Anti‐Obesity Effects Exerted by <scp> <i>Achyranthes bidentata</i> </scp> Polysaccharides in Diet‐Induced Obese Mice

Obesity involves persistent inflammation, insulin resistance, and disturbances in gut microbiota. <i>Achyranthes bidentata</i>, a plant long used in Chinese medicine, contains polysaccharides with bioactive properties. This study investigates polysaccharides isolated from its water extract (ABPs) consisting of 41.83% Glucose, 40.75% Galacturonic Acid, 7.86% Arabinose, 6.11% Galactose and 3.45% Rhamnose, which were prepared. We showed that ABPs mitigated obesity, decreased insulin resistance, alleviated inflammation, and relieved hepatic damage in high-fat diet (HFD)-fed mice. Specifically, ABPs regulated glucose levels by downregulating <i>GLUT1</i> and upregulating <i>PGC-1α</i>, and significantly reduced the expression of key genes related to adipogenesis and metabolism (<i>PPARα</i>, <i>PPARγ</i>, <i>C/EBPα</i>, and <i>SOX4</i>) in obese mice. Subsequent studies revealed that ABPs could alter the gut microbiota profile and increase short-chain fatty acids (SCFAs) levels in mice on an HFD. Treatment with ABPs reduced the <i>Firmicutes</i>: <i>Bacteroidota</i> ratio and declined the abundances of intestinal bacteria including <i>Intestinimonas</i>, <i>Lachnospiraceae_unclassified</i> and <i>Oscillibacter</i>. ABPs supplementation significantly restored the diet-induced imbalance of SCFAs in HFD-fed mice, notably reversing the reduction in propionic acid. This suggests that ABPs exert obvious anti-obesity activities, by suppressing systematic inflammation, improving hepatic metabolism, while concurrently ameliorating gut microbiota dysregulation in obese mice.