Molecular Mechanisms in the Etiology of Polycystic Ovary Syndrome (PCOS): A Multifaceted Hypothesis Towards the Disease with Potential Therapeutics

Among the premenopausal women, Polycystic Ovary Syndrome (PCOS) is the most prevalent endocrinopathy affecting the reproductive system and metabolic rhythms leading to disrupted menstrual cycle. Being heterogeneous in nature it is characterized by complex symptomology of oligomennorhoea, excess of androgens triggering masculine phenotypic appearance and/or multiple follicular ovaries. The etiology of this complex disorder remains somewhat doubtful and the researchers hypothesize multisystem links in the pathogenesis of this disease. In this review, we attempt to present several hypotheses that tend to contribute to the etiology of PCOS. Metabolic inflexibility, aberrant pattern of gonadotropin signaling along with the evolutionary, genetic and environmental factors have been discussed. Considered a lifelong endocrinological implication, no universal treatment is available for PCOS so far however; multiple drug therapy is often advised along with simple life style intervention is mainly advised to manage its cardinal symptoms. Here we aimed to present a summarized view of pathophysiological links of PCOS with potential therapeutic strategies.

VDR downregulation and promoter hypermethylation as one of the causes for triggering type 2 diabetes mellitus: Clinical and molecular studies

Background

Our present study was to investigate the methylation and Gene expression of the vitamin D receptor (VDR) gene in the causing T2DM and to determine the inflammatory biomarkers in exaggerating T2DM in Kashmiri population.

Methods

In this study, T2DM cases (n = 100) and controls (n = 100) of Kashmiri population were designed. Blood samples were taken from both groups, and serum vitamin D levels, inflammatory biomarkers (TNF-α, IL-6, IL-10, CRP, Leptin and adiponectin) were estimated by ELISA. By using methylation-specific PCR (MS-PCR) and RT-PCR, respectively, the levels of methylation and expression were measured after the extraction of DNA and RNA.

Results

Studies using RT-PCR demonstrated that patients with diabetes had a lower degree of VDR expression than control subjects (P > 0.05). The T2DM was shown to be strongly correlated with hypermethylation (p-value < 0.001, OR 2.9; 95%CI 1.6-5.54). When compared to control groups, T2DM patients' levels of vitamin D in their serum were considerably lower (p < 0.01). Pro-inflammatory mediators like TNF-α, CRP, IL-6, and leptin levels were discovered to be higher, and concentrations of anti-inflammatory mediators like IL-10 and adiponectin were observed to be lower in people with T2DM than in people without the condition (p < 0.05).

Conclusions

This study suggests the hypermethylation and down expression of VDR as one of the basis for causing T2DM in kashmiri individuals, exaggerated by enhanced degree of TNF-α, CRP, IL-6 and leptin and diminished concentration of IL-10 and adiponectin in T2DM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01266-6.

Metabolic and Genetic Association of Vitamin D with Calcium Signaling and Insulin Resistance

Various evidences have unveiled the significance of Vitamin D in diverse processes which include its action in prevention of immune dysfunction, cancer and cardiometabolic disorders. Studies have confirmed the function of VD in controlling the expression of approximately nine hundred genes including gene expression of insulin. VD insufficiency may be linked with the pathogenesis of diseases that are associated with insulin resistance (IR) including diabetes as well as obesity. Thus, VD lowers IR-related disorders such as inflammation and oxidative stress. This review provides an insight regarding the molecular mechanism manifesting, how insufficiency of VD may be connected with the IR and diabetes. It also discusses the effect of VD in maintaining the Ca2+ levels in beta cells of the pancreas and in the tissues that are responsive to insulin.

Lipase Immobilized on Poly(VP-co-HEMA) Hydrogel for Esterification Reaction

Lipase from Candida rugosa was immobilized by entrapment on poly(N-vinyl- 2-pyrrolidone-co-2-hydroxyethyl methacrylate) (poly[VP-co-HEMA]) hydrogel, and divinylbenzene was the crosslinking agent. The immobilized enzymes were used in the esterification reaction of oleic acid and butanol in hexane. The activities of the immobilized enzymes and the leaching ability of the enzyme from the support with respect to the different compositions of the hydrogels were investigated. The thermal, solvent, and storage stability of the immobilized lipases was also determined. Increasing the percentage of composition of VP from 0 to 90, which corresponds to the increase in the hydrophilicity of the hydrogels, increased the activity of the immobilized enzyme. Lipase immobilized on VP(%):HEMA(%) 90:10 exhibited the highest activity. Lipase immobilized on VP(%):HEMA(%) 50:50 showed the highest thermal, solvent, storage, and operational stability compared to lipase immobilized on other compositions of hydrogels as well as the native lipase.

A maturation-related differential phosphorylation of the plasma membrane proteins of the epididymal spermatozoa of the hamster by endogenous protein kinases

When the plasma membranes of caput and cauda epididymal spermatozoa of hamster were evaluated for their ability to undergo phosphorylation, a differential phosphorylation of the membrane proteins was observed. In the plasma membranes of the caput epididymal spermatozoa (immature), twelve proteins were phosphorylated (100, 76, 67, 65, 55, 52, 47, 42, 38, 32, 30, and 20 kD), whereas in the plasma membranes of cauda epididymal spermatozoa (mature), a differential phosphorylation pattern was observed with respect to the 94, 67, 52, and 47 kD proteins. The 94 kD protein was found to be phosphorylated and the 67 kD protein was found to be not phosphorylated in cauda spermatozoal plasma membrane (Cd SPM) in contrast to this protein in caput spermatozoal plasma membrane (Cpt SPM). The 52 and 47 kD proteins were also more intensely phosphorylated in Cd SPM than Cpt SPM. The 100 kilodalton protein, although present in both Cpt and Cd sperm plasma membranes, was found to be phosphorylated at the tyrosine residues only in the Cd SPM, as indicated by the Western blot using antiphosphotyrosine antibody. Further, a differential phosphorylation of the substrate proteins present in the Cpt and Cd SPM was seen when Mg2+ in the assay buffer was replaced by other divalent cations. For instance, Zn2+ stimulated the phosphorylation of an 85 kD protein in cauda SPM and not in the caput SPM and Ca2+ stimulated the phosphorylation of a 76 kD protein only in the cauda SPM. The phosphoproteins in both the plasma membranes were found to be phosphorylated predominantly at the tyrosine residue. The differential phosphorylation at a 100 kD protein at tyrosine in the Cd SPM (Western blot), which is absent in the immature Cpt SPM, also indicated that certain proteins in the hamster spermatozoa are phosphorylated in a maturation-specific manner.

Acrosome membrane associated protein kinase activity in hamster spermatozoa

Acrosomal membranes isolated from the caput and cauda epididymal spermatozoa of hamster exhibited protein kinase activity and the endogenous protein substrates that were phosphorylated in the acrosomal membranes of caput and cauda spermatozoa were not all the same. The kinase activity was identified as a cAMP independent type and the use of specific stimulators and inhibitors indicated that the activity was not due to casein kinase, protein kinase A or protein kinase C but due to a tyrosine specific protein kinase that was not inhibited by Genistein. Phosphotyrosine was identified as the predominant phosphorylated residue in the proteins.

31P NMR study of phosphorus containing metabolites in the uterus of hamster: changes during the estrous cycle and the effect of hormonal manipulation

Changes in the concentrations of phosphorus containing metabolites were monitored by 31P NMR in the uteri of hamsters during the estrous cycle. Concentrations of phosphocreatine (PCr) and ATP were significantly increased in estrus animals compared to diestrus animals. Concentrations of these metabolites were also increased in immature female hamsters and ovariectomized (OVX) adult hamsters treated with estradiol indicating that estradiol was responsible for this effect. However, the steroid hormones progesterone and testosterone did not increase the concentrations of the phosphorus containing metabolites. Further, immature female hamsters also following treatment with estradiol showed an initial decline in phosphomonoester (PME), PCr, ATP and inorganic phosphate but by 24 h of treatment the concentrations returned to control levels. The NMR study also revealed that the intracellular pH of the hamster uterus was around 7.4 all through the estrous cycle.

Synthesis and secretion of proteins by the human proliferative, secretory, decidual and hyperplastic endometrium

Human endometria were analysed for the synthesis and secretion of proteins following short term culture of human endometrial tissue in the presence of 35S-methionine. During the menstrual cycle secretory proteins of molecular weight (MW) 30, 35, 45, 50, 59, 74, 97 and 135 kDa showed increased synthesis during the proliferative phase. The synthesis of these proteins decreased in the secretory phase but the induction of a 26 kDa protein in the early secretory phase and a 28 kDa protein in the late secretory phase was observed. The synthesis of the above secretory proteins of the human endometrium was also confirmed by two dimensional gel electrophoresis. Further, the results demonstrated that the secretory protein profile of human decidual endometria and endometria exhibiting irregular ripening was identical to that of normal secretory phase endometria. But, endometria exhibiting hyperplasia, cystic glandular hyperplasia and adenomatous glandular hyperplasia presented similar secretory protein profiles which were identical with the secretory protein profile of normal proliferative phase endometrium. The present study confirms that a number of proteins are synthesised by the human endometrium during the normal menstrual cycle and during pregnancy. It also provides data for the first time on the proteins secreted by the endometria exhibiting irregular ripening, hyperplasia, cystic glandular hyperplasia and adenomatous glandular hyperplasia.

Secretory proteins of the hamster cervix, uterus and oviduct: the effects of estradiol, progesterone and testosterone on the proteins secreted into the medium

The present study was directed towards identification of proteins synthesized and secreted by the cervix, uterus and oviduct of immature hamsters and by the uterus of ovariectomized adult hamsters. Hamsters were treated with estradiol, progesterone or testosterone for 3 consecutive days after which the tissues were incubated in vitro and [35S]methionine labelled proteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The results demonstrate a great degree of similarity between the proteins synthesized and secreted by the cervix, uterus and oviduct of hamsters. Treatment of hamsters with estradiol consistently increased the synthesis of a 60 kDa protein in the cervix, uterus and oviduct. Further, estradiol also consistently suppressed the synthesis of a 14, 30 and 72 kDa protein in the uterus but not in the cervix and oviduct. In the cervix, in addition to the 60 kDa protein estradiol also induced the synthesis of two other proteins (a 38 and 56 kDa protein). Testosterone and progesterone did not induce or suppress the synthesis of the secretory proteins in the hamster cervix, uterus and oviduct. In hamster the 60 kDa protein could serve as a marker of gene expression following hormone action.

Haem disorder in modified myoglobins. Effect of reconstitution procedures

Apomyoglobin was reconstituted with deuterohaem derivatives under various conditions. The fraction of disordered component, which is characterized by a 180 degree rotation of the haem group, for the various preparations was determined by n.m.r. spectroscopy. By using the procedures described, it was shown that the fraction of disordered component is minimized if the reconstitution is carried out with high-spin ferric haem derivatives within an experimentally determined optimum pH range of 8-9.5. Use of low-spin derivatives in either the ferrous or ferric forms leads to substantial increases in the fraction of disordered form. Attempted removal of the disordered form by selective oxidation and chromatographic purification was not effective.