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Sample records for agonist attenuates bone

  1. Mas-related G-protein-coupled receptor c agonist bovine adrenal medulla 8-22 attenuates bone cancer pain in mice

    PubMed Central

    Sun, Yu-E; Lu, Cui-E; Lei, Yishan; Liu, Yue; Ma, Zhengliang; Gu, Xiaoping

    2015-01-01

    Objectives: The aim of this study is to investigate the effects of Mas-related G-protein-coupled receptor C (MrgC) agonist bovine adrenal medulla 8-22 (BAM8-22) on bone cancer pain and mirror-image pain. Methods: Bone cancer pain was induced by intramedullary injection of NC2472 fibrosarcoma cells in the mice. BAM8-22 and/or anti-MrgC antibody were injected intrathecally at day 14 after bone cancer induction and their effects on pain behaviors were detected. The pain behaviours were assessed by the number of spontaneous foot lifts and paw withdrawal mechanical threshold (PWMT) tests. MrgC expression was detected using western blot analysis and immunofluorescence assay. Results: There were increased bone cancer pain and mirror-image pain in the tumor-bearing mice while not in the sham-treated mice. BAM8-22 attenuated bone cancer pain in mice dose dependently with the highest effects at 2 hr after BAM8-22 administration, and anti-MrgC antibody reversed the effects of BAM8-22. However, intrathecal administration of BAM8-22 did not affect the mirror-image pain. Furthermore, BAM8-22 stimulated the expression of MrgC in the spinal dorsal horn. Conclusions: MrgC agonist BAM8-22 could attenuate bone cancer pain in mice. This study may provide a novel strategy for the treatment of bone cancer pain. PMID:26884930

  2. Disease Modification of Breast Cancer–Induced Bone Remodeling by Cannabinoid 2 Receptor Agonists

    PubMed Central

    Symons-Liguori, Ashley M; Largent-Milnes, Tally M; Havelin, Josh J; Ferland, Henry L; Chandramouli, Anupama; Owusu-Ankomah, Mabel; Nikolich-Zugich, Tijana; Bloom, Aaron P; Jimenez-Andrade, Juan Miguel; King, Tamara; Porreca, Frank; Nelson, Mark A; Mantyh, Patrick W; Vanderah, Todd W

    2015-01-01

    Most commonly originating from breast malignancies, metastatic bone cancer causes bone destruction and severe pain. Although novel chemotherapeutic agents have increased life expectancy, patients are experiencing higher incidences of fracture, pain, and drug-induced side effects; furthermore, recent findings suggest that patients are severely undertreated for their cancer pain. Strong analgesics, namely opiates, are first-line therapy in alleviating cancer-related pain despite the severe side effects, including enhanced bone destruction with sustained administration. Bone resorption is primarily treated with bisphosphonates, which are associated with highly undesirable side effects, including nephrotoxicity and osteonecrosis of the jaw. In contrast, cannabinoid receptor 2 (CB2) receptor-specific agonists have been shown to reduce bone loss and stimulate bone formation in a model of osteoporosis. CB2 agonists produce analgesia in both inflammatory and neuropathic pain models. Notably, mixed CB1/CB2 agonists also demonstrate a reduction in ErbB2-driven breast cancer progression. Here we demonstrate for the first time that CB2 agonists reduce breast cancer–induced bone pain, bone loss, and breast cancer proliferation via cytokine/chemokine suppression. Studies used the spontaneously-occurring murine mammary cell line (66.1) implanted into the femur intramedullary space; measurements of spontaneous pain, bone loss, and cancer proliferation were made. The systemic administration of a CB2 agonist, JWH015, for 7 days significantly attenuated bone remodeling, assuaged spontaneous pain, and decreased primary tumor burden. CB2-mediated effects in vivo were reversed by concurrent treatment with a CB2 antagonist/inverse agonist but not with a CB1 antagonist/inverse agonist. In vitro, JWH015 reduced cancer cell proliferation and inflammatory mediators that have been shown to promote pain, bone loss, and proliferation. Taken together, these results suggest CB2 agonists as a

  3. Activation of spinal MrgC-Gi-NR2B-nNOS signaling pathway by Mas oncogene-related gene C receptor agonist bovine adrenal medulla 8-22 attenuates bone cancer pain in mice.

    PubMed

    Sun, Yu'e; Zhang, Juan; Lei, Yishan; Lu, Cui'e; Hou, Bailing; Ma, Zhengliang; Gu, Xiaoping

    2016-01-01

    In the present study, we investigate the effects of Mas oncogene-related gene (Mrg) C receptors (MrgC) on the expression and activation of spinal Gi protein, N-methyl-D-aspartate receptor subunit 2B (NR2B), and neuronal nitric oxide synthase (nNOS) in mouse model of bone cancer pain. The number of spontaneous foot lift (NSF) and paw withdrawal mechanical threshold (PWMT) were measured after inoculation of tumor cells and intrathecal injection of MrgC agonist bovine adrenal medulla 8-22 (BAM8-22) or MrgC antagonist anti-MrgC for 14 days after operation. Expression of spinal MrgC, Gi protein, NR2B and nNOS and their phosphorylated forms after inoculation was examined by immunohistochemistry and Western blotting. Double labeling was used to identify the co-localization of NR2B or nNOS with MrgC in spinal cord dorsal horn (SCDH) neurons. The effects of intrathecal injection of BAM8-22 or anti-MrgC on nociceptive behaviors and the corresponding expression of spinal MrgC, Gi protein, NR2B and nNOS were also investigated. The expression of spinal MrgC, Gi protein, NR2B, and nNOS was higher in tumor-bearing mice in comparison to sham mice or normal mice. Intrathecal injection of MrgC agonist BAM8-22 significantly alleviated bone cancer pain, up-regulated MrgC and Gi protein expression, and down-regulated the expression of spinal p-NR2B, t-nNOS and p-nNOS in SCDH on day 14 after operation, whereas administration of anti-MrgC produced the opposite effect. Meanwhile, MrgC-like immunoreactivity (IR) co-localizes with NR2B-IR or nNOS-IR in SCDH neurons. The present study demonstrates that MrgC-activated spinal Gi-NR2B-nNOS signaling pathway plays important roles in the development of bone cancer pain. These findings may provide a novel strategy for the treatment of bone cancer pain.

  4. Activation of spinal MrgC-Gi-NR2B-nNOS signaling pathway by Mas oncogene-related gene C receptor agonist bovine adrenal medulla 8-22 attenuates bone cancer pain in mice

    PubMed Central

    Sun, Yu’e; Zhang, Juan; Lei, Yishan; Lu, Cui’e; Hou, Bailing; Ma, Zhengliang; Gu, Xiaoping

    2016-01-01

    Objectives: In the present study, we investigate the effects of Mas oncogene-related gene (Mrg) C receptors (MrgC) on the expression and activation of spinal Gi protein, N-methyl-D-aspartate receptor subunit 2B (NR2B), and neuronal nitric oxide synthase (nNOS) in mouse model of bone cancer pain. Methods: The number of spontaneous foot lift (NSF) and paw withdrawal mechanical threshold (PWMT) were measured after inoculation of tumor cells and intrathecal injection of MrgC agonist bovine adrenal medulla 8-22 (BAM8-22) or MrgC antagonist anti-MrgC for 14 days after operation. Expression of spinal MrgC, Gi protein, NR2B and nNOS and their phosphorylated forms after inoculation was examined by immunohistochemistry and Western blotting. Double labeling was used to identify the co-localization of NR2B or nNOS with MrgC in spinal cord dorsal horn (SCDH) neurons. The effects of intrathecal injection of BAM8-22 or anti-MrgC on nociceptive behaviors and the corresponding expression of spinal MrgC, Gi protein, NR2B and nNOS were also investigated. Results: The expression of spinal MrgC, Gi protein, NR2B, and nNOS was higher in tumor-bearing mice in comparison to sham mice or normal mice. Intrathecal injection of MrgC agonist BAM8-22 significantly alleviated bone cancer pain, up-regulated MrgC and Gi protein expression, and down-regulated the expression of spinal p-NR2B, t-nNOS and p-nNOS in SCDH on day 14 after operation, whereas administration of anti-MrgC produced the opposite effect. Meanwhile, MrgC-like immunoreactivity (IR) co-localizes with NR2B-IR or nNOS-IR in SCDH neurons. Conclusions: The present study demonstrates that MrgC-activated spinal Gi-NR2B-nNOS signaling pathway plays important roles in the development of bone cancer pain. These findings may provide a novel strategy for the treatment of bone cancer pain. PMID:27158400

  5. Neurotensin agonist attenuates nicotine potentiation to cocaine sensitization.

    PubMed

    Fredrickson, Paul; Boules, Mona; Stennett, Bethany; Richelson, Elliott

    2014-03-01

    Tobacco usage typically precedes illicit drug use in adolescent and young adult populations. Several animal studies suggest nicotine increases the risk for subsequent cocaine abuse, and may be a negative prognostic factor for treatment of cocaine addiction; i.e., a "gateway drug". Neurotensin (NT) is a 13-amino acid neuropeptide that modulates dopamine, acetylcholine, glutamate, and GABA neurotransmission in brain reward pathways. NT69L, a NT(8-13) analog, blocks behavioral sensitization (an animal model for psychostimulant addiction) to nicotine, and nicotine self-administration in rats. The present study tested the effect of NT69L on the potentiating effects of nicotine on cocaine-induced locomotor sensitization. Male Wistar rats were injected daily for seven days with nicotine or saline (control) followed by four daily injections of cocaine. NT69L was administered 30 min prior to the last cocaine injection. Behavior was recorded with the use of activity chambers. Subchronic administration of nicotine enhanced cocaine-induced behavioral sensitization in Wistar rats, consistent with an hypothesized gateway effect. These behavioral effects of cocaine were attenuated by pretreatment with NT69L. The effect of the neurotensin agonist on cocaine sensitization in the nicotine treated group indicated a possible therapeutic effect for cocaine addiction, even in the presence of enhanced behavioral sensitization induced by nicotine.

  6. Ingestion of TRP channel agonists attenuates exercise-induced muscle cramps.

    PubMed

    Craighead, Daniel H; Shank, Sean W; Gottschall, Jinger S; Passe, Dennis H; Murray, Bob; Alexander, Lacy M; Kenney, W Larry

    2017-02-13

    Exercise associated muscle cramping (EAMC) is a poorly understood problem that is neuromuscular in origin. Ingestion of transient receptor potential (TRP) channel agonists has been efficacious in attenuating electrically-induced muscle cramps.

  7. Estrogen receptor agonists for attenuation of neuroinflammation and neurodegeneration

    PubMed Central

    Chakrabarti, Mrinmay; Haque, Azizul; Banik, Naren L.; Nagarkatti, Prakash; Nagarkatti, Mitzi; Ray, Swapan K.

    2014-01-01

    Recent results from laboratory investigations and clinical trials indicate important roles for estrogen receptor (ER) agonists in protecting the central nervous system (CNS) from noxious consequences of neuroinflammation and neurodegeneration. Neurodegenerative processes in several CNS disorders including spinal cord injury (SCI), multiple sclerosis (MS), Parkinson's disease (PD), and Alzheimer's disease (AD) are associated with activation of microglia and astrocytes, which drive the resident neuroinflammatory response. During neurodegenerative processes, activated microglia and astrocytes cause deleterious effects on surrounding neurons. The inhibitory activity of ER agonists on microglia activation might be a beneficial therapeutic option for delaying the onset or progression of neurodegenerative injuries and diseases. Recent studies suggest that ER agonists can provide neuroprotection by modulation of cell survival mechanisms, synaptic reorganization, regenerative responses to axonal injury, and neurogenesis process. The anti-inflammatory and neuroprotective actions of ER agonists are mediated mainly via two ERs known as ERα and ERβ. Although some studies have suggested that ER agonists may be deleterious to some neuronal populations, the potential clinical benefits of ER agonists for augmenting cognitive function may triumph over the associated side effects. Also, understanding the modulatory activities of ER agonists on inflammatory pathways will possibly lead to the development of selective anti-inflammatory molecules with neuroprotective roles in different CNS disorders such as SCI, MS, PD, and AD in humans. Future studies should be concentrated on finding the most plausible molecular pathways for enhancing protective functions of ER agonists in treating neuroinflammatory and neurodegenerative injuries and diseases in the CNS. PMID:25245209

  8. Nicotinic acetylcholine receptor agonist attenuates ILC2-dependent airway hyperreactivity

    PubMed Central

    Galle-Treger, Lauriane; Suzuki, Yuzo; Patel, Nisheel; Sankaranarayanan, Ishwarya; Aron, Jennifer L.; Maazi, Hadi; Chen, Lin; Akbari, Omid

    2016-01-01

    Allergic asthma is a complex and chronic inflammatory disorder that is associated with airway hyperreactivity (AHR) and driven by Th2 cytokine secretion. Type 2 innate lymphoid cells (ILC2s) produce large amounts of Th2 cytokines and contribute to the development of AHR. Here, we show that ILC2s express the α7-nicotinic acetylcholine receptor (α7nAChR), which is thought to have an anti-inflammatory role in several inflammatory diseases. We show that engagement of a specific agonist with α7nAChR on ILC2s reduces ILC2 effector function and represses ILC2-dependent AHR, while decreasing expression of ILC2 key transcription factor GATA-3 and critical inflammatory modulator NF-κB, and reducing phosphorylation of upstream kinase IKKα/β. Additionally, the specific α7nAChR agonist reduces cytokine production and AHR in a humanized ILC2 mouse model. Collectively, our data suggest that α7nAChR expressed by ILC2s is a potential therapeutic target for the treatment of ILC2-mediated asthma. PMID:27752043

  9. A formyl peptide receptor agonist suppresses inflammation and bone damage in arthritis.

    PubMed

    Kao, W; Gu, R; Jia, Y; Wei, Xuemin; Fan, H; Harris, J; Zhang, Zhiyi; Quinn, J; Morand, E F; Yang, Y H

    2014-09-01

    Annexin A1 (AnxA1) is an endogenous anti-inflammatory protein and agonist of the formyl peptide receptor 2 (FPR2). However, the potential for therapeutic FPR ligands to modify immune-mediated disease has been little explored. We investigated the effects of a synthetic FPR agonist on joint disease in the K/BxN model of rheumatoid arthritis (RA) and RA fibroblast-like synoviocytes (FLS). Arthritis was induced by injection of K/BxN serum at day 0 and 2 in wild-type (WT) or AnxA1(-/-) mice and clinical and histopathological manifestations measured 8-11 days later. WT mice were given the FPR agonist compound 43 (Cpd43) (6 or 30 mg·kg(-1) i.p.) for 4 days. Effects of AnxA1 and Cpd43 on RANKL-induced osteoclastogenesis were assessed in RAW 264.7 cells and human RA FLS and macrophages. Treatment with Cpd43 before or after the onset of arthritis reduced clinical disease severity and attenuated synovial TNF-α and osteoclast-associated gene expression. Deletion of AnxA1 in mice exacerbated arthritis severity in the K/BxN model. In vitro, Cpd43 suppressed osteoclastogenesis and NFAT activity elicited by RANKL, and inhibited IL-6 secretion by mouse macrophages. In human RA joint-derived FLS and monocyte-derived macrophages, Cpd43 treatment inhibited IL-6 release, while blocking FPR2 or silencing AnxA1 increased this release. The FPR agonist Cpd43 reduced osteoclastogenesis and inflammation in a mouse model of RA and exhibited anti-inflammatory effects in relevant human cells. These data suggest that FPR ligands may represent novel therapeutic agents capable of ameliorating inflammation and bone damage in RA. © 2014 The British Pharmacological Society.

  10. Mechanisms for attenuation in cancellous-bone-mimicking phantoms.

    PubMed

    Wear, Keith A

    2008-11-01

    Broadband ultrasound attenuation (BUA) in cancellous bone is useful for prediction of osteoporotic fracture risk, but its causes are not well understood. To investigate attenuation mechanisms, 9 cancellous-bone-mimicking phantoms containing nylon filaments (simulating bone trabeculae) embedded within soft-tissue-mimicking fluid (simulating marrow) were interrogated. The measurements of frequency-dependent attenuation coefficient had 3 separable components: 1) a linear (with frequency) component attributable to absorption in the soft-tissue-mimicking fluid, 2) a quasilinear (with frequency) component, which may include absorption in and longitudinal-shear mode conversion by the nylon filaments, and 3) a nonlinear (with frequency) component, which may be attributable to longitudinal-longitudinal scattering by the nylon filaments. The slope of total linear (with frequency) attenuation coefficient (sum of components #1 and #2) versus frequency was found to increase linearly with volume fraction, consistent with reported measurements on cancellous bone. Backscatter coefficient measurements in the 9 phantoms supported the claim that the nonlinear (with frequency) component of attenuation coefficient (component #3) was closely associated with longitudinal-longitudinal scattering. This work represents the first experimental separation of these 3 components of attenuation in cancellous bone-mimicking phantoms.

  11. The beta-agonist isoproterenol attenuates EGF-stimulated wound closure in human airway epithelial cells.

    PubMed

    Schnackenberg, Bradley J; Jones, Stacie M; Pate, Crystal; Shank, Brian; Sessions, Laura; Pittman, Laura M; Cornett, Lawrence E; Kurten, Richard C

    2006-03-01

    Asthma is a disease characterized by reversible airway obstruction. An additional hallmark of chronic asthma is altered wound healing that leads to airway remodeling. Although beta-agonists are effective in treating the bronchospasm associated with asthma, their effects on airway wound healing, which are related to airway remodeling, are unknown. It has been demonstrated that beta-agonists can alter the signaling of epidermal growth factor (EGF) receptors, which are important in timely wound healing. Therefore, we hypothesized that the beta-agonist isoproterenol would affect wound healing. Using an in vitro scrape wound assay, we demonstrated that isoproterenol attenuates EGF-stimulated wound healing in 16HBE airway epithelial cell cultures. Through experiments with forskolin and cells overexpressing beta2-adrenergic receptor-yellow fluorescent protein, we show that attenuation is due to the accumulation of cAMP and the involvement of at least one additional pathway. Furthermore, attenuation is not due to a direct effect on the EGF receptor or to an alteration of the ERK/MAPK signaling cascade. Based on these results, we propose that isoproterenol may exert its effects through other MAPK signaling pathways (JNK and/or p38) or through parallel mechanisms. These results also demonstrate a problem of potential therapeutic relevance in which a commonly prescribed medication may alter wound healing and contribute to the remodeling of asthmatic airways.

  12. Nociceptin/orphanin FQ receptor agonists attenuate L-DOPA-induced dyskinesias.

    PubMed

    Marti, Matteo; Rodi, Donata; Li, Qin; Guerrini, Remo; Fasano, Stefania; Morella, Ilaria; Tozzi, Alessandro; Brambilla, Riccardo; Calabresi, Paolo; Simonato, Michele; Bezard, Erwan; Morari, Michele

    2012-11-14

    In the present study we investigated whether the neuropeptide nociceptin/orphanin FQ (N/OFQ), previously implicated in the pathogenesis of Parkinson's disease, also affects L-DOPA-induced dyskinesia. In striatal slices of naive rodents, N/OFQ (0.1-1 μm) prevented the increase of ERK phosphorylation and the loss of depotentiation of synaptic plasticity induced by the D1 receptor agonist SKF38393 in spiny neurons. In vivo, exogenous N/OFQ (0.03-1 nmol, i.c.v.) or a synthetic N/OFQ receptor agonist given systemically (0.01-1 mg/Kg) attenuated dyskinesias expression in 6-hydroxydopamine hemilesioned rats primed with L-DOPA, without causing primary hypolocomotive effects. Conversely, N/OFQ receptor antagonists worsened dyskinesia expression. In vivo microdialysis revealed that N/OFQ prevented dyskinesias simultaneously with its neurochemical correlates such as the surge of nigral GABA and glutamate, and the reduction of thalamic GABA. Regional microinjections revealed that N/OFQ attenuated dyskinesias more potently and effectively when microinjected in striatum than substantia nigra (SN) reticulata, whereas N/OFQ receptor antagonists were ineffective in striatum but worsened dyskinesias when given in SN. Quantitative autoradiography showed an increase in N/OFQ receptor binding in striatum and a reduction in SN of both unprimed and dyskinetic 6-hydroxydopamine rats, consistent with opposite adaptive changes of N/OFQ transmission. Finally, the N/OFQ receptor synthetic agonist also reduced dyskinesia expression in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated dyskinetic macaques without affecting the global parkinsonian score. We conclude that N/OFQ receptor agonists may represent a novel strategy to counteract L-DOPA-induced dyskinesias. Their action is possibly mediated by upregulated striatal N/OFQ receptors opposing the D1 receptor-mediated overactivation of the striatonigral direct pathway.

  13. The sigma receptor agonist SA4503 both attenuates and enhances the effects of methamphetamine

    PubMed Central

    Rodvelt, Kelli R.; Oelrichs, Clark E.; Blount, Lucas R.; Fan, Kuo-Hsien; Lever, Susan Z.; Lever, John R.; Miller, Dennis K.

    2011-01-01

    Background Methamphetamine’s behavioral effects have been attributed to its interaction with monoamine transporters; however, methamphetamine also has affinity for sigma receptors. Method The present study investigated the effect of the sigma receptor agonist SA 4503 and the sigma receptor antagonists BD-1047 and BD-1063 on methamphetamine-evoked [3H] dopamine release from preloaded rat striatal slices. The effect of SA 4503 on methamphetamine-induced hyperactivity and on the discriminative stimulus properties of methamphetamine also was determined. Results SA 4503 attenuated methamphetamine-evoked [3H]dopamine release in a concentration-dependent manner. BD-1047 and BD-1063 did not affect release. SA 4503 dose-dependently potentiated and attenuated methamphetamine-induced hyperactivity. SA 4503 pretreatment augmented the stimulus properties of methamphetamine. Conclusions Our findings indicate that SA 4503 both enhances and inhibits methamphetamine’s effects and that sigma receptors are involved in the neurochemical, locomotor stimulatory and discriminative stimulus properties of methamphetamine. PMID:21277708

  14. Peroxisome proliferator-activated receptor-γ agonists attenuate biofilm formation by Pseudomonas aeruginosa.

    PubMed

    Bedi, Brahmchetna; Maurice, Nicholas M; Ciavatta, Vincent T; Lynn, K Sabrina; Yuan, Zhihong; Molina, Samuel A; Joo, Myungsoo; Tyor, William R; Goldberg, Joanna B; Koval, Michael; Hart, C Michael; Sadikot, Ruxana T

    2017-08-01

    Pseudomonas aeruginosa is a significant contributor to recalcitrant multidrug-resistant infections, especially in immunocompromised and hospitalized patients. The pathogenic profile of P. aeruginosa is related to its ability to secrete a variety of virulence factors and to promote biofilm formation. Quorum sensing (QS) is a mechanism wherein P. aeruginosa secretes small diffusible molecules, specifically acyl homo serine lactones, such as N-(3-oxo-dodecanoyl)-l-homoserine lactone (3O-C12-HSL), that promote biofilm formation and virulence via interbacterial communication. Strategies that strengthen the host's ability to inhibit bacterial virulence would enhance host defenses and improve the treatment of resistant infections. We have recently shown that peroxisome proliferator-activated receptor γ (PPARγ) agonists are potent immunostimulators that play a pivotal role in host response to virulent P. aeruginosa Here, we show that QS genes in P. aeruginosa (strain PAO1) and 3O-C12-HSL attenuate PPARγ expression in bronchial epithelial cells. PAO1 and 3O-C12-HSL induce barrier derangements in bronchial epithelial cells by lowering the expression of junctional proteins, such as zonula occludens-1, occludin, and claudin-4. Expression of these proteins was restored in cells that were treated with pioglitazone, a PPARγ agonist, before infection with PAO1 and 3O-C12-HSL. Barrier function and bacterial permeation studies that have been performed in primary human epithelial cells showed that PPARγ agonists are able to restore barrier integrity and function that are disrupted by PAO1 and 3O-C12-HSL. Mechanistically, we show that these effects are dependent on the induction of paraoxonase-2, a QS hydrolyzing enzyme, that mitigates the effects of QS molecules. Importantly, our data show that pioglitazone, a PPARγ agonist, significantly inhibits biofilm formation on epithelial cells by a mechanism that is mediated via paraoxonase-2. These findings elucidate a novel role for

  15. Etelcalcetide (AMG 416), a peptide agonist of the calcium-sensing receptor, preserved cortical bone structure and bone strength in subtotal nephrectomized rats with established secondary hyperparathyroidism.

    PubMed

    Li, Xiaodong; Yu, Longchuan; Asuncion, Frank; Grisanti, Mario; Alexander, Shawn; Hensley, Kelly; Han, Chun-Ya; Niu, Qing-Tian; Dwyer, Denise; Villasenor, Kelly; Stolina, Marina; Dean, Charles; Ominsky, Michael S; Ke, Hua Zhu; Tomlinson, James E; Richards, William G

    2017-09-01

    Sustained elevation of parathyroid hormone (PTH) is catabolic to cortical bone, as evidenced by deterioration in bone structure (cortical porosity), and is a major factor for increased fracture risk in chronic kidney disease (CKD). Etelcalcetide (AMG 416), a novel peptide agonist of the calcium-sensing receptor, reduces PTH levels in subtotal nephrectomized (Nx) rats and in hemodialysis patients with secondary hyperparathyroidism (SHPT) in clinical studies; however, effects of etelcalcetide on bone have not been determined. In a rat model of established SHPT with renal osteodystrophy, etelcalcetide or vehicle was administered by subcutaneous (s.c.) injection to subtotal Nx rats with elevated PTH (>750pg/mL) once per day for 6weeks. Sham-operated rats receiving vehicle (s.c.) served as non-SHPT controls. Prior to treatment, significant increases in serum creatinine (2-fold), blood urea nitrogen (BUN, 3-fold), PTH (5-fold), fibroblast growth factor-23 (FGF23; 13-fold) and osteocalcin (12-fold) were observed in SHPT rats compared to non-SHPT controls. Elevations in serum creatinine and BUN were unaffected by treatment with vehicle or etelcalcetide. In contrast, etelcalcetide significantly decreased PTH, FGF23 and osteocalcin, whereas vehicle treatment did not. Cortical bone porosity increased and bone strength decreased in vehicle-treated SHPT rats compared to non-SHPT controls. Cortical bone structure improved and energy to failure was significantly greater in SHPT rats treated with etelcalcetide compared to vehicle. Mineralization lag time and marrow fibrosis were significantly reduced by etelcalcetide. In conclusion, etelcalcetide reduced bone turnover, attenuated mineralization defect and marrow fibrosis, and preserved cortical bone structure and bone strength by lowering PTH in subtotal Nx rats with established SHPT. Copyright © 2017. Published by Elsevier Inc.

  16. The GABAA agonist muscimol attenuates induced airway constriction in guinea pigs in vivo.

    PubMed

    Gleason, Neil R; Gallos, George; Zhang, Yi; Emala, Charles W

    2009-04-01

    GABA(A) channels are ubiquitously expressed on neuronal cells and act via an inward chloride current to hyperpolarize the cell membrane of mature neurons. Expression and function of GABA(A) channels on airway smooth muscle cells has been demonstrated in vitro. Airway smooth muscle cell membrane hyperpolarization contributes to relaxation. We hypothesized that muscimol, a selective GABA(A) agonist, could act on endogenous GABA(A) channels expressed on airway smooth muscle to attenuate induced increases in airway pressures in anesthetized guinea pigs in vivo. In an effort to localize muscimol's effect to GABA(A) channels expressed on airway smooth muscle, we pretreated guinea pigs with a selective GABA(A) antagonist (gabazine) or eliminated lung neural control from central parasympathetic, sympathetic, and nonadrenergic, noncholinergic (NANC) nerves before muscimol treatment. Pretreatment with intravenous muscimol alone attenuated intravenous histamine-, intravenous acetylcholine-, or vagal nerve-stimulated increases in peak pulmonary inflation pressure. Pretreatment with the GABA(A) antagonist gabazine blocked muscimol's effect. After the elimination of neural input to airway tone by central parasympathetic nerves, peripheral sympathetic nerves, and NANC nerves, intravenous muscimol retained its ability to block intravenous acetylcholine-induced increases in peak pulmonary inflation pressures. These findings demonstrate that the GABA(A) agonist muscimol acting specifically via GABA(A) channel activation attenuates airway constriction independently of neural contributions. These findings suggest that therapeutics directed at the airway smooth muscle GABA(A) channel may be a novel therapy for airway constriction following airway irritation and possibly more broadly in diseases such as asthma and chronic obstructive pulmonary disease.

  17. The GABA(B) receptor agonist baclofen attenuates cocaine- and heroin-seeking behavior by rats.

    PubMed

    Di Ciano, Patricia; Everitt, Barry J

    2003-03-01

    Conditioned stimuli paired with drugs of abuse can acquire motivational properties, and are capable of inducing drug-seeking behavior and relapse to cocaine use. Converging evidence implicates the mesolimbic dopamine (DA) system, through interactions with limbic afferents to the nucleus accumbens, in behavior controlled by conditioned stimuli. The GABA(B) receptor agonist baclofen has been shown to decrease break points in rats responding for cocaine under progressive ratio schedules and also to attenuate activation of limbic cortical areas in human cocaine addicts. The purpose of the present study was therefore to investigate the effects of baclofen on drug-associated cue-controlled cocaine- or heroin-seeking behavior by rats. Under the second-order schedule of reinforcement used in the present study, cocaine or heroin were available after a fixed time interval, while high rates of responding during the interdrug intervals were maintained by the response-contingent presentations of drug-associated conditioned reinforcers. Baclofen decreased stimulus-maintained responding for either heroin or cocaine, but decreased only cocaine intake under an FR1 schedule. These results therefore support preliminary clinical findings and suggest that drugs with GABA(B) receptor agonist properties may aid abstinence in human drug addicts by decreasing the propensity to cue-induced drug-seeking and relapse.

  18. Mechanical Loading Attenuates Radiation-Induced Bone Loss in Bone Marrow Transplanted Mice.

    PubMed

    Govey, Peter M; Zhang, Yue; Donahue, Henry J

    2016-01-01

    Exposure of bone to ionizing radiation, as occurs during radiotherapy for some localized malignancies and blood or bone marrow cancers, as well as during space travel, incites dose-dependent bone morbidity and increased fracture risk. Rapid trabecular and endosteal bone loss reflects acutely increased osteoclastic resorption as well as decreased bone formation due to depletion of osteoprogenitors. Because of this dysregulation of bone turnover, bone's capacity to respond to a mechanical loading stimulus in the aftermath of irradiation is unknown. We employed a mouse model of total body irradiation and bone marrow transplantation simulating treatment of hematologic cancers, hypothesizing that compression loading would attenuate bone loss. Furthermore, we hypothesized that loading would upregulate donor cell presence in loaded tibias due to increased engraftment and proliferation. We lethally irradiated 16 female C57Bl/6J mice at age 16 wks with 10.75 Gy, then IV-injected 20 million GFP(+) total bone marrow cells. That same day, we initiated 3 wks compression loading (1200 cycles 5x/wk, 10 N) in the right tibia of 10 of these mice while 6 mice were irradiated, non-mechanically-loaded controls. As anticipated, before-and-after microCT scans demonstrated loss of trabecular bone (-48.2% Tb.BV/TV) and cortical thickness (-8.3%) at 3 wks following irradiation. However, loaded bones lost 31% less Tb.BV/TV and 8% less cortical thickness (both p<0.001). Loaded bones also had significant increases in trabecular thickness and tissue mineral densities from baseline. Mechanical loading did not affect donor cell engraftment. Importantly, these results demonstrate that both cortical and trabecular bone exposed to high-dose therapeutic radiation remain capable of an anabolic response to mechanical loading. These findings inform our management of bone health in cases of radiation exposure.

  19. Estimation of ultrasonic attenuation in a bone using coded excitation.

    PubMed

    Nowicki, A; Litniewski, J; Secomski, W; Lewin, P A; Trots, I

    2003-11-01

    This paper describes a novel approach to estimate broadband ultrasound attenuation (BUA) in a bone structure in human in vivo using coded excitation. BUA is an accepted indicator for assessment of osteoporosis. In the tested approach a coded acoustic signal is emitted and then the received echoes are compressed into brief, high amplitude pulses making use of matched filters and correlation receivers. In this way the acoustic peak pressure amplitude probing the tissue can be markedly decreased whereas the average transmitted intensity increases proportionally to the length of the code. This paper examines the properties of three different transmission schemes, based on Barker code, chirp and Golay code. The system designed is capable of generating 16 bits complementary Golay code (CGC), linear frequency modulated (LFM) chirp and 13-bit Barker code (BC) at 0.5 and 1 MHz center frequencies. Both in vivo data acquired from healthy heel bones and in vitro data obtained from human calcaneus were examined and the comparison between the results using coded excitation and two cycles sine burst is presented. It is shown that CGC system allows the effective range of frequencies employed in the measurement of broadband acoustic energy attenuation in the trabecular bone to be doubled in comparison to the standard 0.5 MHz pulse transmission. The algorithm used to calculate the pairs of Golay sequences of the different length, which provide the temporal side-lobe cancellation is also presented. Current efforts are focused on adapting the system developed for operation in pulse-echo mode; this would allow examination and diagnosis of bones with limited access such as hip bone.

  20. Alcohol-heightened aggression in mice: attenuation by 5-HT1A receptor agonists.

    PubMed

    Miczek, K A; Hussain, S; Faccidomo, S

    1998-09-01

    One of the critical mechanisms by which alcohol heightens aggression involves forebrain serotonin (5-HT) systems, possibly via actions on 5-HT1A receptors. The present experiments tested the hypothesis that activating 5-HT1A receptors by selective agonists will block the aggression-heightening effects of ethanol. Initially, the selective antagonist WAY 100635 was used to assess whether or not the changes in aggressive behavior after treatment with 8-OH-DPAT and flesinoxan result from action at the 5-HT1A receptors. Resident male CFW mice engaged in aggressive behavior (i.e. attack bites, sideways threats, tail rattle) during 5-min confrontations with a group-housed intruder male. Quantitative analysis of the behavioral repertoire revealed systematic reductions in all salient elements of aggressive behavior after treatment with 8-OH-DPAT (0.1-0.3 mg/kg, i.p.) or flesinoxan (0.1-1.0 mg/kg, i.p.). The 5-HT1A agonists also reduced motor activities such as walking, rearing and grooming, although to a lesser degree. Pretreatment with the antagonist WAY 100635 (0.1 mg/kg, i.p.) shifted the agonist dose-effect curves for behavioral effects to the right. In a further experiment, oral ethanol (1.0 g/kg, p.o.) increased the frequency of attacks in excess of 2 SD from their mean vehicle level of attacks in 19 out of 76 resident mice. Low doses of 8-OH-DPAT (0.03-0.3 mg/kg) and flesinoxan (0.1, 0.3, 0.6 mg/kg), given before the ethanol treatment, attenuated the alcohol-heightened aggression in a dose-dependent fashion. By contrast, these low 5-HT1A agonist doses affected motor activity in ethanol-treated resident mice to a lesser degree, suggesting behavioral specificity of these anti-aggressive effects. The current results support the hypothesized significant role of 5-HT1A receptors in the aggression-heightening effects of alcohol. If these effects are in fact due to action at somatodendritic 5-HT1A autoreceptors, then the anti-aggressive effects would be associated with

  1. Mechanical Loading Attenuates Radiation-Induced Bone Loss in Bone Marrow Transplanted Mice

    PubMed Central

    Govey, Peter M.; Zhang, Yue; Donahue, Henry J.

    2016-01-01

    Exposure of bone to ionizing radiation, as occurs during radiotherapy for some localized malignancies and blood or bone marrow cancers, as well as during space travel, incites dose-dependent bone morbidity and increased fracture risk. Rapid trabecular and endosteal bone loss reflects acutely increased osteoclastic resorption as well as decreased bone formation due to depletion of osteoprogenitors. Because of this dysregulation of bone turnover, bone’s capacity to respond to a mechanical loading stimulus in the aftermath of irradiation is unknown. We employed a mouse model of total body irradiation and bone marrow transplantation simulating treatment of hematologic cancers, hypothesizing that compression loading would attenuate bone loss. Furthermore, we hypothesized that loading would upregulate donor cell presence in loaded tibias due to increased engraftment and proliferation. We lethally irradiated 16 female C57Bl/6J mice at age 16 wks with 10.75 Gy, then IV-injected 20 million GFP(+) total bone marrow cells. That same day, we initiated 3 wks compression loading (1200 cycles 5x/wk, 10 N) in the right tibia of 10 of these mice while 6 mice were irradiated, non-mechanically-loaded controls. As anticipated, before-and-after microCT scans demonstrated loss of trabecular bone (-48.2% Tb.BV/TV) and cortical thickness (-8.3%) at 3 wks following irradiation. However, loaded bones lost 31% less Tb.BV/TV and 8% less cortical thickness (both p<0.001). Loaded bones also had significant increases in trabecular thickness and tissue mineral densities from baseline. Mechanical loading did not affect donor cell engraftment. Importantly, these results demonstrate that both cortical and trabecular bone exposed to high-dose therapeutic radiation remain capable of an anabolic response to mechanical loading. These findings inform our management of bone health in cases of radiation exposure. PMID:27936104

  2. SB 206553, a putative 5-HT2C inverse agonist, attenuates methamphetamine-seeking in rats

    PubMed Central

    2012-01-01

    Background Methamphetamine (meth) dependence presents a substantial socioeconomic burden. Despite the need, there is no FDA-approved pharmacotherapy for psychostimulant dependence. We consider 5-HT2C receptors as viable therapeutic targets. We recently revealed that the atypical antidepressant, mirtazapine, attenuates meth-seeking in a rodent model of human substance abuse. Mirtazapine historically has been considered to be an antagonist at 5-HT2C receptors, but more recently shown to exhibit inverse agonism at constitutively active 5-HT2C receptors. To help distinguish the roles for antagonism vs. inverse agonism, here we explored the ability of a more selective 5-HT2C inverse agonist, SB 206553 to attenuate meth-seeking behavior, and compared its effects to those obtained with 5-HT2C antagonists, SDZ Ser 082 and SB 242084. To do so, rats were trained to self-administer meth and tested for seeking-like behavior in cue reactivity sessions consisting of contingently presenting meth-associated cues without meth reinforcement. We also explored motor function to determine the influence of SB 206553 and SDZ Ser 082 on motor activity in the presence and absence of meth. Results Like mirtazapine, pretreatment with SB 206553 (1.0, 5.0, and 10.0 mg/kg), attenuated meth-seeking. In contrast, the antagonists, SDZ Ser 082 (0.1, 0.3, and 1.0 mg/kg) and SB 242084 (3.0 mg/kg) had no effect on cue reactivity (CR). SB 242084 (3.0 mg/kg) failed to attenuate the effects of 5.0 and 10 mg/kg SB 206553 on CR. Motor function was largely unaltered by the 5-HT2C ligands; however, SB 206553, at the highest dose tested (10.0 mg/kg), attenuated meth-induced rearing behavior. Conclusions The lack of effect by 5-HT2C antagonists suggests that meth-seeking and meth-evoked motor activity are independent of endogenous 5-HT acting at 5-HT2C receptors. While SB 206553 dramatically impacted meth-evoked behaviors it is unclear whether the observed effects were 5-HT2C receptor mediated

  3. Bone marker and bone density responses to dopamine agonist therapy in hyperprolactinemic males.

    PubMed

    Di Somma, C; Colao, A; Di Sarno, A; Klain, M; Landi, M L; Facciolli, G; Pivonello, R; Panza, N; Salvatore, M; Lombardi, G

    1998-03-01

    The aim of this prospective study was to evaluate the bone mineral density (BMD) at lumbar spine and femoral neck levels and biochemical parameters of bone turnover in 20 consecutive hyperprolactinemic males before and after an 18-month treatment with different dopamine agonists. Six patients received bromocriptine at a dose of 2.5-10 mg/day; 7 patients received quinagolide at a dose of 0.075-0.3 mg/day; 7 patients received cabergoline at a dose of 0.5-1.5 mg/week. BMD, serum PRL, testosterone, dihydrotestosterone, and osteocalcin (OC), and urinary cross-linked N-telopeptides of type I collagen (Ntx) levels were measured before and every 6 months during treatment. At study entry, BMD values were lower in patients than controls at both lumbar spine (0.82 +/- 0.03 vs. 1.18 +/- 0.01 g/cm2; P < 0.001) and femoral neck (0.85 +/- 0.02 vs. 0.92 +/- 0.02 g/cm2; P < 0.05) levels. Osteopenia or osteoporosis was diagnosed in 16 patients at the lumbar spine and in 6 of them at the femoral neck level. A significant inverse correlation was found between lumbar spine and femoral neck BMD values and both PRL levels and disease duration (P < 0.01). In the 20 patients, serum OC levels were significantly lower (2.1 +/- 0.1 vs. 9.3 +/- 2.4 microg/L; P < 0.01), whereas Ntx levels were significantly higher (157.8 +/- 1.1 vs. 96.4 +/- 7.4 nmol bone collagen equivalent/mmol creatinine; P < 0.001) than control values. A significant inverse correlation was found between serum PRL and OC (P < 0.01), but not Ntx, levels. After 18 months of treatment, serum PRL levels were suppressed, and gonadal function was restored in all 20 patients, as shown by the normalization of serum T (from 2.2 +/- 0.2 to 5.0 +/- 0.2 microg/L) and dihydrotestosterone (0.3 +/- 0.02 vs. 0.5 +/- 0.01 nmol/L) levels, without any significant difference among groups. A progressive significant increase in serum OC levels together with a significant decrease in Ntx levels were observed after 6, 12, and 18 months of treatment

  4. Peroxisome proliferator-activated receptor-gamma agonist rosiglitazone attenuates postincisional pain by regulating macrophage polarization

    SciTech Connect

    Hasegawa-Moriyama, Maiko; Ohnou, Tetsuya; Godai, Kohei; Kurimoto, Tae; Nakama, Mayo; Kanmura, Yuichi

    2012-09-14

    Highlights: Black-Right-Pointing-Pointer Rosiglitazone attenuated postincisional pain. Black-Right-Pointing-Pointer Rosiglitazone alters macrophage polarization to F4/80{sup +}CD206{sup +} M2 macrophages at the incisional sites. Black-Right-Pointing-Pointer Transplantation of rosiglitazone-treated macrophages produced analgesic effects. -- Abstract: Acute inflammation triggered by macrophage infiltration to injured tissue promotes wound repair and may induce pain hypersensitivity. Peroxisome proliferator-activated receptor {gamma} (PPAR){gamma} signaling is known to regulate heterogeneity of macrophages, which are often referred to as classically activated (M1) and alternatively activated (M2) macrophages. M1 macrophages have considerable antimicrobial activity and produce a wide variety of proinflammatory cytokines. In contrast, M2 macrophages are involved in anti-inflammatory and homeostatic functions linked to wound healing and tissue repair. Although it has been suggested that PPAR{gamma} agonists attenuate pain hypersensitivity, the molecular mechanism of macrophage-mediated effects of PPAR{gamma} signaling on pain development has not been explored. In this study, we investigated the link between the phenotype switching of macrophage polarization induced by PPAR{gamma} signaling and the development of acute pain hypersensitivity. Local administration of rosiglitazone significantly ameliorated hypersensitivity to heat and mechanical stimuli, and paw swelling. Consistent with the down-regulation of nuclear factor {kappa}B (NF{kappa}B) phosphorylation by rosiglitazone at the incisional sites, the number of F4/80{sup +}iNOS{sup +} M1 macrophages was decreased whereas numbers of F4/80{sup +}CD206{sup +} M2 macrophages were increased in rosiglitazone-treated incisional sites 24 h after the procedure. In addition, gene induction of anti-inflammatory M2-macrophage-associated markers such as arginase1, FIZZ1 and interleukin (IL)-10 were significantly increased, whereas

  5. Peroxisome proliferator-activated receptor delta agonist attenuates nicotine suppression effect on human mesenchymal stem cell-derived osteogenesis and involves increased expression of heme oxygenase-1.

    PubMed

    Kim, Dong Hyun; Liu, Jiayong; Bhat, Samerna; Benedict, Gregory; Lecka-Czernik, Beata; Peterson, Stephen J; Ebraheim, Nabil A; Heck, Bruce E

    2013-01-01

    Smoking has long been associated with osteoporosis, decreased bone mineral density, increased risk of bone fracture, and increased health costs. Nicotine, the main component of cigarette smoke, has major negative effects on bone metabolism and skeletal remodeling in vivo. Although osteoblasts and osteoblast-like cells have been used extensively to study the impact of nicotine, few studies have been performed on human mesenchymal stem cells (hMSCs). In this context, we examined the impact of nicotine on (a) hMSCs proliferation, (b) osteoblastic differentiation, (c) alkaline phosphatase (ALP) activity, and (d) expression of canonical genes during differentiation of hMSCs. MSCs isolated from human bone marrow were treated with different concentrations (0, 0.1, 1 and 10 μM) of nicotine for 7 days. Nicotine caused a dose-dependent decrease in cell proliferation, decreased heme oxygenase-1 (HO-1) expression (p < 0.05) and attenuated osteogenesis (p < 0.05) in hMSCs (45 % reduction at day 14). In addition, nicotine caused a dose-dependent decrease in alizarin red staining for calcium and staining for ALP. Induction of HO-1 by peroxisome proliferator-activated receptor delta agonist (GW0742) prevented the effect of nicotine. Nicotine caused a dose-dependent reduction in the expression of BMP-2, a well-known marker for bone formation; however, this was prevented by GW0742 treatment. Therefore, induction of HO-1 prevents the deleterious effects of nicotine on osteogenesis in hMSC. This offers insight into both how nicotine affects bone remodeling and a therapeutic approach to prevent fracture and osteoporosis in smokers.

  6. Melatonin attenuates the development of antinociceptive tolerance to delta-, but not to mu-opioid receptor agonist in mice.

    PubMed

    Dai, Xu; Cui, Shi-gang; Li, Shi-rong; Chen, Qiang; Wang, Rui

    2007-08-22

    The effects of melatonin (Mel) on the development of tolerance to antinociceptive actions induced by mu- and delta-opioid receptor agonists were determined in male Kunming mice. In the mouse tail-flick tests, selective mu and delta receptor agonists were repeatedly administered to mice supraspinally (intracerebroventricularly, i.c.v.) in the absence or presence of melatonin. Administration of endomorphin-1 (EM-1, a mu-opioid receptor agonist) or deltorphin I (del I, a delta-opioid receptor agonist) twice daily for 4 days produced antinociceptive tolerance compared with vehicle controls. Co-administration with melatonin prevented the development of tolerance to deltorphin I analgesia, and this effect was dose dependent. However, melatonin did not affect the development of antinociceptive tolerance to endomorphin-1. Additionally, the attenuation of deltorphin I tolerance by melatonin was reduced by chronic treatment with luzindole (luz), a selective antagonist on the MT(2) receptor subtype. Taken together, these data suggest that melatonin interferes with the neural mechanisms involved in the development of tolerance to delta-opioid agonist analgesia via its receptor.

  7. Identification of highly efficacious glucocorticoid receptor agonists with a potential for reduced clinical bone side effects.

    PubMed

    Harcken, Christian; Riether, Doris; Kuzmich, Daniel; Liu, Pingrong; Betageri, Raj; Ralph, Mark; Emmanuel, Michel; Reeves, Jonathan T; Berry, Angela; Souza, Donald; Nelson, Richard M; Kukulka, Alison; Fadra, Tazmeen N; Zuvela-Jelaska, Ljiljana; Dinallo, Roger; Bentzien, Jörg; Nabozny, Gerald H; Thomson, David S

    2014-02-27

    Synthesis and structure-activity relationship (SAR) of a series of nonsteroidal glucocorticoid receptor (GR) agonists are described. These compounds contain "diazaindole" moieties and display different transcriptional regulatory profiles in vitro and are considered "dissociated" between gene transrepression and transactivation. The lead optimization effort described in this article focused in particular on limiting the transactivation of genes which result in bone side effects and these were assessed in vitro in MG-63 osteosarcoma cells, leading to the identification of (R)-18 and (R)-21. These compounds maintained anti-inflammatory activity in vivo in collagen induced arthritis studies in mouse but had reduced effects on bone relevant parameters compared to the widely used synthetic glucocorticoid prednisolone 2 in vivo. To our knowledge, we are the first to report on selective glucocorticoid ligands with reduced bone loss in a preclinical in vivo model.

  8. Evidence for calreticulin attenuation of cardiac hypertrophy induced by pressure overload and soluble agonists.

    PubMed

    Papp, Sylvia; Dziak, Ewa; Kabir, Golam; Backx, Peter; Clement, Sophie; Opas, Michal

    2010-03-01

    While calreticulin has been shown to be critical for cardiac development, its role in cardiac pathology is unclear. Previous studies have shown the detrimental effects on the heart of sustained germline calreticulin overexpression, yet without calreticulin, the heart does not develop normally. Thus, carefully balanced calreticulin levels are required for the heart to develop and to function properly into adulthood. But what happens to calreticulin levels, and how is this regulated, during cardiac hypertrophy, during which the fetal gene program is reactivated, at least partially? Our working hypothesis was that c-Src, a kinase whose activity we previously found to be correlated with calreticulin expression, was involved with calreticulin in regulating the response to hypertrophic signals. Thus, we subjected adult mice to transverse aortic constriction to induce left ventricular hypertrophy. We found that aortic constriction caused calreticulin levels to increase, whereas those of c-Src fell with longer constriction time. We also examined the ability of embryonic stem cell-derived cardiomyocytes to respond to soluble hypertrophic agonists. Endothelin-1 treatment caused a significantly greater cell area increase of calreticulin-null cardiomyocytes, which had higher c-Src activity, compared with wild-type cells. c-Src inhibition abolished this difference. Greater c-Src activity may explain the efficacy with which calreticulin-null cells are able to induce the hypertrophic program, while cells containing calreticulin may be able to attenuate the hypertrophic response as a result of decreased c-Src activity. Thus, calreticulin may have a protective effect on the heart in the face of cardiac hypertrophy.

  9. PPAR-gamma agonist attenuates renal interstitial fibrosis and inflammation through reduction of TGF-beta.

    PubMed

    Kawai, Toru; Masaki, Takao; Doi, Shigehiro; Arakawa, Tetsuji; Yokoyama, Yukio; Doi, Toshiki; Kohno, Nobuoki; Yorioka, Noriaki

    2009-01-01

    Thiazolidinediones (TZDs), synthetic peroxisome proliferator-activated receptor (PPAR)-gamma ligands, have a central role in insulin sensitization and adipogenesis. It has been reported that TZDs exert protective effects in both diabetic and nondiabetic models of renal disease, although the exact mechanism is not well understood. In particular, only a few studies have reported the renoprotective effects of TZDs in nondiabetic models of tubulointerstitial fibrosis and inflammation. Therefore, we investigated the anti-fibrotic and anti-inflammatory effects of the TZD troglitazone in the mouse model of unilateral ureteral obstruction (UUO). C57BL/6J mice underwent UUO and were studied after 3 and 7 days. Animals were divided into three groups and received control vehicle, troglitazone (150 mg/kg per day) or troglitazone (300 mg/kg per day) by gavage. Kidneys were harvested for morphological, mRNA and protein analysis. Reverse-transcriptase-PCR was used to assess the expression of transforming growth factor-beta1 (TGF-beta1) and the TGF-beta1 type I receptor (TGF beta R-I). Protein expression was assessed by western blotting (TGF beta R-I) and immunostaining (TGF beta R-I, alpha-smooth muscle actin (alpha-SMA), type I collagen (collagen I), F4/80, and proliferating cell nuclear antigen (PCNA)). The expression of alpha-SMA, collagen I, and F4/80 was decreased in mice treated with troglitazone compared with the control group. The numbers of PCNA-positive interstitial cells were decreased in mice treated with troglitazone. TGF-beta1 mRNA and TGF beta R-I mRNA and protein expression were decreased in the group treated with troglitazone compared with the control group. The beneficial effects of troglitazone treatment were also dose dependent. PPAR-gamma agonist significantly reduced TGF-beta and attenuated renal interstitial fibrosis and inflammation in the model of UUO.

  10. Evidence for Calreticulin Attenuation of Cardiac Hypertrophy Induced by Pressure Overload and Soluble Agonists

    PubMed Central

    Papp, Sylvia; Dziak, Ewa; Kabir, Golam; Backx, Peter; Clement, Sophie; Opas, Michal

    2010-01-01

    While calreticulin has been shown to be critical for cardiac development, its role in cardiac pathology is unclear. Previous studies have shown the detrimental effects on the heart of sustained germline calreticulin overexpression, yet without calreticulin, the heart does not develop normally. Thus, carefully balanced calreticulin levels are required for the heart to develop and to function properly into adulthood. But what happens to calreticulin levels, and how is this regulated, during cardiac hypertrophy, during which the fetal gene program is reactivated, at least partially? Our working hypothesis was that c-Src, a kinase whose activity we previously found to be correlated with calreticulin expression, was involved with calreticulin in regulating the response to hypertrophic signals. Thus, we subjected adult mice to transverse aortic constriction to induce left ventricular hypertrophy. We found that aortic constriction caused calreticulin levels to increase, whereas those of c-Src fell with longer constriction time. We also examined the ability of embryonic stem cell-derived cardiomyocytes to respond to soluble hypertrophic agonists. Endothelin-1 treatment caused a significantly greater cell area increase of calreticulin-null cardiomyocytes, which had higher c-Src activity, compared with wild-type cells. c-Src inhibition abolished this difference. Greater c-Src activity may explain the efficacy with which calreticulin-null cells are able to induce the hypertrophic program, while cells containing calreticulin may be able to attenuate the hypertrophic response as a result of decreased c-Src activity. Thus, calreticulin may have a protective effect on the heart in the face of cardiac hypertrophy. PMID:20110410

  11. Inhibitory Effects of Dopamine Receptor D1 Agonist on Mammary Tumor and Bone Metastasis

    PubMed Central

    Minami, Kazumasa; Liu, Shengzhi; Liu, Yang; Chen, Andy; Wan, Qiaoqiao; Na, Sungsoo; Li, Bai-Yan; Matsuura, Nariaki; Koizumi, Masahiko; Yin, Yukun; Gan, Liangying; Xu, Aihua; Li, Jiliang; Nakshatri, Harikrishna; Yokota, Hiroki

    2017-01-01

    Dopaminergic signaling plays a critical role in the nervous system, but little is known about its potential role in breast cancer and bone metabolism. A screening of ~1,000 biologically active compounds revealed that a selective agonist of dopamine receptor D1 (DRD1), A77636, inhibited proliferation of 4T1.2 mammary tumor cells as well as MDA-MB-231 breast cancer cells. Herein, we examined the effect of A77636 on bone quality using a mouse model of bone metastasis from mammary tumor. A77636 inhibited migration of cancer cells in a DRD1-dependent fashion and suppressed development of bone-resorbing osteoclasts by downregulating NFATc1 through the elevation of phosphorylation of eIF2α. In the mouse model of bone metastasis, A77636 reduced osteolytic lesions and prevented mechanical weakening of the femur and tibia. Collectively, we expect that dopaminergic signaling might provide a novel therapeutic target for breast cancer and bone metastasis. PMID:28374823

  12. GLP-1 Receptor Agonist Treatment Increases Bone Formation and Prevents Bone Loss in Weight-Reduced Obese Women.

    PubMed

    Iepsen, Eva W; Lundgren, Julie R; Hartmann, Bolette; Pedersen, Oluf; Hansen, Torben; Jørgensen, Niklas R; Jensen, Jens-Erik B; Holst, Jens J; Madsbad, Sten; Torekov, Signe S

    2015-08-01

    Recent studies indicate that glucagon-like peptide (GLP)-1 regulates bone turnover, but the effects of GLP-1 receptor agonists (GLP-1 RAs) on bone in obese weight-reduced individuals are unknown. To investigate the role of GLP-1 RAs on bone formation and weight loss-induced bone mass reduction. Randomized control study. Outpatient research hospital clinic. Thirty-seven healthy obese women with body mass index of 34 ± 0.5 kg/m(2) and age 46 ± 2 years. After a low-calorie-diet-induced 12% weight loss, participants were randomized to treatment with or without administration of the GLP-1 RA liraglutide (1.2 mg/d) for 52 weeks. In case of weight gain, up to two meals per day could be replaced with a low-calorie-diet product to maintain the weight loss. Total, pelvic, and arm-leg bone mineral content (BMC) and bone markers [C-terminal telopeptide of type 1 collagen (CTX-1) and N-terminal propeptide of type 1 procollagen (P1NP)] were investigated before and after weight loss and after 52-week weight maintenance. Primary endpoints were changes in BMC and bone markers after 52-week weight maintenance with or without GLP-1 RA treatment. Total, pelvic, and arm-leg BMC decreased during weight maintenance in the control group (P < .0001), but not significantly in the liraglutide group. Thus, total and arm-leg BMC loss was four times greater in the control group compared to the liraglutide group (estimated difference, 27 g; 95% confidence interval, 5-48; P = .01), although the 12% weight loss was maintained in both groups. In the liraglutide group, the bone formation marker P1NP increased by 16% (7 ± 3 μg/L) vs a 2% (-1 ± 4 μg/L) decrease in the control group (P < .05). The bone resorption marker CTX-1 collagen did not change during the weight loss maintenance phase. Treatment with a long-acting GLP-1 RA increased bone formation by 16% and prevented bone loss after weight loss obtained through a low-calorie diet, supporting its role as a safe weight-lowering agent.

  13. Peroxisome proliferator activated receptor alpha/gamma dual agonist tesaglitazar attenuates diabetic nephropathy in db/db mice.

    PubMed

    Cha, Dae Ryong; Zhang, Xiaoyan; Zhang, Yahua; Wu, Jing; Su, Dongming; Han, Jee Young; Fang, Xuefen; Yu, Bo; Breyer, Matthew D; Guan, Youfei

    2007-08-01

    Peroxisome proliferator-activated receptors (PPARs) are nuclear transcription factors and play a central role in insulin sensitivity, lipid metabolism, and inflammation. Both PPARalpha and -gamma are expressed in the kidney, and their agonists exhibit renoprotective effects in type 2 diabetes. In the present studies, we investigated the effect of the PPARalpha/gamma dual agonist tesaglitazar on diabetic nephropathy in type 2 diabetic db/db mice. Treatment of db/db mice with tesaglitazar for 3 months significantly lowered fasting plasma glucose and homeostasis model assessment of insulin resistance levels but had little effect on body weight, adiposity, or cardiac function. Treatment with tesaglitazar was associated with reduced plasma insulin and total triglyceride levels and increased plasma adiponectin levels. Notably, tesaglitazar markedly attenuated albuminuria and significantly lowered glomerulofibrosis, collagen deposition, and transforming growth factor-beta1 expression in renal tissues of db/db mice. In cultured mesangial cells and proximal tubule cells, where both PPARalpha and -gamma were expressed, tesaglitazar treatment abolished high glucose-induced total collagen protein production and type I and IV collagen gene expression. Collectively, tesaglitazar treatment not only improved insulin resistance, glycemic control, and lipid profile but also markedly attenuated albuminuria and renal glomerular fibrosis in db/db mice. These findings support the utility of dual PPARalpha/gamma agonists in treating type 2 diabetes and diabetic nephropathy.

  14. Bone loss in men with prostate cancer treated with gonadotropin-releasing hormone agonists.

    PubMed

    Stoch, S A; Parker, R A; Chen, L; Bubley, G; Ko, Y J; Vincelette, A; Greenspan, S L

    2001-06-01

    Prostate cancer is the most common visceral malignancy in men. As the tumor is testosterone dependent, a frequent treatment modality involves therapy with GnRH agonists (GnRH-a) resulting in hypogonadism. Because testosterone is essential for the maintenance of bone mass in men, we postulated that GnRH-a therapy would negatively impact skeletal integrity. We compared bone mineral density (BMD), biochemical markers of bone turnover, and body composition in 60 men with prostate cancer (19 men receiving GnRH-a therapy and 41 eugonadal men) and BMD in 197 community-living healthy controls of similar age. BMD was assessed by dual energy x-ray absorptiometry and ultrasound. Biochemical markers of bone turnover, included markers of bone resorption (urinary N-telopeptide) and bone formation markers (bone-specific alkaline phosphatase and osteocalcin). Body composition (total body fat and lean body mass) was assessed by dual energy x-ray absorptiometry. Significantly lower BMD was found at the lateral spine (0.69 +/- 0.17 vs. 0.83 +/- 0.20 g/cm(2); P < 0.01), total hip (0.94 +/- 0.14 vs. 1.05 +/- 0.16 g/cm(2); P < 0.05), and forearm (0.67 +/- 0.11 vs. 0.78 +/- 0.07 g/cm(2); P < 0.01) in men receiving GnRH-a compared with the eugonadal men with prostate cancer. Significant differences were also seen at the total body, finger, and calcaneus (all P < 0.01). BMD values in eugonadal men with prostate cancer and healthy controls were similar. Markers of bone resorption (urinary N-telopeptide) and bone formation (bone-specific alkaline phosphatase) were elevated in men receiving GnRH-a therapy compared with those in eugonadal men with prostate cancer. Men receiving GnRH-a also had a higher percent total body fat (29 +/- 5% vs. 25 +/- 5%; P < 0.01) and lower percent lean body weight (71 +/- 5% vs. 75 +/- 5%; P < 0.01) compared with eugonadal men with prostate cancer. In conclusion, men with prostate cancer receiving androgen deprivation therapy have a significant decrease in bone

  15. Spinal administration of a delta opioid receptor agonist attenuates hyperalgesia and allodynia in a rat model of neuropathic pain.

    PubMed

    Holdridge, Sarah V; Cahill, Catherine M

    2007-08-01

    Neuropathic (NP) pain is a debilitating chronic pain disorder considered by some to be inherently resistant to therapy with traditional analgesics. Indeed, micro opioid receptor (OR) agonists show reduced therapeutic benefit and their long term use is hindered by the high incidence of adverse effects. However, pharmacological and physiological evidence increasingly suggests a role for deltaOR agonists in modulating NP pain symptoms. In this study, we examined the antihyperalgesic and antiallodynic effects of the spinally administered deltaOR agonist, d-[Ala(2), Glu(4)]deltorphin II (deltorphin II), as well as the changes in deltaOR expression, in rats following chronic constriction injury (CCI) of the sciatic nerve. Rats with CCI exhibited cold hyperalgesia and mechanical allodynia over a 14-day testing period. Intrathecal administration of deltorphin II reversed cold hyperalgesia on day 14 and dose-dependently attenuated mechanical allodynia. The effects of deltorphin II were mediated via activation of the deltaOR as the effect was antagonized by co-treatment with the delta-selective antagonist, naltrindole. Western blotting experiments revealed no changes in deltaOR protein in the dorsal spinal cord following CCI. Taken together, these data demonstrate the antihyperalgesic and antiallodynic effectiveness of a spinally administered deltaOR agonist following peripheral nerve injury and support further investigation of deltaORs as potential therapeutic targets in the treatment of NP pain.

  16. Measurement of the dispersion and attenuation of cylindrical ultrasonic guided waves in long bone.

    PubMed

    Ta, Dean; Wang, Weiqi; Wang, YuanYuan; Le, Lawrence H; Zhou, Yuqing

    2009-04-01

    Osteoporotic bones are likely to have less cortical bone than healthy bones. The velocities of guided waves propagating in a long cylindrical bone are very sensitive to bone properties and cortical thickness (CTh). This work studies the dispersion and attenuation of ultrasonic guided waves propagating in long cylindrical bone. A hollow cylinder filled with a viscous liquid was used to model the long bone and then to calculate the theoretical phase and group velocities, as well as the attenuation of the waves. The generation and selection of guided wave modes were based on theoretical dispersive curves. The phase velocity and attenuation of cylindrical guided wave modes, such as L(0,1), L(0,2) and L(0,3), were measured in bovine tibia using angled beam transducers at various propagation distances ranging from 75 to 160 mm. The results showed that the phase velocity of the L(0,2) guided wave mode decreased with an increase in CTh. The attenuation of the low cylindrical guided wave modes was a nonlinear function that increased with propagation distance and mode order. The L(0,2) mode had a different attenuation for each CTh. The experimental results were in good agreement with the predicted values. Cylindrical guided waves of low-frequency and low-order have been shown to demonstrate more dispersion and less attenuation and should, therefore, be used to evaluate long bone.

  17. Adenosine A(3) receptor agonist acts as a homeostatic regulator of bone marrow hematopoiesis.

    PubMed

    Hofer, Michal; Pospísil, Milan; Znojil, Vladimír; Holá, Jirina; Vacek, Antonín; Streitová, Denisa

    2007-07-01

    The present study was performed to define the optimum conditions of the stimulatory action of the adenosine A(3) receptor agonist, N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA), on bone marrow hematopoiesis in mice. Effects of 2-day treatment with IB-MECA given at single doses of 200nmol/kg twice daily were investigated in normal mice and in mice whose femoral bone marrow cells were either depleted or regenerating after pretreatment with the cytotoxic drug 5-fluorouracil. Morphological criteria were used to determine the proliferation state of the granulocytic and erythroid cell systems. Significant negative correlation between the control proliferation state and the increase of cell proliferation after IB-MECA treatment irrespective of the cell lineage investigated was found. The results suggest the homeostatic character of the induced stimulatory effects and the need to respect the functional state of the target tissue when investigating effects of adenosine receptor agonists under in vivo conditions.

  18. Alpha-7 nicotinic acetylcholine receptor agonist treatment reduces neuroinflammation, oxidative stress, and brain injury in mice with ischemic stroke and bone fracture.

    PubMed

    Han, Zhenying; Li, Li; Wang, Liang; Degos, Vincent; Maze, Mervyn; Su, Hua

    2014-11-01

    Bone fracture at the acute stage of stroke exacerbates stroke injury by increasing neuroinflammation. We hypothesize that activation of α-7 nicotinic acetylcholine receptor (α-7 nAchR) attenuates neuroinflammation and oxidative stress, and reduces brain injury in mice with bone fracture and stroke. Permanent middle cerebral artery occlusion (pMCAO) was performed in C57BL/6J mice followed by tibia fracture 1 day later. Mice were treated with 0.8 mg/kg PHA 568487 (PHA, α-7 nAchR-specific agonist), 6 mg/kg methyllycaconitine (α-7 nAchR antagonist), or saline 1 and 2 days after pMCAO. Behavior was tested 3 days after pMCAO. Neuronal injury, CD68(+) , M1 (pro-inflammatory) and M2 (anti-inflammatory) microglia/macrophages, phosphorylated p65 component of nuclear factor kappa b in microglia/macrophages, oxidative and anti-oxidant gene expression were quantified. Compared to saline-treated mice, PHA-treated mice performed better in behavioral tests, had fewer apoptotic neurons (NeuN(+) TUNEL(+) ), fewer CD68(+) and M1 macrophages, and more M2 macrophages. PHA increased anti-oxidant gene expression and decreased oxidative stress and phosphorylation of nuclear factor kappa b p65. Methyllycaconitine had the opposite effects. Our data indicate that α-7 nAchR agonist treatment reduces neuroinflammation and oxidative stress, which are associated with reduced brain injury in mice with ischemic stroke plus tibia fracture. Bone fracture at the acute stage of stroke exacerbates neuroinflammation, oxidative stress, and brain injury, and our study has shown that the α-7 nAchR agonist, PHA (PHA 568487), attenuates neuroinflammation, oxidative stress, and brain injury in mice with stroke and bone fracture. Hence, PHA could provide an opportunity to develop a new strategy to reduce brain injury in patients suffering from stroke and bone fracture. © 2014 International Society for Neurochemistry.

  19. The trace amine associated receptor 1 agonist RO5263397 attenuates the induction of cocaine behavioral sensitization in rats.

    PubMed

    Thorn, David A; Zhang, Chaogui; Zhang, Yanan; Li, Jun-Xu

    2014-04-30

    The trace amine associated receptor (TAAR) 1 is a new G protein coupled receptor that critically modulates central dopaminergic system. Recently, several selective TAAR 1 ligands have been described to possess antipsychotic and antidepressant-like activities. However, it is unknown of the role of these ligands in modulating psychostimulant-induced neurobehavioral plasticity. This study examined the effects of a selective TAAR 1 agonist, RO5263397, on cocaine induced behavioral sensitization in rats, a rodent model of drug-induced behavioral plasticity. Daily treatment with 15mg/kg cocaine (i.p., 7 days) induced robust locomotor sensitization in rats. RO5263397 (1-10mg/kg, i.p.) alone did not significantly alter the locomotor activity. Acute treatment with RO5263397 (3.2 and 10mg/kg) did not significantly modify cocaine-induced hyperactivity; however, the induction of locomotor sensitization was significantly blocked after 7 days of daily RO5263397 treatment. More importantly, the expression of locomotor sensitization remained significantly attenuated when rats were re-tested 7 days after the last drug treatment. The marked attenuation of cocaine sensitization was also evidenced by the suppression of the dose-effect function (3.2-32mg/kg) of cocaine sensitization. Together, these data represent the first to report a critical modulatory role of TAAR 1 agonists in cocaine-induced behavioral plasticity, which may be indicative of its potential role for altering other long-lasting behavioral maladaptations of cocaine including drug addiction.

  20. Discovery of a CXCR4 agonist pepducin that mobilizes bone marrow hematopoietic cells.

    PubMed

    Tchernychev, Boris; Ren, Yong; Sachdev, Pallavi; Janz, Jay M; Haggis, Lynn; O'Shea, Adam; McBride, Ed; Looby, Richard; Deng, Qing; McMurry, Thomas; Kazmi, Manija A; Sakmar, Thomas P; Hunt, Stephen; Carlson, Kenneth E

    2010-12-21

    The G protein-coupled receptor (GPCR), chemokine CXC-type receptor 4 (CXCR4), and its ligand, CXCL12, mediate the retention of polymorphonuclear neutrophils (PMNs) and hematopoietic stem and progenitor cells (HSPCs) in the bone marrow. Agents that disrupt CXCL12-mediated chemoattraction of CXCR4-expressing cells mobilize PMNs and HSPCs into the peripheral circulation and are therapeutically useful for HSPC collection before autologous bone marrow transplantation (ABMT). Our aim was to develop unique CXCR4-targeted therapeutics using lipopeptide GPCR modulators called pepducins. A pepducin is a synthetic molecule composed of a peptide derived from the amino acid sequence of one of the intracellular (IC) loops of a target GPCR coupled to a lipid tether. We prepared and screened a small CXCR4-targeted pepducin library and identified several pepducins with in vitro agonist activity, including ATI-2341, whose peptide sequence derives from the first IC loop. ATI-2341 induced CXCR4- and G protein-dependent signaling, receptor internalization, and chemotaxis in CXCR4-expressing cells. It also induced dose-dependent peritoneal recruitment of PMNs when administered i.p. to mice. However, when administered systemically by i.v. bolus, ATI-2341 acted as a functional antagonist and dose-dependently mediated release of PMNs from the bone marrow of both mice and cynomolgus monkeys. ATI-2341-mediated release of granulocyte/macrophage progenitor cells from the bone marrow was confirmed by colony-forming assays. We conclude that ATI-2341 is a potent and efficacious mobilizer of bone marrow PMNs and HSPCs and could represent a previously undescribed therapeutic approach for the recruitment of HSPCs before ABMT.

  1. Ultrasonic attenuation in parallel-nylon-wire cancellous-bone-mimicking phantoms.

    PubMed

    Wear, Keith A

    2008-12-01

    Attenuation coefficients between 1.5 and 3.5 MHz were measured on four parallel-nylon-wire arrays (simulating cancellous bone) with four different wire diameters (150, 200, 250, and 300 microm). Interwire spacing was 800 microm for all four parallel-nylon-wire arrays. The measured frequency dependencies of attenuation were consistent with theoretical predications based on Faran's theory, which considers the component of attenuation due to scattering of longitudinal waves.

  2. A novel natural Nrf2 activator with PPARγ-agonist (monascin) attenuates the toxicity of methylglyoxal and hyperglycemia

    SciTech Connect

    Hsu, Wei-Hsuan; Lee, Bao-Hong; Chang, Yu-Ying; Hsu, Ya-Wen; Pan, Tzu-Ming

    2013-11-01

    Methylglyoxal (MG) is a toxic-glucose metabolite and a major precursor of advanced glycation endproducts (AGEs). MG has been reported to result in inflammation by activating receptor for AGEs (RAGE). We recently found that Monascus-fermented metabolite monascin acts as a novel natural peroxisome proliferator-activated receptor-γ (PPARγ) agonist that improves insulin sensitivity. We investigated the metabolic, biochemical, and molecular abnormalities characteristic of type 2 diabetes in MG-treated Wistar rats treated with oral administration of monascin or rosiglitazone. Monascin (a novel PPARγ agonist) activated nuclear factor-erythroid 2-related factor 2 (Nrf2) and down-regulated hyperinsulinmia in oral glucose tolerance test (OGTT). Monascin was able to elevate glyoxalase-1 expression via activation of hepatic Nrf2, hence, resulting in MG metabolism to D-lactic acid and protected from AGEs production in MG-treated rats. Rosiglitazone did not activate Nrf2 nor glyoxalase expression to lower serum and hepatic AGEs levels. Monascin acts as a novel natural Nrf2 activator with PPARγ-agonist activity were confirmed by Nrf2 and PPARγ reporter assays in Hep G2 cells. These findings suggest that monascin acts as an anti-diabetic and anti-oxidative stress agent to a greater degree than rosiglitazone and thus may have therapeutic potential for the prevention of diabetes. - Highlights: • Monascin acts as a PPARgamma agonist. • Monascin activates Nrf2 and AMPK. • Monascin promotes MG metabolism into D-lactic acid. • Monascin attenuates inflammation and diabetes in vivo.

  3. Accuracy of CT-based attenuation correction in PET/CT bone imaging.

    PubMed

    Abella, Monica; Alessio, Adam M; Mankoff, David A; MacDonald, Lawrence R; Vaquero, Juan Jose; Desco, Manuel; Kinahan, Paul E

    2012-05-07

    We evaluate the accuracy of scaling CT images for attenuation correction of PET data measured for bone. While the standard tri-linear approach has been well tested for soft tissues, the impact of CT-based attenuation correction on the accuracy of tracer uptake in bone has not been reported in detail. We measured the accuracy of attenuation coefficients of bovine femur segments and patient data using a tri-linear method applied to CT images obtained at different kVp settings. Attenuation values at 511 keV obtained with a (68)Ga/(68)Ge transmission scan were used as a reference standard. The impact of inaccurate attenuation images on PET standardized uptake values (SUVs) was then evaluated using simulated emission images and emission images from five patients with elevated levels of FDG uptake in bone at disease sites. The CT-based linear attenuation images of the bovine femur segments underestimated the true values by 2.9 ± 0.3% for cancellous bone regardless of kVp. For compact bone the underestimation ranged from 1.3% at 140 kVp to 14.1% at 80 kVp. In the patient scans at 140 kVp the underestimation was approximately 2% averaged over all bony regions. The sensitivity analysis indicated that errors in PET SUVs in bone are approximately proportional to errors in the estimated attenuation coefficients for the same regions. The variability in SUV bias also increased approximately linearly with the error in linear attenuation coefficients. These results suggest that bias in bone uptake SUVs of PET tracers ranges from 2.4% to 5.9% when using CT scans at 140 and 120 kVp for attenuation correction. Lower kVp scans have the potential for considerably more error in dense bone. This bias is present in any PET tracer with bone uptake but may be clinically insignificant for many imaging tasks. However, errors from CT-based attenuation correction methods should be carefully evaluated if quantitation of tracer uptake in bone is important.

  4. Accuracy of CT-Based Attenuation Correction in PET/CT Bone Imaging

    PubMed Central

    Abella, Monica; Alessio, Adam M.; Mankoff, David A.; MacDonald, Lawrence R.; Vaquero, Juan Jose; Desco, Manuel; Kinahan, Paul E.

    2012-01-01

    We evaluate the accuracy of scaling CT images for attenuation correction of PET data measured for bone. While the standard tri-linear approach has been well-tested for soft tissues, the impact of CT-based attenuation correction on the accuracy of tracer uptake in bone has not been reported in detail. We measured the accuracy of attenuation coefficients of bovine femur segments and patient data using a tri-linear method applied to CT images obtained at different kVp settings. Attenuation values at 511 keV obtained with a 68Ga/68Ge transmission scan were used as a reference standard. The impact of inaccurate attenuation images on PET standardized uptake values (SUVs) was then evaluated using simulated emission images and emission images from five patients with elevated levels of FDG uptake in bone at disease sites. The CT-based linear attenuation images of the bovine femur segments underestimated the true values by 2.9±0.3% for cancellous bone regardless of kVp. For compact bone the underestimation ranged from 1.3% at 140 kVp to 14.1% at 80 kVp. In the patient scans at 140 kVp the underestimation was approximately 2% averaged over all bony regions. The sensitivity analysis indicated that errors in PET SUVs in bone are approximately proportional to errors in the estimated attenuation coefficients for the same regions. The variability in SUV bias also increased approximately linearly with the error in linear attenuation coefficients. These results suggest that bias in bone uptake SUVs of PET tracers range from 2.4% to 5.9% when using CT scans at 140 and 120 kVp for attenuation correction. Lower kVp scans have the potential for considerably more error in dense bone. This bias is present in any PET tracer with bone uptake but may be clinically insignificant for many imaging tasks. However, errors from CT-based attenuation correction methods should be carefully evaluated if quantitation of tracer uptake in bone is important. PMID:22481547

  5. Accuracy of CT-based attenuation correction in PET/CT bone imaging

    NASA Astrophysics Data System (ADS)

    Abella, Monica; Alessio, Adam M.; Mankoff, David A.; MacDonald, Lawrence R.; Vaquero, Juan Jose; Desco, Manuel; Kinahan, Paul E.

    2012-05-01

    We evaluate the accuracy of scaling CT images for attenuation correction of PET data measured for bone. While the standard tri-linear approach has been well tested for soft tissues, the impact of CT-based attenuation correction on the accuracy of tracer uptake in bone has not been reported in detail. We measured the accuracy of attenuation coefficients of bovine femur segments and patient data using a tri-linear method applied to CT images obtained at different kVp settings. Attenuation values at 511 keV obtained with a 68Ga/68Ge transmission scan were used as a reference standard. The impact of inaccurate attenuation images on PET standardized uptake values (SUVs) was then evaluated using simulated emission images and emission images from five patients with elevated levels of FDG uptake in bone at disease sites. The CT-based linear attenuation images of the bovine femur segments underestimated the true values by 2.9 ± 0.3% for cancellous bone regardless of kVp. For compact bone the underestimation ranged from 1.3% at 140 kVp to 14.1% at 80 kVp. In the patient scans at 140 kVp the underestimation was approximately 2% averaged over all bony regions. The sensitivity analysis indicated that errors in PET SUVs in bone are approximately proportional to errors in the estimated attenuation coefficients for the same regions. The variability in SUV bias also increased approximately linearly with the error in linear attenuation coefficients. These results suggest that bias in bone uptake SUVs of PET tracers ranges from 2.4% to 5.9% when using CT scans at 140 and 120 kVp for attenuation correction. Lower kVp scans have the potential for considerably more error in dense bone. This bias is present in any PET tracer with bone uptake but may be clinically insignificant for many imaging tasks. However, errors from CT-based attenuation correction methods should be carefully evaluated if quantitation of tracer uptake in bone is important.

  6. A nonpeptide angiotensin II type 2 receptor agonist does not attenuate postmyocardial infarction left ventricular remodeling in mice.

    PubMed

    Jehle, Alexander B; Xu, Yaqin; Dimaria, Joseph M; French, Brent A; Epstein, Frederick H; Berr, Stuart S; Roy, Rene J; Kemp, Brandon A; Carey, Robert M; Kramer, Christopher M

    2012-04-01

    Cardiac overexpression of the angiotensin II type 2 receptor (AT2 R) attenuates left ventricular (LV) remodeling after myocardial infarction (MI) in transgenic mice. We hypothesized that a novel nonpeptide AT2 R agonist, compound 21 (C21), would attenuate post-MI LV remodeling. Fifty-nine mice were studied for 28 days after 1-hour surgical occlusion-reperfusion of the left anterior descending coronary artery. Immediately thereafter, 23 mice received 0.3 mg·kg·d of C21 via Alzet osmotic minipump, 16 received 10 mg·kg·d of the AT1 R antagonist candesartan in drinking water, and 20 were untreated controls. Cardiac magnetic resonance imaging measured ejection fraction (EF), LV end-systolic, and end-diastolic volumes (ESVI and EDVI) indexed to weight serially post MI. Infarct size was measured on day 1 by late gadolinium-enhanced cardiac magnetic resonance imaging. At baseline, heart rate, blood pressure, EDVI, ESVI, and EF were similar between groups. Mean infarct size (42%-45% of LV mass) was similar between groups. C21-treated animals demonstrated adverse LV remodeling (increased EDVI and ESVI at all post-MI time points) compared with control. Candesartan therapy preserved left ventricular EF at day 28 compared with the C21-treated group. Thus, direct stimulation of the AT2 R by C21 at 0.3 mg·kg·d does not attenuate post-MI LV remodeling in reperfused MI in mice.

  7. Novel GPR119 agonist HD0471042 attenuated type 2 diabetes mellitus.

    PubMed

    Ha, Tae-Young; Kim, Young-Seok; Kim, Chun Hwa; Choi, Hyo-Sun; Yang, Jin; Park, Soo Hyun; Kim, Dae Hoon; Rhee, Jae-Keol

    2014-05-01

    In type 2 diabetes mellitus (T2DM) patients, the gradual loss of pancreatic β-cell function is a characteristic feature of disease progression that is associated with sustained hyperglycemia. Recently, G protein-coupled receptor 119 (GPR119) has been identified as a promising anti-diabetic therapeutic target. It is predominantly expressed in pancreatic β-cells, directly promotes glucose stimulated insulin secretion and indirectly increases glucagon-like peptide 1 (GLP-1) levels reducing appetite and food intake. Activation of GPR119 leads to insulin release in β-cells by increasing intracellular cAMP. Here, we identified a novel structural class of small-molecule GPR119 agonists, HD0471042, consisting of substituted a 3-isopropyl-1,2,4-oxadiazol-piperidine derivative with promising potential for the treatment of T2DM. The GPR119 agonist, HD0471042 increased intracellular cAMP levels in stably human GPR119 expressing CHO cell lines and HIT-T15 cell lines, hamster β-cell line expressing endogenously GPR119. HD0471042, significantly elevated insulin release in INS-1 cells of rat pancreatic β-cell line. In in vivo experiments, a single dose of HD0471042 improved glucose tolerance. Insulin and GLP-1 level were increased in a dose-dependent manner. Treatment with HD0471042 for 6 weeks in diet induced obesity mice and for 4 weeks in ob/ob and db/db mice improved glycemic control and also reduced weight gain in a dose-dependent manner. These data demonstrate that the novel GPR119 agonist, HD0471042, not only effectively controlled glucose levels, but also had an anti-obesity effect, a feature observed with GLP-1. We therefore suggest that HD0471042 represents a new type of anti-diabetes agent with anti-obesity potential for the effective treatment of type 2 diabetes.

  8. The Extravehicular Suit Impact Load Attenuation Study for Use in Astronaut Bone Fracture Prediction

    NASA Technical Reports Server (NTRS)

    Lewandowski, Beth E.; Gilkey, Kelly M.; Sulkowski, Christina M.; Samorezov, Sergey; Myers, Jerry G.

    2011-01-01

    The NASA Integrated Medical Model (IMM) assesses the risk, including likelihood and impact of occurrence, of all credible in-flight medical conditions. Fracture of the proximal femur is a traumatic injury that would likely result in loss of mission if it were to happen during spaceflight. The low gravity exposure causes decreases in bone mineral density which heightens the concern. Researchers at the NASA Glenn Research Center have quantified bone fracture probability during spaceflight with a probabilistic model. It was assumed that a pressurized extravehicular activity (EVA) suit would attenuate load during a fall, but no supporting data was available. The suit impact load attenuation study was performed to collect analogous data. METHODS: A pressurized EVA suit analog test bed was used to study how the offset, defined as the gap between the suit and the astronaut s body, impact load magnitude and suit operating pressure affects the attenuation of impact load. The attenuation data was incorporated into the probabilistic model of bone fracture as a function of these factors, replacing a load attenuation value based on commercial hip protectors. RESULTS: Load attenuation was more dependent on offset than on pressurization or load magnitude, especially at small offsets. Load attenuation factors for offsets between 0.1 - 1.5 cm were 0.69 +/- 0.15, 0.49 +/- 0.22 and 0.35 +/- 0.18 for mean impact forces of 4827, 6400 and 8467 N, respectively. Load attenuation factors for offsets of 2.8 - 5.3 cm were 0.93 +/- 0.2, 0.94 +/- 0.1 and 0.84 +/- 0.5, for the same mean impact forces. Reductions were observed in the 95th percentile confidence interval of the bone fracture probability predictions. CONCLUSIONS: The reduction in uncertainty and improved confidence in bone fracture predictions increased the fidelity and credibility of the fracture risk model and its benefit to mission design and operational decisions.

  9. Lobeglitazone, a Novel Peroxisome Proliferator-Activated Receptor γ Agonist, Attenuates Renal Fibrosis Caused by Unilateral Ureteral Obstruction in Mice

    PubMed Central

    Seo, Jung Beom; Jung, Yun-A; Seo, Hye-Young; Kang, Sun Hee; Jeon, Hui-Jeon; Lee, Jae Man; Lee, Sungwoo; Kim, Jung-Guk; Lee, In-Kyu

    2017-01-01

    Background Renal tubulointerstitial fibrosis is a common feature of the final stage of nearly all cause types of chronic kidney disease. Although classic peroxisome proliferator-activated receptor γ (PPARγ) agonists have a protective effect on diabetic nephropathy, much less is known about their direct effects in renal fibrosis. This study aimed to investigate possible beneficial effects of lobeglitazone, a novel PPARγ agonist, on renal fibrosis in mice. Methods We examined the effects of lobeglitazone on renal tubulointerstitial fibrosis in unilateral ureteral obstruction (UUO) induced renal fibrosis mice. We further defined the role of lobeglitazone on transforming growth factor (TGF)-signaling pathways in renal tubulointerstitial fibrosis through in vivo and in vitro study. Results Through hematoxylin/eosin and sirius red staining, we observed that lobeglitazone effectively attenuates UUO-induced renal atrophy and fibrosis. Immunohistochemical analysis in conjunction with quantitative reverse transcription polymerase chain reaction and Western blot analysis revealed that lobeglitazone treatment inhibited UUO-induced upregulation of renal Smad-3 phosphorylation, α-smooth muscle actin, plasminogen activator inhibitor 1, and type 1 collagen. In vitro experiments with rat mesangial cells and NRK-49F renal fibroblast cells suggested that the effects of lobeglitazone on UUO-induced renal fibrosis are mediated by inhibition of the TGF-β/Smad signaling pathway. Conclusion The present study demonstrates that lobeglitazone has a protective effect on UUO-induced renal fibrosis, suggesting that its clinical applications could extend to the treatment of non-diabetic origin renal disease. PMID:28256116

  10. Frequency Specific Ultrasound Attenuation Is Sensitive to Trabecular Bone Structure

    PubMed Central

    Lin, Wei; Serra-Hsu, Frederick; Chen, Jiqi; Qin, Yi-Xian

    2012-01-01

    This study investigated the efficacy of frequency modulated ultrasound attenuation in the assessment of the trabecular structural properties. Four frequency modulated signals were created to represent four frequency bands centered at 500 kHz, 900 kHz, 1.3 MHz and 1.7 MHz with the bandwidth of 400 kHz. Five one-centimeter trabecular cubes were harvested from fresh bovine distal femur. The cubes underwent four steps of demineralization process to expand the sample size to twenty five with the greater variations of the structural properties for the better correlation study. Pearson correlation study was performed between the ultrasound attenuation in four frequency bands and the trabecular structural properties. The results showed that correlations of frequency modulated ultrasound attenuation to the trabecular structural properties are dependent on frequency bands. The attenuation in proximal-distal orientation had the highest correlation to BV/TV (R2=0.73, p<0.001) and trabecular thickness (R2=0.50, p<0.001) at the frequency band centered at 1.7 MHz. It was equivalent in the four frequency bands in correlation to the trabecular number (average R2=0.80, p<0.001) and to the trabecular separation (average R2 =0.83, p<0.001). The attenuation in anterio-posterial orientation had the highest correlation to BV/TV (R2=0.80, p<0.001) and trabecular thickness (R2=0.71, p<0.001) at the frequency band centered at 1.3 MHz. The attenuation in the first frequency band was the most sensitive to the trabecular number (R2=0.71, p<0.001) and trabecular separation (R2=0.80, p<0.001). No significant correlation was observed for the attenuation in medial-lateral orientation across the four frequency bands. PMID:22975035

  11. Visceral adiposity is negatively associated with bone density and muscle attenuation.

    PubMed

    Zhang, Peng; Peterson, Mark; Su, Grace L; Wang, Stewart C

    2015-02-01

    The storage of adipose tissue in ectopic compartments is a hallmark attribute linking greater body mass index (BMI) with cardiometabolic diseases. Despite ample evidence to confirm that increased visceral adipose tissue (VAT) deposition occurs with obesity, the interrelations between altered fat partitioning and regional muscle and bone quality are less well understood. We examined the association between adiposity and spinal muscle and bone quality across a large, heterogeneous cohort of adults. We identified 8833 thoracic or abdominal computed tomography scans from patients in the University of Michigan Health System who were aged 18-64.9 y. We measured trabecular bone densities, cortical bone densities, VAT areas, and subcutaneous adipose tissue (SAT) areas at vertebral levels T7 to L5. Psoas muscle attenuation (an indicator of fat infiltration in muscle) was measured at the L4 level. Muscle attenuation as well as trabecular and cortical bone densities revealed negative correlations with BMI, SAT, and VAT. The correlation between BMI and psoas attenuation was -0.321, between BMI and the density of cortical bone was -0.250, and between BMI and trabecular bone was -0.143 (all P < 0.001). However, correlations between VAT and lower muscle attenuation were stronger as were those between VAT and lower bone densities. Inverse correlations between VAT and densities of psoas muscle and cortical and trabecular bone were -0.460, -0.407, and -0.434, respectively (P < 0.001). Even after adjustment for age, sex, and BMI, partial correlations between VAT, muscle attenuation, and bone densities remained significant at -0.250, -0.119, and -0.216, respectively (P < 0.001). Contrary to previous reports that high body mass is associated with increased bone quality, our data show a significant negative association between BMI and muscle and bone densities, suggesting fat infiltration into these tissues. More importantly, correlations between VAT and decreased bone and muscle

  12. GABA(B) receptor agonist baclofen attenuates the development and expression of d-methamphetamine-induced place preference in rats.

    PubMed

    Li, S M; Yin, L L; Ren, Y H; Pan, L S; Zheng, J W

    2001-12-07

    The present study investigated the effect of systemic administration of the GABA(B) receptor agonist, baclofen, on the development and expression of d-methamphetamine (d-MA)-induced place preference in male Wistar rats. Using a biased and 8-day schedule of conditioning, it was found that administration of d-MA (0.5 mg/kg, i.p.) produced significant place preference. The administration of baclofen (2.5 and 5.0 mg/kg, i.p.) 30 min prior to the exposure to d-MA attenuated the development of d-MA-induced place preference (p<0.05). In addition, when it was acutely administered 30 min prior to the testing session of an already established d-MA place preference, baclofen (1.25-5.0 mg/kg, i.p.) attenuated the expression of this conditioned response in a dose-dependent manner. These results showed that baclofen suppressed the rewarding effect produced by d-MA and may be potentially effective in the treatment of methamphetamine dependence and craving.

  13. Coadministration of puerarin (low dose) and zinc attenuates bone loss and suppresses bone marrow adiposity in ovariectomized rats.

    PubMed

    Liu, Hao; Li, Wei; Ge, Xiyuan; Jia, Shengnan; Li, Binbin

    2016-12-01

    Puerarin is a phytoestrogen that shows osteogenic effects. Meanwhile, zinc stimulates bone formation and inhibits bone resorption. The study aims to investigate the effects of coadministration of puerarin (low dose) and zinc on bone formation in ovariectomized rats. Co-administration or use alone of puerarin (low dose) and/or zinc were gavaged in OVX rats. The estrogen-like effects were detected by the uterus weight, the histologic observation and the IGF-1 protein expression. The osteogenic effects were determined by bone histomorphometric and mechanical parameters, osteogenic and adipogenic blood markers, and so on. The results showed that oral administration of puerarin (low dose) plus zinc didn't significantly increase uterus weight. The glandular epithelial of endometrium had no proliferation and no protein expression of IGF-1. Moreover, co-administration attenuated bone loss and biomechanical decrease more than single use of puerarin or zinc (p<0.05). Next, combined administration of puerarin and zinc promoted the serological level of osteocalcin, bone marrow stromal cell (BMSC) proliferation, and the expression of alkaline phosphatase (ALP), and suppressed the serological level of adiponectin and adiposity in bone marrow (BM). In conclusion, co-administrated puerarin (low dose) and zinc can partially reverse OVX-induced bone loss and suppress the adiposity of BM in rats, which shed light on the potential use of puerarin and zinc in the treatment of osteoporosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. An extravehicular suit impact load attenuation study to improve astronaut bone fracture prediction.

    PubMed

    Sulkowski, Christina M; Gilkey, Kelly M; Lewandowski, Beth E; Samorezov, Sergey; Myers, Jerry G

    2011-04-01

    Understanding the contributions to the risk of bone fracture during spaceflight is essential for mission success. A pressurized extravehicular activity (EVA) suit analogue test bed was developed, impact load attenuation data were obtained, and the load at the hip of an astronaut who falls to the side during an EVA was characterized. Offset (representing the gap between the EVA suit and the astronaut's body), impact load magnitude, and EVA suit operating pressure were factors varied in the study. The attenuation data were incorporated into a probabilistic model of bone fracture risk during spaceflight, replacing the previous load attenuation value that was based on commercial hip protector data. Load attenuation was more dependent on offset than on pressurization or load magnitude, especially at small offset values. Load attenuation factors for offsets between 0.1-1.5 cm were 0.69 +/- 0.15, 0.49 +/- 0.22, and 0.35 +/- 0.18 for mean impact forces of 4827, 6400, and 8467 N, respectively. Load attenuation factors for offsets of 2.8-5.3 cm were 0.93 +/- 0.2, 0.94 +/- 0.1, and 0.84 +/- 0.5 for the same mean impact forces. The mean and 95th percentile bone fracture risk index predictions were each reduced by 65-83%. The mean and 95th percentile bone fracture probability predictions were both reduced approximately 20-50%. The reduction in uncertainty and improved confidence in bone fracture predictions increased the fidelity and credibility of the fracture risk model and its benefit to mission design and in-flight operational decisions.

  15. A PPAR-gamma agonist attenuates pulmonary injury induced by irradiation in a murine model.

    PubMed

    Mangoni, Monica; Sottili, Mariangela; Gerini, Chiara; Bonomo, Pierluigi; Bottoncetti, Anna; Castiglione, Francesca; Franzese, Ciro; Cassani, Sara; Greto, Daniela; Masoni, Tatiana; Meattini, Icro; Pallotta, Stefania; Passeri, Alessandro; Pupi, Alberto; Vanzi, Eleonora; Biti, Giampaolo; Livi, Lorenzo

    2015-12-01

    Due to its anti-inflammatory, antifibrotic and antineoplastic properties, the PPAR-γ agonist rosiglitazone is of interest in the prevention and therapy of radiation-induced pulmonary injury. We evaluated the radioprotective effects of rosiglitazone in a murine model of pulmonary damage to determine whether radioprotection was selective for normal and tumor tissues. Lungs in C57BL/6J mice were irradiated (19 Gy) with or without rosiglitazone (RGZ, 5mg/kg/day for 16 weeks, oral gavage). Computed tomography (CT) was performed and Hounsfield Units (HU) were determined during the observation period. Histological analysis and evaluation of fibrosis/inflammatory markers by western blot were performed at 16 weeks. A549 tumor-bearing CD1 mice were irradiated (16 Gy) with or without RGZ, and tumor volumes were measured at 35 days. Rosiglitazone reduced radiologic and histologic signs of fibrosis, inflammatory infiltrate, alterations to alveolar structures, and HU lung density that was increased due to irradiation. RGZ treatment also significantly decreased Col1, NF-kB and TGF-β expression and increased Bcl-2 protein expression compared to the irradiation group and reduced A549 clonogenic survival and xenograft tumor growth. Rosiglitazone exerted a protective effect on normal tissues in radiation-induced pulmonary injury, while irradiated lung cancer cells were not protected in vivo and in vitro. Thus, rosiglitazone could be proposed as a radioprotective agent in the treatment of lung cancer. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. The peroxisome proliferator-activated receptor alpha agonist fenofibrate attenuates alcohol self-administration in rats.

    PubMed

    Haile, Colin N; Kosten, Therese A

    2017-04-01

    Fibrates are a class of medications used to treat hypercholesterolemia and dyslipidemia that target nuclear peroxisome proliferator-activated receptors (PPARs). Studies have shown the PPARα agonist fenofibrate decreases voluntary EtOH consumption however its impact on the reinforcing and motivational effects of EtOH is unknown. We evaluated the ability of fenofibrate (25, 50 and 100 mg/kg), to alter EtOH (10%, w/v) and sucrose (2%, w/v) operant self-administration in rats under a FR2 schedule of reinforcement over four days and under a progressive ratio (PR) schedule on day five of treatment. Results showed fenofibrate dose-dependently decreased EtOH self-administration under both schedules of reinforcement with the greatest effects seen after four to five days of treatment. Fenofibrate decreased responding for sucrose only under the PR schedule of reinforcement and this effect was not dose-dependent. These findings provide further evidence for fenofibrate as a potential treatment for alcohol use disorder in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Connexin 43 deficiency attenuates loss of trabecular bone and prevents suppression of cortical bone formation during unloading.

    PubMed

    Lloyd, Shane A; Lewis, Gregory S; Zhang, Yue; Paul, Emmanuel M; Donahue, Henry J

    2012-11-01

    Connexin 43 (Cx43) is the most abundant gap junction protein in bone and has been demonstrated as an integral component of skeletal homeostasis. In the present study, we sought to further refine the role of Cx43 in the response to mechanical unloading by subjecting skeletally mature mice with a bone-specific deletion of Cx43 (cKO) to 3 weeks of mechanical unloading via hindlimb suspension (HLS). The HLS model was selected to recapitulate the effects of skeletal unloading due to prolonged bed rest, reduced activity associated with aging, and spaceflight microgravity. At baseline, the cortical bone of cKO mice displayed an osteopenic phenotype, with expanded cortices, decreased cortical thickness, decreased bone mineral density, and increased porosity. There was no baseline trabecular phenotype. After 3 weeks of HLS, wild-type (WT) mice experienced a substantial decline in trabecular bone volume fraction, connectivity density, trabecular thickness, and trabecular tissue mineral density. These deleterious effects were attenuated in cKO mice. Conversely, there was a similar and significant amount of cortical bone loss in both WT and cKO. Interestingly, mechanical testing revealed a greater loss of strength and rigidity for cKO during HLS. Analysis of double-label quantitative histomorphometry data demonstrated a substantial decrease in bone formation rate, mineralizing surface, and mineral apposition rate at both the periosteal and endocortical surfaces of the femur after unloading of WT mice. This suppression of bone formation was not observed in cKO mice, in which parameters were maintained at baseline levels. Taken together, the results of the present study indicate that Cx43 deficiency desensitizes bone to the effects of mechanical unloading, and that this may be due to an inability of mechanosensing osteocytes to effectively communicate the unloading state to osteoblasts to suppress bone formation. Cx43 may represent a novel therapeutic target for investigation as

  18. Insulin resistance and increased lipolysis in bone marrow derived adipocytes stimulated with agonists of Toll-like receptors.

    PubMed

    Franchini, M; Monnais, E; Seboek, D; Radimerski, T; Zini, E; Kaufmann, K; Lutz, T; Reusch, C; Ackermann, M; Muller, B; Linscheid, P

    2010-09-01

    Our objectives were to identify Toll-like receptors (TLRs) in human bone marrow derived adipocytes, to test specific TLR agonists for their ability to induce a proinflammatory response, and to investigate possible metabolic effects after TLR activation, in particular, those associated with insulin resistance and lipolysis. Mesenchymal stem cells were isolated from human bone marrow and differentiated into adipocytes. Total RNA before or after stimulation with agonists specific for TLR was extracted for analysis of expression of TLRs proinflammatory signals and molecules involved in glucose metabolism (IRS-1 and GLUT4). Furthermore, cytokine protein expression was measured from cell lysates. Finally, insulin induced glucose uptake and lipolysis were measured. Human bone marrow-derived adipocytes express TLR1-10. They react to stimulation with specific ligands with expression of inflammatory markers (IL-1beta, IL-6, TNFalpha, IL-8, MCP-1) at the RNA and protein levels. IRS-1 and GLUT4 expression was downregulated after stimulation with the TLR4 and TLR3 specific ligands LPS and poly (I:C), respectively. Insulin-induced glucose uptake was decreased and lipolysis increased. We conclude that adipocytes express TLR 1-10 and react to agonists specific for TLR 1-6. As a consequence proinflammatory cytokine are induced, in particular, IL-6, IL-8, and MCP-1. Since stimulation is followed by decreased insulin-induced glucose uptake and increased lipolysis we conclude that TLRs may be important linking molecules in the generation of insulin resistance in fat tissue.

  19. Chronic administration of Glucagon-like peptide-1 receptor agonists improves trabecular bone mass and architecture in ovariectomised mice.

    PubMed

    Pereira, M; Jeyabalan, J; Jørgensen, C S; Hopkinson, M; Al-Jazzar, A; Roux, J P; Chavassieux, P; Orriss, I R; Cleasby, M E; Chenu, C

    2015-12-01

    Some anti-diabetic therapies can have adverse effects on bone health and increase fracture risk. In this study, we tested the skeletal effects of chronic administration of two Glucagon-like peptide-1 receptor agonists (GLP-1RA), increasingly used for type 2 diabetes treatment, in a model of osteoporosis associated bone loss and examined the expression and activation of GLP-1R in bone cells. Mice were ovariectomised (OVX) to induce bone loss and four weeks later they were treated with Liraglutide (LIR) 0.3mg/kg/day, Exenatide (Ex-4) 10 μg/kg/day or saline for four weeks. Mice were injected with calcein and alizarin red prior to euthanasia, to label bone-mineralising surfaces. Tibial micro-architecture was determined by micro-CT and bone formation and resorption parameters measured by histomorphometric analysis. Serum was collected to measure calcitonin and sclerostin levels, inhibitors of bone resorption and formation, respectively. GLP-1R mRNA and protein expression were evaluated in the bone, bone marrow and bone cells using RT-PCR and immunohistochemistry. Primary osteoclasts and osteoblasts were cultured to evaluate the effect of GLP-1RA on bone resorption and formation in vitro. GLP-1RA significantly increased trabecular bone mass, connectivity and structure parameters but had no effect on cortical bone. There was no effect of GLP-1RA on bone formation in vivo but an increase in osteoclast number and osteoclast surfaces was observed with Ex-4. GLP-1R was expressed in bone marrow cells, primary osteoclasts and osteoblasts and in late osteocytic cell line. Both Ex-4 and LIR stimulated osteoclastic differentiation in vitro but slightly reduced the area resorbed per osteoclast. They had no effect on bone nodule formation in vitro. Serum calcitonin levels were increased and sclerostin levels decreased by Ex-4 but not by LIR. Thus, GLP-1RA can have beneficial effects on bone and the expression of GLP-1R in bone cells may imply that these effects are exerted directly

  20. Bone resorption starts at 14 days of treatment with gonadotropin-releasing hormone agonist in in vitro fertilization cycles.

    PubMed

    Yilmaz, H; Ozgur, K; Isikoglu, M; Sonmez, C; Uner, M

    2004-07-01

    The effect of gonadotropin-releasing hormone agonist (GnRH-a) use on bone turnover was investigated in a prospective cohort study of female patients undergoing in vitro fertilization (IVF) treatment. In 46 couples diagnosed with male-factor infertility, the women underwent a long step-down ovulation induction protocol. Urinary cross-linked N-telopeptide (uNTx) level was used to demonstrate bone turnover rate and was measured at the first day of GnRH-a administration, the first day of gonadotropin administration, the day after human chorionic gonadotropin injection and 12 days after embryo transfer. Urinary NTx levels (mean+/-standard deviation (SD)) were 71+/-34, 81+/-40, 81+/-50 and 83+/-47 nmol BCE/mmol creatinine (BCE, bone collagen equivalents), respectively. There was no statistically significant difference between the four measurements (p = 0.28). In 19 women GnRH-a was administered for > or = 14 days. Urinary NTx values of this group and the remaining 27 patients after GnRH-a treatment were 96.2+/-40.7 and 71.5+/-36.8 nmol BCE/mmol creatinine (mean+/-SD), respectively. The difference between these groups was statistically significant (p=0.038). These findings suggest that < 14 days' use of GnRH agonist in IVF patients has no effect on bone metabolism. To our knowledge, this is the first study demonstrating that the effect of agonists on bone metabolism starts as soon as estradiol suppression has started.

  1. The galanin receptor agonist, galnon, attenuates cocaine-induced reinstatement and dopamine overflow in the frontal cortex.

    PubMed

    Ogbonmwan, Yvonne E; Sciolino, Natale R; Groves-Chapman, Jessica L; Freeman, Kimberly G; Schroeder, Jason P; Edwards, Gaylen L; Holmes, Philip V; Weinshenker, David

    2015-07-01

    Relapse represents one of the most significant problems in the long-term treatment of drug addiction. Cocaine blocks plasma membrane monoamine transporters and increases dopamine (DA) overflow in the brain, and DA is critical for the motivational and primary reinforcing effects of the drug as well as cocaine-primed reinstatement of cocaine seeking in rats, a model of relapse. Thus, modulators of the DA system may be effective for the treatment of cocaine dependence. The endogenous neuropeptide galanin inhibits DA transmission, and both galanin and the synthetic galanin receptor agonist, galnon, interfere with some rewarding properties of cocaine. The purpose of this study was to further assess the effects of galnon on cocaine-induced behaviors and neurochemistry in rats. We found that galnon attenuated cocaine-induced motor activity, reinstatement and DA overflow in the frontal cortex at a dose that did not reduce baseline motor activity, stable self-administration of cocaine, baseline extracellular DA levels or cocaine-induced DA overflow in the nucleus accumbens (NAc). Similar to cocaine, galnon had no effect on stable food self-administration but reduced food-primed reinstatement. These results indicate that galnon can diminish cocaine-induced hyperactivity and relapse-like behavior, possibly in part by modulating DA transmission in the frontal cortex. © 2014 Society for the Study of Addiction.

  2. SKF-38393, a dopamine receptor agonist, attenuates 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity.

    PubMed

    Muralikrishnan, D; Ebadi, M

    2001-02-23

    Parkinson's disease (PD) is characterized by progressive degeneration of nigrostriatal dopaminergic neurons. Several factors such as inhibition of the mitochondrial respiration, generation of hydroxyl radicals and reduced free radical defense mechanisms causing oxidative stress, have been postulated to contribute to the degeneration of dopaminergic neurons. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treated animals is a useful experimental model of PD, exhibiting most of the clinical features, as well as the main biochemical and pathologic symptoms of the disease. In the present study, we have examined a dopaminergic (D1) receptor agonist, SKF-38393 HCl (SKF) for its possible neuroprotective action against MPTP-induced insults on dopaminergic neurons. MPTP is converted by monoamine oxidase-B (MAO-B) to its neurotoxic metabolite 1-methyl-4-phenyl-pyridinium (MPP+), which is then taken up into the dopaminergic neurons. SKF-38393 had no effects either on total or monoamine oxidase B in the striatum. SKF-38393 blocked the MPTP-induced depletion of glutathione and attenuated MPTP-induced depletion of dopamine. Furthermore, it enhanced the activity of superoxide dismutase and hence mimicked the action of selegiline. The results of these studies are interpreted to suggest that SKF-38393 may prove a valuable drug in the treatment of Parkinson's disease.

  3. Partial agonist, telmisartan, maintains PPARγ serine 112 phosphorylation, and does not affect osteoblast differentiation and bone mass.

    PubMed

    Kolli, Vipula; Stechschulte, Lance A; Dowling, Abigail R; Rahman, Sima; Czernik, Piotr J; Lecka-Czernik, Beata

    2014-01-01

    Peroxisome proliferator activated receptor gamma (PPARγ) controls both glucose metabolism and an allocation of marrow mesenchymal stem cells (MSCs) toward osteoblast and adipocyte lineages. Its activity is determined by interaction with a ligand which directs posttranscriptional modifications of PPARγ protein including dephosphorylation of Ser112 and Ser273, which results in acquiring of pro-adipocytic and insulin-sensitizing activities, respectively. PPARγ full agonist TZD rosiglitazone (ROSI) decreases phosphorylation of both Ser112 and Ser273 and its prolonged use causes bone loss in part due to diversion of MSCs differentiation from osteoblastic toward adipocytic lineage. Telmisartan (TEL), an anti-hypertensive drug from the class of angiotensin receptor blockers, also acts as a partial PPARγ agonist with insulin-sensitizing and a weak pro-adipocytic activity. TEL decreased S273pPPARγ and did not affect S112pPPARγ levels in a model of marrow MSC differentiation, U-33/γ2 cells. In contrast to ROSI, TEL did not affect osteoblast phenotype and actively blocked ROSI-induced anti-osteoblastic activity and dephosphorylation of S112pPPARγ. The effect of TEL on bone was tested side-by-side with ROSI. In contrast to ROSI, TEL administration did not affect bone mass and bone biomechanical properties measured by micro-indentation method and did not induce fat accumulation in bone, and it partially protected from ROSI-induced bone loss. In addition, TEL induced "browning" of epididymal white adipose tissue marked by increased expression of UCP1, FoxC2, Wnt10b and IGFBP2 and increased overall energy expenditure. These studies point to the complexity of mechanisms by which PPARγ acquires anti-osteoblastic and pro-adipocytic activities and suggest an importance of Ser112 phosphorylation status as being a part of the mechanism regulating this process. These studies showed that TEL acts as a full PPARγ agonist for insulin-sensitizing activity and as a partial agonist

  4. Enhanced Osteogenesis of Adipose-Derived Stem Cells by Regulating Bone Morphogenetic Protein Signaling Antagonists and Agonists

    PubMed Central

    Fan, Jiabing; Im, Choong Sung; Guo, Mian; Cui, Zhong-Kai; Fartash, Armita; Kim, Soyon; Patel, Nikhil; Bezouglaia, Olga; Wu, Benjamin M.; Wang, Cun-Yu

    2016-01-01

    Although adipose-derived stem cells (ASCs) are an attractive cell source for bone tissue engineering, direct use of ASCs alone has had limited success in the treatment of large bone defects. Although bone morphogenetic proteins (BMPs) are believed to be the most potent osteoinductive factors to promote osteogenic differentiation of ASCs, their clinical applications require supraphysiological dosage, leading to high medical burden and adverse side effects. In the present study, we demonstrated an alternative approach that can effectively complement the BMP activity to maximize the osteogenesis of ASCs without exogenous application of BMPs by regulating levels of antagonists and agonists to BMP signaling. Treatment of ASCs with the amiloride derivative phenamil, a positive regulator of BMP signaling, combined with gene manipulation to suppress the BMP antagonist noggin, significantly enhanced osteogenic differentiation of ASCs through increased BMP–Smad signaling in vitro. Furthermore, the combination approach of noggin suppression and phenamil stimulation enhanced the BMP signaling and bone repair in a mouse calvarial defect model by adding noggin knockdown ASCs to apatite-coated poly(lactic-coglycolic acid) scaffolds loaded with phenamil. These results suggest novel complementary osteoinductive strategies that could maximize activity of the BMP pathway in ASC bone repair while reducing potential adverse effects of current BMP-based therapeutics. Significance Although stem cell-based tissue engineering strategy offers a promising alternative to repair damaged bone, direct use of stem cells alone is not adequate for challenging healing environments such as in large bone defects. This study demonstrates a novel strategy to maximize bone formation pathways in osteogenic differentiation of mesenchymal stem cells and functional bone formation by combining gene manipulation with a small molecule activator toward osteogenesis. The findings indicate promising stem cell

  5. Numerical and experimental study on the wave attenuation in bone--FDTD simulation of ultrasound propagation in cancellous bone.

    PubMed

    Nagatani, Yoshiki; Mizuno, Katsunori; Saeki, Takashi; Matsukawa, Mami; Sakaguchi, Takefumi; Hosoi, Hiroshi

    2008-11-01

    In cancellous bone, longitudinal waves often separate into fast and slow waves depending on the alignment of bone trabeculae in the propagation path. This interesting phenomenon becomes an effective tool for the diagnosis of osteoporosis because wave propagation behavior depends on the bone structure. Since the fast wave mainly propagates in trabeculae, this wave is considered to reflect the structure of trabeculae. For a new diagnosis method using the information of this fast wave, therefore, it is necessary to understand the generation mechanism and propagation behavior precisely. In this study, the generation process of fast wave was examined by numerical simulations using elastic finite-difference time-domain (FDTD) method and experimental measurements. As simulation models, three-dimensional X-ray computer tomography (CT) data of actual bone samples were used. Simulation and experimental results showed that the attenuation of fast wave was always higher in the early state of propagation, and they gradually decreased as the wave propagated in bone. This phenomenon is supposed to come from the complicated propagating paths of fast waves in cancellous bone.

  6. Protein malnutrition attenuates bone anabolic response to PTH in female rats.

    PubMed

    Ammann, P; Zacchetti, G; Gasser, J A; Lavet, C; Rizzoli, R

    2015-02-01

    PTH is indicated for the treatment of severe osteoporosis. Elderly osteoporotic patients frequently suffer from protein malnutrition, which may contribute to bone loss. It is unknown whether this malnutrition may affect the response to PTH. Therefore, the aim of the present study was to assess whether an isocaloric low-protein (LP) diet may influence the bone anabolic response to intermittent PTH in 6-month-old female rats. Six-month-old female rats were either pair fed an isocaloric LP diet (2.5% casein) or a normal-protein (NP) diet (15% casein) for 2 weeks. The rats continued on their respective diet while being treated with 5- or 40-μg/kg recombinant human PTH amino-terminal fragment 1-34 (PTH-[1-34]) daily, or with vehicle for 4 weeks. At the end of this period, areal bone mineral density, bone mineral content, microstructure, and bone strength in axial compression of proximal tibia or 3-point bending for midshaft tibia tests were measured. Blood was collected for the determination of IGF-I and osteocalcin. After 4 weeks of PTH-(1-34), the dose-dependent increase of proximal tibia bone mineral density, trabecular microstructure variables, and bone strength was attenuated in rats fed a LP diet as compared with rats on a NP intake. At the level of midshaft tibia cortical bone, PTH-(1-34) exerted an anabolic effect only in the NP but not in the LP diet group. Protein malnutrition was associated with lower IGF-I levels. Protein malnutrition attenuates the bone anabolic effects of PTH-(1-34) in rats. These results suggest that a sufficient protein intake should be recommended for osteoporotic patients undergoing PTH therapy.

  7. Numerical investigation of ultrasonic attenuation through 2D trabecular bone structures reconstructed from CT scans and random realizations.

    PubMed

    Gilbert, Robert P; Guyenne, Philippe; Li, Jing

    2014-02-01

    In this paper, we compare ultrasound interrogations of actual CT-scanned images of trabecular bone with artificial randomly constructed bone. Even though it is known that actual bone does not have randomly distributed trabeculae, we find that the ultrasound attenuations are close enough to cast doubt on any microstructural information, such as trabeculae width and distance between trabeculae, being gleaned from such experiments. More precisely, we perform numerical simulations of ultrasound interrogation on cancellous bone to investigate the phenomenon of ultrasound attenuation as a function of excitation frequency and bone porosity. The theoretical model is based on acoustic propagation equations for a composite fluid-solid material and is solved by a staggered-grid finite-difference scheme in the time domain. Numerical experiments are performed on two-dimensional bone samples reconstructed from CT-scanned images of real human calcaneus and from random distributions of fluid-solid particles generated via the turning bands method. A detailed comparison is performed on various parameters such as the attenuation rate and speed of sound through the bone samples as well as the normalized broadband ultrasound attenuation coefficient. Comparing results from these two types of bone samples allows us to assess the role of bone microstructure in ultrasound attenuation. It is found that the random model provides suitable bone samples for ultrasound interrogation in the transverse direction of the trabecular network.

  8. Klotho preservation via histone deacetylase inhibition attenuates chronic kidney disease-associated bone injury in mice

    PubMed Central

    Lin, Wenjun; Li, Yanning; chen, Fang; Yin, Shasha; Liu, Zhihong; Cao, Wangsen

    2017-01-01

    Bone loss and increased fracture are the devastating outcomes of chronic kidney disease-mineral and bone disorder (CKD-MBD) resulting from Klotho deficit-related mineral disturbance and hyperparathyroidism. Because Klotho down-regulation after renal injury is presumably affected by aberrant histone deacetylase (HDAC) activities, here we assess whether HDAC inhibition prevents Klotho loss and attenuates the CKD-associated bone complication in a mouse model of CKD-MBD. Mice fed adenine-containing diet developed the expected renal damage, a substantial Klotho loss and the deregulated key factors causally affecting bone remodeling, which were accompanied by a marked reduction of bone mineral density. Intriguingly, administration of a potent HDAC inhibitor trichostatin A (TSA) impressively alleviated the Klotho deficit and the observed alterations of serum, kidney and bone. TSA prevented Klotho loss by increasing the promoter-associated histone acetylation, therefore increasing Klotho transcription. More importantly the mice lacking Klotho by siRNA interference largely abolished the TSA protections against the serum and renal abnormalities, and the deranged bone micro-architectures. Thus, our study identified Klotho loss as a key event linking HDAC deregulation to the renal and bone injuries in CKD-MBD mice and demonstrated the therapeutic potentials of endogenous Klotho restoration by HDAC inhibition in treating CKD and the associated extrarenal complications. PMID:28387374

  9. Raloxifene administration in women treated with gonadotropin-releasing hormone agonist for uterine leiomyomas: effects on bone metabolism.

    PubMed

    Palomba, Stefano; Orio, Francesco; Morelli, Michele; Russo, Tiziana; Pellicano, Massimilano; Nappi, Carmine; Mastrantonio, Pasquale; Lombardi, Gaetano; Colao, Annamaria; Zullo, Fulvio

    2002-10-01

    This prospective randomized, single-blind, placebo-controlled clinical trial was performed to evaluate the efficacy of raloxifene in preventing the bone loss associated with GnRH agonist (GnRH-a) administration. One hundred premenopausal women with uterine leiomyomas were treated with leuprolide acetate depot at a dosage of 3.75 mg/d for 28 d and then randomized into two groups to receive raloxifene hydrochloride at 60 mg/d (group A) or placebo (1 tablet/d; group B). Bone mineral density (BMD) and serum bone metabolism markers were evaluated at admission and after six treatment cycles. Posttreatment BMD differed significantly from baseline BMD in group B but not in group A. BMD was significantly higher in group A than in group B. In group A, serum osteocalcin and bone alkaline phosphatase levels and urinary deoxypyridinoline and pyrilinks-D excretion were unchanged vs. baseline. Differently, posttreatment concentrations of these bone turnover markers were significantly lower in group B compared with baseline and group A values. In conclusion, raloxifene prevents GnRH-a related bone loss in premenopausal women with uterine leiomyomas.

  10. Determining attenuation properties of interfering fast and slow ultrasonic waves in cancellous bone

    PubMed Central

    Nelson, Amber M.; Hoffman, Joseph J.; Anderson, Christian C.; Holland, Mark R.; Nagatani, Yoshiki; Mizuno, Katsunori; Matsukawa, Mami; Miller, James G.

    2011-01-01

    Previous studies have shown that interference between fast waves and slow waves can lead to observed negative dispersion in cancellous bone. In this study, the effects of overlapping fast and slow waves on measurements of the apparent attenuation as a function of propagation distance are investigated along with methods of analysis used to determine the attenuation properties. Two methods are applied to simulated data that were generated based on experimentally acquired signals taken from a bovine specimen. The first method uses a time-domain approach that was dictated by constraints imposed by the partial overlap of fast and slow waves. The second method uses a frequency-domain log-spectral subtraction technique on the separated fast and slow waves. Applying the time-domain analysis to the broadband data yields apparent attenuation behavior that is larger in the early stages of propagation and decreases as the wave travels deeper. In contrast, performing frequency-domain analysis on the separated fast waves and slow waves results in attenuation coefficients that are independent of propagation distance. Results suggest that features arising from the analysis of overlapping two-mode data may represent an alternate explanation for the previously reported apparent dependence on propagation distance of the attenuation coefficient of cancellous bone. PMID:21973378

  11. Determining attenuation properties of interfering fast and slow ultrasonic waves in cancellous bone.

    PubMed

    Nelson, Amber M; Hoffman, Joseph J; Anderson, Christian C; Holland, Mark R; Nagatani, Yoshiki; Mizuno, Katsunori; Matsukawa, Mami; Miller, James G

    2011-10-01

    Previous studies have shown that interference between fast waves and slow waves can lead to observed negative dispersion in cancellous bone. In this study, the effects of overlapping fast and slow waves on measurements of the apparent attenuation as a function of propagation distance are investigated along with methods of analysis used to determine the attenuation properties. Two methods are applied to simulated data that were generated based on experimentally acquired signals taken from a bovine specimen. The first method uses a time-domain approach that was dictated by constraints imposed by the partial overlap of fast and slow waves. The second method uses a frequency-domain log-spectral subtraction technique on the separated fast and slow waves. Applying the time-domain analysis to the broadband data yields apparent attenuation behavior that is larger in the early stages of propagation and decreases as the wave travels deeper. In contrast, performing frequency-domain analysis on the separated fast waves and slow waves results in attenuation coefficients that are independent of propagation distance. Results suggest that features arising from the analysis of overlapping two-mode data may represent an alternate explanation for the previously reported apparent dependence on propagation distance of the attenuation coefficient of cancellous bone.

  12. Ankaflavin: a natural novel PPARγ agonist upregulates Nrf2 to attenuate methylglyoxal-induced diabetes in vivo.

    PubMed

    Lee, Bao-Hong; Hsu, Wei-Hsuan; Chang, Yu-Ying; Kuo, Hsuan-Fu; Hsu, Ya-Wen; Pan, Tzu-Ming

    2012-12-01

    , we believe that GSH may lower the MG level, which attenuates the formation of AGEs in the serum, kidney, liver, and pancreas of MG-induced rats. We also found that AK treatment reduced the production of inflammatory factors, such as tumor necrosis factor-α and interleukin-1β. Taken together, the results of our mechanistic study of MG-induced rats suggest that the protective effects of AK against diabetes are mediated by the upregulation of the signaling pathway of Nrf2, which enhances antioxidant activity and serves as a PPARγ agonist to enhance insulin sensitivity.

  13. Treatment with resveratrol attenuates sublesional bone loss in spinal cord-injured rats

    PubMed Central

    Wang, Hua-Dong; Shi, Ya-Min; Li, Li; Guo, Ji-Dong; Zhang, Yu-Peng; Hou, Shu-Xun

    2013-01-01

    BACKGROUND AND PURPOSE Sublesional osteoporosis predisposes individuals with spinal cord injury (SCI) to an increased risk of low-trauma fracture. The aim of the present work was to investigate the effect of treatment with resveratrol (RES) on sublesional bone loss in spinal cord-injured rats. EXPERIMENTAL APPROACH Complete SCI was generated by surgical transaction of the cord at the T10–12 level. Treatment with RES (400 mg·kg−1 body mass per day−1, intragastrically) was initiated 12 h after the surgery for 10 days. Then, blood was collected and femurs and tibiae were removed for evaluation of the effects of RES on bone tissue after SCI. KEY RESULTS Treatment of SCI rats with RES prevented the reduction of bone mass including bone mineral content and bone mineral density in tibiae, preserved bone structure including trabecular bone volume fraction, trabecular number, and trabecular thickness in tibiae, and preserved mechanical strength including ultimate load, stiffness, and energy in femurs. Treatment of SCI rats with RES enhanced femoral total sulfhydryl content, reduced femoral malondialdehyde and IL-6 mRNA levels. Treatment of SCI rats with RES suppressed the up-regulation of mRNA levels of PPARγ, adipose-specific fatty-acid-binding protein and lipoprotein lipase, and restored mRNA levels of Wnt1, low-density lipoprotein-related protein 5, Axin2, ctnnb1, insulin-like growth factor 1 (IGF-1) and receptor for IGF-1 in femurs and tibiae. CONCLUSIONS AND IMPLICATIONS Treatment with RES attenuated sublesional bone loss in spinal-cord-injured rats, associated with abating oxidative stress, attenuating inflammation, depressing PPARγ signalling, and restoring Wnt/β-catenin and IGF-1 signalling. PMID:23848300

  14. Bone Density in Adolescents Treated with a GnRH Agonist and Add-Back Therapy for Endometriosis

    PubMed Central

    DiVasta, Amy D.; Laufer, Marc R.; Gordon, Catherine M.

    2011-01-01

    Study Objective To evaluate the bone density of adolescents with endometriosis treated with a GnRH-agonist and “add-back” therapy with norethindrone acetate. Design Retrospective chart review. Setting Pediatric gynecology clinic at a tertiary care center. Participants 36 adolescents, ages 13 to 21 years, with endometriosis. Main Outcome Measures Bone mineral density (BMD, g/cm2) by dual energy x-ray absorptiometry (DXA); BMD Z-scores of hip and spine. Results The mean BMD Z-score at the total hip was −0.24 ± 1.0, with a range of −2.4 to 1.7. At this site, 6 subjects had a BMD Z-score between −1.0 and −2.0 SD, while 2 had a Z-score ≤ −2.0 SD. The mean BMD Z-score at the lumbar spine was 0.55 ± 1.1, with a range of −2.8 to 1.4. At the spine, 11 subjects had a BMD Z-score between −1.0 and −2.0 SD, while 3 had a Z-score ≤ −2.0 SD. There was no correlation noted between duration of therapy with the GnRH-agonist plus add-back and BMD at the hip or spine. Conclusion BMD at the hip was normal in most adolescents with endometriosis who were receiving a GnRH-agonist plus add-back therapy with norethindrone acetate. Almost one third of subjects exhibited skeletal deficits at the spine. These data suggest that BMD should be carefully monitored in adolescents receiving treatment with GnRH agonists. PMID:17868896

  15. Bone density in adolescents treated with a GnRH agonist and add-back therapy for endometriosis.

    PubMed

    Divasta, Amy D; Laufer, Marc R; Gordon, Catherine M

    2007-10-01

    To evaluate the bone density of adolescents with endometriosis treated with a GnRH-agonist and "add-back" therapy with norethindrone acetate. Retrospective chart review. Pediatric gynecology clinic at a tertiary care center. 36 adolescents, ages 13 to 21 years, with endometriosis. Bone mineral density (BMD, g/cm(2)) by dual energy x-ray absorptiometry (DXA); BMD Z-scores of hip and spine. The mean BMD Z-score at the total hip was -0.24 +/- 1.0, with a range of -2.4 to 1.7. At this site, 6 subjects had a BMD Z-score between -1.0 and -2.0 SD, while 2 had a Z-score < or = -2.0 SD. The mean BMD Z-score at the lumbar spine was 0.55 +/- 1.1, with a range of -2.8 to 1.4. At the spine, 11 subjects had a BMD Z-score between -1.0 and -2.0 SD, while 3 had a Z-score < or = -2.0 SD. There was no correlation noted between duration of therapy with the GnRH-agonist plus add-back and BMD at the hip or spine. BMD at the hip was normal in most adolescents with endometriosis who were receiving a GnRH-agonist plus add-back therapy with norethindrone acetate. Almost one third of subjects exhibited skeletal deficits at the spine. These data suggest that BMD should be carefully monitored in adolescents receiving treatment with GnRH agonists.

  16. Anthropometric and fitness variables associated with bone mineral density and broadband ultrasound attenuation in ambulatory children with cerebral palsy.

    PubMed

    Chen, Chia-ling; Ke, Jyh-yuh; Lin, Keh-chung; Wang, Chao-jan; Wu, Ching-yi; Liu, Wen-yu

    2011-05-01

    We investigated anthropometric and fitness variables associated with areal bone mineral densities and broadband ultrasound attenuation in ambulatory children with cerebral palsy. Thirty-four children with cerebral palsy, aged 4-12 years, and 33 normal development children were collected. There were significant differences in femoral bone densities and calcaneus broadband ultrasound attenuation, but not in lumbar bone densities, between cerebral palsy and normal groups. Regression analysis revealed that different anthropometric and fitness variables were linked to bone densities of different skeletal regions in children with cerebral palsy (adjusted r(2) = .41-.67). Growth variables were mainly related to femoral and lumbar bone densities, while muscular endurance was mainly related to femoral and calcaneus bone densities. These findings suggest multiple complex variables can contribute to bone density variations among different skeleton areas in these children. These data can allow clinicians to identifying early these children at risk for low bone density.

  17. Secreted frizzled-related protein 1 modulates glucocorticoid attenuation of osteogenic activities and bone mass.

    PubMed

    Wang, Feng-Sheng; Lin, Chun-Liang; Chen, Yeung-Jen; Wang, Ching-Jen; Yang, Kuender D; Huang, Yu-Ting; Sun, Yi-Chih; Huang, Hui-Chen

    2005-05-01

    Prolonged glucocorticoid treatment is known to cause osteoporosis or aseptic necrosis. Secreted frizzled-related proteins 1 (SFRP1) and low-density lipoprotein-related protein 5 (LRP5), a Wnt protein antagonist and a coreceptor, have been found to regulate skeletogenesis. Whereas recent studies have reported that excess glucocorticoid promotes bone loss, the biological role of SFRP1 and LRP5 in regulating glucocorticoid attenuation of bone formation is not fully understood. We showed that a supraphysiological level of glucocorticoid enhanced SFRP1 but not LRP5 expression of primary mesenchymal cell cultures in vitro and osteoblasts at metaphyseal trabecular endosteum and chondrocytes at calcified cartilage in vivo. Glucocorticoid augmentation of SFRP1 expression was transcriptionally mediated. The inhibitory action of glucocorticoid on osteogenic differentiation appeared to be regulated by SFRP1 mediation of beta-catenin destabilization because knocking down SFRP1 by RNA interference abrogated the supraphysiological level of glucocorticoid attenuation of osteogenesis. Recombinant human SFRP1 reduced the promoting effect of physiological level of glucocorticoid on cytosolic beta-catenin accumulation, runt-related transcription factor-2 activation, and osteogenic activities. Glucocorticoid and recombinant human SFRP1 significantly increased osteochondral cell apoptosis associated with reduced mineral density, biomechanical properties, trabecular bone volume, and midshaft cortical bone areas in rat femurs. These findings suggest that SFRP1 modulates glucocorticoid-induced bone loss. Regulation of Wnt/SFRP signal transduction can be used in the future as an alternative strategy for the prevention of glucocorticoid-induced osteoporosis.

  18. Analysis of gait in rats with olivocerebellar lesions and ability of the nicotinic acetylcholine receptor agonist varenicline to attenuate impairments

    PubMed Central

    Lambert, C. S.; Philpot, R. M.; Engberg, M. E.; Johns, B. E.; Wecker, L.

    2015-01-01

    Studies have demonstrated that administration of the neuronal nicotinic receptor agonist varenicline to rats with olivocerebellar lesions attenuates balance deficits on a rotorod and balance beam, but the effects of this drug on gait deficits have not been investigated. To accomplish this, male Sprague-Dawley rats were trained to walk on a motorized treadmill at 25 and 35 cm/s and baseline performance determined; both temporal and spatial gait parameters were analyzed. A principal component analysis (PCA) was used to identify the key components of gait, and the cumulative gait index (CGI) was calculated, representing deviations from prototypical gait patterns. Subsequently, animals either remained as non-lesioned controls or received injections of 3-acetylpyridine (3-AP)/nicotinamide to destroy the climbing fibers innervating Purkinje cells. The gait of the non-lesioned group was assessed weekly to monitor changes in the normal population, while the gait of the lesioned group was assessed 1 week following 3-AP administration, and weekly following the daily administration of saline or varenicline (0.3, 1.0, or 3.0 mg free base/kg) for 2 weeks. Non-lesioned animals exhibited a 60–70% increased CGI over time due to increases in temporal gait measures, whereas lesioned animals exhibited a nearly 3-fold increased CGI as a consequence of increases in spatial measures. Following 2 weeks of treatment with the highest dose of varenicline (3.0 mg free base/kg), the swing duration of lesioned animals normalized, and stride duration, stride length and step angle in this population did not differ from the non-lesioned population. Thus, varenicline enabled animals to compensate for their impairments and rectify the timing of the gait cycle. PMID:26049061

  19. A dopamine receptor d2-type agonist attenuates the ability of stress to alter sleep in mice.

    PubMed

    Jefferson, F; Ehlen, J C; Williams, N S; Montemarano, J J; Paul, K N

    2014-11-01

    Although sleep disruptions that accompany stress reduce quality of life and deteriorate health, the mechanisms through which stress alters sleep remain obscure. Psychological stress can alter sleep in a variety of ways, but it has been shown to be particularly influential on rapid eye movement (REM) sleep. Prolactin (PRL), a sexually dimorphic, stress-sensitive hormone whose basal levels are higher in females, has somnogenic effects on REM sleep. In the current study, we examined the relationship between PRL secretion and REM sleep after restraint stress to determine whether: 1) the ability of stress to increase REM sleep is PRL-dependent, and 2) fluctuating PRL levels underlie sex differences in sleep responses to stress. Because dopamine D2 receptors in the pituitary gland are the primary regulator of PRL secretion, D2 receptor agonist, 1-[(6-allylergolin-8β-yl)-carbonyl]-1-[3-(dimethylamino) propyl]-3-ethylurea (cabergoline), was used to attenuate PRL levels in mice before 1 hour of restraint stress. Mice were implanted with electroencephalographic/electromyographic recording electrodes and received an ip injection of either 0.3-mg/kg cabergoline or vehicle before a control procedure of 1 hour of sleep deprivation by gentle handling during the light phase. Six days after the control procedure, mice received cabergoline or vehicle 15 minutes before 1 hour of restraint stress. Cabergoline blocked the ability of restraint stress to increase REM sleep amount in males but did not alter REM sleep amount after stress in females even though it reduced basal REM sleep amount in female controls. These data provide evidence that the ability for restraint stress to increase REM sleep is dependent on PRL and that sex differences in REM sleep amount may be driven by PRL.

  20. Agonists of MAS oncogene and angiotensin II type 2 receptors attenuate cardiopulmonary disease in rats with neonatal hyperoxia-induced lung injury.

    PubMed

    Wagenaar, Gerry T M; Laghmani, El Houari; Fidder, Melissa; Sengers, Rozemarijn M A; de Visser, Yvonne P; de Vries, Louwe; Rink, Rick; Roks, Anton J M; Folkerts, Gert; Walther, Frans J

    2013-09-01

    Stimulation of MAS oncogene receptor (MAS) or angiotensin (Ang) receptor type 2 (AT2) may be novel therapeutic options for neonatal chronic lung disease (CLD) by counterbalancing the adverse effects of the potent vasoconstrictor angiotensin II, consisting of arterial hypertension (PAH)-induced right ventricular hypertrophy (RVH) and pulmonary inflammation. We determined the cardiopulmonary effects in neonatal rats with CLD of daily treatment during continuous exposure to 100% oxygen for 10 days with specific ligands for MAS [cyclic Ang-(1-7); 10-50 μg·kg(-1)·day(-1)] and AT2 [dKcAng-(1-7); 5-20 μg·kg(-1)·day(-1)]. Parameters investigated included lung and heart histopathology, fibrin deposition, vascular leakage, and differential mRNA expression in the lungs of key genes involved in the renin-angiotensin system, inflammation, coagulation, and alveolar development. We investigated the role of nitric oxide synthase inhibition with N(ω)-nitro-l-arginine methyl ester (25 mg·kg(-1)·day(-1)) during AT2 agonist treatment. Prophylactic treatment with agonists for MAS or AT2 for 10 days diminished cardiopulmonary injury by reducing alveolar septum thickness and medial wall thickness of small arterioles and preventing RVH. Both agonists attenuated the pulmonary influx of inflammatory cells, including macrophages (via AT2) and neutrophils (via MAS) but did not reduce alveolar enlargement and vascular alveolar leakage. The AT2 agonist attenuated hyperoxia-induced fibrin deposition. In conclusion, stimulation of MAS or AT2 attenuates cardiopulmonary injury by reducing pulmonary inflammation and preventing PAH-induced RVH but does not affect alveolar and vascular development in neonatal rats with experimental CLD. The beneficial effects of AT2 activation on experimental CLD were mediated via a NOS-independent mechanism.

  1. Beneficial effects of a N-terminally modified GIP agonist on tissue-level bone material properties.

    PubMed

    Mabilleau, Guillaume; Mieczkowska, Aleksandra; Irwin, Nigel; Simon, Yannick; Audran, Maurice; Flatt, Peter R; Chappard, Daniel

    2014-06-01

    Bone remodeling is under complex regulation from nervous, hormonal and local signals, including gut hormones. Among the gut hormones, a role for the glucose-dependent insulinotropic polypeptide (GIP) has been suggested. However, the rapid degradation of GIP in the bloodstream by the ubiquitous enzyme dipeptidyl peptidase-4 (DPP-4) precludes therapeutic use. To circumvent this problem, a series of N-terminally modified GIP agonists have been developed, with N-AcGIP being the most promising. The aims of the present study were to investigate the effects of N-AcGIP on bone at the micro-level using trabecular and cortical microstructural morphology, and at the tissue-level in rats. Copenhagen rats were randomly assigned into control or N-AcGIP-treated groups and received daily injection for 4 weeks. Bone microstructural morphology was assessed by microCT and dynamic histomorphometry and tissue-level properties by nanoindentation, qBEI and infra-red microscopy. Four week treatment with N-AcGIP did not alter trabecular or cortical microstructural morphology. In addition, no significant modifications of mechanical response and properties at the tissue-level were observed in trabecular bone. However, significant augmentations in maximum load (12%), hardness (14%), indentation modulus (13%) and dissipated energy (16%) were demonstrated in cortical bone. These beneficial modifications of mechanical properties at the tissue-level were associated with increased mineralization (22%) and collagen maturity (13%) of the bone matrix. Taken together, the results support a beneficial role of GIP, and particularly stable analogs such as N-AcGIP, on tissue material properties of bone.

  2. Attenuation of nicotine's discriminative stimulus effects in rats and its locomotor activity effects in mice by serotonergic 5-HT2A/2C receptor agonists.

    PubMed

    Batman, Angela M; Munzar, Patrik; Beardsley, Patrick M

    2005-05-01

    Reports have indicated that administration of nicotine inhibits, while withdrawal of chronically administered nicotine augments effects of serotonergic 5HT2A/2C agonists. It was our objective to determine whether 5HT2A/2C agonists can modulate the discriminative stimulus effects of nicotine in rats or its locomotor activity effects in mice. Adult male Sprague-Dawley rats were trained to discriminate 0.3 mg/kg nicotine base from saline in a two-lever, fixed-ratio (FR10), food-reinforced, operant-conditioning task during daily (Monday-Friday) 15-min experimental sessions. After characterizing a dose-response curve for nicotine, we tested the ability of the 5HT(2A/2C) agonists (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCL (DOI; 0.18-1.0 mg/kg) and 1-(4-bromo-2, 5-dimethoxyphenyl)-2-aminopropane (DOB; 0.1-1.0 mg/kg), the 5HT2C agonist 6-chloro-2-(1-piperazinyl)pyrazine hydrochloride (MK 212; 0.1 mg/kg-1.0 mg/kg), and the 5HT1A agonist (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT; 0.01 mg/kg-1.0 mg/kg) to modulate nicotine's discriminative stimulus effects. After finding that DOI was able to attenuate the percentage nicotine lever responding (%NLR), we tested for it to also reverse nicotine's effects on locomotor activity in mice. The 5HT2A/2C agonists-in particular DOI-dose dependently attenuated %NLR. The effects of DOI were reversed by the 5HT2A/2C antagonist ketanserin. MK 212 and 8-OH-DPAT had irregular effects among rats and only reduced %NLR to below 50% levels at doses markedly suppressing responding. DOI also dose dependently blocked nicotine's acute rate-lowering locomotor activity effects. These results indicate that activation of serotonin 5HT2A/2C receptors can blunt the discriminative stimulus and locomotor activity effects of nicotine and presents the possibility that activation of these receptors might also be able to attenuate other effects of nicotine.

  3. Opioid receptor agonists may favorably affect bone mechanical properties in rats with estrogen deficiency-induced osteoporosis.

    PubMed

    Janas, Aleksandra; Folwarczna, Joanna

    2017-02-01

    The results of epidemiological, clinical, and in vivo and in vitro experimental studies on the effect of opioid analgesics on bone are inconsistent. The aim of the present study was to investigate the effect of morphine (an agonist of opioid receptors), buprenorphine (a partial μ opioid receptor agonist and κ opioid receptor antagonist), and naloxone (an antagonist of opioid receptors) on the skeletal system of female rats in vivo. The experiments were carried out on 3-month-old Wistar rats, divided into two groups: nonovariectomized (intact; NOVX) rats and ovariectomized (OVX) rats. The bilateral ovariectomy was performed 7 days before the start of drug administration. Morphine hydrochloride (20 mg/kg/day s.c.), buprenorphine (0.05 mg/kg/day s.c.), or naloxone hydrochloride dihydrate (2 mg/kg/day s.c.) were administered for 4 weeks to NOVX and OVX rats. In OVX rats, the use of morphine and buprenorphine counteracted the development of osteoporotic changes in the skeletal system induced by estrogen deficiency. Morphine and buprenorphine beneficially affected also the skeletal system of NOVX rats, but the effects were much weaker than those in OVX rats. Naloxone generally did not affect the rat skeletal system. The results confirmed the role of opioid receptors in the regulation of bone remodeling processes and demonstrated, in experimental conditions, that the use of opioid analgesics at moderate doses may exert beneficial effects on the skeletal system, especially in estrogen deficiency.

  4. Longitudinal follow-up of bone density and body composition in children with precocious or early puberty before, during and after cessation of GnRH agonist therapy.

    PubMed

    van der Sluis, Inge M; Boot, Annemieke M; Krenning, Eric P; Drop, Stenvert L S; de Muinck Keizer-Schrama, Sabine M P F

    2002-02-01

    We studied bone mineral density (BMD), bone metabolism, and body composition in 47 children with central precocious puberty (n = 36) or early puberty (n = 11) before, during, and after cessation of GnRH agonist. Bone density and body composition were measured with dual energy x-ray absorptiometry and expressed as SD scores. Bone age and biochemical parameters of bone turnover were assessed. Measurements were performed at baseline, after 6 months, and on a yearly basis thereafter. Mean lumbar spine BMD SD scores for chronological age were significantly higher than zero at baseline and decreased during treatment. Lumbar spine bone mineral apparent density and total body BMD did not differ from normal at baseline and showed no significant changes during treatment. In contrast, BMD SD scores for bone age were significantly lower than zero at baseline and at cessation of therapy. Two years after therapy, bone mineral apparent density and BMD SD scores for bone age and chronological age did not differ from normal. Markers of bone turnover decreased during treatment, mainly in the first 6 months. Patients had increased percentage of fat and lean body mass at baseline. After an initial increase of percentage body fat during treatment, percentage body fat decreased and normalized within 1 yr after cessation of treatment. Our longitudinal analysis suggests that peak bone mass or body composition will not be impaired in patients with precocious or early puberty after GnRH agonist therapy.

  5. Hearing protection: Surpassing the limits to attenuation imposed by the bone-conduction pathways

    NASA Astrophysics Data System (ADS)

    Berger, Elliott H.; Kieper, Ronald W.; Gauger, Dan

    2003-10-01

    With louder and louder weapon systems being developed and military personnel being exposed to steady noise levels approaching and sometimes exceeding 150 dB, a growing interest in greater amounts of hearing protection is evident. When the need for communications is included in the equation, the situation is even more extreme. New initiatives are underway to design improved hearing protection, including active noise reduction (ANR) earplugs and perhaps even active cancellation of head-borne vibration. With that in mind it may be useful to explore the limits to attenuation, and whether they can be approached with existing technology. Data on the noise reduction achievable with high-attenuation foam earplugs, as a function of insertion depth, will be reported. Previous studies will be reviewed that provide indications of the bone-conduction (BC) limits to attenuation that, in terms of mean values, range from 40 to 60 dB across the frequencies from 125 Hz to 8 kHz. Additionally, new research on the effects of a flight helmet on the BC limits, as well as the potential attenuation from deeply inserted passive foam earplugs, worn with passive earmuffs, or with active-noise reduction (ANR) earmuffs, will be examined. The data demonstrate that gains in attenuation exceeding 10 dB above the head-not-covered limits can be achieved if the head is effectively shielded from acoustical stimulation.

  6. Hearing protection: surpassing the limits to attenuation imposed by the bone-conduction pathways.

    PubMed

    Berger, Elliott H; Kieper, Ronald W; Gauger, Dan

    2003-10-01

    With louder and louder weapon systems being developed and military personnel being exposed to steady noise levels approaching and sometimes exceeding 150 dB, a growing interest in greater amounts of hearing protection is evident. When the need for communications is included in the equation, the situation is even more extreme. New initiatives are underway to design improved hearing protection, including active noise reduction (ANR) earplugs and perhaps even active cancellation of head-borne vibration. With that in mind it may be useful to explore the limits to attenuation, and whether they can be approached with existing technology. Data on the noise reduction achievable with high-attenuation foam earplugs, as a function of insertion depth, will be reported. Previous studies will be reviewed that provide indications of the bone-conduction (BC) limits to attenuation that, in terms of mean values, range from 40 to 60 dB across the frequencies from 125 Hz to 8 kHz. Additionally, new research on the effects of a flight helmet on the BC limits, as well as the potential attenuation from deeply inserted passive foam earplugs, worn with passive earmuffs, or with active-noise reduction (ANR) earmuffs, will be examined. The data demonstrate that gains in attenuation exceeding 10 dB above the head-not-covered limits can be achieved if the head is effectively shielded from acoustical stimulation.

  7. PPARγ antagonist attenuates mouse immune-mediated bone marrow failure by inhibition of T cell function

    PubMed Central

    Sato, Kazuya; Feng, Xingmin; Chen, Jichun; Li, Jungang; Muranski, Pawel; Desierto, Marie J.; Keyvanfar, Keyvan; Malide, Daniela; Kajigaya, Sachiko; Young, Neal S.

    2016-01-01

    Acquired aplastic anemia is an immune-mediated disease, in which T cells target hematopoietic cells; at presentation, the bone marrow is replaced by fat. It was reported that bone marrow adipocytes were negative regulators of hematopoietic microenvironment. To examine the role of adipocytes in bone marrow failure, we investigated peroxisomal proliferator-activated receptor gamma, a key transcription factor in adipogenesis, utilizing an antagonist of this factor called bisphenol-A-diglycidyl-ether. While bisphenol-A-diglycidyl-ether inhibited adipogenesis as expected, it also suppressed T cell infiltration of bone marrow, reduced plasma inflammatory cytokines, decreased expression of multiple inflammasome genes, and ameliorated marrow failure. In vitro, bisphenol-A-diglycidyl-ether suppressed activation and proliferation, and reduced phospholipase C gamma 1 and nuclear factor of activated T-cells 1 expression, as well as inhibiting calcium flux in T cells. The in vivo effect of bisphenol-A-diglycidyl-ether on T cells was confirmed in a second immune-mediated bone marrow failure model, using different strains and non-major histocompatibility antigen mismatched: bisphenol-A-diglycidyl-ether ameliorated marrow failure by inhibition of T cell infiltration of bone marrow. Our data indicate that peroxisomal proliferator-activated receptor gamma antagonists may attenuate murine immune-mediated bone marrow failure, at least in part, by suppression of T cell activation, which might hold implications in the application of peroxisomal proliferator-activated receptor gamma antagonists in immune-mediated pathophysiologies, both in the laboratory and in the clinic. Genetically “fatless” mice developed bone marrow failure with accumulation of marrow adipocytes in our model, even in the absence of body fat, suggesting different mechanisms of systematic and marrow adipogenesis and physiologic versus pathophysiologic fat accumulation. PMID:26589913

  8. PPARγ antagonist attenuates mouse immune-mediated bone marrow failure by inhibition of T cell function.

    PubMed

    Sato, Kazuya; Feng, Xingmin; Chen, Jichun; Li, Jungang; Muranski, Pawel; Desierto, Marie J; Keyvanfar, Keyvan; Malide, Daniela; Kajigaya, Sachiko; Young, Neal S

    2016-01-01

    Acquired aplastic anemia is an immune-mediated disease, in which T cells target hematopoietic cells; at presentation, the bone marrow is replaced by fat. It was reported that bone marrow adipocytes were negative regulators of hematopoietic microenvironment. To examine the role of adipocytes in bone marrow failure, we investigated peroxisomal proliferator-activated receptor gamma, a key transcription factor in adipogenesis, utilizing an antagonist of this factor called bisphenol-A-diglycidyl-ether. While bisphenol-A-diglycidyl-ether inhibited adipogenesis as expected, it also suppressed T cell infiltration of bone marrow, reduced plasma inflammatory cytokines, decreased expression of multiple inflammasome genes, and ameliorated marrow failure. In vitro, bisphenol-A-diglycidyl-ether suppressed activation and proliferation, and reduced phospholipase C gamma 1 and nuclear factor of activated T-cells 1 expression, as well as inhibiting calcium flux in T cells. The in vivo effect of bisphenol-A-diglycidyl-ether on T cells was confirmed in a second immune-mediated bone marrow failure model, using different strains and non-major histocompatibility antigen mismatched: bisphenol-A-diglycidyl-ether ameliorated marrow failure by inhibition of T cell infiltration of bone marrow. Our data indicate that peroxisomal proliferator-activated receptor gamma antagonists may attenuate murine immune-mediated bone marrow failure, at least in part, by suppression of T cell activation, which might hold implications in the application of peroxisomal proliferator-activated receptor gamma antagonists in immune-mediated pathophysiologies, both in the laboratory and in the clinic. Genetically "fatless" mice developed bone marrow failure with accumulation of marrow adipocytes in our model, even in the absence of body fat, suggesting different mechanisms of systematic and marrow adipogenesis and physiologic versus pathophysiologic fat accumulation.

  9. Use of glucagon-like peptide-1 receptor agonists and bone fractures: a meta-analysis of randomized clinical trials.

    PubMed

    Mabilleau, Guillaume; Mieczkowska, Aleksandra; Chappard, Daniel

    2014-05-01

    Patients with type 2 diabetes mellitus (T2DM) are at a higher risk of bone fractures independent of the use of antidiabetic medications. Furthermore, antidiabetic medications could directly affect bone metabolism. Recently, the use of dipeptidyl peptidase-4 inhibitors has been associated with a lower rate of bone fracture. The aim of the present meta-analysis was to assess whether patients with T2DM treated with glucagon-like peptide-1 receptor agonists (GLP-1Ra) present a lower incidence of bone fracture compared with patients using other antidiabetic drugs. A search on Medline, Embase, and http://www.clinicaltrials.gov, as well as a manual search for randomized clinical trials of T2DM treated with either a GLP-1Ra or another antidiabetic drug for a duration of ≥24 weeks was conducted by two authors (GM, AM) independently. Although 28 eligible studies were identified, only seven trials reported the occurrence of at least a bone fracture in one arm of the trial. The total number of fractures was 19 (13 and six with GLP-1Ra and comparator, respectively). The pooled Mantel-Haenszel odds ratio for GLP-1Ra was 0.75 (95% confidence interval 0.28-2.02, P = 0.569) in trials versus other antidiabetic agents. Although preliminary, our study highlighted that the use of GLP-1Ra does not modify the risk of bone fracture in T2DM compared with the use of other antidiabetic medications. © 2013 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

  10. Inhibition of TGF–β signaling in subchondral bone mesenchymal stem cells attenuates osteoarthritis

    PubMed Central

    Zhen, Gehua; Wen, Chunyi; Jia, Xiaofeng; Li, Yu; Crane, Janet L.; Mears, Simon C.; Askin, Frederic B.; Frassica, Frank J.; Chang, Weizhong; Yao, Jie; Nayfeh, Tariq; Johnson, Carl; Artemov, Dmitri; Chen, Qianming; Zhao, Zhihe; Zhou, Xuedong; Cosgarea, Andrew; Carrino, John; Riley, Lee; Sponseller, Paul; Wan, Mei; Lu, William Weijia; Cao, Xu

    2013-01-01

    Osteoarthritis is a highly prevalent and debilitating joint disorder. There is no effective medical therapy for osteoarthritis due to limited understanding of osteoarthritis pathogenesis. We show that TGF–β1 is activated in the subchondral bone in response to altered mechanical loading in an anterior cruciate ligament transection (ACLT) osteoarthritis mouse model. TGF–β1 concentrations also increased in human osteoarthritis subchondral bone. High concentrations of TGF–β1 induced formation of nestin+ mesenchymal stem cell (MSC) clusters leading to aberrant bone formation accompanied by increased angiogenesis. Transgenic expression of active TGF–β1 in osteoblastic cells induced osteoarthritis. Inhibition of TGF–β activity in subchondral bone attenuated degeneration of osteoarthritis articular cartilage. Notably, knockout of the TGF–β type II receptor (TβRII) in nestin+ MSCs reduced development of osteoarthritis in ACLT mice. Thus, high concentrations of active TGF–β1 in the subchondral bone initiated the pathological changes of osteoarthritis, inhibition of which could be a potential therapeutic approach. PMID:23685840

  11. Investigation of the influence of reflection on the attenuation of cancellous bone.

    PubMed

    Klinge, Sandra; Hackl, Klaus; Gilbert, Robert P

    2013-01-01

    The model proposed in this paper is based on the fact that the reflection might have a significant contribution to the attenuation of the acoustic waves propagating through the cancellous bone. The numerical implementation of the mentioned effect is realized by the development of a new representative volume element that includes an infinitesimally thin 'transient' layer on the contact surface of the bone and the marrow. This layer serves to model the amplitude transformation of the incident wave by the transition through media with different acoustic impedances and to take into account the energy loss due to the reflection. The proposed representative volume element together with the multiscale finite element is used to simulate the wave propagation and to evaluate the attenuation coefficient for samples with different effective densities in the dependence of the applied excitation frequency. The obtained numerical values show a very good agreement with the experimental results. Moreover, the model enables the determination of the upper and the lower bound for the attenuation coefficient.

  12. Oncolytic virotherapy for human bone and soft tissue sarcomas using live attenuated poliovirus.

    PubMed

    Atsumi, Satoru; Matsumine, Akihiko; Toyoda, Hidemi; Niimi, Rui; Iino, Takahiro; Nakamura, Tomoki; Matsubara, Takao; Asanuma, Kunihiro; Komada, Yoshihiro; Uchida, Atsumasa; Sudo, Akihiro

    2012-09-01

    The poliovirus receptor CD155, is essential for poliovirus to infect and induce death in neural cells. Recently, CD155 has been shown to be selectively expressed on certain types of tumor cells originating from the neural crest, including malignant glioma and neuroblastoma. However, the expression pattern of CD155 in soft tissue sarcoma has not been examined. Therefore, we first examined CD155 expression in sarcoma cell lines, and found the expression of both CD155 mRNA and protein in 12 soft and bone tissue sarcoma cell lines. Furthermore, we examined the effect of live attenuated poliovirus (LAPV) on 6 bone and soft tissue sarcoma cell lines in vitro, and found that LAPV induced apoptosis by activating caspases 7 and 3 in all of these cell lines. Furthermore, in BALB/c nu/nu mice xenotransplanted with HT1080 fibrosarcoma cells, administration of live attenuated poliovirus caused growth suppression of the tumors. These results suggest that oncolytic therapy using a LAPV may represent a new option for the treatment of bone and soft tissue sarcomas.

  13. Attenuated Human Bone Morphogenetic Protein-2–Mediated Bone Regeneration in a Rat Model of Composite Bone and Muscle Injury

    PubMed Central

    Li, Mon-Tzu A.; Uhrig, Brent A.; Boerckel, Joel David; Huebsch, Nathaniel; Lundgren, Taran L.; Warren, Gordon L.; Guldberg, Robert E.

    2013-01-01

    Extremity injuries involving large bone defects with concomitant severe muscle damage are a significant clinical challenge often requiring multiple treatment procedures and possible amputation. Even if limb salvage is achieved, patients are typically left with severe short- and long-term disabilities. Current preclinical animal models do not adequately mimic the severity, complexity, and loss of limb function characteristic of these composite injuries. The objectives of this study were to establish a composite injury model that combines a critically sized segmental bone defect with an adjacent volumetric muscle loss injury, and then use this model to quantitatively assess human bone morphogenetic protein-2 (rhBMP-2)–mediated tissue regeneration and restoration of limb function. Surgeries were performed on rats in three experimental groups: muscle injury (8-mm-diameter full-thickness defect in the quadriceps), bone injury (8-mm nonhealing defect in the femur), or composite injury combining the bone and muscle defects. Bone defects were treated with 2 μg of rhBMP-2 delivered in the pregelled alginate injected into a cylindrical perforated nanofiber mesh. Bone regeneration was quantitatively assessed using microcomputed tomography, and limb function was assessed using gait analysis and muscle strength measurements. At 12 weeks postsurgery, treated bone defects without volumetric muscle loss were consistently bridged. In contrast, the volume and mechanical strength of regenerated bone were attenuated by 45% and 58%, respectively, in the identically treated composite injury group. At the same time point, normalized muscle strength was reduced by 51% in the composite injury group compared to either single injury group. At 2 weeks, the gait function was impaired in all injury groups compared to baseline with the composite injury group displaying the greatest functional deficit. We conclude that sustained delivery of rhBMP-2 at a dose sufficient to induce bridging of

  14. Alpha 2A adrenergic receptor agonist, guanfacine, attenuates cocaine-related impairments of inhibitory response control and working memory in animal models.

    PubMed

    Terry, Alvin V; Callahan, Patrick M; Schade, Rosann; Kille, Nancy J; Plagenhoef, Marc

    2014-11-01

    There is considerable evidence that centrally acting α2A adrenergic receptor agonists can attenuate impairments in executive function that result from dysfunction of the prefrontal cortex. Such positive effects resulted in the recent approval by the United States Food and Drug Administration (FDA) of the α2A agonists clonidine and guanfacine for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD), but also suggest that they could have beneficial effects in substance abuse disorders and other neuropsychiatric conditions. The purpose of this study was to evaluate guanfacine for its ability to attenuate behavioral alterations associated with acute cocaine exposure in rats trained to perform a task of sustained attention, the five choice serial reaction time task (5C-SRTT) and monkeys trained to perform a task of working/short term memory, the delayed match to sample (DMTS) task. In the rodent 5C-SRTT acute intraperitoneal (i.p.) administration of cocaine (3.5-15.0mg/kg) did not affect accuracy, but was associated with dose-dependent increases in premature responses and timeout responses. Guanfacine (0.1-1.0mg/kgi.p.) dose-dependently decreased premature responses and timeout responses associated with cocaine and it attenuated similar deficits in inhibitory response control observed in a variable ITI version of the 5C-SRTT. In the DMTS task in monkeys, acute intramuscular (i.m.) administration of cocaine (4.0mg/kg) was associated with impairments in accuracy at long delay intervals, an effect that was attenuated by guanfacine (0.4mg/kg). These animal studies suggest that guanfacine may have therapeutic potential for treating impairments of executive function that are associated with the abuse of cocaine. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Alpha 2A adrenergic receptor agonist, guanfacine, attenuates cocaine-related impairments of inhibitory response control and working memory in animal models

    PubMed Central

    Terry, Alvin V.; Callahan, Patrick M.; Schade, Rosann; Kille, Nancy J.; Plagenhoef, Marc

    2014-01-01

    There is considerable evidence that centrally acting α2A adrenergic receptor agonists can attenuate impairments in executive function that result from dysfunction of the prefrontal cortex. Such positive effects resulted in the recent approval by the United States Food and Drug Administration (FDA) of the α2A agonists clonidine and guanfacine for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD), but also suggest that they could have beneficial effects in substance abuse disorders and other neuropsychiatric conditions. The purpose of this study was to evaluate guanfacine for its ability to attenuate behavioral alterations associated with acute cocaine exposure in rats trained to perform a task of sustained attention, the five choice serial reaction time task (5C-SRTT) and monkeys trained to perform a task of working/short term memory, the delayed match to sample task (DMTS). In the rodent 5C-SRTT acute intraperitoneal (i.p.) administration of cocaine (3.5–15.0 mg/kg) did not affect accuracy, but was associated with dose-dependent increases in premature responses and timeout responses. Guanfacine (0.1–1.0 mg/kg i.p.) dose-dependently decreased premature responses and timeout responses associated with cocaine and it attenuated similar deficits in inhibitory response control observed in a variable ITI version of the 5C-SRTT. In the DMTS task in monkeys, acute intramuscular (i.m.) administration of cocaine (4.0 mg/kg) was associated with impairments in accuracy at long delay intervals, an effect that was attenuated by guanfacine (0.4 mg/kg). These animal studies suggest that guanfacine may have therapeutic potential for treating impairments of executive function that are associated with the abuse of cocaine. PMID:25242808

  16. Human bone marrow mesenchymal stem cell transplantation attenuates axonal injury in stroke rats

    PubMed Central

    Xu, Yi; Du, Shiwei; Yu, Xinguang; Han, Xiao; Hou, Jincai; Guo, Hao

    2014-01-01

    Previous studies have shown that transplantation of human bone marrow mesenchymal stem cells promotes neural functional recovery after stroke, but the neurorestorative mechanisms remain largely unknown. We hypothesized that functional recovery of myelinated axons may be one of underlying mechanisms. In this study, an ischemia/reperfusion rat model was established using the middle cerebral artery occlusion method. Rats were used to test the hypothesis that intravenous transplantation of human bone marrow mesenchymal stem cells through the femoral vein could exert neuroprotective effects against cerebral ischemia via a mechanism associated with the ability to attenuate axonal injury. The results of behavioral tests, infarction volume analysis and immunohistochemistry showed that cerebral ischemia caused severe damage to the myelin sheath and axons. After rats were intravenously transplanted with human bone marrow mesenchymal stem cells, the levels of axon and myelin sheath-related proteins, including microtubule-associated protein 2, myelin basic protein, and growth-associated protein 43, were elevated, infarct volume was decreased and neural function was improved in cerebral ischemic rats. These findings suggest that intravenously transplanted human bone marrow mesenchymal stem cells promote neural function. Possible mechanisms underlying these beneficial effects include resistance to demyelination after cerebral ischemia, prevention of axonal degeneration, and promotion of axonal regeneration. PMID:25657721

  17. Mas-Related Gene (Mrg) C Activation Attenuates Bone Cancer Pain via Modulating Gi and NR2B.

    PubMed

    Sun, Yu'e; Jiang, Ming; Hou, Bailing; Lu, Cui'e; Lei, Yishan; Ma, Zhengliang; Gu, Xiaoping

    2016-01-01

    This study is to investigate the role of Mas-related gene (Mrg) C in the pathogenesis and treatment of bone cancer pain (BCP). BCP mouse model was established by osteosarcoma cell inoculation. Pain-related behaviors were assessed with the spontaneous lifting behavior test and mechanical allodynia test. Expression levels of MrgC, Gi, and NR2B in the spinal cord were detected with Western blot analysis and immunohistochemistry. Pain-related behavior tests showed significantly increased spontaneous flinches (NSF) and decreased paw withdrawal mechanical threshold (PWMT) in mouse models of BCP. Western blot analysis showed that, compared with the control group and before modeling, all the expression levels of MrgC, Gi, and NR2B in the spinal cord of BCP mice were dramatically elevated, which were especially increased at day 7 after operation and thereafter, in a time-dependent manner. Moreover, the treatment of MrgC agonist BAM8-22 significantly up-regulated Gi and down-regulated NR2B expression levels, in the spinal cord of BCP mice, in a time-dependent manner. On the other hand, anti-MrgC significantly down-regulated Gi expression, while dramatically up-regulated NR2B expression, in the BCP mice. Similar results were obtained from the immunohistochemical detection. Importantly, BAM8-22 significantly attenuated the nociceptive behaviors in the BCP mice. Our results indicated the MrgC-mediated Gi and NR2B expression alterations in the BCP mice, which might contribute to the pain hypersensitivity. These findings may provide a novel strategy for the treatment of BCP in clinic.

  18. Mas-Related Gene (Mrg) C Activation Attenuates Bone Cancer Pain via Modulating Gi and NR2B

    PubMed Central

    Lu, Cui’e; Lei, Yishan; Ma, Zhengliang; Gu, Xiaoping

    2016-01-01

    Objective This study is to investigate the role of Mas-related gene (Mrg) C in the pathogenesis and treatment of bone cancer pain (BCP). Methods BCP mouse model was established by osteosarcoma cell inoculation. Pain-related behaviors were assessed with the spontaneous lifting behavior test and mechanical allodynia test. Expression levels of MrgC, Gi, and NR2B in the spinal cord were detected with Western blot analysis and immunohistochemistry. Results Pain-related behavior tests showed significantly increased spontaneous flinches (NSF) and decreased paw withdrawal mechanical threshold (PWMT) in mouse models of BCP. Western blot analysis showed that, compared with the control group and before modeling, all the expression levels of MrgC, Gi, and NR2B in the spinal cord of BCP mice were dramatically elevated, which were especially increased at day 7 after operation and thereafter, in a time-dependent manner. Moreover, the treatment of MrgC agonist BAM8-22 significantly up-regulated Gi and down-regulated NR2B expression levels, in the spinal cord of BCP mice, in a time-dependent manner. On the other hand, anti-MrgC significantly down-regulated Gi expression, while dramatically up-regulated NR2B expression, in the BCP mice. Similar results were obtained from the immunohistochemical detection. Importantly, BAM8-22 significantly attenuated the nociceptive behaviors in the BCP mice. Conclusion Our results indicated the MrgC-mediated Gi and NR2B expression alterations in the BCP mice, which might contribute to the pain hypersensitivity. These findings may provide a novel strategy for the treatment of BCP in clinic. PMID:27152740

  19. Central Infusion of Angiotensin II Type 2 Receptor Agonist Compound 21 Attenuates DOCA/NaCl-Induced Hypertension in Female Rats

    PubMed Central

    Dai, Shu-Yan; Zhang, Yu-Ping; Peng, Wei; Shen, Ying; He, Jing-Jing

    2016-01-01

    The present study investigated whether central activation of angiotensin II type 2 receptor (AT2-R) attenuates deoxycorticosterone acetate (DOCA)/NaCl-induced hypertension in intact and ovariectomized (OVX) female rats and whether female sex hormone status has influence on the effects of AT2-R activation. DOCA/NaCl elicited a greater increase in blood pressure in OVX females than that in intact females. Central infusion of compound 21, a specific AT2-R agonist, abolished DOCA/NaCl pressor effect in intact females, whereas same treatment in OVX females produced an inhibitory effect. Real-time RT-PCR analysis revealed that DOCA/NaCl enhanced the mRNA expression of hypertensive components including AT1-R, ACE-1, and TNF-α in the paraventricular nucleus of hypothalamus in both intact and OVX females. However, the mRNA expressions of antihypertensive components such as AT2-R, ACE-2, and IL-10 were increased only in intact females. Central AT2-R agonist reversed the changes in the hypertensive components in all females, while this agonist further upregulated the expression of ACE2 and IL-10 in intact females, but only IL-10 in OVX females. These results indicate that brain AT2-R activation plays an inhibitory role in the development of DOCA/NaCl-induced hypertension in females. This beneficial effect of AT2-R activation involves regulation of renin-angiotensin system and proinflammatory cytokines. PMID:26783414

  20. Administration of bone marrow stromal cells in sepsis attenuates sepsis-related coagulopathy.

    PubMed

    Tan, Lifei; Huang, Yueyue; Pan, Xiaojun; Quan, Shichao; Xu, Shunyao; Li, Dequan; Song, Lijun; Zhang, Xiaomin; Chen, Wanzhou; Pan, Jingye

    2016-01-01

    Coagulopathy plays an important role in sepsis. The aim of this study was to determine whether bone marrow stromal cell (BMSC) administration could attenuate coagulopathy in sepsis. In vitro: endothelial cells were cultured with/without BMSCs for 6 h following LPS stimulation and were collected for thrombomodulin (TM) and endothelial protein C receptor (EPCR) measurements. In vivo: Thirty-six mice were randomized into sham, sepsis, and sepsis + BMSC groups (n = 12 each group). Sepsis was induced through cecal ligation and puncture (CLP). BMSC infusion was started at 6 h after CLP. Lung tissues and plasma samples were collected at 24 h after CLP for enzyme-linked immunosorbent assay (ELISA), quantitative real-time RT-PCR, western blot, and immunohistochemistry analysis. In vitro: BMSCs attenuated the decrease in TM and EPCR mRNA and protein expression levels in LPS-stimulated endothelial cells. In vivo: BMSC treatment decreased lung injury and mesenteric perfusion impairment, and ameliorated coagulopathy, as suggested by the reduction in elevated TF, vWF, and TAT circulation levels. BMSC infusion decreased TF mRNA transcription and protein expression levels in lung tissues, and increased TM and EPCR mRNA transcription and expression levels. BMSC administration attenuated coagulopathy, and decreased lung injury and mesenteric perfusion impairment in sepsis. Key messages BMSCs increased the expression of TM and EPCR from endothelium cells exposed to LPS in vitro. BMSC treatment attenuated lung injury and coagulopathy in the mice cecal ligation and puncture (CLP) model. BMSC administration-attenuated coagulopathy is related to the reduced expression of TF and increased expression of TM and EPCR.

  1. The GABA(B) antagonist CGP 52432 attenuates the stimulatory effect of the GABA(B) agonist SKF 97541 on luteinizing hormone secretion in the male sheep.

    PubMed

    Jackson, Gary L; Kuehl, David

    2002-05-01

    The objectives of this study were to determine if the gamma-aminobutyric acid (GABA)(B) agonist, 3-aminopropyl (methyl) phosphinic acid (SKF97541), would increase luteinizing hormone (LH) secretion when infused by microdialysis into the medial basal hypothalamus (MBH) of the castrated ram, and to determine if the action of SKF97541 would be attenuated by co-infusion of the GABA(B) antagonist CGP52432. Initial experiments established that infusion of SKF alone, at concentrations as low as 5 microM, increased mean LH, LH pulse amplitude, and in some cases, pulse interval. In the last experiment, animals were treated with artificial cerebrospinal fluid (CSF) alone, SKF alone (30 microM), 3-[[(3, 4-dichlorophenol) methyl] amino] propyl] diethoxymethyl) phosphinic acid (CGP) alone (500 microM), or SKF plus CGP. SKF increased both mean LH and LH pulse amplitude as compared with CSF. CGP alone had no significant effect on LH, but it attenuated the effect of SKF on mean LH. These observations indicate that the stimulatory effects of GABA(B) agonists on LH pulse patterns are mediated through GABA(B) receptors and provide further evidence that GABA(B) receptors located in the MBH can regulate pulsatile GnRH-LH release.

  2. NO synthase inhibition attenuates EDHF-mediated relaxation induced by TRPV4 channel agonist GSK1016790A in the rat pulmonary artery: Role of TxA2.

    PubMed

    Addison, M Pule; Singh, Thakur Uttam; Parida, Subhashree; Choudhury, Soumen; Kasa, Jaya Kiran; Sukumaran, Susanth V; Darzi, Sajad Ahmad; Kandasamy, Kannan; Singh, Vishakha; Kumar, Dinesh; Mishra, Santosh Kumar

    2016-06-01

    The aim of the present study was to observe the concomitant activation of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) pathways by TRPV4 channel agonist GSK1016790A in the rat pulmonary artery and explore the mechanism by which NO synthase inhibition attenuates EDHF-mediated relaxation in endothelium-intact rat pulmonary artery. Tension experiments were conducted on the pulmonary artery from male Wistar rats. TRPV4 channel agonist GSK1016790A (GSK) caused concentration-dependent relaxation (Emax 86.9±4.6%; pD2 8.7±0.24) of the endothelium-intact rat pulmonary artery. Combined presence of apamin and TRAM-34 significantly attenuated the relaxation (Emax 61.1±6.0%) to GSK. l-NAME (100μM) significantly attenuated (8.2±2.9%) the relaxation response to GSK that was resistant to apamin plus TRAM-34. However, presence of ICI192605 or furegrelate alongwith l-NAME revealed the GSK-mediated EDHF-response (Emax of 28.5±5.2%; Emax 24.5±4.3%) in this vessel, respectively. Further, these two TxA2 modulators (ICI/furegrelate) alongwith l-NAME had no effect on SNP-induced endothelium-independent relaxation in comparison to l-NAME alone. This EDHF-mediated relaxation was sensitive to inhibition by K(+) channel blockers apamin and TRAM-34 or 60mMK(+) depolarizing solution. Further, combined presence of apamin and TRAM-34 in U46619 pre-contracted pulmonary arterial rings significantly reduced the maximal relaxation (Emax 71.6±6.9%) elicited by GSK, but had no effect on the pD2 (8.1±0.03) of the TRPV4 channel agonist in comparison to controls (Emax, 92.4±4.3% and pD2, 8.3±0.06). The present study suggests that NO and EDHF are released concomitantly and NO synthase inhibition attenuates GSK-induced EDHF response through thromboxane pathway in the rat pulmonary artery. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  3. Bone sonometry: Reducing phase aberration to improve estimates of broadband ultrasonic attenuation

    PubMed Central

    Bauer, Adam Q.; Anderson, Christian C.; Holland, Mark R.; Miller, James G.

    2009-01-01

    Previous studies suggest that phase cancellation at the receiving transducer can result in the overestimation of the frequency dependent ultrasonic attenuation of bone, a quantity that has been shown to correlate with bone mineral density and ultimately with osteoporotic fracture risk. Evidence supporting this interpretation is provided by phase insensitive processing of the data, which appear to reduce the apparent overestimates of attenuation. The present study was designed to clarify the components underlying phase aberration artifacts in such through-transmission measurements by conducting systematic studies of the simplest possible test objects capable of introducing phase aberration. Experimental results are presented for a Lexan phantom over the frequency range 300–700 kHz and a Plexiglas phantom over the 3–7 MHz range. Both phantoms were flat and parallel plates featuring a step discontinuity milled into one of their initially flat sides. The through-transmitted signals were received by a 0.6 mm diameter membrane hydrophone that was raster scanned over a grid coaxial with the transmitting transducer. Signals received by the pseudoarray were processed offline to emulate phase sensitive and phase insensitive receivers with different aperture diameters. The data processed phase sensitively were focused to demonstrate the results of planar, geometrical, and correlation-based aberration correction methods. Results are presented illustrating the relative roles of interference in the ultrasonic field and phase cancellation at the receiving transducer in producing phase aberration artifacts. It was found that artifacts due to phase cancellation or interference can only be minimized with phase insensitive summation techniques by choosing an appropriately large receiving aperture. Data also suggest the potentially confounding role of time-and frequency-domain artifacts on ultrasonic measurements and illustrate the advantages of two-dimensional receiving arrays in

  4. Attenuation of postmenopausal bone loss in patients with transient hypoparathyroidism after total thyroidectomy.

    PubMed

    Takamura, Yuuki; Miyauchi, Akira; Yabuta, Tomonori; Kihara, Minoru; Ito, Yasuhiro; Miya, Akihiro

    2013-12-01

    Increased bone mineral density (BMD) has been reported in patients with postsurgical permanent hypoparathyroidism. Hypoparathyroidism may attenuate the high-turnover bone loss in postmenopausal women. We reported previously that patients who had transient hypoparathyroidism postoperatively were at subclinical hypoparathyroid (hP) status even 5 years after surgery. We hypothesized that patients with transient hypoparathyroidism (ThP) may have altered BMD. A total of 140 women who underwent total thyroidectomy had BMD measurements of the lumbar spine, femoral neck, and radius 3 years after surgery. At surgery, 99 patients were ≥50 years and 41 were <50 years. They were divided into three groups according to their postoperative parathyroid function: There were 80 patients in the no hP (NhP) group, 54 in the ThP group, and 6 in the permanent hP (PhP) group. Among the 99 patients aged ≥50 years, 36 ThP patients had median Z scores of the BMD in all three areas (lumbar spine, femoral neck, radius) that were significantly higher (by 1.083, 0.533, and 1.047, respectively) than those in the 60 NhP patients aged ≥50 years. The BMDs in the three PhP patients ≥50 years were higher than those in the NhP and ThP patients, but the difference did not reach significance except for in the femoral neck. Multivariate logistic regression analyses showed that Z scores > 0 were significantly associated only with the presence of ThP postoperatively. In the patients <50 years, the BMD values were not significantly different among the three groups except at the radius in PhP patients, which was significantly lower than those of the other patients. We found that ThP was associated with increased BMD in postmenopausal women. This may be due to attenuation of the high-turnover bone loss in postmenopausal women.

  5. Glucagon-like peptide-1 receptor agonist Liraglutide has anabolic bone effects in ovariectomized rats without diabetes.

    PubMed

    Lu, Nan; Sun, Hanxiao; Yu, JingJia; Wang, Xiaojing; Liu, Dongmei; Zhao, Lin; Sun, Lihao; Zhao, Hongyan; Tao, Bei; Liu, Jianmin

    2015-01-01

    Recently, a number of studies have demonstrated the potential beneficial role for novel anti-diabetic GLP-1 receptor agonists (GLP-1RAs) in the skeleton metabolism in diabetic rodents and patients. In this study, we evaluated the impacts of the synthetic GLP-1RA Liraglutide on bone mass and quality in osteoporotic rats induced by ovariectomy (OVX) but without diabetes, as well as its effect on the adipogenic and osteoblastogenic differentiation of bone marrow stromal cells (BMSCs). Three months after sham surgery or bilateral OVX, eighteen 5-month old female Wistar rats were randomly divided into three groups to receive the following treatments for 2 months: (1) Sham + normal saline; (2) OVX + normal saline; and (3) OVX + Liraglutide (0.6 mg/day). As revealed by micro-CT analysis, Liraglutide improved trabecular volume, thickness and number, increased BMD, and reduced trabecular spacing in the femurs in OVX rats; similar results were observed in the lumbar vertebrae of OVX rats treated with Liraglutide. Following in vitro treatment of rat and human BMSCs with 10 nM Liraglutide, there was a significant increase in the mRNA expression of osteoblast-specific transcriptional factor Runx2 and the osteoblast markers alkaline phosphatase (ALP) and collagen α1 (Col-1), but a significant decrease in peroxisome proliferator-activated receptor γ (PPARγ). In conclusion, our results indicate that the anti-diabetic drug Liraglutide can exert a bone protective effect even in non-diabetic osteoporotic OVX rats. This protective effect is likely attributable to the impact of Liraglutide on the lineage fate determination of BMSCs.

  6. Treatment with recombinant lubricin attenuates osteoarthritis by positive feedback loop between articular cartilage and subchondral bone in ovariectomized rats.

    PubMed

    Cui, Zhuang; Xu, Changpeng; Li, Xue; Song, Jinqi; Yu, Bin

    2015-05-01

    Osteoarthritis (OA) is a most commonly multifactorial degenerative joint disease along with the aging population, particularly in postmenopausal women. During the onset of OA, articular cartilage and subchondral bone act in concert as a functional unit. This present study is to investigate the effects of early or late treatment with recombinant lubricin on the onset of osteoarthritis (OA) in ovariectomized (OVX) rats. We found that both early and late recombinant lubricin treatments attenuated the onset of OA by positive feedback loop between articular cartilage and subchondral bone, although late treatment contributed to a lesser effect compared with early treatment. Specifically, treatment with recombinant lubricin protected articular cartilage from degeneration, demonstrated by lower proteoglycan loss, lower OARSI scores, less calcification cartilage zone and reduced immunostaining for collagen X (Col X) and matrix metalloproteinase (MMP-13) but increased the expression of lubricin, in comparison with vehicle-treated OVX rat group. Further, chondroprotective effects of lubricin normalized bone remodeling in subchondral bone underneath. It's suggested that treatment with recombinant lubricin inhibited the elevation of TRAP and Osterix positive cells in OVX rats and led to the normalization of subchondral bone microarchitectures with the suppression of subsidence of bone volume ratio (BV/TV) and trabecular thickness (Tb.Th) and the increase of trabecular separation (Tb.Sp) in vehicle-treated OVX rats. What's more, the normalization of subchondral bone in turn attenuated the articular cartilage erosion by inhibiting vascular invasion from subchondral bone to calcified cartilage zone, exemplified by inhibiting the elevation of CD31 positive cells in calcified cartilage and angiography in subchondral bone. Together, these results shed light that both early and late recombinant lubricin treatments attenuate the onset of OA by balancing the interplay between articular

  7. Trans-10, cis-12 conjugated linoleic acid and the PPAR-γ agonist rosiglitazone attenuate lipopolysaccharide-induced TNF-α production by bovine immune cells.

    PubMed

    Perdomo, M C; Santos, J E; Badinga, L

    2011-10-01

    Lipopolysaccharide (LPS) modulates innate immunity through alteration of cytokine production by immune cells. The objective of this study was to examine the effect of exogenous conjugated linoleic acid (CLA) and PPAR-γ agonist, rosiglitazone, on LPS-induced tumor necrosis factor α (TNF-α) production by cultured whole blood from prepubertal Holstein heifers (mean age, 5.5 mo). Compared with unstimulated cells, addition of LPS (10 μg/mL) to the culture medium increased (P<0.03) peripheral blood mononuclear cell proliferation≤2.5-fold. Coincubation with interferon γ (5 ng/mL) further stimulated (P<0.01) the lymphoproliferative response to LPS. Lipopolysaccharide increased (P<0.01) TNF-α concentration in cultured whole blood in a dose- and time-dependent manner. The greatest TNF-α stimulation occurred after 12 h of exposure to 1 μg/mL LPS. Coincubation with trans-10, cis-12 CLA isomer (100 μM) or rosiglitazone (10 μM), a PPAR-γ agonist, decreased (P<0.01) LPS-induced TNF-α production by 13% and 29%, respectively. Linoleic acid and cis-9, trans-11 CLA isomer had no detectable effects on LPS-induced TNF-α production in cultured bovine blood. The PPAR-γ agonist-induced TNF-α attenuation was reversed when blood was treated with both rosiglitazone and GW9662, a selective PPAR-γ antagonist. Addition of rosiglitazone to the culture medium tended to reduce nuclear factor-κ Bp65 concentration in nuclear and cytosolic extracts isolated from cultured peripheral blood mononuclear cells. Results show that LPS is a potent inducer of TNF-α production in bovine blood cells and that trans-10, cis-12 CLA and PPAR-γ agonists may attenuate the pro-inflammatory response induced by LPS in growing dairy heifers. Additional studies are needed to fully characterize the involvement of nuclear factor-κ B in LPS signaling in bovine blood cells.

  8. The peroxisome proliferator-activated receptor-α agonist, BAY PP1, attenuates renal fibrosis in rats.

    PubMed

    Boor, Peter; Celec, Peter; Martin, Ina V; Villa, Luigi; Hodosy, Július; Klenovicsová, Kristína; Esposito, Ciro; Schäfer, Stefan; Albrecht-Küpper, Barbara; Ostendorf, Tammo; Heidland, August; Šebeková, Katarína

    2011-12-01

    Recent studies have shown renoprotective effects of the peroxisome proliferator-activated receptor-α (PPAR-α), but its role in kidney fibrosis is unknown. In order to gain insight into this, we examined the effect of a novel PPAR-α agonist, BAY PP1, in two rat models of renal fibrosis: unilateral ureteral obstruction and the 5/6 nephrectomy. In healthy animals, PPAR-α was expressed in tubular but not in interstitial cells. Upon induction of fibrosis, PPAR-α was significantly downregulated, and treatment with BAY PP1 significantly restored its expression. During ureteral obstruction, treatment with BAY PP1 significantly reduced tubulointerstitial fibrosis, proliferation of interstitial fibroblasts, and TGF-β(1) expression. Treatment with a less potent PPAR-α agonist, fenofibrate, had no effects. Treatment with BAY PP1, initiated in established disease in the 5/6 nephrectomy, halted the decline of renal function and significantly ameliorated renal fibrosis. In vitro, BAY PP1 had no direct effect on renal fibroblasts but reduced collagen, fibronectin, and TGF-β(1) expression in tubular cells. Conditioned media of BAY PP1-treated tubular cells reduced fibroblast proliferation. Thus, renal fibrosis is characterized by a reduction of PPAR-α expression, and treatment with BAY PP1 restores PPAR-α expression and ameliorates renal fibrosis by modulating the cross-talk between tubular cells and fibroblasts. Hence, potent PPAR-α agonists might be useful in the treatment of renal fibrosis.

  9. Chronic ethanol-induced impairment of Wnt/β-catenin signaling is attenuated by PPAR-δ agonist

    PubMed Central

    Xu, Chelsea Q.; de la Monte, Suzanne M.; Tong, Ming; Huang, Chiung-Kuei; Kim, Miran

    2015-01-01

    Background The Wnt/β-catenin pathway regulates liver growth, repair, and regeneration. Chronic ethanol exposure blunts normal liver regenerative responses, in part by inhibiting insulin/IGF signaling, and correspondingly, previous studies showed that ethanol-impaired liver regeneration could be restored by insulin sensitizer (PPAR-δ agonist) treatment. Since Wnt/β-catenin functions overlap and crosstalk with insulin/IGF pathways, we investigated the effects of ethanol exposure and PPAR-δ agonist treatment on Wnt pathway gene expression in relation to liver regeneration. Methods Adult male Long Evans rats were fed with isocaloric liquid diets containing 0% or 37% ethanol for 8 weeks, and also treated with vehicle or a PPAR-δ agonist during the last 3 weeks of the feeding regimen. The rats were then subjected to 70% partial hepatectomy (PH) and livers harvested at various post-PH time points were used to quantify expression of 19 Wnt pathway genes using Quantigene 2.0 Multiplex Assay. Results Ethanol broadly inhibited expression of Wnt/β-catenin signaling-related genes, including down-regulation of Wnt1, Fzd3, Lef1, and Bcl9 throughout the post-PH time course (0-72 h), and suppression of Wnt7a, Ccnd1, Fgf4, Wif1, Sfrp2, and Sfrp5 at 18, 24 hours post-PH time points. PPAR-δ agonist treatments rescued the ethanol-induced suppression of Wnt1, Wnt7a, Fzd3, Lef1, Bcl9, Ccnd1, and Sfrp2 gene expression in liver, corresponding with the improvements in DNA synthesis and restoration of hepatic architecture. Conclusions Chronic high-dose ethanol exposures inhibit Wnt signaling, which likely contributes to the impairments in liver regeneration. Therapeutic effects of PPAR-δ agonists extend beyond restoration of insulin/IGF signaling mechanisms and are mediated in part by enhancement of Wnt pathway signaling. Future studies will determine the degree to which targeted restoration of Wnt signaling is sufficient to improve liver regeneration and remodeling in the context of

  10. PPAR Agonists Promote the Differentiation of Porcine Bone Marrow Mesenchymal Stem Cells into the Adipogenic and Myogenic Lineages.

    PubMed

    Pérez-Serrano, Rosa M; González-Dávalos, M Laura; Lozano-Flores, Carlos; Shimada, Armando; Antaramian, Anaid; Varela-Echavarría, Alfredo; Mora, Ofelia

    2017-01-01

    The aim of this work was to evaluate the effect of PPAR agonists on the differentiation and metabolic features of porcine mesenchymal stem cells induced to the adipogenic or myogenic lineages. Bone marrow MSCs from neonate pigs were isolated and identified by cell proliferation, cell surface markers or the gene expression of stem cells (CD44, CD90, CD105 or Oct4 and Nanog, respectively). Cells were differentiated into adipose or muscle cells and treated with the PPAR agonists; adipogenic and myogenic differentiation was promoted by adding these compounds. The expression of PPARγ (an adipose marker) and MyoD1 and MyHC (muscle markers), metabolic changes and expression levels of metabolic enzymes involved in glycolysis, lipogenesis, lipolysis and the pentose phosphate pathway were tested by qPCR. MSCs from neonate pigs exhibited high proliferation and were positive for CD44, CD90 and CD105 markers and Oct4 and Nanog expression. The treatment that promoted the highest expression of PPARγ was 50 µM of conjugated linoleic acid (CLA) c9 t11 (6.44 ± 0.69-fold, p ≤ 0.0001) in the adipose differentiation, and upregulation of HX2, ACCAα, ATGL, LPL and G6DP (p ≤ 0.0001) and downregulation of PFK and ACCAβ (p ≤ 0.0001) were found. For muscle differentiation, the best treatment was 50 µM of CLA c10 t12 (59.72 ± 4.72-fold, p ≤ 0.0001), and metabolic changes were upregulation of PFK, ACCAβ, G6DP, CPT1 and PPARβ/δ (p ≤ 0.0001), but no effect was observed with HX2 and ACCAα (p ≥ 0.05). Our results suggest that differentiated cells exhibit a typical cell lineage metabolism and higher efficiencies both in anabolism and catabolism. © 2016 S. Karger AG, Basel.

  11. A new cannabinoid CB2 receptor agonist HU-910 attenuates oxidative stress, inflammation and cell death associated with hepatic ischaemia/reperfusion injury

    PubMed Central

    Horváth, Bėla; Magid, Lital; Mukhopadhyay, Partha; Bátkai, Sándor; Rajesh, Mohanraj; Park, Ogyi; Tanchian, Galin; Gao, Rachel Y; Goodfellow, Catherine E; Glass, Michelle; Mechoulam, Raphael; Pacher, Pál

    2012-01-01

    BACKGROUND AND PURPOSE Cannabinoid CB2 receptor activation has been reported to attenuate myocardial, cerebral and hepatic ischaemia-reperfusion (I/R) injury. EXPERIMENTAL APPROACH We have investigated the effects of a novel CB2 receptor agonist ((1S,4R)-2-(2,6-dimethoxy-4-(2-methyloctan-2-yl)phenyl)-7,7-dimethylbicyclo[2.2.1]hept-2-en-1-yl)methanol (HU-910) on liver injury induced by 1 h of ischaemia followed by 2, 6 or 24 h of reperfusion, using a well-established mouse model of segmental hepatic I/R. KEY RESULTS Displacement of [3H]CP55940 by HU-910 from specific binding sites in CHO cell membranes transfected with human CB2 or CB1 receptors (hCB1/2) yielded Ki values of 6 nM and 1.4 µM respectively. HU-910 inhibited forskolin-stimulated cyclic AMP production by hCB2 CHO cells (EC50= 162 nM) and yielded EC50 of 26.4 nM in [35S]GTPγS binding assays using hCB2 expressing CHO membranes. HU-910 given before ischaemia significantly attenuated levels of I/R-induced hepatic pro-inflammatory chemokines (CCL3 and CXCL2), TNF-α, inter-cellular adhesion molecule-1, neutrophil infiltration, oxidative stress and cell death. Some of the beneficial effect of HU-910 also persisted when given at the beginning of the reperfusion or 1 h after the ischaemic episode. Furthermore, HU-910 attenuated the bacterial endotoxin-triggered TNF-α production in isolated Kupffer cells and expression of adhesion molecules in primary human liver sinusoidal endothelial cells stimulated with TNF-α. Pretreatment with a CB2 receptor antagonist attenuated the protective effects of HU-910, while pretreatment with a CB1 antagonist tended to enhance them. CONCLUSION AND IMPLICATIONS HU-910 is a potent CB2 receptor agonist which may exert protective effects in various diseases associated with inflammation and tissue injury. LINKED ARTICLES This article is part of a themed section on Cannabinoids in Biology and Medicine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph

  12. CT-measured bone attenuation in patients with chronic obstructive pulmonary disease: relation to clinical features and outcomes.

    PubMed

    Romme, Elisabeth A P M; Murchison, John T; Edwards, Lisa D; van Beek, Edwin; Murchison, David M; Rutten, Erica P A; Smeenk, Frank W J M; Williams, Michelle C; Wouters, Emiel F M; MacNee, William

    2013-06-01

    Osteoporosis is highly prevalent in chronic obstructive pulmonary disease (COPD) patients and has been related to several clinical features. However, most studies have been in relatively small COPD cohorts. Therefore, the objectives of this study were to compare bone attenuation measured on low-dose chest computed tomography (CT) between COPD subjects and smoker and nonsmoker controls, and to relate bone attenuation to clinical parameters, inflammatory biomarkers, and outcomes in a large, well-characterized COPD cohort. We studied 1634 COPD subjects, 259 smoker controls, and 186 nonsmoker controls who participated in a large longitudinal study (ECLIPSE). We measured bone attenuation, extent of emphysema, and coronary artery calcification (Agatston score) on baseline CT scans, and clinical parameters, inflammatory biomarkers, and outcomes. Bone attenuation was lower in COPD subjects compared with smoker and nonsmoker controls (164.9 ± 49.5 Hounsfield units [HU] versus 183.8 ± 46.1 HU versus 212.1 ± 54.4 HU, p < 0.001). Bone attenuation was not significantly different between COPD subjects and smoker controls after adjustment for age, sex, and pack-years of smoking. In the COPD subjects, bone attenuation correlated positively with forced expiratory volume in 1 second (FEV₁, r = 0.062, p = 0.014), FEV₁/forced vital capacity (FVC) ratio (r = 0.102, p < 0.001), body mass index (r = 0.243, p < 0.001), fat-free mass index (FFMI, r = 0.265, p < 0.001), and C-reactive protein (r = 0.104, p < 0.001), and correlated negatively with extent of emphysema (r = -0.090, p < 0.001), Agatston score (r = -0.177, p < 0.001), and interleukin-8 (r = -0.054, p = 0.035). In a multiple regression model, older age, lower FFMI and higher Agatston score were associated with lower bone attenuation. Lower bone attenuation was associated with higher exacerbation (r = -0.057, p = 0.022) and

  13. Z-505 hydrochloride, an orally active ghrelin agonist, attenuates the progression of cancer cachexia via anabolic hormones in Colon 26 tumor-bearing mice.

    PubMed

    Yoshimura, Makoto; Shiomi, Yoshihiro; Ohira, Yuta; Takei, Mineo; Tanaka, Takao

    2017-09-15

    Cancer cachexia is a progressive wasting syndrome characterized by anorexia and weight loss, specifically muscle wasting and fat depletion. There is no therapeutic agent for treatment of this syndrome. We investigated the anti-cachexia effects of Z-505 hydrochloride (Z-505), a new oral growth hormone secretagogue receptor 1a (GHSR1a) agonist, using a mouse model of cancer cachexia. We performed a calcium flux assay in Chinese hamster ovary (CHO-K1) cells stably expressing human GHSR1a to quantify the agonistic activity of Z-505. In Colon 26 tumor-bearing mice, Z-505 (300mg/kg, p.o., twice daily) was administered for 7 days to assess its anti-cachexia effects. Body weight and food intake were monitored during the period, and the skeletal muscle and epididymal fat weights were measured. Serum levels of insulin, insulin-like growth factor 1 (IGF-1), interleukin-6 (IL-6), and corticosterone were measured to confirm the mechanism of the anti-cachexia action of Z-505. Z-505 showed strong agonistic activity similar to that of human ghrelin, with a half maximal effective concentration (EC50) value of 0.45nM. Z-505 treatment significantly increased food intake and inhibited the progression of weight loss. Z-505 also significantly attenuated muscle wasting and fat loss, and increased circulating levels of anabolic factors such as insulin and IGF-1, but not catabolic factors such as IL-6 and corticosterone. These findings suggest that Z-505 might be effective in the treatment of cachexia via the increased anabolic hormone levels stimulated by the activation of the ghrelin receptor, GHSR1a. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Administration of the nicotinic acetylcholine receptor agonists ABT-089 and ABT-107 attenuates the reinstatement of nicotine-seeking behavior in rats

    PubMed Central

    Lee, Alycia M.; Arreola, Adrian C.; Kimmey, Blake A.; Schmidt, Heath D.

    2014-01-01

    Current smoking cessation pharmacotherapies have modest efficacy, and most smokers relapse within the first few days after a quit attempt. Nicotine withdrawal-induced craving and cognitive impairments predict smoking relapse during abstinence and suggest that cognitive-enhancing drugs may prevent relapse. ABT-089 and ABT-107 are subtype-selective nAChR agonists that improve cognitive performance in laboratory animals. However, there are no studies examining the effects of ABT-089 and ABT-107 on nicotine self-administration and the reinstatement of nicotine-seeking behavior, an animal model of relapse in human smokers. The goal of the present study was to determine the effects of the α4β2*/α6β2* nAChR agonist ABT-089 and the α7 nAChR agonist ABT-107 on nicotine taking and seeking in rats. The effects of acute ABT-089 and ABT-107 pretreatment on nicotine self-administration and reinstatement were tested in male Sprague Dawley rats. Parallel studies of ABT-089 and ABT-107 on sucrose self-administration and reinstatement were tested in separate groups of rats to determine if the effects of these drug treatments generalized to other reinforced behaviors. Nicotine and sucrose self-administration behaviors were not altered following acute administration of ABT-089 (0, 0.12, 1.2 and 12.0 mg/kg) or ABT-107 (0, 0.03 and 0.3 mg/kg). In contrast, both ABT-089 and ABT-107 pretreatment dose-dependently attenuated nicotine reinstatement. These effects were reinforcer-specific as no effects of ABT-089 or ABT-107 pretreatment on sucrose seeking were noted. Taken together, these findings suggest that ABT-089 and ABT-107 do not affect nicotine consumption, but may reduce the likelihood that a smoking lapse will lead to relapse. PMID:25128791

  15. A cannabinoid type 2 receptor agonist attenuates blood-brain barrier damage and neurodegeneration in a murine model of traumatic brain injury.

    PubMed

    Amenta, Peter S; Jallo, Jack I; Tuma, Ronald F; Elliott, Melanie B

    2012-12-01

    After traumatic brain injury (TBI), inflammation participates in both the secondary injury cascades and the repair of the CNS, both of which are influenced by the endocannabinoid system. This study determined the effects of repeated treatment with a cannabinoid type 2 receptor (CB(2) R) agonist on blood-brain barrier integrity, neuronal degeneration, and behavioral outcome in mice with TBI. We also looked for the presence of a prolonged treatment effect on the macrophage/microglial response to injury. C57BL/6 mice underwent controlled cortical impact (CCI) and received repeated treatments with a CB(2) R agonist, 0-1966, or vehicle. After euthanasia at 6 hr or 1, 2, 3, or 7 days postinjury, brains were removed for histochemical analysis. Blood-brain barrier permeability changes were evaluated by using sodium fluorescein (NaF). Perilesional degenerating neurons, injury volumes, and macrophage/microglia cells were quantified by stereological methods. Rota-rod and open-field testing were performed to evaluate motor function and natural exploratory behavior in mice. 0-1966 Treatment resulted in a significant reduction in NaF uptake and number of degenerating neurons compared with the vehicle-treated group. 0-1966-Treated mice demonstrated improvement on rota-rod and open-field testing compared with vehicle-treated mice. These changes in CCI mice treated with 0-1966 were associated with a prolonged reduction in macrophage/microglia cell counts. In conclusion, repeated treatments with a CB(2) R agonist, 0-1966, result in attenuated blood-brain barrier disruption and neuronal degeneration. In addition, repeated treatment with 0-1966 shows prolonged treatment effects on behavior and the macrophage/microglia cell response over several days.

  16. Spinal neuroimmmune activation is independent of T-cell infiltration and attenuated by A3 adenosine receptor agonists in a model of oxaliplatin-induced peripheral neuropathy

    PubMed Central

    Janes, Kali; Wahlman, Carrie; Little, Joshua W.; Doyle, Timothy; Tosh, Dillip K.; Jacobson, Kenneth A.; Salvemini, Daniela

    2014-01-01

    Many commonly used chemotherapeutics including oxaliplatin are associated with the development of a painful chemotherapy-induced peripheral neuropathy (CIPN). This dose-limiting complication can appear long after the completion of therapy causing a significant reduction in quality-of-life and impeding cancer treatment. We recently reported that activation of the Gi/Gq-coupled A3 adenosine receptor (A3AR) with selective A3AR agonists (i.e., IB-MECA) blocked the development of chemotherapy induced-neuropathic pain in models evoked by distinct agents including oxaliplatin without interfering with their anticancer activities. The mechanism(s) of action underlying these beneficial effects has yet to be explored. Our results demonstrate that the development of oxaliplatin-induced mechano-hypersensitivity (allodynia and hyperalgesia) in rats is associated with the hyperactivation of astrocytes, but not microglial cells, increased production of pro-inflammatory and neuroexcitatory cytokines (TNF, IL-1β), and reductions in the levels of anti-inflammatory/neuroprotective cytokines (IL-10, IL-4) in the dorsal horn of the spinal cord. These events did not require lymphocytic mobilization since oxaliplatin did not induce CD45+/CD3+ T-cell infiltration into the spinal cord. A3AR agonists blocked the development of neuropathic pain with beneficial effects strongly associated with the modulation of spinal neuroinflammatory processes: attenuation of astrocytic hyperactivation, inhibition of TNF and IL-1β production, and an increase in IL-10 and IL-4. These results suggest that inhibition of an astrocyte-associated neuroinflammatory response contributes to the protective actions of A3AR signaling and continues to support the pharmacological basis for selective A3AR agonists as adjuncts to chemotherapeutic agents for the management of chronic pain. PMID:25220279

  17. The PPARβ/δ agonist GW501516 attenuates peritonitis in peritoneal fibrosis via inhibition of TAK1-NFκB pathway in rats.

    PubMed

    Su, Xuesong; Zhou, Guangyu; Wang, Yanqiu; Yang, Xu; Li, Li; Yu, Rui; Li, Detian

    2014-06-01

    Peritoneal fibrosis is a common consequence of long-term peritoneal dialysis (PD), and peritonitis is a factor in its onset. Agonist-bound peroxisome proliferator-activated receptors (PPARs) function as key regulators of energy metabolism and inflammation. Here, we examined the effects of PPARβ/δ agonist GW501516 on peritonitis in a rat peritoneal fibrosis model. Peritoneal fibrosis secondary to inflammation was induced into uremic rats by daily injection of Dianeal 4.25% PD solutions along with six doses of lipopolysaccharide before commencement of GW501516 treatment. Normal non-uremic rats served as control, and all rats were fed with a control diet or a GW501516-containing diet. Compared to control group, exposure to PD fluids caused peritoneal fibrosis that was accompanied by increased mRNA levels of monocyte chemoattractant protein-1, tumor necrotic factor-α, and interleukin-6 in the uremic rats, and these effects were prevented by GW501516 treatment. Moreover, GW501516 was found to attenuate glucose-stimulated inflammation in cultured rat peritoneal mesothelial cells via inhibition of transforming growth factor-β-activated kinase 1 (TAK1), and nuclear factor kappa B (NFκB) signaling pathway (TAK1-NFκB pathway), a main inflammation regulatory pathway. In conclusion, inhibition of TAK1-NFκB pathway with GW501516 may represent a novel therapeutic approach to ameliorate peritonitis-induced peritoneal fibrosis for patients on PD.

  18. Peroxisome proliferator-activated receptor-γ agonist pioglitazone fails to attenuate renal fibrosis caused by unilateral ureteral obstruction in mice.

    PubMed

    Zhang, Ying; Wang, Jin; Zhou, Qiao-dan; Zhang, Cong-hui; Li, Qing; Huang, Shuai; Zhan, Juan; Wang, Kun; Liu, Yan-yan; Xu, Gang

    2016-02-01

    Renal tubulointerstitial fibrosis is the common ending of progressive renal disease. It is worth developing new ways to stop the progress of renal fibrosis. Peroxisome proliferator-activated receptor-γ (PPARγ) agonists have been studied to treat diabetic nephropathy, cisplatin-induced acute renal injury, ischemia reperfusion injury and adriamycin nephropathy. In this study, unilateral ureteral obstruction (UUO) was used to establish a different renal fibrosis model. PPAR? agonist pioglitazone was administrated by oral gavage and saline was used as control. At 7th and 14th day after the operation, mice were sacrificed for fibrosis test and T lymphocytes subsets test. Unexpectedly, through MASSON staining, immunohistochemistry for α-SMA, and Western blotting for a-SMA and PDGFR-β, we found that pioglitazone failed to attenuate renal fibrosis in UUO mice. However, flow cytometry showed that pioglitazone down-regulated Th1 cells, and up-regulated Th2 cells, Th17 cells and Treg cells. But the Th17/Treg ratio had no significant change by pioglitazone. Real-time PCR results showed that TGF-β and MCP-1 had no significant changes, at the same time, CD4(+) T cells associated cytokines were partially regulated by pioglitazone pretreatment. Taken together, pioglitazone failed to suppress renal fibrosis progression caused by UUO.

  19. CCR2 elimination in mice results in larger and stronger tibial bones but bone loss is not attenuated following ovariectomy or muscle denervation.

    PubMed

    Mader, Tara L; Novotny, Susan A; Lin, Angela S; Guldberg, Robert E; Lowe, Dawn A; Warren, Gordon L

    2014-11-01

    Bone loss due to age and disuse contributes to osteoporosis and increases fracture risk. It has been hypothesized that such bone loss can be attenuated by modulation of the C-C chemokine receptor 2 (CCR2) and/or its ligands. The objectives of this study were to examine the effects of genetic elimination of CCR2 on cortical and trabecular bones in the mouse tibia and how bone loss was impacted following disuse and estrogen loss. Female CCR2 knockout (CCR2(-/-)) and wildtype mice underwent ovariectomy (OVX) or denervation of musculature adjacent to the tibia (DEN) to induce bone loss. Cortical and trabecular structural properties as well as mechanical properties (i.e., strength) of tibial bones were measured. Compared to wildtype mice, CCR2(-/-) mice had tibiae that were up to 9% larger and stronger; these differences could be explained mainly by the 17% greater body mass (P < 0.001) of CCR2(-/-) mice. The majority of the tibia's structural and functional responses to OVX and DEN were similar regardless of the lack or presence of CCR2, indicating that CCR2 is not protective against bone loss per se. These findings indicate that while CCR2(-/-) mice do have larger and stronger bones than do wildtype mice, there is minimal evidence that CCR2 elimination provides protection against bone loss during disuse and estrogen loss.

  20. Norisoboldine, an Anti-Arthritis Alkaloid Isolated from Radix Linderae, Attenuates Osteoclast Differentiation and Inflammatory Bone Erosion in an Aryl Hydrocarbon Receptor-Dependent Manner.

    PubMed

    Wei, Zhi-feng; Lv, Qi; Xia, Ying; Yue, Meng-fan; Shi, Can; Xia, Yu-feng; Chou, Gui-xin; Wang, Zheng-tao; Dai, Yue

    2015-01-01

    Norisoboldine (NOR), the primary isoquinoline alkaloid constituent of the root of Lindera aggregata, has previously been demonstrated to attenuate osteoclast (OC) differentiation. Accumulative evidence has shown that aryl hydrocarbon receptor (AhR) plays an important role in regulating the differentiation of various cells, and multiple isoquinoline alkaloids can modulate AhR. In the present study, we explored the role of NOR in the AhR signaling pathway. These data showed that the combination of AhR antagonist resveratrol (Res) or α-naphthoflavone (α-NF) nearly reversed the inhibition of OC differentiation through NOR. NOR could stably bind to AhR, up-regulate the nuclear translocation of AhR, and enhance the accumulation of the AhR-ARNT complex, AhR-mediated reporter gene activity and CYP1A1 expression in RAW 264.7 cells, suggesting that NOR might be an agonist of AhR. Moreover, NOR inhibited the nuclear translocation of NF-κB-p65, resulting in the evident accumulation of the AhR-NF-κB-p65 complex, which could be markedly inhibited through either Res or α-NF. Although NOR only slightly affected the expression of HIF-1α, NOR markedly reduced VEGF mRNA expression and ARNT-HIF-1α complex accumulation. In vivo studies indicated that NOR decreased the number of OCs and ameliorated the bone erosion in the joints of rats with collagen-induced arthritis, accompanied by the up-regulation of CYP1A1 and the down-regulation of VEGF mRNA expression in the synovium of rats. A combination of α-NF nearly completely reversed the effects of NOR. In conclusion, NOR attenuated OC differentiation and bone erosion through the activation of AhR and the subsequent inhibition of both NF-κB and HIF pathways.

  1. The glucagon‐like peptide 1 receptor agonist liraglutide attenuates the reinforcing properties of alcohol in rodents

    PubMed Central

    Vallöf, Daniel; Maccioni, Paola; Colombo, Giancarlo; Mandrapa, Minja; Jörnulf, Julia Winsa; Egecioglu, Emil; Engel, Jörgen A.

    2015-01-01

    Abstract The incretin hormone, glucagon‐like peptide 1 (GLP‐1), regulates gastric emptying, glucose‐dependent stimulation of insulin secretion and glucagon release, and GLP‐1 analogs are therefore approved for treatment of type II diabetes. GLP‐1 receptors are expressed in reward‐related areas such as the ventral tegmental area and nucleus accumbens, and GLP‐1 was recently shown to regulate several alcohol‐mediated behaviors as well as amphetamine‐induced, cocaine‐induced and nicotine‐induced reward. The present series of experiments were undertaken to investigate the effect of the GLP‐1 receptor agonist, liraglutide, on several alcohol‐related behaviors in rats that model different aspects of alcohol use disorder in humans. Acute liraglutide treatment suppressed the well‐documented effects of alcohol on the mesolimbic dopamine system, namely alcohol‐induced accumbal dopamine release and conditioned place preference in mice. In addition, acute administration of liraglutide prevented the alcohol deprivation effect and reduced alcohol intake in outbred rats, while repeated treatment of liraglutide decreased alcohol intake in outbred rats as well as reduced operant self‐administration of alcohol in selectively bred Sardinian alcohol‐preferring rats. Collectively, these data suggest that GLP‐1 receptor agonists could be tested for treatment of alcohol dependence in humans. PMID:26303264

  2. Side effects of pharmacotherapy on bone with long-acting gonadorelin agonist triptorelin for paraphilia.

    PubMed

    Hoogeveen, John; Van der Veer, Eveline

    2008-03-01

    There have been limited research studies concerning the use of libido inhibitors for the treatment of patients with a paraphilia. Observational studies suggest that agents that lower testosterone are an effective treatment for paraphilia. We report a case of hormonal treatment of paraphilia that was associated with side effects. A 35-year-old man with a paraphilia was treated with long-acting gonadorelin. The desired result was reduced preoccupation with sexuality, but there were various side effects including a serious amount of bone loss. We believe that more attention should be given to the adverse effects of long-term treatment with triptorelin. In our view the drug regime needs to be revised.

  3. An Agonist of the Protective Factor SIRT1 Improves Functional Recovery and Promotes Neuronal Survival by Attenuating Inflammation after Spinal Cord Injury.

    PubMed

    Chen, Haihong; Ji, Hao; Zhang, Ming; Liu, Zude; Lao, Lifeng; Deng, Chao; Chen, Jianwei; Zhong, Guibin

    2017-03-15

    Targeting posttraumatic inflammation is crucial for improving locomotor function. SIRT1 has been shown to play a critical role in disease processes such as hepatic inflammation, rheumatoid arthritis, and acute lung inflammation by regulating inflammation. However, the role of SIRT1 in spinal cord injury (SCI) is unknown. We hypothesized that SIRT1 plays an important role in improving locomotor function after SCI by regulating neuroinflammation. In this study, we investigate the effect of SIRT1 in SCI using pharmacological intervention (SRT1720) and the Mx1-Cre/loxP recombination system to knock out target genes. First, we found that SIRT1 expression at the injured lesion site of wild-type (WT) mice (C57BL/6) decreased 4 h after SCI and lasted for 3 d. Moreover, administration of SRT1720, an agonist of SIRT1, to WT mice significantly improved functional recovery for up to 28 d after injury by reducing the levels of proinflammatory cytokines, the number of M1 macrophages, the number of macrophages/microglia, and the accumulation of perivascular macrophages. In contrast, administration of SRT1720 to SIRT1 knock-out (KO) mice did not improve locomotor recovery or attenuate inflammation. Furthermore, SIRT1 KO mice exhibited worse locomotor recovery, increased levels of inflammatory cytokines, and more M1 macrophages and perivascular macrophages than those of WT mice after SCI. Together, these findings indicate that SRT1720, an SIRT1 agonist, can improve functional recovery by attenuating inflammation after SCI. Therefore, SIRT1 is not only a protective factor but also an anti-inflammatory molecule that exerts beneficial effects on locomotor function after SCI.SIGNIFICANCE STATEMENT Posttraumatic inflammation plays a central role in regulating the pathogenesis of spinal cord injury (SCI). Here, new data show that administration of SRT1720, an SIRT1 agonist, to wild-type (WT) mice significantly improved outcomes after SCI, most likely by reducing the levels of

  4. Melatonin, but not melatonin receptor agonists Neu-P11 and Neu-P67, attenuates TNBS-induced colitis in mice.

    PubMed

    Zielińska, Marta; Jarmuż, Agata; Sałaga, Maciej; Kordek, Radzisław; Laudon, Moshe; Storr, Martin; Fichna, Jakub

    2016-05-01

    Melatonin is known as a strong antioxidant and possesses anti-inflammatory properties. Recently, melatonin was shown to improve colitis in animal models of inflammatory bowel diseases. The aim of the present study was to characterize the role of melatonin receptors (MT) in the anti-inflammatory effect of melatonin and to assess the anti-inflammatory potential of two novel MT receptor agonists, Neu-P11 and Neu-P67, in the mouse model of trinitrobenzenesulfonic acid (TNBS)-induced colitis. Colitis was induced on day 1 by intracolonic (i.c.) administration of TNBS in 30 % ethanol in saline. Melatonin (4 mg/kg, per os (p.o.)), Neu-P11 (20 mg/kg, p.o.; 50 mg/kg, intraperitoneally (i.p.), 50 mg/kg, i.c.), and Neu-P67 (20 mg/kg, p.o.) were given twice daily for 3 days. Luzindole (5 mg/kg, i.p.) was injected 15 min prior to melatonin administration. On day 4, macroscopic and microscopic damage scores were assessed and myeloperoxidase (MPO) activity quantified using O-dianisidine-based assay. Melatonin significantly attenuated colitis in mice, as indicated by the macroscopic score (1.90 ± 0.34 vs. 3.82 ± 0.62 for melatonin- and TNBS-treated mice, respectively), ulcer score (0.87 ± 0.18 vs. 1.31 ± 0.19, respectively), and MPO activity (4.68 ± 0.70 vs.6.26 ± 0.94, respectively). Luzindole, a MT receptor antagonist, did not inhibit the anti-inflammatory effect of melatonin (macroscopic score 1.12 ± 0.22, ulcer score 0.50 ± 0.16); however, luzindole increased MPO activity (7.57 ± 1.05). MT receptor agonists Neu-P11 and Neu-P67 did not improve inflammation induced by TNBS. Melatonin, but not MT receptor agonists, exerts potent anti-inflammatory action in acute TNBS-induced colitis. Our data suggests that melatonin attenuates colitis by additional, MT receptor-independent pathways.

  5. Monocyte chemotactic protein-1 deficiency attenuates and high-fat diet exacerbates bone loss in mice with Lewis lung carcinoma.

    PubMed

    Yan, Lin; Nielsen, Forrest H; Sundaram, Sneha; Cao, Jay

    2017-04-04

    Bone loss occurs in obesity and cancer-associated complications including wasting. This study determined whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects in male C57BL/6 mice with Lewis lung carcinoma (LLC) metastases in lungs. Compared to non-tumor-bearing mice, LLC reduced bone volume fraction, connectivity density, trabecular number, trabecular thickness and bone mineral density and increased trabecular separation in femurs. Similar changes occurred in vertebrae. The high-fat diet compared to the AIN93G diet exacerbated LLC-induced detrimental structural changes; the exacerbation was greater in femurs than in vertebrae. Mice deficient in MCP-1 compared to wild-type mice exhibited increases in bone volume fraction, connectivity density, trabecular number and decreases in trabecular separation in both femurs and vertebrae, and increases in trabecular thickness and bone mineral density and a decrease in structure model index in vertebrae. Lewis lung carcinoma significantly decreased osteocalcin but increased tartrate-resistant acid phosphatase 5b (TRAP 5b) in plasma. In LLC-bearing mice, the high-fat diet increased and MCP-1 deficiency decreased plasma TRAP 5b; neither the high-fat diet nor MCP-1 deficiency resulted in significant changes in plasma concentration of osteocalcin. In conclusion, pulmonary metastasis of LLC is accompanied by detrimental bone structural changes; MCP-1 deficiency attenuates and high-fat diet exacerbates the metastasis-associated bone wasting.

  6. Bone marrow-derived mesenchymal stem cell attenuates skin fibrosis development in mice.

    PubMed

    Wu, Yan; Huang, Sha; Enhe, Jirigala; Ma, Kui; Yang, Siming; Sun, Tongzhu; Fu, Xiaobing

    2014-12-01

    Recent studies showed that mesenchymal stem cell (MSC) transplantation significantly alleviated tissue fibrosis; however, little is known about the efficacy on attenuating cutaneous scar formation. In this study, we established a dermal fibrosis model induced by bleomycin and evaluated the benefit of bone marrow-derived mesenchymal stem cells (BM-MSCs) on skin fibrosis development. Tracing assay of green fluorescent protein (GFP(+) )BM-MSCs showed that the cells disappeared gradually within 24 hours upon administration, which hinted the action of BM-MSCs in vivo was exerted in the initial phase of repair in this model. Therefore, we repeatedly transplanted syngeneic BM-MSCs in the process of skin fibrosis formation. After 3 weeks, it was found that BM-MSC-treated lesional skin demonstrated a unanimous basket-weave organisation of collagen arrangement similar to normal skin, with few inflammatory cells. In addition, lesional skin with BM-MSC treatment exhibited a significant down-regulation of transforming growth factor-β1 (TGF-β1), type I collagen and heat-shock protein 47 (HSP47), with higher expression of matrix metalloproteinases (MMPs)-2, -9 and -13. Further experiments showed that α-smooth muscle actin (α-SMA) positive cells, the most reliable marker of myofibroblasts, apparently decreased after BM-MSC transplantation, which revealed that BM-MSCs could attenuate myofibroblast proliferation and differentiation as well as matrix production. Taken together, these findings suggested that BM-MSCs can inhibit the formation process of bleomycin-induced skin fibrosis, alleviate inflammation and favour the remodelling of extracellular matrix. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  7. Intrathecal injection of bone marrow stromal cells attenuates neurologic injury after spinal cord ischemia.

    PubMed

    Shi, Enyi; Kazui, Teruhisa; Jiang, Xiaojing; Washiyama, Naoki; Yamashita, Katsushi; Terada, Hitoshi; Bashar, Abul Hasan Muhammad

    2006-06-01

    It has been shown that transplantation of bone marrow stromal cells (MSCs) into the ischemic brain improves functional outcome. We sought to investigate whether intrathecal injection of MSCs can attenuate neurologic injury of spinal cord ischemia. Rabbit MSCs were expanded in vitro and were pre-labeled with bromodeoxyuridine. Spinal cord ischemia was induced in rabbits by infrarenal aortic occlusion. Group A and control A were subjected to a 20-minute ischemia and the ischemic duration was extended to 30 minutes in group B and control B. Two days before spinal cord ischemia, 1 x 10(8) MSCs were intrathecally injected into groups A and B, whereas vehicle alone was injected into the control groups. Hind-limb motor function was assessed during a 14-day recovery period with Tarlov criteria, and then histologic examination was performed. Marrow stromal cells survived and engrafted into the spinal cord 2 days after transplantation, and more MSCs were found in the lumbar spinal cord (ischemic segment) than in the thoracic spinal cord (nonischemic segment) at 14 days. Compared with their respective control groups, Tarlov scores were significantly higher in both groups A and B (p < 0.05, group A vs control A, at 2, 7, and 14 days; p < 0.05, group B vs control B, at 1, 2, 7, and 14 days, respectively). The number of intact motor neurons was much higher in the two experimental groups (p < 0.01 vs the corresponding control groups, respectively). Intrathecal injection of MSCs attenuates ischemic injury of spinal cord.

  8. Bone Marrow Mesenchymal Stem Cells Attenuate Mitochondria Damage Induced by Hypoxia in Mouse Trophoblasts

    PubMed Central

    Wang, Lingjuan; Xu, Xiaoyan; Kang, Lina

    2016-01-01

    Objective We aimed to observe the change of mitochondrial function and structure as well as the cell function induced by hypoxia in mouse trophoblasts, and moreover, to validate the restoration of these changes after co-culture with bone marrow mesenchymal stem cells (hereinafter referred to as “MSCs”). Further, we explored the mechanism of MSCs attenuating the functional damage of trophoblasts caused by hypoxia. Methods Cells were divided into two groups, trophoblasts and MSCs+trophoblasts respectively, and the two groups of cells were incubated with normoxia or hypoxia. Chemiluminescence was used to assay the β-HCG and progesterone in cell culture supernatants quantitatively. Western blotting and PCR were applied to detect the expression of Mfn2, MMP-2, MMP-9 and integrin β1 in the two groups. The mitochondrial membrane potential of each group of cells was detected with JC-1 dye and the ATP content was measured by the phosphomolybdic acid colorimetric method. We utilized transmission electron microscopy for observing the ultrastructure of mitochondria in trophoblasts. Finally, we assessed the cell apoptosis with flow cytometry (FCM) and analyzed the expression of the apoptosis related genes—Bcl-2, Bax, Caspase3 and Caspase9 by western blotting. Results The results showed that the Mfn2 expression was reduced after 4 h in hypoxia compared with that in normoxia, but increased in the co-culture group when compared with that in the separated-culture group (p<0.05). In addition, compared with the separated-culture group, theβ-HCG and progesterone levels in the co-culture group were significantly enhanced (p<0.05), and so were the expressions of MMP-2, MMP-9 and integrin β1 (p<0.05). Moreover, it exhibited significantly higher in ATP levels and intensified about the mitochondrial membrane potential in the co-culture group. TEM revealed disorders of the mitochondrial cristae and presented short rod-like structure and spheroids in hypoxia, however, in the co

  9. Different effects of agonistic vs. antagonistic gnrh-analogues (triptorelin vs. cetrorelix) on bone modeling and remodeling in peripubertal female rats.

    PubMed

    Roth, C L; Neu, C; Jarry, H; Schoenau, E

    2005-09-01

    Little is known about the effects of antagonistic GnRH analogues vs. agonists on bone strength, specifically in context of treating precocious puberty. Peripubertal female rats were treated from postnatal day 25 - 36 with either the GnRH agonist triptorelin (TRIP) or the antagonist cetrorelix (CET). Using peripherial quantitative computerized tomography (pQCT) we investigated effects on bone parameters. Onset of puberty was retarded by both analogues as measured by prevention of vaginal opening at 36 d of age and reduced uterine weights. In the tibia, cortical content, cortical area related to body weight, and periosteal circumference related to weight were significantly reduced in CET-treated rats - indicating reduced bone modeling and reduced bone strength (cortical circumference related to body weight: CET 0.066 +/- 0.001 vs. TRIP 0.068 +/- 0.001 vs. controls 0.071 +/- 0.001 mm/g, mean +/- SEM, p < 0.05 CET vs. controls; cortical area related to body weight: CET 3.87 +/- 0.46 vs. TRIP 6.80 +/- 0.63 vs. controls 8.07 +/- 1.13, x 10 (-3) mm (2)/g, p < 0.001 CET vs. controls; cortical content: CET 0.316 +/- 0.038 vs. TRIP 0.546 +/- 0.051 vs. controls 0.624 +/- 0.089 mg/mm, p < 0.01 CET vs. controls). In conclusion, although both CET and TRIP inhibit puberty in rats, cortical thinning was only seen in CET-treated rats. This indicates that GnRH antagonist treatment might cause reduced bone strength which is partly comparable to postmenopausal bone loss. When using new GnRH antagonists for treating precocious puberty in humans, parameters for bone strength and mineralization should be monitored.

  10. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    PubMed

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irene; Comtat, Claude

    2017-08-24

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach which estimates an AC map from an averaged CT template. As an alternative, we propose to use a Zero Echo Time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield Units (HU) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) for air and soft tissue and by using the linear relationship to generate a continuous LAC map for the bone. Additionally, for comparison purpose, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map where the bone is ignored and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map gen- erated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4 mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image. © 2017 Institute of Physics and Engineering in Medicine.

  11. Measurement of the normalized broadband ultrasound attenuation in trabecular bone by using a bidirectional transverse transmission technique

    NASA Astrophysics Data System (ADS)

    Lee, Kang Il

    2015-01-01

    A new method for measuring the normalized broadband ultrasound attenuation (nBUA) in trabecular bone by using a bidirectional transverse transmission technique was proposed and validated with measurements obtained by using the conventional transverse transmission technique. There was no significant difference between the nBUA measurements obtained for 14 bovine femoral trabecular bone samples by using the bidirectional and the conventional transverse transmission techniques. The nBUA measured by using the two transverse transmission techniques showed strong positive correlations of r = 0.87 to 0.88 with the apparent bone density, consistent with the behavior in human trabecular bone invitro. We expect that the new method can be usefully applied for improved accuracy and precision in clinical measurements.

  12. Risk of bone fractures associated with glucagon-like peptide-1 receptor agonists' treatment: a meta-analysis of randomized controlled trials.

    PubMed

    Su, Bin; Sheng, Hui; Zhang, Manna; Bu, Le; Yang, Peng; Li, Liang; Li, Fei; Sheng, Chunjun; Han, Yuqi; Qu, Shen; Wang, Jiying

    2015-02-01

    Traditional anti-diabetic drugs may have negative or positive effects on risk of bone fractures. Yet the relationship between the new class glucagon-like peptide-1 receptor agonists (GLP-1 RA) and risk of bone fractures has not been established. We performed a meta-analysis including randomized controlled trials (RCT) to study the risk of bone fractures associated with liraglutide or exenatide, compared to placebo or other active drugs. We searched MEDLINE, EMBASE, and clinical trial registration websites for published or unpublished RCTs comparing the effects of liraglutide or exenatide with comparators. Only studies with disclosed bone fracture data were included. Separate pooled analysis was performed for liraglutide or exenatide, respectively, by calculating Mantel-Haenszel odds ratio (MH-OR). 16 RCTs were identified including a total of 11,206 patients. Liraglutide treatment was associated with a significant reduced risk of incident bone fractures (MH-OR=0.38, 95% CI 0.17-0.87); however, exenatide treatment was associated with an elevated risk of incident bone fractures (MH-OR=2.09, 95% CI 1.03-4.21). Publication bias and heterogeneity between studies were not observed. Our study demonstrated a divergent risk of bone fractures associated with different GLP-1 RA treatments. The current findings need to be confirmed by future well-designed prospective or RCT studies.

  13. Fractal dimension of bone texture in radiographs correlates to ultrasound broadband attenuation T-score.

    PubMed

    Bianciardi, Giorgio; Bisogno, Stefania; Bertoldi, Ilaria; Laurini, Lorella; Coviello, Giuseppe; Frediani, Bruno

    2013-01-01

    We aimed to measure the fractal dimension on x-ray images and ultrasonographic parameters of the os calcis of bone from 4 districts in osteoporotic patients and in control subjects, in order to test the hypothesis that ultrasonographic parameters correlate to the fractal dimension obtained on x-ray images. Fractal analysis on radiological images from 4 bone districts (proximal femur, calcaneus, metacarpus and 3rd phalanx) was performed in a study comparing ultrasonographic evaluation of the os calcis in severe osteoporotic patients and in control cases. We studied 86 x-ray-views from patients with severe reduction of ultrasound Stiffness Index and in healthy women. Ultrasound measurements of left os calcis were performed using the Lunar Achilles-Plus instrument. Fractal analysis was performed using the box-counting method. In healthy subjects, fractal dimension, D, measure of structural complexity, resulted close to the topological dimension (no fractal structure), TD, in femur (1.99±0.03)and phalanx (1.96±0.03), D differed significantly from TD in calcaneus (D=1.90±0.02; p<0.001) and metacarpus (D=1.89±0.03, p<0.001). In osteoporotic subjects, in calcaneus and metacarpus, D was higher (1.94±0.03, 1.93±0.03, respectively) than in healthy subjects (1.90±0.02, 1.89±0.02, respectively, p<0.01). In all the subjects, fractal dimension and ultrasound broadband attenuation T-score correlated significantly in calcaneus and metacarpus (p<0.03 and p<0.02, respectively). Parameters based on a combination of ultrasonic examination and fractal analysis on radiographic images may add useful structural information regarding the patients' skeleton using non invasive procedures.

  14. Inhibition of SDF-1α/CXCR4 Signalling in Subchondral Bone Attenuates Post-Traumatic Osteoarthritis.

    PubMed

    Dong, Yonghui; Liu, Hui; Zhang, Xuejun; Xu, Fei; Qin, Liang; Cheng, Peng; Huang, Hui; Guo, Fengjing; Yang, Qing; Chen, Anmin

    2016-06-16

    Previous studies showed that SDF-1α is a catabolic factor that can infiltrate cartilage, decrease proteoglycan content, and increase MMP-13 activity. Inhibiting the SDF-1α/CXCR4 signalling pathway can attenuate the pathogenesis of osteoarthritis (OA). Recent studies have also shown that SDF-1α enhances chondrocyte proliferation and maturation. These results appear to be contradictory. In the current study, we used a destabilisation OA animal model to investigate the effects of SDF-1α/CXCR4 signalling in the tibial subchondral bone and the OA pathological process. Post-traumatic osteoarthritis (PTOA) mice models were prepared by transecting the anterior cruciate ligament (ACLT), or a sham surgery was performed, in a total of 30 mice. Mice were treated with phosphate buffer saline (PBS) or AMD3100 (an inhibitor of CXCR4) and sacrificed at 30 days post ACLT or sham surgery. Tibial subchondral bone status was quantified by micro-computed tomography (μCT). Knee-joint histology was analysed to examine the articular cartilage and joint degeneration. The levels of SDF-1α and collagen type I c-telopeptidefragments (CTX-I) were quantified by ELISA. Bone marrow mononuclear cells (BMMCs) were used to clarify the effects of SDF-1α on osteoclast formation and activity in vivo. μCT analysis revealed significant loss of trabecular bone from tibial subchondral bone post-ACLT, which was effectively prevented by AMD3100. AMD3100 could partially prevent bone loss and articular cartilage degeneration. Serum biomarkers revealed an increase in SDF-1α and bone resorption, which were also reduced by AMD3100. SDF-1α can promote osteoclast formation and the expression oftartrate resistant acid phosphatase (TRAP), cathepsin K (CK), and matrix metalloproteinase (MMP)-9 in osteoclasts by activating the MAPK pathway, including ERK and p38, but not JNK. In conclusion, inhibition of SDF-1α/CXCR4signalling was able to prevent trabecular bone loss and attenuated cartilage degeneration in

  15. PPARα agonist fenofibrate attenuates TNF-α-induced CD40 expression in 3T3-L1 adipocytes via the SIRT1-dependent signaling pathway.

    PubMed

    Wang, Weirong; Lin, Qinqin; Lin, Rong; Zhang, Jiye; Ren, Feng; Zhang, Jianfeng; Ji, Meixi; Li, Yanxiang

    2013-06-10

    The ligand-activated transcription factor peroxisome proliferator-activated receptor-α (PPARα) participates in the regulation of cellular inflammation. More recent studies indicated that sirtuin1 (SIRT1), a NAD(+)-dependent deacetylase, regulates the inflammatory response in adipocytes. However, whether the role of PPARα in inflammation is mediated by SIRT1 remains unclear. In this study, we aimed to determine the effect of PPARα agonist fenofibrate on the expressions of SIRT1 and pro-inflammatory cytokine CD40 and underlying mechanisms in 3T3-L1 adipocytes. We found that fenofibrate inhibited CD40 expression and up-regulated SIRT1 expression in tumor necrosis factor-α (TNF-α)-stimulated adipocytes, and these effects of fenofibrate were reversed by PPARα antagonist GW6471. Moreover, SIRT1 inhibitors sirtinol/nicotinamide (NAM) or knockdown of SIRT1 could attenuate the effect of fenofibrate on TNF-α-induced CD40 expression in adipocytes. Importantly, NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) augmented the effect of fenofibrate on CD40 expression in adipocytes. Further study found that fenofibrate decreased the expression of acetylated-NF-κB p65 (Ac-NF-κB p65) in TNF-α-stimulated adipocytes, and the effect of fenofibrate was abolished by SIRT1 inhibition. In addition, fenofibrate up-regulated SIRT1 expression through AMPK in TNF-α-stimulated adipocytes. Taken together, these findings indicate that PPARα agonist fenofibrate inhibits TNF-α-induced CD40 expression in 3T3-L1 adipocytes via the SIRT1-dependent signaling pathway. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Cannabinoids Receptor-2 (CB2) agonist ameliorates colitis in IL-10−/− mice by attenuating the activation of T cells and promoting their apoptosis

    PubMed Central

    Singh, Udai P.; Singh, Narendra P.; Singh, Balwan; Price, Robert L.; Nagarkatti, Mitzi; Nagarkatti, Prakash S.

    2014-01-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammation caused by hyperactivated effector immune cells that produce pro-inflammatory cytokines. Recent studies have shown that the cannabinoid system may play a critical role in mediating protection against intestinal inflammation. However, the effect of cannabinoid receptors induction after chronic colitis progression has not been investigated. Here, we investigate the effect of cannabinoid receptor-2 (CB2) agonist, JWH-133, after chronic colitis in IL-10−/− mice. JWH-133 effectively attenuated the overall clinical score, reversed colitis-associated pathogenesis and decrease in body weight in IL-10−/− mice. After JWH-133 treatment, the percentage of CD4+ T cells, neutrophils, mast cells, natural killer (NK1.1) cells, and activated T cells in the LP of colitis mice declined after JWH-133 treatment in the intestinal lamina propria (LP) and mesenteric lymph nodes (MLN). JWH-133 was also effective in ameliorating dextran sodium sulphate (DSS)-induced colitis. In this model, JWH-133 reduced the number and percentage of macrophages and IFN-γ expressing cells that were induced during colitis progression. Treatment with aminoalkylindole 6-iodopravadoline (AM630), a CB2 receptor antagonist, reversed the colitis protection provided by JWH-133 treatment. Also, activated T cells were found to undergo apoptosis following JWH-133 treatment both in-vivo and in-vitro. These findings suggest that JWH-133 mediates its effect through CB2 receptors, and ameliorates chronic colitis by inducing apoptosis in activated T cells, reducing the numbers of activated T cells, suppressing induction of mast cells, NK cells, and neutrophils at sites of inflammation in the LP. These results support the idea that the CB2 receptor agonists may serve as a therapeutic modality against IBD. PMID:22119709

  17. Retinoic acid receptor agonist Am80 inhibits CXCL2 production from microglial BV-2 cells via attenuation of NF-κB signaling.

    PubMed

    Takaoka, Yuichiro; Takahashi, Moeka; Kurauchi, Yuki; Hisatsune, Akinori; Seki, Takahiro; Shudo, Koichi; Katsuki, Hiroshi

    2016-09-01

    Accumulating lines of evidence suggest that retinoic acid receptor agonists such as Am80 exerts anti-inflammatory actions in the central nervous system, although detailed mechanisms of the action remain largely unknown. Our previous findings suggest that Am80 provides therapeutic effect on intracerebral hemorrhage in mice via suppression of expression of chemokine (C-X-C motif) ligand 2 (CXCL2). Here we investigated the mechanisms of inhibitory action of Am80 on expression of CXCL2 and other pro-inflammatory factors in microglial BV-2 cells. Pretreatment with Am80 markedly suppressed lipopolysaccharide (LPS)-induced expression of CXCL2 mRNA and release of CXCL2 protein. Am80 had no effect on LPS-induced activation of p38 mitogen-activated protein kinase and extracellular signal-regulated kinase. On the other hand, Am80 prevented LPS-induced nuclear translocation of p65 subunit of NF-κB complex. In addition, total expression levels of p65 and IκBα proteins, as well as of mRNAs encoding p65 and IκBα, were lowered by Am80. Dependence of CXCL2 expression on NF-κB was confirmed by the effect of an NF-κB inhibitor caffeic acid phenethyl ester that abolished LPS-induced CXCL2 expression. Caffeic acid phenethyl ester also abolished LPS-induced expression of inducible nitric oxide synthase, interleukin-1β and tumor necrosis factor α, which may be relevant to the inhibitory effect of Am80 on expression of these pro-inflammatory factors. We additionally found that Am80 attenuated LPS-induced up-regulation of CD14, a co-receptor for Toll-like receptor 4 (TLR4). These results suggest that inhibitory effect on TLR4 signaling mediated by NF-κB pathway underlies the anti-inflammatory action of retinoic acid receptor agonists in microglia.

  18. Propranolol, a β-adrenergic antagonist, attenuates the decrease in trabecular bone mass in high calorie diet fed growing mice

    PubMed Central

    Baek, Kyunghwa; Hwang, Hyo Rin; Park, Hyun-Jung; Kwon, Arang; Qadir, Abdul S.; Baek, Jeong-Hwa

    2014-01-01

    We investigated the effects of high calorie and low calorie diets on skeletal integrity, and whether β-adrenergic blockade (BB) attenuates bone loss induced by dietary calorie alteration. Male 6-week-old C57BL/6 mice were assigned to either an ad-lib fed control diet (CON), a high calorie diet (HIGH), or a low calorie diet (LOW) group. In each diet group, mice were treated with either vehicle (VEH) or propranolol, a β-adrenergic antagonist. Over 12-weeks, β-blockade mitigated body weight and fat mass increases induced by the high calorie diet. Femoral trabecular bone mineral density and the expression levels of osteogenic marker genes in bone marrow cells were reduced in HIGHVEH and LOWVEH mice, and BB significantly attenuated this decline only in HIGH mice. In summary, the magnitude of bone loss induced by low calorie diet was greater than that caused by high calorie diet in growing mice, and β-blockade mitigated high calorie diet-induced bone loss. [BMB Reports 2014; 47(9): 506-511] PMID:24393528

  19. Propranolol, a β-adrenergic antagonist, attenuates the decrease in trabecular bone mass in high calorie diet fed growing mice.

    PubMed

    Baek, Kyunghwa; Hwang, Hyo Rin; Park, Hyun-Jung; Kwon, Arang; Qadir, Abdul S; Baek, Jeong-Hwa

    2014-09-01

    We investigated the effects of high calorie and low calorie diets on skeletal integrity, and whether β-adrenergic blockade (BB) attenuates bone loss induced by dietary calorie alteration. Male 6-week-old C57BL/6 mice were assigned to either an ad-lib fed control diet (CON), a high calorie diet (HIGH), or a low calorie diet (LOW) group. In each diet group, mice were treated with either vehicle (VEH) or propranolol, a β-adrenergic antagonist. Over 12-weeks, β-blockade mitigated body weight and fat mass increases induced by the high calorie diet. Femoral trabecular bone mineral density and the expression levels of osteogenic marker genes in bone marrow cells were reduced in HIGHVEH and LOWVEH mice, and BB significantly attenuated this decline only in HIGH mice. In summary, the magnitude of bone loss induced by low calorie diet was greater than that caused by high calorie diet in growing mice, and β-blockade mitigated high calorie diet-induced bone loss.

  20. Intravenous Immunoglobulin (IVIG) Attenuates TNF-induced Pathologic Bone Resorption and Suppresses Osteoclastogenesis by Inducing A20 Expression

    PubMed Central

    Mun, Sehwan; Bae, Seyeon; Murata, Koichi; Ivashkiv, Lionel B.; Park-Min, Kyung-Hyun

    2016-01-01

    Investigations on the therapeutic effects of intravenous immunoglobulin (IVIG) have focused on the suppression of autoantibody- and immune complex-mediated inflammatory pathogenesis. Inflammatory diseases such as rheumatoid arthritis are often accompanied by excessive bone erosion but the effect of IVIG on osteoclasts, bone-resorbing cells, has not been studied. Here, we investigate whether IVIG directly regulates osteoclast differentiation and has therapeutic potential for suppressing osteoclast-mediated pathologic bone resorption. IVIG or cross-linking of Fcγ receptors with plate-bound IgG suppressed receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis and expression of osteoclast-related genes such as integrin β3 and cathepsin K in a dose-dependent manner. Mechanistically, IVIG or plate-bound IgG suppressed osteoclastogenesis by downregulating RANKL-induced expression of NFATC1, the master regulator of osteoclastogenesis. IVIG suppressed NFATC1 expression by attenuating RANKL-induced NF-κB signaling, explained in part by induction of the inflammatory signaling inhibitor A20. IVIG administration attenuated in vivo osteoclastogenesis and suppressed bone resorption in the tumor necrosis factor (TNF)-induced calvarial osteolysis model. Our findings show that, in addition to suppressing inflammation, IVIG directly inhibits osteoclastogenesis through a mechanism involving suppression of RANK signaling. Direct suppression of osteoclast differentiation may provide beneficial effects on preserving bone mass when IVIG is used to treat rheumatic disorders. PMID:26189496

  1. Cannabinoid receptor-2 (CB2) agonist ameliorates colitis in IL-10{sup −/−} mice by attenuating the activation of T cells and promoting their apoptosis

    SciTech Connect

    Singh, Udai P.; Singh, Narendra P.; Singh, Balwan; Price, Robert L.; Nagarkatti, Mitzi; Nagarkatti, Prakash S.

    2012-01-15

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammation caused by hyperactivated effector immune cells that produce pro-inflammatory cytokines. Recent studies have shown that the cannabinoid system may play a critical role in mediating protection against intestinal inflammation. However, the effect of cannabinoid receptor induction after chronic colitis progression has not been investigated. Here, we investigate the effect of cannabinoid receptor-2 (CB2) agonist, JWH-133, after chronic colitis in IL-10{sup −/−} mice. JWH-133 effectively attenuated the overall clinical score, and reversed colitis-associated pathogenesis and decrease in body weight in IL-10{sup −/−} mice. After JWH-133 treatment, the percentage of CD4{sup +} T cells, neutrophils, mast cells, natural killer (NK1.1) cells, and activated T cells declined in the intestinal lamina propria (LP) and mesenteric lymph nodes (MLN) of mice with chronic colitis. JWH-133 was also effective in ameliorating dextran sodium sulfate (DSS)-induced colitis. In this model, JWH-133 reduced the number and percentage of macrophages and IFN-γ expressing cells that were induced during colitis progression. Treatment with aminoalkylindole 6-iodo-pravadoline (AM630), a CB2 receptor antagonist, reversed the colitis protection provided by JWH-133 treatment. Also, activated T cells were found to undergo apoptosis following JWH-133 treatment both in-vivo and in-vitro. These findings suggest that JWH-133 mediates its effect through CB2 receptors, and ameliorates chronic colitis by inducing apoptosis in activated T cells, reducing the numbers of activated T cells, and suppressing induction of mast cells, NK cells, and neutrophils at sites of inflammation in the LP. These results support the idea that the CB2 receptor agonists may serve as a therapeutic modality against IBD. -- Highlights: ► JWH-133, a cannnabinoid receptor-2 agonist ameliorates experimental colitis. ► JWH-133 suppressed inflammation and

  2. Inhibition of bone morphogenetic protein signaling attenuates anemia associated with inflammation.

    PubMed

    Steinbicker, Andrea U; Sachidanandan, Chetana; Vonner, Ashley J; Yusuf, Rushdia Z; Deng, Donna Y; Lai, Carol S; Rauwerdink, Kristen M; Winn, Julia C; Saez, Borja; Cook, Colleen M; Szekely, Brian A; Roy, Cindy N; Seehra, Jasbir S; Cuny, Gregory D; Scadden, David T; Peterson, Randall T; Bloch, Kenneth D; Yu, Paul B

    2011-05-05

    Anemia of inflammation develops in settings of chronic inflammatory, infectious, or neoplastic disease. In this highly prevalent form of anemia, inflammatory cytokines, including IL-6, stimulate hepatic expression of hepcidin, which negatively regulates iron bioavailability by inactivating ferroportin. Hepcidin is transcriptionally regulated by IL-6 and bone morphogenetic protein (BMP) signaling. We hypothesized that inhibiting BMP signaling can reduce hepcidin expression and ameliorate hypoferremia and anemia associated with inflammation. In human hepatoma cells, IL-6-induced hepcidin expression, an effect that was inhibited by treatment with a BMP type I receptor inhibitor, LDN-193189, or BMP ligand antagonists noggin and ALK3-Fc. In zebrafish, the induction of hepcidin expression by transgenic expression of IL-6 was also reduced by LDN-193189. In mice, treatment with IL-6 or turpentine increased hepcidin expression and reduced serum iron, effects that were inhibited by LDN-193189 or ALK3-Fc. Chronic turpentine treatment led to microcytic anemia, which was prevented by concurrent administration of LDN-193189 or attenuated when LDN-193189 was administered after anemia was established. Our studies support the concept that BMP and IL-6 act together to regulate iron homeostasis and suggest that inhibition of BMP signaling may be an effective strategy for the treatment of anemia of inflammation.

  3. Raloxifene Administration in Women Treated with Long Term Gonadotropin-releasing Hormone Agonist for Severe Endometriosis: Effects on Bone Mineral Density

    PubMed Central

    Cho, Young Hwa; Um, Mi Jung; Kim, Suk Jin; Kim, Soo Ah

    2016-01-01

    Objectives To evaluate the efficacy of raloxifene in preventing bone loss associated with long term gonadotropin-releasing hormone agonist (GnRH-a) administration. Methods Twenty-two premenopausal women with severe endometriosis were treated with leuprolide acetate depot at a dosage of 3.75 mg/4 weeks, for 48 weeks. Bone mineral density (BMD) was evaluated at admission, and after 12 treatment cycles. Results At cycle 12 of GnRH-a plus raloxifene treatment, lumbar spine, trochanter femoral neck, and Ward's BMD differed from before the treatment. A year after treatment, the lumbar spine and trochanter decreased slightly, but were not significantly different. Conclusions Our study shows that the administration of GnRH-a plus raloxifene in pre-menopausal women with severe endometriosis, is an effective long-term treatment to prevent bone loss. PMID:28119898

  4. Cannabinoid receptor type 2 agonist attenuates apoptosis by activation of phosphorylated CREB-Bcl-2 pathway after subarachnoid hemorrhage in rats.

    PubMed

    Fujii, Mutsumi; Sherchan, Prativa; Soejima, Yoshiteru; Hasegawa, Yu; Flores, Jerry; Doycheva, Desislava; Zhang, John H

    2014-11-01

    Early brain injury (EBI) which comprises of vasogenic edema and apoptotic cell death is an important component of subarachnoid hemorrhage (SAH) pathophysiology. This study evaluated whether cannabinoid receptor type 2 (CB2R) agonist, JWH133, attenuates EBI after SAH and whether CB2R stimulation reduces pro-apoptotic caspase-3 via up-regulation of cAMP response element-binding protein (CREB)-Bcl-2 signaling pathway. Male Sprague-Dawley rats (n=123) were subjected to SAH by endovascular perforation. Rats received vehicle or JWH133 at 1h after SAH. Neurological deficits and brain water content were evaluated at 24h after SAH. Western blot was performed to quantify phosphorylated CREB (pCREB), Bcl-2, and cleaved caspase-3 levels. Neuronal cell death was evaluated with terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end-labeling staining. Additionally, CREB siRNA was administered to manipulate the proposed pathway. JWH133 (1.0mg/kg) improved neurological deficits and reduced brain water content in left hemisphere 24h after SAH. JWH133 significantly increased activated CREB (pCREB) and Bcl-2 levels and significantly decreased cleaved caspase-3 levels in left hemisphere 24h after SAH. CREB siRNA reversed the effects of treatment. TUNEL positive neurons in the cortex were reduced with JWH133 treatment. Thus, CB2R stimulation attenuated EBI after SAH possibly through activation of pCREB-Bcl-2 pathway. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    NASA Astrophysics Data System (ADS)

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

    2017-10-01

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units (HU ) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4~mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

  6. Targeting cells of the myeloid lineage attenuates pain and disease progression in a prostate model of bone cancer.

    PubMed

    Thompson, Michelle L; Jimenez-Andrade, Juan M; Chartier, Stephane; Tsai, James; Burton, Elizabeth A; Habets, Gaston; Lin, Paul S; West, Brian L; Mantyh, Patrick W

    2015-09-01

    Tumor cells frequently metastasize to bone where they can generate cancer-induced bone pain (CIBP) that can be difficult to fully control using available therapies. Here, we explored whether PLX3397, a high-affinity small molecular antagonist that binds to and inhibits phosphorylation of colony-stimulating factor-1 receptor, the tyrosine-protein kinase c-Kit, and the FMS-like tyrosine kinase 3, can reduce CIBP. These 3 targets all regulate the proliferation and function of a subset of the myeloid cells including macrophages, osteoclasts, and mast cells. Preliminary experiments show that PLX3397 attenuated inflammatory pain after formalin injection into the hind paw of the rat. As there is an inflammatory component in CIBP, involving macrophages and osteoclasts, the effect of PLX3397 was explored in a prostate model of CIBP where skeletal pain, cancer cell proliferation, tumor metastasis, and bone remodeling could be monitored in the same animal. Administration of PLX3397 was initiated on day 14 after prostate cancer cell injection when the tumor was well established, and tumor-induced bone remodeling was first evident. Over the next 6 weeks, sustained administration of PLX3397 attenuated CIBP behaviors by approximately 50% and was equally efficacious in reducing tumor cell growth, formation of new tumor colonies in bone, and pathological tumor-induced bone remodeling. Developing a better understanding of potential effects that analgesic therapies have on the tumor itself may allow the development of therapies that not only better control the pain but also positively impact disease progression and overall survival in patients with bone cancer.

  7. A comparison between the patella and the calcaneus using ultrasound velocity and attenuation as predictors of bone mineral density

    NASA Astrophysics Data System (ADS)

    Han, S. M.; Davis, J.

    1997-10-01

    The bone mineral density (BMD), ultrasound velocity (UV) and attenuation were examined in sixteen matched sets of human patellae and calcanei. For the sixteen calcanei, BMD was strongly correlated with all ultrasound parameters. Calcaneal UV appeared to be inferior to attenuation in the ability to predict BMD. For the sixteen patellae, the average UV was found to be greater in the superior/inferior direction than in the anterior/posterior and medial/lateral directions. It was found that patella BMD was significantly correlated with each of three directional ultrasound velocities. The relationship between BMD and ultrasound attenuation parameters was not significant in the patella. A comparative study of the two different bone sets demonstrated that the BMDs of the patella and calcaneus were significantly correlated with each other. Ultrasound velocity of calcaneus, measured in the medial/lateral direction, was not significantly associated with any of three directional ultrasound velocities in the patella. Similarly, ultrasound attenuation parameters of calcaneus were not significantly correlated with those of patella. The present study also demonstrated evidence that when predicting BMDs at their respective sites using ultrasound, the calcaneus appeared to be superior to the patella.

  8. An NMDA antagonist (LY 235959) attenuates abstinence-induced withdrawal of planarians following acute exposure to a cannabinoid agonist (WIN 55212-2).

    PubMed

    Rawls, Scott M; Gomez, Teresa; Raffa, Robert B

    2007-03-01

    The mechanisms that facilitate the development and expression of cannabinoid physical dependence in humans and other mammals are poorly understood. The present experiments used a planarian model to provide evidence that pharmacological antagonism of NMDA receptors significantly attenuates the development of cannabinoid physical dependence. Abstinence-induced withdrawal from the cannabinoid agonist WIN 55212-2 (10 microM) was manifested as a significant (P<0.05) decrease in the rate of planarian spontaneous locomotor velocity (pLMV) when WIN 55212-2 (10 microM)-exposed planarians were placed into drug-free water. No change in pLMV occurred when WIN 55212-2 (10 microM)-exposed planarians were placed into water containing WIN 55212-2 (10 microM). WIN 55212-2 (10 microM)-exposed planarians placed into water containing LY 235959 (1 or 10 microM) did not display withdrawal (no significant difference, P>0.05, in pLMV). In addition, withdrawal was not observed (no significant difference, P>0.05, in pLMV) in planarians that were co-exposed to a solution containing WIN 55212-2 (10 microM) and LY 235959 (10 microM). The present results reveal that NMDA receptor activation mediates the development of cannabinoid physical dependence and the expression of cannabinoid withdrawal in planarians.

  9. A nitric oxide synthase inhibitor (L-NAME) attenuates abstinence-induced withdrawal from both cocaine and a cannabinoid agonist (WIN 55212-2) in Planaria.

    PubMed

    Rawls, Scott M; Rodriguez, Tonatiu; Baron, David A; Raffa, Robert B

    2006-07-12

    We previously reported that planarians (Dugesia dorotocephala) that have been exposed to cocaine for 1 h undergo abstinence-induced withdrawal when placed into cocaine-free, but not cocaine-containing, water. We now report that planarians also display dose-related abstinence-induced withdrawal following exposure to the synthetic cannabinoid agonist WIN 55212-2, but not its inactive enantiomer (WIN 55212-3). The withdrawal from WIN 55212-2 was manifested as a significant (P < 0.05) decrease in the rate of planarian spontaneous locomotor activity over a 5-min observation period, using a recently designed metric (pLMV). We also report that withdrawal from cocaine (80 microM) or WIN 55212-2 (10 microM) was attenuated by the selective inhibitor of nitric oxide synthesis L-NAME (L-nitro-arginine methyl ester), which had no effect of its own on pLMV. These results suggest a common NO-dependent pathway of withdrawal from cocaine and WIN 55212-2 in Planaria.

  10. Chronic cocaine self-administration attenuates the anxiogenic-like and stress potentiating effects of the benzodiazepine inverse agonist, FG 7142.

    PubMed

    Waters, R Parrish; See, Ronald E

    2011-09-01

    Stress is a well-known risk factor in relapse to drug abuse. Several forms of stress in animals have been used with varied degrees of success to elicit reinstatement of drug-seeking after chronic drug self-administration. Here, we tested the ability of the benzodiazepine (BZ) inverse agonist, FG 7142, to elicit anxiety-like behavior and potentiate stress responses in rats as measured by standard behavioral and hormonal indices and for its ability to affect reinstatement of cocaine-seeking in rats with a prior history of cocaine self-administration. FG 7142 elicited anxiety-like behavior on the elevated plus maze (EPM) in cocaine-naïve rats, and cocaine-naïve rats injected with FG 7142 exhibited increased plasma corticosterone levels following EPM exposure. However, in animals with a history of cocaine self-administration, FG 7142 failed to affect elevated plus maze performance and did not affect plasma corticosterone response to the EPM. Furthermore, FG 7142 failed to reinstate cocaine-seeking, nor did it alter conditioned cue-induced reinstatement. These data indicate that the anxiety-related and stress potentiating qualities of BZ inverse agonism are attenuated in cocaine-experienced animals and do not lead to reinstatement of cocaine-seeking. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Conditional Ablation of Mediator Subunit MED1 (MED1/PPARBP) Gene in Mouse Liver Attenuates Glucocorticoid Receptor Agonist Dexamethasone-Induced Hepatic Steatosis

    PubMed Central

    JIA, YUZHI; VISWAKARMA, NAVIN; FU, TAO; YU, SONGTAO; RAO, M. SAMBASIVA; BORENSZTAJN, JAYME; REDDY, JANARDAN K.

    2009-01-01

    Glucocorticoid receptor (GR) agonist dexamethasone (Dex) induces hepatic steatosis and enhances constitutive androstane receptor (CAR) expression in the liver. CAR is known to worsen hepatic injury in nonalcoholic hepatic steatosis. Because transcription coactivator MED1/PPARBP gene is required for GR- and CAR-mediated transcriptional activation, we hypothesized that disruption of MED1/PPARBP gene in liver cells would result in the attenuation of Dex-induced hepatic steatosis. Here we show that liver-specific disruption of MED1 gene (MED1ΔLiv) improves Dex-induced steatotic phenotype in the liver. In wild-type mice Dex induced severe hepatic steatosis and caused reduction in medium- and short-chain acyl-CoA dehydrogenases that are responsible for mitochondrial β-oxidation. In contrast, Dex did not induce hepatic steatosis in mice conditionally null for hepatic MED1, as it failed to inhibit fatty acid oxidation enzymes in the liver. MED1ΔLiv livers had lower levels of GR-regulated CAR mRNA compared to wild-type mouse livers. Microarray gene expression profiling showed that absence of MED1 affects the expression of the GR-regulated genes responsible for energy metabolism in the liver. These results establish that absence of MED1 in the liver diminishes Dex-induced hepatic steatosis by altering the GR- and CAR-dependent gene functions. PMID:19630272

  12. Central injection of GALR1 agonist M617 attenuates diabetic rat skeletal muscle insulin resistance through the Akt/AS160/GLUT4 pathway.

    PubMed

    Fang, Penghua; Yu, Mei; He, Biao; Guo, Lili; Huang, Xiaoli; Kong, Guimei; Shi, Mingyi; Zhu, Yan; Bo, Ping; Zhang, Zhenwen

    2017-03-01

    Insulin resistance of skeletal muscle plays an important role in the pathogenesis of type 2 diabetes. Galanin, a 29/30-amino-acid neuropeptide, plays multiple biological actions, including anti-diabetic effects. Although recent results of our study showed that administration of galanin could mitigate insulin resistance by promoting glucose transporter 4 (GLUT4) expression and translocation in skeletal muscle of rats, there is no literature available regarding to the effect of type 1 of galanin receptors (GALR1) on insulin resistance in skeletal muscle of type 2 diabetic rats. Herein, we intended to survey the central effect of GALR1 agonist M617 on insulin resistance in skeletal muscle and its underlying mechanisms. We found that the intracerebroventricular injection of M617 increased glucose infusion rates in hyperinsulinemic euglycemic clamp tests, but attenuated the plasma insulin and glucose concentrations of diabetic rats. Furthermore, administration of M617 markedly increased GLUT4 mRNA expression and GLUT4 translocation in skeletal muscle of diabetic rats. Last, perfusion of M617 increased phosphorylated Akt and phosphorylated AS160 levels in the skeletal muscle of diabetic rats. In conclusion, central injection of M617 mitigated insulin resistance of skeletal muscle by enhancing GLUT4 translocation from intracellular pools to plasma membranes via the activation of the Akt/AS160/GLUT4 signaling pathway. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Attenuation of methamphetamine seeking by the mGluR2/3 agonist LY379268 in rats with histories of restricted and escalated self-administration

    PubMed Central

    Kufahl, Peter R.; Watterson, Lucas R.; Nemirovsky, Natali E.; Hood, Lauren E.; Villa, Angel; Halstengard, Casey; Zautra, Nicholas; Olive, M. Foster

    2012-01-01

    Recent findings implicate group II metabotropic glutamate receptors (mGluR2/3) in the reinforcing effects of psychostimulants and have identified these receptors as potential treatment targets for drug addiction. Here, we investigated the effects of mGluR2/3 stimulation on cue- and drug-primed reinstatement in rats with different histories of methamphetamine (METH) self-administration training, under two conditions: 16 daily sessions of short access (90 min/day, ShA), or 8 daily sessions of short access followed by 8 sessions of long access (6 hr/day, LgA). Following self-administration and subsequent extinction training, rats were pretreated with the selective mGluR2/3 agonist LY379268 (variable dose, 0 – 3 mg/kg), exposed to METH-paired cues or a priming injection of METH (1 mg/kg), and tested for reinstatement of METH-seeking behavior. LgA rats self-administered greater amounts of METH during the second half of training, but when pretreated with vehicle, ShA and LgA rats showed cue- and drug-primed reinstatement at equivalent response rates. However, LgA rats demonstrated greater sensitivity to mGluR2/3 stimulation with attenuated responding during cue-induced reinstatement after 0.3 mg/kg and higher doses of LY379268, whereas ShA rats decreased cue-induced reinstatement behavior following 1.0 mg/kg and 3.0 mg/kg LY379268. Additionally, both LgA and ShA rats exhibited decreased METH-primed reinstatement behavior following 0.3 mg/kg and higher doses of LY379268. A separate group of control rats was trained to self-administer sucrose pellets, and demonstrated attenuated cue-induced sucrose-seeking behavior following 1.0 and 3.0 mg/kg LY379268. Together, the results indicate that LY379268 has differential attenuating effects on cue-induced reinstatement behavior in rats with different histories of METH intake. PMID:22659409

  14. Attenuation of methamphetamine seeking by the mGluR2/3 agonist LY379268 in rats with histories of restricted and escalated self-administration.

    PubMed

    Kufahl, Peter R; Watterson, Lucas R; Nemirovsky, Natali E; Hood, Lauren E; Villa, Angel; Halstengard, Casey; Zautra, Nicholas; Olive, M Foster

    2013-03-01

    Recent findings implicate group II metabotropic glutamate receptors (mGluR(2/3)) in the reinforcing effects of psychostimulants and have identified these receptors as potential treatment targets for drug addiction. Here, we investigated the effects of mGluR(2/3) stimulation on cue- and drug-primed reinstatement in rats with different histories of methamphetamine (METH) self-administration training, under two conditions: 16 daily sessions of short access (90 min/day, ShA), or 8 daily sessions of short access followed by 8 sessions of long access (6 h/day, LgA). Following self-administration and subsequent extinction training, rats were pretreated with the selective mGluR(2/3) agonist LY379268 (variable dose, 0-3 mg/kg), exposed to METH-paired cues or a priming injection of METH (1 mg/kg), and tested for reinstatement of METH-seeking behavior. LgA rats self-administered greater amounts of METH during the second half of training, but when pretreated with vehicle, ShA and LgA rats showed cue- and drug-primed reinstatement at equivalent response rates. However, LgA rats demonstrated greater sensitivity to mGluR(2/3) stimulation with attenuated responding during cue-induced reinstatement after 0.3 mg/kg and higher doses of LY379268, whereas ShA rats decreased cue-induced reinstatement behavior following 1.0 mg/kg and 3.0 mg/kg LY379268. Additionally, both LgA and ShA rats exhibited decreased METH-primed reinstatement behavior following 0.3 mg/kg and higher doses of LY379268. A separate group of control rats was trained to self-administer sucrose pellets, and demonstrated attenuated cue-induced sucrose-seeking behavior following 1.0 and 3.0 mg/kg LY379268. Together, the results indicate that LY379268 has differential attenuating effects on cue-induced reinstatement behavior in rats with different histories of METH intake. This article is part of a Special Issue entitled 'Metabotropic Glutamate Receptors'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Orthopedic surgery and bone fracture pain are both significantly attenuated by sustained blockade of nerve growth factor

    PubMed Central

    Majuta, Lisa A.; Longo, Geraldine; Fealk, Michelle N.; McCaffrey, Gwen; Mantyh, Patrick W.

    2015-01-01

    The number of patients suffering from postoperative pain due to orthopedic surgery and bone fracture is projected to dramatically increase because the human life span, weight, and involvement in high-activity sports continue to rise worldwide. Joint replacement or bone fracture frequently results in skeletal pain that needs to be adequately controlled for the patient to fully participate in needed physical rehabilitation. Currently, the 2 major therapies used to control skeletal pain are nonsteroidal anti-inflammatory drugs and opiates, both of which have significant unwanted side effects. To assess the efficacy of novel therapies, mouse models of orthopedic and fracture pain were developed and evaluated here. These models, orthopedic surgery pain and bone fracture pain, resulted in skeletal pain–related behaviors that lasted 3 weeks and 8 to 10 weeks, respectively. These skeletal pain behaviors included spontaneous and palpation-induced nocifensive behaviors, dynamic weight bearing, limb use, and voluntary mechanical loading of the injured hind limb. Administration of anti–nerve growth factor before orthopedic surgery or after bone fracture attenuated skeletal pain behaviors by 40% to 70% depending on the end point being assessed. These data suggest that nerve growth factor is involved in driving pain due to orthopedic surgery or bone fracture. These animal models may be useful in developing an understanding of the mechanisms that drive postoperative orthopedic and bone fracture pain and the development of novel therapies to treat these skeletal pains. PMID:25599311

  16. Orthopedic surgery and bone fracture pain are both significantly attenuated by sustained blockade of nerve growth factor.

    PubMed

    Majuta, Lisa A; Longo, Geraldine; Fealk, Michelle N; McCaffrey, Gwen; Mantyh, Patrick W

    2015-01-01

    The number of patients suffering from postoperative pain due to orthopedic surgery and bone fracture is projected to dramatically increase because the human life span, weight, and involvement in high-activity sports continue to rise worldwide. Joint replacement or bone fracture frequently results in skeletal pain that needs to be adequately controlled for the patient to fully participate in needed physical rehabilitation. Currently, the 2 major therapies used to control skeletal pain are nonsteroidal anti-inflammatory drugs and opiates, both of which have significant unwanted side effects. To assess the efficacy of novel therapies, mouse models of orthopedic and fracture pain were developed and evaluated here. These models, orthopedic surgery pain and bone fracture pain, resulted in skeletal pain-related behaviors that lasted 3 weeks and 8 to 10 weeks, respectively. These skeletal pain behaviors included spontaneous and palpation-induced nocifensive behaviors, dynamic weight bearing, limb use, and voluntary mechanical loading of the injured hind limb. Administration of anti-nerve growth factor before orthopedic surgery or after bone fracture attenuated skeletal pain behaviors by 40% to 70% depending on the end point being assessed. These data suggest that nerve growth factor is involved in driving pain due to orthopedic surgery or bone fracture. These animal models may be useful in developing an understanding of the mechanisms that drive postoperative orthopedic and bone fracture pain and the development of novel therapies to treat these skeletal pains.

  17. Bone Marrow-Derived c-kit+ Cells Attenuate Neonatal Hyperoxia-Induced Lung Injury

    PubMed Central

    Ramachandran, Shalini; Suguihara, Cleide; Drummond, Shelley; Chatzistergos, Konstantinos; Klim, Jammie; Torres, Eneida; Huang, Jian; Hehre, Dorothy; Rodrigues, Claudia O.; McNiece, Ian K.; Hare, Joshua M.; Young, Karen C.

    2016-01-01

    Recent studies suggest that bone marrow (BM)-derived stem cells have therapeutic efficacy in neonatal hyperoxia-induced lung injury (HILI). c-kit, a tyrosine kinase receptor that regulates angiogenesis, is expressed on several populations of BM-derived cells. Preterm infants exposed to hyperoxia have decreased lung angiogenesis. Here we tested the hypothesis that administration of BM-derived c-kit+ cells would improve angiogenesis in neonatal rats with HILI. To determine whether intratracheal (IT) administration of BM-derived c-kit+ cells attenuates neonatal HILI, rat pups exposed to either normobaric normoxia (21% O2) or hyperoxia (90% O2) from postnatal day (P) 2 to P15 were randomly assigned to receive either IT BM-derived green fluorescent protein (GFP)+ c-kit− cells (PL) or BM-derived GFP+ c-kit+ cells on P8. The effect of cell therapy on lung angiogenesis, alveolarization, pulmonary hypertension, vascular remodeling, cell proliferation, and apoptosis was determined at P15. Cell engraftment was determined by GFP immunostaining. Compared to PL, the IT administration of BM-derived c-kit+ cells to neonatal rodents with HILI improved alveolarization as evidenced by increased lung septation and decreased mean linear intercept. This was accompanied by an increase in lung vascular density, a decrease in lung apoptosis, and an increase in the secretion of proangiogenic factors. There was no difference in pulmonary vascular remodeling or the degree of pulmonary hypertension. Confocal microscopy demonstrated that 1% of total lung cells were GFP+ cells. IT administration of BM-derived c-kit+ cells improves lung alveolarization and angiogenesis in neonatal HILI, and this may be secondary to an improvement in the lung angiogenic milieu. PMID:23759597

  18. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic analysis of regenerated bone

    NASA Astrophysics Data System (ADS)

    Benetti, Carolina; Kazarain, Sergei G.; Alves, Marco A. V.; Blay, Alberto; Correa, Luciana; Zezell, Denise M.

    2014-03-01

    The cutting of bone is routinely required in medical procedures, especially in dental applications. In such cases, bone regeneration and new bone quality can determine the success of the treatment. This study investigated the main spectral differences of undamaged and healed bone using the ATR-FTIR spectroscopy technique. Three rabbits were submitted to a surgical procedure; a small piece of bone (3x3 mm2) was removed from both sides of their jaws using a high speed drill. After 15 days, the rabbits were euthanized and the jaws were removed. A bone slice was cut from each side of the jaw containing regions of undamaged and newly formed bone, resulting in six samples which were polished for spectroscopic comparison. The samples were analyzed by FTIR spectroscopy using a diamond ATR accessory. Spectral characteristics were compared and particular attention was paid to the proportion of phosphate to amide I bands and the width of the phosphate band. The results show that the ratio of phosphate to amide I is smaller in new bone tissue than in the undamaged bone, indicating a higher organic content in the newly formed bone. The analysis of the width of the phosphate band suggests a crystallinity difference between both tissues, since the width was higher in the new bone than in the natural bone. These results suggest that the differences observed in bone aging processes by FTIR spectroscopic can be applied to the study of healing processes.

  19. PPARα agonist fenofibrate attenuates TNF-α-induced CD40 expression in 3T3-L1 adipocytes via the SIRT1-dependent signaling pathway

    SciTech Connect

    Wang, Weirong; Lin, Qinqin; Lin, Rong; Zhang, Jiye; Ren, Feng; Zhang, Jianfeng; Ji, Meixi; Li, Yanxiang

    2013-06-10

    The ligand-activated transcription factor peroxisome proliferator-activated receptor-α (PPARα) participates in the regulation of cellular inflammation. More recent studies indicated that sirtuin1 (SIRT1), a NAD{sup +}-dependent deacetylase, regulates the inflammatory response in adipocytes. However, whether the role of PPARα in inflammation is mediated by SIRT1 remains unclear. In this study, we aimed to determine the effect of PPARα agonist fenofibrate on the expressions of SIRT1 and pro-inflammatory cytokine CD40 and underlying mechanisms in 3T3-L1 adipocytes. We found that fenofibrate inhibited CD40 expression and up-regulated SIRT1 expression in tumor necrosis factor-α (TNF-α)-stimulated adipocytes, and these effects of fenofibrate were reversed by PPARα antagonist GW6471. Moreover, SIRT1 inhibitors sirtinol/nicotinamide (NAM) or knockdown of SIRT1 could attenuate the effect of fenofibrate on TNF-α-induced CD40 expression in adipocytes. Importantly, NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) augmented the effect of fenofibrate on CD40 expression in adipocytes. Further study found that fenofibrate decreased the expression of acetylated-NF-κB p65 (Ac-NF-κB p65) in TNF-α-stimulated adipocytes, and the effect of fenofibrate was abolished by SIRT1 inhibition. In addition, fenofibrate up-regulated SIRT1 expression through AMPK in TNF-α-stimulated adipocytes. Taken together, these findings indicate that PPARα agonist fenofibrate inhibits TNF-α-induced CD40 expression in 3T3-L1 adipocytes via the SIRT1-dependent signaling pathway. -- Highlights: • Fenofibrate up-regulates SIRT1 expression in TNF-α-stimulated adipocytes. • Fenofibrate inhibits CD40 expression through SIRT1 in adipocytes. • The effects of fenofibrate on CD40 and SIRT1 expressions are dependent on PPARα. • Fenofibrate inhibits CD40 expression via SIRT1-dependent deacetylation of NF-κB. • Fenofibrate increases SIRT1 expression through PPARα and AMPK in adipocytes.

  20. The glucagon-like peptide-1 receptor agonist, liraglutide, attenuates the progression of overt diabetic nephropathy in type 2 diabetic patients.

    PubMed

    Imamura, Shigeki; Hirai, Keiji; Hirai, Aizan

    2013-01-01

    Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Glucagon-like peptide-1 (GLP-1) is one of the incretins, gut hormones released from the intestine in response to food intake. GLP-1 receptor (GLP-1R) agonists have been used to treat type 2 diabetes. Here, we studied the effect of the administration of a GLP-1R agonist, liraglutide, on proteinuria and the progression of overt DN in type 2 diabetic patients. Twenty-three type 2 diabetic patients with overt DN, who had already been treated with blockade of renin-angiotensin system under dietary sodium restriction, were given liraglutide for a period of 12 months. Treatment with liraglutide caused a significant decrease in HbA1c from 7.4 ± 0.2% to 6.9 ± 0.3% (p = 0.04), and in body mass index (BMI) from 27.6 ± 0.9 kg/m² to 26.5 ± 0.8 kg/m² after 12 months (p < 0.001), while systolic blood pressure did not change. The progression of DN was determined as the rate of decline in estimated glomerular filtration rate (eGFR). The 12-month administration of liraglutide caused a significant decrease in proteinuria from 2.53 ± 0.48 g/g creatinine to 1.47 ± 0.28 g/g creatinine (p = 0.002). The administration of liraglutide also substantially diminished the rate of decline in eGFR from 6.6 ± 1.5 mL/min/1.73 m²/year to 0.3 ± 1.9 mL/min/1.73 m²/year (p = 0.003). Liraglutide can be used not only for reducing HbA1c and BMI, but also for attenuating the progression of nephropathy in type 2 diabetic patients.

  1. AMN082, a metabotropic glutamate receptor 7 allosteric agonist, attenuates locomotor sensitization and cross-sensitization induced by cocaine and morphine in mice.

    PubMed

    Jenda, M; Gawel, K; Marszalek, M; Komsta, L; Kotlinska, J H

    2015-03-03

    Previous studies have indicated that metabotropic glutamate receptors 7 (mGluR7s) are involved in drug addiction. However, the role of these receptors in drug-induced behavioral sensitization is unknown. The aim of the present study was to determine whether systemic injection of AMN082, a selective mGluR7 allosteric agonist, reduces the cocaine- and morphine-induced hyperactivity and the development and expression of locomotor sensitization, and also affects the reciprocal cross-sensitization to the stimulant effect of cocaine and morphine in mice. AMN082 (1.25-10.0 mg/kg, i.p.) did not have an impact on locomotion of naive mice and did not affect the acute cocaine- or morphine-induced hyperactivity, except the dose of 10 mg/kg that suppressed the locomotor effect of both drugs. Repeated exposure to cocaine or morphine (10 mg/kg, 5× every 3 days) gradually increased locomotion during induction of sensitization and after 4 (cocaine) or 7 day (morphine) withdrawal phase when challenged with cocaine (10 mg/kg, i.p.) or morphine (10 mg/kg, i.p.) on day 17 or 20, respectively. Pretreatment of animals with the lower doses of AMN082 (1.25-5.0 mg/kg, i.p.), 30 min before every cocaine or morphine injection during repeated drug administration or before cocaine or morphine challenge, dose-dependently attenuated the development, as well as the expression of cocaine or morphine locomotor sensitization. AMN082 also inhibited the reciprocal cross-sensitization between these drugs. Prior to administration of MMPIP (10 mg/kg, i.p.), a selective mGluR7 antagonist reversed the inhibitory effect of AMN082 on the development or expression of cocaine or morphine sensitization. These data indicate that AMN082 attenuated the development and expression of cocaine and morphine sensitization, and the reciprocal cross-sensitization via a mechanism that involves mGluR7s. Thus, AMN082 might have therapeutic implications not only in the treatment of cocaine or opioid addiction but also in the

  2. Putative Dopamine Agonist (KB220Z) Attenuates Lucid Nightmares in PTSD Patients: Role of Enhanced Brain Reward Functional Connectivity and Homeostasis Redeeming Joy

    PubMed Central

    McLaughlin, Thomas; Blum, Kenneth; Oscar-Berman, Marlene; Febo, Marcelo; Agan, Gozde; Fratantonio, James L.; Simpatico, Thomas; Gold, Mark S.

    2015-01-01

    Background Lucid dreams are frequently pleasant and training techniques have been developed to teach dreamers to induce them. In addition, the induction of lucid dreams has also been used as a way to ameliorate nightmares. On the other hand, lucid dreams may be associated with psychiatric conditions, including Post-Traumatic Stress Disorder (PTSD) and Reward Deficiency Syndrome-associated diagnoses. In the latter conditions, lucid dreams can assume an unpleasant and frequently terrifying character. Case Presentations We present two cases of dramatic alleviation of terrifying lucid dreams in patients with PTSD. In the first case study, a 51-year-old, obese woman, diagnosed with PTSD and depression, had attempted suicide and experienced terrifying lucid nightmares linked to sexual/physical abuse from early childhood by family members including her alcoholic father. Her vivid “bad dreams” remained refractory in spite of 6 months of treatment with Dialectical Behavioral Therapy (DBT) and standard pharmaceutical agents which included prazosin, clonidie and Adderall. The second 39-year-old PTSD woman patient had also suffered from lucid nightmares. Results The medication visit notes reveal changes in the frequency, intensity and nature of these dreams after the complex putative dopamine agonist KB220Z was added to the first patient’s regimen. The patient reported her first experience of an extended period of happy dreams. The second PTSD patient, who had suffered from lucid nightmares, was administered KB220Z to attenuate methadone withdrawal symptoms and incidentally reported dreams full of happiness and laughter. Conclusions These cases are discussed with reference to the known effects of KB220Z including enhanced dopamine homeostasis and functional connectivity of brain reward circuitry in rodents and humans. Their understanding awaits intensive investigation involving large-population, double-blinded studies. PMID:26132915

  3. Palmitic acid-induced apoptosis in pancreatic β-cells is increased by liver X receptor agonist and attenuated by eicosapentaenoate.

    PubMed

    Liang, Huasheng; Zhong, Yuhua; Zhou, Shaobi; Li, Qingdi Quentin

    2011-01-01

    Saturated fatty acids are implicated in the development of diabetes via the impairment of pancreatic islet β-cell viability and function. Liver X receptors (LXRs) and eicosapentaenoate (EPA) are known regulators of fatty acid metabolism. However, their roles in the pathogenesis of diabetes remain incompletely understood. The aim of this study was to determine the effects of EPA and the LXR agonist T0901317 on saturated fatty acid (palmitic acid)-induced apoptosis in the insulinoma β-cell line INS-1, a model for insulin-secreting β-cells. T0901317 significantly promoted palmitic acid-induced apoptotic cell death in the INS-1 cells. Consistent with these results, caspase-3 activity and BAX and sterol regulatory element binding protein-1c (SREBP-1c) mRNA levels were markedly increased in INS-1 cells co-administered palmitic acid and T0901317. The production of reactive oxygen species was considerably higher in the cells cultured concurrently with T0901317 and palmitic acid than in the cells incubated with either agent alone. EPA treatment attenuated the cellular death promoted by palmitic acid and T0901317 in the INS-1 cells, disclosing a possible mediating mechanism involving the inhibition of SREBP-1c. Finally, T0901317 up-regulated the palmitic acid-induced expression of p27(KIP1), transforming growth factor beta 1, and SMAD3 proteins in INS-1 cells. These results demonstrate that palmitic acid-induced apoptosis in β-cells is enhanced by T0901317 via the activation of LXRs and is blocked by EPA via the inhibition of SREBP-1c, suggesting that the regulation of lipogenesis and lipotoxicity affecting pancreatic β-cell viability and insulin production may be a unique strategy for diabetes therapy.

  4. Transdermal Patch of Rotigotine Attenuates Freezing of Gait in Patients with Parkinson's Disease: An Open-Label Comparative Study of Three Non-Ergot Dopamine Receptor Agonists

    PubMed Central

    Ikeda, Ken; Hirayama, Takehisa; Takazawa, Takanori; Kawabe, Kiyokazu; Iwasaki, Yasuo

    2016-01-01

    Objective Parkinson's disease (PD) is characterized by the progressive degeneration of the nigrostriatal dopaminergic neurons. Rotigotine is a non-ergot dopamine receptor agonist (DA). Its transdermal patch maintains the effective concentrations for 24 hours. Freezing of gait (FOG) is a common and devastating symptom in PD patients. Little is known about therapeutic effects of rotigotine on FOG in PD patients. Herein we compared how three non-ergot DAs of rotigotine, pramipexole LA and ropinirole CR influence FOG, besides classical motor deficits in PD patients. Methods Rotigotine (maintenance doses of 9-27 mg/day) was administered in 51 patients, 36 patients received pramipexole LA (1.5-4.5 mg/day) and 35 patients received ropinirole CR (8-16 mg/day). The Unified PD Rating Scale (UPDRS) parts I-IV, FOG questionnaire (16 items) and wearing off time were examined from baseline to 7 months after DA administration. UPDRS parts I-IV were evaluated during on time and FOG was recorded during off time if patients experienced wearing off. Results A total of 111 patients completed the study. UPDRS parts II-III scores and wearing off time were significantly reduced after each DA treatment compared to baseline. FOG was found in 54 patients (49%). Most patients developed FOG during off time only. FOG scores were significantly decreased at 2 months after rotigotine treatment whereas pramipexole LA and ropinirole treatment did not alter FOG scores. Conclusion The present study indicates that transdermal patch of rotigotine attenuated the FOG off time. The similar binding affinities to dopamine receptors between rotigotine and dopamine, and 24 hours steady hemodynamics could contribute to the therapeutic mechanism of rotigotine on FOG in PD patients with wearing off. PMID:27725534

  5. Putative dopamine agonist (KB220Z) attenuates lucid nightmares in PTSD patients: role of enhanced brain reward functional connectivity and homeostasis redeeming joy.

    PubMed

    McLaughlin, Thomas; Blum, Kenneth; Oscar-Berman, Marlene; Febo, Marcelo; Agan, Gozde; Fratantonio, James L; Simpatico, Thomas; Gold, Mark S

    2015-06-01

    Lucid dreams are frequently pleasant and training techniques have been developed to teach dreamers to induce them. In addition, the induction of lucid dreams has also been used as a way to ameliorate nightmares. On the other hand, lucid dreams may be associated with psychiatric conditions, including Post-Traumatic Stress Disorder (PTSD) and Reward Deficiency Syndrome-associated diagnoses. In the latter conditions, lucid dreams can assume an unpleasant and frequently terrifying character. We present two cases of dramatic alleviation of terrifying lucid dreams in patients with PTSD. In the first case study, a 51-year-old, obese woman, diagnosed with PTSD and depression, had attempted suicide and experienced terrifying lucid nightmares linked to sexual/physical abuse from early childhood by family members including her alcoholic father. Her vivid "bad dreams" remained refractory in spite of 6 months of treatment with Dialectical Behavioral Therapy (DBT) and standard pharmaceutical agents which included prazosin, clonidie and Adderall. The second 39-year-old PTSD woman patient had also suffered from lucid nightmares. The medication visit notes reveal changes in the frequency, intensity and nature of these dreams after the complex putative dopamine agonist KB220Z was added to the first patient's regimen. The patient reported her first experience of an extended period of happy dreams. The second PTSD patient, who had suffered from lucid nightmares, was administered KB220Z to attenuate methadone withdrawal symptoms and incidentally reported dreams full of happiness and laughter. These cases are discussed with reference to the known effects of KB220Z including enhanced dopamine homeostasis and functional connectivity of brain reward circuitry in rodents and humans. Their understanding awaits intensive investigation involving large-population, double-blinded studies.

  6. Inhibition of SDF-1α/CXCR4 Signalling in Subchondral Bone Attenuates Post-Traumatic Osteoarthritis

    PubMed Central

    Dong, Yonghui; Liu, Hui; Zhang, Xuejun; Xu, Fei; Qin, Liang; Cheng, Peng; Huang, Hui; Guo, Fengjing; Yang, Qing; Chen, Anmin

    2016-01-01

    Previous studies showed that SDF-1α is a catabolic factor that can infiltrate cartilage, decrease proteoglycan content, and increase MMP-13 activity. Inhibiting the SDF-1α/CXCR4 signalling pathway can attenuate the pathogenesis of osteoarthritis (OA). Recent studies have also shown that SDF-1α enhances chondrocyte proliferation and maturation. These results appear to be contradictory. In the current study, we used a destabilisation OA animal model to investigate the effects of SDF-1α/CXCR4 signalling in the tibial subchondral bone and the OA pathological process. Post-traumatic osteoarthritis (PTOA) mice models were prepared by transecting the anterior cruciate ligament (ACLT), or a sham surgery was performed, in a total of 30 mice. Mice were treated with phosphate buffer saline (PBS) or AMD3100 (an inhibitor of CXCR4) and sacrificed at 30 days post ACLT or sham surgery. Tibial subchondral bone status was quantified by micro-computed tomography (μCT). Knee-joint histology was analysed to examine the articular cartilage and joint degeneration. The levels of SDF-1α and collagen type I c-telopeptidefragments (CTX-I) were quantified by ELISA. Bone marrow mononuclear cells (BMMCs) were used to clarify the effects of SDF-1α on osteoclast formation and activity in vivo. μCT analysis revealed significant loss of trabecular bone from tibial subchondral bone post-ACLT, which was effectively prevented by AMD3100. AMD3100 could partially prevent bone loss and articular cartilage degeneration. Serum biomarkers revealed an increase in SDF-1α and bone resorption, which were also reduced by AMD3100. SDF-1α can promote osteoclast formation and the expression oftartrate resistant acid phosphatase (TRAP), cathepsin K (CK), and matrix metalloproteinase (MMP)-9 in osteoclasts by activating the MAPK pathway, including ERK and p38, but not JNK. In conclusion, inhibition of SDF-1α/CXCR4signalling was able to prevent trabecular bone loss and attenuated cartilage degeneration in

  7. Bone fracture risk is not associated with the use of glucagon-like peptide-1 receptor agonists: a population-based cohort analysis.

    PubMed

    Driessen, Johanna H M; Henry, Ronald M A; van Onzenoort, Hein A W; Lalmohamed, Arief; Burden, Andrea M; Prieto-Alhambra, Daniel; Neef, Cees; Leufkens, Hubert G M; de Vries, Frank

    2015-08-01

    Glucagon-like Peptide-1 receptor agonists (GLP1-ra) are a relatively new class of anti-hyperglycemic drugs which may positively affect bone metabolism and thereby decrease (osteoporotic) bone fracture risk. Data on the effect of GLP1-ra on fracture risk are scarce and limited to clinical trial data only. The aim of this study was to investigate, in a population-based cohort, the association between the use of GLP1-ra and bone fracture risk. We conducted a population-based cohort study, with the use of data from the Clinical Practice Research Datalink (CPRD) database (2007-2012). The study population (N = 216,816) consisted of all individuals with type 2 diabetes patients with at least one prescription for a non-insulin anti-diabetic drug and were over 18 years of age. Cox proportional hazards models were used to estimate the hazard ratio of fracture in GLP1-ra users versus never-GLP1-ra users. Time-dependent adjustments were made for age, sex, lifestyle, comorbidity and the use of other drugs. There was no decreased risk of fracture with current use of GLP1-ra compared to never-GLP1-ra use (adjusted HR 0.99, 95 % CI 0.82-1.19). Osteoporotic fracture risk was also not decreased by current GLP1-ra use (adjusted HR 0.97; 95 % CI 0.72-1.32). In addition, stratification according to cumulative dose did not show a decreased bone fracture risk with increasing cumulative GLP1-ra dose. We showed in a population-based cohort study that GLP1-ra use is not associated with a decreased bone fracture risk compared to users of other anti-hyperglycemic drugs. Future research is needed to elucidate the potential working mechanisms of GLP1-ra on bone.

  8. Propranolol Attenuates Risperidone-Induced Trabecular Bone Loss in Female Mice.

    PubMed

    Motyl, Katherine J; DeMambro, Victoria E; Barlow, Deborah; Olshan, David; Nagano, Kenichi; Baron, Roland; Rosen, Clifford J; Houseknecht, Karen L

    2015-07-01

    Atypical antipsychotic (AA) drugs cause significant metabolic side effects, and clinical data are emerging that demonstrate increased fracture risk and bone loss after treatment with the AA, risperidone (RIS). The pharmacology underlying the adverse effects on bone is unknown. However, RIS action in the central nervous system could be responsible because the sympathetic nervous system (SNS) is known to uncouple bone remodeling. RIS treatment in mice significantly lowered trabecular bone volume fraction (bone volume/total volume), owing to increased osteoclast-mediated erosion and reduced osteoblast-mediated bone formation. Daytime energy expenditure was also increased and was temporally associated with the plasma concentration of RIS. Even a single dose of RIS transiently elevated expression of brown adipose tissue markers of SNS activity and thermogenesis, Pgc1a and Ucp1. Rankl, an osteoclast recruitment factor regulated by the SNS, was also increased 1 hour after a single dose of RIS. Thus, we inferred that bone loss from RIS was regulated, at least in part, by the SNS. To test this, we administered RIS or vehicle to mice that were also receiving the nonselective β-blocker propranolol. Strikingly, RIS did not cause any changes in trabecular bone volume/total volume, erosion, or formation while propranolol was present. Furthermore, β2-adrenergic receptor null (Adrb2(-/-)) mice were also protected from RIS-induced bone loss. This is the first report to demonstrate SNS-mediated bone loss from any AA. Because AA medications are widely prescribed, especially to young adults, clinical studies are needed to assess whether β-blockers will prevent bone loss in this vulnerable population.

  9. Adverse effects of smoking on peak bone mass may be attenuated by higher body mass index in young female smokers.

    PubMed

    Callréus, Mattias; McGuigan, Fiona; Akesson, Kristina

    2013-12-01

    Smoking is associated with postmenopausal bone loss and fracture, but the effect of smoking on bone in younger women is unclear. Peak bone mass is an important determinant for fracture risk; therefore, our aim was to evaluate the association between smoking and bone mass in 25-year-old women, specifically the influence of daily cigarette consumption and total exposure, duration, age at starting smoking, and time since smoking cessation on bone density and fracture risk. Smoking and bone mineral density (BMD) data were available for 1,054 women from the PEAK-25 cohort. Analyses comparing current smokers with women who never smoked were performed using number of cigarettes per day, pack-years, smoking duration, age smoking started, and, for former smokers, age at quitting. BMD did not differ between never, former, and current smokers; and the relative fracture risk in smokers was not significant (relative risk [RR] = 1.2, 95 % confidence interval 0.8-1.9). Among current smokers, BMD decreased with a dose response as cigarette consumption increased (femoral neck p = 0.037). BMD was not significantly lower in young women who had smoked for long duration or started smoking early (p = 0.07-0.64); long duration and early start were associated with higher body mass index (BMI; p = 0.038). Lower BMD persisted up to 24 months after smoking cessation (p = 0.027-0.050), becoming comparable to never-smokers after 24 months. Hip BMD was negatively associated with smoking and dose-dependent on cigarette consumption. Smoking duration was not associated with BMD, although young women with a long smoking history had higher BMI, which might attenuate the adverse effects from smoking.

  10. Impaired differentiation of macrophage lineage cells attenuates bone remodeling and inflammatory angiogenesis in Ndrg1 deficient mice.

    PubMed

    Watari, Kosuke; Shibata, Tomohiro; Nabeshima, Hiroshi; Shinoda, Ai; Fukunaga, Yuichi; Kawahara, Akihiko; Karasuyama, Kazuyuki; Fukushi, Jun-Ichi; Iwamoto, Yukihide; Kuwano, Michihiko; Ono, Mayumi

    2016-01-18

    N-myc downstream regulated gene 1 (NDRG1) is a responsible gene for a hereditary motor and sensory neuropathy-Lom (Charcot-Marie-Tooth disease type 4D). This is the first study aiming to assess the contribution of NDRG1 to differentiation of macrophage lineage cells, which has important implications for bone remodeling and inflammatory angiogenesis. Ndrg1 knockout (KO) mice exhibited abnormal curvature of the spine, high trabecular bone mass, and reduced number of osteoclasts. We observed that serum levels of macrophage colony-stimulating factor (M-CSF) and macrophage-related cytokines were markedly decreased in KO mice. Differentiation of bone marrow (BM) cells into osteoclasts, M1/M2-type macrophages and dendritic cells was all impaired. Furthermore, KO mice also showed reduced tumor growth and angiogenesis by cancer cells, accompanied by decreased infiltration of tumor-associated macrophages. The transfer of BM-derived macrophages from KO mice into BM-eradicated wild type (WT) mice induced much less tumor angiogenesis than observed in WT mice. Angiogenesis in corneas in response to inflammatory stimuli was also suppressed with decreased infiltration of macrophages. Taken together, these results indicate that NDRG1 deficiency attenuates the differentiation of macrophage lineage cells, suppressing bone remodeling and inflammatory angiogenesis. This study strongly suggests the crucial role of NDRG1 in differentiation process for macrophages.

  11. Green tea polyphenols attenuate deterioration of bone microarchitecture in female rats with systemic chronic inflammation

    USDA-ARS?s Scientific Manuscript database

    Introduction: Our previous study demonstrated that green tea polyphenols (GTP) benefit bone health in female rats with chronic inflammation, because of GTP’s antioxidant capacity. The current study further evaluates whether GTP can restore bone microstructure along with related mechanism in rats wit...

  12. Inter-observer and inter-examination variability of manual vertebral bone attenuation measurements on computed tomography.

    PubMed

    Pompe, Esther; de Jong, Pim A; de Jong, Werner U; Takx, Richard A P; Eikendal, Anouk L M; Willemink, Martin J; Oudkerk, Matthijs; Budde, Ricardo P J; Lammers, Jan-Willem J; Mohamed Hoesein, Firdaus A A

    2016-09-01

    To determine inter-observer and inter-examination variability of manual attenuation measurements of the vertebrae in low-dose unenhanced chest computed tomography (CT). Three hundred and sixty-seven lung cancer screening trial participants who underwent baseline and repeat unenhanced low-dose CT after 3 months because of an indeterminate lung nodule were included. The CT attenuation value of the first lumbar vertebrae (L1) was measured in all CTs by one observer to obtain inter-examination reliability. Six observers performed measurements in 100 randomly selected CTs to determine agreement with limits of agreement and Bland-Altman plots and reliability with intraclass correlation coefficients (ICCs). Reclassification analyses were performed using a threshold of 110 HU to define osteoporosis. Inter-examination reliability was excellent with an ICC of 0.92 (p < 0.001). Inter-examination limits of agreement ranged from -26 to 28 HU with a mean difference of 1 ± 14 HU. Inter-observer reliability ICCs ranged from 0.70 to 0.91. Inter-examination variability led to 11.2 % reclassification of participants and inter-observer variability led to 22.1 % reclassification. Vertebral attenuation values can be manually quantified with good to excellent inter-examination and inter-observer reliability on unenhanced low-dose chest CT. This information is valuable for early detection of osteoporosis on low-dose chest CT. • Vertebral attenuation values can be manually quantified on low-dose unenhanced CT reliably. • Vertebral attenuation measurements may be helpful in detecting subclinical low bone density. • This could become of importance in the detection of osteoporosis.

  13. Correction of quantification errors in pelvic and spinal lesions caused by ignoring higher photon attenuation of bone in [{sup 18}F]NaF PET/MR

    SciTech Connect

    Schramm, Georg Maus, Jens; Hofheinz, Frank; Petr, Jan; Lougovski, Alexandr; Beuthien-Baumann, Bettina; Oehme, Liane; Platzek, Ivan; Hoff, Jörg van den

    2015-11-15

    Purpose: MR-based attenuation correction (MRAC) in routine clinical whole-body positron emission tomography and magnetic resonance imaging (PET/MRI) is based on tissue type segmentation. Due to lack of MR signal in cortical bone and the varying signal of spongeous bone, standard whole-body segmentation-based MRAC ignores the higher attenuation of bone compared to the one of soft tissue (MRAC{sub nobone}). The authors aim to quantify and reduce the bias introduced by MRAC{sub nobone} in the standard uptake value (SUV) of spinal and pelvic lesions in 20 PET/MRI examinations with [{sup 18}F]NaF. Methods: The authors reconstructed 20 PET/MR [{sup 18}F]NaF patient data sets acquired with a Philips Ingenuity TF PET/MRI. The PET raw data were reconstructed with two different attenuation images. First, the authors used the vendor-provided MRAC algorithm that ignores the higher attenuation of bone to reconstruct PET{sub nobone}. Second, the authors used a threshold-based algorithm developed in their group to automatically segment bone structures in the [{sup 18}F]NaF PET images. Subsequently, an attenuation coefficient of 0.11 cm{sup −1} was assigned to the segmented bone regions in the MRI-based attenuation image (MRAC{sub bone}) which was used to reconstruct PET{sub bone}. The automatic bone segmentation algorithm was validated in six PET/CT [{sup 18}F]NaF examinations. Relative SUV{sub mean} and SUV{sub max} differences between PET{sub bone} and PET{sub nobone} of 8 pelvic and 41 spinal lesions, and of other regions such as lung, liver, and bladder, were calculated. By varying the assigned bone attenuation coefficient from 0.11 to 0.13 cm{sup −1}, the authors investigated its influence on the reconstructed SUVs of the lesions. Results: The comparison of [{sup 18}F]NaF-based and CT-based bone segmentation in the six PET/CT patients showed a Dice similarity of 0.7 with a true positive rate of 0.72 and a false discovery rate of 0.33. The [{sup 18}F]NaF-based bone

  14. Nardosinone Suppresses RANKL-Induced Osteoclastogenesis and Attenuates Lipopolysaccharide-Induced Alveolar Bone Resorption

    PubMed Central

    Niu, Chenguang; Xiao, Fei; Yuan, Keyong; Hu, XuChen; Lin, Wenzhen; Ma, Rui; Zhang, Xiaoling; Huang, Zhengwei

    2017-01-01

    Periodontitis is a chronic inflammatory disease that damages the integrity of the tooth-supporting tissues, known as the periodontium, and comprising the gingiva, periodontal ligament and alveolar bone. In this study, the effects of nardosinone (Nd) on bone were tested in a model of lipopolysaccharide (LPS)-induced alveolar bone loss, and the associated mechanisms were elucidated. Nd effectively suppressed LPS-induced alveolar bone loss and reduced osteoclast (OC) numbers in vivo. Nd suppressed receptor activator of nuclear factor-κB ligand (RANKL)-mediated OC differentiation, bone resorption, and F-actin ring formation in a dose-dependent manner. Further investigation revealed that Nd suppressed osteoclastogenesis by suppressing the ERK and JNK signaling pathways, scavenging reactive oxygen species, and suppressing the activation of PLCγ2 that consequently affects the expression and/or activity of the OC-specific transcription factors, c-Fos and nuclear factor of activated T-cells cytoplasmic 1 (NFATc1). In addition, Nd significantly reduced the expression of OC-specific markers in mouse bone marrow-derived pre-OCs, including c-Fos, cathepsin K (Ctsk), VATPase d2, and Nfatc1. Collectively, these findings suggest that Nd has beneficial effects on bone, and the suppression of OC number implies that the effect is exerted directly on osteoclastogenesis. PMID:28955231

  15. Comparison of bone mineral loss by combined androgen block agonist versus GnRH in patients with prostate cancer: A 12 month-prospective observational study.

    PubMed

    Kim, Sung Han; Joung, Jae Young; Kim, Sohee; Rha, Koon Ho; Kim, Hyeong Gon; Kwak, Cheol; Lee, Ji Youl; Jeon, Seong Soo; Hong, Sung Kyu; Jeong, Hyeon; Jo, Moon Ki; You, Dalsan; Jeong, In Gab; Hong, Jun Hyuk; Kim, Choung-Soo

    2017-03-06

    The multi-centre, prospective, observational study was designed to examine the efficacy of continuous combined androgen block (CAB) vs. GnRH agonist monotherapy in terms of bone mineral density (BMD) change during 12 months post-androgen deprivation therapy (ADT) in Asian prostate cancer patients. Multiple regression analysis and estimated the 10-year probability of major fractures among the patients with Fracture Risk Assessment Tool were conducted to investigate the underlying factors affecting BMD. Paired t-test to evaluate the change of BMD from baseline to 12 month, and two sample t-test to examine the difference of BMD changes were used between two groups. BMD significantly decreased in both the CAB and GnRH groups, with no group wise differences. The proportion of osteopenia or osteoporosis was slightly increased after the 12-month post-ADT. Ten-year probability of hip fracture and major osteoporotic fracture was approximately 3% and 5%, respectively. In conclusion, a significant decrease of BMD by 12-month ADT was observed without any differences between the two groups, whereas ADT-related BMD loss did not induce detrimental effects on bone health in terms of increased bone fracture risk. This was the first prospective study on BMD changes as a predictor of fracture during ADT in an Asian population.

  16. Comparison of bone mineral loss by combined androgen block agonist versus GnRH in patients with prostate cancer: A 12 month-prospective observational study

    PubMed Central

    Kim, Sung Han; Joung, Jae Young; Kim, Sohee; Rha, Koon Ho; Kim, Hyeong Gon; Kwak, Cheol; Lee, Ji Youl; Jeon, Seong Soo; Hong, Sung Kyu; Jeong, Hyeon; Jo, Moon Ki; You, Dalsan; Jeong, In Gab; Hong, Jun Hyuk; Kim, Choung-Soo

    2017-01-01

    The multi-centre, prospective, observational study was designed to examine the efficacy of continuous combined androgen block (CAB) vs. GnRH agonist monotherapy in terms of bone mineral density (BMD) change during 12 months post-androgen deprivation therapy (ADT) in Asian prostate cancer patients. Multiple regression analysis and estimated the 10-year probability of major fractures among the patients with Fracture Risk Assessment Tool were conducted to investigate the underlying factors affecting BMD. Paired t-test to evaluate the change of BMD from baseline to 12 month, and two sample t-test to examine the difference of BMD changes were used between two groups. BMD significantly decreased in both the CAB and GnRH groups, with no group wise differences. The proportion of osteopenia or osteoporosis was slightly increased after the 12-month post-ADT. Ten-year probability of hip fracture and major osteoporotic fracture was approximately 3% and 5%, respectively. In conclusion, a significant decrease of BMD by 12-month ADT was observed without any differences between the two groups, whereas ADT-related BMD loss did not induce detrimental effects on bone health in terms of increased bone fracture risk. This was the first prospective study on BMD changes as a predictor of fracture during ADT in an Asian population. PMID:28262724

  17. Exercise training in obese older adults prevents increase in bone turnover and attenuates decrease in hip BMD induced by weight loss despite decline in bone-active hormones*

    PubMed Central

    Shah, Krupa; Armamento-Villareal, Reina; Parimi, Nehu; Chode, Suresh; Sinacore, David R.; Hilton, Tiffany N.; Napoli, Nicola; Qualls, Clifford; Villareal, Dennis T.

    2011-01-01

    Weight-loss therapy to improve health in obese older adults is controversial because it causes further bone loss. Therefore, it is recommended that weight-loss therapy should include an intervention to minimize bone loss such as exercise training (ET). The purpose of this study was to determine the independent and combined effects of weight loss and ET on bone metabolism in relation to bone mineral density (BMD) in obese older adults. One-hundred-seven older (age >65 yrs) obese (BMI ≥30 kg/m2) adults were randomly assigned to a control group, diet group, exercise group, and diet-exercise group for 1 year. Body weight decreased in the diet (−9.6%) and diet-exercise (−9.4%) groups, not in the exercise (−1%) and control (−0.2%) groups (between-group P<.001). However, despite comparable weight loss, bone loss at the total hip was relatively less in the diet-exercise group (−1.1%) than in the diet group (−2.6%), whereas BMD increased in the exercise group (1.5%) (between-group P<.001) Serum C-terminal telopeptide (CTX) and osteocalcin concentrations increased in the diet group (31% and 24%) while they decreased in the exercise group (−13% and −15%) (between-group P<.001). In contrast, similar to the control group, serum CTX and osteocalcin concentrations did not change in the diet-exercise group. Serum procollagen propeptide concentrations decreased in the exercise group (−15%) compared with the diet group (9%) (P=.04). Serum leptin and estradiol concentrations decreased in the diet (−25% and −15%) and diet-exercise (−38% and −13%) groups, not in the exercise and control groups (between-group P=.001). Multivariate analyses revealed that changes in lean body mass (β=.33), serum osteocalcin (β= −.24), and 1-RM strength (β=.23) were independent predictors of changes in hip BMD (all P<.05). In conclusion, the addition of ET to weight-loss therapy among obese older adults prevents weight-loss-induced increase in bone turnover and attenuates

  18. High-fat Diet Enhances and Plasminogen Activator Inhibitor-1 Deficiency Attenuates Bone Loss in Mice with Lewis Lung Carcinoma.

    PubMed

    Yan, Lin; Nielsen, Forrest H; Sundaram, Sneha; Cao, Jay

    2015-07-01

    This study determined the effects of a high-fat diet and plasminogen activator inhibitor-1 deficiency (Pai1(-/-)) on the bone structure in male C57BL/6 mice bearing Lewis lung carcinoma (LLC) in lungs. Significant reduction in bone volume fraction (BV/TV), trabecular number (Tb.N) and bone mineral density (BMD) in femurs and vertebrae were found in LLC-bearing mice compared to non-tumor-bearing mice. In LLC-bearing mice, the high-fat diet compared to the AIN93G control diet significantly reduced BV/TV, Tb.N and BMD in femurs and BV/TV in vertebrae. The high-fat diet significantly reduced BMD in vertebrae in wild-type mice but not in Pai1(-/-) mice. Compared to wild-type mice, PAI1 deficiency significantly increased BV/TV and Tb.N in femurs. The plasma concentration of osteocalcin was significantly lower and that of tartrate-resistant acid phosphatase 5b (TRAP5b) was significantly higher in LLC-bearing mice. The high-fat diet significantly reduced plasma osteocalcin and increased TRAP5b. Deficiency in PAI1 prevented the high-fat diet-induced increases in plasma TRAP5b. These findings demonstrate that a high-fat diet enhances, whereas PAI1 deficiency, attenuates metastasis-associated bone loss, indicating that a high-fat diet and PAI1 contribute to metastasis-associated bone deterioration. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  19. Whole-body bone segmentation from MRI for PET/MRI attenuation correction using shape-based averaging.

    PubMed

    Arabi, Hossein; Zaidi, Habib

    2016-11-01

    The authors evaluate the performance of shape-based averaging (SBA) technique for whole-body bone segmentation from MRI in the context of MRI-guided attenuation correction (MRAC) in hybrid PET/MRI. To enhance the performance of the SBA scheme, the authors propose to combine it with statistical atlas fusion techniques. Moreover, a fast and efficient shape comparison-based atlas selection scheme was developed and incorporated into the SBA method. Clinical studies consisting of PET/CT and MR images of 21 patients were used to assess the performance of the SBA method. In addition, the authors assessed the performance of simultaneous truth and performance level estimation (STAPLE) and the selective and iterative method for performance level estimation (SIMPLE) combined with SBA. In addition, a local shape comparison scheme (L-Shp) was proposed to improve the performance of SBA. The SIMPLE method was applied globally (G-SIMPLE) while STAPLE method was employed at both global (G-STAPLE) and local (L-STAPLE) levels. The evaluation was performed based on the accuracy of extracted whole-body bones, fragmentation, and computation time achieved by the different methods. The majority voting (MV) atlas fusion scheme was also evaluated as a conventional and commonly used method. MRI-guided attenuation maps were generated using the different segmentation methods. Thereafter, quantitative analysis of PET attenuation correction was performed using CT-based attenuation correction as reference. The SBA and MV methods resulted in considerable underestimation of bone identification (Dice ≈ 0.62) and high factious fragmentation error of contiguous structures. Applying global atlas selection or regularization (G-STAPLE and G-SIMPLE) to the SBA method enhanced bone segmentation accuracy up to a Dice = 0.66. The best results were achieved when applying the L-STAPLE method with a Dice of 0.76 and the L-Shp method with a Dice of 0.75. However, L-STAPLE required up to five-fold increased

  20. Involvement of angiotensin II type 2 receptor (AT2R) signaling in human pancreatic ductal adenocarcinoma (PDAC): a novel AT2R agonist effectively attenuates growth of PDAC grafts in mice

    PubMed Central

    Ishiguro, Susumu; Yoshimura, Kiyoshi; Tsunedomi, Ryouichi; Oka, Masaaki; Takao, Sonshin; Inui, Makoto; Kawabata, Atsushi; Wall, Terrahn; Magafa, Vassiliki; Cordopatis, Paul; Tzakos, Andreas G; Tamura, Masaaki

    2015-01-01

    We have recently discovered the potential involvement of angiotensin II type 2 receptor (AT2R) signaling in pancreatic cancer using AT2R deficient mice. To examine the involvement of AT2R expression in human PDAC, expressions of AT2R as well as the major angiotensin II receptor (type 1 receptor, AT1R) in human PDAC and adjacent normal tissue was evaluated by immunohistochemistry and real time PCR using surgically dissected human PDAC specimens. In immunohistochemical analysis, relatively strong AT1R expression was detected consistently in both normal pancreas and PDAC areas, whereas moderate AT2R expression was detected in 78.5% of PDAC specimens and 100% of normal area of the pancreas. AT1R, but not AT2R, mRNA levels were significantly higher in the PDAC area than in the normal pancreas. AT2R mRNA levels showed a negative correlation trend with overall survival. In cell cultures, treatment with a novel AT2R agonist significantly attenuated both murine and human PDAC cell growth with negligible cytotoxicity in normal epithelial cells. In a mouse study, administrations of the AT2R agonist in tumor surrounding connective tissue markedly attenuated growth of only AT2R expressing PAN02 murine PDAC grafts in syngeneic mice. The AT2R agonist treatment induced apoptosis primarily in tumor cells but not in stromal cells. Taken together, our findings offer clinical and preclinical evidence for the involvement of AT2R signaling in PDAC development and pinpoint that the novel AT2R agonist could serve as an effective therapeutic for PDAC treatment. PMID:25756513

  1. Administration of ON 01210.Na after exposure to ionizing radiation protects bone marrow cells by attenuating DNA damage response.

    PubMed

    Suman, Shubhankar; Maniar, Manoj; Fornace, Albert J; Datta, Kamal

    2012-01-20

    Ionizing radiation-induced hematopoietic injury could occur either due to accidental exposure or due to diagnostic and therapeutic interventions. Currently there is no approved drug to mitigate radiation toxicity in hematopoietic cells. This study investigates the potential of ON 01210.Na, a chlorobenzylsulfone derivative, in ameliorating radiation-induced hematopoietic toxicity when administered after exposure to radiation. We also investigate the molecular mechanisms underlying this activity. Male C3H/HeN mice (n = 5 mice per group; 6-8 weeks old) were exposed to a sub-lethal dose (5 Gy) of γ radiation using a ¹³⁷Cs source at a dose rate of 0.77 Gy/min. Two doses of ON 01210.Na (500 mg/kg body weight) were administered subcutaneously at 24 h and 36 h after radiation exposure. Mitigation of hematopoietic toxicity by ON 01210.Na was investigated by peripheral white blood cell (WBC) and platelet counts at 3, 7, 21, and 28 d after radiation exposure. Granulocyte macrophage colony forming unit (GM-CFU) assay was done using isolated bone marrow cells, and terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) was performed on bone marrow sections at 7 d post-exposure. The DNA damage response pathway involving ataxia telangiectasia mutated (ATM) and p53 was investigated by Western blot in bone marrow cells at 7 d post-exposure. Compared to the vehicle, ON 01210.Na treated mice showed accelerated recovery of peripheral WBC and platelet counts. Post-irradiation treatment of mice with ON 01210.Na also resulted in higher GM-CFU counts. The mitigation effects were accompanied by attenuation of ATM-p53-dependent DNA damage response in the bone marrow cells of ON 01210.Na treated mice. Both phospho-ATM and phospho-p53 were significantly lower in the bone marrow cells of ON 01210.Na treated than in vehicle treated mice. Furthermore, the Bcl2:Bax ratio was higher in the drug treated mice than the vehicle treated groups. ON 01210.Na treatment significantly

  2. Omentin-1 attenuates arterial calcification and bone loss in osteoprotegerin-deficient mice by inhibition of RANKL expression.

    PubMed

    Xie, Hui; Xie, Ping-Li; Wu, Xian-Ping; Chen, San-Mei; Zhou, Hou-De; Yuan, Ling-Qing; Sheng, Zhi-Feng; Tang, Si-Yuan; Luo, Xiang-Hang; Liao, Er-Yuan

    2011-11-01

    Omentin-1 (also known as intelectin-1) is a recently identified visceral adipose tissue-derived cytokine that is inversely related to obesity. Our previous study showed that omentin-1 inhibits osteoblastic differentiation of calcifying vascular smooth muscle cells (CVSMCs) in vitro. This study was undertaken to investigate the effects of omentin-1 on arterial calcification and bone metabolism in vivo. In vitro, omentin-1 stimulated production of osteoprotegerin (OPG) and inhibited production of receptor activator for nuclear factor κB ligand (RANKL) in both CVSMCs and osteoblasts. In vivo, adenovirus-mediated over-expression of omentin-1 attenuated arterial calcification and bone loss in OPG(-/-) mice. All these in vitro and in vivo actions were abrogated by blockade of the PI3K-Akt signalling pathway. Furthermore, omentin-1 reduced serum levels of RANKL, tartarate-resistant acid phosphatase-5b and osteocalcin, all of which are increased dramatically in OPG(-/-) mice. These data suggest that omentin-1 ameliorates arterial calcification and bone loss in vivo through the regulation of the RANK signalling pathway.

  3. Attenuated BMP1 Function Compromises Osteogenesis, Leading to Bone Fragility in Humans and Zebrafish

    PubMed Central

    Asharani, P.V.; Keupp, Katharina; Semler, Oliver; Wang, Wenshen; Li, Yun; Thiele, Holger; Yigit, Gökhan; Pohl, Esther; Becker, Jutta; Frommolt, Peter; Sonntag, Carmen; Altmüller, Janine; Zimmermann, Katharina; Greenspan, Daniel S.; Akarsu, Nurten A.; Netzer, Christian; Schönau, Eckhard; Wirth, Radu; Hammerschmidt, Matthias; Nürnberg, Peter; Wollnik, Bernd; Carney, Thomas J.

    2012-01-01

    Bone morphogenetic protein 1 (BMP1) is an astacin metalloprotease with important cellular functions and diverse substrates, including extracellular-matrix proteins and antagonists of some TGFβ superfamily members. Combining whole-exome sequencing and filtering for homozygous stretches of identified variants, we found a homozygous causative BMP1 mutation, c.34G>C, in a consanguineous family affected by increased bone mineral density and multiple recurrent fractures. The mutation is located within the BMP1 signal peptide and leads to impaired secretion and an alteration in posttranslational modification. We also characterize a zebrafish bone mutant harboring lesions in bmp1a, demonstrating conservation of BMP1 function in osteogenesis across species. Genetic, biochemical, and histological analyses of this mutant and a comparison to a second, similar locus reveal that Bmp1a is critically required for mature-collagen generation, downstream of osteoblast maturation, in bone. We thus define the molecular and cellular bases of BMP1-dependent osteogenesis and show the importance of this protein for bone formation and stability. PMID:22482805

  4. Attenuated BMP1 function compromises osteogenesis, leading to bone fragility in humans and zebrafish.

    PubMed

    Asharani, P V; Keupp, Katharina; Semler, Oliver; Wang, Wenshen; Li, Yun; Thiele, Holger; Yigit, Gökhan; Pohl, Esther; Becker, Jutta; Frommolt, Peter; Sonntag, Carmen; Altmüller, Janine; Zimmermann, Katharina; Greenspan, Daniel S; Akarsu, Nurten A; Netzer, Christian; Schönau, Eckhard; Wirth, Radu; Hammerschmidt, Matthias; Nürnberg, Peter; Wollnik, Bernd; Carney, Thomas J

    2012-04-06

    Bone morphogenetic protein 1 (BMP1) is an astacin metalloprotease with important cellular functions and diverse substrates, including extracellular-matrix proteins and antagonists of some TGFβ superfamily members. Combining whole-exome sequencing and filtering for homozygous stretches of identified variants, we found a homozygous causative BMP1 mutation, c.34G>C, in a consanguineous family affected by increased bone mineral density and multiple recurrent fractures. The mutation is located within the BMP1 signal peptide and leads to impaired secretion and an alteration in posttranslational modification. We also characterize a zebrafish bone mutant harboring lesions in bmp1a, demonstrating conservation of BMP1 function in osteogenesis across species. Genetic, biochemical, and histological analyses of this mutant and a comparison to a second, similar locus reveal that Bmp1a is critically required for mature-collagen generation, downstream of osteoblast maturation, in bone. We thus define the molecular and cellular bases of BMP1-dependent osteogenesis and show the importance of this protein for bone formation and stability.

  5. Glucosamines Attenuate Bone Loss Due to Menopause by Regulating Osteoclast Function in Ovariectomized Mice.

    PubMed

    Asai, Hironobu; Nakatani, Sachie; Kato, Takuya; Shimizu, Tatsuo; Mano, Hiroshi; Kobata, Kenji; Wada, Masahiro

    2016-01-01

    The effect of glucosamine (GlcN) and N-acetylglucosamine (GlcNAc) on bone metabolism in ovariectomized (OVX) mice was studied. After 12 weeks of feeding with 0.2% GlcN and 0.2% GlcNAc, the femoral bone mineral density in OVX mice was significantly increased compared with that in OVX mice fed the control diet. Histomorphometric analysis of the tibia indicated that the rates of osteogenesis and bone resorption were reduced due to the GlcN diet. The erosion depth of osteoclasts on the tibia in GlcN- and GlcNAc-fed OVX mice was significantly lower than that in the control OVX mice. The number of tartrate-resistant acid phosphatase-positive osteoclasts induced from bone marrow stem cells isolated from GlcN-fed OVX mice was significantly lower than that from control OVX mice. A loss of uterine weight and higher serum calcium concentration in the GlcN- and GlcNAc-fed OVX mice were observed. The results suggest that the intake of GlcN suppresses bone loss by inhibiting osteoclast differentiation and activity in a nonestrogenic manner.

  6. Attenuation of subchondral bone abnormal changes in osteoarthritis by inhibition of SDF-1 signaling.

    PubMed

    Chen, Y; Lin, S; Sun, Y; Guo, J; Lu, Y; Suen, C W; Zhang, J; Zha, Z; Ho, K W; Pan, X; Li, G

    2017-06-01

    Current conservative treatments for osteoarthritis (OA) are largely symptoms control therapies. Further understanding on the pathological mechanisms of OA is crucial for new pharmacological intervention. In this study, we investigated the role of Stromal cell-derived factor-1(SDF-1) in regulating subchondral bone changes during the progression of OA. Clinical samples of different stages of OA severity were analyzed by histology staining, micro-CT, enzyme-linked immunosorbent assay (ELISA) and western blotting, to compare SDF-1 level in subchondral bone. The effects of SDF-1 on human mesenchymal stem cells (MSCs) osteogenic differentiation were evaluated. In vivo assessment was performed in an anterior cruciate ligament transaction plus medial meniscus resection in the SD rats. The OA rats received continuous infusion of AMD3100 (SDF-1 receptor blocker) in osmotic mini-pump implanted subcutaneously for 6 weeks. These rats were then terminated and subjected to the same in vitro assessments as human OA samples. SDF-1 level was significantly elevated in the subchondral bone of human OA samples. In the cell studies, the results showed SDF-1 plays an important role in osteogenic differentiation of MSCs. In the OA animal studies, there were less cartilage damage in the AMD3100-treated group; microCT results showed that the subchondral bone formation was significantly reduced and so did the number of positive Nestin or Osterix cells in the subchondral bone region. Higher level of SDF-1 may induce the subchondral bone abnormal changes in OA and inhibition of SDF-1 signaling could be a potential therapeutic approach for OA. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  7. Correction of quantification errors in pelvic and spinal lesions caused by ignoring higher photon attenuation of bone in [18F]NaF PET/MR.

    PubMed

    Schramm, Georg; Maus, Jens; Hofheinz, Frank; Petr, Jan; Lougovski, Alexandr; Beuthien-Baumann, Bettina; Oehme, Liane; Platzek, Ivan; van den Hoff, Jörg

    2015-11-01

    MR-based attenuation correction (MRAC) in routine clinical whole-body positron emission tomography and magnetic resonance imaging (PET/MRI) is based on tissue type segmentation. Due to lack of MR signal in cortical bone and the varying signal of spongeous bone, standard whole-body segmentation-based MRAC ignores the higher attenuation of bone compared to the one of soft tissue (MRACnobone). The authors aim to quantify and reduce the bias introduced by MRACnobone in the standard uptake value (SUV) of spinal and pelvic lesions in 20 PET/MRI examinations with [18F]NaF. The authors reconstructed 20 PET/MR [18F]NaF patient data sets acquired with a Philips Ingenuity TF PET/MRI. The PET raw data were reconstructed with two different attenuation images. First, the authors used the vendor-provided MRAC algorithm that ignores the higher attenuation of bone to reconstruct PETnobone. Second, the authors used a threshold-based algorithm developed in their group to automatically segment bone structures in the [18F]NaF PET images. Subsequently, an attenuation coefficient of 0.11 cm(-1) was assigned to the segmented bone regions in the MRI-based attenuation image (MRACbone) which was used to reconstruct PETbone. The automatic bone segmentation algorithm was validated in six PET/CT [18F]NaF examinations. Relative SUVmean and SUVmax differences between PETbone and PETnobone of 8 pelvic and 41 spinal lesions, and of other regions such as lung, liver, and bladder, were calculated. By varying the assigned bone attenuation coefficient from 0.11 to 0.13 cm(-1), the authors investigated its influence on the reconstructed SUVs of the lesions. The comparison of [18F]NaF-based and CT-based bone segmentation in the six PET/CT patients showed a Dice similarity of 0.7 with a true positive rate of 0.72 and a false discovery rate of 0.33. The [18F]NaF-based bone segmentation worked well in the pelvis and spine. However, it showed artifacts in the skull and in the extremities. The analysis of the

  8. Induced Pluripotent Stem Cell Derived Mesenchymal Stem Cells for Attenuating Age-Related Bone Loss

    DTIC Science & Technology

    2013-09-01

    formation, are associated with gastrointestinal problems when taken orally and may cause osteonecrosis in cancer patients and bone pain in other...expression of osteoblastic phenotypic markers on iPS derived MSC cultured on nanotopographic biofilms . While we have not yet examined the effect

  9. Bone marrow fat has brown adipose tissue characteristics, which are attenuated with aging and diabetes.

    PubMed

    Krings, A; Rahman, S; Huang, S; Lu, Y; Czernik, P J; Lecka-Czernik, B

    2012-02-01

    Fat occupies a significant portion of bone cavity however its function is largely unknown. Marrow fat expands during aging and in conditions which affect energy metabolism, indicating that fat in bone is under similar regulatory mechanisms as other fat depots. On the other hand, its location may determine specific functions in the maintenance of the environment for bone remodeling and hematopoiesis. We have demonstrated that marrow fat has a distinctive phenotype, which resembles both, white and brown adipose tissue (WAT and BAT, respectively). Marrow adipocytes express gene markers of brown adipocytes at levels characteristic for the BAT, including transcription factor Prdm16, and regulators of thermogenesis such as deiodinase 2 (Dio2) and PGC1α. The levels of expression of BAT-specific gene markers are decreased in bone of 24 mo old C57BL/6 and in diabetic yellow agouti A(vy)/a mice implicating functional changes of marrow fat occurring with aging and diabetes. Administration of antidiabetic TZD rosiglitazone, which sensitizes cells to insulin and increases adipocyte metabolic functions, significantly increased both, BAT (UCP1, PGC1α, Dio2, β3AR, Prdm16, and FoxC2) and WAT (adiponectin and leptin) gene expression in marrow of normoglycemic C57BL/6 mice, but failed to increase the expression of BAT, but not WAT, gene markers in diabetic mice. In conclusion, the metabolic phenotype of marrow fat combines both BAT and WAT characteristics. Decrease in BAT-like characteristics with aging and diabetes may contribute to the negative changes in the marrow environment supporting bone remodeling and hematopoiesis.

  10. Plumbagin attenuates cancer cell growth and osteoclast formation in the bone microenvironment of mice

    PubMed Central

    Yan, Wei; Wang, Ting-yu; Fan, Qi-ming; Du, Lin; Xu, Jia-ke; Zhai, Zan-jing; Li, Hao-wei; Tang, Ting-ting

    2014-01-01

    Aim: To investigate the effects of plumbagin, a naphthoquinone derived from the medicinal plant Plumbago zeylanica, on human breast cancer cell growth and the cancer cell-induced osteolysis in the bone microenvironment of mice. Methods: Human breast cancer cell subline MDA-MB-231SA with the ability to spread and grow in the bone was tested. The cell proliferation was determined using the CCK-8 assay. Apoptosis was detected with Annexin V/PI double-labeled flow cytometry. Red fluorescent protein-labeled MDA-MB-231SArfp cells were injected into the right tibia of female BALB/c-nu/nu mice. Three days after the inoculation, the mice were injected with plumbagin (2, 4, or 6 mg/kg, ip) 5 times per week for 7 weeks. The growth of the tumor cells was monitored using an in vivo imaging system. After the mice were sacrificed, the hind limbs were removed for radiographic and histological analyses. Results: Plumbagin (2.5–20 μmol/L) concentration-dependently inhibited the cell viability and induced apoptosis of MDA-MB-231SA cells in vitro (the IC50 value of inhibition of cell viability was 14.7 μmol/L). Administration of plumbagin to breast cancer bearing mice delayed the tumor growth by 2–3 weeks and reduced the tumor volume by 44%–74%. The in vivo imaging study showed that plumbagin dose-dependently inhibited MDA-MB-231SArfp cell growth in bone microenvironment. Furthermore, X-ray images and micro-CT study demonstrated that plumbagin reduced bone erosion area and prevented a decrease in bone tissue volume. Histological studies showed that plumbagin dose-dependently inhibited the breast cancer cell growth, enhanced the cell apoptosis and reduced the number of TRAcP-positive osteoclasts. Conclusion: Plumbagin inhibits the cell growth and induces apoptosis in human breast cancer cells in mice bone microenvironment, leading to significant reduction in osteolytic lesions caused by the tumor cells. PMID:24384612

  11. Description and assessment of a registration-based approach to include bones for attenuation correction of whole-body PET/MRI.

    PubMed

    Marshall, Harry R; Patrick, John; Laidley, David; Prato, Frank S; Butler, John; Théberge, Jean; Thompson, R Terry; Stodilka, Robert Z

    2013-08-01

    Attenuation correction for whole-body PET/MRI is challenging. Most commercial systems compute the attenuation map from MRI using a four-tissue segmentation approach. Bones, the most electron-dense tissue, are neglected because they are difficult to segment. In this work, the authors build on this segmentation approach by adding bones using a registration technique and assessing its performance on human PET images. Twelve oncology patients were imaged with FDG PET/CT and MRI using a Turbo-FLASH pulse sequence. A database of 121 attenuation correction quality CT scans was also collected. Each patient MRI was compared to the CT database via weighted heuristic measures to find the "most similar" CT in terms of body geometry. The similar CT was aligned to the MRI with a deformable registration method. Two MRI-based attenuation maps were computed. One was a standard four-tissue segmentation (air, lung, fat, and lean tissue) using basic image processing techniques. The other was identical, except the bones from the aligned CT were added. The PET data were reconstructed with the patient's CT-based attenuation map (the silver standard) and both MRI-based attenuation maps. The relative errors of the MRI-based attenuation corrections were computed in 14 standardized volumes of interest, in lesions, and over whole tissues. The squared Pearson correlation coefficient was also calculated over whole tissues. Statistical testing was done with ANOVAs and paired t-tests. The MRI-based attenuation correction ignoring bone had relative errors ranging from -37% to -8% in volumes of interest containing bone. By including bone, the magnitude of the relative error was reduced in all cases (p<0.001), ranging from -3% to 4%. Further, the relative error in volumes of interest adjacent to bone was improved from a mean of -7.5% to 2% (p<0.001). In the other seven volumes of interest, including bone reduced the magnitude of relative error in three cases (p<0.001), had no effect in three cases

  12. Attenuation of bone morphogenetic protein signaling during amphibian limb development results in the generation of stage-specific defects

    PubMed Central

    Jones, Tamsin E M; Day, Robert C; Beck, Caroline W

    2013-01-01

    The vertebrate limb is one of the most intensively studied organs in the field of developmental biology. Limb development in tetrapod vertebrates is highly conserved and dependent on the interaction of several important molecular pathways. The bone morphogenetic protein (BMP) signaling cascade is one of these pathways and has been shown to be crucial for several aspects of limb development. Here, we have used a Xenopus laevis transgenic line, in which expression of the inhibitor Noggin is under the control of the heat-shock promoter hsp70 to examine the effects of attenuation of BMP signaling at different stages of limb development. Remarkably different phenotypes were produced at different stages, illustrating the varied roles of BMP in development of the limb. Very early limb buds appeared to be refractory to the effects of BMP attenuation, developing normally in most cases. Ectopic limbs were produced by overexpression of Noggin corresponding to a brief window of limb development at about stage 49/50, as recently described by Christen et al. (2012). Attenuation of BMP signaling in stage 51 or 52 tadpoles lead to a reduction in the number of digits formed, resulting in hypodactyly or ectrodactyly, as well as occasional defects in the more proximal tibia-fibula. Finally, inhibition at stage 54 (paddle stage) led to the formation of dramatically shortened digits resulting from loss of distal phalanges. Transcriptome analysis has revealed the possibility that more Noggin-sensitive members of the BMP family could be involved in limb development than previously suspected. Our analysis demonstrates the usefulness of heat-shock-driven gene expression as an effective method for inhibiting a developmental pathway at different times during limb development. PMID:23981117

  13. Intrathecal injection of selected peptide Myr-RC-13 attenuates bone cancer pain by inhibiting KIF17 and NR2B expression.

    PubMed

    Ni, Kun; Zhou, Yu; Sun, Yu-e; Liu, Yue; Gu, Xiao-ping; Ma, Zheng-liang

    2014-07-01

    Although bone cancer pain is a common intractable clinical symptom, its underlying mechanisms are still elusive. Accumulating evidence reveals that the N-methyl-D-aspartate (NMDA) receptor containing a 2B subunit (NR2B) in the spinal cord contributes to bone cancer pain. Our preliminary study demonstrated that intrathecal injection of fusion peptide Myr-RC-13 could disrupt spinal KIF17/mLin10 interaction, which is an essential component of KIF17-mediated NR2B transport. Here we report a means by infusion of the selected peptide Myr-RC-13 intrathecally to attenuate bone cancer pain. The results showed that inoculation of fibrosarcoma NCTC 2472 cells into the femur cavity of C3H/HeJ mice induced progressive bone cancer pain and resulted in up-regulation of KIF17 and NR2B in the spinal cord. In addition, repetitive spinal delivery of Myr-RC-13 relieved bone cancer-related mechanical allodynia and spontaneous pain behaviors, and down-regulated expression of spinal KIF17 and NR2B. Finally, our results demonstrated that selected peptide Myr-RC-13 was able to attenuate bone cancer pain via decreasing spinal KIF17 and NR2B expressions. Therefore, selected peptide Myr-RC-13 might be a potential analgesic strategy for bone cancer pain.

  14. Porous tantalum seeded with bone marrow mesenchymal stem cells attenuates steroid-associated osteonecrosis.

    PubMed

    Fu, W-M; Yang, L; Wang, B-J; Xu, J-K; Wang, J-L; Qin, L; Zhao, D-W

    2016-08-01

    Bone marrow mesenchymal stem cells (BMMSCs) have been widely applied in osteonecrosis. However, lack of biomechanical support limited application of BMMSCs. And porous tantalum (PTA) has been identified as a cell-friendly scaffold for bone regeneration. Herein, we aimed to investigate the efficacy of PTA seeded with BMMSCs in the treatment of osteonecrosis. After the production of PTA seeded with BMMSCs, MTT and GFP were performed to identify the proliferation and adhesion of BMMSCs respectively, which was further examined by scanning electron microscopy (SEM). And real-time PCR was also used to determine mRNA level of osteogenic markers, including Alp, OCN, OPN, Col I and Runx-2 in BMMSCs. Nineteen adult rabbits were applied for building steroid-associated osteonecrosis (SAON) models. Bone formation rate (BFR) and mineral apposition rate (MAR) were determined. And Goldner Trichrome Staining was used in these SAON models, which further confirmed the efficacy of PTA seeded with BMMSCs in SAON. PTA seeded with BMMSCs showed excellent biocompatibility. Additionally, SEM assay showed that BMMSCs adhered tightly and spread fully in the pores of PTA. Next, the expression of ALP and OPN mRNA in BMMSCs were significantly (p < 0.05) higher in the PTA-treated group compared to those in the PTA-untreated group. Furthermore, compared to those treated by only PTA, the dynamic bone formation in rabbits treated by PTA seeded with BMMSCs was significantly increased (p < 0.001) at both week 3rd and week 6th. The product, PTA seeded with BMMSCs, was successfully produced, and was determined as high efficacy for treatment of steroid-associated osteonecrosis. PTA seeded with BMMSCs may afford a promising option for treating osteonecrosis.

  15. Bone Marrow-Derived Tenascin-C Attenuates Cardiac Hypertrophy by Controlling Inflammation.

    PubMed

    Song, Lei; Wang, Lai; Li, Fuqiang; Yukht, Ada; Qin, Minghui; Ruther, Haley; Yang, Mingjie; Chaux, Aurelio; Shah, Prediman K; Sharifi, Behrooz G

    2017-09-26

    Tenascin-C (TNC) is a highly conserved matricellular protein with a distinct expression pattern during development and disease. Remodeling of the left ventricle (LV) in response to pressure overload leads to the re-expression of the fetal gene program. The aim of this study was to investigate the function of TNC in cardiac hypertrophy in response to pressure overload. Pressure overload was induced in TNC knockout and wild-type mice by constricting their abdominal aorta or by infusion of angiotensin II. Echocardiography, immunostaining, flow cytometry, quantitative real-time polymerase chain reaction, and reciprocal bone marrow transplantation were used to evaluate the effect of TNC deficiency. Echocardiographic analysis of pressure overloaded hearts revealed that all LV parameters (LV end-diastolic and -systolic dimensions, ejection fraction, and fractional shortening) deteriorated in TNC-deficient mice compared with their wild-type counterparts. Cardiomyocyte size and collagen accumulation were significantly greater in the absence of TNC. Mechanistically, TNC deficiency promoted rapid accumulation of the CCR2(+)/Ly6C(hi) monocyte/macrophage subset into the myocardium in response to pressure overload. Further, echocardiographic and immunohistochemical analyses of recipient hearts showed that expression of TNC in the bone marrow, but not the myocardium, protected the myocardium against excessive remodeling of the pressure-overloaded heart. TNC deficiency further impaired cardiac function in response to pressure overload and exacerbated fibrosis by enhancing inflammation. In addition, expression of TNC in the bone marrow, but not the myocardium, protected the myocardium against excessive remodeling in response to mild pressure overload. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  16. High-Dose Vitamin D and Calcium Attenuates Bone Loss with Antiretroviral Therapy Initiation

    PubMed Central

    Overton, Edgar Turner; Chan, Ellen S.; Brown, Todd T.; Tebas, Pablo; McComsey, Grace A.; Melbourne, Kathleen M.; Napoli, Andrew; Hardin, William Royce; Ribaudo, Heather J.; Yin, Michael T.

    2015-01-01

    Background Antiretroviral therapy (ART) initiation for HIV-1 infection is associated with 2-6% loss in bone mineral density (BMD). Objective To evaluate vitamin D3 (4000 IU daily) plus calcium (1000 mg calcium carbonate daily) supplementation on bone loss associated with ART initiation. Design 48-week prospective, randomized, double-blind, placebo-controlled study. Setting Thirty nine AIDS Clinical Trials Network research units. Participants ART-naïve HIV-infected adults. Measurements BMD by dual-energy X-ray absorptiometry (DXA); 25-hydroxy vitamin D (25(OH)D) levels, parathyroid hormone (PTH), phosphate metabolism, markers of bone turnover and systemic inflammation. Results 165 eligible subjects were randomized (79 Vitamin D/calcium (VitD/Cal); 86 placebo); 142 subjects with evaluable DXA data were included in the primary analysis. The study arms were well-balanced at baseline: median age 33 years; 90% male; 33% non-Hispanic black; median CD4 count 341 cells/mm3; and median 25(OH)D 23 ng/mL (57 nmol/L). At 48 weeks, subjects receiving placebo had greater decline in total hip BMD than VitD/Cal: −3.19% median change (1st-3rd quartile (Q1, Q3) −5.12%, −1.02%) vs. (−1.46% −3.16%,−0.40%). respectively (p=0.001). Lumbar spine BMD loss for the two groups was similar: −2.91% (−4.84%, −1.06%) vs. −1.41% (−3.78%, 0.00%), (p=0.085). At week 48, 90% of participants achieved HIV-1 RNA <50 copies/mL. Levels of 25(OH)D3 increased in the VitD/Cal but not the placebo group: median change of 24.5 (14.6, 37.8) vs. 0.7 (−5.3, 4.3) ng/mL, respectively (p<0.001). Additionally, increases in markers of bone turnover were blunted in the VitD/Cal group. Limitations No international sites were included; only 48 weeks of follow up Conclusion Vitamin D/calcium supplementation mitigates the loss of BMD seen with initiation of efavirenz/emtricitabine/tenofovir, particularly at the total hip, which is the site of greatest concern for fragility fracture. Primary Funding

  17. Effects of adenosine A(3) receptor agonist on bone marrow granulocytic system in 5-fluorouracil-treated mice.

    PubMed

    Hofer, Michal; Pospísil, Milan; Vacek, Antonín; Holá, Jirina; Znojil, Vladimír; Weiterová, Lenka; Streitová, Denisa

    2006-05-24

    The purpose of the experiments reported was to investigate effects of N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA), a selective adenosine A(3) receptor agonist, on the granulocytic system in femoral marrow of mice depleted by the cytotoxic drug 5-fluorouracil. In the phase of the highest cell depletion IB-MECA was injected i.p. at single doses of 200 nmol/kg given either once or twice daily in 2- and 4-day regimens starting on day 1 after 5-fluorouracil administration; the effects were evaluated on days 3 and 5, respectively. The general effect of IB-MECA in all these experiments was an enhancement of the counts of morphologically recognizable proliferative granulocytic cells, interpreted as evidence of the differentiation of committed progenitor cells. A more expressive effect was observed after IB-MECA injected twice daily. It was found that the induction of the strong differentiation pressures by IB-MECA given twice daily shortly after 5-fluorouracil treatment can be counterproductive due to the preponderance of differentiaton processes over the proliferation control. In additional experiments, it has been shown that the use of the 2-day administration of IB-MECA given twice daily in the recovery phase, i.e., on days 5 and 6 after 5-fluorouracil administration, does not induce stimulatory effects. Thus, the dosing and timing of IB-MECA treatment determines its effectivity in stimulating granulopoiesis under conditions of myelosuppression.

  18. A Randomised Comparison Evaluating Changes in Bone Mineral Density in Advanced Prostate Cancer: Luteinising Hormone-releasing Hormone Agonists Versus Transdermal Oestradiol

    PubMed Central

    Langley, Ruth E.; Kynaston, Howard G.; Alhasso, Abdulla A.; Duong, Trinh; Paez, Edgar M.; Jovic, Gordana; Scrase, Christopher D.; Robertson, Andrew; Cafferty, Fay; Welland, Andrew; Carpenter, Robin; Honeyfield, Lesley; Abel, Richard L.; Stone, Michael; Parmar, Mahesh K.B.; Abel, Paul D.

    2016-01-01

    Background Luteinising hormone-releasing hormone agonists (LHRHa), used as androgen deprivation therapy (ADT) in prostate cancer (PCa) management, reduce serum oestradiol as well as testosterone, causing bone mineral density (BMD) loss. Transdermal oestradiol is a potential alternative to LHRHa. Objective To compare BMD change in men receiving either LHRHa or oestradiol patches (OP). Design, setting, and participants Men with locally advanced or metastatic PCa participating in the randomised UK Prostate Adenocarcinoma TransCutaneous Hormones (PATCH) trial (allocation ratio of 1:2 for LHRHa:OP, 2006–2011; 1:1, thereafter) were recruited into a BMD study (2006–2012). Dual-energy x-ray absorptiometry scans were performed at baseline, 1 yr, and 2 yr. Interventions LHRHa as per local practice, OP (FemSeven 100 μg/24 h patches). Outcome measurements and statistical analysis The primary outcome was 1-yr change in lumbar spine (LS) BMD from baseline compared between randomised arms using analysis of covariance. Results and limitations A total of 74 eligible men (LHRHa 28, OP 46) participated from seven centres. Baseline clinical characteristics and 3-mo castration rates (testosterone ≤1.7 nmol/l, LHRHa 96% [26 of 27], OP 96% [43 of 45]) were similar between arms. Mean 1-yr change in LS BMD was −0.021 g/cm3 for patients randomised to the LHRHa arm (mean percentage change −1.4%) and +0.069 g/cm3 for the OP arm (+6.0%; p < 0.001). Similar patterns were seen in hip and total body measurements. The largest difference between arms was at 2 yr for those remaining on allocated treatment only: LS BMD mean percentage change LHRHa −3.0% and OP +7.9% (p < 0.001). Conclusions Transdermal oestradiol as a single agent produces castration levels of testosterone while mitigating BMD loss. These early data provide further supporting evidence for the ongoing phase 3 trial. Patient summary This study found that prostate cancer patients treated with transdermal oestradiol

  19. Bone marrow mesenchymal stem cells attenuate silica-induced pulmonary fibrosis via paracrine mechanisms.

    PubMed

    Li, Xiaoli; Wang, Yan; An, Guoliang; Liang, Di; Zhu, Zhonghui; Lian, Ximeng; Niu, Piye; Guo, Caixia; Tian, Lin

    2017-03-15

    The purpose of this study was to investigate the anti-fibrotic effect and possible mechanism of bone marrow mesenchymal stem cells (BMSCs) in silica-induced lung injury and fibrosis in vivo and in vitro. In vivo, rats were exposed to 50mg/ml silica intratracheally. The rats were sacrificed on day 15 or day 30 after intravenous injection of BMSCs. Histopathological examination demonstrated that BMSCs decreased the blue areas of collagen fibers and the number of nodules. Alveolar epithelium was damaged by silica, but it was restored by BMSCs. In vitro, BMSCs co-cultured with RLE-6TN cells in 6-Transwell plates were evaluated to determine the possible mechanism. The results demonstrated that BMSCs downregulated the expression of collagen I and III. BMSCs reversed morphological abnormalities and reduced the proliferation of RLE-6TN cells. These data showed that BMSCs did not give rise to alveolar epithelial cells directly, while the levels of hepatocyte growth factor, keratinocyte growth factor and bone morphogenetic protein -7 increased and expression of tumor necrosis factor-α and transforming growth factor-β1 decreased in the 6TN+Silica+BMSCs group compared with the 6TN+Silica group. Our results revealed that BMSCs exerted anti-fibrotic effects on silica-induced pulmonary fibrosis, which might be associated with paracrine mechanisms rather than differentiation.

  20. Therapeutic potential of the dual peroxisome proliferator activated receptor (PPAR)α/γ agonist aleglitazar in attenuating TNF-α-mediated inflammation and insulin resistance in human adipocytes.

    PubMed

    Massaro, Marika; Scoditti, Egeria; Pellegrino, Mariangela; Carluccio, Maria Annunziata; Calabriso, Nadia; Wabitsch, Martin; Storelli, Carlo; Wright, Matthew; De Caterina, Raffaele

    2016-05-01

    Adipose tissue inflammation is a mechanistic link between obesity and its related sequelae, including insulin resistance and type 2 diabetes. Dual ligands of peroxisome proliferator activated receptor (PPAR)α and γ, combining in a single molecule the metabolic and inflammatory-regulatory properties of α and γ agonists, have been proposed as a promising therapeutic strategy to antagonize adipose tissue inflammation. Here we investigated the effects of the dual PPARα/γ agonist aleglitazar on human adipocytes challenged with inflammatory stimuli. Human Simpson-Golabi-Behmel syndrome (SGBS) adipocytes were treated with aleglitazar or - for comparison - the selective agonists for PPARα or γ fenofibrate or rosiglitazone, respectively, for 24h before stimulation with TNF-α. Aleglitazar, at concentrations as low as 10nmol/L, providing the half-maximal transcriptional activation of both PPARα and PPARγ, reduced the stimulated expression of several pro-inflammatory mediators including interleukin (IL)-6, the chemokine CXC-L10, and monocyte chemoattractant protein (MCP)-1. Correspondingly, media from adipocytes treated with aleglitazar reduced monocyte migration, consistent with suppression of MCP-1 secretion. Under the same conditions, aleglitazar also reversed the TNF-α-mediated suppression of insulin-stimulated ser473 Akt phosphorylation and decreased the TNF-α-induced ser312 IRS1 phosphorylation, two major switches in insulin-mediated metabolic activities, restoring glucose uptake in insulin-resistant adipocytes. Such effects were similar to those obtainable with a combination of single PPARα and γ agonists. In conclusion, aleglitazar reduces inflammatory activation and dysfunction in insulin signaling in activated adipocytes, properties that may benefit diabetic and obese patients. The effect of aleglitazar was consistent with dual PPARα and γ agonism, but with no evidence of synergism. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Spinal and peripheral analgesic effects of the CB2 cannabinoid receptor agonist AM1241 in two models of bone cancer-induced pain.

    PubMed

    Curto-Reyes, V; Llames, S; Hidalgo, A; Menéndez, L; Baamonde, A

    2010-06-01

    The activation of CB(2) receptors induces analgesia in experimental models of chronic pain. The present experiments were designed to study whether the activation of peripheral or spinal CB(2) receptors relieves thermal hyperalgesia and mechanical allodynia in two models of bone cancer pain. NCTC 2472 osteosarcoma or B16-F10 melanoma cells were intratibially inoculated to C3H/He and C57BL/6 mice. Thermal hyperalgesia was assessed by the unilateral hot plate test and mechanical allodynia by the von Frey test. AM1241 (CB(2) receptor agonist), AM251 (CB(1) receptor antagonist), SR144528 (CB(2) receptor antagonist) and naloxone were used. CB(2) receptor expression was measured by Western blot. AM1241 (0.3-10 mg.kg(-1)) abolished thermal hyperalgesia and mechanical allodynia in both tumour models. The antihyperalgesic effect was antagonized by subcutaneous, intrathecal or peri-tumour administration of SR144528. In contrast, the antiallodynic effect was inhibited by systemic or intrathecal, but not peri-tumour, injection of SR144528. The effects of AM1241 were unchanged by AM251 but were prevented by naloxone. No change in CB(2) receptor expression was found in spinal cord or dorsal root ganglia. Spinal CB(2) receptors are involved in the antiallodynic effect induced by AM1241 in two neoplastic models while peripheral and spinal receptors participate in the antihyperalgesic effects. Both effects were mediated by endogenous opiates. The use of drugs that activate CB(2) receptors could be a useful strategy to counteract bone cancer-induced pain symptoms.

  2. Spinal and peripheral analgesic effects of the CB2 cannabinoid receptor agonist AM1241 in two models of bone cancer-induced pain

    PubMed Central

    Curto-Reyes, V; Llames, S; Hidalgo, A; Menéndez, L; Baamonde, A

    2010-01-01

    Background and purpose: The activation of CB2 receptors induces analgesia in experimental models of chronic pain. The present experiments were designed to study whether the activation of peripheral or spinal CB2 receptors relieves thermal hyperalgesia and mechanical allodynia in two models of bone cancer pain. Experimental approach: NCTC 2472 osteosarcoma or B16-F10 melanoma cells were intratibially inoculated to C3H/He and C57BL/6 mice. Thermal hyperalgesia was assessed by the unilateral hot plate test and mechanical allodynia by the von Frey test. AM1241 (CB2 receptor agonist), AM251 (CB1 receptor antagonist), SR144528 (CB2 receptor antagonist) and naloxone were used. CB2 receptor expression was measured by Western blot. Key results: AM1241 (0.3–10 mg·kg−1) abolished thermal hyperalgesia and mechanical allodynia in both tumour models. The antihyperalgesic effect was antagonized by subcutaneous, intrathecal or peri-tumour administration of SR144528. In contrast, the antiallodynic effect was inhibited by systemic or intrathecal, but not peri-tumour, injection of SR144528. The effects of AM1241 were unchanged by AM251 but were prevented by naloxone. No change in CB2 receptor expression was found in spinal cord or dorsal root ganglia. Conclusions and implications: Spinal CB2 receptors are involved in the antiallodynic effect induced by AM1241 in two neoplastic models while peripheral and spinal receptors participate in the antihyperalgesic effects. Both effects were mediated by endogenous opiates. The use of drugs that activate CB2 receptors could be a useful strategy to counteract bone cancer-induced pain symptoms. PMID:20233215

  3. Minocycline attenuates bone cancer pain in rats by inhibiting NF-κB in spinal astrocytes

    PubMed Central

    Song, Zhen-peng; Xiong, Bing-rui; Guan, Xue-hai; Cao, Fei; Manyande, Anne; Zhou, Ya-qun; Zheng, Hua; Tian, Yu-ke

    2016-01-01

    Aim: To investigate the mechanisms underlying the anti-nociceptive effect of minocycline on bone cancer pain (BCP) in rats. Methods: A rat model of BCP was established by inoculating Walker 256 mammary carcinoma cells into tibial medullary canal. Two weeks later, the rats were injected with minocycline (50, 100 μg, intrathecally; or 40, 80 mg/kg, ip) twice daily for 3 consecutive days. Mechanical paw withdrawal threshold (PWT) was used to assess pain behavior. After the rats were euthanized, spinal cords were harvested for immunoblotting analyses. The effects of minocycline on NF-κB activation were also examined in primary rat astrocytes stimulated with IL-1β in vitro. Results: BCP rats had marked bone destruction, and showed mechanical tactile allodynia on d 7 and d 14 after the operation. Intrathecal injection of minocycline (100 μg) or intraperitoneal injection of minocycline (80 mg/kg) reversed BCP-induced mechanical tactile allodynia. Furthermore, intraperitoneal injection of minocycline (80 mg/kg) reversed BCP-induced upregulation of GFAP (astrocyte marker) and PSD95 in spinal cord. Moreover, intraperitoneal injection of minocycline (80 mg/kg) reversed BCP-induced upregulation of NF-κB, p-IKKα and IκBα in spinal cord. In IL-1β-stimulated primary rat astrocytes, pretreatment with minocycline (75, 100 μmol/L) significantly inhibited the translocation of NF-κB to nucleus. Conclusion: Minocycline effectively alleviates BCP by inhibiting the NF-κB signaling pathway in spinal astrocytes. PMID:27157092

  4. Exercise training in obese older adults prevents increase in bone turnover and attenuates decrease in hip bone mineral density induced by weight loss despite decline in bone-active hormones.

    PubMed

    Shah, Krupa; Armamento-Villareal, Reina; Parimi, Nehu; Chode, Suresh; Sinacore, David R; Hilton, Tiffany N; Napoli, Nicola; Qualls, Clifford; Villareal, Dennis T

    2011-12-01

    0.05). In conclusion, the addition of ET to weight loss therapy among obese older adults prevents weight loss-induced increase in bone turnover and attenuates weight loss-induced reduction in hip BMD despite weight loss-induced decrease in bone-active hormones. Copyright © 2011 American Society for Bone and Mineral Research.

  5. FGFR1 signaling in hypertrophic chondrocytes is attenuated by the Ras-GAP neurofibromin during endochondral bone formation

    PubMed Central

    Karolak, Matthew R.; Yang, Xiangli; Elefteriou, Florent

    2015-01-01

    Aberrant fibroblast growth factor receptor 3 (FGFR3) signaling disrupts chondrocyte proliferation and growth plate size and architecture, leading to various chondrodysplasias or bone overgrowth. These observations suggest that the duration, intensity and cellular context of FGFR signaling during growth plate chondrocyte maturation require tight, regulated control for proper bone elongation. However, the machinery fine-tuning FGFR signaling in chondrocytes is incompletely defined. We report here that neurofibromin, a Ras-GAP encoded by Nf1, has an overlapping expression pattern with FGFR1 and FGFR3 in prehypertrophic chondrocytes, and with FGFR1 in hypertrophic chondrocytes during endochondral ossification. Based on previous evidence that neurofibromin inhibits Ras-ERK signaling in chondrocytes and phenotypic analogies between mice with constitutive FGFR1 activation and Nf1 deficiency in Col2a1-positive chondrocytes, we asked whether neurofibromin is required to control FGFR1-Ras-ERK signaling in maturing chondrocytes in vivo. Genetic Nf1 ablation in Fgfr1-deficient chondrocytes reactivated Ras-ERK1/2 signaling in hypertrophic chondrocytes and reversed the expansion of the hypertrophic zone observed in mice lacking Fgfr1 in Col2a1-positive chondrocytes. Histomorphometric and gene expression analyses suggested that neurofibromin, by inhibiting Rankl expression, attenuates pro-osteoclastogenic FGFR1 signaling in hypertrophic chondrocytes. We also provide evidence suggesting that neurofibromin in prehypertrophic chondrocytes, downstream of FGFRs and via an indirect mechanism, is required for normal extension and organization of proliferative columns. Collectively, this study indicates that FGFR signaling provides an important input into the Ras-Raf-MEK-ERK1/2 signaling axis in chondrocytes, and that this input is differentially regulated during chondrocyte maturation by a complex intracellular machinery, of which neurofibromin is a critical component. PMID:25616962

  6. Bone marrow-derived mesenchymal stem cells attenuate phosgene-induced acute lung injury in rats.

    PubMed

    Chen, Junfeng; Shao, Yiru; Xu, Guoxiong; Lim, ChitChoon; Li, Jun; Xu, Daojian; Shen, Jie

    2015-01-01

    Accidental phosgene exposure could result in acute lung injury (ALI), effective therapy is needed for the patients with phosgene-induced ALI. As a type of cells with therapeutic potential, mesenchymal stem cells (MSCs) have been showed its efficacy in multiple diseases. Here, we assessed the therapeutic potential of MSCs in phosgene-induced ALI and explored the related mechanisms. After isolation and characterization of rat bone marrow MSCs (BMMSCs), we transplanted BMMSCs into the rats exposed to phosgene and observed significant improvement on the lung wet-to-dry ratio and partial oxygen pressure (PaO2) at 6, 24, 48 h after phosgene exposure. Histological analyses revealed reduced sign of pathological changes in the lungs. Reduced level of pro-inflammatory tumor necrosis factor α and increased level of anti-inflammatory factor interleukin-10 were found in both bronchoalveolar lavage and plasma. Significant increased expression of epithelial cell marker AQP5 and SP-C was also found in the lung tissue. In conclusion, treatment with MSC markedly decreases the severity of phosgene-induced ALI in rats, and these protection effects were closely related to the pulmonary air blood barrier repairment and inflammatory reaction regulation.

  7. Bone Marrow Stem/Progenitor Cells Attenuate the Inflammatory Milieu Following Substitution Urethroplasty

    PubMed Central

    Liu, Joceline S.; Bury, Matthew I.; Fuller, Natalie J.; Sturm, Renea M.; Ahmad, Nida; Sharma, Arun K.

    2016-01-01

    Substitution urethroplasty for the treatment of male stricture disease is often accompanied by subsequent tissue fibrosis and secondary stricture formation. Patients with pre-existing morbidities are often at increased risk of urethral stricture recurrence brought upon in-part by delayed vascularization accompanied by overactive inflammatory responses following surgery. Within the context of this study, we demonstrate the functional utility of a cell/scaffold composite graft comprised of human bone marrow-derived mesenchymal stem cells (MSC) combined with CD34+ hematopoietic stem/progenitor cells (HSPC) to modulate inflammation and wound healing in a rodent model of substitution urethroplasty. Composite grafts demonstrated potent anti-inflammatory effects with regards to tissue macrophage and neutrophil density following urethral tissue analyses. This was accompanied by a significant reduction in pro-inflammatory cytokines TNFα and IL-1β and further resulted in an earlier transition to tissue remodeling and maturation with a shift in collagen type III to I. Grafted animals demonstrated a progressive maturation and increase in vessel size compared to control animals. Overall, MSC/CD34+ HSPC composite grafts reduce inflammation, enhance an earlier transition to wound remodeling and maturation concurrently increasing neovascularization in the periurethral tissue. We demonstrate the feasibility and efficacy of a stem cell-seeded synthetic graft in a rodent substitution urethroplasty model. PMID:27762304

  8. Infusion of Bone Marrow Mesenchymal Stem Cells Attenuates Experimental Severe Acute Pancreatitis in Rats

    PubMed Central

    Huang, Dandan; Gao, Jun; Gong, Yanfang; Wu, Hongyu; Xu, Aifang

    2016-01-01

    Background & Aims. Severe acute pancreatitis (SAP) remains a high-mortality disease. Bone marrow (BM) mesenchymal stem cells (MSCs) have been demonstrated to have plasticity of transdifferentiation and to have immunomodulatory functions. In the present study, we assessed the roles of MSCs in SAP and the therapeutic effects of MSC on SAP after transplantation. Methods. A pancreatitis rat model was induced by the injection of taurocholic acid (TCA) into the pancreatic duct. After isolation and characterization of MSC from BM, MSC transplantation was conducted 24 hrs after SAP induction by tail vein injection. The survival rate was observed and MSCs were traced after transplantation. The expression of TNF-α and IL-1β mRNA in the transplantation group was also analyzed. Results. The survival rate of the transplantation group was significantly higher compared to the control group (p < 0.05). Infused MSCs were detected in the pancreas and BM 3 days after transplantation. The expression of TNF-α and IL-1β mRNA in the transplantation group was significantly lower than in the control group in both the pancreas and the lungs (p < 0.05). Conclusions. MSC transplantation could improve the prognosis of SAP rats. Engrafted MSCs have the capacity of homing, migration, and planting during the treatment of SAP. PMID:27721836

  9. Intrathecal injection of glutamate receptor antagonists/agonist selectively attenuated rat pain-related behaviors induced by the venom of scorpion Buthus martensi Karsch.

    PubMed

    Liu, Tong; Pang, Xue-Yan; Bai, Zhan-Tao; Chai, Zhi-Fang; Jiang, Feng; Ji, Yong-Hua

    2007-12-15

    The present study investigated the involvement of spinal glutamate receptors in the induction and maintenance of the pain-related behaviors induced by the venom of scorpion Buthus martensi Karsch (BmK). (5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5-10-imine hydrogen maleate (MK-801; 40nmol; a non-competitive NMDA receptor antagonist), 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 40nmol; a non-NMDA receptor antagonist), dl-amino-3-phosphonopropionic acid (dl-AP3; 100nmol; a group I metabotropic glutamate receptor antagonist) and 4-aminopyrrolidine-2,4-dicarboxylate (APDC; 100nmol; a group II metabotropic glutamate receptor agonist) were employed. On intrathecal injection of glutamate receptor antagonists/agonist before BmK venom administration by 10min, BmK venom-induced spontaneous nociceptive responses could be suppressed by all tested agents. Primary thermal hyperalgesia could be inhibited by MK-801 and dl-AP3, while bilateral mechanical hyperalgesia could be inhibited by CNQX and dl-AP3 and contralateral mechanical hyperalgesia could be inhibited by APDC. On intrathecal injection of glutamate receptor antagonists/agonist after BmK venom injection by 4.5h, primary thermal hyperalgesia could be partially reversed by all tested agents, while bilateral mechanical hyperalgesia could only be inhibited by APDC. The results suggest that the role of spinal glutamate receptors may be different on the various manifestations of BmK venom-induced pain-related behaviors.

  10. Green Tea Modulates Cytokine Expression in the Periodontium and Attenuates Alveolar Bone Resorption in Type 1 Diabetic Rats.

    PubMed

    Gennaro, Gabriela; Claudino, Marcela; Cestari, Tania Mary; Ceolin, Daniele; Germino, Patrícia; Garlet, Gustavo Pompermaier; de Assis, Gerson Francisco

    2015-01-01

    Diabetes mellitus comprises a heterogeneous group of disorders with the main feature of hyperglycemia. Chronic hyperglycemia increases the severity of periodontal disease via an exacerbated inflammatory response, activated by advanced glycation end products and their receptor, RAGE. Therefore, anti-inflammatory agents represent potential inhibitors of this pathological interaction. In particular, green tea has been shown to possess anti-inflammatory properties mediated by its polyphenol content. This study investigated the mechanisms by which green tea attenuates the spontaneous onset of diabetes-induced periodontitis. Diabetes was induced in rats via a single intraperitoneal injection of streptozotocin (STZ). Diabetic and control animals were divided into water-treated and green tea-treated subgroups and were analyzed at 15, 30, 60 and 90 days after diabetes induction. Immunohistochemistry was performed to quantitatively evaluate tumor necrosis factor-α (TNF-α), receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG), interleukin-10 (IL-10) and runt-related transcription factor 2 (RUNX-2) expression in serial sections of each hemimaxilla. Morphometric measurements of the distance from the cementum-enamel junction (CEJ) of the superior distal root of the first molar to the alveolar bone crest (ABC) were performed to assess bone loss. Diabetes resulted in significant bone loss and alterations in the number of cells that stained positive for inflammatory mediators. In the diabetic rats treated with green tea, we observed a decreased number of cells expressing RANKL and TNF-α compared with that observed in the diabetic rats treated with water. Additionally, green tea increased the numbers of cells that stained positive for OPG, RUNX-2 and IL-10 in the diabetic rats. Green tea intake reduces expression of the pro-inflammatory cytokine TNF-α and the osteoclastogenic mediator RANKL to normal levels while increasing expression of the anti

  11. Green Tea Modulates Cytokine Expression in the Periodontium and Attenuates Alveolar Bone Resorption in Type 1 Diabetic Rats

    PubMed Central

    Gennaro, Gabriela; Claudino, Marcela; Cestari, Tania Mary; Ceolin, Daniele; Germino, Patrícia; Garlet, Gustavo Pompermaier; de Assis, Gerson Francisco

    2015-01-01

    Diabetes mellitus comprises a heterogeneous group of disorders with the main feature of hyperglycemia. Chronic hyperglycemia increases the severity of periodontal disease via an exacerbated inflammatory response, activated by advanced glycation end products and their receptor, RAGE. Therefore, anti-inflammatory agents represent potential inhibitors of this pathological interaction. In particular, green tea has been shown to possess anti-inflammatory properties mediated by its polyphenol content. Objectives: This study investigated the mechanisms by which green tea attenuates the spontaneous onset of diabetes-induced periodontitis. Methods: Diabetes was induced in rats via a single intraperitoneal injection of streptozotocin (STZ). Diabetic and control animals were divided into water-treated and green tea-treated subgroups and were analyzed at 15, 30, 60 and 90 days after diabetes induction. Immunohistochemistry was performed to quantitatively evaluate tumor necrosis factor-α (TNF-α), receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG), interleukin-10 (IL-10) and runt-related transcription factor 2 (RUNX-2) expression in serial sections of each hemimaxilla. Morphometric measurements of the distance from the cementum-enamel junction (CEJ) of the superior distal root of the first molar to the alveolar bone crest (ABC) were performed to assess bone loss. Results: Diabetes resulted in significant bone loss and alterations in the number of cells that stained positive for inflammatory mediators. In the diabetic rats treated with green tea, we observed a decreased number of cells expressing RANKL and TNF-α compared with that observed in the diabetic rats treated with water. Additionally, green tea increased the numbers of cells that stained positive for OPG, RUNX-2 and IL-10 in the diabetic rats. Conclusion: Green tea intake reduces expression of the pro-inflammatory cytokine TNF-α and the osteoclastogenic mediator RANKL to normal levels

  12. Attenuation of Hepatic Graft-versus-host Disease in Allogeneic Recipients of MyD88-deficient Donor Bone Marrow.

    PubMed

    Lim, Ji-Young; Lee, Young-Kwan; Lee, Sung-Eun; Ju, Ji-Min; Park, Gyeongsin; Choi, Eun Young; Min, Chang-Ki

    2015-06-01

    Acute graft-versus-host-disease (GVHD) is characterized by selective damage to the liver, the skin, and the gastrointestinal tract. Following allogeneic hematopoietic stem cell transplantation, donor bone marrow (BM) cells repopulate the immune system of the recipient. We previously demonstrated that the acute intestinal GVHD (iGVHD) mortality rate was higher in MyD88-deficient BM recipients than that in the control BM recipients. In the present study, the role of MyD88 (expressed by donor BM) in the pathophysiology of hepatic GVHD (hGVHD) was examined. Unlike iGVHD, transplantation with MyD88-deficient T-cell depleted (TCD) BM attenuated hGVHD severity and was associated with low infiltration of T cells into the liver of the recipients. Moreover, GVHD hosts, transplanted with MyD88-deficient TCD BM, exhibited markedly reduced expansion of CD11b(+)Gr-1(+) myeloid-derived suppressor cells (MDSC) in the liver. Adoptive injection of the MDSC from wild type mice, but not MyD88-deficient mice, enhanced hepatic T cell infiltration in the MyD88-deficient TCD BM recipients. Pre-treatment of BM donors with LPS increased MDSC levels in the liver of allogeneic wild type BM recipients. In conclusion, hGVHD and iGVHD may occur through various mechanisms based on the presence of MyD88 in the non-T cell compartment of the allograft.

  13. Unfractionated bone marrow cells attenuate paraquat-induced glomerular injury and acute renal failure by modulating the inflammatory response

    PubMed Central

    Gu, Sing-Yi; Yeh, Ti-Yen; Lin, Shih-Yi; Peng, Fu-Chuo

    2016-01-01

    The aim of this study was to evaluate the efficacy of unfractionated bone marrow cells (BMCs) in attenuating acute kidney injury (AKI) induced by paraquat (PQ) in a mouse model. PQ (55 mg/kg BW) was intraperitoneally injected into C57BL/6 female mice to induce AKI, including renal function failure, glomerular damage and renal tubule injury. Glomerular podocytes were the first target damaged by PQ, which led to glomerular injury. Upon immunofluorescence staining, podocytes depletion was validated and accompanied by increased urinary podocin levels, measured on days 1 and 6. A total of 5.4 × 106 BMCs obtained from the same strain of male mice were injected into AKI mice through the tail vein at 3, 24, and 48 hours after PQ administration. As a result, renal function increased, tubular and glomerular injury were ameliorated, podocytes loss improved, and recipient mortality decreased. In addition, BMCs co-treatment decreased the extent of neutrophil infiltration and modulated the inflammatory response by shifting from pro-inflammatory Th1 to an anti-inflammatory Th2 profile, where IL-1β, TNF-α, IL-6 and IFN-γ levels declined and IL-10 and IL-4 levels increased. The present study provides a platform to investigate PQ-induced AKI and repeated BMCs injection represents an efficient therapeutic strategy. PMID:26988026

  14. Attenuation of radiation-induced gastrointestinal damage by epidermal growth factor and bone marrow transplantation in mice.

    PubMed

    Pejchal, Jaroslav; Šinkorová, Zuzana; Tichý, Aleš; Kmochová, Adéla; Ďurišová, Kamila; Kubelková, Klára; Pohanka, Miroslav; Bureš, Jan; Tachecí, Ilja; Kuča, Kamil; Vávrová, Jiřina

    2015-01-01

    We examined the effect of epidermal growth factor (EGF) and bone marrow transplantation (BMT) on gastrointestinal damage after high-dose irradiation of mice. C57Black/6 mice were used. Two survival experiments were performed (12 and 13 Gy; (60)Co, 0.59-0.57 Gy/min). To evaluate BMT and EGF action, five groups were established - 0 Gy, 13 Gy, 13 Gy + EGF (at 2 mg/kg, first dose 24 h after irradiation and then every 48 h), 13 Gy + BMT (5 × 10(6) cells from green fluorescent protein [GFP] syngenic mice, 4 h after irradiation), and 13 Gy + BMT + EGF. Survival data, blood cell counts, gastrointestine and liver parameters and GFP positive cell migration were measured. BMT and EGF (three doses, at 2 mg/kg, administered 1, 3 and 5 days after irradiation) significantly increased survival (13 Gy). In blood, progressive cytopenia was observed with BMT, EGF or their combination having no improving effect early after irradiation. In gastrointestinal system, BMT, EGF and their combination attenuated radiation-induced atrophy and increased regeneration during first week after irradiation with the combination being most effective. Signs of systemic inflammatory reaction were observed 30 days after irradiation. Our data indicate that BMT together with EGF is a promising strategy in the treatment of high-dose whole-body irradiation damage.

  15. Bone-marrow-derived mesenchymal stem cells attenuate cognitive deficits in an endothelin-1 rat model of stroke.

    PubMed

    Lowrance, S A; Fink, K D; Crane, A; Matyas, J; Dey, N D; Matchynski, J J; Thibo, T; Reinke, T; Kippe, J; Hoffman, C; Sandstrom, M; Rossignol, J; Dunbar, G L

    2015-01-01

    Stroke is the third leading cause of death and permanent disability in the United States, often producing long-term cognitive impairments, which are not easily recapitulated in animal models. The goals of this study were to assess whether: (1) the endothelin-1 (ET-1) model of chronic stroke produced discernable cognitive deficits; (2) a spatial operant reversal task (SORT) would accurately measure memory deficits in this model; and (3) bone-marrow-derived mesenchymal stem cells (BMMSCs) could reduce any observed deficits. Rats were given unilateral intracerebral injections of vehicle or ET-1, a stroke-inducing agent, near the middle cerebral artery. Seven days later, they were given intrastriatal injections of BMMSCs or vehicle, near the ischemic penumbra. The cognitive abilities of the rats were assessed on a novel SORT, which was designed to efficiently distinguish cognitive deficits from potential motoric confounds. Rats given ET-1 had significantly more cognitive errors at six weeks post-stroke on the SORT, and that these deficits were attenuated by BMMSC transplants. These findings indicate that: (1) the ET-1 model produces chronic cognitive deficits; (2) the SORT efficiently measures cognitive deficits that are not confounded by motoric impairment; and (3) BMMSCs may be a viable treatment for stroke-induced cognitive dysfunction.

  16. Homocysteine and vitamin B12 status relate to bone turnover markers, broadband ultrasound attenuation, and fractures in healthy elderly people.

    PubMed

    Dhonukshe-Rutten, Rosalie A M; Pluijm, Saskia M F; de Groot, Lisette C P G M; Lips, Paul; Smit, Johannes H; van Staveren, Wija A

    2005-06-01

    Hyperhomocysteinemia may contribute to the development of osteoporosis. The relationship of Hcy and vitamin B12 with bone turnover markers, BUA, and fracture incidence was studied in 1267 subjects of the Longitudinal Aging Study Amsterdam. High Hcy and low vitamin B12 concentrations were significantly associated with low BUA, high markers of bone turnover, and increased fracture risk. Hyperhomocysteinemia may contribute to the development of osteoporosis. Vitamin B12 is closely correlated to homocysteine (Hcy). The main objective of our study was to examine the association of Hcy and vitamin B12 status and the combined effect of these two with broadband ultrasound attenuation (BUA), bone turnover markers, and fracture. Subjects were 615 men and 652 women with a mean age of 76 +/- 6.6 (SD) years of the Longitudinal Aging Study Amsterdam (LASA). At baseline (1995/1996), blood samples were taken after an overnight fast for dairy products. Plasma Hcy was measured with IMx, serum vitamin B12 with competitive immunoassay (IA) luminescence, serum osteocalcin (OC) with immunoradiometric assay (IRMA), and urinary excretion of deoxypyridinoline (DPD) with competitive IA and corrected for creatinine (Cr) concentration. CVs were 4%, 5%, 8%, and 5%, respectively. BUA was assessed in the heel bone twice in both the right and left calcaneus. Mean BUA value was calculated from these four measurements. CV was 3.4%. After baseline measurements in 1995, a 3-year prospective follow-up of fractures was carried out until 1998/1999. Subjects were grouped by using two different approaches on the basis of their vitamin B12 concentration, normal versus low (<200 pM) or lowest quartile (Q1) versus normal quartiles (Q2-Q4), and Hcy concentration, normal versus high (>15 microM) or highest quartile (Q4) versus normal quartiles (Q1-Q3). Analysis of covariance was performed to calculate mean values of BUA, OC, and DPD/Cr(urine) based on the specified categories of Hcy and vitamin B12 and

  17. The Serotonin 2C Receptor Agonist Lorcaserin Attenuates Intracranial Self-Stimulation and Blocks the Reward-Enhancing Effects of Nicotine.

    PubMed

    Zeeb, Fiona D; Higgins, Guy A; Fletcher, Paul J

    2015-07-15

    Lorcaserin, a serotonin (5-hydroxytryptamine, 5-HT) 2C receptor agonist, was recently approved for the treatment of obesity. We previously suggested that 5-HT2C receptor agonists affect reward processes and reduce the rewarding effects of drugs of abuse. Here, we determined whether lorcaserin (1) decreases responding for brain stimulation reward (BSR) and (2) prevents nicotine from enhancing the efficacy of BSR. Rats were trained on the intracranial self-stimulation (ICSS) paradigm to nosepoke for BSR of either the dorsal raphé nucleus or left medial forebrain bundle. In Experiment 1, lorcaserin (0.3-1.0 mg/kg) dose-dependently reduced the efficacy of BSR. This effect was blocked by prior administration of the 5-HT2C receptor antagonist SB242084. In Experiment 2, separate groups of rats received saline or nicotine (0.4 mg/kg) for eight sessions prior to testing. Although thresholds were unaltered in saline-treated rats, nicotine reduced reward thresholds. An injection of lorcaserin (0.3 mg/kg) prior to nicotine prevented the reward-enhancing effect of nicotine across multiple test sessions. These results demonstrated that lorcaserin reduces the rewarding value of BSR and also prevents nicotine from facilitating ICSS. Hence, lorcaserin may be effective in treating psychiatric disorders, including obesity and nicotine addiction, by reducing the value of food or drug rewards.

  18. (+)-UH 232, a partial agonist of the D3 dopamine receptors, attenuates cognitive effects of angiotensin IV and des-Phe(6)-angiotensin IV in rats.

    PubMed

    Braszko, Jan J

    2010-04-01

    We have recently found that postsynaptic D3 dopamine (DA) receptors appear not to participate in the memory enhancing effects of the angiotensin AT4 receptor agonists angiotensin IV (Ang IV) and des-Phe(6)-Ang IV. In this study we evaluated role of the presynaptic DA D3 receptors in these effects. For that purpose effect of (+)-UH 232, a selective D3 DA receptors partial agonist preferring presynaptic sites, on the pro-cognitive action of intracerebroventricularly (icv) injected Ang IV and des-Phe(6)-Ang IV was examined. Male Wistar rats weighing 180-200 g were used. Both peptides given at the dose of 1 nmol facilitated recall of a passive avoidance (PA) behaviour, improved object recognition (OR), and increased apomorphine-induced stereotype behaviour. In the auxiliary tests performed to control for the unspecific influence of motor (open field, OF) and emotional ('plus' maze, PM) effects of our treatments on the results of the memory tests they had either no (OF) or negligible (PM) effects. Intraperitoneal pre-treatment of the animals with an ineffective on its own dose (1 mg/kg) of (+)-UH 232 abolished or markedly diminished effects of both peptides on PA and OR but did not influence enhancement of stereotypy caused by the peptides. 2009 Elsevier B.V. and ECNP. All rights reserved.

  19. [Administration of bone marrow mesenchymal stem cells attenuates inflammation of rats with sepsis].

    PubMed

    Hao, Yufang; Geng, Lixia

    2016-09-01

    Objective To investigate the therapeutic effects of bone marrow-derived mesenchymal stem cells (BMSCs) in rats with sepsis. Methods Forty-eight Wistar rats were divided into blank group, sham group, model group and treatment group. Sepsis model was made using cecum ligation and puncture (CLP). BMSCs were extracted and cultured to the third generation. The rats in the treatment group received BMSCs through a tail vein and the rats in the model group received an equivalent dose of PBS. The survival rate was recorded in each group 72 hours after operation. Pathological changes of lung tissues were observed by HE staining. The mRNA levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), fork head box protein 3 (Foxp3), CC chemokine ligand 2 (CCL2) were tested by quantitative real-time fluorescence PCR. The serum levels of IL-6, IL-17 and TNF-α proteins were detected by ELISA. Results In both blank group and sham group, the survival rate and histological changes of the lungs showed normal; no bacteria were found growing in rats' blood culture; IL-6, IL-17, TNF-α, CCL2, Foxp3 mRNA and IL-6, IL-17, TNF-α protein levels had no significant differences. In the model group, the survival rate of rats was obviously lower than that of the sham group; the pathological changes of the lungs were significant; any amount of enterobacteria were seen growing in rats' blood culture; IL-6, IL-17, TNF-α, CCL2 mRNA and protein expression levels were apparently higher than those of sham group, while Foxp3 mRNA expression level was obviously lower than that of sham group. In the treatment group, the survival rate was significantly higher than that of the model group; the pathological changes of the lung tissues were evidently eased; IL-6, IL-17, TNF-α, CCL2 mRNA and protein expression levels significantly decreased compared with the model group, while Foxp3 mRNA expression level significantly increased compared with the model group. Conclusion BMSCs injection increases the

  20. Correlation of signal attenuation-based quantitative magnetic resonance imaging with quantitative computed tomographic measurements of subchondral bone mineral density in metacarpophalangeal joints of horses.

    PubMed

    Olive, Julien; d'Anjou, Marc-André; Alexander, Kate; Beauchamp, Guy; Theoret, Christine L

    2010-04-01

    To evaluate the ability of signal attenuation-based quantitative magnetic resonance imaging (QMRI) to estimate subchondral bone mineral density (BMD) as assessed via quantitative computed tomography (QCT) in osteoarthritic joints of horses. 20 metacarpophalangeal joints from 10 horse cadavers. Magnetic resonance (MR) images (dorsal and transverse T1-weighted gradient recalled echo [GRE] and dorsal T2*-weighted GRE fast imaging employing steady-state acquisition [T2*-FIESTA]) and transverse single-slice computed tomographic (CT) images of the joints were acquired. Magnetic resonance signal intensity (SI) and CT attenuation were quantified in 6 regions of interest (ROIs) in the subchondral bone of third metacarpal condyles. Separate ROIs were established in the air close to the joint and used to generate corrected ratios and SIs. Computed tomographic attenuation was corrected by use of a calibration phantom to obtain a K(2)HPO(4)-equivalent density of bone. Correlations between QMRI performed with different MR imaging sequences and QCT measurements were evaluated. The intraobserver repeatability of ROI measurements was tested for each modality. Measurement repeatability was excellent for QCT (R(2) = 98.3%) and QMRI (R(2) = 98.8%). Transverse (R(2) = 77%) or dorsal (R(2) = 77%) T1-weighted GRE and QCT BMD measurements were negatively correlated, as were dorsal T2*-FIESTA and QCT (R(2) = 80%) measurements. Decreased bone SI during MR imaging linearly reflected increased BMD. Results of this ex vivo study suggested that signal attenuation-based QMRI was a reliable, clinically applicable method for indirect estimation of subchondral BMD in osteoarthritic metacarpophalangeal joints of horses.

  1. k-space sampling optimization for ultrashort TE imaging of cortical bone: Applications in radiation therapy planning and MR-based PET attenuation correction

    PubMed Central

    Hu, Lingzhi; Su, Kuan-Hao; Pereira, Gisele C.; Grover, Anu; Traughber, Bryan; Traughber, Melanie; Muzic, Raymond F.

    2014-01-01

    Purpose: The ultrashort echo-time (UTE) sequence is a promising MR pulse sequence for imaging cortical bone which is otherwise difficult to image using conventional MR sequences and also poses strong attenuation for photons in radiation therapy and PET imaging. The authors report here a systematic characterization of cortical bone signal decay and a scanning time optimization strategy for the UTE sequence through k-space undersampling, which can result in up to a 75% reduction in acquisition time. Using the undersampled UTE imaging sequence, the authors also attempted to quantitatively investigate the MR properties of cortical bone in healthy volunteers, thus demonstrating the feasibility of using such a technique for generating bone-enhanced images which can be used for radiation therapy planning and attenuation correction with PET/MR. Methods: An angularly undersampled, radially encoded UTE sequence was used for scanning the brains of healthy volunteers. Quantitative MR characterization of tissue properties, including water fraction and R2∗ = 1/T2∗, was performed by analyzing the UTE images acquired at multiple echo times. The impact of different sampling rates was evaluated through systematic comparison of the MR image quality, bone-enhanced image quality, image noise, water fraction, and R2∗ of cortical bone. Results: A reduced angular sampling rate of the UTE trajectory achieves acquisition durations in proportion to the sampling rate and in as short as 25% of the time required for full sampling using a standard Cartesian acquisition, while preserving unique MR contrast within the skull at the cost of a minimal increase in noise level. The R2∗ of human skull was measured as 0.2–0.3 ms−1 depending on the specific region, which is more than ten times greater than the R2∗ of soft tissue. The water fraction in human skull was measured to be 60%–80%, which is significantly less than the >90% water fraction in brain. High-quality, bone

  2. k-space sampling optimization for ultrashort TE imaging of cortical bone: Applications in radiation therapy planning and MR-based PET attenuation correction

    SciTech Connect

    Hu, Lingzhi E-mail: raymond.muzic@case.edu; Traughber, Melanie; Su, Kuan-Hao; Pereira, Gisele C.; Grover, Anu; Traughber, Bryan; Muzic, Raymond F. Jr. E-mail: raymond.muzic@case.edu

    2014-10-15

    Purpose: The ultrashort echo-time (UTE) sequence is a promising MR pulse sequence for imaging cortical bone which is otherwise difficult to image using conventional MR sequences and also poses strong attenuation for photons in radiation therapy and PET imaging. The authors report here a systematic characterization of cortical bone signal decay and a scanning time optimization strategy for the UTE sequence through k-space undersampling, which can result in up to a 75% reduction in acquisition time. Using the undersampled UTE imaging sequence, the authors also attempted to quantitatively investigate the MR properties of cortical bone in healthy volunteers, thus demonstrating the feasibility of using such a technique for generating bone-enhanced images which can be used for radiation therapy planning and attenuation correction with PET/MR. Methods: An angularly undersampled, radially encoded UTE sequence was used for scanning the brains of healthy volunteers. Quantitative MR characterization of tissue properties, including water fraction and R2{sup ∗} = 1/T2{sup ∗}, was performed by analyzing the UTE images acquired at multiple echo times. The impact of different sampling rates was evaluated through systematic comparison of the MR image quality, bone-enhanced image quality, image noise, water fraction, and R2{sup ∗} of cortical bone. Results: A reduced angular sampling rate of the UTE trajectory achieves acquisition durations in proportion to the sampling rate and in as short as 25% of the time required for full sampling using a standard Cartesian acquisition, while preserving unique MR contrast within the skull at the cost of a minimal increase in noise level. The R2{sup ∗} of human skull was measured as 0.2–0.3 ms{sup −1} depending on the specific region, which is more than ten times greater than the R2{sup ∗} of soft tissue. The water fraction in human skull was measured to be 60%–80%, which is significantly less than the >90% water fraction in

  3. The peroxisome proliferator-activated receptor-alpha (PPAR-alpha) agonist, AVE8134, attenuates the progression of heart failure and increases survival in rats.

    PubMed

    Linz, Wolfgang; Wohlfart, Paulus; Baader, Manuel; Breitschopf, Kristin; Falk, Eugen; Schäfer, Hans-Ludwig; Gerl, Martin; Kramer, Werner; Rütten, Hartmut

    2009-07-01

    To investigate the efficacy of the peroxisome proliferator-activated receptor-alpha (PPARalpha) agonist, AVE8134, in cellular and experimental models of cardiac dysfunction and heart failure. In Sprague Dawley rats with permanent ligation of the left coronary artery (post-MI), AVE8134 was compared to the PPARgamma agonist rosiglitazone and in a second study to the ACE inhibitor ramipril. In DOCA-salt sensitive rats, efficacy of AVE8134 on cardiac hypertrophy and fibrosis was investigated. Finally, AVE8134 was administered to old spontaneously hypertensive rats (SHR) at a non-blood pressure lowering dose with survival as endpoint. In cellular models, we studied AVE8134 on hypertrophy in rat cardiomyocytes, nitric oxide signaling in human endothelial cells (HUVEC) and LDL-uptake in human MonoMac-6 cells. In post-MI rats, AVE8134 dose-dependently improved cardiac output, myocardial contractility and relaxation and reduced lung and left ventricular weight and fibrosis. In contrast, rosiglitazone exacerbated cardiac dysfunction. Treatment at AVE8134 decreased plasma proBNP and arginine and increased plasma citrulline and urinary NOx/creatinine ratio. In DOCA rats, AVE8134 prevented development of high blood pressure, myocardial hypertrophy and cardiac fibrosis, and ameliorated endothelial dysfunction. Compound treatment increased cardiac protein expression and phosphorylation of eNOS. In old SHR, treatment with a low dose of AVE8134 improved cardiac and vascular function and increased life expectancy without lowering blood pressure. AVE8134 reduced phenylephrine-induced hypertrophy in adult rat cardiomyocytes. In HUVEC, Ser-1177-eNOS phosphorylation but not eNOS expression was increased. In monocytes, AVE8134 increased the expression of CD36 and the macrophage scavenger receptor 1, resulting in enhanced uptake of oxidized LDL. The PPARalpha agonist AVE8134 prevents post-MI myocardial hypertrophy, fibrosis and cardiac dysfunction. AVE8134 has beneficial effects against

  4. The selective alpha7 agonist GTS-21 attenuates cytokine production in human whole blood and human monocytes activated by ligands for TLR2, TLR3, TLR4, TLR9, and RAGE.

    PubMed

    Rosas-Ballina, Mauricio; Goldstein, Richard S; Gallowitsch-Puerta, Margot; Yang, Lihong; Valdés-Ferrer, Sergio Iván; Patel, Nirav B; Chavan, Sangeeta; Al-Abed, Yousef; Yang, Huan; Tracey, Kevin J

    2009-01-01

    The cholinergic antiinflammatory pathway modulates inflammatory cytokine production through a mechanism dependent on the vagus nerve and the alpha7 subunit of the nicotinic acetylcholine receptor. GTS-21 [3-(2,4-dimethoxybenzylidene) anabaseine], a selective alpha7 agonist, inhibits inflammatory cytokine production in murine and human macrophages and in several models of inflammatory disease in vivo, but to date its antiinflammatory efficacy in human monocytes has not been characterized. We report here our findings that GTS-21 attenuates tumor necrosis factor (TNF) and interleukin 1beta levels in human whole blood activated by exposure to endotoxin. GTS-21 inhibited TNF production in endotoxin-stimulated primary human monocytes in vitro at the transcriptional level. The suppressive effect of GTS-21 was more potent than nicotine in whole blood and monocytes. Furthermore, GTS-21 attenuated TNF production in monocytes stimulated with peptidoglycan, polyinosinic-polycytidylic acid, CpG, HMGB1 (high-mobility group box 1 protein), and advanced glycation end product-modified albumin. GTS-21 decreased TNF levels in endotoxin-stimulated whole blood obtained from patients with severe sepsis. These findings establish the immunoregulatory effect of GTS-21 on human monocytes, and indicate the potential benefits of further exploration of GTS-21's therapeutic uses in human inflammatory disease.

  5. TLR-7 agonist attenuates airway reactivity and inflammation through Nrf2-mediated antioxidant protection in a murine model of allergic asthma.

    PubMed

    Nadeem, Ahmed; Siddiqui, Nahid; Al-Harbi, Naif O; Al-Harbi, Mohammed M; Ahmad, Sheikh F

    2016-04-01

    Toll-like receptors (TLRs) through innate immune system recognize pathogen associated molecular patterns and play an important role in host defense against bacteria, fungi and viruses. TLR-7 is responsible for sensing single stranded nucleic acids of viruses but its activation has been shown to be protective in mouse models of asthma. The NADPH oxidase (NOX) enzymes family mainly produces reactive oxygen species (ROS) in the lung and is involved in regulation of airway inflammation in response to TLRs activation. However, NOX-4 mediated signaling in response to TLR-7 activation in a mouse model of allergic asthma has not been explored previously. Therefore, this study investigated the role TLR-7 activation and downstream oxidant-antioxidant signaling in a murine model of asthma. Mice were sensitized with ovalbumin (OVA) intraperitoneally and treated with TLR-7 agonist, resiquimod (RSQ) intranasally before each OVA challenge from days 14 to 16. Mice were then assessed for airway reactivity, inflammation, and NOX-4 and nuclear factor E2-related factor 2 (Nrf2) related signaling [inducible nitric oxide synthase (iNOS), nitrotyrosine, lipid peroxides and copper/zinc superoxide dismutase (Cu/Zn SOD)]. Treatment with RSQ reduced allergen induced airway reactivity and inflammation. This was paralleled by a decrease in ROS which was due to induction of Nrf2 and Cu/Zn SOD in RSQ treated group. Inhibition of MyD88 reversed RSQ-mediated protective effects on airway reactivity/inflammation due to reduction in Nrf2 signaling. SOD inhibition produced effects similar to MyD88 inhibition. The current study suggests that TLR-7 agonist is beneficial and may be developed into a therapeutic option in allergic asthma.

  6. The ghrelin receptor agonist HM01 mimics the neuronal effects of ghrelin in the arcuate nucleus and attenuates anorexia-cachexia syndrome in tumor-bearing rats.

    PubMed

    Borner, Tito; Loi, Laura; Pietra, Claudio; Giuliano, Claudio; Lutz, Thomas A; Riediger, Thomas

    2016-07-01

    The gastric hormone ghrelin positively affects energy balance by increasing food intake and reducing energy expenditure. Ghrelin mimetics are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to characterize the action of the nonpeptidergic ghrelin receptor agonist HM01 on neuronal function, energy homeostasis and muscle mass in healthy rats and to evaluate its possible usefulness for the treatment of CACS in a rat tumor model. Using extracellular single-unit recordings, we tested whether HM01 mimics the effects of ghrelin on neuronal activity in the arcuate nucleus (Arc). Furthermore, we assessed the effect of chronic HM01 treatment on food intake (FI), body weight (BW), lean and fat volumes, and muscle mass in healthy rats. Using a hepatoma model, we investigated the possible beneficial effects of HM01 on tumor-induced anorexia, BW loss, muscle wasting, and metabolic rate. HM01 (10(-7)-10(-6) M) mimicked the effect of ghrelin (10(-8) M) by increasing the firing rate in 76% of Arc neurons. HM01 delivered chronically for 12 days via osmotic minipumps (50 μg/h) increased FI in healthy rats by 24%, paralleled by increased BW, higher fat and lean volumes, and higher muscle mass. Tumor-bearing rats treated with HM01 had 30% higher FI than tumor-bearing controls and were protected against BW loss. HM01 treatment resulted in higher muscle mass and fat mass. Moreover, tumor-bearing rats reduced their metabolic rate following HM01 treatment. Our studies substantiate the possible therapeutic usefulness of ghrelin receptor agonists like HM01 for the treatment of CACS and possibly other forms of disease-related anorexia and cachexia. Copyright © 2016 the American Physiological Society.

  7. MR-based attenuation correction for PET/MRI neurological studies with continuous-valued attenuation coefficients for bone through a conversion from R2* to CT-Hounsfield units.

    PubMed

    Juttukonda, Meher R; Mersereau, Bryant G; Chen, Yasheng; Su, Yi; Rubin, Brian G; Benzinger, Tammie L S; Lalush, David S; An, Hongyu

    2015-05-15

    MR-based correction for photon attenuation in PET/MRI remains challenging, particularly for neurological applications requiring quantitation of data. Existing methods are either not sufficiently accurate or are limited by the computation time required. The goal of this study was to develop an MR-based attenuation correction method that accurately separates bone tissue from air and provides continuous-valued attenuation coefficients for bone. PET/MRI and CT datasets were obtained from 98 subjects (mean age [±SD]: 66yrs [±9.8], 57 females) using an IRB-approved protocol and with informed consent. Subjects were injected with 352±29MBq of (18)F-Florbetapir tracer, and PET acquisitions were begun either immediately or 50min after injection. CT images of the head were acquired separately using a PET/CT system. Dual echo ultrashort echo-time (UTE) images and two-point Dixon images were acquired. Regions of air were segmented via a threshold of the voxel-wise multiplicative inverse of the UTE echo 1 image. Regions of bone were segmented via a threshold of the R2* image computed from the UTE echo 1 and UTE echo 2 images. Regions of fat and soft tissue were segmented using fat and water images decomposed from the Dixon images. Air, fat, and soft tissue were assigned linear attenuation coefficients (LACs) of 0, 0.092, and 0.1cm(-1), respectively. LACs for bone were derived from a regression analysis between corresponding R2* and CT values. PET images were reconstructed using the gold standard CT method and the proposed CAR-RiDR method. The RiDR segmentation method produces mean Dice coefficient±SD across subjects of 0.75±0.05 for bone and 0.60±0.08 for air. The CAR model for bone LACs greatly improves accuracy in estimating CT values (28.2%±3.0 mean error) compared to the use of a constant CT value (46.9%±5.8, p<10(-6)). Finally, the CAR-RiDR method provides a low whole-brain mean absolute percent-error (MAPE±SD) in PET reconstructions across subjects of 2.55%±0

  8. The blocking of uPAR suppresses lipopolysaccharide‐induced inflammatory osteoclastogenesis and the resultant bone loss through attenuation of integrin β3/Akt pathway

    PubMed Central

    Ishisaki, Akira; Miyashita, Mei; Matsuo, Osamu

    2016-01-01

    Abstract Introduction Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis, cause the bone destruction by promotion of the differentiation of monocyte/macrophage lineage cells into mature osteoclasts (OCs) with active bone‐resorbing character. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated the role of urokinase plasminogen activator receptor (uPAR) in the bone destruction caused by chronic inflammation. Methods We investigated that the effect of uPAR on inflammatory OC formation induced by lipopolysaccharide (LPS) in inflammatory diseases. Results We found that the LPS more weakly induced OC formation and the resultant bone loss in uPAR‐deficient mice than in wild‐type mice. Additionally, we demonstrated that uPAR significantly potentiated LPS‐induced OC formation of RAW264.7 mouse monocyte/macrophage linage cells in integrin β3/Akt‐dependent manner. Moreover, we showed that the blocking of uPAR function by the administration of anti‐uPAR neutralizing antibody significantly attenuated the LPS‐induced OC formation and the resultant bone loss in mice. Conclusions These results strongly suggest that uPAR negatively regulates the LPS‐induced inflammatory OC formation and the resultant bone loss mediated through the integrin β3/Akt pathway. Our findings partly clarify the molecular mechanisms underlying bone destruction caused by chronic inflammatory diseases, and would benefit research on identifying antibody therapy for the treatment of these diseases. PMID:27621816

  9. Fetal ethanol exposure attenuates aversive oral effects of TrpV1, but not TrpA1 agonists in rats.

    PubMed

    Glendinning, John I; Simons, Yael M; Youngentob, Lisa; Youngentob, Steven L

    2012-03-01

    In humans, fetal ethanol exposure is highly predictive of adolescent ethanol use and abuse. Prior work in our labs indicated that fetal ethanol exposure results in stimulus-induced chemosensory plasticity in the taste and olfactory systems of adolescent rats. In particular, we found that increased ethanol acceptability could be attributed, in part, to an attenuated aversion to ethanol's aversive odor and quinine-like bitter taste quality. Here, we asked whether fetal ethanol exposure also alters the oral trigeminal response of adolescent rats to ethanol. We focused on two excitatory ligand-gated ion channels, TrpV1 and TrpA1, which are expressed in oral trigeminal neurons and mediate the aversive orosensory response to many chemical irritants. To target TrpV1, we used capsaicin, and to target TrpA1, we used allyl isothiocyanate (or mustard oil). We assessed the aversive oral effects of ethanol, together with capsaicin and mustard oil, by measuring short-term licking responses to a range of concentrations of each chemical. Experimental rats were exposed in utero by administering ethanol to dams through a liquid diet. Control rats had ad libitum access to an iso-caloric iso-nutritive liquid diet. We found that fetal ethanol exposure attenuated the oral aversiveness of ethanol and capsaicin, but not mustard oil, in adolescent rats. Moreover, the increased acceptability of ethanol was directly related to the reduced aversiveness of the TrpV1-mediated orosensory input. We propose that fetal ethanol exposure increases ethanol avidity not only by making ethanol smell and taste better, but also by attenuating ethanol's capsaicin-like burning sensations.

  10. The GLP-1 agonist exendin-4 attenuates self-administration of sweetened fat on fixed and progressive ratio schedules of reinforcement in rats.

    PubMed

    Bernosky-Smith, Kimberly A; Stanger, David B; Trujillo, Alexandria J; Mitchell, Luke R; España, Rodrigo A; Bass, Caroline E

    2016-03-01

    GLP-1 agonists such as exendin-4 (EX4) are used in the treatment of type-2 diabetes and have the additional benefit of promoting weight loss. GLP-1 agonists decrease feeding through peripheral effects, but recent evidence suggests they may also influence sweet or high fat preference, as well as motivation to obtain these tastants. Yet it remains unclear how GLP-1-induced alterations in food preference influences decreases in overall feeding. The current study sought to determine if EX4 affects the reinforcing strength and consumption of a highly palatable sweet/fat reinforcer. Rats were trained to self-administer sweetened vegetable shortening (SVS) under fixed (FR) and progressive ratio (PR) schedules of reinforcement. EX4 (0.3-2.4μg/kg, i.p.) administered one hour prior to operant sessions significantly reduced responses for SVS under both FR and PR schedules, although the lowest active dose (0.6μg/kg) significantly suppressed FR responding only. EX4 also dose dependently decreased locomotor activity (0.6-2.4μg/kg doses), but did not enhance acute kaolin intake, suggesting that nausea did not influence the self-administration results. Analysis of ED50 values show that EX4 is more effective at inhibiting FR responding versus PR, indicating that EX4 may have more potent effects on amount consumed versus motivation for SVS. Although EX4 caused generalized locomotor suppression, these results do not fully explain the decreases in operant responding. For example, a dose of EX4 (0.6μg/kg) that significantly suppressed locomotor activity did not affect the mean total number of lever presses during PR sessions (59±15), although it did significantly reduce lever presses during FR sessions (21±3). In addition, the pattern of intake was constant at the beginning of the sessions in both PR and FR schedules, regardless of the dose. Together these data suggest that EX4 inhibits consumption of a palatable high sweet/high fat reinforcer potentially through altering satiety.

  11. MO-G-17A-03: MR-Based Cortical Bone Segmentation for PET Attenuation Correction with a Non-UTE 3D Fast GRE Sequence

    SciTech Connect

    Ai, H; Pan, T; Hwang, K

    2014-06-15

    Purpose: To determine the feasibility of identifying cortical bone on MR images with a short-TE 3D fast-GRE sequence for attenuation correction of PET data in PET/MR. Methods: A water-fat-bone phantom was constructed with two pieces of beef shank. MR scans were performed on a 3T MR scanner (GE Discovery™ MR750). A 3D GRE sequence was first employed to measure the level of residual signal in cortical bone (TE{sub 1}/TE{sub 2}/TE{sub 3}=2.2/4.4/6.6ms, TR=20ms, flip angle=25°). For cortical bone segmentation, a 3D fast-GRE sequence (TE/TR=0.7/1.9ms, acquisition voxel size=2.5×2.5×3mm{sup 3}) was implemented along with a 3D Dixon sequence (TE{sub 1}/TE{sub 2}/TR=1.2/2.3/4.0ms, acquisition voxel size=1.25×1.25×3mm{sup 3}) for water/fat imaging. Flip angle (10°), acquisition bandwidth (250kHz), FOV (480×480×144mm{sup 3}) and reconstructed voxel size (0.94×0.94×1.5mm{sup 3}) were kept the same for both sequences. Soft tissue and fat tissue were first segmented on the reconstructed water/fat image. A tissue mask was created by combining the segmented water/fat masks, which was then applied on the fast-GRE image (MRFGRE). A second mask was created to remove the Gibbs artifacts present in regions in close vicinity to the phantom. MRFGRE data was smoothed with a 3D anisotropic diffusion filter for noise reduction, after which cortical bone and air was separated using a threshold determined from the histogram. Results: There is signal in the cortical bone region in the 3D GRE images, indicating the possibility of separating cortical bone and air based on signal intensity from short-TE MR image. The acquisition time for the 3D fast-GRE sequence was 17s, which can be reduced to less than 10s with parallel imaging. The attenuation image created from water-fat-bone segmentation is visually similar compared to reference CT. Conclusion: Cortical bone and air can be separated based on intensity in MR image with a short-TE 3D fast-GRE sequence. Further research is required

  12. Synergistic attenuation of ovariectomy-induced bone loss by combined use of fish oil and 17β-oestradiol.

    PubMed

    Jin, Youri; Lee, Myoungsook; Park, Yongsoon

    2017-02-01

    Oestrogen and n-3 PUFA, especially EPA and DHA, have been reported to have beneficial effects on bone loss. Thus, the purpose of the present study was to investigate the synergistic bone-protective mechanism of combined treatments of EPA+DHA supplementation and oestrogen injection in ovariectomised rats. Rats were fed a modified American Institute of Nutrition-93G diet with 0 %, 1 % or 2 % n-3 PUFA (EPA+DHA) relative to the total energy intake for 12 weeks. Rats were surgically ovariectomised at week 8, and after a 1-week recovery period rats were injected with either 17β-oestradiol-3-benzoate (E2) or maize oil for the last 3 weeks. Combined use of n-3 PUFA and E2 synergistically increased femoral cortical bone volume, bone mineral content and the bone expression of runt-related transcription factor 2 (RUNX2), but decreased the bone expression of IL-1β. Both n-3 PUFA and E2 decreased the bone expressions of IL-7, TNF-α and PPAR-γ, and increased the bone expression of oestrogen receptor-α. n-3 PUFA in the presence of E2 and E2 alone significantly decreased the bone expressions of IL-1β and IL-6 and increased the bone expression of RUNX2. E2 significantly decreased the serum levels of bone turnover markers and the bone expression of receptor activator of NF-κB ligand, but decreased the bone expression of osteoprotegerin. The combined use of n-3 PUFA and E2 exerted synergistic bone-protective efficacy through up-regulation of RUNX2, an essential transcription factor for bone formation, as well as the suppression of bone-resorbing cytokine IL-1β.

  13. The D1 dopamine receptor agonist, SKF83959, attenuates hydrogen peroxide-induced injury in RGC-5 cells involving the extracellular signal-regulated kinase/p38 pathways

    PubMed Central

    Li, Guang-Yu; Li, Ting; Fan, Bin; Zheng, Yong-Chen

    2012-01-01

    Purpose Oxidative stress is widely implicated in the death of retinal ganglion cells associated with various optic neuropathies. Agonists of the dopamine D1 receptor have recently been found to be potentially neuroprotective against oxidative stress–induced injury. The goal of this study was to investigate whether SKF83959, a next-generation high-affinity D1 receptor agonist, could protect retinal ganglion cell 5 (RGC-5) cells from H2O2-induced damage and the molecular mechanism involved. Methods We examined expression of the D1 receptor in RGC-5 cells with reverse-transcription–PCR and immunoblotting and assessed neuroprotection using propidium iodide staining and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In addition, we monitored the activation and involvement of members of mitogen-activated protein kinase family, extracellular signal-regulated kinase (ERK), p38 and c-Jun NH2-terminal kinase, with western blot and specific inhibitors. Results We found that the D1 receptor was expressed in RGC-5 cells, but the sequence analysis suggested this cell line is from mouse and not rat origin. SKF83959 exhibited a remarkable neuroprotective effect on H2O2-damaged RGC-5 cells, which was blocked by the specific D1 receptor antagonist, SCH23390. ERK and p38 were activated by SKF83959, and pretreatment with their inhibitors U0126 and SB203580, respectively, significantly blunted the SKF83959-induced cytoprotection. However, the specific c-Jun NH2-terminal kinase inhibitor, SP600125, had no effect on the SKF83959-induced protection. Conclusions We conclude that SKF83959 attenuates hydrogen peroxide–induced injury in RGC-5 cells via a mechanism involving activation of the ERK and p38 pathways and the D1 receptor is a potential molecular target for developing neuroprotective drugs. PMID:23233790

  14. High-fat diet enhances and plasminogen activator inhibitor-1 deficiency attenuates bone loss in mice with Lewis Lung carcinoma

    USDA-ARS?s Scientific Manuscript database

    This study determined the effects of a high-fat diet and plasminogen activator inhibitor-1 deficiency (PAI-1-/-) on bone structure in mice bearing Lewis lung carcinoma (LLC) in lungs. Reduction in bone volume fraction (BV/TV) by 22% and 21%, trabecular number (Tb.N) by 8% and 4% and bone mineral de...

  15. Bone

    NASA Astrophysics Data System (ADS)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  16. The antimigraine 5-HT1B/1D receptor agonists, sumatriptan, zolmitriptan and dihydroergotamine, attenuate pain-related behaviour in a rat model of trigeminal neuropathic pain

    PubMed Central

    Kayser, Valérie; Aubel, Bertrand; Hamon, Michel; Bourgoin, Sylvie

    2002-01-01

    Peripheral lesion to the trigeminal nerve may induce severe pain states. Several lines of evidence have suggested that the antimigraine effect of the triptans with 5-HT1B/1D receptor agonist properties may result from inhibition of nociceptive transmission in the spinal nucleus of the trigeminal nerve by these drugs. On this basis, we have assessed the potential antinociceptive effects of sumatriptan and zolmitriptan, compared to dihydroergotamine (DHE), in a rat model of trigeminal neuropathic pain. Chronic constriction injury was produced by two loose ligatures of the infraorbital nerve on the right side. Responsiveness to von Frey filament stimulation of the vibrissal pad was used to evaluate allodynia. Two weeks after ligatures, rats with a chronic constriction of the right infraorbital nerve displayed bilateral mechanical hyper-responsiveness to von Frey filament stimulation of the vibrissal pad with a mean threshold of 0.38±0.04 g on the injured side and of 0.43±0.04 g on the contralateral (left) side (versus ⩾12.5 g on both sides in the same rats prior to nerve constriction injury). Sumatriptan at a clinically relevant dose (100 μg kg−1, s.c.) led to a significant reduction of the mechanical allodynia-like behaviour on both the injured and the contralateral sides (peak-effects 6.3±1.1 g and 4.4±0.7 g, respectively). A more pronounced effect was obtained with zolmitriptan (100 μg kg−1, s.c.) (peak-effects: 7.4±0.9 g and 3.2±1.3 g) whereas DHE (50–100 μg kg−1, i.v.) was less active (peak-effect ∼1.5 g). Subcutaneous pretreatment with the 5-HT1B/1D receptor antagonist, GR 127935 (3 mg kg−1), prevented the anti-allodynia-like effects of triptans and DHE. Pretreatment with the 5-HT1A receptor antagonist, WAY 100635 (2 mg kg−1, s.c.), did not alter the effect of triptans but significantly enhanced that of DHE (peak effect 4.3±0.5 g). In a rat model of peripheral neuropathic pain, which consisted of a unilateral loose constriction of the

  17. Traumatic Brain Injury-Induced Cognitive and Histological Deficits Are Attenuated by Delayed and Chronic Treatment with the 5-HT1A-Receptor Agonist Buspirone

    PubMed Central

    Olsen, Adam S.; Sozda, Christopher N.; Cheng, Jeffrey P.; Hoffman, Ann N.

    2012-01-01

    Abstract The aim of this study was to evaluate the potential efficacy of the serotonin1A (5-HT1A) receptor agonist buspirone (BUS) on behavioral and histological outcome after traumatic brain injury (TBI). Ninety-six isoflurane-anesthetized adult male rats were randomized to receive either a controlled cortical impact or sham injury, and then assigned to six TBI and six sham groups receiving one of five doses of BUS (0.01, 0.05, 0.1, 0.3, or 0.5 mg/kg) or saline vehicle (VEH, 1.0 mL/kg). Treatments began 24 h after surgery and were administered intraperitoneally once daily for 3 weeks. Motor function (beam-balance/beam-walk tests) and spatial learning/memory (Morris water maze) were assessed on post-operative days 1–5 and 14–19, respectively. Morphologically intact CA1/CA3 cells and cortical lesion volume were quantified at 3 weeks. No differences were observed among the BUS and VEH sham groups in any end-point measure and thus the data were pooled. Regarding the TBI groups, repeated-measures ANOVAs revealed that the 0.3 mg/kg dose of BUS enhanced cognitive performance relative to VEH and the other BUS doses (p<0.05), but did not significantly impact motor function. Moreover, the same dose conferred selective histological protection as evidenced by smaller cortical lesions, but not greater CA1/CA3 cell survival. No significant behavioral or histological differences were observed among the other BUS doses versus VEH. These data indicate that BUS has a narrow therapeutic dose response, and that 0.3 mg/kg is optimal for enhancing spatial learning and memory in this model of TBI. BUS may have potential as a novel pharmacotherapy for clinical TBI. PMID:22416854

  18. Olanzapine-activated AMPK signaling in the dorsal vagal complex is attenuated by histamine H1 receptor agonist in female rats.

    PubMed

    He, Meng; Zhang, Qingsheng; Deng, Chao; Wang, Hongqin; Huang, Xu-Feng

    2014-12-01

    Weight gain and its related metabolic disorders are major side effects associated with second generation antipsychotic drug treatment. The dorsal vagal complex (DVC) and AMP-activated protein kinase (AMPK) are implicated in the regulation of food intake and body weight. Blocking the histamine H1 receptor contributes to antipsychotic-induced weight gain. The present study investigated the time-dependent effect of olanzapine treatment (8, 16, and 36 d) on DVC AMPK signaling in olanzapine-induced weight gain and whether these changes are associated with olanzapine-induced H1 receptor antagonism. During the 8-day olanzapine treatment, the rats were hyperphagic and rapidly gained weight. The phosphorylation of AMPK (pAMPK) (activated AMPK) as well as its directly downstream phospho-acetyl-coenzyme A carboxylase was significantly increased. The pAMPK/AMPK ratio, an indicator of AMPK activity, was significantly positively correlated with feeding efficiency and weight gain. As treatment was prolonged (16 and 36 d of olanzapine treatment), the rats were no longer hyperphagic, and there were no longer any changes in DVC AMPK signaling. Although the DVC H1 receptor protein expression was not significantly altered by olanzapine, the pAMPK expression was significantly positively correlated with the H1 receptor level after the 8-, 16-, and 36-day olanzapine treatments. Moreover, we showed that an H1 receptor agonist, 2-(3-trifluoromethylphenyl) histamine, significantly inhibited the olanzapine-induced hyperphagia and DVC AMPK activation in a dose-dependent manner. These results suggest a time-dependent role of DVC AMPK in olanzapine-induced obesity. Thus, olanzapine-induced DVC AMPK activation may be at least partially related to olanzapine's antagonistic effect on the H1 receptor.

  19. Rosiglitazone, a Peroxisome Proliferator-Activated Receptor (PPAR)-γ Agonist, Attenuates Inflammation Via NF-κB Inhibition in Lipopolysaccharide-Induced Peritonitis.

    PubMed

    Zhang, Yun-Fang; Zou, Xun-Liang; Wu, Jun; Yu, Xue-Qing; Yang, Xiao

    2015-12-01

    We assessed the anti-inflammatory effect of peroxisome proliferator-activated receptor (PPAR)-γ agonist, rosiglitazone, in a lipopolysaccharide (LPS)-induced peritonitis rat model. LPS was intraperitoneally injected into rats to establish peritonitis model. Male Sprague-Dawley (SD) rats were assigned to normal saline (the solvent of LPS), LPS, rosiglitazone plus LPS, and rosiglitazone alone. A simple peritoneal equilibrium test was performed with 20 ml 4.25 % peritoneal dialysis fluid. We measured the leukocyte count in dialysate and ultrafiltration volume. Peritoneal membrane histochemical staining was performed, and peritoneal thickness was assessed. CD40 and intercellular adhesion molecule-1 messenger RNA (ICAM-1 mRNA) levels in rat visceral peritoneum were detected by reverse transcription (RT)-PCR. IL-6 in rat peritoneal dialysis effluent was measured using enzyme-linked immunosorbent assay. The phosphorylation of NF-κB-p65 and IκBα was analyzed by Western blot. LPS administration resulted in increased peritoneal thickness and decreased ultrafiltration volume. Rosiglitazone pretreatment significantly decreased peritoneal thickness. In addition to CD40 and ICAM-1 mRNA expression, the IL-6, p-p65, and p-IκBα protein expressions were enhanced in LPS-administered animals. Rosiglitazone pretreatment significantly decreased ICAM-1 mRNA upregulation, secretion of IL-6 protein, and phosphorylation of NF-κB-p65 and IκBα without decreasing CD40 mRNA expression. Rosiglitazone has a protective effect in peritonitis, simultaneously decreasing NF-κB phosphorylation, suggesting that NF-κB signaling pathway mediated peritoneal inflammation induced by LPS. PPAR-γ might be considered a potential therapeutic target against peritonitis.

  20. The cannabinoid receptor 2 agonist, β-caryophyllene, reduced voluntary alcohol intake and attenuated ethanol-induced place preference and sensitivity in mice.

    PubMed

    Al Mansouri, Shamma; Ojha, Shreesh; Al Maamari, Elyazia; Al Ameri, Mouza; Nurulain, Syed M; Bahi, Amine

    2014-09-01

    Several recent studies have suggested that brain CB2 cannabinoid receptors play a major role in alcohol reward. In fact, the implication of cannabinoid neurotransmission in the reinforcing effects of ethanol (EtOH) is becoming increasingly evident. The CB2 receptor agonist, β-caryophyllene (BCP) was used to investigate the role of the CB2 receptors in mediating alcohol intake and ethanol-induced conditioned place preference (EtOH-CPP) and sensitivity in mice. The effect of BCP on alcohol intake was evaluated using the standard two-bottle choice drinking method. The mice were presented with increasing EtOH concentrations and its consumption was measured daily. Consumption of saccharin and quinine solutions was measured following the EtOH preference tests. Finally, the effect of BCP on alcohol reward and sensitivity was tested using an unbiased EtOH-CPP and loss of righting-reflex (LORR) procedures, respectively. BCP dose-dependently decreased alcohol consumption and preference. Additionally, BCP-injected mice did not show any difference from vehicle mice in total fluid intake in a 24-hour paradigm nor in their intake of graded concentrations of saccharin or quinine, suggesting that the CB2 receptor activation did not alter taste function. More importantly, BCP inhibited EtOH-CPP acquisition and exacerbated LORR duration. Interestingly, these effects were abrogated when mice were pre-injected with a selective CB2 receptor antagonist, AM630. Overall, the CB2 receptor system appears to be involved in alcohol dependence and sensitivity and may represent a potential pharmacological target for the treatment of alcoholism.

  1. The α3β4 nAChR partial agonist AT-1001 attenuates stress-induced reinstatement of nicotine seeking in a rat model of relapse and induces minimal withdrawal in dependent rats.

    PubMed

    Yuan, Menglu; Malagon, Ariana M; Yasuda, Dennis; Belluzzi, James D; Leslie, Frances M; Zaveri, Nurulain T

    2017-08-30

    The strong reinforcing effects of nicotine and the negative symptoms such as anxiety experienced during a quit attempt often lead to relapse and low success rates for smoking cessation. Treatments that not only block the reinforcing effects of nicotine but also attenuate the motivation to relapse are needed to improve cessation rates. Recent genetic and preclinical studies have highlighted the involvement of the α3, β4, and α5 nicotinic acetylcholine receptor (nAChR) subunits and the α3β4 nAChR subtype in nicotine dependence and withdrawal. However, the involvement of these nAChR in relapse is not fully understood. We previously reported that the α3β4 nAChR partial agonist AT-1001 selectively decreases nicotine self-administration in rats without affecting food responding. In the present experiments, we examined the efficacy of AT-1001 in attenuating reinstatement of nicotine-seeking behavior in a model of stress-induced relapse. Rats extinguished from nicotine self-administration were treated with the pharmacological stressor yohimbine prior to AT-1001 treatment and reinstatement testing. We also examined whether AT-1001 produced any withdrawal-related effects when administered to nicotine-dependent rats. We found that AT-1001 dose-dependently reduced yohimbine stress-induced reinstatement of nicotine seeking. When administered to nicotine-dependent rats at the dose that significantly blocked nicotine reinstatement, AT-1001 elicited minimal somatic withdrawal signs in comparison to the nicotinic antagonist mecamylamine, which is known to produce robust withdrawal. Our data suggest that α3β4 nAChR-targeted compounds may be a promising approach for nicotine addiction treatment because they can not only block nicotine's reinforcing effects, but also decrease motivation to relapse without producing significant withdrawal effects. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Blast traumatic brain injury induced cognitive deficits are attenuated by pre- or post-injury treatment with the glucagon-like peptide-1 receptor agonist, exendin-4

    PubMed Central

    Tweedie, David; Rachmany, Lital; Rubovitch, Vardit; Li, Yazhou; Holloway, Harold W.; Lehrmann, Elin; Zhang, Yongqing; Becker, Kevin G.; Perez, Evelyn; Hoffer, Barry J.; Pick, Chaim G.; Greig, Nigel H.

    2015-01-01

    Background Blast traumatic brain injury (B-TBI) affects military and civilian personnel. Presently there are no approved drugs for blast brain injury. Methods Exendin-4, administered subcutaneously, was evaluated as a pre-treatment (48 hours) and post-injury treatment (2 hours) on neurodegeneration, behaviors and gene expressions in a murine open field model of blast injury. Results B-TBI induced neurodegeneration, changes in cognition and genes expressions linked to dementia disorders. Exendin-4, administered pre- or post-injury ameliorated B-TBI-induced neurodegeneration at 72 hours, memory deficits from days 7–14 and attenuated genes regulated by blast at day 14 post-injury. Conclusions The present data suggest shared pathological processes between concussive and B-TBI, with endpoints amenable to beneficial therapeutic manipulation by exendin-4. B-TBI-induced dementia-related gene pathways and cognitive deficits in mice somewhat parallel epidemiological studies of Barnes and co-workers who identified a greater risk in US military veterans who experienced diverse TBIs, for dementia in later life. PMID:26327236

  3. Does combined peroxisome proliferator-activated receptors-agonist and pravastatin therapy attenuate the onset of diabetes-induced experimental nephropathy?

    PubMed

    Gad, Hayam I

    2014-11-01

    To investigate the combined effects of rosiglitazone and pravastatin on renal functions in early streptozotocin induced diabetic nephropathy (DN). This study was carried out at King Khalid University Hospital Animal House, Riyadh, Saudi Arabia from August 2013 to February 2014. Fifty male Wistar rats were assigned to normal control rats and diabetic rats that received saline, rosiglitazone, pravastatin, or rosiglitazone+pravastatin for 2 months. Their weight range was 230-250 gm, and age range was from 18-20 weeks. At the end of experiment, creatinine clearance, and urinary albumin to creatinine ratio (ACR) were measured. Blood samples were analyzed for transferrin, glycosylated hemoglobin (HbA1c), lipid profile, tumor necrosis factor-alpha (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and lipid peroxide. Rosiglitazone treatment increased creatinine clearance and plasma transferrin, and decreased urinary ACR, HbA1c, plasma TNF-α, ICAM-1, and serum lipid peroxide levels without affecting the altered lipid profile. Pravastatin treatment produced similar results and normalized the lipid alteration. The combination of rosiglitazone and pravastatin was more effective in attenuating the diabetes-induced nephropathy compared with treatment with either drug alone. The combination strategy of rosiglitazone and pravastatin may provide a potential synergistic renoprotective effect against DN by improving renal functions and reducing indices of DN. 

  4. Rosiglitazone, a PPAR-γ agonist, fails to attenuate CLA-induced milk fat depression and hepatic lipid accumulation in lactating mice.

    PubMed

    Vyas, Diwakar; Teter, Beverly B; Delmonte, Pierluigi; Erdman, Richard A

    2014-07-01

    Our objective was to investigate the combination of rosiglitazone (ROSI) and conjugated linoleic acid (CLA) on mammary and hepatic lipogenesis in lactating C57Bl/6 J mice. Twenty-four lactating mice were randomly assigned to one of four treatments applied from postpartum day 6 to day 10. Treatments included: (1) control diet, (2) control plus 1.5 % dietary CLA (CLA) substituted for soybean oil, (3) control plus daily intra-peritoneal (IP) rosiglitazone injections (10 mg/kg body weight) (ROSI), and (4) CLA plus ROSI (CLA-ROSI). Dam food intake and milk fat concentration were depressed with CLA. However, no effects were observed with ROSI. The CLA-induced milk fat depression was due to reduced expression for mammary lipogenic genes involved in de-novo fatty acid (FA) synthesis, FA uptake and desaturation, and triacyglycerol synthesis. Liver weight (g/100 g body weight) was increased by CLA due to an increase in lipid accumulation triggering a compensatory reduction in mRNA abundance of hepatic lipogenic enzymes, including acetyl-CoA carboxylase I and stearoyl-CoA desaturase I. On the contrary, no effects were observed with ROSI on hepatic and mammary lipogenic gene and enzyme expression. Overall, feeding CLA to lactating mice induced milk fat depression and increased hepatic lipid accumulation, probably due to the presence of trans-10, cis-12 CLA isomer, while ROSI failed to significantly attenuate both hepatic steatosis and reduction in milk fat content.

  5. Attenuating effect of lisinopril and telmisartan in intracerebroventricular streptozotocin induced experimental dementia of Alzheimer's disease type: possible involvement of PPAR-γ agonistic property.

    PubMed

    Singh, Birdavinder; Sharma, Bhupesh; Jaggi, Amteshwar S; Singh, Nirmal

    2013-06-01

    This study investigates the beneficial role of lisinopril, an angiotensin converting enzyme inhibitor (ACEI) and telmisartan, an angiotensin receptor blocker (ARB), in intracerebroventricular (i.c.v.) streptozotocin (STZ) induced dementia of Alzheimer's disease (AD) type in mice. This study also aimed to explore the role of PPAR-γ in lisinopril and telmisartan mediated effects in i.c.v. STZ mice. Donepezil served as the positive control in the study. Mice underwent i.c.v. injection of STZ. The Morris water maze (MWM) test was employed for assessment of learning and memory. Various biochemical estimations, namely brain acetylcholinesterase (AChE) activity, myeloperoxidase (MPO) activity, nitrite/nitrate and thiobarbituric acid reactive species (TBARS) levels and reduced glutathione (GSH) levels, were also performed. The study showed that i.c.v. STZ significantly impaired learning and memory of the animals along with a significant enhancement in brain AChE, MPO, TBARS, nitrite/nitrate levels and reduction in brain GSH levels. Treatments of lisinopril/telmisartan/donepezil significantly attenuated STZ induced behavioral and biochemical changes. Pre-treatment with bisphenol-A-diglycidyl ether (BADGE), a selective PPAR-γ antagonist, significantly abolished the beneficial effect of lisinopril/telmisartan in i.c.v. STZ treated animals. The results of this investigation document a potential role of PPAR-γ in the beneficial effects of lisinopril and telmisartan in i.c.v. STZ dementia of AD type.

  6. Decibel attenuation of pulsed electromagnetic field (PEMF) in blood and cortical bone determined experimentally and from the theory of ohmic losses.

    PubMed

    Zborowski, Maciej; Kligman, Boris; Midura, Ronald J; Wolfman, Alan; Patterson, Thomas E; Ibiwoye, Michael; Grabiner, Mark

    2006-06-01

    We studied the PEMF power attenuation in tissues representative of clinical applications (blood and cortical bone) to determine the amount of power available for PEMF purported biological effects. The experimental system consisted of a pair of nearly circular, parallel and coaxial coils separated by a distance of one coil diameter. The power attenuation was measured using a small search coil connected to a digital oscilloscope. The coils were powered by a voltage switch operating at two different frequencies (3.8 and 63 kHz) producing bursts of pulses (numbering 21 and 1619) and triggered at two different frequencies (1.5 and 15 Hz, respectively). The tissue samples were placed inside the coils so as to expose them to either transverse electric field (at the center of coils) or the transverse magnetic field (at the coil wire). The cylindrical coil geometry yielded closed-form expressions for power attenuation based on magnetic diffusion equation and ohmic losses due to bulk tissue magnetic permeability and electrical conductivity. The measured power attenuation at these PEMF frequencies of not more than one decibel (1 dB) was well explained by the theory for the 3.8 kHz but less so for the 63 kHz frequency PEMF. The results provide important insights regarding physical mechanism of weak PEMF power dissipation in tissues.

  7. Is calcaneal broadband ultrasound attenuation a valid index of dual-energy x-ray absorptiometry-derived bone mass in children?

    PubMed Central

    Hirsch, R.; Nogueira, R. C.; Beck, B. R.

    2016-01-01

    Objectives The aim of the current study was to assess whether calcaneal broadband ultrasound attenuation (BUA) can predict whole body and regional dual-energy x-ray absorptiometry (DXA)-derived bone mass in healthy, Australian children and adolescents at different stages of maturity. Methods A total of 389 boys and girls across a wide age range (four to 18 years) volunteered to participate. The estimated age of peak height velocity (APHV) was used to classify children into pre-, peri-, and post-APHV groups. BUA was measured at the non-dominant heel with quantitative ultrasonometry (QUS) (Lunar Achilles Insight, GE), while bone mineral density (BMD) and bone mineral content (BMC) were examined at the femoral neck, lumbar spine and whole body (DXA, XR-800, Norland). Associations between BUA and DXA-derived measures were examined with Pearson correlations and linear regression. Participants were additionally ranked in quartiles for QUS and DXA measures in order to determine agreement in rankings. Results For the whole sample, BUA predicted 29% of the study population variance in whole body BMC and BMD, 23% to 24% of the study population variance in lumbar spine BMC and BMD, and 21% to 24% of the variance in femoral neck BMC and BMD (p < 0.001). BUA predictions were strongest for the most mature participants (pre-APHV R2 = 0.03 to 0.19; peri-APHV R2 = 0.05 to 0.17; post-APHV R2 = 0.18 to 0.28) and marginally stronger for girls (R2 = 0.25-0.32, p < 0.001) than for boys (R2 = 0.21-0.27, p < 0.001). Agreement in quartile rankings between QUS and DXA measures of bone mass was generally poor (27.3% to 38.2%). Conclusion Calcaneal BUA has a weak to moderate relationship with DXA measurements of bone mass in children, and has a tendency to misclassify children on the basis of quartile rankings. Cite this article: B. K. Weeks, R. Hirsch, R. C. Nogueira, B. R. Beck. Is calcaneal broadband ultrasound attenuation a valid index of dual-energy x-ray absorptiometry-derived bone mass

  8. Changes in bone turnover following gonadotropin-releasing hormone (GnRH) agonist administration and estrogen treatment in cynomolgus monkeys: a short-term model for evaluation of antiresorptive therapy.

    PubMed

    Stroup, G B; Hoffman, S J; Vasko-Moser, J A; Lechowska, B A; Jenkins, E L; Dare, L C; Gowen, M

    2001-05-01

    In this study we determine the early time course of estrogen deficiency-induced bone loss in the cynomolgus monkey and examine the potential of this method for evaluating antiresorptive therapies. In two groups of animals, estrogen deficiency was induced by the administration of a gonadotropin-releasing hormone agonist (GnRHa) and bone turnover was measured using biochemical markers. Two weeks after receiving GnRHa, serum estradiol decreased to below the detection limit in most animals and remained there through 6 months or until estrogen replacement started (months 4-6). Relative to untreated animals, urinary deoxypyridinoline (dPyr), as well as C- and N-telopeptides of type I collagen, were significantly elevated 4 weeks after receiving GnRHa. Serum osteocalcin increased in GnRHa-treated animals as early as week 4 and the level was significantly higher than in untreated control animals from weeks 8-24. Estradiol treatment returned all measures of bone turnover to control levels within 2 weeks. The use of biochemical markers as surrogates of bone turnover and loss was validated by measurement of bone mineral density (BMD), which showed a significant reduction at 6 months in estrogen-deficient animals. However, lumbar BMD in animals that received GnRHa and estradiol was similar to that in animals that had not received GnRHa. In conclusion, a monthly depot injection of GnRHa resulted in increased bone turnover due to estrogen deficiency, as early as 4 weeks after treatment. Estrogen administration returned bone turnover to control levels in 2 weeks. This method represents a valid model for evaluating antiresorptive agents in the short term in a nonhuman primate. Furthermore, the data suggest that changes in biochemical markers in response to antiresorptive therapy in humans may be detectable at much earlier timepoints than commonly used.

  9. Genistein suppresses Prevotella intermedia lipopolysaccharide-induced inflammatory response in macrophages and attenuates alveolar bone loss in ligature-induced periodontitis.

    PubMed

    Choi, Eun-Young; Bae, Seung Han; Ha, Min Hee; Choe, So-Hui; Hyeon, Jin-Yi; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

    2016-02-01

    Genistein is a major isoflavone subclass of flavonoids found in soybean and a potent tyrosine kinase inhibitor. The present study aimed to assess the effect of genistein on the production of proinflammatory mediators in murine macrophages stimulated with lipopolysaccharide (LPS) isolated from Prevotella intermedia, a pathogen associated with different forms of periodontal disease, and to evaluate its possible influence on alveolar bone loss in ligature-induced periodontitis using micro-computed tomography (micro-CT) analysis as well. LPS was isolated from P. intermedia ATCC 25611 by using the standard hot phenol-water method. Culture supernatants were analyzed for nitric oxide (NO) and interleukin-6 (IL-6). Inducible NO synthase (iNOS) protein expression was evaluated by immunoblot analysis. Real-time PCR was carried out to measure iNOS and IL-6 mRNA expression. In addition, effect of genistein on alveolar bone loss was evaluated in a rat model of experimental periodontitis using micro-CT analysis. Genistein significantly attenuated P. intermedia LPS-induced production of iNOS-derived NO and IL-6 with attendant decrease in their mRNA expression in RAW264.7 cells. In addition, when genistein was administered to rats, decreases in alveolar bone height and bone volume fraction induced by ligature placement were significantly inhibited. Genistein administration also prevented ligature-induced alterations in the microstructural parameters of trabecular bone, including trabecular thickness, trabecular separation, bone mineral density and structure model index. While additional studies are required, we suggest that genistein could be utilized for the therapy of human periodontitis in the future. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The inhibitor of calcium/calmodulin-dependent protein kinase II KN93 attenuates bone cancer pain via inhibition of KIF17/NR2B trafficking in mice.

    PubMed

    Liu, Yue; Liang, Ying; Hou, Bailing; Liu, Ming; Yang, Xuli; Liu, Chenglong; Zhang, Juan; Zhang, Wei; Ma, Zhengliang; Gu, Xiaoping

    2014-09-01

    The N-methyl-d-aspartate receptor (NMDAR) containing subunit 2B (NR2B) is critical for the regulation of nociception in bone cancer pain, although the precise molecular mechanisms remain unclear. KIF17, a kinesin motor, plays a key role in the dendritic transport of NR2B. The up-regulation of NR2B and KIF17 transcription results from an increase in phosphorylated cAMP-response element-binding protein (CREB), which is activated by calcium/calmodulin-dependent protein kinase II (CaMKII). In this study, we hypothesized that CaMKII-mediated KIF17/NR2B trafficking may contribute to bone cancer pain. Osteosarcoma cells were implanted into the intramedullary space of the right femurs of C3H/HeJ mice to induce progressive bone cancer-related pain behaviors. The expression of spinal t-CaMKII, p-CaMKII, NR2B and KIF17 after inoculation was also evaluated. These results showed that inoculation of osteosarcoma cells induced progressive bone cancer pain and resulted in a significant up-regulation of p-CaMKII, NR2B and KIF17 expression after inoculation. Intrathecal administration of KN93, a CaMKII inhibitor, down-regulated these three proteins and attenuated bone cancer pain in a dose- and time-dependent manner. These findings indicated that CaMKII-mediated KIF17/NR2B trafficking may contribute to bone cancer pain, and inhibition of CaMKII may be a useful alternative or adjunct therapy for relieving cancer pain.

  11. Thalidomide attenuates the development and expression of antinociceptive tolerance to μ-opioid agonist morphine through l-arginine-iNOS and nitric oxide pathway.

    PubMed

    Khan, Muhammad Imran; Ostadhadi, Sattar; Mumtaz, Faiza; Momeny, Majid; Moghaddaskho, Farima; Hassanipour, Mahsa; Ejtemaei-Mehr, Shahram; Dehpour, Ahmad Reza

    2017-01-01

    Morphine is a μ-opioid analgesic drug which is used in the treatment and management of chronic pain. However, due to development of antinociceptive tolerance its clinical use is limited. Thalidomide is an old glutamic acid derivative which recently reemerged because of its potential to counteract a number of disorders including neurodegenerative disorders. The potential underlying mechanisms and effects of thalidomide on morphine-induced antinociceptive tolerance is still elusive. Hence, the present study was designed to explore the effect of thalidomide on the development and expression of morphine antinociceptive tolerance targeting l-arginine-nitric oxide (NO) pathway in mice and T98G human glioblastoma cell line. When thalidomide was administered in a dose of 17.5mg/kg before each dose of morphine chronically for 5days it prevented the development of antinociceptive tolerance. Also, a single dose of thalidomide 20mg/kg attenuated the expression phase of antinociceptive tolerance. The protective effect of thalidomide was augmented in development phase when co-administration with NOS inhibitors like L-NAME (non- selective NOS inhibitor; 2mg/kg) or aminoguanidine (selective inducible NOS inhibitor; 50mg/kg). Also, the reversal effect of thalidomide in expression phase was potentiated when concomitantly administrated with L-NAME (5mg/kg) or aminoguanidine (100mg/kg). Co-administration of ODQ (a guanylyl cyclase inhibitor) 10mg/kg in developmental phase or 20mg/kg in expression phase also progressively increased the pain threshold. In addition, thalidomide (20μM) also significantly inhibited the overexpression of iNOS gene induced by morphine (2.5μM) in T98G cell line. Hence, our findings suggest that thalidomide has protective effect both in the development and expression phases of morphine antinociceptive tolerance. It is also evident that this effect of thalidomide is induced by the inhibition of NOS enzyme predominantly iNOS. Copyright © 2016 Elsevier Masson

  12. Increased circulating estradiol in mice fed a high-fat diet does not attenuate ovariectomy-induced bone structural deterioration

    USDA-ARS?s Scientific Manuscript database

    Ovariectomy-induced estrogen deficiency increases adiposity and induces substantial bone loss by increasing osteoclast activity. This study investigated whether obesity induced by a high-fat diet alter circulating estradiol levels, mitigates or exacerbates bone structure deterioration, and changes m...

  13. High fat diet attenuates hyperglycemia, body composition changes, and bone loss in male streptozotocin-induced type 1 diabetic mice.

    PubMed

    Carvalho, Adriana Lelis; DeMambro, Victoria E; Guntur, Anyonya R; Le, Phuong; Nagano, Kenichi; Baron, Roland; de Paula, Francisco José Albuquerque; Motyl, Katherine J

    2017-06-20

    There is a growing and alarming prevalence of obesity and the metabolic syndrome in type I diabetic patients (T1DM), particularly in adolescence. In general, low bone mass, higher fracture risk, and increased marrow adipose tissue (MAT) are features of diabetic osteopathy in insulin-deficient subjects. On the other hand, type 2 diabetes (T2DM) is associated with normal or high bone mass, a greater risk of peripheral fractures, and no change in MAT. Therefore, we sought to determine the effect of weight gain on bone turnover in insulin-deficient mice. We evaluated the impact of a 6-week high-fat (HFD) rich in medium chain fatty acids or low-fat diet (LFD) on bone mass and MAT in a streptozotocin (STZ)-induced model using male C57BL/6J mice at 8 weeks of age. Dietary intervention was initiated after diabetes confirmation. At the endpoint, lower non-fasting glucose levels were observed in diabetic mice fed with high fat diet compared to diabetic mice fed the low fat diet (STZ-LFD). Compared to euglycemic controls, the STZ-LFD had marked polydipsia and polyphagia, as well as reduced lean mass, fat mass, and bone parameters. Interestingly, STZ-HFD mice had higher bone mass, namely less cortical bone loss and more trabecular bone than STZ-LFD. Thus, we found that a HFD, rich in medium chain fatty acids, protects against bone loss in a T1DM mouse model. Whether this may also translate to T1DM patients who are overweight or obese in respect to maintenance of bone mass remains to be determined through longitudinal studies. © 2017 Wiley Periodicals, Inc.

  14. Dried Plum Protects From Radiation-Induced Bone Loss by Attenuating Pro-Osteoclastic and Oxidative Stress Responses

    NASA Technical Reports Server (NTRS)

    Globus, Ruth

    2015-01-01

    Future space explorations beyond the earths magnetosphere will increase human exposure to space radiation and associated risks to skeletal health. We hypothesize that oxidative stress resulting from radiation exposure plays a major role in progressive bone loss and dysfunction in associated tissue. In animal studies, increased free radical formation is associated with pathological changes in bone structure, enhanced bone resorption, reduced bone formation and decreased bone mineral density, which can lead to skeletal fragility. Our long-term goals are to define the mechanisms and risk of bone loss in the spaceflight environment and to facilitate the development of effective countermeasures. We had previously reported that exposure to low or high-LET radiation correlates with an acute increase in the expression of pro-osteoclastic and oxidative stress genes in bone during the early response to radiation followed by pathological changes in skeletal structure. We then conducted systematic screening for potential countermeasures against bone loss where we tested the ability of various antioxidants to mitigate the radiation-induced increase in expression of these markers. For the screen, 16-week old C57Bl6J mice were treated with a dietary antioxidant cocktail, injectable DHLA or a dried plum-enriched diet (DP). Mice were then exposed to 2Gy 137Cs radiation and one day later, marrow cells were collected and the relevant genes analyzed for expression levels. Among the candidate countermeasures tested, DP was most effective in reducing the expression of genes associated with bone loss. Furthermore, analysis of skeletal structure by microcomputed tomography (microCT) revealed that DP also prevents the radiation-induced deterioration in skeletal microarchitecture as indicated by parameters such as percent bone volume (BVTV), trabecular spacing and trabecular number. We also found that DP has similar protective effects on skeletal structure in a follow-up study using 1 Gy of

  15. Attenuated Wnt/β-catenin signalling mediates methotrexate chemotherapy-induced bone loss and marrow adiposity in rats.

    PubMed

    Georgiou, Kristen R; King, Tristan J; Scherer, Michaela A; Zhou, Hong; Foster, Bruce K; Xian, Cory J

    2012-06-01

    Cancer chemotherapy often causes significant bone loss, marrow adiposity and haematopoietic defects, yet the underlying mechanisms and recovery potential remain unclear. Wnt/β-catenin signalling is integral to the regulation of osteogenesis, adipogenesis and haematopoiesis; using a rat model, the current study investigated roles of this signalling pathway in changes to bone marrow stromal and haematopoietic cell differentiation after chemotherapy with methotrexate (MTX), a commonly used antimetabolite. MTX treatment in rats (5 daily administrations at 0.75 mg/kg) has previously been found to decrease bone volume and increase marrow fat, which was associated with increased osteoclastogenesis in haematopoietic cells and with an osteogenesis to adipogenesis switch in bone marrow stromal cells of treated rats. In the current study, on day 6 after the first MTX dose we found that accompanying these changes as well as a suppressed haematopoietic cellularity but increased granulocyte/macrophage differentiation potential, there was an increase in mRNA expression of Wnt antagonists sFRP-1 and Dkk-1 in bone, a reduction in nuclear β-catenin protein in bone marrow stromal cells, and decreased mRNA levels of β-catenin target genes lef-1, cyclin D1 and survivin, suggesting reduced activation of Wnt/β-catenin signalling in the bone during MTX-induced damage. Concurrent administration of BIO, a GSK-3β inhibitor that stabilises β-catenin, partially abrogated the MTX-induced transient changes in osteogenic/adipogenic commitment, granulocyte/macrophage lineage differentiation and osteoclast number. These findings demonstrate a potentially important role of Wnt/β-catenin signalling in MTX chemotherapy-induced cellular changes to the bone marrow microenvironment.

  16. Isopsoralen-mediated suppression of bone marrow adiposity and attenuation of the adipogenic commitment of bone marrow-derived mesenchymal stem cells

    PubMed Central

    Wang, Jian; Li, Sheng-Fa; Wang, Ting; Sun, Chun-Han; Wang, Liang; Huang, Min-Jun; Chen, Jian; Zheng, Shao-Wei; Wang, Nan; Zhang, Ying-Jun; Chen, Tian-Yu

    2017-01-01

    Osteoporosis (OP) increases the risk of bone fractures and other complications, and is thus a major clinical problem. In this study, we examined the effect of isopsoralen on the differentiation of bone-derived marrow mesenchymal stem cells (BMSCs) into osteoblasts and adipocytes, as well as bone formation under osteoporotic conditions. Primary femoral BMSCs isolated from C57BL/6 mice were used to evaluate the isopsoralen-mediated regulation of the expression of alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) during osteogenesis 2 weeks. We also examined the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding protein β (C/EBPβ) under adipogenic conditions for 1 and 2 weeks. In addition, ovariectomized (OVX) mice were used to examine the effects of isopsoralen on bone formation for 2 months. Finally, mammalian target of rapamycin complex 1 (mTORC1) signaling was examined under osteogenic and adipogenic conditions. We found that following treatment with isopsoralen, the expression levels of ALP, OCN and RUNX2 were upregulated, whereas those of PPARγ and C/EBPβ were downregulated. mTORC1 signaling was also inhibited in vitro and in vivo. In the OVX mice that were intragastrically administered isopsoralen, bone parameters (trabecular thickness, bone volume/total volume and trabecular number) in the distal femoral metaphysis were significantly increased and the adipocyte number was decreased. On the whole, our findings demonstrate that isopsoralen promoted BMSC differentiation into osteoblasts and suppressed differentiation into adipocytes. PMID:28204811

  17. Isopsoralen-mediated suppression of bone marrow adiposity and attenuation of the adipogenic commitment of bone marrow-derived mesenchymal stem cells.

    PubMed

    Wang, Jian; Li, Sheng-Fa; Wang, Ting; Sun, Chun-Han; Wang, Liang; Huang, Min-Jun; Chen, Jian; Zheng, Shao-Wei; Wang, Nan; Zhang, Ying-Jun; Chen, Tian-Yu

    2017-03-01

    Osteoporosis (OP) increases the risk of bone fractures and other complications, and is thus a major clinical problem. In this study, we examined the effect of isopsoralen on the differentiation of bone-derived marrow mesenchymal stem cells (BMSCs) into osteoblasts and adipocytes, as well as bone formation under osteoporotic conditions. Primary femoral BMSCs isolated from C57BL/6 mice were used to evaluate the isopsoralen-mediated regulation of the expression of alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) during osteogenesis 2 weeks. We also examined the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding protein β (C/EBPβ) under adipogenic conditions for 1 and 2 weeks. In addition, ovariectomized (OVX) mice were used to examine the effects of isopsoralen on bone formation for 2 months. Finally, mammalian target of rapamycin complex 1 (mTORC1) signaling was examined under osteogenic and adipogenic conditions. We found that following treatment with isopsoralen, the expression levels of ALP, OCN and RUNX2 were upregulated, whereas those of PPARγ and C/EBPβ were downregulated. mTORC1 signaling was also inhibited in vitro and in vivo. In the OVX mice that were intragastrically administered isopsoralen, bone parameters (trabecular thickness, bone volume/total volume and trabecular number) in the distal femoral metaphysis were significantly increased and the adipocyte number was decreased. On the whole, our findings demonstrate that isopsoralen promoted BMSC differentiation into osteoblasts and suppressed differentiation into adipocytes.

  18. AdipoRon, an adiponectin receptor agonist, attenuates PDGF-induced VSMC proliferation through inhibition of mTOR signaling independent of AMPK: Implications toward suppression of neointimal hyperplasia.

    PubMed

    Fairaq, Arwa; Shawky, Noha M; Osman, Islam; Pichavaram, Prahalathan; Segar, Lakshman

    2017-02-22

    Hypoadiponectinemia is associated with an increased risk of coronary artery disease. Although adiponectin replenishment mitigates neointimal hyperplasia and atherosclerosis in mouse models, adiponectin therapy has been hampered in a clinical setting due to its large molecular size. Recent studies demonstrate that AdipoRon (a small-molecule adiponectin receptor agonist) improves glycemic control in type 2 diabetic mice and attenuates postischemic cardiac injury in adiponectin-deficient mice, in part, through activation of AMP-activated protein kinase (AMPK). To date, it remains unknown as to whether AdipoRon regulates vascular smooth muscle cell (VSMC) proliferation, which plays a major role in neointima formation. In the present study, oral administration of AdipoRon (50mg/kg) in C57BL/6J mice significantly diminished arterial injury-induced neointima formation by ∼57%. Under in vitro conditions, AdipoRon treatment led to significant inhibition of platelet-derived growth factor (PDGF)-induced VSMC proliferation, DNA synthesis, and cyclin D1 expression. While AdipoRon induced a rapid and sustained activation of AMPK, it also diminished basal and PDGF-induced phosphorylation of mTOR and its downstream targets, including p70S6K/S6 and 4E-BP1. However, siRNA-mediated AMPK downregulation showed persistent inhibition of p70S6K/S6 and 4E-BP1 phosphorylation, indicating AMPK-independent effects for AdipoRon inhibition of mTOR signaling. In addition, AdipoRon treatment resulted in a sustained and transient decrease in PDGF-induced phosphorylation of Akt and ERK, respectively. Furthermore, PDGF receptor-β tyrosine phosphorylation, which controls the phosphorylation state of Akt and ERK, was diminished upon AdipoRon treatment. Together, the present findings suggest that orally-administered AdipoRon has the potential to limit restenosis after angioplasty by targeting mTOR signaling independent of AMPK activation.

  19. Immune Response Modulation of Conjugated Agonists with Changing Linker Length.

    PubMed

    Ryu, Keun Ah; Slowinska, Katarzyna; Moore, Troy; Esser-Kahn, Aaron

    2016-12-16

    We report immune response modulation with linked Toll-like receptor (TLR) agonists. Conjugating two agonists of synergistic TLRs induce an increase in immune activity compared to equal molarity of soluble agonists. Additionally, varying the distance between the agonists by changing the linker length alters the level of macrophage NF-κB activity as well as primary bone marrow derived dendritic cell IL-6 production. This modulation is effected by the size of the agonists and the pairing of the stimulated TLRs. The sensitivity of linker-length-dependent immune activity of conjugated agonists provides the potential for developing application specific therapeutics.

  20. Inhibition of spinal UCHL1 attenuates pain facilitation in a cancer-induced bone pain model by inhibiting ubiquitin and glial activation

    PubMed Central

    Cheng, Wei; Chen, Yuan-Li; Wu, Liang; Miao, Bei; Yin, Qin; Wang, Jin-Feng; Fu, Zhi-Jian

    2016-01-01

    The present study examined alterations of spinal ubiquitin C-terminal hydrolase L1 (UCHL1), ubiquitin expression and glial activation in the cancer-induced bone pain rats. Furthermore, whether inhibition of spinal UCHL1 could alleviate cancer-induced bone pain was observed. The CIBP model was established by intrathecal Walker 256 mammary gland carcinoma cells in SD rats. The rats of CIBP developed significant pain facilitation in the Von Frey test. Double immunofluorescence analyses revealed that in the spines of CIBP rats, ubiquitin co-localized with NeuN, Iba-1 or GFAP; UCHL1 and NeuN were co-expressed and UCHL1 also co-localized with ubiquitin. The CIBP model induced up-regulation of ubiquitin and UCHL1 in the spines, as well as glial activation. Inhibition of spinal UCHL1 attenuated pain facilitation by down-regulation of ubiquitin expression and glial activation. in the CIBP rats. Our data suggests that UCHL1/ubiquitin distributed and increased in the spines of CIBP rats, that glial activation also increased in the CIBP model and that inhibition of spinal UCHL1 may be an effective method to alleviate cancer-induced bone pain. PMID:27508024

  1. Anti-Osteoclastic Activity of Artemisia capillaris Thunb. Extract Depends upon Attenuation of Osteoclast Differentiation and Bone Resorption-Associated Acidification Due to Chlorogenic Acid, Hyperoside, and Scoparone

    PubMed Central

    Lee, Sang-Hyun; Lee, Jung-Yun; Kwon, Young-In; Jang, Hae-Dong

    2017-01-01

    The present study attempts to elucidate the anti-osteoporotic activity of Artemisia capillaris Thunb. in the form of anti-osteoclastic effect and responsible bioactive compounds. The contents of chlorogenic acid, caffeic acid, hyperoside, isoquercitrin, isochlorogenic acid A, and scoparone in Artemisia capillaris hydroethanolic extract (ACHE) were 38.53, 0.52, 4.07, 3.03, 13.90, and 6.59 mg/g, respectively. ACHE diminished osteoclast differentiation and bone resorption due to chlorogenic acid, hyperoside, and scoparone. In addition, ACHE attenuated acidification as well as reducing tumor necrosis factor receptor-associated factor 6 (TRAF6) expression and its association with vacuolar H+-adenosine triphosphatase (V-ATPase). Furthermore, chlorogenic acid, hyperoside, and scoparone from A. capillaris abrogated the association of V-ATPase with TRAF6, suggesting that the blockage of bone resorption by A. capillaris was partially mediated by reducing acidification through down-regulating interaction of V-ATPase with TRAF6 due to scoparone as well as chlorogenic acid and hyperoside. These results imply that the anti-osteoclastic effect of A. capillaris through down-regulating osteoclast differentiation and bone resorption may contribute to its anti-osteoporotic effect. PMID:28165389

  2. Anti-Osteoclastic Activity of Artemisia capillaris Thunb. Extract Depends upon Attenuation of Osteoclast Differentiation and Bone Resorption-Associated Acidification Due to Chlorogenic Acid, Hyperoside, and Scoparone.

    PubMed

    Lee, Sang-Hyun; Lee, Jung-Yun; Kwon, Young-In; Jang, Hae-Dong

    2017-02-04

    The present study attempts to elucidate the anti-osteoporotic activity of Artemisia capillaris Thunb. in the form of anti-osteoclastic effect and responsible bioactive compounds. The contents of chlorogenic acid, caffeic acid, hyperoside, isoquercitrin, isochlorogenic acid A, and scoparone in Artemisia capillaris hydroethanolic extract (ACHE) were 38.53, 0.52, 4.07, 3.03, 13.90, and 6.59 mg/g, respectively. ACHE diminished osteoclast differentiation and bone resorption due to chlorogenic acid, hyperoside, and scoparone. In addition, ACHE attenuated acidification as well as reducing tumor necrosis factor receptor-associated factor 6 (TRAF6) expression and its association with vacuolar H⁺-adenosine triphosphatase (V-ATPase). Furthermore, chlorogenic acid, hyperoside, and scoparone from A. capillaris abrogated the association of V-ATPase with TRAF6, suggesting that the blockage of bone resorption by A. capillaris was partially mediated by reducing acidification through down-regulating interaction of V-ATPase with TRAF6 due to scoparone as well as chlorogenic acid and hyperoside. These results imply that the anti-osteoclastic effect of A. capillaris through down-regulating osteoclast differentiation and bone resorption may contribute to its anti-osteoporotic effect.

  3. Heme oxygenase-1 attenuates acute pulmonary inflammation by decreasing the release of segmented neutrophils from the bone marrow.

    PubMed

    Konrad, Franziska M; Braun, Stefan; Ngamsri, Kristian-Christos; Vollmer, Irene; Reutershan, Jörg

    2014-11-01

    Recruiting polymorphonuclear neutrophil granulocytes (PMNs) from circulation and bone marrow to the site of inflammation is one of the pivotal mechanisms of the innate immune system. During inflammation, the enzyme heme oxygenase 1 (HO-1) has been shown to reduce PMN migration. Although these effects have been described in various models, underlying mechanisms remain elusive. Recent studies revealed an influence of HO-1 on different cells of the bone marrow. We investigated the particular role of the bone marrow in terms of HO-1-dependent pulmonary inflammation. In a murine model of LPS inhalation, stimulation of HO-1 by cobalt (III) protoporphyrin-IX-chloride (CoPP) resulted in reduced segmented PMN migration into the alveolar space. In the CoPP group, segmented PMNs were also decreased intravascularly, and concordantly, mature and immature PMN populations were higher in the bone marrow. Inhibition of the enzyme by tin protoporphyrin-IX increased segmented and banded PMN migration into the bronchoalveolar lavage fluid with enhanced PMN release from the bone marrow and aggravated parameters of tissue inflammation. Oxidative burst activity was significantly higher in immature compared with mature PMNs. The chemokine stromal-derived factor-1 (SDF-1), which mediates homing of leukocytes into the bone marrow and is decreased in inflammation, was increased by CoPP. When SDF-1 was blocked by the specific antagonist AMD3100, HO-1 activation was no longer effective in curbing PMN trafficking to the inflamed lungs. In conclusion, we show evidence that the anti-inflammatory effects of HO-1 are largely mediated by inhibiting the release of segmented PMNs from the bone marrow rather than direct effects within the lung.

  4. A calcium-collagen chelate dietary supplement attenuates bone loss in postmenopausal women with osteopenia: a randomized controlled trial.

    PubMed

    Elam, Marcus L; Johnson, Sarah A; Hooshmand, Shirin; Feresin, Rafaela G; Payton, Mark E; Gu, Jennifer; Arjmandi, Bahram H

    2015-03-01

    Menopause leads to an increased risk for osteoporosis in women. Although drug therapies exist, increasing numbers of people prefer alternative therapies such as dietary supplements, for example, calcium, vitamin D, and collagen hydrolysates for the prevention and treatment of osteoporosis. We have previously shown that a 3-month intervention using a calcium-collagen chelate (CC) dietary supplement was efficacious in improving bone mineral density (BMD) and blood biomarkers of bone turnover in osteopenic postmenopausal women. This study reports the long-term efficacy of CC in reducing bone loss in postmenopausal women with osteopenia. Thirty-nine women were randomly assigned to one of two groups: 5 g of CC containing 500 mg of elemental calcium and 200 IU vitamin D (1,25-dihydroxyvitamin D3) or control (500 mg of calcium and 200 IU vitamin D) daily for 12 months. Total body, lumbar, and hip BMD were evaluated at baseline, 6 and 12 months using dual-energy X-ray absorptiometry. Blood was collected at baseline, 6 and 12 months to assess levels of blood biomarkers of bone turnover. Intent-to-treat (ITT) analysis was performed using repeated measures analysis of variance pairwise comparisons and multivariate analysis to assess time and group interactions. The loss of whole body BMD in women taking CC was substantially lower than that of the control group at 12 months in those who completed the study and the ITT analysis, respectively (CC: -1.33% and -0.33% vs. control: -3.75% and -2.17%; P=.026, P=.035). The CC group had significantly reduced levels of sclerostin and tartrate-resistant acid phosphatase isoform 5b (TRAP5b) (P<.05), and higher bone-specific alkaline phosphatase/TRAP5b ratio (P<.05) than control at 6 months. These results support the use of CC in reducing bone loss in osteopenic postmenopausal women.

  5. Dietary magnesium and potassium intakes and circulating magnesium are associated with heel bone ultrasound attenuation and osteoporotic fracture risk in the EPIC-Norfolk cohort study.

    PubMed

    Hayhoe, Richard P G; Lentjes, Marleen A H; Luben, Robert N; Khaw, Kay-Tee; Welch, Ailsa A

    2015-08-01

    In our aging population, maintenance of bone health is critical to reduce the risk of osteoporosis and potentially debilitating consequences of fractures in older individuals. Among modifiable lifestyle and dietary factors, dietary magnesium and potassium intakes are postulated to influence bone quality and osteoporosis, principally via calcium-dependent alteration of bone structure and turnover. We investigated the influence of dietary magnesium and potassium intakes, as well as circulating magnesium, on bone density status and fracture risk in an adult population in the United Kingdom. A random subset of 4000 individuals from the European Prospective Investigation into Cancer and Nutrition-Norfolk cohort of 25,639 men and women with baseline data was used for bone density cross-sectional analyses and combined with fracture cases (n = 1502) for fracture case-cohort longitudinal analyses (mean follow-up 13.4 y). Relevant biological, lifestyle, and dietary covariates were used in multivariate regression analyses to determine associations between dietary magnesium and potassium intakes and calcaneal broadband ultrasound attenuation (BUA), as well as in Prentice-weighted Cox regression to determine associated risk of fracture. Separate analyses, excluding dietary covariates, investigated associations of BUA and fractures with serum magnesium concentration. Statistically significant positive trends in calcaneal BUA for women (n = 1360) but not men (n = 968) were apparent across increasing quintiles of magnesium plus potassium (Mg+K) z score intake (P = 0.03) or potassium intake alone (P = 0.04). Reduced hip fracture risk in both men (n = 1958) and women (n = 2755) was evident for individuals in specific Mg+K z score intake quintiles compared with the lowest. Statistically significant trends in fracture risk in men across serum magnesium concentration groups were apparent for spine fractures (P = 0.02) and total hip, spine, and wrist fractures (P = 0.02). None of these

  6. Glycinol Enhances Osteogenic Differentiation and Attenuates the Effects of Aging on Bone Marrow-derived Mesenchymal Stem Cells

    USDA-ARS?s Scientific Manuscript database

    Osteoporosis is characterized by decreased bone mineral density and increased risk of fractures. It is most prevalent in the elderly population, leading to significant morbidity and mortality. Recently, phytoestrogens have gained significant attention as an alternative therapy due to their structura...

  7. Gremlin: vexing VEGF receptor agonist.

    PubMed

    Claesson-Welsh, Lena

    2010-11-04

    Gremlins are mischievous creatures in English folklore, believed to be the cause of otherwise unexplainable breakdowns (the word gremlins is derived from the Old English "gremian" or "gremman," "to vex"). Gremlin (or Gremlin-1) is also the designation of a secreted protein that is known to regulate bone formation during development. In this issue of Blood, Mitola et al report the novel role of Gremlin as a VEGFR2 agonist and the function of the Gremlin protein seems vexing indeed.

  8. Bone marrow mesenchymal stem cells attenuate 2,5-hexanedione-induced neuronal apoptosis through a NGF/AKT-dependent pathway.

    PubMed

    Wang, Qingshan; Sun, Guohua; Gao, Chenxue; Feng, Lina; Zhang, Yan; Hao, Jie; Zuo, Enjun; Zhang, Cong; Li, Shuangyue; Piao, Fengyuan

    2016-10-05

    Growing evidence suggests that the increased neuronal apoptosis is involved in n-hexane-induced neuropathy. We have recently reported that bone marrow-mesenchymal stem cells-derived conditioned medium (BMSC-CM) attenuated 2,5-hexanedione (HD, the active metabolite of n-hexane)-induced apoptosis in PC12 cells. Here, we explored the anti-apoptotic efficacy of BMSC in vivo. HD-treated rats received BMSC by tail vein injection 5 weeks after HD intoxication. We found that in grafted rats, BMSC significantly attenuated HD-induced neuronal apoptosis in the spinal cord, which was associated with elevation of nerve growth factor (NGF). Neutralization of NGF in BMSC-CM blocked the protection against HD-induced apoptosis in VSC4.1 cells, suggesting that NGF is essential for BMSC-afforded anti-apoptosis. Mechanistically, we found that the decreased activation of Akt induced by HD was significantly recovered in the spinal cord by BMSC and in VSC4.1 cells by BMSC-CM in a TrkA-dependent manner, leading to dissociation of Bad/Bcl-xL complex in mitochondria and release of anti-apoptotic Bcl-xL. The importance of Akt was further corroborated by showing the reduced anti-apoptotic potency of BMSC in HD-intoxicated VSC4.1 cells in the presence of Akt inhibitor, MK-2206. Thus, our findings show that BMSC attenuated HD-induced neuronal apoptosis in vivo through a NGF/Akt-dependent manner, providing a novel solution against n-hexane-induced neurotoxicity.

  9. Bone marrow mesenchymal stem cells attenuate 2,5-hexanedione-induced neuronal apoptosis through a NGF/AKT-dependent pathway

    PubMed Central

    Wang, Qingshan; Sun, Guohua; Gao, Chenxue; Feng, Lina; Zhang, Yan; Hao, Jie; Zuo, Enjun; Zhang, Cong; Li, Shuangyue; Piao, Fengyuan

    2016-01-01

    Growing evidence suggests that the increased neuronal apoptosis is involved in n-hexane-induced neuropathy. We have recently reported that bone marrow-mesenchymal stem cells-derived conditioned medium (BMSC-CM) attenuated 2,5-hexanedione (HD, the active metabolite of n-hexane)-induced apoptosis in PC12 cells. Here, we explored the anti-apoptotic efficacy of BMSC in vivo. HD-treated rats received BMSC by tail vein injection 5 weeks after HD intoxication. We found that in grafted rats, BMSC significantly attenuated HD-induced neuronal apoptosis in the spinal cord, which was associated with elevation of nerve growth factor (NGF). Neutralization of NGF in BMSC-CM blocked the protection against HD-induced apoptosis in VSC4.1 cells, suggesting that NGF is essential for BMSC-afforded anti-apoptosis. Mechanistically, we found that the decreased activation of Akt induced by HD was significantly recovered in the spinal cord by BMSC and in VSC4.1 cells by BMSC-CM in a TrkA-dependent manner, leading to dissociation of Bad/Bcl-xL complex in mitochondria and release of anti-apoptotic Bcl-xL. The importance of Akt was further corroborated by showing the reduced anti-apoptotic potency of BMSC in HD-intoxicated VSC4.1 cells in the presence of Akt inhibitor, MK-2206. Thus, our findings show that BMSC attenuated HD-induced neuronal apoptosis in vivo through a NGF/Akt-dependent manner, providing a novel solution against n-hexane-induced neurotoxicity. PMID:27703213

  10. Effects of pioglitazone and fenofibrate co-administration on bone biomechanics and histomorphometry in ovariectomized rats.

    PubMed

    Smith, Susan Y; Samadfam, Rana; Chouinard, Luc; Awori, Malaika; Bénardeau, Agnes; Bauss, Frieder; Guldberg, Robert E; Sebokova, Elena; Wright, Matthew B

    2015-11-01

    Pioglitazone, the peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonist is an effective therapy for type 2 diabetes, but has been associated with increased risk for bone fracture. Preclinical studies suggest that PPAR-α agonists (e.g., fenofibrate) increase bone mineral density/content, although clinical data on bone effects of fibrates are lacking. We investigated the effects of pioglitazone (10 mg/kg/day) and fenofibrate (25 mg/kg/day) on bone strength and bone histomorphometric parameters in osteopenic ovariectomized (OVX) rats. An additional group of rats received a combination of pioglitazone + fenofibrate to mimic the effects of a dual PPAR-α/γ agonist. The study consisted of a 13-week treatment phase followed by a 6-week treatment-free recovery period. Pioglitazone significantly reduced biomechanical strength at the lumbar spine and femoral neck compared with rats administered fenofibrate. Co-treatment with pioglitazone + fenofibrate had no significant effect on bone strength in comparison with OVX vehicle controls. Histomorphometric analysis of the proximal tibia revealed that pioglitazone suppressed bone formation and increased bone resorption at both cancellous and cortical bone sites relative to OVX vehicle controls. In contrast, fenofibrate did not affect bone resorption and only slightly suppressed bone formation. Discontinuation of pioglitazone treatment, both in the monotherapy and in the combination therapy arms, resulted in restoration of bone formation and resorption rates, demonstrating reversibility of effects. The above data support the concept that dual activation of PPAR-γ and PPAR-α attenuates the negative effects of PPAR-γ agonism on bone strength.

  11. The peroxisome proliferator-activated receptor γ agonist pioglitazone preserves bone microarchitecture in experimental arthritis by reducing the interleukin-17-dependent osteoclastogenic pathway.

    PubMed

    Koufany, Meriem; Chappard, Daniel; Netter, Patrick; Bastien, Claire; Weryha, Georges; Jouzeau, Jean-Yves; Moulin, David

    2013-12-01

    To investigate the effect of pioglitazone on inflammation-induced bone loss and changes in bone microarchitecture in rats with adjuvant-induced arthritis (AIA), focusing on the contribution of interleukin-17 (IL-17) and the balance of RANKL and osteoprotegerin (OPG). Male Lewis rats sensitized with Freund's complete adjuvant were treated orally for 21 days with 30 mg/kg/day of pioglitazone or vehicle. Arthritis severity was evaluated by clinical and histologic examination. Bone mineral density (BMD) was assessed by dual x-ray absorptiometry. The therapeutic effect of pioglitazone on changes of the bone architecture was determined by micro-computed tomography (micro-CT). Levels of RANKL, OPG, and IL-17 were determined by serum immunoassay and by synovial tissue immunohistochemistry. Messenger RNA for IL-17 and retinoic acid receptor-related orphan nuclear receptor γt (RORγt) was evaluated by quantitative reverse transcription-polymerase chain reaction and IL-17 promoter activity by gene-reporter assay. Micro-CT analysis revealed that pioglitazone treatment reduced arthritis severity and bone erosion scores and increased BMD in comparison to vehicle treatment. Cortical bone thickness was preserved, although the major beneficial effect of pioglitazone was on indices of the trabeculae, especially trabecular separation. Pioglitazone reduced the ratio of RANKL to OPG, in both the serum and the inflamed synovium. Circulating levels of IL-17 were significantly reduced by pioglitazone treatment, as were the percentages of IL-17-positive cells, mainly polymorphonuclear cells, in the inflamed synovium. Induction of IL-17 was strictly dependent on the binding of RORγt to IL-17 promoter, and lentiviral overexpression of peroxisome proliferator-activated receptor γ (PPARγ) reduced the expression of RORγt. Pioglitazone decreased the level of inflammatory bone destruction and protected the bone microarchitecture in rats with AIA by controlling the circulating and local

  12. Simultaneous screening for osteoporosis at CT colonography: bone mineral density assessment using MDCT attenuation techniques compared with the DXA reference standard.

    PubMed

    Pickhardt, Perry J; Lee, Lawrence J; del Rio, Alejandro Muñoz; Lauder, Travis; Bruce, Richard J; Summers, Ron M; Pooler, B Dustin; Binkley, Neil

    2011-09-01

    The purpose of this study was to evaluate the utility of lumbar spine attenuation measurement for bone mineral density (BMD) assessment at screening computed tomographic colonography (CTC) using central dual-energy X-ray absorptiometry (DXA) as the reference standard. Two-hundred and fifty-two adults (240 women and 12 men; mean age 58.9 years) underwent CTC screening and central DXA BMD measurement within 2 months (mean interval 25.0 days). The lowest DXA T-score between the spine and hip served as the reference standard, with low BMD defined per World Health Organization as osteoporosis (DXA T-score ≤ -2.5) or osteopenia (DXA T-score between -1.0 and -2.4). Both phantomless quantitative computed tomography (QCT) and simple nonangled region-of-interest (ROI) multi-detector CT (MDCT) attenuation measurements were applied to the T(12) -L(5) levels. The ability to predict osteoporosis and low BMD (osteoporosis or osteopenia) by DXA was assessed. A BMD cut-off of 90 mg/mL at phantomless QCT yielded 100% sensitivity for osteoporosis (29 of 29) and a specificity of 63.8% (143 of 224); 87.2% (96 of 110) below this threshold had low BMD and 49.6% (69 of 139) above this threshold had normal BMD at DXA. At L(1) , a trabecular ROI attenuation cut-off of 160 HU was 100% sensitive for osteoporosis (29 of 29), with a specificity of 46.4% (104 of 224); 83.9% (125 of 149) below this threshold had low BMD and 57.5% (59/103) above had normal BMD at DXA. ROI performance was similar at all individual T(12) -L(5) levels. At ROC analysis, AUC for osteoporosis was 0.888 for phantomless QCT [95% confidence interval (CI) 0.780-0.946] and ranged from 0.825 to 0.853 using trabecular ROIs at single lumbar levels (0.864; 95% CI 0.752-0.930 at multivariate analysis). Supine-prone reproducibility was better with the simple ROI method compared with QCT. It is concluded that both phantomless QCT and simple ROI attenuation measurements of the lumbar spine are effective for BMD screening at CTC

  13. Suppression of Wnt signaling by Dkk1 attenuates PTH-mediated stromal cell response and new bone formation

    PubMed Central

    Guo, Jun; Liu, Minlin; Yang, Dehong; Bouxsein, Mary L; Saito, Hiroaki; Galvin, R J Sells; Kuhstoss, Stuart A.; Thomas, Clare C; Schipani, Ernestina; Baron, Roland; Bringhurst, F Richard; Kronenberg, Henry M.

    2010-01-01

    SUMMARY Parathyroid hormone (PTH) suppresses Dickkopf 1 (Dkk1) expression in osteoblasts. To determine whether this suppression is essential for PTH-mediated Wnt signaling and bone formation, we examined mice that overexpress Dkk1 in osteoblasts (Dkk1 mice). Dkk1 mice were osteopenic due to abnormal osteoblast and osteoclast activity. When fed a low calcium diet, and in two other models of hyperparathyroidism, these mice failed to develop the peritrabecular stromal cell response (“osteitis fibrosis”) and new bone formation seen in wild type mice. Despite these effects of Dkk1 overexpression, PTH still activated Wnt signaling in Dkk1 mice and in osteoblastic cells cultured from these mice. In cultured MC3T3E1 preosteoblastic cells, PTH dramatically suppressed Dkk1 expression, induced PKA-mediated phosphorylation of β-catenin and significantly enhanced Lef1 expression. Our findings indicate that the full actions of PTH require intact Wnt signaling but that PTH can activate the Wnt pathway despite overexpression of Dkk1. PMID:20142103

  14. Suppression of Wnt signaling by Dkk1 attenuates PTH-mediated stromal cell response and new bone formation.

    PubMed

    Guo, Jun; Liu, Minlin; Yang, Dehong; Bouxsein, Mary L; Saito, Hiroaki; Galvin, R J Sells; Kuhstoss, Stuart A; Thomas, Clare C; Schipani, Ernestina; Baron, Roland; Bringhurst, F Richard; Kronenberg, Henry M

    2010-02-03

    Parathyroid hormone (PTH) suppresses Dickkopf 1 (Dkk1) expression in osteoblasts. To determine whether this suppression is essential for PTH-mediated Wnt signaling and bone formation, we examined mice that overexpress Dkk1 in osteoblasts (Dkk1 mice). Dkk1 mice were osteopenic due to abnormal osteoblast and osteoclast activity. When fed a low-calcium diet, and in two other models of hyperparathyroidism, these mice failed to develop the peritrabecular stromal cell response ("osteitis fibrosis") and new bone formation seen in wild-type mice. Despite these effects of Dkk1 overexpression, PTH still activated Wnt signaling in Dkk1 mice and in osteoblastic cells cultured from these mice. In cultured MC3T3E1 preosteoblastic cells, PTH dramatically suppressed Dkk1 expression, induced PKA-mediated phosphorylation of beta-catenin, and significantly enhanced Lef1 expression. Our findings indicate that the full actions of PTH require intact Wnt signaling but that PTH can activate the Wnt pathway despite overexpression of Dkk1.

  15. Evaluation of imaging technologies to correct for photon attenuation in the overlying tissue for in vivo bone strontium measurements

    NASA Astrophysics Data System (ADS)

    Heirwegh, C. M.; Chettle, D. R.; Pejović-Milić, A.

    2010-02-01

    The interpretation of measurements of bone strontium in vivo using energy dispersive x-ray fluorescence spectroscopy is presently hindered by overlying skin and soft-tissue absorption of the strontium x-rays. The use of imaging technologies to measure the overlying soft-tissue thickness at the index finger measuring site might allow correction of the strontium reading to estimate its concentration in bone. An examination of magnetic resonance (MR), computed tomography (CT) and high-frequency ultrasound (US) imaging technologies revealed that 55 MHz US had the smallest range of measurement uncertainty at 3.2% followed by 1 Tesla MR, 25 MHz US, 8 MHz US and CT at 4.3, 5.4, 6.6 and 7.1% uncertainty, respectively. Of these, only CT imaging appeared to underestimate total thickness (p < 0.05). Furthermore, an inter-study comparison on the accuracy of US measurements of the overlying tissue thickness at finger and ankle in nine subjects was investigated. The 8 MHz US system used in prior in vivo experiments was found to perform satisfactorily in a repeat study of ankle measurements, but indicated that finger thickness measurements may have been misread in previous studies by up to 17.7% (p < 0.025). Repeat ankle measurements were not significantly different from initial measurements at 2.2% difference.

  16. β-Glucans (Saccharomyces cereviseae) Reduce Glucose Levels and Attenuate Alveolar Bone Loss in Diabetic Rats with Periodontal Disease.

    PubMed

    Silva, Viviam de Oliveira; Lobato, Raquel Vieira; Andrade, Eric Francelino; de Macedo, Cristina Gomes; Napimoga, Juliana Trindade Clemente; Napimoga, Marcelo Henrique; Messora, Michel Reis; Murata, Ramiro Mendonça; Pereira, Luciano José

    2015-01-01

    The objective of this study was to assess the effects of oral ingestion of β-glucans isolated from Saccharomyces cereviseae on the metabolic profile, expression of gingival inflammatory markers and amount of alveolar bone loss in diabetic rats with periodontal disease. Diabetes mellitus was induced in 48 Wistar rats by intraperitoneal injection of streptozotocin (80 mg/kg). After confirming the diabetes diagnosis, the animals were treated with β-glucans (by gavage) for 28 days. On the 14th day of this period, periodontal disease was induced using a ligature protocol. β-glucans reduced the amount of alveolar bone loss in animals with periodontal disease in both the diabetic and non-diabetic groups (p < 0.05). β-glucans reduced blood glucose, cholesterol and triacylglycerol levels in diabetic animals, both with and without periodontal disease (p < 0.05). Furthermore, treatment with β-glucans reduced the expression of cyclooxygenase-2 and receptor activator of nuclear factor kappa-B ligand and increased osteoprotegerin expression in animals with diabetes and periodontal disease (p < 0.05). It was concluded that treatment with β-glucans has beneficial metabolic and periodontal effects in diabetic rats with periodontal disease.

  17. β-Glucans (Saccharomyces cereviseae) Reduce Glucose Levels and Attenuate Alveolar Bone Loss in Diabetic Rats with Periodontal Disease

    PubMed Central

    2015-01-01

    The objective of this study was to assess the effects of oral ingestion of β-glucans isolated from Saccharomyces cereviseae on the metabolic profile, expression of gingival inflammatory markers and amount of alveolar bone loss in diabetic rats with periodontal disease. Diabetes mellitus was induced in 48 Wistar rats by intraperitoneal injection of streptozotocin (80 mg/kg). After confirming the diabetes diagnosis, the animals were treated with β-glucans (by gavage) for 28 days. On the 14th day of this period, periodontal disease was induced using a ligature protocol. β-glucans reduced the amount of alveolar bone loss in animals with periodontal disease in both the diabetic and non-diabetic groups (p < 0.05). β-glucans reduced blood glucose, cholesterol and triacylglycerol levels in diabetic animals, both with and without periodontal disease (p < 0.05). Furthermore, treatment with β-glucans reduced the expression of cyclooxygenase-2 and receptor activator of nuclear factor kappa-B ligand and increased osteoprotegerin expression in animals with diabetes and periodontal disease (p < 0.05). It was concluded that treatment with β-glucans has beneficial metabolic and periodontal effects in diabetic rats with periodontal disease. PMID:26291983

  18. Mitochondrial calcium uniporter inhibition attenuates mouse bone marrow-derived mast cell degranulation induced by beta-1,3-glucan

    PubMed Central

    Cuong, Dang Van; Kim, Hyoung Kyu; Marquez, Jubert; Kim, Nari; Ko, Kyung Soo; Rhee, Byoung Doo

    2016-01-01

    Mast cells are primary mediators of allergic inflammation. Beta-1,3-glucan (BG) protects against infection and shock by activating immune cells. Activation of the BG receptor induces an increase in intracellular Ca2+, which may induce exocytosis. However, little is known about the precise mechanisms underlying BG activation of immune cells and the possible role of mitochondria in this process. The present study examined whether BG induced mast cell degranulation, and evaluated the role of calcium transients during mast cell activation. Our investigation focused on the role of the mitochondrial calcium uniporter (MCU) in BG-induced degranulation. Black mouse (C57) bone marrow-derived mast cells were stimulated with 0.5 µg/ml BG, 100 µg/ml peptidoglycan (PGN), or 10 µM A23187 (calcium ionophore), and dynamic changes in cytosolic and mitochondrial calcium and membrane potential were monitored. BG-induced mast cell degranulation occurred in a time-dependent manner, and was significantly reduced under calcium-free conditions. Ruthenium red, a mitochondrial Ca2+ uniporter blocker, significantly reduced mast cell degranulation induced by BG, PGN, and A23187. These results suggest that the mitochondrial Ca2+ uniporter has an important regulatory role in BG-induced mast cell degranulation. PMID:26937218

  19. Lymphocytes with Aberrant Expression of Fas or Fas-ligand Attenuate Immune Bone Marrow Failure in a Mouse Model

    PubMed Central

    Omokaro, Stephanie O.; Desierto, Marie J.; Eckhaus, Michael A.; Ellison, Felicia M.; Chen, Jichun; Young, Neal S.

    2012-01-01

    Bone marrow (BM) and lymphocyte samples from aplastic anemia patients show up-regulated Fas and Fas-ligand (FasL) expression respectively, supporting a relationship between immune-mediated BM destruction and the Fas apoptotic pathway. Mice with spontaneous lymphoproliferation (lpr) and generalized lymphoproliferative disease (gld) mutations exhibit abnormal expression of Fas and FasL; serving as potential models to elucidate underlying mechanisms of BM failure. We examined cellular and functional characteristics of lpr and gld mutants on the C57BL/6 (B6) background. Lymph node (LN) cells from lpr and gld mice produced less apoptosis when co-incubated with C.B10-H2b/LilMcd (C.B10) BM cells in vitro. This functional difference was confirmed by infusing lpr, gld, and B6 LN cells into sub-lethally irradiated CB10 mice; all donor LN cells showed significant T cell expansion and activation but only B6 LN cells caused severe BM destruction. Mice infused with gld LN cells developed mild to moderate BM failure, despite receiving FasL-deficient effectors, thus suggesting the existence of alternative pathways or incomplete penetrance of the mutation. Paradoxically, mice that received Fas-deficient lpr LN cells also had reduced BM failure, likely due to down-regulation of pro-apoptotic genes, an effect that can be overcome by higher doses of lpr LN cells. Our model demonstrates that abnormal Fas or FasL expression interferes with the development of pancytopenia and marrow hypoplasia, validating a major role for the Fas/FasL cytotoxic pathway in immune-mediated BM failure, although disruption of this pathway does not completely abolish marrow destruction. PMID:19265119

  20. Lymphocytes with aberrant expression of Fas or Fas ligand attenuate immune bone marrow failure in a mouse model.

    PubMed

    Omokaro, Stephanie O; Desierto, Marie J; Eckhaus, Michael A; Ellison, Felicia M; Chen, Jichun; Young, Neal S

    2009-03-15

    Bone marrow (BM) and lymphocyte samples from aplastic anemia patients show up-regulated Fas and Fas-ligand (FasL) expression, respectively, supporting a relationship between immune-mediated BM destruction and the Fas apoptotic pathway. Mice with spontaneous lymphoproliferation (lpr) and generalized lymphoproliferative disease (gld) mutations exhibit abnormal expression of Fas and FasL, serving as potential models to elucidate underlying mechanisms of BM failure. We examined cellular and functional characteristics of lpr and gld mutants on the C57BL/6 (B6) background. Lymph node (LN) cells from lpr and gld mice produced less apoptosis when coincubated with C.B10-H2(b)/LilMcd (C.B10) BM cells in vitro. This functional difference was confirmed by infusing lpr, gld, and B6 LN cells into sublethally irradiated CB10 mice. All donor LN cells showed significant T cell expansion and activation, but only B6 LN cells caused severe BM destruction. Mice infused with gld LN cells developed mild to moderate BM failure despite receiving FasL-deficient effectors, thus suggesting the existence of alternative pathways or incomplete penetrance of the mutation. Paradoxically, mice that received Fas-deficient lpr LN cells also had reduced BM failure, likely due to down-regulation of proapoptotic genes, an effect that can be overcome by higher doses of lpr LN cells. Our model demonstrates that abnormal Fas or FasL expression interferes with the development of pancytopenia and marrow hypoplasia, validating a major role for the Fas/FasL cytotoxic pathway in immune-mediated BM failure, although disruption of this pathway does not completely abolish marrow destruction.

  1. The Neutrophil Response Induced by an Agonist for Free Fatty Acid Receptor 2 (GPR43) Is Primed by Tumor Necrosis Factor Alpha and by Receptor Uncoupling from the Cytoskeleton but Attenuated by Tissue Recruitment

    PubMed Central

    Björkman, Lena; Mårtensson, Jonas; Winther, Malene; Gabl, Michael; Holdfeldt, André; Uhrbom, Martin; Bylund, Johan; Højgaard Hansen, Anders; Pandey, Sunil K.; Ulven, Trond; Forsman, Huamei

    2016-01-01

    Ligands with improved potency and selectivity for free fatty acid receptor 2 (FFA2R) have become available, and we here characterize the neutrophil responses induced by one such agonist (Cmp1) and one antagonist (CATPB). Cmp1 triggered an increase in the cytosolic concentration of Ca2+, and the neutrophils were then desensitized to Cmp1 and to acetate, a naturally occurring FFA2R agonist. The antagonist CATPB selectively inhibited responses induced by Cmp1 or acetate. The activated FFA2R induced superoxide anion secretion at a low level in naive blood neutrophils. This response was largely increased by tumor necrosis factor alpha (TNF-α) in a process associated with a recruitment of easily mobilizable granules, but neutrophils recruited to an aseptic inflammation in vivo were nonresponding. Superoxide production induced by Cmp1 was increased in latrunculin A-treated neutrophils, but no reactivation of desensitized FFA2R was induced by this drug, suggesting that the cytoskeleton is not directly involved in terminating the response. The functional and regulatory differences between the receptors that recognize short-chain fatty acids and formylated peptides, respectively, imply different roles of these receptors in the orchestration of inflammation and confirm the usefulness of a selective FFA2R agonist and antagonist as tools for the exploration of the precise role of the FFA2R. PMID:27503855

  2. β2 Agonists.

    PubMed

    Billington, Charlotte K; Penn, Raymond B; Hall, Ian P

    2017-01-01

    History suggests β agonists, the cognate ligand of the β2 adrenoceptor, have been used as bronchodilators for around 5,000 years, and β agonists remain today the frontline treatment for asthma and chronic obstructive pulmonary disease (COPD). The β agonists used clinically today are the products of significant expenditure and over 100 year's intensive research aimed at minimizing side effects and enhancing therapeutic usefulness. The respiratory physician now has a therapeutic toolbox of long acting β agonists to prophylactically manage bronchoconstriction, and short acting β agonists to relieve acute exacerbations. Despite constituting the cornerstone of asthma and COPD therapy, these drugs are not perfect; significant safety issues have led to a black box warning advising that long acting β agonists should not be used alone in patients with asthma. In addition there are a significant proportion of patients whose asthma remains uncontrolled. In this chapter we discuss the evolution of β agonist use and how the understanding of β agonist actions on their principal target tissue, airway smooth muscle, has led to greater understanding of how these drugs can be further modified and improved in the future. Research into the genetics of the β2 adrenoceptor will also be discussed, as will the implications of individual DNA profiles on the clinical outcomes of β agonist use (pharmacogenetics). Finally we comment on what the future may hold for the use of β agonists in respiratory disease.

  3. Retinoids Regulate Adipogenesis Involving the TGFβ/SMAD and Wnt/β-Catenin Pathways in Human Bone Marrow Mesenchymal Stem Cells.

    PubMed

    Cao, Jun; Ma, Yuhong; Yao, Weiqi; Zhang, Xiaoye; Wu, Dongcheng

    2017-04-15

    Retinoids may regulate cell differentiation as ligands of retinoic acid receptors (RARs) and/or retinoid X receptors (RXRs). We showed that RAR agonists promoted adipogenesis by upregulating the expression of CCAAT/enhancer-binding protein β (C/EBPβ) in the early stages, but blocked adipogenesis at a later stage in human bone marrow mesenchymal stem cells (hBMSCs). RXR agonists promoted adipogenesis at all time points in hBMSCs. The effect of RAR agonists was mediated mainly by the RARβ subtype. RAR agonists, in contrast to RXR agonists, significantly promoted the expression of RARβ. Knockdown of the RARβ gene via small hairpin RNA (shRNA) attenuated the inhibition of RAR agonists toward adipogenesis. Furthermore, we found that RAR agonists upregulated the transforming growth factor β (TGFβ)/SMAD pathway and Wnt/β-catenin pathway on adipogenesis in hBMSCs, and the stimulating effects were noticeably decreased with the RARβ gene knockdown. Both RAR agonists and RXR agonists inhibited adipogenesis and blocked the promoter activity of C/EBPβ and peroxisome proliferator-activated receptor γ (PPARγ) in SW872 cell. These results indicated the RAR agonists perform dual roles in adipogenesis in hBMSCs, and the TGFβ/SMAD pathway and Wnt/β-catenin pathway may involve the inhibitory effect of RAR agonists. RARβ is the main receptor subtype mediating the effect. The roles of RXR agonists in adipogenesis exhibited cell type-specific differences, and may be based on the integration of signals from different RXR dimers.

  4. APD668, a G protein-coupled receptor 119 agonist improves fat tolerance and attenuates fatty liver in high-trans fat diet induced steatohepatitis model in C57BL/6 mice.

    PubMed

    Bahirat, Umakant Ashok; Shenoy, Rekha Raghuveer; Goel, Rajan Naresh; Nemmani, Kumar V S

    2017-04-15

    G-protein coupled receptor 119 (GPR119) receptor is a rhodopsin-like, class A Gαs-coupled receptor, predominantly expressed in pancreatic islet cells and intestinal entero-endocrine cells. GPR119 has been emerged as a novel therapeutic target for the treatment of dyslipidemia in type 2 diabetes. In this study, we investigated the effect of APD668, a GPR119 agonist alone and in combination with linagliptin, a DPPIV inhibitor on oral fat tolerance test. Our findings demonstrate that APD668, a GPR119 agonist inhibits the intestinal triglyceride absorption after acute fat load in mice. Single dose administration of APD668 increases incretin secretion and enhances total PYY levels in presence of fat load in mice. We found that, the anti-dyslipidemic action of APD668 was reversed in presence of exendin-3 in oral fat tolerance test. In addition, our results showed that exendin-3 (9-39) failed to block the effect of APD668 on gastric emptying indicating that gastric emptying effects of APD668 are indeed mediated through GPR119 receptor dependent mechanism. Combined administration of APD668 and linagliptin significantly increased plasma active GLP-1 levels in-vivo and showed improvement in fat tolerance. However, APD668 failed to show anti-dyslipidemic activity in tyloxapol-induced hyperlipidemia in mice. Furthermore, we investigated the chronic effects of APD668 on hepatic steatosis in high trans-fat diet fed steatohepatitis model in mice. Oral administration of APD668 in HTF diet fed mice ameliorated hepatic endpoints such as plasma ALT, AST, liver weight and steatosis. These findings suggest that GPR119 agonists may represent a promising therapeutic strategy for the treatment of dyslipidemia and non-alcoholic steatohepatitis.

  5. (6aR)-11-amino-N-propyl-noraporphine, a new dopamine D2 and serotonin 5-HT1A dual agonist, elicits potent antiparkinsonian action and attenuates levodopa-induced dyskinesia in a 6-OHDA-lesioned rat model of Parkinson's disease.

    PubMed

    Zhao, Rui; Lu, Weijian; Fang, Xing; Guo, Lin; Yang, Zhi; Ye, Na; Zhao, Jiahao; Liu, Zhili; Jia, Jia; Zheng, Longtai; Zhao, Bin; Zhang, Ao; Zhen, Xuechu

    2014-09-01

    Parkinson's disease (PD) drug therapy remains a challenge. Dual modulation of dopamine and 5-HT receptors has emerged as a promising approach in anti-PD drug development. Taking advantage of the newly discovered aporphine analogue(s), (6aR)-11-amino-N-propyl-noraporphine (SOMCL-171), which exhibited dual D2/5-HT1A receptor agonistic activity, we studied the effects of the compound on levodopa-induced dyskinesia (LID) in a PD animal model. The results demonstrated that SOMCL-171 elicited a potent anti-PD effect in a 6-OHDA-lesioned rat model. Chronic use of SOMCL-171 reduced LID without compromising the antiparkinsonian efficacy. Furthermore, we found that the antidyskinesia effect of SOMCL-171 is associated with its 5-HT1A agonistic activity and the up-regulation of the striatal 5-HT1A receptor. The present data indicated that chronic SOMCL-171 alone produced potent antiparkinsonian effects with weak dyskinesia, compared with that of levodopa. In addition, chronic SOMCL-171 application attenuated the development of levodopa-induced LID at no expense to the antiparkinsonian efficacy. Taken together, our data suggested that dual modulation of D2/5-HT1A receptors may provide a novel approach for drug development in PD and LID.

  6. Intrathecal injection of the peptide myr-NR2B9c attenuates bone cancer pain via perturbing N-methyl-D-aspartate receptor-PSD-95 protein interactions in mice.

    PubMed

    Liu, Yue; Cui, Xinlong; Sun, Yu-E; Yang, Xuli; Ni, Kun; Zhou, Yu; Ma, Zhengliang; Gu, Xiaoping

    2014-06-01

    N-methyl-D-aspartate receptor (NMDARs)-dependent central sensitization plays an important role in cancer pain. Binding of NMDAR subunit 2B (NR2B) by postsynaptic density protein-95 (PSD-95) can couple NMDAR activity to intracellular enzymes, such as neuronal nitric oxide synthase (nNOS), facilitate downstream signaling pathways, and modulate NMDAR stability, contributing to synaptic plasticity. In this study, we investigated whether perturbing the specific interaction between spinal NR2B-containing NMDAR and PSD-95, using a peptide-mimetic strategy, could attenuate bone cancer-related pain behaviors. Osteosarcoma cells were implanted into the intramedullary space of the right femurs of C3H/HeJ mice to induce progressive bone cancer-related pain behaviors. Western blotting was applied to examine the expression of spinal phospho-Tyr1472 NR2B, nNOS, and PSD-95. We further investigated the effects of intrathecal injection of the mimetic peptide Myr-NR2B9c, which competitively disrupts the interaction between PSD-95 and NR2B, on nociceptive behaviors and on the upregulation of phospho-Tyr1472 NR2B, nNOS, and PSD-95 associated with bone cancer pain in the spinal cord. Inoculation of osteosarcoma cells induced progressive bone cancer pain and resulted in a significant upregulation of phospho-Tyr1472 NR2B, nNOS, and PSD-95. Intrathecal administration of Myr-NR2B9c attenuated bone cancer-evoked mechanical allodynia, thermal hyperalgesia, and reduced spinal phospho-Tyr1472 NR2B, nNOS, and PSD-95 expression. Intrathecal administration of Myr-NR2B9c reduced bone cancer pain. Internalization of spinal NR2B and dissociation NR2B-containing NMDARs activation from downstream nNOS signaling may contribute to the analgesic effects of Myr-NR2B9c. This approach may circumvent the negative consequences associated with blocking NMDARs, and may be a novel strategy for the treatment of bone cancer pain.

  7. Monocyte chemotactic protein-1 attenuates and high-fat diet exacerbates bone loss in mice with pulmonary metastasis of Lewis lung carcinoma

    USDA-ARS?s Scientific Manuscript database

    Bone can be adversely affected by obesity and cancer-associated complications including wasting. The objective of this study was to determine whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects found in male C57BL/6 mice with Lewis lung...

  8. Dietary Supplement Attenuates Radiation-Induced Osteoclastogenic and Oxidative Stress-Related Responses and Protects Adult Mice from Radiation-Induced Bone Loss

    NASA Technical Reports Server (NTRS)

    Globus, Ruth; Schreurs, Ann-Sofie; Tahimic, Candice; Shirazi-Fard, Yasaman; Alwood, Joshua; Shahnazari, Mohammed; Halloran, Bernard

    2015-01-01

    Our central hypothesis is that oxidative stress plays a key role in cell dysfunction and progressive bone loss caused by radiation exposure during spaceflight. In animal studies, excess free radical formation is associated with pathological changes in bone structure, enhanced bone resorption, reduced bone formation and decreased bone mineral density, which can lead to skeletal fragility. We previously reported that exposure to low or high-LET radiation rapidly increases expression levels of pro-osteoclastogenic and oxidative stress-related genes in bone and marrow, followed by pathological changes in skeletal structure. To screen various antioxidants for radioprotective effects on bone, 4 month old, male C57Bl6/J mice were treated with a dietary antioxidant cocktail, injectable alpha-lipoic acid, or a dried plum-enriched diet (DP). Mice were then exposed to 2Gy 137Cs total body radiation and one day later marrow cells were collected and the relevant genes analyzed for expression levels. Of the candidates tested, DP was most effective in reducing bone resorption-related gene expression. Microcomputed tomography revealed that DP also prevented the radiation-induced deterioration of skeletal microarchitecture, as indicated by percent bone volume, trabecular spacing and trabecular number. DP had similar protective effects on skeletal structure after sequential exposure to protons (0.5 Gy, 150MeV/n) and 56Fe 0.5Gy, 600 MeV/n). When cultured ex vivo under osteogenic conditions, bone marrow-derived cells from DP-fed animals exhibited increased colony numbers compared to control diet-fed animals. These findings suggest that DP exerted pro-osteogenic effects apart from previously identified anti-resorptive actions, which may contribute to radioprotection of skeletal tissue. In conclusion, a diet enriched in certain types of antioxidants and polyphenols such as DP may be useful as an intervention to protect tissues from degenerative effects of ionizing radiation.

  9. A single intraperitoneal injection of bovine fetuin-A attenuates bone resorption in a murine calvarial model of particle-induced osteolysis.

    PubMed

    Jablonski, Heidrun; Polan, Christina; Wedemeyer, Christian; Hilken, Gero; Schlepper, Rüdiger; Bachmann, Hagen Sjard; Grabellus, Florian; Dudda, Marcel; Jäger, Marcus; Kauther, Max Daniel

    2017-09-21

    Particle-induced osteolysis, which by definition is an aseptic inflammatory reaction to implant-derived wear debris eventually leading to local bone destruction, remains the major reason for long-term failure of orthopedic endoprostheses. Fetuin-A, a 66kDa glycoprotein with diverse functions, is found to be enriched in bone. Besides being an important inhibitor of ectopic calcification, it has been described to influence the production of mediators of inflammation. Furthermore, a regulatory role in bone metabolism has been assigned. In the present study, the influence of a single dose of bovine fetuin-A, intraperitoneally injected in mice subjected to particle-induced osteolysis of the calvaria, was analyzed. Twenty-eight male C57BL/6 mice, twelve weeks of age, were randomly divided into four groups. Groups 2 and 4 were subjected to ultra-high molecular weight polyethylene (UHMWPE) particles placed on their calvariae while groups 1 and 3 were sham-operated. Furthermore, groups 3 and 4 received a single intraperitoneal injection of 20mg bovine fetuin-A while groups 1 and 2 were treated with physiologic saline. After 14days calvarial bone was qualitatively and quantitatively assessed using microcomputed tomography (μCT) and histomorphometrical approaches. Application of fetuin-A led to a reduction of particle-induced osteolysis in terms of visible osteolytic lesions and eroded bone surface. The reduction of bone thickness and bone volume, as elicited by UHMWPE, was alleviated by fetuin-A. In conclusion, fetuin-A was found to exert an anti-resorptive effect on particle-induced osteolysis in-vivo. Thus, fetuin-A could play a potentially osteoprotective role in the treatment of bone metabolic disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. A two-year history of high bone loading physical activity attenuates ethnic differences in bone strength and geometry in pre-/early pubertal children from a low-middle income country.

    PubMed

    Meiring, Rebecca M; Avidon, Ingrid; Norris, Shane A; McVeigh, Joanne A

    2013-12-01

    We examined the interplay between ethnicity and weight-bearing physical activity on the content and volumetric properties of bone in a pre- to early pubertal South African Black and White population. Sixty six children [Black boys, 10.4 (1.4)yrs, n=15; Black girls, 10.1 (1.2)yrs, n=27; White boys, 10.1 (1.1)yrs, n=7; White girls, 9.6 (1.3)yrs, n=17] reported on all their physical activities over the past two years in an interviewer administered physical activity questionnaire (PAQ). All participants underwent a whole body and site-specific DXA scan and we also assessed bone structure and estimated bone strength with pQCT. Children were classified as being either high or low bone loaders based on the cohort's median peak bone strain score estimated from the PAQ. In the low bone loading group, Black children had greater femoral neck bone mineral content (BMC) (2.9 (0.08)g) than White children (2.4 (0.11)g; p=0.05). There were no ethnic differences in the high bone loaders for femoral neck BMC. At the cortical site, the Black low bone loaders had a greater radius area (97.3 (1.3) vs 88.8 (2.6)mm(2); p=0.05) and a greater tibia total area (475.5 (8.7) vs. 397.3 (14.0)mm(2); p=0.001) and strength (1633.7 (60.1) vs. 1271.8 (98.6)mm(3); p=0.04) compared to the White low bone loaders. These measures were not different between the Black low and high bone loaders or between the Black and White high bone loaders. In conclusion, the present study shows that there may be ethnic and physical activity associations in the bone health of Black and White pre-pubertal children and further prospective studies are required to determine the possible ethnic specific response to mechanical loading.

  11. Antagonizing miR-218-5p attenuates Wnt signaling and reduces metastatic bone disease of triple negative breast cancer cells

    PubMed Central

    Taipaleenmäki, Hanna; Farina, Nicholas H.; van Wijnen, Andre J.; Stein, Janet L.

    2016-01-01

    Wnt signaling is implicated in bone formation and activated in breast cancer cells promoting primary and metastatic tumor growth. A compelling question is whether osteogenic miRNAs that increase Wnt activity for bone formation are aberrantly expressed in breast tumor cells to support metastatic bone disease. Here we report that miR-218-5p is highly expressed in bone metastases from breast cancer patients, but is not detected in normal mammary epithelial cells. Furthermore, inhibition of miR-218-5p impaired the growth of bone metastatic MDA-MB-231 cells in the bone microenvironment in vivo. These findings indicate a positive role for miR-218-5p in bone metastasis. Bioinformatic and biochemical analyses revealed a positive correlation between aberrant miR-218-5p expression and activation of Wnt signaling in breast cancer cells. Mechanistically, miR-218-5p targets the Wnt inhibitors Sclerostin (SOST) and sFRP-2, which highly enhances Wnt signaling. In contrast, delivery of antimiR-218-5p decreased Wnt activity and the expression of metastasis-related genes, including bone sialoprotein (BSP/IBSP), osteopontin (OPN/SPP1) and CXCR-4, implicating a Wnt/miR-218-5p regulatory network in bone metastatic breast cancer. Furthermore, miR-218-5p also mediates the Wnt-dependent up-regulation of PTHrP, a key cytokine promoting cancer-induced osteolysis. Antagonizing miR-218-5p reduced the expression of PTHrP and Rankl, inhibited osteoclast differentiation in vitro and in vivo, and prevented the development of osteolytic lesions in a preclinical metastasis model. We conclude that pathological elevation of miR-218-5p in breast cancer cells activates Wnt signaling to enhance metastatic properties of breast cancer cells and cancer-induced osteolytic disease, suggesting that miR-218-5p could be an attractive therapeutic target for preventing disease progression. PMID:27738322

  12. Consumption of onion juice modulates oxidative stress and attenuates the risk of bone disorders in middle-aged and post-menopausal healthy subjects.

    PubMed

    Law, Yat-Yin; Chiu, Hui-Fang; Lee, Hui-Hsin; Shen, You-Cheng; Venkatakrishnan, Kamesh; Wang, Chin-Kun

    2016-02-01

    Osteoporosis is a chronic inflammatory condition that is characterized by the loss of bone mineral density (BMD). The current study was undertaken to evaluate the impact of onion juice intake on the bone mineral density (BMD) and bone loss in corroboration with antioxidant effects in human (in vivo) as well as inhibitory effects on the differentiation of osteoclasts in the cell line (in vitro). For in vitro studies, the RAW 264.7 (osteoclast progenitor) cells were used to examine the anti-osteoclastogenic effect of onion. In the case of in vivo studies, twenty-four subjects were divided into two groups and advised to intake 100 mL of onion juice or placebo for 8 weeks. Anthropometric measurements and blood samples were collected at the initial, 2(nd), 6(th), 8(th) and 10(th) week. The result of in vitro studies indicated that onion extract would effectively inhibit the osteoclastogenesis and its differentiation. Significant changes in the levels of alkaline phosphatase (ALP), free radicals, total antioxidant capacity (TEAC) and various antioxidants were observed in onion administered subjects. The BMD of three postmenopausal women was also found to be mildly improved on supplementation with onion juice. Onion juice consumption showed a positive modulatory effect on the bone loss and BMD by improving antioxidant activities and thus can be recommended for treating various bone-related disorders, especially osteoporosis.

  13. Neuroprotective effects mediated by dopamine receptor agonists against malonate-induced lesion in the rat striatum.

    PubMed

    Fancellu, R; Armentero, M-T; Nappi, G; Blandini, F

    2003-10-01

    In rats, intrastriatal injection of malonate, a reversible inhibitor of the mitochondrial enzyme succinate dehydrogenase, induces a lesion similar to that observed following focal ischemia or in Huntington's disease. In this study we used the malonate model to explore the neuroprotective potential of dopamine agonists. Rats were injected intraperitoneally with increasing concentrations of D1, D2, or mixed D1/D2 dopamine agonists prior to intrastriatal injection of malonate. Administration of increasing doses of the D2-specific agonist quinpirole resulted in increased protection against malonate toxicity. Conversely, the D1-specific agonist SKF-38393, as well as the mixed D1/D2 agonist apomorphine, conferred higher neuroprotection at lower than at higher drug concentrations. Our data suggest that malonate- induced striatal toxicity can be attenuated by systemic administration of dopamine agonists, with D1 and D2 agonists showing different profiles of efficacy.

  14. [Melatonin receptor agonist].

    PubMed

    Uchiyama, Makoto

    2015-06-01

    Melatonin is a hormone secreted by the pineal gland and is involved in the regulation of human sleep-wake cycle and circadian rhythms. The melatonin MT1 and MT2 receptors located in the suprachiasmatic nucleus in the hypothalamus play a pivotal role in the sleep-wake regulation. Based on the fact that MT1 receptors are involved in human sleep onset process, melatonin receptor agonists have been developed to treat insomnia. In this article, we first reviewed functions of melatonin receptors with special reference to MT1 and MT2, and properties and clinical application of melatonin receptor agonists as hypnotics.

  15. Celastrol attenuates bone erosion in collagen-Induced arthritis mice and inhibits osteoclast differentiation and function in RANKL-induced RAW264.7.

    PubMed

    Gan, Ke; Xu, Lingxiao; Feng, Xiaoke; Zhang, Qiande; Wang, Fang; Zhang, Miaojia; Tan, Wenfeng

    2015-02-01

    Recently, the traditional Chinese medicine Tripterygium wilfordii Hook f (TwHF) of the Celastraceae family has attracted increasing attention for its potential therapeutic application in patients with rheumatoid arthritis (RA). It is well accepted that TwHF exerts the antirheumatic activity and mainly depends on its potent anti-inflammatory property. To further explore the therapeutic potential of the well-defined TwHF-derived single compound - celastrol in RA, we study the therapeutic efficacy of celastrol on bone erosion in collagen-induced arthritis (CIA) mice and delineate its effects on osteoclast differentiation and functions in RANKL-induced osteoclast precursors RAW264.7 cell line. In CIA mice, daily injection of celastrol (beginning on day 28 after arthritis induction) markedly suppressed arthritis, and reduced bone damage in the joints as demonstrated by histology and bone micro-computed tomography (CT). The effects were accompanied by reductions of osteoclast cells in joints, serum tartrate-resistant acid phosphatase (TRAP) 5b, and expression of osteoclastic genes (Trap, Ctsk, Ctr, Mmp-9) and transcriptional factors (c-Fos, c-Jun and NFATc1). When RAW264.7 cells were treated with RANKL, celastrol inhibited the formation of TRAP+ multinucleated cells and the bone-resorbing activity in dose-dependent manners. Furthermore, celastrol reduced the RANKL-induced expression of osteoclastic genes and transcriptional factors, as well as phosphorylation of NF-kB and mitogen-activated protein kinases (MAPK). These findings show that celastrol could directly inhibit osteoclast formation and function, suggesting a novel therapeutic strategy of celastrol for managing RA, especially in preventing bone destruction.

  16. Investigational melatonin receptor agonists.

    PubMed

    Hardeland, Rüdiger

    2010-06-01

    Melatonin is a major chronobiological regulator involved in circadian phasing, sleep, and numerous other functions including cyto-/neuroprotection, immune modulation, and energy metabolism. The suitability of melatonin as a drug is limited because of its short half-life. Therefore, various indolic and non-indolic melatonergic agonists have been developed. Frequent health problems such as sleep disturbances, neuropsychiatric disorders related to circadian dysphasing, and metabolic diseases associated with insulin resistance are targeted by melatonergic agonists. Various synthetic melatonergic drugs are compared with regard to receptor affinities, selectivity, effects on sleep, endogenous melatonin, circadian phase and insulin-related metabolism. The chemical design of melatonin receptor agonists is discussed in relation to consequences for receptor affinity, selectivity, metabolism, and spectrum of effects. Melatonergic agonists are suitable for phase-shifting circadian rhythms, and may be used for treating disorders related to circadian dysfunction including sleep difficulties. Facilitation of sleep onset is a general property, whereas promotion of sleep maintenance is demonstrable but not always fully sufficient. Details are especially available for tasimelteon. Support of insulin sensitivity may become a new area of application for compounds such as NEU-P11. Some drugs acting additionally as serotonergic antagonists display antidepressant properties.

  17. Different skeletal effects of the peroxisome proliferator activated receptor (PPAR)alpha agonist fenofibrate and the PPARgamma agonist pioglitazone.

    PubMed

    Syversen, Unni; Stunes, Astrid K; Gustafsson, Björn I; Obrant, Karl J; Nordsletten, Lars; Berge, Rolf; Thommesen, Liv; Reseland, Janne E

    2009-03-30

    All the peroxisome proliferator activated receptors (PPARs) are found to be expressed in bone cells. The PPARgamma agonist rosiglitazone has been shown to decrease bone mass in mice and thiazolidinediones (TZDs) have recently been found to increase bone loss and fracture risk in humans treated for type 2 diabetes mellitus. The aim of the study was to examine the effect of the PPARalpha agonist fenofibrate (FENO) and the PPARgamma agonist pioglitazone (PIO) on bone in intact female rats. Rats were given methylcellulose (vehicle), fenofibrate or pioglitazone (35 mg/kg body weight/day) by gavage for 4 months. BMC, BMD, and body composition were measured by DXA. Histomorphometry and biomechanical testing of excised femurs were performed. Effects of the compounds on bone cells were studied. The FENO group had higher femoral BMD and smaller medullary area at the distal femur; while trabecular bone volume was similar to controls. Whole body BMD, BMC, and trabecular bone volume were lower, while medullary area was increased in PIO rats compared to controls. Ultimate bending moment and energy absorption of the femoral shafts were reduced in the PIO group, while similar to controls in the FENO group. Plasma osteocalcin was higher in the FENO group than in the other groups. FENO stimulated proliferation and differentiation of, and OPG release from, the preosteoblast cell line MC3T3-E1. We show opposite skeletal effects of PPARalpha and gamma agonists in intact female rats. FENO resulted in significantly higher femoral BMD and lower medullary area, while PIO induced bone loss and impairment of the mechanical strength. This represents a novel effect of PPARalpha activation.

  18. Different skeletal effects of the peroxisome proliferator activated receptor (PPAR)α agonist fenofibrate and the PPARγ agonist pioglitazone

    PubMed Central

    Syversen, Unni; Stunes, Astrid K; Gustafsson, Björn I; Obrant, Karl J; Nordsletten, Lars; Berge, Rolf; Thommesen, Liv; Reseland, Janne E

    2009-01-01

    Background All the peroxisome proliferator activated receptors (PPARs) are found to be expressed in bone cells. The PPARγ agonist rosiglitazone has been shown to decrease bone mass in mice and thiazolidinediones (TZDs) have recently been found to increase bone loss and fracture risk in humans treated for type 2 diabetes mellitus. The aim of the study was to examine the effect of the PPARα agonist fenofibrate (FENO) and the PPARγ agonist pioglitazone (PIO) on bone in intact female rats. Methods Rats were given methylcellulose (vehicle), fenofibrate or pioglitazone (35 mg/kg body weight/day) by gavage for 4 months. BMC, BMD, and body composition were measured by DXA. Histomorphometry and biomechanical testing of excised femurs were performed. Effects of the compounds on bone cells were studied. Results The FENO group had higher femoral BMD and smaller medullary area at the distal femur; while trabecular bone volume was similar to controls. Whole body BMD, BMC, and trabecular bone volume were lower, while medullary area was increased in PIO rats compared to controls. Ultimate bending moment and energy absorption of the femoral shafts were reduced in the PIO group, while similar to controls in the FENO group. Plasma osteocalcin was higher in the FENO group than in the other groups. FENO stimulated proliferation and differentiation of, and OPG release from, the preosteoblast cell line MC3T3-E1. Conclusion We show opposite skeletal effects of PPARα and γ agonists in intact female rats. FENO resulted in significantly higher femoral BMD and lower medullary area, while PIO induced bone loss and impairment of the mechanical strength. This represents a novel effect of PPARα activation. PMID:19331671

  19. A diet high in protein, dairy, and calcium attenuates bone loss over twelve months of weight loss and maintenance relative to a conventional high-carbohydrate diet in adults.

    PubMed

    Thorpe, Matthew P; Jacobson, Edward H; Layman, Donald K; He, Xuming; Kris-Etherton, Penny M; Evans, Ellen M

    2008-06-01

    Weight loss causes bone mineral loss. Higher protein diets continue to be criticized for further potential harmful bone effects, including elevated urinary calcium, but may promote bone health if protein sources include dairy. Overweight middle-aged subjects (n = 130, 59 males) were randomized to a diet providing 1.4 g.kg(-1).d(-1) protein and 3 daily servings of dairy (PRO) or 0.8 g.kg(-1).d(-1) protein and 2 daily servings of dairy (CARB) for 4 mo of weight loss plus 8 mo of weight maintenance. Diets prescribed 6276 kJ/d for females and 7113 kJ/d for males. Bone mineral content and density (BMD) for whole body (WB), lumbar spine (LS) and total hip (TH) were measured using dual X-ray absorptiometry, and dietary intake using 3-d weighed food records. Urinary calcium was measured using 24-h collection at 0 and 8 mo for a subsample (n = 42). Participants lost body weight (mean, 95% CI) of 8.2% (7.5-8.9%) at 4 mo, 10.6% (9.5-11.8%) at 8 mo, and 10.5% (8.9-12.0%) at 12 mo without differences between groups at any time (P = 0.64). At 12 mo, PRO BMD was higher by 1.6% (0.3-3.0%) at WB, 2.1% (0.6-3.7%) at LS, and 1.4% (0.2-2.5%) at TH compared with CARB. PRO calcium intake was higher (PRO: 1140 +/- 58 mg/d, CARB: 766 +/- 46; P < 0.01), as was urinary calcium (PRO: 163 +/- 15 mg/d, CARB: 100 +/- 9.2; P < 0.01). A reduced-energy diet supplying 1.4 g.kg(-1).d(-1) protein and 3 dairy servings increased urinary calcium excretion but provided improved calcium intake and attenuated bone loss over 4 mo of weight loss and 8 additional mo of weight maintenance.

  20. Bone graft

    MedlinePlus

    Autograft - bone; Allograft - bone; Fracture - bone graft; Surgery - bone graft; Autologous bone graft ... Fuse joints to prevent movement Repair broken bones (fractures) that have bone loss Repair injured bone that ...

  1. Synthetic RORγ agonists regulate multiple pathways to enhance antitumor immunity

    PubMed Central

    Hu, Xiao; Liu, Xikui; Moisan, Jacques; Wang, Yahong; Lesch, Charles A.; Spooner, Chauncey; Morgan, Rodney W.; Zawidzka, Elizabeth M.; Mertz, David; Bousley, Dick; Majchrzak, Kinga; Kryczek, Ilona; Taylor, Clarke; Van Huis, Chad; Skalitzky, Don; Hurd, Alexander; Aicher, Thomas D.; Toogood, Peter L.; Glick, Gary D.; Paulos, Chrystal M.; Zou, Weiping; Carter, Laura L.

    2016-01-01

    ABSTRACT RORγt is the key transcription factor controlling the development and function of CD4+ Th17 and CD8+ Tc17 cells. Across a range of human tumors, about 15% of the CD4+ T cell fraction in tumor-infiltrating lymphocytes are RORγ+ cells. To evaluate the role of RORγ in antitumor immunity, we have identified synthetic, small molecule agonists that selectively activate RORγ to a greater extent than the endogenous agonist desmosterol. These RORγ agonists enhance effector function of Type 17 cells by increasing the production of cytokines/chemokines such as IL-17A and GM-CSF, augmenting expression of co-stimulatory receptors like CD137, CD226, and improving survival and cytotoxic activity. RORγ agonists also attenuate immunosuppressive mechanisms by curtailing Treg formation, diminishing CD39 and CD73 expression, and decreasing levels of co-inhibitory receptors including PD-1 and TIGIT on tumor-reactive lymphocytes. The effects of RORγ agonists were not observed in RORγ−/− T cells, underscoring the selective on-target activity of the compounds. In vitro treatment of tumor-specific T cells with RORγ agonists, followed by adoptive transfer to tumor-bearing mice is highly effective at controlling tumor growth while improving T cell survival and maintaining enhanced IL-17A and reduced PD-1 in vivo. The in vitro effects of RORγ agonists translate into single agent, immune system-dependent, antitumor efficacy when compounds are administered orally in syngeneic tumor models. RORγ agonists integrate multiple antitumor mechanisms into a single therapeutic that both increases immune activation and decreases immune suppression resulting in robust inhibition of tumor growth. Thus, RORγ agonists represent a novel immunotherapy approach for cancer. PMID:28123897

  2. The PPARα Agonist Fenofibrate Improves the Musculoskeletal Effects of Exercise in Ovariectomized Rats.

    PubMed

    Mosti, Mats Peder; Ericsson, Madelene; Erben, Reinhold G; Schüler, Christiane; Syversen, Unni; Stunes, Astrid Kamilla

    2016-10-01

    The musculoskeletal effects of exercise are attenuated by estrogen deficiency. The peroxisome proliferator-activated receptor-α agonist fenofibrate exerts beneficial effects in bone and muscle. We therefore examined whether fenofibrate could enhance the musculoskeletal training response during estrogen deficiency. We investigated the combined effects of 8 weeks of fenofibrate and jumping exercise in ovariectomized (OVX) Sprague Dawley rats. Female rats were allocated to a sham-operated group and four OVX groups; fenofibrate (OVX-Fen), exercise (OVX-Ex), combined fenofibrate and exercise (OVX-FenEx), and a control group (OVX-Ctr) (n = 12/group). Fenofibrate (90 mg/kg/d) or methylcellulose was given by gavage. The combination of exercise and fenofibrate resulted in enhanced femoral bone mineral density (BMD) and improved bone microarchitecture compared with fenofibrate alone as well as increased trabecular BMD compared with OVX-Ctr. These effects were not seen in the OVX-Ex group. Femoral BMD was normalized in both exercise groups relative to sham and increased more in all intervention groups compared with OVX-Ctr. A higher plasma level of the bone formation marker type 1 collagen amino propeptide was observed in the OVX-Fen and OVX-FenEx groups compared with controls. Lean mass and soleus muscle weight were higher in the OVX-FenEx group than in the OVX-Ctr group, which coincided with lower mRNA levels of Atrogin1. These results suggest that peroxisome proliferator-activated receptor-α activation improves the musculoskeletal effects of exercise during estrogen deficiency.

  3. Beta-Adrenergic Agonists

    PubMed Central

    Barisione, Giovanni; Baroffio, Michele; Crimi, Emanuele; Brusasco, Vito

    2010-01-01

    Inhaled β2-adrenoceptor (β2-AR) agonists are considered essential bronchodilator drugs in the treatment of bronchial asthma, both as symptoms-relievers and, in combination with inhaled corticosteroids, as disease-controllers. In this article, we first review the basic mechanisms by which the β2-adrenergic system contributes to the control of airway smooth muscle tone. Then, we go on describing the structural characteristics of β2-AR and the molecular basis of G-protein-coupled receptor signaling and mechanisms of its desensitization/ dysfunction. In particular, phosphorylation mediated by protein kinase A and β-adrenergic receptor kinase are examined in detail. Finally, we discuss the pivotal role of inhaled β2-AR agonists in the treatment of asthma and the concerns about their safety that have been recently raised. PMID:27713285

  4. Melatonin agonists and insomnia.

    PubMed

    Ferguson, Sally A; Rajaratnam, Shantha M W; Dawson, Drew

    2010-02-01

    The ability of melatonin to shift biological rhythms is well known. As a result, melatonin has been used in the treatment of various circadian rhythm sleep disorders, such as advanced and delayed sleep phase disorders, jet lag and shiftwork disorder. The current evidence for melatonin being efficacious in the treatment of primary insomnia is less compelling. The development of agents that are selective for melatonin receptors provides opportunity to further elucidate the actions of melatonin and its receptors and to develop novel treatments for specific types of sleep disorders. The agonists reviewed here - ramelteon, tasimelteon and agomelatine - all appear to be efficacious in the treatment of circadian rhythm sleep disorders and some types of insomnia. However, further studies are required to understand the mechanisms of action, particularly for insomnia. Clinical application of the agonists requires a good understanding of their phase-dependent properties. Long-term effects of melatonin should be evaluated in large-scale, independent randomized controlled trials.

  5. Partial agonistic action of endomorphins in the mouse spinal cord.

    PubMed

    Mizoguchi, H; Wu, H E; Narita, M

    2001-09-07

    The partial agonistic properties of endogenous mu-opioid peptides endomorphin-1 and endomorphin-2 for G-protein activation were determined in the mouse spinal cord, monitoring the increases in guanosine-5'-o-(3-[35S]thio)triphosphate binding. The G-protein activation induced by endogenous opioid peptide beta-endorphin in the spinal cord was significantly, but partially, attenuated by co-incubation with endomorphin-1 or endomorphin-2. The data indicates that endomorphin-1 and endomorphin-2 are endogenous partial agonists for mu-opioid receptor in the mouse spinal cord.

  6. Antidepressant-like Effects of δ Opioid Receptor Agonists in Animal Models

    PubMed Central

    Saitoh, Akiyoshi; Yamada, Mitsuhiko

    2012-01-01

    Recently, δ opioid receptor agonists have been proposed to be attractive targets for the development of novel antidepressants. Several studies revealed that single treatment of δ opioid receptor agonists produce antidepressant-like effects in the forced swimming test, which is one of the most popular animal models for screening antidepressants. In addition, subchronic treatment with δ opioid receptor agonists has been shown to completely attenuate the hyperemotional responses found in olfactory bulbectomized rats. This animal model exhibits hyperemotional behavior that may mimic the anxiety, aggression, and irritability found in depressed patients, suggesting that δ opioid receptor agonists could be effective in the treatment of these symptoms in depression. On the other hand, prototype δ opioid receptor agonists produce convulsive effects, which limit their therapeutic potential and clinical development. In this review, we presented the current knowledge regarding the antidepressant-like effects of δ opioid receptor agonists, which include some recently developed drugs lacking convulsive effects. PMID:23449756

  7. Benzodiazepine agonist and inverse agonist actions on GABAA receptor-operated chloride channels. II. Chronic effects of ethanol

    SciTech Connect

    Buck, K.J.; Harris, R.A. )

    1990-05-01

    Mice were made tolerant to and dependent on ethanol by administration of a liquid diet. Gamma-aminobutyric acid (GABA) receptor-dependent uptake of 36Cl- by mouse cortical microsacs was used to study the actions of benzodiazepine (BZ) agonists and inverse agonists. Chronic exposure to ethanol attenuated the ability of a BZ agonist, flunitrazepam, to augment muscimol-stimulated uptake of 36Cl- and enhanced the actions of BZ inverse agonists, Ro15-4513 (ethyl-8-azido-5,6-dihydro-5-methyl-6-oxo-4H-imidazo(1,4)-benzodiazepine - 3-carboxylate) and DMCM (methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate), to inhibit GABAA receptor-operated chloride channels. Augmentation of chloride flux by pentobarbital was not reduced by chronic ethanol exposure. Attenuation of flunitrazepam efficacy was transient and returned to control levels within 6 to 24 hr after withdrawal from ethanol, but increased sensitivity to Ro15-4513 was observed as long as 8 days after withdrawal. Chronic exposure to ethanol did not alter (3H)SR 95531 (2-(3'-carbethoxy-2'propyl)-3-amino-6-p-methoxyphenylpyridazinium bromide) binding to low-affinity GABAA receptors or muscimol stimulation of chloride flux; and did not alter (3H)Ro15-4513 or (3H)flunitrazepam binding to central BZ receptors or allosteric modulation of this binding by muscimol (i.e., muscimol-shift). These results suggest that chronic exposure to ethanol reduces coupling between BZ agonist sites and the chloride channel, and may be responsible for the development of cross-tolerance between ethanol and BZ agonists. In contrast, coupling between BZ inverse agonist sites and the chloride channel is increased.

  8. Culture-modified bone marrow cells attenuate cardiac and renal injury in a chronic kidney disease rat model via a novel antifibrotic mechanism.

    PubMed

    Yuen, Darren A; Connelly, Kim A; Advani, Andrew; Liao, Christine; Kuliszewski, Michael A; Trogadis, Judy; Thai, Kerri; Advani, Suzanne L; Zhang, Yuan; Kelly, Darren J; Leong-Poi, Howard; Keating, Armand; Marsden, Philip A; Stewart, Duncan J; Gilbert, Richard E

    2010-03-04

    Most forms of chronic kidney disease are characterized by progressive renal and cardiac fibrosis leading to dysfunction. Preliminary evidence suggests that various bone marrow-derived cell populations have antifibrotic effects. In exploring the therapeutic potential of bone marrow derived cells in chronic cardio-renal disease, we examined the anti-fibrotic effects of bone marrow-derived culture modified cells (CMCs) and stromal cells (SCs). In vitro, CMC-conditioned medium, but not SC-conditioned medium, inhibited fibroblast collagen production and cell signalling in response to transforming growth factor-beta. The antifibrotic effects of CMCs and SCs were then evaluated in the 5/6 nephrectomy model of chronic cardio-renal disease. While intravascular infusion of 10(6) SCs had no effect, 10(6) CMCs reduced renal fibrosis compared to saline in the glomeruli (glomerulosclerosis index: 0.8+/-0.1 v 1.9+/-0.2 arbitrary units) and the tubulointersitium (% area type IV collagen: 1.2+/-0.3 v 8.4+/-2.0, p<0.05 for both). Similarly, 10(6) CMCs reduced cardiac fibrosis compared to saline (% area stained with picrosirius red: 3.2+/-0.3 v 5.1+/-0.4, p<0.05), whereas 10(6) SCs had no effect. Structural changes induced by CMC therapy were accompanied by improved function, as reflected by reductions in plasma creatinine (58+/-3 v 81+/-11 micromol/L), urinary protein excretion (9x/divided by 1 v 64x/divided by 1 mg/day), and diastolic cardiac stiffness (left ventricular end-diastolic pressure-volume relationship: 0.030+/-0.003 v 0.058+/-0.011 mm Hg/microL, p<0.05 for all). Despite substantial improvements in structure and function, only rare CMCs were present in the kidney and heart, whereas abundant CMCs were detected in the liver and spleen. Together, these findings provide the first evidence suggesting that CMCs, but not SCs, exert a protective action in cardio-renal disease and that these effects may be mediated by the secretion of diffusible anti-fibrotic factor(s).

  9. Culture-Modified Bone Marrow Cells Attenuate Cardiac and Renal Injury in a Chronic Kidney Disease Rat Model via a Novel Antifibrotic Mechanism

    PubMed Central

    Advani, Andrew; Liao, Christine; Kuliszewski, Michael A.; Trogadis, Judy; Thai, Kerri; Advani, Suzanne L.; Zhang, Yuan; Kelly, Darren J.; Leong-Poi, Howard; Keating, Armand; Marsden, Philip A.; Stewart, Duncan J.; Gilbert, Richard E.

    2010-01-01

    Background Most forms of chronic kidney disease are characterized by progressive renal and cardiac fibrosis leading to dysfunction. Preliminary evidence suggests that various bone marrow-derived cell populations have antifibrotic effects. In exploring the therapeutic potential of bone marrow derived cells in chronic cardio-renal disease, we examined the anti-fibrotic effects of bone marrow-derived culture modified cells (CMCs) and stromal cells (SCs). Methodology/Principal Findings In vitro, CMC-conditioned medium, but not SC-conditioned medium, inhibited fibroblast collagen production and cell signalling in response to transforming growth factor-ß. The antifibrotic effects of CMCs and SCs were then evaluated in the 5/6 nephrectomy model of chronic cardio-renal disease. While intravascular infusion of 106 SCs had no effect, 106 CMCs reduced renal fibrosis compared to saline in the glomeruli (glomerulosclerosis index: 0.8±0.1 v 1.9±0.2 arbitrary units) and the tubulointersitium (% area type IV collagen: 1.2±0.3 v 8.4±2.0, p<0.05 for both). Similarly, 106 CMCs reduced cardiac fibrosis compared to saline (% area stained with picrosirius red: 3.2±0.3 v 5.1±0.4, p<0.05), whereas 106 SCs had no effect. Structural changes induced by CMC therapy were accompanied by improved function, as reflected by reductions in plasma creatinine (58±3 v 81±11 µmol/L), urinary protein excretion (9×/÷1 v 64×/÷1 mg/day), and diastolic cardiac stiffness (left ventricular end-diastolic pressure-volume relationship: 0.030±0.003 v 0.058±0.011 mm Hg/µL, p<0.05 for all). Despite substantial improvements in structure and function, only rare CMCs were present in the kidney and heart, whereas abundant CMCs were detected in the liver and spleen. Conclusions/Significance Together, these findings provide the first evidence suggesting that CMCs, but not SCs, exert a protective action in cardio-renal disease and that these effects may be mediated by the secretion of diffusible anti

  10. Early-outgrowth bone marrow cells attenuate renal injury and dysfunction via an antioxidant effect in a mouse model of type 2 diabetes.

    PubMed

    Zhang, Yanling; Yuen, Darren A; Advani, Andrew; Thai, Kerri; Advani, Suzanne L; Kepecs, David; Kabir, M Golam; Connelly, Kim A; Gilbert, Richard E

    2012-08-01

    Cell therapy has been extensively investigated in heart disease but less so in the kidney. We considered whether cell therapy also might be useful in diabetic kidney disease. Cognizant of the likely need for autologous cell therapy in humans, we sought to assess the efficacy of donor cells derived from both healthy and diabetic animals. Eight-week-old db/db mice were randomized to receive a single intravenous injection of PBS or 0.5 × 10(6) early-outgrowth cells (EOCs) from db/m or db/db mice. Effects were assessed 4 weeks after cell infusion. Untreated db/db mice developed mesangial matrix expansion and tubular epithelial cell apoptosis in association with increased reactive oxygen species (ROS) and overexpression of thioredoxin interacting protein (TxnIP). Without affecting blood glucose or blood pressure, EOCs not only attenuated mesangial and peritubular matrix expansion, as well as tubular apoptosis, but also diminished ROS and TxnIP overexpression in the kidney of db/db mice. EOCs derived from both diabetic db/db and nondiabetic db/m mice were equally effective in ameliorating kidney injury and oxidative stress. The similarly beneficial effects of cells from healthy and diabetic donors highlight the potential of autologous cell therapy in the related clinical setting.

  11. PPAR agonists stimulate adipogenesis at the expense of osteoblast differentiation while inhibiting osteoclast formation and activity.

    PubMed

    Patel, Jessal J; Butters, Oliver R; Arnett, Timothy R

    2014-06-01

    Drugs used in the treatment of type 2 diabetes and cardiovascular disease, specifically peroxisome proliferator-activated receptor (PPAR) agonists, have been reported to affect bone cell function and fracture risk. In this study, we assessed the direct effects of PPAR-γ agonists (rosiglitazone and troglitazone), used in the treatment of diabetes, and a PPAR-α agonist (fenofibrate), used to treat hyperlipidaemia, on the function of primary osteoblasts and osteoclasts. Formation of 'trabecular' bone structures by rat calvarial osteoblasts was reduced by up to 85% in cultures treated with rosiglitazone and by 45% in troglitazone-treated or fenofibrate-treated cultures; at the same time, lipid droplet formation was increased by 40-70%. The expression of key osteogenic markers was similarly downregulated in cultures treated with PPAR agonists, whereas adipogenesis markers were upregulated. Formation of osteoclasts in cultures derived from mouse marrow diminished with fenofibrate treatment, whereas both glitazones reduced resorptive activity without affecting osteoclast number. Metformin, although not a PPAR agonist, is also commonly used in the treatment of type 2 diabetes. Here, metformin was found to have no effect on bone cell function. Taken together, these data suggest that PPAR-γ agonists may enhance bone loss via increased adipogenesis at the expense of osteoblast formation. In contrast, PPAR-α agonists may prevent bone loss. Given that the prevalence of diabetes and cardiovascular disease is expected to rise significantly, greater attention may need to be paid to the effects of PPAR agonists on bone homeostasis. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Bitter Taste Receptor Agonists Mitigate Features of Allergic Asthma in Mice

    PubMed Central

    Sharma, Pawan; Yi, Roslyn; Nayak, Ajay P.; Wang, Nadan; Tang, Francesca; Knight, Morgan J.; Pan, Shi; Oliver, Brian; Deshpande, Deepak A.

    2017-01-01

    Asthma is characterized by airway inflammation, mucus secretion, remodeling and hyperresponsiveness (AHR). Recent research has established the bronchodilatory effect of bitter taste receptor (TAS2R) agonists in various models. Comprehensive pre-clinical studies aimed at establishing effectiveness of TAS2R agonists in disease models are lacking. Here we aimed to determine the effect of TAS2R agonists on features of asthma. Further, we elucidated a mechanism by which TAS2R agonists mitigate features of asthma. Asthma was induced in mice using intranasal house dust mite or aerosol ova-albumin challenge, and chloroquine or quinine were tested in both prophylactic and treatment models. Allergen challenge resulted in airway inflammation as evidenced by increased immune cells infiltration and release of cytokines and chemokines in the lungs, which were significantly attenuated in TAS2R agonists treated mice. TAS2R agonists attenuated features of airway remodeling including smooth muscle mass, extracellular matrix deposition and pro-fibrotic signaling, and also prevented mucus accumulation and development of AHR in mice. Mechanistic studies using human neutrophils demonstrated that inhibition of immune cell chemotaxis is a key mechanism by which TAS2R agonists blocked allergic airway inflammation and exerted anti-asthma effects. Our comprehensive studies establish the effectiveness of TAS2R agonists in mitigating multiple features of allergic asthma. PMID:28397820

  13. Bitter Taste Receptor Agonists Mitigate Features of Allergic Asthma in Mice.

    PubMed

    Sharma, Pawan; Yi, Roslyn; Nayak, Ajay P; Wang, Nadan; Tang, Francesca; Knight, Morgan J; Pan, Shi; Oliver, Brian; Deshpande, Deepak A

    2017-04-11

    Asthma is characterized by airway inflammation, mucus secretion, remodeling and hyperresponsiveness (AHR). Recent research has established the bronchodilatory effect of bitter taste receptor (TAS2R) agonists in various models. Comprehensive pre-clinical studies aimed at establishing effectiveness of TAS2R agonists in disease models are lacking. Here we aimed to determine the effect of TAS2R agonists on features of asthma. Further, we elucidated a mechanism by which TAS2R agonists mitigate features of asthma. Asthma was induced in mice using intranasal house dust mite or aerosol ova-albumin challenge, and chloroquine or quinine were tested in both prophylactic and treatment models. Allergen challenge resulted in airway inflammation as evidenced by increased immune cells infiltration and release of cytokines and chemokines in the lungs, which were significantly attenuated in TAS2R agonists treated mice. TAS2R agonists attenuated features of airway remodeling including smooth muscle mass, extracellular matrix deposition and pro-fibrotic signaling, and also prevented mucus accumulation and development of AHR in mice. Mechanistic studies using human neutrophils demonstrated that inhibition of immune cell chemotaxis is a key mechanism by which TAS2R agonists blocked allergic airway inflammation and exerted anti-asthma effects. Our comprehensive studies establish the effectiveness of TAS2R agonists in mitigating multiple features of allergic asthma.

  14. Upregulation of (C-X-C motif) Ligand 13 (CXCL13) Attenuates Morphine Analgesia in Rats with Cancer-Induced Bone Pain

    PubMed Central

    Wang, Shi-Feng; Dong, Cheng-Gong; Yang, Xue; Yin, Jian-Jun

    2016-01-01

    Background The aim of this study was to investigate the role of chemokine (C-X-C motif) ligand 13 (CXCL13) in morphine tolerance in rats with cancer-induced bone pain (CIBP). Material/Methods We established a rat CIBP model and a rat CIBP-morphine tolerance (BM) model. BM rats were intrathecally administered rmCXCL13, neutralizing anti-CXCL13, and normal saline, while the control group rats underwent a sham operation and were injected with normal saline. The morphine analgesia was assessed by measuring mechanical withdrawal threshold (MWT) and mechanical withdrawal duration (MWD) at various time points. The co-expressions of CXCL13 and NeuN were measured by immunofluorescence double-staining. CXCL13 protein and mRNA expressions were detected by Western blot and quantitative real-time polymerase chain reaction (RT-qPCR), respectively. Results Compared to the sham-operation (S) group, the BM group showed obviously decreased MWT and increased MWD on Day 9 after CIBP, but obviously increased MWT and decreased MWD on Day 3 after morphine administration; subsequently, the MWT was decreased and MWD was increased (all P<0.05). In comparison with the S+saline group, increased MWT and decreased MWD were observed in BM rats on Day 3 after anti-CXCL13 administration, and obviously decreased MWT and increased MWD were found in BM rats on Day 3 after rmCXCL13 administration (all P<0.05). Conclusions Up-regulated CXCL13 has a negative role in morphine analgesia in relief of CIBP, which may provide a new target for the management of CIBP. PMID:27892451

  15. Do all β-blockers attenuate the excess hematopoietic progenitor cell mobilization from the bone marrow following trauma/hemorrhagic shock?

    PubMed

    Pasupuleti, Latha V; Cook, Kristin M; Sifri, Ziad C; Alzate, Walter D; Livingston, David H; Mohr, Alicia M

    2014-04-01

    Severe injury results in increased mobilization of hematopoietic progenitor cells (HPC) from the bone marrow (BM) to sites of injury, which may contribute to persistent BM dysfunction after trauma. Norepinephrine is a known inducer of HPC mobilization, and nonselective β-blockade with propranolol has been shown to decrease mobilization after trauma and hemorrhagic shock (HS). This study will determine the role of selective β-adrenergic receptor blockade in HPC mobilization in a combined model of lung contusion (LC) and HS. Male Sprague-Dawley rats were subjected to LC, followed by 45 minutes of HS. Animals were then randomized to receive atenolol (LCHS + β1B), butoxamine (LCHS + β2B), or SR59230A (LCHS + β3B) immediately after resuscitation and daily for 6 days. Control groups were composed of naive animals. BM cellularity, %HPCs in peripheral blood, and plasma granulocyte-colony stimulating factor levels were assessed at 3 hours and 7 days. Systemic plasma-mediated effects were evaluated in vitro by assessment of BM HPC growth. Injured lung tissue was graded histologically by a blinded reader. The use of β2B or β3B following LCHS restored BM cellularity and significantly decreased HPC mobilization. In contrast, β1B had no effect on HPC mobilization. Only β3B significantly reduced plasma G-CSF levels. When evaluating the plasma systemic effects, both β2B and β3B significantly improved BM HPC growth as compared with LCHS alone. The use of β2 and β3 blockade did not affect lung injury scores. Both β2 and β3 blockade can prevent excess HPC mobilization and BM dysfunction when given after trauma and HS, and the effects seem to be mediated systemically, without adverse effects on subsequent healing. Only treatment with β3 blockade reduced plasma G-CSF levels, suggesting different mechanisms for adrenergic-induced G-CSF release and mobilization of HPCs. This study adds to the evidence that therapeutic strategies that reduce the exaggerated sympathetic

  16. Nonsteroidal 2,3-dihydroquinoline glucocorticoid receptor agonists with reduced PEPCK activation.

    PubMed

    Hudson, Andrew R; Higuchi, Robert I; Roach, Steven L; Valdez, Lino J; Adams, Mark E; Vassar, Angie; Rungta, Deepa; Syka, Peter M; Mais, Dale E; Marschke, Keith B; Zhi, Lin

    2011-03-15

    Continuing studies based on dihydroquinoline glucocorticoid receptor agonists lead to the discovery of a series of C4-oxime analogs. Representative compounds exhibited potent transrepression activity with minimal transactivation of phosphoenolpyruvate caboxykinase (PEPCK), a key protein in the gluconeogenesis pathway. These compounds represent promising leads in identifying GR agonists with high anti-inflammatory activity and attenuated potential for glucose elevation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Photoacoustic computed tomography correcting for heterogeneity and attenuation

    PubMed Central

    Huang, Chao; Nie, Liming; Schoonover, Robert W.

    2012-01-01

    Abstract. We report an investigation of image reconstruction in photoacoustic tomography for objects that possess heterogeneous material and acoustic attenuation distributions. When the object contains materials, such as bone and soft-tissue, that are modeled using power law attenuation models with distinct exponents, we demonstrate that the effects of acoustic attenuation due to the most strongly attenuating material can be compensated for if the attenuation of the other less attenuating material(s) are neglected. Experiments with phantom objects are presented to validated our findings. PMID:22734741

  18. Bitter taste receptor agonists alter mitochondrial function and induce autophagy in airway smooth muscle cells.

    PubMed

    Pan, Shi; Sharma, Pawan; Shah, Sushrut D; Deshpande, Deepak A

    2017-07-01

    Airway remodeling, including increased airway smooth muscle (ASM) mass, is a hallmark feature of asthma and COPD. We previously identified the expression of bitter taste receptors (TAS2Rs) on human ASM cells and demonstrated that known TAS2R agonists could promote ASM relaxation and bronchodilation and inhibit mitogen-induced ASM growth. In this study, we explored cellular mechanisms mediating the antimitogenic effect of TAS2R agonists on human ASM cells. Pretreatment of ASM cells with TAS2R agonists chloroquine and quinine resulted in inhibition of cell survival, which was largely reversed by bafilomycin A1, an autophagy inhibitor. Transmission electron microscope studies demonstrated the presence of double-membrane autophagosomes and deformed mitochondria. In ASM cells, TAS2R agonists decreased mitochondrial membrane potential and increased mitochondrial ROS and mitochondrial fragmentation. Inhibiting dynamin-like protein 1 (DLP1) reversed TAS2R agonist-induced mitochondrial membrane potential change and attenuated mitochondrial fragmentation and cell death. Furthermore, the expression of mitochondrial protein BCL2/adenovirus E1B 19-kDa protein-interacting protein 3 (Bnip3) and mitochondrial localization of DLP1 were significantly upregulated by TAS2R agonists. More importantly, inhibiting Bnip3 mitochondrial localization by dominant-negative Bnip3 significantly attenuated cell death induced by TAS2R agonist. Collectively the TAS2R agonists chloroquine and quinine modulate mitochondrial structure and function, resulting in ASM cell death. Furthermore, Bnip3 plays a central role in TAS2R agonist-induced ASM functional changes via a mitochondrial pathway. These findings further establish the cellular mechanisms of antimitogenic effects of TAS2R agonists and identify a novel class of receptors and pathways that can be targeted to mitigate airway remodeling as well as bronchoconstriction in obstructive airway diseases. Copyright © 2017 the American Physiological

  19. Parathyroid hormone induces bone formation in phosphorylation-deficient PTHR1 knockin mice.

    PubMed

    Datta, Nabanita S; Samra, Tareq A; Abou-Samra, Abdul B

    2012-05-01

    Activation of G protein-coupled receptors by agonists leads to receptor phosphorylation, internalization of ligand receptor complexes, and desensitization of hormonal response. The role of parathyroid hormone (PTH) receptor 1, PTHR1, is well characterized and known to regulate cellular responsiveness in vitro. However, the role of PTHR1 phosphorylation in bone formation is yet to be investigated. We have previously demonstrated that impaired internalization and sustained cAMP stimulation of phosphorylation-deficient (PD) PTHR1 leads to exaggerated cAMP response to subcutaneous PTH infusion in a PD knockin mouse model. To understand the physiological role of receptor internalization on PTH bone anabolic action, we examined bone parameters of wild-type (WT) and PD knockin female and male mice following PTH treatment. We found a decrease in total and diaphyseal bone mineral density in female but not in male PD mice compared with WT controls at 3-6 mo of age. This effect was attenuated at older age groups. PTH administration displayed increased bone volume and trabecular thickness in the vertebrae and distal femora of both WT and PD animals. These results suggest that PTHR1 phosphorylation does not play a major role in the anabolic action of PTH.

  20. Parathyroid hormone induces bone formation in phosphorylation-deficient PTHR1 knockin mice

    PubMed Central

    Samra, Tareq A.; Abou-Samra, Abdul B.

    2012-01-01

    Activation of G protein-coupled receptors by agonists leads to receptor phosphorylation, internalization of ligand receptor complexes, and desensitization of hormonal response. The role of parathyroid hormone (PTH) receptor 1, PTHR1, is well characterized and known to regulate cellular responsiveness in vitro. However, the role of PTHR1 phosphorylation in bone formation is yet to be investigated. We have previously demonstrated that impaired internalization and sustained cAMP stimulation of phosphorylation-deficient (PD) PTHR1 leads to exaggerated cAMP response to subcutaneous PTH infusion in a PD knockin mouse model. To understand the physiological role of receptor internalization on PTH bone anabolic action, we examined bone parameters of wild-type (WT) and PD knockin female and male mice following PTH treatment. We found a decrease in total and diaphyseal bone mineral density in female but not in male PD mice compared with WT controls at 3–6 mo of age. This effect was attenuated at older age groups. PTH administration displayed increased bone volume and trabecular thickness in the vertebrae and distal femora of both WT and PD animals. These results suggest that PTHR1 phosphorylation does not play a major role in the anabolic action of PTH. PMID:22338074

  1. GLP-1R Agonists Modulate Enteric Immune Responses Through the Intestinal Intraepithelial Lymphocyte GLP-1R.

    PubMed

    Yusta, Bernardo; Baggio, Laurie L; Koehler, Jacqueline; Holland, Dianne; Cao, Xiemin; Pinnell, Lee J; Johnson-Henry, Kathene C; Yeung, William; Surette, Michael G; Bang, K W Annie; Sherman, Philip M; Drucker, Daniel J

    2015-07-01

    Obesity and diabetes are characterized by increased inflammation reflecting disordered control of innate immunity. We reveal a local intestinal intraepithelial lymphocyte (IEL)-GLP-1 receptor (GLP-1R) signaling network that controls mucosal immune responses. Glp1r expression was enriched in intestinal IEL preparations and copurified with markers of Tαβ and Tγδ IELs, the two main subsets of intestinal IELs. Exendin-4 increased cAMP accumulation in purified IELs and reduced the production of cytokines from activated IELs but not from splenocytes ex vivo. These actions were mimicked by forskolin, absent in IELs from Glp1r(-/-) mice, and attenuated by the GLP-1R agonist exendin (9-39) consistent with a GLP-1R-dependent mechanism of action. Furthermore, Glp1r(-/-) mice exhibited dysregulated intestinal gene expression, an abnormal representation of microbial species in feces, and enhanced sensitivity to intestinal injury following administration of dextran sodium sulfate. Bone marrow transplantation using wild-type C57BL/6 donors normalized expression of multiple genes regulating immune function and epithelial integrity in Glp1r(-/-) recipient mice, whereas acute exendin-4 administration robustly induced the expression of genes encoding cytokines and chemokines in normal and injured intestine. Taken together, these findings define a local enteroendocrine-IEL axis linking energy availability, host microbial responses, and mucosal integrity to the control of innate immunity.

  2. Evaluation of peroxisome proliferator-activated receptor agonists on interleukin-5-induced eosinophil differentiation

    PubMed Central

    Smith, Steven G; Hill, Mike; Oliveria, John-Paul; Watson, Brittany M; Baatjes, Adrian J; Dua, Benny; Howie, Karen; Campbell, Heather; Watson, Rick M; Sehmi, Roma; Gauvreau, Gail M

    2014-01-01

    Peroxisome proliferator-activated receptor (PPAR) agonists have been suggested as novel therapeutics for the treatment of inflammatory lung disease, such as allergic asthma. Treatment with PPAR agonists has been shown to inhibit airway eosinophilia in murine models of allergic asthma, which can occur through several mechanisms including attenuated generation of chemoattractants (e.g. eotaxin) and decreased eosinophil migrational responses. In addition, studies report that PPAR agonists can inhibit the differentiation of several cell types. To date, no studies have examined the effects of PPAR agonists on interleukin-5 (IL-5) -induced eosinophil differentiation from haemopoietic progenitor cells. Non-adherent mononuclear cells or CD34+ cells isolated from the peripheral blood of allergic subjects were grown for 2 weeks in Methocult® cultures with IL-5 (10 ng/ml) and IL-3 (25 ng/ml) in the presence of 1–1000 nm PPARα agonist (GW9578), PPARβ/δ agonist (GW501516), PPARγ agonist (rosiglitazone) or diluent. The number of eosinophil/basophil colony-forming units (Eo/B CFU) was quantified by light microscopy. The signalling mechanism involved was assessed by phosphoflow. Blood-extracted CD34+ cells cultured with IL-5 or IL-5 + IL-3 formed Eo/B CFU, which were significantly inhibited by rosiglitazone (100 nm, P < 0·01) but not GW9578 or GW501516. In addition, rosglitazone significantly inhibited IL-5-induced phosphorylation of extracellular signal-regulated kinase 1/2. We observed an inhibitory effect of rosiglitazone on eosinophil differentiation in vitro, mediated by attenuation of the extracellular signal-regulated kinase 1/2 signalling pathway. These findings indicate that the PPARγ agonist can attenuate tissue eosinophilia by interfering with local differentiative responses. PMID:24628018

  3. Agonist-activated ion channels

    PubMed Central

    Colquhoun, David

    2006-01-01

    This paper looks at ion channels as an example of the pharmacologist's stock in trade, the action of an agonist on a receptor to produce a response. Looked at in this way, ion channels have been helpful because they are still the only system which is simple enough for quantitative investigation of transduction mechanisms. A short history is given of attempts to elucidate what happens between the time when agonist first binds, and the time when the channel opens. PMID:16402101

  4. Bone Diseases

    MedlinePlus

    ... avoid smoking and drinking too much alcohol. Bone diseases can make bones easy to break. Different kinds ... break Osteogenesis imperfecta makes your bones brittle Paget's disease of bone makes them weak Bones can also ...

  5. Dopamine receptor agonists mediate neuroprotection in malonate-induced striatal lesion in the rat.

    PubMed

    Armentero, Marie-Thérèse; Fancellu, Roberto; Nappi, Giuseppe; Blandini, Fabio

    2002-12-01

    Mitochondrial bioenergetic defects are involved in neurological disorders associated with neuronal damage in the striatum, such as Huntington's disease and cerebral ischemia. The striatal release of neurotransmitters, in particular dopamine, may contribute to the development of the neuronal damage. Recent studies have shown that dopamine agonists may exert neuroprotective effects via multiple mechanisms, including modulation of dopamine release from nigrostriatal dopaminergic terminals. In rats, intrastriatal injection of malonate, a reversible inhibitor of the mitochondrial enzyme succinate dehydrogenase, induces a lesion similar to that observed following focal ischemia or in Huntington's disease. In this study, we used the malonate model to explore the neuroprotective potential of dopamine agonists. Sprague-Dawley rats were injected systemically with increasing concentrations of D(1), D(2), or mixed D(1)/D(2) dopamine agonists prior to malonate intrastriatal insult. Administration of increasing doses of the D(2)-specific agonist quinpirole resulted in increased protection against malonate toxicity. Conversely, the D(1)-specific agonist SKF-38393, as well as the mixed D(1)/D(2) agonist apomorphine, conferred higher neuroprotection at lower than at higher concentrations. Our data suggest that malonate-induced striatal toxicity can be attenuated by systemic administration of dopamine agonists, with D(1) and D(2) agonists showing different profiles of efficacy.

  6. Rotary antenna attenuator

    NASA Technical Reports Server (NTRS)

    Dickinson, R. M.; Hardy, J. C.

    1969-01-01

    Radio frequency attenuator, having negligible insertion loss at minimum attenuation, can be used for making precise antenna gain measurements. It is small in size compared to a rotary-vane attenuator.

  7. Agonist-trafficking and hallucinogens.

    PubMed

    González-Maeso, Javier; Sealfon, Stuart C

    2009-01-01

    Seven transmembrane domain receptors, also termed G protein-coupled receptors (GPCRs), represent the most common molecular target for therapeutic drugs. The generally accepted pharmacological model for GPCR activation is the ternary complex model, in which GPCRs exist in a dynamic equilibrium between the active and inactive conformational states. However, the demonstration that different agonists sometimes elicit a different relative activation of two signaling pathways downstream of the same receptor has led to a revision of the ternary complex model. According to this agonist- trafficking model, agonists stabilize distinct activated receptor conformations that preferentially activate specific signaling pathways. Hallucinogenic drugs and non-hallucinogenic drugs represent an attractive experimental system with which to study agonist-trafficking of receptor signaling. Thus many of the behavioral responses induced by hallucinogenic drugs, such as lysergic acid diethylamide (LSD), psilocybin or mescaline, depend on activation of serotonin 5-HT(2A) receptors (5-HT2ARs). In contrast, this neuropsychological state in humans is not induced by closely related chemicals, such as lisuride or ergotamine, despite their similar in vitro activity at the 5-HT2AR. In this review, we summarize the current knowledge, as well as unresolved questions, regarding agonist-trafficking and the mechanism of action of hallucinogenic drugs.

  8. Agonists for the Chemokine Receptor CXCR4

    PubMed Central

    2011-01-01

    The development of agonists for the chemokine receptor CXCR4 could provide promising therapeutic candidates. On the basis of previously forwarded two site model of chemokine–receptor interactions, we hypothesized that linking the agonistic N-terminus of SDF-1 to the T140 backbone would yield new high-affinity agonists of CXCR4. We developed chimeras with the agonistic SDF-1 N-terminus grafted to a T140 side chain and tested their binding affinity and chemotactic agonist activity. While chimeras with the peptide grafted onto position 12 of T140 remained high-affinity antagonists, those bearing the peptide on position 14 were in part agonists. One chimera was a full CXCR4 agonist with 25 nM affinity, and several chimeras showed low nanomolar affinities with partial agonist activity. Our results confirmed that we have developed high-affinity agonists of CXCR4. PMID:21841963

  9. Diabetes and bone health.

    PubMed

    Antonopoulou, Marianna; Bahtiyar, Gül; Banerji, Mary Ann; Sacerdote, Alan S

    2013-11-01

    The increasing prevalence of diabetes especially type 2 diabetes worldwide is indisputable. Diabetics suffer increased morbidity and mortality, compared to their non-diabetic counterparts, not only because of vascular complications, but also because of an increased fracture incidence. Both types 1 and 2 diabetes and some medications used to treat it are associated with osteoporotic fractures. The responsible mechanisms remain incompletely elucidated. In this review, we evaluate the role of glycemic control in bone health, and the effect of anti-diabetic medications such as thiazolidinediones, sulfonylureas, DPP-4 inhibitors, and GLP-1 agonists. In addition, we examine the possible role of insulin and metformin as anabolic agents for bone. Lastly, we identify the current and future screening tools that help evaluate bone health in diabetics and their limitations. In this way we can offer individualized treatment, to the at-risk diabetic population.

  10. Potential effect of angiotensin II receptor blockade in adipose tissue and bone.

    PubMed

    Nakagami, Hironori; Osako, Mariana Kiomy; Morishita, Ryuichi

    2013-01-01

    Recent evidence demonstrated that dysregulation of adipocytokine functions seen in abdominal obesity may be involved in the pathogenesis of the metabolic syndrome. Angiotensinogen, the precursor of angiotensin (Ang) II, is produced primarily in the liver, and also in adipose tissue, where it is up-regulated during the development of obesity and involved in blood pressure regulation and adipose tissue growth. Blockade of renin-angiotensin system (RAS) attenuates weight gain and adiposity by enhanced energy expenditure, and the favorable metabolic effects of telmisartan have been related to its Ang II receptor blockade and action as a partial agonist of peroxisome proliferators activated receptor (PPAR)-γ. PPARγ plays an important role in regulating carbohydrate and lipid metabolism, and ligands for PPARγ can improve insulin sensitivity and reduce triglyceride levels. Similarly, bone metabolism is closely regulated by hormones and cytokines, which have effects on both bone resorption and deposition. It is known that the receptors of Ang II are expressed in culture osteoclasts and osteoblasts, and Ang II is postulated to be able to act upon the cells involved in bone metabolism. In in vitro system, Ang II induced the differentiation and activation of osteoclasts responsible for bone resorption. Importantly, it was demonstrated by the sub-analysis of a recent clinical study that the fracture risk was significantly reduced by the usage of angiotensin-converting enzyme inhibitors. To treat the subgroups of hypertensive patients with osteoporosis RAS can be considered a novel target.

  11. Dissociated sterol-based liver X receptor agonists as therapeutics for chronic inflammatory diseases.

    PubMed

    Yu, Shan; Li, Sijia; Henke, Adam; Muse, Evan D; Cheng, Bo; Welzel, Gustav; Chatterjee, Arnab K; Wang, Danling; Roland, Jason; Glass, Christopher K; Tremblay, Matthew

    2016-07-01

    Liver X receptor (LXR), a nuclear hormone receptor, is an essential regulator of immune responses. Activation of LXR-mediated transcription by synthetic agonists, such as T0901317 and GW3965, attenuates progression of inflammatory disease in animal models. However, the adverse effects of these conventional LXR agonists in elevating liver lipids have impeded exploitation of this intriguing mechanism for chronic therapy. Here, we explore the ability of a series of sterol-based LXR agonists to alleviate inflammatory conditions in mice without hepatotoxicity. We show that oral treatment with sterol-based LXR agonists in mice significantly reduces dextran sulfate sodium colitis-induced body weight loss, which is accompanied by reduced expression of inflammatory markers in the large intestine. The anti-inflammatory property of these agonists is recapitulated in vitro in mouse lamina propria mononuclear cells, human colonic epithelial cells, and human peripheral blood mononuclear cells. In addition, treatment with LXR agonists dramatically suppresses inflammatory cytokine expression in a model of traumatic brain injury. Importantly, in both disease models, the sterol-based agonists do not affect the liver, and the conventional agonist T0901317 results in significant liver lipid accumulation and injury. Overall, these results provide evidence for the development of sterol-based LXR agonists as novel therapeutics for chronic inflammatory diseases.-Yu, S., Li, S., Henke, A., Muse, E. D., Cheng, B., Welzel, G., Chatterjee, A. K., Wang, D., Roland, J., Glass, C. K., Tremblay, M. Dissociated sterol-based liver X receptor agonists as therapeutics for chronic inflammatory diseases. © FASEB.

  12. Adenosine 2A receptor agonism: A single intrathecal administration attenuates motor paralysis in experimental autoimmune encephalopathy in rats.

    PubMed

    Loram, Lisa C; Strand, Keith A; Taylor, Frederick R; Sloane, Evan; Van Dam, Anne-Marie; Rieger, Jayson; Maier, Steven F; Watkins, Linda R

    2015-05-01

    A single intrathecal dose of adenosine 2A receptor (A2AR) agonist was previously reported to produce a multi-week reversal of allodynia in two different models of neuropathic pain in addition to downregulating glial activation markers in the spinal cord. We aimed to determine whether a single intrathecal administration of an A2AR agonist was able to attenuate motor symptoms induced by experimental autoimmune encephalopathy. Two A2AR agonists (CGS21680 and ATL313) significantly attenuated progression of motor symptoms following a single intrathecal administration at the onset of motor symptoms. OX-42, a marker of microglial activation, was significantly attenuated in the lumbar spinal cord following A2AR administration compared to vehicle. Therefore, A2AR agonists attenuate motor symptoms of EAE by acting on A2AR in the spinal cord.

  13. JiangTang XiaoKe granule attenuates cathepsin K expression and improves IGF-1 expression in the bone of high fat diet induced KK-Ay diabetic mice.

    PubMed

    Guo, Yubo; Wang, Lili; Ma, Rufeng; Mu, Qianqian; Yu, Na; Zhang, Yi; Tang, Yuqing; Li, Yu; Jiang, Guangjian; Zhao, Dandan; Mo, Fangfang; Gao, Sihua; Yang, Meijuan; Kan, Feifei; Ma, Qun; Fu, Min; Zhang, Dongwei

    2016-03-01

    To assess the beneficial effects of JiangTang XiaoKe (JTXK) granule on the bone metabolism in high fat diet (HFD) fed KK-Ay diabetic mice. The KK-Ay mice were used as a diabetic model, while C57BL/6 mice were utilized as the non-diabetic control. The left tibia was used for determining bone mineral density (BMD) and bone ash coefficient. The HE and alizarin red S staining of femur were employed to evaluate bone pathology and calcium deposition. The expressions of alkaline phosphatase (ALP), insulin growth factor 1 (IGF-1) and cathepsin K were assessed by western blotting and immunohistochemical staining. JTXK granule significantly improved the bone ash coefficient, the distribution of trabecular bone and the calcification nodules deposition in KK-Ay mice with diabetes. IGF-1 and ALP expressions were significantly decreased, and cathepsin K expression was dramatically increased in the HFD fed KK-Ay diabetic model mice, which can be reversed by JTXK granule treatment. JTXK granule at medium or high dosage was more efficient in improving diabetic bone quality when compared with that in mice with a low dosage. However, the BMD values in each group of KK-Ay diabetic mice were not significantly different. We demonstrate that cathepsin K expression is increased in KK-Ay diabetic mouse model. JTXK granule treatment inhibits osteoclastic bone resorption and promotes the new bone formation by decreasing cathepsin K activity and increasing IGF-1 and ALP levels. These changes may contribute to the increase of bone strength and thus reducing the risk of bone fractures. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. DC attenuation meter

    DOEpatents

    Hargrove, Douglas L.

    2004-09-14

    A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.

  15. Dopamine agonist therapy in hyperprolactinemia.

    PubMed

    Webster, J

    1999-12-01

    Introduction of the dopamine agonist bromocriptine heralded a major advance in the management of hyperprolactinemic disorders. Although its side effects of nausea, dizziness and headache and its short elimination half-life are limiting factors, its efficacy established it as a reference compound against the activity of which several dopamine agonists, like pergolide, lysuride, metergoline, terguride and dihydroergocristine, fell by the wayside. More recently, two new agents, cabergoline and quinagolide, have been introduced and appear to offer considerable advantages over bromocriptine. Cabergoline, an ergoline D2 agonist, has a long plasma half-life that enables once- or twice-weekly administration. Quinagolide, in contrast, is a nonergot D2 agonist with an elimination half-life intermediate between those of bromocriptine and cabergoline, allowing the drug to be administered once daily. Comparative studies indicate that cabergoline is clearly superior to bromocriptine in efficacy (prolactin suppression, restoration of gonadal function) and in tolerability. In similar studies, quinagolide appeared to have similar efficacy and superior tolerability to that of bromocriptine. Results of a small crossover study indicate that cabergoline is better tolerated, with a trend toward activity superior to that of quinagolide. In hyperprolactinemic men and in women not seeking to become pregnant, cabergoline may be regarded as the treatment of choice.

  16. Des-Aspartate-Angiotensin I Attenuates Mortality of Mice Exposed to Gamma Radiation via a Novel Mechanism of Action.

    PubMed

    Wang, Hong; Sethi, Gautam; Loke, Weng-Keong; Sim, Meng-Kwoon

    2015-01-01

    ACE inhibitors and ARBs (angiotensin receptor blockers) have been shown to attenuate radiation injuries in animal models of lethal gamma irradiation. These two classes of drug act by curtailing the actions of angiotensin II-linked inflammatory pathways that are up-regulated during gamma radiation in organ systems such as the brain, lung, kidney, and bone marrow. ACE inhibitors inhibit ACE and attenuate the formation of angiotensin II from angiotensin I; ARBs block the angiotensin AT1 receptor and attenuate the actions of angiotensin II that are elicited through the receptor. DAA-I (des-aspartate-angiotensin I), an orally active angiotensin peptide, also attenuates the deleterious actions of angiotensin II. It acts as an agonist on the angiotensin AT1 receptor and elicits responses that oppose those of angiotensn II. Thus, DAA-I was investigated for its anticipated radioprotection in gamma irradiated mice. DAA-I administered orally at 800 nmole/kg/day for 30 days post exposure (6.4 Gy) attenuated the death of mice during the 30-day period. The attenuation was blocked by losartan (50 nmole/kg/day, i.p.) that was administered sequential to DAA-I administration. This shows that the radioprotection was mediated via the angiotensin AT1 receptor. Furthermore, the radioprotection correlated to an increase in circulating PGE2 of surviving animals, and this suggests that PGE2 is involved in the radioprotection in DAA-I-treated mice. At the hematopoietic level, DAA-I significantly improved two syndromes of myelosuppression (leucopenia and lymphocytopenia), and mice pre-treated with DAA-I prior to gamma irradiation showed significant improvement in the four myelodysplastic syndromes that were investigated, namely leucopenia, lymphocytopenia, monocytopenia and thrombocytopenia. Based on the known ability of PGE2 to attenuate the loss of functional hematopoietic stem and progenitor cells in radiation injury, we hypothesize that PGE2 mediated the action of DAA-I. DAA-I completely

  17. Des-Aspartate-Angiotensin I Attenuates Mortality of Mice Exposed to Gamma Radiation via a Novel Mechanism of Action

    PubMed Central

    Wang, Hong; Sethi, Gautam; Loke, Weng-Keong; Sim, Meng-Kwoon

    2015-01-01

    ACE inhibitors and ARBs (angiotensin receptor blockers) have been shown to attenuate radiation injuries in animal models of lethal gamma irradiation. These two classes of drug act by curtailing the actions of angiotensin II-linked inflammatory pathways that are up-regulated during gamma radiation in organ systems such as the brain, lung, kidney, and bone marrow. ACE inhibitors inhibit ACE and attenuate the formation of angiotensin II from angiotensin I; ARBs block the angiotensin AT1 receptor and attenuate the actions of angiotensin II that are elicited through the receptor. DAA-I (des-aspartate-angiotensin I), an orally active angiotensin peptide, also attenuates the deleterious actions of angiotensin II. It acts as an agonist on the angiotensin AT1 receptor and elicits responses that oppose those of angiotensn II. Thus, DAA-I was investigated for its anticipated radioprotection in gamma irradiated mice. DAA-I administered orally at 800 nmole/kg/day for 30 days post exposure (6.4 Gy) attenuated the death of mice during the 30-day period. The attenuation was blocked by losartan (50 nmole/kg/day, i.p.) that was administered sequential to DAA-I administration. This shows that the radioprotection was mediated via the angiotensin AT1 receptor. Furthermore, the radioprotection correlated to an increase in circulating PGE2 of surviving animals, and this suggests that PGE2 is involved in the radioprotection in DAA-I-treated mice. At the hematopoietic level, DAA-I significantly improved two syndromes of myelosuppression (leucopenia and lymphocytopenia), and mice pre-treated with DAA-I prior to gamma irradiation showed significant improvement in the four myelodysplastic syndromes that were investigated, namely leucopenia, lymphocytopenia, monocytopenia and thrombocytopenia. Based on the known ability of PGE2 to attenuate the loss of functional hematopoietic stem and progenitor cells in radiation injury, we hypothesize that PGE2 mediated the action of DAA-I. DAA-I completely

  18. Bone Healing: Little Secrets

    PubMed Central

    Einhorn, T. A.

    2010-01-01

    The ability to stimulate bone repair, heal non-unions, or restore lost segments of bone is a common goal among orthopaedic surgeons, trauma surgeons, and scientists who investigate wound healing responses. The stimulation of bone repair has been reported using biophysical means such as electromagnetic fields, low-intensity pulsed ultrasound and extracorporeal shockwave therapy. Reported studies on the use of these modalities suggest beneficial effects but the quality of the evidence and high between-study heterogeneity leave the impact of these biophysical stimuli on bone repair uncertain. New biotechnologies to enhance skeletal repair have focused on growth factors, osteoinductive molecules, and, more recently, autologous adult bone marrow stem cells. Recent randomized, placebo-controlled clinical trials using recombinant human fibroblast growth factor-2 for the treatment of tibial shaft fractures, and platelet-derived growth factor for the treatment of ankle fractures have yielded potentially interesting results. More data are needed to confirm these findings. Investigations using prostaglandin EP-2 receptor agonists to enhance tibia shaft fracture healing are also under way. Clinicians and scientists have utilized autologous bone marrow for over a century. Unprocessed preparations have shown uneven results with regard to their ability to enhance bone repair. Recent data, however, demonstrating the use of autologous bone marrow stem cells in a concentrated manner have been very encouraging. Injection of bone marrow aspirate concentrate into non-unions and in conjunction with local bone for the enhancement of spinal fusion have shown impressive results. Perhaps the most well-investigated biotechnology for the enhancement of bone repair is the use of the bone morphogenetic proteins. BMP-2 and BMP-7 are now available as recombinant molecules and have been evaluated in both spinal and long-bone trauma applications. RhBMP-2 has demonstrated efficacy in the enhancement

  19. Heptamethoxyflavone, a citrus flavonoid, suppresses inflammatory osteoclastogenesis and alveolar bone resorption.

    PubMed

    Matsumoto, Chiho; Inoue, Hiroki; Tominari, Tsukasa; Watanabe, Kenta; Hirata, Michiko; Miyaura, Chisato; Inada, Masaki

    2015-01-01

    We examined the effects of heptamethoxyflavone (HMF), a citrus flavonoid on inflammatory bone resorption. HMF suppressed the osteoclast formation and PGE2 production induced by IL-1. In mouse calvarial organ cultures, HMF attenuated the bone resorption elicited by LPS. HMF suppressed bone resorption in the mandibular alveolar bone. HMF may protect against inflammatory bone loss such as periodontal disease.

  20. Cangrelor attenuates coated-platelet formation.

    PubMed

    Norgard, Nicholas B; Hann, Callie L; Dale, George L

    2009-01-01

    P2Y(12) inhibitors were introduced clinically as effective inhibitors of adenosine-5'-diphosphate (ADP) mediated platelet activation and aggregation. This class of pharmacological agents has enjoyed considerable success. Cangrelor is a recently developed P2Y(12) inhibitor that has the advantage of being an active drug not requiring metabolic conversion, although it is not orally available. Coated-platelets are a subclass of activated platelets generated on dual agonist activation with collagen plus thrombin; the primary hallmark of coated-platelets is their ability to support prothrombinase activity. Interestingly, we recently observed that the relatively weak agonist ADP potentiates the production of coated-platelets by the very strong agonists collagen plus thrombin, a previously unknown role for ADP. The authors sought in this study to determine if P2Y(12) inhibitors, such as cangrelor, were capable of attenuating this augmentation of coated-platelet generation. Cangrelor, at physiologically relevant concentrations, was able to eliminate the ADP-dependent increase in coated-platelet production with an IC(50) of 1.4 nM. Cangrelor, however, had no effect on thrombin-dependent platelet activation as measured by P-selectin expression. Although this in vitro study does not address the question of whether the effectiveness of cangrelor in vivo is partially due to an attenuation of coated-platelet production in addition to its documented antiaggregatory effects, it does reveal an unexpected action of cangrelor. Additional studies will be required to determine if all P2Y(12) inhibitors are equally effective in attenuating coated-platelet production.

  1. Novel diazabicycloalkane delta opioid agonists.

    PubMed

    Loriga, Giovanni; Lazzari, Paolo; Manca, Ilaria; Ruiu, Stefania; Falzoi, Matteo; Murineddu, Gabriele; Bottazzi, Mirko Emilio Heiner; Pinna, Giovanni; Pinna, Gérard Aimè

    2015-09-01

    Here we report the investigation of diazabicycloalkane cores as potential new scaffolds for the development of novel analogues of the previously reported diazatricyclodecane selective delta (δ) opioid agonists, as conformationally constrained homologues of the reference δ agonist (+)-4-[(αR)-α((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC80). In particular, we have simplified the diazatricyclodecane motif of δ opioid agonist prototype 1a with bridged bicyclic cores. 3,6-diazabicyclo[3.1.1]heptane, 3,8-diazabicyclo[3.2.1]octane, 3,9-diazabicyclo[3.3.1]nonane, 3,9-diazabicyclo[4.2.1]nonane, and 3,10-diazabicyclo[4.3.1]decane were adopted as core motifs of the novel derivatives. The compounds were synthesized and biologically assayed as racemic (3-5) or diastereoisomeric (6,7) mixtures. All the novel compounds 3-7 showed δ agonism behaviour and remarkable affinity to δ receptors. Amongst the novel derivatives, 3,8-diazabicyclo[3.2.1]octane based compound 4 evidenced improved δ affinity and selectivity relative to SNC80. Published by Elsevier Ltd.

  2. Pressure surge attenuator

    DOEpatents

    Christie, Alan M.; Snyder, Kurt I.

    1985-01-01

    A pressure surge attenuation system for pipes having a fluted region opposite crushable metal foam. As adapted for nuclear reactor vessels and heads, crushable metal foam is disposed to attenuate pressure surges.

  3. Living Bones, Strong Bones

    NASA Image and Video Library

    In this classroom activity, engineering, nutrition, and physical activity collide when students design and build a healthy bone model of a space explorer which is strong enough to withstand increas...

  4. Suppression of atherosclerosis by synthetic REV-ERB agonist

    SciTech Connect

    Sitaula, Sadichha; Billon, Cyrielle; Kamenecka, Theodore M.; Solt, Laura A.; Burris, Thomas P.

    2015-05-08

    The nuclear receptors for heme, REV-ERBα and REV-ERBβ, play important roles in the regulation of metabolism and inflammation. Recently it was demonstrated that reduced REV-ERBα expression in hematopoetic cells in LDL receptor null mice led to increased atherosclerosis. We sought to determine if synthetic REV-ERB agonists that we have developed might have the ability to suppress atherosclerosis in this model. A previously characterized synthetic REV-ERB agonist, SR9009, was used to determine if activation of REV-ERB activity would affect atherosclerosis in LDL receptor deficient mice. Atherosclerotic plaque size was significantly reduced (p < 0.05) in mice administered SR9009 (100 mg/kg) for seven weeks compared to control mice (n = 10 per group). SR9009 treatment of bone marrow-derived mouse macrophages (BMDM) reduced the polarization of BMDMs to proinflammatory M1 macrophage while increasing the polarization of BMDMs to anti-inflammatory M2 macrophages. Our results suggest that pharmacological targeting of REV-ERBs may be a viable therapeutic option for treatment of atherosclerosis. - Highlights: • Synthetic REV-ERB agonist treatment reduced atherosclerosis in a mouse model. • Pharmacological activation of REV-ERB decreased M1 macrophage polarization. • Pharmacological activation of REV-ERB increased M2 macrophage polarization.

  5. Regulation of membrane cholecystokinin-2 receptor by agonists enables classification of partial agonists as biased agonists.

    PubMed

    Magnan, Rémi; Masri, Bernard; Escrieut, Chantal; Foucaud, Magali; Cordelier, Pierre; Fourmy, Daniel

    2011-02-25

    Given the importance of G-protein-coupled receptors as pharmacological targets in medicine, efforts directed at understanding the molecular mechanism by which pharmacological compounds regulate their presence at the cell surface is of paramount importance. In this context, using confocal microscopy and bioluminescence resonance energy transfer, we have investigated internalization and intracellular trafficking of the cholecystokinin-2 receptor (CCK2R) in response to both natural and synthetic ligands with different pharmacological features. We found that CCK and gastrin, which are full agonists on CCK2R-induced inositol phosphate production, rapidly and abundantly stimulate internalization. Internalized CCK2R did not rapidly recycle to plasma membrane but instead was directed to late endosomes/lysosomes. CCK2R endocytosis involves clathrin-coated pits and dynamin and high affinity and prolonged binding of β-arrestin1 or -2. Partial agonists and antagonists on CCK2R-induced inositol phosphate formation and ERK1/2 phosphorylation did not stimulate CCK2R internalization or β-arrestin recruitment to the CCK2R but blocked full agonist-induced internalization and β-arrestin recruitment. The extreme C-terminal region of the CCK2R (and more precisely phosphorylatable residues Ser(437)-Xaa(438)-Thr(439)-Thr(440)-Xaa(441)-Ser(442)-Thr(443)) were critical for β-arrestin recruitment. However, this region and β-arrestins were dispensable for CCK2R internalization. In conclusion, this study allowed us to classify the human CCK2R as a member of class B G-protein-coupled receptors with regard to its endocytosis features and identified biased agonists of the CCK2R. These new important insights will allow us to investigate the role of internalized CCK2R·β-arrestin complexes in cancers expressing this receptor and to develop new diagnosis and therapeutic strategies targeting this receptor.

  6. Bone Cancer

    MedlinePlus

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

  7. Cannabinoid receptor 2 and its agonists mediate hematopoiesis and hematopoietic stem and progenitor cell mobilization

    PubMed Central

    Jiang, Shuxian; Alberich-Jorda, Meritxell; Zagozdzon, Radoslaw; Parmar, Kalindi; Fu, Yigong; Mauch, Peter; Banu, Naheed; Makriyannis, Alexandros; Tenen, Daniel G.; Avraham, Shalom; Groopman, Jerome E.

    2011-01-01

    Endocannabinoids are arachidonic acid derivatives and part of a novel bioactive lipid signaling system, along with their G-coupled cannabinoid receptors (CB1 and CB2) and the enzymes involved in their biosynthesis and degradation. However, their roles in hematopoiesis and hematopoietic stem and progenitor cell (HSPC) functions are not well characterized. Here, we show that bone marrow stromal cells express endocannabinoids (anandamide and 2-arachidonylglycerol), whereas CB2 receptors are expressed in human and murine HSPCs. On ligand stimulation with CB2 agonists, CB2 receptors induced chemotaxis, migration, and enhanced colony formation of bone marrow cells, which were mediated via ERK, PI3-kinase, and Gαi-Rac1 pathways. In vivo, the CB2 agonist AM1241 induced mobilization of murine HSPCs with short- and long-term repopulating abilities. In addition, granulocyte colony-stimulating factor -induced mobilization of HSPCs was significantly decreased by specific CB2 antagonists and was impaired in Cnr2−/− cannabinoid type 2 receptor knockout mice. Taken together, these results demonstrate that the endocannabinoid system is involved in hematopoiesis and that CB2/CB2 agonist axis mediates repopulation of hematopoiesis and mobilization of HSPCs. Thus, CB2 agonists may be therapeutically applied in clinical conditions, such as bone marrow transplantation. PMID:21063029

  8. Tracer attenuation in groundwater

    NASA Astrophysics Data System (ADS)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  9. Population pharmacokinetics and pharmacodynamics of peptidic erythropoiesis receptor agonist (ERA) in healthy volunteers.

    PubMed

    Woo, Sukyung; Krzyzanski, Wojciech; Duliege, Anne-Marie; Stead, Richard B; Jusko, William J

    2008-01-01

    Peptidic erythropoiesis receptor agonist is a synthetic, PEGylated peptide that can promote red blood cell production upon binding to the erythropoietin receptor. The objective of this study was to characterize the pharmacokinetics and erythropoietic effects of peptidic erythropoiesis receptor agonist in healthy volunteers. Plasma concentrations of peptidic erythropoiesis receptor agonist and pharmacodynamic responses were obtained after single intravenous injections at doses of 0.025, 0.05, and 0.1 mg/kg. Population pharmacokinetic/pharmacodynamic modeling was performed using NONMEM. Peptidic erythropoiesis receptor agonist exhibited nonlinear pharmacokinetics described by a 1-compartment model with parallel elimination by Michaelis-Menten and linear processes. A catenary, life span-based, indirect response model reflecting bone marrow erythroid and blood cells reflected the pharmacodynamics of peptidic erythropoiesis receptor agonist. A modest tolerance and rebound phenomenon in reticulocytes was modeled with negative feedback regulation related to hemoglobin. This pharmacokinetic/pharmacodynamic model well characterized the prolonged disposition, intrinsic pharmacologic parameters, and typical hematological system properties following single doses of peptidic erythropoiesis receptor agonist in normal subjects.

  10. Bone and bone turnover.

    PubMed

    Crofton, Patricia M

    2009-01-01

    Children with cancer are exposed to multiple influences that may adversely affect bone health. Some treatments have direct deleterious effects on bone whilst others may have indirect effects mediated through various endocrine abnormalities. Most clinical outcome studies have concentrated on survivors of acute lymphoblastic leukaemia (ALL). There is now good evidence that earlier treatment protocols that included cranial irradiation with doses of 24 Gy or greater may result in growth hormone deficiency and low bone mineral density (BMD) in the lumbar spine and femoral neck. Under current protocols, BMD decreases during intensive chemotherapy and fracture risk increases. Although total body BMD may eventually return to normal after completion of chemotherapy, lumbar spine trabecular BMD may remain low for many years. The implications for long-term fracture risk are unknown. Risk factors for low BMD include high dose methotrexate, higher cumulative doses of glucocorticoids, male gender and low physical activity. BMD outcome in non-ALL childhood cancers has been less well studied but there is evidence that survivors of childhood brain or bone tumours, and survivors of bone marrow transplants for childhood malignancy, all have a high risk of long-term osteopenia. Long-term follow-up is required, with appropriate treatment of any endocrine abnormalities identified.

  11. Kappa Opioid Receptor Agonist and Brain Ischemia

    PubMed Central

    Chunhua, Chen; Chunhua, Xi; Megumi, Sugita; Renyu, Liu

    2014-01-01

    Opioid receptors, especially Kappa opioid receptor (KOR) play an important role in the pathophysiological process of cerebral ischemia reperfusion injury. Previously accepted KOR agonists activity has included anti-nociception, cardiovascular, anti-pruritic, diuretic, and antitussive effects, while compelling evidence from various ischemic animal models indicate that KOR agonist have neuroprotective effects through various mechanisms. In this review, we aimed to demonstrate the property of KOR agonist and its role in global and focal cerebral ischemia. Based on current preclinical research, the KOR agonists may be useful as a neuroprotective agent. The recent discovery of salvinorin A, highly selective non-opioid KOR agonist, offers a new tool to study the role of KOR in brain HI injury and the protective effects of KOR agonist. The unique pharmacological profile of salvinorin A along with the long history of human usage provides its high candidacy as a potential alternative medication for brain HI injury. PMID:25574482

  12. Kappa Opioid Receptor Agonist and Brain Ischemia.

    PubMed

    Chunhua, Chen; Chunhua, Xi; Megumi, Sugita; Renyu, Liu

    2014-01-01

    Opioid receptors, especially Kappa opioid receptor (KOR) play an important role in the pathophysiological process of cerebral ischemia reperfusion injury. Previously accepted KOR agonists activity has included anti-nociception, cardiovascular, anti-pruritic, diuretic, and antitussive effects, while compelling evidence from various ischemic animal models indicate that KOR agonist have neuroprotective effects through various mechanisms. In this review, we aimed to demonstrate the property of KOR agonist and its role in global and focal cerebral ischemia. Based on current preclinical research, the KOR agonists may be useful as a neuroprotective agent. The recent discovery of salvinorin A, highly selective non-opioid KOR agonist, offers a new tool to study the role of KOR in brain HI injury and the protective effects of KOR agonist. The unique pharmacological profile of salvinorin A along with the long history of human usage provides its high candidacy as a potential alternative medication for brain HI injury.

  13. Alpha2-adrenergic receptor agonists as analgesics.

    PubMed

    Boyd, R E

    2001-08-01

    Alpha2-adrenergic receptor agonists are analgesic agents, and the alpha2-adrenergic agonist clonidine has been used in clinical studies for regional analgesia after intrathecal administration. We review here recent developments concerning the structure activity relationships of a new class of potent alpha2-adrenergic agonists and their use as analgesic agents. The effect of structure upon cardiovascular side-effects is also monitored, such as the prolongation of the QT portion of the cardiac action potential.

  14. Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness – A Case Study on Osteoporosis Rat Bone

    PubMed Central

    Wu, Yuchin; Adeeb, Samer; Doschak, Michael R.

    2015-01-01

    Micro-computed tomography (Micro-CT) images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone microarchitectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA) can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of Micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived grayscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two- and three-dimensional bone microarchitecture from sham and ovariectomized (OVX) rats (n = 10/group). A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA, because Micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three-dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation, and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading. PMID:26042089

  15. [Non-corticosteroid drug-induced metabolic bone disease].

    PubMed

    Briot, Karine

    2006-10-01

    After osteoporotic fracture or low bone mineral density measurements, it is necessary to look for secondary causes of osteoporosis, such as drugs. Corticosteroids are the most common cause of drug-induced metabolic bone disease. Other drugs responsible for bone disease include: aromatase inhibitors, GnRH agonists, anticonvulsants, heparin, and L thyroxin at TSH-suppressive doses. Confirmation is required of data about neuroleptics and antivitamin K.

  16. Antihyperalgesic effects of δ opioid agonists in a rat model of chronic inflammation

    PubMed Central

    Fraser, Graeme L; Gaudreau, Geneviève-Anne; Clarke, Paul B S; Ménard, Daniel P; Perkins, Martin N

    2000-01-01

    Opioid receptors in the brain activate descending pain pathways to inhibit the nociceptive response to acute noxious stimuli. The aim of the present study was to clarify the role of supraspinal opioid receptors in modulating the nociceptive response to persistent inflammation in rats.Subcutaneous administration of 50 μl of complete Freund's Adjuvant (CFA) into the plantar surface of the hindpaw induced a significant decrease in paw withdrawal latency to thermal stimuli (P<0.01) at 24 h post-injection.Intracerebroventricular (i.c.v.) administration of the μ opioid receptor agonists, DAMGO and morphine, and the δ opioid receptor agonists, deltorphin II and SNC80, significantly reversed the hyperalgesic response associated with peripheral inflammation in a dose-dependent manner (P<0.0001).The μ and δ agonists also significantly attenuated the antinociceptive response to acute thermal stimulation in rats (P<0.001). However, deltorphin II and SNC80 were less potent, and in the case of SNC80 less efficacious, in modulating the response to acute thermal nociception in comparison to hyperalgesia associated with persistent inflammation.These results indicate that μ and δ opioid receptors in the brain modulate descending pain pathways to attenuate the nociceptive response to acute thermal stimuli in both normal and inflamed tissues. The heightened response to δ agonists in the hyperalgesia model suggests that δ opioid receptors in the brain are promising targets for the treatment of pain arising from chronic inflammation. PMID:10780972

  17. Bone Cell-autonomous Contribution of Type 2 Cannabinoid Receptor to Breast Cancer-induced Osteolysis*

    PubMed Central

    Sophocleous, Antonia; Marino, Silvia; Logan, John G.; Mollat, Patrick; Ralston, Stuart H.; Idris, Aymen I.

    2015-01-01

    The cannabinoid type 2 receptor (CB2) has previously been implicated as a regulator of tumor growth, bone remodeling, and bone pain. However, very little is known about the role of the skeletal CB2 receptor in the regulation of osteoblasts and osteoclasts changes associated with breast cancer. Here we found that the CB2-selective agonists HU308 and JWH133 reduced the viability of a variety of parental and bone-tropic human and mouse breast cancer cells at high micromolar concentrations. Under conditions in which these ligands are used at the nanomolar range, HU308 and JWH133 enhanced human and mouse breast cancer cell-induced osteoclastogenesis and exacerbated osteolysis, and these effects were attenuated in cultures obtained from CB2-deficient mice or in the presence of a CB2 receptor blocker. HU308 and JWH133 had no effects on osteoblast growth or differentiation in the presence of conditioned medium from breast cancer cells, but under these circumstances both agents enhanced parathyroid hormone-induced osteoblast differentiation and the ability to support osteoclast formation. Mechanistic studies in osteoclast precursors and osteoblasts showed that JWH133 and HU308 induced PI3K/AKT activity in a CB2-dependent manner, and these effects were enhanced in the presence of osteolytic and osteoblastic factors such as RANKL (receptor activator of NFκB ligand) and parathyroid hormone. When combined with published work, these findings suggest that breast cancer and bone cells exhibit differential responses to treatment with CB2 ligands depending upon cell type and concentration used. We, therefore, conclude that both CB2-selective activation and antagonism have potential efficacy in cancer-associated bone disease, but further studies are warranted and ongoing. PMID:26195631

  18. Bone Cell-autonomous Contribution of Type 2 Cannabinoid Receptor to Breast Cancer-induced Osteolysis.

    PubMed

    Sophocleous, Antonia; Marino, Silvia; Logan, John G; Mollat, Patrick; Ralston, Stuart H; Idris, Aymen I

    2015-09-04

    The cannabinoid type 2 receptor (CB2) has previously been implicated as a regulator of tumor growth, bone remodeling, and bone pain. However, very little is known about the role of the skeletal CB2 receptor in the regulation of osteoblasts and osteoclasts changes associated with breast cancer. Here we found that the CB2-selective agonists HU308 and JWH133 reduced the viability of a variety of parental and bone-tropic human and mouse breast cancer cells at high micromolar concentrations. Under conditions in which these ligands are used at the nanomolar range, HU308 and JWH133 enhanced human and mouse breast cancer cell-induced osteoclastogenesis and exacerbated osteolysis, and these effects were attenuated in cultures obtained from CB2-deficient mice or in the presence of a CB2 receptor blocker. HU308 and JWH133 had no effects on osteoblast growth or differentiation in the presence of conditioned medium from breast cancer cells, but under these circumstances both agents enhanced parathyroid hormone-induced osteoblast differentiation and the ability to support osteoclast formation. Mechanistic studies in osteoclast precursors and osteoblasts showed that JWH133 and HU308 induced PI3K/AKT activity in a CB2-dependent manner, and these effects were enhanced in the presence of osteolytic and osteoblastic factors such as RANKL (receptor activator of NFκB ligand) and parathyroid hormone. When combined with published work, these findings suggest that breast cancer and bone cells exhibit differential responses to treatment with CB2 ligands depending upon cell type and concentration used. We, therefore, conclude that both CB2-selective activation and antagonism have potential efficacy in cancer-associated bone disease, but further studies are warranted and ongoing. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Dopamine receptor agonists, partial agonists and psychostimulant addiction.

    PubMed

    Pulvirenti, L; Koob, G F

    1994-10-01

    Despite the epidemic growth of psychostimulant addiction over the past years, few pharmacological means of intervention are available to date for clinical treatment. This is of importance since the withdrawal syndrome that follows abstinence from drugs such as cocaine and the amphetamines is characterized, among other symptoms, by intense craving for the abused drug, and this is considered a critical factor leading into relapse of drug use. In this article, Luigi Pulvirenti and George Koob focus on the modulatory role shown by drugs acting at the dopamine receptor on the various phases of psychostimulant dependence in preclinical models and in human studies, and suggest that a class of compounds with partial agonist properties at the dopamine receptor may have therapeutic potential.

  20. Characterization of the complex morphinan derivative BU72 as a high efficacy, long-lasting mu-opioid receptor agonist.

    PubMed

    Neilan, Claire L; Husbands, Stephen M; Breeden, Simon; Ko, M C Holden; Aceto, Mario D; Lewis, John W; Woods, James H; Traynor, John R

    2004-09-19

    The development of buprenorphine as a treatment for opiate abuse and dependence has drawn attention to opioid ligands that have agonist actions followed by long-lasting antagonist actions. In a search for alternatives to buprenorphine, we discovered a bridged pyrrolidinomorphinan (BU72). In vitro, BU72 displayed high affinity and efficacy for mu-opioid receptors, but was also a partial delta-opioid receptor agonist and a full kappa-opioid receptor agonist. BU72 was a highly potent and long-lasting antinociceptive agent against both thermal and chemical nociception in the mouse and against thermal nociception in the monkey. These effects were prevented by mu-, but not kappa- or delta-, opioid receptor antagonists. Once the agonist effects of BU72 had subsided, the compound acted to attenuate the antinociceptive action of morphine. BU72 is too efficacious for human use but manipulation to reduce efficacy could provide a lead to the development of a treatment for opioid dependence.

  1. BRMS1 Suppresses Breast Cancer Metastasis to Bone via its Regulation of microRNA-125b and Downstream Attenuation of TNF-alpha and HER2 Signaling Pathways

    DTIC Science & Technology

    2012-10-01

    Stat3 translocated into nucleus of both vector and BRMS1- expressing cells at a similar rate (Fig. 3d ), suggesting that there may be another method of...capabilities to metastasize to ovaries, liver, lungs, kidneys, and bones following intravenous injection. We also observed skull -restricted bioluminescent... printing ” preformed by the institutional core facility confirmed that cell lines used exhibit properties of MDA- MB-231 cells consistent with ATCC profile

  2. Variable laser attenuator

    DOEpatents

    Foltyn, Stephen R.

    1988-01-01

    The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

  3. Variable laser attenuator

    DOEpatents

    Foltyn, S.R.

    1987-05-29

    The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

  4. Dopamine agonists for cocaine dependence.

    PubMed

    Soares, B G; Lima, M S; Reisser, A A; Farrell, M

    2001-01-01

    Cocaine is a major drug of abuse. Cocaine dependence is a common and serious condition, which has become nowadays a substantial public health problem. There is a wide and well documented range of consequences associated to chronic use of this drug, such as medical, psychological and social problems, including the spread of infectious diseases (e.g. AIDS, hepatitis and tuberculosis), crime, violence and neonatal drug exposure. Therapeutic management of the cocaine addicts includes an initial period of abstinence from the drug. During this phase the subjects may experience, besides the intense craving for cocaine, symptoms such as depression, fatigue, irritability, anorexia, and sleep disturbances. It was demonstrated that the acute use of cocaine may enhance dopamine transmission and chronically it decreases dopamine concentrations in the brain. Pharmacological treatment that affects dopamine could theoretically reduce these symptoms and contribute to a more successful therapeutic approach. To evaluate the efficacy and acceptability of dopamine agonists for treating cocaine dependence. We searched: The Cochrane Controlled Trials Register (Cochrane Library, issue 4, 2000), MEDLINE (from 1966 - 2000), EMBASE (from 1980 - 2000), LILACS (from 1982 - 2000), PsycLIT (from 1974 - 2000), Biological Abstracts (1982 to 2000). Reference searching; personal communication; conference abstracts; unpublished trials from pharmaceutical industry; book chapters on treatment of cocaine dependence. The inclusion criteria for all randomised controlled trials were that they should focus on the use of dopamine agonists on the treatment of cocaine dependence. Trials including patients with additional diagnosis such as opiate dependence were also eligible. The reviewers extracted the data independently and Relative Risks, weighted mean difference and number needed to treat were estimated. The reviewers assumed that people who died or dropped out had no improvement and tested the sensitivity

  5. Dopamine agonists for cocaine dependence.

    PubMed

    Soares, B G O; Lima, M S; Reisser, A A P; Farrell, M

    2003-01-01

    Cocaine dependence is a common and serious condition, which has become nowadays a substantial public health problem. There is a wide and well documented range of consequences associated to chronic use of this drug, such as medical, psychological and social problems, including the spread of infectious diseases (e.g. AIDS, hepatitis and tuberculosis), crime, violence and neonatal drug exposure. Therapeutic management of the cocaine addicts includes an initial period of abstinence from the drug. During this phase the subjects may experience, besides the intense craving for cocaine, symptoms such as depression, fatigue, irritability, anorexia, and sleep disturbances. It was demonstrated that the acute use of cocaine may enhance dopamine transmission and chronically it decreases dopamine concentrations in the brain. Pharmacological treatment that affects dopamine could theoretically reduce these symptoms and contribute to a more successful therapeutic approach. To evaluate the efficacy and acceptability of dopamine agonists for treating cocaine dependence. Electronic searches of Cochrane Library, EMBASE, MEDLINE, PsycLIT, Biological Abstracts and LILACS; reference searching; personal communication; conference abstracts; unpublished trials from pharmaceutical industry; book chapters on treatment of cocaine dependence, was performed for the primary version of this review in 2001. Another search of the electronic databases was done in December of 2002 for this update. The specialised register of trials of the Cochrane Group on Drugs and Alcohol was searched until February 2003. The inclusion criteria for all randomised controlled trials were that they should focus on the use of dopamine agonists on the treatment of cocaine dependence. The reviewers extracted the data independently and Relative Risks, weighted mean difference and number needed to treat were estimated. The reviewers assumed that people who died or dropped out had no improvement and tested the sensitivity of

  6. Microwave variable waveguide attenuator.

    PubMed

    Fabeni, P; Mugnai, D; Pazzi, G P; Ranfagni, A

    2008-06-01

    A new type of cutoff attenuator is presented. The attenuator works in the X-band in conditions of almost perfect matching. This means that the phase of the wave, which propagates inside the guide, does not suffer sensible variation in the passage between X- and K(u)-bands. Moreover, the attenuator works directly in the X-band, avoiding the passage between waveguide and cable, thus eliminating spurious effects due to this (double) passage. Experimental results of attenuation and dephasing using a prototype are also presented.

  7. PPARgamma agonists inhibit TGF-beta induced pulmonary myofibroblast differentiation and collagen production: implications for therapy of lung fibrosis.

    PubMed

    Burgess, Heather A; Daugherty, Louis Eugene; Thatcher, Thomas H; Lakatos, Heather F; Ray, Denise M; Redonnet, Michelle; Phipps, Richard P; Sime, Patricia J

    2005-06-01

    Pulmonary fibrosis is a progressive life-threatening disease for which no effective therapy exists. Myofibroblasts are one of the key effector cells in pulmonary fibrosis and are the primary source of extracellular matrix production. Drugs that inhibit the differentiation of fibroblasts to myofibroblasts have potential as antifibrotic therapies. Peroxisome proliferator-activated receptor (PPAR)-gamma is a transcription factor that upon ligation with PPARgamma agonists activates target genes containing PPAR response elements. PPARgamma agonists have anti-inflammatory activities and may have potential as antifibrotic agents. In this study, we examined the abilities of PPARgamma agonists to block two of the most important profibrotic activities of TGF-beta on pulmonary fibroblasts: myofibroblast differentiation and production of excess collagen. Both natural (15d-PGJ2) and synthetic (ciglitazone and rosiglitazone) PPARgamma agonists inhibited TGF-beta-driven myofibroblast differentiation, as determined by alpha-smooth muscle actin-specific immunocytochemistry and Western blot analysis. PPARgamma agonists also potently attenuated TGF-beta-driven type I collagen protein production. A dominant-negative PPARgamma partially reversed the inhibition of myofibroblast differentiation by 15d-PGJ2 and rosiglitazone, but the irreversible PPARgamma antagonist GW-9662 did not, suggesting that the antifibrotic effects of the PPARgamma agonists are mediated through both PPARgamma-dependent and independent mechanisms. Thus PPARgamma agonists have novel and potent antifibrotic effects in human lung fibroblasts and may have potential for therapy of fibrotic diseases in the lung and other tissues.

  8. Triptans attenuate circadian responses to light.

    PubMed

    Basu, Priyoneel; Ie, Naomi; Wensel, Adrienne L; Baskerville, Joelle D; Smith, Victoria M; Antle, Michael C

    2015-10-01

    Daily exposure to light synchronizes the circadian clock, located in the suprachiasmatic nucleus (SCN), to external day/night cycles. These responses to light can be modified by serotonergic drugs, such as serotonin 5HT1B receptor agonists. Triptans are specific 5HT1B agonists prescribed to treat migraines. Here, we examined the effects of two triptans (zolmitriptan and sumatriptan) on photic phase resetting in Syrian hamsters. Pre-treatment with intra-SCN sumatriptan significantly attenuates, and at higher doses completely blocks, phase advances to light during the late night. Pre-treatment with systemic zolmitriptan significantly attenuates both light-induced phase advances and phase delays. Neither of these drugs, nor their vehicles, causes phase shifts on their own. Pre-treatment with zolmitriptan also significantly reduces the expression of light-induced c-fos in the SCN. Neither zolmitriptan nor vehicle alone induces significant c-fos expression in the SCN. Finally, pre-treatment with zolmitriptan does not attenuate phase shifts to intra-SCN N-methyl-d-aspartate injections, indicating that the mechanism of action for zolmitriptan is likely to be through activation of presynaptic 5HT1B receptors on retinal terminals, thereby decreasing light-induced neurotransmitter release. As triptans are commercially available medications, there is potential for their use in blocking unwanted photic phase shifting during shift-work or jet-lag. Additionally, triptans may also affect the circadian clock in patients receiving them regularly for migraines. Finally, our results may hint at the mechanism by which triptans can alleviate the photophobia that frequently accompanies migraines, namely by activating 5HT1B receptors on retinal terminals elsewhere in the brain, and thereby diminishing visually-evoked neurotransmitter signalling in those areas.

  9. Beta-agonists and animal welfare

    USDA-ARS?s Scientific Manuscript database

    The use of beta-agonists in animal feed is a high profile topic within the U.S. as consumers and activist groups continue to question its safety. The only beta-agonist currently available for use in swine is ractopamine hydrochloride (RAC). This is available as Paylean™ (Elanco Animal Health – FDA a...

  10. Small Molecule Fluoride Toxicity Agonists

    PubMed Central

    Nelson1, James W.; Plummer, Mark S.; Blount, Kenneth F.; Ames, Tyler D.; Breaker, Ronald R.

    2015-01-01

    SUMMARY Fluoride is a ubiquitous anion that inhibits a wide variety of metabolic processes. Here we report the identification of a series of compounds that enhance fluoride toxicity in Escherichia coli and Streptococcus mutans. These molecules were isolated by using a high-throughput screen (HTS) for compounds that increase intracellular fluoride levels as determined via a fluoride riboswitch-reporter fusion construct. A series of derivatives were synthesized to examine structure-activity relationships, leading to the identification of compounds with improved activity. Thus, we demonstrate that small molecule fluoride toxicity agonists can be identified by HTS from existing chemical libraries by exploiting a natural fluoride riboswitch. In addition, our findings suggest that some molecules might be further optimized to function as binary antibacterial agents when combined with fluoride. PMID:25910244

  11. Small molecule fluoride toxicity agonists.

    PubMed

    Nelson, James W; Plummer, Mark S; Blount, Kenneth F; Ames, Tyler D; Breaker, Ronald R

    2015-04-23

    Fluoride is a ubiquitous anion that inhibits a wide variety of metabolic processes. Here, we report the identification of a series of compounds that enhance fluoride toxicity in Escherichia coli and Streptococcus mutans. These molecules were isolated by using a high-throughput screen (HTS) for compounds that increase intracellular fluoride levels as determined via a fluoride riboswitch reporter fusion construct. A series of derivatives were synthesized to examine structure-activity relationships, leading to the identification of compounds with improved activity. Thus, we demonstrate that small molecule fluoride toxicity agonists can be identified by HTS from existing chemical libraries by exploiting a natural fluoride riboswitch. In addition, our findings suggest that some molecules might be further optimized to function as binary antibacterial agents when combined with fluoride.

  12. Bone marrow aspiration

    MedlinePlus

    Iliac crest tap; Sternal tap; Leukemia - bone marrow aspiration; Aplastic anemia - bone marrow aspiration; Myelodysplastic syndrome - bone marrow aspiration; Thrombocytopenia - bone marrow aspiration; Myelofibrosis - bone marrow aspiration

  13. GABAergic involvement in motor effects of an adenosine A(2A) receptor agonist in mice.

    PubMed

    Khisti, R T; Chopde, C T; Abraham, E

    2000-04-03

    Adenosine A(2A) agonists are known to induce catalepsy and inhibit dopamine mediated motor hyperactivity. An antagonistic interaction between adenosine A(2A) and dopamine D(2) receptors is known to regulate GABA-mediated neurotransmission in striatopallidal neurons. Stimulation of adenosine A(2A) and dopamine D(2) receptors has been shown to increase and inhibit GABA release respectively in pallidal GABAergic neurons. However, the role of GABAergic neurotransmission in the motor effects of adenosine A(2A) receptors is not yet known. Therefore in the present study the effect of GABAergic agents on adenosine A(2A) receptor agonist (NECA- or CGS 21680) induced catalepsy and inhibition of amphetamine elicited motor hyperactivity was examined. Pretreatment with GABA, the GABA(A) agonist muscimol or the GABA(B) agonist baclofen potentiated whereas the GABA(A) antagonist bicuculline attenuated NECA- or CGS 21680-induced catalepsy. However, the GABA(B) antagonists phaclophen and delta-aminovaleric acid had no effect. Administration of NECA or CGS 21680 not only reduced spontaneous locomotor activity but also antagonized amphetamine elicited motor hyperactivity. These effects of NECA and CGS 21680 were potentiated by GABA or muscimol and antagonized by bicuculline. These findings provide behavioral evidence for the role of GABA in the motor effects of adenosine A(2A) receptor agonists. Activation of adenosine A(2A) receptors increases GABA release which could reduce dopaminergic tone and induce catalepsy or inhibit amphetamine mediated motor hyperactivity.

  14. Locomotion induced by ventral tegmental microinjections of a nicotinic agonist.

    PubMed

    Museo, E; Wise, R A

    1990-03-01

    Bilateral microinjections of the nicotinic agonist cytisine (0.1, 1 or 10 nanomoles per side) into the ventral tegmental area increased locomotor activity. This increase in locomotion was antagonized by mecamylamine (2 mg/kg, IP), a nicotinic antagonist that readily crosses the blood-brain barrier, and by pimozide (0.3 mg/kg, IP), a central dopaminergic antagonist. Hexamethonium (2 mg/kg, IP), a nicotinic antagonist that, unlike mecamylamine, does not cross the blood-brain barrier, had no effect; this suggests that mecamylamine's attenuation of cytisine-induced locomotor activity resulted from a blockade of central and not peripheral nicotinic receptors. The data support the notion that nicotinic and dopaminergic substrates interact at the level of the VTA to produce increases in locomotor activity.

  15. α(2) Adrenergic and imidazoline receptor agonists prevent cue-induced cocaine seeking.

    PubMed

    Smith, Rachel J; Aston-Jones, Gary

    2011-10-15

    Drug-associated cues can elicit stress-like responses in addicted individuals, indicating that cue- and stress-induced drug relapse may share some neural mechanisms. It is unknown whether α(2) adrenergic receptor agonists, which are known to attenuate stress-induced reinstatement of drug seeking in rats, also reduce cue-induced reinstatement. Rats were tested for reinstatement of drug seeking following cocaine self-administration and extinction. We first evaluated the effects of clonidine, an agonist at α(2) and imidazoline-1 (I(1)) receptors, on relapse to cocaine seeking. To explore possible mechanisms of clonidine's effects, we then tested more specific α(2) or I(1) agonists, postsynaptic adrenergic receptor (α(1) and β) antagonists, and corticotropin-releasing factor receptor-1 antagonists. We found that clonidine, and the more selective α(2) agonists UK-14,304 and guanfacine, decreased cue-induced reinstatement of cocaine seeking. The specific I(1) receptor agonist moxonidine reduced cue-induced as well as cocaine-induced reinstatement. Clonidine or moxonidine effects on cue-induced reinstatement were reversed by the selective α(2) receptor antagonist RS-79948, indicating a role for α(2) receptors. Prazosin and propranolol, antagonists at the α(1) and β receptor, respectively, reduced cue-induced reinstatement only when administered in combination. Finally, the corticotropin-releasing factor receptor-1 antagonist CP-154,526 reduced cue-induced reinstatement, as previously observed for stress-induced reinstatement, indicating possible overlap between stress and cue mechanisms. These results indicate that α(2) and I(1) receptor agonists are novel therapeutic options for prevention of cue-induced cocaine relapse. Given that α(2) receptor stimulation is associated with sedation in humans, the I(1) agonist moxonidine seems to have substantial potential for treating addictive disorders. Copyright © 2011 Society of Biological Psychiatry. Published by

  16. Biased signaling by peptide agonists of protease activated receptor 2.

    PubMed

    Jiang, Yuhong; Yau, Mei-Kwan; Kok, W Mei; Lim, Junxian; Wu, Kai-Chen; Liu, Ligong; Hill, Timothy A; Suen, Jacky Y; Fairlie, David P

    2017-02-07

    Protease activated receptor 2 (PAR2) is associated with metabolism, obesity, inflammatory, respiratory and gastrointestinal disorders, pain, cancer and other diseases. The extracellular N-terminus of PAR2 is a common target for multiple proteases, which cleave it at different sites to generate different N-termini that activate different PAR2-mediated intracellular signaling pathways. There are no synthetic PAR2 ligands that reproduce the same signaling profiles and potencies as proteases. Structure-activity relationships here for 26 compounds spanned a signaling bias over 3 log units, culminating in three small ligands as biased agonist tools for interrogating PAR2 functions. DF253 (2f-LAAAAI-NH2) triggered PAR2-mediated calcium release (EC50 2 μM) but not ERK1/2 phosphorylation (EC50 > 100 μM) in CHO cells transfected with hPAR2. AY77 (Isox-Cha-Chg-NH2) was a more potent calcium-biased agonist (EC50 40 nM, Ca2+; EC50 2 μM, ERK1/2), while its analogue AY254 (Isox-Cha-Chg-A-R-NH2) was an ERK-biased agonist (EC50 2 nM, ERK1/2; EC50 80 nM, Ca2+). Signaling bias led to different functional responses in human colorectal carcinoma cells (HT29). AY254, but not AY77 or DF253, attenuated cytokine-induced caspase 3/8 activation, promoted scratch-wound healing and induced IL-8 secretion, all via PAR2-ERK1/2 signaling. Different ligand components were responsible for different PAR2 signaling and functions, clues that can potentially lead to drugs that modulate different pathway-selective cellular and physiological responses.

  17. Investigation of the use of X-ray CT images for attenuation compensation in SPECT

    SciTech Connect

    LaCroix, K.J.; Tsui, B.M.W. ); Hasegawa, B.H.; Brown, J.K. )

    1994-12-01

    This study investigates the general use of single-beam X-ray computed tomography (CT) images for generating attenuation maps for compensation of photon attenuation in SPECT images. A 3D mathematical thorax phantom is used to simulate both emission and transmission projection data for monoenergetic and polyenergetic sources. Polyenergetic transmission projection data are simulated for a standard X-ray spectrum and fan-beam geometry. The projection data are reconstructed using filtered backprojection to form an X-ray CT image which is then scaled to produce an estimate of the attenuation map at the energy of the emission radionuclide. Emission projection data are simulated for a fan-beam geometry at the energies of [sup 201]Tl and [sup 99m]Tc, two radionuclides commonly used in cardiac SPECT. Detector response and scatter are not included in the model. Noiseless, emission projection data are iteratively reconstructed using the ML-EM algorithm with nonuniform attenuation compensation and attenuation maps derived from both the simulated X-ray CT image and from a simulated monoenergetic transmission CT image. The attenuation maps generated from the X-ray CT images accurately estimate the attenuation coefficient for muscle and lung tissues, but not for bone tissues, which show error in the attenuation coefficient of 21--42% for spinal bone and 34--58% for rib bone. However, despite the inaccurate estimate of bone attenuation, the reconstructed SPECT images provide estimates of myocardial radioactivity concentration to within 9% and show few artifacts.

  18. Selective VIP Receptor Agonists Facilitate Immune Transformation for Dopaminergic Neuroprotection in MPTP-Intoxicated Mice

    PubMed Central

    Olson, Katherine E.; Kosloski-Bilek, Lisa M.; Anderson, Kristi M.; Diggs, Breha J.; Clark, Barbara E.; Gledhill, John M.; Shandler, Scott J.; Mosley, R. Lee

    2015-01-01

    Vasoactive intestinal peptide (VIP) mediates a broad range of biological responses by activating two related receptors, VIP receptor 1 and 2 (VIPR1 and VIPR2). Although the use of native VIP facilitates neuroprotection, clinical application of the hormone is limited due to VIP's rapid metabolism and inability to distinguish between VIPR1 and VIPR2 receptors. In addition, activation of both receptors by therapeutics may increase adverse secondary toxicities. Therefore, we developed metabolically stable and receptor-selective agonists for VIPR1 and VIPR2 to improve pharmacokinetic and pharmacodynamic therapeutic end points. Selective agonists were investigated for their abilities to protect mice against MPTP-induced neurodegeneration used to model Parkinson's disease (PD). Survival of tyrosine hydroxylase neurons in the substantia nigra was determined by stereological tests after MPTP intoxication in mice pretreated with either VIPR1 or VIPR2 agonist or after adoptive transfer of splenic cell populations from agonist-treated mice administered to MPTP-intoxicated animals. Treatment with VIPR2 agonist or splenocytes from agonist-treated mice resulted in increased neuronal sparing. Immunohistochemical tests showed that agonist-treated mice displayed reductions in microglial responses, with the most pronounced effects in VIPR2 agonist-treated, MPTP-intoxicated mice. In parallel studies, we observed reductions in proinflammatory cytokine release that included IL-17A, IL-6, and IFN-γ and increases in GM-CSF transcripts in CD4+ T cells recovered from VIPR2 agonist-treated animals. Moreover, a phenotypic shift of effector to regulatory T cells was observed. These results support the use of VIPR2-selective agonists as neuroprotective agents for PD treatment. SIGNIFICANCE STATEMENT Vasoactive intestinal peptide receptor 2 can elicit immune transformation in a model of Parkinson's disease (PD). Such immunomodulatory capabilities can lead to neuroprotection by attenuating

  19. Bone Fracture Exacerbates Murine Ischemic Cerebral Injury

    PubMed Central

    Degos, Vincent; Maze, Mervyn; Vacas, Susana; Hirsch, Jan; Guo, Yi; Shen, Fanxia; Jun, Kristine; van Rooijen, Nico; Gressens, Pierre; Young, William L.; Su, Hua

    2014-01-01

    Background Bone fracture increases alarmins and pro-inflammatory cytokines in the blood, and provokes macrophage infiltration and pro-inflammatory cytokine expression in the hippocampus. We recently reported that stroke is an independent risk factor after bone surgery for adverse outcome, the impact of bone fracture on stroke outcome is unknown. We tested the hypothesis that bone fracture, shortly after ischemic stroke, enhances stroke-related injuries by augmenting the neuroinflammatory response. Methods Tibia fracture (bone fracture) was induced in mice one day after permanent occlusion of the distal middle cerebral artery (stroke). High-mobility-group box chromosomal protein-1 (HMGB1) was tested to mimic the bone fracture effects. HMGB1 neutralizing antibody and clodrolip (macrophage depletion) were tested to attenuate the bone fracture effects. Neurobehavioral function (n=10), infarct volume, neuronal death, and macrophages/microglia-infiltration (n=6–7) were analyzed three days after. Results We found that mice with both stroke and bone fracture had larger infarct volumes (mean percentage of ipsilateral hemisphere±SD: 30±7% vs. 12±3%, n=6, P<0.001) more severe neurobehavioral dysfunction, and more macrophages/microglia in the peri-infarct region than mice with stroke only. Intraperitoneal injection of HMGB1 mimicked, whereas neutralizing HMGB1 attenuated, the bone fracture effects and the macrophage/microglia infiltration. Depleting macrophages with clodrolip also attenuated the aggravating effects of bone fracture on stroke lesion and behavioral dysfunction. Conclusions These novel findings suggest that bone fracture shortly after stroke enhances stroke injury via augmented inflammation through HMGB1 and macrophage/microglia infiltration. Interventions to modulate early macrophage/microglia activation could be therapeutic goals to limit the adverse consequences of bone fracture after stroke. PMID:23438676

  20. Bone tumor

    MedlinePlus

    ... primary bone tumors include: Chondrosarcoma Ewing sarcoma Fibrosarcoma Osteosarcomas Cancers that most often spread to the bone are cancers of the: Breast Kidney Lung Prostate Thyroid These forms of cancer usually affect ...

  1. Bone grafts.

    PubMed

    Hubble, Matthew J W

    2002-09-01

    Bone grafts are used in musculoskeletal surgery to restore structural integrity and enhance osteogenic potential. The demand for bone graft for skeletal reconstruction in bone tumor, revision arthroplasty, and trauma surgery, couple with recent advances in understanding and application of the biology of bone transplantation, has resulted in an exponential increase in the number of bone-grafting procedures performed over the last decade. It is estimated that 1.5 million bone-grafting procedures are currently performed worldwide each year, compared to a fraction of that number 20 years ago. Major developments also have resulted in the harvesting, storage, and use of bone grafts and production of graft derivatives, substitutes, and bone-inducing agents.

  2. Identification of oligomer proanthocyanidins (F2) isolated from grape seeds as a formyl peptide receptor 1 partial agonist.

    PubMed

    Yang, Jingyu; Wang, Qing; Zhao, Ruijun; Sun, Baoshan; Wang, Lihui; Hou, Yue; Li, Xiaoqin; Wu, Chunfu

    2013-04-01

    Formyl peptide receptor 1 (FPR1) plays an important role in the rapid progression of glioblastoma and has been considered as a molecular target for the treatment. Previously, we have shown that oligomer proanthocyanidins (F2, degree of polymerization 2-15), isolated from grape seeds, inhibited FPR1-mediated chemotaxis of U-87 glioblastoma cells. In the present study, we investigated the capacity of F2 to interact with FPR1. The cross attenuation of chemotaxis revealed that F2 shared FPR1 with formyl-methionyl-leucyl-phenylalanine (fMLF), which is a prototype agonist of FPR1. F2 was chemotactic for U-87 cells, and the chemotactic response was abolished when FPR1 gene was silenced or FPR1 was competitively occupied. We further show that F2 specifically blocked the binding of fluorescent agonist to FPR1. Interestingly, F2 exhibited the characteristic of a partial agonist for FPR1, as shown by its capacity to activate FPR1-mediated PI3K-PKC-MAPK pathways. Meanwhile, F2 also attenuated fMLF-triggered MAPK activation, suggesting that F2 could antagonize the effect of an agonist. Furthermore, F2 abolished the invasion of U-87 cells induced by fMLF. Thus, we have identified F2 as a novel, partial agonist for FPR1, which may be useful for glioblastoma therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. [Bone disease in Gaucher's disease].

    PubMed

    Roca Espiau, Mercedes

    2011-09-01

    The exposition aims, is to review the pathophysiological mechanisms of bone marrow involvement and the patterns of marrow infiltration by Gaucher cells. We have reviewed the different methods of assessment of bone marrow infiltration and its temporal development. Qualitative methods include simple radiography, magnetic resonance imaging (MRI), computed tomography (CT) and radioisotope. The simple radiography is the basic element, but its sensitivity is limited and only allows for assessing changes and trabecular bone remodeling MRI allows us to appreciate the bone marrow infiltration, detection of complications and response to therapy. Radioisotopes can contribute to the differential diagnosis of osteomyelitis and bone crises. Among the quantitative methods are the QCSI (quantitative chemical shift imaging) and the dual-energy X-ray absorptiometry (DEXA), as well as new quantitative techniques of CT, MRI and ultrasound densitometry. The QCSI performed an assessment of fat content of bone marrow in the spine. DEXA quantifies bone density by measuring the attenuation coefficient. The semiquantitative methods have various "scores" to establish criteria for generalized bone disease endpoints of disease progression and response to therapy.

  4. Bone Analyzer

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The danger of disuse osteoporosis under weightless condition in space led to extensive research into measurements of bone stiffness and mass by the Biomedical Research Division of Ames and Stanford University. Through its Technology Utilization Program, NASA funded an advanced SOBSA, a microprocessor-controlled bone probe system. SOBSA determines bone stiffness by measuring responses to an electromagnetic shaker. With this information, a physician can identify bone disease, measure deterioration and prescribe necessary therapy. The system is now undergoing further testing.

  5. Bone cement

    PubMed Central

    Vaishya, Raju; Chauhan, Mayank; Vaish, Abhishek

    2013-01-01

    The knowledge about the bone cement is of paramount importance to all Orthopaedic surgeons. Although the bone cement had been the gold standard in the field of joint replacement surgery, its use has somewhat decreased because of the advent of press-fit implants which encourages bone in growth. The shortcomings, side effects and toxicity of the bone cement are being addressed recently. More research is needed and continues in the field of nanoparticle additives, enhanced bone–cement interface etc. PMID:26403875

  6. Transforming growth factor-β1 and cigarette smoke inhibit the ability of β2-agonists to enhance epithelial permeability.

    PubMed

    Unwalla, Hoshang J; Ivonnet, Pedro; Dennis, John S; Conner, Gregory E; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl(-) and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist-mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air-liquid interface, were used for (14)C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist-mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist-mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist-mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in disease

  7. Investigation of the mechanism of agonist and inverse agonist action at D2 dopamine receptors.

    PubMed

    Roberts, David J; Lin, Hong; Strange, Philip G

    2004-05-01

    This study investigated, for the D2 dopamine receptor, the relation between the ability of agonists and inverse agonists to stabilise different states of the receptor and their relative efficacies. Ki values for agonists were determined in competition versus the binding of the antagonist [3H]spiperone. Competition data were fitted best by a two-binding site model (with the exception of bromocriptine, for which a one-binding site model provided the best fit) and agonist affinities for the higher (Kh) (G protein-coupled) and lower affinity (Kl) (G protein-uncoupled) sites determined. Ki values for agonists were also determined in competition versus the binding of the agonist [3H]N-propylnorapomorphine (NPA) to provide a second estimate of Kh. Maximal agonist effects (Emax) and their potencies (EC50) were determined from concentration-response curves for agonist stimulation of guanosine-5'-O-(3-[32S]thiotriphosphate) ([35S]GTPgammaS) binding. The ability of agonists to stabilise the G protein-coupled state of the receptor (Kl/Kh determined from ligand-binding assays) did not correlate with either of two measures of relative efficacy (relative Emax, Kl/EC50) of agonists determined in [35S]GTPgammaS-binding assays, when the data for all of the compounds tested were analysed. For a subset of compounds, however, there was a relation between Kl/Kh and Emax. Competition-binding data versus [3H]spiperone and [3H]NPA for a range of inverse agonists were fitted best by a one-binding site model. Ki values for the inverse agonists tested were slightly lower in competition versus [3H]NPA compared to [3H]spiperone. These data do not provide support for the idea that inverse agonists act by binding preferentially to the ground state of the receptor.

  8. Bone Infections

    MedlinePlus

    ... bloodstream. People who are at risk for bone infections include those with diabetes, poor circulation, or recent injury to the bone. You may also be at risk if you are having hemodialysis. Symptoms of bone infections include Pain in the infected area Chills and ...

  9. Development and Characterization of Pepducins as Gs-biased Allosteric Agonists*♦

    PubMed Central

    Carr, Richard; Du, Yang; Quoyer, Julie; Panettieri, Reynold A.; Janz, Jay M.; Bouvier, Michel; Kobilka, Brian K.; Benovic, Jeffrey L.

    2014-01-01

    The β2-adrenergic receptor (β2AR) is a prototypical G protein-coupled receptor that mediates many hormonal responses, including cardiovascular and pulmonary function. β-Agonists used to combat hypercontractility in airway smooth muscle stimulate β2AR-dependent cAMP production that ultimately promotes airway relaxation. Chronic stimulation of the β2AR by long acting β-agonists used in the treatment of asthma can promote attenuated responsiveness to agonists and an increased frequency of fatal asthmatic attacks. β2AR desensitization to β-agonists is primarily mediated by G protein-coupled receptor kinases and β-arrestins that attenuate receptor-Gs coupling and promote β2AR internalization and degradation. A biased agonist that can selectively stimulate Gs signaling without promoting receptor interaction with G protein-coupled receptor kinases and β-arrestins should serve as an advantageous asthma therapeutic. To identify such molecules, we screened ∼50 lipidated peptides derived from the intracellular loops of the β2AR, known as pepducins. This screen revealed two classes of Gs-biased pepducins, receptor-independent and receptor-dependent, as well as several β-arrestin-biased pepducins. The receptor-independent Gs-biased pepducins operate by directly stimulating G protein activation. In contrast, receptor-dependent Gs-biased pepducins appear to stabilize a Gs-biased conformation of the β2AR that couples to Gs but does not undergo G protein-coupled receptor kinase-mediated phosphorylation or β-arrestin-mediated internalization. Functional studies in primary human airway smooth muscle cells demonstrate that Gs-biased pepducins are not subject to conventional desensitization and thus may be good candidates for the development of next generation asthma therapeutics. Our study reports the first Gs-biased activator of the β2AR and provides valuable tools for the study of β2AR function. PMID:25395624

  10. Tyrphostin analogs are GPR35 agonists.

    PubMed

    Deng, Huayun; Hu, Haibei; Fang, Ye

    2011-06-23

    GPR35 is an orphan G protein-coupled receptor that is not well-characterized. Here we employ dynamic mass redistribution (DMR) assays to discover new GPR35 agonists. DMR assays identified tyrphostin analogs as GPR35 agonists, which were confirmed with receptor internalization, Tango β-arrestin translocation, and extracellular-signal-regulated kinase phosphorylation assays. These agonists provide pharmacological tools to study the biology and function of GPR35. Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  11. Aspirin metabolites are GPR35 agonists.

    PubMed

    Deng, Huayun; Fang, Ye

    2012-07-01

    Aspirin is widely used as an anti-inflammatory, anti-platelet, anti-pyretic, and cancer-preventive agent; however, the molecular mode of action is unlikely due entirely to the inhibition of cyclooxygenases. Here, we report the agonist activity of several aspirin metabolites at GPR35, a poorly characterized orphan G protein-coupled receptor. 2,3,5-Trihydroxybenzoic acid, an aspirin catabolite, was found to be the most potent GPR35 agonist among aspirin metabolites. Salicyluric acid, the main metabolite of aspirin, was also active. These results suggest that the GPR35 agonist activity of certain aspirin metabolites may contribute to the clinical features of aspirin.

  12. Design of anticancer lysophosphatidic acid agonists and antagonists.

    PubMed

    Parrill, Abby L

    2014-05-01

    Lysophosphatidic acid (LPA) and its receptors, LPA1-6, are integral parts of signaling pathways involved in cellular proliferation, migration and survival. These signaling pathways are of therapeutic interest for the treatment of multiple types of cancer and to reduce cancer metastasis and side effects. Validated therapeutic potential of key receptors, as well as recent structure-activity relationships yielding compounds with low nanomolar potencies are exciting recent advances in the field. Some compounds have proven efficacious in vivo against tumor proliferation and metastasis, bone cancer pain and the pulmonary fibrosis that can result as a side effect of pulmonary cancer radiation treatment. However, recent studies have identified that LPA contributes through multiple pathways to the development of chemotherapeutic resistance suggesting new applications for LPA antagonists in cancer treatment. This review summarizes the roles of LPA signaling in cancer pathophysiology and recent progress in the design and evaluation of LPA agonists and antagonists.

  13. Bone Densitometry (Bone Density Scan)

    MedlinePlus

    ... In some communities, a CT scan with special software can also be used to diagnose or monitor ... patient's bone mineral density. DEXA machines feature special software that compute and display the bone density measurements ...

  14. RADIO FREQUENCY ATTENUATOR

    DOEpatents

    Giordano, S.

    1963-11-12

    A high peak power level r-f attenuator that is readily and easily insertable along a coaxial cable having an inner conductor and an outer annular conductor without breaking the ends thereof is presented. Spaced first and second flares in the outer conductor face each other with a slidable cylindrical outer conductor portion therebetween. Dielectric means, such as water, contact the cable between the flares to attenuate the radio-frequency energy received thereby. The cylindrical outer conductor portion is slidable to adjust the voltage standing wave ratio to a low level, and one of the flares is slidable to adjust the attenuation level. An integral dielectric container is also provided. (AFC)

  15. Landing gear noise attenuation

    NASA Technical Reports Server (NTRS)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  16. Compensation for non-uniform attenuation in SPECT brain imaging

    SciTech Connect

    Glick, S.J.; King, M.A.; Pan, T.S.

    1994-05-01

    Photon attenuation is a major limitation in performing quantitative SPECT brain imaging. A number of methods have been proposed for compensation of attenuation in regions of the body that can be modelled as a uniform attenuator. The magnitude of the errors introduced into reconstructed brain images by assuming the head to be a uniform attenuator are uncertain (the skull, sinus cavities and head holder all have different attenuation properties than brain tissue). Brain imaging is unique in that the radioisotope, for the most part, is taken up within a uniform attenuation medium (i.e., brain tissue) which is surrounded by bone (i.e., the skull) of a different density. Using this observation, Bellini`s method for attenuation compensation (which is an exact solution to the exponential Radon transform) has been modified to account for the different attenuation properties of the skull. To test this modified Bellini method, a simple mathematical phantom was designed to model the brain and a skull of varying thickness less than 7.5 mm. To model brain imaging with Tc-99m HMPAO, the attenuation coefficient of the brain tissue and skull were set to 0.15 cm{sup -1} and 0.22 cm{sup -1} respectively. A ray-driven projector which accounted for non-uniform attenuation was used to simulate projection data from 128 views. The detector response and scatter were not simulated. It was observed that reconstructions processed with uniform attenuation compensation (i.e., where it was assumed that the brain tissue and the skull had the same attenuation coefficient) provided errors of 6-20%, whereas those processed with the non-uniform Bellini algorithm were biased by only 0-5%.

  17. Differential activation of the μ-opioid receptor by oxycodone and morphine in pain-related brain regions in a bone cancer pain model

    PubMed Central

    Nakamura, Atsushi; Hasegawa, Minoru; Minami, Kazuhisa; Kanbara, Tomoe; Tomii, Takako; Nishiyori, Atsushi; Narita, Minoru; Suzuki, Tsutomu; Kato, Akira

    2013-01-01

    Background and Purpose Bone cancer pain is chronic and often difficult to control with opioids. However, recent studies have shown that several opioids have distinct analgesic profiles in chronic pain. Experimental Approach To clarify the mechanisms underlying these distinct analgesic profiles, functional changes in the μ-opioid receptor were examined using a mouse femur bone cancer (FBC) model. Key Results In the FBC model, the Bmax of [3H]-DAMGO binding was reduced by 15–45% in the periaqueductal grey matter (PAG), region ventral to the PAG (vPAG), mediodorsal thalamus (mTH), ventral thalamus and spinal cord. Oxycodone (10−8–10−5 M) and morphine (10−8–10−5 M) activated [35S]-GTPγS binding, but the activation was significantly attenuated in the PAG, vPAG, mTH and spinal cord in the FBC model. Interestingly, the attenuation of oxycodone-induced [35S]-GTPγS binding was quite limited (9–26%) in comparison with that of morphine (46–65%) in the PAG, vPAG and mTH, but not in the spinal cord. Furthermore, i.c.v. oxycodone at doses of 0.02–1.0 μg per mouse clearly inhibited pain-related behaviours, such as guarding, limb-use abnormalities and allodynia-like behaviour in the FBC model mice, while i.c.v. morphine (0.05–2.0 μg per mouse) had only partial or little analgesic effect on limb-use abnormalities and allodynia-like behaviour. Conclusion and Implications These results show that μ-opioid receptor functions are attenuated in several pain-related regions in bone cancer in an agonist-dependent manner, and suggest that modification of the μ-opioid receptor is responsible for the distinct analgesic effect of oxycodone and morphine. PMID:22889192

  18. Correlations of linear and nonlinear ultrasound parameters with density and microarchitectural parameters in trabecular bone.

    PubMed

    Lee, Kang Il

    2013-11-01

    In the present study, correlations of linear and nonlinear ultrasound parameters (speed of sound, normalized broadband ultrasound attenuation, and nonlinear parameter B/A) with bone mineral density and microarchitectural parameters were investigated in 28 bovine femoral trabecular bone samples in vitro. All three ultrasound parameters exhibited relatively high correlation coefficients with the indexes of bone quantity (bone mineral density and bone volume fraction) and lower correlation coefficients with the remaining microarchitectural parameters. These results suggest that B/A, in addition to speed of sound and attenuation, may have potential as an index for the assessment of bone status and osteoporosis.

  19. Bone poroelasticity.

    PubMed

    Cowin, S C

    1999-03-01

    Poroelasticity is a well-developed theory for the interaction of fluid and solid phases of a fluid-saturated porous medium. It is widely used in geomechanics and has been applied to bone by many authors in the last 30 years. The purpose of this work is, first, to review the literature related to the application of poroelasticity to the interstitial bone fluid and, second, to describe the specific physical and modeling considerations that establish poroelasticity as an effective and useful model for deformation-driven bone fluid movement in bone tissue. The application of poroelasticity to bone differs from its application to soft tissues in two important ways. First, the deformations of bone are small while those of soft tissues are generally large. Second, the bulk modulus of the mineralized bone matrix is about six times stiffer than that of the fluid in the pores while the bulk moduli of the soft tissue matrix and the pore water are almost the same. Poroelasticity and electrokinetics can be used to explain strain-generated potentials in wet bone. It is noted that strain-generated potentials can be used as an effective tool in the experimental study of local bone fluid flow, and that the knowledge of this technique will contribute to the answers of a number of questions concerning bone mineralization, osteocyte nutrition and the bone mechanosensory system.

  20. [Bone substitutes].

    PubMed

    Jordana, Fabienne; Le Visage, Catherine; Weiss, Pierre

    2017-01-01

    Bone substitutes, used to fill a defect after a surgery or a trauma, provide a mechanical support and might induce bone healing. They constitute an alternative to autogenous bone grafts, the 'gold standard' which remains the reference despite its risk of postoperative complications. The clinician choice of a bone substitute is based on the required bone volume, the handling (injectability, malleability) and mechanical properties (setting time, viscosity, resorbability among others) of the material. Bone substitutes are commonly used in orthopedic surgery, neurosurgery, stomatology and dental applications. Their use increases steadily, with the recent clinical development of injectable forms. In addition, novel technologies by subtractive or additive techniques allow today the production of controlled architecture materials. Here, we present a bone substitutes classification according to their origin (natural or synthetic) and chemical composition, and the most common use of these substitutes. © 2017 médecine/sciences – Inserm.

  1. [Safety of beta-agonists in asthma].

    PubMed

    Oscanoa, Teodoro J

    2014-01-01

    Beta 2 agonist bronchodilators (β2A) are very important part in the pharmacotherapy of bronchial asthma, a disease that progresses in the world in an epidemic way. The β2A are prescribed to millions of people around the world, therefore the safety aspects is of public interest. Short-Acting β2 Agonists (SABAs), such as albuterol inhaler, according to current evidence, confirming its safety when used as a quick-relief or rescue medication. The long-acting β2 agonists (LABAs) The long-acting bronchodilators β2A (Long acting β2 Agonists or LABAs) are used associated with inhaled corticosteroids as controller drugs for asthma exacerbationsaccess, for safety reasons LABAs are not recommended for use as monotherapy.

  2. Glutamatergic contributions to nicotinic acetylcholine receptor agonist-evoked cholinergic transients in the prefrontal cortex.

    PubMed

    Parikh, Vinay; Man, Kingson; Decker, Michael W; Sarter, Martin

    2008-04-02

    Because modulation of cortical cholinergic neurotransmission has been hypothesized to represent a necessary mechanism mediating the beneficial cognitive effects of nicotine and nicotinic acetylcholine receptor (nAChR) subtype-selective agonists, we used choline-sensitive microelectrodes for the real-time measurement of ACh release in vivo, to characterize cholinergic transients evoked by nicotine and the alpha4beta2*-selective nAChR partial agonist 2-methyl-3-(2-(S)-pyrrolindinylmethoxy)pyridine dihydrochloride (ABT-089), a clinically effective cognition enhancer. In terms of cholinergic signal amplitudes, ABT-089 was significantly more potent than nicotine in evoking ACh cholinergic transients. Moreover, cholinergic signals evoked by ABT-089 were characterized by faster signal rise time and decay rate. The nAChR antagonist mecamylamine attenuated the cholinergic signals evoked by either compound. Cholinergic signals evoked by ABT-089 were more efficaciously attenuated by the relatively beta2*-selective nAChR antagonist dihydro-beta-erythroidine. The alpha7 antagonist methyllycaconitine did not affect choline signal amplitudes but partly attenuated the relatively slow decay rate of nicotine-evoked cholinergic signals. Furthermore, the AMPA receptor antagonist DNQX as well as the NMDA receptor antagonist APV more potently attenuated cholinergic signals evoked by ABT-089. Using glutamate-sensitive microelectrodes to measure glutamatergic transients, ABT-089 was more potent than nicotine in evoking glutamate release. Glutamatergic signals were highly sensitive to tetrodotoxin-induced blockade of voltage-regulated sodium channels. Together, the present evidence indicates that compared with nicotine, ABT-089 evokes more potent and sharper cholinergic transients in prefrontal cortex. Glutamatergic mechanisms necessarily mediate the cholinergic effects of nAChR agonists in the prefrontal cortex.

  3. Negative cooperativity in binding of muscarinic receptor agonists and GDP as a measure of agonist efficacy

    PubMed Central

    Jakubík, J; Janíčková, H; El-Fakahany, EE; Doležal, V

    2011-01-01

    BACKGROUND AND PURPOSE Conventional determination of agonist efficacy at G-protein coupled receptors is measured by stimulation of guanosine-5′-γ−thiotriphosphate (GTPγS) binding. We analysed the role of guanosine diphosphate (GDP) in the process of activation of the M2 muscarinic acetylcholine receptor and provide evidence that negative cooperativity between agonist and GDP binding is an alternative measure of agonist efficacy. EXPERIMENTAL APPROACH Filtration and scintillation proximity assays measured equilibrium binding as well as binding kinetics of [35S]GTPγS and [3H]GDP to a mixture of G-proteins as well as individual classes of G-proteins upon binding of structurally different agonists to the M2 muscarinic acetylcholine receptor. KEY RESULTS Agonists displayed biphasic competition curves with the antagonist [3H]-N-methylscopolamine. GTPγS (1 µM) changed the competition curves to monophasic with low affinity and 50 µM GDP produced a similar effect. Depletion of membrane-bound GDP increased the proportion of agonist high-affinity sites. Carbachol accelerated the dissociation of [3H]GDP from membranes. The inverse agonist N-methylscopolamine slowed GDP dissociation and GTPγS binding without changing affinity for GDP. Carbachol affected both GDP association with and dissociation from Gi/o G-proteins but only its dissociation from Gs/olf G-proteins. CONCLUSIONS AND IMPLICATIONS These findings suggest the existence of a low-affinity agonist-receptor conformation complexed with GDP-liganded G-protein. Also the negative cooperativity between GDP and agonist binding at the receptor/G-protein complex determines agonist efficacy. GDP binding reveals differences in action of agonists versus inverse agonists as well as differences in activation of Gi/o versus Gs/olf G-proteins that are not identified by conventional GTPγS binding. PMID:20958290

  4. Negative cooperativity in binding of muscarinic receptor agonists and GDP as a measure of agonist efficacy.

    PubMed

    Jakubík, J; Janíčková, H; El-Fakahany, E E; Doležal, V

    2011-03-01

    Conventional determination of agonist efficacy at G-protein coupled receptors is measured by stimulation of guanosine-5'-γ-thiotriphosphate (GTPγS) binding. We analysed the role of guanosine diphosphate (GDP) in the process of activation of the M₂ muscarinic acetylcholine receptor and provide evidence that negative cooperativity between agonist and GDP binding is an alternative measure of agonist efficacy. Filtration and scintillation proximity assays measured equilibrium binding as well as binding kinetics of [³⁵S]GTPγS and [³H]GDP to a mixture of G-proteins as well as individual classes of G-proteins upon binding of structurally different agonists to the M₂ muscarinic acetylcholine receptor. Agonists displayed biphasic competition curves with the antagonist [³H]-N-methylscopolamine. GTPγS (1 µM) changed the competition curves to monophasic with low affinity and 50 µM GDP produced a similar effect. Depletion of membrane-bound GDP increased the proportion of agonist high-affinity sites. Carbachol accelerated the dissociation of [³H]GDP from membranes. The inverse agonist N-methylscopolamine slowed GDP dissociation and GTPγS binding without changing affinity for GDP. Carbachol affected both GDP association with and dissociation from G(i/o) G-proteins but only its dissociation from G(s/olf) G-proteins. These findings suggest the existence of a low-affinity agonist-receptor conformation complexed with GDP-liganded G-protein. Also the negative cooperativity between GDP and agonist binding at the receptor/G-protein complex determines agonist efficacy. GDP binding reveals differences in action of agonists versus inverse agonists as well as differences in activation of G(i/o) versus G(s/olf) G-proteins that are not identified by conventional GTPγS binding. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

  5. Cannabinoid receptor interacting protein suppresses agonist-driven CB1 receptor internalization and regulates receptor replenishment in an agonist-biased manner.

    PubMed

    Blume, Lawrence C; Leone-Kabler, Sandra; Luessen, Deborah J; Marrs, Glen S; Lyons, Erica; Bass, Caroline E; Chen, Rong; Selley, Dana E; Howlett, Allyn C

    2016-11-01

    Cannabinoid receptor interacting protein 1a (CRIP1a) is a CB1 receptor (CB1 R) distal C-terminus-associated protein that modulates CB1 R signaling via G proteins, and CB1 R down-regulation but not desensitization (Blume et al. [2015] Cell Signal., 27, 716-726; Smith et al. [2015] Mol. Pharmacol., 87, 747-765). In this study, we determined the involvement of CRIP1a in CB1 R plasma membrane trafficking. To follow the effects of agonists and antagonists on cell surface CB1 Rs, we utilized the genetically homogeneous cloned neuronal cell line N18TG2, which endogenously expresses both CB1 R and CRIP1a, and exhibits a well-characterized endocannabinoid signaling system. We developed stable CRIP1a-over-expressing and CRIP1a-siRNA-silenced knockdown clones to investigate gene dose effects of CRIP1a on CB1 R plasma membrane expression. Results indicate that CP55940 or WIN55212-2 (10 nM, 5 min) reduced cell surface CB1 R by a dynamin- and clathrin-dependent process, and this was attenuated by CRIP1a over-expression. CP55940-mediated cell surface CB1 R loss was followed by a cycloheximide-sensitive recovery of surface receptors (30-120 min), suggesting the requirement for new protein synthesis. In contrast, WIN55212-2-mediated cell surface CB1 Rs recovered only in CRIP1a knockdown cells. Changes in CRIP1a expression levels did not affect a transient rimonabant (10 nM)-mediated increase in cell surface CB1 Rs, which is postulated to be as a result of rimonabant effects on 'non-agonist-driven' internalization. These studies demonstrate a novel role for CRIP1a in agonist-driven CB1 R cell surface regulation postulated to occur by two mechanisms: 1) attenuating internalization that is agonist-mediated, but not that in the absence of exogenous agonists, and 2) biased agonist-dependent trafficking of de novo synthesized receptor to the cell surface.

  6. Attenuator And Conditioner

    SciTech Connect

    Anderson, Gene R.; Armendariz, Marcelino G.; Carson, Richard F.; Bryan, Robert P.; Duckett, III, Edwin B.; Kemme, Shanalyn Adair; McCormick, Frederick B.; Peterson, David W.

    2006-04-04

    An apparatus and method of attenuating and/or conditioning optical energy for an optical transmitter, receiver or transceiver module is disclosed. An apparatus for attenuating the optical output of an optoelectronic connector including: a mounting surface; an array of optoelectronic devices having at least a first end; an array of optical elements having at least a first end; the first end of the array of optical elements optically aligned with the first end of the array of optoelectronic devices; an optical path extending from the first end of the array of optoelectronic devices and ending at a second end of the array of optical elements; and an attenuator in the optical path for attenuating the optical energy emitted from the array of optoelectronic devices. Alternatively, a conditioner may be adapted in the optical path for conditioning the optical energy emitted from the array of optoelectronic devices.

  7. Protein intake and bone health.

    PubMed

    Bonjour, Jean-Philippe

    2011-03-01

    Adequate nutrition plays an important role in the development and maintenance of bone structures resistant to usual mechanical stresses. In addition to calcium in the presence of an adequate supply of vitamin D, dietary proteins represent key nutrients for bone health and thereby function in the prevention of osteoporosis. Several studies point to a positive effect of high protein intake on bone mineral density or content. This fact is associated with a significant reduction in hip fracture incidence, as recorded in a large prospective study carried out in a homogeneous cohort of postmenopausal women. Low protein intake (< 0.8 g/kg body weight/day) is often observed in patients with hip fractures and an intervention study indicates that following orthopedic management, protein supplementation attenuates post-fracture bone loss, tends to increase muscle strength, and reduces medical complications and rehabilitation hospital stay. There is no evidence that high protein intake per se would be detrimental for bone mass and strength. Nevertheless, it appears reasonable to avoid very high protein diets (i. e. more than 2.0 g/kg body weight/day) when associated with low calcium intake (i. e. less than 600 mg/day). In the elderly, taking into account the attenuated anabolic response to dietary protein with ageing, there is concern that the current dietary protein recommended allowance (RDA), as set at 0.8 g/kg body weight/day, might be too low for the primary and secondary prevention of fragility fractures.

  8. Fiber Optic Attenuators

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Mike Buzzetti designed a fiber optic attenuator while working at Jet Propulsion Laboratory, intended for use in NASA's Deep Space Network. Buzzetti subsequently patented and received an exclusive license to commercialize the device, and founded Nanometer Technologies to produce it. The attenuator functions without introducing measurable back-reflection or insertion loss, and is relatively insensitive to vibration and changes in temperature. Applications include cable television, telephone networks, other signal distribution networks, and laboratory instrumentation.

  9. Modification of kappa-opioid receptor agonist-induced antinociception by diabetes in the mouse brain and spinal cord.

    PubMed

    Ohsawa, Masahiro; Kamei, Junzo

    2005-05-01

    The supraspinal and spinal antinociceptive effects of several kappa-opioid receptor agonists were examined in diabetic and non-diabetic mice using the tail-flick assay. The antinociception induced by intrathecal (i.t.), but not intracerebroventricular (i.c.v.), CI-977, a highly selective kappa(1)-opioid receptor agonist, in diabetic mice was less than that in non-diabetic mice. The antinociceptive effects of ICI-199,441 and R-84760, high potency kappa(1)-opioid receptor agonists, given i.c.v., but not i.t., were attenuated in diabetic mice compared to those in non-diabetic mice. On the other hand, the antinociceptive effects of the new kappa-opioid receptor agonist TRK-820, which has high affinity for kappa(2)- and/or kappa(3)-opioid receptors, injected both i.c.v. and i.t. in diabetic mice were markedly less than those in non-diabetic mice. These results indicate that the antinociceptive effects of those kappa-opioid receptor agonists in diabetic mice are altered in a region-specific manner in the central nervous system (CNS). The dysfunction of kappa-opioid receptor subtypes in diabetic mice may underlie this CNS region-specific variation in the effects of these kappa-opioid receptor agonists.

  10. Dopaminergic agonists in Parkinson's disease.

    PubMed

    Alonso Cánovas, A; Luquin Piudo, R; García Ruiz-Espiga, P; Burguera, J A; Campos Arillo, V; Castro, A; Linazasoro, G; López Del Val, J; Vela, L; Martínez Castrillo, J C

    2014-05-01

    Non-ergoline dopamine agonists (DA) are effective treatments for Parkinson's disease (PD). This review presents the pharmacology, evidence of efficacy and safety profile of pramipexole, ropinirole, and rotigotine, and practical recommendations are given regarding their use in clinical practice. Extended-release formulations of pramipexole and ropinirole and transdermal continuous delivery rotigotine patches are currently available; these may contribute to stabilising of plasma levels. In early PD, the three drugs significantly improve disability scales, delay time to dyskinesia and allow a later introduction of levodopa. In late PD they reduced total 'off'-time, improved Unified Parkinson's Disease Rating Scale (UPDRS) in both 'on' and 'off' state and allowed a reduction in total levodopa dosage. A significant improvement in quality of life scales has also been demonstrated. Extended-release formulations have proved to be non-inferior to the immediate release formulations and are better tolerated (ropinirole). Despite a generally good safety profile, serious adverse events, such as impulse control disorder and sleep attacks, need to be routinely monitored. Although combination therapy has not been addressed in scientific literature, certain combinations, such as apomorphine and another DA, may be helpful. Switching from one DA to another is feasible and safe, although in the first days an overlap of dopaminergic side effects may occur. When treatment with DA is stopped abruptly, dopamine withdrawal syndrome may present. Suspending any DA, especially pramipexole, has been linked to onset of apathy, which may be severe. New non-ergotine DAs are a valuable option for the treatment of both early and late PD. Despite their good safety profile, serious adverse effects may appear; these effects may have a pathoplastic effect on the course of PD and need to be monitored. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  11. PPAR Agonists and Cardiovascular Disease in Diabetes

    PubMed Central

    Calkin, Anna C.; Thomas, Merlin C.

    2008-01-01

    Peroxisome proliferators activated receptors (PPARs) are ligand-activated nuclear transcription factors that play important roles in lipid and glucose homeostasis. To the extent that PPAR agonists improve diabetic dyslipidaemia and insulin resistance, these agents have been considered to reduce cardiovascular risk. However, data from murine models suggests that PPAR agonists also have independent anti-atherosclerotic actions, including the suppression of vascular inflammation, oxidative stress, and activation of the renin angiotensin system. Many of these potentially anti-atherosclerotic effects are thought to be mediated by transrepression of nuclear factor-kB, STAT, and activator protein-1 dependent pathways. In recent clinical trials, PPARα agonists have been shown to be effective in the primary prevention of cardiovascular events, while their cardiovascular benefit in patients with established cardiovascular disease remains equivocal. However, the use of PPARγ agonists, and more recently dual PPARα/γ coagonists, has been associated with an excess in cardiovascular events, possibly reflecting unrecognised fluid retention with potent agonists of the PPARγ receptor. Newer pan agonists, which retain their anti-atherosclerotic activity without weight gain, may provide one solution to this problem. However, the complex biologic effects of the PPARs may mean that only vascular targeted agents or pure transrepressors will realise the goal of preventing atherosclerotic vascular disease. PMID:18288280

  12. Long-term studies of dopamine agonists.

    PubMed

    Hubble, Jean P

    2002-02-26

    Dopamine agonists have long been used as adjunctive therapy for the treatment of Parkinson's disease (PD). In more recent years these drugs have also been proved safe and effective as initial therapy in lieu of levodopa in the treatment of PD. Long-term levodopa therapy is associated with motor complications, including fluctuating response patterns and dyskinesia. By initially introducing a dopamine agonist as symptomatic drug therapy, it may be possible to postpone the use of levodopa and delay or prevent the development of motor complications. Recently, four clinical trials have explored this hypothesis by comparing the long-term response and side effects of levodopa with dopamine agonist therapy. The drugs studied have included ropinirole, pramipexole, cabergoline, and pergolide. In each of these projects, the occurrence of motor complications, such as wearing off and dyskinesia, was significantly less in the subjects assigned to initiation of therapy with a dopamine agonist. The addition of levodopa could be postponed by many months or even several years. Therefore, these long-term studies of dopamine agonists support the initiation of a dopamine agonist instead of levodopa in an effort to postpone levodopa-related motor complications. This therapeutic approach may be particularly appropriate in PD patients with a long treatment horizon on the basis of age and general good health. The extension phase of the long-term study comparing pramipexole with levodopa is ongoing, and follow-up information may help to establish the value of this treatment strategy.

  13. Design and Synthesis of Dopaminergic Agonists.

    PubMed

    Matute, Maria Soledad; Matute, Rosa; Merino, Pedro

    2016-01-01

    The use of dopaminergic agonists is key in the treatment of Parkinson's disease and related central nervous system (CNS) neurodegenerative disorders. Despite there are a number of commercialized dopaminergic agonists that are currently being used successfully in the first stages of the disease, they often fail to provide sustained clinical benefit for a long period due to the appearance of side-effects such as augmentation, sleepiness, nausea, hypothension, and compulsive behaviors among others. New dopaminergic agonists with less side effects are being developed. These novel compounds offer an alternative when the disease progresses and patients fail to respond to standard dopaminergic treatments or side-effects increased. Chemistry, and in particular chemical synthesis, has played a major role in bringing synthetic dopaminergic agonists to the clinic and continues to be crucial for the development of new and necessary drugs for long-term treatments with less undesired side effects. A number of structural modifications of parent compounds have led to enhanced agonism but also partial agonism or even antagonism of one or more dopamine receptors. In some cases, these activities are accompanied by agonist effect at serotonin receptors which suggests a potential clinical application in the treatment of schizophrenia In this review, chemical synthesis of dopaminergic agents, their affinity, and the corresponding agonist/antagonist effects will be highlighted.

  14. Inhibitory effects of peroxisome proliferator-activated receptor γ agonists on collagen IV production in podocytes.

    PubMed

    Li, Yanjiao; Shen, Yachen; Li, Min; Su, Dongming; Xu, Weifeng; Liang, Xiubin; Li, Rongshan

    2015-07-01

    Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists have beneficial effects on the kidney diseases through preventing microalbuminuria and glomerulosclerosis. However, the mechanisms underlying these effects remain to be fully understood. In this study, we investigate the effects of PPAR-γ agonist, rosiglitazone (Rosi) and pioglitazone (Pio), on collagen IV production in mouse podocytes. The endogenous expression of PPAR-γ was found in the primary podocytes and can be upregulated by Rosi and Pio, respectively, detected by RT-PCR and Western blot. PPAR-γ agonist markedly blunted the increasing of collagen IV expression and extraction in podocytes induced by TGF-β. In contrast, adding PPAR-γ antagonist, GW9662, to podocytes largely prevented the inhibition of collagen IV expression from Pio treatment. Our data also showed that phosphorylation of Smad2/3 enhanced by TGF-β in a time-dependent manner was significantly attenuated by adding Pio. The promoter region of collagen IV gene contains one putative consensus sequence of Smad-binding element (SBE) by promoter analysis, Rosi and Pio significantly ameliorated TGF-β-induced SBE4-luciferase activity. In conclusion, PPAR-γ activation by its agonist, Rosi or Pio, in vitro directly inhibits collagen IV expression and synthesis in primary mouse podocytes. The suppression of collagen IV production was related to the inhibition of TGF-β-driven phosphorylation of Smad2/3 and decreased response activity of SBEs of collagen IV in PPAR-γ agonist-treated mouse podocytes. This represents a novel mechanistic support regarding PPAR-γ agonists as podocyte protective agents.

  15. The dopamine D(1) receptor agonist SKF-82958 serves as a discriminative stimulus in the rat.

    PubMed

    Haile, C N; Carey, G; Varty, G B; Coffin, V L

    2000-01-28

    We examined the discriminative stimulus effects of the high-efficacy dopamine D(1) receptor agonist (+/-)6-chloro-7, 8-dihydroxy-3-ally1-phenyl-2,3,4,5-tetrahydro-1H-3benzazepine++ + hydrobromide (SKF-82958) in rats trained to discriminate SKF-82958 (0.03 mg/kg) from vehicle in a two-lever food-reinforced drug discrimination task. SKF-82958 produced dose-related increases in responding to the SKF-82958 appropriate lever with full substitution occurring at the training dose. Pretreatment with the dopamine D(1)/D(5) receptor antagonist (-)-trans-6,7,7a,8,9, 13b-hexahydro-3-chloro-2hydroxy-N-methyl-5H-benzo-[d]naphtho -¿2, 1-b¿azepine (SCH-39166) (0.01 mg/kg) attenuated the discriminative stimulus effects of SKF-82958. Pretreatment with the dopamine D(2) receptor antagonist raclopride (0.03 mg/kg) had no effect. The high-efficacy dopamine D(1) receptor agonist R(+)6chloro-7, 8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide (SKF-81297) fully substituted for SKF-82958, whereas the low-efficacy dopamine D(1) receptor agonist (+/-)1-phenyl-2,3,4, 5-tetrahydro-(1H)-3-benzazepine-7,8-diol hydrochloride (SKF-38393) produced only partial substitution. The dopamine D(2) receptor agonist trans-(+/-)-4,4a,5,6,7,8,8a, 9-octahydro-5-propyl-1H-propyl-1H-pyrazolo[3,4-g]quinoline dihydrochloride (quinpirole) and the indirect dopamine agonist cocaine did not substitute fully for the SKF-82958 discriminative stimulus cue. These results demonstrate that the high-efficacy dopamine D(1) receptor agonist SKF-82958 can serve as an effective discriminative stimulus in the rat, and that these effects are mediated by a dopamine D(1)-like receptor mechanism.

  16. Menthol attenuates respiratory irritation responses to multiple cigarette smoke irritants

    PubMed Central

    Willis, Daniel N.; Liu, Boyi; Ha, Michael A.; Jordt, Sven-Eric; Morris, John B.

    2011-01-01

    Menthol, the cooling agent in peppermint, is added to almost all commercially available cigarettes. Menthol stimulates olfactory sensations, and interacts with transient receptor potential melastatin 8 (TRPM8) ion channels in cold-sensitive sensory neurons, and transient receptor potential ankyrin 1 (TRPA1), an irritant-sensing channel. It is highly controversial whether menthol in cigarette smoke exerts pharmacological actions affecting smoking behavior. Using plethysmography, we investigated the effects of menthol on the respiratory sensory irritation response in mice elicited by smoke irritants (acrolein, acetic acid, and cyclohexanone). Menthol, at a concentration (16 ppm) lower than in smoke of mentholated cigarettes, immediately abolished the irritation response to acrolein, an agonist of TRPA1, as did eucalyptol (460 ppm), another TRPM8 agonist. Menthol's effects were reversed by a TRPM8 antagonist, AMTB. Menthol's effects were not specific to acrolein, as menthol also attenuated irritation responses to acetic acid, and cyclohexanone, an agonist of the capsaicin receptor, TRPV1. Menthol was efficiently absorbed in the respiratory tract, reaching local concentrations sufficient for activation of sensory TRP channels. These experiments demonstrate that menthol and eucalyptol, through activation of TRPM8, act as potent counterirritants against a broad spectrum of smoke constituents. Through suppression of respiratory irritation, menthol may facilitate smoke inhalation and promote nicotine addiction and smoking-related morbidities.— Willis, D. N., Liu, B., Ha, M. A., Jordt, S.-E., Morris, J. B. Menthol attenuates respiratory irritation responses to multiple cigarette smoke irritants. PMID:21903934

  17. Numerical simulation of wave propagation in cancellous bone.

    PubMed

    Padilla, F; Bossy, E; Haiat, G; Jenson, F; Laugier, P

    2006-12-22

    Numerical simulation of wave propagation is performed through 31 3D volumes of trabecular bone. These volumes were reconstructed from high synchrotron microtomography experiments and are used as the input geometry in a simulation software developed in our laboratory. The simulation algorithm accounts for propagation into both the saturating fluid and bone but absorption is not taken into account. We show that 3D simulation predicts phenomena observed experimentally in trabecular bones : linear frequency dependence of attenuation, increase of attenuation and speed of sound with the bone volume fraction, negative phase velocity dispersion in most of the specimens, propagation of fast and slow wave depending on the orientation of the trabecular network compared to the direction of propagation of the ultrasound. Moreover, the predicted attenuation is in very close agreement with the experimental one measured on the same specimens. Coupling numerical simulation with real bone architecture therefore provides a powerful tool to investigate the physics of ultrasound propagation in trabecular structures.

  18. Effect of inhaled glucocorticoids and beta(2) agonists on vertebral fracture risk in COPD patients: the EOLO study.

    PubMed

    Gonnelli, S; Caffarelli, C; Maggi, S; Guglielmi, G; Siviero, P; Rossi, S; Crepaldi, G; Nuti, R

    2010-08-01

    Although inhaled glucocorticoids (GCs) and beta(2) agonists are being more frequently prescribed in the management of chronic obstructive pulmonary disease (COPD), their role in the impairment of bone status and in fracture risk remains controversial. This study aimed to evaluate whether the dose of inhaled GCs and beta(2) agonists may independently influence bone status and vertebral fracture risk in COPD patients aged 50 years or over. COPD severity, presence of vertebral fractures on lateral chest X-ray, and bone status by quantitative ultrasound (QUS) at the calcaneus were evaluated. The risk of vertebral fractures was significantly increased in patients taking the highest daily dose (>1,500 microg) of inhaled GCs (OR = 1.4, CI 1.04-1.89). The highest dose of inhaled GCs was significantly associated with low values of stiffness index (OR = 1.74, CI 1.03-2.94). Inhaled beta(2) agonists were not associated either with increased risk of vertebral fracture or with reduced values of stiffness. Moreover, the risk of fractures was markedly increased in patients with very severe or severe COPD (OR = 2.05, CI 1.28-3.28, and OR = 1.40, CI 1.06-1.82, respectively). In conclusion, in COPD patients high doses of inhaled GCs, but not beta(2) agonists, are associated with an increased risk of vertebral fractures and a reduction of QUS at the calcaneus.

  19. Effects of direct- and indirect-acting serotonin receptor agonists on the antinociceptive and discriminative stimulus effects of morphine in rhesus monkeys.

    PubMed

    Li, Jun-Xu; Koek, Wouter; Rice, Kenner C; France, Charles P

    2011-04-01

    Serotonergic (5-HT) systems modulate pain, and drugs acting on 5-HT systems are used with opioids to treat pain. This study examined the effects of 5-HT receptor agonists on the antinociceptive and discriminative stimulus effects of morphine in monkeys. Morphine increased tail-withdrawal latency in a dose-related manner; 5-HT receptor agonists alone increased tail-withdrawal latency at 50 °C but not 55 °C water. The antinociceptive effects of morphine occurred with smaller doses when monkeys received an indirect-acting (fenfluramine) or direct acting (8-OH-DPAT, F13714, buspirone, quipazine, DOM, and 2C-T-7) agonist. The role of 5-HT receptor subtypes in these interactions was confirmed with selective 5-HT(1A) (WAY100635) and 5-HT(2A) (MDL100907) receptor antagonists. None of the 5-HT drugs had morphine-like discriminative stimulus effects; however, fenfluramine and 5-HT(2A) receptor agonists attenuated the discriminative stimulus effects of morphine and this attenuation was prevented by MDL100907. The 5-HT(1A) receptor agonists did not alter the discriminative stimulus effects of morphine. Thus, 5-HT receptor agonists increase the potency of morphine in an assay of antinociception, even under conditions where 5-HT agonists are themselves without effect (ie, 55 °C water), without increasing (and in some cases decreasing) the potency of morphine in a drug discrimination assay. Whereas 5-HT(2A) receptor agonists increase the potency of morphine for antinociception at doses that have no effect on the rate of operant responding, 5-HT(1A) receptor agonists increase the potency of morphine only at doses that eliminate operant responding. These data suggest that drugs acting selectively on 5-HT receptor subtypes could help to improve the use of opioids for treating pain.

  20. Adverse Effects of GLP-1 Receptor Agonists

    PubMed Central

    Filippatos, Theodosios D.; Panagiotopoulou, Thalia V.; Elisaf, Moses S.

    2014-01-01

    Glucagon-like peptide-1 (GLP-1) receptor agonists are a class of injective anti-diabetic drugs that improve glycemic control and many other atherosclerosis-related parameters in patients with type 2 diabetes (T2D). However, the use of this relatively new class of drugs may be associated with certain adverse effects. Concerns have been expressed regarding the effects of these drugs on pancreatic and thyroid tissue, since animal studies and analyses of drug databases indicate an association of GLP-1 receptor agonists with pancreatitis, pancreatic cancer, and thyroid cancer. However, several meta-analyses failed to confirm a cause-effect relation between GLP-1 receptor agonists and the development of these adverse effects. One benefit of GLP-1 receptor agonists is that they do not cause hypoglycemia when combined with metformin or thiazolidinediones, but the dose of concomitant sulphonylurea or insulin may have to be decreased to reduce the risk of hypoglycemic episodes. On the other hand, several case reports have linked the use of these drugs, mainly exenatide, with the occurrence of acute kidney injury, primarily through hemodynamic derangement due to nausea, vomiting, and diarrhea. The most common symptoms associated with the use of GLP-1 receptor agonists are gastrointestinal symptoms, mainly nausea. Other common adverse effects include injection site reactions, headache, and nasopharyngitis, but these effects do not usually result in discontinuation of the drug. Current evidence shows that GLP-1 receptor agonists have no negative effects on the cardiovascular risk of patients with T2D. Thus, GLP-1 receptor agonists appear to have a favorable safety profile, but ongoing trials will further assess their cardiovascular effects. The aim of this review is to analyze critically the available data regarding adverse events of GLP-1 receptor agonists in different anatomic systems published in Pubmed and Scopus. Whenever possible, certain differences between GLP-1

  1. dAcsl, the Drosophila ortholog of acyl-CoA synthetase long-chain family member 3 and 4, inhibits synapse growth by attenuating bone morphogenetic protein signaling via endocytic recycling.

    PubMed

    Liu, Zhihua; Huang, Yan; Hu, Wen; Huang, Sheng; Wang, Qifu; Han, Junhai; Zhang, Yong Q

    2014-02-19

    Fatty acid metabolism plays an important role in brain development and function. Mutations in acyl-CoA synthetase long-chain family member 4 (ACSL4), which converts long-chain fatty acids to acyl-CoAs, result in nonsyndromic X-linked mental retardation. ACSL4 is highly expressed in the hippocampus, a structure critical for learning and memory. However, the underlying mechanism by which mutations of ACSL4 lead to mental retardation remains poorly understood. We report here that dAcsl, the Drosophila ortholog of ACSL4 and ACSL3, inhibits synaptic growth by attenuating BMP signaling, a major growth-promoting pathway at neuromuscular junction (NMJ) synapses. Specifically, dAcsl mutants exhibited NMJ overgrowth that was suppressed by reducing the doses of the BMP pathway components, accompanied by increased levels of activated BMP receptor Thickveins (Tkv) and phosphorylated mothers against decapentaplegic (Mad), the effector of the BMP signaling at NMJ terminals. In addition, Rab11, a small GTPase involved in endosomal recycling, was mislocalized in dAcsl mutant NMJs, and the membrane association of Rab11 was reduced in dAcsl mutant brains. Consistently, the BMP receptor Tkv accumulated in early endosomes but reduced in recycling endosomes in dAcsl mutant NMJs. dAcsl was also required for the recycling of photoreceptor rhodopsin in the eyes, implying a general role for dAcsl in regulating endocytic recycling of membrane receptors. Importantly, expression of human ACSL4 rescued the endocytic trafficking and NMJ phenotypes of dAcsl mutants. Together, our results reveal a novel mechanism whereby dAcsl facilitates Rab11-dependent receptor recycling and provide insights into the pathogenesis of ACSL4-related mental retardation.

  2. Bone Metabolism in Obesity and Weight Loss

    PubMed Central

    Shapses, Sue A.; Sukumar, Deeptha

    2014-01-01

    Excess body weight due to obesity has traditionally been considered to have a positive effect on bone; however, more recent findings suggest that bone quality is compromised. Both obesity and caloric restriction increase fracture risk and are regulated by endocrine factors and cytokines that have direct and indirect effects on bone and calcium absorption. Weight reduction will decrease bone mass and mineral density, but this varies by the individual’s age, gender, and adiposity. Dietary modifications, exercise, and medications have been shown to attenuate the bone loss associated with weight reduction. Future obesity and weight loss trials would benefit from assessment of key hormones, adipokine and gut peptides that regulate calcium absorption, and bone mineral density and quality by using sensitive techniques in high-risk populations. PMID:22809104

  3. Effects of salvinorin A on locomotor sensitization to D2/D3 dopamine agonist quinpirole.

    PubMed

    Beerepoot, Pieter; Lam, Vincent; Luu, Alice; Tsoi, Bernice; Siebert, Daniel; Szechtman, Henry

    2008-12-03

    Locomotor sensitization induced by the dopamine agonist quinpirole can be potentiated by co-treatment with the synthetic kappa opioid agonist U69593. The identification of salvinorin A, an active component of