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Mallu, A. C. T.

Publications and source records attributed to Mallu, A. C. T..

2 recordsLinked to original sources

Nutritional Triggers of PCOS and NAFLD: A Comparative Analysis of Diets in Female C57BL/6J Mice

ObjectiveObesity is a key factor in the development of Polycystic Ovary Syndrome (PCOS) and Non- alcoholic fatty liver disease (NAFLD). Its relationship with reproductive health and metabolic disorders remains an area of interest. Here we aimed to study the effects of two different obesogenic diets in female C57BL/6J mice on their metabolic and reproductive function. MethodsFemale C57BL/6J mice were fed high-fat high-sugar (HFHS) (45% fat and 10% sugar) diet and High fat diet (60% fat) for 21 weeks to investigate the effects on metabolic health and reproductive health. Mice were assessed for body weight, abdominal circumference, glucose tolerance (OGTT) and estrous cyclicity. At the end of the study biochemical analysis was done on isolated serum and, histological assessment of organs including liver and ovarian tissue was done to score for cystic follicle development and steatosis respectively. ResultsMice on the HFHS diet did not gain weight but developed dyslipidaemia, abnormal liver enzyme levels and severe hepatic steatosis. They did not show impaired glucose tolerance and did not develop any PCOS-like ovarian morphology indicating hepatic metabolic disturbances without significant impact on reproductive health. In contrast, mice on the 60% high-fat diet (HFD) showed marginal increase in body weight and developed altered estrous cyclicity and PCOS-like ovarian morphology. They also exhibited impaired glucose tolerance and insulin resistance, confirming a metabolic disturbance associated with PCOS. These mice did not develop significant liver fibrosis, suggesting a more specific impact on the ovaries and glucose metabolism. Our findings suggest that diet composition plays a crucial role in determining the specific metabolic and reproductive outcomes in obesity-related disorders in females.

physiology↗

Oral glucose feeding enhances adherence of quiescent lymphocytes to fibronectin via non-canonical insulin signalling.

Impaired glucose metabolism is associated with chronic inflammation, aberrant immunity and anomalous leukocyte trafficking. Conversely, infusion of functional immune cells restores glucose metabolism. Despite being exposed to periodic alterations in blood insulin levels upon fasting and feeding, studies exploring the physiological effects of these hormonal changes on quiescent circulating lymphocytes are missing. Here we find that oral glucose load in healthy men and mice enhance adherence of circulating peripheral blood mononuclear cells (PBMCs) to fibronectin. This led to increased homing of post-load PBMCs to injured blood vessels. Cell culture based experiments on Jurkat-T cells and PBMCs demonstrated that insulin elicits these adhesive effects through a non-canonical signalling involving insulin growth factor-1 receptor (IGF-1R) and phospholipase C gamma-1 (PLC{gamma}-1) mediated activation of integrin {beta}1. Our findings point to the relevance of post-prandial insulin spikes in regulating homing of circulating T-cells to various organs for tissue repair and immunity. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=123 SRC="FIGDIR/small/464163v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@11edce6org.highwire.dtl.DTLVardef@1389835org.highwire.dtl.DTLVardef@90c96eorg.highwire.dtl.DTLVardef@1988a63_HPS_FORMAT_FIGEXP M_FIG Insulin mediates fibronectin adherence of lymphocytes through non-canonical signalling. Insulin mediates auto-phosphorylation of IGF-1 receptor at Tyr1135 leading to activation of PLC-{gamma}1 through Tyr783 phosphorylation, which in turn leads to the activation of integrin 1 through intracellular calcium to ultimately enhance adhesion of quiescent lymphocytes to fibronectin. C_FIG

physiology↗