Prolactin and thyroid stimulating hormone affecting the pattern of LH/FSH secretion in patients with polycystic ovary syndrome: A hospital-based study from North East India

Introduction: Polycystic ovary syndrome (PCOS) is one of the most important endocrinal diseases in reproductive age group, clinically manifested by hyperandrogenism and anovulation and different other metabolic disturbances that may have important implications for long-term health. Aim and Objective: The aim of this study was to determine the incidence of abnormal luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio in women with polycystic ovary and to assess the influence of prolactin and thyroid-stimulating hormone (TSH) in the elevated LH/FSH ratio. Study Design: Retrospective observational study. Materials and Methods: Eighty-five women in reproductive age diagnosed with PCOS between June 2012 to June 2014 at the Department of Obstetrics and Gynecology in a tertiary care hospital were selected for the study. Serum LH and FSH levels were determined and LH/FHS ratio (normal range ≤2) calculated in the study subjects. They underwent a detailed clinical, hormonal, and metabolic evaluation, which was performed between the second and third days of a natural or induced menstrual period. Results: Elevated LH/FSH ratio was found in 60 women (70.58%). Normal gonadotropin ratio was detected in 25 women (29.41%). Statistically significant differences in serum TSH levels were noted between groups with normal and elevated LH/FSH ratio. However, no statistically significant difference was noted in other endocrine parameters. Further analysis revealed a slight negative correlation of TSH with prolactin in the study subjects of PCOS with an 'r' value of − 0.3. Conclusions: LH/FSH ratio is one of the characteristic attribute of PCOS women. In the present study, this abnormality was detected in 70% of patients. Hypothyroidism was a common endocrinal abnormality and prolactin was inversely correlated to TSH levels in PCOS patients

A key GPCR phosphorylation motif discovered in arrestin2⋅CCR5 phosphopeptide complexes

The two non-visual arrestins, arrestin2 and arrestin3, bind hundreds of GPCRs with different phosphorylation patterns, leading to distinct functional outcomes. Structural information on these interactions is available only for very few GPCRs. Here, we have characterized the interactions between the phosphorylated human CC chemokine receptor 5 (CCR5) and arrestin2. We identified several new CCR5 phosphorylation sites necessary for stable arrestin2 complex formation. Structures of arrestin2 in the apo form and complexes with CCR5 C-terminal phosphopeptides, together with NMR, biochemical, and functional assays, revealed three phosphoresidues in a pXpp motif that are essential for arrestin2 binding and activation. The identified motif appears responsible for robust arrestin2 recruitment in many other GPCRs. An analysis of receptor sequences and available structural and functional information provides hints on the molecular basis of arrestin2/arrestin3 isoform specificity. Our findings demonstrate how multi-site phosphorylation controls GPCR⋅arrestin interactions and provide a framework to probe the intricate details of arrestin signaling