Electroacupuncture regulates the cross-talk between Islets and Peripancreatic Adipose tissue to combat obesity combined with insulin resistance

Abstract

Abstract Electroacupuncture plays a positive role in regulating glucolipid metabolism and is related to the coordination of sensory nerves. As a complex functional unit, the pancreas is crucial for the regulation of glucolipid metabolism throughout the body. In particular, the expandability of peripancreatic adipose tissue promotes the progression of obesity into type 2 diabetes mellitus. However, the changes in the response and interaction of pancreatic components to electroacupuncture remain to be determined. Here, We studied certain characteristics of obesity combined with insulin resistance using high-fat diet fed rats, and verified the functional changes and neuroplasticity changes in pancreatic components after electroacupuncture. We further compared the effects of different acupoints to optimize the scheme. Electroacupuncture (2 mA, 2/15 Hz) treatment was performed for 2 weeks after 4 weeks of high-fat diet feeding. In order to explore the hypoglycemic mechanism of Electroacupuncture and the specific pathway mediating the interaction between peripancreatic adipose tissue and pancreatic islets, we detected the expressions of transient receptor potential vanilloid 1 (TRPV1), calcitonin gene–related peptide (CGRP), insulin and other proteins in the pancreas and peripancreatic adipose tissue. The increased body weight, triglycerides, total cholesterol, serum glucose, and insulin levels in the model rats suggested the presence of obesity and insulin resistance. Electroacupuncture at ST25, LI11, or ST37 acupoints ameliorated the aforementioned symptoms to varying degrees, with electroacupuncture at ST25 being the most effective. Electroacupuncture resulted in increased activity of the TRPV1-CGRP-islet beta cell pathway, which led to reduced insulin secretion by pancreatic beta cells, and alleviation of metabolic stress in peripheral insulin-sensitive tissues. After chemically silencing TRPV1 sensory afferents, the observed effect disappeared, verifying that TRPV1 sensory afferents play a vital role in mediating electroacupuncture-mediated regulation of islet and peripancreatic adipose tissue function. Moreover, in TRPV1 knockout mice, the level of peripancreatic adipose tissue inflammation decreased, paralleling the recovery of islet beta cell function. Our study determined the interaction of electroacupuncture-mediated TRPV1 sensory afferents on peripancreatic adipose tissue and pancreatic islets, ultimately improving glucolipid metabolism, and the combined effect of electroacupuncture at ST25 was the most successful.