Alladi Ramakrishnan Hall

Insulin and impaired glucose metabolism: the atypical determinants of lymphocyte adherence

Madhulika Dixit

Department of Biotechnology, IIT Madras

Daily and optimal trafficking of circulating leukocytes from bone marrow to peripheral organs and back is paramount for immunity, tissue repair and homeostasis. In addition to the circadian control, the temporal and spatial redistribution of naïve lymphocytes as well as their functionality is intricately linked to whole body metabolism. This is evident from the fact that metabolic aberrations as seen during diabetes and obesity is strongly associated with chronic inflammation and consequent cardiovascular complications. Despite being the early responders to biochemical changes in blood, and being periodically exposed to altering levels of glucose and insulin upon fasting and feeding, it is unclear if feeding induced biochemical changes in blood have any impact on trafficking of circulating lymphocytes. In a recent study conducted on healthy men, we observed that oral feeding following over-night fasting, enhances the adhesive properties of quiescent circulating lymphocytes, in order to mediate their homing to injured blood vessels through a mechanism involving non-canonical insulin signalling. Intriguingly, the adhesive property of circulating lymphocytes was found to be compromised in individuals exhibiting impaired glucose metabolism. My talk will summarize our recent findings in this regard.