Gestational Diabetes Is Characterized by Reduced Mitochondrial Protein Expression and Altered Calcium Signaling Proteins in Skeletal Muscle

The rising prevalence of gestational diabetes mellitus (GDM) affects up to 18% of pregnant women with immediate and long-term metabolic consequences for both mother and infant. Abnormal glucose uptake and lipid oxidation are hallmark features of GDM prompting us to use an exploratory proteomics approach to investigate the cellular mechanisms underlying differences in skeletal muscle metabolism between obese pregnant women with GDM (OGDM) and obese pregnant women with normal glucose tolerance (ONGT). Functional validation was performed in a second cohort of obese OGDM and ONGT pregnant women. Quantitative proteomic analysis in rectus abdominus skeletal muscle tissue collected at delivery revealed reduced protein content of mitochondrial complex I (C-I) subunits (NDUFS3, NDUFV2) and altered content of proteins involved in calcium homeostasis/signaling (calcineurin A, α1-syntrophin, annexin A4) in OGDM (n = 6) vs. ONGT (n = 6). Follow-up analyses showed reduced enzymatic activity of mitochondrial complexes C-I, C-III, and C-IV (−60–75%) in the OGDM (n = 8) compared with ONGT (n = 10) subjects, though no differences were observed for mitochondrial complex protein content. Upstream regulators of mitochondrial biogenesis and oxidative phosphorylation were not different between groups. However, AMPK phosphorylation was dramatically reduced by 75% in the OGDM women. These data suggest that GDM is associated with reduced skeletal muscle oxidative phosphorylation and disordered calcium homeostasis. These relationships deserve further attention as they may represent novel risk factors for development of GDM and may have implications on the effectiveness of physical activity interventions on both treatment strategies for GDM and for prevention of type 2 diabetes postpartum

Mechanical properties of the compass depressors of the sea-urchin Paracentrotus lividus (Echinodermata, Echinoidea) and the effects of enzymes, neurotransmitters and synthetic tensilin-like protein

The compass depressors (CDs) of the sea-urchin lantern are ligaments consisting mainly of discontinuous collagen fibrils associated with a small population of myocytes. They are mutable collagenous structures, which can change their mechanical properties rapidly and reversibly under nervous control. The aims of this investigation were to characterise the baseline (i.e. unmanipulated) static mechanical properties of the CDs of Paracentrotus lividus by means of creep tests and incremental force-extension tests, and to determine the effects on their mechanical behaviour of a range of agents. Under constant load the CDs exhibited a three-phase creep curve, the mean coefficient of viscosity being 561±365 MPa.s. The stress-strain curve showed toe, linear and yield regions; the mean strain at the toe-linear inflection was 0.86±0.61; the mean Young's modulus was 18.62±10.30 MPa; and the mean tensile strength was 8.14±5.73 MPa. Hyaluronidase from Streptomyces hyalurolyticus had no effect on creep behaviour, whilst chondroitinase ABC prolonged primary creep but had no effect on secondary creep or on any force-extension parameters; it thus appears that neither hyaluronic acid nor sulphated glycosaminoglycans have an interfibrillar load transfer function in the CD. Acetylcholine, the muscarinic agonists arecoline and methacholine, and the nicotinic agonists nicotine and 1-[1-(3,4-dimethyl-phenyl)-ethyl]-piperazine produced an abrupt increase in CD viscosity; the CDs were not differentially sensitive to muscarinic or nicotinic agonists. CDs showed either no, or no consistent, response to adrenaline, L-glutamic acid, 5-hydroxytryptamine and γ-aminobutyric acid. Synthetic echinoid tensilin-like protein had a weak and inconsistent stiffening effect, indicating that, in contrast to holothurian tensilins, the echinoid molecule may not be involved in the regulation of collagenous tissue tensility. We compare in detail the mechanical behaviour of the CD with that of mammalian tendon and highlight its potential as a model system for investigating poorly understood aspects of the ontogeny and phylogeny of vertebrate collagenous tissues.(undefined)info:eu-repo/semantics/publishedVersio

Safety and Efficacy of Dolutegravir in Treatment-Experienced Subjects With Raltegravir-Resistant HIV Type 1 Infection: 24-Week Results of the VIKING Study

Background. Dolutegravir (DTG; S/GSK1349572), a human immunodeficiency virus type 1 (HIV-1) integrase inhibitor, has limited cross-resistance to raltegravir (RAL) and elvitegravir in vitro. This phase IIb study assessed the activity of DTG in HIV-1–infected subjects with genotypic evidence of RAL resistance.Methods. Subjects received DTG 50 mg once daily (cohort I) or 50 mg twice daily (cohort II) while continuing a failing regimen (without RAL) through day 10, after which the background regimen was optimized, when feasible, for cohort I, and at least 1 fully active drug was mandated for cohort II. The primary efficacy end point was the proportion of subjects on day 11 in whom the plasma HIV-1 RNA load decreased by ≥0.7 log10 copies/mL from baseline or was <400 copies/mL.Results. A rapid antiviral response was observed. More subjects achieved the primary end point in cohort II (23 of 24 [96%]), compared with cohort I (21 of 27 [78%]) at day 11. At week 24, 41% and 75% of subjects had an HIV-1 RNA load of <50 copies/mL in cohorts I and II, respectively. Further integrase genotypic evolution was uncommon. Dolutegravir had a good, similar safety profile with each dosing regimen.Conclusion. Dolutegravir 50 mg twice daily with an optimized background provided greater and more durable benefit than the once-daily regimen. These data are the first clinical demonstration of the activity of any integrase inhibitor in subjects with HIV-1 resistant to RAL

EFFECTS OF INTRAINDIVIDUAL MATERNAL EXERCISE OR NO-EXERCISE ON PREGNANCY AND BIRTH OUTCOMES

Breanna D. Wisseman1, Christy Isler1, Edward R. Newton1, James DeVente1, Samantha McDonald, FACSM2, Cody Strom3, Linda E. May, FACSM1. 1East Carolina University, Greenville, NC. 2Illinois State University, Normal, IL. 3University of Southern Indiana, Evansville, IN. BACKGROUND: Although exercise during pregnancy is associated with improved maternal and fetal health, some have cited inherent differences in participants as a reason for improved outcomes. Therefore, the purpose of this analysis is to utilize the strength of a single-subject design to compare differences in pregnancy and birth outcomes between exercise or no exercise intervention. METHODS: This was a secondary analysis to examine pregnant women (n=7) who participated in a randomized controlled trial twice, once they were randomized to 150 minutes/week of exercise and another pregnancy to non-exercising control. Skinfolds were completed at 16- and 36-weeks’ gestation to estimate body fat percentage (BF%). Gestational age, diabetes (GDM) status, mode of delivery, weight gain (GWG), infant heart rate, sex, circumferences, weight, and length were collected via electronic birth records. Ponderal index (PI) and infant body mass index (iBMI) were calculated using standard formulas. RESULTS: Of the 7 women identified as participating in the study twice, 3 were randomized to control group first, while 4 were randomized to the exercise group first. There were no between-group differences in maternal skinfolds or GWG at 36-weeks. There were no differences between groups for BF% and both experienced an increase over time. There were no differences between groups for cases of GDM, mode of delivery, GWG, and infant sex. Although not significant, women tended to deliver closer to their due date in the exercise group. There were no between-group differences in infant heart rate; head, abdominal, or chest circumferences; reflexes; and Apgar scores at delivery. There were trends of higher PI (p= 0.13) and iBMI (p= 0.18) in the exercise-exposed infants relative to their non-exercise exposed siblings. Due to small sample size, there were no significant regression models related to exercise group and pregnancy or birth outcomes. CONCLUSION: Although this is a small sample, it further supports safe pregnancy and birth outcomes in the same women regardless of exercise or not during pregnancy. Furthermore, the potential increase in PI and iBMI of infants exposed to exercise in utero relative to their non-exposed siblings suggests further research is required regarding body compartments (i.e., bone and muscle mass). Thus, future research should examine the effect of maternal exercise on differences in offspring body composition outcomes between exercised and non-exercised siblings. FINANCIAL SUPPORT: This study was partially funded by the American Heart Association (AHA grant #15GRNT24470029) and East Carolina University

MCF-7 breast cancer cells transfected with protein kinase C-alpha exhibit altered expression of other protein kinase C isoforms and display a more aggressive neoplastic phenotype.

Increased protein kinase C (PKC) activity in malignant breast tissue and positive correlations between PKC activity and expression of a more aggressive phenotype in breast cancer cell lines suggest a role for this signal transduction pathway in the pathogenesis and/or progression of breast cancer. To examine the role of PKC in the progression of breast cancer, human MCF-7 breast cancer cells were transfected with PKC-alpha, and a group of heterogenous cells stably overexpressing PKC-alpha were isolated (MCF-7-PKC-alpha). MCF-7-PKC-alpha cells expressed fivefold higher levels of PKC-alpha as compared to parental or vector-transfected MCF-7 cells. MCF-7-PKC-alpha cells also displayed a substantial increase in endogenous expression of PKC-beta and decreases in expression of the novel delta- and eta-PKC isoforms. MCF-7-PKC-alpha cells displayed an enhanced proliferative rate, anchorage-independent growth, dramatic morphologic alterations including loss of an epithelioid appearance, and increased tumorigenicity in nude mice. MCF-7-PKC-alpha cells exhibited a significant reduction in estrogen receptor expression and decreases in estrogen-dependent gene expression. These findings suggest that the PKC pathway may modulate progression of breast cancer to a more aggressive neoplastic process

MCF-7 breast cancer cells transfected with protein kinase C-alpha exhibit altered expression of other protein kinase C isoforms and display a more aggressive neoplastic phenotype.

Increased protein kinase C (PKC) activity in malignant breast tissue and positive correlations between PKC activity and expression of a more aggressive phenotype in breast cancer cell lines suggest a role for this signal transduction pathway in the pathogenesis and/or progression of breast cancer. To examine the role of PKC in the progression of breast cancer human MCF-7 breast cancer cells were transfected with PKC-a and a group of heterogenous cells stably over expressing PKC-a were isolated (MCF-7-PKC- a).MCF-7-PKC-a cells expressed five fold higher levels of PKC-a as compared to parental or vector-transfected MCF- 7 cels. MCF-7-PKC-a cells also displayed a substantial increase in endogenous expression of PKC-8 and decreases in expression of the novel 6- and q-PKC isoforms. MCF-7-PKC-a cells displayed an enhanced proliferative rate anchorage-independent growth dramatic morphologic alterations including loss of an epithelioid appearance and increased tumorigenicity in nude mice. MCF-7-PKC- a cells exhibited a significant reduction in estrogen receptor expression and decreases in estrogen-dependent gene expression. These findings suggest that the PKC pathway may modulate progression of breast cancer to a more aggressive neoplastic process. Originally published Journal of Clinical Investigation Vol. 95 No. 4 Apr 199