Conservative management of gynecologic diseases: insulin sensitizing agents in polycystic ovary syndrome

Gene substitution effect of bovine heat shock protein beta-1 gene polymorphism on age at calving in Indian dairy cattle

The study was planned with objective to screen single nucleotide polymorphisms (SNPs) in bovine HSPB1 gene and to find its effect on age at calving in Karan-Fries (Bos taurus × Bos indicus) and Sahiwal (Bos indicus) breeds of cattle. Genomic DNA was extracted from whole blood of 180 cows of both breeds. Based on publically available bovine HSPB1 gene sequence, one primer set was used for polymerase chain reaction amplification of the target region. Further DNA sequencing revealed a transition of thymine to cytosine at SNP rs208395876 in 5’UTR and a silent transversion of guanine to thymine at SNP rs723061520 in first coding sequence of bovine HSPB1 gene in both the studied breeds. Effect of individual SNP genotypes of bovine HSPB1 gene with age at calving (months) was analyzed separately in both breeds via regression using a repeated gene substitution MIXED model and least-squares means.The overall observed heterozygosity in both breeds and the F-Statistics values indicated that there was lesser genetic diversity in studied genomic region of bovine HSPB1 gene in Bos indicus compared to crossbred cattle. Association analysis revealed that SNP rs208395876 significantly delayed age at calving in Karan-Fries cows. In conclusion, the studied genomic region of bovine HSPB1 gene is polymorphic. In addition, these polymorphisms were informative with regard to age at calving of crossbred cows. Therefore, this gene is an important candidate for cow fertility.

Global Transcriptional Profiling of Granulosa Cells from Polycystic Ovary Syndrome Patients: Comparative Analyses of Patients with or without History of Ovarian Hyperstimulation Syndrome Reveals Distinct Biomarkers and Pathways

Ovarian hyperstimulation syndrome (OHSS) is often a complication of polycystic ovarian syndrome (PCOS), the most frequent disorder of the endocrine system, which affects women in their reproductive years. The etiology of OHSS is multifactorial, though the factors involved are not apparent. In an attempt to unveil the molecular basis of OHSS, we conducted transcriptome analysis of total RNA extracted from granulosa cells from PCOS patients with a history of OHSS (n = 6) and compared them to those with no history of OHSS (n = 18). We identified 59 significantly dysregulated genes (48 down-regulated, 11 up-regulated) in the PCOS with OHSS group compared to the PCOS without OHSS group (p-value < 0.01, fold change >1.5). Functional, pathway and network analyses revealed genes involved in cellular development, inflammatory and immune response, cellular growth and proliferation (including DCN, VIM, LIFR, GRN, IL33, INSR, KLF2, FOXO1, VEGF, RDX, PLCL1, PAPPA, and ZFP36), and significant alterations in the PPAR, IL6, IL10, JAK/STAT and NF-κB signaling pathways. Array findings were validated using quantitative RT-PCR. To the best of our knowledge, this is the largest cohort of Saudi PCOS cases (with or without OHSS) to date that was analyzed using a transcriptomic approach. Our data demonstrate alterations in various gene networks and pathways that may be involved in the pathophysiology of OHSS. Further studies are warranted to confirm the findings.

The Synergism in Hormonal and Cellular Changes in Male Mice on Long Term High Fat Exposure

OBJECTIVE

To determine the hormonal changes that occur as a result of the long-term intake of a very-high-fat diet (VHFD) that leads to simultaneous changes in the islets of Langerhans and adipocyte cell size.

METHODS

Male mice were fed with a normal chow diet (ND, n = 15) and a VHFD (n = 30) for 2, 12, and 24 weeks. Body weight, food intake, caloric intake (fat [saturated and unsaturated], protein, and carbohydrate), hormone levels (leptin and insulin), and islet of Langerhans/adipocyte size were quantitatively recorded.

RESULTS

In VHFD-fed animals, body weight showed a significant percent increase within the first 12 weeks and then plateaued with time. VHFD-fed animals consumed significantly less food than ND at all time periods, indicating that it was the quality of food and not the quantity that caused this increase in body weight. Male mice on VHFD showed a significant increase in leptin and insulin levels, along with accompanying growth in islet and adipocyte size within the first 12 weeks, which plateaued as the mice aged. The increases in the islet and adipocyte size in VHFD-fed animals were similar to the analogous increases in hormonal levels (2 vs. 12 vs. 24 weeks). These results, therefore, suggest that in diet-induced obesity changes, shifts in hormonal levels works hand-in-hand with metabolic adjustments at the cellular level to combat the effect of fat.

CONCLUSION

Thus, mechanisms like hormonal resistance, changes in adiposity, islet size, and caloric intake with prolonged exposure to high fat are probably defensive mechanisms employed to protect against diabetes. In order to understand these complicated and nuanced effects of high fat and to comprehend the underlying mechanism associated with it, it is important to focus on long-term studies that emphasize the synergy between cellular and hormonal changes, in addition to an analysis of individual components.

Long-Term High Fat Diet Has a Profound Effect on Body Weight, Hormone Levels, and Estrous Cycle in Mice

Background

Obesity causes several health complications along with disruption of the reproductive system. The aim of the current study was to determine how long-term intake of very high fat diet (VHFD) changes the hormonal milieu, affecting the cellular morphology and reproductive cycle in female mice.

Material/Methods

Mice were fed on normal diet (ND) and VHFD for 2 weeks, 12 weeks, and 25–27 weeks. We assessed changes in body weight, food consumption, energy intake, cellular and tissue morphology, hormonal levels (leptin, insulin, and estradiol), and vaginal smears were performed at various time points to determine the length and cellularity at each stage of the estrous cycle.

Results

Mice fed on VHFD showed a significant increase in weight gain, reduction in food intake, and increase in energy intake compared to animals fed on ND, indicating that the caloric density of the diet is responsible for the differences in weight gain. Hormonal analysis showed hyperleptinemia, hyperinsulinemia, and increases in estrogen levels, along with increases in size of the islet of Langerhans and adipocytes. After 25–27 weeks, all animals fed on VHFD showed complete acyclicity; elongation of phases (e.g., diestrous), skipping of phases (e.g., metestrous), or a combination of both, indicating disruption in the reproductive cycle. Quantitative analysis showed that in the diestrous phase there was a 70% increase in cell count in VHFD compared to animals fed on ND.

Conclusions

The above results show that morphological and hormonal changes caused by VHFD probably act via negative feedback to the hypothalamic-pituitary axis to shut down reproduction, which has a direct effect on the estrous cycle, causing acyclicity in mice.

The effect of insulin signaling on female reproductive function independent of adiposity and hyperglycemia

Physiological states of insulin resistance such as obesity and diabetes have been linked to abnormalities in female reproductive function. However, it is difficult to distinguish the direct effects of impaired insulin signaling from those of adiposity or hyperglycemia because these conditions often coexist in human syndromes and animal models of insulin resistance. In this study, we used lean, normoglycemic mouse lines with differing degrees of hyperinsulinemia and insulin receptor (Insr) expression to dissect the effects of altered insulin signaling on female reproduction. All three mouse lines [Ttr-Insr(-/-), Insr(+/-), and Insr(+/+) (wild type)] are able to maintain fertility. However, the insulin-resistant and hyperinsulinemic mice demonstrate altered duration of estrous cycles as well as aberrant distribution and morphology of ovarian follicles. These effects appear to be independent of hyperandrogenism in the mice. Pregnancy studies indicate decreased success in early progression of gestation. In successful pregnancies, decreased embryo weights and increased placental calcification also implicate altered insulin signaling in later gestational effects. Thus, abnormal insulin signaling, independent of adipose tissue mass, adipokine expression levels, and hyperglycemia, can affect parameters of the female hypothalamic-pituitary-gonadal axis and pregnancy outcomes.