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Sample records for protein pthrp lactation

  1. Parathyroid hormone-related protein (pthrp) is a gravisensor for lung and bone.

    NASA Astrophysics Data System (ADS)

    Torday, J.

    Parathyroid Hormone-related Protein (PTHrP) and its receptor represent a stretch- sensitive paracrine signaling mechanism (Torday, 1999) that may sense gravity. PTHrP has been shown to be essential for the development and homeostatic regulation of lung (Rubin et al, 2000) and bone (Kronenberg et al, 1994). Since both lung and bone structure and function are affected by microgravity, we hypothesized that microgravity down-regulates PTHrP signaling. To test this hypothesis, we suspended lung and bone cells in the microgravity environment of a rotating wall vessel apparatus, which simulates microgravity, for up to 72 hours. During the first 6-8 hours, PTHrP expression fell precipitously, decreasing by 80-90%; during the subsequent 64-66 hours, PTHrP expression remained at this newly established level. PTHrP production decreased from 5 pmol/ml/3hours to undetectable levels in culture medium from microgravity-exposed cells. The cells were then put back in culture at unit gravity for 24hours, and PTHrP expression and production returned to normal levels. Based on these findings, we have obtained bones from rats flown in space for 2 weeks (mission SLS-2, provided courtesy of the Biospecimen Facility, Ames Research Center, NASA, as a result of a peer-reviewed proposal). Analysis of PTHrP expression by femurs and tibias from these animals (n=5) revealed that PTHrP expression was 60% lower than in bones from ground-based rats. Interestingly, there were no differences in PTHrP exp ression by parietal bones, indicating that the effect of weightlessness on PTHrP expression is due to the unweighting of weight-bearing bones. This finding is consistent with other studies of microgravity-induced osteoporosis. The loss of the PTHrP signaling mechanism may be corrected using chemical agents that up-regulate this pathway.

  2. The Role of Parathyroid Hormone-Related Protein (PTHrP) in Osteoblast Response to Microgravity: Mechanistic Implications for Osteoporosis Development.

    PubMed

    Camirand, Anne; Goltzman, David; Gupta, Ajay; Kaouass, Mohammadi; Panda, Dibyendu; Karaplis, Andrew

    2016-01-01

    Prolonged skeletal unloading through bedrest results in bone loss similar to that observed in elderly osteoporotic patients, but with an accelerated timeframe. This rapid effect on weight-bearing bones is also observed in astronauts who can lose up to 2% of their bone mass per month spent in Space. Despite the important implications for Spaceflight travelers and bedridden patients, the exact mechanisms involved in disuse osteoporosis have not been elucidated. Parathyroid hormone-related protein (PTHrP) regulates many physiological processes including skeletal development, and has been proposed as a mechanosensor. To investigate the role of PTHrP in microgravity-induced bone loss, trabecular and calvarial osteoblasts (TOs and COs) from Pthrp +/+ and -/- mice were subjected to actual Spaceflight for 6 days (Foton M3 satellite). Pthrp +/+, +/- and -/- osteoblasts were also exposed to simulated microgravity for periods varying from 6 days to 6 weeks. While COs displayed little change in viability in 0g, viability of all TOs rapidly decreased in inverse proportion to PTHrP expression levels. Furthermore, Pthrp+/+ TOs displayed a sharp viability decline after 2 weeks at 0g. Microarray analysis of Pthrp+/+ TOs after 6 days in simulated 0g revealed expression changes in genes encoding prolactins, apoptosis/survival molecules, bone metabolism and extra-cellular matrix composition proteins, chemokines, insulin-like growth factor family members and Wnt-related signalling molecules. 88% of 0g-induced expression changes in Pthrp+/+ cells overlapped those caused by Pthrp ablation in normal gravity, and pulsatile treatment with PTHrP1-36 not only reversed a large proportion of 0g-induced effects in Pthrp+/+ TOs but maintained viability over 6-week exposure to microgravity. Our results confirm PTHrP efficacy as an anabolic agent to prevent microgravity-induced cell death in TOs. PMID:27463808

  3. The Role of Parathyroid Hormone-Related Protein (PTHrP) in Osteoblast Response to Microgravity: Mechanistic Implications for Osteoporosis Development

    PubMed Central

    Camirand, Anne; Goltzman, David; Gupta, Ajay; Kaouass, Mohammadi; Panda, Dibyendu; Karaplis, Andrew

    2016-01-01

    Prolonged skeletal unloading through bedrest results in bone loss similar to that observed in elderly osteoporotic patients, but with an accelerated timeframe. This rapid effect on weight-bearing bones is also observed in astronauts who can lose up to 2% of their bone mass per month spent in Space. Despite the important implications for Spaceflight travelers and bedridden patients, the exact mechanisms involved in disuse osteoporosis have not been elucidated. Parathyroid hormone-related protein (PTHrP) regulates many physiological processes including skeletal development, and has been proposed as a mechanosensor. To investigate the role of PTHrP in microgravity-induced bone loss, trabecular and calvarial osteoblasts (TOs and COs) from Pthrp +/+ and -/- mice were subjected to actual Spaceflight for 6 days (Foton M3 satellite). Pthrp +/+, +/- and -/- osteoblasts were also exposed to simulated microgravity for periods varying from 6 days to 6 weeks. While COs displayed little change in viability in 0g, viability of all TOs rapidly decreased in inverse proportion to PTHrP expression levels. Furthermore, Pthrp+/+ TOs displayed a sharp viability decline after 2 weeks at 0g. Microarray analysis of Pthrp+/+ TOs after 6 days in simulated 0g revealed expression changes in genes encoding prolactins, apoptosis/survival molecules, bone metabolism and extra-cellular matrix composition proteins, chemokines, insulin-like growth factor family members and Wnt-related signalling molecules. 88% of 0g-induced expression changes in Pthrp+/+ cells overlapped those caused by Pthrp ablation in normal gravity, and pulsatile treatment with PTHrP1-36 not only reversed a large proportion of 0g-induced effects in Pthrp+/+ TOs but maintained viability over 6-week exposure to microgravity. Our results confirm PTHrP efficacy as an anabolic agent to prevent microgravity-induced cell death in TOs. PMID:27463808

  4. PTHrP in differentiating human mesenchymal stem cells: transcript isoform expression, promoter methylation, and protein accumulation.

    PubMed

    Longo, Alessandra; Librizzi, Mariangela; Naselli, Flores; Caradonna, Fabio; Tobiasch, Edda; Luparello, Claudio

    2013-10-01

    Human PTHrP gene displays a complex organization with nine exons producing diverse mRNA variants due to alternative splicing at 5' and 3' ends and the existence of three different transcriptional promoters (P1, P2 and P3), two of which (P2 and P3) contain CpG islands. It is known that the expression of PTHrP isoforms may be differentially regulated in a developmental stage- and tissue-specific manner. To search for novel molecular markers of stemness/differentiation, here we have examined isoform expression in fat-derived mesenchymal stem cells both maintained in stem conditions and induced toward adipo- and osteogenesis. In addition, the expression of the splicing isoforms derived from P2 and P3 promoters was correlated to the state of methylation of the latter. Moreover, we also performed a quantitative evaluation of intracellular and secreted PTHrP protein product in undifferentiated stem cells and in parallel cultures at various differentiation stages. The data obtained indicate that from the stemness condition to that of osteo- and adipo-genic differentiated cells, the expression of isoforms becomes increasingly selective, thereby being a potential gene signature for the monitoring of cell stem or committed/differentiating state and that the switching-off of PTHrP isoform expression is mostly promoter methylation-dependent. Moreover, PTHrP intracellular retention is down-regulated in osteo-differentiating cells whereas the secretion of the protein in the extracellular medium is up-regulated with respect to stem cells, thereby suggesting that these variations of the intracellular and extracellular levels of PTHrP could potentially be enclosed in the list of the available protein signature of osteogenic differentiation. PMID:23810909

  5. Acoustic wave biosensor for the detection of the breast and prostate cancer metastasis biomarker protein PTHrP.

    PubMed

    Crivianu-Gaita, Victor; Aamer, Mohamed; Posaratnanathan, Roy T; Romaschin, Alexander; Thompson, Michael

    2016-04-15

    There are currently no biosensors that are able to reliably detect the process of cancer metastasis. We describe the first label-free real-time ultra-high frequency acoustic wave biosensor prototype capable of detecting the breast and prostate cancer metastasis biomarker, parathyroid hormone-related peptide (PTHrP). Two different linkers - 11-trichlorosilyl-undecanoic acid pentafluorophenyl ester (PFP) and S-(11-trichlorosilyl-undecanyl)-benzothiosulfonate (TUBTS) - were used to immobilize whole anti-PTHrP antibodies and Fab' fragments to surfaces as biorecognition elements. The biosensor surfaces were optimized using X-ray photoelectron spectroscopy (XPS) and the ultra-high frequency electromagnetic piezoelectric acoustic sensor (EMPAS). One optimized whole antibody-based surface (PFP/protein G'/whole antibodies/ethanolamine) and one optimized Fab' fragment-based surface (TUBTS/Fab' fragments) were tested as biosensors. It was determined that an in-line injection of bovine serum albumin prior to analyte injection yielded the most minimally fouling surfaces. Each surface was tested with no mass amplification and with sandwich-type secondary antibody mass amplification. The whole antibody-based mass-amplified biosensor yielded the lowest limit of detection (61 ng/mL), highest sensitivity, and a linear range from 61 ng/mL to 100 μg/mL. However, the Fab' fragment-based biosensor displayed better regenerability as a loss of ~20% of the initial analyte signal intensity was observed with each subsequent injection. The whole antibody-based biosensor was only capable of producing an analyte signal in the first injection. PMID:26594891

  6. Mid-region parathyroid hormone-related protein (PTHrP) binds chromatin of MDA-MB231 breast cancer cells and isolated oligonucleotides "in vitro".

    PubMed

    Sirchia, Rosalia; Priulla, Marcella; Sciandrello, Giulia; Caradonna, Fabio; Barbata, Giuseppa; Luparello, Claudio

    2007-09-01

    We have previously shown that PTHrP(38-94)-amide restrains growth and invasion "in vitro", causes striking toxicity and accelerates death of some breast cancer cell lines, the most responsive being MDA-MB231 whose tumorigenesis was also attenuated "in vivo". PTHrP(38-94)-amide contains the domain implicated in the nuclear import of PTHrP. Although the nucleus was identified as a destination for mid-region PTHrP, evidence for direct DNA-binding capability is lacking to date. Here, we examined the localization of PTHrP(38-94)-amide within MDA-MB231 cells and within metaphase spread preparations and characterized its DNA-binding properties, employing a combination of immunocytochemical, cytogenetic, "whole genome"/conventional PCR, EMSA and DNase footprinting techniques. The results obtained: (i) show that PTHrP(38-94)-amide gains access to the nuclear compartment of MDA-MB231 cell; (ii) demonstrate that PTHrP(38-94)-amide is a DNA-binding peptide; and, (iii) represent the first data to date on the potential molecular targets in both cellular chromatin and isolated oligonucleotides "in vitro". PMID:17124555

  7. Periosteal PTHrP Regulates Cortical Bone Remodeling During Fracture Healing.

    PubMed

    Wang, Meina; Nasiri, Ali R; Broadus, Arthur E; Tommasini, Steven M

    2015-12-01

    Parathyroid hormone-related protein (PTHrP) is widely expressed in the fibrous outer layer of the periosteum (PO), and the PTH/PTHrP type I receptor (PTHR1) is expressed in the inner PO cambial layer. The cambial layer gives rise to the PO osteoblasts (OBs) and osteoclasts (OCs) that model/remodel the cortical bone surface during development as well as during fracture healing. PTHrP has been implicated in the regulation of PO modeling during development, but nothing is known as regards a role of PTHrP in this location during fracture healing. We propose that PTHrP in the fibrous layer of the PO may be a key regulatory factor in remodeling bone formation during fracture repair. We first assessed whether PTHrP expression in the fibrous PO is associated with PO osteoblast induction in the subjacent cambial PO using a tibial fracture model in PTHrP-lacZ mice. Our results revealed that both PTHrP expression and osteoblast induction in PO were induced 3 days post-fracture. We then investigated a potential functional role of PO PTHrP during fracture repair by performing tibial fracture surgery in 10-week-old CD1 control and PTHrP conditional knockout (PTHrP cKO) mice that lack PO PTHrP. We found that callus size and formation as well as woven bone mineralization in PTHrP cKO mice were impaired compared to that in CD1 mice. Concordant with these findings, functional enzyme staining revealed impaired OB formation and OC activity in the cKO mice. We conclude that deleting PO PTHrP impairs cartilaginous callus formation, maturation and ossification as well as remodeling during fracture healing. These data are the initial genetic evidence suggesting that PO PTHrP may induce osteoblastic activity and regulate fracture healing on the cortical bone surface. PMID:26164475

  8. PTHrP promotes malignancy of human oral cancer cell downstream of the EGFR signaling

    SciTech Connect

    Yamada, Tamaki; Tsuda, Masumi; Ohba, Yusuke Kawaguchi, Hideaki; Totsuka, Yasunori; Shindoh, Masanobu

    2008-04-11

    Parathyroid hormone-related protein (PTHrP) is detected in many aggressive tumors and involved in malignant conversion; however, the underlying mechanism remains obscure. Here, we identified PTHrP as a mediator of epidermal growth factor receptor (EGFR) signaling to promote the malignancies of oral cancers. PTHrP mRNA was abundantly expressed in most of the quiescent oral cancer cells, and was significantly upregulated by EGF stimulation via ERK and p38 MAPK. PTHrP silencing by RNA interference, as well as EGFR inhibitor AG1478 treatment, significantly suppressed cell proliferation, migration, and invasiveness. Furthermore, combined treatment of AG1478 and PTHrP knockdown achieved synergistic inhibition of malignant phenotypes. Recombinant PTHrP substantially promoted cell motility, and rescued the inhibition by PTHrP knockdown, suggesting the paracrine/autocrine function of PTHrP. These data indicate that PTHrP contributes to the malignancy of oral cancers downstream of EGFR signaling, and may thus provide a therapeutic target for oral cancer.

  9. Induction of chronic pancreatitis by pancreatic duct ligation activates BMP2, apelin, and PTHrP expression in mice.

    PubMed

    Rastellini, Cristiana; Han, Song; Bhatia, Vandanajay; Cao, Yanna; Liu, Ka; Gao, Xuxia; Ko, Tien C; Greeley, George H; Falzon, Miriam

    2015-10-01

    Chronic pancreatitis (CP) is a devastating disease with no treatments. Experimental models have been developed to reproduce the parenchyma and inflammatory responses typical of human CP. For the present study, one objective was to assess and compare the effects of pancreatic duct ligation (PDL) to those of repetitive cerulein (Cer)-induced CP in mice on pancreatic production of bone morphogenetic protein-2 (BMP2), apelin, and parathyroid hormone-related protein (PTHrP). A second objective was to determine the extent of cross talk among pancreatic BMP2, apelin, and PTHrP signaling systems. We focused on BMP2, apelin, and PTHrP since these factors regulate the inflammation-fibrosis cascade during pancreatitis. Findings showed that PDL- and Cer-induced CP resulted in significant elevations in expression and peptide/protein levels of pancreatic BMP2, apelin, and PTHrP. In vivo mouse and in vitro pancreatic cell culture experiments demonstrated that BMP2 stimulated pancreatic apelin expression whereas apelin expression was inhibited by PTHrP exposure. Apelin or BMP2 exposure inhibited PTHrP expression, and PTHrP stimulated upregulation of gremlin, an endogenous inhibitor of BMP2 activity. Transforming growth factor-β (TGF-β) stimulated PTHrP expression. Together, findings demonstrated that PDL- and Cer-induced CP resulted in increased production of the pancreatic BMP2, apelin, and PTHrP signaling systems and that significant cross talk occurred among pancreatic BMP2, apelin, and PTHrP. These results together with previous findings imply that these factors interact via a pancreatic network to regulate the inflammation-fibrosis cascade during CP. More importantly, this network communicated with TGF-β, a key effector of pancreatic pathophysiology. This novel network may be amenable to pharmacologic manipulations during CP in humans. PMID:26229008

  10. Lactation

    PubMed Central

    1989-01-01

    period when the use of artificial teats and dummies (pacifiers) may condition the infant to different oral actions that are inappropriate for breast-feeding. Comparisons of breast milk and cow's milk fail to describe the many important differences between them, e.g., the structural and qualitative differences in proteins and fats, and the bioavailability of minerals. The protection against infection and allergies conferred on the infant, which is impossible to attain through any other feeding regimen, is one of breast milk's most outstanding qualities. The maximum birth-spacing effect of lactation is achieved when an infant is fully, or nearly fully, breast-fed and the mother consequently remains amenorrhoeic. PMID:20604468

  11. Parathyroid hormone-related peptide (PTHrP): prokaryotic expression, purification, and preparation of a polyclonal antibody.

    PubMed

    Zheng, H L; Li, H; Sun, Y S; Yang, Z Y; Yu, Q

    2014-01-01

    Parathyroid hormone-related peptide (PTHrP) plays important roles in promoting cancer occurrence and in the development of bone metastases. To increase our knowledge of the biological functions of PTHrP, the prokaryotic expression vector pET-PTHrP was successfully constructed and the His-PTHrP fusion protein was expressed in Escherichia coli. Anti-PTHrP polyclonal antibody was then prepared from rabbits. Finally, the goat tissue expression profile of PTHrP was analyzed by Western blot with the anti-PTHrP polyclonal antibody. The results showed that the expression of PTHrP in goat mammary glands was significantly higher than that in other organs. This indicates that PTHrP may play important roles in the goat mammary gland. The antibody prepared will be a useful tool for detecting PTHrP and will be valuable in future studies investigating the role of PTHrP in calcium metabolism in the goat model. PMID:25158263

  12. PTHrP Gene Expression in Cancer: Do All Paths Lead to Ets?

    PubMed Central

    Richard, Virgile; Rosol, Thomas J.; Foley, John

    2010-01-01

    Parathyroid hormone-related protein (PTHrP) came to the attention of the scientific community in the mid-1980s because of its association with the paraneoplastic syndrome of humoral hypercalcemia of malignancy. Recently, a crucial role for the peptide has been identified in the metastatic growth of cancer cells in bone. Efforts to understand the peptide’s role in these pathological processes have evolved into the study of PTHrP gene expression. Currently, regulation of the third PTHrP promoter is beginning to be understood in the context of activation of certain signaling pathways involved in the growth and progression of specific neoplasms. In addition, factors that modulate the entire PTHrP-transcriptional unit, as well as the stability of the mRNA, are being elucidated at the level of cis-acting sequences. PMID:16022632

  13. Acinar cell-specific knockout of the PTHrP gene decreases the proinflammatory and profibrotic responses in pancreatitis

    PubMed Central

    Bhatia, Vandanajay; Rastellini, Cristiana; Han, Song; Aronson, Judith F.; Greeley, George H.

    2014-01-01

    Pancreatitis is a necroinflammatory disease with acute and chronic manifestations. Accumulated damage incurred during repeated bouts of acute pancreatitis (AP) can lead to chronic pancreatitis (CP). Pancreatic parathyroid hormone-related protein (PTHrP) levels are elevated in a mouse model of cerulein-induced AP. Here, we show elevated PTHrP levels in mouse models of pancreatitis induced by chronic cerulein administration and pancreatic duct ligation. Because acinar cells play a major role in the pathophysiology of pancreatitis, mice with acinar cell-specific targeted disruption of the Pthrp gene (PTHrPΔacinar) were generated to assess the role of acinar cell-secreted PTHrP in pancreatitis. These mice were generated using Cre-LoxP technology and the acinar cell-specific elastase promoter. PTHrPΔacinar exerted protective effects in cerulein and pancreatic duct ligation models, evident as decreased edema, histological damage, amylase secretion, pancreatic stellate cell (PSC) activation, and extracellular matrix deposition. Treating acinar cells in vitro with cerulein increased IL-6 expression and NF-κB activity; these effects were attenuated in PTHrPΔacinar cells, as were the cerulein- and carbachol-induced elevations in amylase secretion. The cerulein-induced upregulation of procollagen I expression was lost in PSCs from PTHrPΔacinar mice. PTHrP immunostaining was elevated in human CP sections. The cerulein-induced upregulation of IL-6 and ICAM-1 (human acinar cells) and procollagen I (human PSCs) was suppressed by pretreatment with the PTH1R antagonist, PTHrP (7–34). These findings establish PTHrP as a novel mediator of inflammation and fibrosis associated with CP. Acinar cell-secreted PTHrP modulates acinar cell function via its effects on proinflammatory cytokine release and functions via a paracrine pathway to activate PSCs. PMID:25035110

  14. Lactation-induced cadmium-binding proteins

    SciTech Connect

    Bhattacharyya, M.H.; Solaiman, D.; Garvey, J.S.; Miyazaki, W.Y.

    1987-01-01

    Previously we have demonstrated an increase during midlactation in /sup 109/Cd adsorption and increased retention by the duodenum, kidney, and mammary tissue of mouse dams receiving environmental levels of cadmium//sup 109/Cd via drinking water, with little change in /sup 109/Cd retention in liver and jejunum compared to nonpregnant controls. Results are reported here of a study of cadmium deposition during midlactation as associated with induction of metallothionein (MT). A cadmium/hemoglobin (Cd/Hb) assay and radioimmunoassay for MT which measures heat-stable cadmium binding capacity in tissues was used to determine MT concentrations in fractions of kidney, liver, duodenum, and jejunum from female mice. Both assays demonstrated clear lactation-induced increases in MT concentrations in liver, kidney, and duodenum, with MT concentrations falling rapidly to control levels after weaning. 4 refs., 1 tab.

  15. The paracrine feedback loop between vitamin D₃ (1,25(OH)₂D₃) and PTHrP in prehypertrophic chondrocytes.

    PubMed

    Bach, Frances C; Rutten, Kirsten; Hendriks, Kristyanne; Riemers, Frank M; Cornelissen, Peter; de Bruin, Alain; Arkesteijn, Ger J; Wubbolts, Richard; Horton, William A; Penning, Louis C; Tryfonidou, Marianna A

    2014-12-01

    The endocrine feedback loop between vitamin D3(1,25(OH)2D3) and parathyroid hormone (PTH) plays a central role in skeletal development. PTH-related protein (PTHrP) shares homology and its receptor (PTHR1) with PTH. The aim of this study was to investigate whether there is a functional paracrine feedback loop between 1,25(OH)2D3 and PTHrP in the growth plate, in parallel with the endocrine feedback loop between 1,25(OH)2D3 and PTH. This was investigated in ATDC5 cells treated with 10(-8) M 1,25(OH)2D3 or PTHrP, Col2-pd2EGFP transgenic mice, and primary Col2-pd2EGFP growth plate chondrocytes isolated by FACS, using RT-qPCR, Western blot, PTHrP ELISA, chromatin immunoprecipitation (ChIP) assay, silencing of the 1,25(OH)2D3 receptor (VDR), immunofluorescent staining, immunohistochemistry, and histomorphometric analysis of the growth plate. The ChIP assay confirmed functional binding of the VDR to the PTHrP promoter, but not to the PTHR1 promoter. Treatment with 1,25(OH)2D3 decreased PTHrP protein production, an effect which was prevented by silencing of the VDR. Treatment with PTHrP significantly induced VDR production, but did not affect 1α- and 24-hydroxylase expression. Hypertrophic differentiation was inhibited by PTHrP and 1,25(OH)2D3 treatment. Taken together, these findings indicate that there is a functional paracrine feedback loop between 1,25(OH)2D3 and PTHrP in the growth plate. 1,25(OH)2D3 decreases PTHrP production, while PTHrP increases chondrocyte sensitivity to 1,25(OH)2D3 by increasing VDR production. In light of the role of 1,25(OH)2D3 and PTHrP in modulating chondrocyte differentiation, 1,25(OH)2D3 in addition to PTHrP could potentially be used to prevent undesirable hypertrophic chondrocyte differentiation during cartilage repair or regeneration. PMID:24777663

  16. An unusual mediastinal parathyroid carcinoma coproducing PTH and PTHrP: A case report

    PubMed Central

    CAO, CHUANGJIE; DOU, CHENGYUN; CHEN, FUQIN; WANG, YAN; ZHANG, XIAOLI; LAI, HONG

    2016-01-01

    Parathyroid carcinoma (PTCA) is a rare disease, and ectopic PTCA is particularly rare. Parathyroid hormone-related protein (PTHrP) expression in PTCA has not been previously described in the relevant literature to the best of our knowledge. The present study reports a unique case with a mediastinal parathyroid carcinoma producing parathyroid hormone (PTH) and PTHrP. A 53-year-old man presented with hyperparathyroidism symptoms, including fatigue, chest pain, dizziness, muscular soreness, polyuria, night sweats and renal stones. However, neck ultrasound revealed no significantly abnormal thyroid or parathyroid nodules. Tc99m methoxyisobutylisonitrile (Tc99m-MIBI) scintigraphy scanning indicated an ectopic mediastinal parathyroid adenoma. Histopathological examination revealed PTCA, and the tumor tissue was coproducing PTH and PTHrP. The patient underwent successful surgical operation. Serum calcium and PTH levels remained within normal ranges, and there was no tumor recurrence observed at a 3-year follow-up appointment. Although rare, ectopic parathyroid glands may lead to malignant disease. Clinical symptoms, biochemical tests, ultrasound and Tc99m-MIBI scintigraphy scanning may assist with the diagnosis of this disease. Hypersecretion of PTHrP and PTH contributed collaboratively to the pathogenesis of hypercalcemia due to PTCA. Complete surgical resection with microscopically negative margins is the recommended treatment for PTCA and offers the best chance of a cure. PMID:27313750

  17. The multifaceted actions of PTHrP in skeletal metastasis

    PubMed Central

    Soki, Fabiana N; Park, Serk In; McCauley, Laurie K

    2012-01-01

    PTHrP, identified during the elucidation of mediators of malignancy-induced hypercalcemia, plays numerous roles in normal physiology as well as pathological conditions. Recent data support direct functions of PTHrP in metastasis, particularly from tumors with strong bone tropism. Bone provides a unique metastatic environment because of mineralization and the diverse cell populations in the bone marrow. PTHrP is a key regulator of tumor–bone interactions and regulates cells in the bone microenvironment through proliferative and prosurvival activities that prime the ‘seed’ and the ‘soil’ of the metastatic lesion. This review highlights recent findings regarding the role of PTHrP in skeletal metastasis, including direct actions in tumor cells, as well as alterations in the bone microenvironment and future perspectives involving the potential roles of PTHrP in the premetastatic niche, and tumor dormancy. PMID:22830401

  18. LUD, a new protein domain associated with lactate utilization

    PubMed Central

    2013-01-01

    Background A novel highly conserved protein domain, DUF162 [Pfam: PF02589], can be mapped to two proteins: LutB and LutC. Both proteins are encoded by a highly conserved LutABC operon, which has been implicated in lactate utilization in bacteria. Based on our analysis of its sequence, structure, and recent experimental evidence reported by other groups, we hereby redefine DUF162 as the LUD domain family. Results JCSG solved the first crystal structure [PDB:2G40] from the LUD domain family: LutC protein, encoded by ORF DR_1909, of Deinococcus radiodurans. LutC shares features with domains in the functionally diverse ISOCOT superfamily. We have observed that the LUD domain has an increased abundance in the human gut microbiome. Conclusions We propose a model for the substrate and cofactor binding and regulation in LUD domain. The significance of LUD-containing proteins in the human gut microbiome, and the implication of lactate metabolism in the radiation-resistance of Deinococcus radiodurans are discussed. PMID:24274019

  19. Role of PTHrP(1-34) Pulse Frequency Versus Pulse Duration to Enhance Mesenchymal Stromal Cell Chondrogenesis.

    PubMed

    Fischer, Jennifer; Ortel, Marlen; Hagmann, Sebastien; Hoeflich, Andreas; Richter, Wiltrud

    2016-12-01

    Generation of phenotypically stable, articular chondrocytes from mesenchymal stromal cells (MSCs) is still an unaccomplished task, with formation of abundant, hyaline extracellular matrix, and avoidance of hypertrophy being prime challenges. We recently demonstrated that parathyroid hormone-related protein (PTHrP) is a promising factor to direct chondrogenesis of MSCs towards an articular phenotype, since intermittent PTHrP application stimulated cartilage matrix production and reduced undesired hypertrophy. We here investigated the role of frequency, pulse duration, total exposure time, and underlying mechanisms in order to unlock the full potential of PTHrP actions. Human MSC subjected to in vitro chondrogenesis for six weeks were exposed to 2.5 nM PTHrP(1-34) pulses from days 7 to 42. Application frequency was increased from three times weekly (3 × 6 h/week) to daily maintaining either the duration of individual pulses (6 h/day) or total exposure time (18 h/week; 2.6 h/day). Daily PTHrP treatment significantly increased extracellular matrix deposition regardless of pulse duration and suppressed alkaline-phosphatase activity by 87%. High total exposure time significantly reduced cell proliferation at day 14. Pulse duration was critically important to significantly reduce IHH expression, but irrelevant for PTHrP-induced suppression of the hypertrophic markers MEF2C and IBSP. COL10A1, RUNX2, and MMP13 expression remained unaltered. Decreased IGFBP-2, -3, and -6 expression suggested modulated IGF-I availability in PTHrP groups, while drop of SOX9 protein levels during the PTHrP-pulse may delay chondroblast formation and hypertrophy. Overall, the significantly optimized timing of PTHrP-pulses demonstrated a vast potential to enhance chondrogenesis of MSC and suppress hypertrophy possibly via superior balancing of IGF- and SOX9-related mechanisms. J. Cell. Physiol. 231: 2673-2681, 2016. © 2016 Wiley Periodicals, Inc. PMID:27548511

  20. Maternal protein reserves and their influence on lactational performance in rats. 3. The effects of dietary protein restriction and stage of lactation on milk composition.

    PubMed

    Pine, A P; Jessop, N S; Oldham, J D

    1994-12-01

    The effects of severe protein restriction following parturition on the changes in rat milk composition during lactation were investigated using multiparous female Sprague-Dawley rats caged individually following mating and offered a high-protein diet (H; 215 g crude protein (N x 6.25; CP)/kg dry matter (DM)) ad lib. until parturition. Following parturition, half the females continued to receive diet H, whilst the remainder were offered a diet low in protein (L; 90 g CP/kg DM) ad lib. On days 2, 4, 8 and 12 of lactation groups of females from both dietary treatments were used to provide a milk sample. Milk samples were analysed for their lactose (enzymically), protein (binding to Coomassie blue), lipid (gravimetrically) and mineral (spectrophotometrically) contents. The milk lactose concentration of group H increased with stage of lactation (r2 0.85, P < 0.001). Such an increase was prevented by diet L, and from day 8 of lactation the milk lactose of group L was lower (P < 0.05) than in group H. Group H milk protein concentration did not change during lactation and averaged 90.7 mg/g. Dietary protein restriction reduced the milk protein concentration of group L so that on days 2, 4 and 12 of lactation it was lower (P < 0.05) than that of group H. On day 8 of lactation the milk protein concentration of group L had increased (P < 0.05) and was comparable with that of group H. For group H, milk lipid averaged 166.8 mg/g and was generally unchanged during lactation. Diet L increased (P < 0.01) the milk lipid concentration (205.5 mg/g) compared with diet H and this was also significant on days 4 and 8 of lactation (P < 0.05). Group L milk lipid concentration also increased between days 4 and 8 of lactation (P < 0.05). Milk Na concentration declined during lactation in both dietary groups (P < 0.01) but was unaffected by dietary treatment. Both milk Ca and P concentrations increased (P < 0.01) during lactation in both dietary groups, whilst protein restriction also

  1. PTHrP regulates the modeling of cortical bone surfaces at fibrous insertion sites during growth.

    PubMed

    Wang, Meina; VanHouten, Joshua N; Nasiri, Ali R; Johnson, Randy L; Broadus, Arthur E

    2013-03-01

    The sites that receive ligament and tendon insertions (entheses) on the cortical surfaces of long bones are poorly understood, particularly regarding modeling and regulation. Entheses are classified as either fibrocartilaginous or fibrous based on their structures. Fibrous entheses typically insert into the metaphysis or diaphysis of a long bone, bear a periosteal component, and are modeled during long-bone growth. This modeling forms a root system by which the insertions attach to the cortical surface. In the case of the medial collateral ligament, modeling drives actual migration of the ligament along the cortical surface in order to accommodate linear growth, whereas in other sites modeling may excavate a deep cortical root system (eg, the teres major insertion) or a shallow root system with a large footprint (eg, the latissimus dorsi insertion). We report here that conditionally deleting parathyroid hormone-related protein (PTHrP) in fibrous entheses via Scleraxis-Cre targeting causes modeling to fail in these three iterations of osteoclast-driven enthesis excavation or migration. These iterations appear to represent formes frustes of a common modeling strategy, presumably differing from each other as a consequence of differences in biomechanical control. In sites in which PTHrP is not induced, either physiologically or because of conditional deletion, modeling does not take place and fibrocartilage is induced. These findings represent the initial genetic evidence that PTHrP regulates periosteal/intramembranous bone cell activity on cortical bone surfaces and indicate that PTHrP serves as a load-induced modeling tool in fibrous insertion sites during linear growth. PMID:23109045

  2. Energy and protein needs of cats for maintenance, gestation and lactation.

    PubMed

    Wichert, B; Schade, L; Gebert, S; Bucher, B; Zottmaier, B; Wenk, C; Wanner, M

    2009-10-01

    In the present investigation, data on the energy intakes and energy needs, as well as protein and fat accretion, of queens during pregnancy, during lactation and after lactation are given. Eleven adult cats were used as experimental animals. Data were collected during the fourth and seventh week of pregnancy, the second and sixth week of lactation and the second and sixth week after lactation. The cats were fed dry kitten food. During gestation and after lactation, all measurements were performed with respiration chambers. During lactation, balance trials without respiration chambers were performed. Body weight was measured and nitrogen, carbon and energy balances were calculated. From these, protein and fat accretion, as well as the metabolisable energy intake, was calculated. The weight gain during gestation was linearly independent of the number of kittens. During lactation, all cats lost weight; nevertheless, all cats except one were heavier 2 weeks after lactation than at mating. The energy intake of the cats during gestation was 1.8 times the maintenance requirement in the fourth week and two times maintenance requirement in the seventh week, and these energy intakes differed greatly among individuals. The energy intake of the cats during lactation was clearly higher than that recommended by National Research Council (NRC)(1), whereas the recommended protein intake in the second week of lactation was met. As the calculated protein balance was negative, the NRC recommendation for protein intake seems to be too low. In comparison to previous data, the cats showed a higher energy intake during lactation (median 502kJ/kgBW/d, second week lactation), and the weight loss was much lower. Further investigations on pregnant and lactating cats are necessary to complete the database. PMID:19564126

  3. Interaction of protein percent with caloric density and protein source for lactating cows.

    PubMed

    Van Horn, H H; Blanco, O; Harris, B; Beede, D K

    1985-07-01

    Experiment 1 was to test effect of three ratios of energy to protein in complete mixed diets for 36 lactating cows in three, 28-d periods. Energy was varied with cottonseed hulls, pelleted ground corrugated boxes, and a mixture of the two. Crude protein was varied with soybean meal to give energy:crude protein of 5.7, 5.0, and 4.6 for each energy amount. Cottonseed meal was compared with soybean meal in corrugated box diets. Feed intake was much higher with cottonseed hulls, and appreciable feedlot bloat resulted from pelleted ground corrugated box diets. Data adjusted to equal feed intake showed significant effect of energy to crude protein ratio on milk yield and improved digestion of organic matter with soybean meal vs. cottonseed meal. Experiment 2 tested the hypothesis that lactating cows consuming high-protein alfalfa may benefit from supplemental protein. Diets were 50% forage. Six diets were 14 or 18% crude protein in three ratios of alfalfa hay to corn silage (0:100, 50:50, 100:0). Additional corn silage diets were to compare: 14 versus 18% protein from distiller's dried grains with solubles only and with .5 or .9% urea (four diets); two 14% protein diets compared .6% added potassium chloride with or without .5% urea. Thirty-six Holstein cows in early lactation received one of the 12 diets in each of three 28-d periods. Distiller's grains with solubles markedly depressed milk yield (2.2 kg/d) and milk protein (.22%); heat damage of distiller's grains was evident. Protein interacted with alfalfa so gain in milk from 18 versus 14% increased from .55 to 1.36 to 2.66 kg/d as alfalfa changed from 0 to 50 to 100%. Thus, crude protein of alfalfa was not as effective as that from soybean meal in supporting milk yield. PMID:3839804

  4. Effects of amounts and degradability of dietary protein on lactation, nitrogen utilization, and excretion in early lactation Holstein cows.

    PubMed

    Davidson, S; Hopkins, B A; Diaz, D E; Bolt, S M; Brownie, C; Fellner, V; Whitlow, L W

    2003-05-01

    Five treatment diets varying in crude protein (CP) and rumen undegradable protein (RUP) were calculated to supply a postruminal lysine to methionine ratio of about 3:1. Diets were fed as a total mixed ration to 65 Holstein cows that were either primiparous (n = 28) or multiparous (n = 37) from 21 to 120 d in milk to determine effects on lactation and nitrogen utilization. Crude protein % and calculated RUP (% of CP) of diets [on a dry matter (DM) basis] were: 1) 19.4, 40 (HPMU), 2) 16.5, 34 (LPLU), 3) 16.8, 40 (LPMU), 4) 16.8, 46 (LPHU), 5) 17.2, 43 (LPHU + UREA), which is the result of adding 0.4% of the diet DM as urea to LPHU. The corn silage-based treatment diets contained an average of 24% acid detergent fiber and 1.6 Mcal/kg net energy of lactation. Milk urea nitrogen (MUN) concentrations and body weights (BW) were used to calculate predicted amounts of urinary nitrogen (N) using the relationship: urinary N (g/d) = 0.0259 x BW (kg) x MUN (mg/dl). Cows fed HPMU had greater CP and RUP intakes, which resulted in higher concentrations of plasma urea nitrogen, rumen ammonia, MUN, and predicted urinary N. Milk yield, fat yield, fat percent, protein yield, and protein percent were not significantly different among treatments. Parity primarily affected parameters that were related to body size and not measurements of N utilization. The interaction of treatment and parity was not significant for any measurements taken. In this study, cows fed LPHU had significantly lower MUN and predicted urinary N without limiting production. These results demonstrate the potential to optimize milk production while minimizing N excretion in lactating dairy cattle. PMID:12778579

  5. A case of adenosquamous cell carcinoma of the gallbladder with markedly elevated PTHrP and G-CSF levels.

    PubMed

    Ueda, Kaoru; Kinoshita, Akiyoshi; Akasu, Takafumi; Hagiwara, Noriko; Yokota, Takeharu; Imai, Nami; Iwaku, Akira; Fushiya, Nao; Koike, Kazuhiko; Nishino, Hirokazu

    2016-09-01

    A 76-year-old woman was referred to our hospital with anorexia. Computed tomography revealed a tumor lesion measuring 110mm in the liver at S4/5 with calcification and swelling of a paraaortic lymph node. The gallbladder was not visualized. Histological examination of a biopsy specimen from the liver tumor revealed squamous cell and undifferentiated carcinomas, and several tumor markers were elevated. Therefore, we diagnosed the patient with gallbladder adenosquamous cell carcinoma T3N2M0 stage III. Because the serum parathyroid hormone-related protein (PTHrP) and granulocyte-colony stimulating factor (G-CSF) levels were significantly elevated, we suspected that PTHrP and G-CSF production occurred because of adenosquamous cell carcinoma in the gallbladder. We initiated chemotherapy with S-1. PMID:27593366

  6. Automated High Throughput Protein Crystallization Screening at Nanoliter Scale and Protein Structural Study on Lactate Dehydrogenase

    SciTech Connect

    Fenglei Li

    2006-08-09

    The purposes of our research were: (1) To develop an economical, easy to use, automated, high throughput system for large scale protein crystallization screening. (2) To develop a new protein crystallization method with high screening efficiency, low protein consumption and complete compatibility with high throughput screening system. (3) To determine the structure of lactate dehydrogenase complexed with NADH by x-ray protein crystallography to study its inherent structural properties. Firstly, we demonstrated large scale protein crystallization screening can be performed in a high throughput manner with low cost, easy operation. The overall system integrates liquid dispensing, crystallization and detection and serves as a whole solution to protein crystallization screening. The system can dispense protein and multiple different precipitants in nanoliter scale and in parallel. A new detection scheme, native fluorescence, has been developed in this system to form a two-detector system with a visible light detector for detecting protein crystallization screening results. This detection scheme has capability of eliminating common false positives by distinguishing protein crystals from inorganic crystals in a high throughput and non-destructive manner. The entire system from liquid dispensing, crystallization to crystal detection is essentially parallel, high throughput and compatible with automation. The system was successfully demonstrated by lysozyme crystallization screening. Secondly, we developed a new crystallization method with high screening efficiency, low protein consumption and compatibility with automation and high throughput. In this crystallization method, a gas permeable membrane is employed to achieve the gentle evaporation required by protein crystallization. Protein consumption is significantly reduced to nanoliter scale for each condition and thus permits exploring more conditions in a phase diagram for given amount of protein. In addition

  7. Identification of lactate dehydrogenase as a mammalian pyrroloquinoline quinone (PQQ)-binding protein

    PubMed Central

    Akagawa, Mitsugu; Minematsu, Kenji; Shibata, Takahiro; Kondo, Tatsuhiko; Ishii, Takeshi; Uchida, Koji

    2016-01-01

    Pyrroloquinoline quinone (PQQ), a redox-active o-quinone, is an important nutrient involved in numerous physiological and biochemical processes in mammals. Despite such beneficial functions, the underlying molecular mechanisms remain to be established. In the present study, using PQQ-immobilized Sepharose beads as a probe, we examined the presence of protein(s) that are capable of binding PQQ in mouse NIH/3T3 fibroblasts and identified five cellular proteins, including l-lactate dehydrogenase (LDH) A chain, as potential mammalian PQQ-binding proteins. In vitro studies using a purified rabbit muscle LDH show that PQQ inhibits the formation of lactate from pyruvate in the presence of NADH (forward reaction), whereas it enhances the conversion of lactate to pyruvate in the presence of NAD+ (reverse reaction). The molecular mechanism underlying PQQ-mediated regulation of LDH activity is attributed to the oxidation of NADH to NAD+ by PQQ. Indeed, the PQQ-bound LDH oxidizes NADH, generating NAD+, and significantly catalyzes the conversion of lactate to pyruvate. Furthermore, PQQ attenuates cellular lactate release and increases intracellular ATP levels in the NIH/3T3 fibroblasts. Our results suggest that PQQ, modulating LDH activity to facilitate pyruvate formation through its redox-cycling activity, may be involved in the enhanced energy production via mitochondrial TCA cycle and oxidative phosphorylation. PMID:27230956

  8. PTHrP(1-34)-mediated repression of the PHEX gene in osteoblastic cells involves the transcriptional repressor E4BP4.

    PubMed

    Pellicelli, Martin; Taheri, Maryam; St-Louis, Mathieu; Bériault, Véronique; Desgroseillers, Luc; Boileau, Guy; Moreau, Alain

    2012-06-01

    PHosphate-regulating gene with homology to Endopeptidase on the X chromosome (PHEX) has been identified as the gene mutated in X-linked hypophosphatemia (XLH) syndrome, the most prevalent form of rickets in humans. The predominant expression of PHEX in bones and teeth, and the defective mineralization of these tissues in XLH patients indicate that PHEX is an important regulator of mineralization. Parathyroid hormone (PTH) and PTH-related protein (PTHrP) are known to regulate the expression of numerous genes in osteoblastic cells through activation of the protein kinase A pathway, including repression of PHEX. PTH also activates the transcriptional repressor E4BP4 through the same pathway, suggesting that PTH or PTHrP-mediated repression of PHEX expression could involve E4BP4. To evaluate this possibility, we treated UMR-106 osteoblastic cells with PTHrP(1-34), and used RT-PCR and immunoblotting to analyze PHEX and E4BP4 expression. E4BP4 mRNA and protein levels were rapidly increased in cells treated with PTHrP(1-34), with a concomitant decrease in PHEX expression. This downregulation of PHEX could be reproduced by overexpression of E4BP4. Moreover, PTHrP(1-34)-mediated PHEX repression was blocked when cells were transfected with a siRNA targeting E4BP4 mRNA. Finally, DNA pull-down and luciferase assays showed that two E4BP4 response elements located in PHEX promoter were functional. These results underline the important role of E4BP4 in osteoblastic cells and further define the repression mechanism of PHEX gene by PTHrP(1-34). PMID:21826652

  9. Effect of dietary protein content on animal production and blood metabolites of dairy cows during lactation.

    PubMed

    Law, R A; Young, F J; Patterson, D C; Kilpatrick, D J; Wylie, A R G; Mayne, C S

    2009-03-01

    Ninety autumn-calving Holstein dairy cows [45 primiparous and 45 multiparous (mean parity, 3.1)] were allocated to 1 of 3 dietary crude protein (CP) concentrations: 173, 144, or 114 g of CP/kg of DM, from calving until d 150 of lactation. On d 151, half of the animals in each treatment were allocated an alternative dietary protein concentration. Half of the animals receiving 114 g of CP/kg of DM went onto 144 g of CP/kg of DM; half of the animals receiving 144 g of CP/kg of DM went onto 173 g of CP/kg of DM; and half of the animals receiving 173 g of CP/kg of DM went onto 144 g of CP/kg of DM, with the remaining animals staying on their original treatment. This resulted in 6 treatments in the mid to late lactation period: 114/114, 144/144, 173/173, 114/144, 144/173, and 173/144 g of CP/kg of DM. An increase in dietary CP concentration significantly increased milk, fat, and protein yield in early lactation (d 1 to 150). Dry matter intake was also increased with increased dietary protein concentration; however, this was not significant between 144 and 173 g of CP/kg of DM. Increased dietary CP significantly increased plasma urea, albumin, and total protein concentrations but had no significant effect on NEFA, leptin, or IGF-1 concentrations. Decreasing the dietary CP concentration in mid-late lactation (d 151 to 305) from 173 to 144 g/kg of DM had no significant effect on milk yield, dry matter intake, or milk fat and protein yield, compared with animals that remained on 173 g of CP/kg of DM throughout lactation. Increasing dietary CP concentration from 144 to 173 g/kg of DM significantly increased dry matter intake compared with animals that remained on the 144 g of CP/kg of DM throughout lactation. There were no significant dietary treatment effects on live weight or body condition score change throughout the experiment. Results of this study indicate that high protein diets (up to 173 g of CP/kg of DM) improved feed intake and animal performance in early lactation

  10. CHALLENGES IN UTILIZATION OF HIGH PROTEIN FORAGES BY LACTATING DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forages are good for the environment and cow health. However, forages of sufficient quality often have elevated levels of rumen-degraded protein (RDP), much of which is converted to ammonia by ruminal microorganisms and excreted as urea. As a result, efficiency of N utilization by lactating cows fed...

  11. Effects of Different Protein Supplements on Milk Production and Nutrient Utilization in Lactating Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sixteen (8 ruminally cannulated) multiparous and 8 primiparous lactating Holstein cows were used in 6 replicated 4 x 4 Latin squares to test the effects of feeding supplemental protein as urea, solvent soybean meal (SSBM), cottonseed meal (CSM), or canola meal (CM) on milk production, nutrient utili...

  12. Carbohydrate Source and Protein Degradability Alter Lactation, Ruminal, and Blood Measures.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of nonfiber carbohydrate source (NFC) and protein degradability (RDP) in the diets of lactating dairy cattle on intake, production, efficiency, and ruminal measures were evaluated in a three period (21 d) partially balanced incomplete latin square design with a 3x2 factorial arrangement of t...

  13. EFFECTS OF VARYING DIETARY PROTEIN AND ENERGY LEVELS ON THE PRODUCTION OF LACTATING DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forty-five multiparous and 18 primiparous Holstein cows averaging 41 kg/d of milk were fed three levels of crude protein (CP), each at three levels of neutral detergent fiber (NDF), to identify optimal dietary CP and energy. Cows were blocked by lactation and days in milk into seven groups of nine a...

  14. Comparative 2D-DIGE Proteomic Analysis of Bovine Mammary Epithelial Cells during Lactation Reveals Protein Signatures for Lactation Persistency and Milk Yield

    PubMed Central

    Janjanam, Jagadeesh; Singh, Surender; Jena, Manoj K.; Varshney, Nishant; Kola, Srujana; Kumar, Sudarshan; Kaushik, Jai K.; Grover, Sunita; Dang, Ajay K.; Mukesh, Manishi; Prakash, B. S.; Mohanty, Ashok K.

    2014-01-01

    Mammary gland is made up of a branching network of ducts that end with alveoli which surrounds the lumen. These alveolar mammary epithelial cells (MEC) reflect the milk producing ability of farm animals. In this study, we have used 2D-DIGE and mass spectrometry to identify the protein changes in MEC during immediate early, peak and late stages of lactation and also compared differentially expressed proteins in MEC isolated from milk of high and low milk producing cows. We have identified 41 differentially expressed proteins during lactation stages and 22 proteins in high and low milk yielding cows. Bioinformatics analysis showed that a majority of the differentially expressed proteins are associated in metabolic process, catalytic and binding activity. The differentially expressed proteins were mapped to the available biological pathways and networks involved in lactation. The proteins up-regulated during late stage of lactation are associated with NF-κB stress induced signaling pathways and whereas Akt, PI3K and p38/MAPK signaling pathways are associated with high milk production mediated through insulin hormone signaling. PMID:25111801

  15. Comparative 2D-DIGE proteomic analysis of bovine mammary epithelial cells during lactation reveals protein signatures for lactation persistency and milk yield.

    PubMed

    Janjanam, Jagadeesh; Singh, Surender; Jena, Manoj K; Varshney, Nishant; Kola, Srujana; Kumar, Sudarshan; Kaushik, Jai K; Grover, Sunita; Dang, Ajay K; Mukesh, Manishi; Prakash, B S; Mohanty, Ashok K

    2014-01-01

    Mammary gland is made up of a branching network of ducts that end with alveoli which surrounds the lumen. These alveolar mammary epithelial cells (MEC) reflect the milk producing ability of farm animals. In this study, we have used 2D-DIGE and mass spectrometry to identify the protein changes in MEC during immediate early, peak and late stages of lactation and also compared differentially expressed proteins in MEC isolated from milk of high and low milk producing cows. We have identified 41 differentially expressed proteins during lactation stages and 22 proteins in high and low milk yielding cows. Bioinformatics analysis showed that a majority of the differentially expressed proteins are associated in metabolic process, catalytic and binding activity. The differentially expressed proteins were mapped to the available biological pathways and networks involved in lactation. The proteins up-regulated during late stage of lactation are associated with NF-κB stress induced signaling pathways and whereas Akt, PI3K and p38/MAPK signaling pathways are associated with high milk production mediated through insulin hormone signaling. PMID:25111801

  16. Effects of Different Protein Supplements on Omasal Nutrient Flow and Microbial Protein Synthesis in Lactating Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eight ruminally cannulated Holstein cows that were part of a larger lactation trial were used in 2 replicated 4 x 4 Latin squares to quantify effects of supplementing protein as urea, solvent soybean meal (SSBM), cottonseed meal (CSM), or canola meal (CM) on omasal nutrient flows and microbial prote...

  17. Reproductive and Metabolic Responses of Early-lactating Dairy Cows Fed Different Dietary Protein Sources.

    PubMed

    Tufarelli, V; Lacalandra, G M; Laudadio, V

    2015-10-01

    Optimal reproduction is very closely tied with optimal nutrition, and early-lactation diets in cows are critical to successful reproduction and monitoring is important. To evaluate the effects of different dietary protein sources on metabolic parameters and reproductive activity, a total of 36 Italian Friesian early-lactating dairy cows were assigned for 16 weeks to three dietary treatments as follow: the control diet contained soya bean meal (SBM) as the main protein source, whereas the experimental diets contained faba bean (FB) or pea seeds (PS) as alternative protein sources. Diets were formulated to be isocaloric and isonitrogenous. Cow blood samples were collected, and plasma were analysed for metabolites, biological enzymes, β-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA). Feeding alternative protein sources had no effects on most metabolic blood profile, except for blood cholesterol, triglycerides and urea. Results from reproductive parameters indicated that cows fed FB diet had a lower insemination index, but a shorter calving to conception period and an improved conception rate and artificial insemination outcome, when compared to cows fed SBM or PS diets. It can be concluded that replacing conventional dietary SBM with alternative protein sources, especially FB, resulted in improved reproductive performances and metabolic parameters in early-lactating dairy cows. PMID:26134899

  18. Nitrogen Metabolism in Lactating Goats Fed with Diets Containing Different Protein Sources

    PubMed Central

    Santos, A. B.; Pereira, M. L. A.; Silva, H. G. O.; Pedreira, M. S.; Carvalho, G. G. P.; Ribeiro, L. S. O.; Almeida, P. J. P.; Pereira, T. C. J.; Moreira, J. V.

    2014-01-01

    This study aimed to evaluate urea excretion, nitrogen balance and microbial protein synthesis in lactating goats fed with diets containing different protein sources in the concentrate (soybean meal, cottonseed meal, aerial part of cassava hay and leucaena hay). Four Alpine goats whose mean body weight was 42.6±6.1 kg at the beginning of the experiment, a mean lactation period of 94.0±9.0 days and a production of 1.7±0.4 kg of milk were distributed in a 4×4 Latin square with four periods of 15 days. Diets were formulated to be isonitrogenous, containing 103.0 g/kg of CP, 400 g/kg of Tifton 85 hay and 600 g/kg of concentrate. Diet containing cottonseed meal provided (p<0.05) increased excretion of urea and urea nitrogen in the urine (g/d and mg/kg of BW) when compared with leucaena hay. The diets affected the concentrations of urea nitrogen in plasma (p<0.05) and excretion of urea nitrogen in milk, being that soybean meal and cottonseed meal showed (p<0.05) higher than the average aerial part of the cassava hay. The use of diets with cottonseed meal as protein source in the concentrate in feeding of lactating goats provides greater nitrogen excretion in urine and negative nitrogen balance, while the concentrate with leucaena hay as a source of protein, provides greater ruminal microbial protein synthesis. PMID:25050000

  19. Secretion of whey acidic protein and cystatin is down regulated at mid-lactation in the red kangaroo (Macropus rufus)

    USGS Publications Warehouse

    Nicholas, K.R.; Fisher, J.A.; Muths, E.; Trott, J.; Janssens, P.A.; Reich, C.; Shaw, D.C.

    2001-01-01

    Milk collected from the red kangaroo (Macropus rufus) between day 100 and 260 of lactation showed major changes in milk composition at around day 200 of lactation, the time at which the pouch young begins to temporarily exit the pouch and eat herbage. The carbohydrate content of milk declined abruptly at this time and although there was only a small increase in total protein content, SDS PAGE analysis of milk revealed asynchrony in the secretory pattern of individual proteins. The levels of ??-lactalbumin, ??-lactoglobulin, serum albumin and transferrin remain unchanged during lactation. In contrast, the protease inhibitor cystatin, and the putative protease inhibitor whey acidic protein (WAP) first appeared in milk at elevated concentrations after approximately 150 days of lactation and then ceased to be secreted at approximately 200 days. In addition, a major whey protein, late lactation protein, was first detected in milk around the time whey acidic protein and cystatin cease to be secreted and was present at least until day 260 of lactation. The co-ordinated, but asynchronous secretion of putative protease inhibitors in milk may have several roles during lactation including tissue remodelling in the mammary gland and protecting specific proteins in milk required for physiological development of the dependent young. ?? 2001 Elsevier Science Inc.

  20. Monotreme Lactation Protein Is Highly Expressed in Monotreme Milk and Provides Antimicrobial Protection

    PubMed Central

    Enjapoori, Ashwantha Kumar; Grant, Tom R.; Nicol, Stewart C.; Lefèvre, Christophe M.; Nicholas, Kevin R.; Sharp, Julie A.

    2014-01-01

    Monotremes (platypus and echidna) are the descendants of the oldest ancestor of all extant mammals distinguished from other mammals by mode of reproduction. Monotremes lay eggs following a short gestation period and after an even briefer incubation period, altricial hatchlings are nourished over a long lactation period with milk secreted by nipple-less mammary patches located on the female’s abdomen. Milk is the sole source of nutrition and immune protection for the developing young until weaning. Using transcriptome and mass spectrometry analysis of milk cells and milk proteins, respectively, a novel Monotreme Lactation Protein (MLP) was identified as a major secreted protein in milk. We show that platypus and short-beaked echidna MLP genes show significant homology and are unique to monotremes. The MLP transcript was shown to be expressed in a variety of tissues; however, highest expression was observed in milk cells and was expressed constitutively from early to late lactation. Analysis of recombinant MLP showed that it is an N-linked glycosylated protein and biophysical studies predicted that MLP is an amphipathic, α-helical protein, a typical feature of antimicrobial proteins. Functional analysis revealed MLP antibacterial activity against both opportunistic pathogenic Staphylococcus aureus and commensal Enterococcus faecalis bacteria but showed no effect on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Salmonella enterica. Our data suggest that MLP is an evolutionarily ancient component of milk-mediated innate immunity absent in other mammals. We propose that MLP evolved specifically in the monotreme lineage supporting the evolution of lactation in these species to provide bacterial protection, at a time when mammals lacked nipples. PMID:25245409

  1. Monotreme lactation protein is highly expressed in monotreme milk and provides antimicrobial protection.

    PubMed

    Enjapoori, Ashwantha Kumar; Grant, Tom R; Nicol, Stewart C; Lefèvre, Christophe M; Nicholas, Kevin R; Sharp, Julie A

    2014-10-01

    Monotremes (platypus and echidna) are the descendants of the oldest ancestor of all extant mammals distinguished from other mammals by mode of reproduction. Monotremes lay eggs following a short gestation period and after an even briefer incubation period, altricial hatchlings are nourished over a long lactation period with milk secreted by nipple-less mammary patches located on the female's abdomen. Milk is the sole source of nutrition and immune protection for the developing young until weaning. Using transcriptome and mass spectrometry analysis of milk cells and milk proteins, respectively, a novel Monotreme Lactation Protein (MLP) was identified as a major secreted protein in milk. We show that platypus and short-beaked echidna MLP genes show significant homology and are unique to monotremes. The MLP transcript was shown to be expressed in a variety of tissues; however, highest expression was observed in milk cells and was expressed constitutively from early to late lactation. Analysis of recombinant MLP showed that it is an N-linked glycosylated protein and biophysical studies predicted that MLP is an amphipathic, α-helical protein, a typical feature of antimicrobial proteins. Functional analysis revealed MLP antibacterial activity against both opportunistic pathogenic Staphylococcus aureus and commensal Enterococcus faecalis bacteria but showed no effect on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Salmonella enterica. Our data suggest that MLP is an evolutionarily ancient component of milk-mediated innate immunity absent in other mammals. We propose that MLP evolved specifically in the monotreme lineage supporting the evolution of lactation in these species to provide bacterial protection, at a time when mammals lacked nipples. PMID:25245409

  2. Negative regulation of parathyroid hormone-related protein expression by steroid hormones

    SciTech Connect

    Kajitani, Takashi; Tamamori-Adachi, Mimi; Okinaga, Hiroko; Chikamori, Minoru; Iizuka, Masayoshi; Okazaki, Tomoki

    2011-04-15

    Highlights: {yields} Steroid hormones repress expression of PTHrP in the cell lines where the corresponding nuclear receptors are expressed. {yields} Nuclear receptors are required for suppression of PTHrP expression by steroid hormones, except for androgen receptor. {yields} Androgen-induced suppression of PTHrP expression appears to be mediated by estrogen receptor. -- Abstract: Elevated parathyroid hormone-related protein (PTHrP) is responsible for humoral hypercalcemia of malignancy (HHM), which is of clinical significance in treatment of terminal patients with malignancies. Steroid hormones were known to cause suppression of PTHrP expression. However, detailed studies linking multiple steroid hormones to PTHrP expression are lacking. Here we studied PTHrP expression in response to steroid hormones in four cell lines with excessive PTHrP production. Our study established that steroid hormones negatively regulate PTHrP expression. Vitamin D receptor, estrogen receptor {alpha}, glucocorticoid receptor, and progesterone receptor, were required for repression of PTHrP expression by the cognate ligands. A notable exception was the androgen receptor, which was dispensable for suppression of PTHrP expression in androgen-treated cells. We propose a pathway(s) involving nuclear receptors to suppress PTHrP expression.

  3. Lactate dehydrogenase X, malate dehydrogenase and total protein in rat spermatozoa during epididymal transit.

    PubMed

    Vermouth, N T; Carriazo, C S; Ponce, R H; Blanco, A

    1986-01-01

    Lactate dehydrogenase isozyme X (LDH X), malate dehydrogenase (MDH) and total soluble protein have been determined in lysates of spermatozoa isolated from caput, corpus and cauda of rat epididymis. Transit of spermatozoa through epididymis is accompanied by a reduction of LDH X, MDH and total protein per cell in sexually rested animals. The profiles of reduction along epididymal segments are different for the three variables studied. Mating with receptive females during the 5 days prior to determinations increases significantly the levels of MDH in spermatozoa from all sections of epididymis and produces increase of total soluble protein in the cells contained in cauda. PMID:3956158

  4. Protein quality and quantity and insulin control of mammary gland glucose utilization during lactation

    SciTech Connect

    Masor, M.L.

    1987-01-01

    Virgin Sprague-Dawley rats were bred, and fed laboratory stock (STOCK), 13% casein plus methionine, 13% wheat gluten, or 5% casein plus methionine through gestation and 4 days of lactation. Diets were switched at parturition to determine the effects of dietary protein quality and quantity fed during gestation and/or lactation on insulin stimulation of mammary glucose utilization. On day 20 of gestation (20G) and day 4 of lactation (4L) the right inguinal-abdominal mammary glands were removed, and acini and tissue slices were incubated in Krebs buffer with or without insulin containing (U-/sup 14/C)-glucose and 5mM glucose for 1 hour at 37/degrees/C. Glucose incorporation into CO/sub 2/, lipid and lactose was determined. Glucose incorporation into CO/sub 2/ and lipid, but not lactose was stimulated by insulin in mammary slices. Diet effects on glucose utilization in acini were confirmed in slices for basal and insulin stimulated levels. Treatment affected the absolute increase of insulin stimulation. Regression analysis significantly correlated pup weight gain with total glucose utilization. Poor dietary protein quality and quantity fed during gestation impaired both overall response of mammary glucose utilization to insulin stimulation, and mammary development during pregnancy. Improving protein value at parturition did not overcome those deficits by 4L.

  5. Blood-derived proteins in milk at start of lactation: Indicators of active or passive transfer.

    PubMed

    Wall, Samantha K; Gross, Josef J; Kessler, Evelyne C; Villez, Kris; Bruckmaier, Rupert M

    2015-11-01

    Colostrum has a different composition compared with milk in established lactation. This difference is in part due to the partially open blood-milk barrier, which, when closed, is designed to prevent the interdiffusion of blood and milk components. In the first days of lactation, α-lactalbumin (α-LA), a milk protein, is typically present in blood and several blood-derived proteins are also present in milk, such as IgG1, IgG2, serum albumin (SA), and lactate dehydrogenase (LDH). With the exception of IgG1, which is known to be transferred by active transcellular transport, the other proteins are thought to pass paracellularly through the temporarily open barrier. Along with an exchange of blood and milk components, somatic cell count (SCC) is typically high in colostrum. The decline of these proteins and SCC can be used as indicators to determine transcellular or paracellular transport. Two hypotheses were tested. The first hypothesis was that the decline curve for a protein or SCC would be the same as IgG1, indicating transcellular transport, or the decline curve would be different than IgG1, indicating paracellular transport. The second hypothesis was that the decline curves of SCC and all proteins that are thought to have paracellular transport would be the same. Ten Holstein cows were milked at 4 h after parturition, the next 5 consecutive milkings, and the afternoon milking on d 5, 8, 10, and 14 of lactation for a total of 10 milking time points, and sequential jugular blood samples were also taken. Blood and milk samples were analyzed for the concentrations of LDH, SA, IgG1, IgG2, and α-LA and milk samples were measured for SCC. Protein concentration and SCC curves were generated from all 10 time points and were evaluated using the tau time constant model to determine the rate of decline of the slope of each protein. When examining the first hypothesis, the concentration of IgG1 declined significantly faster in the milk than the proteins IgG2 and LDH, but

  6. Genes regulating lipid and protein metabolism are highly expressed in mammary gland of lactating dairy goats.

    PubMed

    Shi, Hengbo; Zhu, Jiangjiang; Luo, Jun; Cao, Wenting; Shi, Huaiping; Yao, Dawei; Li, Jun; Sun, Yuting; Xu, Huifen; Yu, Kang; Loor, Juan J

    2015-05-01

    Dairy goats serve as an important source of milk and also fulfill agricultural and economic roles in developing countries. Understanding the genetic background of goat mammary gland is important for research on the regulatory mechanisms controlling tissue function and the synthesis of milk components. We collected tissue at four different stages of goat mammary gland development and generated approximately 25 GB of data from Illumina de novo RNA sequencing. The combined reads were assembled into 51,361 unigenes, and approximately 60.07 % of the unigenes had homology to other proteins in the NCBI non-redundant protein database (NR). Functional classification through eukaryotic Ortholog Groups of Protein (KOG), gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that the unigenes from goat mammary glands are involved in a wide range of biological processes and metabolic pathways, including lipid metabolism and lactose metabolism. The results of qPCR revealed that genes encoding FABP3, FASN, SCD, PLIN2, whey proteins (LALBA and BLG), and caseins (CSN1S1, CSN1S2, CSN2 and CSN3) at 100 and 310 days postpartum increased significantly compared with the non-lactating period. In addition to their role in lipid and protein synthesis, the higher expression at 310 days postpartum could contribute to mammary cell turnover during pregnancy. In conclusion, this is the first study to characterize the complete transcriptome of goat mammary glands and constitutes a comprehensive genomic resource available for further studies of ruminant lactation. PMID:25433708

  7. Effects of PTHrP on chondrocytes of sika deer antler.

    PubMed

    Guo, Bin; Wang, Shou-Tang; Duan, Cui-Cui; Li, Dang-Dang; Tian, Xue-Chao; Wang, Qu-Yuan; Yue, Zhan-Peng

    2013-11-01

    Parathyroid-hormone-related peptide (PTHrP) is an important regulator of chondrocyte differentiation in growth plates but little is known about its role in deer antler cartilage. The aim of the present study was to use the deer antler as a model to determine the possible role of PTHrP in regulating chondrocyte differentiation of deer antler. PTHrP and its receptor PTH1R mRNA were highly expressed in the perichondrium and cartilage of sika deer antler, as shown by in situ hybridization. Chondrocytes of deer antler were identified by toluidine blue staining of glycosaminoglycan and immunocytochemical staining of type II collagen (Col II). Treatment with PTHrP (1-34) reduced the expression of prehypertrophic chondrocyte marker Col IX and hypertrophic chondrocyte marker Col X. In order to confirm the mechanism of action of PTHrP, we initially examined the expression of cyclin D1, Bcl-2 and runt-related transcription factor 2 (Runx2) in sika deer antler by in situ hybridization and found that cyclin D1, Runx2 and Bcl-2 mRNA were also expressed in antler chondrocytes. Exogenous PTHrP induced the expression of cyclin D1 and Bcl-2 mRNA by various signalling pathways, whereas it inhibited Runx2 expression through PKA, p38MAPK, MEK and PI3K signalling pathways. Thus, PTHrP might promote the proliferation of antler chondrocytes and prevent their differentiation; it might furthermore influence the growth and development of sika deer antler. PMID:23824099

  8. Feeding supplemental fat and undegraded intake protein to early lactation dairy cows.

    PubMed

    Hoffman, P C; Grummer, R R; Shaver, R D; Broderick, G A; Drendel, T R

    1991-10-01

    Forty-eight Holstein cows (16 primiparous) were fed alfalfa silage-based TMR containing 18% CP with 33 or 36% of the CP as undegraded intake protein and with 0 or 2.8% supplemental fat (DM basis). Expeller soybean meal replaced solvent soybean meal to vary undegraded intake protein, and sodium alginate-treated tallow was used as the fat source. A standard diet containing solvent soybean meal without fat was fed during the first 21 d postpartum for covariate adjustment of milk production. A continuous lactation design with 2 x 2 factorial arrangement of treatments was used with supplemental fat and undegraded intake protein as main effects. Feeding supplemental fat increased actual milk (32.9 vs. 31.7 kg/d) but decreased milk protein concentration. Cows fed supplemental fat also had higher BW, and weight gain was significant with time. Increasing undegraded intake protein did not affect milk yield, composition, or component yield. There were no significant interactions between supplemental fat and undegraded intake protein on milk yield or composition. Milk fatty acid composition was not altered by addition of undegraded intake protein, but C6 to C14 fatty acids were reduced by adding supplemental fat. Results do not support the strategy of increasing levels of undegraded intake protein when supplemental fat is fed. Variation in undegraded intake protein content of feed-stuffs appears to be of more importance in ration formulation than interactions between supplemental fat and protein. PMID:1744277

  9. An in vivo characterization of colostrum protein uptake in porcine gut during early lactation.

    PubMed

    Danielsen, Marianne; Pedersen, Lene Juul; Bendixen, Emøke

    2011-01-01

    Understanding the bioactive roles of colostrum proteins has gained much attention, and in particular, their potential use in human and veterinary medicine has been extensively studied. However, studies of bioactivity have mainly been conducted in vitro, but it has not yet been well characterized at the individual protein level which colostrum components are internalized by the intestinal tissue of the neonate. The aim of this study was to characterize the in vivo processing of porcine colostrum in the gastrointestinal tract, and describe which of the potential bioactive proteins can be observed in the small intestinal tissue, and therefore may be functionally important. Using 2D-LC-MS/MS analysis we mapped the proteins in porcine colostrum. The colostrum proteins were then traced in the stomach content, as well as in the small intestinal tissue of 5 piglets suckled for 24h. For comparison, we also mapped the proteins present in the intestinal tissue of a newborn piglet that had not received colostrum. This analysis allowed us to identify the colostrum proteins that are internalized and retained in the tissue from the small intestine, indicating their functional importance. Our studies have shown that in early lactation, some colostrum proteins are protected against proteolytic degradation in the stomach. Furthermore, colostrum proteins with immuno-protective, antimicrobial or other bioactive functions are more prone to uptake in the small intestine than the caseins and beta-lactoglobulin, which are amongst the most abundant in colostrum. PMID:20831910

  10. Identification of proteins interacting with lactate dehydrogenase in claw muscle of the porcelain crab Petrolisthes cinctipes

    PubMed Central

    Cayenne, Andrea P.; Gabert, Beverly; Stillman, Jonathon H.

    2011-01-01

    Biochemical adaptation of enzymes involves conservation of activity, stability and affinity across a wide range of intracellular and environmental conditions. Enzyme adaptation by alteration of primary structure is well known, but the roles of protein-protein interactions in enzyme adaptation are less well understood. Interspecific differences in thermal stability of lactate dehydrogenase (LDH) in porcelain crabs (genus Petrolisthes) are related to intrinsic differences among LDH molecules and by interactions with other stabilizing proteins. Here, we identified proteins that interact with LDH in porcelain crab claw muscle tissue using co-immunoprecipitation, and showed LDH exists in high molecular weight complexes using size exclusion chromatography and Western blot analyses. Co-immunoprecipitated proteins were separated using 2D SDS PAGE and analyzed by LC/ESI using peptide MS/MS. Peptide MS/MS ions were compared to an EST database for Petrolisthes cinctipes to identify proteins. Identified proteins included cytoskeletal elements, glycolytic enzymes, a phosphagen kinase, and the respiratory protein hemocyanin. Our results support the hypothesis that LDH interacts with glycolytic enzymes in a metabolon structured by cytoskeletal elements that may also include the enzyme for transfer of the adenylate charge in glycolytically produced ATP. Those interactions may play specific roles in biochemical adaptation of glycolytic enzymes. PMID:21968246

  11. Modelling lactation curve for milk fat to protein ratio in Iranian buffaloes (Bubalus bubalis) using non-linear mixed models.

    PubMed

    Hossein-Zadeh, Navid Ghavi

    2016-08-01

    The aim of this study was to compare seven non-linear mathematical models (Brody, Wood, Dhanoa, Sikka, Nelder, Rook and Dijkstra) to examine their efficiency in describing the lactation curves for milk fat to protein ratio (FPR) in Iranian buffaloes. Data were 43 818 test-day records for FPR from the first three lactations of Iranian buffaloes which were collected on 523 dairy herds in the period from 1996 to 2012 by the Animal Breeding Center of Iran. Each model was fitted to monthly FPR records of buffaloes using the non-linear mixed model procedure (PROC NLMIXED) in SAS and the parameters were estimated. The models were tested for goodness of fit using Akaike's information criterion (AIC), Bayesian information criterion (BIC) and log maximum likelihood (-2 Log L). The Nelder and Sikka mixed models provided the best fit of lactation curve for FPR in the first and second lactations of Iranian buffaloes, respectively. However, Wood, Dhanoa and Sikka mixed models provided the best fit of lactation curve for FPR in the third parity buffaloes. Evaluation of first, second and third lactation features showed that all models, except for Dijkstra model in the third lactation, under-predicted test time at which daily FPR was minimum. On the other hand, minimum FPR was over-predicted by all equations. Evaluation of the different models used in this study indicated that non-linear mixed models were sufficient for fitting test-day FPR records of Iranian buffaloes. PMID:27600968

  12. Effects of a protein deficient diet and urea supplementation on lactating mares.

    PubMed

    Martin, R G; McMeniman, N P; Dowsett, K F

    1991-01-01

    Six lactating mares were fed either a low protein diet or the same diet with added urea ad libitum over 71 days. The quantity consumed by the mares, milk intakes of their foals, milk composition, plasma urea nitrogen (PUN), mare liveweight changes and foal growth rates were measured. The mares were unable to consume sufficient quantities of either diet to meet their nitrogen requirements and all lost weight. Adding urea to the diet significantly increased PUN in mares and foals, raised urea concentrations in the milk, decreased the mares' feed intake and significantly increased their weight loss. Low concentrations of protein were measured in milk from mares on both diets. Milk intakes of all the foals were reduced and they showed poor growth rates. PMID:1795297

  13. Lactation Affects Isolated Mitochondria and Its Fatty Acid Composition but Has No Effect on Tissue Protein Oxidation, Lipid Peroxidation or DNA-Damage in Laboratory Mice

    PubMed Central

    Valencak, Teresa G.; Raith, Johannes; Staniek, Katrin; Gille, Lars; Strasser, Alois

    2016-01-01

    Linking peak energy metabolism to lifespan and aging remains a major question especially when focusing on lactation in females. We studied, if and how lactation affects in vitro mitochondrial oxygen consumption and mitochondrial fatty acid composition. In addition, we assessed DNA damage, lipid peroxidation and protein carbonyls to extrapolate on oxidative stress in mothers. As model system we used C57BL/6NCrl mice and exposed lactating females to two ambient temperatures (15 °C and 22 °C) while they nursed their offspring until weaning. We found that state II and state IV respiration rates of liver mitochondria were significantly higher in the lactating animals than in non-lactating mice. Fatty acid composition of isolated liver and heart mitochondria differed between lactating and non-lactating mice with higher n-6, and lower n-3 polyunsaturated fatty acids in the lactating females. Surprisingly, lactation did not affect protein carbonyls, lipid peroxidation and DNA damage, nor did moderate cold exposure of 15 °C. We conclude that lactation increases rates of mitochondrial uncoupling and alters mitochondrial fatty acid composition thus supporting the “uncoupling to survive” hypothesis. Regarding oxidative stress, we found no impact of lactation and lower ambient temperature and contribute to growing evidence that there is no linear relationship between oxidative damage and lactation. PMID:26805895

  14. 1,25-dihydroxyvitamin D and PTHrP mediated malignant hypercalcemia in a seminoma

    PubMed Central

    2014-01-01

    Background Seminomas have been rarely associated with malignant hypercalcemia. The responsible mechanism of hypercalcemia in this setting has been described to be secondary to 1,25-dihydroxyvitamin D secretion. The relationship with PTHrP has not been determined or studied. The aim of this study is to describe and discuss the case and the pathophysiological mechanisms involved in a malignant hypercalcemia mediated by 1,25-dihydroxyvitamin D and PTHrP cosecretion in a patient with seminoma. Case presentation A 35-year-old man was consulted for assessment and management of severe hypercalcemia related to an abdominal mass. Nausea, polyuria, polydipsia, lethargy and confusion led him to the emergency department. An abdominal and pelvic enhanced CT confirmed a calcified pelvic mass, along with multiple retroperitoneal lymphadenopathy. Chest x-ray revealed “cannon ball” pulmonary metastases. The histopathology result was consistent with a seminoma. Serum calcium was 14.7 mg/dl, PTH was undetectable, 25-dihydroxyvitamin D was within normal values and PTHrP and 1,25-dihydroxyvitamin were elevated (35.0 pg/ml, and 212 pg/ml, respectively). After the first cycle of chemotherapy with bleomycin, etoposide and cisplatin, normocalcemia was restored. Both PTHrP and 1,25-dihydroxyvitamin D, dropped dramatically to 9.0 pg/ml and 8.0 pg/ml, respectively. Conclusion The association of seminoma and malignant hypercalcemia is extremely rare. We describe a case of a patient with a seminoma and malignant hypercalcemia related to paraneoplastic cosecretion of 1,25-dihydroxyvitamin D and PTHrP. After successful chemotherapy, calcium, PTHrP and 1,25-Dihydroxyvitamin D returned to normal values. PMID:24721620

  15. Thyroid hormone responsive protein Spot14 enhances catalysis of fatty acid synthase in lactating mammary epithelium[S

    PubMed Central

    Rudolph, Michael C.; Wellberg, Elizabeth A.; Lewis, Andrew S.; Terrell, Kristina L.; Merz, Andrea L.; Maluf, N. Karl; Serkova, Natalie J.; Anderson, Steven M.

    2014-01-01

    Thyroid hormone responsive protein Spot 14 has been consistently associated with de novo fatty acid synthesis activity in multiple tissues, including the lactating mammary gland, which synthesizes large quantities of medium chain fatty acids (MCFAs) exclusively via FASN. However, the molecular function of Spot14 remains undefined during lactation. Spot14-null mice produce milk deficient in total triglyceride and de novo MCFA that does not sustain optimal neonatal growth. The lactation defect was rescued by provision of a high fat diet to the lactating dam. Transgenic mice overexpressing Spot14 in mammary epithelium produced total milk fat equivalent to controls, but with significantly greater MCFA. Spot14-null dams have no diminution of metabolic gene expression, enzyme protein levels, or intermediate metabolites that accounts for impaired de novo MCFA. When [13C] fatty acid products were quantified in vitro using crude cytosolic lysates, native FASN activity was 1.6-fold greater in control relative to Spot14-null lysates, and add back of Spot14 partially restored activity. Recombinant FASN catalysis increased 1.4-fold and C = 14:0 yield was enhanced 4-fold in vitro following addition of Spot14. These findings implicate Spot14 as a direct protein enhancer of FASN catalysis in the mammary gland during lactation when maximal MCFA production is needed. PMID:24771867

  16. Lactational responses to ruminally undegradable protein by dairy cows fed diets based on alfalfa silage.

    PubMed

    Wattiaux, M A; Combs, D K; Shaver, R D

    1994-06-01

    Lactational responses to protein supplementation of diets containing 60% of DM as alfalfa silage were evaluated. Sixty muliparous Holstein cows were fed a covariant diet for the first 3 wk postpartum, blocked by calving date, and randomly assigned for 14 wk to one of six isonitrogenous (19.4% CP) diets. Diets were formulated with soybean meal, a blend of animal by-products, or both, and contained 5.0, 5.6, 5.6, 6.2, 6.1, and 6.8% ruminally undegradable protein (DM basis). Percentage of ruminally undegradable protein or source of supplemental protein did not affect 3.5% FCM (39.4 kg/d), milk fat yield (1.38 kg/d), milk protein percentage (2.83%), milk urea (7.66 mM), or plasma urea (8.91 mM). However, cows fed diets supplemented with soybean meal had higher DMI (26.2 vs. 24.7 kg/d), milk yields (40.4 vs. 39.1 kg/d), and milk protein (1.15 vs. 1.09 kg/d) yields, but lower milk fat concentration (3.42 vs. 3.53%) and body condition score (2.85 vs. 2.93) than cows fed diets containing a blend of animal by-products. The lack of response to ruminally undegradable protein was partially caused by higher than predicted DMI (5 to 15% above NRC predictions); all diets provided at least 1.3 kg of ruminally undegradable protein, and there was no beneficial effect from ruminally undegradable protein intake increases to 1.6 kg/d. PMID:8083421

  17. An Herbal Galactagogue Mixture Increases Milk Production and Aquaporin Protein Expression in the Mammary Glands of Lactating Rats

    PubMed Central

    Liu, Haibin; Hua, Ying; Luo, Hui; Shen, Zhaojun; Tao, Xuejiao

    2015-01-01

    Background. Herbal galactagogues have been increasingly used to treat postpartum hypogalactia. The mechanism of action of herbal galactagogues remains unclear. The purpose of this study was to investigate the effect of an herbal galactagogue mixture on milk production and aquaporin (AQP) expression in lactating rats. Methods. Thirty female Sprague Dawley rats were randomized into virgin, lactating + H2O, and lactating + galactagogue groups (n = 10 per group). Lactating rats were administered the decoction of an herbal galactagogue mixture by oral gavage or the same amount of distilled water. Results. The herbal decoction significantly increased milk production in lactating rats (P < 0.05). Both immunohistochemical staining and western blot showed that protein levels of AQP-3 and AQP-5 were significantly increased during lactation compared with virgin stage and the herbal decoction further elevated their expression (P < 0.05). AQP-1 was predominantly expressed in the capillaries whereas AQP-3 and AQP-5 were mainly detected in the epithelial cells and ducts of the mammary glands. Conclusion. The expression of AQPs in the mammary glands of rats was developmentally regulated. Herbal galactagogues might have increased milk secretion by regulating the expression and function of AQPs in the mammary glands. PMID:26075000

  18. Analysis of fluid in cysts accompanying various primary and metastatic brain tumours: proteins, lactate and pH.

    PubMed

    Lohle, P N; Wurzer, H A; Seelen, P J; Kingma, L M; Go, K G

    1998-01-01

    There is a growing interest in cystic lesions of the brain. By examining the cyst content of brain tumours more insight into the pathogenesis of cyst formation has been found. In this study, 39 samples of cyst fluid of 34 patients with a cyst accompanying a brain tumour were collected and studied biochemically regarding their protein content, lactate and pH. In this study we investigated the relation between the grade of malignancy and the lactate-concentration and the discrepancy between the high levels of lactate in cysts and their alkaline environment. The results of the measurements of the concentrations of albumin, immunoglobulines (IgG, IgA, IgM) and alpha 2-macroglobulin in cysts compared to those in sera suggest that cyst formation associated with tumour is based upon a disruption of the blood-brain barrier with exudation of plasma proteins into the brain parenchyma resulting in accumulation of fluid (oedema) and eventually in formation of a cyst. There appears to be a positive relation between the grade of malignancy and the concentration of lactate in the cysts with a significant 2-fold increase in lactate concentration in malignant tumour cysts compared to the more benign tumour cysts (p < 0.001) probably on account of aerobic glycolysis with production of lactate by the tumour. The measured pH values in the cysts were above normal, resulting in a discrepancy of the high levels of lactate in the cyst with the alkaline environment and this suggests efflux of H(+)-ions by a Na/H exchange mechanism to compensate for the change of pH. PMID:9522902

  19. Understanding interactions of functionalized nanoparticles with proteins: a case study on lactate dehydrogenase.

    PubMed

    Stueker, Oliver; Ortega, Van A; Goss, Greg G; Stepanova, Maria

    2014-05-28

    Nanomaterials in biological solutions are known to interact with proteins and have been documented to affect protein function, such as enzyme activity. Understanding the interactions of nanoparticles with biological components at the molecular level will allow for rational designs of nanomaterials for use in medical technologies. Here we present the first detailed molecular mechanics model of functionalized gold nanoparticle (NP) interacting with an enzyme (L-lactate dehydrogenase (LDH) enzyme). Molecular dynamics (MD) simulations of the response of LDH to the NP binding demonstrate that although atomic motions (dynamics) of the main chain exhibit only a minor response to the binding, the dynamics of side chains are significantly constrained in all four active sites that predict alteration in kinetic properties of the enzyme. It is also demonstrated that the 5 nm gold NPs cause a decrease in the maximal velocity of the enzyme reaction (V(max)) and a trend towards a reduced affinity (increased K(m)) for the β-NAD binding site, while pyruvate enzyme kinetics (K(m) and V(max)) are not significantly altered in the presence of the gold NPs. These results demonstrate that modeling of NP:protein interactions can be used to understand alterations in protein function. PMID:24591162

  20. Identification and functional characterization of a novel monotreme- specific antibacterial protein expressed during lactation.

    PubMed

    Bisana, Swathi; Kumar, Satish; Rismiller, Peggy; Nicol, Stewart C; Lefèvre, Christophe; Nicholas, Kevin R; Sharp, Julie A

    2013-01-01

    Monotremes are the only oviparous mammals and exhibit a fascinating combination of reptilian and mammalian characters. They represent a component of synapsidal reproduction by laying shelled eggs which are incubated outside the mother's body. This is accompanied by a prototherian lactation process, marking them as representatives of early mammals. The only extant monotremes are the platypus, and the short- and long- beaked echidnas, and their distributions are limited to Australia and New Guinea. Apart for a short weaning period, milk is the sole source of nutrition and protection for the hatchlings which are altricial and immunologically naive. The duration of lactation in these mammals is prolonged relative to the gestational length and period of incubation of eggs. Much of the development of monotreme young occurs in the non-sterile ex-utero environment. Therefore the role of milk in the growth, development and disease protection of the young is of significant interest. By sequencing the cDNA of cells harvested from monotreme milk, we have identified a novel monotreme- specific transcript, and the corresponding gene was designated as the EchAMP. The expression profile of this gene in various tissues revealed that it is highly expressed in milk cells. The peptides corresponding to the EchAMP protein have been identified in a sample of echidna milk In silico analysis indicated putative antimicrobial potential for the cognate protein of EchAMP. This was further confirmed by in vitro assays using a host of bacteria. Interestingly, EchAMP did not display any activity against a commensal gut floral species. These results support the hypothesis of enhancement of survival of the young by antimicrobial bioactives of mammary gland origin and thus emphasize the protective, non- nutritional role of milk in mammals. PMID:23326486

  1. Tumor-derived PTHrP Triggers Adipose Tissue Browning and Cancer Cachexia

    PubMed Central

    Kir, Serkan; White, James P.; Kleiner, Sandra; Kazak, Lawrence; Cohen, Paul; Baracos, Vickie E.; Spiegelman, Bruce M.

    2014-01-01

    Summary Cachexia is a wasting disorder of adipose and skeletal muscle tissues that leads to profound weight loss and frailty. About half of all cancer patients suffer from cachexia, which impairs quality of life, limits cancer therapy and decreases survival. One key characteristic of cachexia is elevated resting energy expenditure, which has been linked to increased brown fat thermogenesis1-6. How tumors induce brown fat activity is unknown. Here, using lewis lung carcinoma model of cancer cachexia, we show that tumor-derived PTHrP plays an important role in wasting by driving thermogenic gene expression in adipose tissues. Neutralization of PTHrP in tumor-bearing mice blocks adipose tissue browning and also loss of muscle mass and strength. Our results demonstrate that PTHrP mediates energy wasting in fat tissues and contributes to broader aspects of cancer cachexia. Thus, neutralization of PTHrP might hold promise for fighting cancer cachexia and improving patient survival. PMID:25043053

  2. Effect of Source of Rumen-Degraded Protein on Production and Ruminal Metabolism in Lactating Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-eight (8 with ruminal cannulas) lactating Holstein cows were assigned to a 16-wk, 4 x 4 Latin squares study to examine the effect on production and ruminal metabolism of feeding differing proportions of rumen-degraded protein (RDP) from soybean meal and urea. Diets contained dry matter [(DM) ...

  3. EFFECT OF DIETARY CRUDE PROTEIN, RUMEN-UNDEGRADED PROTEIN AND RUMEN-PROTECTED METHIONINE ON MILK PRODUCTION OF LACTATING DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When crude protein (CP) is fed above that needed to meet requirements for metabolizable AA, excess urinary N contributes to environmental pollution. Rumen-undegraded protein (RUP) or rumen-protected Met (RPMet) may permit reduction of dietary CP without loss of production. A lactation trial was con...

  4. Regulation of lipid droplet-associated proteins following growth hormone administration and feed restriction in lactating Holstein cows.

    PubMed

    Faylon, M P; Koltes, D E; Spurlock, D M

    2014-05-01

    Lipid metabolism plays a crucial role in the adaptation of dairy cows to periods of energy insufficiency. The objective of the current study was to determine if lipolytic proteins are consistently regulated when energy mobilization is stimulated by different factors. We evaluated 2 models of altered energy balance in mid-lactation Holstein cows, including feed restriction (FR) and administration of bovine growth hormone (GH), by quantifying the abundance and (or) phosphorylation of hormone-sensitive lipase (HSL), perilipin (PLIN), and adipose triglyceride lipase (ATGL). For GH administration, adipose tissue and blood samples were collected 4d before and 3 and 7d after administration of GH (n=20 cows). Similarly, adipose and blood samples were obtained 6d before and 1 and 4d after initiation of FR (n=18 cows). Estimated net energy balance decreased and nonesterified fatty acid concentration increased in both experimental models. Decreased ATGL and PLIN protein abundance was observed with GH administration and FR. Additionally, the abundance of phosphorylated HSLSer565 decreased in both models. Decreased abundance of phosphorylated PLIN was observed with GH administration, but not FR. Decreased ATGL protein abundance appears to be a consistent response to energy insufficiency in lactating cows, as this response was also described with negative energy balance at the onset of lactation. In contrast, the abundance of PLIN protein and phosphorylation of HSL using antibodies targeting serine residue 565 of HSL (HSLSer565) were altered in the current research, but not at the onset of lactation. Our findings demonstrate that lipolysis is altered through the regulation of multiple proteins, and that this regulation differs according to physiological state in lactating cows. PMID:24630665

  5. Parathyroid hormone-related protein and its receptors: nuclear functions and roles in the renal and cardiovascular systems, the placental trophoblasts and the pancreatic islets

    PubMed Central

    Clemens, Thomas L; Cormier, Sarah; Eichinger, Anne; Endlich, Karlhans; Fiaschi-Taesch, Nathalie; Fischer, Evelyne; Friedman, Peter A; Karaplis, Andrew C; Massfelder, Thierry; Rossert, Jérôme; Schlüter, Klaus-Dieter; Silve, Caroline; Stewart, Andrew F; Takane, Karen; Helwig, Jean-Jacques

    2001-01-01

    The cloning of the so-called ‘parathyroid hormone-related protein' (PTHrP) in 1987 was the result of a long quest for the factor which, by mimicking the actions of PTH in bone and kidney, is responsible for the hypercalcemic paraneoplastic syndrome, humoral calcemia of malignancy. PTHrP is distinct from PTH in a number of ways. First, PTHrP is the product of a separate gene. Second, with the exception of a short N-terminal region, the structure of PTHrP is not closely related to that of PTH. Third, in contrast to PTH, PTHrP is a paracrine factor expressed throughout the body. Finally, most of the functions of PTHrP have nothing in common with those of PTH. PTHrP is a poly-hormone which comprises a family of distinct peptide hormones arising from post-translational endoproteolytic cleavage of the initial PTHrP translation products. Mature N-terminal, mid-region and C-terminal secretory forms of PTHrP are thus generated, each of them having their own physiologic functions and probably their own receptors. The type 1 PTHrP receptor, binding both PTH(1-34) and PTHrP(1-36), is the only cloned receptor so far. PTHrP is a PTH-like calciotropic hormone, a myorelaxant, a growth factor and a developmental regulatory molecule. The present review reports recent aspects of PTHrP pharmacology and physiology, including: (a) the identification of new peptides and receptors of the PTH/PTHrP system; (b) the recently discovered nuclear functions of PTHrP and the role of PTHrP as an intracrine regulator of cell growth and cell death; (c) the physiological and developmental actions of PTHrP in the cardiovascular and the renal glomerulo-vascular systems; (d) the role of PTHrP as a regulator of pancreatic beta cell growth and functions, and, (e) the interactions of PTHrP and calcium-sensing receptors for the control of the growth of placental trophoblasts. These new advances have contributed to a better understanding of the pathophysiological role of PTHrP, and will help to identify

  6. Alternative splicing of parathyroid hormone-related protein mRNA: expression and stability

    PubMed Central

    Sellers, R S; Luchin, A I; Richard, V; Brena, R M; Lima, D; Rosol, T J

    2011-01-01

    Parathyroid hormone-related protein (PTHrP) is a multifunctional protein that is often dysregulated in cancer. The human PTHrP gene is alternatively spliced into three isoforms, each with a unique 3′-untranslated region (3′-UTR), encoding 139, 173 and 141 amino acid proteins. The regulation of PTHrP mRNA isoform expression has not been completely elucidated, but it may be affected by transforming growth factor-β1 (TGF-β1). In this study, we examined differences in the PTHrP mRNA isoform expression in two squamous carcinoma cell lines (SCC2/88 and HARA), an immortalized keratinocyte cell line (HaCaT), and spontaneous human lung cancer with adjacent normal tissue. In addition, the effect of TGF-β1 on PTHrP mRNA isoform expression and stability was examined. Cell-type specific expression of PTHrP mRNA isoforms occurred between the various cell lines, normal human lung, and immortalized human keratinocytes (HaCaT). PTHrP isoform expression pattern was significantly altered between normal lung tissue and the adjacent lung cancer. In vitro studies revealed that TGF-β1 differentially altered the mRNA steady-state levels and mRNA stability of the PTHrP isoforms. Protein–RNA binding studies identified different proteins binding to the 3′-UTR of the PTHrP isoforms (139) and (141), which may be important in the differential mRNA stability and response to cytokines between the PTHrP isoforms. The data demonstrate that there is cell-type specific expression of PTHrP mRNA isoforms, and disruption of the normal regulation during cancer progression may in part be associated with TGF-β1-induced changes in PTHrP mRNA isoform expression and stability. PMID:15291755

  7. Copper transport during lactation in transgenic mice expressing the human ATP7A protein

    PubMed Central

    Llanos, Roxana M.; Michalczyk, Agnes A.; Freestone, David J.; Currie, Scott; Linder, Maria C.; Ackland, M. Leigh; Mercer, Julian F.B.

    2008-01-01

    Both copper transporting ATPases, ATP7A and ATP7B, are expressed in mammary epithelial cells but their role in copper delivery to milk has not been clarified. We investigated the role of ATP7A in delivery of copper to milk using transgenic mice that over-express human ATP7A. In mammary gland of transgenic mice, human ATP7A protein was 10- to 20-fold higher than in control mice, and was localized to the basolateral membrane of mammary epithelial cells in lactating mice. The copper concentration in the mammary gland of transgenic dams and stomach contents of transgenic pups was significantly reduced compared to non-transgenic mice. The mRNA levels of endogenous Atp7a, Atp7b, and Ctr1 copper transporters in the mammary gland were not altered by the expression of the ATP7A transgene, and the protein levels of Atp7b and ceruloplasmin were similar in transgenic and non-transgenic mice. These data suggest that ATP7A plays a role in removing excess copper from the mammary epithelial cells rather than supplying copper to milk. PMID:18515074

  8. Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows.

    PubMed

    Colmenero, J J Olmos; Broderick, G A

    2006-05-01

    Forty lactating Holstein cows, including 10 with ruminal cannulas, were blocked by days in milk into 8 groups and then randomly assigned to 1 of 8 incomplete 5 x 5 Latin squares to assess the effects of 5 levels of dietary crude protein (CP) on milk production and N use. Diets contained 25% alfalfa silage, 25% corn silage, and 50% concentrate, on a dry matter (DM) basis. Rolled high-moisture shelled corn was replaced with solvent-extracted soybean meal to increase CP from 13.5 to 15.0, 16.5, 17.9, and 19.4% of DM. Each of the 4 experimental periods lasted 28 d, with 14 d for adaptation and 14 d for data collection. Spot sampling of ruminal digesta, blood, urine, and feces was conducted on d 21 of each period. Intake of DM was not affected by diet but milk fat content as well as ruminal acetate, NH3, and branched-chain volatile fatty acids, urinary allantoin, and blood and milk urea all increased linearly with increasing CP. Milk and protein yield showed trends for quadratic responses to dietary CP and were, respectively, 38.3 and 1.18 kg/d at 16.5% CP. As a proportion of N intake, urinary N excretion increased from 23.8 to 36.2%, whereas N secreted in milk decreased from 36.5 to 25.4%, as dietary protein increased from 13.5 to 19.4%. Under the conditions of this study, yield of milk and protein were not increased by feeding more than 16.5% CP. The linear increase in urinary N excretion resulted from a sharp decline in N efficiency as dietary CP content increased. PMID:16606741

  9. Determination of protein and amino acid requirements of lactating sows using a population-based factorial approach.

    PubMed

    Strathe, A V; Strathe, A B; Theil, P K; Hansen, C F; Kebreab, E

    2015-08-01

    Determination of appropriate nutritional requirements is essential to optimize the productivity and longevity of lactating sows. The current recommendations for requirements do not consider the large variation between animals. Therefore, the aim of this study was to determine the amino acid recommendations for lactating sows using a stochastic modeling approach that integrates population variation and uncertainty of key parameters into establishing nutritional recommendations for lactating sows. The requirement for individual sows was calculated using a factorial approach by adding the requirement for maintenance and milk. The energy balance of the sows was either negative or zero depending on feed intake being a limiting factor. Some parameters in the model were sow-specific and others were population-specific, depending on state of knowledge. Each simulation was for 1000 sows repeated 100 times using Monte Carlo simulation techniques. BW, back fat thickness of the sow, litter size (LS), average litter gain (LG), dietary energy density and feed intake were inputs to the model. The model was tested using results from the literature, and the values were all within ±1 s.d. of the estimated requirements. Simulations were made for a group of low- (LS=10 (s.d.=1), LG=2 kg/day (s.d.=0.6)), medium- (LS=12 (s.d.=1), LG=2.5 kg/day (s.d.=0.6)) and high-producing (LS=14 (s.d.=1), LG=3.5 kg/day (s.d.=0.6)) sows, where the average requirement was the result. In another simulation, the requirements were estimated for each week of lactation. The results were given as the median and s.d. The average daily standardized ileal digestible (SID) protein and lysine requirements for low-, medium- and high-producing sows were 623 (CV=2.5%) and 45.1 (CV=4.8%); 765 (CV=4.9%) and 54.7 (CV=7.0%); and 996 (CV=8.5%) and 70.8 g/day (CV=9.6%), respectively. The SID protein and lysine requirements were lowest at week 1, intermediate at week 2 and 4 and the highest at week 3 of lactation. The

  10. [Ruminal digestion and intestinal absorption of lupine proteins extruded in the lactating cow].

    PubMed

    Benchaar, C; Bayourthe, C; Moncoulon, R; Vernay, M

    1991-01-01

    Four lactating cows fitted with permanent ruminal, duodenal and ileal cannulae were used to study the effect of extrusion of whole lupin seeds at 195 degrees C (Lupinus albus cv Lublanc) on organic matter (OM) and nitrogen (N) degradation in the rumen and their flow to and absorption from the small intestine. Raw whole lupin seeds (RWLS) and extruded whole lupin seeds (EWLS) were fed in diets containing 15.5% crude protein and composed of 22.6% whole lupin seeds, 56.5% corn silage, 10.2% corn grain and 10.7% Italian ray-grass on a DM basis, supplemented with vitamins and minerals. Chromium ethylenediaminotetraacetic (Cr-EDTA) and ytterbium chloride (YbCl3) were used as liquid and particulate markers respectively, while purines and 15N ammonium sulfate were utilized as bacterial markers. Cows fed EWLS had a similar ruminal ammonia N and volatile fatty acid concentrations and efficiency of bacterial protein synthesis compared to those fed the RWLS diet. Total tract OM and N digestion were not affected by inclusion of EWLS instead of RWLS; the corresponding mean values were 70 and 71%. Apparent degradation of OM and N in the rumen were 44 and 64% for diets containing RWLS, and 40 and 39% for EWLS diets. Feeding diets including EWLS both increased non ammonia N and dietary N flow to the duodenum compared with diets containing RWLS (472 vs 357 g/d) and (263 vs 153 g/d) respectively. Absorption from the small intestine (g/d and % entering) of dietary N was higher for EWLS diets (146 vs 62 g/d; 34 vs 15%). The PDIA, PDIE and PDIN contents (g/kg of DM) of RWLS were 18, 94 and 245 respectively; the corresponding values after extrusion were 145, 220 and 220. PMID:1777057

  11. Parathyroid hormone-related protein blood test

    MedlinePlus

    ... gov/ency/article/003691.htm Parathyroid hormone-related protein blood test To use the sharing features on ... page, please enable JavaScript. The parathyroid hormone-related protein (PTH-RP) test measures the level of a ...

  12. Serotonin Regulates Calcium Homeostasis in Lactation by Epigenetic Activation of Hedgehog Signaling

    PubMed Central

    Laporta, Jimena; Keil, Kimberly P.; Weaver, Samantha R.; Cronick, Callyssa M.; Prichard, Austin P.; Crenshaw, Thomas D.; Heyne, Galen W.; Vezina, Chad M.; Lipinski, Robert J.

    2014-01-01

    Calcium homeostasis during lactation is critical for maternal and neonatal health. We previously showed that nonneuronal/peripheral serotonin [5-hydroxytryptamine (5-HT)] causes the lactating mammary gland to synthesize and secrete PTHrP in an acute fashion. Here, using a mouse model, we found that genetic inactivation of tryptophan hydroxylase 1 (Tph1), which catalyzes the rate-limiting step in peripheral 5-HT synthesis, reduced circulating and mammary PTHrP expression, osteoclast activity, and maternal circulating calcium concentrations during the transition from pregnancy to lactation. Tph1 inactivation also reduced sonic hedgehog signaling in the mammary gland during lactation. Each of these deficiencies was rescued by daily injections of 5-hydroxy-L-tryptophan (an immediate precursor of 5-HT) to Tph1-deficient dams. We used immortalized mouse embryonic fibroblasts to demonstrate that 5-HT induces PTHrP through a sonic hedgehog-dependent signal transduction mechanism. We also found that 5-HT altered DNA methylation of the Shh gene locus, leading to transcriptional initiation at an alternate start site and formation of a variant transcript in mouse embryonic fibroblasts in vitro and in mammary tissue in vivo. These results support a new paradigm of 5-HT-mediated Shh regulation involving DNA methylation remodeling and promoter switching. In addition to having immediate implications for lactation biology, identification and characterization of a novel functional regulatory relationship between nonneuronal 5-HT, hedgehog signaling, and PTHrP offers new avenues for the study of these important factors in development and disease. PMID:25192038

  13. Comparative expression profiling of insulin-like growth factor binding protein-5 in milk of Bos indicus and Bubalus bubalis during lactation.

    PubMed

    Mohapatra, S K; Singh, S; Kumar, S; Dang, A K; Datta, T K; Das, S K; Mohanty, T K; Kaushik, J K; Mohanty, A K

    2015-04-01

    Insulin-like growth factor binding protein-5 (IGFBP-5) is a key molecule in mammary gland development, which facilitates the removal of mammary epithelial cells (MECs) by apoptosis that takes place during remodeling of the mammary gland during involution. IGFBP-5 binds with IGFs for their bioavailability. IGFBP-5 has been reported to perform pleiotropic roles such as cellular apoptosis, proliferation and differentiation. To understand the role of IGFBP-5 during lactation and clinical mastitis, expression profiling of IGFBP-5 at the protein level was performed in both indigenous cows (Bos indicus) and buffaloes (Bubalus bubalis) belonging to two different breeds - Sahiwal cows and Murrah buffaloes. Reverse-transcriptase PCR (RT-PCR) of IGFBP-5 mRNA confirmed its expression in milk somatic cells and MECs of Sahiwal cows. ELISA was performed for quantitative measurement of IGFBP-5 concentrations in milk during different days (0, 50, 100, 150, 200, 250 and 300) of lactation, during the involution period and in animals exhibiting short lactation and clinical mastitis. The highest concentration of IGFBP-5 in milk was observed during the involution period followed by colostrum, late and early lactation, respectively, in both cattle and buffaloes. No significant difference in the concentration of IGFBP-5 was observed during the first 150 days of lactation between cows and buffaloes. However, higher concentration of IGFBP-5 was observed in cows during late lactation (200 to 300 days) in comparison with buffaloes. To validate the ELISA data, quantitative real-time PCR was performed in MECs of Sahiwal cows. The relative mRNA abundance of IGFBP-5 was found to be significantly (P<0.05) higher on day 15 than between 50 and 150 days of lactation in case of Sahiwal cows. Highest mRNA expression of IGFBP-5 was observed around 300 days of lactation followed by 200 and 250 days (P<0.05), respectively. Murrah buffaloes showed low levels of IGFBP-5 protein in milk as compared with

  14. Lactational performance of dairy cows fed raw soybeans, with or without animal by-product proteins, or roasted soybeans.

    PubMed

    Grummer, R R; Luck, M L; Barmore, J A

    1994-05-01

    Twelve multiparous Holstein cows averaged 10 wk postpartum and were used in a replicated 3 x 3 Latin square design to compare two feeding strategies for increasing the ratio of dietary undegradable to degradable protein. Treatments were raw soybeans, with or without meat and bone meal plus blood meal, and roasted soybeans as the primary protein supplements. Meat and bone meal and blood meal were fed at 4.0 and .9% of dietary DM, respectively. Basal diets were 30% alfalfa silage, 18% corn silage, and 52% corn-based concentrate mix. Diets were formulated to be isonitrogenous and isocaloric. Estimated undegradable protein contents, as a percentage of total CP, were 32.2, 36.2, and 34.3 for diets containing raw soybeans, raw soybeans plus animal by-product proteins, and roasted soybeans, respectively. The undegradable protein estimates were calculated from NRC values for basal feeds and from results of in vitro analysis of test protein supplements. Yields of milk and 3.5% FCM of cows receiving raw soybeans plus animal by-product proteins (45.5 and 43.4 kg/d) and roasted soybeans (44.7 and 42.7 kg/d) were greater than those of cows receiving raw soybeans alone (43.2 and 41.3 kg/d). Increasing the ratio of undegradable to degradable dietary protein also increased yields of milk protein and fat. No differences occurred in lactation performance among cows fed the two diets containing higher undegradable protein. The DMI was not influenced by treatment. Increasing the ratio of undegradable to degradable dietary protein by feeding animal by-product proteins or heated soybeans enhanced lactation performance. PMID:8046075

  15. Effect of dietary protein content on estrous behavior of dairy cows during early and mid lactation.

    PubMed

    Law, R A; Young, F J; Patterson, D C; Kilpatrick, D J; Wylie, A R G; Mayne, C S

    2009-03-01

    One of the main contributing factors to the decline in fertility in contemporary dairy farming is the inability to detect cows in estrus. In the current study, 90 Holstein dairy cows [45 primiparous and 45 multiparous (mean parity of 3.1)] were allocated to 1 of 3 treatments at calving; 173, 144, or 114 g of crude protein/kg of dry matter. Estrous behavior was recorded for one 30-min period every 12 h from calving until all animals reached 140 d postpartum. Behavioral activities were recorded according to a scoring system developed by Van Eerdenburg et al. (1996), with 9 key estrous behavioral activities each allocated a given number of points. If the total score allocated was greater than or equal to 50 points during a single or consecutive observational periods, then the animal was deemed to be in estrus. A total of 238 estrous cycles scored 50 points or above on the Van Eerdenburg et al. (1996) scale in this experiment, with 51.7% of these cycles being characterized as standing immobile on mounting. There were no direct effects of dietary protein content on estrous behavior; however, 3 significant stage of lactation x protein treatment interactions occurred for the behavioral activities (mucous discharge, chin resting, and mounting the head side of another cow), but no consistent trends were apparent from the predicted means. There was a significant influence of parity on the frequency of mounting the head side of another cow and total number of behavior activities displayed per estrous cycle. In both cases multiparous animals displayed fewer behavioral activities than primiparous animals. An increase in the size of the sexually active group (animals in estrus at the same time, up to 5) significantly increased the expression of mounting or attempting to mount another cow, the number of cycles in which standing immobile on being mounted was observed, the total estrous score and the proportion of cyclic animals that were diagnosed as being in estrus. The most

  16. Genetic parameters for lactation traits of milking ewes: protein content and composition, fat, somatic cells and individual laboratory cheese yield

    PubMed Central

    Othmane, Med Houcine; Carriedo, Juan Antonio; San Primitivo, Fermin; De la Fuente, Luis Fernando

    2002-01-01

    The effects of some environmental variation factors and the genetic parameters for total milk traits (fat content, protein content, casein content, serum protein content, lactation mean of individual laboratory cheese yield (LILCY), lactation mean of somatic cell count (LSCC), and milk yield) were estimated from the records of 1 111 Churra ewes. Genetic parameters were estimated by multivariate REML. Heritability for fat content was low (0.10) as is usually found in the Churra breed. Heritabilities for protein content, casein content, serum protein content, LILCY, milk yield and somatic cell count were 0.31, 0.30, 0.22, 0.09, 0.26 and 0.11, respectively. The highest heritability estimates were for protein and casein contents. Casein content is not advisable as an alternative to protein content as a selection criterion for cheese yield improvement; it does not have any compelling advantages and its measurement is costly. Our results for LSCC indicated that efforts should focus on improving the level of management rather than selecting for somatic cells, in the actual conditions of the Churra breed. PMID:12427387

  17. Serum parathyroid hormone-related protein concentration in a dog with a thymoma and persistent hypercalcemia.

    PubMed Central

    Foley, P; Shaw, D; Runyon, C; McConkey, S; Ikede, B

    2000-01-01

    A thymoma was tentatively diagnosed by radiographic and cytologic examination in a dog with hypercalcemia and elevated serum parathyroid hormone-related protein (PTHrP) concentration. Following surgical excision, the diagnosis of thymoma was confirmed via histopathologic examination, the hypercalcemia resolved, and the PTHrP concentration decreased to below detectable limits. Images Figure 1. Figure 2. PMID:11126493

  18. Protein level for alfalfa and corn silage-based diets: I. Lactational response and milk urea nitrogen.

    PubMed

    Wattiaux, M A; Karg, K L

    2004-10-01

    This study was designed to evaluate lactational responses of cows fed corn silage (CS) or alfalfa silage (AS) as primary forage source when the diet was balanced for recommended (RP) or excessive (HP) amounts of rumen degradable protein (RDP) and undegradable protein (RUP) according to the recommendations of the National Research Council (NRC). A second objective was to evaluate different sources of variations in milk urea N (MUN). The total mixed rations included 55% forage on a dry matter (DM) basis as either 14% CS and 41% AS or 14% AS and 41% CS. Diets were offered to 48 multiparous Holstein cows (body weight = 652 kg) that were assigned randomly to treatments arranged as a 2 x 2 factorial in 12 complete blocks based on calving date. Data collected during wk 4 to 12 of lactation were adjusted to those obtained from a pretreatment diet fed during wk 1 to 3. Crude protein (CP) averaged 16.5, 18.0, 16.2, and 17.1% of DM in the AS-RP; AS-HP; CS-RP; and CS-HP diets, respectively. Overall DM intake (DMI) was 1.5 kg/d lower than predicted by NRC (24.6 vs. 26.1 kg/d), but 3.5% fat-corrected milk (FCM) was higher than expected (46.1 vs. 45.0 kg/d). The responses to a reduction in dietary protein were independent of primary forage source, except for milk true protein (TP) percentage. Primary forage source did not influence DMI, 3.5% FCM, TP yield, or MUN. However, compared with the AS-based diets, cows fed CS-based diets produced more milk (49.0 vs. 46.4 kg/d), less fat (3.07% vs. 3.54% and 1500 vs. 1651 g/d), and tended to gain more body weight. There were no benefits to feeding diets above NRC protein recommendations, regardless of forage source. Reducing CP from 17.5 to 16.4% of diet DM did not alter milk yield (47.7 kg/d) or milk TP yield (1293 g/d), but lowered N intake by 65 g/d (700 vs. 635 g/d) and lowered MUN by 1 unit (12.7 vs. 11.7 mg/dL). A positive correlation between MUN and production efficiency (3.5% FCM/DMI) on wk 3 of lactation suggested that body

  19. Changes over lactation in breast milk serum proteins involved in the maturation of immune and digestive system of the infant.

    PubMed

    Zhang, Lina; de Waard, Marita; Verheijen, Hester; Boeren, Sjef; Hageman, Jos A; van Hooijdonk, Toon; Vervoort, Jacques; van Goudoever, Johannes B; Hettinga, Kasper

    2016-06-01

    Here we provide data from shot-gun proteomics, using filtered-aided sample preparation (FASP), dimethyl labeling and LC-MS/MS, to quantify the changes in the repertoire of human milk proteins over lactation. Milk serum proteins were analyzed at week 1, 2, 3 4, 8, 16, and 24 in milk from four individual mothers. A total of 247 proteins were identified, of which 200 proteins were quantified. The data supplied in this article supports the accompanying publication (Zhang et al., 2006) [1]. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (Vizcaíno et al., 2016) [2] via the PRIDE partner repository with the dataset identifier PXD003465. PMID:26977438

  20. Changes over lactation in breast milk serum proteins involved in the maturation of immune and digestive system of the infant

    PubMed Central

    Zhang, Lina; de Waard, Marita; Verheijen, Hester; Boeren, Sjef; Hageman, Jos A.; van Hooijdonk, Toon; Vervoort, Jacques; van Goudoever, Johannes B.; Hettinga, Kasper

    2016-01-01

    Here we provide data from shot-gun proteomics, using filtered-aided sample preparation (FASP), dimethyl labeling and LC–MS/MS, to quantify the changes in the repertoire of human milk proteins over lactation. Milk serum proteins were analyzed at week 1, 2, 3 4, 8, 16, and 24 in milk from four individual mothers. A total of 247 proteins were identified, of which 200 proteins were quantified. The data supplied in this article supports the accompanying publication (Zhang et al., 2006) [1]. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (Vizcaíno et al., 2016) [2] via the PRIDE partner repository with the dataset identifier PXD003465. PMID:26977438

  1. The parathyroid hormone-related protein is secreted during the osteogenic differentiation of human dental follicle cells and inhibits the alkaline phosphatase activity and the expression of DLX3.

    PubMed

    Klingelhöffer, C; Reck, A; Ettl, T; Morsczeck, C

    2016-08-01

    The dental follicle is involved in tooth eruption and it expresses a great amount of the parathyroid hormone-related protein (PTHrP). PTHrP as an extracellular protein is required for a multitude of different regulations of enchondral bone development and differentiation of bone precursor cells and of the development of craniofacial tissues. The dental follicle contains also precursor cells (DFCs) of the periodontium. Isolated DFCs differentiate into periodontal ligament cells, alveolar osteoblast and cementoblasts. However, the role of PTHrP during the human periodontal development remains elusive. Our study evaluated the influence of PTHrP on the osteogenic differentiation of DFCs under in vitro conditions for the first time. The PTHrP protein was highly secreted after 4days of the induction of the osteogenic differentiation of DFCs with dexamethasone (2160.5pg/ml±345.7SD. in osteogenic differentiation medium vs. 315.7pg/ml±156.2SD. in standard cell culture medium; Student's t Test: p<0.05 (n=3)). We showed that the supplementation of the osteogenic differentiation medium with PTHrP inhibited the alkaline phosphatase activity and the expression of the transcription factor DLX3, but the depletion of PTHrP did not support the differentiation of DFCs. Previous studies have shown that Indian Hedgehog (IHH) induces PTHrP and that PTHrP, in turn, inhibits IHH via a negative feedback loop. We showed that SUFU (Suppressor Of Fused Homolog) was not regulated during the osteogenic differentiation in DFCs. So, neither the hedgehog signaling pathway induced PTHrP nor PTHrP suppressed the hedgehog signaling pathway during the osteogenic differentiation in DFCs. In conclusion, our results suggest that PTHrP regulates independently of the hedgehog signaling pathway the osteogenic differentiated in DFCs. PMID:27368119

  2. Decreased liver triglyceride content in adult rats exposed to protein restriction during gestation and lactation: role of hepatic triglyceride utilization

    PubMed Central

    Qasem, Rani J.; Li, Jing; Tang, Hee Man; Browne, Veron; Mendez, Claudia; Yablonski, Elizabeth; Pontiggia, Laura; D’mello, Anil P.

    2015-01-01

    We have previously demonstrated that protein restriction throughout gestation and lactation reduced liver triglyceride content in adult rat offspring. The mechanism(s) mediating the decrease in liver triglyceride content are not understood. The objective of the current study was to use a new group of pregnant animals and their offspring and determine the contribution of increased triglyceride utilization via the hepatic fatty acid oxidation and triglyceride secretory pathways to the reduction in liver triglyceride content. Pregnant Sprague-Dawley rats received either a control or a low protein diet throughout pregnancy and lactation. Pups were weaned onto laboratory chow on day 28 and sacrificed on day 65. Liver triglyceride content was reduced in male, but not female, low protein offspring both in the fed and fasted states. The reduction was accompanied by a trend towards higher liver carnitine palmitoyltransferase-1a activity suggesting increased fatty acid transport into the mitochondrial matrix. However, medium chain acyl CoA dehydrogenase activity within the mitochondrial matrix, expression of nuclear peroxisome proliferator activated receptor-α, and plasma levels of β-hydroxybutyrate were similar between low protein and control offspring indicating a lack of change in fatty acid oxidation. Hepatic triglyceride secretion, assessed by blocking peripheral triglyceride utilization and measuring serum triglyceride accumulation rate, and the activity of microsomal transfer protein were similar between low protein and control offspring. Since enhanced triglyceride utilization is not a significant contributor, the decrease in liver triglyceride content in male low protein offspring is likely due to alterations in liver fatty acid transport or triglyceride biosynthesis. PMID:25641378

  3. Decreased liver triglyceride content in adult rats exposed to protein restriction during gestation and lactation: role of hepatic triglyceride utilization.

    PubMed

    Qasem, Rani J; Li, Jing; Tang, Hee Man; Browne, Veron; Mendez-Garcia, Claudia; Yablonski, Elizabeth; Pontiggia, Laura; D'Mello, Anil P

    2015-04-01

    We have previously demonstrated that protein restriction throughout gestation and lactation reduces liver triglyceride content in adult rat offspring. However, the mechanisms mediating the decrease in liver triglyceride content are not understood. The aim of the current study was to use a new group of pregnant animals and their offspring and determine the contribution of increased triglyceride utilization via the hepatic fatty-acid oxidation and triglyceride secretory pathways to the reduction in liver triglyceride content. Pregnant Sprague-Dawley rats received either a control or a low protein diet throughout pregnancy and lactation. Pups were weaned onto laboratory chow on day 28 and killed on day 65. Liver triglyceride content was reduced in male, but not female, low-protein offspring, both in the fed and fasted states. The reduction was accompanied by a trend towards higher liver carnitine palmitoyltransferase-1a activity, suggesting increased fatty-acid transport into the mitochondrial matrix. However, medium-chain acyl coenzyme A dehydrogenase activity within the mitochondrial matrix, expression of nuclear peroxisome proliferator activated receptor-α, and plasma levels of β-hydroxybutyrate were similar between low protein and control offspring, indicating a lack of change in fatty-acid oxidation. Hepatic triglyceride secretion, assessed by blocking peripheral triglyceride utilization and measuring serum triglyceride accumulation rate, and the activity of microsomal transfer protein, were similar between low protein and control offspring. Because enhanced triglyceride utilization is not a significant contributor, the decrease in liver triglyceride content in male low-protein offspring is likely due to alterations in liver fatty-acid transport or triglyceride biosynthesis. PMID:25641378

  4. Protein Conformational Landscapes and Catalysis. Influence of Active Site Conformations in the Reaction Catalyzed by L-Lactate Dehydrogenase

    PubMed Central

    Świderek, Katarzyna; Tuñón, Iñaki; Martí, Sergio; Moliner, Vicent

    2015-01-01

    In the last decade L-Lactate Dehydrogenase (LDH) has become an extremely useful marker in both clinical diagnosis and in monitoring the course of many human diseases. It has been assumed from the 80s that the full catalytic process of LDH starts with the binding of the cofactor and the substrate followed by the enclosure of the active site by a mobile loop of the protein before the reaction to take place. In this paper we show that the chemical step of the LDH catalyzed reaction can proceed within the open loop conformation, and the different reactivity of the different protein conformations would be in agreement with the broad range of rate constants measured in single molecule spectrometry studies. Starting from a recently solved X-ray diffraction structure that presented an open loop conformation in two of the four chains of the tetramer, QM/MM free energy surfaces have been obtained at different levels of theory. Depending on the level of theory used to describe the electronic structure, the free energy barrier for the transformation of pyruvate into lactate with the open conformation of the protein varies between 12.9 and 16.3 kcal/mol, after quantizing the vibrations and adding the contributions of recrossing and tunneling effects. These values are very close to the experimentally deduced one (14.2 kcal·mol−1) and ~2 kcal·mol−1 smaller than the ones obtained with the closed loop conformer. Calculation of primary KIEs and IR spectra in both protein conformations are also consistent with our hypothesis and in agreement with experimental data. Our calculations suggest that the closure of the active site is mainly required for the inverse process; the oxidation of lactate to pyruvate. According to this hypothesis H4 type LDH enzyme molecules, where it has been propose that lactate is transformed into pyruvate, should have a better ability to close the mobile loop than the M4 type LDH molecules. PMID:25705562

  5. mTORC1 regulates PTHrP to coordinate chondrocyte growth, proliferation and differentiation.

    PubMed

    Yan, Bo; Zhang, Zhongmin; Jin, Dadi; Cai, Chen; Jia, Chunhong; Liu, Wen; Wang, Ting; Li, Shengfa; Zhang, Haiyan; Huang, Bin; Lai, Pinglin; Wang, Hua; Liu, Anling; Zeng, Chun; Cai, Daozhang; Jiang, Yu; Bai, Xiaochun

    2016-01-01

    Precise coordination of cell growth, proliferation and differentiation is essential for the development of multicellular organisms. Here, we report that although the mechanistic target of rapamycin complex 1 (mTORC1) activity is required for chondrocyte growth and proliferation, its inactivation is essential for chondrocyte differentiation. Hyperactivation of mTORC1 via TSC1 gene deletion in chondrocytes causes uncoupling of the normal proliferation and differentiation programme within the growth plate, resulting in uncontrolled cell proliferation, and blockage of differentiation and chondrodysplasia in mice. Rapamycin promotes chondrocyte differentiation and restores these defects in mutant mice. Mechanistically, mTORC1 downstream kinase S6K1 interacts with and phosphorylates Gli2, and releases Gli2 from SuFu binding, resulting in nuclear translocation of Gli2 and transcription of parathyroid hormone-related peptide (PTHrP), a key regulator of bone development. Our findings demonstrate that dynamically controlled mTORC1 activity is crucial to coordinate chondrocyte proliferation and differentiation partially through regulating Gli2/PTHrP during endochondral bone development. PMID:27039827

  6. mTORC1 regulates PTHrP to coordinate chondrocyte growth, proliferation and differentiation

    PubMed Central

    Yan, Bo; Zhang, Zhongmin; Jin, Dadi; Cai, Chen; Jia, Chunhong; Liu, Wen; Wang, Ting; Li, Shengfa; Zhang, Haiyan; Huang, Bin; Lai, Pinglin; Wang, Hua; Liu, Anling; Zeng, Chun; Cai, Daozhang; Jiang, Yu; Bai, Xiaochun

    2016-01-01

    Precise coordination of cell growth, proliferation and differentiation is essential for the development of multicellular organisms. Here, we report that although the mechanistic target of rapamycin complex 1 (mTORC1) activity is required for chondrocyte growth and proliferation, its inactivation is essential for chondrocyte differentiation. Hyperactivation of mTORC1 via TSC1 gene deletion in chondrocytes causes uncoupling of the normal proliferation and differentiation programme within the growth plate, resulting in uncontrolled cell proliferation, and blockage of differentiation and chondrodysplasia in mice. Rapamycin promotes chondrocyte differentiation and restores these defects in mutant mice. Mechanistically, mTORC1 downstream kinase S6K1 interacts with and phosphorylates Gli2, and releases Gli2 from SuFu binding, resulting in nuclear translocation of Gli2 and transcription of parathyroid hormone-related peptide (PTHrP), a key regulator of bone development. Our findings demonstrate that dynamically controlled mTORC1 activity is crucial to coordinate chondrocyte proliferation and differentiation partially through regulating Gli2/PTHrP during endochondral bone development. PMID:27039827

  7. The effects of aging and maternal protein restriction during lactation on thymic involution and peripheral immunosenescence in adult mice

    PubMed Central

    Heppolette, Chantal A. A.; Chen, Jian-Hua; Carr, Sarah K.; Palmer, Donald B.; Ozanne, Susan E.

    2016-01-01

    Environmental factors such as nutrition during early life can influence long-term health, a concept termed developmental programming. Initial research was focused towards the effects on metabolic health but more recent studies have demonstrated effects on parameters such as lifespan and immunity. In this study we report that maternal protein restriction during lactation in mice, that is known to prolong lifespan, slows aging of the central and peripheral immune systems. Offspring of dams fed a postnatal low-protein (PLP) diet during lactation had a significant increase in thymic cellularity and T cell numbers across their lifespan compared to controls, and a less marked age-associated decrease in thymocyte cluster of differentiation (CD) 3 expression. PLP animals also demonstrated increased relative splenic cellularity, increased naïve: memory CD4+ and CD8+ T cell ratios, increased staining and density of germinal centres, and decreased gene expression of p16 in the spleen, a robust biomarker of aging. A slower rate of splenic aging in PLP animals would be expected to result in decreased susceptibility to infection and neoplasia. In conclusion nutritionally-induced slow postnatal growth leads to delayed aging of the adaptive immune system, which may contribute towards the extended lifespan observed in these animals. PMID:26843625

  8. The effects of aging and maternal protein restriction during lactation on thymic involution and peripheral immunosenescence in adult mice.

    PubMed

    Heppolette, Chantal A A; Chen, Jian-Hua; Carr, Sarah K; Palmer, Donald B; Ozanne, Susan E

    2016-02-01

    Environmental factors such as nutrition during early life can influence long-term health, a concept termed developmental programming. Initial research was focused towards the effects on metabolic health but more recent studies have demonstrated effects on parameters such as lifespan and immunity. In this study we report that maternal protein restriction during lactation in mice, that is known to prolong lifespan, slows aging of the central and peripheral immune systems. Offspring of dams fed a postnatal low-protein (PLP) diet during lactation had a significant increase in thymic cellularity and T cell numbers across their lifespan compared to controls, and a less marked age-associated decrease in thymocyte cluster of differentiation (CD) 3 expression. PLP animals also demonstrated increased relative splenic cellularity, increased naïve: memory CD4+ and CD8+ T cell ratios, increased staining and density of germinal centres, and decreased gene expression of p16 in the spleen, a robust biomarker of aging. A slower rate of splenic aging in PLP animals would be expected to result in decreased susceptibility to infection and neoplasia. In conclusion nutritionally-induced slow postnatal growth leads to delayed aging of the adaptive immune system, which may contribute towards the extended lifespan observed in these animals. PMID:26843625

  9. Increased Leptin Response and Inhibition of Apoptosis in Thymocytes of Young Rats Offspring from Protein Deprived Dams during Lactation

    PubMed Central

    da Silva, Simone Vargas; Salama, Carolina; Renovato-Martins, Mariana; Helal-Neto, Edward; Citelli, Marta; Savino, Wilson; Barja-Fidalgo, Christina

    2013-01-01

    We investigated the consequences of mild maternal malnutrition in rat dams, in terms of thymocyte responses and the putative role of leptin. The young progeny of dams submitted to protein deprivation (PD) during lactation showed at 30 days of age lower body and thymus weights, significant alterations in CD4/CD8-defined T cell subsets without modifications in total thymocyte number as well as in proliferative response. Despite, the rats from PD group did not present alterations in leptin circulating levels, the expression of leptin receptor ObRb was enhanced in their thymocytes. This change was accompanied by an increase in leptin signaling response of thymocytes from PD rats, with an increase in JAK2 and STAT3 phosphorylation after leptin stimulation. Thymocytes from PD rats also presented a decreased rate of spontaneous apoptosis when compared to controls. Accordingly, higher expression of anti-apoptotic protein Bcl-2, and lower of pro-apoptotic protein Bax, with no change of pro-apoptotic Bad, and higher pro-caspase 3 content were detected in PD thymocytes. Moreover, thymocytes from PD group exhibited a constitutive higher nuclear content of p65 NF-kB associated to a lower IkB content in the cytoplasm. Finally, although there was no change in ob gene expression in PD thymocytes, a higher mRNA expression for the Ob gene was observed in the thymic microenvironment from PD animals. Taken together, the results show that mild maternal protein deprivation during lactation affects thymic homeostasis, enhancing leptin activity, which in turn protects thymocytes from apoptosis in the young progeny, with possible consequences upon the immune response of these animals in adult life. PMID:23675529

  10. Lactate dehydrogenase A as a highly abundant eye lens protein in platypus (Ornithorhynchus anatinus): upsilon (upsilon)-crystallin.

    PubMed

    van Rheede, Teun; Amons, Reinout; Stewart, Niall; de Jong, Wilfried W

    2003-06-01

    Vertebrate eye lenses mostly contain two abundant types of proteins, the alpha-crystallins and the beta/gamma-crystallins. In addition, certain housekeeping enzymes are highly expressed as crystallins in various taxa. We now observed an unusual approximately 41-kd protein that makes up 16% to 18% of the total protein in the platypus eye lens. Its cDNA sequence was determined, which identified the protein as muscle-type lactate dehydrogenase A (LDH-A). It is the first observation of LDH-A as a crystallin, and we designate it upsilon (upsilon)-crystallin. Interestingly, the related heart-type LDH-B occurs as an abundant lens protein, known as epsilon-crystallin, in many birds and crocodiles. Thus, two members of the ldh gene family have independently been recruited as crystallins in different higher vertebrate lineages, suggesting that they are particularly suited for this purpose in terms of gene regulatory or protein structural properties. To establish whether platypus LDH-A/upsilon-crystallin has been under different selective constraints as compared with other vertebrate LDH-A sequences, we reconstructed the vertebrate ldh-a gene phylogeny. No conspicuous rate deviations or amino acid replacements were observed. PMID:12716980

  11. Elevation of PTH and PTHrp induced by excessive fluoride in rats on a calcium-deficient diet.

    PubMed

    Xu, Hui; Liu, Qin-Yi; Zhang, Jing-Min; Zhang, He; Li, Guang-Sheng

    2010-10-01

    Study on the role of parathyroid hormone (PTH) and parathyroid hormone-related peptide (PTHrp) in the process of skeletal fluorosis, involved especially in calcium deficiency, is rare. We evaluated the level of serum PTH and mRNA expression of PTHrp in femur when rats were exposed to excessive fluoride with low-calcium diet. Wistar rats (n = 60) was divided into four groups, a control group, fluoride group, low-calcium group, and low-calcium fluoride group. The fluoride groups were treated with fluoride by drinking tap water containing 100 mg F-/L. The low-calcium diet contained 0.05% calcium. Serum was collected in the first, fourth, eighth, and 12th of phase for the detemination of PTH and Ca(2+). RNA extraction from femora was used to analyze the mRNA express of PTHrp, osteopontin (OPN), and osteocalcin (OCN) after 12 weeks of fluoride dosing. Results showed that serum PTH increased gradually with the extension of fluoride exposure, but Ca2+ decreased, both of which embodied a time-dependent relationship. Cotreatment of excessive fluoride with low-calcium diet largely stimulated the secretion of PTH. The low dietary calcium markedly increased mRNA expression of PTHrp in animals with fluoride treatment. Expression of OPN and OCN significantly increased in the rats treated with excessive fluoride and low-calcium diet. We demonstrated that fluoride by itself affected the body's calcium metabolism and stimulate the secretion of PTH. PTH may play an important role in anabolic effect of excessive fluoride on bone turnover of skeletal fluorosis and calcium deficiency exacerbated the action of PTH and PTHrp on the characteristic bone lesion of fluorosis. PMID:19915804

  12. Analysis of production responses to changing crude protein levels in lactating dairy cow diets when evaluated in continuous or change-over experimental designs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate by meta-analysis the effect of experimental design on the production response functions obtained when changing crude protein levels in lactating dairy cow diets. The final database of studies that met the selection criteria contained 55 publications with 2...

  13. EFFECT OF INTRAVENOUS INFUSION OF INCREASING AMOUNTS OF LIPOPOYSACCHARIDE ON PLASMA MACRO-MINERAL, VITAMIN D, AND PROTEIN CONCENTRATIONS IN LACTATING DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four multiparous lactating cows (175-220 DIM) were used in a 4x4 Latin square design to assess the effects of increasing doses (0.0, 0.5, 1.0, 1.5 ug/kg BW) of lipopolysaccharide (LPS; E. coli 0111:B4) on plasma concentrations of macro-minerals, vitamin D, and protein. Treatments were dissolved in ...

  14. Effect of dietary level of rumen-degraded protein on production and nitrogen metabolism in lactating dairy cows.

    PubMed

    Reynal, S M; Broderick, G A

    2005-11-01

    Twenty-eight (8 with ruminal cannulas) lactating Holstein cows were assigned to 4 x 4 Latin squares and fed diets with different levels of rumen-degraded protein (RDP) to study the effect of RDP on production and N metabolism. Diets contained [dry matter (DM) basis] 37% corn silage, 13% alfalfa silage, and 50% concentrate. The concentrate contained solvent and lignosulfonate-treated soybean meal and urea, and was adjusted to provide RDP at: 13.2, 12.3, 11.7, and 10.6% of DM in diets A to D, respectively. Intake of DM and yield of milk, fat-corrected milk, and fat were not affected by treatments. Dietary RDP had positive linear effects on milk true protein content and microbial non-ammonia N (NAN) flow at the omasal canal, and a quadratic effect on true protein yield, with maximal protein production at 12.3% RDP. However, dietary RDP had a positive linear effect on total N excretion, with urinary N accounting for most of the increase, and a negative linear effect on environmental N efficiency (kg of milk produced per kg of N excreted). Therefore, a compromise between profitability and environmental quality was achieved at a dietary RDP level of 11.7% of DM. Observed microbial NAN flow and RDP supply were higher and RUP flow was lower than those predicted by the NRC (2001) model. The NRC (2001) model overpredicted production responses to RUP compared with the results in this study. Replacing default NRC degradation rates for protein supplements with rates measured in vivo resulted in similar observed and predicted values, suggesting that in situ degradation rates used by the NRC are slower than apparent rates in this study. PMID:16230710

  15. Short communication: Casein hydrolysate and whey proteins as excipients for cyanocobalamin to increase intestinal absorption in the lactating dairy cow.

    PubMed

    Artegoitia, V M; de Veth, M J; Harte, F; Ouellet, D R; Girard, C L

    2015-11-01

    Bioavailability of vitamin B12 is low in humans and animals. Improving vitamin B12 absorption is important for optimal performance in dairy cows and for increasing vitamin B12 concentrations in milk for human consumption. However, when supplemented in the diet, 80% of synthetic vitamin B12, cyanocobalamin (CN-CBL), is degraded in the rumen of dairy cows and only 25% of the amount escaping destruction in the rumen disappears from the small intestine between the duodenal and ileal cannulas. In pigs, vitamin B12 from milk is more efficiently absorbed than synthetic CN-CBL. The objective of this study was to determine the efficacy of casein hydrolysate and whey proteins as excipients for CN-CBL to increase portal-drained viscera (PDV) flux of the vitamin in lactating dairy cows. Four multiparous lactating Holstein cows (237 ± 17 DIM) equipped with a rumen cannula and catheters in the portal vein and a mesenteric artery were used in a randomized Youden square design. They were fed every 2 h to maintain steady digesta flow. On experimental days, they received a postruminal bolus of (1) CN-CBL alone (0.1 g), (2) CN-CBL (0.1 g) + casein hydrolysate (10 g), or (3) CN-CBL (0.1 g) + whey proteins (10 g). Starting 30 min after the bolus, blood samples were taken simultaneously from the 2 catheters every 15 min during the first 2 h and then every 2 h until 24 h postbolus. Milk yield, DMI, and vitamin B12 portal-arterial difference and PDV flux were analyzed using the MIXED procedure of SAS. Milk yield and DMI were not affected by treatments. The portal-arterial difference of vitamin B12 during the 24-h period following the bolus of vitamin was greater when the vitamin was given in solution with casein hydrolysate (2.9 ± 4.6 pg/mL) than alone (-17.5 ± 5.2 pg/mL) or with whey protein (-13.4 ± 4.2 pg/mL). The treatment effects were similar for the PDV flux. The present results suggest that CN-CBL given with casein hydrolysate increases vitamin B12 absorption as compared with

  16. High-protein nutrition during pregnancy and lactation programs blood pressure, food efficiency, and body weight of the offspring in a sex-dependent manner.

    PubMed

    Thone-Reineke, C; Kalk, P; Dorn, M; Klaus, S; Simon, K; Pfab, T; Godes, M; Persson, P; Unger, T; Hocher, B

    2006-10-01

    Maternal low-protein diet during pregnancy is a risk factor for cardiovascular disease of the offspring in later life. The impact of high-protein diet during pregnancy on the cardiovascular phenotype of the offspring, however, is still unknown. We examined the influence of a high-protein diet during pregnancy and lactation on the renal, hemodynamic, and metabolic phenotype of the F1 generation. Female Wistar rats were either fed a normal protein diet (20% protein: NP) or an isocaloric high-protein diet (40% protein: HP) throughout pregnancy and lactation. At weaning, the offspring were fed with standard diet, and they were allocated according to sex and maternal diet to four groups: normal-protein male (NPm, n = 25), normal-protein female (NPf, n = 19), high-protein male (HPm, n = 24), high-protein female (HPf, n = 29). During the experiment (22 wk), the animals were characterized by repeated measurement of body weight, food intake, blood pressure, glucose tolerance, energy expenditure, and kidney function. At the end of the study period histomorphological analyses of the kidneys and weight measurement of reproductive fat pads were conducted. There were no differences in birth weight between the study groups. No influence of maternal diet on energy expenditure, glucose tolerance, and plasma lipid levels was detected. Blood pressure and glomerulosclerosis were elevated in male offspring only, whereas female offspring were characterized by an increased food efficiency, higher body weight, and increased fat pads. Our study demonstrates that a high-protein diet during pregnancy and lactation in rats programs blood pressure, food efficiency, and body weight of the offspring in a sex-dependent manner. PMID:16675628

  17. A comparative study of different protein immobilization methods for the construction of an efficient nano-structured lactate oxidase-SWCNT-biosensor

    PubMed Central

    Pagán, Miraida; Suazo, Dámaris; del Toro, Nicole; Griebenow, Kai

    2014-01-01

    We constructed lactate biosensors by immobilization of lactate oxidase (LOx) onto a single-walled carbon nanotube (SWCNT) electrode. The first step of the sensor construction was the immobilization of oxidized SWCNT onto a platinum electrode modified with 4-aminothiophenol (4-ATP). Two enzyme immobilization methods were used to construct the biosensors, i.e., covalent immobilization using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and physical adsorption. Atomic force microscopy (AFM) experiments confirmed the immobilization of SWCNT during the biosensor construction and X-ray photoelectron spectroscopy (XPS) experiments confirmed covalent immobilization of LOx onto the SWCNT in the first method. The biosensor based on covalent enzyme immobilization showed a sensitivity of 5.8 μA/mM, a linearity up to 0.12 mM of L-lactate, and a detection limit of 4.0 μM. The biosensor based on protein adsorption displayed a sensitivity of 9.4 μA/mM, retaining linearity up to 0.18 mM of L-lactate with a detection limit of 3.0 μM. The difference in the biosensor response can be attributed to protein conformational or dynamical changes during covalent immobilization. The stability of the biosensors was tested at different temperatures and after different storage periods. The thermostability of the biosensors after incubation at 60°C demonstrated that the biosensor with covalently immobilized LOx retained a higher response compare with the adsorbed protein. Long-term stability experiments show a better residual activity of 40% for the covalently immobilized protein compared to 20% of residual activity for the adsorbed protein after 25 d storage. Covalent protein immobilization was superior compared to adsorption in preserving biosensor functionality over extended time period. PMID:25216450

  18. A comparative study of different protein immobilization methods for the construction of an efficient nano-structured lactate oxidase-SWCNT-biosensor.

    PubMed

    Pagán, Miraida; Suazo, Dámaris; Del Toro, Nicole; Griebenow, Kai

    2015-02-15

    We constructed lactate biosensors by immobilization of lactate oxidase (LOx) onto a single-walled carbon nanotube (SWCNT) electrode. The first step of the sensor construction was the immobilization of oxidized SWCNT onto a platinum electrode modified with 4-aminothiophenol (4-ATP). Two enzyme immobilization methods were used to construct the biosensors, i.e., covalent immobilization using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and physical adsorption. Atomic force microscopy (AFM) experiments confirmed the immobilization of SWCNT during the biosensor construction and X-ray photoelectron spectroscopy (XPS) experiments confirmed covalent immobilization of LOx onto the SWCNT in the first method. The biosensor based on covalent enzyme immobilization showed a sensitivity of 5.8 μA/mM, a linearity up to 0.12 mM of L-lactate, and a detection limit of 4.0 μM. The biosensor based on protein adsorption displayed a sensitivity of 9.4 μA/mM, retaining linearity up to 0.18 mM of L-lactate with a detection limit of 3.0 μM. The difference in the biosensor response can be attributed to protein conformational or dynamical changes during covalent immobilization. The stability of the biosensors was tested at different temperatures and after different storage periods. The thermostability of the biosensors after incubation at 60 °C demonstrated that the biosensor with covalently immobilized LOx retained a higher response compared with the adsorbed protein. Long-term stability experiments show a better residual activity of 40% for the covalently immobilized protein compared to 20% of residual activity for the adsorbed protein after 25 d storage. Covalent protein immobilization was superior compared to adsorption in preserving biosensor functionality over extended time period. PMID:25216450

  19. Parathyroid hormone-related protein overexpression protects goat mammary gland epithelial cells from calcium-sensing receptor activation-induced apoptosis.

    PubMed

    Li, Hui; Sun, Yongsen; Zheng, Huiling; Li, Lihui; Yu, Qian; Yao, Xiaotong

    2015-01-01

    Normal mammary gland epithelial cells and breast cancer cells express the calcium-sensing receptor (CaSR), which is the master regulator of systemic calcium metabolism. During lactation, activation of the CaSR in mammary epithelial cells downregulates parathyroid hormone-related protein (PTHrP) levels in milk and in the circulation, and increases calcium transport into milk. However, very little information is available on the role of CaSR in goat mammary gland epithelial cells (GMECs) apoptosis. In this investigation, the full-length cDNA of CaSR from Xinong Saanen dairy goats was cloned, which contains an open-reading frame of 3,258 bp encoding 1,085 amino acids with a predicted molecular weight of 121.0 kDa and an isoelectric point of 5.65. The amino acid sequence is highly homologous with sheep, and the goat CaSR gene is mapped to chromosome 1. Quantitative real-time PCR suggested that CaSR was predominantly expressed in the heart, kidney and mammary gland. Then, we found the stimulation of CaSR with its activator gadolinium chloride (GdCl3) contributed to increase CaSR mRNA levels in GMECs and simultaneously promoted cell apoptosis, and these effects were abrogated partially by NPS2390 which is an inhibitor of CaSR. We also demonstrated that Ca(2+) increased CaSR mRNA levels and induced GMECs apoptosis and restrained cell proliferation. In contrast, PTHrP overexpression protected GMECs from calcium-induced apoptosis, and promoted cell proliferation. In conclusion, these results suggest that PTHrP overexpression protects GMECs from CaSR activation-induced apoptosis. PMID:25266236

  20. Protein and Carbohydrate Interactions Alter Ruminal Fermentation, Digesta Characteristics, and Behavior in Lactating Dairy Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of altering dietary nonfiber carbohydrate complement and ruminally degradable protein was evaluated in an incomplete partially balanced Latin square design with a 2 x 2 factorial arrangement of treatments (trt) and two 21-d periods. Eight ruminally cannulated Holstein dairy cows were rand...

  1. Protein feeding and balancing for amino acids in lactating dairy cattle.

    PubMed

    Patton, Robert A; Hristov, Alexander N; Lapierre, Hélène

    2014-11-01

    This article summarizes the current literature as regards metabolizable protein (MP) and essential amino acid (EAA) nutrition of dairy cattle. Emphasis has been placed on research since the publication of the National Research Council Nutrient Requirements of Dairy Cattle, Seventh Revised Edition (2001). Postruminal metabolism of EAA is discussed in terms of the effect on requirements. This article suggests methods for practical application of MP and EAA balance in milking dairy cows. PMID:25245615

  2. Perinatal protein restriction affects milk free amino acid and fatty acid profile in lactating rats: potential role on pup growth and metabolic status.

    PubMed

    Martin Agnoux, Aurore; Antignac, Jean-Philippe; Boquien, Clair-Yves; David, Agnes; Desnots, Emmanuelle; Ferchaud-Roucher, Veronique; Darmaun, Dominique; Parnet, Patricia; Alexandre-Gouabau, Marie-Cécile

    2015-07-01

    Perinatal undernutrition affects not only fetal and neonatal growth but also adult health outcome, as suggested by the metabolic imprinting concept. Although maternal milk is the only channel through which nutrients are transferred from mother to offspring during the postnatal period, the impact of maternal undernutrition on milk composition is poorly understood. The present study investigates, in a rat model of nutritional programming, the effects of feeding an isocaloric, low-protein diet throughout gestation and lactation on milk composition and its possible consequences on offspring's growth and metabolic status. We used an integrated methodological approach that combined targeted analyses of macronutrients, free amino acid and fatty acid content throughout lactation, with an untargeted mass-spectrometric-based metabolomic phenotyping. Whereas perinatal dietary protein restriction failed to alter milk protein content, it dramatically decreased the concentration of most free amino acids at the end of lactation. Interestingly, a decrease of several amino acids involved in insulin secretion or gluconeogenesis was observed, suggesting that maternal protein restriction during the perinatal period may impact the insulinotrophic effect of milk, which may, in turn, account for the slower growth of the suckled male offspring. Besides, the decrease in sulfur amino acids may alter redox status in the offspring. Maternal undernutrition was also associated with an increase in milk total fatty acid content, with modifications in their pattern. Altogether, our results show that milk composition is clearly influenced by maternal diet and suggest that alterations in milk composition may play a role in offspring growth and metabolic programming. PMID:25935308

  3. A methodological approach to estimate the lactation curve and net energy and protein requirements of beef cows using nonlinear mixed-effects modeling.

    PubMed

    Albertini, T Z; Medeiros, S R; Torres, R A A; Zocchi, S S; Oltjen, J W; Strathe, A B; Lanna, D P D

    2012-11-01

    The objective of this study was to evaluate methods to predict the secretion of milk and net energy and protein requirements of beef cows (Bos indicus and B. taurus) after approximately 1 mo postpartum using nonlinear mixed-effect modeling (NLME). Twenty Caracu × Nellore (CN) and 10 Nellore (NL) cows were inseminated to Red Angus bulls, and 10 Angus × Nellore (AN) were bred to Canchim bulls. Cows were evaluated from just after calving (25 ± 11 d) to weaning (220 d). Milk yield was estimated by weighing calves before and after suckling (WSW) and by machine milking (MM) methods at 25, 52, 80, 109, 136, 164, 193, and 220 ± 11 d of lactation. Brody and simple linear equations were consecutively fitted to the data and compared using information criteria. For the Brody equation, a NLME model was used to estimate all lactation profiles incorporating different sources of variation (calf sex and breed of cow, cow as a nested random effect, and within-cow auto-correlation). The CV for the MM method (29%) was less than WSW (45%). Consequently, the WSW method was responsible for reducing the variance about 1.5 times among individuals, which minimized the ability to detect differences among cows. As a result, only milk yield MM data were used in the NLME models. The Brody equation provided the best fit to this dataset, and inclusion of a continuous autoregressive process improved fit (P < 0.01). Milk, energy and protein yield at the beginning of lactation were affected by cow genotype and calf sex (P < 0.001). The exponential decay of the lactation curves was affected only by genotype (P < 0.001). Angus × Nellore cows produced 15 and 48% more milk than CN and NL during the trial, respectively (P < 0.05). Caracu × Nellore cows produced 29% more milk than NL (P < 0.05). The net energy and net protein requirements for milk yield followed a similar ranking. Male calves stimulated their dams to produce 11.7, 11.4, and 11.9% more milk, energy and protein, respectively (P < 0

  4. Protein kinase activity in the rat mammary gland during pregnancy, lactation, and weaning: a correlation with growth but not with progesterone receptor levels.

    PubMed

    Sharoni, Y; Feldman, B; Teuerstein, I; Levy, J

    1984-11-01

    A protein kinase activity fraction was defined in cytosols and membranes of mammary tissue isolated from rats during pregnancy lactation, and weaning. By partial purification on DEAE-cellulose columns, it was shown that this protein kinase activity is cAMP independent and that its preferential substrate is casein and not histone. This protein kinase activity is inhibited by the bioflavonoid quercetin at doses that do not inhibit cAMP-dependent protein kinase activity. The enzyme requires Mg2+ and is inactive in the presence of 10 mM Ca+2; these properties distinguish this activity from casein kinase activity found in the Golgi fraction and involved in milk protein processing. By following the physiological cycle of mammary gland development during pregnancy, lactation, and weaning, we found a close correlation between proliferation, expressed as the DNA content per gland, and quercetin-inhibited cytosolic protein kinase activity. Moreover, changes in this phosphorylating activity preceded the glandular growth changes. There was a less significant correlation between the growth process and protein kinase activity in the membrane fraction. The cytosolic cAMP-dependent protein kinase activity showed (only partial) correlation with growth only during pregnancy. Cytosolic progesterone receptor levels in mammary tissue were used as an estrogenic marker. Tissue growth correlated with progesterone receptor levels during pregnancy, where estrogens are the predominant hormones affecting tissue proliferation. However, no such correlation was found during lactation and weaning, when PRL is the major hormone affecting mammary gland growth. These results suggest that quercetin-inhibitable protein kinase activity is not merely another estrogenic marker, but represents more general regulatory activity which might be connected to growth processes of breast tissue. PMID:6092041

  5. Effect of dietary cation-anion difference on performance of lactating dairy cows and stability of milk proteins.

    PubMed

    Martins, C M M R; Arcari, M A; Welter, K C; Netto, A S; Oliveira, C A F; Santos, M V

    2015-04-01

    Casein micelle stability is negatively correlated with milk concentrations of ionic calcium, which may change according to the metabolic and nutritional status of dairy cows. The present study aimed to evaluate the effect of dietary cation-anion difference (DCAD) on concentrations of casein subunits, whey proteins, ionic calcium, and milk heat and ethanol stability. Sixteen Holstein cows were distributed in 4 contemporary 4 × 4 Latin square designs, which consisted of 4 periods of 21 d and 4 treatments according to DCAD: 290, 192, 98, and -71 mEq/kg of dry matter (DM). The milk concentrations of ionic calcium and κ-casein were reduced as DCAD increased, whereas the milk urea nitrogen and β-lactoglobulin concentrations were increased. As a result of these alterations, the milk ethanol stability and milk stability during heating at 140 °C were increased linearly with increasing DCAD [Y = 74.87 (standard error = 0.87) + 0.01174 (standard error = 0.0025) × DCAD (mEq/kg of DM) and Y = 3.95 (standard error = 1.02) + 0.01234 (standard error = 0.0032) × DCAD (mEq/kg of DM), respectively]. In addition, 3.5% fat-corrected milk and fat, lactose, and total milk solids contents were linearly increased by 13.52, 8.78, 2.5, and 2.6%, respectively, according to DCAD increases from -71 to 290 mEq/kg of DM, whereas crude protein and casein content were linearly reduced by 4.83 and 4.49%, respectively. In conclusion, control of metabolic changes in lactating dairy cows to maintain blood acid-base equilibrium plays an important role in keeping milk stable to ethanol and during heat treatments. PMID:25622868

  6. Lactation performance of dairy cows fed yeast-derived microbial protein in low- and high-forage diets.

    PubMed

    Manthey, A K; Kalscheur, K F; Garcia, A D; Mjoun, K

    2016-04-01

    The objective of this study was to investigate the effect of substituting soybean meal products with yeast-derived microbial protein (YMP) on lactation performance in diets containing 2 forage-to-concentrate ratios. Sixteen Holstein cows (4 primiparous and 12multiparous) were randomly assigned to multiple 4×4 Latin squares with a 2×2 factorial arrangement of treatments. Diets contained low (LF; 45% of diet DM) or high forage (HF; 65% of diet DM) and YMP at 0 (NYMP) or 2.25% (WYMP) of the diet. The forage mix consisted of 67% corn silage and 33% alfalfa hay on a DM basis. No interactions of forage and YMP were noted for any of the production parameters measured. Feed efficiency (energy-corrected milk/dry matter intake) was greater for cows fed NYMP compared with WYMP. Regardless of the addition of YMP, cows fed LF had greater dry matter intake and produced more milk than cows fed HF. In addition, cows fed LF produced more energy-corrected milk than those fed HF. Milk fat percentage was lower in cows fed LF compared with HF, whereas fat yield was similar between forage concentrations. Fat yield tended to decrease with feeding YMP. Interactions of forage and YMP were observed for propionate concentration, acetate and propionate proportion, and acetate-to-propionate ratio. A tendency for an interaction of forage and YMP was also noted for ruminal pH. Cows fed HF diets had greater ruminal ammonia and butyrate concentrations, as well as proportion of butyrate. Arterial concentrations of Ile, Leu, Met, Thr, and Val were greater in cows fed LF. Cows fed NYMP had greater arterial concentrations of Ile, Lys, Trp, and Val than cows fed WYMP. Substitution of soybean proteins with YMP did not improve performance or feed efficiency of high-producing dairy cows regardless of the forage-to-concentrate ratio of the diet. PMID:26851859

  7. Rumen microorganisms, methane production, and microbial protein synthesis affected by mangosteen peel powder supplement in lactating dairy cows.

    PubMed

    Polyorach, Sineenart; Wanapat, Metha; Cherdthong, Anusorn; Kang, Sungchhang

    2016-03-01

    Four crossbred dairy cows (50 % Holstein-Friesian × 50 % Thai native), 404 ± 50.0 kg of body weight (4 years old) and 90 ± 5 day in milk with daily milk production of 9 ± 2.0 kg/day, were randomly assigned according to a 4 × 4 Latin square design to study the effect of mangosteen (Garcinia mangostana) peel powder (MSP) supplementation on rumen microorganisms, methane production, and microbial protein synthesis fed concentrate containing yeast fermented cassava chip protein (YEFECAP). The treatments were different levels of MSP supplementation at 0, 100, 200, and 300 g/head/day. Rice straw was used as a roughage source fed ad libitum, and concentrate containing YEFECAP at 200 g/kg concentrate was offered corresponding to concentrate-to-milk-yield ratio at 1:2. A quantitative real-time PCR approach was used to determine the population densities of ruminal microorganisms. The results revealed that supplementation of MSP did not affect on Fibrobactor succinogenes, Ruminococcus flavefaciens, and Ruminococcus albus (P > 0.05). However, total bacteria was linearly increased (P < 0.01) while methanogens and protozoal population were linearly decreased (P < 0.01) with increasing level of MSP supplementation. Increasing level of MSP supplement could decrease rumen methane production from 27.5 to 23.7 mmol/100 ml(3). Furthermore, cows that received MSP at 300 g/head/day had the highest microbial crude protein and efficiency of rumen microbial N synthesis (416.8 g/day and 16.2 g/kg organic matter truly digested in the rumen (OMDR), respectively). In conclusion, supplementation of MSP at 300 g/head/day with YEFECAP as a protein source in the concentrate mixture revealed an enhancement of rumen fermentation and methane reduction in lactating dairy cows. PMID:26885988

  8. Effect of dietary energy source and level on nutrient digestibility, rumen microbial protein synthesis, and milk performance in lactating dairy cows.

    PubMed

    Zhou, X Q; Zhang, Y D; Zhao, M; Zhang, T; Zhu, D; Bu, D P; Wang, J Q

    2015-10-01

    This study was conducted to examine the effects of dietary energy source and level on intake, digestion, rumen microbial protein synthesis, and milk production in lactating dairy cows, using corn stover as a forage source. Eight multiparous Holstein cows, 4 of which were fitted with rumen cannulas, were evaluated in a replicated 4 × 4 Latin square design, with each period lasting 21 d. The cows were randomly assigned into 4 treatment groups: low-energy (LE) ground corn (GC), LE steam-flaked corn (SFC), high-energy (HE) GC, and HE SFC. Changes to ruminal energy degradation rates were induced by feeding the cows diets of either finely ground corn or SFC as components of diets with the same total energy level. Milk yield, milk protein content and yield, and milk lactose yield all increased in response to higher levels of dietary energy, whereas contents of milk fat and lactose were unaffected. Cows fed HE diets had a higher crude microbial protein yield and total-tract apparent digestibility than those receiving LE diets. Milk yield, milk protein yield, and microbial protein yield were also higher when SFC replaced GC as the main energy source for lactating cows fed LE diets. These results suggest that an increased dietary energy level and ruminal degradation rate are beneficial to milk protein production, which we suggest is due to increased yields of microbial proteins, when cows are fed corn stover as a dietary forage source. PMID:26254527

  9. Cotransport of H+, lactate and H2O by membrane proteins in retinal pigment epithelium of bullfrog.

    PubMed

    Zeuthen, T; Hamann, S; la Cour, M

    1996-11-15

    1. The interaction between H+, lactate and H2O fluxes in the retinal membrane of the pigment epithelium from bullfrog Rana catesbiana was studied by means of ion-selective micro-electrodes. 2. Changes in intracellular pH and cell volume were recorded in response to abrupt changes in retinal solution concentration and/or osmolarity. 3. Two parallel pathways for water transport were identified across the retinal membrane, an osmotic one with a hydraulic water permeability of 3.2 x 10(-4) cm s-1 (osmol l-1)-1 and one which depended on the presence of lactate. 4. Addition of sodium lactate to the retinal solution caused cell shrinkages that were small compared with those produced by mannitol. The reflection coefficient for sodium lactate was 0.25. 5. Isosmotic replacement of Cl- with lactate caused an influx of water. Simultaneous acidification of the retinal solution from pH 7.4 to 6.4 enhanced the effect. The influx of water could proceed against osmotic gradients elicited by mannitol. 6. The interdependence of the fluxes of H+, lactate and H2O can be described as cotransport: the fluxes had a fixed ratio of about 109 mmol of lactic acid per litre of water, the flux of one species was able to energize the flux of the other two, and the fluxes exhibited saturation for increasing driving forces. 7. The Gibbs equation gives an accurate quantitative description of these coupled fluxes. PMID:8951707

  10. Lactate dehydrogenase-elevating virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Lactate dehydrogenase-elevating virus (LDV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biologic...

  11. The effect of G protein-coupled receptor kinase 2 (GRK2) on lactation and on proliferation of mammary epithelial cells from dairy cows.

    PubMed

    Hou, Xiaoming; Hu, Hongliu; Lin, Ye; Qu, Bo; Gao, Xuejun; Li, Qingzhang

    2016-07-01

    Milk protein is an important component of milk and a nutritional source for human consumption. To better understand the molecular events underlying synthesis of milk proteins, the global gene expression patterns in mammary glands of dairy cow with high-quality milk (>3% milk protein; >3.5% milk fat) and low-quality milk (<3% milk protein; <3.5% milk fat) were examined via digital gene expression study. A total of 139 upregulated and 66 downregulated genes were detected in the mammary tissues of lactating cows with high-quality milk compared with the tissues of cows with low-quality milk. A pathway enrichment study of these genes revealed that the top 5 pathways that were differentially affected in the tissues of cows with high- versus low-quality milk involved metabolic pathways, cancer, cytokine-cytokine receptor interactions, regulation of the actin cytoskeleton, and insulin signaling. We also found that the G protein-coupled receptor kinase 2 (GRK2) was one of the most highly upregulated genes in lactating mammary tissue with low-quality milk compared with tissue with high-quality milk. The knockdown of GRK2 in cultured bovine mammary epithelial cells enhanced CSN2 expression and activated signaling molecules related to translation, including protein kinase B, mammalian target of rapamycin, and p70 ribosomal protein S6 kinase 1 (S6K1), whereas overexpression of GRK2 had the opposite effects. However, expression of genes involved in the mitogen-activated protein kinase pathway was positively regulated by GRK2. Therefore, GRK2 seems to act as a negative mediator of milk-protein synthesis via the protein kinase B-mammalian target of rapamycin signaling axis. Furthermore, GRK2 may negatively control milk-protein synthesis by activating the mitogen-activated protein kinase pathway in dairy cow mammary epithelial cells. PMID:27132107

  12. Low degradable protein supply to increase nitrogen efficiency in lactating dairy cows and reduce environmental impacts at barn level.

    PubMed

    Edouard, N; Hassouna, M; Robin, P; Faverdin, P

    2016-02-01

    Generally, <30% of dairy cattle's nitrogen intake is retained in milk. Large amounts of nitrogen are excreted in manure, especially in urine, with damaging impacts on the environment. This study explores the effect of lowering dietary degradable nitrogen supplies--while maintaining metabolisable protein--on dairy cows' performance, nitrogen use efficiency and gas emissions (NH3, N2O, CH4) at barn level with tied animals. Two dietary N concentrations (CP: 12% DM for LowN; 18% DM for HighN) were offered to two groups of three lactating dairy cows in a split-plot design over four periods of 2 weeks. Diets were formulated to provide similar metabolisable protein supply, with degradable N either in deficit or in excess (PDIN of 84 and 114 g/kg DM for LowN and HighN, respectively). Cows ingested 0.8 kg DM/day less on the LowN diet, which was also 2.5% less digestible. Milk yield and composition were not significantly affected. N exported in milk was 5% lower (LowN: 129 g N/day; HighN: 136 g N/day; P<0.001) but milk protein yield was not significantly affected (LowN: 801 g/day; HighN: 823 g/day; P=0.10). Cows logically ingested less nitrogen on the LowN diet (LowN: 415 g N/day; HighN: 626 g N/day; P<0.001) resulting in a higher N use efficiency (N milk/N intake; LowN: 0.31; HighN: 0.22; P<0.001). N excreted in urine was almost four times lower on the LowN diet (LowN: 65 g N/day; HighN: 243 g N/day; P<0.001) while urinary urea N concentration was eightfold lower (LowN: 4.6 g/l; HighN: 22.9 g/l; P<0.001). Ammonia emission (expressed in g/h in order to remove periods of the day with potential interferences with volatile molecules from feed) was also lower on the LowN diet (LowN: 1.03 g/h per cow; HighN: 1.25 g/h per cow; P<0.05). Greenhouse gas emissions (N2O and CH4) at barn level were not significantly affected by the amount of dietary N. Offering low amounts of degradable protein with suitable metabolisable protein amounts to cattle improved nitrogen use efficiency and

  13. Parathyroid Hormone-Related Protein Analogs as Osteoporosis Therapies.

    PubMed

    Esbrit, Pedro; Herrera, Sabina; Portal-Núñez, Sergio; Nogués, Xavier; Díez-Pérez, Adolfo

    2016-04-01

    The only bone anabolic agent currently available for osteoporosis treatment is parathyroid hormone (PTH)-either its N-terminal 1-34 fragment or the whole molecule of 1-84 aminoacids-whose intermittent administration stimulates new bone formation by targeting osteoblastogenesis and osteoblast survival. PTH-related protein (PTHrP) is an abundant factor in bone which shows N-terminal homology with PTH and thus exhibits high affinity for the same PTH type 1 receptor in osteoblasts. Therefore, it is not surprising that intermittently administered N-terminal PTHrP peptides induce bone anabolism in animals and humans. Furthermore, the C-terminal region of PTHrP also elicits osteogenic features in vitro in osteoblastic cells and in various animal models of osteoporosis. In this review, we discuss the current concepts about the cellular and molecular mechanisms whereby PTHrP may induce anabolic actions in bone. Pre-clinical studies and clinical data using N-terminal PTHrP analogs are also summarized, pointing to PTHrP as a promising alternative to current bone anabolic therapies. PMID:26259869

  14. Effects of protein level, methionine supplementation and carbohydrate type of the diet on liver lipid and plasma free threonine contents in the lactating rat.

    PubMed

    Leclerc, J; Chanussot, B; Miller, M L; Poisson, J P; Belleville, J

    1989-01-01

    Eight groups of 13-15 female rats were fed purified diets after littering. Four groups received a low protein (8% casein) diet (groups 8) and the others, a normal protein (20% casein) diet (groups 20). Carbohydrates were supplied either as starch (groups S) or as starch plus 40% fructose (groups F). Half the animals received a 0.4% methionine supplementation (groups M). Four or five dams per group were sacrificed on days 2, 7 and 14 after littering. The diet intake was increased by methionine supplementation, substitution of starch for fructose and increased protein content, mainly during the second week of lactation. This influenced weight variation of the dams and litter growth. On all days, the plasma levels of cholesterol esters, triglycerides and phospholipids were positively correlated with the dietary protein level. On days 7 and 14, the liver neutral lipid content was increased in rats fed the low protein diets supplemented with methionine (groups 8SM and 8FM) and the normal protein diets containing 40% fructose (groups 20F and 20FM). The plasma free threonine content was positively correlated with the protein level in the diet. On day 14, rats fed a low protein diet had a threonine deficiency, except those in groups 8S and 8F. The plasma free threonine content of these rats was not reduced, possibly due to an impaired utilization of this amino acid. The liver lipidosis observed during lactation, in contrast to that observed during growth with a low protein diet, was not due to a threonine deficiency. PMID:2511852

  15. Corn steep liquor and fermented ammoniated condensed whey as protein sources for lactating cows and yearling heifers grazing winter native range

    SciTech Connect

    Wagner, J.J.; Lusby, K.S.; Horn, G.W.; Dvorak, M.J.

    1982-06-01

    Corn steep liquor (CSL) and fermented ammoniated condensed whey (FACW) were compared to cottonseed meal (CSM) as protein sources for wintering 61 lactating first-calf Hereford heifers and 32 yearling Hereford heifers on native range. Cattle were allotted by weight and individually fed 6 days per week for 12 weeks one of four protein treatments: negative control (NC), positive control (PC), CSL and FACW to provide .7, 1.5, .15 and 1.5 lb crude protein (CP) per day, respectively, to the lacating heifers and .2, .4, .4 and .4lb cP per day, respectively, to the yearling heifers. CMS was supplied in the CSL and FACW treatments at the same level as in the negative control. Lactating heifers fed the NC lost more (P less than .005) weight and body condition (120 lb and 1.6 units) than those fed the PC (45.8 lb and .9 units). Weight and condition losses were similar (P more than .05) for lactating heifers fed PC, CSL and FACW. Yearling heifers fed the NC lost more (P less than .005) weight than those fed the PC (49.4 vs 10.6 lb). Yearling heifers fed CSL and FACW gained more (P less than .005) weight than those fed the PC (17.6 and 9.3 vs - 10.6 lb). Feeding CSL resulted in signficantly lower rumen pH, lower ruminal acetate and higher ruminal butyrate, isovalerate and caproate levels than did feeding either control. Supplementing with FACW produced significantly lower rumen pH, higher rumen ammonia and soluble carbohydrate levels, lower ruminal acetate, and higher ruminal propionate and butyrate concentrations than did either control supplement. Corn steep liquor and FDCW appear to be effective protein sources for cows and heifers grazing winter native range.

  16. Vascular effects of parathyroid hormone and parathyroid hormone-related protein in the split hydronephrotic rat kidney.

    PubMed Central

    Endlich, K; Massfelder, T; Helwig, J J; Steinhausen, M

    1995-01-01

    1. The effects of locally applied parathyroid hormone-related protein (PTHRP), a putative autocrine/paracrine hormone, on vascular diameters and glomerular blood flow (GBF) in the split hydronephrotic rat kidney were studied. As PTHRP interacts with parathyroid hormone (PTH) receptors in all tissues tested so far, the effects of PTHRP were compared with those of PTH. 2. Preglomerular vessels dilated in a concentration- and time-dependent manner that was almost identical for PTH and PTHRP. A significant preglomerular vasodilation (5-17%) occurred at a threshold concentration of 10(-10) mol l-1 PTH or PTHRP, which raised GBF by 20 +/- 2 and 31 +/- 4%, respectively (means +/- S.E.M., n = 6). PTH or PTHRP (10(-7) mol l-1) increased preglomerular diameters (11-36%) and GBF (60 +/- 10 and 70 +/- 8%, respectively) to near maximum. The most prominent dilatation was located at the interlobular artery and at the proximal afferent arteriole. 3. Efferent arterioles were not affected by either PTH or PTHRP. 4. Estimated concentrations of half-maximal response (EC50) for preglomerular vasodilatation and GBF increase were in the nanomolar to subnanomolar range. 5. After inhibition of angiotensin I-converting enzyme by 2 x 10(-6) mol kg-1 quinapril I.V. (n = 6), 10(-8) mol l-1 PTHRP dilated preglomerular vessels and efferent arterioles (9 +/- 1% proximal and 6 +/- 1% distal). 6. We conclude that the renal vasculature of the hydronephrotic kidney is highly sensitive to vasodilatation by PTH and PTHRP, which, in addition, may constrict efferent arterioles by stimulating renin release.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7650615

  17. Short communication: Effect of dietary manipulation of crude protein content and nonfibrous-to-fibrous-carbohydrate ratio on energy balance in early-lactation dairy cows.

    PubMed

    Whelan, S J; Mulligan, F J; Gath, V; Flynn, B; Pierce, K M

    2014-11-01

    Disparities between nutrient intake and demand often result in a state of negative energy balance (EB) in the early-lactation dairy cow. Reducing dietary crude protein (CP) content and providing glucogenic nutrients may overcome this issue. This study evaluates whether or not offering a diet lower in CP and higher in nonfiber carbohydrates (LP-NFC) can improve EB and the metabolic status of the early-lactation dairy cow compared with a diet higher in CP and fibrous carbohydrates (HP-FC). Twenty Holstein-Friesian dairy cows were assigned to 1 of 2 dietary treatments in a randomized block design. Diets were isoenergetic (6.57 MJ of net energy for lactation) and formulated to contain 15% CP and 6% starch (HP-FC), or 12% CP and 28% starch (LP-NFC) and were offered for the first 63 d of lactation. Intake and milk yield were determined daily, whereas milk and blood samples, weights, and body condition scores were collected weekly. Intakes (mean ± standard errors of the mean, SEM) of dry matter (17.4 ± 0.6 kg/d) and energy (113.0 ± 4.6 MJ of net energy for lactation) were not different between treatments. However, the HP-FC group had a higher milk yield (31.8 vs. 28.9 ± 1.4 kg/d) and a lower EB compared with the LP-NFC group. Blood urea N concentration (3.5 vs. 1.8 ± 0.2 mmol/L) was higher, whereas bilirubin (6.0 vs. 6.7 ± 0.2 mmol/L) and β-hydroxybutyrate concentrations (0.7 vs. 0.8 ± 0.05 mmol/L) were lower in the HP-FC group compared with the LP-NFC group. These data suggest that EB can be improved during early lactation through the manipulation of milk output by offering a lower CP, higher NFC diet. PMID:25173467

  18. Response of lactating cows to methionine or methionine plus lysine added to high protein diets based on alfalfa and heated soybeans.

    PubMed

    Armentano, L E; Bertics, S J; Ducharme, G A

    1997-06-01

    Lactation diets based on wilted alfalfa silage and heated whole soybeans are common in the midwestern US. We examined the milk production response of multiparous Holstein cows to the addition of ruminally protected methionine at two percentages to a basal total mixed ration. An additional total mixed ration included both methionine and lysine supplementation. Sixteen Holstein cows in early lactation were used in a replicated 4 x 4 Latin square design with 21-d periods. Milk production, milk composition, and dry matter intake were determined for the last 5 d of each period. Milk production (41.5 kg/d), dry matter intake (25.9 kg/d), and milk fat concentration (3.26%) were unaffected by the supplementation of amino acids. The addition of methionine increased milk protein concentration and yield linearly. Each gram of methionine increased milk protein yield by 4 g, and milk protein concentration increased from 2.89 to 2.99% with the addition of 10.5 g/d of methionine. The proportion of casein N in total milk N was unaffected by treatment. The addition of lysine did not elicit a response. Total mixed rations based on alfalfa haylage, heated soybeans, and animal proteins were clearly limited by their methionine content but were adequate in their lysine content. PMID:9201591

  19. Brain CRF-binding protein modulates aspects of maternal behavior under stressful conditions and supports a hypo-anxious state in lactating rats.

    PubMed

    Klampfl, Stefanie M; Schramm, Milena M; Stinnett, Gwen S; Bayerl, Doris S; Seasholtz, Audrey F; Bosch, Oliver J

    2016-08-01

    Reduced corticotropin-releasing factor (CRF) receptor activation in the postpartum period is essential for adequate maternal behavior. One of the factors contributing to this hypo-activity might be the CRF-binding protein (CRF-BP), which likely reduces the availability of free extracellular CRF/urocortin 1. Here, we investigated behavioral effects of acute CRF-BP inhibition using 5μg of CRF(6-33) administered either centrally or locally within different parts of the bed nucleus of the stria terminalis (BNST) in lactating rats. Additionally, we assessed CRF-BP expression in the BNST comparing virgin and lactating rats. Central CRF-BP inhibition increased maternal aggression during maternal defense but did not affect maternal care or anxiety-related behavior. CRF-BP inhibition in the medial-posterior BNST had no effect on maternal care under non-stress conditions but impaired the reinstatement of maternal care following stressor exposure. Furthermore, maternal aggression, particularly threat behavior, and anxiety-related behavior were elevated by CRF-BP inhibition in the medial-posterior BNST. In the anterior-dorsal BNST, CRF-BP inhibition increased only non-maternal behaviors following stress. Finally, CRF-BP expression was higher in the anterior compared to the posterior BNST but was not different between virgin and lactating rats in either region. Our study demonstrates a key role of the CRF-BP, particularly within the BNST, in modulating CRF's impact on maternal behavior. The CRF-BP is important for the reinstatement of maternal care after stress, for modulating threat behavior during an aggressive encounter and for maintaining a hypo-anxious state during lactation. Thus, the CRF-BP likely contributes to the postpartum-associated down-regulation of the CRF system in a brain region-dependent manner. PMID:27368148

  20. The promotion of osteochondral repair by combined intra-articular injection of parathyroid hormone-related protein and implantation of a bi-layer collagen-silk scaffold.

    PubMed

    Zhang, Wei; Chen, Jialin; Tao, Jiadong; Hu, Changchang; Chen, Longkun; Zhao, Hongshi; Xu, Guowei; Heng, Boon C; Ouyang, Hong Wei

    2013-08-01

    The repair of osteochondral defects can be enhanced with scaffolds but is often accompanied with undesirable terminal differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Parathyroid hormone-related protein (PTHrP) has been shown to inhibit aberrant differentiation, but administration at inappropriate time points would have adverse effects on chondrogenesis. This study aims to develop an effective tissue engineering strategy by combining PTHrP and collagen-silk scaffold for osteochondral defect repair. The underlying mechanisms of the synergistic effect of combining PTHrP administration with collagen-silk scaffold implantation for rabbit knee joint osteochondral defect repair were investigated. In vitro studies showed that PTHrP treatment significantly reduced Alizarin Red staining and expression of terminal differentiation-related markers. This is achieved in part through blocking activation of the canonical Wnt/β-catenin signaling pathway. For the in vivo repair study, intra-articular injection of PTHrP was carried out at three different time windows (4-6, 7-9 and 10-12 weeks) together with implantation of a bi-layer collagen-silk scaffold. Defects treated with PTHrP at the 4-6 weeks time window exhibited better regeneration (reconstitution of cartilage and subchondral bone) with minimal terminal differentiation (hypertrophy, ossification and matrix degradation), as well as enhanced chondrogenesis (cell shape, Col2 and GAG accumulation) compared with treatment at other time windows. Furthermore, the timing of PTHrP administration also influenced PTHrP receptor expression, thus affecting the treatment outcome. Our results demonstrated that intra-articular injection of PTHrP at 4-6 weeks post-injury together with collagen-silk scaffold implantation is an effective strategy for inhibiting terminal differentiation and enhancing chondrogenesis, thus improving cartilage repair and regeneration in a rabbit model. PMID:23702148

  1. Effect of dietary starch level and high rumen-undegradable protein on endocrine-metabolic status, milk yield, and milk composition in dairy cows during early and late lactation.

    PubMed

    Piccioli-Cappelli, F; Loor, J J; Seal, C J; Minuti, A; Trevisi, E

    2014-12-01

    Diet composition defines the amount and type of nutrients absorbed by dairy cows. Endocrine-metabolic interactions can influence these parameters, and so nutrient availability for the mammary gland can significantly vary and affect milk yield and its composition. Six dairy cows in early and then late lactation received, for 28 d in a changeover design, 2 diets designed to provide, within the same stage of lactation, similar amounts of rumen fermentable material but either high starch plus sugar (HS) content or low starch plus sugar content (LS). All diets had similar dietary crude protein and calculated supply of essential amino acids. Dry matter intake within each stage of lactation was similar between groups. Milk yield was similar between groups in early lactation, whereas a higher milk yield was observed in late lactation when feeding HS. At the metabolic level, the main difference observed between the diets in both stages of lactation was lower blood glucose in cows fed LS. The lower glucose availability during consumption of LS caused substantial modifications in the circulating and postprandial pattern of metabolic hormones. Feeding LS versus HS resulted in an increase in the ratio of bovine somatotropin to insulin. This increased mobilization of lipid reserves resulted in higher blood concentrations of nonesterified fatty acids and β-hydroxybutyrate, which contributed to the higher milk fat content in both stages of lactation in the LS group. This greater recourse to body fat stores was confirmed by the greater loss of body weight during early lactation and the slower recovery of body weight in late lactation in cows fed LS. The lower insulin to glucagon ratio observed in cows fed LS in early and late lactation likely caused an increase in hepatic uptake and catabolism of amino acids, as confirmed by the higher blood urea concentrations. Despite the higher catabolism of amino acids in LS in early lactation, similar milk protein output was observed for both

  2. Parathyroid Hormone–Related Protein Promotes Epithelial–Mesenchymal Transition

    PubMed Central

    Ardura, Juan Antonio; Rayego-Mateos, Sandra; Rámila, David; Ruiz-Ortega, Marta

    2010-01-01

    Epithelial–mesenchymal transition (EMT) is an important process that contributes to renal fibrogenesis. TGF-β1 and EGF stimulate EMT. Recent studies suggested that parathyroid hormone–related protein (PTHrP) promotes fibrogenesis in the damaged kidney, apparently dependent on its interaction with vascular endothelial growth factor (VEGF), but whether it also interacts with TGF-β and EGF to modulate EMT is unknown. Here, PTHrP(1-36) increased TGF-β1 in cultured tubuloepithelial cells and TGF-β blockade inhibited PTHrP-induced EMT-related changes, including upregulation of α-smooth muscle actin and integrin-linked kinase, nuclear translocation of Snail, and downregulation of E-cadherin and zonula occludens-1. PTHrP(1-36) also induced EGF receptor (EGFR) activation; inhibition of protein kinase C and metalloproteases abrogated this activation. Inhibition of EGFR activation abolished these EMT-related changes, the activation of ERK1/2, and upregulation of TGF-β1 and VEGF by PTHrP(1-36). Moreover, inhibition of ERK1/2 blocked EMT induced by either PTHrP(1-36), TGF-β1, EGF, or VEGF. In vivo, obstruction of mouse kidneys led to changes consistent with EMT and upregulation of TGF-β1 mRNA, p-EGFR protein, and PTHrP. Taken together, these data suggest that PTHrP, TGF-β, EGF, and VEGF might cooperate through activation of ERK1/2 to induce EMT in renal tubuloepithelial cells. PMID:19959711

  3. Effects of parathyroid hormone-related protein and macrophage inflammatory protein-1α in Jurkat T-cells on tumor formation in vivo and expression of apoptosis regulatory genes in vitro

    PubMed Central

    Shu, Sherry T.; Dirksen, Wessel P.; Lanigan, Lisa G.; Martin, Chelsea K.; Thudi, Nanda K.; Werbeck, Jillian L.; Fernandez, Soledad A.; Hildreth, Blake E.; Rosol, Thomas J.

    2012-01-01

    Parathyroid hormone-related protein (PTHrP) and macrophage inflammatory protein-1α (MIP-1α) have been implicated in the pathogenesis of adult T-cell leukemia/lymphoma, but their effects on T-cells have not been well studied. Here we analyzed the functions of PTHrP and MIP-1α on T-cell growth and death both in vitro and in vivo by overexpressing either factor in human Jurkat T-cells. PTHrP or MIP-1α did not affect Jurkat cell growth in vitro, but PTHrP increased their sensitivity to apoptosis. Importantly, PTHrP and MIP-1α decreased both tumor incidence and growth in vivo. To investigate possible mechanisms, polymerase chain reaction (PCR) arrays and real-time reverse transcription (RT)-PCR assays were performed. Both PTHrP and MIP-1α increased the expression of several factors including signal transducer and activator of transcription 4, tumor necrosis factor α, receptor activator of nuclear factor κB ligand and death-associated protein kinase 1, and decreased the expression of inhibitor of DNA binding 1, interferon γ and CD40 ligand in Jurkat cells. In addition, MIP-1α also increased the expression of transcription factor AP-2α and PTHrP increased expression of the vitamin D3 receptor. These data demonstrate that PTHrP and MIP-1α exert a profound antitumor effect presumably by increasing the sensitivity to apoptotic signals through modulation of transcription and apoptosis factors in T-cells. PMID:21942940

  4. Effect of replacing soybean meal protein with protein from upland cottonseed, Pima cottonseed, or extruded Pima cottonseed on production of lactating dairy cows.

    PubMed

    Broderick, G A; Kerkman, T M; Sullivan, H M; Dowd, M K; Funk, P A

    2013-04-01

    Pima cotton production is increasing in the United States, but Pima cottonseed generally contains higher concentrations of the antinutritive pigment gossypol than conventional upland cottonseed. Heating promotes the reaction of gossypol with protein, reducing gossypol absorption and toxicity. The objective of this study was to assess the nutritional value for dairy cattle of Pima cottonseed cake (PCSC) that was heated and oil largely removed by an experimental extrusion process, compared with upland cottonseed (UCS) and Pima cottonseed (PCS). The PCS had greater crude protein (CP) and ether extract, less neutral detergent fiber (NDF) and acid detergent fiber (ADF), similar total gossypol, but higher (-)-gossypol isomer compared with UCS. Extrusion reduced lipid content by 73%, increased concentrations of CP, NDF, and ADF, and reduced total gossypol, (+)-gossypol, and (-)-gossypol in PCSC versus PCS. Forty lactating Holsteins (8 with ruminal cannulas) were blocked by days in milk into 5 squares in a replicated, incomplete 8 × 8 Latin square, and were fed diets containing, on a dry matter (DM) basis, 30% alfalfa silage, 31% corn silage, 21 to 25% high-moisture corn, and about 15% CP. Diets were fed as total mixed rations for ad libitum intake. Supplemental CP was from (1) solvent soybean meal (SSBM) only or 50% from SSBM plus 50% from (2) UCS, (3) PCS, (4) PCSC, (5) UCS plus PCS, and (6) UCS plus PCSC, or (7) 50% from expeller soybean meal (ESBM) plus 50% from PCS, and (8) 50% from ESBM plus 50% from PCSC. Periods were 4 wk long (total of 16 wk); production data were collected over the last 2 wk and blood and ruminal samples were taken on d 28 of each period. Data were analyzed using Proc Mixed of SAS (SAS Institute Inc., Cary, NC). Diet affected dry matter intake, with greatest intake on diet 6 and lowest intake on diets 1 and 3. The highest milk fat content was observed on diet 5 and the greatest fat yield on diet 7; fat content and yield were lowest on diet 1

  5. Maternal protein restriction during pregnancy and lactation alters central leptin signalling, increases food intake, and decreases bone mass in 1 year old rat offspring.

    PubMed

    Qasem, Rani J; Li, Jing; Tang, Hee Man; Pontiggia, Laura; D'mello, Anil P

    2016-04-01

    The effects of perinatal nutrition on offspring physiology have mostly been examined in young adult animals. Aging constitutes a risk factor for the progressive loss of metabolic flexibility and development of disease. Few studies have examined whether the phenotype programmed by perinatal nutrition persists in aging offspring. Persistence of detrimental phenotypes and their accumulative metabolic effects are important for disease causality. This study determined the effects of maternal protein restriction during pregnancy and lactation on food consumption, central leptin sensitivity, bone health, and susceptibility to high fat diet-induced adiposity in 1-year-old male offspring. Sprague-Dawley rats received either a control or a protein restricted diet throughout pregnancy and lactation and pups were weaned onto laboratory chow. One-year-old low protein (LP) offspring exhibited hyperphagia. The inability of an intraperitoneal (i.p.) leptin injection to reduce food intake indicated that the hyperphagia was mediated by decreased central leptin sensitivity. Hyperphagia was accompanied by lower body weight suggesting increased energy expenditure in LP offspring. Bone density and bone mineral content that are negatively regulated by leptin acting via the sympathetic nervous system (SNS), were decreased in LP offspring. LP offspring did not exhibit increased susceptibility to high fat diet induced metabolic effects or adiposity. The results presented here indicate that the programming effects of perinatal protein restriction are mediated by specific decreases in central leptin signalling to pathways involved in the regulation of food intake along with possible enhancement of different CNS leptin signalling pathways acting via the SNS to regulate bone mass and energy expenditure. PMID:26763577

  6. FGF-21 and skeletal remodeling during and after lactation in C57BL/6J mice.

    PubMed

    Bornstein, Sheila; Brown, Sue A; Le, Phuong T; Wang, Xunde; DeMambro, Victoria; Horowitz, Mark C; MacDougald, Ormond; Baron, Roland; Lotinun, Sutada; Karsenty, Gerard; Wei, Wei; Ferron, Mathieu; Kovacs, Christopher S; Clemmons, David; Wan, Yihong; Rosen, Clifford J

    2014-09-01

    Lactation is associated with significant alterations in both body composition and bone mass. Systemic and local skeletal factors such as receptor activator of nuclear factor κ-B ligand (RANKL), PTHrP, calcitonin, and estrogen are known to regulate bone remodeling during and after lactation. Fibroblast growth factor 21 (FGF-21) may function as an endocrine factor to regulate body composition changes during lactation by inducing gluconeogenesis and fatty acid oxidation. In this study, we hypothesized that the metabolic changes during lactation were due in part to increased circulating FGF-21, which in turn could accentuate bone loss. We longitudinally characterized body composition in C57BL/6J (B6) mice during (day 7 and day 21 of lactation) and after normal lactation (day 21 postlactation). At day 7 of lactation, areal bone density declined by 10% (P < .001), bone resorption increased (P < .0001), percent fat decreased by 20%, energy expenditure increased (P < .01), and markers of brown-like adipogenesis were suppressed in the inguinal depot and in preformed brown adipose tissue. At day 7 of lactation there was a 2.4-fold increase in serum FGF-21 vs baseline (P < .0001), a 8-fold increase in hepatic FGF-21 mRNA (P < .03), a 2-fold increase in undercarboxylated osteocalcin (Glu13 OCn) (P < .01), and enhanced insulin sensitivity. Recovery of total areal bone density was noted at day 21 of lactation, whereas the femoral trabecular bone volume fraction was still reduced (P < .01). Because FGF-21 levels rose rapidly at day 7 of lactation in B6 lactating mice, we next examined lactating mice with a deletion in the Fgf21 gene. Trabecular and cortical bone masses were maintained throughout lactation in FGF-21(-/-) mice, and pup growth was normal. Compared with lactating control mice, lactating FGF-21(-/-) mice exhibited an increase in bone formation, but no change in bone resorption. In conclusion, in addition to changes in calciotropic hormones, systemic FGF-21 plays a

  7. Effects of Protein Level and Mangosteen Peel Pellets (Mago-pel) in Concentrate Diets on Rumen Fermentation and Milk Production in Lactating Dairy Crossbreds

    PubMed Central

    Norrapoke, T.; Wanapat, M.; Wanapat, S.

    2012-01-01

    Four, lactating dairy crossbreds (50%×50% Holstein Friesian×Native Zebu cattle) were randomly assigned according to a 2×2 factorial arrangement (two protein levels and two levels of mangosteen peel pellets (Mago-pel)) in a 4×4 Latin square design to receive four dietary treatments. All cows received concentrate at a proportion of 1 kg concentrate per 2 kg of milk yield, and urea-treated 5% rice straw (UTRS) was given ad libitum. It was found that total dry matter intakes, nutrient digestibility, ruminal pH and NH3-N concentrations were not affected (p>0.05) by treatments. Concentrations of ruminal pH and NH3-N were not affected by dietary treatments although the concentration of BUN varied significantly (p<0.05) between protein levels (p<0.05). The populations of rumen bacteria and fungal zoospores did not differ among treatments (p>0.05); however, the population of protozoa was decreased (p<0.05) when cows received Mago-pel supplementation. The composition of the population of bacteria, identified by real-time PCR technique, including total bacteria, methanogens, Fibrobacter succinogenes and Ruminococcus albus was similar (p>0.05) among dietary treatments (p>0.05); however, copy numbers of Ruminococcus flavefaciens was increased when protein level increased (p<0.05). Microbial protein synthesis, in terms of both quantity and efficiency, was enriched by Mago-pel supplementation. Milk yield was greatest in cows fed UTRS based diets with concentrate containing protein at 16% CP with Mago-pel, but were lowest without Mago-pel (p<0.05). In addition, protein level and supplementation of Mago-pel did not affect (p>0.05) milk composition except solids-not-fat which was higher in cows fed the diet with 19% CP. Therefore, feeding a concentrate containing 16% CP together with 300 g/hd/d Mago-pel supplementation results in changes in rumen fermentation and microbial population and improvements in milk production in lactating dairy crossbreds fed on UTRS. PMID:25049652

  8. Lactate-Dehydrogenase 5 is overexpressed in non-small cell lung cancer and correlates with the expression of the transketolase-like protein 1

    PubMed Central

    2010-01-01

    Aims As one of the five Lactate dehydrogenase (LDH) isoenzymes, LDH5 has the highest efficiency to catalyze pyruvate transformation to lactate. LDH5 overexpression in cancer cells induces an upregulated glycolytic metabolism and reduced dependence on the presence of oxygen. Here we analyzed LDH5 protein expression in a well characterized large cohort of primary lung cancers in correlation to clinico-pathological data and its possible impact on patient survival. Methods Primary lung cancers (n = 269) and non neoplastic lung tissue (n = 35) were tested for LDH5 expression by immunohistochemistry using a polyclonal LDH5 antibody (ab53010). The results of LDH5 expression were correlated to clinico-pathological data as well as to patient's survival. In addition, the results of the previously tested Transketolase like 1 protein (TKTL1) expression were correlated to LDH5 expression. Results 89.5% (n = 238) of NSCLC revealed LDH5 expression whereas LDH5 expression was not detected in non neoplastic lung tissues (n = 34) (p < 0.0001). LDH5 overexpression was associated with histological type (adenocarcinoma = 57%, squamous cell carcinoma = 45%, large cell carcinoma = 46%, p = 0.006). No significant correlation could be detected with regard to TNM-stage, grading or survival. A two sided correlation between the expression of TKTL1 and LDH5 could be shown (p = 0.002) within the overall cohort as well as for each grading and pN group. A significant correlation between LDH5 and TKTL1 within each histologic tumortype could not be revealed. Conclusions LDH5 is overexpressed in NSCLC and could hence serve as an additional marker for malignancy. Furthermore, LDH5 correlates positively with the prognostic marker TKTL1. Our results confirm a close link between the two metabolic enzymes and indicate an alteration in the glucose metabolism in the process of malignant transformation. PMID:20385008

  9. Insulin, CCAAT/Enhancer-Binding Proteins and Lactate Regulate the Human 11β-Hydroxysteroid Dehydrogenase Type 2 Gene Expression in Colon Cancer Cell Lines

    PubMed Central

    Alikhani-Koupaei, Rasoul; Ignatova, Irena D.; Guettinger, Andreas; Frey, Felix J.; Frey, Brigitte M.

    2014-01-01

    11β-Hydroxysteroid dehydrogenases (11beta-HSD) modulate mineralocorticoid receptor transactivation by glucocorticoids and regulate access to the glucocorticoid receptor. The isozyme 11beta-HSD2 is selectively expressed in mineralocorticoid target tissues and its activity is reduced in various disease states with abnormal sodium retention and hypertension, including the apparent mineralocorticoid excess. As 50% of patients with essential hypertension are insulin resistant and hyperinsulinemic, we hypothesized that insulin downregulates the 11beta-HSD2 activity. In the present study we show that insulin reduced the 11beta-HSD2 activity in cancer colon cell lines (HCT116, SW620 and HT-29) at the transcriptional level, in a time and dose dependent manner. The downregulation was reversible and required new protein synthesis. Pathway analysis using mRNA profiling revealed that insulin treatment modified the expression of the transcription factor family C/EBPs (CCAAT/enhancer-binding proteins) but also of glycolysis related enzymes. Western blot and real time PCR confirmed an upregulation of C/EBP beta isoforms (LAP and LIP) with a more pronounced increase in the inhibitory isoform LIP. EMSA and reporter gene assays demonstrated the role of C/EBP beta isoforms in HSD11B2 gene expression regulation. In addition, secretion of lactate, a byproduct of glycolysis, was shown to mediate insulin-dependent HSD11B2 downregulation. In summary, we demonstrate that insulin downregulates HSD11B2 through increased LIP expression and augmented lactate secretion. Such mechanisms are of interest and potential significance for sodium reabsorption in the colon. PMID:25133511

  10. Lactate metabolism in the fetal rabbit lung

    SciTech Connect

    Engle, M.J.; Brown, D.J.; Dooley, M.

    1986-05-01

    Lactate is frequently overlooked as a potential substrate for the fetal lung, even though it is present in the fetal circulation in concentrations as high as 8 mM. These high concentrations, coupled with the relatively low levels of glucose in the fetal blood, may indicate that lactate can substitute for glucose in pulmonary energy generation and phospholipid synthesis. A series of experiments was therefore undertaken in order to investigate the role of lactate in perinatal pulmonary development. Explants from 30 day gestation fetal rabbit lungs were incubated in Krebs-Ringer bicarbonate buffer supplemented with 3 mM (U-/sup 14/C)-glucose and varying levels of lactate. In the absence of medium lactate, fetal rabbit lung explants were capable of producing lactate at a rate of approximately 200 etamoles/mg protein/hour. The addition of lactate to the bathing medium immediately reduced net lactate production and above 4 mM, fetal rabbit lung explants became net utilizers of lactate. Media lactate concentrations of 2.5 mM, 5 mM and 10 mM also decreased glucose incorporation into total tissue disaturated phosphatidylcholine by approximately 20%, 35%, and 45%, respectively. Glucose incorporation into surfactant phosphatidylcholine was also reduced by approximately 50%, when lactate was present in the incubation medium at a concentration of 5 mM. Additional experiments also revealed that fetal lung lactate dehydrogenase activity was almost twice that found in the adult rabbit lung. These data indicate that lactate may be an important carbon source for the developing lung and could be a significant component in the manufacture of surfactant phosphatidylcholine during late gestation.

  11. The intrinsically disordered protein LEA7 from Arabidopsis thaliana protects the isolated enzyme lactate dehydrogenase and enzymes in a soluble leaf proteome during freezing and drying.

    PubMed

    Popova, Antoaneta V; Rausch, Saskia; Hundertmark, Michaela; Gibon, Yves; Hincha, Dirk K

    2015-10-01

    The accumulation of Late Embryogenesis Abundant (LEA) proteins in plants is associated with tolerance against stresses such as freezing and desiccation. Two main functions have been attributed to LEA proteins: membrane stabilization and enzyme protection. We have hypothesized previously that LEA7 from Arabidopsis thaliana may stabilize membranes because it interacts with liposomes in the dry state. Here we show that LEA7, contrary to this expectation, did not stabilize liposomes during drying and rehydration. Instead, it partially preserved the activity of the enzyme lactate dehydrogenase (LDH) during drying and freezing. Fourier-transform infrared (FTIR) spectroscopy showed no evidence of aggregation of LDH in the dry or rehydrated state under conditions that lead to complete loss of activity. To approximate the complex influence of intracellular conditions on the protective effects of a LEA protein in a convenient in-vitro assay, we measured the activity of two Arabidopsis enzymes (glucose-6-P dehydrogenase and ADP-glucose pyrophosphorylase) in total soluble leaf protein extract (Arabidopsis soluble proteome, ASP) after drying and rehydration or freezing and thawing. LEA7 partially preserved the activity of both enzymes under these conditions, suggesting its role as an enzyme protectant in vivo. Further FTIR analyses indicated the partial reversibility of protein aggregation in the dry ASP during rehydration. Similarly, aggregation in the dry ASP was strongly reduced by LEA7. In addition, mixtures of LEA7 with sucrose or verbascose reduced aggregation more than the single additives, presumably through the effects of the protein on the H-bonding network of the sugar glasses. PMID:25988244

  12. A thioredoxin fusion protein of VanH, a D-lactate dehydrogenase from Enterococcus faecium: cloning, expression, purification, kinetic analysis, and crystallization.

    PubMed Central

    Stoll, V. S.; Manohar, A. V.; Gillon, W.; MacFarlane, E. L.; Hynes, R. C.; Pai, E. F.

    1998-01-01

    The gene encoding the vancomycin resistance protein VanH from Enterococcus faecium, a D-lactate dehydrogenase, has been cloned into a thioredoxin expression system (pTRxFus) and expressed as a fusion protein. The use of several other expression systems yielded only inclusion bodies from which no functional protein could be recovered. Experiments to remove the thioredoxin moiety by enterokinase cleavage at the engineered recognition site under a variety of conditions resulted in nonspecific proteolysis and inactivation of the protein. The intact fusion protein was, therefore, used for kinetic studies and crystallization trials. It has been purified to greater than 90% homogeneity by ammonium sulfate precipitation followed by phenyl Sepharose chromatography. Based on k(cat)/KM for pyruvate, it is 20% as active as native VanH. Michaelis constants for NADPH, NADH, and pyruvate, of approximately 3.5 microM, 19.0 microM, and 1.5 mM, respectively, were comparable to those reported for the native VanH (Bugg TDH et al., 1991, Biochemistry 30:10408-10415). Like native VanH, maximum activity of the fusion protein requires the presence of an anion (phosphate or acetate), however, in addition, a strongly reducing environment is needed for optimal efficacy. Competitive inhibition constants for ADP-ribose, NAD+, and oxamate have also been determined. Crystallization by hanging drop vapor diffusion produced two different crystal forms, one hexagonal and the other tetragonal. Flash-frozen crystals of the tetragonal form diffracted to 3.0 A resolution at a synchrotron radiation source. PMID:9605319

  13. Effects of corn-based diet starch content and corn particle size on lactation performance, digestibility, and bacterial protein flow in dairy cows.

    PubMed

    Fredin, S M; Ferraretto, L F; Akins, M S; Bertics, S J; Shaver, R D

    2015-01-01

    An experiment was conducted to determine the effects of dietary starch content in corn-based diets and corn particle size on lactation performance, nutrient digestibility, and bacterial protein flow in dairy cows using the omasal and reticular sampling technique. Eight ruminally cannulated lactating multiparous Holstein cows were used in a replicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Treatments were fine (FG; mean particle size=552µm) and coarse (CG; 1,270µm) ground dry shelled corn in normal- (NS) and reduced- (RS) starch diets fed as total mixed rations. The NS and RS rations contained 27 and 18% starch (dry matter basis), respectively, and were formulated by partially replacing corn with soy hull pellets. Mean dry matter intake was unaffected by treatment (23.2kg/d). Cows fed NS diets produced 1.9kg/d more milk and 0.06kg/d more milk protein compared with cows fed RS diets. Cows fed NSFG and RSCG diets produced more fat-corrected milk than did cows fed NSCG and RSFG diets. Milk urea concentration was decreased for cows fed NS diets (12.4mg/dL) compared with RS diets (13.5mg/dL). Ruminal digestibility of neutral detergent fiber (NDF; % of NDF intake) determined by the omasal sampling technique was increased in cows fed RS diets compared with NS diets (43.4 vs. 34.9%), and total-tract digestibility of NDF (% of NDF intake) was increased in cows fed RS diets compared with those fed NS diets (50.1 vs. 43.1%). Ruminal digestibility of starch (% of starch intake) determined by the omasal sampling technique was greater in cows fed NS diets compared with those fed RS diets (85.6 vs. 81.6%). Total-tract starch digestion was increased in cows fed RS diets compared with those fed NS diets (96.9 vs. 94.6%) and in cows fed FG diets compared with those fed CG diets (98.0 vs. 93.5%). Bacterial protein flow was unaffected by treatment. The omasal and reticular sampling techniques resulted in similar treatment effects for nutrient flow

  14. Parathyroid hormone-related protein is required for tooth eruption

    PubMed Central

    Philbrick, William M.; Dreyer, Barbara E.; Nakchbandi, Inaam A.; Karaplis, Andrew C.

    1998-01-01

    Parathyroid hormone (PTH)-related protein (PTHrP)-knockout mice die at birth with a chondrodystrophic phenotype characterized by premature chondrocyte differentiation and accelerated bone formation, whereas overexpression of PTHrP in the chondrocytes of transgenic mice produces a delay in chondrocyte maturation and endochondral ossification. Replacement of PTHrP expression in the chondrocytes of PTHrP-knockout mice using a procollagen II-driven transgene results in the correction of the lethal skeletal abnormalities and generates animals that are effectively PTHrP-null in all sites other than cartilage. These rescued PTHrP-knockout mice survive to at least 6 months of age but are small in stature and display a number of developmental defects, including cranial chondrodystrophy and a failure of tooth eruption. Teeth appear to develop normally but become trapped by the surrounding bone and undergo progressive impaction. Localization of PTHrP mRNA during normal tooth development by in situ hybridization reveals increasing levels of expression in the enamel epithelium before the formation of the eruption pathway. The type I PTH/PTHrP receptor is expressed in both the adjacent dental mesenchyme and in the alveolar bone. The replacement of PTHrP expression in the enamel epithelium with a keratin 14-driven transgene corrects the defect in bone resorption and restores the normal program of tooth eruption. PTHrP therefore represents an essential signal in the formation of the eruption pathway. PMID:9751753

  15. Evaluation of Markers of Bone Turnover During Lactation in African-Americans: A Comparison With Caucasian Lactation

    PubMed Central

    Carneiro, Raquel M.; Prebehalla, Linda; Tedesco, Mary Beth; Sereika, Susan M.; Gundberg, Caren M.; Stewart, Andrew F.

    2013-01-01

    Context: The African-American skeleton is resistant to PTH; whether it is also resistant to PTHrP and the hormonal milieu of lactation is unknown. Objectives: The objective of the study was to assess bone turnover markers in African-Americans during lactation vs Caucasians. Design and Participants: A prospective cohort study with repeated measures of markers of bone turnover in 60 African-American women (3 groups of 20: lactating, bottle feeding, and healthy controls), compared with historic Caucasian women. Setting: The study was conducted at a university medical center. Outcome Measures: Biochemical markers of bone turnover and calcium metabolism were measured. Results: 25-Hydroxyvitamin D (25-OHD) and PTH were similar among all 3 African-American groups, but 25-OHD was 30%–50% lower and PTH 2-fold higher compared with Caucasians (P < .001, P < .002), with similar 1,25 dihydroxyvitamin D [1,25(OH)2D] values. Formation markers [amino-terminal telopeptide of procollagen-1 (P1NP) and bone-specific alkaline phosphatase (BSAP)] increased significantly (2- to 3-fold) in lactating and bottle-feeding African-American women (P1NP, P < .001; BSAP, P < .001), as did resorption [carboxy-terminal telopeptide of collagen-1 (CTX) and serum amino-terminal telopeptide of collagen 1 (NTX), both P < .001]. P1NP and BSAP were comparable in African-American and Caucasian controls, but CTX and NTX were lower in African-American vs Caucasian controls. African-American lactating mothers displayed quantitatively similar increases in markers of bone formation but slightly lower increases in markers of resorption vs Caucasians (P = .036). Conclusions: Despite reported resistance to PTH, lactating African-American women have a significant increase in markers of bone resorption and formation in response the hormonal milieu of lactation. This response is similar to that reported in Caucasian women despite racial differences in 25-OHD and PTH. Whether this is associated with similar bone

  16. Inhibition of parathyroid hormone-related protein release by extracellular calcium in dispersed cells from human parathyroid hyperplasia secondary to chronic renal failure and adenoma.

    PubMed Central

    Matsushita, H.; Hara, M.; Honda, K.; Kuroda, M.; Usui, M.; Nakazawa, H.; Hara, S.; Shishiba, Y.

    1995-01-01

    The relationship between parathyroid hormone-related protein (PTHrP) release from parathyroid cells and extracellular calcium ion concentration was investigated in three cases of parathyroid hyperplasia secondary to chronic renal failure and in four cases of parathyroid adenoma. Amounts of PTHrP released from individual parathyroid cells dispersed from surgical specimens were estimated by cell immunoblot assay. Parathyroid cells from both hyperplasias and adenomas showed significant suppression in the release of PTHrP with increase in extracellular calcium ions, but the amounts of PTHrP released from adenoma cells were significantly larger than from hyperplasia cells. The maximal value for PTHrP released within 120 minutes from adenoma cells was 2.91 +/- 2.11 x 10(-2) fmol/cell ([Ca2+], 0.4 mmol/L), and the minimal value was 1.32 +/- 0.35 x 10(-2) fmol/cell ([Ca2+], 2.0 mmol/L). On the other hand, the maximal value for PTHrP released from hyperplasia cells was 1.79 +/- 1.56 x 10(-2) fmol/cell ([Ca2+], 0.4 mmol/L), and the minimal value was 0.32 +/- 0.19 x 10(-2) fmol/cell ([Ca2+], 2.0 mmol/L). These results demonstrate actual release of PTHrP from abnormal parathyroid tissues into the extracellular space with the response to extracellular calcium ions depending on the cell status. Given the lack of definite histological criteria to differentiate between hyperplasias and adenomas in the parathyroid gland, the presently demonstrated significant difference in the ability to release PTHrP is important in pointing to parathyroid hyperplasia secondary to chronic renal failure as a distinct pathological entity separate from parathyroid adenoma. Images Figure 3 PMID:7778690

  17. Effects of exposure to bisphenol A during pregnancy and lactation on the testicular morphology and caspase-3 protein expression of ICR pups

    PubMed Central

    LIU, XIAO-LI; CHEN, XIAO-YU; WANG, ZHI-CHENG; SHEN, TONG; ZHAO, HUNA

    2013-01-01

    Bisphenol A (BPA), a xenoestrogen and endocrine-disrupting chemical, is a cause for concern due to its being a potential human carcinogen. The aim of this study was to investigate the effects of continued maternal exposure to BPA on the testicular structures and expression of caspase-3 protein in male ICR offspring during pregnancy and lactation and explore its possible mechanism. Pregnant ICR mice were divided into two control groups, which were either given or not given the solvent dimethyl sulfoxide (DMSO) and three treatment groups, which were gavaged with water-soluble BPA dissolved in DMSO at three different concentrations from gestational day 0 to weaning on postnatal day (PND) 21. The number of mice pups and ratios of males to females were recorded. On PND 21, male offspring were sacrificed to measure their wet weights and testicular coefficients. Electron microscopy was used to observe testicular morphological changes, Hoechst 33258 staining to detect cell apoptosis and immunohistochemistry to measure caspase-3 expression. Although there was no significant difference between offspring of the control group and the treatment group in litter size and male-female ratio (P>0.05), the testicular viscera coefficient in the latter decreased (P<0.01). Specifically, compared with offspring of the control group, in addition to increased cell apoptosis, those of the treatment groups were found to have changes in mitochondrial and endoplasmic reticulum in their spermatogenous, Sertoli, Leydig and peritubular myoid cells, which were concomitant with an elevated expression of caspase-3 in the cytoplasm (P<0.01). In conclusion, exposure of pregnant mice to BPA during pregnancy and lactation has some toxic effects on the testes of male ICR offspring and these may originate from increased apoptosis. PMID:24648961

  18. Genetics Home Reference: lactate dehydrogenase deficiency

    MedlinePlus

    ... dehydrogenase-B pieces (subunits) of the lactate dehydrogenase enzyme. This enzyme is found throughout the body and is important ... cells. There are five different forms of this enzyme, each made up of four protein subunits. Various ...

  19. Short-term administration of rhGH increases markers of cellular proliferation but not milk protein gene expression in normal lactating women.

    PubMed

    Maningat, Patricia D; Sen, Partha; Rijnkels, Monique; Hadsell, Darryl L; Bray, Molly S; Haymond, Morey W

    2011-04-27

    Growth hormone is one of few pharmacologic agents known to augment milk production in humans. We hypothesized that recombinant human GH (rhGH) increases the expression of cell proliferation and milk protein synthesis genes. Sequential milk and blood samples collected over four days were obtained from five normal lactating women. Following 24 h of baseline milk and blood sampling, rhGH (0.1 mg/kg/day) was administered subcutaneously once daily for 3 days. Gene expression changes were determined by microarray studies utilizing milk fat globule RNA isolated from each milk sample. Following rhGH administration, DNA synthesis and cell cycle genes were induced, while no significant changes were observed in the expression of milk synthesis genes. Expression of glycolysis and citric acid cycle genes were increased by day 4 compared with day 1, while lipid synthesis genes displayed a circadian-like pattern. Cell cycle gene upregulation occurred after a lag of ∼2 days, likely explaining the failure to increase milk production after only 3 days of rhGH treatment. We conclude that rhGH induces expression of cellular proliferation and metabolism genes but does not induce milk protein gene expression, as potential mechanisms for increasing milk production and could account for the known effect of rhGH to increase milk production following 7-10 days. PMID:21205870

  20. Short-term administration of rhGH increases markers of cellular proliferation but not milk protein gene expression in normal lactating women

    PubMed Central

    Maningat, Patricia D.; Sen, Partha; Rijnkels, Monique; Hadsell, Darryl L.; Bray, Molly S.

    2011-01-01

    Growth hormone is one of few pharmacologic agents known to augment milk production in humans. We hypothesized that recombinant human GH (rhGH) increases the expression of cell proliferation and milk protein synthesis genes. Sequential milk and blood samples collected over four days were obtained from five normal lactating women. Following 24 h of baseline milk and blood sampling, rhGH (0.1 mg/kg/day) was administered subcutaneously once daily for 3 days. Gene expression changes were determined by microarray studies utilizing milk fat globule RNA isolated from each milk sample. Following rhGH administration, DNA synthesis and cell cycle genes were induced, while no significant changes were observed in the expression of milk synthesis genes. Expression of glycolysis and citric acid cycle genes were increased by day 4 compared with day 1, while lipid synthesis genes displayed a circadian-like pattern. Cell cycle gene upregulation occurred after a lag of ∼2 days, likely explaining the failure to increase milk production after only 3 days of rhGH treatment. We conclude that rhGH induces expression of cellular proliferation and metabolism genes but does not induce milk protein gene expression, as potential mechanisms for increasing milk production and could account for the known effect of rhGH to increase milk production following 7–10 days. PMID:21205870

  1. Dietary carbohydrate composition modifies the milk N efficiency in late lactation cows fed low crude protein diets.

    PubMed

    Cantalapiedra-Hijar, G; Peyraud, J L; Lemosquet, S; Molina-Alcaide, E; Boudra, H; Nozière, P; Ortigues-Marty, I

    2014-02-01

    Nitrogen emissions from dairy cows can be readily decreased by lowering the dietary CP concentration. The main objective of this work was to test whether the milk protein yield reduction associated with low N intakes could be partially compensated for by modifying the dietary carbohydrate composition (CHO). The effects of CHO on digestion, milk N efficiency (milk N/N intake; MNE) and animal performance were studied in four Jersey cows fed 100% or 80% of the recommended protein requirements using a 4×4 Latin square design. Four iso-energetic diets were formulated to two different CHO sources (starch diets with starch content of 34.3% and NDF at 32.5%, and fiber diets with starch content of 5.5% and NDF at 49.1%) and two CP levels (Low=12.0% and Normal=16.5%). The apparent digestible organic matter intake (DOMI) and the protein supply (protein digestible in the small intestine; PDIE) were similar between starch and fiber diets. As planned, microbial N flow (MNF) to the duodenum, estimated from the urinary purine derivatives (PD) excretion, was similar between Low and Normal CP diets. However, the MNF and the efficiency of microbial synthesis (g of microbial N/kg apparently DOMI) were higher for starch v. fiber diets. Milk and milk N fractions (CP, true protein, non-protein N (NPN)) yield were higher for starch compared with fiber diets and for Normal v. Low CP diets. Fecal N excretion was similar across dietary treatments. Despite a higher milk N ouput with starch v. fiber diets, the CHO modified neither the urinary N excretion nor the milk urea-N (MUN) concentration. The milk protein yield relative to both N and PDIE intakes was improved with starch compared with fiber diets. Concentrations of β-hydroxybutyrate, urea and Glu increased and those of glucose and Ala decreased in plasma of cows fed starch v. fiber diets. On the other hand, plasma concentration of albumin, urea, insulin and His increased in cows fed Normal compared with Low CP diets. This study showed

  2. At the crossroads: EGFR and PTHrP signaling in cancer-mediated diseases of bone

    PubMed Central

    Nickerson, Nicole; Riese, David J.; Hollenhorst, Peter C.; Lorch, Gwendolen; Foley, Anne M.

    2014-01-01

    The epidermal growth factor receptor is a well-established cancer therapeutic target due to its stimulation of proliferation, motility, and resistance to apoptosis. Recently, additional roles for the receptor have been identified in growth of metastases. Similar to development, metastatic spread requires signaling interactions between epithelial-derived tumor cells and mesenchymal derivatives of the microenvironment. This necessitates reactivation of developmental signaling molecules, including the hypercalcemia factor parathyroid hormone-related protein. This review covers the variations of epidermal growth factor receptor signaling in cancers that produce bone metastases, regulation of parathyroid hormone-related protein, and evidence that the two molecules drive cancer-mediated diseases of bone. PMID:22684584

  3. Structural Basis for Parathyroid Hormone-related Protein Binding to the Parathyroid Hormone Receptor and Design of Conformation-selective Peptides

    SciTech Connect

    Pioszak, Augen A.; Parker, Naomi R.; Gardella, Thomas J.; Xu, H. Eric

    2009-12-01

    Parathyroid hormone (PTH) and PTH-related protein (PTHrP) are two related peptides that control calcium/phosphate homeostasis and bone development, respectively, through activation of the PTH/PTHrP receptor (PTH1R), a class B G protein-coupled receptor. Both peptides hold clinical interest for their capacities to stimulate bone formation. PTH and PTHrP display different selectivity for two distinct PTH1R conformations, but how their binding to the receptor differs is unclear. The high resolution crystal structure of PTHrP bound to the extracellular domain (ECD) of PTH1R reveals that PTHrP binds as an amphipathic {alpha}-helix to the same hydrophobic groove in the ECD as occupied by PTH, but in contrast to a straight, continuous PTH helix, the PTHrP helix is gently curved and C-terminally 'unwound.' The receptor accommodates the altered binding modes by shifting the side chain conformations of two residues within the binding groove: Leu-41 and Ile-115, the former acting as a rotamer toggle switch to accommodate PTH/PTHrP sequence divergence, and the latter adapting to the PTHrP curvature. Binding studies performed with PTH/PTHrP hybrid ligands having reciprocal exchanges of residues involved in different contacts confirmed functional consequences for the altered interactions and enabled the design of altered PTH and PTHrP peptides that adopt the ECD-binding mode of the opposite peptide. Hybrid peptides that bound the ECD poorly were selective for the G protein-coupled PTH1R conformation. These results establish a molecular model for better understanding of how two biologically distinct ligands can act through a single receptor and provide a template for designing better PTH/PTHrP therapeutics.

  4. Lactate Stimulates IL-4 and IL-13 Production in Activated HuT-78 T Lymphocytes Through a Process That Involves Monocarboxylate Transporters and Protein Hyperacetylation.

    PubMed

    Wagner, Waldemar; Ciszewski, Wojciech; Kania, Katarzyna; Dastych, Jarosław

    2016-05-01

    Mucosal cells of the gastrointestinal and female reproductive tract are constantly exposed to l- and d-lactate of bacterial origin. These compounds not only protect the host from pathogen colonization but also modulate the activity of mucosal immune cells, thereby playing an important role in inflammatory host responses. In this study, we demonstrated that exposure of anti-CD3/CD28 or phorbol 12-myristate 13-acetate (PMA)/ionomycin-activated HuT-78 T lymphocyte cells to 10-20 mM d-lactate significantly increased IL-4 and IL-13 production. Interestingly, the d-lactate isomer, exclusively produced locally by gut or cervicovaginal microbiota, was found to be more potent than the l-isomer. Interestingly, neither of the strong histone deacetylase inhibitors [structurally similar butyrate and suberoylanilide hydroxamic acid (SAHA)] was as effective in the stimulation of IL-13 production as d-lactate. Lactate transport through monocarboxylate transporters was required for lactate-enhanced IL-13 production in a manner that was not hydroxycarboxylic acid receptor 1-dependent. Furthermore, lactate treatment increased the acetylation of GATA-3, a critical regulator of Th1/Th2 differentiation and resulted in H3 and H4 histone hyperacetylation state, which is a characteristic feature of transcriptionally active chromatin. Both lactate isomers also enhanced IL4 and IL13 promoter-driven activity of reporter constructs in murine and human cells. Together, these findings demonstrate that a local millimolar concentration of l- or d-lactate may play an important role in the modulation of inflammation-mediated processes. PMID:27119568

  5. Molecular characterization of CcpA and involvement of this protein in transcriptional regulation of lactate dehydrogenase and pyruvate formate-lyase in the ruminal bacterium Streptococcus bovis.

    PubMed

    Asanuma, Narito; Yoshii, Takahiro; Hino, Tsuneo

    2004-09-01

    A ccpA gene that encodes global catabolite control protein A (CcpA) in Streptococcus bovis was identified and characterized, and the involvement of CcpA in transcriptional control of a gene (ldh) encoding lactate dehydrogenase (LDH) and a gene (pfl) encoding pyruvate formate-lyase (PFL) was examined. The ccpA gene was shown to be transcribed as a monocistronic operon. A catabolite-responsive element (cre) was found in the promoter region of ccpA, suggesting that ccpA transcription in S. bovis is autogenously regulated. CcpA required HPr that was phosphorylated at the serine residue at position 46 (HPr-[Ser-P]) for binding to the cre site, but glucose 6-phosphate, fructose 1,6-bisphosphate, and NADP had no effect on binding. Diauxic growth was observed when S. bovis was grown in a medium containing glucose and lactose, but it disappeared when ccpA was disrupted, which indicates that CcpA is involved in catabolite repression in S. bovis. The level of ccpA mRNA was higher when cells were grown on glucose than when they were grown on lactose, which was in line with the level of ldh mRNA. When cells were grown on glucose, the ldh mRNA level was lower but the pfl mRNA level was higher in a ccpA-disrupted mutant than in the parent strain, which suggests that ldh transcription is enhanced and pfl transcription is suppressed by CcpA. The ccpA-disrupted mutant produced less lactate and more formate than the parent, probably because the mutant had reduced LDH activity and elevated PFL activity. In the upper region of both ldh and pfl, a cre-like sequence was found, suggesting that the complex consisting of CcpA and HPr-[Ser-P] binds to the possible cre sites. Thus, CcpA appears to be involved in the global regulation of sugar utilization in S. bovis. PMID:15345406

  6. Lactation and reproduction*

    PubMed Central

    Thomson, A. M.; Hytten, F. E.; Black, A. E.

    1975-01-01

    The authors review the literature on the effect of lactation on fertility in the absence of contraception and on the effects of contraceptive measures on lactation. They examine data from several countries on the intervals between births and on the return of menstruation and ovulation after childbirth, comparing lactating with nonlactating women. They conclude that lactation is an inefficient contraceptive for the individual, but that in populations sustained lactation is associated with reduced fertility. Possible physiological mechanisms causing lactation amenorrhoea are discussed. Though much of the literature on the effect of contraceptives on lactation is inadequate, there is general agreement that the estrogen component of hormonal preparations has an adverse effect on lactation, but that progestins alone do not. Many questions remain. Is this effect seen in established lactation, or only in the puerperal period? Is it a direct pharmacological effect, or are pill-users the mothers least motivated to maintain breast-feeding? Does a close relationship exist between hormones given and lactation performance? The authors comment on some of the technical deficiencies of previous studies in this field and discuss practical possibilities of, and limitations to, obtaining adequate scientific information in the future. PMID:1084804

  7. Parathyroid Hormone-Related Protein, Its Regulation of Cartilage and Bone Development, and Role in Treating Bone Diseases.

    PubMed

    Martin, T John

    2016-07-01

    Although parathyroid hormone-related protein (PTHrP) was discovered as a cancer-derived hormone, it has been revealed as an important paracrine/autocrine regulator in many tissues, where its effects are context dependent. Thus its location and action in the vasculature explained decades-long observations that injection of PTH into animals rapidly lowered blood pressure by producing vasodilatation. Its roles have been specified in development and maturity in cartilage and bone as a crucial regulator of endochondral bone formation and bone remodeling, respectively. Although it shares actions with parathyroid hormone (PTH) through the use of their common receptor, PTHR1, PTHrP has other actions mediated by regions within the molecule beyond the amino-terminal sequence that resembles PTH, including the ability to promote placental transfer of calcium from mother to fetus. A striking feature of the physiology of PTHrP is that it possesses structural features that equip it to be transported in and out of the nucleus, and makes use of a specific nuclear import mechanism to do so. Evidence from mouse genetic experiments shows that PTHrP generated locally in bone is essential for normal bone remodeling. Whereas the main physiological function of PTH is the hormonal regulation of calcium metabolism, locally generated PTHrP is the important physiological mediator of bone remodeling postnatally. Thus the use of intermittent injection of PTH as an anabolic therapy for bone appears to be a pharmacological application of the physiological function of PTHrP. There is much current interest in the possibility of developing PTHrP analogs that might enhance the therapeutic anabolic effects. PMID:27142453

  8. Analysis of production responses to changing crude protein levels in lactating dairy cow diets when evaluated in continuous or change-over experimental designs.

    PubMed

    Zanton, G I

    2016-06-01

    The objective of this study was to evaluate by meta-analysis the effect of experimental design on the production response functions obtained when changing crude protein (CP) levels in lactating dairy cow diets. The final database of studies meeting the selection criteria contained 55 publications with 23 classified as using a continuous (80 diets) and 34 classified as using a change-over (173 diets) experimental design (2 publications reported results from trials using both designs). Mixed model, weighted analysis of covariance was conducted on production measures in response to CP including the continuous covariates year of publication and average days in milk (DIM) and the discrete classification covariate of experimental design. The model was evaluated for curvilinearity in the response to CP, variance heterogeneity, and coincidence in the response between experimental designs, with P<0.05 indicating significant effects and P<0.15 indicating trends. On average, cows in experiments using continuous designs had a lower initial DIM, were on treatment longer, and produced a greater yield of milk and milk protein than cows in experiments using change-over designs. Production responses to increasing CP were increased dry matter intake (DMI), milk and component yield, and feed efficiency (milk Mcal/kg of DMI), and decreased milk N:intake N. Response in milk yield and feed efficiency to increased CP interacted with experimental design where continuous experiments had greater milk yield and feed efficiency response at higher levels of CP. Interaction between CP and design effects on yield of milk protein and fat or milk N:intake N did not approach significance. The database is limited by the lower number of continuous studies and the differences in average DIM between designs; nevertheless, it is concluded that DMI, milk protein yield, milk fat yield, and milk N:intake N responses to CP did not depend on experimental design. Response of milk yield and feed efficiency to

  9. The effect of dietary energy source during mid to late lactation on liver triglyceride and lactation performance of dairy cows.

    PubMed

    Vazquez-Añon, M; Bertics, S J; Grummer, R R

    1997-10-01

    Control [1.61 Mcal of net energy for lactation (NEL)/kg of dry matter (DM)], high grain (1.70 Mcal of NEL)/kg of DM), or high fat [1.70 Mcal of NEL/kg of DM with 2.3% tallow (DM basis)] diets were fed to 43 cows (150 +/- 3.1 d in milk) during mid to late lactation to determine effects on performance characteristics, metabolic parameters, or both during mid to late lactation, the dry period, and the first 100 d of the next lactation. All cows received identical diets during the dry period and during early lactation. Increasing the energy density of the diets during mid to late lactation increased DM intake (DMI), plasma nonesterified fatty acid concentration, milk production, and milk protein yield. Compared with the high grain diets, fat supplementation decreased DMI and the percentage of milk protein but increased plasma nonesterified fatty acid concentration without causing elevation of liver triglyceride at the end of mid to late lactation. Increased energy density of the diets did not affect body condition score during mid to late lactation. There were no residual effects for any of the treatments on DMI, lactation performance, or body weight in the subsequent lactation. However, energy supplementation during mid to late lactation increased liver triglyceride content after calving. Compared with high fat diets, high grain diets fed during mid to late lactation increased plasma beta-hydroxy-butyrate concentration in the subsequent lactation. High energy diets fed during mid to late lactation may influence lipid metabolism during the following lactation. PMID:9361222

  10. Variation of transferrin mRNA concentration in the rabbit mammary gland during the pregnancy-lactation-weaning cycle and in cultured mammary cells. A comparison with the other major milk protein mRNAs.

    PubMed

    Puissant, C; Bayat-Sarmadi, M; Devinoy, E; Houdebine, L M

    1994-05-01

    The concentration of transferrin mRNA was evaluated during pregnancy and lactation in rabbit mammary gland and liver using northern blot and dot blot assays. Transferrin mRNA was present in the virgin rabbit mammary gland and its concentration increased as pregnancy proceeded, with a major enhancement after day 15. A high concentration was reached 3 days after parturition, with no additional increase during lactation and with a marked decline after weaning. During the same period, the concentration of transferrin mRNA showed only a very weak variation in liver. This mRNA was six times more abundant in mammary gland than in liver of lactating rabbit. The accumulation of transferrin mRNA in the mammary gland was concomitant with the accumulation of alpha s1-, beta-, kappa-casein and WAP (whey acidic protein) mRNAs. The concentration of glyceraldehyde 3-phosphate dehydrogenase mRNA, taken as a non-inducible control mRNA, declined progressively during pregnancy to reach its lower level in lactation. These observations suggest that casein, WAP and transferrin mRNAs are subjected to a similar control mechanism in vivo, at least in the second half of pregnancy and during lactation. Experiments carried out in vitro using isolated rabbit epithelial mammary cells cultured on collagen I gel indicated that transferrin mRNA was abundant and only weakly inducible by the lactogenic hormones insulin, cortisol and prolactin, as opposed to caseins and WAP mRNAs. R5020, an analogue of progesterone, inhibited at most very slightly the accumulation of alpha s1-casein mRNA in the presence of prolactin and it did not reduce the expression of transferrin gene.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8180682

  11. Crystallization of the receptor-binding domain of parathyroid hormone-related protein in complex with a neutralizing monoclonal antibody Fab fragment

    SciTech Connect

    McKinstry, William J.; Polekhina, Galina; Diefenbach-Jagger, Hannelore; Sato, Koh; Onuma, Etsuro; Gillespie, Matthew T.; Martin, Thomas J.; Parker, Michael W.

    2009-04-01

    Parathyroid hormone-related protein (PTHrP) plays an important role in regulating embryonic skeletal development and is abnormally regulated in the pathogenesis of skeletal complications observed with many cancers and osteoporosis. It exerts its action through binding to a G-protein-coupled seven-transmembrane cell-surface receptor (GPCR). Structurally, GPCRs are very difficult to study by X-ray crystallography. In this study, a monoclonal antibody Fab fragment which recognizes the same region of PTHrP as its receptor, PTH1R, was used to aid in the crystallization of PTHrP. The resultant protein complex was crystallized using the hanging-drop vapour-diffusion method with polyethylene glycol as a precipitant. The crystals belonged to the orthorhombic space group P2{sub 1}2{sub 1}2, with unit-cell parameters a = 72.6, b = 96.3, c = 88.5 {angstrom}, and diffracted to 2.0 {angstrom} resolution using synchrotron radiation. The crystal structure will shed light on the nature of the key residues of PTHrP that interact with the antibody and will provide insights into how the antibody is able to discriminate between PTHrP and the related molecule parathyroid homone.

  12. Extended lactation in dairy cows: effects of milking frequency, calving season and nutrition on lactation persistency and milk quality.

    PubMed

    Sorensen, Annette; Muir, D Donald; Knight, Christopher H

    2008-02-01

    Twelve spring-calving and twelve winter-calving cows were managed for extended lactation cycles of 18-months duration, with the former group then completing a second extended lactation. Half of the cows were fed according to standard management practice for the herd; the other half received supplementary concentrate from week 9 of lactation onwards. Commencing at the same time, half of the udder of each cow was subjected to increased milking frequency (thrice daily rather than twice daily). Lactation persistency (and hence total milk yield) was significantly increased by frequent milking. Winter calving cows and supplemented cows also exhibited better persistency, but this was only evident up until the point of re-breeding, at around lactation week 33. Milk composition was measured in the spring-calving cows in both their first and second extended lactations. Composition altered during the course of the lactation, protein and fat percentages increasing and lactose percentage decreasing, irrespective of treatment. The quality of the milk for processing into cheese, fermented products, heat-treated products and cream liqueurs was assessed by calculation of casein number (casein protein as a proportion of total protein). Processing quality declined across the course of lactation in those groups that showed poor persistency but not in those that maintained a persistent lactation. Milk hygienic quality (somatic cell counts) showed parallel changes. Body condition score increased during the course of lactation but was not affected by supplementation; none of the cows became excessively fat. All cows remained healthy throughout the extended lactations and the majority (33/36) re-bred successfully. By demonstrating that lactation persistency is plastic and can be improved by simple management interventions, the results lend support to the economic arguments in favour of extended lactation cycles. The likely welfare benefits of extended lactation are also discussed. PMID

  13. Current trends in lactate metabolism: introduction.

    PubMed

    Gladden, L Bruce

    2008-03-01

    In September 2006, at the Integrative Physiology of Exercise meeting in Indianapolis, IN, a symposium entitled "Current Trends in Lactate Metabolism" was presented. This short paper introduces two papers from that symposium. The first paper by L. Bruce Gladden briefly summarizes key pieces of evidence that support the cell-to-cell lactate shuttle, a concept that is no longer an hypothesis but that, instead, is now an established theory that provides the context for discussions of whole body metabolism. Gladden also offers a critical appraisal of the intracellular lactate shuttle and evaluates an ongoing controversy relative to the role of lactate in acid-base balance. In the second paper, Hashimoto and Brooks provide their evidence in support of the intracellular lactate shuttle and a lactate oxidation complex in the inner mitochondrial membrane. They also postulate that lactate is a cell-signaling molecule, "lactormone," that can upregulate gene and protein expression. Both papers have been updated since their original presentations and represent the current state of knowledge. PMID:18379209

  14. Physiology of lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The breast changes in size, shape, and function during puberty, pregnancy, and lactation. The physiology of lactation is reviewed here. The breast is composed of fat and connective tissue that supports a tubuloalveolar structure. During development, anatomic changes involving new lobule formation an...

  15. Effect of replacing soybean meal protein with protein from upland cottonseed, Pima cottonseed, or extruded Pima cottonseed on production of lactating dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pima cotton production is increasing in the U.S., but Pima cottonseed contains higher concentrations of the toxic pigment gossypol than conventional upland cottonseed. Heating promotes gossypol reaction with protein, reducing gossypol absorption and toxicity. The objective of this study was to asses...

  16. Effect of dietary protein level and rumen-protected amino acid supplementation on amino acid utilization for milk protein in lactating dairy cows.

    PubMed

    Lee, C; Giallongo, F; Hristov, A N; Lapierre, H; Cassidy, T W; Heyler, K S; Varga, G A; Parys, C

    2015-03-01

    This study investigated the effect of metabolizable protein (MP) supply and rumen-protected (RP) Lys and Met supplementation on productivity, nutrient digestibility, urinary N losses, apparent total-tract digestibility of dietary AA, and the efficiency of AA utilization for milk protein synthesis in dairy cows. The experiment was conducted with 8 ruminally cannulated Holstein cows in a replicated 4×4 Latin square design trial with 21-d periods. Treatments were (1) MP-adequate diet (AMP; MP balance of -24 g/d); (2) MP-deficient diet (DMP; MP balance of -281 g/d); (3) DMP supplemented with 100 g of RPLys/cow per day (estimated digestible Lys supply=24 g/d; DMPL; MP balance of -305g/d); and (4) DMPL supplemented with 24 g of RPMet/cow per day (estimated digestible Met supply=15 g/d; DMPLM; MP balance of -256g/d). Diet had no effect on total-tract nutrient digestibility, milk production, and milk composition, but the DMP diets decreased urinary N excretion and the ammonia emitting potential of manure. Plasma Met concentration was increased by DMPLM compared with AMP. Supplementation with RPLys had no effect on plasma Lys. Concentration of most AA in milk protein was increased or tended to be increased by DMPLM compared with DMPL. Except for the AA supplemented as RPAA (i.e., Met and Lys), apparent total-tract digestibility of all dietary AA was generally greater for the DMP diets and ranged from 33% (Arg, AMP diet) to 67% (Thr, DMPL diet). Apparent recovery of dietary AA in milk protein followed the same trends, being greater for the DMP diets than AMP and generally lower for Lys and Met with the RPAA-supplemented diets versus AMP and DMP. The RPAA were apparently not used for milk protein synthesis in the conditions of this experiment. The AA recoveries in milk protein varied from around 17% (Ala) to 70% (Pro). Milk protein recoveries of essential AA (EAA) were around 54% for the DMP diet and 49% for AMP. The estimated efficiency of utilization of digestible EAA for

  17. EFFECTS OF FEEDING FORMATE-TREATED ALFALFA SILAGE OR RED CLOVER SILAGE ON OMASAL FLOW OF NUTRIENTS AND MICROBIAL PROTEIN SYNTHESIS IN LACTATING DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eight ruminally cannulated Holstein cows that were part of a larger lactation trial were blocked by days in milk and randomly assigned to replicated 4 x 4 Latin squares to quantify effects of nonprotein N (NPN) content of alfalfa silage (AS) and red clover silage (RCS) on omasal nutrient flows. Diet...

  18. Mitochondrial Respiratory Defect Causes Dysfunctional Lactate Turnover via AMP-activated Protein Kinase Activation in Human-induced Pluripotent Stem Cell-derived Hepatocytes.

    PubMed

    Im, Ilkyun; Jang, Mi-Jin; Park, Seung Ju; Lee, Sang-Hee; Choi, Jin-Ho; Yoo, Han-Wook; Kim, Seyun; Han, Yong-Mahn

    2015-12-01

    A defective mitochondrial respiratory chain complex (DMRC) causes various metabolic disorders in humans. However, the pathophysiology of DMRC in the liver remains unclear. To understand DMRC pathophysiology in vitro, DMRC-induced pluripotent stem cells were generated from dermal fibroblasts of a DMRC patient who had a homoplasmic mutation (m.3398T→C) in the mitochondrion-encoded NADH dehydrogenase 1 (MTND1) gene and that differentiated into hepatocytes (DMRC hepatocytes) in vitro. DMRC hepatocytes showed abnormalities in mitochondrial characteristics, the NAD(+)/NADH ratio, the glycogen storage level, the lactate turnover rate, and AMPK activity. Intriguingly, low glycogen storage and transcription of lactate turnover-related genes in DMRC hepatocytes were recovered by inhibition of AMPK activity. Thus, AMPK activation led to metabolic changes in terms of glycogen storage and lactate turnover in DMRC hepatocytes. These data demonstrate for the first time that energy depletion may lead to lactic acidosis in the DMRC patient by reduction of lactate uptake via AMPK in liver. PMID:26491018

  19. Short communication: Supplementing lysine and methionine in a lactation diet containing a high concentration of wet corn gluten feed did not alter milk protein yield.

    PubMed

    Mullins, C R; Weber, D; Block, E; Smith, J F; Brouk, M J; Bradford, B J

    2013-08-01

    Primiparous (n=33) and multiparous (n=63) lactating Holstein cows (186±51 d in milk) were used to evaluate the effects of supplementing metabolizable amino acids using lysine in a matrix of Ca salts of fatty acids (Megamine-L, Arm & Hammer Animal Nutrition, Princeton, NJ) and the isopropyl ester of 2-hydroxy-4-(methylthio) butanoic acid (MetaSmart, Adisseo Inc., Antony, France) in diets containing >26% wet corn gluten feed (dry matter basis). Cows were blocked by production level, parity, and pregnancy status, then randomly assigned to 1 of 8 pens and allowed a 7-d adaption period before receiving dietary treatments for 28 d. Pens were assigned randomly to either of 2 diets formulated to differ by metabolizable amino acid supply. Dry matter intake and production were monitored daily and milk components analyzed 3d/wk. Data were analyzed using mixed models with repeated measures. The original design of the study consisted of a control diet predicted to be deficient in lysine and methionine; however, after ingredient nutrients were analyzed and modeled with animal requirements at dry matter intake [26.6±0.35 kg/d (mean ± SEM)] and milk production levels achieved during the study (40.1±0.46 kg/d), only marginal deficiencies were predicted for the control (-8.1g/d for lysine; -1g/d for methionine) according to the National Research Council method, whereas the Cornell Net Carbohydrate and Protein System 5.0 and 6.1 models indicated positive balances for these amino acids (25.9 and 21.8 g/d for lysine, 14.7 and 18.9 g/d for methionine, respectively). Supplementing 30 g/d of metabolizable lysine in a Ca soap matrix and 2.4 g/d of metabolizable methionine as 2-hydroxy-4-(methylthio) butanoic acid led to positive predicted lysine and methionine balances by all 3 models, and predicted metabolizable lysine-to-methionine ratios ranging from 2.9 to 3.1. No treatment effects were observed for dry matter intake, milk yield, milk component concentrations or yields, or energy

  20. Lactational exposure of phthalate causes long-term disruption in testicular architecture by altering tight junctional and apoptotic protein expression in Sertoli cells of first filial generation pubertal Wistar rats.

    PubMed

    Sekaran, S; Balaganapathy, P; Parsanathan, R; Elangovan, S; Gunashekar, J; Bhat, F A; Jagadeesan, A

    2015-06-01

    Di(2-ethylhexyl) phthalate (DEHP) is a ubiquitous environmental contaminant and a well-known endocrine disruptor (ED) that interferes with the reproductive function in both humans and animals. This study aimed to find out the impact of lactational exposure of DEHP in testes of first filial generation (F1) progeny male rat postnatal day (PND)-60. Lactating dams were orally treated with DEHP (0, 1, 10 and 100 mg/kg body weight/day, respectively) from the PND-1 to PND-21. Rats were killed at PND 60. Testes were removed and used for histological analysis and for isolation of Sertoli cells (SCs). The histoarchitecture of DEHP-treated rats showed disturbed testicular structure. DEHP-treated rats also showed increased oxidative stress by decreasing antioxidant levels in the SCs; it disrupted SC tight junctional proteins occludin, claudin, junctional adhesion molecule, zona occludens protein-1 (ZO-1), zona occludens protein-2 (ZO-2), and afadin-6 (AF-6), increased apoptosis by altering the apoptotic genes Bax, cytochrome c, caspase-8, -9, -3 and antiapoptotic gene Bcl-2. It is concluded that early postnatal exposure to DEHP disturbs histoarchitecture of testis and SC function in pubertal Wistar rats. PMID:25352649

  1. Parathyroid hormone-related protein secretion is inhibited by oestradiol and stimulated by antioestrogens in KPL-3C human breast cancer cells.

    PubMed Central

    Kurebayashi, J.; Sonoo, H.

    1997-01-01

    We recently established a human breast cancer cell line, KPL-3C, from a breast cancer patient with humoral hypercalcaemia. This cell line possesses oestrogen receptor (ER) and secretes parathyroid hormone-related protein (PTHrP) into medium. To investigate the effects of oestrogen and antioestrogens on PTHrP secretion, KPL-3C cells were cultured for 48 h in an oestrogen-eliminated medium with 17beta-oestradiol (E2), tamoxifen (TAM) and/or a pure antioestrogen, ICI182,780 (ICI), and PTHrP secretion was measured using an immunoradiometric assay. The effects of these agents on cell cycle progression were also studied using flow cytometry. E2 (1-100 nM) significantly inhibited PTHrP secretion, whereas both TAM (0.1-10 microM) and ICI (1-100 nM) significantly stimulated it. These effects were completely blocked by the simultaneous addition of 1 nM E2 to the medium. At the same time, E2 significantly increased the percentage of cells during the S and G2/M phases, whereas both antioestrogens significantly increased the percentage of cells during the G0/G1 phase. Again, these cytostatic effects were completely reversed by the addition of E2. These findings indicate that antioestrogens inhibit the growth of ER-positive breast cancer cells but may stimulate PTHrP secretion and that these effects may be mediated by ER. PMID:9192988

  2. [Psychopharmacotherapy in pregnancy and lactation. 2: Lactation].

    PubMed

    Lanczik, M; Knoche, M; Fritze, J

    1998-01-01

    Whilst the incidence of psychiatric disorders decreases during pregnancy, the risk during the postpartum period increases significantly, often leading to the necessity of psychopharmacological intervention during the puerperium, and subsequently during lactation and breast-feeding. The necessity for lithium prophylaxis in manic-depressive women after childbirth has been identified, and it is recommended that weaning rather than omission of psychopharmacological treatment is preferable during the puerperium. PMID:9522328

  3. Treatment with N- and C-Terminal Peptides of Parathyroid Hormone-Related Protein Partly Compensate the Skeletal Abnormalities in IGF-I Deficient Mice

    PubMed Central

    Portal-Núñez, Sergio; Murillo-Cuesta, Silvia; Lozano, Daniel; Cediel, Rafael; Esbrit, Pedro

    2014-01-01

    Insulin-like growth factor-I (IGF-I) deficiency causes growth delay, and IGF-I has been shown to partially mediate bone anabolism by parathyroid hormone (PTH). PTH-related protein (PTHrP) is abundant in bone, and has osteogenic features by poorly defined mechanisms. We here examined the capacity of PTHrP (1–36) and PTHrP (107–111) (osteostatin) to reverse the skeletal alterations associated with IGF-I deficiency. Igf1-null mice and their wild type littermates were treated with each PTHrP peptide (80 µg/Kg/every other day/2 weeks; 2 males and 4 females for each genotype) or saline vehicle (3 males and 3 females for each genotype). We found that treatment with either PTHrP peptide ameliorated trabecular structure in the femur in both genotypes. However, these peptides were ineffective in normalizing the altered cortical structure at this bone site in Igf1-null mice. An aberrant gene expression of factors associated with osteoblast differentiation and function, namely runx2, osteoprotegerin/receptor activator of NF-κB ligand ratio, Wnt3a, cyclin D1, connexin 43, catalase and Gadd45, as well as in osteocyte sclerostin, was found in the long bones of Igf1-null mice. These mice also displayed a lower amount of trabecular osteoblasts and osteoclasts in the tibial metaphysis than those in wild type mice. These alterations in Igf1-null mice were only partially corrected by each PTHrP peptide treatment. The skeletal expression of Igf2, Igf1 receptor and Irs2 was increased in Igf1-null mice, and this compensatory profile was further improved by treatment with each PTHrP peptide related to ERK1/2 and FoxM1 activation. In vitro, PTHrP (1–36) and osteostatin were effective in promoting bone marrow stromal cell mineralization in normal mice but not in IGF-I-deficient mice. Collectively, these findings indicate that PTHrP (1–36) and osteostatin can exert several osteogenic actions even in the absence of IGF-I in the mouse bone. PMID:24503961

  4. PTH-related protein upregulates integrin {alpha}6{beta}4 expression and activates Akt in breast cancer cells

    SciTech Connect

    Shen Xiaoli; Falzon, Miriam . E-mail: mfalzon@utmb.edu

    2006-11-15

    Breast cancer is the most common carcinoma that metastasizes to bone. Tumor-produced parathyroid hormone-related protein (PTHrP), a known stimulator of osteoclastic bone resorption, is a major mediator of the osteolytic process in breast cancer. We have previously shown that PTHrP increases breast cancer cell proliferation, survival, migration, and pro-invasive integrin {alpha}6{beta}4 expression. To determine the role of integrin {alpha}6{beta}4 in these PTHrP-mediated effects, we utilized two strategies to modulate expression of the {alpha}6 and {beta}4 subunits in parental and PTHrP-overexpressing MDA-MB-231 and MCF-7 cells: overexpression of {alpha}6{beta}4 by transfection with constructs encoding the {alpha}6 and {beta}4 subunits, and suppression of endogenous {alpha}6{beta}4 expression by transfection with siRNAs targeting these subunits. We now show that the effects of PTHrP are mediated via upregulation of integrin {alpha}6{beta}4 expression. We also show that integrin {alpha}6{beta}4 expression is modulated at the mRNA level, indicating a transcriptional and/or post-transcriptional mechanism of action for PTHrP. PTHrP expression also increased the levels of phosphorylated Akt, with a consequent increase in the levels of phosphorylated (inactive) glycogen synthase kinase-3 (GSK-3). The role of PTHrP in breast cancer growth and metastasis may thus be mediated via upregulation of integrin {alpha}6{beta}4 expression and Akt activation, with consequent inactivation of GSK-3.

  5. Lactate: Friend or Foe.

    PubMed

    Hall, Mederic M; Rajasekaran, Sathish; Thomsen, Timothy W; Peterson, Andrew R

    2016-03-01

    Lactic acid has played an important role in the traditional theory of muscle fatigue and limitation of endurance exercise performance. It has been called a waste product of anaerobic metabolism and has been believed to be responsible for the uncomfortable "burn" of intense exercise and directly responsible for the metabolic acidosis of exercise, leading to decreased muscle contractility and ultimately cessation of exercise. Although this premise has been commonly taught, it is not supported by the scientific literature and has led to a great deal of confusion among the sports medicine and exercise science communities. This review will provide the sports medicine clinician with an understanding of contemporary lactate theories, including lactate's role in energy production, its contributions to metabolic acidosis, and its function as an energy substrate for a variety of tissues. Lactate threshold concepts will also be discussed, including a practical approach to understanding prediction of performance and monitoring of training progress based on these parameters. PMID:26972271

  6. Calcium mobilization from fish scales is mediated by parathyroid hormone related protein via the parathyroid hormone type 1 receptor.

    PubMed

    Rotllant, J; Redruello, B; Guerreiro, P M; Fernandes, H; Canario, A V M; Power, D M

    2005-12-15

    The scales of bony fish represent a significant reservoir of calcium but little is known about their contribution, as well as of bone, to calcium balance and how calcium deposition and mobilization are regulated in calcified tissues. In the present study we report the action of parathyroid hormone-related protein (PTHrP) on calcium mobilization from sea bream (Sparus auratus) scales in an in vitro bioassay. Ligand binding studies of piscine 125I-(1-35(tyr))PTHrP to the membrane fraction of isolated sea bream scales revealed the existence of a single PTH receptor (PTHR) type. RT-PCR of fish scale cDNA using specific primers for two receptor types found in teleosts, PTH1R, and PTH3R, showed expression only of PTH1R. The signalling mechanisms mediating binding of the N-terminal amino acid region of PTHrP were investigated. A synthetic peptide (10(-8) M) based on the N-terminal 1-34 amino acid residues of Fugu rubripes PTHrP strongly stimulated cAMP synthesis and [3H]myo-inositol incorporation in sea bream scales. However, peptides (10(-8) M) with N-terminal deletions, such as (2-34), (3-34) and (7-34)PTHrP, were defective in stimulating cAMP production but stimulated [3H]myo-inositol incorporation. (1-34)PTHrP induced significant osteoclastic activity in scale tissue as indicated by its stimulation of tartrate-resistant acid phosphatase. In contrast, (7-34)PTHrP failed to stimulate the activity of this enzyme. This activity could also be abolished by the adenylyl cyclase inhibitor SQ-22536, but not by the phospholipase C inhibitor U-73122. The results of the study indicate that one mechanism through which N-terminal (1-34)PTHrP stimulates osteoclastic activity of sea bream scales, is through PTH1R and via the cAMP/AC intracellular signalling pathway. It appears, therefore, that fish scales can act as calcium stores and that (1-34)PTHrP regulates calcium mobilization from them; it remains to be established if this mechanism contributes to calcium homeostasis in vivo

  7. Local delivery of parathyroid hormone-related protein-derived peptides coated onto a hydroxyapatite-based implant enhances bone regeneration in old and diabetic rats.

    PubMed

    Ardura, Juan A; Portal-Núñez, Sergio; Lozano, Daniel; Gutiérrez-Rojas, Irene; Sánchez-Salcedo, Sandra; López-Herradón, Ana; Mulero, Francisca; Villanueva-Peñacarrillo, María L; Vallet-Regí, María; Esbrit, Pedro

    2016-08-01

    Diabetes mellitus (DM) and aging are associated with bone fragility and increased fracture risk. Both (1-37) N- and (107-111) C-terminal parathyroid hormone-related protein (PTHrP) exhibit osteogenic properties. We here aimed to evaluate and compare the efficacy of either PTHrP (1-37) or PTHrP (107-111) loaded into gelatin-glutaraldehyde-coated hydroxyapatite (HA-Gel) foams to improve bone repair of a transcortical tibial defect in aging rats with or without DM, induced by streptozotocin injection at birth. Diabetic old rats showed bone structural deterioration compared to their age-matched controls. Histological and μ-computerized tomography studies showed incomplete bone repair at 4 weeks after implantation of unloaded Ha-Gel foams in the transcortical tibial defects, mainly in old rats with DM. However, enhanced defect healing, as shown by an increase of bone volume/tissue volume and trabecular and cortical thickness and decreased trabecular separation, occurred in the presence of either PTHrP peptide in the implants in old rats with or without DM. This was accompanied by newly formed bone tissue around the osteointegrated HA-Gel implant and increased gene expression of osteocalcin and vascular endothelial growth factor (bone formation and angiogenic markers, respectively), and decreased expression of Sost gene, a negative regulator of bone formation, in the healing bone area. Our findings suggest that local delivery of PTHrP (1-37) or PTHrP (107-111) from a degradable implant is an attractive strategy to improve bone regeneration in aged and diabetic subjects. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2060-2070, 2016. PMID:27086979

  8. Increased metallothionein in mouse liver, kidneys, and duodenum during lactation.

    PubMed

    Solaiman, D; Jonah, M M; Miyazaki, W; Ho, G; Bhattacharyya, M H

    2001-03-01

    Lactation-induced increases in cadmium absorption and retention have been demonstrated in mid-lactating mice, but no systematic measurements of endogenous metal-binding protein concentrations during lactation have been reported. Using Cd/hemoglobin radioassay, this study detected significant increases in metallothionein (MT) concentrations in liver (4-fold), kidneys (2-fold), and duodenum (2-fold), but not jejunum, of mouse dams on days 13 and 20 of lactation. These increases occurred in the absence of cadmium exposure and were specific to the lactation period; dams 5 days after weaning showed MT levels that were similar to those of nonpregnant (NP) mice. Similarly, Northern blot analyses of livers from lactating mice demonstrated that MT mRNA concentrations in maternal liver during mid-lactation were 6-fold higher than those observed 5 days after pups were weaned. Gel filtration of final supernatants from the Cd/hemoglobin assay confirmed that the Cd-binding molecule induced during lactation was indeed metallothionein. In addition, chromatographic analyses of cytosols from tissues taken from dams administered small amounts of Cd (66 ng/mouse) showed that the trace amounts of Cd absorbed through the maternal gastrointestinal tract during mid-lactation were also bound to the MT. These results indicate MT induction in mouse dams occurs as a physiological consequence of lactation, requiring no external stimulus. This induced MT participates in binding low levels of dietary cadmium consumed by the dam. During lactation, elevated maternal MT may affect pathways for essential trace metals as well as sequester toxic metals harmful to the neonate. Multiparous humans may have increased risk of accumulating environmental Cd. PMID:11222885

  9. Tumour-derived PTH-related protein triggers adipose tissue browning and cancer cachexia.

    PubMed

    Kir, Serkan; White, James P; Kleiner, Sandra; Kazak, Lawrence; Cohen, Paul; Baracos, Vickie E; Spiegelman, Bruce M

    2014-09-01

    Cachexia is a wasting disorder of adipose and skeletal muscle tissues that leads to profound weight loss and frailty. About half of all cancer patients suffer from cachexia, which impairs quality of life, limits cancer therapy and decreases survival. One key characteristic of cachexia is higher resting energy expenditure levels than in healthy individuals, which has been linked to greater thermogenesis by brown fat. How tumours induce brown fat activity is unknown. Here, using a Lewis lung carcinoma model of cancer cachexia, we show that tumour-derived parathyroid-hormone-related protein (PTHrP) has an important role in wasting, through driving the expression of genes involved in thermogenesis in adipose tissues. Neutralization of PTHrP in tumour-bearing mice blocked adipose tissue browning and the loss of muscle mass and strength. Our results demonstrate that PTHrP mediates energy wasting in fat tissues and contributes to the broader aspects of cancer cachexia. Thus, neutralization of PTHrP might hold promise for ameliorating cancer cachexia and improving patient survival. PMID:25043053

  10. Effects of Dexamethasone and Insulin Alone or in Combination on Energy and Protein Metabolism Indicators and Milk Production in Dairy Cows in Early Lactation – A Randomized Controlled Trial

    PubMed Central

    Sami, Mehrdad; Mohri, Mehrdad; Seifi, Hesam A.

    2015-01-01

    Objectives This study investigated the effects of dexamethasone and insulin, when administered at 3rd or 10th day of lactation on energy and protein metabolism in dairy cows. Materials and Methods Two hundred Holstein cows were enrolled in a randomized controlled clinical trial. The cows were randomly assigned to receive 1 of 4 treatments at 3 or 10 days in milk: control group, 10-mL i.m. injection of sterile water, group insulin, s.c. injection of 100 units of insulin, group dexamethasone, i.m. injection of 20 mg of dexamethasone, group insulin plus dexamethasone, i.m. injection of 20 mg of dexamethasone and 100 units of insulin. The cows randomly assigned to receive the treatments on 3 or 10 days of lactation. Serum samples obtained at the time of enrollment, time of treatment and at 2, 4, 7 and 14 days after intervention. The sera were analyzed for β-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), glucose, cholesterol, albumin, urea, and aspartate amino transferase (AST). Data were analyzed using a repeated measures mixed model that accounted for the effects of parity, body condition score, dystocia, retained placenta, metritis and the random effect of cow. Results There was no significant interaction of group of treatment and time of intervention (day 3 or 10 post-partum) on serum components. Cows that received insulin or dexamethasone alone or in combination, had lower BHBA 2 days after treatment compared with control cows, whereas concentrations of NEFA, were unaffected suggesting that glucocorticoids lipolytic effects do not appear to be important in healthy cows. AST activities significantly reduced in cows that received dexamethasone with or without insulin at 2 and 4 days after treatment. Albumin and urea concentrations 2 days after treatment were higher for cows that received dexamethasone only or dexamethasone plus insulin compared with control and Ins received cows. There were no treatment effects on test-day milk production, milk fat and

  11. Effect of stage of lactation on the immune competence of goat mammary gland.

    PubMed

    Albenzio, M; Santillo, A; Caroprese, M; Ciliberti, M G; Marino, R; Sevi, A

    2016-05-01

    The present research was undertaken to evaluate the effect of stage of lactation on immune competence of the goat mammary gland. The prevalence and etiology of intramammary infections and cytokine pattern were studied in individual caprine milk during lactation. A total of 1,200 caprine milk samples were collected during early, mid, and late lactation (less than 40 d, from 110 to 130 d, and more than 200 d in lactation, respectively) and analyzed for milk quality, bacterial cell load, and cytokine pattern. Contagious and environmental pathogens associated with intramammary infection were isolated from caprine milk. Nutritional components of caprine milk were affected by stage of lactation; fat, protein, casein, and whey protein increased along with lactation due to the lowest milk yield. Lactose content showed an opposite trend, with a reduced percentage passing from early to late lactation. The impaired rheological properties detected in early and late lactation milk were associated with a modification of milk quality. An impairment of microbial quality was detected at the end of lactation as a consequence of a major susceptibility of mammary gland to infections. The percentage of bacteriologically positive caprine milk samples was 44% throughout lactation. The incidence of bacteria associated with intramammary infection was different according to the stage of lactation with a major prevalence of Staphylococcus aureus, Enterobacteriaceae, Staphylococcus hyicus, and Streptococcus uberis in early lactation milk, Staphylococcus chromogenes, Streptococcus bovis, and Staphylococcus epidermidis in mid lactation, and Pseudomonas aeruginosa and Staphylococcus caprae in late lactation milk. The higher values of IL-1β, tumor necrosis factor-α, and IL-6 were ascribed to the major prevalence of Staphylococcus aureus at the beginning of lactation, whereas a higher level of IL-10 was detected in mid-lactation caprine milk and correlated with Staphylococcus chromogenes

  12. Alcohol's effect on lactation.

    PubMed

    Mennella, J

    2001-01-01

    Although pregnant women are discouraged from drinking alcohol because of alcohol's detrimental effect on fetal development, the lore of many cultures encourages lactating women to drink alcohol to optimize breast milk production and infant nutrition. In contrast to this folklore, however, studies demonstrate that maternal alcohol consumption may slightly reduce milk production. Furthermore, some of the alcohol consumed by a lactating woman is transferred to her milk and thus consumed by the infant. This alcohol consumption may adversely affect the infant's sleep and gross motor development and influence early learning about alcohol. Based on this science, it would seem that the recommendation for a nursing mother to drink a glass of beer or wine shortly before nursing may actually be counterproductive. PMID:11810962

  13. Gastrointestinal transport of calcium and glucose in lactating ewes.

    PubMed

    Klinger, Stefanie; Schröder, Bernd; Gemmer, Anja; Reimers, Julia; Breves, Gerhard; Herrmann, Jens; Wilkens, Mirja R

    2016-06-01

    During lactation, mineral and nutrient requirements increase dramatically, particularly those for Ca and glucose. In contrast to monogastric species, in ruminants, it is rather unclear to which extend this physiological change due to increased demand for milk production is accompanied by functional adaptations of the gastrointestinal tract (GIT). Therefore, we investigated potential modulations of Ca and glucose transport mechanisms in the GIT of lactating and dried-off sheep. Ussing-chamber technique was applied to determine the ruminal and jejunal Ca flux rates. In the jejunum, electrophysiological properties in response to glucose were recorded. Jejunal brush-border membrane vesicles (BBMV) served to characterize glucose uptake via sodium-linked glucose transporter 1 (SGLT1), and RNA and protein expression levels of Ca and glucose transporting systems were determined. Ruminal Ca flux rate data showed a trend for higher absorption in lactating sheep. In the jejunum, small Ca absorption could only be observed in lactating ewes. From the results, it may be assumed that lactating ewes compensate for the Ca loss by increasing bone mobilization rather than by increasing supply through absorption from the GIT Presence of SGLT1 in the jejunum of both groups was shown by RNA and protein identification, but glucose uptake into BBMV could only be detected in lactating sheep. This, however, could not be attributed to electrogenic glucose absorption in lactating sheep under Ussing-chamber conditions, providing evidence that changes in jejunal glucose uptake may include additional factors, that is, posttranslational modifications such as phosphorylation. PMID:27273883

  14. Microbial production of lactate-containing polyesters

    PubMed Central

    Yang, Jung Eun; Choi, So Young; Shin, Jae Ho; Park, Si Jae; Lee, Sang Yup

    2013-01-01

    Due to our increasing concerns on environmental problems and limited fossil resources, biobased production of chemicals and materials through biorefinery has been attracting much attention. Optimization of the metabolic performance of microorganisms, the key biocatalysts for the efficient production of the desired target bioproducts, has been achieved by metabolic engineering. Metabolic engineering allowed more efficient production of polyhydroxyalkanoates, a family of microbial polyesters. More recently, non-natural polyesters containing lactate as a monomer have also been produced by one-step fermentation of engineered bacteria. Systems metabolic engineering integrating traditional metabolic engineering with systems biology, synthetic biology, protein/enzyme engineering through directed evolution and structural design, and evolutionary engineering, enabled microorganisms to efficiently produce natural and non-natural products. Here, we review the strategies for the metabolic engineering of microorganisms for the in vivo biosynthesis of lactate-containing polyesters and for the optimization of whole cell metabolism to efficiently produce lactate-containing polyesters. Also, major problems to be solved to further enhance the production of lactate-containing polyesters are discussed. PMID:23718266

  15. A study of Lusitano mare lactation curve with Wood's model.

    PubMed

    Santos, A S; Silvestre, A M

    2008-02-01

    Milk yield and composition data from 7 nursing Lusitano mares (450 to 580 kg of body weight and 2 to 9 parities) were used in this study (5 measurements per mare for milk yield and 8 measurements for composition). Wood's lactation model was used to describe milk fat, protein, and lactose lactation curves. Mean values for the concentration of major milk components across the lactation period (180 d) were 5.9 g/kg of fat, 18.4 g/kg of protein, and 60.8 g/kg of lactose. Milk fat and protein (g/kg) decreased and lactose (g/kg) increased during the 180 d of lactation. Curves for milk protein and lactose yields (g) were similar in shape to the milk yield curve; protein yield peaked at 307 g on d 10 and lactose peaked at 816 g on d 45. The fat (g) curve was different in shape compared with milk, protein, and lactose yields. Total production of the major milk constituents throughout the 180 d of lactation was estimated to be 12.0, 36.1, and 124 kg for fat, protein, and lactose, respectively. The algebraic model fitted by a nonlinear regression procedure to the data resulted in reasonable prediction curves for milk yield (R(a)(2) of 0.89) and the major constituents (R(a)(2) ranged from 0.89 to 0.95). The lactation curves of major milk constituents in Lusitano mares were similar, both in shape and values, to those found in other horse breeds. The established curves facilitate the estimation of milk yield and variation of milk constituents at different stages of lactation for both nursing and dairy mares, providing important information relative to weaning time and foal supplementation. PMID:18218764

  16. Lactation transcriptomics in the Australian marsupial, Macropus eugenii: transcript sequencing and quantification

    PubMed Central

    Lefèvre, Christophe M; Digby, Matthew R; Whitley, Jane C; Strahm, Yvan; Nicholas, Kevin R

    2007-01-01

    Background Lactation is an important aspect of mammalian biology and, amongst mammals, marsupials show one of the most complex lactation cycles. Marsupials, such as the tammar wallaby (Macropus eugenii) give birth to a relatively immature newborn and progressive changes in milk composition and milk production regulate early stage development of the young. Results In order to investigate gene expression in the marsupial mammary gland during lactation, a comprehensive set of cDNA libraries was derived from lactating tissues throughout the lactation cycle of the tammar wallaby. A total of 14,837 express sequence tags were produced by cDNA sequencing. Sequence analysis and sequence assembly were used to construct a comprehensive catalogue of mammary transcripts. Sequence data from pregnant and early or late lactating specific cDNA libraries and, data from early or late lactation massively parallel sequencing strategies were combined to analyse the variation of milk protein gene expression during the lactation cycle. Conclusion Results show a steady increase in expression of genes coding for secreted protein during the lactation cycle that is associated with high proportion of transcripts coding for milk proteins. In addition, genes involved in immune function, translation and energy or anabolic metabolism are expressed across the lactation cycle. A number of potential new milk proteins or mammary gland remodelling markers, including noncoding RNAs have been identified. PMID:17997866

  17. L-lactate transport in Ehrlich ascites-tumour cells.

    PubMed

    Spencer, T L; Lehninger, A L

    1976-02-15

    Ehrlich ascites-tumour cells were investigated with regard to their stability to transport L-lactate by measuring either the distribution of [14C]lactate or concomitant H+ ion movements. The movement of lactate was dependent on the pH difference across the cell membrane and was electroneutral, as evidenced by an observed 1:1 antiport for OH- ions or 1:1 symport with H+ ions. 2. Kinetic experiments showed that lactate transport was saturable, with an apparent Km of approx. 4.68 mM and a Vmax. as high as 680 nmol/min per mg of protein at pH 6.2 and 37 degrees C. 3. Lactate transport exhibited a high temperature dependence (activation energy = 139 kJ/mol). 4. Lactate transport was inhibited competitively by (a) a variety of other substituted monocarboxylic acids (e.g. pyruvate, Ki = 6.3 mM), which were themselves transported, (b) the non-transportable analogues alpha-cyano-4-hydroxycinnamate (Ki = 0.5 mM), alpha-cyano-3-hydroxycinnamate (Ki = 2mM) and DL-p-hydroxyphenyl-lactate (Ki = 3.6 mM) and (c) the thiol-group reagent mersalyl (Ki = 125 muM). 5. Transport of simple monocarboxylic acids, including acetate and propionate, was insensitive to these inhibitors; they presumably cross the membrane by means of a different mechanism. 6. Experiments using saturating amounts of mersalyl as an "inhibitor stop" allowed measurements of the initial rates of net influx and of net efflux of [14C]lactate. Influx and efflux of lactate were judged to be symmetrical reactions in that they exhibited similar concentration dependence. 7. It is concluded that lactate transport in Ehrlich ascites-tumour cells is mediated by a carrier capable of transporting a number of other substituted monocarboxylic acids, but not unsubstituted short-chain aliphatic acids. PMID:7237

  18. Hormonal contraception and lactation.

    PubMed

    Kelsey, J J

    1996-12-01

    Hormonal contraceptive measures can be used immediately postpartum if the patient so desires. Progestin-only contraceptives are preferable to estrogen-containing methods if initiated during the first six months after delivery. Progestin only contraceptives do not appear to affect milk volume, composition, or to cause deleterious effects in the infant. Ideally for women who desire a form of contraception in addition to lactation-induced amenorrhea, progestin-only methods should be started at six weeks postpartum if the woman is fully breastfeeding. Since contraception protection is provided by lactation amenorrhea, the six week delay will decrease infant exposure to exogenous hormones and decrease the incidence of irregular postpartum bleeding. Milk volume may decrease with the use of estrogen; however, no detrimental effects have been shown on infant growth or development. For women who are planning to gradually wean their infant, use of COCs may provide an easier transition to bottle-feeding. COCs should be used with caution by women who are not able to obtain supplemental milk. A decrease in milk volume can lead to earlier discontinuation of the hormonal contraceptive in an attempt to increase milk quantity. Supplementation is often needed, and then the woman ovulates again, possibly resulting in an unintended pregnancy. Many women are motivated immediately postpartum to accept contraception. For other women, lack of access to health care may provide barriers in obtaining adequate contraception later. In either case, there are adequate data to show no detriments of starting progestin-only contraceptives within days of delivery. Therefore, the best method for the patient should be employed to ensure adequate contraception while preserving optimal lactation. PMID:9025449

  19. Partial reconstruction of in vitro gluconeogenesis arising from mitochondrial l-lactate uptake/metabolism and oxaloacetate export via novel L-lactate translocators.

    PubMed Central

    De Bari, Lidia; Atlante, Anna; Valenti, Daniela; Passarella, Salvatore

    2004-01-01

    In the light of the occurrence of L-lactate dehydrogenase inside the mitochondrial matrix, we looked at whether isolated rat liver mitochondria can take up and metabolize L-lactate, and provide oxaloacetate outside mitochondria, thus contributing to a partial reconstruction of gluconeogenesis in vitro. We found that: (1) L-lactate (10 mM), added to mitochondria in the presence of a cocktail of glycolysis/gluconeogenesis enzymes and cofactors, can lead to synthesis of glyceraldehyde-3-phosphate at a rate of about 7 nmol/min per mg mitochondrial protein. (2) Three novel translocators exist to mediate L-lactate traffic across the inner mitochondrial membrane. An L-lactate/H+ symporter was identified by measuring fluorimetrically the rate of endogenous pyridine nucleotide reduction. Consistently, L-lactate oxidation was found to occur with P/O ratio=3 (where P/O ratio is the ratio of mol of ATP synthesized to mol of oxygen atoms reduced to water during oxidative phosphorylation) and with generation of membrane potential. Proton uptake, which occurred as a result of addition of L-lactate to RLM together with electron flow inhibitors, and mitochondrial swelling in ammonium L-lactate solutions were also monitored. L-Lactate/oxaloacetate and L-lactate/pyruvate anti-porters were identified by monitoring photometrically the appearance of L-lactate counter-anions outside mitochondria. These L-lactate translocators, which are distinct from the monocarboxylate carrier, were found to differ from each other in V(max) values and in inhibition and pH profiles, and proved to regulate mitochondrial L-lactate metabolism in vitro. The role of lactate/mitochondria interactions in gluconeogenesis is discussed. PMID:14960150

  20. Metabolic adaptations in goat mammary tissue during pregnancy and lactation.

    PubMed

    Wilde, C J; Henderson, A J; Knight, C H

    1986-01-01

    Metabolic adaptations of goat mammary tissue during pregnancy and lactation were monitored in serial biopsies of the tissue. Changes in the synthetic capacity of secretory cells were studied by combining measurements of enzyme activities with short-term culture of mammary explants to measure lactose, casein and total protein synthesis. By these criteria, the main phase of mammary differentiation began in late pregnancy and was essentially complete by Week 5 of lactation, coinciding with the achievement of peak milk yield. While milk yield declined after Week 5, the activities of key enzymes expressed per mg DNA and the rates of lactose and casein synthesis in mammary explants were maintained over a considerable period. The results suggest that changes in the synthetic capacity of epithelial cells may account for much of the rise in milk yield in early lactation, but are not responsible for the declining phase of milk production characteristic of lactation in ruminants. PMID:2868125

  1. Does protein intake alter the precursors for synthesis of lactose and non-essential amino acids by the mammary glands of lactating mice?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aims were to: 1) develop a [U-13C]glucose tracer approach to establish the pathways of and substrates used for milk lactose and casein synthesis in the mouse mammary gland and 2) determine the influence of protein intake on this partition and use for milk synthesis. In Study 1, we determined th...

  2. Short-term administration of rhGH increases markers of cellular proliferation, but not milk protein gene expression in normal lactating women.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growth hormone is one of few pharmacologic agents known to augment milk production in humans. We hypothesized that recombinant human GH (rhGH) increases the expression of cell proliferation and milk protein synthesis genes. Sequential milk and blood samples collected over four days were obtained fro...

  3. Supplementing rumen-protected methionine and lysine in low-protein diets based on corn distillers grains fed to lactating dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feeding rumen-protected methionine (RPM) and lysine (RPL) may allow feeding lower crude protein (CP) diets to dairy cows, thereby increasing nitrogen efficiency and reducing environmental impact. Moreover, RPL supplementation may improve the value of corn distillers dried grains plus solubles (DDGS)...

  4. Channel-mediated lactate release by K⁺-stimulated astrocytes.

    PubMed

    Sotelo-Hitschfeld, Tamara; Niemeyer, María I; Mächler, Philipp; Ruminot, Iván; Lerchundi, Rodrigo; Wyss, Matthias T; Stobart, Jillian; Fernández-Moncada, Ignacio; Valdebenito, Rocío; Garrido-Gerter, Pamela; Contreras-Baeza, Yasna; Schneider, Bernard L; Aebischer, Patrick; Lengacher, Sylvain; San Martín, Alejandro; Le Douce, Juliette; Bonvento, Gilles; Magistretti, Pierre J; Sepúlveda, Francisco V; Weber, Bruno; Barros, L Felipe

    2015-03-11

    Excitatory synaptic transmission is accompanied by a local surge in interstitial lactate that occurs despite adequate oxygen availability, a puzzling phenomenon termed aerobic glycolysis. In addition to its role as an energy substrate, recent studies have shown that lactate modulates neuronal excitability acting through various targets, including NMDA receptors and G-protein-coupled receptors specific for lactate, but little is known about the cellular and molecular mechanisms responsible for the increase in interstitial lactate. Using a panel of genetically encoded fluorescence nanosensors for energy metabolites, we show here that mouse astrocytes in culture, in cortical slices, and in vivo maintain a steady-state reservoir of lactate. The reservoir was released to the extracellular space immediately after exposure of astrocytes to a physiological rise in extracellular K(+) or cell depolarization. Cell-attached patch-clamp analysis of cultured astrocytes revealed a 37 pS lactate-permeable ion channel activated by cell depolarization. The channel was modulated by lactate itself, resulting in a positive feedback loop for lactate release. A rapid fall in intracellular lactate levels was also observed in cortical astrocytes of anesthetized mice in response to local field stimulation. The existence of an astrocytic lactate reservoir and its quick mobilization via an ion channel in response to a neuronal cue provides fresh support to lactate roles in neuronal fueling and in gliotransmission. PMID:25762664

  5. THE CONSUMPTION OF RED PUPUNHA (BACTRIS GASIPAES KUNTH) INCREASES HDL CHOLESTEROL AND REDUCES WEIGHT GAIN OF LACTATING AND POST-LACTATING WISTAR RATS

    PubMed Central

    Carvalho, R. Piccolotto; Lemos, J.R. Gonzaga; de Aquino Sales, R. Souza; Martins, M. Gassen; Nascimento, C.H.; Bayona, M.; Marcon, J.L.; Monteiro, J. Barros

    2014-01-01

    Introduction The lactating and post-lactating periods are marked by large metabolic change. Production of milk is 60% lipid dependent. We reported in a recent scientific meeting that Red pupunha palm tree fruit increases HDL cholesterol in lactating rats. This study evaluated if consumption of Red Pupunha by adult female rats has a beneficial impact on the lipid metabolism of lacting and post-lacting adult rats. Objective Evaluate if consumption of red pupunha has a beneficial effect in the lipid metabolism of lacting and post-lacting adult Wistar rats. Research Methods Four groups including two for control; (1) control adult lactating rats, (2) control adults post-lactating rats; and two experimental groups; (3) pupunha adults lactating rats and (4) pupunha adult post-lactating rats were evaluated and compared regarding: weight gain, food consumption, plasma total protein, glucose, total lipid, triglycerides, total cholesterol and HDL-cholesterol levels. The mean difference and its 95% confidence intervals were used for group comparisons. Group comparisons were evaluated by using analysis of variance (one-way ANOVA). The statistical significance of the pairwise differences among groups was assessed by using the two-sided Tukey test. Results There were no important differences in food consumption, plasma glucose, total lipids and triglycerides among groups. The red pupunha lactating group gain less weight showing lower body mass index (BMI) than controls (p < 0.05). Total cholesterol was lower in red pupunha lactating than in controls but not in the red pupunha post-lactating group as compared to controls. Triglycerides were lower in the post-lactating red pupunha group as compared to the control group (p = 0.039) but not for the lactating groups. Red pupunha lactating and post-lactating groups had higher HDL-cholesterol than their corresponding control groups (p ≤ 0.01). Conclusion Original findings include the beneficial effect of red pupunha in post-lactating

  6. Jussara (Euterpe edulis Mart.) Supplementation during Pregnancy and Lactation Modulates the Gene and Protein Expression of Inflammation Biomarkers Induced by trans-Fatty Acids in the Colon of Offspring

    PubMed Central

    Almeida Morais, Carina; Oyama, Lila Missae; de Oliveira, Juliana Lopez; Carvalho Garcia, Márcia; de Rosso, Veridiana Vera; Sousa Mendes Amigo, Laís; do Nascimento, Claudia Maria Oller; Pisani, Luciana Pellegrini

    2014-01-01

    Maternal intake of trans-fatty acids (TFAs) in the perinatal period triggers a proinflammatory state in offspring. Anthocyanins contained in fruit are promising modulators of inflammation. This study investigated the effect of Jussara supplementation in the maternal diet on the proinflammatory state of the colon in offspring exposed to perinatal TFAs. On the first day of pregnancy rats were divided into four groups: control diet (C), control diet with 0.5% Jussara supplementation (CJ), diet enriched with hydrogenated vegetable fat, rich in TFAs (T), or T diet supplemented with 0.5% Jussara (TJ) during pregnancy and lactation. We showed that Jussara supplementation in maternal diet (CJ and TJ groups) reduced carcass lipid/protein ratios, serum lipids, glucose, IL-6, TNF-α, gene expression of IL-6R, TNF-αR (P < 0.05), TLR-4 (P < 0.01), and increase Lactobacillus spp. (P < 0.05) in the colon of offspring compared to the T group. The IL-10 (P = 0.035) and IL-10/TNF-α ratio (P < 0.01) was higher in the CJ group than in the T group. The 0.5% Jussara supplementation reverses the adverse effects of perinatal TFAs, improving lipid profiles, glucose levels, body composition, and gut microbiota and reducing low-grade inflammation in the colon of 21-day-old offspring, and could contribute to reducing chronic disease development. PMID:25276060

  7. Best prediction of yields for long lactations.

    PubMed

    Cole, J B; Null, D J; Vanraden, P M

    2009-04-01

    Lactation records of any reasonable length now can be processed with the selection index method known as best prediction (BP). Previous prediction programs were limited to the 305-d standard used since 1935. Best prediction was implemented in 1998 to calculate lactation records in USDA genetic evaluations, replacing the test interval method used since 1969 to calculate lactation records. Best prediction is more complex but also more accurate, particularly when testing is less frequent. Programs were reorganized to output better graphics, give users simpler access to options, and provide additional output, such as BP of daily yields. Test-day data for 6 breeds were extracted from the national dairy database, and lactation lengths were required to be > or =500 d (Ayrshire, Milking Shorthorn) or > or =800 d (all others). Average yield and SD at any day in milk (DIM) were estimated by fitting 3-parameter Wood's curves (milk, fat, protein) and 4-parameter exponential functions (somatic cell score) to means and SD of 15- (< or =300 DIM) and 30-d (>300 DIM) intervals. Correlations among TD yields were estimated using an autoregressive matrix to account for biological changes and an identity matrix to model daily measurement error. Autoregressive parameters (r) were estimated separately for first (r = 0.998) and later parities (r = 0.995). These r values were slightly larger than previous estimates due to the inclusion of the identity matrix. Correlations between traits were modified so that correlations between somatic cell score and other traits may be nonzero. The new lactation curves and correlation functions were validated by extracting TD data from the national database, estimating 305-d yields using the original and new programs, and correlating those results. Daily BP of yield were validated using daily milk weights from on-farm meters in university research herds. Correlations ranged from 0.900 to 0.988 for 305-d milk yield. High correlations ranged from 0.844 to

  8. Lactate and lactate clearance in acute cardiac care patients

    PubMed Central

    Lazzeri, Chiara; Picariello, Claudio; Dini, Carlotta Sorini; Gensini, Gian Franco; Valente, Serafina

    2012-01-01

    Hyperlactataemia is commonly used as a diagnostic and prognostic tool in intensive care settings. Recent studies documented that serial lactate measurements over time (or lactate clearance), may be clinically more reliable than lactate absolute value for risk stratification in different pathological conditions. While the negative prognostic role of hyperlactataemia in several critical ill diseases (such as sepsis and trauma) is well established, data in patients with acute cardiac conditions (i.e. acute coronary syndromes) are scarce and controversial. The present paper provides an overview of the current available evidence on the clinical role of lactic acid levels and lactate clearance in acute cardiac settings (acute coronary syndromes, cardiogenic shock, cardiac surgery), focusing on its prognostic role. PMID:24062898

  9. Migraine in pregnancy and lactation.

    PubMed

    David, Paru S; Kling, Juliana M; Starling, Amaal J

    2014-04-01

    Migraine headache is a significant health problem affecting women more than men. In women, the hormonal fluctuations seen during pregnancy and lactation can affect migraine frequency and magnitude. Understanding the evaluation of headache in pregnancy is important, especially given the increased risk of secondary headache conditions. Pregnancy and lactation can complicate treatment options for women with migraine because of the risk of certain medications to the fetus. This review includes details of the workup and then provides treatment options for migraine during pregnancy and lactation. PMID:24604057

  10. Utility of inline milk fat and protein ratio to diagnose subclinical ketosis and to assign propylene glycol treatment in lactating dairy cows

    PubMed Central

    Jenkins, Nicholas T.; Peña, Gustavo; Risco, Carlos; Barbosa, Carolina C.; Vieira-Neto, Achilles; Galvão, Klibs N.

    2015-01-01

    The objective was to identify a fat-to-protein ratio (FPR) cut-off to diagnose subclinical ketosis (SCK) and to evaluate the effect of propylene glycol (PPG) treatment of cows with high FPR. The optimized cut-off was > 1.42; sensitivity (Se) = 92%; specificity (Sp) = 65%. A cut-off > 1.5 was selected for the PPG trial for balanced Se-Sp. Fat-to-protein ratio cut-offs > 1.25, 1.35, 1.50, 1.60, and 1.70 resulted in Se-Sp of 100% to 49%, 96% to 59%, 75% to 78%, 33% to 90%, and 8% to 96%, respectively. The proportions of cows with FPR > 1.25, 1.35, 1.42, 1.50, 1.60, and 1.70 were 60%, 50%, 44%, 30%, 14%, and 6%, respectively. Incidences of clinical ketosis and milk yield were similar between cows that received 400 mL of PPG (n = 34) and control cows (n = 38). Prevalence of SCK at enrollment was 29.2%; therefore, FPR > 1.5 is not indicated for treatment. Lower cut-offs should be used for screening. PMID:26246632

  11. IL-4 and IL-13 induce protection from complement and melittin in endothelial cells despite initial loss of cytoplasmic proteins: Membrane resealing impairs quantifying cytotoxicity with the lactate dehydrogenase permeability assay

    PubMed Central

    Benson, Barbara A.; Vercellotti, Gregory M.; Dalmasso, Agustin P.

    2015-01-01

    Background Endothelial cell activation and injury by the terminal pathway of complement is important in various pathobiological processes, including xenograft rejection. Protection against injury by human complement can be induced in porcine endothelial cells (ECs) with IL-4 and IL-13 through metabolic activation. However, despite this resistance, the complement-treated ECs were found to lose membrane permeability control assessed with the small molecule calcein. Therefore to define the apparent discrepancy of permeability changes vis-à-vis the protection from killing we now investigated whether IL-4 and IL-13 influence the release of the large cytoplasmic protein lactate dehydrogenase (LDH) in ECs incubated with complement or the pore-forming protein melittin. Methods Primary cultures of ECs were pretreated with IL-4 or IL-13 and then incubated with human serum as source of antibody and complement or melittin. Cell death was assessed using neutral red. Membrane permeability was quantitated measuring LDH release. Results We found that IL-4/IL-13 induced protection of ECs from killing by complement or melittin despite loss of LDH in amounts similar to control ECs. However, the cytokine-treated ECs that were protected from killing rapidly regained effective control of membrane permeability. Moreover, the viability of the protected ECs was maintained for at least 2 days. Conclusion We conclude that the protection induced by IL-4/IL-13 in ECs against lethal attack by complement or melittin is effective and durable despite severe initial impairment of membrane permeability. The metabolic changes responsible for protection allow the cells to repair the membrane injury caused by complement or melittin. PMID:26031609

  12. IL-4 and IL-13 induce protection from complement and melittin in endothelial cells despite initial loss of cytoplasmic proteins: membrane resealing impairs quantifying cytotoxicity with the lactate dehydrogenase permeability assay.

    PubMed

    Benson, Barbara A; Vercellotti, Gregory M; Dalmasso, Agustin P

    2015-01-01

    Endothelial cell activation and injury by the terminal pathway of complement is important in various pathobiological processes, including xenograft rejection. Protection against injury by human complement can be induced in porcine endothelial cells (ECs) with IL-4 and IL-13 through metabolic activation. However, despite this resistance, the complement-treated ECs were found to lose membrane permeability control assessed with the small molecule calcein. Therefore, to define the apparent discrepancy of permeability changes vis-à-vis the protection from killing, we now investigated whether IL-4 and IL-13 influence the release of the large cytoplasmic protein lactate dehydrogenase (LDH) in ECs incubated with complement or the pore-forming protein melittin. Primary cultures of ECs were pre-treated with IL-4 or IL-13 and then incubated with human serum as source of antibody and complement or melittin. Cell death was assessed using neutral red. Membrane permeability was quantitated measuring LDH release. We found that IL-4-/IL-13-induced protection of ECs from killing by complement or melittin despite loss of LDH in amounts similar to control ECs. However, the cytokine-treated ECs that were protected from killing rapidly regained effective control of membrane permeability. Moreover, the viability of the protected ECs was maintained for at least 2 days. We conclude that the protection induced by IL-4/IL-13 in ECs against lethal attack by complement or melittin is effective and durable despite severe initial impairment of membrane permeability. The metabolic changes responsible for protection allow the cells to repair the membrane injury caused by complement or melittin. PMID:26031609

  13. Effects of Pregnancy and Lactation on Iron Metabolism in Rats

    PubMed Central

    Gao, Guofen; Liu, Shang-Yuan; Wang, Hui-Jie; Zhang, Tian-Wei; Yu, Peng; Duan, Xiang-Lin; Zhao, Shu-E; Chang, Yan-Zhong

    2015-01-01

    In female, inadequate iron supply is a highly prevalent problem that often leads to iron-deficiency anemia. This study aimed to understand the effects of pregnancy and lactation on iron metabolism. Rats with different days of gestation and lactation were used to determine the variations in iron stores and serum iron level and the changes in expression of iron metabolism-related proteins, including ferritin, ferroportin 1 (FPN1), ceruloplasmin (Cp), divalent metal transporter 1 (DMT1), transferrin receptor 1 (TfR1), and the major iron-regulatory molecule—hepcidin. We found that iron stores decline dramatically at late-pregnancy period, and the low iron store status persists throughout the lactation period. The significantly increased FPN1 level in small intestine facilitates digestive iron absorption, which maintains the serum iron concentration at a near-normal level to meet the increase of iron requirements. Moreover, a significant decrease of hepcidin expression is observed during late-pregnancy and early-lactation stages, suggesting the important regulatory role that hepcidin plays in iron metabolism during pregnancy and lactation. These results are fundamental to the understanding of iron homeostasis during pregnancy and lactation and may provide experimental bases for future studies to identify key molecules expressed during these special periods that regulate the expression of hepcidin, to eventually improve the iron-deficiency status. PMID:26788496

  14. Associations of insulin resistance later in lactation on fertility of dairy cows.

    PubMed

    Baruselli, P S; Vieira, L M; Sá Filho, M F; Mingoti, R D; Ferreira, R M; Chiaratti, M R; Oliveira, L H; Sales, J N; Sartori, R

    2016-07-01

    The challenge of getting dairy cows pregnant during early lactation is a well-described, worldwide problem. However, specifically in farms with poor reproductive, nutritional, and environmental conditions/management, a low pregnancy rate during early lactation is followed inevitably by an increased number of nonpregnant cows after 150 days in milk, with even more difficulties to achieve pregnancy. Therefore, several studies were designed to understand and develop strategies to mitigate reduced fertility of cows during late lactation. Experiments were performed under tropical regions to determine metabolic status during lactation and association of stage of lactation on oocyte quality and fertility. Lactating cows with extended days not pregnant (e.g.,>150 days in milk) often had systemic metabolic alterations, including development of peripheral insulin resistance and various oocyte alterations, including reduced expression of genes encoding glucose transport proteins, reduced amounts of mtDNA, increased expression of mitochondria-related genes, and increased expression of apoptosis-related genes. Additionally, in vitro embryo production and pregnancy per AI were lower in late- versus early-lactation cows in some but not all studies. Notwithstanding, when a normal embryo was transferred to a cow in late lactation, the pregnancy per transfer was reasonable, reinforcing the assertion that fertility problems in late-lactation cows may be associated with oocyte quality, fertilization, and/or failure of early embryo development. In conclusion, insulin resistance may reduce oocyte competence and consequently fertility in late-lactation dairy cows. PMID:27158130

  15. Lactate levels with glioblastoma multiforme.

    PubMed

    Kahlon, Arunpreet Singh; Alexander, Mariam; Kahlon, Arundeep; Wright, Jonathan

    2016-07-01

    A 37-year-old woman with known glioblastoma multiforme was admitted for treatment of new deep vein thrombosis. Anion gap and plasma lactate levels were found to be elevated. Magnetic resonance imaging of the brain showed a stable, advanced glioblastoma multiforme. All causes of lactic acidosis, including infections and medications, were ruled out. Aggressive tumors have been shown to produce lactate levels in minute quantities in their microenvironment, which helps them metastasize and evade immune response and even radiation. PMID:27365883

  16. Lactate levels with glioblastoma multiforme

    PubMed Central

    Kahlon, Arunpreet Singh; Alexander, Mariam; Kahlon, Arundeep

    2016-01-01

    A 37-year-old woman with known glioblastoma multiforme was admitted for treatment of new deep vein thrombosis. Anion gap and plasma lactate levels were found to be elevated. Magnetic resonance imaging of the brain showed a stable, advanced glioblastoma multiforme. All causes of lactic acidosis, including infections and medications, were ruled out. Aggressive tumors have been shown to produce lactate levels in minute quantities in their microenvironment, which helps them metastasize and evade immune response and even radiation. PMID:27365883

  17. Lactating Adenoma of the Breast.

    PubMed

    Barco Nebreda, Israel; Vidal, M Carmen; Fraile, Manel; Canales, Lydia; González, Clarisa; Giménez, Nuria; García-Fernández, Antonio

    2016-08-01

    Lactating adenoma is an uncommon breast palpable lesion occurring in pregnancy or lactation. Although it is a benign condition, it often requires core biopsy or even surgery to exclude malignancy. As with other solid lesions in pregnancy and lactation, lactating adenoma needs an accurate evaluation in order to ensure its benign nature. Work-up must include both imaging and histologic findings. Ultrasound evaluation remains the first step in assessing the features of the lesion. Some authors consider magnetic resonance imaging as a useful tool in cases of inconclusive evaluation after ultrasound and histologic exam in an attempt to avoid surgery. Most lactating adenomas resolve spontaneously, whereas others persist or even increase in size and must be removed. The authors present a case of a 35-year-old woman at 6 months postpartum with a lactating adenoma in her right breast. After surgical removal, breastfeeding was perfectly continued within the next 24 hours, which highlights the fact that breast surgery is most often compatible with breastfeeding. PMID:27197575

  18. Feed intake and production parameters of lactating crossbred cows fed maize-based diets of stover, silage or quality protein silage

    PubMed Central

    Gebrehawariat, Efrem; Tegegne, Azage

    2010-01-01

    Thirty-six Boran × Friesian dairy cows (392 ± 12 kg; mean ± SD) in early parity were used in a randomised complete block design. Cows were blocked by parity into three blocks of 12 animals and offered normal maize (NM) stover (T1), NM silage (T2) or quality protein maize (QPM) silage (T3) basal diets supplemented with a similar concentrate mix. Feed intake, body weight and condition changes and milk yield and composition were assessed. The daily intake of DM, OM, NDF and ADF for cows fed the NM stover-based diet was higher (P < 0.05) than for the cows fed the NM silage and QPM silage-based diets. However, the daily intake of DOM (9.3 kg) and ME (140.8 MJ) for cows on QPM silage-based diet was higher (P < 0.05) than for cows on NM stover-based diet (8.4 kg and 124.2 MJ) and NM silage-based diet (7.9 kg and 119.1 MJ). Body weight of cows was affected (P < 0.05) by the diet, but diet had no effect (P > 0.05) on body condition score, milk yield and milk composition. The digestible organic matter in the NM stover-based diet (724 g/kg DM) was lower (P < 0.05) than that in the NM (770 g/kg DM) and QPM silage-based diet (762 g/kg DM). It was concluded that the performances of the cows on the NM silage and QPM silage diets were similar and were not superior to that of the NM stover-based diet. PMID:20577806

  19. Changes in mRNA expression of arcuate nucleus appetite-regulating peptides during lactation in rats

    PubMed Central

    Suzuki, Yoshihiro; Nakahara, Keiko; Maruyama, Keisuke; Okame, Rieko; Ensho, Takuya; Inoue, Yoshiyuki; Murakami, Noboru

    2014-01-01

    The contribution of hypothalamic appetite-regulating peptides to further hyperphagia accompanying the course of lactation in rats was investigated by using PCR array and real-time PCR. Furthermore, changes in the mRNA expression for appetite-regulating peptides in the hypothalamic arcuate nucleus (ARC) were analyzed at all stages of pregnancy and lactation, and also after weaning. Food intake was significantly higher during pregnancy, lactation, and after weaning than during non-lactation periods. During lactation, ARC expression of mRNAs for agouti-related protein (AgRP) and peptide YY was increased, whereas that of mRNAs for proopiomelanocortin (POMC) and cholecystokinin (CCK) was decreased, in comparison with non-lactation periods. The increase in AgRP mRNA expression during lactation was especially marked. The plasma level of leptin was significantly decreased during the course of lactation, whereas that of acyl-ghrelin was unchanged. In addition, food intake was negatively correlated with the plasma leptin level during lactation. This study has clarified synchronous changes in the expression of many appetite-regulating peptides in ARC of rats during lactation. Our results suggest that hyperphagia during lactation in rats is caused by decreases in POMC and CCK expression and increases in AgRP expression in ARC, the latter being most notable. Together with the decrease in the blood leptin level, such changes in mRNA expression may explain the further hyperphagia accompanying the course of lactation. PMID:24299740

  20. Analysis of a Functional Lactate Permease in the Fungus Rhizopus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungus Rhizopus is frequently used for fermentative production of lactic acid, but little is known about the mechanisms or proteins for transporting this carboxylic acid. Since transport of the lactate anion across the plasma membrane is critical to prevent acidification of the cytoplasm, we ev...

  1. Data Collection Ratings and Best Prediction of Lactation Yields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Best prediction (BP) has been used in the US to calculate lactation yields of milk, fat, protein, and somatic cell score (SCS) from test day data since 1998, when it replaced the test interval method (TIM) used since 1969. It is more complex than TIM but also more accurate, particularly when testing...

  2. Novel Lactate Transporters from Carboxylic Acid-Producing Rhizopus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungus Rhizopus is frequently used for fermentative production of lactic acid, but little is known about the mechanisms or proteins for transporting this carboxylic acid. Since transport of the lactate anion across the plasma membrane is critical to prevent acidification of the cytoplasm, we ev...

  3. Application of Wood's model to lactation curve of Italian Heavy Draft horse mares.

    PubMed

    Centoducati, P; Maggiolino, A; De Palo, P; Tateo, A

    2012-10-01

    The aim of this work was to study, using Wood's model, the lactation curve in Italian Heavy Draft horse (IHDH) mares, both for milk yield and composition. Interest in mare's milk has grown for use in human nutrition, as a substitute for human and cow milk for premature newborns and allergic children. For this study, 7 IHDH mares were used. Milk yield was evaluated from d 15 to 180 postpartum (every 15 d). Wood's lactation model was used to describe milk yield, fat, protein, and lactose lactation curves in the first 180 d in milk (DIM), with a prediction to 210 DIM. Mean values recorded across the considered lactation period for milk yield and constituents were 16.11 kg of milk/d, 11.38 g of fat/kg, 15.54 g of protein/kg, and 69.72 g of lactose/kg. The lactation curve showed a peak at 69 DIM, with a persistence index of 6.26. Fat (g/kg) and protein (g/kg) lactation curves decreased during the lactation period; instead, the lactose (g/kg) curve increased from the first to the last DIM. The coefficient of determination values indicated a good model fit by Wood's model application to IHDH mare lactation. The research showed good aptitude of a heavy horse breed, such as IHDH, for milk production. PMID:22901483

  4. Prostate cancer cells metabolize d-lactate inside mitochondria via a D-lactate dehydrogenase which is more active and highly expressed than in normal cells.

    PubMed

    de Bari, Lidia; Moro, Loredana; Passarella, Salvatore

    2013-03-01

    Although D-lactate metabolism has been shown to occur in a variety of mitochondria, the metabolic fate of D-lactate in cancer cells has never been investigated, as it is believed to be exported to the extracellular phase. We show that mitochondria from both cancer (PC-3) and normal (PNT1A) prostate cells can metabolize D-lactate in an energy competent manner. This is due to the mitochondrial D-lactate dehydrogenase, a membrane flavoprotein, the activity and protein level of which are higher in PC-3 than in PNT1A cells, as detected by both kinetic and immunological analysis. D-Lactate can enter prostate mitochondria and cause the export of newly synthesized malate in a carrier-mediated manner, with the rate of malate efflux from mitochondria twofold higher in cancer. PMID:23333299

  5. Comparative Proteomic Insights into the Lactate Responses of Halophilic Salinicoccus roseus W12.

    PubMed

    Wang, Hongyan; Wang, Limin; Yang, Han; Cai, Yumeng; Sun, Lifan; Xue, Yanfen; Yu, Bo; Ma, Yanhe

    2015-01-01

    Extremophiles use adaptive mechanisms to survive in extreme environments, which is of great importance for several biotechnological applications. A halophilic strain, Salinicoccus roseus W12, was isolated from salt lake in Inner Mongolia, China in this study. The ability of the strain to survive under high sodium conditions (including 20% sodium lactate or 25% sodium chloride, [w/v]) made it an ideal host to screen for key factors related to sodium lactate resistance. The proteomic responses to lactate were studied using W12 cells cultivated with or without lactate stress. A total of 1,656 protein spots in sodium lactate-treated culture and 1,843 spots in NaCl-treated culture were detected by 2-dimensional gel electrophoresis, and 32 of 120 significantly altered protein spots (fold change > 2, p < 0.05) were identified by matrix-assisted laser-desorption ionization time-of-flight mass spectrometry. Among 21 successfully identified spots, 19 proteins were upregulated and 2 were downregulated. The identified proteins are mainly involved in metabolism, cellular processes and signaling, and information storage and processing. Transcription studies confirmed that most of the encoding genes were upregulated after the cells were exposed to lactate in 10 min. Cross-protecting and energy metabolism-related proteins played an important role in lactate tolerance for S. roseus W12. PMID:26358621

  6. Comparative Proteomic Insights into the Lactate Responses of Halophilic Salinicoccus roseus W12

    PubMed Central

    Wang, Hongyan; Wang, Limin; Yang, Han; Cai, Yumeng; Sun, Lifan; Xue, Yanfen; Yu, Bo; Ma, Yanhe

    2015-01-01

    Extremophiles use adaptive mechanisms to survive in extreme environments, which is of great importance for several biotechnological applications. A halophilic strain, Salinicoccus roseus W12, was isolated from salt lake in Inner Mongolia, China in this study. The ability of the strain to survive under high sodium conditions (including 20% sodium lactate or 25% sodium chloride, [w/v]) made it an ideal host to screen for key factors related to sodium lactate resistance. The proteomic responses to lactate were studied using W12 cells cultivated with or without lactate stress. A total of 1,656 protein spots in sodium lactate-treated culture and 1,843 spots in NaCl-treated culture were detected by 2-dimensional gel electrophoresis, and 32 of 120 significantly altered protein spots (fold change > 2, p < 0.05) were identified by matrix-assisted laser-desorption ionization time-of-flight mass spectrometry. Among 21 successfully identified spots, 19 proteins were upregulated and 2 were downregulated. The identified proteins are mainly involved in metabolism, cellular processes and signaling, and information storage and processing. Transcription studies confirmed that most of the encoding genes were upregulated after the cells were exposed to lactate in 10 min. Cross-protecting and energy metabolism-related proteins played an important role in lactate tolerance for S. roseus W12. PMID:26358621

  7. Hematological and biochemical findings in pregnant, postfoaling, and lactating jennies.

    PubMed

    Bonelli, F; Rota, A; Corazza, M; Serio, D; Sgorbini, M

    2016-04-15

    The aims of this study were to (1) verify if significant changes occur in hematological and biochemical parameters in jennies during the last 2 months of pregnancy and the first 2 months of lactation, and (2) determine any differences with mares. Hematological and biochemical parameters were evaluated in jennies every 15 days during late pregnancy, parturition, and early lactation. The Kolmogorov-Smirnov test, analysis of variance for repeated measurements and Tukey's multiple comparison test as post hoc were applied. The significance level was set at P < 0.05. Statistical analysis showed differences related to time for Red Blood Cells (RBC) count and Hematocrit (HCT), White Blood Cells (WBC) count, platelet count (PLT), total proteins, blood urea, triglycerides and total cholesterol concentrations, aspartate aminotransferase, gamma-glutamyltransferase, creatine-phosphokinase activities, sodium (Na) and potassium (K). RBC and HCT were higher in late pregnancy than at foaling and during lactation. The relative anemia might be due to increased water ingestion because of fluid losses. The WBC count was higher at foaling than during late pregnancy and lactation. This could be related to the release of cortisol and catecholamine during delivery. The PLT trend showed lower values from delivery to the first 2 months of lactation compared to late gestation. Blood urea increased near parturition, and then remained constant during delivery and lactation, which might be due to the high energy demand at the beginning of lactation. Triglycerides and total cholesterol showed a decrease from delivery through the lactation period. Thus, jennies seem to have a similar metabolism of fats to ponies and draft horse mares, characterized by a greater fat content and mobilization than light breed horses. Aspartate aminotransferase activity decreased at parturition and early lactation, probably because of a predominance of anabolic over catabolic processes during pregnancy. Gamma

  8. Lactate racemase is a nickel-dependent enzyme activated by a widespread maturation system

    PubMed Central

    Desguin, Benoît; Goffin, Philippe; Viaene, Eric; Kleerebezem, Michiel; Martin-Diaconescu, Vlad; Maroney, Michael J; Declercq, Jean-Paul; Soumillion, Patrice; Hols, Pascal

    2014-01-01

    Racemases catalyze the inversion of stereochemistry in biological molecules, giving the organism the ability to use both isomers. Among them, lactate racemase remains unexplored due to its intrinsic instability and lack of molecular characterization. Here we determine the genetic basis of lactate racemization in Lactobacillus plantarum. We show that, unexpectedly, the racemase is a nickel-dependent enzyme with a novel α/β fold. In addition, we decipher the process leading to an active enzyme, which involves the activation of the apo-enzyme by a single nickel-containing maturation protein that requires preactivation by two other accessory proteins. Genomic investigations reveal the wide distribution of the lactate racemase system among prokaryotes, showing the high significance of both lactate enantiomers in carbon metabolism. The even broader distribution of the nickel-based maturation system suggests a function beyond activation of the lactate racemase and possibly linked with other undiscovered nickel-dependent enzymes. PMID:24710389

  9. Nutritional aspects of human lactation*

    PubMed Central

    Thomson, A. M.; Black, A. E.

    1975-01-01

    This paper reviews the literature on the incidence and duration of breast-feeding in various countries, the volume and composition of breast milk, the health and nutrition of breast-fed babies as judged by growth and morbidity, maternal nutritional requirements during lactation, and the effect of prolonged lactation on maternal health. It appears that lactation can be as well sustained by impoverished as by affluent mothers, and that even in communities where malnutrition is common the average growth of infants is satisfactory up to the age of about 3 months on a diet of breast milk alone. Breast milk appears to have specific anti-infective properties, but prolonged breast-feeding will not prevent infections among older infants reared in a poor environment. The authors believe that breast-feeding is the best form of nutrition for the young infant and deplore its decline in modern industrial societies. The recommendations of various FAO/WHO Expert Groups on nutritional intakes during lactation are summarized. The need for an increased daily energy intake of 4.2 MJ (1 000 kcal) is questioned, and an increase of 2.5 MJ (600 kcal) is suggested. Data on the effect of prolonged lactation on the health of the mother are scanty; body weight appears to be maintained even among poorly nourished mothers. The authors stress the need for well-planned and technically adequate studies of the material and psychological factors involved in breast feeding. PMID:816479

  10. Midtrimester abortion by ethacridine lactate.

    PubMed

    Goswami, B K; Raha, A; Gupta, A; Mukherjee, K

    1982-07-01

    This article discusses a clinical trial with the abortifacient agent ethacridine lactate as it was used for midtrimester abortion in Calcutta during the period January-July 1980. Results are then compared with intraamniotic hypertonic saline. 130 subjects were divided into 2 groups--Group 1 (60 women) were terminated with ethacridine lactate and group 2 (70 women) were terminated with saline. In cases where the patient complained of pain, analgesia was administered. In both groups, the largest concentration of women fell in the age groups 16-20 and 21-25. Similarly, single women were the largest representation in both groups although the saline group included more widows. Ethacridine lactate can be administered earlier in the 2nd trimester than saline. With it, expulsion occurred within 36 hours in 56.6% of the cases as compared with 22.9% in group 2. Both groups required the same amount of assistance with oxytocin. In group 1, there were only 3 cases (5%) of minor complications whereas in group 2, 19 cases (27.1%) developed complications. This alone strongly recommends ethacridine lactate as the preferred abortifacient. The success rate was 98%. Thus, ethacridine lactate appears to be a safe and effective agent for pregnancy termination during the 2nd trimester. PMID:7142727

  11. Isolation of human lactate dehydrogenase isoenzyme X by affinity chromatography.

    PubMed Central

    Kolk, A H; van Kuyk, L; Boettcher, B

    1978-01-01

    Human isoenzyme LDH-X (lactate dehydrogenase isoenzyme X) was isolated from seminal fluid of frozen semen samples by affinity chromatography by using oxamate-Sepharose and AMP-Sepharose. In the presence of 1.6 mM-NAD+, isoenzyme LDH-X does not bind to AMP-Sepharose, whereas the other lactate dehydrogenase isoenzymes do. This is the crucial point in the isolation of isoenzyme LDH-X from the other isoenzymes. The purified human isoenzyme LDH-X had a specific activity of 146 units/mg of protein. Images Fig. 2. Fig. 3. PMID:213050

  12. Antipsychotics in pregnancy and lactation

    PubMed Central

    Babu, Girish N.; Desai, Geetha; Chandra, Prabha S.

    2015-01-01

    Research on psychotropic medications during pregnancy and lactation is limited as often involves complex ethical issues. Information on safety of psychotropic drugs during these critical phases is either inconclusive or undetermined. Many women with severe mental illness have unplanned pregnancies and require antipsychotic medication during pregnancy and lactation. Multiple issues have to be considered while choosing safe treatments for pregnant and lactating women and the best approach is to individualize the treatment. Medication should be guided primarily by its safety data and by the psychiatric history of the patient. Important issues to be kept in mind include pre-pregnancy counseling for all women, including planning pregnancies; folate supplementation, discussion with patient and family regarding options, and active liaison with obstetricians, ultrasonologists and pediatricians. Whenever possible, non-pharmacological approaches should be used in addition. PMID:26330648

  13. Lactational infertility in family planning.

    PubMed

    Short, R V

    1993-04-01

    The contraceptive effect of breast-feeding is the single most important determinant of human population growth rates in traditional societies without access to modern forms of contraception; lactational amenorrhoea is Nature's contraceptive. Even today, breast-feeding still prevents more pregnancies than all modern forms of contraception in many developing countries. Afferent neural inputs from the nipple pass via the spinal cord to the hypothalamus, where they cause a local release of beta endorphin. This acts to depress GnRH secretion, thereby inhibiting pituitary gonadotrophin secretion, ovarian follicular development, ovulation and menstruation. The hypothalamic beta endorphin release also inhibits dopamine production, resulting in increased pituitary prolactin secretion. The higher the suckling frequency, the more beta endorphin that is released and hence the longer the duration of lactational amenorrhoea. Lactational amenorrhoea can be relied up to give over 98% contraceptive protection to breast-feeding women in the first 6 months postpartum, regardless of their nutritional status or the time of first supplement introduction to the baby. This is because the first postpartum menstruation usually precedes the first ovulation during these early months. Once menstruation has resumed, lactation's contraceptive effect can no longer be relied upon, even though the woman continues to breast-feed. In breast-feeding women whose amenorrhoea extends beyond 6 months, there is an increasing tendency for the first ovulation to precede the first menstruation, thereby decreasing the reliability of lactational amenorrhoea as a contraceptive. Nevertheless, many women who continue to breast-feed may still have up to 1-2 years of good contraceptive protection from prolonged lactational amenorrhoea.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8489757

  14. 21 CFR 582.5311 - Ferrous lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5311 Ferrous lactate. (a) Product. Ferrous lactate. (b) Conditions of use. This...

  15. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... prepared by reacting calcium lactate or sodium lactate with ferrous sulfate, direct reaction of lactic acid.... (1996), pp. 154 to 155, which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1...

  16. 21 CFR 184.1311 - Ferrous lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... reacting calcium lactate or sodium lactate with ferrous sulfate, direct reaction of lactic acid with iron... to 155, which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part...

  17. Is lactation nature's contraceptive? Data from Samoa.

    PubMed

    Fitzgerald, M H

    1992-01-01

    Data from a Samoan menstruation study suggest that lactation, even intensive on-demand lactation, does not inhibit menstruation or conception. This paper explores the applied and theoretical implications of continuing to accept lactation as a universally effective fertility control mechanism. Such thinking can have disastrous implications for family planning programs, and it keeps us from challenging long-held assumptions about lactation's role in population growth in early populations. PMID:1514124

  18. 21 CFR 582.1207 - Calcium lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium lactate. 582.1207 Section 582.1207 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1207 Calcium lactate. (a) Product. Calcium lactate. (b) Conditions of use. This substance...

  19. The origin and evolution of lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence of mammary glands are the defining morphological feature of mammals, and a successful lactation is crucial to mammalian reproductive strategies. Among mammalian species, the nature of lactation and the composition of milk vary greatly. The evolution of lactation and its diversity amon...

  20. 200th anniversary of lactate research in muscle.

    PubMed

    Gladden, L Bruce

    2008-07-01

    This year, 2008, marks the bicentennial of research into lactate metabolism in muscle. Berzelius linked lactate accumulation to exercise in 1807/1808 when he noted the presence of lactate in the muscles of "hunted stags." Today, the exact mechanism of intramuscular lactate oxidation and the relationship of lactate dehydrogenase to mitochondria remain unresolved as animated debate surrounds the intracellular lactate shuttle. PMID:18580290

  1. Composition, coagulation properties, and cheesemaking potential of milk from cows undergoing extended lactations in a pasture-based dairying system.

    PubMed

    Auldist, M J; Grainger, C; Houlihan, A V; Mayes, J J; Williams, R P W

    2010-04-01

    Extending the lactation length of dairy cows beyond the traditional 10 mo toward lactations of up to 22 mo has attracted interest in the pasture-based seasonal dairying systems of Australia and New Zealand as a way of alleviating the need for cows to conceive during peak lactation, such as is required to maintain seasonally concentrated calving systems. Lactation lengths longer than 10 mo instead provide cows with more time to cycle and conceive after parturition and may therefore be more suitable systems for high-producing Holstein-Friesian cows. Before recommending such systems there is a need to evaluate the effects of long lactations on the suitability of milk for manufacture of high-quality dairy products. In the current experiment, the composition of milk from cows entering the second half of a 22-mo lactation was examined in detail and compared with that from cows undergoing a traditional 10-mo lactation. On 2 occasions, coagulation properties were measured using low amplitude strain oscillation rheometry, and Cheddar cheese was made in 250-L pilot-scale vats. Results showed that milk from extended lactations had higher concentrations of fat and protein than cows undergoing 10-mo lactations under similar management conditions and at the same time of year. The ratio of casein to true protein was not affected by lactation length and neither were the proportions of individual caseins. The increase in milk solids during extended lactations translated into a more rapid rate of coagulation and ultimately a firmer curd on one of the two occasions. Milk from extended lactations yielded more cheese per 100 kg of milk, and there were few differences in the composition or organoleptic properties of the cheese. These data are the first to show that pasture-based dairy industries could embrace the use of extended lactations without compromising the core business of producing high-quality dairy products. PMID:20338417

  2. Point of Care Measurement of Lactate.

    PubMed

    Di Mauro, Francesca Miranda; Schoeffler, Gretchen Lee

    2016-03-01

    Lactate is generated as a consequence of anaerobic glycolysis by all tissues of the body. Increased l-lactate, the isoform produced by most mammals, reflects increased anaerobic metabolism secondary to tissue hypoperfusion or tissue hypoxia in most clinical situations, and is called type A lactic acidosis. The utility of lactate measurement and serial lactate monitoring in veterinary patients has been demonstrated in multiple studies. Blood lactate concentration is significantly elevated in many disease processes including septic peritonitis, immune-mediated hemolytic anemia, Babesiosis, trauma, gastric dilation and volvulus, and intracranial disease. Lactate clearance can be used to assess response to fluid therapy, cardiovascular therapeutics, and blood product transfusion in patients affected by type A lactic acidosis. Lactate concentration in peritoneal, pericardial, and synovial fluid can also be used as a diagnostic tool. Point of care analyzers such as the Lactate Pro, Lactate Scout, Accutrend, iSTAT, and Lactate Plus have been shown to be accurate lactate measurement instruments in small animal patients. PMID:27451047

  3. Evolution of D-lactate dehydrogenase activity from glycerol dehydrogenase and its utility for D-lactate production from lignocellulose.

    PubMed

    Wang, Qingzhao; Ingram, Lonnie O; Shanmugam, K T

    2011-11-22

    Lactic acid, an attractive, renewable chemical for production of biobased plastics (polylactic acid, PLA), is currently commercially produced from food-based sources of sugar. Pure optical isomers of lactate needed for PLA are typically produced by microbial fermentation of sugars at temperatures below 40 °C. Bacillus coagulans produces L(+)-lactate as a primary fermentation product and grows optimally at 50 °C and pH 5, conditions that are optimal for activity of commercial fungal cellulases. This strain was engineered to produce D(-)-lactate by deleting the native ldh (L-lactate dehydrogenase) and alsS (acetolactate synthase) genes to impede anaerobic growth, followed by growth-based selection to isolate suppressor mutants that restored growth. One of these, strain QZ19, produced about 90 g L(-1) of optically pure D(-)-lactic acid from glucose in < 48 h. The new source of D-lactate dehydrogenase (D-LDH) activity was identified as a mutated form of glycerol dehydrogenase (GlyDH; D121N and F245S) that was produced at high levels as a result of a third mutation (insertion sequence). Although the native GlyDH had no detectable activity with pyruvate, the mutated GlyDH had a D-LDH specific activity of 0.8 μmoles min(-1) (mg protein)(-1). By using QZ19 for simultaneous saccharification and fermentation of cellulose to D-lactate (50 °C and pH 5.0), the cellulase usage could be reduced to 1/3 that required for equivalent fermentations by mesophilic lactic acid bacteria. Together, the native B. coagulans and the QZ19 derivative can be used to produce either L(+) or D(-) optical isomers of lactic acid (respectively) at high titers and yields from nonfood carbohydrates. PMID:22065761

  4. Bladder cancer cells re-educate TAMs through lactate shuttling in the microfluidic cancer microenvironment

    PubMed Central

    Liu, Pengfei; Cao, Yanwei; Wang, Yonghua; Yang, Xuecheng; Xu, Xiaodong; Wang, Xinsheng; Niu, Haitao

    2015-01-01

    Background In the present study, we aimed to investigate the influence of lactate shuttling on the functional polarization and spatial distribution of transitional cell carcinoma of the bladder (TCCB) cells and macrophages. Methods We designed a microfluidic coculture chip for real-time integrative assays. The effect of lactate shuttling on the re-education of macrophages by TCCB cells was explored by measuring the levels of NO using a total NO assay kit and by evaluating the protein expression of iNOS, p-NFkB-p65, Arg-1 and HIF-1α via cell immunofluorescence and western blotting. Additionally, we examined TCCB cell viability using acridine orange/ethidium bromide (AO/EB) and MitoTracker staining. Moreover, the concentration distributions of lactate and large signaling proteins in the culture chambers were measured using 4′,6-diamidino-2-phenylindole (DAPI) and fluorescein isothiocyanate-dextran (FITC-dextran). Furthermore, the recruitment of macrophages and the influence of macrophages on BC metastasis were observed via light microscopy. Results We confirmed that TCCB cells reprogrammed macrophages into an M2 phenotype. Moreover, lactate inhibited M1 polarization and induced M2 polarization of macrophages, but blockade of cancer cell-macrophage lactate flux significantly inhibited the re-education of macrophages by TCCB cells. In addition, lactate diffused faster and deeper than large signaling proteins in the microfluidic tumor microenvironment. Furthermore, lactate alone induced the migration of macrophages, and M1, but not M2, macrophages reduced the motility of TCCB cells. Conclusions TCCB cells reprogrammed macrophages into an M2 phenotype in a manner that depended on cancer cell-TAM lactate flux. Furthermore, the lactate shuttle may be a determinant of the density of TAMs in tumor tissue. PMID:26474279

  5. Relationship among blood indicators of lipomobilization and hepatic function during early lactation in high-yielding dairy cows

    PubMed Central

    Muiño, Rodrigo; Pereira, Víctor; Campos, Rómulo; Benedito, José Luis

    2011-01-01

    Blood indicators are used as a tool to diagnose metabolic disorders. The present work was conducted to study the relationships among blood indicators of lipomobilization and hepatic function in high-yielding dairy cows. Two groups of Holstein cows were studied: 27 early lactation cows and 14 mid lactation cows from four different herds with similar husbandry characteristics in Galicia, Spain. Blood samples were obtained to measure beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), triglycerides (TG), and the activity of aspartate transaminase (AST) and gamma-glutamyl transferase. Cows in early lactation had higher levels of BHB and NEFA than mid lactation cows. High lipomobilization (NEFA > 400 µmol/L) was detected in 67% and 7% of early lactation and mid lactation cows, respectively, while subclinical ketosis (BHB > 1.2 mmol/L) was detected in 41% and 28% of the early lactation and lactation cows, respectively. TG concentrations were low in all cows suffering subclinical ketosis and in 61% of the cows with high lipomobilization. During early lactation, 30% of cows suffered hepatic lipidosis as detected by levels of AST. Compromised hepatic function was observed in early lactation cows as shown by lower concentrations of glucose, total protein, and urea. PMID:21897097

  6. Developmental regulation of mitochondrial biogenesis and function in the mouse mammary gland during a prolonged lactation cycle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The regulation of mitochondrial biogenesis and function in the lactating mammary cell is poorly understood. The goal of this study was to use proteomics to relate temporal changes in mammary cell mitochondrial function during lactation to changes in the proteins that make up this organelle. The hypo...

  7. Lactate metabolism by pediococci isolated from cheese.

    PubMed

    Thomas, T D; McKay, L L; Morris, H A

    1985-04-01

    Pediococcus pentosaceus is commonly found among the adventitious microflora of Cheddar cheese. When this organism was incubated with L-(+)-lactate under anaerobic conditions, L-(+)-lactate was rapidly converted to D-(-)-lactate until racemic (DL) lactate was present. Under aerobic conditions this initial reaction was followed by a slower reaction resulting in the use of both lactate isomers and in the production of acetate and CO2. With intact cells the lactate oxidation system had an optimum pH of 5 to 6, depending on the initial lactate concentration. Cells grown anaerobically possessed lactate-oxidizing activity which increased two- to fourfold as sugar was exhausted from the medium. Aerobic growth further increased specific activities. Cheddar cheese was made with the deliberate addition of P. pentosaceus. When the resulting cheese was grated to expose a large surface area to O2, lactate was converted to acetate at a rate which depended on the density of pediococci in the cheese. The lactate oxidation system remained active in cheese which had been ripened for 6 months. PMID:4004222

  8. Is lactate an undervalued functional component of fermented food products?

    PubMed Central

    Garrote, Graciela L.; Abraham, Analía G.; Rumbo, Martín

    2015-01-01

    Although it has been traditionally regarded as an intermediate of carbon metabolism and major component of fermented dairy products contributing to organoleptic and antimicrobial properties of food, there is evidence gathered in recent years that lactate has bioactive properties that may be responsible of broader properties of functional foods. Lactate can regulate critical functions of several key players of the immune system such as macrophages and dendritic cells, being able to modulate inflammatory activation of epithelial cells as well. Intraluminal levels of lactate derived from fermentative metabolism of lactobacilli have been shown to modulate inflammatory environment in intestinal mucosa. The molecular mechanisms responsible to these functions, including histone deacetylase dependent-modulation of gene expression and signaling through G-protein coupled receptors have started to be described. Since lactate is a major fermentation product of several bacterial families with probiotic properties, we here propose that it may contribute to some of the properties attributed to these microorganisms and in a larger view, to the properties of food products fermented by lactic acid bacteria. PMID:26150815

  9. Decreasing lactate level and increasing antibody production in Chinese Hamster Ovary cells (CHO) by reducing the expression of lactate dehydrogenase and pyruvate dehydrogenase kinases.

    PubMed

    Zhou, Meixia; Crawford, Yongping; Ng, Domingos; Tung, Jack; Pynn, Abigail F J; Meier, Angela; Yuk, Inn H; Vijayasankaran, Natarajan; Leach, Kimberly; Joly, John; Snedecor, Bradley; Shen, Amy

    2011-04-20

    Large-scale fed-batch cell culture processes of CHO cells are the standard platform for the clinical and commercial production of monoclonal antibodies. Lactate is one of the major by-products of CHO fed-batch culture. In pH-controlled bioreactors, accumulation of high levels of lactate is accompanied by high osmolality due to the addition of base to control pH of the cell culture medium, potentially leading to lower cell growth and lower therapeutic protein production during manufacturing. Lactate dehydrogenase (LDH) is an enzyme that catalyzes the conversion of the substrate, pyruvate, into lactate and many factors including pyruvate concentration modulate LDH activity. Alternately, pyruvate can be converted to acetyl-CoA by pyruvate dehydrogenases (PDHs), to be metabolized in the TCA cycle. PDH activity is inhibited when phosphorylated by pyruvate dehydrogenase kinases (PDHKs). In this study, we knocked down the gene expression of lactate dehydrogenase A (LDHa) and PDHKs to investigate the effect on lactate metabolism and protein production. We found that LDHa and PDHKs can be successfully downregulated simultaneously using a single targeting vector carrying small inhibitory RNAs (siRNA) for LDHa and PDHKs. Moreover, our fed-batch shake flask evaluation data using siRNA-mediated LDHa/PDHKs knockdown clones showed that downregulating LDHa and PDHKs in CHO cells expressing a therapeutic monoclonal antibody reduced lactate production, increased specific productivity and volumetric antibody production by approximately 90%, 75% and 68%, respectively, without appreciable impact on cell growth. Similar trends of lower lactate level and higher antibody productivity on average in siRNA clones were also observed from evaluations performed in bioreactors. PMID:21392546

  10. Exogenous lactate supply affects lactate kinetics of rainbow trout, not swimming performance

    PubMed Central

    Omlin, Teye; Langevin, Karolanne

    2014-01-01

    Intense swimming causes circulatory lactate accumulation in rainbow trout because lactate disposal (Rd) is not stimulated as strongly as lactate appearance (Ra). This mismatch suggests that maximal Rd is limited by tissue capacity to metabolize lactate. This study uses exogenous lactate to investigate what constrains maximal Rd and minimal Ra. Our goals were to determine how exogenous lactate affects: 1) Ra and Rd of lactate under baseline conditions or during graded swimming, and 2) exercise performance (critical swimming speed, Ucrit) and energetics (cost of transport, COT). Results show that exogenous lactate allows swimming trout to boost maximal Rd lactate by 40% and reach impressive rates of 56 μmol·kg−1·min−1. This shows that the metabolic capacity of tissues for lactate disposal is not responsible for setting the highest Rd normally observed after intense swimming. Baseline endogenous Ra (resting in normoxic water) is not significantly reduced by exogenous lactate supply. Therefore, trout have an obligatory need to produce lactate, either as a fuel for oxidative tissues and/or from organs relying on glycolysis. Exogenous lactate does not affect Ucrit or COT, probably because it acts as a substitute for glucose and lipids rather than extra fuel. We conclude that the observed 40% increase in Rd lactate is made possible by accelerating lactate entry into oxidative tissues via monocarboxylate transporters (MCTs). This observation together with the weak expression of MCTs and the phenomenon of white muscle lactate retention show that lactate metabolism of rainbow trout is significantly constrained by transmembrane transport. PMID:25121611

  11. Inflammatory mediators in mastitis and lactation insufficiency.

    PubMed

    Ingman, Wendy V; Glynn, Danielle J; Hutchinson, Mark R

    2014-07-01

    Mastitis is a common inflammatory disease during lactation that causes reduced milk supply. A growing body of evidence challenges the central role of pathogenic bacteria in mastitis, with disease severity associated with markers of inflammation rather than infection. Inflammation in the mammary gland may be triggered by microbe-associated molecular patterns (MAMPs) as well as danger-associated molecular patterns (DAMPs) binding to pattern recognition receptors such as the toll-like receptors (TLRs) on the surface of mammary epithelial cells and local immune cell populations. Activation of the TLR4 signalling pathway and downstream nuclear factor kappa B (NFkB) is critical to mediating local mammary gland inflammation and systemic immune responses in mouse models of mastitis. However, activation of NFkB also induces epithelial cell apoptosis and reduced milk protein synthesis, suggesting that inflammatory mediators activated during mastitis promote partial involution. Perturbed milk flow, maternal stress and genetic predisposition are significant risk factors for mastitis, and could lead to a heightened TLR4-mediated inflammatory response, resulting in increased susceptibility and severity of mastitis disease in the context of low MAMP abundance. Therefore, heightened host inflammatory signalling may act in concert with pathogenic or commensal bacterial species to cause both the inflammation associated with mastitis and lactation insufficiency. Here, we present an alternate paradigm to the widely held notion that breast inflammation is driven principally by infectious bacterial pathogens, and suggest there may be other therapeutic strategies, apart from the currently utilised antimicrobial agents, that could be employed to prevent and treat mastitis in women. PMID:24961655

  12. Inhibition of lactate transport in Ehrlich ascites tumor cells and human erythrocytes by a synthetic anhydride of lactic acid.

    PubMed

    Johnson, J H; Belt, J A; Dubinsky, W P; Zimniak, A; Racker, E

    1980-08-01

    The synthesis and some of the physical and biological characteristics of a new inhibitor of lactate transport are described. The inhibitor is isobutylcarbonyl lactayl anhydride (iBCLA). It is formed by the condensation of lactic acid and isobutylchloroformate. It inhibits lactate transport 50% at 0.5 microgram/mg of protein in both Ehrlich ascites tumor cells and human erythrocytes. In contrast, 15 microgram of iBCLA/mg of protein is required for 50% inhibition of phosphate transport in erythrocytes, and phosphate transport in Ehrlich ascites tumor cells is unaffected at levels as high as 50 microgram of iBCLA/mg of protein. A time-dependent and concentration-dependent reversal of lactate transport inhibition took place on exposure of iBCLA-treated Ehrlich ascites cells to hydroxylamine or dithiothreitol. These data, along with the observed sensitivity of the lactate transporter to sulfhydryl reagents [Spencer, T. L., & Lehninger, A. L. (1976) Biochem. J. 154, 405-414], suggest that iBCLA acylates an essential sulfhydryl group on the transporter. When glycolyzing Ehrlich ascites tumor cells were treated with concentrations of iBCLA sufficient for complete inhibition of lactate transport, intracellular lactate levels increased, intracellular pH and extra-cellular lactate levels decreased, and overall lactate production was inhibited. PMID:7407072

  13. 21 CFR 184.1207 - Calcium lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Calcium lactate. 184.1207 Section 184.1207 Food... Specific Substances Affirmed as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6H10CaO6.xH2O,...

  14. 21 CFR 184.1207 - Calcium lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium lactate. 184.1207 Section 184.1207 Food and... Substances Affirmed as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6H10CaO6.xH2O, where x is any... calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications of the Food...

  15. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS Reg. No. 996-31-6) is the potassium salt of lactic acid. It is a hydroscopic, white, odorless solid and...

  16. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food... GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS Reg. No. 996-31-6) is the potassium salt of lactic acid. It is a hydroscopic, white, odorless solid and is prepared commercially...

  17. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium lactate. 184.1639 Section 184.1639 Food... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS Reg. No. 996-31-6) is the potassium salt of lactic acid. It is a hydroscopic, white, odorless solid and...

  18. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS Reg. No. 996-31-6) is the potassium salt of lactic acid. It is a hydroscopic, white, odorless solid and...

  19. 21 CFR 184.1639 - Potassium lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Potassium lactate. 184.1639 Section 184.1639 Food... Specific Substances Affirmed as GRAS § 184.1639 Potassium lactate. (a) Potassium lactate (C3H5O3K, CAS Reg. No. 996-31-6) is the potassium salt of lactic acid. It is a hydroscopic, white, odorless solid and...

  20. 21 CFR 184.1207 - Calcium lactate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium lactate. 184.1207 Section 184.1207 Food... GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6H10CaO6.xH2O, where x is any integer up to 5, CAS Reg. No. 814-80-2) is prepared commercially by the neutralization of lactic acid with...

  1. 21 CFR 184.1207 - Calcium lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Calcium lactate. 184.1207 Section 184.1207 Food... Specific Substances Affirmed as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6H10CaO6.xH2O, where... lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications...

  2. 21 CFR 184.1207 - Calcium lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Calcium lactate. 184.1207 Section 184.1207 Food... Specific Substances Affirmed as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6H10CaO6.xH2O, where... lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient meets the specifications...

  3. Cerebral Lactate Metabolism After Traumatic Brain Injury.

    PubMed

    Patet, Camille; Suys, Tamarah; Carteron, Laurent; Oddo, Mauro

    2016-04-01

    Cerebral energy dysfunction has emerged as an important determinant of prognosis following traumatic brain injury (TBI). A number of studies using cerebral microdialysis, positron emission tomography, and jugular bulb oximetry to explore cerebral metabolism in patients with TBI have demonstrated a critical decrease in the availability of the main energy substrate of brain cells (i.e., glucose). Energy dysfunction induces adaptations of cerebral metabolism that include the utilization of alternative energy resources that the brain constitutively has, such as lactate. Two decades of experimental and human investigations have convincingly shown that lactate stands as a major actor of cerebral metabolism. Glutamate-induced activation of glycolysis stimulates lactate production from glucose in astrocytes, with subsequent lactate transfer to neurons (astrocyte-neuron lactate shuttle). Lactate is not only used as an extra energy substrate but also acts as a signaling molecule and regulator of systemic and brain glucose use in the cerebral circulation. In animal models of brain injury (e.g., TBI, stroke), supplementation with exogenous lactate exerts significant neuroprotection. Here, we summarize the main clinical studies showing the pivotal role of lactate and cerebral lactate metabolism after TBI. We also review pilot interventional studies that examined exogenous lactate supplementation in patients with TBI and found hypertonic lactate infusions had several beneficial properties on the injured brain, including decrease of brain edema, improvement of neuroenergetics via a "cerebral glucose-sparing effect," and increase of cerebral blood flow. Hypertonic lactate represents a promising area of therapeutic investigation; however, larger studies are needed to further examine mechanisms of action and impact on outcome. PMID:26898683

  4. 21 CFR 184.1768 - Sodium lactate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium lactate. 184.1768 Section 184.1768 Food and... Substances Affirmed as GRAS § 184.1768 Sodium lactate. (a) Sodium lactate (C3H5O3Na, CAS Reg. No. 72-17-3) is the sodium salt of lactic acid. It is prepared commercially by the neutralization of lactic acid...

  5. 21 CFR 184.1768 - Sodium lactate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium lactate. 184.1768 Section 184.1768 Food and... Substances Affirmed as GRAS § 184.1768 Sodium lactate. (a) Sodium lactate (C3H5O3Na, CAS Reg. No. 72-17-3) is the sodium salt of lactic acid. It is prepared commercially by the neutralization of lactic acid...

  6. 21 CFR 184.1768 - Sodium lactate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium lactate. 184.1768 Section 184.1768 Food and... Substances Affirmed as GRAS § 184.1768 Sodium lactate. (a) Sodium lactate (C3H5O3Na, CAS Reg. No. 72-17-3) is the sodium salt of lactic acid. It is prepared commercially by the neutralization of lactic acid...

  7. 21 CFR 184.1768 - Sodium lactate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium lactate. 184.1768 Section 184.1768 Food and... Substances Affirmed as GRAS § 184.1768 Sodium lactate. (a) Sodium lactate (C3H5O3Na, CAS Reg. No. 72-17-3) is the sodium salt of lactic acid. It is prepared commercially by the neutralization of lactic acid...

  8. Several insulin-like growth factor-I analogues and complexes of insulin-like growth factors-I and -II with insulin-like growth factor-binding protein-3 fail to mimic the effect of growth hormone upon lactation in the rat.

    PubMed

    Flint, D J; Tonner, E; Beattie, J; Gardner, M

    1994-02-01

    Lactation was suppressed in rats using a combined treatment of bromocriptine (to reduce prolactin concentrations) and a specific antiserum to rat GH administered twice daily for 2 days. When milk production had ceased, as determined by litter weight loss and the absence of milk in the stomachs of pups, attempts were made to reinitiate lactation using prolactin, GH, insulin-like growth factor-I (IGF-I) precomplexed to recombinant human IGF-binding protein-3 (hIGFBP-3) or IGF-I plus IGF-II precomplexed to hIGFBP-3. Despite the fact that all treatments except prolactin led to increases in serum IGFs and IGFBP-3, only prolactin and GH provoked the reinitiation of milk production as determined by increased litter weight gain, milk in the stomach of pups and a significant increase in the weight of the mammary glands. Since the mammary gland has been shown to produce IGFBPs which may inhibit IGF action we also tested three IGF-I analogues, R3-IGF-I, Long-IGF-I and Long-R3-IGF-I. R3-IGF-I has a single amino acid substitution (Glu to Arg) at position 3 whereas Long-IGF-I has a 13 amino acid N-terminal extension. These modifications dramatically reduce the ability of these analogues to bind to IGFBPs although they remain active at the IGF-I receptor. Such IGF analogues would therefore be expected to be active irrespective of the production of inhibitory IGFBPs. However, none was effective in reinitiating lactation, even at doses which have been shown to be biologically effective in terms of nitrogen retention.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7513341

  9. Lactation amenorrhea in Saudi women.

    PubMed Central

    Madani, K A; Khashoggi, R H; al-Nowaisser, A A; Nasrat, H A; Khalil, M H

    1994-01-01

    STUDY OBJECTIVE--The study aimed to investigate some aspects of breast feeding, namely-lactation amenorrhea, the average interval between pregnancies, and the extent of knowledge that an average Saudi woman has about breast feeding. DESIGN--This was a cross sectional study in which a pretested questionnaire was used to collect the information. SETTING--The study was conducted in the Taif area between January and April of 1990. Seventy nine primary health care centres participated. PARTICIPANTS--Altogether 1019 of 2400 women contacted who agreed to participate and met the criteria were studied. Eligible subjects were defined as Saudi women, between 16 and 40 years old, who came with their infants for vaccination, and had delivered between one week and 12 months previously. Each mother had at least one other child. MEASUREMENT AND MAIN RESULT--At birth, the percentage of infants who were initially breast fed was 98% but within three days of delivery over two thirds (68.9%) of the mothers gave other supplementary liquids to their infants. At the time of interview more than half (55.1%) of mothers had lactation amenorrhea. The mean (SD) lactation amenorrhea period and birth interval were 5.95 (5) and 26.8 (14.1) months, respectively. Mothers obtained information on breast feeding mainly from their doctors and television. Within families, husbands had the primary role in encouraging their wives to breast feed, followed by the mother and then by the mother in law. It was found that a high percentage (94.2%) of women had breast fed their previous child. CONCLUSION--The lack of adequate information on breast feeding and the short interval between births are local problems which should be considered by the health authorities. PMID:8051529

  10. Hemichannel-mediated release of lactate.

    PubMed

    Karagiannis, Anastassios; Sylantyev, Sergiy; Hadjihambi, Anna; Hosford, Patrick S; Kasparov, Sergey; Gourine, Alexander V

    2016-07-01

    In the central nervous system lactate contributes to the extracellular pool of readily available energy substrates and may also function as a signaling molecule which mediates communication between glial cells and neurons. Monocarboxylate transporters are believed to provide the main pathway for lactate transport across the membranes. Here we tested the hypothesis that lactate could also be released via opening of pannexin and/or functional connexin hemichannels. In acute slices prepared from the brainstem, hippocampus, hypothalamus and cortex of adult rats, enzymatic amperometric biosensors detected significant tonic lactate release inhibited by compounds, which block pannexin/connexin hemichannels and facilitated by lowering extracellular [Ca(2+)] or increased PCO2 Enhanced lactate release triggered by hypoxia was reduced by ∼50% by either connexin or monocarboxylate transporter blockers. Stimulation of Schaffer collateral fibers triggered lactate release in CA1 area of the hippocampus, which was facilitated in conditions of low extracellular [Ca(2+)], markedly reduced by blockade of connexin hemichannels and abolished by lactate dehydrogenase inhibitor oxamate. These results indicate that lactate transport across the membranes may occur via mechanisms other than monocarboxylate transporters. In the central nervous system, hemichannels may function as a conduit of lactate release, and this mechanism is recruited during hypoxia and periods of enhanced neuronal activity. PMID:26661210