHT) for estimating GI motility. The sensitivity and applicability of this device for detection and estimation of the effect of promethazine, a deterrent, and caffeine, a prokinetic, on GI motility were also examined. Method: In this semi-randomized cross-over design study, six male and six female subjects were administered the following 4 treatments: PillCam(TradeMark) alone, PillCam(TradeMark)+Lactulose (10g), PillCam(TradeMark)+caffeine (200mg), and PillCam(TradeMark)+Promethazine (50mg). Results: GITT ranged between 1:24 and 7:52 hr:min. Lactulose did not alter GITT. A significant increase in GITT was noticed after administration of PMZ when compared to values from PillCam(TradeMark) treatment alone or PillCam(TradeMark)+Lactulose treatment. No difference in GITT after caffeine treatment was noticed. While there were no gender related differences in GITT after administration of PillCam(TradeMark) or with lactulose, a significant difference (p<.05) between genders was observed after promethazine administration with mean GITT higher in males (5:50 hr:min) than females (4:15 hr:min). Conclusion: The PillCam(TradeMark) capsule is applicable for the determination of GITT using time stamped GI images. It can be successfully used for the assessment of drug induced changes in GI motility and therefore, may be applicable for microgravity and analog environment studies on GI motility and function.

Assessment of azadirachtin-A, a neem tetranortritarpinoid, on rat spermatozoa during in vitro capacitation.

PubMed

Katte, Teesta V; Rajyalakshmi, Malempati; Aladakatti, Ravindranath H

2018-05-05

The exploration of the biological assessment of technical azadirachtin, a tetranortritarpinoid from the neem seed kernel, was reviewed. The present study was, therefore, designed to evaluate the dose-dependent in vitro effects of azadirachtin-A, particularly on the functional studies and determination of molecular events, which are critical in the process of sperm capacitation. To assess the effects of the azadirachtin-A on the functional studies, sperm capacitation, the total sperm adenosine triphosphate levels, acrosome reaction (AR), the sperm-egg interaction and the determination of molecular events like cyclic adenosine-3',5'-monophosphate and calcium levels, the appropriate volumes of the sperm suspension were added to the medium to a final concentration of 1×106 sperm/mL and incubated in a humidified atmosphere of 5% CO2 in air at 37°C. The increasing quantities 0.5-2.0 mM/mL and the equivalent volumes of 50% dimethyl sulfoxide were added to the control dishes prior to the addition of spermatozoa and then observed at various time-points for motility and other analyses. Results revealed the dose- and time-dependent decrease in the functional consequence of capacitation, i.e. the percentage of motile spermatozoa, motility score and sperm motility index, levels of molecular events in spermatozoa, followed by declined spontaneous AR leading to lesser binding of the cauda epididymal sperm to the Zona pellucida. The findings confirm the inhibition of rat sperm motility by blocking some biochemical pathways like energy utilization. They also demonstrate that sperm capacitation is associated with the decrease in AR and that the levels of molecular events in spermatozoa can guide us towards the development of a new male contraceptive constituent.

An in silico agent-based model demonstrates Reelin function in directing lamination of neurons during cortical development.

PubMed

Caffrey, James R; Hughes, Barry D; Britto, Joanne M; Landman, Kerry A

2014-01-01

The characteristic six-layered appearance of the neocortex arises from the correct positioning of pyramidal neurons during development and alterations in this process can cause intellectual disabilities and developmental delay. Malformations in cortical development arise when neurons either fail to migrate properly from the germinal zones or fail to cease migration in the correct laminar position within the cortical plate. The Reelin signalling pathway is vital for correct neuronal positioning as loss of Reelin leads to a partially inverted cortex. The precise biological function of Reelin remains controversial and debate surrounds its role as a chemoattractant or stop signal for migrating neurons. To investigate this further we developed an in silico agent-based model of cortical layer formation. Using this model we tested four biologically plausible hypotheses for neuron motility and four biologically plausible hypotheses for the loss of neuron motility (conversion from migration). A matrix of 16 combinations of motility and conversion rules was applied against the known structure of mouse cortical layers in the wild-type cortex, the Reelin-null mutant, the Dab1-null mutant and a conditional Dab1 mutant. Using this approach, many combinations of motility and conversion mechanisms can be rejected. For example, the model does not support Reelin acting as a repelling or as a stopping signal. In contrast, the study lends very strong support to the notion that the glycoprotein Reelin acts as a chemoattractant for neurons. Furthermore, the most viable proposition for the conversion mechanism is one in which conversion is affected by a motile neuron sensing in the near vicinity neurons that have already converted. Therefore, this model helps elucidate the function of Reelin during neuronal migration and cortical development.

Axonal transport: cargo-specific mechanisms of motility and regulation.

PubMed

Maday, Sandra; Twelvetrees, Alison E; Moughamian, Armen J; Holzbaur, Erika L F

2014-10-22

Axonal transport is essential for neuronal function, and many neurodevelopmental and neurodegenerative diseases result from mutations in the axonal transport machinery. Anterograde transport supplies distal axons with newly synthesized proteins and lipids, including synaptic components required to maintain presynaptic activity. Retrograde transport is required to maintain homeostasis by removing aging proteins and organelles from the distal axon for degradation and recycling of components. Retrograde axonal transport also plays a major role in neurotrophic and injury response signaling. This review provides an overview of axonal transport pathways and discusses their role in neuronal function.

A Role for the Chemokine Receptor CCR6 in Mammalian Sperm Motility and Chemotaxis

PubMed Central

Caballero-Campo, Pedro; Buffone, Mariano G.; Benencia, Fabian; Conejo-García, José R.; Rinaudo, Paolo F.; Gerton, George L.

2013-01-01

Although recent evidence indicates that several chemokines and defensins, well-known as inflammatory mediators, are expressed in the male and female reproductive tracts, the location and functional significance of chemokine networks in sperm physiology and sperm reproductive tract interactions are poorly understood. To address this deficiency in our knowledge, we examined the expression and function in sperm of CCR6, a receptor common to several chemoattractant peptides, and screened several reproductive tract fluids for the presence of specific ligands. CCR6 protein is present in mouse and human sperm and mainly localized in the sperm tail with other minor patterns in sperm from mice (neck and acrosomal region) and men (neck and midpiece regions). As expected from the protein immunoblotting and immunofluorescence results, mouse Ccr6 mRNA is expressed in the testis. Furthermore, the Defb29 mRNA encoding the CCR6 ligand, β-defensin DEFB29, is expressed at high levels in the epididymis. As determined by protein chip analysis, several chemokines (including some that act through CCR6, such as CCL20/MIP-3α (formerly Macrophage Inflammatory Protein 3α) and protein hormones were present in human follicular fluid, endometrial secretions, and seminal plasma. In functional chemotaxis assays, capacitated human sperm exhibited a directional movement towards CCL20, and displayed modifications in motility parameters. Our data indicate that chemokine ligand/receptor interactions in the male and female genital tracts promote sperm motility and chemotaxis under non-inflammatory conditions. Therefore, some of the physiological reactions mediated by CCR6 ligands in male reproduction extend beyond a pro-inflammatory response and might find application in clinical reproduction and/or contraception. PMID:23765988

How does calcium interact with the cytoskeleton to regulate growth cone motility during axon pathfinding?

PubMed

Gasperini, Robert J; Pavez, Macarena; Thompson, Adrian C; Mitchell, Camilla B; Hardy, Holly; Young, Kaylene M; Chilton, John K; Foa, Lisa

2017-10-01

The precision with which neurons form connections is crucial for the normal development and function of the nervous system. The development of neuronal circuitry in the nervous system is accomplished by axon pathfinding: a process where growth cones guide axons through the embryonic environment to connect with their appropriate synaptic partners to form functional circuits. Despite intense efforts over many years to understand how this process is regulated, the complete repertoire of molecular mechanisms that govern the growth cone cytoskeleton and hence motility, remain unresolved. A central tenet in the axon guidance field is that calcium signals regulate growth cone behaviours such as extension, turning and pausing by regulating rearrangements of the growth cone cytoskeleton. Here, we provide evidence that not only the amplitude of a calcium signal is critical for growth cone motility but also the source of calcium mobilisation. We provide an example of this idea by demonstrating that manipulation of calcium signalling via L-type voltage gated calcium channels can perturb sensory neuron motility towards a source of netrin-1. Understanding how calcium signals can be transduced to initiate cytoskeletal changes represents a significant gap in our current knowledge of the mechanisms that govern axon guidance, and consequently the formation of functional neural circuits in the developing nervous system. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Rac2 Functions in Both Neutrophils and Macrophages To Mediate Motility and Host Defense in Larval Zebrafish.

PubMed

Rosowski, Emily E; Deng, Qing; Keller, Nancy P; Huttenlocher, Anna

2016-12-15

Leukocyte motility is required for host defense responses. Rac-family Rho GTPases are implicated in leukocyte function; however, the distinct roles of different Rac isoforms in host defense in vivo have remained unclear. In this study, we generated Rac2-deficient zebrafish using transcription activator-like effector nucleases to directly compare the role of Rac2 in vivo in neutrophils and macrophages in motility and the response to infection. This zebrafish larval model is highly amenable to live imaging of leukocyte behavior, and we report that in rac2 -/- larvae both neutrophils and macrophages are defective in basic motility, leading to impaired responses to localized wounds or infections. rac2 -/- larvae are highly susceptible to infection with Pseudomonas aeruginosa, which can be almost fully rescued by ectopic expression of either Rac2 or Rac1 specifically in neutrophils, indicating that these isoforms have partially overlapping functions in vivo. Rescue of Rac2 expression specifically in macrophages also confers resistance to Pseudomonas infection, highlighting an important role for Rac2 in this leukocyte population as well. Surprisingly, in contrast to neutrophils expressing a Rac2 dominant inhibitory human disease mutation, rac2 -/- neutrophils do not have altered polarity or mobilization from hematopoietic tissue, suggesting that a different Rac isoform, such as Rac1, also contributes to these phenotypes in vivo. Copyright © 2016 by The American Association of Immunologists, Inc.

Fibroblast Growth Factor Receptors (FGFRs) in Human Sperm: Expression, Functionality and Involvement in Motility Regulation.

PubMed

Saucedo, Lucía; Buffa, Gabriela N; Rosso, Marina; Guillardoy, Tomás; Góngora, Adrian; Munuce, María J; Vazquez-Levin, Mónica H; Marín-Briggiler, Clara

2015-01-01

Fibroblast growth factors receptors (FGFRs) have been widely characterized in somatic cells, but there is scarce evidence of their expression and function in mammalian gametes. The objective of the present study was to evaluate the expression of FGFRs in human male germ cells, to determine sperm FGFR activation by the FGF2 ligand and their participation in the regulation of sperm motility. The expression of FGFR1, 2, 3 and 4 mRNAs and proteins in human testis and localization of these receptors in germ cells of the seminiferous epithelium was demonstrated. In ejaculated sperm, FGFRs were localized to the acrosomal region and flagellum. Sperm exposure to FGF2 caused an increase in flagellar FGFR phosphorylation and activation of extracellular signal-regulated kinase (ERK) and protein kinase B (PKB or Akt) signaling pathways. Incubation with FGF2 led to a significant increase in the percentage of total and progressive sperm motility, as well as in sperm kinematics. All responses were prevented by sperm preincubation with BGJ398, a specific inhibitor of FGFR tyrosine kinase activity. In addition to confirming the expression of FGFRs in germ cells of the human testis, our study describes for the first time the presence, localization and functionality of human sperm FGFRs, and provides evidence of the beneficial effect of FGF2 upon sperm motility.

Fibroblast Growth Factor Receptors (FGFRs) in Human Sperm: Expression, Functionality and Involvement in Motility Regulation

PubMed Central

Saucedo, Lucía; Buffa, Gabriela N.; Rosso, Marina; Guillardoy, Tomás; Góngora, Adrian; Munuce, María J.

2015-01-01

Fibroblast growth factors receptors (FGFRs) have been widely characterized in somatic cells, but there is scarce evidence of their expression and function in mammalian gametes. The objective of the present study was to evaluate the expression of FGFRs in human male germ cells, to determine sperm FGFR activation by the FGF2 ligand and their participation in the regulation of sperm motility. The expression of FGFR1, 2, 3 and 4 mRNAs and proteins in human testis and localization of these receptors in germ cells of the seminiferous epithelium was demonstrated. In ejaculated sperm, FGFRs were localized to the acrosomal region and flagellum. Sperm exposure to FGF2 caused an increase in flagellar FGFR phosphorylation and activation of extracellular signal-regulated kinase (ERK) and protein kinase B (PKB or Akt) signaling pathways. Incubation with FGF2 led to a significant increase in the percentage of total and progressive sperm motility, as well as in sperm kinematics. All responses were prevented by sperm preincubation with BGJ398, a specific inhibitor of FGFR tyrosine kinase activity. In addition to confirming the expression of FGFRs in germ cells of the human testis, our study describes for the first time the presence, localization and functionality of human sperm FGFRs, and provides evidence of the beneficial effect of FGF2 upon sperm motility. PMID:25970615

Bidirectional motility of kinesin-5 motor proteins: structural determinants, cumulative functions and physiological roles.

PubMed

Singh, Sudhir Kumar; Pandey, Himanshu; Al-Bassam, Jawdat; Gheber, Larisa

2018-05-01

Mitotic kinesin-5 bipolar motor proteins perform essential functions in mitotic spindle dynamics by crosslinking and sliding antiparallel microtubules (MTs) apart within the mitotic spindle. Two recent studies have indicated that single molecules of Cin8, the Saccharomyces cerevisiae kinesin-5 homolog, are minus end-directed when moving on single MTs, yet switch directionality under certain experimental conditions (Gerson-Gurwitz et al., EMBO J 30:4942-4954, 2011; Roostalu et al., Science 332:94-99, 2011). This finding was unexpected since the Cin8 catalytic motor domain is located at the N-terminus of the protein, and such kinesins have been previously thought to be exclusively plus end-directed. In addition, the essential intracellular functions of kinesin-5 motors in separating spindle poles during mitosis can only be accomplished by plus end-directed motility during antiparallel sliding of the spindle MTs. Thus, the mechanism and possible physiological role of the minus end-directed motility of kinesin-5 motors remain unclear. Experimental and theoretical studies from several laboratories in recent years have identified additional kinesin-5 motors that are bidirectional, revealed structural determinants that regulate directionality, examined the possible mechanisms involved and have proposed physiological roles for the minus end-directed motility of kinesin-5 motors. Here, we summarize our current understanding of the remarkable ability of certain kinesin-5 motors to switch directionality when moving along MTs.

Tyrosine phosphorylation of dihydrolipoamide dehydrogenase as a potential cadmium target and its inhibitory role in regulating mouse sperm motility.

PubMed

Li, Xinhong; Wang, Lirui; Li, Yuhua; Fu, Jieli; Zhen, Linqing; Yang, Qiangzhen; Li, Sisi; Zhang, Yukun

2016-05-16

Cadmium (Cd) is reported to reduce sperm motility and functions. However, the molecular mechanisms of Cd-induced toxicity remain largely unknown, presenting a major knowledge gap in research on reproductive toxicology. In the present study, we identified a candidate protein, dihydrolipoamide dehydrogenase (DLD), which is a post-pyruvate metabolic enzyme, exhibiting tyrosine phosphorylation in mouse sperm exposed to Cd both in vivo and in vitro. Immunoprecipitation assay demonstrated DLD was phosphorylated in tyrosine residues without altered expression after Cd treatment, which further confirmed our identified result. However, the tyrosine phosphorylation of DLD did not participate in mouse sperm capacitation and Bovine Serum Albumin (BSA) effectively prevented the tyrosine phosphorylation of DLD. Moreover, Cd-induced tyrosine phosphorylation of DLD lowered its dehydrogenase activity and meanwhile, Nicotinamide Adenine Dinucleotide Hydrogen (NADH) content, Adenosine Triphosphate (ATP) production and sperm motility were all inhibited by Cd. Interestingly, when the tyrosine phosphorylation of DLD was blocked by BSA, the decrease of DLD activity, NADH and ATP content as well as sperm motility was also suppressed simultaneously. These results suggested that Cd-induced tyrosine phosphorylation of DLD inhibited its activity and thus suppressed the tricarboxylic acid (TCA) cycle, which resulted in the reduction of NADH and hence the ATP production generated through oxidative phosphorylation (OPHOXS). Taken together, our results revealed that Cd induced DLD tyrosine phosphorylation, in response to regulate TCA metabolic pathway, which reduced ATP levels and these negative effects led to decreased sperm motility. This study provided new understanding of the mechanisms contributing to the harmful effects of Cd on the motility and function of spermatozoa. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Agonists for G-protein-coupled receptor 84 (GPR84) alter cellular morphology and motility but do not induce pro-inflammatory responses in microglia.

PubMed

Wei, Li; Tokizane, Kyohei; Konishi, Hiroyuki; Yu, Hua-Rong; Kiyama, Hiroshi

2017-10-03

Several G-protein-coupled receptors (GPCRs) have been shown to be important signaling mediators between neurons and glia. In our previous screening for identification of nerve injury-associated GPCRs, G-protein-coupled receptor 84 (GPR84) mRNA showed the highest up-regulation by microglia after nerve injury. GPR84 is a pro-inflammatory receptor of macrophages in a neuropathic pain mouse model, yet its function in resident microglia in the central nervous system is poorly understood. We used endogenous, natural, and surrogate agonists for GPR84 (capric acid, embelin, and 6-OAU, respectively) and examined their effect on mouse primary cultured microglia in vitro. 6-n-Octylaminouracil (6-OAU), embelin, and capric acid rapidly induced membrane ruffling and motility in cultured microglia obtained from C57BL/6 mice, although these agonists failed to promote microglial pro-inflammatory cytokine expression. Concomitantly, 6-OAU suppressed forskolin-induced increase of cAMP in cultured microglia. Pertussis toxin, an inhibitor of Gi-coupled signaling, completely suppressed 6-OAU-induced microglial membrane ruffling and motility. In contrast, no 6-OAU-induced microglial membrane ruffling and motility was observed in microglia from DBA/2 mice, a mouse strain that does not express functional GPR84 protein due to endogenous nonsense mutation of the GPR84 gene. GPR84 mediated signaling causes microglial motility and membrane ruffling but does not promote pro-inflammatory responses. As GPR84 is a known receptor for medium-chain fatty acids, those released from damaged brain cells may be involved in the enhancement of microglial motility through GPR84 after neuronal injury.

Acotiamide hydrochloride (Z-338) enhances gastric motility and emptying by inhibiting acetylcholinesterase activity in rats.

PubMed

Kawachi, Masanao; Matsunaga, Yugo; Tanaka, Takao; Hori, Yuko; Ito, Katsunori; Nagahama, Kenji; Ozaki, Tomoko; Inoue, Naonori; Toda, Ryoko; Yoshii, Kazuyoshi; Hirayama, Masamichi; Kawabata, Yoshihiro; Takei, Mineo

2011-09-01

In clinical trials, acotiamide hydrochloride (acotiamide: Z-338) has been reported to be useful in the treatment of functional dyspepsia. Here, we investigated the effects of acotiamide on gastric contraction and emptying activities in rats in comparison with itopride hydrochloride (itopride) and mosapride citrate (mosapride). We also examined in vitro the compound's inhibitory effect on acetylcholinesterase (AChE) activity derived from rat stomach. In in vivo studies, acotiamide (30 and 100mg/kg s.c.) and itopride (100mg/kg s.c.) markedly enhanced normal gastric antral motility in rats. In gastric motility dysfunction models, acotiamide (100mg/kg s.c.) and itopride (100mg/kg s.c.) improved both gastric antral hypomotility and the delayed gastric emptying induced by clonidine, an α(2)-adrenoceptor agonist. In contrast, mosapride (10mg/kg s.c.) had no effect on these models. Like the AChE inhibitors itopride (30 mg/kg s.c.) and neostigmine (10 μg/kg s.c.), acotiamide (10mg/kg s.c.) also clearly enhanced gastric body contractions induced by electrical stimulation of the vagus, which were abolished by atropine and hexamethonium, whereas mosapride (3 and 10mg/kg s.c.) did not. In in vitro studies, acotiamide concentration-dependently inhibited rat stomach-derived AChE activity (IC(50)=2.3 μmol/l). In addition, stomach tissue concentrations of acotiamide after administration at 10mg/kg s.c. were sufficient to produce inhibition of AChE activity in rat stomach. These results suggest that acotiamide stimulates gastric motility and improves gastric motility dysfunction in rats by inhibiting AChE activity, and may suggest a role for acotiamide in improving gastric motility dysfunction in patients with functional dyspepsia. Copyright © 2011 Elsevier B.V. All rights reserved.

Abnormal intermediate filament organization alters mitochondrial motility in giant axonal neuropathy fibroblasts

PubMed Central

Lowery, Jason; Jain, Nikhil; Kuczmarski, Edward R.; Mahammad, Saleemulla; Goldman, Anne; Gelfand, Vladimir I.; Opal, Puneet; Goldman, Robert D.

2016-01-01

Giant axonal neuropathy (GAN) is a rare disease caused by mutations in the GAN gene, which encodes gigaxonin, an E3 ligase adapter that targets intermediate filament (IF) proteins for degradation in numerous cell types, including neurons and fibroblasts. The cellular hallmark of GAN pathology is the formation of large aggregates and bundles of IFs. In this study, we show that both the distribution and motility of mitochondria are altered in GAN fibroblasts and this is attributable to their association with vimentin IF aggregates and bundles. Transient expression of wild-type gigaxonin in GAN fibroblasts reduces the number of IF aggregates and bundles, restoring mitochondrial motility. Conversely, silencing the expression of gigaxonin in control fibroblasts leads to changes in IF organization similar to that of GAN patient fibroblasts and a coincident loss of mitochondrial motility. The inhibition of mitochondrial motility in GAN fibroblasts is not due to a global inhibition of organelle translocation, as lysosome motility is normal. Our findings demonstrate that it is the pathological changes in IF organization that cause the loss of mitochondrial motility. PMID:26700320

Intrinsic, Functional, and Structural Properties of β-Thymosins and β-Thymosin/WH2 Domains in the Regulation and Coordination of Actin Self-Assembly Dynamics and Cytoskeleton Remodeling.

PubMed

Renault, L

2016-01-01

β-Thymosins are a family of heat-stable multifunctional polypeptides that are expressed as small proteins of about 5kDa (~45 amino acids) almost exclusively in multicellular animals. They were first isolated from the thymus. As full-length or truncated polypeptides, they appear to stimulate a broad range of extracellular activities in various signaling pathways, including tissue repair and regeneration, inflammation, cell migration, and immune defense. However, their cell surface receptors and structural mechanisms of regulations in these multiple pathways remain still poorly understood. Besides their extracellular activities, they belong to a larger family of small, intrinsically disordered actin-binding domains called WH2/β-thymosin domains that have been identified in more than 1800 multidomain proteins found in different taxonomic domains of life and involved in various actin-based motile processes including cell morphogenesis, motility, adhesions, tissue development, intracellular trafficking, or pathogen infections. This review briefly surveys the main recent findings to understand how these small, intrinsically disordered but functional domains can interact with many unrelated partners and can thus integrate and coordinate various intracellular activities in actin self-assembly dynamics and cell signaling pathways linked to their cytoskeleton remodeling. © 2016 Elsevier Inc. All rights reserved.

Dietary n-6:n-3 ratio and Vitamin E improve motility characteristics in association with membrane properties of boar spermatozoa.

PubMed

Liu, Qing; Zhou, Yuan-Fei; Duan, Run-Jia; Wei, Hong-Kui; Peng, Jian; Jiang, Si-Wen

2017-01-01

This study was aimed to evaluate the effects of dietary n-6:n-3 ratio and Vitamin E on the membrane properties and motility characteristics of spermatozoa in boars. Forty Duroc boars were randomly distributed in a 2 × 2 factorial design with two n-6:n-3 ratios (14.4 and 6.6) and two Vitamin E levels (200 and 400 mg kg-1 ). During 16 weeks of treatment, fresh semen was collected at weeks 0, 8, 12, and 16 for measurements of motility characteristics, contents of fatty acids, membrane properties (membrane fluidity and membrane integrity), and lipid peroxidation of the spermatozoa. The semen was diluted in Beltsville Thawing Solution (BTS) extender and stored at 17°C, and the sperm motility was assessed at 12, 36, 72, and 120 h of storage. The 6.6 n-6:n-3 dietary ratio increased the contents of n-3 polyunsaturated fatty acids (PUFAs) and docosahexaenoic acid (DHA) and improved the membrane integrity and membrane fluidity of the spermatozoa, resulting in notably increased total motility, sperm progressive motility, and velocity parameters of fresh semen. Feeding diet with Vitamin E (400 mg kg-1 ) prevented sperm lipid peroxidation, and resulted in higher total motility and sperm progressive motility in fresh and liquid stored semen. In conclusion, the adjustment of n-6:n-3 ratio (6.6) and supply of Vitamin E (400 mg kg-1 ) successfully improved sperm motility characteristics and thus may be beneficial to the fertility of boars, which might be due to the modification of the physical and functional properties of spermatozoa membrane in response to dietary supplementation.

Dietary n-6:n-3 ratio and Vitamin E improve motility characteristics in association with membrane properties of boar spermatozoa

PubMed Central

Liu, Qing; Zhou, Yuan-Fei; Duan, Run-Jia; Wei, Hong-Kui; Peng, Jian; Jiang, Si-Wen

2017-01-01

This study was aimed to evaluate the effects of dietary n-6:n-3 ratio and Vitamin E on the membrane properties and motility characteristics of spermatozoa in boars. Forty Duroc boars were randomly distributed in a 2 × 2 factorial design with two n-6:n-3 ratios (14.4 and 6.6) and two Vitamin E levels (200 and 400 mg kg−1). During 16 weeks of treatment, fresh semen was collected at weeks 0, 8, 12, and 16 for measurements of motility characteristics, contents of fatty acids, membrane properties (membrane fluidity and membrane integrity), and lipid peroxidation of the spermatozoa. The semen was diluted in Beltsville Thawing Solution (BTS) extender and stored at 17°C, and the sperm motility was assessed at 12, 36, 72, and 120 h of storage. The 6.6 n-6:n-3 dietary ratio increased the contents of n-3 polyunsaturated fatty acids (PUFAs) and docosahexaenoic acid (DHA) and improved the membrane integrity and membrane fluidity of the spermatozoa, resulting in notably increased total motility, sperm progressive motility, and velocity parameters of fresh semen. Feeding diet with Vitamin E (400 mg kg−1) prevented sperm lipid peroxidation, and resulted in higher total motility and sperm progressive motility in fresh and liquid stored semen. In conclusion, the adjustment of n-6:n-3 ratio (6.6) and supply of Vitamin E (400 mg kg−1) successfully improved sperm motility characteristics and thus may be beneficial to the fertility of boars, which might be due to the modification of the physical and functional properties of spermatozoa membrane in response to dietary supplementation. PMID:26763547

Maturational changes in motility, acrosomal proteolytic activity, and penetrability of the inner perivitelline layer of fowl sperm, during their passage through the male genital tract.

PubMed

Ahammad, Muslah U; Nishino, C; Tatemoto, H; Okura, N; Kawamoto, Y; Okamoto, S; Nakada, T

2011-10-01

The objective was to examine, in vitro, the motility, acrosomal proteolytic activity (APA), and penetrating ability of fowl sperm recovered from the testis and epididymis, as well as the proximal, middle, and distal vas deferens, to assess the potential fertilizing ability of sperm as a function of maturation. A motile sperm separation technique was used to estimate sperm motility with Accudenz, a gelatin slide technique was used to measure the diameter of the halo around the acrosome of individual sperm as an indication of APA, and a sperm-inner perivitelline layer (IPL) interaction assay was done to estimate the number of hole formations as an indication of sperm penetration into the IPL. Sperm in the testis exhibited the least motility, produced the smallest halos, and created the least number of holes per 0.25 mm(2). Motility, diameter of the halo, and number of holes increased gradually (P < 0.05) from the epididymis to the distal vas deferens and were markedly different (P < 0.05) between testicular and deferent duct sperm. Based on these in vitro experimental findings, we inferred that fowl sperm undergo a gradual process of maturational changes in motility, APA, and penetrability as a means of acquiring potential fertility during their passage throughout the male genital tract. Copyright © 2011 Elsevier Inc. All rights reserved.

Toward the reconstitution of synthetic cell motility

PubMed Central

Siton-Mendelson, Orit; Bernheim-Groswasser, Anne

2016-01-01

ABSTRACT Cellular motility is a fundamental process essential for embryonic development, wound healing, immune responses, and tissues development. Cells are mostly moving by crawling on external, or inside, substrates which can differ in their surface composition, geometry, and dimensionality. Cells can adopt different migration phenotypes, e.g., bleb-based and protrusion-based, depending on myosin contractility, surface adhesion, and cell confinement. In the few past decades, research on cell motility has focused on uncovering the major molecular players and their order of events. Despite major progresses, our ability to infer on the collective behavior from the molecular properties remains a major challenge, especially because cell migration integrates numerous chemical and mechanical processes that are coupled via feedbacks that span over large range of time and length scales. For this reason, reconstituted model systems were developed. These systems allow for full control of the molecular constituents and various system parameters, thereby providing insight into their individual roles and functions. In this review we describe the various reconstituted model systems that were developed in the past decades. Because of the multiple steps involved in cell motility and the complexity of the overall process, most of the model systems focus on very specific aspects of the individual steps of cell motility. Here we describe the main advancement in cell motility reconstitution and discuss the main challenges toward the realization of a synthetic motile cell. PMID:27019160

Emerging Evidence on Neutrophil Motility Supporting Its Usefulness to Define Vitamin C Intake Requirements.

PubMed

Elste, Volker; Troesch, Barbara; Eggersdorfer, Manfred; Weber, Peter

2017-05-16

Establishing intake recommendations for vitamin C remains a challenge, as no suitable functional parameter has yet been agreed upon. In this report, we review the emerging evidence on neutrophil motility as a possible marker of vitamin C requirements and put the results in perspective with other approaches. A recent in vitro study showed that adequate levels of vitamin C were needed for this function to work optimally when measured as chemotaxis and chemokinesis. In a human study, neutrophil motility was optimal at intakes ≥250 mg/day. Interestingly, a Cochrane review showed a significant reduction in the duration of episodes of common cold with regular vitamin C intakes in a similar range. Additionally, it was shown that at a plasma level of 75 µmol/L, which is reached with vitamin C intakes ≥200 mg/day, incidences of cardiovascular disease were lowest. This evidence would suggest that daily intakes of 200 mg vitamin C might be advisable for the general adult population, which can be achieved by means of a diverse diet. However, additional studies are warranted to investigate the usefulness of neutrophil motility as a marker of vitamin C requirements.

Leishmania infection inhibits macrophage motility by altering F-actin dynamics and the expression of adhesion complex proteins

PubMed Central

de Menezes, Juliana Perrone Bezerra; Koushik, Amrita; Das, Satarupa; Guven, Can; Siegel, Ariel; Laranjeira-Silva, Maria Fernanda; Losert, Wolfgang; Andrews, Norma W.

2016-01-01

Leishmania is an intracellular protozoan parasite that causes a broad spectrum of clinical manifestations, ranging from self-healing skin lesions to fatal visceralizing disease. As the host cells of choice for all species of Leishmania, macrophages are critical for the establishment of infections. How macrophages contribute to parasite homing to specific tissues and how parasites modulate macrophage function is still poorly understood. In this study we show that L. amazonensis infection inhibits macrophage roaming motility. The reduction in macrophage speed is not dependent on particle load or on factors released by infected macrophages. L. amazonensis-infected macrophages also show reduced directional migration in response to the chemokine MCP-1. We found that infected macrophages have lower levels of total paxillin, phosphorylated paxillin and phosphorylated FAK when compared to non-infected macrophages, indicating abnormalities in the formation of signaling adhesion complexes that regulate motility. Analysis of the dynamics of actin polymerization at peripheral sites also revealed a markedly enhanced F-actin turnover frequency in L. amazonensis-infected macrophages. Thus, Leishmania infection inhibits macrophage motility by altering actin dynamics and impairing the expression of proteins that function in plasma membrane-extracellular matrix interactions. PMID:27641840

Extracellular calcium regulates protein tyrosine phosphorylation through calcium-sensing receptor (CaSR) in stallion sperm.

PubMed

Macías-García, Beatriz; Rocha, Antonio; González-Fernández, Lauro

2016-03-01

Protein tyrosine phosphorylation (PY), a hallmark of sperm capacitation, is inhibited by extracellular calcium in stallion sperm. The objective of this study was to determine the presence and influence of the calcium-sensing receptor (CaSR) in this phenomenon. First, the presence of the CaSR was demonstrated in stallion sperm. We then tested its function in these gametes using its inhibitor NPS2143 or its agonist AC34356. Sperm were capacitated for 4 hr in modified Whitten's medium with 25 mM bicarbonate plus NPS2143 and 2.4 mM calcium or AC34356 alone, followed by analysis of PY. Inhibition of CaSR with NPS2143 prevented the calcium-dependent PY inhibition in a dose-dependent manner (5, 10, and 15 μM) whereas AC34356 (100 μM) inhibited PY similarly to calcium. Stallion sperm motility and viability significantly decreased in presence of 15 μM of NPS2143 whereas only sperm motility decreased with 100 μM of AC34356. CaSR function was also studied in the complete absence of calcium by including 2 mM ethylene glycol tetraacetic acid (EGTA); under these conditions, AC34356 again inhibited PY, but this time induced a significant increase in sperm motility. Inhibition of calmodulin by W-7 did not recover the AC34356-mediated PY inhibition. When stallion sperm were incubated under capacitating conditions (calcium, bicarbonate, plus bovine serum albumin) at elevated pH (7.9 or 8.5) AC34356 did not block PY. These results thus elucidate the effect of extracellular conditions on the regulation of CaSR, and point to its modulatory role on stallion sperm PY, motility, and viability. Mol. Reprod. Dev. 83: 236-245, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effects of gum chewing on postoperative bowel motility after caesarean section: a meta-analysis of randomised controlled trials.

PubMed

Zhu, Y-P; Wang, W-J; Zhang, S-L; Dai, B; Ye, D-W

2014-06-01

Gum chewing has been reported to enhance bowel motility and reduce postoperative ileus (POI). However, the efficacy remains imprecise for women following caesarean section. To summarise and evaluate the current evidence for postoperative gum chewing on the recovery of bowel function following caesarean section. We searched studies from the following electronic databases: PubMed, EMBASE, SCOPUS and Cochrane Library from inception to 30 May 2013. We included randomised controlled trials (RCTs) of women after caesarean section; these RCTs should compared gum chewing with no gum chewing and reported on at least one of the outcomes: time to flatus, time to bowel sound, time to passing stool and length of hospital stay (LOS). Study outcomes were presented as mean differences (for continuous data) with 95% confidence interval (95% CI). The risk of bias in the study results was assessed using the assessment tool from the Cochrane Handbook. Six RCTs including 939 women were included in our meta-analysis. The pooled results demonstrated that gum chewing is superior to no gum chewing with a reduction of 6.42 hours (95% CI -7.55 to -5.29) for time to first flatus, 3.62 hours (95% CI -6.41 to -0.83) for time to first bowel sound, 6.58 hours (95% CI -10.10 to -3.07) for time to first stool and 5.94 hours (95% CI -9.39 to -2.49) for LOS. In addition, no evidence emerged for any side effects caused by gum chewing. The current evidence suggests that gum chewing is associated with early recovery of bowel motility and shorter LOS for women after caesarean section. This safe and inexpensive intervention should be included in routine postoperative care following a caesarean section. © 2014 Royal College of Obstetricians and Gynaecologists.

Presence and function of dopamine transporter (DAT) in stallion sperm: dopamine modulates sperm motility and acrosomal integrity.

PubMed

Urra, Javier A; Villaroel-Espíndola, Franz; Covarrubias, Alejandra A; Rodríguez-Gil, Joan Enric; Ramírez-Reveco, Alfredo; Concha, Ilona I

2014-01-01

Dopamine is a catecholamine with multiple physiological functions, playing a key role in nervous system; however its participation in reproductive processes and sperm physiology is controversial. High dopamine concentrations have been reported in different portions of the feminine and masculine reproductive tract, although the role fulfilled by this catecholamine in reproductive physiology is as yet unknown. We have previously shown that dopamine type 2 receptor is functional in boar sperm, suggesting that dopamine acts as a physiological modulator of sperm viability, capacitation and motility. In the present study, using immunodetection methods, we revealed the presence of several proteins important for the dopamine uptake and signalling in mammalian sperm, specifically monoamine transporters as dopamine (DAT), serotonin (SERT) and norepinephrine (NET) transporters in equine sperm. We also demonstrated for the first time in equine sperm a functional dopamine transporter using 4-[4-(Dimethylamino)styryl]-N-methylpyridinium iodide (ASP(+)), as substrate. In addition, we also showed that dopamine (1 mM) treatment in vitro, does not affect sperm viability but decreases total and progressive sperm motility. This effect is reversed by blocking the dopamine transporter with the selective inhibitor vanoxerine (GBR12909) and non-selective inhibitors of dopamine reuptake such as nomifensine and bupropion. The effect of dopamine in sperm physiology was evaluated and we demonstrated that acrosome integrity and thyrosine phosphorylation in equine sperm is significantly reduced at high concentrations of this catecholamine. In summary, our results revealed the presence of monoamine transporter DAT, NET and SERT in equine sperm, and that the dopamine uptake by DAT can regulate sperm function, specifically acrosomal integrity and sperm motility.

Presence and Function of Dopamine Transporter (DAT) in Stallion Sperm: Dopamine Modulates Sperm Motility and Acrosomal Integrity

PubMed Central

Covarrubias, Alejandra A.; Rodríguez-Gil, Joan Enric; Ramírez-Reveco, Alfredo; Concha, Ilona I.

2014-01-01

Dopamine is a catecholamine with multiple physiological functions, playing a key role in nervous system; however its participation in reproductive processes and sperm physiology is controversial. High dopamine concentrations have been reported in different portions of the feminine and masculine reproductive tract, although the role fulfilled by this catecholamine in reproductive physiology is as yet unknown. We have previously shown that dopamine type 2 receptor is functional in boar sperm, suggesting that dopamine acts as a physiological modulator of sperm viability, capacitation and motility. In the present study, using immunodetection methods, we revealed the presence of several proteins important for the dopamine uptake and signalling in mammalian sperm, specifically monoamine transporters as dopamine (DAT), serotonin (SERT) and norepinephrine (NET) transporters in equine sperm. We also demonstrated for the first time in equine sperm a functional dopamine transporter using 4-[4-(Dimethylamino)styryl]-N-methylpyridinium iodide (ASP+), as substrate. In addition, we also showed that dopamine (1 mM) treatment in vitro, does not affect sperm viability but decreases total and progressive sperm motility. This effect is reversed by blocking the dopamine transporter with the selective inhibitor vanoxerine (GBR12909) and non-selective inhibitors of dopamine reuptake such as nomifensine and bupropion. The effect of dopamine in sperm physiology was evaluated and we demonstrated that acrosome integrity and thyrosine phosphorylation in equine sperm is significantly reduced at high concentrations of this catecholamine. In summary, our results revealed the presence of monoamine transporter DAT, NET and SERT in equine sperm, and that the dopamine uptake by DAT can regulate sperm function, specifically acrosomal integrity and sperm motility. PMID:25402186

Development of a Novel Method for Analyzing Pseudomonas aeruginosa Twitching Motility and Its Application to Define the AmrZ Regulon

PubMed Central

Xu, Binjie; Wozniak, Daniel J.

2015-01-01

Twitching motility is an important migration mechanism for the Gram-negative bacterium Pseudomonas aeruginosa. In the commonly used subsurface twitching assay, the sub-population of P. aeruginosa with active twitching motility is difficult to harvest for high-throughput studies. Here we describe the development of a novel method that allows efficient isolation of bacterial sub-populations conducting highly active twitching motility. The transcription factor AmrZ regulates multiple P. aeruginosa virulence factors including twitching motility, yet the mechanism of this activation remains unclear. We therefore set out to understand this mechanism by defining the AmrZ regulon using DNA microarrays in combination with the newly developed twitching motility method. We discovered 112 genes in the AmrZ regulon and many encode virulence factors. One gene of interest and the subsequent focus was lecB, which encodes a fucose-binding lectin. DNA binding assays revealed that AmrZ activates lecB transcription by directly binding to its promoter. The lecB gene was previously shown to be required for twitching motility in P. aeruginosa strain PAK; however, our lecB deletion had no effect on twitching motility in strain PAO1. Collectively, in this study a novel condition was developed for quantitative studies of twitching motility, under which the AmrZ regulon was defined. PMID:26309248

A Putative O-Linked β-N-Acetylglucosamine Transferase Is Essential for Hormogonium Development and Motility in the Filamentous Cyanobacterium Nostoc punctiforme.

PubMed

Khayatan, Behzad; Bains, Divleen K; Cheng, Monica H; Cho, Ye Won; Huynh, Jessica; Kim, Rachelle; Omoruyi, Osagie H; Pantoja, Adriana P; Park, Jun Sang; Peng, Julia K; Splitt, Samantha D; Tian, Mason Y; Risser, Douglas D

2017-05-01

Most species of filamentous cyanobacteria are capable of gliding motility, likely via a conserved type IV pilus-like system that may also secrete a motility-associated polysaccharide. In a subset of these organisms, motility is achieved only after the transient differentiation of hormogonia, which are specialized filaments that enter a nongrowth state dedicated to motility. Despite the fundamental importance of hormogonia to the life cycles of many filamentous cyanobacteria, the molecular regulation of hormogonium development is largely undefined. To systematically identify genes essential for hormogonium development and motility in the model heterocyst-forming filamentous cyanobacterium Nostoc punctiforme , a forward genetic screen was employed. The first gene identified using this screen, designated ogtA , encodes a putative O-linked β- N -acetylglucosamine transferase (OGT). The deletion of ogtA abolished motility, while ectopic expression of ogtA induced hormogonium development even under hormogonium-repressing conditions. Transcription of ogtA is rapidly upregulated (1 h) following hormogonium induction, and an OgtA-GFPuv fusion protein localized to the cytoplasm. In developing hormogonia, accumulation of PilA but not HmpD is dependent on ogtA Reverse transcription-quantitative PCR (RT-qPCR) analysis indicated equivalent levels of pilA transcript in the wild-type and Δ ogtA mutant strains, while a reporter construct consisting of the intergenic region in the 5' direction of pilA fused to gfp produced lower levels of fluorescence in the Δ ogtA mutant strain than in the wild type. The production of hormogonium polysaccharide in the Δ ogtA mutant strain is reduced compared to that in the wild type but comparable to that in a pilA deletion strain. Collectively, these results imply that O -GlcNAc protein modification regulates the accumulation of PilA via a posttranscriptional mechanism in developing hormogonia. IMPORTANCE Filamentous cyanobacteria are among the most developmentally complex prokaryotes. Species such as Nostoc punctiforme develop an array of cell types, including nitrogen-fixing heterocysts, spore-like akinetes, and motile hormogonia, that function in dispersal as well as the establishment of nitrogen-fixing symbioses with plants and fungi. These symbioses are major contributors to global nitrogen fixation. Despite the fundamental importance of hormogonia to the life cycle of filamentous cyanobacteria and the establishment of symbioses, the molecular regulation of hormogonium development is largely undefined. We employed a genetic screen to identify genes essential for hormogonium development and motility in Nostoc punctiforme The first gene identified using this screen encodes a eukaryotic-like O-linked β- N -acetylglucosamine transferase that is required for accumulation of PilA in hormogonia. Copyright © 2017 American Society for Microbiology.

MotD of Sinorhizobium meliloti and Related α-Proteobacteria Is the Flagellar-Hook-Length Regulator and Therefore Reassigned as FliK

PubMed Central

Eggenhofer, Elke; Rachel, Reinhard; Haslbeck, Martin; Scharf, Birgit

2006-01-01

The flagella of the soil bacterium Sinorhizobium meliloti differ from the enterobacterial paradigm in the complex filament structure and modulation of the flagellar rotary speed. The mode of motility control in S. meliloti has a molecular corollary in two novel periplasmic motility proteins, MotC and MotE, that are present in addition to the ubiquitous MotA/MotB energizing proton channel. A fifth motility gene is located in the mot operon downstream of the motB and motC genes. Its gene product was originally designated MotD, a cytoplasmic motility protein having an unknown function. We report here reassignment of MotD as FliK, the regulator of flagellar hook length. The FliK gene is one of the few flagellar genes not annotated in the contiguous flagellar regulon of S. meliloti. Characteristic for its class, the 475-residue FliK protein contains a conserved, compactly folded Flg hook domain in its carboxy-terminal region. Deletion of fliK leads to formation of prolonged flagellar hooks (polyhooks) with missing filament structures. Extragenic suppressor mutations all mapped in the cytoplasmic region of the transmembrane export protein FlhB and restored assembly of a flagellar filament, and thus motility, in the presence of polyhooks. The structural properties of FliK are consistent with its function as a substrate specificity switch of the flagellar export apparatus for switching from rod/hook-type substrates to filament-type substrates. PMID:16513744

Kinesin-1 and mitochondrial motility control by discrimination of structurally equivalent but distinct subdomains in Ran-GTP-binding domains of Ran-binding protein 2.

PubMed

Patil, Hemangi; Cho, Kyoung-in; Lee, James; Yang, Yi; Orry, Andrew; Ferreira, Paulo A

2013-03-27

The pleckstrin homology (PH) domain is a versatile fold that mediates a variety of protein-protein and protein-phosphatidylinositol lipid interactions. The Ran-binding protein 2 (RanBP2) contains four interspersed Ran GTPase-binding domains (RBD(n = 1-4)) with close structural homology to the PH domain of Bruton's tyrosine kinase. The RBD2, kinesin-binding domain (KBD) and RBD3 comprise a tripartite domain (R2KR3) of RanBP2 that causes the unfolding, microtubule binding and biphasic activation of kinesin-1, a crucial anterograde motor of mitochondrial motility. However, the interplay between Ran GTPase and R2KR3 of RanBP2 in kinesin-1 activation and mitochondrial motility is elusive. We use structure-function, biochemical, kinetic and cell-based assays with time-lapse live-cell microscopy of over 260,000 mitochondrial-motility-related events to find mutually exclusive subdomains in RBD2 and RBD3 towards Ran GTPase binding, kinesin-1 activation and mitochondrial motility regulation. The RBD2 and RBD3 exhibit Ran-GTP-independent, subdomain and stereochemical-dependent discrimination on the biphasic kinetics of kinesin-1 activation or regulation of mitochondrial motility. Further, KBD alone and R2KR3 stimulate and suppress, respectively, multiple biophysical parameters of mitochondrial motility. The regulation of the bidirectional transport of mitochondria by either KBD or R2KR3 is highly coordinated, because their kinetic effects are accompanied always by changes in mitochondrial motile events of either transport polarity. These studies uncover novel roles in Ran GTPase-independent subdomains of RBD2 and RBD3, and KBD of RanBP2, that confer antagonizing and multi-modal mechanisms of kinesin-1 activation and regulation of mitochondrial motility. These findings open new venues towards the pharmacological harnessing of cooperative and competitive mechanisms regulating kinesins, RanBP2 or mitochondrial motility in disparate human disorders.

Increased count, motility, and total motile sperm cells collected across three consecutive ejaculations within 24 h of oocyte retrieval: implications for management of men presenting with low numbers of motile sperm for assisted reproduction.

PubMed

Said, Al-Hasen; Reed, Michael L

2015-07-01

The purpose of this study was to quantitate changes in seminal volume, sperm count, motility, qualitative forward progression, and total motile sperm cells per ejaculate, across three consecutive ejaculates collected from individuals within 24 h preceding an IVF cycle. Men presenting with oligoasthenozoospermia or asthenozoospemia attempted three ejaculates within 24 h preceding IVF. Ejaculate 1 was produced the afternoon prior to oocyte retrieval, and ejaculates 2 and 3 were produced the morning of oocyte retrieval with 2-3 h between collections. Ejaculates 1 and 2 were extended 1:1 v/v with room temperature rTYBS. Test tubes were placed into a beaker of room temperature water, then placed at 4 °C for gradual cooling. Ejaculate 3 was not extended, but pooled with ejaculates 1 and 2 and processed for intracytoplasmic sperm injection (ICSI). Out of 109 oocyte retrievals, 28 men were asked to attempt multiple consecutive ejaculations. Among this population, 25/28 (89.3 %) were successful, and 3/28 men (10.7 %) could only produce two ejaculates. Mean volumes for ejaculates 1, 2, and 3 were significantly different from each other (p < 0.01); the volume decreased for each ejaculate. Mean sperm counts, motility, qualitative forward progression, and total motile cells per ejaculate for the ejaculates1, 2, and 3 demonstrated the following: ejaculates 2 and 3 were not significantly different, but counts, motility, and total motile sperm were improved over ejaculate 1 (p < 0.01). Pooling three consecutive ejaculates within 24 h increased the numbers of available motile sperm in this population by 8-fold compared to the first ejaculate alone, facilitating avoidance of sperm cryopreservation and additional centrifugation steps that could affect sperm viability and/or function.

Functional trait responses to sediment deposition reduce macrofauna-mediated ecosystem functioning in an estuarine mudflat

NASA Astrophysics Data System (ADS)

Mestdagh, Sebastiaan; Bagaço, Leila; Braeckman, Ulrike; Ysebaert, Tom; De Smet, Bart; Moens, Tom; Van Colen, Carl

2018-05-01

Human activities, among which dredging and land use change in river basins, are altering estuarine ecosystems. These activities may result in changes in sedimentary processes, affecting biodiversity of sediment macrofauna. As macrofauna controls sediment chemistry and fluxes of energy and matter between water column and sediment, changes in the structure of macrobenthic communities could affect the functioning of an entire ecosystem. We assessed the impact of sediment deposition on intertidal macrobenthic communities and on rates of an important ecosystem function, i.e. sediment community oxygen consumption (SCOC). An experiment was performed with undisturbed sediment samples from the Scheldt river estuary (SW Netherlands). The samples were subjected to four sedimentation regimes: one control and three with a deposited sediment layer of 1, 2 or 5 cm. Oxygen consumption was measured during incubation at ambient temperature. Luminophores applied at the surface, and a seawater-bromide mixture, served as tracers for bioturbation and bio-irrigation, respectively. After incubation, the macrofauna was extracted, identified, and counted and then classified into functional groups based on motility and sediment reworking capacity. Total macrofaunal densities dropped already under the thinnest deposits. The most affected fauna were surficial and low-motility animals, occurring at high densities in the control. Their mortality resulted in a drop in SCOC, which decreased steadily with increasing deposit thickness, while bio-irrigation and bioturbation activity showed increases in the lower sediment deposition regimes but decreases in the more extreme treatments. The initial increased activity likely counteracted the effects of the drop in low-motility, surficial fauna densities, resulting in a steady rather than sudden fall in oxygen consumption. We conclude that the functional identity in terms of motility and sediment reworking can be crucial in our understanding of the regulation of ecosystem functioning and the impact of habitat alterations such as sediment deposition.

CASAnova: a multiclass support vector machine model for the classification of human sperm motility patterns.

PubMed

Goodson, Summer G; White, Sarah; Stevans, Alicia M; Bhat, Sanjana; Kao, Chia-Yu; Jaworski, Scott; Marlowe, Tamara R; Kohlmeier, Martin; McMillan, Leonard; Zeisel, Steven H; O'Brien, Deborah A

2017-11-01

The ability to accurately monitor alterations in sperm motility is paramount to understanding multiple genetic and biochemical perturbations impacting normal fertilization. Computer-aided sperm analysis (CASA) of human sperm typically reports motile percentage and kinematic parameters at the population level, and uses kinematic gating methods to identify subpopulations such as progressive or hyperactivated sperm. The goal of this study was to develop an automated method that classifies all patterns of human sperm motility during in vitro capacitation following the removal of seminal plasma. We visually classified CASA tracks of 2817 sperm from 18 individuals and used a support vector machine-based decision tree to compute four hyperplanes that separate five classes based on their kinematic parameters. We then developed a web-based program, CASAnova, which applies these equations sequentially to assign a single classification to each motile sperm. Vigorous sperm are classified as progressive, intermediate, or hyperactivated, and nonvigorous sperm as slow or weakly motile. This program correctly classifies sperm motility into one of five classes with an overall accuracy of 89.9%. Application of CASAnova to capacitating sperm populations showed a shift from predominantly linear patterns of motility at initial time points to more vigorous patterns, including hyperactivated motility, as capacitation proceeds. Both intermediate and hyperactivated motility patterns were largely eliminated when sperm were incubated in noncapacitating medium, demonstrating the sensitivity of this method. The five CASAnova classifications are distinctive and reflect kinetic parameters of washed human sperm, providing an accurate, quantitative, and high-throughput method for monitoring alterations in motility. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

DNA-assisted swarm control in a biomolecular motor system.

PubMed

Keya, Jakia Jannat; Suzuki, Ryuhei; Kabir, Arif Md Rashedul; Inoue, Daisuke; Asanuma, Hiroyuki; Sada, Kazuki; Hess, Henry; Kuzuya, Akinori; Kakugo, Akira

2018-01-31

In nature, swarming behavior has evolved repeatedly among motile organisms because it confers a variety of beneficial emergent properties. These include improved information gathering, protection from predators, and resource utilization. Some organisms, e.g., locusts, switch between solitary and swarm behavior in response to external stimuli. Aspects of swarming behavior have been demonstrated for motile supramolecular systems composed of biomolecular motors and cytoskeletal filaments, where cross-linkers induce large scale organization. The capabilities of such supramolecular systems may be further extended if the swarming behavior can be programmed and controlled. Here, we demonstrate that the swarming of DNA-functionalized microtubules (MTs) propelled by surface-adhered kinesin motors can be programmed and reversibly regulated by DNA signals. Emergent swarm behavior, such as translational and circular motion, can be selected by tuning the MT stiffness. Photoresponsive DNA containing azobenzene groups enables switching between solitary and swarm behavior in response to stimulation with visible or ultraviolet light.

Honey Attenuates the Detrimental Effects of Nicotine on Testicular Functions in Nicotine Treated Wistar Rats.

PubMed

Kolawole, T A; Oyeyemi, W A; Adigwe, C; Leko, B; Udeh, C; Dapper, D V

2015-12-20

Effect of honey on reproductive functions of male rats exposed to nicotine was examined in this study. Thirty-two adult male wistar rats (n=8/Group) were grouped as Control (distilled water), Nicotine (1.0mg/kg bwt), Honey (100mg/kg bwt) and Nicotine with Honey. The animals were orally treated for 35 days consecutively. Epididymis sperm motility, viability, morphology and counts were estimated, serum Follicle Stimulating Hormone (FSH), Leutinizing Hormone (LH) and Testosterone were assayed using ELISA method and testicular histology were also assessed. Significant reduction in percentage sperm motility, viability, morphology and counts were observed in nicotine group compared to control. Serum FSH, LH and testosterone levels were significantly reduced in nicotine group when compared with the control. There was significant improvement in sperm motility, viability, morphology, counts, FSH, LH and Testosterone in group co-treated with nicotine and honey  relative to nicotine group. Also, the degenerative seminiferous tubule architecture due to nicotine was improved by honey. In conclusion, honey may suppress nicotine toxic effect on reproductive functions in male Wistar rats.

Slits Affect the Timely Migration of Neural Crest Cells via Robo Receptor

PubMed Central

Giovannone, Dion; Reyes, Michelle; Reyes, Rachel; Correa, Lisa; Martinez, Darwin; Ra, Hannah; Gomez, Gustavo; Kaiser, Josh; Ma, Le; Stein, Mary-Pat; de Bellard, Maria Elena

2013-01-01

SUMMARY Background Neural crest cells emerge by delamination from the dorsal neural tube and give rise to various components of the peripheral nervous system in vertebrate embryos. These cells change from non-motile into highly motile cells migrating to distant areas before further differentiation. Mechanisms controlling delamination and subsequent migration of neural crest cells are not fully understood. Slit2, a chemorepellant for axonal guidance that repels and stimulates motility of trunk neural crest cells away from the gut has recently been suggested to be a tumor suppressor molecule. The goal of this study was to further investigate the role of Slit2 in trunk neural crest cell migration by constitutive expression in neural crest cells. Results We found that Slit gain-of-function significantly impaired neural crest cell migration while Slit loss-of-function favored migration. In addition, we observed that the distribution of key cytoskeletal markers was disrupted in both gain and loss of function instances. Conclusions These findings suggest that Slit molecules might be involved in the processes that allow neural crest cells to begin migration and transitioning to a mesenchymal type. PMID:22689303

Rhizobial galactoglucan determines the predatory pattern of Myxococcus xanthus and protects Sinorhizobium meliloti from predation

PubMed Central

Pérez, Juana; Jiménez-Zurdo, José I.; Martínez-Abarca, Francisco; Millán, Vicenta; Shimkets, Lawrence J.; Muñoz-Dorado, José

2014-01-01

Summary Myxococcus xanthus is a social bacterium that preys on prokaryotic and eukaryotic microorganisms. Co-culture of M. xanthus with reference laboratory strains and field isolates of the legume symbiont Sinorhizobium meliloti revealed two different predatory patterns that resemble frontal and wolfpack attacks. Use of mutants impaired in the two types of M. xanthus surface motility (A or adventurous and S or social motility) and a csgA mutant, which is unable to form macroscopic travelling waves known as ripples, has demonstrated that both motility systems but not rippling are required for efficient predation. To avoid frontal attack and reduce killing rates, rhizobial cells require a functional expR gene. ExpR regulates expression of genes involved in a variety of functions. The use of S. meliloti mutants impaired in several of these functions revealed that the exopolysaccharide galactoglucan (EPS II) is the major determinant of the M. xanthus predatory pattern. The data also suggest that this biopolymer confers an ecological advantage to rhizobial survival in soil, which may have broad environmental implications. PMID:24707988

A systematic analysis of the in vitro and in vivo functions of the HD-GYP domain proteins of Vibrio cholerae.

PubMed

McKee, Robert W; Kariisa, Ankunda; Mudrak, Benjamin; Whitaker, Courtney; Tamayo, Rita

2014-10-25

The second messenger cyclic diguanylate (c-di-GMP) plays a central role in bacterial adaptation to extracellular stimuli, controlling processes such as motility, biofilm development, cell development and, in some pathogens, virulence. The intracellular level of c-di-GMP is controlled by the complementary activities of diguanylate cyclases containing a GGDEF domain and two classes of c-di-GMP phosphodiesterases containing an EAL or HD-GYP hydrolytic domain. Compared to the GGDEF and EAL domains, the functions of HD-GYP domain family proteins are poorly characterized. The human diarrheal pathogen Vibrio cholerae encodes nine putative HD-GYP domain proteins. To determine the contributions of HD-GYP domain proteins to c-di-GMP signaling in V. cholerae, we systematically analyzed the enzymatic functionality of each protein and their involvement in processes known to be regulated by c-di-GMP: motility, biofilm development and virulence. Complementary in vitro and in vivo experiments showed that four HD-GYP domain proteins are active c-di-GMP phosphodiesterases: VC1295, VC1348, VCA0210 and VCA0681. Mutation of individual HD-GYP domain genes, as well as combinatorial mutations of multiple HD-GYP domain genes, had no effect on motility or biofilm formation of V. cholerae under the conditions tested. Furthermore, no single HD-GYP domain gene affected intestinal colonization by V. cholerae in an infant mouse model. However, inactivation of multiple HD-GYP domain genes, including the four encoding functional phosphodiesterases, significantly attenuated colonization. These results indicate that the HD-GYP family of c-di-GMP phosphodiesterases impacts signaling by this second messenger during infection. Altogether, this work greatly furthers the understanding of this important family of c-di-GMP metabolic enzymes and demonstrates a role for HD-GYP domain proteins in the virulence of V. cholerae.

Evolution and Design Governing Signal Precision and Amplification in a Bacterial Chemosensory Pathway

PubMed Central

Espinosa, Leon; Baronian, Grégory; Molle, Virginie; Mauriello, Emilia M. F.; Brochier-Armanet, Céline; Mignot, Tâm

2015-01-01

Understanding the principles underlying the plasticity of signal transduction networks is fundamental to decipher the functioning of living cells. In Myxococcus xanthus, a particular chemosensory system (Frz) coordinates the activity of two separate motility systems (the A- and S-motility systems), promoting multicellular development. This unusual structure asks how signal is transduced in a branched signal transduction pathway. Using combined evolution-guided and single cell approaches, we successfully uncoupled the regulations and showed that the A-motility regulation system branched-off an existing signaling system that initially only controlled S-motility. Pathway branching emerged in part following a gene duplication event and changes in the circuit structure increasing the signaling efficiency. In the evolved pathway, the Frz histidine kinase generates a steep biphasic response to increasing external stimulations, which is essential for signal partitioning to the motility systems. We further show that this behavior results from the action of two accessory response regulator proteins that act independently to filter and amplify signals from the upstream kinase. Thus, signal amplification loops may underlie the emergence of new connectivity in signal transduction pathways. PMID:26291327

betaPIX controls cell motility and neurite extension by regulating the distribution of GIT1.

PubMed

Za, Lorena; Albertinazzi, Chiara; Paris, Simona; Gagliani, Mariacristina; Tacchetti, Carlo; de Curtis, Ivan

2006-07-01

Cell motility entails the reorganization of the cytoskeleton and membrane trafficking for effective protrusion. GIT1/p95-APP1 is a member of a family of GTPase-activating proteins for ARF GTPases that affect endocytosis, adhesion and migration. GIT1 associates with paxillin and a complex including the Rac/Cdc42 exchanging factors PIX/Cool and the kinase PAK. In this study, we show that overexpression of betaPIX induces the accumulation of endogenous and overexpressed GIT1 at large structures similar to those induced by an ArfGAP-defective mutant of GIT1 (p95-C2). Immunohistochemical analysis and immunoelectron microscopy reveal that these structures include the endogenous transferrin receptor. Time-lapse analysis during motogenic stimuli shows that the formation and perinuclear accumulation of the p95-C2-positive structures is paralleled by inhibition of lamellipodium formation and cell retraction. Both dimerization and a functional SH3 domain of betaPIX are required for the accumulation of GIT1 in fibroblasts, which is prevented by the monomeric PIX-PG-DeltaLZ. This mutant also prevents the formation of endocytic aggregates and inhibition of neurite outgrowth in retinal neurons expressing p95-C2. Our results indicate that betaPIX is an important regulator of the subcellular distribution of GIT1, and suggest that alteration in the level of expression of the complex affects the endocytic compartment and cell motility.

A minimal physical model for crawling cells

NASA Astrophysics Data System (ADS)

Tiribocchi, Adriano; Tjhung, Elsen; Marenduzzo, Davide; Cates, Michael E.

Cell motility in higher organisms (eukaryotes) is fundamental to biological functions such as wound healing or immune response, and is also implicated in diseases such as cancer. For cells crawling on solid surfaces, considerable insights into motility have been gained from experiments replicating such motion in vitro. Such experiments show that crawling uses a combination of actin treadmilling (polymerization), which pushes the front of a cell forward, and myosin-induced stress (contractility), which retracts the rear. We present a simplified physical model of a crawling cell, consisting of a droplet of active polar fluid with contractility throughout, but treadmilling connected to a thin layer near the supporting wall. The model shows a variety of shapes and/or motility regimes, some closely resembling cases seen experimentally. Our work supports the view that cellular motility exploits autonomous physical mechanisms whose operation does not need continuous regulatory effort.

A minimal physical model captures the shapes of crawling cells

NASA Astrophysics Data System (ADS)

Tjhung, E.; Tiribocchi, A.; Marenduzzo, D.; Cates, M. E.

2015-01-01

Cell motility in higher organisms (eukaryotes) is crucial to biological functions ranging from wound healing to immune response, and also implicated in diseases such as cancer. For cells crawling on hard surfaces, significant insights into motility have been gained from experiments replicating such motion in vitro. Such experiments show that crawling uses a combination of actin treadmilling (polymerization), which pushes the front of a cell forward, and myosin-induced stress (contractility), which retracts the rear. Here we present a simplified physical model of a crawling cell, consisting of a droplet of active polar fluid with contractility throughout, but treadmilling connected to a thin layer near the supporting wall. The model shows a variety of shapes and/or motility regimes, some closely resembling cases seen experimentally. Our work strongly supports the view that cellular motility exploits autonomous physical mechanisms whose operation does not need continuous regulatory effort.

Quantitative in vivo whole genome motility screen reveals novel therapeutic targets to block cancer metastasis.

PubMed

Stoletov, Konstantin; Willetts, Lian; Paproski, Robert J; Bond, David J; Raha, Srijan; Jovel, Juan; Adam, Benjamin; Robertson, Amy E; Wong, Francis; Woolner, Emma; Sosnowski, Deborah L; Bismar, Tarek A; Wong, Gane Ka-Shu; Zijlstra, Andries; Lewis, John D

2018-06-14

Metastasis is the most lethal aspect of cancer, yet current therapeutic strategies do not target its key rate-limiting steps. We have previously shown that the entry of cancer cells into the blood stream, or intravasation, is highly dependent upon in vivo cancer cell motility, making it an attractive therapeutic target. To systemically identify genes required for tumor cell motility in an in vivo tumor microenvironment, we established a novel quantitative in vivo screening platform based on intravital imaging of human cancer metastasis in ex ovo avian embryos. Utilizing this platform to screen a genome-wide shRNA library, we identified a panel of novel genes whose function is required for productive cancer cell motility in vivo, and whose expression is closely associated with metastatic risk in human cancers. The RNAi-mediated inhibition of these gene targets resulted in a nearly total (>99.5%) block of spontaneous cancer metastasis in vivo.

Using experimental evolution to explore natural patterns between bacterial motility and resistance to bacteriophages

PubMed Central

Koskella, Britt; Taylor, Tiffany B; Bates, Jennifer; Buckling, Angus

2011-01-01

Resistance of bacteria to phages may be gained by alteration of surface proteins to which phages bind, a mechanism that is likely to be costly as these molecules typically have critical functions such as movement or nutrient uptake. To address this potential trade-off, we combine a systematic study of natural bacteria and phage populations with an experimental evolution approach. We compare motility, growth rate and susceptibility to local phages for 80 bacteria isolated from horse chestnut leaves and, contrary to expectation, find no negative association between resistance to phages and bacterial motility or growth rate. However, because correlational patterns (and their absence) are open to numerous interpretations, we test for any causal association between resistance to phages and bacterial motility using experimental evolution of a subset of bacteria in both the presence and absence of naturally associated phages. Again, we find no clear link between the acquisition of resistance and bacterial motility, suggesting that for these natural bacterial populations, phage-mediated selection is unlikely to shape bacterial motility, a key fitness trait for many bacteria in the phyllosphere. The agreement between the observed natural pattern and the experimental evolution results presented here demonstrates the power of this combined approach for testing evolutionary trade-offs. PMID:21509046

Effects of intermediate frequency magnetic fields on male fertility indicators in mice.

PubMed

Kumari, K; Capstick, M; Cassara, A M; Herrala, M; Koivisto, H; Naarala, J; Tanila, H; Viluksela, M; Juutilainen, J

2017-08-01

Human exposure to intermediate frequency (IF) fields is increasing due to new applications such as electronic article surveillance systems, wireless power transfer and induction heating cookers. However, limited data is available on effects of IF magnetic fields (MF) on male fertility function. This study was conducted to assess possible effects on fertility indicators from exposure to IF MF. Male C57BL/6J mice were exposed continuously for 5 weeks to 7.5kHz MF at 12 and 120μT. Sperm cells from cauda epididymis were analysed for motility, total sperm counts, and head abnormalities. Motile sperm cells were classified as progressive or non-progressive. Testicular spermatid heads were counted as well. The body weight development and reproductive tissue weights were not affected. No exposure-related differences were observed in sperm counts or sperm head abnormalities. Proportion of non-motile cells was significantly decreased in the 120µT group, and a corresponding increase was seen in the percentage of motile cells (significant in non-progressive motile cells). In conclusion, no adverse effects on fertility indicators were observed. Increased sperm motility is an interesting finding that needs to be confirmed in further studies. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Sorbitol Can Fuel Mouse Sperm Motility and Protein Tyrosine Phosphorylation via Sorbitol Dehydrogenase1

PubMed Central

Cao, Wenlei; Aghajanian, Haig K.; Haig-Ladewig, Lisa A.; Gerton, George L.

2008-01-01

Energy sources that can be metabolized to yield ATP are essential for normal sperm functions such as motility. Two major monosaccharides, sorbitol and fructose, are present in semen. Furthermore, sorbitol dehydrogenase (SORD) can convert sorbitol to fructose, which can then be metabolized via the glycolytic pathway in sperm to make ATP. Here we characterize Sord mRNA and SORD expression during mouse spermatogenesis and examine the ability of sorbitol to support epididymal sperm motility and tyrosine phosphorylation. Sord mRNA levels increased during the course of spermatogenic differentiation. SORD protein, however, was first detected at the condensing spermatid stage. By indirect immunofluorescence, SORD was present along the length of the flagella of caudal epididymal sperm. Furthermore, immunoelectron microscopy showed that SORD was associated with mitochondria and the plasma membranes of sperm. Sperm incubated with sorbitol maintained motility, indicating that sorbitol was utilized as an energy source. Sorbitol, as well as glucose and fructose, were not essential to induce hyperactive motility. Protein tyrosine phosphorylation increased in a similar manner when sorbitol was substituted for glucose in the incubation medium used for sperm capacitation. These results indicate that sorbitol can serve as an alternative energy source for sperm motility and protein tyrosine phosphorylation. PMID:18799757

Isolation, characterization, and complementation of a motility mutant of Spiroplasma citri.

PubMed Central

Jacob, C; Nouzières, F; Duret, S; Bové, J M; Renaudin, J

1997-01-01

The helical mollicute Spiroplasma citri, when growing on low-agar medium, forms fuzzy colonies with occasional surrounding satellite colonies due to the ability of the spiroplasmal cells to move through the agar matrix. In liquid medium, these helical organisms flex, twist, and rotate rapidly. By using Tn4001 insertion mutagenesis, a motility mutant was isolated on the basis of its nondiffuse, sharp-edged colonies. Dark-field microscopy observations revealed that the organism flexed at a low frequency and had lost the ability to rotate about the helix axis. In this mutant, the transposon was shown to be inserted into an open reading frame encoding a putative polypeptide of 409 amino acids for which no significant homology with known proteins was found. The corresponding gene, named scm1, was recovered from the wild-type strain and introduced into the motility mutant by using the S. citri oriC plasmid pBOT1 as the vector. The appearance of fuzzy colonies and the observation that spiroplasma cells displayed rotatory and flexional movements showed the motile phenotype to be restored in the spiroplasmal transformants. The functional complementation of the motility mutant proves the scm1 gene product to be involved in the motility mechanism of S. citri. PMID:9244268

Prevalence and Impact of Late Defecation in the Critically Ill, Thermally Injured Adult Patient

DTIC Science & Technology

2014-01-01

retention and maintain weight.12 The enteral feeding formula we provide is high in protein and carbohydrate and low in fat. Nutritional adequacy is...myriad of complex functions the GI tract must perform to maintain homeostasis to include: motility, absorption, endo- crinologic aspects... nutrition in the criti- cally ill adult have been well established, and current guidelines advocate beginning enteral feeding within 24 to 48 hours of

Gliding Motility and Por Secretion System Genes Are Widespread among Members of the Phylum Bacteroidetes

PubMed Central

Zhu, Yongtao

2013-01-01

The phylum Bacteroidetes is large and diverse, with rapid gliding motility and the ability to digest macromolecules associated with many genera and species. Recently, a novel protein secretion system, the Por secretion system (PorSS), was identified in two members of the phylum, the gliding bacterium Flavobacterium johnsoniae and the nonmotile oral pathogen Porphyromonas gingivalis. The components of the PorSS are not similar in sequence to those of other well-studied bacterial secretion systems. The F. johnsoniae PorSS genes are a subset of the gliding motility genes, suggesting a role for the secretion system in motility. The F. johnsoniae PorSS is needed for assembly of the gliding motility apparatus and for secretion of a chitinase, and the P. gingivalis PorSS is involved in secretion of gingipain protease virulence factors. Comparative analysis of 37 genomes of members of the phylum Bacteroidetes revealed the widespread occurrence of gliding motility genes and PorSS genes. Genes associated with other bacterial protein secretion systems were less common. The results suggest that gliding motility is more common than previously reported. Microscopic observations confirmed that organisms previously described as nonmotile, including Croceibacter atlanticus, “Gramella forsetii,” Paludibacter propionicigenes, Riemerella anatipestifer, and Robiginitalea biformata, exhibit gliding motility. Three genes (gldA, gldF, and gldG) that encode an apparent ATP-binding cassette transporter required for F. johnsoniae gliding were absent from two related gliding bacteria, suggesting that the transporter may not be central to gliding motility. PMID:23123910

What is the real impairment on esophageal motility in patients with gastroesophageal reflux disease?

PubMed

Falcão, Angela; Nasi, Ary; Brandão, Jeovana; Sallum, Rubens; Cecconello, Ivan

2013-04-01

Impairment of esophageal motility is a common finding in patients with gastroesophageal reflux disease (GERD) as reduced lower esophageal sphincter (LES) basal pressure. A very low LES pressure might facilitate the occurrence of more gastroesophageal reflux whereas abnormal esophageal peristalsis may contribute to impaired esophageal clearance after reflux. Evaluate the esophageal motor function of the lower esophageal sphincter and esophageal body in the various forms of gastroesophageal reflux disease. The manometrics records of 268 patients, who had evaluation of the esophageal motility as part of the diagnostic gastroesophageal reflux disease were split into four groups, as follows: 33 patients who had no esophagitis; 92 patients who had erosive esophagitis; 101 patients who had short Barrett's esophagus and 42 patients who had long Barrett's esophagus. The group who had long Barrett's esophagus showed smaller mean LES pressure and higher percentage of marked LES hypotonia; in the distal segment of the esophageal body the this group showed higher percentage of marked hypocontractility of the distal segment (<30 mm Hg); this same group showed higher percentage of esophageal motility disorders. The most intense esophageal motility disorders and lower pressure of lower esophageal sphincter were noted in the group with long Barrett's esophagus. Those with reflux esophagitis and short Barrett's esophagus had esophageal motility impairment, intermediate among patients with esophagitis and long Barrett's esophagus. Patients with typical symptoms of gastroesophageal reflux but without esophagitis by endoscopy study showed no impairment of esophageal motility.

Genetic Analysis of Collective Motility of Paenibacillus sp. NAIST15-1

PubMed Central

Kobayashi, Kazuo; Kanesaki, Yu

2016-01-01

Bacteria have developed various motility mechanisms to adapt to a variety of solid surfaces. A rhizosphere isolate, Paenibacillus sp. NAIST15-1, exhibited unusual motility behavior. When spotted onto 1.5% agar media, Paenibacillus sp. formed many colonies, each of which moved around actively at a speed of 3.6 μm/sec. As their density increased, each moving colony began to spiral, finally forming a static round colony. Despite its unusual motility behavior, draft genome sequencing revealed that both the composition and organization of flagellar genes in Paenibacillus sp. were very similar to those in Bacillus subtilis. Disruption of flagellar genes and flagellar stator operons resulted in loss of motility. Paenibacillus sp. showed increased transcription of flagellar genes and hyperflagellation on hard agar media. Thus, increased flagella and their rotation drive Paenibacillus sp. motility. We also identified a large extracellular protein, CmoA, which is conserved only in several Paenibacillus and related species. A cmoA mutant could neither form moving colonies nor move on hard agar media; however, motility was restored by exogenous CmoA. CmoA was located around cells and enveloped cell clusters. Comparison of cellular behavior between the wild type and cmoA mutant indicated that extracellular CmoA is involved in drawing water out of agar media and/or smoothing the cell surface interface. This function of CmoA probably enables Paenibacillus sp. to move on hard agar media. PMID:27764113

Left-right asymmetry: cilia stir up new surprises in the node.

PubMed

Babu, Deepak; Roy, Sudipto

2013-05-29

Cilia are microtubule-based hair-like organelles that project from the surface of most eukaryotic cells. They play critical roles in cellular motility, fluid transport and a variety of signal transduction pathways. While we have a good appreciation of the mechanisms of ciliary biogenesis and the details of their structure, many of their functions demand a more lucid understanding. One such function, which remains as intriguing as the time when it was first discovered, is how beating cilia in the node drive the establishment of left-right asymmetry in the vertebrate embryo. The bone of contention has been the two schools of thought that have been put forth to explain this phenomenon. While the 'morphogen hypothesis' believes that ciliary motility is responsible for the transport of a morphogen preferentially to the left side, the 'two-cilia model' posits that the motile cilia generate a leftward-directed fluid flow that is somehow sensed by the immotile sensory cilia on the periphery of the node. Recent studies with the mouse embryo argue in favour of the latter scenario. Yet this principle may not be generally conserved in other vertebrates that use nodal flow to specify their left-right axis. Work with the teleost fish medaka raises the tantalizing possibility that motility as well as sensory functions of the nodal cilia could be residing within the same organelle. In the end, how ciliary signalling is transmitted to institute asymmetric gene expression that ultimately induces asymmetric organogenesis remains unresolved.

Left–right asymmetry: cilia stir up new surprises in the node

PubMed Central

Babu, Deepak; Roy, Sudipto

2013-01-01

Cilia are microtubule-based hair-like organelles that project from the surface of most eukaryotic cells. They play critical roles in cellular motility, fluid transport and a variety of signal transduction pathways. While we have a good appreciation of the mechanisms of ciliary biogenesis and the details of their structure, many of their functions demand a more lucid understanding. One such function, which remains as intriguing as the time when it was first discovered, is how beating cilia in the node drive the establishment of left–right asymmetry in the vertebrate embryo. The bone of contention has been the two schools of thought that have been put forth to explain this phenomenon. While the ‘morphogen hypothesis’ believes that ciliary motility is responsible for the transport of a morphogen preferentially to the left side, the ‘two-cilia model’ posits that the motile cilia generate a leftward-directed fluid flow that is somehow sensed by the immotile sensory cilia on the periphery of the node. Recent studies with the mouse embryo argue in favour of the latter scenario. Yet this principle may not be generally conserved in other vertebrates that use nodal flow to specify their left–right axis. Work with the teleost fish medaka raises the tantalizing possibility that motility as well as sensory functions of the nodal cilia could be residing within the same organelle. In the end, how ciliary signalling is transmitted to institute asymmetric gene expression that ultimately induces asymmetric organogenesis remains unresolved. PMID:23720541

Neurokinin NK1 and NK3 receptors as targets for drugs to treat gastrointestinal motility disorders and pain.

PubMed

Sanger, Gareth J

2004-04-01

NK1 and NK3 receptors do not appear to play significant roles in normal GI functions, but both may be involved in defensive or pathological processes. NK1 receptor antagonists are antiemetic, operating via vagal sensory and motor systems, so there is a need to study their effects on other gastro-vagal functions thought to play roles in functional bowel disorders. Interactions between NK1 receptors and enteric nonadrenergic, noncholinergic motorneurones suggest a need to explore the role of this receptor in disrupted colonic motility. NK1 receptor antagonism does not exert consistent analgesic activity in humans, but similar studies have not been carried out against pain of GI origin, where NK1 receptors may have additional influences on mucosal inflammatory or "irritant" processes. NK3 receptors mediate certain disruptions of intestinal motility. The activity may be driven by tachykinins released from intrinsic primary afferent neurones (IPANs), which induce slow EPSP activity in connecting IPANs and hence, a degree of hypersensitivity within the enteric nervous system. The same process is also proposed to increase C-fibre sensitivity, either indirectly or directly. Thus, NK3 receptor antagonists inhibit intestinal nociception via a "peripheral" mechanism that may be intestine-specific. Studies with talnetant and other selective NK3 receptor antagonists are, therefore, revealing an exciting and novel pathway by which pathological changes in intestinal motility and nociception can be induced, suggesting a role for NK3 receptor antagonism in irritable bowel syndrome.

[Qilin Pills for idiopathic oligoasthenospermia: A multi-centered randomized double-blind controlled clinical trial].

PubMed

Mao, Jia-Ming; Jiang, Hui; Wang, Chuan-Hang; Ning, Ke-Qin; Liu, Ji-Hong; Yang, Shu-Wen; Li, Hai-Song; Zhou, Shao-Hu; Zhang, Zhi-Chao; Xu, Ji-Xiu; Huang, Yong-Han

2017-03-01

To evaluate the clinical efficacy and safety of Qilin Pills in the treatment of oligoasthenospermia in infertile men. This multi-centered randomized double-blind controlled clinical trial included 216 infertile males with oligoasthenospermia, 108 in the trial group and the other 108 in the control, the former treated with Qilin Pills at the dose of 6 g tid while the latter with Wuziyanzong Pills at 6 g bid, both for 12 weeks. We examined the total sperm count, sperm motility and the count of progressively motile sperm of the patients before and at 4, 8 and 12 weeks after medication and evaluated the safety of the drug based on the adverse events and the laboratory results of blood and urine routine examinations and liver and kidney function tests. Compared with the baseline, the patients in the trial group showed a significant time-dependent improvement after 4, 8 and 12 weeks of medication in sperm motility (21.75% vs 27.54%, 29.04% and 32.95%, P <0.05), total sperm count (156.27 ×106 vs 177.33, 188.18 and 205.44 ×106, P <0.05), and the count of progressively motile sperm (32.08 ×10⁶/ml vs 46.33, 50.98 and 61.10 ×10⁶/ml, P <0.05). The three parameters above were also improved in the controls, but more significantly in the trial group (P <0.05). Qilin Pills can evidently improve the semen quality of oligoasthenospermia patients with no obvious adverse events.

Curcumin as a potential non-steroidal contraceptive with spermicidal and microbicidal properties.

PubMed

Naz, R K; Lough, M L

2014-05-01

Curcumin, a component of the curry powder turmeric, has immense biological properties, including anticancer effects. The objective of this study was to determine if curcumin can provide a novel non-steroidal contraceptive having both spermicidal and microbicidal properties. The effect of curcumin, with and without photosensitization, was examined on human sperm forward motility and growth of several aerobic (n=8) and anaerobic bacteria (n=4) and yeast (n=7) strains implicated in vaginosis, vaginitis, and vaginal infections in women. The effect of various concentrations of curcumin on human sperm and microbes (aerobic and anaerobic bacteria and yeast) was tested. The effect on sperm was examined by counting the sperm forward motility, and on microbes by agar and broth dilutions and colony counting. Each experiment was repeated using different semen specimens, and bacteria and yeast stocks. Curcumin caused a concentration-dependent inhibition of sperm forward motility with a total block at ≥250μM concentration. After photosensitization, the effective concentration to completely block sperm forward motility decreased 25-fold, now requiring only 10μM concentration for total inhibition. Curcumin concentrations between 100 and 500μM completely blocked the growth of all the bacteria and yeast strains tested. After photosensitization, the effective concentration to completely inhibit microbial growth decreased 10-fold for aerobic bacteria and yeast, and 5-fold for anaerobic bacteria. These findings suggest that curcumin can block sperm function and bacteria/yeast growth. It can potentially provide an ideal non-steroidal contraceptive having both spermicidal and microbicidal properties against vaginal infections. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A transposon mutant library of Bacillus cereus ATCC 10987 reveals novel genes required for biofilm formation and implicates motility as an important factor for pellicle-biofilm formation.

PubMed

Okshevsky, Mira; Louw, Matilde Greve; Lamela, Elena Otero; Nilsson, Martin; Tolker-Nielsen, Tim; Meyer, Rikke Louise

2018-04-01

Bacillus cereus is one of the most common opportunistic pathogens causing foodborne illness, as well as a common source of contamination in the dairy industry. B. cereus can form robust biofilms on food processing surfaces, resulting in food contamination due to shedding of cells and spores. Despite the medical and industrial relevance of this species, the genetic basis of biofilm formation in B. cereus is not well studied. In order to identify genes required for biofilm formation in this bacterium, we created a library of 5000 +  transposon mutants of the biofilm-forming strain B. cereusATCC 10987, using an unbiased mariner transposon approach. The mutant library was screened for the ability to form a pellicle biofilm at the air-media interface, as well as a submerged biofilm at the solid-media interface. A total of 91 genes were identified as essential for biofilm formation. These genes encode functions such as chemotaxis, amino acid metabolism and cellular repair mechanisms, and include numerous genes not previously known to be required for biofilm formation. Although the majority of disrupted genes are not directly responsible for motility, further investigations revealed that the vast majority of the biofilm-deficient mutants were also motility impaired. This observation implicates motility as a pivotal factor in the formation of a biofilm by B. cereus. These results expand our knowledge of the fundamental molecular mechanisms of biofilm formation by B. cereus. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Mice lacking the USP2 deubiquitinating enzyme have severe male subfertility associated with defects in fertilization and sperm motility.

PubMed

Bedard, Nathalie; Yang, Yaoming; Gregory, Mary; Cyr, Daniel G; Suzuki, João; Yu, Xiaomin; Chian, Ri-Cheng; Hermo, Louis; O'Flaherty, Cristian; Smith, Charles E; Clarke, Hugh J; Wing, Simon S

2011-09-01

The ubiquitin-proteasome system plays an important role in spermatogenesis. However, the functions of deubiquitinating enzymes in this process remain poorly characterized. We previously showed that the deubiquitinating enzyme USP2 is induced in late elongating spermatids. To identify its function, we generated mice lacking USP2. Usp2 -/- mice appeared normal, and the weights of major organs, including the testis, did not differ from wild type (Usp2 +/+). However, although the numbers of testicular spermatids and epididymal spermatozoa were normal in Usp2 -/- males, these animals had a severe defect in fertility, yielding only 12% as many offspring as Usp2 +/+ littermates. Spermatogenesis in Usp2 -/- mice was morphologically normal except for the presence of abnormal aggregations of elongating spermatids and formation of multinucleated cells in some tubules. The epididymal epithelium was morphologically normal in Usp2 -/- mice, but some abnormal cells other than sperm were present in the lumen. Usp2 -/- epididymal spermatozoa manifested normal motility when incubated in culture media, but rapidly became immotile when incubated in PBS in contrast to Usp2 +/+ spermatozoa, which largely maintained motility under this condition. Usp2 -/- and +/+ spermatozoa underwent acrosome reactions in vitro with similar frequency. In vitro fertilization assays demonstrated a severe defect in the ability of Usp2 -/- spermatozoa to fertilize eggs. This could be bypassed by intracytoplasmic sperm injection or removal of the zona pellucida, which resulted in fertilization rates similar to that of Usp2 +/+ mice. We demonstrate for the first time, using mouse transgenic approaches, a role for the ubiquitin system in fertilization.

New-generation 5-HT4 receptor agonists: potential for treatment of gastrointestinal motility disorders.

PubMed

Manabe, Noriaki; Wong, Banny S; Camilleri, Michael

2010-06-01

Gastrointestinal (GI) dysmotility is an important mechanism in functional GI disorders (FGIDs) including constipation, irritable bowel syndrome, functional dyspepsia, and gastroparesis. 5-hydroxytryptamine(4) (5-HT(4)) receptors are targets for the treatment of GI motility disorders. However, older 5-HT(4) receptor agonists had limited clinical success because they were associated with changes in the function of the cardiac HERG potassium channel. We conducted a PubMed search using the following key words alone or in combination: 5-HT(4), safety, toxicity, pharmacokinetics, pharmacodynamics, clinical trial, cardiac, hERG, arrhythmia, potassium current, elderly, prucalopride, ATI-7505, and velusetrag (TD-5108), to review mechanisms of action, clinical efficacy, safety and tolerability of three new-generation 5-HT(4) receptor agonists. Prucalopride, ATI-7505, and velusetrag (TD-5108) are highly selective, high-affinity 5-HT(4) receptor agonists that are devoid of action on other receptors within their therapeutic range. Their efficacy has been demonstrated in pharmacodynamic studies which demonstrate acceleration of colonic transit and, to a variable degree, in clinical trials that significantly relieve chronic constipation. Currently available evidence shows that the new 5-HT(4) receptor agonists have safe cardiac profiles. New-generation 5-HT(4) receptor agonists and future drugs targeting organ-specific splice variants are promising approaches to treat GI dysmotility, particularly colonic diseases.

Automated tracking of tumor-stroma morphology in microtissues identifies functional targets within the tumor microenvironment for therapeutic intervention

PubMed Central

Åkerfelt, Malin; Bayramoglu, Neslihan; Robinson, Sean; Toriseva, Mervi; Schukov, Hannu-Pekka; Härmä, Ville; Virtanen, Johannes; Sormunen, Raija; Kaakinen, Mika; Kannala, Juho; Eklund, Lauri; Heikkilä, Janne; Nees, Matthias

2015-01-01

Cancer-associated fibroblasts (CAFs) constitute an important part of the tumor microenvironment and promote invasion via paracrine functions and physical impact on the tumor. Although the importance of including CAFs into three-dimensional (3D) cell cultures has been acknowledged, computational support for quantitative live-cell measurements of complex cell cultures has been lacking. Here, we have developed a novel automated pipeline to model tumor-stroma interplay, track motility and quantify morphological changes of 3D co-cultures, in real-time live-cell settings. The platform consists of microtissues from prostate cancer cells, combined with CAFs in extracellular matrix that allows biochemical perturbation. Tracking of fibroblast dynamics revealed that CAFs guided the way for tumor cells to invade and increased the growth and invasiveness of tumor organoids. We utilized the platform to determine the efficacy of inhibitors in prostate cancer and the associated tumor microenvironment as a functional unit. Interestingly, certain inhibitors selectively disrupted tumor-CAF interactions, e.g. focal adhesion kinase (FAK) inhibitors specifically blocked tumor growth and invasion concurrently with fibroblast spreading and motility. This complex phenotype was not detected in other standard in vitro models. These results highlight the advantage of our approach, which recapitulates tumor histology and can significantly improve cancer target validation in vitro. PMID:26375443

Therapeutic perspectives for melatonin agonists and antagonists.

PubMed

Delagrange, P; Atkinson, J; Boutin, J A; Casteilla, L; Lesieur, D; Misslin, R; Pellissier, S; Pénicaud, L; Renard, P

2003-04-01

Melatonin is a neurohormone synthesized in the pineal gland during the dark period in all species, including humans. The diversity and differences in melatonin receptor distribution in the brain and extracerebral organs suggest multiple functional roles for melatonin. Administration of melatonin agonists reduces neophobia and treatment with a melatonin antagonist during the dark period reverses the anxiolytic-like effect of endogenous melatonin. Chronic treatment with agonists prevents various perturbations induced by chronic mild stress. Melatonin in vivo directly constricts cerebral arterioles in rats and decreases the lower limit of cerebral blood flow autoregulation, suggesting that melatonin may diminish the risk of hypoperfusion-induced cerebral ischemia. At the extracerebral level, melatonin regulates intestinal motility in rats. The intestinal postprandial motor response is shorter in the dark phase than in the light phase and this reduction is reversed in animals pretreated with a melatonin antagonist. Moreover, melatonin reduces the duration of cholecystokinin excitomotor effect. Endogenous melatonin may modulate intestinal motility to coordinate intestinal functions such as digestion and transit and control the metabolism of the animal. An adipocyte melatonin binding site may also participate in this control. Melatonin is involved in a wide range of physiological functions. The question remains as to whether evolution, adaptation and diurnal life have modified the physiological role of melatonin in humans. Moreover, the functional role of each of the receptor subtypes has to be characterized to design selective ligands to treat specific diseases.

The Pseudomonas aeruginosa ribbon-helix-helix DNA-binding protein AlgZ (AmrZ) controls twitching motility and biogenesis of type IV pili.

PubMed

Baynham, Patricia J; Ramsey, Deborah M; Gvozdyev, Borys V; Cordonnier, Ellen M; Wozniak, Daniel J

2006-01-01

Pseudomonas aeruginosa is an opportunistic pathogen that is commonly found in water and soil. In order to colonize surfaces with low water content, P. aeruginosa utilizes a flagellum-independent form of locomotion called twitching motility, which is dependent upon the extension and retraction of type IV pili. This study demonstrates that AlgZ, previously identified as a DNA-binding protein absolutely required for transcription of the alginate biosynthetic operon, is required for twitching motility. AlgZ may be required for the biogenesis or function of type IV pili in twitching motility. Transmission electron microscopy analysis of an algZ deletion in nonmucoid PAO1 failed to detect surface pili. To examine expression and localization of PilA (the major pilin subunit), whole-cell extracts and cell surface pilin preparations were analyzed by Western blotting. While the PilA levels present in whole-cell extracts were similar for wild-type P. aeruginosa and P. aeruginosa with the algZ deletion, the amount of PilA on the surface of the cells was drastically reduced in the algZ mutant. Analysis of algZ and algD mutants indicates that the DNA-binding activity of AlgZ is essential for the regulation of twitching motility and that this is independent of the role of AlgZ in alginate expression. These data show that AlgZ DNA-binding activity is required for twitching motility independently of its role in alginate production and that this involves the surface localization of type IV pili. Given this new role in twitching motility, we propose that algZ (PA3385) be designated amrZ (alginate and motility regulator Z).

Trajectories of Listeria-type motility in two dimensions

NASA Astrophysics Data System (ADS)

Wen, Fu-Lai; Leung, Kwan-tai; Chen, Hsuan-Yi

2012-12-01

Force generated by actin polymerization is essential in cell motility and the locomotion of organelles or bacteria such as Listeria monocytogenes. Both in vivo and in vitro experiments on actin-based motility have observed geometrical trajectories including straight lines, circles, S-shaped curves, and translating figure eights. This paper reports a phenomenological model of an actin-propelled disk in two dimensions that generates geometrical trajectories. Our model shows that when the evolutions of actin density and force per filament on the disk are strongly coupled to the disk self-rotation, it is possible for a straight trajectory to lose its stability. When the instability is due to a pitchfork bifurcation, the resulting trajectory is a circle; a straight trajectory can also lose stability through a Hopf bifurcation, and the resulting trajectory is an S-shaped curve. We also show that a half-coated disk, which mimics the distribution of functionalized proteins in Listeria, also undergoes similar symmetry-breaking bifurcations when the straight trajectory loses stability. For both a fully coated disk and a half-coated disk, when the trajectory is an S-shaped curve, the angular frequency of the disk self-rotation is different from that of the disk trajectory. However, for circular trajectories, these angular frequencies are different for a fully coated disk but the same for a half-coated disk.

Motility-Driven Glass and Jamming Transitions in Biological Tissues

NASA Astrophysics Data System (ADS)

Bi, Dapeng; Yang, Xingbo; Marchetti, M. Cristina; Manning, M. Lisa

2016-04-01

Cell motion inside dense tissues governs many biological processes, including embryonic development and cancer metastasis, and recent experiments suggest that these tissues exhibit collective glassy behavior. To make quantitative predictions about glass transitions in tissues, we study a self-propelled Voronoi model that simultaneously captures polarized cell motility and multibody cell-cell interactions in a confluent tissue, where there are no gaps between cells. We demonstrate that the model exhibits a jamming transition from a solidlike state to a fluidlike state that is controlled by three parameters: the single-cell motile speed, the persistence time of single-cell tracks, and a target shape index that characterizes the competition between cell-cell adhesion and cortical tension. In contrast to traditional particulate glasses, we are able to identify an experimentally accessible structural order parameter that specifies the entire jamming surface as a function of model parameters. We demonstrate that a continuum soft glassy rheology model precisely captures this transition in the limit of small persistence times and explain how it fails in the limit of large persistence times. These results provide a framework for understanding the collective solid-to-liquid transitions that have been observed in embryonic development and cancer progression, which may be associated with epithelial-to-mesenchymal transition in these tissues.

The Wireless Motility Capsule: a One-Stop Shop for the Evaluation of GI Motility Disorders.

PubMed

Saad, Richard J

2016-03-01

The wireless motility and pH capsule (WMC) provides an office-based test to simultaneously assess both regional and whole gut transit. Ingestion of this non-digestible capsule capable of measuring temperature, pH, and the pressure of its immediate surroundings allows for the measurement of gastric, small bowel, and colonic transit times in an ambulatory setting. Approved by the US Food and Drug Administration for the evaluation of suspected conditions of delayed gastric emptying and the evaluation of colonic transit in chronic idiopathic constipation, WMC should be considered in suspected gastrointestinal motility disorders as it provides a single study capable of simultaneously assessing for regional, multiregional, or generalized motility disorders. Specific indications for testing with the WMC should include the evaluation of suspect cases of gastroparesis, small bowel dysmotility, and slow transit constipation, as well as symptom syndromes suggestive of a multiregional or generalized gastrointestinal transit delay.

Polymorphonuclear cell motility, ankylosing spondylitis, and HLA B27.

PubMed Central

Pease, C T; Fordham, J N; Currey, H L

1984-01-01

Polymorphonuclear leucocyte (PMN) function was studied in 29 subjects with ankylosing spondylitis (AS). Of these, 20 were HLA B27+ve and 9 B27-ve. There were 30 controls and, of these, 15 were B27+ve. Random and directed cell migration was measured by 2 techniques: migration through a micropore filter and migration under an agar film. The chemo-attractant was either case in-activated serum or zymosan-activated serum. By both techniques directed motility was increased in subjects with B27 or with AS when compared to the B27-ve controls. This suggests that the disease AS and the possession of B27 are both associated with increased PMN motility. PMID:6608924

Leishmania infection inhibits macrophage motility by altering F-actin dynamics and the expression of adhesion complex proteins.

PubMed

de Menezes, Juliana Perrone Bezerra; Koushik, Amrita; Das, Satarupa; Guven, Can; Siegel, Ariel; Laranjeira-Silva, Maria Fernanda; Losert, Wolfgang; Andrews, Norma W

2017-03-01

Leishmania is an intracellular protozoan parasite that causes a broad spectrum of clinical manifestations, ranging from self-healing skin lesions to fatal visceralizing disease. As the host cells of choice for all species of Leishmania, macrophages are critical for the establishment of infections. How macrophages contribute to parasite homing to specific tissues and how parasites modulate macrophage function are still poorly understood. In this study, we show that Leishmania amazonensis infection inhibits macrophage roaming motility. The reduction in macrophage speed is not dependent on particle load or on factors released by infected macrophages. L. amazonensis-infected macrophages also show reduced directional migration in response to the chemokine MCP-1. We found that infected macrophages have lower levels of total paxillin, phosphorylated paxillin, and phosphorylated focal adhesion kinase when compared to noninfected macrophages, indicating abnormalities in the formation of signaling adhesion complexes that regulate motility. Analysis of the dynamics of actin polymerization at peripheral sites also revealed a markedly enhanced F-actin turnover frequency in L. amazonensis-infected macrophages. Thus, Leishmania infection inhibits macrophage motility by altering actin dynamics and impairing the expression of proteins that function in plasma membrane-extracellular matrix interactions. © 2016 John Wiley & Sons Ltd.

PLAG1 deficiency impairs spermatogenesis and sperm motility in mice.

PubMed

Juma, Almas R; Grommen, Sylvia V H; O'Bryan, Moira K; O'Connor, Anne E; Merriner, D Jo; Hall, Nathan E; Doyle, Stephen R; Damdimopoulou, Pauliina E; Barriga, Daniel; Hart, Adam H; Van de Ven, Wim J M; De Groef, Bert

2017-07-13

Deficiency in pleomorphic adenoma gene 1 (PLAG1) leads to reduced fertility in male mice, but the mechanism by which PLAG1 contributes to reproduction is unknown. To investigate the involvement of PLAG1 in testicular function, we determined (i) the spatial distribution of PLAG1 in the testis using X-gal staining; (ii) transcriptomic consequences of PLAG1 deficiency in knock-out and heterozygous mice compared to wild-type mice using RNA-seq; and (iii) morphological and functional consequences of PLAG1 deficiency by determining testicular histology, daily sperm production and sperm motility in knock-out and wild-type mice. PLAG1 was sparsely expressed in germ cells and in Sertoli cells. Genes known to be involved in spermatogenesis were downregulated in the testes of knock-out mice, as well as Hsd17b3, which encodes a key enzyme in androgen biosynthesis. In the absence of Plag1, a number of genes involved in immune processes and epididymis-specific genes were upregulated in the testes. Finally, loss of PLAG1 resulted in significantly lowered daily sperm production, in reduced sperm motility, and in several animals, in sloughing of the germinal epithelium. Our results demonstrate that the subfertility seen in male PLAG1-deficient mice is, at least in part, the result of significantly reduced sperm output and sperm motility.

Low physiological levels of prostaglandins E2 and F2α improve human sperm functions.

PubMed

Rios, Mariana; Carreño, Daniela V; Oses, Carolina; Barrera, Nelson; Kerr, Bredford; Villalón, Manuel

2016-03-01

Prostaglandins (PGs) have been reported to be present in the seminal fluid and cervical mucus, affecting different stages of sperm maturation from spermatogenesis to the acrosome reaction. This study assessed the effects of low physiological PGE2 and PGF2α concentrations on human sperm motility and on the ability of the spermatozoa to bind to the zona pellucida (ZP). Human spermatozoa were isolated from seminal samples with normal concentration and motility parameters and incubated with 1μM PGE2, 1μM PGF2α or control solution to determine sperm motility and the ability to bind to human ZP. The effects of both PGs on intracellular calcium levels were determined. Incubation for 2 or 18h with PGE2 or PGF2α resulted in a significant (P<0.05) increase in the percentage of spermatozoa with progressive motility. In contrast with PGF2α, PGE2 alone induced an increase in sperm intracellular calcium levels; however, the percentage of sperm bound to the human ZP was doubled for both PGs. These results indicate that incubation of human spermatozoa with low physiological levels of PGE2 or PGF2α increases sperm functions and could improve conditions for assisted reproduction protocols.

[Impact of waste landfills in the Saratov region on the sanitary condition of the soil].

PubMed

Eremin, V N; Reshetnikov, M V; Sheshnev, A S

Monitoring of environment in regions of the location of waste landfills includes the implementation of the control over a sanitary condition of soils. The main origins of the spread ofpollutants into soils are the solid particles from aerosol emissions from the functioning of landfills transmitted to surrounding territories. Within zones of the impact of three largest waste landfills in the Saratov region (Aleksandrovsky, Guselsky in the city of Saratov and Balakovsky in the city of Balakovo) there were taken 152 soil samples. According to results of the estimation in soil concentration of gross and motile forms of heavy metals of the first (Zn, Cd, Ni) and the second danger classes (Cu, Cr, Pb) there was performed the analysis of coefficients of danger- K0 and total coefficients ofpollution - Zc. There was executed the assessment of both a sanitary and hygienic condition of soils and degree of danger ofpollution. The most contrast areal features of the distribution of the danger coefficient - Ko in soils are characteristic for motile forms of heavy metals. For all three studied objects persistently there is stood out the dangerous and areal pollution of soils by association of Ni and Cu . The danger ofpollution of soils by gross forms of heavy metals is minimum. The coefficient of total pollution of Zc exceeds admissible level on motile forms of heavy metals only for the soils surrounding the Balakovo landfill. In zones of the impact of waste landfills there are located the processed lands with an adverse sanitary and hygienic condition of soils. In the region of the Guselsky object soils of the processed agricultural grounds are dangerously polluted by motile forms of Ni and Cu. In vicinities of the Balakovo waste landfill considerable areas of private gardening enterprises are dangerously polluted by the motile forms of Ni, Cu and Zn.

Hydrogen peroxide stimulates cell motile activity through LPA receptor-3 in liver epithelial WB-F344 cells.

PubMed

Shibata, Ayano; Tanabe, Eriko; Inoue, Serina; Kitayoshi, Misaho; Okimoto, Souta; Hirane, Miku; Araki, Mutsumi; Fukushima, Nobuyuki; Tsujiuchi, Toshifumi

2013-04-12

Hydrogen peroxide which is one of reactive oxygen species (ROS) mediates a variety of biological responses, including cell proliferation and migration. In the present study, we investigated whether lysophosphatidic acid (LPA) signaling is involved in cell motile activity stimulated by hydrogen peroxide. The rat liver epithelial WB-F344 cells were treated with hydrogen peroxide at 0.1 or 1 μM for 48 h. In cell motility assays, hydrogen peroxide treated cells showed significantly high cell motile activity, compared with untreated cells. To measure the expression levels of LPA receptor genes, quantitative real time RT-PCR analysis was performed. The expressions of LPA receptor-3 (Lpar3) in hydrogen peroxide treated cells were significantly higher than those in control cells, but not Lpar1 and Lpar2 genes. Next, to assess the effect of LPA3 on cell motile activity, the Lpar3 knockdown cells from WB-F344 cells were also treated with hydrogen peroxide. The cell motile activity of the knockdown cells was not stimulated by hydrogen peroxide. Moreover, in liver cancer cells, hydrogen peroxide significantly activated cell motility of Lpar3-expressing cells, but not Lpar3-unexpressing cells. These results suggest that LPA signaling via LPA3 may be mainly involved in cell motile activity of WB-F344 cells stimulated by hydrogen peroxide. Copyright © 2013 Elsevier Inc. All rights reserved.

Sperm DNA damage or progressive motility: which one is the better predictor of fertilization in vitro?

PubMed

Simon, Luke; Lewis, Sheena E M

2011-06-01

Sperm progressive motility has been reported to be one of the key factors influencing in vitro fertilization rates. However, recent studies have shown that sperm DNA fragmentation is a more robust predictor of assisted reproductive outcomes including reduced fertilization rates, embryo quality, and pregnancy rates. This study aimed to compare the usefulness of sperm progressive motility and DNA damage as predictive tools of in vitro fertilization rates. Here, 136 couples provided 1,767 eggs with an overall fertilization rate of 64.2%. The fertilization rate in vitro correlated with both sperm progressive motility (r² = 0.236; P = 0.002) and DNA fragmentation (r² = -0.318; P < 0.001). The relative risk of a poor fertilization rate was 9.5 times higher in sperm of men with high DNA fragmentation (>40%) compared with 2.6 times in sperm with poor motility (<40%). Further, sperm DNA fragmentation gave a higher specificity (93.3%) in predicting the fertilization rate than progressive motility (77.8%). Finally, the odds ratio to determine fertilization rate (>70%) was 4.81 (1.89-12.65) using progressive motility compared with 24.18 (5.21-154.51) using DNA fragmentation. This study shows that fertilization rates are directly dependent upon both sperm progressive motility and DNA fragmentation, but sperm DNA fragmentation is a much stronger test.

Hydrogen peroxide stimulates cell motile activity through LPA receptor-3 in liver epithelial WB-F344 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shibata, Ayano; Tanabe, Eriko; Inoue, Serina

2013-04-12

Highlights: •Hydrogen peroxide stimulates cell motility of WB-F344 cells. •LPA{sub 3} is induced by hydrogen peroxide in WB-F344 cells. •Cell motility by hydrogen peroxide is inhibited in LPA{sub 3} knockdown cells. •LPA signaling is involved in cell migration by hydrogen peroxide. -- Abstract: Hydrogen peroxide which is one of reactive oxygen species (ROS) mediates a variety of biological responses, including cell proliferation and migration. In the present study, we investigated whether lysophosphatidic acid (LPA) signaling is involved in cell motile activity stimulated by hydrogen peroxide. The rat liver epithelial WB-F344 cells were treated with hydrogen peroxide at 0.1 or 1more » μM for 48 h. In cell motility assays, hydrogen peroxide treated cells showed significantly high cell motile activity, compared with untreated cells. To measure the expression levels of LPA receptor genes, quantitative real time RT-PCR analysis was performed. The expressions of LPA receptor-3 (Lpar3) in hydrogen peroxide treated cells were significantly higher than those in control cells, but not Lpar1 and Lpar2 genes. Next, to assess the effect of LPA{sub 3} on cell motile activity, the Lpar3 knockdown cells from WB-F344 cells were also treated with hydrogen peroxide. The cell motile activity of the knockdown cells was not stimulated by hydrogen peroxide. Moreover, in liver cancer cells, hydrogen peroxide significantly activated cell motility of Lpar3-expressing cells, but not Lpar3-unexpressing cells. These results suggest that LPA signaling via LPA{sub 3} may be mainly involved in cell motile activity of WB-F344 cells stimulated by hydrogen peroxide.« less

Electroacupuncture at LI11 promotes jejunal motility via the parasympathetic pathway.

PubMed

Hu, Xuanming; Yuan, Mengqian; Yin, Yin; Wang, Yidan; Li, Yuqin; Zhang, Na; Sun, Xueyi; Yu, Zhi; Xu, Bin

2017-06-21

Gastrointestinal motility disorder has been demonstrated to be regulated by acupuncture treatment. The mechanisms underlying the effects of acupuncture stimulation of abdominal and lower limb acupoints on gastrointestinal motility have been thoroughly studied; however, the physiology underlying the effects of acupuncture on the forelimbs to mediate gastrointestinal motility requires further exploration. The aim of this study was to determine whether electroacupuncture (EA) at LI11 promotes jejunal motility, whether the parasympathetic pathway participates in this effect, and if so, which somatic afferent nerve fibres are involved. A manometric balloon was used to observe jejunal motility. The effects and mechanisms of EA at LI11 were explored in male Sprague-Dawley rats with or without drug administration (propranolol, clenbuterol, acetylcholine, and atropine) and with or without vagotomy. Three types of male mice (β 1 β 2 receptor-knockout [β 1 β 2 -/- ] mice, M 2 M 3 receptor-knockout [M 2 M 3 -/- ] mice and wild-type [WT] mice) were also studied by using different EA intensities (1, 2, 4, 6, and 8 mA). A total of 72 rats and 56 mice were included in the study. EA at LI11 increased the contractile amplitude of jejunal motility in the majority of both rats and mice. However, EA at LI11 did not enhance jejunal motility in rats administered atropine, rats that underwent vagotomy, and M 2 M 3 -‍‍/- mice (at all intensities). In WT mice, EA at LI11 significantly increased jejunal motility at all intensities except 1 mA, and a plateau was reached at intensities greater than 4 mA. Our results suggest that EA at LI11 promotes jejunal motility primarily by exciting the parasympathetic pathway, and that Aδ-fibres and C-fibres may play important roles in the process.

Borrelia burgdorferi CheY2 Is Dispensable for Chemotaxis or Motility but Crucial for the Infectious Life Cycle of the Spirochete.

PubMed

Xu, Hui; Sultan, Syed; Yerke, Aaron; Moon, Ki Hwan; Wooten, R Mark; Motaleb, M A

2017-01-01

The requirements for bacterial chemotaxis and motility range from dispensable to crucial for host colonization. Even though more than 50% of all sequenced prokaryotic genomes possess at least one chemotaxis signaling system, many of those genomes contain multiple copies of a chemotaxis gene. However, the functions of most of those additional genes are unknown. Most motile bacteria possess at least one CheY response regulator that is typically dedicated to the control of motility and which is usually essential for virulence. Borrelia burgdorferi appears to be notably different, in that it has three cheY genes, and our current studies on cheY2 suggests that it has varied effects on different aspects of the natural infection cycle. Mutants deficient in this protein exhibit normal motility and chemotaxis in vitro but show reduced virulence in mice. Specifically, the cheY2 mutants were severely attenuated in murine infection and dissemination to distant tissues after needle inoculation. Moreover, while ΔcheY2 spirochetes are able to survive normally in the Ixodes ticks, mice fed upon by the ΔcheY2-infected ticks did not develop a persistent infection in the murine host. Our data suggest that CheY2, despite resembling a typical response regulator, functions distinctively from most other chemotaxis CheY proteins. We propose that CheY2 serves as a regulator for a B. burgdorferi virulence determinant that is required for productive infection within vertebrate, but not tick, hosts. Copyright © 2016 American Society for Microbiology.

Borrelia burgdorferi CheY2 Is Dispensable for Chemotaxis or Motility but Crucial for the Infectious Life Cycle of the Spirochete

PubMed Central

Xu, Hui; Sultan, Syed; Yerke, Aaron; Moon, Ki Hwan; Wooten, R. Mark

2016-01-01

ABSTRACT The requirements for bacterial chemotaxis and motility range from dispensable to crucial for host colonization. Even though more than 50% of all sequenced prokaryotic genomes possess at least one chemotaxis signaling system, many of those genomes contain multiple copies of a chemotaxis gene. However, the functions of most of those additional genes are unknown. Most motile bacteria possess at least one CheY response regulator that is typically dedicated to the control of motility and which is usually essential for virulence. Borrelia burgdorferi appears to be notably different, in that it has three cheY genes, and our current studies on cheY2 suggests that it has varied effects on different aspects of the natural infection cycle. Mutants deficient in this protein exhibit normal motility and chemotaxis in vitro but show reduced virulence in mice. Specifically, the cheY2 mutants were severely attenuated in murine infection and dissemination to distant tissues after needle inoculation. Moreover, while ΔcheY2 spirochetes are able to survive normally in the Ixodes ticks, mice fed upon by the ΔcheY2-infected ticks did not develop a persistent infection in the murine host. Our data suggest that CheY2, despite resembling a typical response regulator, functions distinctively from most other chemotaxis CheY proteins. We propose that CheY2 serves as a regulator for a B. burgdorferi virulence determinant that is required for productive infection within vertebrate, but not tick, hosts. PMID:27799336

Effects of multiple collections on spermatozoa quality of Persian sturgeon, Acipenser persicus: motility, density and seminal plasma composition.

PubMed

Aramli, M S; Kalbassi, M R; Gharibi, M R

2015-02-01

In this study, we investigated the effects of multiple collections of sperm on the endangered Persian sturgeon, Acipenser persicus, in terms of a number of sperm functional parameters (percentage of motile spermatozoa, total time period of motility and sperm concentration) as well as on the ionic composition, protein concentration and osmolality of seminal plasma. Semen samples were collected from 12 induced male fish in three experimental groups that had been injected intramuscularly with LHRH-A2, at dosages of 5 μg/kg body weight, at a number of time regimes: at 12 h, 17 h and 24 h after spawning induction (1); at 24, 29 and 34 h after spawning induction (2); and at 36, 41 and 46 h after spawning induction (3). The percentage of motile spermatozoa and the period of sperm motility decreased significantly (p < 0.05) after the second and third collections. The concentration of spermatozoa decreased after the third collection, but this decline was not significant. No significant effect of multiple collections on protein concentration and ionic content (with exception of the Cl(-) ion) of seminal plasma was observed. In all experimental groups, a moderate impact of sequential collection on the osmolality (p < 0.05) of seminal plasma was observed. This study provides new data on the effects of multiple collections on spermatological characteristics in the Persian sturgeon. Our results confirm that sequential stripping after the third collections has a negative effect on a number of functional parameters associated with sperm. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Ionic imbalance, in addition to molecular crowding, abates cytoskeletal dynamics and vesicle motility during hypertonic stress

PubMed Central

Nunes, Paula; Roth, Isabelle; Meda, Paolo; Féraille, Eric; Brown, Dennis; Hasler, Udo

2015-01-01

Cell volume homeostasis is vital for the maintenance of optimal protein density and cellular function. Numerous mammalian cell types are routinely exposed to acute hypertonic challenge and shrink. Molecular crowding modifies biochemical reaction rates and decreases macromolecule diffusion. Cell volume is restored rapidly by ion influx but at the expense of elevated intracellular sodium and chloride levels that persist long after challenge. Although recent studies have highlighted the role of molecular crowding on the effects of hypertonicity, the effects of ionic imbalance on cellular trafficking dynamics in living cells are largely unexplored. By tracking distinct fluorescently labeled endosome/vesicle populations by live-cell imaging, we show that vesicle motility is reduced dramatically in a variety of cell types at the onset of hypertonic challenge. Live-cell imaging of actin and tubulin revealed similar arrested microfilament motility upon challenge. Vesicle motility recovered long after cell volume, a process that required functional regulatory volume increase and was accelerated by a return of extracellular osmolality to isosmotic levels. This delay suggests that, although volume-induced molecular crowding contributes to trafficking defects, it alone cannot explain the observed effects. Using fluorescent indicators and FRET-based probes, we found that intracellular ATP abundance and mitochondrial potential were reduced by hypertonicity and recovered after longer periods of time. Similar to the effects of osmotic challenge, isovolumetric elevation of intracellular chloride concentration by ionophores transiently decreased ATP production by mitochondria and abated microfilament and vesicle motility. These data illustrate how perturbed ionic balance, in addition to molecular crowding, affects membrane trafficking. PMID:26045497

Matriptase is required for the active form of hepatocyte growth factor induced Met, focal adhesion kinase and protein kinase B activation on neural stem/progenitor cell motility.

PubMed

Fang, Jung-Da; Lee, Sheau-Ling

2014-07-01

Hepatocyte growth factor (HGF) is a chemoattractant and inducer for neural stem/progenitor (NS/P) cell migration. Although the type II transmembrane serine protease, matriptase (MTP) is an activator of the latent HGF, MTP is indispensable on NS/P cell motility induced by the active form of HGF. This suggests that MTP's action on NS/P cell motility involves mechanisms other than proteolytic activation of HGF. In the present study, we investigate the role of MTP in HGF-stimulated signaling events. Using specific inhibitors of phosphatidylinositol-3-kinase (PI3K), protein kinase B (Akt) or focal adhesion kinase (FAK), we demonstrated that in NS/P cells HGF-activated c-Met induces PI3k-Akt signaling which then leads to FAK activation. This signaling pathway ultimately induces MMP2 expression and NS/P cell motility. Knocking down of MTP in NS/P cells with specific siRNA impaired HGF-stimulation of c-Met, Akt and FAK activation, blocked HGF-induced production of MMP2 and inhibited HGF-stimulated NS/P cell motility. MTP-knockdown NS/P cells cultured in the presence of recombinant protein of MTP protease domain or transfected with the full-length wild-type but not the protease-defected MTP restored HGF-responsive events in NS/P cells. In addition to functioning as HGF activator, our data revealed novel function of MTP on HGF-stimulated c-Met signaling activation. Copyright © 2014. Published by Elsevier B.V.

Quantifying the roles of random motility and directed motility using advection-diffusion theory for a 3T3 fibroblast cell migration assay stimulated with an electric field.

PubMed

Simpson, Matthew J; Lo, Kai-Yin; Sun, Yung-Shin

2017-03-17

Directed cell migration can be driven by a range of external stimuli, such as spatial gradients of: chemical signals (chemotaxis); adhesion sites (haptotaxis); or temperature (thermotaxis). Continuum models of cell migration typically include a diffusion term to capture the undirected component of cell motility and an advection term to capture the directed component of cell motility. However, there is no consensus in the literature about the form that the advection term takes. Some theoretical studies suggest that the advection term ought to include receptor saturation effects. However, others adopt a much simpler constant coefficient. One of the limitations of including receptor saturation effects is that it introduces several additional unknown parameters into the model. Therefore, a relevant research question is to investigate whether directed cell migration is best described by a simple constant tactic coefficient or a more complicated model incorporating saturation effects. We study directed cell migration using an experimental device in which the directed component of the cell motility is driven by a spatial gradient of electric potential, which is known as electrotaxis. The electric field (EF) is proportional to the spatial gradient of the electric potential. The spatial variation of electric potential across the experimental device varies in such a way that there are several subregions on the device in which the EF takes on different values that are approximately constant within those subregions. We use cell trajectory data to quantify the motion of 3T3 fibroblast cells at different locations on the device to examine how different values of the EF influences cell motility. The undirected (random) motility of the cells is quantified in terms of the cell diffusivity, D, and the directed motility is quantified in terms of a cell drift velocity, v. Estimates D and v are obtained under a range of four different EF conditions, which correspond to normal physiological conditions. Our results suggest that there is no anisotropy in D, and that D appears to be approximately independent of the EF and the electric potential. The drift velocity increases approximately linearly with the EF, suggesting that the simplest linear advection term, with no additional saturation parameters, provides a good explanation of these physiologically relevant data. We find that the simplest linear advection term in a continuum model of directed cell motility is sufficient to describe a range of different electrotaxis experiments for 3T3 fibroblast cells subject to normal physiological values of the electric field. This is useful information because alternative models that include saturation effects involve additional parameters that need to be estimated before a partial differential equation model can be applied to interpret or predict a cell migration experiment.

Guaifenesin and increased sperm motility: a preliminary case report.

PubMed

Means, Gary; Berry-Cabán, Cristóbal S; Hammermeuller, Kurt

2010-12-20

A review of the literature and an extensive Medline search revealed that this is the first case report of the use of guaifenesin to increase sperm motility. A 32-year-old male presented for an infertility evaluation. He reported an inability to conceive with his wife after 18 months of unprotected intercourse. A semen analysis was performed that included spermatozoa count, liquefaction, morphology, motility, viscosity and volume. Initial results of the semen analysis demonstrated low sperm count and motility. The provider offered treatment with guaifenesin 600 mg extended release tablets twice daily. Two months after guaifenesin therapy the semen analysis was repeated that demonstrated marked improvement in both total sperm count and motility. Evidence for the effectiveness of guaifenesin is almost entirely anecdotal. Given the mechanism of action of guaifenesin, it is not clear from this case why the patient demonstrated such a large improvement in both sperm count and motility. Additional studies of the effects of guaifenesin on male fertility could yield information of the medication's effect on men with normal or decreased total sperm counts.

Guaifenesin and increased sperm motility: a preliminary case report

PubMed Central

Means, Gary; Berry-Cabán, Cristóbal S; Hammermeuller, Kurt

2011-01-01

Background A review of the literature and an extensive Medline search revealed that this is the first case report of the use of guaifenesin to increase sperm motility. Case A 32-year-old male presented for an infertility evaluation. He reported an inability to conceive with his wife after 18 months of unprotected intercourse. A semen analysis was performed that included spermatozoa count, liquefaction, morphology, motility, viscosity and volume. Initial results of the semen analysis demonstrated low sperm count and motility. The provider offered treatment with guaifenesin 600 mg extended release tablets twice daily. Two months after guaifenesin therapy the semen analysis was repeated that demonstrated marked improvement in both total sperm count and motility. Conclusion Evidence for the effectiveness of guaifenesin is almost entirely anecdotal. Given the mechanism of action of guaifenesin, it is not clear from this case why the patient demonstrated such a large improvement in both sperm count and motility. Additional studies of the effects of guaifenesin on male fertility could yield information of the medication’s effect on men with normal or decreased total sperm counts. PMID:21403786

SIRT1 inhibits the mouse intestinal motility and epithelial proliferation

USDA-ARS?s Scientific Manuscript database

SIRT1 inhibits the mouse intestinal motility and epithelial proliferation. Sirtuin 1 (SIRT1), a NAD+-dependent histone deacetylase, is involved in a wide array of cellular processes, including glucose homeostasis, energy metabolism, proliferation and apoptosis, and immune response. However, it is un...

Motile cilia of human airway epithelia contain hedgehog signaling components that mediate noncanonical hedgehog signaling.

PubMed

Mao, Suifang; Shah, Alok S; Moninger, Thomas O; Ostedgaard, Lynda S; Lu, Lin; Tang, Xiao Xiao; Thornell, Ian M; Reznikov, Leah R; Ernst, Sarah E; Karp, Philip H; Tan, Ping; Keshavjee, Shaf; Abou Alaiwa, Mahmoud H; Welsh, Michael J

2018-02-06

Differentiated airway epithelia produce sonic hedgehog (SHH), which is found in the thin layer of liquid covering the airway surface. Although previous studies showed that vertebrate HH signaling requires primary cilia, as airway epithelia mature, the cells lose primary cilia and produce hundreds of motile cilia. Thus, whether airway epithelia have apical receptors for SHH has remained unknown. We discovered that motile cilia on airway epithelial cells have HH signaling proteins, including patched and smoothened. These cilia also have proteins affecting cAMP-dependent signaling, including Gα i and adenylyl cyclase 5/6. Apical SHH decreases intracellular levels of cAMP, which reduces ciliary beat frequency and pH in airway surface liquid. These results suggest that apical SHH may mediate noncanonical HH signaling through motile cilia to dampen respiratory defenses at the contact point between the environment and the lung, perhaps counterbalancing processes that stimulate airway defenses. Copyright © 2018 the Author(s). Published by PNAS.

Inhibitory effects of LPA1 on cell motile activities stimulated by hydrogen peroxide and 2,3-dimethoxy-1,4-naphthoquinone in fibroblast 3T3 cells.

PubMed

Hirane, Miku; Araki, Mutsumi; Dong, Yan; Honoki, Kanya; Fukushima, Nobuyuki; Tsujiuchi, Toshifumi

2013-11-08

Reactive oxygen species (ROS) are known to mediate a variety of biological responses, including cell motility. Recently, we indicated that lysophosphatidic acid (LPA) receptor-3 (LPA3) increased cell motile activity stimulated by hydrogen peroxide. In the present study, we assessed the role of LPA1 in the cell motile activity mediated by ROS in mouse fibroblast 3T3 cells. 3T3 cells were treated with hydrogen peroxide and 2,3-dimethoxy-1,4-naphthoquinone (DMNQ) at concentrations of 0.1 and 1 μM for 48 h. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3 cells treated with hydrogen peroxide and DMNQ were significantly higher than those of untreated cells. 3T3 cells treated with hydrogen peroxide and DMNQ showed elevated expression levels of the Lpar3 gene, but not the Lpar1 and Lpar2 genes. To investigate the effects of LPA1 on the cell motile activity induced by hydrogen peroxide and DMNQ, Lpar1-overexpressing (3T3-a1) cells were generated from 3T3 cells and treated with hydrogen peroxide and DMNQ. The cell motile activities stimulated by hydrogen peroxide and DMNQ were markedly suppressed in 3T3-a1 cells. These results suggest that LPA signaling via LPA1 inhibits the cell motile activities stimulated by hydrogen peroxide and DMNQ in 3T3 cells. Copyright © 2013 Elsevier Inc. All rights reserved.

Gliding Motility of Babesia bovis Merozoites Visualized by Time-Lapse Video Microscopy

PubMed Central

Asada, Masahito; Goto, Yasuyuki; Yahata, Kazuhide; Yokoyama, Naoaki; Kawai, Satoru; Inoue, Noboru; Kaneko, Osamu; Kawazu, Shin-ichiro

2012-01-01

Background Babesia bovis is an apicomplexan intraerythrocytic protozoan parasite that induces babesiosis in cattle after transmission by ticks. During specific stages of the apicomplexan parasite lifecycle, such as the sporozoites of Plasmodium falciparum and tachyzoites of Toxoplasma gondii, host cells are targeted for invasion using a unique, active process termed “gliding motility”. However, it is not thoroughly understood how the merozoites of B. bovis target and invade host red blood cells (RBCs), and gliding motility has so far not been observed in the parasite. Methodology/Principal Findings Gliding motility of B. bovis merozoites was revealed by time-lapse video microscopy. The recorded images revealed that the process included egress of the merozoites from the infected RBC, gliding motility, and subsequent invasion into new RBCs. The gliding motility of B. bovis merozoites was similar to the helical gliding of Toxoplasma tachyzoites. The trails left by the merozoites were detected by indirect immunofluorescence assay using antiserum against B. bovis merozoite surface antigen 1. Inhibition of gliding motility by actin filament polymerization or depolymerization indicated that the gliding motility was driven by actomyosin dependent process. In addition, we revealed the timing of breakdown of the parasitophorous vacuole. Time-lapse image analysis of membrane-stained bovine RBCs showed formation and breakdown of the parasitophorous vacuole within ten minutes of invasion. Conclusions/Significance This is the first report of the gliding motility of B. bovis. Since merozoites of Plasmodium parasites do not glide on a substrate, the gliding motility of B. bovis merozoites is a notable finding. PMID:22506073

Development of a new fertility prediction model for stallion semen, including flow cytometry.

PubMed

Barrier Battut, I; Kempfer, A; Becker, J; Lebailly, L; Camugli, S; Chevrier, L

2016-09-01

Several laboratories routinely use flow cytometry to evaluate stallion semen quality. However, objective and practical tools for the on-field interpretation of data concerning fertilizing potential are scarce. A panel of nine tests, evaluating a large number of compartments or functions of the spermatozoa: motility, morphology, viability, mitochondrial activity, oxidation level, acrosome integrity, DNA integrity, "organization" of the plasma membrane, and hypoosmotic resistance, was applied to a population of 43 stallions, 33 of which showing widely differing fertilities (19%-84% pregnancy rate per cycle [PRC]). Analyses were performed either within 2 hours after semen collection or after 24-hour storage at 4 °C in INRA96 extender, on three to six ejaculates for each stallion. The aim was to provide data on the distribution of values among said population, showing within-stallion and between-stallion variability, and to determine whether appropriate combinations of tests could evaluate the fertilizing potential of each stallion. Within-stallion repeatability, defined as intrastallion correlation (r = between-stallion variance/total variance) ranged between 0.29 and 0.84 for "conventional" variables (viability, morphology, and motility), and between 0.15 and 0.81 for "cytometric" variables. Those data suggested that analyzing six ejaculates would be adequate to characterize a stallion. For most variables, except those related to DNA integrity and some motility variables, results differed significantly between immediately performed analyses and analyses performed after 24 hours at 4 °C. Two "best-fit" combinations of variables were determined. Factorial discriminant analysis using a first combination of seven variables, including the polarization of mitochondria, acrosome integrity, DNA integrity, and hypoosmotic resistance, permitted exact determination of the fertility group for each stallion: fertile, that is, PRC higher than 55%; intermediate, that is, 45% < PRC less than 55%; or subfertile, that is, PRC less than 45%. Linear regression using another combination of 20 variables, including motility, viability, oxidation level, acrosome integrity, DNA integrity, and hypoosmotic resistance, accounted for 94.2% of the variability regarding fertility and was used to calculate a prediction of the PRC with a mean standard deviation of 3.1. The difference between the observed fertility and the calculated value ranged from -4.2 to 5.0. In conclusion, this study enabled to determine a new protocol for the evaluation of stallion semen, combining microscopical observation, computer-assisted motility analysis and flow cytometry, and providing a high level of fertility prediction. Copyright © 2016 Elsevier Inc. All rights reserved.

Environmental osmolality influences sperm motility activation in an anuran amphibian.

PubMed

Byrne, P G; Dunne, C; Munn, A J; Silla, A J

2015-03-01

Evolutionary theory predicts that selection will favour sperm traits that maximize fertilization success in local fertilization environments. In externally fertilizing species, osmolality of the fertilization medium is known to play a critical role in activating sperm motility, but there remains limited evidence for adaptive responses to local osmotic environments. In this study, we used a split-sample experimental design and computer-assisted sperm analysis to (i) determine the optimal medium osmolality for sperm activation (% sperm motility and sperm velocity) in male common eastern froglets (Crinia signifera), (ii) test for among-population variation in percentage sperm motility and sperm velocity at various activation-medium osmolalities and (iii) test for among-population covariation between sperm performance and environmental osmolality. Frogs were obtained from nine populations that differed in environmental osmolality, and sperm samples of males from different populations were subjected to a range of activation-medium osmolalities. Percentage sperm motility was optimal between 10 and 50 mOsm kg(-1) , and sperm velocity was optimal between 10 and 100 mOsm kg(-1) , indicating that C. signifera has evolved sperm that can function across a broad range of osmolalities. As predicted, there was significant among-population variation in sperm performance. Furthermore, there was a significant interaction between activation-medium osmolality and environmental osmolality, indicating that frogs from populations with higher environmental osmolality produced sperm that performed better at higher osmolalities in vitro. This finding may reflect phenotypic plasticity in sperm functioning, or genetic divergence resulting from spatial variation in the strength of directional selection. Both of these explanations are consistent with evolutionary theory, providing some of the first empirical evidence that local osmotic environments can favour adaptive sperm motility responses in species that use an external mode of fertilization. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

UnPAKing the class differences among p21-activated kinases.

PubMed

Eswaran, Jeyanthy; Soundararajan, Meera; Kumar, Rakesh; Knapp, Stefan

2008-08-01

The p21-activated kinases (PAKs) are signal transducers, central to many vital cellular processes, including cell morphology, motility, survival, gene transcription and hormone signalling. The mammalian PAK family contains six serine/threonine kinases divided into two subgroups, group I (PAK 1-3) and group II (PAK4-6), based on their domain architecture and regulation. PAKs functioning as dynamic signalling nodes present themselves as attractive therapeutic targets in tumours, neurological diseases and infection. The recent findings across all PAKs, including newly reported structures, shed light on the cellular functions of PAKs, highlighting molecular mechanisms of activation, catalysis and substrate specificity. We believe that a comprehensive understanding of the entire PAK family is essential for developing strategies towards PAK-targeted therapeutics.

Total motile sperm count has a superior predictive value over the WHO 2010 cut-off values for the outcomes of intracytoplasmic sperm injection cycles.

PubMed

Borges, E; Setti, A S; Braga, D P A F; Figueira, R C S; Iaconelli, A

2016-09-01

The objective of this study was to compare (i) the intracytoplasmic sperm injection outcomes among groups with different total motile sperm count ranges, (ii) the intracytoplasmic sperm injection outcomes between groups with normal and abnormal total motile sperm count, and (iii) the predictive values of WHO 2010 cut-off values and pre-wash total motile sperm count for the intracytoplasmic sperm injection outcomes, in couples with male infertility. This study included data from 518 patients undergoing their first intracytoplasmic sperm injection cycle as a result of male infertility. Couples were divided into five groups according to their total motile sperm count: Group I, total motile sperm count <1 × 10(6) ; group II, total motile sperm count 1-5 × 10(6) ; group III, total motile sperm count 5-10 × 10(6) ; group IV, total motile sperm count 10-20 × 10(6) ; and group V, total motile sperm count >20 × 10(6) (which was considered a normal total motile sperm count value). Then, couples were grouped into an abnormal and normal total motile sperm count group. The groups were compared regarding intracytoplasmic sperm injection outcomes. The predictive values of WHO 2010 cut-off values and total motile sperm count for the intracytoplasmic sperm injection outcomes were also investigated. The fertilization rate was lower in total motile sperm count group I compared to total motile sperm count group V (72.5 ± 17.6 vs. 84.9 ± 14.4, p = 0.011). The normal total motile sperm count group had a higher fertilization rate (84.9 ± 14.4 vs. 81.1 ± 15.8, p = 0.016) and lower miscarriage rate (17.9% vs. 29.5%, p = 0.041) compared to the abnormal total motile sperm count group. The total motile sperm count was the only parameter that demonstrated a predictive value for the formation of high-quality embryos on D2 (OR: 1.18, p = 0.013), formation of high-quality embryos on D3 (OR: 1.12, p = 0.037), formation of blastocysts on D5 (OR: 1.16, p = 0.011), blastocyst expansion grade on D5 (OR: 1.27, p = 0.042), and the odds of miscarriage (OR: 0.52, p < 0.045). The total motile sperm count has a greater predictive value than the WHO 2010 cut-off values for laboratory results and pregnancy outcomes in couples undergoing intracytoplasmic sperm injection as a result of male infertility. © 2016 American Society of Andrology and European Academy of Andrology.

UCS protein Rng3p activates actin filament gliding by fission yeast myosin-II

PubMed Central

Lord, Matthew; Pollard, Thomas D.

2004-01-01

We purified native Myo2p/Cdc4p/Rlc1p (Myo2), the myosin-II motor required for cytokinesis by Schizosaccharomyces pombe. The Myo2p heavy chain associates with two light chains, Cdc4p and Rlc1p. Although crude Myo2 supported gliding motility of actin filaments in vitro, purified Myo2 lacked this activity in spite of retaining full Ca-ATPase activity and partial actin-activated Mg-ATPase activity. Unc45-/Cro1p-/She4p-related (UCS) protein Rng3p restored the full motility and actin-activated Mg-ATPase activity of purified Myo2. The COOH-terminal UCS domain of Rng3p alone restored motility to pure Myo2. Thus, Rng3p contributes directly to the motility activity of native Myo2. Consistent with a role in Myo2 activation, Rng3p colocalizes with Myo2p in the cytokinetic contractile ring. The absence of Rlc1p or mutations in the Myo2p head or Rng3p compromise the in vitro motility of Myo2 and explain the defects in cytokinesis associated with some of these mutations. In contrast, Myo2 with certain temperature-sensitive forms of Cdc4p has normal motility, so these mutations compromise other functions of Cdc4p required for cytokinesis. PMID:15504913

RON kinase isoforms demonstrate variable cell motility in normal cells.

PubMed

Greenbaum, Alissa; Rajput, Ashwani; Wan, Guanghua

2016-09-01

Aberrant RON (Recepteur d'Origine Nantais) tyrosine kinase activation causes the epithelial cell to evade normal growth pathways, resulting in unregulated cell proliferation, increased cell motility and decreased apoptosis. Wildtype (wt) RON has been shown to play a role in metastasis of epithelial malignancies. It presents an important potential therapeutic target for colorectal, breast, gastric and pancreatic cancer. Little is known about functional differences amongst RON isoforms RON155, RON160 and RON165. The purpose of this study was to determine the effect of various RON kinase isoforms on cell motility. Cell lines with stable expression of wtRON were generated by inserting the coding region of RON in pTagRFP (tagged red fluorescence protein plasmid). The expression constructs of RON variants (RON155, RON160 and RON165) were generated by creating a mutagenesis-based wtRON-pTag RFP plasmid and stably transfected into HEK 293 cells. The wound closure scratch assay was used to investigate the effect on cell migratory capacity of wild type RON and its variants. RON transfected cells demonstrated increased cell motility compared to HEK293 control cells. RON165 cell motility was significantly increased compared to RON160 (mean percentage of wound covered 37.37% vs. 32.40%; p = 0.03). RON tyrosine kinase isoforms have variable cell motility. This may reflect a difference in the behavior of malignant epithelial cells and their capacity for metastasis.

Crystal structure analysis reveals Pseudomonas PilY1 as an essential calcium-dependent regulator of bacterial surface motility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orans, Jillian; Johnson, Michael D.L.; Coggan, Kimberly A.

Several bacterial pathogens require the 'twitching' motility produced by filamentous type IV pili (T4P) to establish and maintain human infections. Two cytoplasmic ATPases function as an oscillatory motor that powers twitching motility via cycles of pilus extension and retraction. The regulation of this motor, however, has remained a mystery. We present the 2.1 {angstrom} resolution crystal structure of the Pseudomonas aeruginosa pilus-biogenesis factor PilY1, and identify a single site on this protein required for bacterial translocation. The structure reveals a modified {beta}-propeller fold and a distinct EF-hand-like calcium-binding site conserved in pathogens with retractile T4P. We show that preventing calciummore » binding by PilY1 using either an exogenous calcium chelator or mutation of a single residue disrupts Pseudomonas twitching motility by eliminating surface pili. In contrast, placing a lysine in this site to mimic the charge of a bound calcium interferes with motility in the opposite manner - by producing an abundance of nonfunctional surface pili. Our data indicate that calcium binding and release by the unique loop identified in the PilY1 crystal structure controls the opposing forces of pilus extension and retraction. Thus, PilY1 is an essential, calcium-dependent regulator of bacterial twitching motility.« less

High-Resolution Manometry Evaluation of the Pharynx and Upper Esophageal Sphincter Motility in Patients with Achalasia.

PubMed

Menezes, Mariano A; Herbella, Fernando A M; Patti, Marco G

2015-10-01

The motility of the pharynx and upper esophageal sphincter (UES) is still poorly understood. It is also unclear if the motility of this area may be compromised in patients with achalasia. This study aims to evaluate the motility of the pharynx, UES, and proximal esophagus in patients with esophageal achalasia. Sixty patients with achalasia underwent high-resolution manometry (HRM) (52 % females, mean age 54 years). Esophageal dilatation was classified according to the radiologic diameter in Type I (<4 cm): 6 %; Type II (4-7 cm): 36 %; Type III (7-10 cm): 34 %; and Type IV (>10 cm): 24 %. HRM classified 43 % of the patients as Chicago Type I and 57 % as Type II. Manometric parameters were compared to normal values obtained from a previous study in volunteers. The motility of the velopharynx showed short, premature, and hypertonic contraction. The epiglottis also showed hypertonic contraction. The UES had increased residual pressure. Chicago classification Type II patients had higher UES residual pressure (p = 0.03). The degree of esophageal dilatation did not correlate with manometric parameters. Achalasia may affect the motility of the pharyngo-upper esophageal area. The changes observed may represent functional alterations to prevent aspiration, especially in patients with Chicago classification Type II achalasia.

Cell motility in cancer invasion and metastasis: insights from simple model organisms.

PubMed

Stuelten, Christina H; Parent, Carole A; Montell, Denise J

2018-05-01

Metastasis remains the greatest challenge in the clinical management of cancer. Cell motility is a fundamental and ancient cellular behaviour that contributes to metastasis and is conserved in simple organisms. In this Review, we evaluate insights relevant to human cancer that are derived from the study of cell motility in non-mammalian model organisms. Dictyostelium discoideum, Caenorhabditis elegans, Drosophila melanogaster and Danio rerio permit direct observation of cells moving in complex native environments and lend themselves to large-scale genetic and pharmacological screening. We highlight insights derived from each of these organisms, including the detailed signalling network that governs chemotaxis towards chemokines; a novel mechanism of basement membrane invasion; the positive role of E-cadherin in collective direction-sensing; the identification and optimization of kinase inhibitors for metastatic thyroid cancer on the basis of work in flies; and the value of zebrafish for live imaging, especially of vascular remodelling and interactions between tumour cells and host tissues. While the motility of tumour cells and certain host cells promotes metastatic spread, the motility of tumour-reactive T cells likely increases their antitumour effects. Therefore, it is important to elucidate the mechanisms underlying all types of cell motility, with the ultimate goal of identifying combination therapies that will increase the motility of beneficial cells and block the spread of harmful cells.

Image velocimetry and spectral analysis enable quantitative characterization of larval zebrafish gut motility.

PubMed

Ganz, J; Baker, R P; Hamilton, M K; Melancon, E; Diba, P; Eisen, J S; Parthasarathy, R

2018-05-02

Normal gut function requires rhythmic and coordinated movements that are affected by developmental processes, physical and chemical stimuli, and many debilitating diseases. The imaging and characterization of gut motility, especially regarding periodic, propagative contractions driving material transport, are therefore critical goals. Previous image analysis approaches have successfully extracted properties related to the temporal frequency of motility modes, but robust measures of contraction magnitude, especially from in vivo image data, remain challenging to obtain. We developed a new image analysis method based on image velocimetry and spectral analysis that reveals temporal characteristics such as frequency and wave propagation speed, while also providing quantitative measures of the amplitude of gut motion. We validate this approach using several challenges to larval zebrafish, imaged with differential interference contrast microscopy. Both acetylcholine exposure and feeding increase frequency and amplitude of motility. Larvae lacking enteric nervous system gut innervation show the same average motility frequency, but reduced and less variable amplitude compared to wild types. Our image analysis approach enables insights into gut dynamics in a wide variety of developmental and physiological contexts and can also be extended to analyze other types of cell movements. © 2018 John Wiley & Sons Ltd.

Stress-related alterations of acyl and desacyl ghrelin circulating levels: mechanisms and functional implications

PubMed Central

Stengel, Andreas; Wang, Lixin; Taché, Yvette

2011-01-01

Ghrelin is the only known peripherally produced and centrally acting peptide hormone that stimulates food intake and digestive functions. Ghrelin circulates as acylated and desacylated forms and recently the acylating enzyme, ghrelin-O-acyltransferase (GOAT) and the de-acylating enzyme, thioesterase 1/lysophospholipase 1 have been identified adding new layers of complexity to the regulation of ghrelin. Stress is known to alter gastrointestinal motility and food intake and was recently shown to modify circulating ghrelin and GOAT levels with differential responses related to the type of stressors including a reduction induced by physical stressors (abdominal surgery and immunological/endotoxin injection, exercise) and elevation by metabolic (cold exposure, fasting and caloric restriction) and psychological stressors. However, the pathways underlying the alterations of ghrelin under these various stress conditions are still largely to be defined and may relate to stress-associated autonomic changes. There is evidence that alterations of circulating ghrelin may contribute to the neuroendocrine and behavioral responses along with sustaining the energetic requirement needed upon repeated exposure to stressors. A better understanding of these mechanisms will allow targeting components of ghrelin signaling that may improve food intake and gastric motility alterations induced by stress. PMID:21782868

Stress-related alterations of acyl and desacyl ghrelin circulating levels: mechanisms and functional implications.

PubMed

Stengel, Andreas; Wang, Lixin; Taché, Yvette

2011-11-01

Ghrelin is the only known peripherally produced and centrally acting peptide hormone that stimulates food intake and digestive functions. Ghrelin circulates as acylated and desacylated forms and recently the acylating enzyme, ghrelin-O-acyltransferase (GOAT) and the de-acylating enzyme, thioesterase 1/lysophospholipase 1 have been identified adding new layers of complexity to the regulation of ghrelin. Stress is known to alter gastrointestinal motility and food intake and was recently shown to modify circulating ghrelin and GOAT levels with differential responses related to the type of stressors including a reduction induced by physical stressors (abdominal surgery and immunological/endotoxin injection, exercise) and elevation by metabolic (cold exposure, acute fasting and caloric restriction) and psychological stressors. However, the pathways underlying the alterations of ghrelin under these various stress conditions are still largely to be defined and may relate to stress-associated autonomic changes. There is evidence that alterations of circulating ghrelin may contribute to the neuroendocrine and behavioral responses along with sustaining the energetic requirement needed upon repeated exposure to stressors. A better understanding of these mechanisms will allow targeting components of ghrelin signaling that may improve food intake and gastric motility alterations induced by stress. Published by Elsevier Inc.

Function of the alpha 6 Integrins in Breast Carcinoma

DTIC Science & Technology

2001-10-01

motility on laminin-1. Time-lapse was resistant to solubilization with Triton X-100. Cy- videomicroscopy of clone A cells on laminin-1 revealed...represent SEM. The Integrin a6/34 Participates in the Dynamic Formation of Actin-based Motility Structures: Filopodia lapse videomicroscopy in serum-free...threefold greater time-lapse videomicroscopy to understand how the cu6P34 than on an equivalent concentration of collagen type I, integrin contributes to

Inhibitory neurotransmission regulates vagal efferent activity and gastric motility

PubMed Central

McMenamin, Caitlin A; Travagli, R Alberto

2016-01-01

The gastrointestinal tract receives extrinsic innervation from both the sympathetic and parasympathetic nervous systems, which regulate and modulate the function of the intrinsic (enteric) nervous system. The stomach and upper gastrointestinal tract in particular are heavily influenced by the parasympathetic nervous system, supplied by the vagus nerve, and disruption of vagal sensory or motor functions results in disorganized motility patterns, disrupted receptive relaxation and accommodation, and delayed gastric emptying, amongst others. Studies from several laboratories have shown that the activity of vagal efferent motoneurons innervating the upper GI tract is inhibited tonically by GABAergic synaptic inputs from the adjacent nucleus tractus solitarius. Disruption of this influential central GABA input impacts vagal efferent output, hence gastric functions, significantly. The purpose of this review is to describe the development, physiology, and pathophysiology of this functionally dominant inhibitory synapse and its role in regulating vagally determined gastric functions. PMID:27302177

Fluorometric assessments of viability and mitochondrial status of boar spermatozoa following liquid storage.

PubMed

Fraser, L; Lecewicz, M; Strzezek, J

2002-01-01

A study was conducted to assess viability and mitochondrial status of boar spermatozoa stored at 5 degrees C and 16 degrees C. Gel-free ejaculates, collected from 3 mature boars, were extended in a standard diluent (K3) supplemented with a low-density lipoprotein fraction (LDF) isolated from egg yolk, and stored for 96 h at 5 degrees C and 16 degrees C. Motility analysis was conducted after semen dilution (D0) and on D1-D4 of storage. A double staining method, rhodamine 123 (R123) and propidium iodide (PI), was used to assess sperm viability and mitochondrial status. Sperm viability was also assessed using Hoechst 33,258 (H33258) stain. In fresh semen samples, the percentage of motility was significantly correlated with the percentage of viable spermatozoa with functional mitochondria (R123-PI), viable spermatozoa determined by H33258 staining and ATP content (r = 0.88, p < or = 0.01; r = 0.69, p < or = 0.05; r = 0.77, p < or = 0.01, respectively). The ATP content was also positively correlated with the percentage of viable spermatozoa with functional mitochondria (r = 0.76, p < or = 0.01). Sperm cells progressively lost motility, viability and mitochondrial capacity when stored in the supportive media at 5 degrees C and 16 degrees C. Motility estimates were lower (p < or = 0.05) than the percentage of viable spermatozoa with functional mitochondria during storage in K3 and LDF-based diluents on D4 and D3-D4, respectively. Deterioration in motility and membrane integrity was less marked in spermatozoa stored in LDF-based diluents. Spermatozoa doubly-stained with R123-PI appeared to possess some functional mitochondria, particularly in LDF-based diluent semen. Estimates of sperm viability, as determined by R123-PI staining, were equivalent (p > or = 0.05) to estimates made using H33258 staining. A decrease in mitochondrial activity, as measured by R123 uptake, was accompanied by lower ATP content in spermatozoa stored in K3 and LDF-based diluents after 48 h and 72 h of storage, respectively. Fluorometric measurements of viability and mitochondrial status of boar spermatozoa during liquid storage seem to provide reliable information about the sperm functional membranes.

Oesophageal motility disorders in infected immigrants with Chagas disease in a non-endemic European area

PubMed Central

Valerio, Lluís; Vallès, Xavier; Morales, Betty; Garcia-Diaz, M Immaculada; Pedro-Botet, M Luisa; Serra, Jordi

2016-01-01

Background Immigration-related new diseases pose a growing challenge for healthcare services in receptor countries. Following Latin American migration, Chagas disease has inevitably appeared in Europe. Aim To determine the prevalence and characteristics of oesophageal motility disorders in immigrants infected with Trypanosoma cruzi, using high resolution oesophageal manometry (HREM). Methods In all newly-diagnosed cases with chronic Chagas infection referring upper digestive symptoms, a protocolized clinical evaluation and complementary tests including barium oesophagogram and HREM were carried out. As control group, 14 healthy subjects from the same endemic areas were studied with HREM. Results We included 61 patients (46 female, 15 male; age range 26–63 years). Only seven patients (11%) had a minor alteration on barium oesophagogram. By contrast, 23 (37%) patients showed an alteration in oesophageal manometry, mainly minor motility disorders (34%). Only one healthy control (7%) had a minor motility disorder at HREM (p = 0.029 vs. patients). Conclusions Oesophageal motor disorders in infected immigrants with Chagas disease are common, and mainly characterized by a minor motility disorder that is not detected by barium oesophagogram. Hence, as well as barium oesophagogram examination, HREM should be considered, to assess oesophageal damage in this specific group of patients. PMID:27536373

Analyzing Neutrophil Morphology, Mechanics, and Motility in Sepsis: Options and Challenges for Novel Bedside Technologies.

PubMed

Zonneveld, Rens; Molema, Grietje; Plötz, Frans B

2016-01-01

Alterations in neutrophil morphology (size, shape, and composition), mechanics (deformability), and motility (chemotaxis and migration) have been observed during sepsis. We combine summarizing features of neutrophil morphology, mechanics, and motility that change during sepsis with an investigation into their clinical utility as markers for sepsis through measurement with novel technologies. We performed an initial literature search in MEDLINE using search terms "neutrophil," "morphology," "mechanics," "dynamics," "motility," "mobility," "spreading," "polarization," "migration," and "chemotaxis." We then combined the results with "sepsis" and "septic shock." We scanned bibliographies of included articles to identify additional articles. Final selection was done after the authors reviewed recovered articles. We included articles based on their relevance for our review topic. When compared with resting conditions, sepsis causes an increase in circulating numbers of larger, more rigid neutrophils that show diminished granularity, migration, and chemotaxis. Combined measurement of these variables could provide a more complete view on neutrophil phenotype manifestation. For that purpose, sophisticated automated hematology analyzers, microscopy, and bedside microfluidic devices provide clinically feasible, high-throughput, and cost-limiting means. We propose that integration of features of neutrophil morphology, mechanics, and motility with these new analytical methods can be useful as markers for diagnosis, prognosis, and monitoring of sepsis and may even contribute to basic understanding of its pathophysiology.

Glycolytic enzyme activity is essential for domestic cat (Felis catus) and cheetah (Acinonyx jubatus) sperm motility and viability in a sugar-free medium.

PubMed

Terrell, Kimberly A; Wildt, David E; Anthony, Nicola M; Bavister, Barry D; Leibo, S P; Penfold, Linda M; Marker, Laurie L; Crosier, Adrienne E

2011-06-01

We have previously reported a lack of glucose uptake in domestic cat and cheetah spermatozoa, despite observing that these cells produce lactate at rates that correlate positively with sperm function. To elucidate the role of glycolysis in felid sperm energy production, we conducted a comparative study in the domestic cat and cheetah, with the hypothesis that sperm motility and viability are maintained in both species in the absence of glycolytic metabolism and are fueled by endogenous substrates. Washed ejaculates were incubated in chemically defined medium in the presence/absence of glucose and pyruvate. A second set of ejaculates was exposed to a chemical inhibitor of either lactate dehydrogenase (sodium oxamate) or glyceraldehyde-3-phosphate dehydrogenase (alpha-chlorohydrin). Sperm function (motility and acrosomal integrity) and lactate production were assessed, and a subset of spermatozoa was assayed for intracellular glycogen. In both the cat and cheetah, sperm function was maintained without exogenous substrates and following lactate dehydrogenase inhibition. Lactate production occurred in the absence of exogenous hexoses, but only if pyruvate was present. Intracellular glycogen was not detected in spermatozoa from either species. Unexpectedly, glycolytic inhibition by alpha-chlorohydrin resulted in an immediate decline in sperm motility, particularly in the domestic cat. Collectively, our findings reveal an essential role of the glycolytic pathway in felid spermatozoa that is unrelated to hexose metabolism or lactate formation. Instead, glycolytic enzyme activity could be required for the metabolism of endogenous lipid-derived glycerol, with fatty acid oxidation providing the primary energy source in felid spermatozoa.

Src family kinase expression and subcellular localization in macrophages: implications for their role in CSF-1-induced macrophage migration.

PubMed

Dwyer, Amy R; Mouchemore, Kellie A; Steer, James H; Sunderland, Andrew J; Sampaio, Natalia G; Greenland, Eloise L; Joyce, David A; Pixley, Fiona J

2016-07-01

A major role of colony-stimulating factor-1 is to stimulate the differentiation of mononuclear phagocytic lineage cells into adherent, motile, mature macrophages. The colony-stimulating factor-1 receptor transduces colony-stimulating factor-1 signaling, and we have shown previously that phosphatidylinositol 3-kinase p110δ is a critical mediator of colony-stimulating factor-1-stimulated motility through the colony-stimulating factor-1 receptor pY721 motif. Src family kinases are also implicated in the regulation of macrophage motility and in colony-stimulating factor-1 receptor signaling, although functional redundancy of the multiple SFKs expressed in macrophages makes it challenging to delineate their specific functions. We report a comprehensive analysis of individual Src family kinase expression in macrophage cell lines and primary macrophages and demonstrate colony-stimulating factor-1-induced changes in Src family kinase subcellular localization, which provides clues to their distinct and redundant functions in macrophages. Moreover, expression of individual Src family kinases is both species specific and dependent on colony-stimulating factor-1-induced macrophage differentiation. Hck associated with the activated colony-stimulating factor-1 receptor, whereas Lyn associated with the receptor in a constitutive manner. Consistent with this, inhibitor studies revealed that Src family kinases were important for both colony-stimulating factor-1 receptor activation and colony-stimulating factor-1-induced macrophage spreading, motility, and invasion. Distinct colony-stimulating factor-1-induced changes in the subcellular localization of individual SFKs suggest specific roles for these Src family kinases in the macrophage response to colony-stimulating factor-1. © Society for Leukocyte Biology.

EGF-like peptide-enhanced cell motility in Dictyostelium functions independently of the cAMP-mediated pathway and requires active Ca2+/calmodulin signaling.

PubMed

Huber, Robert; O'Day, Danton H

2011-04-01

Current knowledge suggests that cell movement in the eukaryotic slime mold Dictyostelium discoideum is mediated by different signaling pathways involving a number of redundant components. Our previous research has identified a specific motility-enhancing function for epidermal growth factor-like (EGFL) repeats in Dictyostelium, specifically for the EGFL repeats of cyrA, a matricellular, calmodulin (CaM)-binding protein in Dictyostelium. Using mutants of cAMP signaling (carA(-), carC(-), gpaB(-), gpbA(-)), the endogenous calcium (Ca(2+)) release inhibitor TMB-8, the CaM antagonist W-7, and a radial motility bioassay, we show that DdEGFL1, a synthetic peptide whose sequence is obtained from the first EGFL repeat of cyrA, functions independently of the cAMP-mediated signaling pathways to enhance cell motility through a mechanism involving Ca(2+) signaling, CaM, and RasG. We show that DdEGFL1 increases the amounts of polymeric myosin II heavy chain and actin in the cytoskeleton by 24.1±10.7% and 25.9±2.1% respectively and demonstrate a link between Ca(2+)/CaM signaling and cytoskeletal dynamics. Finally, our findings suggest that carA and carC mediate a brake mechanism during chemotaxis since DdEGFL1 enhanced the movement of carA(-)/carC(-) cells by 844±136% compared to only 106±6% for parental DH1 cells. Based on our data, this signaling pathway also appears to involve the G-protein β subunit, RasC, RasGEFA, and protein kinase B. Together, our research provides insight into the functionality of EGFL repeats in Dictyostelium and the signaling pathways regulating cell movement in this model organism. It also identifies several mechanistic components of DdEGFL1-enhanced cell movement, which may ultimately provide a model system for understanding EGFL repeat function in higher organisms. Copyright © 2010 Elsevier Inc. All rights reserved.

Analysis of the effects of polyphenols on human spermatozoa reveals unexpected impacts on mitochondrial membrane potential, oxidative stress and DNA integrity; implications for assisted reproductive technology.

PubMed

Aitken, R J; Muscio, L; Whiting, S; Connaughton, H S; Fraser, B A; Nixon, B; Smith, N D; De Iuliis, G N

2016-12-01

The need to protect human spermatozoa from oxidative stress during assisted reproductive technology, has prompted a detailed analysis of the impacts of phenolic compounds on the functional integrity of these cells. Investigation of 16 individual compounds revealed a surprising variety of negative effects including: (i) a loss of mitochondrial membrane potential (Δψm) via mechanisms that were not related to opening of the permeability transition pore but associated with a reduction in thiol expression, (ii) a decline in intracellular reduced glutathione, (iii) the stimulation of pro-oxidant activity including the induction of ROS generation from mitochondrial and non-mitochondrial sources, (iv) stimulation of lipid peroxidation, (v) the generation of oxidative DNA damage, and (vi) impaired sperm motility. For most of the polyphenolic compounds examined, the loss of motility was gradual and highly correlated with the induction of lipid peroxidation (r=0.889). The exception was gossypol, which induced a rapid loss of motility due to its inherent alkylating activity; one consequence of which was a marked reduction in carboxymethyl lysine expression on the sperm tail; a post-translational modification that is known to play a key role in the regulation of sperm movement. The only polyphenols that did not appear to have adverse effects on spermatozoa were resveratrol, genistein and THP at doses below 100μM. These compounds could, therefore, have some therapeutic potential in a clinical setting. Copyright © 2016 Elsevier Inc. All rights reserved.

Intestinal crosstalk between microbiota and serotonin and its impact on gut motility.

PubMed

Ge, Xiaolong; Pan, Junhai; Liu, Yichang; Wang, Hongkan; Zhou, Wei; Wang, Xianfa

2018-05-27

The gastrointestinal tract harbours a diverse bacterial community that contributes to health and disease. A number of studies have demonstrated that the gut microbiota plays a critical role in the metabolism of serotonin. Microbial-derived metabolites, such as bile acids and short-chain fatty acids, are reported to affect the production of serotonin which, in turn, directly or indirectly regulates gut motility. Enterochromaffin cells are important specialized endocrine cells found in the intestine, which is the major location of serotonin biosynthesis. The relationship between microbiota and gut motility are studied depended on microbial-derived metabolites and serotonin. Both bile acids and short-chain fatty acids can modulate serotonin metabolism in hosts by affecting key intermediates of the serotonin pathway. Thus, gut motility may be regulated through microbial modifications of host serotonin biosynthesis, which continues to be evaluated as a target for functional gastrointestinal disorders. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Intermittent Ca2+ signals mediated by Orai1 regulate basal T cell motility

PubMed Central

Greenberg, Milton L; Jairaman, Amit; Akunwafo, Chijioke; Leverrier, Sabrina; Yu, Ying; Parker, Ian; Dynes, Joseph L

2017-01-01

Ca2+ influx through Orai1 channels is crucial for several T cell functions, but a role in regulating basal cellular motility has not been described. Here, we show that inhibition of Orai1 channel activity increases average cell velocities by reducing the frequency of pauses in human T cells migrating through confined spaces, even in the absence of extrinsic cell contacts or antigen recognition. Utilizing a novel ratiometric genetically encoded cytosolic Ca2+ indicator, Salsa6f, which permits real-time monitoring of cytosolic Ca2+ along with cell motility, we show that spontaneous pauses during T cell motility in vitro and in vivo coincide with episodes of cytosolic Ca2+ signaling. Furthermore, lymph node T cells exhibited two types of spontaneous Ca2+ transients: short-duration ‘sparkles’ and longer duration global signals. Our results demonstrate that spontaneous and self-peptide MHC-dependent activation of Orai1 ensures random walk behavior in T cells to optimize immune surveillance. PMID:29239723

H-NS represses transcription of the flagellin gene lafA of lateral flagella in Vibrio parahaemolyticus.

PubMed

Wang, Yan; Zhang, Yiquan; Yin, Zhe; Wang, Jie; Zhu, Yongzhe; Peng, Haoran; Zhou, Dongsheng; Qi, Zhongtian; Yang, Wenhui

2018-01-01

Swarming motility is ultimately mediated by the proton-powered lateral flagellar (laf) system in Vibrio parahaemolyticus. Expression of laf genes is tightly regulated by a number of environmental conditions and regulatory factors. The nucleoid-associated DNA-binding protein H-NS is a small and abundant protein that is widely distributed in bacteria, and H-NS-like protein-dependent expression of laf genes has been identified in Vibrio cholerae and V. parahaemolyticus. The data presented here show that H-NS acts as a repressor of the swarming motility in V. parahaemolyticus. A single σ 28 -dependent promoter was detected for lafA encoding the flagellin of the lateral flagella, and its activity was directly repressed by H-NS. Thus, H-NS represses swarming motility by directly acting on lafA. Briefly, this work revealed a novel function for H-NS as a repressor of the expression of lafA and swarming motility in V. parahaemolyticus.

Multidrug-resistant Salmonella enterica serovar Typhimurium isolates are resistant to antibiotics that influence their swimming and swarming motility

USDA-ARS?s Scientific Manuscript database

Motile bacteria utilize one or more strategies for movement, such as darting, gliding, sliding, swarming, swimming, and twitching. The ability to move is considered a virulence factor in many pathogenic bacteria, including Salmonella. Multidrug-resistant (MDR) Salmonella encodes acquired factors t...

Automated measurement of cell motility and proliferation

PubMed Central

Bahnson, Alfred; Athanassiou, Charalambos; Koebler, Douglas; Qian, Lei; Shun, Tongying; Shields, Donna; Yu, Hui; Wang, Hong; Goff, Julie; Cheng, Tao; Houck, Raymond; Cowsert, Lex

2005-01-01

Background Time-lapse microscopic imaging provides a powerful approach for following changes in cell phenotype over time. Visible responses of whole cells can yield insight into functional changes that underlie physiological processes in health and disease. For example, features of cell motility accompany molecular changes that are central to the immune response, to carcinogenesis and metastasis, to wound healing and tissue regeneration, and to the myriad developmental processes that generate an organism. Previously reported image processing methods for motility analysis required custom viewing devices and manual interactions that may introduce bias, that slow throughput, and that constrain the scope of experiments in terms of the number of treatment variables, time period of observation, replication and statistical options. Here we describe a fully automated system in which images are acquired 24/7 from 384 well plates and are automatically processed to yield high-content motility and morphological data. Results We have applied this technology to study the effects of different extracellular matrix compounds on human osteoblast-like cell lines to explore functional changes that may underlie processes involved in bone formation and maintenance. We show dose-response and kinetic data for induction of increased motility by laminin and collagen type I without significant effects on growth rate. Differential motility response was evident within 4 hours of plating cells; long-term responses differed depending upon cell type and surface coating. Average velocities were increased approximately 0.1 um/min by ten-fold increases in laminin coating concentration in some cases. Comparison with manual tracking demonstrated the accuracy of the automated method and highlighted the comparative imprecision of human tracking for analysis of cell motility data. Quality statistics are reported that associate with stage noise, interference by non-cell objects, and uncertainty in the outlining and positioning of cells by automated image analysis. Exponential growth, as monitored by total cell area, did not linearly correlate with absolute cell number, but proved valuable for selection of reliable tracking data and for disclosing between-experiment variations in cell growth. Conclusion These results demonstrate the applicability of a system that uses fully automated image acquisition and analysis to study cell motility and growth. Cellular motility response is determined in an unbiased and comparatively high throughput manner. Abundant ancillary data provide opportunities for uniform filtering according to criteria that select for biological relevance and for providing insight into features of system performance. Data quality measures have been developed that can serve as a basis for the design and quality control of experiments that are facilitated by automation and the 384 well plate format. This system is applicable to large-scale studies such as drug screening and research into effects of complex combinations of factors and matrices on cell phenotype. PMID:15831094

Estimation of actomyosin active force maintained by tropomyosin and troponin complex under vertical forces in the in vitro motility assay system

PubMed Central

Ishii, Shuya; Kawai, Masataka; Ishiwata, Shin'ichi

2018-01-01

The interaction between actin filaments and myosin molecular motors is a power source of a variety of cellular functions including cell division, cell motility, and muscular contraction. In vitro motility assay examines actin filaments interacting with myosin molecules that are adhered to a substrate (e.g., glass surface). This assay has been the standard method of studying the molecular mechanisms of contraction under an optical microscope. While the force generation has been measured through an optically trapped bead to which an actin filament is attached, a force vector vertical to the glass surface has been largely ignored with the in vitro motility assay. The vertical vector is created by the gap (distance) between the trapped bead and the glass surface. In this report, we propose a method to estimate the angle between the actin filament and the glass surface by optically determining the gap size. This determination requires a motorized stage in a standard epi-fluorescence microscope equipped with optical tweezers. This facile method is applied to force measurements using both pure actin filaments, and thin filaments reconstituted from actin, tropomyosin and troponin. We find that the angle-corrected force per unit filament length in the active condition (pCa = 5.0) decreases as the angle between the filament and the glass surface increases; i.e. as the force in the vertical direction increases. At the same time, we demonstrate that the force on reconstituted thin filaments is approximately 1.5 times larger than that on pure actin filaments. The range of angles we tested was between 11° and 36° with the estimated measurement error less than 6°. These results suggest the ability of cytoplasmic tropomyosin isoforms maintaining actomyosin active force to stabilize cytoskeletal architecture. PMID:29420610

[Analyses of the characteristics of esophageal motility in patients with pharyngeal paraesthesia who visit the Department of gastroenterology].

PubMed

Wang, Zhenjiang; Chen, Yuping; Guo, Tingting

2015-07-01

To investigate the influence of the local sensory abnormality in throat while the change of motility in the upper esophageal sphincter (UES) and lower esophageal sphincter (LES), as well as the change of esophageal body in pharyngeal paraesthesia. From January 2014 to January 2015 there were sixty-four patients who had pharyngeal susceptible syndrome (PSS) but without confirmed organic disease were enrolled as the PSS group, forty healthy volunteers as the control group. High resolution manometry (HRM) was utilized to distinguish esophageal motility patterns of PSS, including the muscular tension of LES and UES, the integrity, adaptability, amplitude, speed and duration of esophageal peristalsis at 10 swallows. The resting LES and UES pressures and the distal contractile integral (DCI) of esophagus in PSS group were lower than that in control group (P < 0.05). The esophageal peristalsis was decelerated and shortened in duration, and amplitude of contraction notably lower in PSS group compared with its counterpart (P < 0.05). The integrity of esophageal peristalsis was impaired in PSS with remarkable changes in motility patterns, involving ratio of major and minor interrupts, and synchronous contraction rate (P < 0.05). As for the time course from relaxation to the lowest pressure point of UES and time for restoration, no definite difference was noticed between the two groups (P > 0.05). The average peak pressure was similar in two groups (P > 0.05). Muscle tension around the UES has no obvious change when pharyngeal paraesthesia occurred, but the reduction of esophageal motor function, clearance ability, anti-reflux gastroesophageal junction, causing the abnormal reflux which hurt the pharyngeal surface mucosa maybe one of the most important reasons leading to pharyngeal paresthesia.

Assessment of semen function and lipid peroxidation among lead exposed men

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasperczyk, Aleksandra; Kasperczyk, Slawomir; Horak, Stanislaw

The study population included healthy, fertile men, employees of Zinc and Lead Metalworks (n = 63). Workers exposed to lead were divided into two groups: a group with moderate exposure to lead (ME) - blood lead level (PbB) 25-40 {mu}g/dl and a group with high exposure to lead (HE) PbB = 40-81 {mu}g/dl. The control group consisted of office workers with no history of occupational exposure to lead. Evaluation of lead, cadmium and zinc level in blood and seminal plasma, zinc protoporphyrin in blood (ZPP), 5-aminolevulinic acid in urine (ALA), malondialdehyde (MDA) in seminal plasma and sperm analysis were performed.more » No differences were noted in the concentration of cadmium and zinc in blood and seminal plasma in the study population. Lipid peroxidation in seminal plasma, represented as MDA concentration, significantly increased by about 56% in the HE group and the percentage of motile sperm cells after 1 h decreased by about 34% in comparison to the control group. No statistically significant correlation between other parameters of sperm analysis and lead exposure parameters nor between lead, cadmium and zinc concentration in blood and seminal plasma were found. A positive association between lead intoxication parameters (PbB, ZPP, lead seminal plasma) and MDA concentration in sperm plasma and inverse correlation with sperm cells motility (PbB, ZPP) was found. An increased concentration of MDA was accompanied by a drop in sperm cells motility. In conclusion, we report that high exposure to lead causes a decrease of sperm motility in men most likely as a result of increased lipid peroxidation, especially if the level in the blood surpasses the concentration of 40 {mu}g/dl.« less

Impact of thoracic surgery on esophageal motor function-Evaluation by high resolution manometry.

PubMed

Wäsche, Anja; Kandulski, Arne; Malfertheiner, Peter; Riedel, Sandra; Zardo, Patrick; Hachenberg, Thomas; Schreiber, Jens

2017-06-01

Alteration of esophageal function is a potential risk factor for postoperative complications in thoracic surgery. This prospective study investigates esophageal motility and function during and after thoracic procedures via high resolution manometry (HRM) and impedance technology with spatiotemporal representation of pressure data. Twelve consecutive patients eligible for elective thoracic surgery underwent preoperative and postoperative (48 hours and 7 days) esophageal HRM. Swallowing acts were carried out with 5 mL of water, 10 mL of water and 1 cm 3 bread in physiological posture to evaluate distal contraction integral (DCI). Length and location of contractile integrity breaks were measured by investigators blinded to the form of surgical intervention. The impact of surgical procedures on esophageal motility was quantified according to current Chicago Classification (CC) criteria. Pre-, intra- and postoperative 24-hour multi-channel impedance pH-metry (MII-pH) was performed to further analyze gastroesophageal reflux patterns. All patients were investigated 48 hours prior to and 7 days after thoracic procedures, with a total of n=675 swallowing acts being included in our study. Increased motility patterns of the tubular esophagus occurred temporally 48 hours postoperatively. DCI 48 hours after surgery increased significantly (5 mL, P=0.049; solid, P=0.014) and returned to baseline values after seven days (5 mL, P=0.039; solid, P=0.039). Break length was significantly reduced 48 hours postoperatively, especially in the proximal esophageal segment (transition zone). Follow-up measurements after another week were comparable to preoperative baseline findings. The perioperative MII-pH measurement showed numerous artifacts caused by intubation and ventilation during surgery also with increasing short and frequent acidic reflux episodes. Thoracic procedures cause a transient modulation of esophageal peristalsis with postoperative increased contractility of the tubular esophagus, presumably without affecting intraesophageal reflex arcs. Although limited by the number of patients, we can conclude on our data that postoperative esophageal hypomotility is unlikely to promote secondary pulmonary complications.

Stimulation of colonic motility by oral PEG electrolyte bowel preparation assessed by MRI: comparison of split vs single dose

PubMed Central

Marciani, L; Garsed, K C; Hoad, C L; Fields, A; Fordham, I; Pritchard, S E; Placidi, E; Murray, K; Chaddock, G; Costigan, C; Lam, C; Jalanka-Tuovinen, J; De Vos, W M; Gowland, P A; Spiller, R C

2014-01-01

Background Most methods of assessing colonic motility are poorly acceptable to patients. Magnetic resonance imaging (MRI) can monitor gastrointestinal motility and fluid distributions. We predicted that a dose of oral polyethylene glycol (PEG) and electrolyte solution would increase ileo-colonic inflow and stimulate colonic motility. We aimed to investigate the colonic response to distension by oral PEG electrolyte in healthy volunteers (HVs) and to evaluate the effect of single 2 L vs split (2 × 1 L) dosing. Methods Twelve HVs received a split dose (1 L the evening before and 1 L on the study day) and another 12 HVs a single dose (2 L on the main study day) of PEG electrolyte. They underwent MRI scans, completed symptom questionnaires, and provided stool samples. Outcomes included small bowel water content, ascending colon motility index, and regional colonic volumes. Key Results Small bowel water content increased fourfold from baseline after ingesting both split (p = 0.0010) and single dose (p = 0.0005). The total colonic volume increase from baseline was smaller for the split dose at 35 ± 8% than for the single dose at 102 ± 27%, p = 0.0332. The ascending colon motility index after treatment was twofold higher for the single dose group (p = 0.0103). Conclusions & Inferences Ingestion of 1 and 2 L PEG electrolyte solution caused a rapid increase in the small bowel and colonic volumes and a robust rise in colonic motility. The increase in both volumes and motility was dose dependent. Such a challenge, being well-tolerated, could be a useful way of assessing colonic motility in future studies. PMID:25060551

Curriculum for neurogastroenterology and motility training: A report from the joint ANMS-ESNM task force.

PubMed

Gyawali, C P; Savarino, E; Lazarescu, A; Bor, S; Patel, A; Dickman, R; Pressman, A; Drewes, A M; Rosen, J; Drug, V; Saps, M; Novais, L; Vazquez-Roque, M; Pohl, D; van Tilburg, M A L; Smout, A; Yoon, S; Pandolfino, J; Farrugia, G; Barbara, G; Roman, S

2018-03-25

Although neurogastroenterology and motility (NGM) disorders are some of the most frequent disorders encountered by practicing gastroenterologists, a structured competency-based training curriculum developed by NGM experts is lacking. The American Neurogastroenterology and Motility Society (ANMS) and the European Society of Neurogastroenterology and Motility (ESNM) jointly evaluated the components of NGM training in North America and Europe. Eleven training domains were identified within NGM, consisting of functional gastrointestinal disorders, visceral hypersensitivity and pain pathways, motor disorders within anatomic areas (esophagus, stomach, small bowel and colon, anorectum), mucosal disorders (gastro-esophageal reflux disease, other mucosal disorders), consequences of systemic disease, consequences of therapy (surgery, endoscopic intervention, medications, other therapy), and transition of pediatric patients into adult practice. A 3-tiered training curriculum covering these domains is proposed here and endorsed by all NGM societies. Tier 1 NGM knowledge and training is expected of all gastroenterology trainees and practicing gastroenterologists. Tier 2 knowledge and training is appropriate for trainees who anticipate NGM disorder management and NGM function test interpretation being an important part of their careers, which may require competency assessment and credentialing of test interpretation skills. Tier 3 knowledge and training is undertaken by trainees interested in a dedicated NGM career and may be restricted to specific domains within the broad NGM field. The joint ANMS and ESNM task force anticipates that the NGM curriculum will streamline NGM training in North America and Europe and will lead to better identification of centers of excellence where Tier 2 and Tier 3 training can be accomplished. © 2018 The Authors. Neurogastroenterology & Motility Published by John Wiley & Sons, Ltd.

L-Carnitine in rooster semen cryopreservation: Flow cytometric, biochemical and motion findings for frozen-thawed sperm.

PubMed

Fattah, A; Sharafi, M; Masoudi, R; Shahverdi, A; Esmaeili, V; Najafi, A

2017-02-01

Rooster semen cryopreservation is not efficient for artificial insemination in breeder flocks. L-Carnitine (LC) has been evaluated for effectiveness in cryopreservation media on the characteristics of rooster sperm after freeze-thawing. Motility characteristics, membrane functionality, abnormal morphology, apoptotic like changes, mitochondria activity and lipid peroxidation of rooster sperms were assessed after freeze-thawing with different concentrations of LC in Beltsville medium. Semen samples were collected from 12 roosters, twice a week, and diluted in the extenders that contained different concentrations of LC. Supplementation of Beltsevile with 1 and 2 mM LC was found to result in higher total motility (68.2± 1.7% and 69.1± 1.7%, respectively), progressive motility (28.4± 1.6%, 29.8± 1.6%), membrane functionality (76.2± 1.9% and 75.9± 1.9%), viability (58.2 ± 1.1%, 59.1 ± 1.1%) and lower significant of lipid peroxidation (2.53 ± 0.08 nmol/ml, 2.49 ± 0.08 nmol/ml) compared to control group containing no LC. Lower motility, progressive motility, and viability were observed in frozen-thawed sperm in extender containing 8 mM LC (35.8± 1.7%, 9.6± 1.2% and 27.1 ± 1.2%, respectively) compared to control. Morphology and mitochondrial activity were not affected by different concentrations of LC. Our results showed that supplementation of Beltsville extender with 1 and 2 mM LC significantly improved the quality of rooster sperm quality after freeze-thawing. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparing the Areas of Interest in the Field of Functional Gastrointestinal Disorder and Neurogastroenterology and Motility Between the East and the West

PubMed Central

Lee, Ju Yup; Kim, Nayoung; Kim, Gwang Ha; Kim, Gi Hyun

2015-01-01

There is a paucity of studies that compare the differences in published articles submitted from the East and the West in the area of neurogastroenterology and motility (NM). To compare the article topics from the East and the West which have been published, 5 Western (Gastroenterology, Gut, American Journal of Gastroenterology, American Journal of Physiology-Gastrointestinal and Liver Physiology, and Neurogastroenterology and Motility) and 3 Eastern gastrointestinal journals (Journal of Gastroenterology, Journal of Gastroenterology and Hepatology, and Journal of Neurogastroenterology and Motility) were selected based on the impact factor. Published papers were classified into 12 categories and 60 subcategories. The titles and abstracts of review articles, original articles, and meta-analyses from these journals were reviewed for the last 2 years (2013–2014). In case of Journal of Neurogastroenterology and Motility which is published quarterly, this search was performed for 5 years (2010–2014). Of the total 2656 reviewed articles, 842 (260 from the East and 582 from the West) were classified into the category of NM. The most frequently published papers from the Western researchers were categorized as brain-gut interaction, visceral hypersensitivity, and irritable bowel syndrome, whereas those from the Eastern researchers were categorized as gastroesophageal reflux disease, functional dyspepsia, and irritable bowel syndrome. This difference between the East and the West is not just due to the journal itself, but it also depends on the author’s affiliation and their ability to perform high quality research in the area of the NM. These data provide evidence for the research trend and give valuable information to the researchers for determining subjects for the study and for selecting proper journals for publishing their studies. PMID:26351091

Sperm quality improvement after date seed oil in vitro supplementation in spontaneous and induced oxidative stress.

PubMed

Fatma, Ben A; Nozha, Chakroun F; Ines, Dammak; Hamadi, Attia; Basma, Hentati; Leila, Ammar K

2009-05-01

In vitro supplementation with date seed oil (DSO) can protect spermatozoa against hydrogen peroxide (H2O2)-mediated damage and can improve sperm function, possibly owing to antioxidant properties. We tested the antioxidant effects of DSO on human sperm motility, sperm viability, reacted acrosome and lipid peroxidation assessed in vitro after H2O2-mediated oxidative damage in spermatozoa. Sixteen patients (mean age: 35 years; range: 25-45 years) referred to the Histology-Embryology Laboratory of the Medicine Faculty of Sfax for semen analysis after 12-24 months of sexual intercourse without conception were selected. After spermiogram, sperm selection by two-interface discontinuous Sill Select gradient was performed, and selected spermatozoa were used in four experimental assays: control; incubation with 100 microm H2O2; incubation with 0.1% DSO; and co-incubation with 0.1% DSO and 100 microm H2O2. Motility and viability were determined using World Health Organization criteria. Acrosome reaction and lipid peroxidation were assessed by staining with fluorescein isothiocyanate-Pisum sativum and spectrophotometric measurement of malondialdehyde, respectively. Results showed that incubation with H2O2 alone led to a significant increase in lipid peroxidation (57.83%, P<0.05) associated with a significant decrease in sperm motility, sperm viability (after 30 min and 24 h) and percentage of reacted acrosome (P<0.05). Date seed oil improved sperm motility after 24 h of incubation (P<0.05) and protected spermatozoa against the deleterious effects of H2O2 on motility, viability, acrosome reaction and lipid peroxidation. We conclude that supplementation with DSO may have a function in antioxidant protection against male infertility.

Dose-response effects of estrogenic mycotoxins (zearalenone, alpha- and beta-zearalenol) on motility, hyperactivation and the acrosome reaction of stallion sperm

PubMed Central

2011-01-01

Background The aim of this study was to investigate the in vitro effects of the Fusarium fungus-derived mycotoxin, zearalenone and its derivatives alpha-zearalenol and beta-zearalenol on motility parameters and the acrosome reaction of stallion sperm. Since the toxic effects of zearalenone and its derivatives are thought to result from their structural similarity to 17beta-estradiol, 17beta-estradiol was used as a positive control for 'estrogen-like' effects. Methods Stallion spermatozoa were exposed in vitro to zearalenone, alpha-zearalenol, beta-zearalenol or 17beta-estradiol at concentrations ranging from 1 pM - 0.1 mM. After 2 hours exposure, motility parameters were evaluated by computer-assisted analysis, and acrosome integrity was examined by flow cytometry after staining with fluoroscein-conjugated peanut agglutinin. Results Mycotoxins affected sperm parameters only at the highest concentration tested (0.1 mM) after 2 hours exposure. In this respect, all of the compounds reduced the average path velocity, but only alpha-zearalenol reduced percentages of motile and progressively motile sperm. Induction of motility patterns consistent with hyperactivation was stimulated according to the following rank of potency: alpha-zearalenol >17beta-estradiol > zearalenone = beta-zearalenol. The hyperactivity-associated changes observed included reductions in straight-line velocity and linearity of movement, and an increase in the amplitude of lateral head displacement, while curvilinear velocity was unchanged. In addition, whereas alpha- and beta- zearalenol increased the percentages of live acrosome-reacted sperm, zearalenone and 17beta-estradiol had no apparent effect on acrosome status. In short, alpha-zearalenol inhibited normal sperm motility, but stimulated hyperactive motility in the remaining motile cells and simultaneously induced the acrosome reaction. Beta-zearalenol induced the acrosome reaction without altering motility. Conversely, zearalenone and 17beta-estradiol did not induce the acrosome reaction but induced hyperactive motility albeit to a different extent. Conclusions Apparently, the mycotoxin zearalenone has 17beta-estradiol-like estrogenic activity that enables it to induce hyperactivated motility of equine sperm cells, whereas the zearalenol derivatives induce premature completion of the acrosome reaction and thereby adversely affect stallion sperm physiology. The alpha form of zearalenol still possessed the estrogenic ability to induce hyperactivated motility, whereas its beta stereo-isomere had lost this property. PMID:21970729

Diguanylate cyclase null mutant reveals that C-Di-GMP pathway regulates the motility and adherence of the extremophile bacterium Acidithiobacillus caldus.

PubMed

Castro, Matías; Deane, Shelly M; Ruiz, Lina; Rawlings, Douglas E; Guiliani, Nicolas

2015-01-01

An understanding of biofilm formation is relevant to the design of biological strategies to improve the efficiency of the bioleaching process and to prevent environmental damages caused by acid mine/rock drainage. For this reason, our laboratory is focused on the characterization of the molecular mechanisms involved in biofilm formation in different biomining bacteria. In many bacteria, the intracellular levels of c-di-GMP molecules regulate the transition from the motile planktonic state to sessile community-based behaviors, such as biofilm development, through different kinds of effectors. Thus, we recently started a study of the c-di-GMP pathway in several biomining bacteria including Acidithiobacillus caldus. C-di-GMP molecules are synthesized by diguanylate cyclases (DGCs) and degraded by phosphodiesterases (PDEs). We previously reported the existence of intermediates involved in c-di-GMP pathway from different Acidithiobacillus species. Here, we report our work related to At. caldus ATCC 51756. We identified several putative-ORFs encoding DGC and PDE and effector proteins. By using total RNA extracted from At. caldus cells and RT-PCR, we demonstrated that these genes are expressed. We also demonstrated the presence of c-di-GMP by mass spectrometry and showed that genes for several of the DGC enzymes were functional by heterologous genetic complementation in Salmonella enterica serovar Typhimurium mutants. Moreover, we developed a DGC defective mutant strain (Δc1319) that strongly indicated that the c-di-GMP pathway regulates the swarming motility and adherence to sulfur surfaces by At. caldus. Together, our results revealed that At. caldus possesses a functional c-di-GMP pathway which could be significant for ores colonization during the bioleaching process.

The Wnt5A/Protein Kinase C Pathway Mediates Motility in Melanoma Cells via the Inhibition of Metastasis Suppressors and Initiation of an Epithelial to Mesenchymal Transition*S

PubMed Central

Dissanayake, Samudra K.; Wade, Michael; Johnson, Carrie E.; O’Connell, Michael P.; Leotlela, Poloko D.; French, Amanda D.; Shah, Kavita V.; Hewitt, Kyle J.; Rosenthal, Devin T.; Indig, Fred E.; Jiang, Yuan; Nickoloff, Brian J.; Taub, Dennis D.; Trent, Jeffrey M.; Moon, Randall T.; Bittner, Michael; Weeraratna, Ashani T.

2008-01-01

We have shown that Wnt5A increases the motility of melanoma cells. To explore cellular pathways involving Wnt5A, we compared gain-of-function (WNT5A stable transfectants) versus loss-of-function (siRNA knockdown) of WNT5A by microarray analysis. Increasing WNT5A suppressed the expression of several genes, which were re-expressed after small interference RNA-mediated knockdown of WNT5A. Genes affected by WNT5A include KISS-1, a metastasis suppressor, and CD44, involved in tumor cell homing during metastasis. This could be validated at the protein level using both small interference RNA and recombinant Wnt5A (rWnt5A). Among the genes up-regulated by WNT5A was the gene vimentin, associated with an epithelial to mesenchymal transition (EMT), which involves decreases in E-cadherin, due to up-regulation of the transcriptional repressor, Snail. rWnt5A treatment increases Snail and vimentin expression, and decreases E-cadherin, even in the presence of dominant-negativeTCF4, suggesting that this activation is independent of Wnt/β-catenin signaling. Because Wnt5A can signal via protein kinase C (PKC), the role of PKC in Wnt5A-mediated motility and EMT was also assessed using PKC inhibition and activation studies. Treating cells expressing low levels of Wnt5A with phorbol ester increased Snail expression inhibiting PKC in cells expressing high levels of Wnt5A decreased Snail. Furthermore, inhibition of PKC before Wnt5A treatment blocked Snail expression, implying that Wnt5A can potentiate melanoma metastasis via the induction of EMT in a PKC-dependent manner. PMID:17426020

Diguanylate Cyclase Null Mutant Reveals That C-Di-GMP Pathway Regulates the Motility and Adherence of the Extremophile Bacterium Acidithiobacillus caldus

PubMed Central

Castro, Matías; Deane, Shelly M.; Ruiz, Lina; Rawlings, Douglas E.; Guiliani, Nicolas

2015-01-01

An understanding of biofilm formation is relevant to the design of biological strategies to improve the efficiency of the bioleaching process and to prevent environmental damages caused by acid mine/rock drainage. For this reason, our laboratory is focused on the characterization of the molecular mechanisms involved in biofilm formation in different biomining bacteria. In many bacteria, the intracellular levels of c-di-GMP molecules regulate the transition from the motile planktonic state to sessile community-based behaviors, such as biofilm development, through different kinds of effectors. Thus, we recently started a study of the c-di-GMP pathway in several biomining bacteria including Acidithiobacillus caldus. C-di-GMP molecules are synthesized by diguanylate cyclases (DGCs) and degraded by phosphodiesterases (PDEs). We previously reported the existence of intermediates involved in c-di-GMP pathway from different Acidithiobacillus species. Here, we report our work related to At. caldus ATCC 51756. We identified several putative-ORFs encoding DGC and PDE and effector proteins. By using total RNA extracted from At. caldus cells and RT-PCR, we demonstrated that these genes are expressed. We also demonstrated the presence of c-di-GMP by mass spectrometry and showed that genes for several of the DGC enzymes were functional by heterologous genetic complementation in Salmonella enterica serovar Typhimurium mutants. Moreover, we developed a DGC defective mutant strain (Δc1319) that strongly indicated that the c-di-GMP pathway regulates the swarming motility and adherence to sulfur surfaces by At. caldus. Together, our results revealed that At. caldus possesses a functional c-di-GMP pathway which could be significant for ores colonization during the bioleaching process. PMID:25689133

A randomized double-blind placebo-controlled crossover-style trial of buspirone in functional dysphagia and ineffective esophageal motility.

PubMed

Aggarwal, Nitin; Thota, Prashanthi Nagavenkata; Lopez, Rocio; Gabbard, Scott

2018-02-01

Studies suggest that Ineffective Esophageal Motility (IEM) is the manometric correlate of Functional Dysphagia (FD). Currently, there is no accepted therapy for either condition. Buspirone is a serotonin modulating medication and has been shown to augment esophageal peristaltic amplitude in healthy volunteers. We aimed to determine if buspirone improves manometric parameters and symptoms in patients with overlapping IEM/FD. We performed a prospective, double-blind, placebo-controlled, crossover-style trial of 10 patients with IEM/FD. The study consisted of two 2-week treatment arms with a 2-week washout period. Outcomes measured at baseline, end of week 2, and week 6 include high resolution esophageal manometry (HREM), the Mayo Dysphagia Questionnaire-14 (MDQ-14), and the GERD-HRQL. The mean age of our 10 patients was 53 ± 9 years and 70% were female. After treatment with buspirone, 30% of patients had normalization of IEM on manometry; however, there was 30% normalization in the placebo group as well. Comparing buspirone to placebo, there was no statistically significant difference in the HREM parameters measured. There was also no statistically significant difference in symptom outcomes for buspirone compared to placebo. Of note, patients had a statistically significant decrease in the total GERD-HRQL total score when treated with placebo compared to baseline levels. Despite previous data demonstrating improved esophageal motility in healthy volunteers, our study shows no difference in terms of HREM parameters or symptom scores in IEM/FD patients treated with buspirone compared to placebo. Further research is necessary to identify novel agents for this condition. © 2017 John Wiley & Sons Ltd.

Evaluation of thyroid eye disease: quality-of-life questionnaire (TED-QOL) in Korean patients.

PubMed

Son, Byeong Jae; Lee, Sang Yeul; Yoon, Jin Sook

2014-04-01

To assess impaired quality of life (QOL) of Korean patients with thyroid eye disease (TED) using the TED-QOL questionnaire, to evaluate the adaptability of the questionnaire, and to assess the correlation between TED-QOL and scales of disease severity. Prospective, cross-sectional study. Total of 90 consecutive adult patients with TED and Graves' disease were included in this study. TED-QOL was translated into Korean and administered to the patients. The results were compared with clinical severity scores (clinical activity score, VISA (vision loss (optic neuropathy); inflammation; strabismus/motility; appearance/exposure) classification, modified NOSPECS (no signs or symptoms; only signs; soft tissue; proptosis; extraocular muscle; cornea; sight loss) score, Gorman diplopia scale, and European Group of Graves' Orbitopathy Classification). Clinical scores indicating inflammation and strabismus in patients with TED were positively correlated with overall and visual function-related QOL (Spearman coefficient 0.21-0.38, p < 0.05). Clinical scores associated with appearance were positively correlated with appearance-related QOL (Spearman coefficient 0.26-0.27, p < 0.05). In multivariate analysis, age, soft-tissue inflammation, motility disorder of modified NOSPECS, and motility disorder of VISA classification had positive correlation with overall and function-related QOL. Sex, soft-tissue inflammation, proptosis of modified NOSPECS, and appearance of VISA classification had correlation with appearance-related QOL. In addition, validity of TED-QOL was proved sufficient based on the outcomes of patient interviews and correlation between the subscales of TED-QOL. TED-QOL showed significant correlations with various objective clinical parameters of TED. TED-QOL was a simple and useful tool for rapid evaluation of QOL in daily outpatient clinics, which could be readily translated into different languages to be widely applicable to various populations. Copyright © 2014 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

NOX5 in Human Spermatozoa

PubMed Central

Musset, Boris; Clark, Robert A.; DeCoursey, Thomas E.; Petheo, Gabor L.; Geiszt, Miklos; Chen, Yumin; Cornell, John E.; Eddy, Carlton A.; Brzyski, Robert G.; El Jamali, Amina

2012-01-01

Physiological and pathological processes in spermatozoa involve the production of reactive oxygen species (ROS), but the identity of the ROS-producing enzyme system(s) remains a matter of speculation. We provide the first evidence that NOX5 NADPH oxidase is expressed and functions in human spermatozoa. Immunofluorescence microscopy detected NOX5 protein in both the flagella/neck region and the acrosome. Functionally, spermatozoa exposed to calcium ionophore, phorbol ester, or H2O2 exhibited superoxide anion production, which was blocked by addition of superoxide dismutase, a Ca2+ chelator, or inhibitors of either flavoprotein oxidases (diphenylene iododonium) or NOX enzymes (GKT136901). Consistent with our previous overexpression studies, we found that H2O2-induced superoxide production by primary sperm cells was mediated by the non-receptor tyrosine kinase c-Abl. Moreover, the HV1 proton channel, which was recently implicated in spermatozoa motility, was required for optimal superoxide production by spermatozoa. Immunoprecipitation experiments suggested an interaction among NOX5, c-Abl, and HV1. H2O2 treatment increased the proportion of motile sperm in a NOX5-dependent manner. Statistical analyses showed a pH-dependent correlation between superoxide production and enhanced sperm motility. Collectively, our findings show that NOX5 is a major source of ROS in human spermatozoa and indicate a role for NOX5-dependent ROS generation in human spermatozoa motility. PMID:22291013

Elevated aminopeptidase N affects sperm motility and early embryo development

PubMed Central

Ryu, Do-Yeal; Kwon, Woo-Sung

2017-01-01

Aminopeptidase N (APN) is a naturally occurring ectopeptidase present in mammalian semen. Previous studies have demonstrated that APN adversely affects male fertility through the alteration of sperm motility. This enzyme constitutes 0.5 to 1% of the seminal plasma proteins, which can be transferred from the prostasomes to sperms by a fusion process. In the present study, we investigated the molecular mechanism of action of APN and its role in regulating sperm functions and male fertility. In this in vitro study, epididymal mouse spermatozoa were incubated in a capacitating media (pH 7) containing 20 ng/mL of recombinant mouse APN for 90 min. Our results demonstrated that the supplementation of recombinant APN in sperm culture medium significantly increased APN activity, and subsequently altered motility, hyperactivated motility, rapid and medium swimming speeds, viability, and the acrosome reaction of mouse spermatozoa. These effects were potentially caused by increased toxicity in the spermatozoa. Further, altered APN activity in sperm culture medium affected early embryonic development. Interestingly, the effect of elevated APN activity in sperm culture medium was independent of protein tyrosine phosphorylation and protein kinase A activity. On the basis of these results, we concluded that APN plays a significant role in the regulation of several sperm functions and early embryonic development. In addition, increased APN activity could potentially lead to several adverse consequences related to male fertility. PMID:28859152

2-Heptyl-4-Quinolone, a Precursor of the Pseudomonas Quinolone Signal Molecule, Modulates Swarming Motility in Pseudomonas aeruginosa▿

PubMed Central

Ha, Dae-Gon; Merritt, Judith H.; Hampton, Thomas H.; Hodgkinson, James T.; Janecek, Matej; Spring, David R.; Welch, Martin; O'Toole, George A.

2011-01-01

Pseudomonas aeruginosa is an opportunistic pathogen capable of group behaviors, including biofilm formation and swarming motility. These group behaviors are regulated by both the intracellular signaling molecule c-di-GMP and acylhomoserine lactone quorum-sensing systems. Here, we show that the Pseudomonas quinolone signal (PQS) system also contributes to the regulation of swarming motility. Specifically, our data indicate that 2-heptyl-4-quinolone (HHQ), a precursor of PQS, likely induces the production of the phenazine-1-carboxylic acid (PCA), which in turn acts via an as-yet-unknown downstream mechanism to repress swarming motility. We show that this HHQ- and PCA-dependent swarming repression is apparently independent of changes in global levels of c-di-GMP, suggesting complex regulation of this group behavior. PMID:21965567

Control of actin-based motility through localized actin binding

PubMed Central

Banigan, Edward J.; Lee, Kun-Chun; Liu, Andrea J.

2014-01-01

A wide variety of cell biological and biomimetic systems use actin polymerization to drive motility. It has been suggested that an object such as a bacterium can propel itself by self-assembling a high concentration of actin behind it if it is repelled by actin. However, it is also known that it is essential for the moving object to bind actin. Therefore, a key question is how the actin tail can propel an object when it both binds and repels the object. We present a physically consistent Brownian dynamics model for actin-based motility that includes the minimal components of the dendritic nucleation model and allows for both attractive and repulsive interactions between actin and a moveable disk. We find that the concentration gradient of filamentous actin generated by polymerization is sufficient to propel the object, even with moderately strong binding interactions. Additionally, actin binding can act as a biophysical cap, and may directly control motility through modulation of network growth. Overall, this mechanism is robust in that it can drive motility against a load up to a stall pressure that depends on the Young’s modulus of the actin network and can explain several aspects of actin-based motility. PMID:24225232

The effect of Daikenchuto on postoperative intestinal motility in patients with right-side colon cancer.

PubMed

Yamada, Takeshi; Matsumoto, Satoshi; Matsuda, Michihiro Koizumi Akihisa; Shinji, Seiichi; Yokoyama, Yasuyuki; Takahashi, Goro; Iwai, Takuma; Takeda, Kouki; Ohta, Keiichiro; Uchida, Eiji

2017-07-01

Daikenchuto (DKT) has a stimulant effect on intestinal motility and reportedly has a positive effect on postoperative intestinal motility in patients with sigmoid colon cancer. In this study, we investigated the effects of DKT in patients with right-side colon cancer. This retrospective study included 88 patients with right-side colon cancer. We orally administered 7.5 g of DKT in the DKT group and did not administer any DKT to patients in the no-DKT group. All patients ingested radiopaque markers 2 h before surgery, which were used to assess intestinal motility. The postoperative intestinal motility was radiologically assessed by counting the numbers of residual markers in the large and small intestines. The DKT and no-DKT groups showed no marked differences in the total number of residual markers or number of residual markers in the small intestine. However, in the elderly subgroup, the total number of residual markers in the DKT group was significantly less than in the no-DKT group. Although DKT had some small effect on the postoperative intestinal motility for most patients, it may have positive effects in elderly patients.

Swimming motility plays a key role in the stochastic dynamics of cell clumping

NASA Astrophysics Data System (ADS)

Qi, Xianghong; Nellas, Ricky B.; Byrn, Matthew W.; Russell, Matthew H.; Bible, Amber N.; Alexandre, Gladys; Shen, Tongye

2013-04-01

Dynamic cell-to-cell interactions are a prerequisite to many biological processes, including development and biofilm formation. Flagellum induced motility has been shown to modulate the initial cell-cell or cell-surface interaction and to contribute to the emergence of macroscopic patterns. While the role of swimming motility in surface colonization has been analyzed in some detail, a quantitative physical analysis of transient interactions between motile cells is lacking. We examined the Brownian dynamics of swimming cells in a crowded environment using a model of motorized adhesive tandem particles. Focusing on the motility and geometry of an exemplary motile bacterium Azospirillum brasilense, which is capable of transient cell-cell association (clumping), we constructed a physical model with proper parameters for the computer simulation of the clumping dynamics. By modulating mechanical interaction (‘stickiness’) between cells and swimming speed, we investigated how equilibrium and active features affect the clumping dynamics. We found that the modulation of active motion is required for the initial aggregation of cells to occur at a realistic time scale. Slowing down the rotation of flagellar motors (and thus swimming speeds) is correlated to the degree of clumping, which is consistent with the experimental results obtained for A. brasilense.

Flagellin glycosylation with pseudaminic acid in Campylobacter and Helicobacter: prospects for development of novel therapeutics.

PubMed

Salah Ud-Din, Abu Iftiaf Md; Roujeinikova, Anna

2018-04-01

Many pathogenic bacteria require flagella-mediated motility to colonise and persist in their hosts. Helicobacter pylori and Campylobacter jejuni are flagellated epsilonproteobacteria associated with several human pathologies, including gastritis, acute diarrhea, gastric carcinoma and neurological disorders. In both species, glycosylation of flagellin with an unusual sugar pseudaminic acid (Pse) plays a crucial role in the biosynthesis of functional flagella, and thereby in bacterial motility and pathogenesis. Pse is found only in pathogenic bacteria. Its biosynthesis via six consecutive enzymatic steps has been extensively studied in H. pylori and C. jejuni. This review highlights the importance of flagella glycosylation and details structural insights into the enzymes in the Pse pathway obtained via a combination of biochemical, crystallographic, and mutagenesis studies of the enzyme-substrate and -inhibitor complexes. It is anticipated that understanding the underlying structural and molecular basis of the catalytic mechanisms of the Pse-synthesising enzymes will pave the way for the development of novel antimicrobials.

Physcomitrella MADS-box genes regulate water supply and sperm movement for fertilization.

PubMed

Koshimizu, Shizuka; Kofuji, Rumiko; Sasaki-Sekimoto, Yuko; Kikkawa, Masahide; Shimojima, Mie; Ohta, Hiroyuki; Shigenobu, Shuji; Kabeya, Yukiko; Hiwatashi, Yuji; Tamada, Yosuke; Murata, Takashi; Hasebe, Mitsuyasu

2018-01-01

MIKC classic (MIKC C )-type MADS-box genes encode transcription factors that function in various developmental processes, including angiosperm floral organ identity. Phylogenetic analyses of the MIKC C -type MADS-box family, including genes from non-flowering plants, suggest that the increased numbers of these genes in flowering plants is related to their functional divergence; however, their precise functions in non-flowering plants and their evolution throughout land plant diversification are unknown. Here, we show that MIKC C -type MADS-box genes in the moss Physcomitrella patens function in two ways to enable fertilization. Analyses of protein localization, deletion mutants and overexpression lines of all six genes indicate that three MIKC C -type MADS-box genes redundantly regulate cell division and growth in the stems for appropriate external water conduction, as well as the formation of sperm with motile flagella. The former function appears to be maintained in the flowering plant lineage, while the latter was lost in accordance with the loss of sperm.

Active matter model of Myxococcus xanthus aggregation

NASA Astrophysics Data System (ADS)

Patch, Adam; Bahar, Fatmagul; Liu, Guannan; Thutupalli, Shashi; Welch, Roy; Yllanes, David; Shaevitz, Joshua; Marchetti, M. Cristina

Myxococcus xanthus is a soil-dwelling bacterium that exhibits several fascinating collective behaviors including streaming, swarming, and generation of fruiting bodies. A striking feature of M. xanthus is that it periodically reverses its motility direction. The first stage of fruiting body formation is characterized by the aggregation of cells on a surface into round mesoscopic structures. Experiments have shown that this aggregation relies heavily on regulation of the reversal rate and local mechanical interactions, suggesting motility-induced phase separation may play an important role. We have adapted self-propelled particle models to include cell reversal and motility suppression resulting from sporulation observed in aggregates. Using 2D molecular dynamics simulations, we map the phase behavior in the space of Péclet number and local density and examine the kinetics of aggregation for comparison to experiments.

Group X secreted phospholipase A₂ specifically decreases sperm motility in mice.

PubMed

Escoffier, Jessica; Pierre, Virginie J; Jemel, Ikram; Munch, Léa; Boudhraa, Zied; Ray, Pierre F; De Waard, Michel; Lambeau, Gérard; Arnoult, Christophe

2011-10-01

Different mammalian secreted phospholipases A(2) (sPLA(2) s) are expressed in male reproductive organs and/or in sperm cells but their cellular functions are still not fully characterized. Because several reports indicate a link between cellular lipids and sperm motility, we have investigated the effect of mouse group IIA, IID, IIE, V, and X sPLA(2) s on sperm motility. Among these enzymes, only mouse group X sPLA(2) (mGX sPLA(2) ) acts as a potent inhibitor of sperm motility that decreases track speed (VCL) and lateral displacement of the head (ALH) of both noncapacitated and capacitated sperm. The inhibitory effect of mGX sPLA(2) is dependent on its enzymatic activity because (i) both the proenzyme form of mGX sPLA(2) (pro-mGX) and the H48Q mutant of mGX sPLA(2) have very weak enzymatic activity and are unable to modulate sperm motility and (ii) LY329722, a specific inhibitor of sPLA(2) s, blocks the inhibitory effect of mGX sPLA(2) . Moreover, mGX sPLA(2) exerts a gradual potency on sperm subpopulations with different velocities, an effect which may be linked to the heterogeneity of lipid composition in these sperm subpopulations. Finally, we found that endogenous mGX sPLA(2) released during spontaneous acrosome reaction modulates sperm motility of capacitated sperm. Together, our results suggest a new role of sPLA(2) in sperm physiology where the sPLA2 selects a sperm subpopulation for fertilization based on its effect on sperm motility. Copyright © 2010 Wiley-Liss, Inc.

Dog Sperm Cryopreservation in Glucose-Fructose or Sucrose Supplemented Glycerol-Free Tris: Effect of Post-Thaw Incubation Time on Gene Expression Related to Apoptosis and Motility.

PubMed

Rahman, M A; Park, S H; Yu, I J

　　OBJECTIVE: The study evaluated the effects of glucose-fructose or sucrose supplementation in glycerol-free Tris (GFT) solution on motility, viability, the level of reactive oxygen species (ROS), as well as the level of apoptosis (BAX and BCL2) and motility (SMCP)-related gene expression of dog spermatozoa. Spermatozoa (5×10 7 sperm/ml) were cryopreserved in GFT containing 86 mM glucose and 86 mM fructose (GF-GFT) or 100 mM sucrose (S-GFT). Progressive motility, viability, ROS (H 2 O 2 ) level and mRNA gene expression of spermatozoa were evaluated 0 h, 3 h or 6 h post-thaw at 24°C. The motility of spermatozoa cryopreserved in GF-GFT was increased throughout the post-thaw incubation time. The motility of spermatozoa cryopreserved in S-GFT was increased at 3 h of post-thaw incubation. The sperm ROS level in the GF-GFT group was inconsistent during the post-thaw incubation time; however, the ROS level in the S-GFT group was gradually increased with progression of the post-thaw incubation period. The post-thaw incubation had no substantial effect on the mRNA expression of the BAX, BCL2, and SMCP genes of spermatozoa in both the GF-GFT and S-GFT groups. The supplementation of glucose and fructose improves progressive sperm motility during 6 h of post-thaw incubation while maintaining similar sperm viability. The addition of GF to GFT for cryopreservation and post-thaw incubation would yield more functional spermatozoa for future assisted reproduction practices.

Different patterns of metabolic cryo-damage in domestic cat (Felis catus) and cheetah (Acinonyx jubatus) spermatozoa.

PubMed

Terrell, Kimberly A; Wildt, David E; Anthony, Nicola M; Bavister, Barry D; Leibo, S P; Penfold, Linda M; Marker, Laurie L; Crosier, Adrienne E

2012-04-01

Felid spermatozoa are sensitive to cryopreservation-induced damage, but functional losses can be mitigated by post-thaw swim-up or density gradient processing methods that selectively recover motile or structurally-normal spermatozoa, respectively. Despite the importance of sperm energy production to achieving fertilization, there is little knowledge about the influence of cryopreservation or post-thaw processing on felid sperm metabolism. We conducted a comparative study of domestic cat and cheetah sperm metabolism after cryopreservation and post-thaw processing. We hypothesized that freezing/thawing impairs sperm metabolism and that swim-up, but not density gradient centrifugation, recovers metabolically-normal spermatozoa. Ejaculates were cryopreserved, thawed, and processed by swim-up, Accudenz gradient centrifugation, or conventional washing (representing the 'control'). Sperm glucose and pyruvate uptake, lactate production, motility, and acrosomal integrity were assessed. Mitochondrial membrane potential (MMP) was measured in cat spermatozoa. In both species, lactate production, motility, and acrosomal integrity were reduced in post-thaw, washed samples compared to freshly-collected ejaculates. Glucose uptake was minimal pre- and post-cryopreservation, whereas pyruvate uptake was similar between treatments due to high coefficients of variation. In the cat, swim-up, but not Accudenz processing, recovered spermatozoa with increased lactate production, pyruvate uptake, and motility compared to controls. Although confounded by differences in non-specific fluorescence among processing methods, MMP values within treatments were positively correlated to sperm motility and acrosomal integrity. Cheetah spermatozoa isolated by either selection method exhibited improved motility and/or acrosomal integrity, but remained metabolically compromised. Collectively, findings revealed a metabolically-robust subpopulation of cryopreserved cat, but not cheetah, spermatozoa, recovered by selecting for motility rather than morphology. Published by Elsevier Inc.

Drug marker absorption in relation to pellet size, gastric motility and viscous meals in humans

NASA Technical Reports Server (NTRS)

Rhie, J. K.; Hayashi, Y.; Welage, L. S.; Frens, J.; Wald, R. J.; Barnett, J. L.; Amidon, G. E.; Putcha, L.; Amidon, G. L.

1998-01-01

PURPOSE: The objective of this study was to evaluate drug marker absorption in relation to the gastric emptying (GE) of 0.7 mm and 3.6 mm enteric coated pellets as a function of viscosity and the underlying gastric motility. METHODS: Twelve subjects were evaluated in a 3-way crossover study. 0.7 mm caffeine and 3.6 mm acetaminophen enteric coated pellets were concurrently administered with a viscous caloric meal at the levels of 4000, 6000 and 8000 cP. Gastric motility was simultaneously measured with antral manometry and compared to time events in the plasma profiles of the drug markers. RESULTS: Caffeine, from the 0.7 mm pellets, was observed significantly earlier in the plasma than acetaminophen, from the 3.6 mm pellets, at all levels of viscosity. Motility related size differentiated GE was consistently observed at all viscosity levels, however, less variability was observed with the 4000 cP meal. Specifically, the onset of absorption from the of 3.6 mm pellets correlated with the onset of Phase II fasted state contractions (r = 0.929, p < 0.01). CONCLUSIONS: The timeframe of drug marker absorption and the onset of motility events were not altered within the range of viscosities evaluated. Rather, the differences in drug marker profiles from the non-digestible solids were most likely the result of the interaction between viscosity and motility influencing antral flow dynamics. The administration of the two sizes of pellets and a viscous caloric meal with subsequent monitoring of drug marker profiles is useful as a reference to assess the influence of motility patterns on the absorption profile of orally administered agents.

Effects of hydrogen sulphide on motility patterns in the rat colon

PubMed Central

Gil, V; Parsons, SP; Gallego, D; Huizinga, JD; Jimenez, M

2013-01-01

Background and Purpose Hydrogen sulphide (H2S) is an endogenous gaseous signalling molecule with putative functions in gastrointestinal motility regulation. Characterization of H2S effects on colonic motility is crucial to establish its potential use as therapeutic agent in the treatment of colonic disorders. Experimental Approach H2S effects on colonic motility were characterized using video recordings and construction of spatio-temporal maps. Microelectrode and muscle bath studies were performed to investigate the mechanisms underlying H2S effects. NaHS was used as the source of H2S. Key Results Rhythmic propulsive motor complexes (RPMCs) and ripples were observed in colonic spatio-temporal maps. Serosal addition of NaHS concentration-dependently inhibited RPMCs. In contrast, NaHS increased amplitude of the ripples without changing their frequency. Therefore, ripples became the predominant motor pattern. Neuronal blockade with lidocaine inhibited RPMCs, which were restored after administration of carbachol. Subsequent addition of NaHS inhibited RPMCs. Luminal addition of NaHS did not modify motility patterns. NaHS inhibited cholinergic excitatory junction potentials, carbachol-induced contractions and hyperpolarized smooth muscle cells, but did not modify slow wave activity. Conclusions and Implications H2S modulated colonic motility inhibiting propulsive contractile activity and enhancing the amplitude of ripples, promoting mixing. Muscle hyperpolarization and inhibition of neurally mediated cholinergic responses contributed to the inhibitory effect on propulsive activity. H2S effects were not related to changes in the frequency of slow wave activity originating in the network of interstitial cells of Cajal located near the submuscular plexus. Luminal H2S did not modify colonic motility probably because of epithelial detoxification. PMID:23297830

Nanofluid slip flow over a stretching cylinder with Schmidt and Péclet number effects

NASA Astrophysics Data System (ADS)

Md Basir, Md Faisal; Uddin, M. J.; Md. Ismail, A. I.; Bég, O. Anwar

2016-05-01

A mathematical model is presented for three-dimensional unsteady boundary layer slip flow of Newtonian nanofluids containing gyrotactic microorganisms over a stretching cylinder. Both hydrodynamic and thermal slips are included. By applying suitable similarity transformations, the governing equations are transformed into a set of nonlinear ordinary differential equations with appropriate boundary conditions. The transformed nonlinear ordinary differential boundary value problem is then solved using the Runge-Kutta-Fehlberg fourth-fifth order numerical method in Maple 18 symbolic software. The effects of the controlling parameters on the dimensionless velocity, temperature, nanoparticle volume fractions and microorganism motile density functions have been illustrated graphically. Comparisons of the present paper with the existing published results indicate good agreement and supports the validity and the accuracy of our numerical computations. Increasing bioconvection Schmidt number is observed to depress motile micro-organism density function. Increasing thermal slip parameter leads to a decrease in temperature. Thermal slip also exerts a strong influence on nano-particle concentration. The flow is accelerated with positive unsteadiness parameter (accelerating cylinder) and temperature and micro-organism density function are also increased. However nano-particle concentration is reduced with positive unsteadiness parameter. Increasing hydrodynamic slip is observed to boost temperatures and micro-organism density whereas it decelerates the flow and reduces nano-particle concentrations. The study is relevant to nano-biopolymer manufacturing processes.

Effect of semen extender and storage temperature on ram sperm motility over time

USDA-ARS?s Scientific Manuscript database

Storage of ram semen for long period of time depends on a number of factors, including type of extender and storage temperature. A study compared the effect of semen extender and storage temperature on motility of ram semen stored for 72 h. Semen collected via electroejaculator from 5 mature Katahd...

The effect of antibiotics on swimming and swarming motility of multidrug-resistant Salmonella enterica serovar Typhimurium

USDA-ARS?s Scientific Manuscript database

Motile bacteria can employ one or more different strategies to move, including swimming, swarming, twitching, gliding, sliding, and darting. Swimming is considered the movement of individual bacteria through a liquid or semi-solid medium, while swarming is the concerted movement of a group of bacte...

Retained functional integrity of bull spermatozoa after double freezing and thawing using PureSperm density gradient centrifugation.

PubMed

Maxwell, W M C; Parrilla, I; Caballero, I; Garcia, E; Roca, J; Martinez, E A; Vazquez, J M; Rath, D

2007-10-01

The main aim of this study was to compare the motility and functional integrity of bull spermatozoa after single and double freezing and thawing. The viability and morphological integrity of spermatozoa selected by PureSperm density gradient centrifugation after cryopreservation of bovine semen in two commercial extenders (Experiment 1) and the function of bull spermatozoa before and after a second freezing and thawing assisted by PureSperm selection (Experiment 2) were examined. On average, 35.8 +/- 12.1% of sperm loaded onto the PureSperm density gradient were recovered after centrifugation. In Experiment 1, post-thaw motility and acrosome integrity were higher for spermatozoa frozen in Tris-egg yolk extender than in AndroMed, whether the assessments were made immediately after thawing [80.4 +/- 12.7 vs 47.6 +/- 19.0% motile and 78.8 +/- 8.3 vs 50.1 +/- 19.5% normal apical ridge (NAR), p < 0.05] or after preparation on the gradient (83.3 +/- 8.6 vs 69.4 +/- 15.9% motile and 89.5 +/- 7.2 vs 69.1 +/- 11.4% NAR, p < 0.05). For semen frozen in Tris-egg yolk extender, selection on the PureSperm gradient did not influence total motility but significantly improved the proportion of acrosome-intact spermatozoa. After the gradient, both the total motility and percentage of normal acrosomes increased for spermatozoa frozen in AndroMed (Minitüb Tiefenbach, Germany). In Experiment 2, there was no difference in sperm motility after the first and second freeze-thawing (82.9 +/- 12.7 vs 68.8 +/- 18.7%). However, the proportion of acrosome-intact spermatozoa was significantly improved by selection through the PureSperm gradient, whether measured by phase contrast microscopy (78.9 +/- 9.7 vs 90.4 +/- 4.0% NAR, p < 0.05) or flow cytometry (53.4 +/- 11.7 vs 76.3 +/- 6.0% viable acrosome-intact spermatozoa, p < 0.001). The improvement in the percentage of spermatozoa with normal acrosomes was maintained after resuspension in the cooling extender and cooling to 4 degrees C (88.2 +/- 6.2) and after re-freezing and thawing (83.6 +/- 6.56% NAR). However, flow cytometric assessment of the sperm membranes revealed a decline in the percentage of viable spermatozoa with intact membranes after the second freezing and thawing compared with after gradient centrifugation (76.3 +/- 6.0% vs 46.6 +/- 6.6%, p < 0.001) to levels equivalent to those obtained after the first round of freeze-thawing (53.4 +/- 11.7% viable acrosome-intact spermatozoa). Sperm movement characteristics assessed by computer-assisted analysis were unaffected in the population selected on the PureSperm gradients but declined after cooling of the selected and extended spermatozoa to 4 degrees C. There was no further change in these kinematic measurements after the cooled spermatozoa had undergone the second round of freeze-thawing. These results demonstrate that bull semen can be frozen and thawed, followed by a second freeze-thawing cycle of a population of spermatozoa selected by PureSperm, with retained motility and functional integrity. This points to the possibility of using double frozen spermatozoa in bovine artificial insemination programmes and to the potential benefits of PureSperm density gradient centrifugation for the application of cryopreserved bull spermatozoa to other biotechnological procedures such as flow cytometric sex sorting followed by re-freezing and thawing.

Function and culture requirements of snow leopard (Panthera uncia) spermatozoa in vitro.

PubMed

Roth, T L; Howard, J G; Donoghue, A M; Swanson, W F; Wildt, D E

1994-08-01

Electroejaculates from eight snow leopards were used to determine how the motility of spermatozoa was influenced by (i) type of media (Ham's F10, PBS, human tubal fluid or RPMI-1640); (ii) holding temperature (23 degrees C versus 37 degrees C); (iii) washing of spermatozoa and (iv) a sperm metabolic enhancer, pentoxifylline. The duration of sperm motility was assessed by evaluating samples in each treatment every hour for 6 h and a sperm motility index (a value combining percentage sperm motility and rate of forward progression) calculated. Spermatozoa from the Ham's F10, PBS and PBS plus pentoxifylline treatments were also co-incubated with zona-intact, domestic cat eggs that were fixed and evaluated for spermatozoa bound to the zona pellucida, penetrating the outer and inner layers of the zona pellucida and within the perivitelline space. During the 6 h co-incubation, the sperm motility index in PBS with pentoxifylline was greater (P < 0.05) than in PBS alone which, in turn, was greater (P < 0.05) than in the other three test media. Washing the spermatozoa enhanced (P < 0.05) motility in both PBS and PBS plus pentoxifylline relative to unwashed samples, but there was no effect (P > 0.05) of holding temperature. Pentoxifylline supplementation enhanced (P < 0.05) the proportion of cat eggs with bound, but not penetrated, snow leopard spermatozoa in the inner layer of the zona pellucida, and there were no spermatozoa in the perivitelline space.(ABSTRACT TRUNCATED AT 250 WORDS)

Evolution and Diversity of the Ras Superfamily of Small GTPases in Prokaryotes

PubMed Central

Wuichet, Kristin; Søgaard-Andersen, Lotte

2015-01-01

The Ras superfamily of small GTPases are single domain nucleotide-dependent molecular switches that act as highly tuned regulators of complex signal transduction pathways. Originally identified in eukaryotes for their roles in fundamental cellular processes including proliferation, motility, polarity, nuclear transport, and vesicle transport, recent studies have revealed that single domain GTPases also control complex functions such as cell polarity, motility, predation, development and antibiotic resistance in bacteria. Here, we used a computational genomics approach to understand the abundance, diversity, and evolution of small GTPases in prokaryotes. We collected 520 small GTPase sequences present in 17% of 1,611 prokaryotic genomes analyzed that cover diverse lineages. We identified two discrete families of small GTPases in prokaryotes that show evidence of three distinct catalytic mechanisms. The MglA family includes MglA homologs, which are typically associated with the MglB GTPase activating protein, whereas members of the Rup (Ras superfamily GTPase of unknown function in prokaryotes) family are not predicted to interact with MglB homologs. System classification and genome context analyses support the involvement of small GTPases in diverse prokaryotic signal transduction pathways including two component systems, laying the foundation for future experimental characterization of these proteins. Phylogenetic analysis of prokaryotic and eukaryotic GTPases supports that the last universal common ancestor contained ancestral MglA and Rup family members. We propose that the MglA family was lost from the ancestral eukaryote and that the Ras superfamily members in extant eukaryotes are the result of vertical and horizontal gene transfer events of ancestral Rup GTPases. PMID:25480683

CRISPR/Cas9 mediated sequential editing of genes critical for ookinete motility in Plasmodium yoelii.

PubMed

Zhang, Cui; Gao, Han; Yang, Zhenke; Jiang, Yuanyuan; Li, Zhenkui; Wang, Xu; Xiao, Bo; Su, Xin-Zhuan; Cui, Huiting; Yuan, Jing

2017-03-01

CRISPR/Cas9 has been successfully adapted for gene editing in malaria parasites including Plasmodium falciparum and Plasmodium yoelii. However, the reported methods were limited to editing one gene at a time. In practice, it is often desired to modify multiple genetic loci in a parasite genome. Here we describe a CRISPR/Cas9 mediated genome editing method that allows successive modification of more than one gene in the genome of P. yoelii using an improved single-vector system (pYCm) we developed previously. Drug resistant genes encoding human dihydrofolate reductase (hDHFR) and a yeast bifunctional protein (yFCU), with cytosine deaminase (CD) and uridyl phosphoribosyl transferase (UPRT) activities in the plasmid, allowed sequential positive (pyrimethamine, Pyr) and negative (5-fluorocytosine, 5FC) selections and generation of transgenic parasites free of the episomal plasmid after genetic modification. Using this system, we were able to efficiently tag a gene of interest (Pyp28) and subsequently disrupted two genes (Pyctrp and Pycdpk3) that are individually critical for ookinete motility. Disruption of the genes either eliminated (Pyctrp) or greatly reduced (Pycdpk3) ookinete forward motility in matrigel in vitro and completely blocked oocyst development in mosquito midgut. The method will greatly facilitate studies of parasite gene function, development, and disease pathogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

Oxygen-Dependent Globin Coupled Sensor Signaling Modulates Motility and Virulence of the Plant Pathogen Pectobacterium carotovorum.

PubMed

Burns, Justin L; Jariwala, Parth B; Rivera, Shannon; Fontaine, Benjamin M; Briggs, Laura; Weinert, Emily E

2017-08-18

Bacterial pathogens utilize numerous signals to identify the presence of their host and coordinate changes in gene expression that allow for infection. Within plant pathogens, these signals typically include small molecules and/or proteins from their plant hosts and bacterial quorum sensing molecules to ensure sufficient bacterial cell density for successful infection. In addition, bacteria use environmental signals to identify conditions when the host defenses are weakened and potentially to signal entry into an appropriate host/niche for infection. A globin coupled sensor protein (GCS), termed PccGCS, within the soft rot bacterium Pectobacterium carotovorum ssp. carotovorum WPP14 has been identified as an O 2 sensor and demonstrated to alter virulence factor excretion and control motility, with deletion of PccGCS resulting in decreased rotting of a potato host. Using small molecules that modulate bacterial growth and quorum sensing, PccGCS signaling also has been shown to modulate quorum sensing pathways, resulting in the PccGCS deletion strain being more sensitive to plant-derived phenolic acids, which can function as quorum sensing inhibitors, and exhibiting increased N-acylhomoserine lactone (AHL) production. These findings highlight a role for GCS proteins in controlling key O 2 -dependent phenotypes of pathogenic bacteria and suggest that modulating GCS signaling to limit P. carotovorum motility may provide a means to decrease rotting of plant hosts.

A Conservative Amino Acid Mutation in the Master Regulator FleQ Renders Pseudomonas aeruginosa Aflagellate

PubMed Central

Jain, Ruchi; Kazmierczak, Barbara I.

2014-01-01

Flagellar-based motility plays a critical role in Pseudomonas aeruginosa pathogenesis, influencing both the establishment of bacterial infection and the host's response to the pathogen. Nonetheless, aflagellate clinical strains are often isolated from acutely and chronically infected patients and include the virulent laboratory strain PA103. We determined that PA103's aflagellate phenotype is the result of a single amino acid change (G240V) in the master flagellar regulator, FleQ. This mutation, which lies just outside the Walker B box of FleQ, abrogates the ability of FleQ to positively regulate flagellar gene expression. Reversal of this seemingly conservative amino acid substitution is sufficient to restore swimming motility to PA103, despite the presence of mutations in other flagellar genes of PA103. We also investigated the consequences of restoring flagellar assembly on PA103 virulence. Although a negative correlation between flagellar assembly and Type 3 secretion system (T3SS) expression has been reported previously, we did not observe downregulation of T3SS expression or function in Fla+ PA103. Restoration of flagellar assembly did, however, amplify IL-1 signals measured during murine pulmonary infection and was associated with increased bacterial clearance. These experiments suggest that loss of flagellar motility may primarily benefit PA103 by attenuating pathogen recognition and clearance during acute infection. PMID:24827992

Gab2 Phosphorylation by RSK Inhibits Shp2 Recruitment and Cell Motility

PubMed Central

Zhang, Xiaocui; Lavoie, Genevieve; Fort, Loic; Huttlin, Edward L.; Tcherkezian, Joseph; Galan, Jacob A.; Gu, Haihua; Gygi, Steven P.; Carreno, Sebastien

2013-01-01

The scaffolding adapter protein Gab2 (Grb2-associated binder) participates in the signaling response evoked by various growth factors and cytokines. Gab2 is overexpressed in several human malignancies, including breast cancer, and was shown to promote mammary epithelial cell migration. The role of Gab2 in the activation of different signaling pathways is well documented, but less is known regarding the feedback mechanisms responsible for its inactivation. We now demonstrate that activation of the Ras/mitogen-activated protein kinase (MAPK) pathway promotes Gab2 phosphorylation on basic consensus motifs. More specifically, we show that RSK (p90 ribosomal S6 kinase) phosphorylates Gab2 on three conserved residues, both in vivo and in vitro. Mutation of these phosphorylation sites does not alter Gab2 binding to Grb2, but instead, we show that Gab2 phosphorylation inhibits the recruitment of the tyrosine phosphatase Shp2 in response to growth factors. Expression of an unphosphorylatable Gab2 mutant in mammary epithelial cells promotes an invasion-like phenotype and increases cell motility. Taken together, these results suggest that RSK is part of a negative-feedback loop that restricts Gab2-dependent epithelial cell motility. On the basis of the widespread role of Gab2 in receptor signaling, these findings also suggest that RSK plays a regulatory function in diverse receptor systems. PMID:23401857

Constipation: evaluation and treatment of colonic and anorectal motility disorders.

PubMed

Rao, Satish S C

2007-09-01

This article focuses on the colonic and anorectal motility disturbances that are associated with chronic constipation and their management. Functional chronic constipation consists of three overlapping subtypes: slow transit constipation, dyssynergic defecation, and irritable bowel syndrome with constipation. The Rome criteria may serve as a useful guide for making a clinical diagnosis of functional constipation. Today, an evidence-based approach can be used to treat patients with chronic constipation. The availability of specific drugs for the treatment of chronic constipation, such as tegaserod and lubiprostone, has enhanced the therapeutic armamentarium for managing these patients. Randomized controlled trials have also established the efficacy of biofeedback therapy in the treatment of dyssynergic defecation.

Correlation between extraocular muscle size and motility restriction in thyroid eye disease.

PubMed

Dagi, Lora R; Zoumalan, Christopher I; Konrad, Hindola; Trokel, Stephen L; Kazim, Michael

2011-01-01

Evaluate the relationship between extraocular muscle (EOM) size, measured by computed tomography, and ocular motility in thyroid eye disease (TED). This case series is based on a retrospective review of the records of 54 patients (108 orbits) with TED. Main outcome measures included EOM size and degree of motility restriction. The average diameter of each rectus muscle was compared with published norms. Four subpopulations based on Age (< 40 or ≥ 40 years) and State of thyroid eye disease (active or stable) were studied. Versions were measured by the corneal light reflex method. The trend of muscle diameter versus motility restriction was evaluated. The average EOM diameter was greater than the norm in the study cohort and 4 subpopulations. The average diameter was largest in the Older and Active TED subpopulations. The inferior rectus and medial rectus were most frequently restricted in the study cohort and 4 subpopulations. The medial rectus had the strongest trend between increasing diameter and motility restriction, followed by the inferior rectus and the superior muscle group (comprised of the superior rectus and levator palpebrae superioris). However, there was a general lack of strong correlation between the diameter of the rectus muscles and their respective motility, especially in the Younger subpopulation. EOM diameters are larger and have more restricted motility in the Older and Active TED subpopulations. Contrary to prior publications, the correlation between EOM diameters and motility was weak, especially in the Younger subpopulation. These findings suggest that the pathophysiology of EOM enlargement is different based upon the age of the patient and the activity of the orbitopathy.

Snow leopard (Panthera uncia) spermatozoa are sensitive to alkaline pH, but motility in vitro is not influenced by protein or energy supplements.

PubMed

Roth, T L; Swanson, W F; Collins, D; Burton, M; Garell, D M; Wildt, D E

1996-01-01

To better understand the biology of snow leopard spermatozoa and to facilitate developing assisted reproduction, a series of studies was conducted to: 1) identify the component(s) of complex culture media responsible for the detrimental effect on sperm survival in vitro, 2) optimize medium for supporting sperm viability, and 3) evaluate sperm capacitation in vitro. Constituents of complex media were added systematically to phosphate-buffered saline (PBS) to isolate the factor(s) influencing snow leopard sperm motility in vitro. Sperm capacitation was also assessed following incubation in PBS with bovine serum albumin (BSA), fetal calf serum (FCS), or heparin. For maintaining sperm motility, there was no benefit (P > or = 0.05) to supplementing PBS with low (5%) or high (20%) concentrations of snow leopard serum (SLS) versus FCS or BSA. Likewise, adding supplemental energy substrates (pyruvate, glucose, lactate, or glutamine) did not enhance or hinder (P > or = 0.05) sperm motility. However, motility rapidly decreased (P < 0.05) with the addition of NaHCO3 to PBS or Ham's F10 nutrient mixture. Surprisingly, Ham's F10 with no buffering component or with both NaHCO3 and N-Z-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) maintained sperm motility at levels similar (P > or = 0.05) to PBS. Although sperm motility in all treatments decreased with time, there was a strong inverse relationship (P < 0.01; r = 0.90) between motility and sample pH at 6 hours. Spermatozoa incubated in PBS containing FCS, BSA, or heparin did not undergo the acrosome reaction when exposed to calcium ionophore. In summary, alkaline pH has a profound detrimental effect on snow leopard sperm motility, and capacitation does not occur under conditions that normally promote this event in other felid species. These results clearly demonstrate a high degree of interspecific variation among felids in fundamental sperm function, and they provide evidence for the necessity of basic research when developing assisted reproduction in little-studied nondomestic species.

Effects of female bovine plasma collected at different days of the estrous cycle on epididymal spermatozoa motility.

PubMed

Nait Mouloud, M; Ouennoughi, F; Yaiche, L; Kaidi, R; Iguer-Ouada, M

2017-03-15

The aim of this study was to assess the effects of female bovine plasma collected at different days of the reproductive cycle on epididymal spermatozoa motility and to test hypothesis that the subpopulations pattern of motile spermatozoa is affected by this treatment. Blood plasma samples were collected from five Holstein Friesian cows at different stages of the estrous cycle (days 0, 5, 10, 12 and 18), one pregnant cow and one adult bull and were diluted 1:9 (V/V) with normal saline. Female charcoal-treated plasma, Bull plasma and saline were used as controls. Semen samples were obtained from cauda epididymidis through retrograde flushing and diluted in saline to approximately 60 × 106 sperm/ml. The extended semen was diluted 1:2 (V/V) with tested media and motility was evaluated at 15 min and then every hour for 6 h using a computer-assisted semen analysis. Multivariate clustering procedure was applied to identify and quantify specific subpopulations within the semen samples. The statistical analysis clustered all the motile spermatozoa into three separate subpopulations with defined patterns of movement: Subpopulation 1 poorly motile and non-progressive spermatozoa (39.3%), subpopulation 2 including the fastest and the most vigorous spermatozoa (46.4%) and subpopulation 3 represented by slow, non-vigorous but linear spermatozoa (14.3%). Initially, sperm samples supplemented with female, male or female charcoal-treated plasma stimulated equally total motility and spermatozoa belonging to subpopulation 2 regardless of the estrous cycle stage. After 1-h incubation, the motility of these both categories of spermatozoa (total motile and those assigned to subpopulation 2) is enhanced and maintained more in day 12, 18 and pregnant cow plasma than in female plasma from earlier stage of the estrous cycle (day 0, 5 and 10), male plasma and female-charcoal treated plasma. In conclusion, the overall results showed that female plasma stimulated significantly sperm motility, especially at the late stage of the estrous cycle. Additionally, to the diverse compounds contained in blood plasma, progesterone may play a key role in such motility activation. Copyright © 2016 Elsevier Inc. All rights reserved.

Mobile phones electromagnetic radiation and NAD+-dependent isocitrate dehydrogenase as a mitochondrial marker in asthenozoospermia.

PubMed

Hagras, Abeer M; Toraih, Eman A; Fawzy, Manal S

2016-12-01

NAD + -dependent Isocitrate Dehydrogenase (NAD + -IDH) could be one of the cell phone radiation targets. Enzyme activity alteration may lead to decline in sperm motility during radio-frequency electromagnetic waves (RF-EMW) exposure. The current case control study aimed to investigate the possible relationship between mitochondrial NAD + -IDH activity in human seminal plasma and sperm motility among asthenozoospermic cellular phone users. A total number of ninety idiopathic infertile males referred from the Department of Dermatology and Andrology, were enrolled in this study. NAD + -IDH activity was measured in human seminal plasma by spectrophotometer. Computer-aided sperm analysis (CASA) following WHO criteria has been used for semen analyses. The results showed that IDH activity was increased in patients with prolonged cell phone daily use ≥4 h/day. Its level, correlated negatively with either the motility ratio percentages (r = -0.46, p  < 0.001) or the progressive motility percentages (r = -0.50, p  < 0.001) in the study groups. The current study suggests that NAD + -IDH in human seminal plasma could be one of seminal plasma biomarkers reflecting the mitochondrial function of spermatozoa. Alteration of its level could reflect the defective motility of sperms among some cases of cellular phone users.

HES6 enhances the motility of alveolar rhabdomyosarcoma cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wickramasinghe, Caroline M; MRC Laboratory of Molecular Biology, Addenbrooke's Hospital Cambridge, CB2 0QH; Domaschenz, Renae

Absract: HES6, a member of the hairy-enhancer-of-split family of transcription factors, plays multiple roles in myogenesis. It is a direct target of the myogenic transcription factor MyoD and has been shown to regulate the formation of the myotome in development, myoblast cell cycle exit and the organization of the actin cytoskeleton during terminal differentiation. Here we investigate the expression and function of HES6 in rhabdomyosarcoma, a soft tissue tumor which expresses myogenic genes but fails to differentiate into muscle. We show that HES6 is expressed at high levels in the subset of alveolar rhabdomyosarcomas expressing PAX/FOXO1 fusion genes (ARMSp). Knockdownmore » of HES6 mRNA in the ARMSp cell line RH30 reduces proliferation and cell motility. This phenotype is rescued by expression of mouse Hes6 which is insensitive to HES6 siRNA. Furthermore, expression microarray analysis indicates that the HES6 knockdown is associated with a decrease in the levels of Transgelin, (TAGLN), a regulator of the actin cytoskeleton. Knockdown of TAGLN decreases cell motility, whilst TAGLN overexpression rescues the motility defect resulting from HES6 knockdown. These findings indicate HES6 contributes to the pathogenesis of ARMSp by enhancing both proliferation and cell motility.« less

Step-wise loss of bacterial flagellar torsion confers progressive phagocytic evasion.

PubMed

Lovewell, Rustin R; Collins, Ryan M; Acker, Julie L; O'Toole, George A; Wargo, Matthew J; Berwin, Brent

2011-09-01

Phagocytosis of bacteria by innate immune cells is a primary method of bacterial clearance during infection. However, the mechanisms by which the host cell recognizes bacteria and consequentially initiates phagocytosis are largely unclear. Previous studies of the bacterium Pseudomonas aeruginosa have indicated that bacterial flagella and flagellar motility play an important role in colonization of the host and, importantly, that loss of flagellar motility enables phagocytic evasion. Here we use molecular, cellular, and genetic methods to provide the first formal evidence that phagocytic cells recognize bacterial motility rather than flagella and initiate phagocytosis in response to this motility. We demonstrate that deletion of genes coding for the flagellar stator complex, which results in non-swimming bacteria that retain an initial flagellar structure, confers resistance to phagocytic binding and ingestion in several species of the gamma proteobacterial group of Gram-negative bacteria, indicative of a shared strategy for phagocytic evasion. Furthermore, we show for the first time that susceptibility to phagocytosis in swimming bacteria is proportional to mot gene function and, consequently, flagellar rotation since complementary genetically- and biochemically-modulated incremental decreases in flagellar motility result in corresponding and proportional phagocytic evasion. These findings identify that phagocytic cells respond to flagellar movement, which represents a novel mechanism for non-opsonized phagocytic recognition of pathogenic bacteria.

Step-Wise Loss of Bacterial Flagellar Torsion Confers Progressive Phagocytic Evasion

PubMed Central

Lovewell, Rustin R.; Collins, Ryan M.; Acker, Julie L.; O'Toole, George A.; Wargo, Matthew J.; Berwin, Brent

2011-01-01

Phagocytosis of bacteria by innate immune cells is a primary method of bacterial clearance during infection. However, the mechanisms by which the host cell recognizes bacteria and consequentially initiates phagocytosis are largely unclear. Previous studies of the bacterium Pseudomonas aeruginosa have indicated that bacterial flagella and flagellar motility play an important role in colonization of the host and, importantly, that loss of flagellar motility enables phagocytic evasion. Here we use molecular, cellular, and genetic methods to provide the first formal evidence that phagocytic cells recognize bacterial motility rather than flagella and initiate phagocytosis in response to this motility. We demonstrate that deletion of genes coding for the flagellar stator complex, which results in non-swimming bacteria that retain an initial flagellar structure, confers resistance to phagocytic binding and ingestion in several species of the gamma proteobacterial group of Gram-negative bacteria, indicative of a shared strategy for phagocytic evasion. Furthermore, we show for the first time that susceptibility to phagocytosis in swimming bacteria is proportional to mot gene function and, consequently, flagellar rotation since complementary genetically- and biochemically-modulated incremental decreases in flagellar motility result in corresponding and proportional phagocytic evasion. These findings identify that phagocytic cells respond to flagellar movement, which represents a novel mechanism for non-opsonized phagocytic recognition of pathogenic bacteria. PMID:21949654

Passive exercise of the lower limbs and trunk alleviates decreased intestinal motility in patients in the intensive care unit after cardiovascular surgery.

PubMed

Morisawa, Tomoyuki; Takahashi, Tetsuya; Sasanuma, Naoki; Mabuchi, Satoshi; Takeda, Kenta; Hori, Naoto; Ohashi, Naotsugu; Ide, Takeshi; Domen, Kazuhisa; Nishi, Shinichi

2017-02-01

[Purpose] The purpose of this study was to clarify the effects of passive exercise of the lower limbs and trunk (PELT) in ICU patients after cardiovascular surgery with decreased bowel motility. [Subjects and Methods] Ten ICU patients with clinically-apparent decreased bowel motility during the period of April to July 2016 were enrolled this study. Bowel sounds (BS) for 5 minutes at rest and 5 minutes after PELT were recorded through an electronic stethoscope. A frequency analysis was performed and the BS before and after PELT were compared. In addition, the percent change in BS before and after PELT was determined, and the relationship between the percent change in BS and individual parameters (invasiveness of surgery, inflammation, nutrition, renal function) was examined. [Results] Average BS (integral value) for 5 minutes before and after PELT were 63.1 ± 41.3 mVsec and 115.0 ± 57.8 mVsec, respectively; therefore, BS was significantly increased by PELT. When compared to patients at rest, a significant increase was found 0-4 minutes after PELT. None of the individual parameters was significantly correlated with the percent change. [Conclusion] PELT can increase the bowel motility of ICU patients with decreased bowel motility.

Computerized in vitro test for chemical toxicity based on tetrahymena swimming patterns

NASA Technical Reports Server (NTRS)

Noever, David A.; Matsos, Helen C.; Cronise, Raymond J.; Looger, Loren L.; Relwani, Rachna A.; Johnson, Jacqueline U.

1994-01-01

An apparatus and method for rapidly determining chemical toxicity was evaluated. The toxicity monitor includes an automated scoring of how motile biological cells (Tetrahymena pyriformis) slow down or otherwise change their swimming patterns in a hostile chemical environment. The device, called the Motility Assay Apparatus (MAA) is tested for 30 second determination of chemical toxicity in 20 aqueous samples containing trace organics and salts. With equal or better detection limits, results compare favorably to in vivo animal tests of eye irritancy, in addition to agreeing for all chemicals with previous manual evaluations of single cell motility.

The physics of the unconventional motility strategy of euglenids

NASA Astrophysics Data System (ADS)

Arroyo, Marino; Noselli, Giovanni; Desimone, Antonio

Euglenids are a family of unicellular protists, which use flagella to move in a fluid. However, they are also capable of performing elegantly concerted large amplitude deformations of the cell shape, in what is known as metaboly. To perform metaboly, euglenids use an elaborate cortical complex capable of actively imposing spatially modulated shear deformations on the cell surface. This mode of cell deformation has been linked to motility, but biophysical studies have demonstrated that it leads to very small swimming velocities as compared to flagellar locomotion. Furthermore, why would these cells possess two elaborate apparatus for the same function remains unclear. In this work, we combine experimental observations of euglena gracilis cells with theoretical models to shed light into the function of metaboly. The theoretical models account for the force generation and shape evolution at the cell envelop, together with the mechanical interaction of the cell with its environment. We characterize the efficiency of the two modes of locomotion of this cells in terms of the physical nature of their environment. ERC AdG 340685 MicroMotility.

Loss of Actin-Based Motility Impairs Ectromelia Virus Release In Vitro but Is Not Critical to Spread In Vivo.

PubMed

Duncan, Melanie Laura; Horsington, Jacquelyn; Eldi, Preethi; Al Rumaih, Zahrah; Karupiah, Gunasegaran; Newsome, Timothy P

2018-03-05

Ectromelia virus (ECTV) is an orthopoxvirus and the causative agent of mousepox. Like other poxviruses such as variola virus (agent of smallpox), monkeypox virus and vaccinia virus (the live vaccine for smallpox), ECTV promotes actin-nucleation at the surface of infected cells during virus release. Homologs of the viral protein A36 mediate this function through phosphorylation of one or two tyrosine residues that ultimately recruit the cellular Arp2/3 actin-nucleating complex. A36 also functions in the intracellular trafficking of virus mediated by kinesin-1. Here, we describe the generation of a recombinant ECTV that is specifically disrupted in actin-based motility allowing us to examine the role of this transport step in vivo for the first time. We show that actin-based motility has a critical role in promoting the release of virus from infected cells in vitro but plays a minor role in virus spread in vivo. It is likely that loss of microtubule-dependent transport is a major factor for the attenuation observed when A36R is deleted.

Stimulatory action of itopride hydrochloride on colonic motor activity in vitro and in vivo.

PubMed

Tsubouchi, Tadashi; Saito, Takaharu; Mizutani, Fujie; Yamauchi, Toshie; Iwanaga, Yuji

2003-08-01

We investigated the effects of itopride hydrochloride (itopride, N-[4-[2-(dimethylamino)ethoxy]benzyl]-3,4-dimethoxybenzamide hydrochloride), a gastroprokinetic agent, on the colonic motor activity in vitro and in vivo, in comparison with benzamides, cisapride hydrate (cisapride), and mosapride citrate (mosapride). Itopride stimulated both peristaltic and segmental motility induced by applying intraluminal pressure to the isolated guinea pig colon. Although cisapride and mosapride enhanced the segmental motility, they markedly reduced the peristaltic motility. In conscious dogs with implanted strain gauge force transducers, itopride stimulated contractile activity in the gastrointestinal tract from the stomach to the colon. Cisapride stimulated contractile activity in the gastric antrum, ileum, and ascending colon. Mosapride stimulated contractile activity only in the gastric antrum and ileum. In guinea pigs and rats, itopride accelerated colonic luminal transit. On the other hand, cisapride and mosapride failed to enhance colonic transit. These results demonstrate that itopride has a stimulatory action on colonic peristalsis, propelling colonic luminal contents, different from that of cisapride and mosapride. Therefore, itopride may be a useful drug for the treatment of functional bowel disorders such as functional constipation.

Forkhead Transcription Factor Fd3F Cooperates with Rfx to Regulate a Gene Expression Program for Mechanosensory Cilia Specialization

PubMed Central

Newton, Fay G.; zur Lage, Petra I.; Karak, Somdatta; Moore, Daniel J.; Göpfert, Martin C.; Jarman, Andrew P.

2012-01-01

Summary Cilia have evolved hugely diverse structures and functions to participate in a wide variety of developmental and physiological processes. Ciliary specialization requires differences in gene expression, but few transcription factors are known to regulate this, and their molecular function is unclear. Here, we show that the Drosophila Forkhead box (Fox) gene, fd3F, is required for specialization of the mechanosensory cilium of chordotonal (Ch) neurons. fd3F regulates genes for Ch-specific axonemal dyneins and TRPV ion channels, which are required for sensory transduction, and retrograde transport genes, which are required to differentiate their distinct motile and sensory ciliary zones. fd3F is reminiscent of vertebrate Foxj1, a motile cilia regulator, but fd3F regulates motility genes as part of a broader sensory regulation program. Fd3F cooperates with the pan-ciliary transcription factor, Rfx, to regulate its targets directly. This illuminates pathways involved in ciliary specialization and the molecular mechanism of transcription factors that regulate them. PMID:22698283

Loss of Actin-Based Motility Impairs Ectromelia Virus Release In Vitro but Is Not Critical to Spread In Vivo

PubMed Central

Duncan, Melanie Laura; Horsington, Jacquelyn; Eldi, Preethi; Al Rumaih, Zahrah; Karupiah, Gunasegaran

2018-01-01

Ectromelia virus (ECTV) is an orthopoxvirus and the causative agent of mousepox. Like other poxviruses such as variola virus (agent of smallpox), monkeypox virus and vaccinia virus (the live vaccine for smallpox), ECTV promotes actin-nucleation at the surface of infected cells during virus release. Homologs of the viral protein A36 mediate this function through phosphorylation of one or two tyrosine residues that ultimately recruit the cellular Arp2/3 actin-nucleating complex. A36 also functions in the intracellular trafficking of virus mediated by kinesin-1. Here, we describe the generation of a recombinant ECTV that is specifically disrupted in actin-based motility allowing us to examine the role of this transport step in vivo for the first time. We show that actin-based motility has a critical role in promoting the release of virus from infected cells in vitro but plays a minor role in virus spread in vivo. It is likely that loss of microtubule-dependent transport is a major factor for the attenuation observed when A36R is deleted. PMID:29510577

[Physiotherapy for juvenile idiopathic arthritis].

PubMed

Spamer, M; Georgi, M; Häfner, R; Händel, H; König, M; Haas, J-P

2012-07-01

Control of disease activity and recovery of function are major issues in the treatment of children and adolescents suffering from juvenile idiopathic arthritis (JIA). Functional therapies including physiotherapy are important components in the multidisciplinary teamwork and each phase of the disease requires different strategies. While in the active phase of the disease pain alleviation is the main focus, the inactive phase requires strategies for improving motility and function. During remission the aim is to regain general fitness by sports activities. These phase adapted strategies must be individually designed and usually require a combination of different measures including physiotherapy, occupational therapy, massage as well as other physical procedures and sport therapy. There are only few controlled studies investigating the effectiveness of physical therapies in JIA and many strategies are derived from long-standing experience. New results from physiology and sport sciences have contributed to the development in recent years. This report summarizes the basics and main strategies of physical therapy in JIA.

Spontaneous Division and Motility in Active Nematic Droplets

NASA Astrophysics Data System (ADS)

Giomi, Luca; DeSimone, Antonio

2014-04-01

We investigate the mechanics of an active droplet endowed with internal nematic order and surrounded by an isotropic Newtonian fluid. Using numerical simulations we demonstrate that, due to the interplay between the active stresses and the defective geometry of the nematic director, this system exhibits two of the fundamental functions of living cells: spontaneous division and motility, by means of self-generated hydrodynamic flows. These behaviors can be selectively activated by controlling a single physical parameter, namely, an active variant of the capillary number.

Ccdc11 is a novel centriolar satellite protein essential for ciliogenesis and establishment of left-right asymmetry.

PubMed

Silva, Erica; Betleja, Ewelina; John, Emily; Spear, Philip; Moresco, James J; Zhang, Siwei; Yates, John R; Mitchell, Brian J; Mahjoub, Moe R

2016-01-01

The establishment of left-right (L-R) asymmetry in vertebrates is dependent on the sensory and motile functions of cilia during embryogenesis. Mutations in CCDC11 disrupt L-R asymmetry and cause congenital heart disease in humans, yet the molecular and cellular functions of the protein remain unknown. Here we demonstrate that Ccdc11 is a novel component of centriolar satellites-cytoplasmic granules that serve as recruitment sites for proteins destined for the centrosome and cilium. Ccdc11 interacts with core components of satellites, and its loss disrupts the subcellular organization of satellite proteins and perturbs primary cilium assembly. Ccdc11 colocalizes with satellite proteins in human multiciliated tracheal epithelia, and its loss inhibits motile ciliogenesis. Similarly, depletion of CCDC11 in Xenopus embryos causes defective assembly and motility of cilia in multiciliated epidermal cells. To determine the role of CCDC11 during vertebrate development, we generated mutant alleles in zebrafish. Loss of CCDC11 leads to defective ciliogenesis in the pronephros and within the Kupffer's vesicle and results in aberrant L-R axis determination. Our results highlight a critical role for Ccdc11 in the assembly and function of motile cilia and implicate centriolar satellite-associated proteins as a new class of proteins in the pathology of L-R patterning and congenital heart disease. © 2016 Silva, Betleja, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Involvement of FFA1 and FFA4 in the regulation of cellular functions during tumor progression in colon cancer cells.

PubMed

Takahashi, Kaede; Fukushima, Kaori; Onishi, Yuka; Minami, Kanako; Otagaki, Shiho; Ishimoto, Kaichi; Fukushima, Nobuyuki; Honoki, Kanya; Tsujiuchi, Toshifumi

2018-08-01

Free fatty acid receptor 1 (FFA1) and FFA4 mediate a variety of biological responses through binding of medium- and long-chain free fatty acids. The aim of this study was to investigate an involvement of FFA1 and FFA4 in the regulation of cellular functions during tumor progression in colon cancer cells. The long-term fluorouracil (5-FU) and cisplatin (CDDP) treated cells were generated from DLD1 cells (DLD-5FU and DLD-CDDP cells, respectively). FFAR1 expressions were lower in DLD-5FU and DLD-CDDP cells than in DLD1 cells. In contrast, DLD-5FU and DLD-CDDP cells showed the high FFAR4 expressions, compared with DLD1 cells. The cell motile activities of DLD-5FU and DLD-CDDP cells were reduced by GW9508 which is an agonist of FFA1 and FFA4. Moreover, GW1100, an antagonist of FFA1, inhibited the cell motile activities of DLD-5FU and DLD-CDDP cells. To evaluate whether FFA1 and FFA4 regulate the enhancement of cell motility, invasion and colony formation, highly migratory (hmDLD1) cells were established from DLD1 cells. FFAR1 expression was significantly higher in hmDLD1 cells than in DLD1 cells, but no change of FFAR4 expression was observed. The elevated cell motile and invasive activities and colony formation of hmDLD1 cells were suppressed by FFA1 inhibition. These results suggest that FFA1 and FFA4 are involved in the regulation of cellular functions during tumor progression in colon cancer DLD1 cells. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of tongue force training on bulbar motor function in the female SOD1-G93A rat model of Amyotrophic Lateral Sclerosis

PubMed Central

Ma, Delin; Shuler, Jeffrey M.; Kumar, Aishwarya; Stanford, Quincy R.; Tungtur, Sudheer; Nishimune, Hiroshi; Stanford, John A.

2016-01-01

Background The use of exercise in Amyotrophic Lateral Sclerosis (ALS) is controversial. Although moderate exercise appears to be beneficial for limb muscles in ALS, the effects of exercise on bulbar muscles such as the tongue have not been studied. Objective The aim of this study was to determine the effects of tongue force training on bulbar motor function in the SOD1-G93A rat model of ALS. Methods We compared the effects of tongue force training on bulbar motor function and neuromuscular junction (NMJ) innervation in female SOD1-G93A rats and age-matched female wild-type controls. Half of each group underwent afternoon tongue force training sessions, while all rats were tested under minimal force conditions in the mornings. Results Tongue force did not differ between the SOD1-G93A rats and healthy controls during the morning testing sessions, nor was it affected by training. Surprisingly, decreases in tongue motility, the number of licks per session, and body weight were greater in the tongue force-trained SOD1-G93A rats. Forelimb grip force, survival, and denervation of the genioglossus muscle did not differ between the trained and untrained SOD1-G93A rats. Genioglossus innervation was correlated with changes in tongue force but not tongue motility in SOD1-G93A rats at end stage. Conclusions The results indicate a potential deleterious effect of tongue force training on tongue motility in female SOD1-G93A rats. The lack of relationship between genioglossus innervation and tongue motility suggest that factors other than lower motor neuron integrity likely accounted for this effect. PMID:27573800

Cell Surface Mechanochemistry and the Determinants of Bleb Formation, Healing, and Travel Velocity

PubMed Central

Manakova, Kathryn; Yan, Huaming; Lowengrub, John; Allard, Jun

2016-01-01

Blebs are pressure-driven cell protrusions implicated in cellular functions such as cell division, apoptosis, and cell motility, including motility of protease-inhibited cancer cells. Because of their mechanical nature, blebs inform us about general cell-surface mechanics, including membrane dynamics, pressure propagation throughout the cytoplasm, and the architecture and dynamics of the actin cortex. Mathematical models including detailed fluid dynamics have previously been used to understand bleb expansion. Here, we develop mathematical models in two and three dimensions on longer timescales that recapitulate the full bleb life cycle, including both expansion and healing by cortex reformation, in terms of experimentally accessible biophysical parameters such as myosin contractility, osmotic pressure, and turnover of actin and ezrin. The model provides conditions under which blebbing occurs, and naturally gives rise to traveling blebs. The model predicts conditions under which blebs travel or remain stationary, as well as the bleb traveling velocity, a quantity that has remained elusive in previous models. As previous studies have used blebs as reporters of membrane tension and pressure dynamics within the cell, we have used our system to investigate various pressure equilibration models and dynamic, nonuniform membrane tension to account for the shape of a traveling bleb. We also find that traveling blebs tend to expand in all directions unless otherwise constrained. One possible constraint could be provided by spatial heterogeneity in, for example, adhesion density. PMID:27074688

Novel interactions between erythroblast macrophage protein and cell migration.

PubMed

Javan, Gulnaz T; Can, Ismail; Yeboah, Fred; Lee, Youngil; Soni, Shivani

2016-09-01

Erythroblast macrophage protein is a novel protein known to mediate attachment of erythroid cells to macrophages to form erythroblastic islands in bone marrow during erythropoiesis. Emp-null macrophages are small with round morphologies, and lack cytoplasmic projections which imply immature structure. The role of Emp in macrophage development and function is not fully elucidated. Macrophages perform varied functions (e.g. homeostasis, erythropoiesis), and are implicated in numerous pathophysiological conditions such as cellular malignancy. The objective of the current study is to investigate the interaction of Emp with cytoskeletal- and cell migration-associated proteins involved in macrophage functions. A short hairpin RNA lentiviral system was use to down-regulate the expression of Emp in macrophage cells. A cell migration assay revealed that the relocation of macrophages was significantly inhibited when Emp expression was decreased. To further analyze changes in gene expression related to cell motility, PCR array was performed by down-regulating Emp expression. The results indicated that expression of mitogen-activated protein kinase 1 and thymoma viral proto-oncogene 1 were significantly higher when Emp was down-regulated. The results implicate Emp in abnormal cell motility, thus, warrants to assess its role in cancer where tumor cell motility is required for invasion and metastasis. Copyright © 2016 Elsevier Inc. All rights reserved.

Nuclear Scintigraphy in Practice: Gastrointestinal Motility.

PubMed

Solnes, Lilja B; Sheikhbahaei, Sara; Ziessman, Harvey A

2018-05-29

The purpose of this article is to describe the clinical utility of state-of-theart gastrointestinal transit scintigraphy, including the standardized esophageal transit, solid and liquid gastric emptying, small-bowel transit, colon transit, and whole-gut transit scintigraphy, with an emphasis on procedure performance. Radionuclide gastrointestinal motility studies are noninvasive, quantitative, and physiologic diagnostic tools for evaluating patients with gastrointestinal complaints.

The GIT–PIX complexes regulate the chemotactic response of rat basophilic leukaemia cells

PubMed Central

Gavina, Manuela; Za, Lorena; Molteni, Raffaella; Pardi, Ruggero; Curtis, Ivan de

2009-01-01

Background information. Cell motility entails the reorganization of the cytoskeleton and membrane trafficking for effective protrusion. The GIT–PIX protein complexes are involved in the regulation of cell motility and adhesion and in the endocytic traffic of members of the family of G-protein-coupled receptors. We have investigated the function of the endogenous GIT complexes in the regulation of cell motility stimulated by fMLP (formyl-Met-Leu-Phe) peptide, in a rat basophilic leukaemia RBL-2H3 cell line stably expressing an HA (haemagglutinin)-tagged receptor for the fMLP peptide. Results. Our analysis shows that RBL cells stably transfected with the chemoattractant receptor expressed both GIT1–PIX and GIT2–PIX endogenous complexes. We have used silencing of the different members of the complex by small interfering RNAs to study the effects on a number of events linked to agonist-induced cell migration. We found that cell adhesion was not affected by depletion of any of the proteins of the GIT complex, whereas agonist-enhanced cell spreading was inhibited. Analysis of agonist-stimulated haptotactic cell migration indicated a specific positive effect of GIT1 depletion on trans-well migration. The internalization of the formyl-peptide receptor was also inhibited by depletion of GIT1 and GIT2. The effects of the GIT complexes on trafficking of the receptors was confirmed by an antibody-enhanced agonist-induced internalization assay, showing that depletion of PIX, GIT1 or GIT2 protein caused decreased perinuclear accumulation of internalized receptors. Conclusions. Our results show that endogenous GIT complexes are involved in the regulation of chemoattractant-induced cell motility and receptor trafficking, and support previous findings indicating an important function of the GIT complexes in the regulation of different G-protein-coupled receptors. Our results also indicate that endogenous GIT1 and GIT2 regulate distinct subsets of agonist-induced responses and suggest a possible functional link between the control of receptor trafficking and the regulation of cell motility by GIT proteins. PMID:19912111

In Helicobacter pylori auto-inducer-2, but not LuxS/MccAB catalysed reverse transsulphuration, regulates motility through modulation of flagellar gene transcription

PubMed Central

2010-01-01

Background LuxS may function as a metabolic enzyme or as the synthase of a quorum sensing signalling molecule, auto-inducer-2 (AI-2); hence, the mechanism underlying phenotypic changes upon luxS inactivation is not always clear. In Helicobacter pylori, we have recently shown that, rather than functioning in recycling methionine as in most bacteria, LuxS (along with newly-characterised MccA and MccB), synthesises cysteine via reverse transsulphuration. In this study, we investigated whether and how LuxS controls motility of H. pylori, specifically if it has its effects via luxS-required cysteine metabolism or via AI-2 synthesis only. Results We report that disruption of luxS renders H. pylori non-motile in soft agar and by microscopy, whereas disruption of mccAHp or mccBHp (other genes in the cysteine provision pathway) does not, implying that the lost phenotype is not due to disrupted cysteine provision. The motility defect of the ΔluxSHp mutant was complemented genetically by luxSHp and also by addition of in vitro synthesised AI-2 or 4, 5-dihydroxy-2, 3-pentanedione (DPD, the precursor of AI-2). In contrast, exogenously added cysteine could not restore motility to the ΔluxSHp mutant, confirming that AI-2 synthesis, but not the metabolic effect of LuxS was important. Microscopy showed reduced number and length of flagella in the ΔluxSHp mutant. Immunoblotting identified decreased levels of FlaA and FlgE but not FlaB in the ΔluxSHp mutant, and RT-PCR showed that the expression of flaA, flgE, motA, motB, flhA and fliI but not flaB was reduced. Addition of DPD but not cysteine to the ΔluxSHp mutant restored flagellar gene transcription, and the number and length of flagella. Conclusions Our data show that as well as being a metabolic enzyme, H. pylori LuxS has an alternative role in regulation of motility by modulating flagellar transcripts and flagellar biosynthesis through production of the signalling molecule AI-2. PMID:20691071

Long-term preservation of chilled canine semen: effect of commercial and laboratory prepared extenders.

PubMed

Iguer-ouada, M; Verstegen, J P

2001-01-15

The present study was conducted to evaluate chilled semen conservation over time in 3 commercial and 4 laboratory prepared extenders, including a new Tris-glucose extender. The beneficial effect of adding egg yolk to these media was also analyzed. The effects of these extenders on motility and acrosome reaction were characterized objectively using a computer-aided semen analyzer and the chlortetracycline staining, respectively. No significant differences were observed when comparing the different commercial extenders without egg yolk, but addition of egg yolk improved all motility parameters significantly (preservation of 50% of motility was observed at 3.2+/-1, 2.9+/-0.5, 2.3+/-0.5, 8.5+/-0.2, 5.4+/-1.1, 5.2+/-0.4 d, for Biladyl, green extender and fresh-phos extenders without and with egg yolk, respectively). Motility parameters were best preserved in egg yolk supplemented Biladyl extender with a mean percentage of 86.3+/-10.5 motile spermatozoa after 7 d at 4 degrees C. Efficacy of egg yolk-supplemented commercial extenders on sperm motility at 4 degrees C was (in decreasing order) as follows: Biladyl > green extender > fresh-phos. However, high quality motility and the percentage of motile spermatozoa were highest with some of the laboratory prepared extenders: a 50% conservation rate of motile spermatozoa was observed following the use of supplemented egg yolk extenders. These are classified in decreasing order as follows: Tris-glucose (13+/-1 d) > Tris-fructose (9.7+/-0.6) > EDTA (4.+/-0.6 d) > Tris-bes (3.6+/-1.1 d). A low concentration of motile spermatozoa was still observed in the Tris-glucose egg yolk extender 16 d after collection, clearly demonstrating the importance of the medium and the beneficial effect of egg yolk on sperm motility of 4 degrees C chilled semen. Similar effects of extender were observed for acrosome reactions. Egg yolk clearly had a protective effect reducing acrosome reactions significantly in all media tested as follows: the highest acrosome losses were observed in the fresh-phos and EDTA extenders without egg yolk; the lowest rate was observed with Tris-glucose supplemented egg yolk extender. In conclusion, at 4 degrees C, egg yolk extender best-protected sperm motility parameters. Differences in osmolarity between the extenders in terms of substrate related to sperm metabolic activity may explain the optimal results obtained using egg yolk-supplemented Tris-glucose extender, which preserved motility and acrosome integrity in chilled dog semen. These results indicated that good quality dog spermatozoa could be preserved for up to 10 d.

A Versatile Class of Cell Surface Directional Motors Gives Rise to Gliding Motility and Sporulation in Myxococcus xanthus

PubMed Central

Wartel, Morgane; Czerwinski, Fabian; Le Gall, Anne-Valérie; Mauriello, Emilia M. F.; Bergam, Ptissam; Brun, Yves V.; Shaevitz, Joshua; Mignot, Tâm

2013-01-01

Eukaryotic cells utilize an arsenal of processive transport systems to deliver macromolecules to specific subcellular sites. In prokaryotes, such transport mechanisms have only been shown to mediate gliding motility, a form of microbial surface translocation. Here, we show that the motility function of the Myxococcus xanthus Agl-Glt machinery results from the recent specialization of a versatile class of bacterial transporters. Specifically, we demonstrate that the Agl motility motor is modular and dissociates from the rest of the gliding machinery (the Glt complex) to bind the newly expressed Nfs complex, a close Glt paralogue, during sporulation. Following this association, the Agl system transports Nfs proteins directionally around the spore surface. Since the main spore coat polymer is secreted at discrete sites around the spore surface, its transport by Agl-Nfs ensures its distribution around the spore. Thus, the Agl-Glt/Nfs machineries may constitute a novel class of directional bacterial surface transporters that can be diversified to specific tasks depending on the cognate cargo and machinery-specific accessories. PMID:24339744

Diadenosine tetraphosphate (Ap4A) and triphosphate (Ap3A) signaling of human sperm motility.

PubMed

Chan, P J; Su, B C; Tredway, D R

1991-01-01

The ubiquitous dinucleotide polyphosphate, diadenosine tetraphosphate (Ap4A), has been shown to be a signal molecule for DNA replication in mammalian cells. In this study, Ap4A and a related compound, diadenosine triphosphate (Ap3A), were tested for possible signaling functions in human spermatozoa. A computerized automated semen analyzer was used to detect changes in spermatozoa motility parameters. Cryopreserved-thawed donor spermatozoa were washed and incubated in 0.1 mM Ap4A, 0.1 mM Ap3A, or control medium. The data indicated that both Ap4A and Ap3A decreased the percentage of motile spermatozoa after 4 or more hours of incubation in vitro. The two dinucleotide polyphosphates caused an increase in the amplitude of lateral spermatozoa head displacement parameter only at the start of incubation. The other spermatozoa kinematic parameters were unaffected. No opposing ying-yang dual actions of Ap4A to Ap3A were seen. From the results, Ap4A and Ap3A were observed to be potential inhibitory signals of spermatozoa motility after prolonged exposure.

Rab coupling protein mediated endosomal recycling of N-cadherin influences cell motility.

PubMed

Lindsay, Andrew J; McCaffrey, Mary W

2017-12-01

Rab coupling protein (RCP) is a Rab GTPase effector that functions in endosomal recycling. The RCP gene is frequently amplified in breast cancer, leading to increased cancer aggressiveness. Furthermore, RCP enhances the motility of ovarian cancer cells by coordinating the recycling of α5β1 integrin and EGF receptor to the leading edge of migrating cells. Here we report that RCP also influences the motility of lung adenocarcinoma cells. Knockdown of RCP inhibits the motility of A549 cells in 2D and 3D migration assays, while its overexpression enhances migration in these assays. Depletion of RCP leads to a reduction in N-cadherin protein levels, which could be restored with lysosomal inhibitors. Trafficking assays revealed that RCP knockdown inhibits the return of endocytosed N-cadherin to the cell surface. We propose that RCP regulates the endosomal recycling of N-cadherin, and in its absence N-cadherin is diverted to the degradative pathway. The increased aggressiveness of tumour cells that overexpress RCP may be due to biased recycling of N-cadherin in metastatic cancer cells.

Motility, morphology and phylogeny of the plasmodial worm, Ceratomyxa vermiformis n. sp. (Cnidaria: Myxozoa: Myxosporea).

PubMed

Adriano, E A; Okamura, B

2017-02-01

The Myxozoa demonstrate extensive morphological simplification and miniaturization relative to their free-living cnidarian ancestors. This is particularly pronounced in the highly derived myxosporeans, which develop as plasmodia and pseudoplasmodia. To date, motility in these stages has been linked with membrane deformation (e.g. as pseudopodia and mobile folds). Here we illustrate a motile, elongate plasmodium that undergoes coordinated undulatory locomotion, revealing remarkable convergence to a functional worm at the cellular level. Ultrastructural and confocal analyses of these plasmodia identify a highly differentiated external layer containing an actin-rich network, long tubular mitochondria, abundant microtubules, a secreted glycocalyx layer, and an internal region where sporogony occurs and which contains homogeneously distributed granular/fibrillar material. We consider how some of these features may support motility. We also describe the species based on spore morphology and SSU rDNA sequence data, undertake molecular phylogenetic analysis to place it within an early-diverging clade of the ceratomyxids, and evaluate the resultant implications for classification (validity of the genus Meglitschia) and for inferring early host environments (freshwater) of ceratomyxids.

Unique among ciliopathies: primary ciliary dyskinesia, a motile cilia disorder.

PubMed

Praveen, Kavita; Davis, Erica E; Katsanis, Nicholas

2015-01-01

Primary ciliary dyskinesia (PCD) is a ciliopathy, but represents the sole entity from this class of disorders that results from the dysfunction of motile cilia. Characterized by respiratory problems appearing in childhood, infertility, and situs defects in ~50% of individuals, PCD has an estimated prevalence of approximately 1 in 10,000 live births. The diagnosis of PCD can be prolonged due to a lack of disease awareness, coupled with the fact that symptoms can be confused with other more common genetic disorders, such as cystic fibrosis, or environmental insults that result in frequent respiratory infections. A primarily autosomal recessive disorder, PCD is genetically heterogeneous with >30 causal genes identified, posing significant challenges to genetic diagnosis. Here, we provide an overview of PCD as a disorder underscored by impaired ciliary motility; we discuss the recent advances towards uncovering the genetic basis of PCD; we discuss the molecular knowledge gained from PCD gene discovery, which has improved our understanding of motile ciliary assembly; and we speculate on how accelerated diagnosis, together with detailed phenotypic data, will shape the genetic and functional architecture of this disorder.

In vitro motility evaluation of aggregated cancer cells by means of automatic image processing.

PubMed

De Hauwer, C; Darro, F; Camby, I; Kiss, R; Van Ham, P; Decaesteker, C

1999-05-01

Set up of an automatic image processing based method that enables the motility of in vitro aggregated cells to be evaluated for a number of hours. Our biological model included the PC-3 human prostate cancer cell line growing as a monolayer on the bottom of Falcon plastic dishes containing conventional culture media. Our equipment consisted of an incubator, an inverted phase contrast microscope, a Charge Coupled Device (CCD) video camera, and a computer equipped with an image processing software developed in our laboratory. This computer-assisted microscope analysis of aggregated cells enables global cluster motility to be evaluated. This analysis also enables the trajectory of each cell to be isolated and parametrized within a given cluster or, indeed, the trajectories of individual cells outside a cluster. The results show that motility inside a PC-3 cluster is not restricted to slight motion due to cluster expansion, but rather consists of a marked cell movement within the cluster. The proposed equipment enables in vitro aggregated cell motility to be studied. This method can, therefore, be used in pharmacological studies in order to select anti-motility related compounds. The compounds selected by the equipment described could then be tested in vivo as potential anti-metastatic.

New insights into epididymal biology and function.

PubMed

Cornwall, Gail A

2009-01-01

The epididymis performs an important role in the maturation of spermatozoa including their acquisition of progressive motility and fertilizing ability. However, the molecular mechanisms that govern these maturational events are still poorly defined. This review focuses on recent progress in our understanding of epididymal function including its development, role of the luminal microenvironment in sperm maturation, regulation and novel mechanisms the epididymis utilizes to carry out some of its functions. A systematic search of Pubmed was carried out using the search term 'epididymis'. Articles that were published in the English language until the end of August 2008 and that focused on the specific topics described above were included. Additional papers cited in the primary reference were also included. While the majority of these findings were the result of studies in animal models, recent studies in the human epididymis are also presented including gene profiling studies to examine regionalized expression in normal epididymides as well as in those from vasectomized patients. Significant progress has been made in our understanding of epididymal function providing new insights that ultimately could improve human health. The data also indicate that the human epididymis plays an important role in sperm maturation but has unique properties compared with animal models.

The effect of loss of O-antigen ligase on phagocytic susceptibility of motile and non-motile Pseudomonas aeruginosa.

PubMed

Demirdjian, Sally; Schutz, Kristin; Wargo, Matthew J; Lam, Joseph S; Berwin, Brent

2017-12-01

The bacterial pathogen Pseudomonas aeruginosa undergoes adaptation and selection over the course of chronic respiratory tract infections which results in repeatedly-observed phenotypic changes that are proposed to enable its persistence. Two of the clinically significant P. aeruginosa phenotypic changes are loss of flagellar motility and modifications to LPS structure, including loss of O-antigen expression. The effect of loss of O-antigen, frequently described as conversion from smooth to rough LPS, and the combined effect of loss of motility and O-antigen on phagocytic susceptibility by immune cells remain unknown. To address this, we generated genetic deletion mutants of waaL, which encodes the O-antigen ligase responsible for linking O-antigen to lipid A-core oligosaccharide, in both motile and non-motile P. aeruginosa strains. With the use of these bacterial strains we provide the first demonstration that, despite a progressive selection for P. aeruginosa with rough LPS during chronic pulmonary infections, loss of the LPS O-antigen does not confer phagocytic resistance in vitro. However, use of the waaLmotABmotCD mutant revealed that loss of motility confers resistance to phagocytosis regardless of the smooth or rough LPS phenotype. These findings reveal how the O-antigen of P. aeruginosa can influence bacterial clearance during infection and expand our current knowledge about the impact of bacterial phenotypic changes during chronic infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Parallel evolution of auditory genes for echolocation in bats and toothed whales.

PubMed

Shen, Yong-Yi; Liang, Lu; Li, Gui-Sheng; Murphy, Robert W; Zhang, Ya-Ping

2012-06-01

The ability of bats and toothed whales to echolocate is a remarkable case of convergent evolution. Previous genetic studies have documented parallel evolution of nucleotide sequences in Prestin and KCNQ4, both of which are associated with voltage motility during the cochlear amplification of signals. Echolocation involves complex mechanisms. The most important factors include cochlear amplification, nerve transmission, and signal re-coding. Herein, we screen three genes that play different roles in this auditory system. Cadherin 23 (Cdh23) and its ligand, protocadherin 15 (Pcdh15), are essential for bundling motility in the sensory hair. Otoferlin (Otof) responds to nerve signal transmission in the auditory inner hair cell. Signals of parallel evolution occur in all three genes in the three groups of echolocators--two groups of bats (Yangochiroptera and Rhinolophoidea) plus the dolphin. Significant signals of positive selection also occur in Cdh23 in the Rhinolophoidea and dolphin, and Pcdh15 in Yangochiroptera. In addition, adult echolocating bats have higher levels of Otof expression in the auditory cortex than do their embryos and non-echolocation bats. Cdh23 and Pcdh15 encode the upper and lower parts of tip-links, and both genes show signals of convergent evolution and positive selection in echolocators, implying that they may co-evolve to optimize cochlear amplification. Convergent evolution and expression patterns of Otof suggest the potential role of nerve and brain in echolocation. Our synthesis of gene sequence and gene expression analyses reveals that positive selection, parallel evolution, and perhaps co-evolution and gene expression affect multiple hearing genes that play different roles in audition, including voltage and bundle motility in cochlear amplification, nerve transmission, and brain function.

Metformin blocks mitochondrial membrane potential and inhibits sperm motility in fresh and refrigerated boar spermatozoa.

PubMed

Hurtado de Llera, A; Martin-Hidalgo, D; Garcia-Marin, L J; Bragado, M J

2018-06-01

Metformin is clinically used to treat diabetes. Given its role-impacting metabolism, metformin has been also added to semen cryopreservation media showing specie-dependent effects. We aimed to investigate metformin effects in both fresh (38.5°C for 2, 24 hr) and refrigerated (17°C for 10 days) boar spermatozoa. Metformin (2 hr) does not affect fresh sperm viability, membrane lipid organization nor acrosome integrity. However, metformin (24 hr) blocks sperm ΔΨm and significantly reduces % motile spermatozoa (65%), % progressive spermatozoa (50%), % rapid (100%), velocities VCL (69%), VSL (86%), VAP (78%) and motility coefficients. Metformin-including extender does not modify sperm viability, membrane lipid organization or acrosome integrity. Furthermore, it significantly reduces high ΔΨ-population spermatozoa at refrigeration day 4. Metformin also significantly reduces sperm motility during refrigeration. Summarizing, metformin inhibits both boar sperm ΔΨ and motility in any sperm condition studied: fresh and refrigerated. These findings dissuade metformin as an additive to improve boar sperm quality. © 2018 Blackwell Verlag GmbH.

A protein secretion system linked to bacteroidete gliding motility and pathogenesis

PubMed Central

Sato, Keiko; Naito, Mariko; Yukitake, Hideharu; Hirakawa, Hideki; Shoji, Mikio; McBride, Mark J.; Rhodes, Ryan G.; Nakayama, Koji

2009-01-01

Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other Gram-negative bacteria are lacking in P. gingivalis, but several proteins, including PorT, have been linked to gingipain secretion. Comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. Six of these (PorK, PorL, PorM, PorN, PorW, and Sov) were similar in sequence to Flavobacterium johnsoniae gliding motility proteins, and two others (PorX and PorY) were putative two-component system regulatory proteins. Real-time RT-PCR analysis revealed that porK, porL, porM, porN, porP, porT, and sov were down-regulated in P. gingivalis porX and porY mutants. Disruption of the F. johnsoniae porT ortholog resulted in defects in motility, chitinase secretion, and translocation of a gliding motility protein, SprB adhesin, to the cell surface, providing a link between a unique protein translocation system and a motility apparatus in members of the Bacteroidetes phylum. PMID:19966289

Oxidative phosphorylation versus glycolysis: what fuel do spermatozoa use?

PubMed Central

du Plessis, Stefan S; Agarwal, Ashok; Mohanty, Gayatri; van der Linde, Michelle

2015-01-01

Spermatozoa are highly specialized cells. Adenosine triphosphate (ATP), which provides the energy for supporting the key functions of the spermatozoa, is formed by 2 metabolic pathways, namely glycolysis and oxidative phosphorylation (OXPHOS). It is produced in the mitochondria through OXPHOS as well as in the head and principal piece of the flagellum through glycolysis. However, there is a great discrepancy as to which method of ATP production is primarily utilized by the spermatozoa for successful fertilization. Mitochondrial respiration is considered to be a more efficient metabolic process for ATP synthesis in comparison to glycolysis. However, studies have shown that the diffusion potential of ATP from the mitochondria to the distal end of the flagellum is not sufficient to support sperm motility, suggesting that glycolysis in the tail region is the preferred pathway for energy production. It is suggested by many investigators that although glycolysis forms the major source of ATP along the flagellum, energy required for sperm motility is mainly produced during mitochondrial respiration. Nevertheless, some studies have shown that when glycolysis is inhibited, proper functioning and motility of spermatozoa remains intact although it is unclear whether such motility can be sustained for prolonged periods of time, or is sufficiently vigorous to achieve optimal fertilization. The purpose of this article is to provide an overview of mammalian sperm energy metabolism and identify the preferred metabolic pathway for ATP generation which forms the basis of energy production in human spermatozoa during fertilization. PMID:25475660

Oxidative phosphorylation versus glycolysis: what fuel do spermatozoa use?

PubMed

du Plessis, Stefan S; Agarwal, Ashok; Mohanty, Gayatri; van der Linde, Michelle

2015-01-01

Spermatozoa are highly specialized cells. Adenosine triphosphate (ATP), which provides the energy for supporting the key functions of the spermatozoa, is formed by 2 metabolic pathways, namely glycolysis and oxidative phosphorylation (OXPHOS). It is produced in the mitochondria through OXPHOS as well as in the head and principal piece of the flagellum through glycolysis. However, there is a great discrepancy as to which method of ATP production is primarily utilized by the spermatozoa for successful fertilization. Mitochondrial respiration is considered to be a more efficient metabolic process for ATP synthesis in comparison to glycolysis. However, studies have shown that the diffusion potential of ATP from the mitochondria to the distal end of the flagellum is not sufficient to support sperm motility, suggesting that glycolysis in the tail region is the preferred pathway for energy production. It is suggested by many investigators that although glycolysis forms the major source of ATP along the flagellum, energy required for sperm motility is mainly produced during mitochondrial respiration. Nevertheless, some studies have shown that when glycolysis is inhibited, proper functioning and motility of spermatozoa remains intact although it is unclear whether such motility can be sustained for prolonged periods of time, or is sufficiently vigorous to achieve optimal fertilization. The purpose of this article is to provide an overview of mammalian sperm energy metabolism and identify the preferred metabolic pathway for ATP generation which forms the basis of energy production in human spermatozoa during fertilization.

Surface association and the MreB cytoskeleton regulate pilus production, localization and function in Pseudomonas aeruginosa.

PubMed

Cowles, Kimberly N; Gitai, Zemer

2010-06-01

Spatial organization of bacterial proteins influences many cellular processes, including division, chromosome segregation and motility. Virulence-associated proteins also localize to specific destinations within bacterial cells. However, the functions and mechanisms of virulence factor localization remain largely unknown. In this work, we demonstrate that polar assembly of the Pseudomonas aeruginosa PAO1 type IV pilus is regulated by surface association in a manner that affects gene transcription, protein levels and protein localization. We also uncover one mechanism for this regulation that acts through the actin homologue MreB. Inactivation of MreB leads to mislocalization of the pilus retraction ATPase PilT, mislocalization of the pili themselves and a reduction in motility. Furthermore, the role of MreB in polar localization of PilT is modulated by surface association, corroborating our results that environmental factors influence the regulation of pilus production. Specifically, MreB mediates both the initiation and maintenance of PilT localization when cells are grown in suspension but only affects the initiation of localization when cells are grown on a surface. Together, these results suggest that the bacterial cytoskeleton provides a mechanism for the polar localization of P. aeruginosa pili and demonstrate that protein localization may represent an important aspect of virulence factor regulation in bacterial pathogens.

Sperm quality assessment via separation and sedimentation in a microfluidic device.

PubMed

Chen, Chang-Yu; Chiang, Tsun-Chao; Lin, Cheng-Ming; Lin, Shu-Sheng; Jong, De-Shien; Tsai, Vincent F-S; Hsieh, Ju-Ton; Wo, Andrew M

2013-09-07

A major reason for infertility is due to male factors, including the quality of spermatozoa, which is a primary factor and often difficult to assess, particularly the total sperm concentration and its motile percentage. This work presents a simple microfluidic device to assess sperm quality by quantifying both total and motile sperm counts. The key design feature of the microfluidic device is two channels separated by a permeative phase-guide structure, where one channel is filled with raw semen and the other with pure buffer. The semen sample was allowed to reach equilibrium in both chambers, whereas non-motile sperms remained in the original channel, and roughly half of the motile sperms would swim across the phase-guide barrier into the buffer channel. Sperms in each channel agglomerated into pellets after centrifugation, with the corresponding area representing total and motile sperm concentrations. Total sperm concentration up to 10(8) sperms per ml and motile percentage in the range of 10-70% were tested, encompassing the cutoff value of 40% stated by World Health Organization standards. Results from patient samples show compact and robust pellets after centrifugation. Comparison of total sperm concentration between the microfluidic device and the Makler chamber reveal they agree within 5% and show strong correlation, with a coefficient of determination of R(2) = 0.97. Motile sperm count between the microfluidic device and the Makler chamber agrees within 5%, with a coefficient of determination of R(2) = 0.84. Comparison of results from the Makler Chamber, sperm quality analyzer, and the microfluidic device revealed that results from the microfluidic device agree well with the Makler chamber. The sperm microfluidic chip analyzes both total and motile sperm concentrations in one spin, is accurate and easy to use, and should enable sperm quality analysis with ease.

Identification of sperm subpopulations with defined motility characteristics in ejaculates from Ile de France rams.

PubMed

Bravo, J A; Montanero, J; Calero, R; Roy, T J

2011-11-01

The aims of this study were to identify different motile sperm subpopulations in fresh ejaculates from six Ile de France rams, by using a computer-assisted sperm motility analysis (CASA) system, and to evaluate the effects of individual ram and season on population distribution. Overall sperm motility and individual kinematic parameters of motile spermatozoa were evaluated for 125,312 spermatozoa, defined by curvilinear velocity (VCL), linear velocity (VSL), average path velocity (VAP), linearity coefficient (LIN), straightness coefficient (STR), wobble coefficient (WOB), mean amplitude of lateral head displacement (ALH) and frequency of head displacement (BCF). A multivariate cluster analysis was carried out to classify these spermatozoa into a reduced number of subpopulations according to their movement patterns. The statistical analysis clustered the whole motile sperm population into five separate groups: subpopulation 1, constituted by rapid, progressive and non sinuous spermatozoa (VCL=126.41 μm/s, STR=92.87% and LIN=86.47%); subpopulation 2, characterized by progressive spermatozoa with moderate velocity (VCL=74.74 μm/s and STR=84.03%); subpopulation 3, represented by rapid, progressive and sinuous spermatozoa (VCL=130.45 μm/s, STR=76.02% and LIN=47.68%); subpopulation 4 represents rapid nonprogressive spermatozoa (VCL=128.69 μm/s and STR=44.09%); subpopulation 5 includes poorly motile, nonprogressive spermatozoa with a very irregular trajectory (VCL=36.81 μm/s and STR=47.04%). Our results show the existence of five subpopulations of motile spermatozoa in ram ejaculates. The frequency distribution of spermatozoa within subpopulations was quite similar for the six rams, and the five subpopulations turned out to be very stable along seasons. Copyright © 2011 Elsevier B.V. All rights reserved.

Daclatasvir inhibits hepatitis C virus NS5A motility and hyper-accumulation of phosphoinositides

PubMed Central

Chukkapalli, Vineela; Berger, Kristi L.; Kelly, Sean M.; Thomas, Meryl; Deiters, Alexander; Randall, Glenn

2014-01-01

Combinations of direct-acting antivirals (DAAs) against the hepatitis C virus (HCV) have the potential to revolutionize the HCV therapeutic regime. An integral component of DAA combination therapies are HCV NS5A inhibitors. It has previously been proposed that NS5A DAAs inhibit two functions of NS5A: RNA replication and virion assembly. In this study, we characterize the impact of a prototype NS5A DAA, daclatasvir (DCV), on HCV replication compartment formation. DCV impaired HCV replicase localization and NS5A motility. In order to characterize the mechanism behind altered HCV replicase localization, we examined the impact of DCV on the interaction of NS5A with its essential cellular cofactor, phosphatidylinositol-4-kinase III α (PI4KA). We observed that DCV does not inhibit PI4KA directly, nor does it impair early events of the NS5A-PI4KA interaction that can occur when NS5A is expressed alone. NS5A functions that are unaffected by DCV include PI4KA binding, as determined by co-immunoprecipitation, and a basal accumulation of the PI4KA product, PI4P. However, DCV impairs late steps in PI4KA activation that requires NS5A expressed in the context of the HCV polyprotein. These NS5A functions include hyper-stimulation of PI4P levels and appropriate replication compartment formation. The data are most consistent with a model wherein DCV inhibits conformational changes in the NS5A protein or protein complex formations that occur in the context of HCV polyprotein expression and stimulate PI4P hyper-accumulation and replication compartment formation. PMID:25546252

Spontaneous mutations in the flhD operon generate motility heterogeneity in Escherichia coli biofilm.

PubMed

Horne, Shelley M; Sayler, Joseph; Scarberry, Nicholas; Schroeder, Meredith; Lynnes, Ty; Prüß, Birgit M

2016-11-08

Heterogeneity and niche adaptation in bacterial biofilm involve changes to the genetic makeup of the bacteria and gene expression control. We hypothesized that i) spontaneous mutations in the flhD operon can either increase or decrease motility and that ii) the resulting motility heterogeneity in the biofilm might lead to a long-term increase in biofilm biomass. We allowed the highly motile E. coli K-12 strain MC1000 to form seven- and fourteen-day old biofilm, from which we recovered reduced motility isolates at a substantially greater frequency (5.4 %) than from a similar experiment with planktonic bacteria (0.1 %). Biofilms formed exclusively by MC1000 degraded after 2 weeks. In contrast, biofilms initiated with a 1:1 ratio of MC1000 and its isogenic flhD::kn mutant remained intact at 4 weeks and the two strains remained in equilibrium for at least two weeks. These data imply that an 'optimal' biofilm may contain a mixture of motile and non-motile bacteria. Twenty-eight of the non-motile MC1000 isolates contained an IS1 element in proximity to the translational start of FlhD or within the open reading frames for FlhD or FlhC. Two isolates had an IS2 and one isolate had an IS5 in the open reading frame for FlhD. An additional three isolates contained deletions that included the RNA polymerase binding site, five isolates contained point mutations and small deletions in the open reading frame for FlhC. The locations of all these mutations are consistent with the lack of motility and further downstream within the flhD operon than previously published IS elements that increased motility. We believe that the location of the mutation within the flhD operon determines whether the effect on motility is positive or negative. To test the second part of our hypothesis where motility heterogeneity in a biofilm may lead to a long-term increase in biofilm biomass, we quantified biofilm biomass by MC1000, MC1000 flhD::kn, and mixtures of the two strains at ratios of 1:1, 10:1, and 1:10. After 3 weeks, biofilm of the mixed cultures contained up to five times more biomass than biofilm of each of the individual strains. Mutations in the flhD operon can exert positive or negative effects on motility, depending on the site of the mutation. We believe that this is a mechanism to generate motility heterogeneity within E. coli biofilm, which may help to maintain biofilm biomass over extended periods of time.

Integration of the Second Messenger c-di-GMP into the Chemotactic Signaling Pathway

PubMed Central

Russell, Matthew H.; Bible, Amber N.; Fang, Xin; Gooding, Jessica R.; Campagna, Shawn R.; Gomelsky, Mark; Alexandre, Gladys

2013-01-01

ABSTRACT Elevated intracellular levels of the bacterial second messenger c-di-GMP are known to suppress motility and promote sessility. Bacterial chemotaxis guides motile cells in gradients of attractants and repellents over broad concentration ranges, thus allowing bacteria to quickly adapt to changes in their surroundings. Here, we describe a chemotaxis receptor that enhances, as opposed to suppresses, motility in response to temporary increases in intracellular c-di-GMP. Azospirillum brasilense’s preferred metabolism is adapted to microaerophily, and these motile cells quickly navigate to zones of low oxygen concentration by aerotaxis. We observed that changes in oxygen concentration result in rapid changes in intracellular c-di-GMP levels. The aerotaxis and chemotaxis receptor, Tlp1, binds c-di-GMP via its C-terminal PilZ domain and promotes persistent motility by increasing swimming velocity and decreasing swimming reversal frequency, which helps A. brasilense reach low-oxygen zones. If c-di-GMP levels remain high for extended periods, A. brasilense forms nonmotile clumps or biofilms on abiotic surfaces. These results suggest that association of increased c-di-GMP levels with sessility is correct on a long-term scale, while in the short-term c-di-GMP may actually promote, as opposed to suppress, motility. Our data suggest that sensing c-di-GMP by Tlp1 functions similar to methylation-based adaptation. Numerous chemotaxis receptors contain C-terminal PilZ domains or other sensory domains, suggesting that intracellular c-di-GMP as well as additional stimuli can be used to modulate adaptation of bacterial chemotaxis receptors. PMID:23512960

The beneficial effect of genetically engineered Schwann cells with enhanced motility in peripheral nerve regeneration: review.

PubMed

Gravvanis, A I; Lavdas, A A; Papalois, A; Tsoutsos, D A; Matsas, R

2007-01-01

The importance of Schwann cells in promoting nerve regeneration across a conduit has been extensively reported in the literature, and Schwann cell motility has been acknowledged as a prerequisite for myelination of the peripheral nervous system during regeneration after injury. Review of recent literature and retrospective analysis of our studies with genetically modified Schwann Cells with increased motility in order to identify the underlying mechanism of action and outline the future trends in peripheral nerve repair. Schwann cell transduction with the pREV-retrovirus, for expression of Sialyl-Transferase-X, resulting in conferring Polysialyl-residues (PSA) on NCAM, increases their motility in-vitro and ensures nerve regeneration through silicone tubes after end-to-side neurorraphy in the rat sciatic nerve model, thus significantly promoting fiber maturation and functional outcome. An artificial nerve graft consisting of a type I collagen tube lined with the genetically modified Schwann cells with increased motility, used to bridge a defect in end-to-end fashion in the rat sciatic nerve model, was shown to promote nerve regeneration to a level equal to that of a nerve autograft. The use of genetically engineered Schwann cells with enhanced motility for grafting endoneural tubes promotes axonal regeneration, by virtue of the interaction of the transplanted cells with regenerating axonal growth cones as well as via the recruitment of endogenous Schwann cells. It is envisaged that mixed populations of Schwann cells, expressing PSA and one or more trophic factors, might further enhance the regenerating and remyelinating potential of the lesioned nerves.

The effect of Tribulus terrestris extract on motility and viability of human sperms after cryopreservation.

PubMed

Asadmobini, Atefeh; Bakhtiari, Mitra; Khaleghi, Sara; Esmaeili, Farzaneh; Mostafaei, Ali

2017-04-01

Semen cryopreservation produces significant amounts of reactive oxygen species (ROS), which may lead to impairment of sperm morphology, function, and ultimately, male fertility. Since Tribulus terrestris has antioxidant and free-radical-scavenging properties, this study aims to reveal the effect of the Tribulus terrestris extract on motility and vitality of human sperms after cryopreservation. Semen specimens from 80 healthy volunteers were divided into eight groups: fresh control (group I), freeze control (group II), groups III, IV, and V, which had 20, 40, and 50 μg/mL doses of Tribulus terrestris extract added before cryopreservation, and groups VI, VII, and VIII, which were supplemented by these extract doses after the freeze-thaw process. To evaluate the effects of the Tribulus terrestris extract, the semen samples were incubated with the extract and evaluated with a light microscope for motility and viability. After cryopreservation, a significant improvement in spermatozoa viability was observed in group VII. In groups VII and VIII, motility, according to World Health Organization (WHO) criteria, increased considerably (p < 0.001). There was no significant difference among groups III, IV, and V. The present study demonstrated that the protective effects of Tribulus terrestris, which improves human sperm motility and viability, may be due to its antioxidant properties. On the basis of the results, the researchers concluded that Tribulus terrestris can be used as a safe therapeutic alternative to current modalities for the management of motility dysfunction in males. Copyright © 2017 Elsevier Inc. All rights reserved.

Prediction of the fertility of stallion frozen-thawed semen using a combination of computer-assisted motility analysis, microscopical observation and flow cytometry.

PubMed

Battut, I Barrier; Kempfer, A; Lemasson, N; Chevrier, L; Camugli, S

2017-07-15

Spermatozoa from some stallions do not maintain an acceptable fertility after freezing and thawing. The selection of frozen ejaculates that would be suitable for insemination is mainly based on post-thaw motility, but the prediction of fertility remains limited. A recent study in our laboratory has enabled the determination of a new protocol for the evaluation of fresh stallion semen, combining microscopical observation, computer-assisted motility analysis and flow cytometry, and providing a high level of fertility prediction. The purpose of the present experiment was to perform similar investigations on frozen semen. A panel of tests evaluating a large number of compartments or functions of the spermatozoa was applied to a population of 42 stallions, 33 of which showing widely differing fertilities (17-67% pregnancy rate per cycle [PRC]). Variability was evaluated by calculating the coefficient of variation (CV=SD/mean) and the intra-class correlation or "repeatability" for each variable. For paired variables, mean within-stallion CV% was significantly lower than between-stallion CV%, which was significantly lower than total CV%. Within-ejaculate repeatability, determined by analysing 6 straws for each of 10 ejaculates, ranged from 0.60 to 0.97. Within-stallion repeatability, determined by analysing at least 5 ejaculates for each of 38 stallions, ranged from 0.12 to 0.95. Principal component regression using a combination of 25 variables, including motility, morphology, viability, oxidation level, acrosome integrity, DNA integrity and hypoosmotic resistance, accounted for 94.5% of the variability regarding fertility, and was used to calculate a prediction of the PRC with a mean standard deviation of 2.2. The difference between the observed PRC and the calculated value ranged from -3.4 to 4.2. The 90% confidence interval (90CI) for the prediction of the PRC for the stallions of unknown fertility ranged from 8 to 30 (mean = 17). The best-fit model using only motility variables, evaluated after 10 min at 36 °C and 2 h at 36 °C or room temperature, accounted for only 74.2% of the variability. The difference between the observed PRC and the calculated value ranged from -7.2 to 14. The 90CI for the prediction of the PRC for the stallions of unknown fertility ranged from 23 to 48 (mean = 33). In conclusion, this study demonstrated that an appropriate combination of computer-assisted motility analysis, microscopical observation and flow cytometry can provide a higher prediction of fertility than motility analysis alone. Copyright © 2017 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geng, Tao; Smallwood, Chuck R.; Bredeweg, Erin L.

Modern live-cell imaging approaches permit real-time visualization of biological processes, yet limitations exist for unicellular organism isolation, culturing and long-term imaging that preclude fully understanding how cells sense and respond to environmental perturbations and the link between single-cell variability and whole-population dynamics. Here we present a microfluidic platform that provides fine control over the local environment with the capacity to replace media components at any experimental time point, and provides both perfused and compartmentalized cultivation conditions depending on the valve configuration. The functionality and flexibility of the platform were validated using both bacteria and yeast having different sizes, motility andmore » growth media. The demonstrated ability to track the growth and dynamics of both motile and non-motile prokaryotic and eukaryotic organisms emphasizes the versatility of the devices, which with further scale-up should enable studies in bioenergy and environmental research.« less

Bacterial accumulation in viscosity gradients

NASA Astrophysics Data System (ADS)

Waisbord, Nicolas; Guasto, Jeffrey

2016-11-01

Cell motility is greatly modified by fluid rheology. In particular, the physical environments in which cells function, are often characterized by gradients of viscous biopolymers, such as mucus and extracellular matrix, which impact processes ranging from reproduction to digestion to biofilm formation. To understand how spatial heterogeneity of fluid rheology affects the motility and transport of swimming cells, we use hydrogel microfluidic devices to generate viscosity gradients in a simple, polymeric, Newtonian fluid. Using video microscopy, we characterize the random walk motility patterns of model bacteria (Bacillus subtilis), showing that both wild-type ('run-and-tumble') cells and smooth-swimming mutants accumulate in the viscous region of the fluid. Through statistical analysis of individual cell trajectories and body kinematics in both homogeneous and heterogeneous viscous environments, we discriminate passive, physical effects from active sensing processes to explain the observed cell accumulation at the ensemble level.

Self-organized cell motility

NASA Astrophysics Data System (ADS)

Du, Xinxin; Doubrovinski, Konstantin

2011-03-01

Cell migration plays a key role in a wide range of biological phenomena, such as morphogenesis, chemotaxis, and wound healing. Cell locomotion relies on the cytoskeleton, a meshwork of filamentous proteins, intrinsically out of thermodynamic equilibrium and cross-linked by molecular motors, proteins that turn chemical energy into mechanical work. In the course of locomotion, cells remain polarized, i.e. they retain a single direction of motion in the absence of external cues. Traditionally, polarization has been attributed to intracellular signaling. However, recent experiments show that polarization may be a consequence of self-organized cytoskeletal dynamics. Our aim is to elucidate the mechanisms by which persistent unidirectional locomotion may arise through simple mechanical interactions of the cytoskeletal proteins. To this end, we develop a simple physical description of cytoskeletal dynamics. We find that the proposed description accounts for a range of phenomena associated with cell motility, including spontaneous polarization, persistent unidirectional motion, and the co-existence of motile and non-motile states.

Mitochondrial outer membrane permeabilization increases reactive oxygen species production and decreases mean sperm velocity but is not associated with DNA fragmentation in human sperm.

PubMed

Treulen, F; Uribe, P; Boguen, R; Villegas, J V

2016-02-01

Does induction of mitochondrial outer membrane permeabilization (MOMP) in vitro affect specific functional parameters of human spermatozoa? Our findings show that MOMP induction increases intracellular reactive oxygen species (ROS) and decreases mean sperm velocity but does not alter DNA integrity. MOMP in somatic cells is related to a variety of apoptotic traits, such as alteration of mitochondrial membrane potential (ΔΨm), and increase in ROS production and DNA fragmentation. Although the presence of these apoptotic features has been reported in spermatozoa, to date the effects of MOMP on sperm function and DNA integrity have not been analysed. The study included spermatozoa from fertile donors. Motile sperm were obtained using the swim-up method. The highly motile sperm were collected and diluted with human tubal fluid to a final cell concentration of 5 × 10(6) ml(-1). To induce MOMP, selected sperm were treated at 37°C for 4 h with a mimetic of a Bcl-2 pro-apoptotic protein, ABT-737. MOMP was evaluated by relocating of cytochrome c. In addition, the effect of ABT-737 on mitochondrial inner membrane permeabilization was assessed using the calcein-AM/cobalt chloride method. In turn, ΔΨm was evaluated with JC-1 staining, intracellular ROS production with dihydroethidium, sperm motility was analysed by computer-assisted sperm analysis and DNA fragmentation by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) assay. Measurements were performed by flow cytometry. MOMP was associated with ΔΨm dissipation (P < 0.05), increased ROS production (P < 0.05) and decreased mean sperm velocity (P < 0.05), but it was not associated with DNA fragmentation. MOMP did not induce a large increase in ROS, which could explain the negligible effect of MOMP on sperm DNA fragmentation under our experimental conditions. The study was carried out in vitro using highly motile sperm, selected by swim-up, from healthy donors. The results obtained in this study reveal that the alterations of sperm functions caused by MOMP are sufficiently relevant to justify its future study in male infertility. None. The study was funded by grant DI12-0102 from the Universidad de La Frontera (J.V.V.) and a doctoral scholarship from CONICYT (F.T.). The authors declare no conflict of interest. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Assaying Wnt5A-mediated Invasion in Melanoma Cells

PubMed Central

O'Connell, Michael P.; French, Amanda D.; Leotlela, Poloko D.; Weeraratna, Ashani T.

2009-01-01

Wnt5A has been implicated in melanoma metastasis, and the progression of other cancers including pancreatic, gastric, prostate and lung cancers. Assays to test motility and invasion include both in vivo assays, and in vitro assays. The former assays include the use of tail vein or footpad injections of metastatic cells, and are often laborious and expensive. In vitro invasion assays provide quick readouts that can help to establish conditions that either activate or inhibit melanoma cell motility, and to assess whether the conditions in question are worth translating into an in vivo model. Here we describe two standard methods for assaying motility and invasion in vitro including wound healing assays and Matrigel invasion assays (Boyden chamber assays). In addition, we and several other laboratories have previously shown that melanoma cells require MMP-2 for their invasion, and have recently shown that Wnt5A treatment can increase the levels of this enzyme in melanoma cells, as demonstrated by gelatin zymography. The use of these techniques can help to assess the migratory capacity of melanoma cells in response to Wnt treatment. PMID:19099260

[Effects on the regional homogeneity of resting-state brain function in the healthy subjects of gastric distention treated with acupuncture at the front-mu and back-shu points of the stomach, Weishu (BL 21) and Zhongwan (CV 12)].

PubMed

Cai, Ronglin; Guan, Yuanyuan; Wu, Hongli; Xu, Chunsheng; Li, Chuanfu; Hu, Ling; Shen, Guoming

2018-04-12

To observe the regional homogeneity (ReHo) of resting-state brain function in the healthy subjects of gastric distention treated with acupuncture at the back- shu and front- mu points of the stomach, Weishu (BL 21) and Zhongwan (CV 12) and the correlation with gastric motility so as to explore the mechanism on the central integration of the front- mu and back- shu points of the stomach. The crossover test design was adopted. Twenty-four healthy subjects were assigned to a Weishu group, a Zhongwan group and a combined-point group separately, 8 cases in each one in each of the three times. Totally, 24 subjects were included in each group. Under the water load condition, the subjects received acupuncture at Weishu (BL 21), Zhongwan (CV 12) and the combined Weishu (BL 21) and Zhongwan (CV 12). Before and after each acupuncture, the resting-state brain functional magnetic resonance imaging (fMRI) scan and electrogastrogram (EGG) test were applied. The ReHo value was calculated in the collected fMRI imaging data. The changes in ReHo values were analyzed and compared before and after acupuncture in each group, as well as among the groups. The gastric motility was analyzed before and after acupuncture. Additionally, the correlative analysis was conducted between the gastric motility and ReHo changes before and after acupuncture. (1) After acupuncture, EGG amplitudes in the subjects of each group were lower remarkably as compared with those before acupuncture (all P <0.01). The EGG frequencies were not different significantly as compared with those before acupuncture (all P >0.05). The EGG amplitudes in the Weishu group and the Zhongwan group were higher than those in the combined-point group (both P <0.05). (2) As compared with the conditions before acupuncture, acupuncture at the combined front- mu and the back- shu points as well as Weishu (BL 21) and Zhongwan (CV 12) separately all induced the changes in the brain ReHo. Acupuncture at the combined front- mu and the back- shu points significantly increased Reho values in the right inferior temporal gyrus, the left thalamus, the precuneus and the posterior cingulate gyrus (all P <0.05) and remarkably reduced the ReHo values in the the middle temporal gyrus of the right temporal pole, sulcus calcarinus and precuneus (all P <0.05). Compared with the single point groups, acupuncture at the combined front- mu and the back- shu points induced the increase of ReHo value in the posterior cingulate gyrus and the decrease of ReHo in the temporal pole (all P <0.05). (3) The correlative analysis showed that the changes in the ReHo values in the posterior cingulate gyrus, the thalamus and the precuneus were positively correlated to the changes of the gastric motility amplitudes. The changes in the ReHo values in the temporal pole was negatively correlated to the changes of the gastric motility amplitudes. Acupuncture at the combined back- shu and front- mu points of the stomach, as well as acupuncture at single Weishu (BL 21) and Zhongwan (CV 12) induce the ReHo changes in the different brain regions. Acupuncture at the combined back- shu and front- mu points of the stomach may induce the ReHo changes in some new brain regions as compared with the acupuncture at the single point. The thalamus, the posterior cingulate gyrus and the precuneus may be the the important integrated brain regions for acupuncture at the back- shu and the front- mu points in regulating the gastric motility. The effects of acupuncture at the back- shu and the front- mu points for the regulation of the gastric motility are closely related to the thalamus, the limbic system and the default network of the brain regions.

Effects of advanced glycation end products on ezrin-dependent functions in LLC-PK1 proximal tubule cells.

PubMed

Bach, Leon A; Gallicchio, Marisa A; McRobert, E Anne; Tikoo, Anjali; Cooper, Mark E

2005-06-01

We have recently shown that advanced glycation products (AGEs) bind to the ERM (ezrin, radixin, moesin) family of proteins. ERM proteins act as cross-linkers between cell membrane proteins and the actin cytoskeleton. They are also involved in signal transduction pathways. They therefore have a critical role in normal cell processes, including modulation of cell shape, adhesion, and motility. We postulate that AGEs may contribute to diabetic complications by disrupting ERM function. In support of this hypothesis, AGEs inhibit ezrin-dependent tubulogenesis of proximal tubule cells. Phosphorylation is an important activating mechanism for ERM proteins, and AGEs inhibit ezrin phosphorylation mediated by the epidermal growth factor receptor.

Novel disposable transnasal endoscopy for assessment of esophageal motor function.

PubMed

Lim, Chul-Hyun; Choi, Myung-Gyu; Baeg, Myong-Ki; Moon, Sung Jin; Kim, Jin Su; Cho, Yu Kyung; Park, Jae Myung; Lee, In Seok; Kim, Sang Woo; Choi, Kyu Yong

2014-01-01

A novel disposable transnasal endoscopy (DTE) with a portable system has been developed to provide unsedated esophagoscopy by modifying capsule endoscopy. The aim of this study was to assess the feasibility of DTE to evaluate esophageal motor function. Patients with or suspected esophageal motility disorders and healthy volunteers were enrolled. Participants underwent esophageal high-resolution manometry and DTE in random order on different days. Motility was observed with DTE at 1, 8, and 16 cm above the gastroesophageal junction. Twenty healthy volunteers and 20 symptomatic subjects participated (8 achalasia, 5 scleroderma, 3 diffuse esophageal spasm, 1 hypertensive peristalsis, 1 peristaltic dysfunction, and 22 normal esophageal function). The normal findings on DTE were as follows. As the subject swallowed water, swallow-induced relaxation with elevation of the lower esophageal sphincter caused the endoscope to cross the Z-line into the gastric lumen. After the passage of water and air, complete closure of the lower esophageal sphincter occurred, with the return of the endoscope to its previous position. During the resting stage of the esophageal body, an air bubble could be seen in the center of the radially wrinkled and occluded lumen. The endoscopic diagnosis was in agreement with the clinical diagnosis in all but 2. Most of the participants reported acceptable discomfort during DTE and 62.5% of the subjects preferred DTE to manometry. DTE can accurately characterize normal esophageal motor function, allowing the diagnosis of esophageal motility disorders. DTE has potential widespread applications, especially in outpatient clinics.

Nicotine behavioral pharmacology: clues from planarians

PubMed Central

Rawls, Scott M.; Patil, Tanvi; Tallarida, Christopher S.; Baron, Steven; Kim, Myongji; Song, Kevin; Ward, Sara; Raffa, Robert B.

2011-01-01

Background Nicotine is one of the world’s most addictive substances and the primary reason that humans inhale tobacco smoke. The pharmacological effects of nicotine can be investigated in planarians, aquatic flatworms that possess an integrated neural network including cephalic ganglia that some consider the earliest “brain” and spinal cord. Here, we tested the hypothesis that nicotine exposure elicits mammalian-like behaviors in planarians. Methods Planarian motility and stereotypy (C-shape hyperkinesias) were quantified following acute nicotine exposure. During repeated nicotine exposure, we investigated the presence of withdrawal, tolerance, behavioral sensitization, and environmental place conditioning. Results Acute nicotine exposure increased stereotypical activity and elicited biphasic effects on motility. A low concentration (0.01 mM) increased motility whereas higher concentrations (0.3 – 10 mM) elicited the opposite effect. Planarians exposed to nicotine (0.03 mM) for 60 min and then tested in water displayed reduced motility that was not observed during exposure to water, acute nicotine, or continuous nicotine. Nicotine-treated planarians withdrawn from the drug for 3 days before being challenged with nicotine displayed behavioral sensitization at low concentrations (0.1, 0.3 mM) but tolerance at higher concentrations (1, 3 mM). Planarians conditioned with nicotine in the ambient light (non-preferred environment) displayed a reduction in their natural preference for a dark environment. Conclusions The present results suggest nicotine elicits mammalian-like effects in planarians, including decreased motility and increased stereotypy following acute administration and abstinence-induced withdrawal, behavioral sensitization, tolerance, and place conditioning during repeated exposure. PMID:21530106

Semen quality in adult male survivors 5 years after the 2008 Wenchuan earthquake.

PubMed

Chen, X M; Chen, S M; Yue, H X; Lin, L; Wu, Y B; Liu, B; Jiang, M; Ma, Y X

2016-12-01

The influence of the Wenchuan earthquake on semen quality of adult male survivors is unclear. We investigated the semen quality included 673 male survivors from the worse-affected counties in the earthquake between Aug 2008 and July 2013. Semen parameters including pH, volume, concentration, motility and morphology were measured according to the World Health Organization (WHO) criteria. Kruskal-Wallis analysis of variance was used to examine the statistical differences between years, and a logistic regression was used to analyse the impacts caused by earthquake on the changes of semen quality. We found the medians (5th and 95th) were 2.5 ml (0.6-5.5) for semen volume, 59.0 × 10 6  ml -1 [(13.0-133.0)] × 10 6  ml -1 for semen concentration, 46% (13-64%) for sperm progressive motility and 3.0% (0-17.5%) for normal morphology for adult male survivors. Semen concentration, the percentage of sperm progressive motility, total motility and sperm normal morphology were all decreased in the first 3 years, and the differences among years 1, 2 and 3 were significant except the percentage of sperm progressive motility (P < 0.05). The casualties and heavy housing damage caused by earthquake had a negative effect on semen quality. The main findings will provide further diagnosis and therapy basis of male fertility by data, for affected populations in the earthquake. © 2016 Blackwell Verlag GmbH.

Lateral Membrane Waves Constitute a Universal Dynamic Pattern of Motile Cells

NASA Astrophysics Data System (ADS)

Döbereiner, Hans-Günther; Dubin-Thaler, Benjamin J.; Hofman, Jake M.; Xenias, Harry S.; Sims, Tasha N.; Giannone, Grégory; Dustin, Michael L.; Wiggins, Chris H.; Sheetz, Michael P.

2006-07-01

We have monitored active movements of the cell circumference on specifically coated substrates for a variety of cells including mouse embryonic fibroblasts and T cells, as well as wing disk cells from fruit flies. Despite having different functions and being from multiple phyla, these cell types share a common spatiotemporal pattern in their normal membrane velocity; we show that protrusion and retraction events are organized in lateral waves along the cell membrane. These wave patterns indicate both spatial and temporal long-range periodic correlations of the actomyosin gel.

Effects of transforming growth factor-beta1 on cell motility, collagen gel contraction, myofibroblastic differentiation, and extracellular matrix expression of human adipose-derived stem cell.

PubMed

Kakudo, Natsuko; Kushida, Satoshi; Suzuki, Kenji; Ogura, Tsunetaka; Notodihardjo, Priscilla Valentin; Hara, Tomoya; Kusumoto, Kenji

2012-12-01

Human adipose-derived stem cells (ASCs) are adult pluripotent stem cells, and their usefulness in plastic surgery has garnered attention in recent years. Although, there have been expectations that ASCs might function in wound repair and regeneration, no studies to date have examined the role of ASCs in the mechanism that promotes wound-healing. Transforming growth factor-beta1 (TGF-β1) is a strong candidate cytokine for the triggering of mesenchymal stem cell migration, construction of extracellular matrices, and differentiation of ASCs into myofibroblasts. Cell proliferation, motility, and differentiation, as well as extracellular matrix production, play an important role in wound-healing. We have evaluated the capacity of ASCs to proliferate and their potential to differentiate into phenotypic myofibroblasts, as well as their cell motility and collagen gel contraction ability, when cultured with TGF-β1. Cell motility was analyzed using a wound-healing assay. ASCs that differentiated into myofibroblasts expressed the gene for alpha-smooth muscle actin, and its protein expression was detected immunohistochemically. The extracellular matrix expression in ASCs was evaluated using real-time RT-PCR. Based on the results, we conclude that human ASCs have the potential for cell motility, extracellular matrix gene expression, gel contraction, and differentiation into myofibroblasts and, therefore, may play an important role in the wound-healing process.

Autocrine regulation of human sperm motility by tachykinins

PubMed Central

2010-01-01

Background We examined the presence and function of tachykinins and the tachykinin-degrading enzymes neprilysin (NEP) and neprilysin-2 (NEP2) in human spermatozoa. Methods Freshly ejaculated semen was collected from forty-eight normozoospermic human donors. We analyzed the expression of substance P, neurokinin A, neurokinin B, hemokinin-1, NEP and NEP2 in sperm cells by reverse-transcriptase polymerase chain reaction (RT-PCR), western blot and immunocytochemistry assays and evaluated the effects of the neprilysin and neprilysin-2 inhibitor phosphoramidon on sperm motility in the absence and presence of tachykinin receptor-selective antagonists. Sperm motility was measured using WHO procedures or computer-assisted sperm analysis (CASA). Results The mRNAs of the genes that encode substance P/neurokinin A (TAC1), neurokinin B (TAC3), hemokinin-1 (TAC4), neprilysin (MME) and neprilysin-2 (MMEL1) were expressed in human sperm. Immunocytochemistry studies revealed that tachykinin and neprilysin proteins were present in spermatozoa and show specific and differential distributions. Phosphoramidon increased sperm progressive motility and its effects were reduced in the presence of the tachykinin receptor antagonists SR140333 (NK1 receptor-selective) and SR48968 (NK2 receptor-selective) but unmodified in the presence of SR142801 (NK3 receptor-selective). Conclusion These data show that tachykinins are present in human spermatozoa and participate in the regulation of sperm motility. Tachykinin activity is regulated, at least in part, by neprilysins. PMID:20796280

Autocrine regulation of human sperm motility by tachykinins.

PubMed

Pinto, Francisco M; Ravina, Cristina G; Subiran, Nerea; Cejudo-Román, Antonio; Fernández-Sánchez, Manuel; Irazusta, Jon; Garrido, Nicolas; Candenas, Luz

2010-08-26

We examined the presence and function of tachykinins and the tachykinin-degrading enzymes neprilysin (NEP) and neprilysin-2 (NEP2) in human spermatozoa. Freshly ejaculated semen was collected from forty-eight normozoospermic human donors. We analyzed the expression of substance P, neurokinin A, neurokinin B, hemokinin-1, NEP and NEP2 in sperm cells by reverse-transcriptase polymerase chain reaction (RT-PCR), western blot and immunocytochemistry assays and evaluated the effects of the neprilysin and neprilysin-2 inhibitor phosphoramidon on sperm motility in the absence and presence of tachykinin receptor-selective antagonists. Sperm motility was measured using WHO procedures or computer-assisted sperm analysis (CASA). The mRNAs of the genes that encode substance P/neurokinin A (TAC1), neurokinin B (TAC3), hemokinin-1 (TAC4), neprilysin (MME) and neprilysin-2 (MMEL1) were expressed in human sperm. Immunocytochemistry studies revealed that tachykinin and neprilysin proteins were present in spermatozoa and show specific and differential distributions. Phosphoramidon increased sperm progressive motility and its effects were reduced in the presence of the tachykinin receptor antagonists SR140333 (NK1 receptor-selective) and SR48968 (NK2 receptor-selective) but unmodified in the presence of SR142801 (NK3 receptor-selective). These data show that tachykinins are present in human spermatozoa and participate in the regulation of sperm motility. Tachykinin activity is regulated, at least in part, by neprilysins.

Ocular Manifestations of Noonan Syndrome: A Prospective Clinical and Genetic Study of 25 Patients.

PubMed

van Trier, Dorothée C; Vos, Anna M C; Draaijer, Renske W; van der Burgt, Ineke; Draaisma, Jos M Th; Cruysberg, Johannes R M

2016-10-01

To determine the full spectrum of ocular manifestations in patients with Noonan syndrome (NS). Prospective cross-sectional clinical and genetic study in a tertiary referral center. Twenty-five patients with NS (mean age, 14 years; range, 8 months-25 years) clinically diagnosed by validated criteria. All patients were examined by the same team following a detailed study protocol. Genetic analyses were performed in 23 patients. Ocular abnormalities of vision and refraction, external ocular features, ocular position and motility, anterior segment, posterior segment, and intraocular pressure. Ocular features of vision and refraction were amblyopia (32%), myopia (40%), and astigmatism (52%). External ocular features were epicanthic folds (84%), hypertelorism (68%), ptosis (56%), high upper eyelid crease (64%), lower eyelid retraction (60%), abnormal upward slanting palpebral fissures (36%), downward slanting palpebral fissures (32%), and lagophthalmos (28%). Orthoptic abnormalities included strabismus (40%), abnormal stereopsis (44%), and limited ocular motility (40%). Anterior segment abnormalities included prominent corneal nerves (72%) and posterior embryotoxon (32%). Additional ocular features were found, including nonglaucomatous optic disc excavation (20%), relatively low (<10 mmHg) intraocular pressure (22%), and optic nerve hypoplasia (4%). Mutations were established in 22 patients: 19 PTPN11 mutations (76%), 1 SOS1 mutation, 1 BRAF mutation, and 1 KRAS mutation. The patient with the highest number of prominent corneal nerves had an SOS1 mutation. The patient with the lowest visual acuity, associated with bilateral optic nerve hypoplasia, had a BRAF mutation. Patients with severe ptosis and nearly total absence of levator muscle function had PTPN11 mutations. All patients showed at least 3 ocular features (range, 3-13; mean, 7), including at least 1 external ocular feature in more than 95% of the patients. Noonan syndrome is a clinical diagnosis with multiple genetic bases associated with an extensive variety of congenital ocular abnormalities. Ocular features of NS are characterized by 1 or more developmental anomalies of the eyelids (involving the position, opening, and closure) associated with various other ocular abnormalities in childhood, including amblyopia, myopia, astigmatism, strabismus, limited ocular motility, prominent corneal nerves, and posterior embryotoxon. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Regulation of Microglia by Ionotropic Glutamatergic and GABAergic Neurotransmission

PubMed Central

Wong, Wai T.; Wang, Minhua; Li, Wei

2015-01-01

Recent studies have indicated that constitutive functions of microglia in the healthy adult CNS involve immune surveillance, synapse maintenance, and trophic support. These functions have been related to the ramified structure of “resting” microglia and the prominent motility in their processes that provide extensive coverage of the entire extracellular milleu. In this review, we examine how external signals, and in particular, ionotropic neurotransmission, regulate features of microglial morphology and process motility. Taken together, current findings indicate that microglial physiology in the healthy CNS is constitutively and reciprocally regulated by endogenous ionotropic glutamatergic and GABAergic neurotransmission. These influences do not act directly on microglial cells but indirectly via the activity-dependent release of ATP, likely through a mechanism involving pannexin channels. Microglia in the “resting” state are not only dynamically active, but are constantly engaged in ongoing communication with neuronal and macroglial components of the CNS in a functionally relevant way. PMID:22166726

Metallic Glass Wire Based Localization of Kinesin/Microtubule Bio-molecular Motility System

NASA Astrophysics Data System (ADS)

Kim, K.; Sikora, A.; Yaginuma, S.; Nakayama, K. S.; Nakazawa, H.; Umetsu, M.; Hwang, W.; Teizer, W.

2014-03-01

We report electrophoretic accumulation of microtubules along metallic glass (Pd42.5Cu30Ni7.5P20) wires free-standing in solution. Microtubules are dynamic cytoskeletal filaments. Kinesin is a cytoskeletal motor protein. Functions of these bio-molecules are central to various dynamic cellular processes. Functional artificial organization of bio-molecules is a prerequisite for transferring their native functions into device applications. Fluorescence microscopy at the individual-microtubule level reveals microtubules aligning along the wire axis during the electrophoretic migration. Casein-treated electrodes are effective for releasing trapped microtubules upon removal of the external field. Furthermore, we demonstrate gliding motion of microtubules on kinesin-treated metallic glass wires. The reversible manner in the local adsorption of microtubules, the flexibility of wire electrodes, and the compatibility between the wire electrode and the bio-molecules are beneficial for spatio-temporal manipulation of the motility machinery in 3 dimensions.

Unique Directional Motility of Influenza C Virus Controlled by Its Filamentous Morphology and Short-Range Motions.

PubMed

Sakai, Tatsuya; Takagi, Hiroaki; Muraki, Yasushi; Saito, Mineki

2018-01-15

Influenza virus motility is based on cooperation between two viral spike proteins, hemagglutinin (HA) and neuraminidase (NA), and is a major determinant of virus infectivity. To translocate a virus particle on the cell surface, HA molecules exchange viral receptors and NA molecules accelerate the receptor exchange of HA. This type of virus motility was recently identified in influenza A virus (IAV). To determine if other influenza virus types have a similar receptor exchange mechanism-driven motility, we investigated influenza C virus (ICV) motility on a receptor-fixed glass surface. This system excludes receptor mobility, which makes it more desirable than a cell surface for demonstrating virus motility by receptor exchange. Like IAV, ICV was observed to move across the receptor-fixed surface. However, in contrast to the random movement of IAV, a filamentous ICV strain, Ann Arbor/1/50 (AA), moved in a straight line, in a directed manner, and at a constant rate, whereas a spherical ICV strain, Taylor/1233/47 (Taylor), moved randomly, similar to IAV. The AA and Taylor viruses each moved with a combination of gradual (crawling) and rapid (gliding) motions, but the distances of crawling and gliding for the AA virus were shorter than those of the Taylor virus. Our findings indicate that like IAV, ICV also has a motility that is driven by the receptor exchange mechanism. However, compared with IAV movement, filamentous ICV movement is highly regulated in both direction and speed. Control of ICV movement is based on its specific motility employing short crawling and gliding motions as well as its own filamentous morphology. IMPORTANCE Influenza virus enters into a host cell for infection via cellular endocytosis. Human influenza virus infects epithelial cells of the respiratory tract, the surfaces of which are hidden by abundant cilia that are inactive in endocytosis. An open question is the manner by which the virus migrates to endocytosis-active domains. In analyzing individual virus behaviors through single-virus tracking, we identified a novel function of the hemagglutinin and esterase of influenza C virus (ICV) as the motility machinery. Hemagglutinin iteratively exchanges a viral receptor, causing virus movement. Esterase degrades the receptors along the trajectory traveled by the virus and prevents the virus from moving backward, causing directional movement. We propose that ICV has a unique motile machinery directionally controlled via hemagglutinin sensing the receptor density manipulated by esterase. Copyright © 2018 Sakai et al.

Treatment with insulin uncovers the motogenic capacity of nitric oxide in aortic smooth muscle cells: dependence on Gab1 and Gab1-SHP2 association.

PubMed

Dixit, Madhulika; Zhuang, Daming; Ceacareanu, Bogdan; Hassid, Aviv

2003-11-14

Contrary to the antimotogenic effect of NO in dedifferentiated vascular smooth muscle cells (VSMCs), we have reported that NO stimulates the motility of differentiated cultured VSMC isolated from adult rats. This process involves upregulation of protein tyrosine phosphatase SHP2, followed by downregulation of RhoA activity. In the present study, we tested the hypothesis that insulin alters the motogenic phenotype of cultured rat aortic smooth muscle cells exposed to NO from inhibition to stimulation of cell motility. We demonstrate for the first time that NO stimulates the motility of VSMCs cultured for several days in the presence but not the absence of insulin. Moreover, we show that NO blocks PDGF-induced cell motility in insulin-naive but not in insulin-treated cells. We also demonstrate that the scaffold adapter protein Gab1, considered a physiological activator of protein tyrosine phosphatase SHP2, increases cell motility in the presence but not the absence of insulin. In cells cultured in the presence of insulin, overexpression of Gab1 mimics, whereas a dominant-negative allele of Gab1 (Gab1YF) blocks, the motility-stimulatory effect of NO. Cotransfection experiments with dominant-negative Gab1 and wild-type SHP2 or wild-type Gab1 and dominant-negative SHP2 indicate that the two proteins work together as a functional unit to induce motility. Because chronic insulin can increase the levels of phosphatidylinositol 3 (PI3) kinase in several models of hyperinsulinemia, we also tested the potential involvement of this enzyme in mechanisms leading to increased cell motility. We found that the motogenic effect of NO, Gab1, and SHP2 was blocked by the selective PI3 kinase inhibitor LY294002, suggesting a requirement of PI3 kinase in mediating motogenesis. These observations may be relevant to molecular mechanisms related to the pathogenesis of vascular disease in hyperinsulinemic diabetes. The full text of this article is available online at http://www.circresaha.org.

Composition and metabolism of carbohydrates and lipids in Sparus aurata semen and its relation to viability expressed as sperm motility when activated.

PubMed

Lahnsteiner, Franz; Mansour, Nabil; Caberlotto, Stefano

2010-09-01

The present study investigated aspects of lipid and carbohydrate metabolism in Sparus aurata semen and tested the effect of lipids, carbohydrates and related metabolites on sperm viability using in vitro incubation experiments. Sparus aurata semen contained enzyme systems to metabolize sugars and lipids. Also key enzymes of the tricarboxylic acid cycle and enzymes involved in ATP metabolism were detected. When spermatozoa were incubated in sperm motility inhibiting saline solution for 48 h phospholipid levels decreased constantly and triglycerides levels during the first 24 h of incubation indicating that spermatozoa utilize lipids as energy resources. After 24 h triglycerides levels started to re-increase indicating a change in sperm metabolism, in particular the onset of triglycerides synthesis by the fatty acid synthase complex. In the incubation period from 0 to 24 h glucose levels were constant, and decreased thereafter. Glycogen levels did not change at all. Semen contained also considerable amounts of sialic acid, glucuronic acid and hexosamines, components of mucopolysaccharides. To find out whether lipids, carbohydrates, and related metabolites had a positive effect on sperm functionality semen was incubated together with the described compounds in sperm motility inhibiting saline solution and motility when activated was determined. In the control 37.2+/-10.1% of the spermatozoa were locally motile and 38.3+/-13.3% motile after 24 h, 36.4+/-5.2% were locally motile and 9.6+/-4.5% were motile after 48 h. The swimming velocity was 89.0+/-13.1 microm/s after 24 h and 61.3+/-12.6% after 48 h. Different types of lipids (arachidic acid, linoleic acid, and glycerol trimyristate) and metabolites acting as fuel for the tricarboxylic acid cycle (hydroxybutyrate, ketoglutarate, and pyruvate) had a positive effect on the sperm viability. Tested carbohydrates (fucose, galactose, glucosamine, glucose, glucoheptose, glycogen, and sialic acid) had no effect. Also lactate and fructose-6-phosphate had no effect on sperm viability while glucose-6-phosphate, oxalacetate, and phosphoglycerate had negative effects. 2010 Elsevier Inc. All rights reserved.

Post-thaw amendment of cryopreserved sperm for use in artificial insemination of a viviparous fish, the green swordtail Xiphophorus helleri

PubMed Central

Dong, Qiaoxiang; Huang, Changjiang; Tiersch, Terrence R.

2017-01-01

Sperm cryopreservation protocols have been developed for live-bearers such as the green swordtail Xiphophorus helleri and the platyfish Xiphophorus couchianus. Despite the high post-thaw motility (~75%) obtained in both species, the requirements of sperm storage within the female reproductive tract coupled with the process of internal fertilization place functional demands upon cryopreserved sperm samples far beyond those of oviparous species. The purpose of this study was to facilitate the artificial insemination process with cryopreserved sperm of X. helleri through evaluation of parameters related to sperm quality after thawing. Specifically, this study evaluated the effects on motility for fresh and thawed sperm samples of centrifugation (for concentration of sperm and washing for removal of cryoprotectant), ionic composition, and additions of glucose and fetal bovine serum (FBS) in extender solutions. Centrifugation at 1000 ×g for 10 min at 4 °C was found to have no adverse effects on sperm motility of fresh samples, and for cryopreserved samples, the removal of glycerol by washing yielded higher and longer post-thaw motility (e.g., 168 h vs. 48 h for the controls). Suspension of fresh sperm samples in magnesium-free Hanks’ balanced salt solution (HBSS) did not affect motility; however, HBSS prepared with the absence of potassium or calcium, and the use of unsupplemented saline (NaCl alone) as extenders significantly reduced sperm motility. The presence of glucose in HBSS yielded higher and longer motility for fresh and thawed samples, but addition of glucose at greater than 2 g/L were unnecessary. Addition of 20% FBS prior to freezing was found to increase the post-thaw motility significantly compared to control treatment with 14% glycerol alone. Also addition of 20% FBS after thawing and centrifugation was found to induce the formation of sperm bundles, which may be beneficial for internal fertilization success. In conclusion, concentration of sperm and the removal of cryoprotectant (through centrifugation), and the addition of 20% FBS in the extender is recommended for future insemination trials with cryopreserved samples. PMID:29269962

[Esophageal motility characteristics of refractory heartburn: a study based on high resolution manometry and 24 hour pH-impedance monitoring].

PubMed

Wang, Kun; Duan, Liping; Xia, Zhiwei; Xu, Zhijie; Ge, Ying

2014-09-16

To analyze the esophageal motility characteristics of refractory heartburn with different reflux patterns and preliminarily clarify the roles of esophageal disorder in refractory heartburn. A total of 176 refractory heartburn patients were enrolled from 2009 to 2013. After gastroscopy and 24 hour pH-impedance monitoring, they were divided into 4 groups of reflux esophagitis (RE, n = 29), non-erosive reflux disease with acid reflux (NERD-acid, n = 51), NERD with weakly acidic reflux (NERD-weakly acid, n = 51) and non-reflux associated heartburn (n = 45). All subjects undertake high resolution manometry test and their esophageal motility functions were analyzed by the Chicago classification criteria 2012. Among them, 60.23% (106/176) patients presented esophageal motility disorders. And 42.61% (75/176) fulfilled the criteria of weak peristalsis, 7.39% (13/176) distal esophageal spasm, 4.55% (8/176) rapid contraction, 3.98% (7/176) EGJ outflow obstruction, 1.14% (2/176) hiatus hernia and 1 Jackhammer esophagus. The detection rates of esophageal motility disorder were similar among 4 groups and weak peristalsis was the most common disorder in all groups (41.38% in RE, 37.25% in NERD-acid patients, 54.90% in NERD-weakly acid and 35.56% in non-reflux associated heartburn patients). However, hypertensive motility disorders in non-reflux associated heartburn group (31.11%, 14/45) were more than GERD subgroups (11.45%, 15/131) (P < 0.05) . The relax ratio of low esophagus sphincter (LES) in GERD subgroups were higher than that in non-reflux associated heartburn patients. And the relax ratio of NERD-weakly acid was significantly higher than that in non-reflux associated heartburn patients (65% (50%-80%) vs 58% (42%-67%) , P < 0.05). The integrated relaxation pressure in GERD subgroups were lower than that of non-reflux associated heartburn patients without significant differences (P > 0.05). Esophageal weak peristalsis is one of the most common motility disorders in refractory heartburn patients, and esophageal hypertensive motility disorders are common in non-reflux associated heartburn patients. Esophageal manometry is necessary for the diagnosis and treatment of refractory heartburn.

Plasticity of vagal brainstem circuits in the control of gastric function

PubMed Central

Browning, Kirsteen N.; Travagli, R. Alberto

2010-01-01

Background Sensory information from the viscera, including the gastrointestinal (GI) tract, is transmitted through the afferent vagus via a glutamatergic synapse to neurons of the nucleus tractus solitarius (NTS), which integrate this sensory information to regulate autonomic functions and homeostasis. The integrated response is conveyed to, amongst other nuclei, the preganglionic neurons of the dorsal motor nucleus of the vagus (DMV) using mainly GABA, glutamate and catecholamines as neurotransmitters. Despite being modulated by almost all the neurotransmitters tested so far, the glutamatergic synapse between NTS and DMV does not appear to be tonically active in the control of gastric motility and tone. Conversely, tonic inhibitory GABAergic neurotransmission from the NTS to the DMV appears critical in setting gastric tone and motility, yet, under basal conditions, this synapse appears resistant to modulation. Purpose Here, we review the available evidence suggesting that vagal efferent output to the GI tract is regulated, perhaps even controlled, in an “on-demand” and efficient manner in response to ever-changing homeostatic conditions. The focus of this review is on the plasticity induced by variations in the levels of second messengers in the brainstem neurons that form vago-vagal reflex circuits. Emphasis is placed upon the modulation of GABAergic transmission to DMV neurons and the modulation of afferent input from the GI tract by neurohormones/neurotransmitters and macronutrients. Derangement of this “on-demand” organization of brainstem vagal circuits may be one of the factors underlying the pathophysiological changes observed in functional dyspepsia or hyperglycemic gastroparesis. PMID:20804520

The Significance of Interstitial Cells in Neurogastroenterology

PubMed Central

Blair, Peter J; Rhee, Poong-Lyul; Sanders, Kenton M; Ward, Sean M

2014-01-01

Smooth muscle layers of the gastrointestinal tract consist of a heterogeneous population of cells that include enteric neurons, several classes of interstitial cells of mesenchymal origin, a variety of immune cells and smooth muscle cells (SMCs). Over the last number of years the complexity of the interactions between these cell types has begun to emerge. For example, interstitial cells, consisting of both interstitial cells of Cajal (ICC) and platelet-derived growth factor receptor alpha-positive (PDGFRα+) cells generate pacemaker activity throughout the gastrointestinal (GI) tract and also transduce enteric motor nerve signals and mechanosensitivity to adjacent SMCs. ICC and PDGFRα+ cells are electrically coupled to SMCs possibly via gap junctions forming a multicellular functional syncytium termed the SIP syncytium. Cells that make up the SIP syncytium are highly specialized containing unique receptors, ion channels and intracellular signaling pathways that regulate the excitability of GI muscles. The unique role of these cells in coordinating GI motility is evident by the altered motility patterns in animal models where interstitial cell networks are disrupted. Although considerable advances have been made in recent years on our understanding of the roles of these cells within the SIP syncytium, the full physiological functions of these cells and the consequences of their disruption in GI muscles have not been clearly defined. This review gives a synopsis of the history of interstitial cell discovery and highlights recent advances in structural, molecular expression and functional roles of these cells in the GI tract. PMID:24948131

Functional Architecture of the Outer Arm Dynein Conformational Switch*

PubMed Central

King, Stephen M.; Patel-King, Ramila S.

2012-01-01

Dynein light chain 1 (LC1/DNAL1) is one of the most highly conserved components of ciliary axonemal outer arm dyneins, and it associates with both a heavy chain motor unit and tubulin located within the A-tubule of the axonemal outer doublet microtubules. In a variety of model systems, lack of LC1 or expression of mutant forms leads to profound defects in ciliary motility, including the failure of the hydrodynamic coupling needed for ciliary metachronal synchrony, random stalling during the power/recovery stroke transition, an aberrant response to imposed viscous load, and in some cases partial failure of motor assembly. These phenotypes have led to the proposal that LC1 acts as part of a mechanical switch to control motor function in response to alterations in axonemal curvature. Here we have used NMR chemical shift mapping to define the regions perturbed by a series of mutations in the C-terminal domain that yield a range of phenotypic effects on motility. In addition, we have identified the subdomain of LC1 involved in binding microtubules and characterized the consequences of an Asn → Ser alteration within the terminal leucine-rich repeat that in humans causes primary ciliary dyskinesia. Together, these data define a series of functional subdomains within LC1 and allow us to propose a structural model for the organization of the dynein heavy chain-LC1-microtubule ternary complex that is required for the coordinated activity of dynein motors in cilia. PMID:22157010

Influence of porcine spermadhesins on the susceptibility of boar spermatozoa to high dilution.

PubMed

Centurion, Fernando; Vazquez, Juan M; Calvete, Juan J; Roca, Jordi; Sanz, Libia; Parrilla, Inmaculada; Garcia, Eva M; Martinez, Emilio A

2003-08-01

The effect of heparin-binding and non-heparin-binding spermadhesins on the viability, motility, and mitochondrial activity of boar spermatozoa at the high dilution (300,000 sperm/ml) to which sperm are exposed during the process of sex sorting by flow cytometry was investigated. Incubation of spermatozoa with heparin-binding spermadhesins caused a time- and dose-dependent decrease in the percentage of functional spermatozoa. The percentage of viable spermatozoa incubated at 38 degrees C with heparin-binding spermadhesins diluted in PBS (1 mg/ml) dropped from 75% (0.5 h) to 4% (5 h), whereas the percentage of viable spermatozoa incubated in PBS without proteins (control) decreased from 85% (0.5 h) to 19% (5 h). Addition of non-heparin-binding PSP-I/PSP-II spermadhesin to the PBS resulted in a concentration-dependent increment of the percentage of viable cells (65% after 5-h incubation), with maximum effect at 1.5 mg/ml. The heparin-binding spermadhesins totally suppressed sperm motility and mitochondrial activity after 5 h of incubation. The same parameters of sperm incubated in the presence of 1.5 mg/ml of PSP-I/PSP-II were 50% and 58%, respectively, and the percentages of control sperm displaying motility and mitochondrial activity were 21% and 26%, respectively. Moreover, the viability, motility, and mitochondrial activity all decreased on incubation of spermatozoa with mixtures of PSP-I/PSP-II and heparin-binding spermadhesins as the concentration of the latter increased. We conclude that PSP-I/PSP-II and the heparin-binding spermadhesins exert antagonistic effects on the functionality of highly diluted boar spermatozoa. The finding that PSP-I/PSP-II contributes to maintaining sperm with high viability, motility, and mitochondrial activity for at least 5 h at physiological temperature points to its potential use as an additive for sperm preservation, specifically of highly diluted, flow-sorted spermatozoa for sex preselection.

A prefoldin-associated WD-repeat protein (WDR92) is required for the correct architectural assembly of motile cilia

PubMed Central

Patel-King, Ramila S.; King, Stephen M.

2016-01-01

WDR92 is a highly conserved WD-repeat protein that has been proposed to be involved in apoptosis and also to be part of a prefoldin-like cochaperone complex. We found that WDR92 has a phylogenetic signature that is generally compatible with it playing a role in the assembly or function of specifically motile cilia. To test this hypothesis, we performed an RNAi-based knockdown of WDR92 gene expression in the planarian Schmidtea mediterranea and were able to achieve a robust reduction in mRNA expression to levels undetectable under our standard RT-PCR conditions. We found that this treatment resulted in a dramatic reduction in the rate of organismal movement that was caused by a switch in the mode of locomotion from smooth, cilia-driven gliding to muscle-based, peristaltic contractions. Although the knockdown animals still assembled cilia of normal length and in similar numbers to controls, these structures had reduced beat frequency and did not maintain hydrodynamic coupling. By transmission electron microscopy we observed that many cilia had pleiomorphic defects in their architecture, including partial loss of dynein arms, incomplete closure of the B-tubule, and occlusion or replacement of the central pair complex by accumulated electron-dense material. These observations suggest that WDR92 is part of a previously unrecognized cytoplasmic chaperone system that is specifically required to fold key components necessary to build motile ciliary axonemes. PMID:26912790

Modulatory effect of intestinal polyamines and trace amines on the spontaneous phasic contractions of the isolated ileum and colon rings of mice

PubMed Central

Sánchez, Manuel; Suárez, Lorena; Andrés, María Teresa; Flórez, Blanca Henar; Bordallo, Javier; Riestra, Sabino; Cantabrana, Begoña

2017-01-01

ABSTRACT Background: Gastrointestinal motility modulatory factors include substances of the intestinal content, such as polyamines and trace amines (TAs), the focus of this study. Methods: The amines of food, intestinal content and from faecal bacteria of Swiss mice were determined by HPLC and functionally characterised in isolated distal ileum and medial colon rings. Results: Mouse food and intestinal content contain polyamines (spermidine>putrescine>spermine) and TAs (isoamylamine>cadaverine). Intestinal bacteria mainly produce putrescine and cadaverine. The amines inhibited the spontaneous motility of the ileum (0.1-3 mM) and colon rings (0.01-3 mM, with lower IC50), with: spermine~isoamylamine~spermidine. Spermine inhibition was tetrodotoxin (TTX)-insensitive, while isoamylamine was TTX-sensitive, suggesting neural control. Mainly in the ileum, isoamylamine (3 mM) elicited acute effects modified by TTX, atropine and propranolol, and suppressed by spermine (3 mM), not being localized at the smooth muscle level. The amines assayed (3 mM), except putrescine and cadaverine in the ileum and isoamylamine in the colon, antagonised acetylcholine (ACh, 0.1 mM)-elicited phasic contractions. Isoamylamine and spermine in colon relaxed KCl (100 mM)-elicited tonic contractions, suggesting an effect on smooth muscle, but did not justify the suppression of motility caused by spermine and isoamylamine. Conclusions: Polyamines and TAs of the intestinal content might act on chemosensors and modulate intestinal peristalsis. PMID:28659731

Etiology and functional validation of gastrointestinal motility dysfunction in a zebrafish model of CHARGE syndrome.

PubMed

Cloney, Kellie; Steele, Shelby L; Stoyek, Matthew R; Croll, Roger P; Smith, Frank M; Prykhozhij, Sergey V; Brown, Mary M; Midgen, Craig; Blake, Kim; Berman, Jason N

2018-06-01

CHARGE syndrome is linked to autosomal-dominant mutations in the CHD7 gene and results in a number of physiological and structural abnormalities, including heart defects, hearing and vision loss, and gastrointestinal (GI) problems. Of these challenges, GI problems have a profound impact throughout an individual's life, resulting in increased morbidity and mortality. A homolog of CHD7 has been identified in the zebrafish, the loss of which recapitulates many of the features of the human disease. Using a morpholino chd7 knockdown model complemented by a chd7 null mutant zebrafish line, we examined GI structure, innervation, and motility in larval zebrafish. Loss of chd7 resulted in physically smaller GI tracts with normal epithelial and muscular histology, but decreased and disorganized vagal projections, particularly in the foregut. chd7 morphant larvae had significantly less ability to empty their GI tract of gavaged fluorescent beads, and this condition was only minimally improved by the prokinetic agents, domperidone and erythromycin, in keeping with mixed responses to these agents in patients with CHARGE syndrome. The conserved genetics and transparency of the zebrafish have provided new insights into the consequences of chd7 gene dysfunction on the GI system and cranial nerve patterning. These findings highlight the opportunity of the zebrafish to serve as a preclinical model for studying compounds that may improve GI motility in individuals with CHARGE syndrome. © 2018 Federation of European Biochemical Societies.

Effect of semen collection method on sperm motility of gray wolves (Canis lupus) and domestic dogs (C. l. familiaris).

PubMed

Christensen, Bruce W; Asa, Cheryl S; Wang, Chong; Vansandt, Lindsey; Bauman, Karen; Callahan, Margaret; Jens, Jackie K; Ellinwood, N Matthew

2011-09-15

Genetic management of Mexican gray wolves includes semen banking, but due to the small number of animals in the population and handling restrictions, improvements in semen collection and cryopreservation rely on results from studies of domestic dogs. Semen collection from wolves requires anesthesia and electroejaculation, which introduce potentially important variables into species comparisons, as dog semen is typically collected manually from conscious animals. To investigate possible effects of collection method on semen quality, we compared semen collection by the traditional manual method and by electroejaculation (EE) in a group of dogs (n = 5) to collection by EE only in wolves (n = 7). Samples were divided into two aliquots: neat or diluted in Tris/egg yolk extender, with motility evaluated at intervals up to 24 h. There were no differences (P > 0.10) in sperm motility in either neat or extended samples at 24 h from EE dogs and wolves, although motility of the wolf neat samples declined more rapidly (P < 0.05). However, there were differences (P < 0.01) between EE and manually collected dog semen in motility at 24 h, in both the neat and extended samples. Therefore, general motility patterns of dog and wolf semen collected by EE were similar, especially when diluted with a Tris/egg yolk extender, but sperm collected from dogs by EE did not maintain motility as long as manually collected samples, perhaps related to the longer exposure of EE samples to more prostate fluid. Copyright © 2011 Elsevier Inc. All rights reserved.

From ischochymia to gastroparesis: proposed mechanisms and preferred management of dyspepsia over the centuries.

PubMed

Bielefeldt, Klaus

2014-06-01

Dyspeptic symptoms are common with most patients suffering functional disorders that remain a therapeutic challenge for medical practitioners. Within the last three decades, gastric infection, altered motility, and hypersensitivity have gained and lost traction in explaining the development of functional dyspepsia. Considering these shifts, the aim of this review was to analyze changing understanding of and approaches to dyspepsia over a longer time period. Monographs, textbooks, and articles published during the last three centuries show that our understanding of normal gastric function has improved dramatically. With increased insight came new ideas about disease mechanisms, diagnostic options, and treatments. Despite shifts over time, the importance of functional abnormalities was recognized early on and explained in the context of societal influences and stressors, anxieties, and biological influences, thus resembling the contemporary biopsychosocial model of illness. Symptoms were often attributed to changes in secretion, motility, and sensation or perception with technological innovation often influencing proposed mechanisms and treatments. Many of the principles or even agents applied more than a century ago are still part of today's approach. This includes acid suppression, antiemetics, analgesics, and even non-pharmacologic therapies, such as gastric decompression or electrical stimulation of the stomach. This historical information does not only help us understand how we arrived at our current state of knowledge and standards of care, it also demonstrates that enthusiastic adoption of various competing explanatory models and the resulting treatments often did not survive the test of time. In view of the benign prognosis of dyspepsia, the data may function as a call for caution to avoid the potential harm of overly aggressive approaches or treatments with a high likelihood of adverse effects.

The Nervous System and Gastrointestinal Function

ERIC Educational Resources Information Center

Altaf, Muhammad A.; Sood, Manu R.

2008-01-01

The enteric nervous system is an integrative brain with collection of neurons in the gastrointestinal tract which is capable of functioning independently of the central nervous system (CNS). The enteric nervous system modulates motility, secretions, microcirculation, immune and inflammatory responses of the gastrointestinal tract. Dysphagia,…

Reptin/Ruvbl2 is a Lrrc6/Seahorse interactor essential for cilia motility

PubMed Central

Zhao, Lu; Yuan, Shiaulou; Cao, Ying; Kallakuri, Sowjanya; Li, Yuanyuan; Kishimoto, Norihito; DiBella, Linda; Sun, Zhaoxia

2013-01-01

Primary ciliary dyskinesia (PCD) is an autosomal recessive disease caused by defective cilia motility. The identified PCD genes account for about half of PCD incidences and the underlying mechanisms remain poorly understood. We demonstrate that Reptin/Ruvbl2, a protein known to be involved in epigenetic and transcriptional regulation, is essential for cilia motility in zebrafish. We further show that Reptin directly interacts with the PCD protein Lrrc6/Seahorse and this interaction is critical for the in vivo function of Lrrc6/Seahorse in zebrafish. Moreover, whereas the expression levels of multiple dynein arm components remain unchanged or become elevated, the density of axonemal dynein arms is reduced in reptinhi2394 mutants. Furthermore, Reptin is highly enriched in the cytosol and colocalizes with Lrrc6/Seahorse. Combined, these results suggest that the Reptin-Lrrc6/Seahorse complex is involved in dynein arm formation. We also show that although the DNA damage response is induced in reptinhi2394 mutants, it remains unchanged in cilia biogenesis mutants and lrrc6/seahorse mutants, suggesting that increased DNA damage response is not intrinsic to ciliary defects and that in vertebrate development, Reptin functions in multiple processes, both cilia specific and cilia independent. PMID:23858445

Reptin/Ruvbl2 is a Lrrc6/Seahorse interactor essential for cilia motility.

PubMed

Zhao, Lu; Yuan, Shiaulou; Cao, Ying; Kallakuri, Sowjanya; Li, Yuanyuan; Kishimoto, Norihito; DiBella, Linda; Sun, Zhaoxia

2013-07-30

Primary ciliary dyskinesia (PCD) is an autosomal recessive disease caused by defective cilia motility. The identified PCD genes account for about half of PCD incidences and the underlying mechanisms remain poorly understood. We demonstrate that Reptin/Ruvbl2, a protein known to be involved in epigenetic and transcriptional regulation, is essential for cilia motility in zebrafish. We further show that Reptin directly interacts with the PCD protein Lrrc6/Seahorse and this interaction is critical for the in vivo function of Lrrc6/Seahorse in zebrafish. Moreover, whereas the expression levels of multiple dynein arm components remain unchanged or become elevated, the density of axonemal dynein arms is reduced in reptin(hi2394) mutants. Furthermore, Reptin is highly enriched in the cytosol and colocalizes with Lrrc6/Seahorse. Combined, these results suggest that the Reptin-Lrrc6/Seahorse complex is involved in dynein arm formation. We also show that although the DNA damage response is induced in reptin(hi2394) mutants, it remains unchanged in cilia biogenesis mutants and lrrc6/seahorse mutants, suggesting that increased DNA damage response is not intrinsic to ciliary defects and that in vertebrate development, Reptin functions in multiple processes, both cilia specific and cilia independent.

Emerging ciliopathies: are respiratory cilia compromised in Usher syndrome?

PubMed

Piatti, G; De Santi, M M; Brogi, M; Castorina, P; Ambrosetti, U

2014-01-01

Usher syndrome is a ciliopathy involving photoreceptors and cochlear hair cells (sensory cilia): since sensory and motor ciliopathies can overlap, we analysed the respiratory cilia (motile) in 17 patients affected by Usher syndrome and 18 healthy control subject. We studied the mucociliary transport time with the saccharine test, ciliary motility and ultrastructure of respiratory cilia obtained by nasal brushing; we also recorded the classical respiratory function values by spirometry. All enrolled subjects showed normal respiratory function values. The mean mucociliary transport time with saccharine was 22.33 ± 17.96 min, which is in the range of normal values. The mean ciliary beat frequency of all subjects was 8.81 ± 2.18 Hz, which is a value approaching the lower physiological limit. None of the classical ciliary alterations characterizing the "ciliary primary dyskinesia" was detected, although two patients showed alterations in number and arrangement of peripheral microtubules and one patient had abnormal ciliary roots. Respiratory cilia in Usher patients don't seem to have evident ultrastructural alterations, as expected, but the fact that the ciliary motility appeared slightly reduced could emphasize that a rigid distinction between sensory and motor ciliopathies may not reflect what really occurs. Copyright © 2014 Elsevier Inc. All rights reserved.

Different concentrations of cysteamine and ergothioneine improve microscopic and oxidative parameters in ram semen frozen with a soybean lecithin extender.

PubMed

Najafi, Abozar; Kia, Hossein Daghigh; Mohammadi, Hossein; Najafi, Mir Hossein; Zanganeh, Zaynab; Sharafi, Mohsen; Martinez-Pastor, Felipe; Adeldust, Hamideh

2014-08-01

The aim of this study was to evaluate the effects of ergothioneine and cysteamine as antioxidant supplements in a soybean lecithin extender for freezing ram semen. Twenty-four ejaculates were collected from four rams and diluted with extenders (1.5% soybean lecithin, 7% glycerol) containing no supplements (control) and cysteamine or ergothioneine (2, 4, 6 or 8mM). Motility by CASA, viability, plasma membrane functionality (HOS test), total abnormality, lipid peroxidation, glutathione peroxidase (GPx) activity and capacitation status (CTC staining) were assessed after thawing. Using 6mM of either antioxidant improved total motility. Cysteamine at 6mM and ergothioneine at 4 and 6mM improved viability and reduced lipid peroxidation (malondialdehyde concentration). Both antioxidants improved membrane functionality significantly, except at 8mM. Progressive motility, kinematic parameters, GPx activity, capacitation status and sperm abnormalities were not influenced by the antioxidant supplements. In conclusion, cysteamine at 6mM and ergothioneine at 4 or 6mM seem to improve the post-thawing quality of ram semen cryopreserved in a soybean lecithin extender. Copyright © 2014 Elsevier Inc. All rights reserved.

Flagellated bacterial motility in polymer solutions

PubMed Central

Martinez, Vincent A.; Schwarz-Linek, Jana; Reufer, Mathias; Wilson, Laurence G.; Morozov, Alexander N.; Poon, Wilson C. K.

2014-01-01

It is widely believed that the swimming speed, v, of many flagellated bacteria is a nonmonotonic function of the concentration, c, of high-molecular-weight linear polymers in aqueous solution, showing peaked v(c) curves. Pores in the polymer solution were suggested as the explanation. Quantifying this picture led to a theory that predicted peaked v(c) curves. Using high-throughput methods for characterizing motility, we measured v and the angular frequency of cell body rotation, Ω, of motile Escherichia coli as a function of polymer concentration in polyvinylpyrrolidone (PVP) and Ficoll solutions of different molecular weights. We find that nonmonotonic v(c) curves are typically due to low-molecular-weight impurities. After purification by dialysis, the measured v(c) and Ω(c) relations for all but the highest-molecular-weight PVP can be described in detail by Newtonian hydrodynamics. There is clear evidence for non-Newtonian effects in the highest-molecular-weight PVP solution. Calculations suggest that this is due to the fast-rotating flagella seeing a lower viscosity than the cell body, so that flagella can be seen as nano-rheometers for probing the non-Newtonian behavior of high polymer solutions on a molecular scale. PMID:25468981

H{sup +} and Na{sup +} are involved in flagellar rotation of the spirochete Leptospira

DOE Office of Scientific and Technical Information (OSTI.GOV)

Islam, Md. Shafiqul; Morimoto, Yusuke V.; Graduate School of Frontier BioSciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871

2015-10-16

Leptospira is a spirochete possessing intracellular flagella. Each Leptospira flagellar filament is linked with a flagellar motor composed of a rotor and a dozen stators. For many bacterial species, it is known that the stator functions as an ion channel and that the ion flux through the stator is coupled with flagellar rotation. The coupling ion varies depending on the species; for example, H{sup +} is used in Escherichia coli, and Na{sup +} is used in Vibrio spp. to drive a polar flagellum. Although genetic and structural studies illustrated that the Leptospira flagellar motor also contains a stator, the couplingmore » ion for flagellar rotation remains unknown. In the present study, we analyzed the motility of Leptospira under various pH values and salt concentrations. Leptospira cells displayed motility in acidic to alkaline pH. In the presence of a protonophore, the cells completely lost motility in acidic to neutral pH but displayed extremely slow movement under alkaline conditions. This result suggests that H{sup +} is a major coupling ion for flagellar rotation over a wide pH range; however, we also observed that the motility of Leptospira was significantly enhanced by the addition of Na{sup +}, though it vigorously moved even under Na{sup +}-free conditions. These results suggest that H{sup +} is preferentially used and that Na{sup +} is secondarily involved in flagellar rotation in Leptospira. The flexible ion selectivity in the flagellar system could be advantageous for Leptospira to survive in a wide range of environment. - Highlights: • This is a study on input energy for motility in the spirochete Leptospira. • Leptospira biflexa exhibited active motility in acidic to alkaline pH. • Both H{sup +} and Na{sup +} are involved in flagellar rotation in Leptospira. • H{sup +} is a primary energy source, but Na{sup +} can secondarily enhance motility.« less

[Thyroid-intestinal motility interactions summary].

PubMed

Pustorino, S; Foti, M; Calipari, G; Pustorino, E; Ferraro, R; Guerrisi, O; Germanotta, G

2004-12-01

Thyroid diseases may be related to gastrointestinal motility symptoms. Such symptoms can vary in degree and, sometimes, are the only clue of a thyroid disease or, at least, the first. The mechanism by which the thyroid hormones can influence gastrointestinal motility, even if not still completely elucidated, can be found in a synergism between a direct effect of the thyronins and an indirect effect mediated by cathecolamines on the muscle cell receptors. Neck discomfort and dysphagia are common findings in patients with thyroid diseases. Hyper- and hypothyroidism can impair esophageal motility, modifying pharyngo-esophageal structure and/or muscular function and interacting with the neuro-humoral regulation of the esophageal peristalsis. Oesophageal motility alterations, observed in patients affected by small non-toxic goiter, are less understandable. At the gastro-duodenal level, basic and postprandial electric rhythm alterations have been observed in hyperthyroid patients, often associated with delayed gastric emptying, too. In such patients, the autonomous nervous system dysfunction may even modify the neuro-hormonal mutual regulation (vagal influence decrease) of the gastro-duodenal myoelectric activity. Hypothyroidism may cause a delay of the gastric emptying too, but such pattern may also be related to an associated autoimmune disease or to an independent chronic modification of the gastric mucosa. Diarrhoea and malabsorption are common findings together with hyperthyroidism, whereas constipation is frequently observed in hypothyroidism. The clinically most demanding situation is certainly the secondary chronic intestinal pseudo-obstruction syndrome, which involves the bowel in most cases, but may also show up by means of a mega-small bowel or a mega-duodenum, or even all of the above. In conclusion it may be stated that: 1) thyroid diseases may be related to symptoms due to digestive motility dysfunction. 2) Any segment of the gastrointestinal trait may be involved. 3) The typical clinical manifestations of the thyroid illnesses may be borderline, missing or concealed by other intercurrent illnesses, especially in the elderly patients. 4) Motility-related digestive symptoms may conceal an underlying, easily misdetected, thyroid disease and must be therefore carefully analyzed.

Comparison of protocols for cryopreservation of rhesus monkey spermatozoa by post-thaw motility recovery and hyperactivation.

PubMed

Nichols, S M; Bavister, B D

2006-01-01

Cryopreservation of spermatozoa is useful for gene banking and for in vitro fertilisation (IVF). This study compared several published cryopreservation techniques to find the most efficient for rhesus macaques. Effectiveness was assessed by sperm longevity (post-thaw motility % and duration) and ability to hyperactivate in response to chemical activators (caffeine, dibutyryl cyclic AMP). Each ejaculate from three males was treated with four published cryopreservation protocols (Seier et al. 1993; Sanchez-Partida et al. 2000; Si et al. 2000; Isachenko et al. 2005). Upon thawing, each sub-sample was incubated either at 37 degrees C in 5% CO2 in air with or without activators or at approximately 22 degrees C in atmospheric air without activators for 0-24 h. Samples cryopreserved using one method showed zero motility and were not included in the 2 ;2 G-test statistical analysis. The other methods all demonstrated good immediate post-thaw motility rates (68%, 73% and 62% respectively) and underwent capacitation after exposure to activators. Sperm motility in each treatment decreased over time at both temperatures but overall, incubation at 22 degrees C preserved motility better in all three methods. In summary, cryopreservation of rhesus spermatozoa using the method published by Sanchez-Partida et al. or Seier et al. appeared best, potentially supporting gene banking as well as allowing for multiple IVF uses from the same sample.

Function of MYO7A in the Human RPE and the Validity of Shaker1 Mice as a Model for Usher Syndrome 1B

PubMed Central

Gibbs, Daniel; Diemer, Tanja; Khanobdee, Kornnika; Hu, Jane; Bok, Dean

2010-01-01

Purpose. To investigate the function of MYO7A in human RPE cells and to test the validity of using shaker1 RPE in preclinical studies on therapies for Usher syndrome 1B by comparing human and mouse cells. Methods. MYO7A was localized by immunofluorescence. Primary cultures of human and mouse RPE cells were used to measure melanosome motility and rod outer segment (ROS) phagocytosis and digestion. MYO7A was knocked down in the human RPE cells by RNAi to test for a mutant phenotype in melanosome motility. Results. The distribution of MYO7A in the RPE of human and mouse was found to be comparable, both in vivo and in primary cultures. Primary cultures of human RPE cells phagocytosed and digested ROSs with kinetics comparable to that of primary cultures of mouse RPE cells. Melanosome motility was also comparable, and, after RNAi knockdown, consisted of longer-range fast movements characteristic of melanosomes in shaker1 RPE. Conclusions. The localization and function of MYO7A in human RPE cells is comparable to that in mouse RPE cells. Although shaker1 retinas do not undergo degeneration, correction of mutant phenotypes in the shaker1 RPE represents a valid preclinical test for potential therapeutic treatments. PMID:19643958

Insights into the Structure and Function of Ciliary and Flagellar Doublet Microtubules

PubMed Central

Linck, Richard; Fu, Xiaofeng; Lin, Jianfeng; Ouch, Christna; Schefter, Alexandra; Steffen, Walter; Warren, Peter; Nicastro, Daniela

2014-01-01

Cilia and flagella are conserved, motile, and sensory cell organelles involved in signal transduction and human disease. Their scaffold consists of a 9-fold array of remarkably stable doublet microtubules (DMTs), along which motor proteins transmit force for ciliary motility and intraflagellar transport. DMTs possess Ribbons of three to four hyper-stable protofilaments whose location, organization, and specialized functions have been elusive. We performed a comprehensive analysis of the distribution and structural arrangements of Ribbon proteins from sea urchin sperm flagella, using quantitative immunobiochemistry, proteomics, immuno-cryo-electron microscopy, and tomography. Isolated Ribbons contain acetylated α-tubulin, β-tubulin, conserved protein Rib45, >95% of the axonemal tektins, and >95% of the calcium-binding proteins, Rib74 and Rib85.5, whose human homologues are related to the cause of juvenile myoclonic epilepsy. DMTs contain only one type of Ribbon, corresponding to protofilaments A11-12-13-1 of the A-tubule. Rib74 and Rib85.5 are associated with the Ribbon in the lumen of the A-tubule. Ribbons contain a single ∼5-nm wide filament, composed of equimolar tektins A, B, and C, which interact with the nexin-dynein regulatory complex. A summary of findings is presented, and the functions of Ribbon proteins are discussed in terms of the assembly and stability of DMTs, ciliary motility, and other microtubule systems. PMID:24794867

Choline dehydrogenase polymorphism rs12676 is a functional variation and is associated with changes in human sperm cell function.

PubMed

Johnson, Amy R; Lao, Sai; Wang, Tongwen; Galanko, Joseph A; Zeisel, Steven H

2012-01-01

Approximately 15% of couples are affected by infertility and up to half of these cases arise from male factor infertility. Unidentified genetic aberrations such as chromosomal deletions, translocations and single nucleotide polymorphisms (SNPs) may be the underlying cause of many cases of idiopathic male infertility. Deletion of the choline dehydrogenase (Chdh) gene in mice results in decreased male fertility due to diminished sperm motility; sperm from Chdh(-/-) males have decreased ATP concentrations likely stemming from abnormal sperm mitochondrial morphology and function in these cells. Several SNPs have been identified in the human CHDH gene that may result in altered CHDH enzymatic activity. rs12676 (G233T), a non-synonymous SNP located in the CHDH coding region, is associated with increased susceptibility to dietary choline deficiency and risk of breast cancer. We now report evidence that this SNP is also associated with altered sperm motility patterns and dysmorphic mitochondrial structure in sperm. Sperm produced by men who are GT or TT for rs12676 have 40% and 73% lower ATP concentrations, respectively, in their sperm. rs12676 is associated with decreased CHDH protein in sperm and hepatocytes. A second SNP located in the coding region of IL17BR, rs1025689, is linked to altered sperm motility characteristics and changes in choline metabolite concentrations in sperm.

Choline Dehydrogenase Polymorphism rs12676 Is a Functional Variation and Is Associated with Changes in Human Sperm Cell Function

PubMed Central

Johnson, Amy R.; Lao, Sai; Wang, Tongwen; Galanko, Joseph A.; Zeisel, Steven H.

2012-01-01

Approximately 15% of couples are affected by infertility and up to half of these cases arise from male factor infertility. Unidentified genetic aberrations such as chromosomal deletions, translocations and single nucleotide polymorphisms (SNPs) may be the underlying cause of many cases of idiopathic male infertility. Deletion of the choline dehydrogenase (Chdh) gene in mice results in decreased male fertility due to diminished sperm motility; sperm from Chdh−/− males have decreased ATP concentrations likely stemming from abnormal sperm mitochondrial morphology and function in these cells. Several SNPs have been identified in the human CHDH gene that may result in altered CHDH enzymatic activity. rs12676 (G233T), a non-synonymous SNP located in the CHDH coding region, is associated with increased susceptibility to dietary choline deficiency and risk of breast cancer. We now report evidence that this SNP is also associated with altered sperm motility patterns and dysmorphic mitochondrial structure in sperm. Sperm produced by men who are GT or TT for rs12676 have 40% and 73% lower ATP concentrations, respectively, in their sperm. rs12676 is associated with decreased CHDH protein in sperm and hepatocytes. A second SNP located in the coding region of IL17BR, rs1025689, is linked to altered sperm motility characteristics and changes in choline metabolite concentrations in sperm. PMID:22558321

Disorders of the Large Intestine

MedlinePlus

... Chapel Hill, NC from the Functional GI Disorder Education Guide, IFFGD; 2005, and "Characteristics of Chronic Constipation" IFFGD; 2006. (Accessed April 15, 2006) Link. Digestive ... Motility Testing Esophagus Stomach Small ...

Multimodal microfluidic platform for controlled culture and analysis of unicellular organisms.

PubMed

Geng, Tao; Smallwood, Chuck R; Bredeweg, Erin L; Pomraning, Kyle R; Plymale, Andrew E; Baker, Scott E; Evans, James E; Kelly, Ryan T

2017-09-01

Modern live-cell imaging approaches permit real-time visualization of biological processes, yet limitations exist for unicellular organism isolation, culturing, and long-term imaging that preclude fully understanding how cells sense and respond to environmental perturbations and the link between single-cell variability and whole-population dynamics. Here, we present a microfluidic platform that provides fine control over the local environment with the capacity to replace media components at any experimental time point, and provides both perfused and compartmentalized cultivation conditions depending on the valve configuration. The functionality and flexibility of the platform were validated using both bacteria and yeast having different sizes, motility, and growth media. The demonstrated ability to track the growth and dynamics of both motile and non-motile prokaryotic and eukaryotic organisms emphasizes the versatility of the devices, which should enable studies in bioenergy and environmental research.

Phenotypic plasticity as an adaptation to a functional trade-off

PubMed Central

Yi, Xiao; Dean, Antony M

2016-01-01

We report the evolution of a phenotypically plastic behavior that circumvents the hardwired trade-off that exists when resources are partitioned between growth and motility in Escherichia coli. We propagated cultures in a cyclical environment, alternating between growth up to carrying capacity and selection for chemotaxis. Initial adaptations boosted overall swimming speed at the expense of growth. The effect of the trade-off was subsequently eased through a change in behavior; while individual cells reduced motility during exponential growth, the faction of the population that was motile increased as the carrying capacity was approached. This plastic behavior was produced by a single amino acid replacement in FliA, a regulatory protein central to the chemotaxis network. Our results illustrate how phenotypic plasticity potentiates evolvability by opening up new regions of the adaptive landscape. DOI: http://dx.doi.org/10.7554/eLife.19307.001 PMID:27692064

Oblique transport of gyrotactic microorganisms and bioconvection nanoparticles with convective mass flux

NASA Astrophysics Data System (ADS)

Iqbal, Z.; Mehmood, Zaffar; Maraj, E. N.

2017-04-01

The present study deals with examination of steady two dimensional nanofluid containing both nanoparticles and gyrotactic microorganisms. Moreover the study comprises stagnation point flow of an obliquely striking nanofluid. The governing partial differential equations are complex and highly non-linear in nature. These are converted into system of ordinary differential equations using suitable transformations. The system is then solved numerically using shooting technique with Runge - Kutta Fehlberg method of order 5. Further, effect of different physical parameters on velocity f ‧ (η) , temperature θ (η) , density of motile microorganisms w (η) and concentration ϕ (η) along with skin friction coefficient Cf, local Nusselt Nux, Sherwood Shx and density of motile microorganism Nnx numbers have been discussed through graphs and tables. Results depict that temperature, concentration, density of motile microorganisms and local Nusselt number are increasing functions of thermophoresis parameter Nt. Whereas Nt contributes in lessening Sherwood and local density numbers.

Redox reaction triggered nanomotors based on soft-oxometalates with high and sustained motility

NASA Astrophysics Data System (ADS)

Mallick, Apabrita; Laskar, Abhrajit; Adhikari, R.; Roy, Soumyajit

2018-05-01

The recent interest in self-propulsion raises an immediate challenge in facile and single-step synthesis of active particles. Here, we address this challenge and synthesize soft oxometalate nanomotors that translate ballistically in water using the energy released in a redox reaction of hydrazine fuel with the soft-oxometalates. Our motors reach a maximum speed of ̴ 370 body lengths per second and remain motile over a period of approximately three days. We report measurements of the speed of a single motor as a function of the concentration of hydrazine. It is also possible to induce a transition from single-particle translation to collective motility with biomimetic bands simply by tuning the loading of the fuel. We rationalize the results from a physicochemical hydrodynamic theory. Our nanomotors may also be used for transport of catalytic materials in harsh chemical environments that would otherwise passivate the active catalyst.

Microfabricated systems and assays for studying the cytoskeletal organization, micromechanics, and motility patterns of cancerous cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huda, Sabil; Pilans, Didzis; Makurath, Monika

Cell motions are driven by coordinated actions of the intracellular cytoskeleton – actin, microtubules (MTs) and substrate/focal adhesions (FAs). This coordination is altered in metastatic cancer cells resulting in deregulated and increased cellular motility. Microfabrication tools, including photolithography, micromolding, microcontact printing, wet stamping and microfluidic devices have emerged as a powerful set of experimental tools with which to probe and define the differences in cytoskeleton organization/dynamics and cell motility patterns in non-metastatic and metastatic cancer cells. In this paper, we discuss four categories of microfabricated systems: (i) micropatterned substrates for studying of cell motility sub-processes (for example, MT targeting ofmore » FAs or cell polarization); (ii) systems for studying cell mechanical properties, (iii) systems for probing overall cell motility patterns within challenging geometric confines relevant to metastasis (for example, linear and ratchet geometries), and (iv) microfluidic devices that incorporate co-cultures of multiple cell types and chemical gradients to mimic in vivo intravasation/extravasation steps of metastasis. Finally, together, these systems allow for creating controlled microenvironments that not only mimic complex soft tissues, but are also compatible with live cell high-resolution imaging and quantitative analysis of single cell behavior.« less

Microfabricated systems and assays for studying the cytoskeletal organization, micromechanics, and motility patterns of cancerous cells

DOE PAGES

Huda, Sabil; Pilans, Didzis; Makurath, Monika; ...

2014-08-28

Cell motions are driven by coordinated actions of the intracellular cytoskeleton – actin, microtubules (MTs) and substrate/focal adhesions (FAs). This coordination is altered in metastatic cancer cells resulting in deregulated and increased cellular motility. Microfabrication tools, including photolithography, micromolding, microcontact printing, wet stamping and microfluidic devices have emerged as a powerful set of experimental tools with which to probe and define the differences in cytoskeleton organization/dynamics and cell motility patterns in non-metastatic and metastatic cancer cells. In this paper, we discuss four categories of microfabricated systems: (i) micropatterned substrates for studying of cell motility sub-processes (for example, MT targeting ofmore » FAs or cell polarization); (ii) systems for studying cell mechanical properties, (iii) systems for probing overall cell motility patterns within challenging geometric confines relevant to metastasis (for example, linear and ratchet geometries), and (iv) microfluidic devices that incorporate co-cultures of multiple cell types and chemical gradients to mimic in vivo intravasation/extravasation steps of metastasis. Finally, together, these systems allow for creating controlled microenvironments that not only mimic complex soft tissues, but are also compatible with live cell high-resolution imaging and quantitative analysis of single cell behavior.« less

Effects of a long-day light programme on the motility and membrane integrity of cooled-stored and cyropreserved semen in Shetland pony stallions.

PubMed

Deichsel, Katharina; Schrammel, Nadine; Aurich, Jörg; Aurich, Christine

2016-04-01

Increasing day length in spring stimulates reproductive functions in horses. In this study, we have analysed the effect of artificial long days on the quality of cooled-stored and cryopreserved semen in Shetland stallions. Stallions of the treatment group (AL, n = 8) were exposed to 16 h light and 8h darkness from 15th December to 20th March while control stallions (CON, n = 7) were kept under natural photoperiod. Semen was collected once weekly and processed for cooled-storage and cryopreservation once per month. Total and progressive motility and percentage of membrane intact spermatozoa were analysed at 24, 48 and 72 h of cooled-storage and after freezing-thawing, respectively. Total and progressive motility and membrane integrity decreased during cooled-storage for 72 h in each month and both groups (p < 0.001). All these parameters were lower in CON versus AL stallions (p < 0.05) and the decrease was more pronounced in group CON (storage time x group p < 0.05). Differences between groups decreased throughout the observation period from January (p < 0.05 between groups) to July (e.g. total motility after 72 h of cooled-storage in January for group AL 80 ± 3 and group CON 49 ± 12%, respective values in July, 83 ± 2 and 72 ± 6%). Neither total and progressive motility nor percentage of membrane-intact and morphologically defect spermatozoa in frozen-thawed semen differed between groups and months. In conclusion, motility of cooled-stored semen was reduced in January and increased in stallions kept under a long day light programme for at least 30 days. Copyright © 2016 Elsevier B.V. All rights reserved.

The paradoxical relationship between stallion fertility and oxidative stress.

PubMed

Gibb, Zamira; Lambourne, Sarah R; Aitken, Robert J

2014-09-01

The relationship between stallion fertility and oxidative stress remains poorly understood. The purpose of this study was to identify criteria for thoroughbred fertility assessment by performing a logistical regression analysis using "dismount" sperm parameters as predictors and weekly per-cycle conception rate as the dependent variable. Paradoxically, positive relationships between fertility and oxidative stress were revealed, such that samples that produced pregnancies exhibited higher rates of 8-hydroxy-2'-deoxyguanosine release (1490.2% vs. 705.5 pg/ml/24 h) and lower vitality (60.5% vs. 69.6%) and acrosome integrity (40.2% vs. 50.1%) than those that did not. We hypothesized that the most fertile spermatozoa exhibited the highest levels of oxidative phosphorylation (OXPHOS), with oxidative stress simply being a by-product of intense mitochondrial activity. Accordingly, an experiment to investigate the relationship between oxidative stress and motility was conducted and revealed positive correlations between mitochondrial ROS and total motility (R² = 0.90), rapid motility (R² = 0.89), average path velocity (VAP; R² = 0.59), and curvilinear velocity (VCL; R² = 0.66). Similarly, lipid peroxidation was positively correlated with total motility (R² = 0.46), rapid motility (R² = 0.51), average path velocity (R² = 0.62), and VCL (R² = 0.56), supporting the aforementioned hypothesis. The relative importance of OXPHOS in supporting the motility of equine spermatozoa was contrasted with human spermatozoa, which primarily utilize glycolysis. In this study, mitochondrial inhibition significantly reduced the velocity (P < 0.01) and ATP (P < 0.05) content of equine, but not human, spermatozoa, emphasizing the former's relative dependence on OXPHOS. The equine is the first mammal in which such a positive relationship between oxidative stress and functionality has been observed, with implications for the management of stallion fertility in vitro and in vivo. © 2014 by the Society for the Study of Reproduction, Inc.

Motility alterations in celiac disease and non-celiac gluten sensitivity.

PubMed

Pinto-Sanchez, Maria Ines; Bercik, Premysl; Verdu, Elena F

2015-01-01

Regulation of gut motility is complex and involves neuromuscular, immune and environmental mechanisms. It is well established that patients with celiac disease (CD) often display gut dysmotility. Studies have shown the presence of disturbed esophageal motility, altered gastric emptying, and dysmotility of the small intestine, gallbladder and colon in untreated CD. Most of these motor abnormalities resolve after a strict gluten-free diet, suggesting that mechanisms related to the inflammatory condition and disease process are responsible for the motor dysfunction. Motility abnormalities are also a hallmark of functional bowel disorders such as irritable bowel syndrome (IBS), where it has been proposed as underlying mechanism for symptom generation (diarrhea, constipation, bloating). Non-celiac gluten sensitivity (NCGS) is a poorly defined entity, mostly self-diagnosed, that presents clinically with IBS symptoms in the absence of specific celiac markers. Patients with NCGS are believed to react symptomatically to wheat components, and some studies have proposed the presence of low-grade inflammation in these patients. There is little information regarding the functional characterization of these patients before and after a gluten-free diet. A study suggested the presence of altered gastrointestinal transit in NCGS patients who also have a high prevalence of nonspecific anti-gliadin antibodies. Results of an ongoing clinical study in NCGS patients with positive anti-gliadin antibodies before and after a gluten-free diet will be discussed. Elucidating the mechanisms for symptom generation in NCGS patients is important to find new therapeutic alternatives to the burden of imposing a strict gluten-free diet in patients who do not have CD. © 2015 S. Karger AG, Basel.

Role of hydrogen sulfide within the dorsal motor nucleus of the vagus in the control of gastric function in rats.

PubMed

Sun, H-Z; Yu, K-H; Ai, H-B

2015-05-01

Hydrogen sulfide (H2 S) is a gaseous messenger and serves as an important neuromodulator in the central nervous system. This study aimed to clarify the role of H2 S within the dorsal motor nucleus of the vagus (DMV) in the control of gastric function in rats. Cystathionine β-synthetase (CBS) is an important generator of endogenous H2 S in the brain. We investigated the distribution of CBS in the DMV using immunohistochemical method, and the effects of H2 S on gastric motility and on gastric acid secretion. CBS-immunoreactive (IR) neurons were detected in the rostral, intermediate and caudal DMV, with the highest number of CBS-IR neurons in the caudal DMV, and the lowest in the intermediate DMV. We also found that microinjection of the exogenous H2 S donor NaHS (0.04 and 0.08 mol/L; 0.1 μL; n = 6; p < 0.05) into the DMV significantly inhibited gastric motility with a dose-dependent trend, and promoted gastric acid secretion in Wistar rats. Microinjection of the same volume of physiological saline (PS; 0.1 μL, n = 6, p > 0.05) at the same location did not noticeably change gastric motility and acid secretion. The data from these experiments suggest that the CBS that produces H2 S is present in the DMV, and microinjection of NaHS into the DMV inhibited gastric motility and enhanced gastric acid secretion in rats. © 2015 John Wiley & Sons Ltd.

Acotiamide hydrochloride (Z-338), a new selective acetylcholinesterase inhibitor, enhances gastric motility without prolonging QT interval in dogs: comparison with cisapride, itopride, and mosapride.

PubMed

Matsunaga, Yugo; Tanaka, Takao; Yoshinaga, Koji; Ueki, Shigeru; Hori, Yuko; Eta, Runa; Kawabata, Yoshihiro; Yoshii, Kazuyoshi; Yoshida, Kenji; Matsumura, Toshihiro; Furuta, Shigeru; Takei, Mineo; Tack, Jan; Itoh, Zen

2011-03-01

Acotiamide hydrochloride (acotiamide; N-[2-[bis(1-methylethyl) amino]ethyl]-2-[(2-hydroxy-4,5-dimethoxybenzoyl) amino] thiazole-4-carboxamide monohydrochloride trihydrate, Z-338) has been reported to improve meal-related symptoms of functional dyspepsia in clinical studies. Here, we examined the gastroprokinetic effects of acotiamide and its antiacetylcholinesterase activity as a possible mechanism of action in conscious dogs. Acotiamide increased postprandial gastric motor activity in conscious dogs with chronically implanted force transducers and, like itopride, mosapride, and cisapride, exhibited gastroprokinetic activity in these dogs. Furthermore, acotiamide improved clonidine-induced hypomotility and delayed gastric emptying. Acotiamide-enhanced postprandial gastroduodenal motility was suppressed completely by pretreatment with atropine, a muscarinic receptor antagonist. In in vitro studies, acotiamide enhanced acetylcholine- but not carbachol-induced contractile responses of guinea pig gastric antrum strips. Moreover, like itopride and neostigmine, acotiamide inhibited recombinant human and canine stomach-derived acetylcholinesterase (AChE) activity in vitro. The mode of the AChE inhibitory action of acotiamide was selective and reversible. Unlike itopride or mosapride, acotiamide showed no affinity for dopamine D(2) or serotonin 5-HT(4) receptors. With regard to cardiovascular side effects, unlike cisapride, acotiamide did not affect myocardial monophasic action potential duration, QT interval, or corrected QT interval in anesthetized dogs. These results suggest that acotiamide stimulates gastric motility in vivo by inhibiting AChE activity without affecting QT interval. Acotiamide thus represents a beneficial new drug for the treatment of functional dyspepsia involving gastric motility dysfunction, with differences from other prokinetic agents.

Correlation between colonic secretion and colonic motility in rats: Role of ghrelin

PubMed Central

Huang, Hsien-Hao; Ting, Ching-Heng; Syu, Yu-Fong; Chang, Shi-Chuan; Chen, Chih-Yen

2016-01-01

AIM To explore the relationship between colonic secretory function and colonic motility. METHODS Using a rat model chronically implanted with intracerebroventricular (ICV) and cecal catheters, we validated the correlation between colonic secretion and colonic motor functions, as well as the role of ICV injection volume. RESULTS Compared to saline controls (5 μL/rat), ICV acyl ghrelin at 1 nmol/5 μL enhanced the total fecal weight, accelerated the colonic transit time, and increased the fecal pellet output during the first hour post-injection, while ICV des-acyl ghrelin at 1 nmol/5 μL only accelerated the colonic transit time. These stimulatory effects on colonic motility and/or secretion from acyl ghrelin and des-acyl ghrelin disappeared when the ICV injection volume increased to 10 μL compared with saline controls (10 μL/rat). Additionally, the ICV injection of 10 μL of saline significantly shortened the colonic transit time compared with the ICV injection of 5 μL of saline. The total fecal weight during the first hour post-injection correlated with the colonic transit time and fecal pellet output after the ICV injection of acyl ghrelin (1 nmol/5 μL), whereas the total fecal weight during the first hour post-injection correlated with the fecal pellet output but not the colonic transit time after the ICV injection of des-acyl ghrelin (1 nmol/5 μL). CONCLUSION Colonic secretion does not always correlate with colonic motility in response to different colonic stimulations. Acyl ghrelin stimulates colonic secretion. PMID:28028362

Differential dynamic microscopy to characterize Brownian motion and bacteria motility

NASA Astrophysics Data System (ADS)

Germain, David; Leocmach, Mathieu; Gibaud, Thomas

2016-03-01

We have developed a lab module for undergraduate students, which involves the process of quantifying the dynamics of a suspension of microscopic particles using Differential Dynamic Microscopy (DDM). DDM is a relatively new technique that constitutes an alternative method to more classical techniques such as dynamic light scattering (DLS) or video particle tracking (VPT). The technique consists of imaging a particle dispersion with a standard light microscope and a camera and analyzing the images using a digital Fourier transform to obtain the intermediate scattering function, an autocorrelation function that characterizes the dynamics of the dispersion. We first illustrate DDM in the textbook case of colloids under Brownian motion, where we measure the diffusion coefficient. Then we show that DDM is a pertinent tool to characterize biological systems such as motile bacteria.

Fungal lectin of Peltigera canina induces chemotropism of compatible Nostoc cells by constriction-relaxation pulses of cyanobiont cytoskeleton.

PubMed

Díaz, Eva Maria; Vicente-Manzanares, Miguel; Sacristan, Mara; Vicente, Carlos; Legaz, Maria-Estrella

2011-10-01

A glycosylated arginase acting as a fungal lectin from Peltigera canina is able to produce recruitment of cyanobiont Nostoc cells and their adhesion to the hyphal surface. This implies that the cyanobiont would develop organelles to motility towards the chemoattractant. However when visualized by transmission electron microscopy, Nostoc cells recently isolated from P. canina thallus do not reveal any motile, superficial organelles, although their surface was covered by small spindles and serrated layer related to gliding. The use of S-(3,4-dichlorobenzyl)isothiourea, blebbistatin, phalloidin and latrunculin A provide circumstantial evidence that actin microfilaments rather than MreB, the actin-like protein from prokaryota, and, probably, an ATPase which develops contractile function similar to that of myosin II, are involved in cell motility. These experimental facts, the absence of superficial elements (fimbriae, pili or flagellum) related to cell movement, and the appearance of sunken cells during of after movement verified by scanning electron microscopy, support the hypothesis that the motility of lichen cyanobionts could be achieved by contraction-relaxation episodes of the cytoskeleton induced by fungal lectin act as a chemoattractant.

Fungal lectin of Peltigera canina induces chemotropism of compatible Nostoc cells by constriction-relaxation pulses of cyanobiont cytoskeleton

PubMed Central

Díaz, Eva Maria; Vicente-Manzanares, Miguel; Sacristan, Mara; Legaz, Maria-Estrella

2011-01-01

A glycosylated arginase acting as a fungal lectin from Peltigera canina is able to produce recruitment of cyanobiont Nostoc cells and their adhesion to the hyphal surface. This implies that the cyanobiont would develop organelles to motility toward the chemoattractant. However when visualized by transmission electron microscopy, Nostoc cells recently isolated from P. canina thallus do not reveal any motile, superficial organelles, although their surface was covered by small spindles and serrated layer related to gliding. The use of S-(3,4-dichlorobenzyl)isothiourea, blebbistatin, phalloidin and latrunculin A provide circumstantial evidence that actin microfilaments rather than MreB, the actin-like protein from prokaryota, and probably, an ATPase which develops contractile function similar to that of myosin II, are involved in cell motility. These experimental facts, the absence of superficial elements (fimbriae, pili or flagellum) related to cell movement, and the appearance of sunken cells during of after movement verified by scanning electron microscopy, support the hypothesis that the motility of lichen cyanobionts could be achieved by contraction-relaxation episodes of the cytoskeleton induced by fungal lectin act as a chemoattractant. PMID:21897128

T Lymphocyte Migration: An Action Movie Starring the Actin and Associated Actors.

PubMed

Dupré, Loïc; Houmadi, Raïssa; Tang, Catherine; Rey-Barroso, Javier

2015-01-01

The actin cytoskeleton is composed of a dynamic filament meshwork that builds the architecture of the cell to sustain its fundamental properties. This physical structure is characterized by a continuous remodeling, which allows cells to accomplish complex motility steps such as directed migration, crossing of biological barriers, and interaction with other cells. T lymphocytes excel in these motility steps to ensure their immune surveillance duties. In particular, actin cytoskeleton remodeling is a key to facilitate the journey of T lymphocytes through distinct tissue environments and to tune their stop and go behavior during the scanning of antigen-presenting cells. The molecular mechanisms controlling actin cytoskeleton remodeling during T lymphocyte motility have been only partially unraveled, since the function of many actin regulators has not yet been assessed in these cells. Our review aims to integrate the current knowledge into a comprehensive picture of how the actin cytoskeleton drives T lymphocyte migration. We will present the molecular actors that control actin cytoskeleton remodeling, as well as their role in the different T lymphocyte motile steps. We will also highlight which challenges remain to be addressed experimentally and which approaches appear promising to tackle them.

Seasonal effects on seminal and endocrine traits in the captive snow leopard (Panthera uncia).

PubMed

Johnston, L A; Armstrong, D L; Brown, J L

1994-09-01

The annual reproductive cycle of the male snow leopard (Panthera uncia) was characterized by evaluating seminal and endocrine traits monthly. Testicular volume was greatest (P < 0.05) during the winter months when the quality of ejaculate was optimal. Ejaculate volume, total sperm concentration ml-1, motile sperm concentration per ejaculate, sperm morphology and sperm motility index were lowest during the summer and autumn months compared with the winter and spring. Peripheral LH, FSH and testosterone concentrations were also lowest during the summer months, increasing during the autumn just before the increase in semen quality, and were maximal during the winter months. There was a direct relationship (P < 0.01) between: (1) testosterone and testicular volume, total sperm concentration ml-1, motile sperm concentration per ejaculate and ejaculate volume, and (2) LH and testicular volume and motile sperm concentration per ejaculate. In summary, although spermatozoa were recovered throughout the year, optimal gamete quality was observed during the winter and spring. Although previous studies in felids have demonstrated seasonal effects on either seminal or endocrine traits, this is the first study to demonstrate a distinct effect of season on both pituitary and testicular function.

Automated motile cell capture and analysis with optical traps.

PubMed

Shao, Bing; Nascimento, Jaclyn M; Shi, Linda Z; Botvinick, Elliot L

2007-01-01

Laser trapping in the near infrared regime is a noninvasive and microfluidic-compatible biomedical tool. This chapter examines the use of optical trapping as a quantitative measure of sperm motility. The single point gradient trap is used to directly measure the swimming forces of sperm from several different species. These forces could provide useful information about the overall sperm motility and semen quality. The swimming force is measured by trapping sperm and subsequently decreasing laser power until the sperm is capable of escaping the trap. Swimming trajectories were calculated by custom built software, an automatic sperm tracking algorithm called the single sperm tracking algorithm or SSTA. A real-time automated tracking and trapping system, or RATTS, which operates at video rate, was developed to perform experiments with minimal human involvement. After the experimenter initially identifies and clicks the computer mouse on the sperm-of-interest, RATTS performs all further tracking and trapping functions without human intervention. Additionally, an annular laser trap which is potentially useful for high-throughput sperm sorting based on motility and chemotaxis was developed. This low power trap offers a more gentle way for studying the effects of laser radiation, optical force, and external obstacles on sperm swimming pattern.

Human sperm NADH and NADPH diaphorase cytochemistry: correlation with sperm motility.

PubMed

Zini, A; O'Bryan, M K; Israel, L; Schlegel, P N

1998-03-01

We have examined the correlation between the retention of residual sperm cytoplasm and sperm motility in semen from men presenting for infertility evaluation. Semen samples (n = 12) were obtained from nonazoospermic men presenting for infertility evaluation at our institution. Samples were fractionated into high-, intermediate-, and low-density subpopulations by Percoll gradients in order to examine the correlation between the retention of residual sperm cytoplasm and sperm motility. Residual sperm cytoplasm retention was detected by cytochemical staining of sperm for nicotinamide adenine dinucleotide (NADH)- or nicotinamide adenine dinucleotide phosphate (NADPH)-dependent diaphorase activity. The different sperm subpopulations (low, intermediate, and high density) had significantly different percentages of sperm with droplet retention (analysis of variance, P < 0.05). Using either NADH or NADPH diaphorase staining as a marker of the cytoplasmic space, a significant negative correlation was observed between the percentage of sperm with residual cytoplasmic droplets and the percentage of motile sperm (r = -0.58 and -0.61, respectively, P < 0.05). Assessment of residual sperm cytoplasm retention is a simple diagnostic test. Although this test is of unproven value in the management of infertile men, this and other studies suggest that it may provide useful data on sperm function.

Pharyngeal swallowing and oesophageal motility during a solid meal test: a prospective study in healthy volunteers and patients with major motility disorders.

PubMed

Hollenstein, Michael; Thwaites, Philip; Bütikofer, Simon; Heinrich, Henriette; Sauter, Matthias; Ulmer, Irina; Pohl, Daniel; Ang, Daphne; Eberli, Daniel; Schwizer, Werner; Fried, Michael; Distler, Oliver; Fox, Mark; Misselwitz, Benjamin

2017-09-01

The factors that determine how people eat when they are healthy or have disease have not been defined. We used high resolution manometry (HRM) to assess pharyngeal swallowing and oesophageal motility during ingestion of a solid test meal (STM) in healthy volunteers and patients with motility disorders. This study was based at University Hospital Zurich (Zürich, Switzerland). Healthy volunteers who responded to an advertisement completed HRM with ten single water swallows (SWS) in recumbent and upright positions followed by a 200 g rice STM in the upright position. Healthy volunteers were stratified for age and sex to ensure a representative population. For comparison, consecutive patients with major motility disorders on SWS and patients with dysphagia but no major motility disorders on SWS (disease controls) were selected from a database that was assembled prospectively; the rice meal data were analysed retrospectively. During STM, pharyngeal swallows were timed and oesophageal contractions were classified as representing normal motility or different types of abnormal motility in accordance with established metrics. Factors that could potentially be associated with eating speed were investigated, including age, sex, body-mass index, and presence of motility disorder. We compared diagnoses based on SWS findings, assessed with the Chicago Classification v3.0, with those based on STM findings, assessed with the Chicago Classification adapted for solids. These studies are registered with ClinicalTrials.gov, numbers NCT02407938 and NCT02397616. Between April 2, 2014, and May 13, 2015, 72 healthy volunteers were recruited and underwent HRM. Additionally, we analysed data from 54 consecutive patients with major motility disorders and 53 with dysphagia but no major motility disorders recruited between April 2, 2013, and Dec 18, 2014. We found important variations in oesophageal motility and eating speed during meal ingestion in healthy volunteers and patients. Increased time between swallows was accompanied by more effective oesophageal contractions (in healthy volunteers, 20/389 [5%] effective swallows at <4 s between swallows vs 586/900 [65%] effective swallows at >11 s between swallows, p<0·0001). Obstructive, spastic, or hypercontractile swallows were rare in healthy volunteers (total <1%). Patients with motility disorders ate slower than healthy volunteers (14·95 g [IQR 11-25] per min vs 32·9 g [25-40] per min, p<0·0001) and pathological oesophageal motility were reproduced when patients consumed the STM. In healthy volunteers, eating speed was associated only with frequency of swallows (slope 2·5 g per min per pharyngeal swallow per min [95% CI 1·1-4·0], p=0·0009), whereas in patients with dysphagia, it was correlated with frequency of effective oesophageal contractions (6·4 g per min per effective contraction per min [4·3-8·5], p<0·0001). Diagnostic agreement was good between the HRM with SWS and rice STM (intra-class correlation coefficient r=0·81, 95% CI 0·74-0·87, p<0·0001). Our results show normative values for pharyngeal swallowing and oesophageal motility in healthy volunteers. Detailed analysis of HRM data acquired during an STM shows that the rate-limiting factor for intake of solids in health is the frequency of pharyngeal swallowing and not oesophageal contractility. The reverse is true in patients with oesophageal motility disorders, in whom the frequency of effective oesophageal contractions determines eating speed. University Hospital Zurich. Copyright © 2017 Elsevier Ltd. All rights reserved.

Staring at the cold sun: blue light regulation is distributed within the genus Acinetobacter.

PubMed

Golic, Adrián; Vaneechoutte, Mario; Nemec, Alexandr; Viale, Alejandro M; Actis, Luis A; Mussi, María Alejandra

2013-01-01

We previously showed that the opportunistic nosocomial pathogen Acinetobacter baumannii is able to sense and respond to light via BlsA, a BLUF (Blue-Light-sensing Using FAD)-domain photoreceptor protein. Here, we extend our previous studies showing that light regulation is not restricted to A. baumannii, but rather widespread within the genus Acinetobacter. First, we found that blue light modulates motility and biofilm formation in many species of the genus, including members of the Acinetobacter calcoaceticus-A. baumannii complex. In many of these species blue light acts as a key factor guiding the decision between motility or sessility at 24°C, whereas in A. baumannii, light inhibits both motility and biofilm formation. We also show that light regulation of motility occurred not only at 24°C but also at 37°C in non-A. baumannii species, contrasting the situation of A. baumannii which only shows photoregulation at 24°C. Second, we show that Acinetobacter baylyi (strain ADP1) BLUF-photoreceptors can functionally replace in vivo the A. baumannii 17978 BlsA protein and that the pathways leading to biofilm formation are inversely regulated at 24°C between these two microorganisms. Finally, we found the presence of predicted genes coding BLUF-containing proteins in all Acinetobacter sequenced genomes, even though the copy number is variable among them. Phylogenetic analysis suggests a common origin for all BLUF domains present in members of this genus, and could distinguish well-differentiated clusters that group together BLUF homologs from different species, a situation particularly clear for members of the ACB complex. Despite a role played by these BLUF domain-containing proteins in the photoregulation observed in the members of the genus Acinetobacter is a likely scenario given our findings in A. baumannii and A. baylyi, further research will contribute to confirm this possibility.

Staring at the Cold Sun: Blue Light Regulation Is Distributed within the Genus Acinetobacter

PubMed Central

Golic, Adrián; Vaneechoutte, Mario; Nemec, Alexandr; Viale, Alejandro M.; Actis, Luis A.; Mussi, María Alejandra

2013-01-01

We previously showed that the opportunistic nosocomial pathogen Acinetobacter baumannii is able to sense and respond to light via BlsA, a BLUF (Blue-Light-sensing Using FAD)-domain photoreceptor protein. Here, we extend our previous studies showing that light regulation is not restricted to A. baumannii, but rather widespread within the genus Acinetobacter. First, we found that blue light modulates motility and biofilm formation in many species of the genus, including members of the Acinetobacter calcoaceticus-A. baumannii complex. In many of these species blue light acts as a key factor guiding the decision between motility or sessility at 24°C, whereas in A. baumannii, light inhibits both motility and biofilm formation. We also show that light regulation of motility occurred not only at 24°C but also at 37°C in non-A. baumannii species, contrasting the situation of A. baumannii which only shows photoregulation at 24°C. Second, we show that Acinetobacter baylyi (strain ADP1) BLUF-photoreceptors can functionally replace in vivo the A. baumannii 17978 BlsA protein and that the pathways leading to biofilm formation are inversely regulated at 24°C between these two microorganisms. Finally, we found the presence of predicted genes coding BLUF-containing proteins in all Acinetobacter sequenced genomes, even though the copy number is variable among them. Phylogenetic analysis suggests a common origin for all BLUF domains present in members of this genus, and could distinguish well-differentiated clusters that group together BLUF homologs from different species, a situation particularly clear for members of the ACB complex. Despite a role played by these BLUF domain-containing proteins in the photoregulation observed in the members of the genus Acinetobacter is a likely scenario given our findings in A. baumannii and A. baylyi, further research will contribute to confirm this possibility. PMID:23358859

The Anoikis Effector Bit1 Inhibits EMT through Attenuation of TLE1-Mediated Repression of E-Cadherin in Lung Cancer Cells

PubMed Central

Yao, Xin; Pham, Tri; Temple, Brandi; Gray, Selena; Cannon, Cornita; Chen, Renwei; Abdel-Mageed, Asim B.; Biliran, Hector

2016-01-01

The mitochondrial Bcl-2 inhibitor of transcription 1 (Bit1) protein is part of an anoikis-regulating pathway that is selectively dependent on integrins. We previously demonstrated that the caspase-independent apoptotic effector Bit1 exerts tumor suppressive function in lung cancer in part by inhibiting anoikis resistance and anchorage-independent growth in vitro and tumorigenicity in vivo. Herein we show a novel function of Bit1 as an inhibitor cell migration and epithelial–mesenchymal transition (EMT) in the human lung adenocarcinoma A549 cell line. Suppression of endogenous Bit1 expression via siRNA and shRNA strategies promoted mesenchymal phenotypes, including enhanced fibroblastoid morphology and cell migratory potential with concomitant downregulation of the epithelial marker E-cadherin expression. Conversely, ectopic Bit1 expression in A549 cells promoted epithelial transition characterized by cuboidal-like epithelial cell phenotype, reduced cell motility, and upregulated E-cadherin expression. Specific downregulation of E-cadherin in Bit1-transfected cells was sufficient to block Bit1-mediated inhibition of cell motility while forced expression of E-cadherin alone attenuated the enhanced migration of Bit1 knockdown cells, indicating that E-cadherin is a downstream target of Bit1 in regulating cell motility. Furthermore, quantitative real-time PCR and reporter analyses revealed that Bit1 upregulates E-cadherin expression at the transcriptional level through the transcriptional regulator Amino-terminal Enhancer of Split (AES) protein. Importantly, the Bit1/AES pathway induction of E-cadherin expression involves inhibition of the TLE1-mediated repression of E-cadherin, by decreasing TLE1 corepressor occupancy at the E-cadherin promoter as revealed by chromatin immunoprecipitation assays. Consistent with its EMT inhibitory function, exogenous Bit1 expression significantly suppressed the formation of lung metastases of A549 cells in an in vivo experimental metastasis model. Taken together, our studies indicate Bit1 is an inhibitor of EMT and metastasis in lung cancer and hence can serve as a molecular target in curbing lung cancer aggressiveness. PMID:27655370

PAR-2-mediated control of barrier function and motility differs between early and late phases of postinfectious gut dysfunction in the rat.

PubMed

Fernández-Blanco, Joan Antoni; Fernández-Blanco, Juan A; Hollenberg, Morley D; Martínez, Vicente; Vergara, Patri

2013-02-15

Proteinase-activated receptor-2 (PAR-2) and mast cell (MC) mediators contribute to inflammatory and functional gastrointestinal disorders. We aimed to characterize jejunal PAR-2-mediated responses and the potential MC involvement in the early and late phases of a rat model of postinfectious gut dysfunction. Jejunal tissues of control and Trichinella spiralis-infected (14 and 30 days postinfection) rats, treated or not with the MC stabilizer, ketotifen, were used. Histopathology and immunostaining were used to characterize inflammation, PAR-2 expression, and mucosal and connective tissue MCs. Epithelial barrier function (hydroelectrolytic transport and permeability) and motility were assessed in vitro in basal conditions and after PAR-2 activation. Intestinal inflammation on day 14 postinfection (early phase) was significantly resolved by day 30 (late phase) although MC counts and epithelial permeability remained increased. PAR-2-mediated ion transport (Ussing chambers, in vitro) and epithelial surface PAR-2 expression were reduced in the early phase, with a trend toward normalization during the late phase. In control conditions, PAR-2 activation (organ bath) induced biphasic motor responses (relaxation followed by excitation). At 14 days postinfection, spontaneous contractility and PAR-2-mediated relaxations were enhanced; motor responses were normalized on day 30. Postinfectious changes in PAR-2 functions were not affected by ketotifen treatment. We concluded that, in the rat model of Trichinella spiralis infection, alterations of intestinal PAR-2 function and expression depend on the inflammatory phase considered. A lack of a ketotifen effect suggests no interplay between MCs and PAR-2-mediated motility and ion transport alterations. These observations question the role of MC mediators in PAR-2-modulating postinfectious gut dysfunction.

Novel sex cells and evidence for sex pheromones in diatoms.

PubMed

Sato, Shinya; Beakes, Gordon; Idei, Masahiko; Nagumo, Tamotsu; Mann, David G

2011-01-01

Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy) and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments are the first studies in which gametogenesis has been induced in diatoms by cell-free exudates, opening new possibilities for molecular 'dissection' of sexualization.

Micromotors working in water through artificial aerobic metabolism

NASA Astrophysics Data System (ADS)

Yamamoto, D.; Takada, T.; Tachibana, M.; Iijima, Y.; Shioi, A.; Yoshikawa, K.

2015-07-01

Most catalytic micro/nanomotors that have been developed so far use hydrogen peroxide as fuel, while some use hydrazine. These fuels are difficult to apply because they can cause skin irritation, and often form and store disruptive bubbles. In this paper, we demonstrate a novel catalytic Pt micromotor that does not produce bubbles, and is driven by the oxidation of stable, non-toxic primary alcohols and aldehydes with dissolved oxygen. This use of organic oxidation mirrors living systems, and lends this new motor essentially the same characteristics, including decreased motility in low oxygen environments and the direct isothermal conversion of chemical energy into mechanical energy. Interestingly, the motility direction is reversed by replacing the reducing fuels with hydrogen peroxide. Therefore, these micromotors not only provide a novel system in nanotechnology, but also help in further revealing the underlining mechanisms of motility of living organisms.Most catalytic micro/nanomotors that have been developed so far use hydrogen peroxide as fuel, while some use hydrazine. These fuels are difficult to apply because they can cause skin irritation, and often form and store disruptive bubbles. In this paper, we demonstrate a novel catalytic Pt micromotor that does not produce bubbles, and is driven by the oxidation of stable, non-toxic primary alcohols and aldehydes with dissolved oxygen. This use of organic oxidation mirrors living systems, and lends this new motor essentially the same characteristics, including decreased motility in low oxygen environments and the direct isothermal conversion of chemical energy into mechanical energy. Interestingly, the motility direction is reversed by replacing the reducing fuels with hydrogen peroxide. Therefore, these micromotors not only provide a novel system in nanotechnology, but also help in further revealing the underlining mechanisms of motility of living organisms. Electronic supplementary information (ESI) available: Details of the experimental procedure, supplementary note S1, supplementary Fig. S1 to S5, and supplementary videos S1 to S4. See DOI: 10.1039/c5nr03300d

An extract of pomegranate fruit and galangal rhizome increases the numbers of motile sperm: a prospective, randomised, controlled, double-blinded trial.

PubMed

Fedder, Maja D K; Jakobsen, Henrik B; Giversen, Ina; Christensen, Lars P; Parner, Erik T; Fedder, Jens

2014-01-01

Pomegranate fruit (Punica granatum) and galangal (Alpinia galanga) have separately been shown to stimulate spermatogenesis and to increase sperm counts and motility in rodents. Within traditional medicine, pomegranate fruit has long been used to increase fertility, however studies on the effect on spermatogenesis in humans have never been published. With this study we investigated whether oral intake of tablets containing standardised amounts of extract of pomegranate fruit and powder of greater galangal rhizome (Punalpin) would increase the total number of motile spermatozoa. The study was designed as a prospective, randomized, controlled, double-blinded trial. Enrolment was based on the mean total number of motile spermatozoa of two ejaculates. The participants delivered an ejaculate after 4-8 days of tablet intake and two ejaculates just before they stopped taking the tablets. Seventy adult men with a semen quality not meeting the standards for commercial application at Nordic Cryobank, but without azoospermia, were included in the study. Participants were randomized to take tablets containing extract of pomegranate fruit (standardised with respect to punicalagin A+B, punicalin and ellagic acid) and freeze-dried rhizome of greater galangal (standardised with respect to 1'S-1'-acetoxychavicol acetate) or placebo on a daily basis for three months. Sixty-six participants completed the intervention (active treatment: n = 34; placebo: n = 32). After the intervention the total number of motile spermatozoa was increased in participants treated with plant extracts compared with the placebo group (p = 0.026). After three months of active treatment, the average total number of motile sperm increased by 62% (from 23.4 to 37.8 millions), while for the placebo group, the number of motile sperm increased by 20%. Sperm morphology was not affected by the treatment. Our findings may help subfertile men to gain an improved amount of motile ejaculated sperm by taking tablets containing preparations of pomegranate fruit extract and rhizome of greater galangal. ClinicalTrials.gov NCT01357044.

Cryopreservation of stallion spermatozoa using different cryoprotectants and combinations of cryoprotectants.

PubMed

Wu, Zhuangyuan; Zheng, Xinbiao; Luo, Yongming; Huo, Fei; Dong, Hong; Zhang, Guoting; Yu, Weihao; Tian, Fang; He, Liangjun; Chen, Jingbo

2015-12-01

The present study investigates the effects of five cryoprotectants (CPAs) and cryoprotectant combinations on the post-thaw total motility, progressive motility, viability, mitochondrial membrane potential and acrosome integrity in stallion spermatozoa. In Experiment 1, the objective was to compare the impact of different concentrations (2.5%, 3.5% and 5%) of a single CPA, including glycerol (Gly), ethylene glycol (EG), dimethyl sulphoxide (DMSO), methyl formamide (MF), and dimethylformamide (DMF) for stallion spermatozoa cryopreservation. In Experiment 2, two or more CPAs were used to assess whether this improved post-thaw spermatozoa quality. Gly, MF and DMF, were used to prepare seven combinations of freezing extender with different mixtures of cryoprotectant, and the 3.5% Gly, MF and DMF were used as a control group. The results show that post-thaw total motility, progressive motility, viability, and mitochondrial membrane potential for all concentrations of EG and DMSO were less than the 3.5% and 5% Gly and MF and 2.5% and 3.5% DMF (P<0.05). Use of the 3.5% concentration resulted in the greater post-thaw total motility and progressive motility than the 2.5% and 5% concentrations for all CPAs. The results for the use of different combinations of cryoprotectant indicate there are differences in progressive motility and viability. The viability with the use of Gly(2/3)+MF(1/3) was 44.65% and was greater than the Gly(1/3)+MF(1/3)+DMF(1/3) (30.96%), MF(2/3)+DMF(1/3) (35.05%), Gly (32.21%) and MF(33.76%) (P<0.05). The progressive motility with the use of the MF(2/3)+Gly(1/3) combination was 36.0% and was greater than in the DMF (25.0%) and MF(2/3)+DMF(1/3) (22.7%) (P<0.05). These results suggest that using the appropriate cryoprotectant combination instead of a single cryoprotectant can improve horse spermatozoa cryopreservation. Copyright © 2015 Elsevier B.V. All rights reserved.

Continuum models of cohesive stochastic swarms: The effect of motility on aggregation patterns

NASA Astrophysics Data System (ADS)

Hughes, Barry D.; Fellner, Klemens

2013-10-01

Mathematical models of swarms of moving agents with non-local interactions have many applications and have been the subject of considerable recent interest. For modest numbers of agents, cellular automata or related algorithms can be used to study such systems, but in the present work, instead of considering discrete agents, we discuss a class of one-dimensional continuum models, in which the agents possess a density ρ(x,t) at location x at time t. The agents are subject to a stochastic motility mechanism and to a global cohesive inter-agent force. The motility mechanisms covered include classical diffusion, nonlinear diffusion (which may be used to model, in a phenomenological way, volume exclusion or other short-range local interactions), and a family of linear redistribution operators related to fractional diffusion equations. A variety of exact analytic results are discussed, including equilibrium solutions and criteria for unimodality of equilibrium distributions, full time-dependent solutions, and transitions between asymptotic collapse and asymptotic escape. We address the behaviour of the system for diffusive motility in the low-diffusivity limit for both smooth and singular interaction potentials and show how this elucidates puzzling behaviour in fully deterministic non-local particle interaction models. We conclude with speculative remarks about extensions and applications of the models.

Expression of aquaporins in the efferent ductules, sperm counts, and sperm motility in estrogen receptor-alpha deficient mice fed lab chow versus casein.

PubMed

Ruz, Ricardo; Gregory, Mary; Smith, Charles E; Cyr, Daniel G; Lubahn, Dennis B; Hess, Rex A; Hermo, Louis

2006-02-01

Estrogens play an important role in the male reproductive tract, and this is especially so for the efferent ductules, where alpha-estrogen receptors (ERalpha) have been localized. Mice deficient in ERalpha (alphaERKO mice) are infertile, and the effect appears to be due in part to retention of water at the level of the efferent ductules. In the present study, we examined the consequences of ERalpha deletion on the distribution of certain aquaporins (AQPs), water protein channels, in the efferent ductules and on sperm numbers and motility. In addition, the effects of feeding mice a regular lab chow diet, which contains phytoestrogens, known to affect male reproductive tract functions, and a casein diet, which lacks phytoestrogens, were also assessed. Light microscope immunolocalizations of AQP-1 and AQP-9 revealed dramatic reduction and patchier staining in alphaERKO mice with distal areas of the efferent ductules being more affected than proximal areas. No other changes in immunolocalizations were noted as a consequence of diet. Computer-assisted sperm analyses demonstrated a 62% reduction in cauda epididymal sperm/ml in alphaERKO mice fed lab chow, whereas 87% fewer sperm/ml were observed in alphaERKO mice fed casein, suggesting an enhanced role for sperm production and concentration in a diet containing phytoestrogens. All sperm motility parameters were altered to some degree in alphaERKO mice fed lab chow. Alterations in sperm motility parameters were also detected, but were less dramatic in alphaERKO mice fed casein. These data suggest that the decrease in AQP expression in the efferent ductules of alphaERKO mice contributes in part to water retention in this tissue, eventually leading to backflow of water into the testis, with subsequent decreases in sperm concentration and motility. The data also suggest that phytoestrogens, which are present in regular lab chow, can influence the male reproductive tract with and without the presence of ERalpha, promoting efferent ductule and epididymal functions when ERalpha is expressed, but inhibiting these same functions when ERalpha is missing. Taken together the data underscore the importance of estrogens and ERalpha in maintaining sperm maturation and preventing male infertility. (c) 2005 Wiley-Liss, Inc.

Impact of thoracic surgery on esophageal motor function—Evaluation by high resolution manometry

PubMed Central

Kandulski, Arne; Malfertheiner, Peter; Riedel, Sandra; Zardo, Patrick; Hachenberg, Thomas; Schreiber, Jens

2017-01-01

Background Alteration of esophageal function is a potential risk factor for postoperative complications in thoracic surgery. This prospective study investigates esophageal motility and function during and after thoracic procedures via high resolution manometry (HRM) and impedance technology with spatiotemporal representation of pressure data. Methods Twelve consecutive patients eligible for elective thoracic surgery underwent preoperative and postoperative (48 hours and 7 days) esophageal HRM. Swallowing acts were carried out with 5 mL of water, 10 mL of water and 1 cm3 bread in physiological posture to evaluate distal contraction integral (DCI). Length and location of contractile integrity breaks were measured by investigators blinded to the form of surgical intervention. The impact of surgical procedures on esophageal motility was quantified according to current Chicago Classification (CC) criteria. Pre-, intra- and postoperative 24-hour multi-channel impedance pH–metry (MII-pH) was performed to further analyze gastroesophageal reflux patterns. Results All patients were investigated 48 hours prior to and 7 days after thoracic procedures, with a total of n=675 swallowing acts being included in our study. Increased motility patterns of the tubular esophagus occurred temporally 48 hours postoperatively. DCI 48 hours after surgery increased significantly (5 mL, P=0.049; solid, P=0.014) and returned to baseline values after seven days (5 mL, P=0.039; solid, P=0.039). Break length was significantly reduced 48 hours postoperatively, especially in the proximal esophageal segment (transition zone). Follow-up measurements after another week were comparable to preoperative baseline findings. The perioperative MII-pH measurement showed numerous artifacts caused by intubation and ventilation during surgery also with increasing short and frequent acidic reflux episodes. Conclusions Thoracic procedures cause a transient modulation of esophageal peristalsis with postoperative increased contractility of the tubular esophagus, presumably without affecting intraesophageal reflex arcs. Although limited by the number of patients, we can conclude on our data that postoperative esophageal hypomotility is unlikely to promote secondary pulmonary complications. PMID:28740669

Prucalopride decreases esophageal acid exposure and accelerates gastric emptying in healthy subjects.

PubMed

Kessing, B F; Smout, A J P M; Bennink, R J; Kraaijpoel, N; Oors, J M; Bredenoord, A J

2014-08-01

The 5-HT4 receptor agonist prucalopride is a prokinetic drug which improves colonic motility. Animal data and in vitro studies suggest that prucalopride also affects gastric and esophageal motor function. We aimed to assess the effect of prucalopride on gastric emptying, esophageal motility, and gastro-esophageal reflux in man. In this double-blind, placebo-controlled, randomized, crossover study, we included 21 healthy volunteers who received 4 mg prucalopride or placebo per day for 6 days. We performed high-resolution manometry (HRM) followed by 120-min HRM-pH-impedance monitoring after a standardized meal, ambulatory 24-h pH-impedance monitoring, and gastric emptying for solids. Prucalopride decreased (median [IQR]) total acid exposure time (3.4 [2.5-5.6] vs 1.7 [0.8-3.5] %, p < 0.05). The total number of reflux events was unaffected by prucalopride, however, the number of reflux events extending to the proximal esophagus was reduced by prucalopride (15.5 [9.8-25.5] vs 10.5 [5.3-17.5], p < 0.05). Furthermore, prucalopride improved acid clearance time (77.5 [47.8-108.8] vs 44.0 [30.0-67.8] s, p < 0.05). Prucalopride did not affect the number of transient lower esophageal sphincter (LES) relaxations or their association with reflux events. Esophageal motility and basal pressure of the LES were not affected by prucalopride. Prucalopride increased gastric emptying (T1/2 ; 32.7 [27.9-44.6] vs 49.8 [37.7-55.0] min, p < 0.05) and decreased residue after 120 min (8.8 [4.4-14.8] vs 2.7 [1.3-5.4] %, p < 0.05). Prucalopride reduces esophageal acid exposure and accelerates gastric emptying in healthy male volunteers. These findings suggest that the drug could be effective for treatment of patients with reflux disease and functional dyspepsia. © 2014 John Wiley & Sons Ltd.

Depletion of Intracellular Thiols and Increased Production of 4-Hydroxynonenal that Occur During Cryopreservation of Stallion Spermatozoa Lead to Caspase Activation, Loss of Motility, and Cell Death.

PubMed

Martin Muñoz, Patricia; Ortega Ferrusola, Cristina; Vizuete, Guillermo; Plaza Dávila, Maria; Rodriguez Martinez, Heriberto; Peña, Fernando J

2015-12-01

Oxidative stress has been linked to sperm death and the accelerated senescence of cryopreserved spermatozoa. However, the molecular mechanisms behind this phenomenon remain poorly understood. Reactive oxygen species (ROS) are considered relevant signaling molecules for sperm function, only becoming detrimental when ROS homeostasis is lost. We hereby hypothesize that a major component of the alteration of ROS homeostasis in cryopreserved spermatozoa is the exhaustion of intrinsic antioxidant defense mechanisms. To test this hypothesis, semen from seven stallions was frozen using a standard technique. The parameters of sperm quality (motility, velocity, and membrane integrity) and markers of sperm senescence (caspase 3, 4-hydroxynonenal, and mitochondrial membrane potential) were assessed before and after cryopreservation. Changes in the intracellular thiol content were also monitored. Cryopreservation caused significant increases in senescence markers as well as dramatic depletion of intracellular thiols to less than half of the initial values (P < 0.001) postthaw. Interestingly, very high and positive correlations were observed among thiol levels with sperm functionality postthaw: total motility (r = 0.931, P < 0.001), progressive motility (r = 0.904, P < 0.001), and percentage of live spermatozoa without active caspase 3 (r = 0.996, P < 0.001). In contrast, negative correlations were detected between active caspase 3 and thiol content both in living (r = -0.896) and dead (r = -0.940) spermatozoa; additionally, 4-hydroxynonenal levels were negatively correlated with thiol levels (r = -0.856). In conclusion, sperm functionality postthaw correlates with the maintenance of adequate levels of intracellular thiols. The accelerated senescence of thawed spermatozoa is related to oxidative and electrophilic stress induced by increased production of 4-hydroxynoneal in thawed samples once intracellular thiols are depleted. © 2015 by the Society for the Study of Reproduction, Inc.

A light-regulated type I pilus contributes to Acinetobacter baumannii biofilm, motility and virulence functions.

PubMed

Wood, Cecily R; Ohneck, Emily J; Edelmann, Richard E; Actis, Luis A

2018-06-11

Transcriptional analyses of A. baumannii ATCC 17978 showed that the expression of A1S_2091 was enhanced in cells cultured in darkness at 24°C through a process that depended on the BlsA photoreceptor. Disruption of A1S_2091, a component of the A1S_2088-A1S_2091 polycistronic operon predicted to code for a type I chaperone/usher pilus assembly system, abolished surface motility and pellicle formation but significantly enhanced biofilm formation on plastic by bacteria cultured under darkness. Based on these observations, the A1S_2088-A1S_2091 operon was named the p hoto- r egulated p ilus ABCD ( prpABCD ) operon, with A1S_2091 coding for the PrpA pilin subunit. Unexpectedly, the comparative analyses of ATCC 17978 and prpA isogenic mutant cells cultured at 37°C showed the expression of light-regulated biofilm biogenesis and motility functions under a temperature condition that drastically affects BlsA production and its light sensing activity. These assays also suggest that 17978 cells produce alternative light-regulated adhesins and/or pili systems that enhance bacterial adhesion and biofilm formation both at 24°C and 37°C on plastic as well as on the surface of polarized A549 alveolar epithelial cells, where formation of bacterial filaments and cell chains was significantly enhanced. The inactivation of prpA also resulted in a significant reduction in virulence when tested using the Galleria mellonella virulence model. All these observations provide strong evidence showing the capacity of A. baumannii to sense light and interact with biotic and abiotic surfaces using undetermined alternative sensing and regulatory systems as well as alternative adherence and motility cellular functions that allow this pathogen to persist in different ecological niches. Copyright © 2018 American Society for Microbiology.

The flagellar master operon flhDC is a pleiotropic regulator involved in motility and virulence of the fish pathogen Yersinia ruckeri.

PubMed

Jozwick, A K S; Graf, J; Welch, T J

2017-03-01

To investigate the function of the master flagellar operon flhDC in the fish pathogen Yersinia ruckeri and compare the effect of a constructed flhD mutation to a naturally occurring fliR mutation causing loss-of-motility in emergent biotype 2 (BT2) strains. Yersinia ruckeri flhD and fliR mutants were constructed in a motile strain. Both mutations caused loss-of-motility, ablation of flagellin synthesis and phospholipase secretion, similar to naturally occurring BT2 strains. Transcriptome analysis confirmed flhDC regulation of flagellar, chemotaxis and phospholipase loci as well as other genes of diverse function. The flhD mutation confers a competitive advantage within the fish host when compared with its parent strain, while this advantage was not seen with the naturally occurring fliR mutation. An intact flhD is necessary for expression of the flagellar secretion system as well as other diverse loci, consistent with a role for flhD as a pleiotropic regulator. The maintenance of the flhD locus in Y. ruckeri strains suggests its importance for aspects of Y. ruckeri biology other than virulence, since the flhD mutation conferred a competitive advantage during experimental challenge of rainbow trout. Yersinia ruckeri is the causative agent of enteric red mouth disease, an invasive septicaemia that affects farmed salmonid fish species. Disease outbreaks can cause severe economic losses in aquaculture. BT2 variants, which have independently emerged worldwide, are an increasing threat to farmed fish production. Knowledge of mechanisms involved in virulence, conserved functions and gene regulation among strains may be exploited for the development of novel disease control strategies to prevent pathogen growth or virulence phenotypes within aquaculture. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

21 CFR 876.1725 - Gastrointestinal motility monitoring system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gastrointestinal motility monitoring system. 876... Gastrointestinal motility monitoring system. (a) Identification. A gastrointestinal motility monitoring system is a... esophageal motility monitor and tube, the gastrointestinal motility (electrical) system, and certain...

21 CFR 876.1725 - Gastrointestinal motility monitoring system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gastrointestinal motility monitoring system. 876... Gastrointestinal motility monitoring system. (a) Identification. A gastrointestinal motility monitoring system is a... esophageal motility monitor and tube, the gastrointestinal motility (electrical) system, and certain...

Distinct effects of boar seminal plasma fractions exhibiting different protein profiles on the functionality of highly diluted boar spermatozoa.

PubMed

García, E M; Calvete, J J; Sanz, L; Roca, J; Martínez, E A; Vázquez, J M

2009-04-01

The aim of this study was to evaluate how different protein profiles of seminal plasma (SP) fractions affect sperm functionality in vitro. Ejaculates from three boars were separated into six fractions. The fractions differed from each other in their sperm content, in their total SP protein content, and their spermadhesin PSP-I/PSP-II and heparin-binding protein (HBP) concentrations. Spermatozoa were mainly recovered in fraction 2 (sperm-rich fraction, >1800 x 10(6) spermatozoa/ml), whereas the pre-sperm fraction 1 and the post-sperm fractions 4-6 contained low numbers of spermatozoa (<500 x 10(6)/ml). Except in fraction 2, the total SP protein concentration and the concentration of both, spermadhesin PSP-I/PSP-II and the HBPs increased with fraction order. Distinct time-dependent effects were observed on motility characteristics and membrane integrity of highly diluted boar spermatozoa upon incubation with a 10% dilution of the SP from each fraction. The highest sperm viability was recorded after exposure for 5 h to fraction 2, followed by fractions 1 and 3. The percentages of motile spermatozoa also differed significantly among fractions after 5 h of incubation. Spermatozoa incubated with SP of fractions 1-3 showed the highest percentage motility. We conclude that different SP fractions exert distinct effects on the functionality of highly diluted boar spermatozoa. Fractions 1-3 appear to promote sperm survival, whereas fractions 4-6 seem to be harmful for preserving the physiological functions of highly diluted boar spermatozoa.

Live births from artificial insemination of microfluidic-sorted bovine spermatozoa characterized by trajectories correlated with fertility

PubMed Central

Nagata, Maria Portia B.; Endo, Kenji; Ogata, Kazuko; Yamanaka, Kenichi; Egashira, Junki; Katafuchi, Naoto; Yamanouchi, Tadayuki; Matsuda, Hideo; Goto, Yuki; Sakatani, Miki; Hojo, Takuo; Nishizono, Hirofumi; Yotsushima, Kenji; Takenouchi, Naoki; Hashiyada, Yutaka; Yamashita, Kenichi

2018-01-01

Selection of functional spermatozoa plays a crucial role in assisted reproduction. Passage of spermatozoa through the female reproductive tract requires progressive motility to locate the oocyte. This preferential ability to reach the fertilization site confers fertility advantage to spermatozoa. Current routine sperm selection techniques are inadequate and fail to provide conclusive evidence on the sperm characteristics that may affect fertilization. We therefore developed a selection strategy for functional and progressively motile bovine spermatozoa with high DNA integrity based on the ability to cross laminar flow streamlines in a diffuser-type microfluidic sperm sorter (DMSS). The fluid dynamics, with respect to microchannel geometry and design, are relevant in the propulsion of spermatozoa and, consequently, ultrahigh-throughput sorting. Sorted spermatozoa were assessed for kinematic parameters, acrosome reaction, mitochondrial membrane potential, and DNA integrity. Kinematic and trajectory patterns were used to identify fertility-related subpopulations: the rapid, straighter, progressive, nonsinuous pattern (PN) and the transitional, sinuous pattern (TS). In contrast to the conventional notion that the fertilizing spermatozoon is always vigorously motile and more linear, our results demonstrate that sinuous patterns are associated with fertility and correspond to truly functional spermatozoa as supported by more live births produced from predominant TS than PN subpopulation in the inseminate. Our findings ascertain the true practical application significance of microfluidic sorting of functional sperm characterized by sinuous trajectories that can serve as a behavioral sperm phenotype marker for fertility potential. More broadly, we foresee the clinical application of this sorting technology to assisted reproduction in humans. PMID:29555773

Expression of cyclophilin B is associated with malignant progression and regulation of genes implicated in the pathogenesis of breast cancer.

PubMed

Fang, Feng; Flegler, Ayanna J; Du, Pan; Lin, Simon; Clevenger, Charles V

2009-01-01

Cyclophilin B (CypB) is a 21-kDa protein with peptidyl-prolyl cis-trans isomerase activity that functions as a transcriptional inducer for Stat5 and as a ligand for CD147. To better understand the global function of CypB in breast cancer, T47D cells with a small interfering RNA-mediated knockdown of CypB were generated. Subsequent expression profiling analysis showed that 663 transcripts were regulated by CypB knockdown, and that many of these gene products contributed to cell proliferation, cell motility, and tumorigenesis. Real-time PCR confirmed that STMN3, S100A4, S100A6, c-Myb, estrogen receptor alpha, growth hormone receptor, and progesterone receptor were all down-regulated in si-CypB cells. A linkage analysis of these array data to protein networks resulted in the identification of 27 different protein networks that were impacted by CypB knockdown. Functional assays demonstrated that CypB knockdown also decreased cell growth, proliferation, and motility. Immunohistochemical and immunofluorescent analyses of a matched breast cancer progression tissue microarray that was labeled with an anti-CypB antibody demonstrated a highly significant increase in CypB protein levels as a function of breast cancer progression. Taken together, these results suggest that the enhanced expression of CypB in malignant breast epithelium may contribute to the pathogenesis of this disease through its regulation of the expression of hormone receptors and gene products that are involved in cell proliferation and motility.

Expression of Cyclophilin B is Associated with Malignant Progression and Regulation of Genes Implicated in the Pathogenesis of Breast Cancer

PubMed Central

Fang, Feng; Flegler, Ayanna J.; Du, Pan; Lin, Simon; Clevenger, Charles V.

2009-01-01

Cyclophilin B (CypB) is a 21-kDa protein with peptidyl-prolyl cis-trans isomerase activity that functions as a transcriptional inducer for Stat5 and as a ligand for CD147. To better understand the global function of CypB in breast cancer, T47D cells with a small interfering RNA-mediated knockdown of CypB were generated. Subsequent expression profiling analysis showed that 663 transcripts were regulated by CypB knockdown, and that many of these gene products contributed to cell proliferation, cell motility, and tumorigenesis. Real-time PCR confirmed that STMN3, S100A4, S100A6, c-Myb, estrogen receptor α, growth hormone receptor, and progesterone receptor were all down-regulated in si-CypB cells. A linkage analysis of these array data to protein networks resulted in the identification of 27 different protein networks that were impacted by CypB knockdown. Functional assays demonstrated that CypB knockdown also decreased cell growth, proliferation, and motility. Immunohistochemical and immunofluorescent analyses of a matched breast cancer progression tissue microarray that was labeled with an anti-CypB antibody demonstrated a highly significant increase in CypB protein levels as a function of breast cancer progression. Taken together, these results suggest that the enhanced expression of CypB in malignant breast epithelium may contribute to the pathogenesis of this disease through its regulation of the expression of hormone receptors and gene products that are involved in cell proliferation and motility. PMID:19056847

StarD13 is a tumor suppressor in breast cancer that regulates cell motility and invasion

PubMed Central

HANNA, SAMER; KHALIL, BASSEM; NASRALLAH, ANITA; SAYKALI, BECHARA A.; SOBH, RANIA; NASSER, SELIM; EL-SIBAI, MIRVAT

2014-01-01

Breast cancer is one of the most commonly diagnosed cancers in women around the world. In general, the more aggressive the tumor, the more rapidly it grows and the more likely it metastasizes. Members of the Rho subfamily of small GTP-binding proteins (GTPases) play a central role in breast cancer cell motility and metastasis. The switch between active GTP-bound and inactive GDP-bound state is regulated by guanine nucleotide exchange factors (GEFs), GTPase-activating proteins (GAPs) and guanine-nucleotide dissociation inhibitors (GDIs). We studied the role of StarD13, a recently identified Rho-GAP that specifically inhibits the function of RhoA and Cdc42. We aimed to investigate its role in breast cancer proliferation and metastasis. The levels of expression of this Rho-GAP in tumor tissues of different grades were assayed using immunohistochemistry. We observed that, while the level of StarD13 expression decreases in cancer tissues compared to normal tissues, it increases as the grade of the tumor increased. This was consistent with the fact that although StarD13 was indeed a tumor suppressor in our breast cancer cells, as seen by its effect on cell proliferation, it was needed for cancer cell motility. In fact, StarD13 knockdown resulted in an inhibition of cell motility and cells were not able to detach their tail and move forward. Our study describes, for the first time, a tumor suppressor that plays a positive role in cancer motility. PMID:24627003

Effects of reactive oxygen species on sperm function.

PubMed

Guthrie, H D; Welch, G R

2012-11-01

Reactive oxygen species (ROS) formation and membrane lipid peroxidation have been recognized as problems for sperm survival and fertility. The precise roles and detection of superoxide (SO), hydrogen peroxide (HP), and membrane lipid peroxidation have been problematic, because of the low specificity and sensitivity of the established chemiluminescence assay technologies. We developed flow cytometric assays to measure SO, HP, membrane lipid peroxidation, and inner mitochondrial transmembrane potential in boar sperm. These methods were sufficiently sensitive to permit detection of early changes in ROS formation in sperm cells that were still viable. Basal ROS formation and membrane lipid peroxidation in the absence of ROS generators were low in viable sperm of both fresh and frozen-thawed boar semen, affecting less than 4% of the sperm cells on average. However, this is not the case in other species, as human, bovine, and poultry sperm have large increases in sperm ROS formation, lipid peroxidation, loss of motility, and death in vitro. Closer study of the effects of ROS formation on the relationship between sperm motility and ATP content in boar sperm was conducted using menadione (mitochondrial SO generator) and HP treatment. Menadione or HP caused an immediate disruption of motility with delayed or no decrease in sperm ATP content, respectively. Overall, the inhibitory effects of ROS on motility point to a mitochondrial-independent mechanism. The reduction in motility may have been due to a ROS-induced lesion in ATP utilization or in the contractile apparatus of the flagellum. Published by Elsevier Inc.

Tamoxifen is a potent antioxidant modulator for sperm quality in patients with idiopathic oligoasthenospermia.

PubMed

Guo, Li; Jing, Jun; Feng, Yu-Ming; Yao, Bing

2015-09-01

To explore the new mechanisms of tamoxifen (TAM) in the treatment for patients with idiopathic oligoasthenospermia-antioxidation. In a prospective, randomized, controlled clinical trial, 120 cases of idiopathic oligoasthenospermia were enrolled and randomly assigned to the indomethacin group (n = 60) treated with indomethacin (25 mg, bid) and TAM group (n = 60) treated with TAM (10 mg, bid) for 3 months. Before and after treatment, we evaluated semen parameters, serum malondialdehyde (MDA) and total antioxidant capacity (TAC), seminal plasma MDA and TAC, spermatozoa intracellular reactive oxygen species (ROS), sperm succinate dehydrogenase (SDH) activity, sperm mitochondrial membrane potential (MMP), and sperm adenosine triphosphate (ATP) content. The independent t test and one-way repeated measures analysis of variance were used to compare the variables between and within two groups. In the indomethacin group, the percentage of progressive motile sperms, total motility, sperm MMP, and ATP content were increased significantly after 3-month treatment (P < 0.05). In the TAM group, total sperm count, sperm concentration, the percentage of progressive motile sperms, total motility, serum and seminal plasma TAC, sperm MMP, and ATP content were significantly improved or increased (P < 0.05), while spermatozoa intracellular ROS was significantly decreased (P < 0.05). Compared to the indomethacin group, TAM treatment showed better improvement in total sperm count, sperm concentration, serum TAC, seminal plasma TAC, spermatozoa intracellular ROS, and sperm SDH activity. TAM treatment can significantly improve sperm quality, which is achieved through alleviating oxidative stress, improving sperm mitochondrial functionality, and subsequently increasing sperm motility.

Earthquake-like dynamics in Myxococcus xanthus social motility

PubMed Central

Gibiansky, Maxsim L.; Hu, Wei; Dahmen, Karin A.; Shi, Wenyuan; Wong, Gerard C. L.

2013-01-01

Myxococcus xanthus is a bacterium capable of complex social organization. Its characteristic social (“S”)-motility mechanism is mediated by type IV pili (TFP), linear actuator appendages that propel the bacterium along a surface. TFP are known to bind to secreted exopolysaccharides (EPS), but it is unclear how M. xanthus manages to use the TFP-EPS technology common to many bacteria to achieve its unique coordinated multicellular movements. We examine M. xanthus S-motility, using high-resolution particle-tracking algorithms, and observe aperiodic stick–slip movements. We show that they are not due to chemotaxis, but are instead consistent with a constant TFP-generated force interacting with EPS, which functions both as a glue and as a lubricant. These movements are quantitatively homologous to the dynamics of earthquakes and other crackling noise systems. These systems exhibit critical behavior, which is characterized by a statistical hierarchy of discrete “avalanche” motions described by a power law distribution. The measured critical exponents from M. xanthus are consistent with mean field theoretical models and with other crackling noise systems, and the measured Lyapunov exponent suggests the existence of highly branched EPS. Such molecular architectures, which are common for efficient lubricants but rare in bacterial EPS, may be necessary for S-motility: We show that the TFP of leading “locomotive” cells initiate the collective motion of follower cells, indicating that lubricating EPS may alleviate the force generation requirements on the lead cell and thus make S-motility possible. PMID:23341622

Mitochondrial ATP is required for the maintenance of membrane integrity in stallion spermatozoa, whereas motility requires both glycolysis and oxidative phosphorylation.

PubMed

Davila, M Plaza; Muñoz, P Martin; Bolaños, J M Gallardo; Stout, T A E; Gadella, B M; Tapia, J A; da Silva, C Balao; Ferrusola, C Ortega; Peña, F J

2016-12-01

To investigate the hypothesis that oxidative phosphorylation is a major source of ATP to fuel stallion sperm motility, oxidative phosphorylation was suppressed using the mitochondrial uncouplers CCCP and 2,4,-dinitrophenol (DNP) and by inhibiting mitochondrial respiration at complex IV using sodium cyanide or at the level of ATP synthase using oligomycin-A. As mitochondrial dysfunction may also lead to oxidative stress, production of reactive oxygen species was monitored simultaneously. All inhibitors reduced ATP content, but oligomycin-A did so most profoundly. Oligomycin-A and CCCP also significantly reduced mitochondrial membrane potential. Sperm motility almost completely ceased after the inhibition of mitochondrial respiration and both percentage of motile sperm and sperm velocity were reduced in the presence of mitochondrial uncouplers. Inhibition of ATP synthesis resulted in the loss of sperm membrane integrity and increased the production of reactive oxygen species by degenerating sperm. Inhibition of glycolysis by deoxyglucose led to reduced sperm velocities and reduced ATP content, but not to loss of membrane integrity. These results suggest that, in contrast to many other mammalian species, stallion spermatozoa rely primarily on oxidative phosphorylation to generate the energy required for instance to maintain a functional Na + /K + gradient, which is dependent on an Na + -K + antiporter ATPase, which relates directly to the noted membrane integrity loss. Under aerobic conditions, however, glycolysis also provides the energy required for sperm motility. © 2016 Society for Reproduction and Fertility.

A Novel High Throughput Assay for Anthelmintic Drug Screening and Resistance Diagnosis by Real-Time Monitoring of Parasite Motility

PubMed Central

Smout, Michael J.; Kotze, Andrew C.; McCarthy, James S.; Loukas, Alex

2010-01-01

Background Helminth parasites cause untold morbidity and mortality to billions of people and livestock. Anthelmintic drugs are available but resistance is a problem in livestock parasites, and is a looming threat for human helminths. Testing the efficacy of available anthelmintic drugs and development of new drugs is hindered by the lack of objective high-throughput screening methods. Currently, drug effect is assessed by observing motility or development of parasites using laborious, subjective, low-throughput methods. Methodology/Principal Findings Here we describe a novel application for a real-time cell monitoring device (xCELLigence) that can simply and objectively assess anthelmintic effects by measuring parasite motility in real time in a fully automated high-throughput fashion. We quantitatively assessed motility and determined real time IC50 values of different anthelmintic drugs against several developmental stages of major helminth pathogens of humans and livestock, including larval Haemonchus contortus and Strongyloides ratti, and adult hookworms and blood flukes. The assay enabled quantification of the onset of egg hatching in real time, and the impact of drugs on hatch rate, as well as discriminating between the effects of drugs on motility of drug-susceptible and –resistant isolates of H. contortus. Conclusions/Significance Our findings indicate that this technique will be suitable for discovery and development of new anthelmintic drugs as well as for detection of phenotypic resistance to existing drugs for the majority of helminths and other pathogens where motility is a measure of pathogen viability. The method is also amenable to use for other purposes where motility is assessed, such as gene silencing or antibody-mediated killing. PMID:21103363

Application of Pyridostigmine in Pediatric Gastrointestinal Motility Disorders: A Case Series.

PubMed

Manini, Mhd Louai; Camilleri, Michael; Grothe, Rayna; Di Lorenzo, Carlo

2018-04-01

Gastrointestinal (GI) motility disorders are common in children. Treatment is challenging with limited medical and surgical options. Pyridostigmine, an acetyl cholinesterase inhibitor, increases acetylcholine at the neuromuscular junction promoting intestinal contractions. Little is known about the role and dosing of pyridostigmine in pediatric GI motility disorders. We present a case series of children with GI dysmotility managed with oral pyridostigmine. Patients' diagnoses include chronic intestinal pseudo-obstruction, gastroparesis with delayed small bowel transit, chronic constipation with failure to thrive, and prolonged ileus after pelvic surgery with chronic opioid use. Pyridostigmine was effective and safe in all cases. Pyridostigmine decreased abdominal distention, increased bowel movement frequency, and improved enteral feeding tolerance. Effective dosing ranged between 0.25-2.0 mg/kg/day. One patient experienced cramping abdominal pain while on pyridostigmine, but pain resolved after medication was discontinued. We found oral pyridostigmine to be helpful in children with different GI motility problems. Pyridostigmine should be considered in such patients when other treatment interventions have not been beneficial.

Spirochete motility and morpholgy

NASA Astrophysics Data System (ADS)

Charon, Nyles

2004-03-01

Spirochetes have a unique structure, and as a result their motility is different from that of other bacteria. These organisms can swim in a highly viscous, gel-like medium, such as that found in connective tissue, that inhibits the motility of most other bacteria. In spirochetes, the organelles for motility, the periplasmic flagella, reside inside the cell within the periplasmic space. A given periplasmic flagellum is attached only at one end of the cell, and depending on the species, may or may not overlap in the center of the cell. The number of periplasmic flagella varies from species to species. These structures have been shown to be directly involved in motility and function by rotating within the periplasmic space (1). The present talk focuses on the spirochete that causes Lyme disease, Borrelia burgdorferi. In many bacterial species, cell shape is usually dictated by the peptidoyglycan layer of the cell wall. In the first part of the talk, results will be presented that the morphology of B. burgdorferi is the result of a complex interaction between the cell cylinder and the internal periplasmic flagella resulting in a cell with a flat-wave morphology. Backward moving, propagating waves enable these bacteria to swim and translate in a given direction. Using targeted mutagenesis, we inactivated the gene encoding the major periplasmic flagellar filament protein FlaB. The resulting flaB mutants not only were non-motile, but were rod-shaped (2). Western blot analysis indicated that flaB was no longer synthesized, and electron microscopy revealed that the mutants were completely deficient in periplasmic flagella. Our results indicate that the periplasmic flagella of B. burgdorferi have a skeletal function. These organelles dynamically interact with the rod-shaped cell cylinder to enable the cell to swim, and to confer in part its flat-wave morphology The latter part of the talk concerns the basis for asymmetrical rotation of the periplasmic flagella of B. burgdorferi during chemotaxis. In translational motility, the bundles of periplasmic flagella rotate in opposite directions. When not translating, they rotate in the same direction, and the cells flex. We present evidence that asymmetrical rotation of the bundles during translation does not depend upon the chemotaxis signal transduction system. The histidine kinase CheA is known to be an essential component in the signaling pathway for bacterial chemotaxis. Mutants of cheA in flagellated bacteria continually rotate their flagella in one direction. B. burgdorferi has two copies of cheA. We reasoned that if chemotaxis were essential for asymmetrical rotation of the flagellar bundles, and if the flagellar motors at both cell ends were identical, inactivation of the two cheA genes should result in cells that constant flex. To test this hypothesis, the signaling pathway was completely blocked by construction of a double cheA mutant. This mutant was completely deficient in chemotaxis. Rather than flexing, it failed to reverse, and it continually translated only in one direction. The results indicate that asymmetrical rotation does not depend upon the chemotaxis system but rather upon differences between the two flagellar bundles. We propose that certain factors within the spirochete localize at flagellar motors at one end of the cell to effect this asymmetry (3). References: 1. Charon, N.W. and S.F. Goldstein. 2002. The genetics of motility and chemotaxis of a fascinating group of bacteria: the spirochetes. Ann. Rev. Genetics. 36: 47-73. 2. Motaleb M.A., L. Corum, J.L Bono, A.F. Elias, P. Rosa, D.S. Samuels, N.W. Charon. 2000. Borrelia burgdorferi periplasmic flagella have both skeletal and motility functions. Proc Natl Acad Sci. 2000 97:10899-10904. 3. Li, C. R. Bakker, M. Motaleb, F. Cabello, M.L. Sartakova, and N.W. Charon. 2002. Asymmetrical flagellar rotation in Borrelia burgdorferi non-chemotaxis mutants. Proc. Natl. Acad. Sci. 99:6169-6174.

Protective features of resveratrol on human spermatozoa cryopreservation may be mediated through 5' AMP-activated protein kinase activation.

PubMed

Shabani Nashtaei, M; Amidi, F; Sedighi Gilani, M A; Aleyasin, A; Bakhshalizadeh, Sh; Naji, M; Nekoonam, S

2017-03-01

Biochemical and physical modifications during the freeze-thaw process adversely influence the restoration of energy-dependent sperm functions required for fertilization. Resveratrol, a phytoalexin, has been introduced to activate 5' AMP-activated protein kinase which is a cell energy sensor and a cell metabolism regulator. The cryoprotection of resveratrol on sperm cryoinjury via activation of AMP-activated protein kinase also remains to be elucidated. Our aim, thus, was to investigate: (i) the presence and intracellular localization of AMP-activated protein kinase protein; (ii) whether resveratrol may exert a protective effect on certain functional properties of fresh and post-thaw human spermatozoa through modulation of AMP-activated protein kinase. Spermatozoa from normozoospermic men were incubated with or without different concentrations of Compound C as an AMP-activated protein kinase inhibitor or resveratrol as an AMP-activated protein kinase activator for different lengths of time and were then cryopreserved. AMP-activated protein kinase is expressed essentially in the entire flagellum and the post-equatorial region. Viability of fresh spermatozoa was not significantly affected by the presence of Compound C or resveratrol. However, although Compound C caused a potent inhibition of spermatozoa motility parameters, resveratrol did not induce negative effect, except a significant reduction in motility at 25 μm for 1 h. Furthermore, resveratrol significantly increased AMP-activated protein kinase phosphorylation and mitochondrial membrane potential and decreased reactive oxygen species and apoptosis-like changes in frozen-thawed spermatozoa. Nevertheless, it was not able to compensate decreased sperm viability and motility parameters following cryopreservation. In contrast, Compound C showed opposite effects to resveratrol on AMP-activated protein kinase phosphorylation, reactive oxygen species, apoptosis-like changes, mitochondrial membrane potential, and motility parameters. These findings, although preliminary, suggest that resveratrol-induced improvement of cryopreserved sperm functions may be mediated through activation of AMP-activated protein kinase, indicating the importance of AMP-activated protein kinase activity for human spermatozoa functions. Further investigations are required to elucidate the mechanism by which resveratrol ameliorates oxidative stress-mediated damages in an AMP-activated protein kinase-dependent mechanism. © 2016 American Society of Andrology and European Academy of Andrology.

The Effect of Experimental Hyperthyroidism on Characteristics of Actin-Myosin Interaction in Fast and Slow Skeletal Muscles.

PubMed

Kopylova, G V; Shchepkin, D V; Bershitsky, S Y

2018-05-01

The molecular mechanism of the failure of contractile function of skeletal muscles caused by oxidative damage to myosin in hyperthyroidism is not fully understood. Using an in vitro motility assay, we studied the effect of myosin damage caused by oxidative stress in experimental hyperthyroidism on the actin-myosin interaction and its regulation by calcium. We found that hyperthyroidism-induced oxidation of myosin is accompanied by a decrease in the sliding velocity of the regulated thin filaments in the in vitro motility assay, and this effect is increased with the duration of the pathological process.

[A computer method for the evaluation of Paramecium motor activity using video records of their movement].

PubMed

Bingi, V N; Zarutskiĭ, A A; Kapranov, S V; Kovalev, Iu M; Miliaev, V A; Tereshchenko, N A

2004-01-01

A method for the evaluation of Paramecium caudatum motility was proposed as a tool for the investigation of magnetobiological as well as other physical and chemical effects. The microscopically observed movement of paramecia is recorded and processed using a special software program. The protozoan motility is determined as a function of their mean velocity in a definite time. The main advantages of the method are that it is easily modified for determining various characteristics of the motor activity of paramecia and that the video data obtained can be reused.

An emerging role for p21-activated kinases (Paks) in viral infections.

PubMed

Van den Broeke, Celine; Radu, Maria; Chernoff, Jonathan; Favoreel, Herman W

2010-03-01

p21-activated protein kinases (Paks) are cytosolic serine/threonine protein kinases that act as effectors for small (p21) GTPases of the Cdc42 and Rac families. It has long been established that Paks play a major role in a host of vital cellular functions such as proliferation, survival and motility, and abnormal Pak function is associated with a number of human diseases. Here, we discuss emerging evidence that these enzymes also play a major role in the entry, replication and spread of many important pathogenic human viruses, including HIV. Careful assessment of the potential role of Paks in antiviral immunity will be pivotal to evaluate thoroughly the potential of agents that inhibit Pak as a new class of anti-viral therapeutics.

Non-achalasic motor disorders of the oesophagus.

PubMed

Sifrim, Daniel; Fornari, Fernando

2007-01-01

Motor abnormalities of the oesophagus are characterised by a chronic impairment of the neuromuscular structures that co-ordinate oesophageal function. The best-defined entity is achalasia, which is discussed in a separate chapter. Other motor disorders with clinical relevance include diffuse oesophageal spasm, oesophageal dysmotility associated with scleroderma, and ineffective oesophageal motility. These non-achalasic motor disorders have variable prevalence but they could be associated with invalidating symptoms such as dysphagia, chest pain and gastro-oesophageal reflux disease. New oesophageal diagnostic techniques, including high-resolution manometry, high-frequency intraluminal ultrasound and intraluminal impedance, allow (1) better definition of peristalsis and sphincter function, (2) assessment of changes in oesophageal wall thickness, and (3) evaluation of pressure gradients within the oesophagus and across the sphincters that can produce normal or abnormal patterns of bolus transport. This chapter discusses recent advances in physiology, pathophysiology, diagnosis and treatment of non-achalasic oesophageal motor disorders.

Effect of Chinese Herbal Medicine on Male Infertility.

PubMed

Jiang, Dan; Coscione, Alberto; Li, Lily; Zeng, Bai-Yun

2017-01-01

Male infertility normally refers a male's inability to cause pregnancy in a fertile female partner after 1 year of unprotected intercourse. Male infertility in recent years has been attracting increasing interest from public due to the evidence in decline in semen quality. There are many factors contributing to the male infertility including abnormal spermatogenesis; reproductive tract anomalies or obstruction; inadequate sexual and ejaculatory functions; and impaired sperm motility, imbalance in hormone levels, and immune system dysfunction. Although conventional treatments such as medication, surgical operation, and advanced techniques have helped many male with infertility cause pregnancy in their female partners, effectiveness is not satisfactory and associated with adverse effects. Chinese herbal medicine (CHM) has been used to improve male infertility in China for a very long time and has now been increasingly popular in Western countries for treating infertility. In this chapter we summarized recent development in basic research and clinical studies of CHM in treating male infertility. It has showed that CHM improved sperm motility and quality, increased sperm count and rebalanced inadequate hormone levels, and adjusted immune functions leading to the increased number of fertility. Further, CHM in combination with conventional therapies improved efficacy of conventional treatments. More studies are needed to indentify the new drugs from CHM and ensure safety, efficacy, and consistency of CHM. © 2017 Elsevier Inc. All rights reserved.

Effects of diluting medium and holding time on sperm motility analysis by CASA in ram.

PubMed

Mostafapor, Somayeh; Farrokhi Ardebili, Farhad

2014-01-01

The aim of this study was to evaluate the effects of dilution rate and holding time on various motility parameters using computer-assisted sperm analysis (CASA). The semen samples were collected from three Ghezel rams. Samples were diluted in seminal plasma (SP), phosphate-buffered saline (PBS) containing 1% bovine serum albumin (BSA) and Bioexcell. The motility parameters that computed and recorded by CASA include curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), straightness (STR), linearity (LIN), amplitude of lateral head displacement (ALH), and beat cross frequency (BCF). In all diluters, there was a decrease in the average of all three parameters of sperms movement velocity as the time passed, but density of this decrease was more intensive in SP. The average of ALH between diluters indicated a significant difference, as it was more in Bioexcell in comparison with the similar amount in SP and PBS. The average of LIN in the diluted sperms in Bioexcell was less than two other diluters in all three times. The motility parameters of the diluted sperms in Bioexcell and PBS indicated an important and considerable difference with the diluted sperms in SP. According to the gained results, the Bioexcell has greater ability in preserving motility of sperm in comparison with the other diluters but as SP is considered as physiological environment for sperm. It seems that the evaluation of the motility parameters in Bioexcell and PBS cannot be an accurate and comparable evaluation with SP.