Tracer-based metabolomic technology to investigate the role and mechanism of Fangji Huangqi Tang in regulating lipid metabolism disorders in MPC-5 cells.

Lipid metabolism disturbances drive Nephrotic Syndrome (NS) progression. Current NS therapies have limited efficacy against lipid disorders and often cause significant side effects. Previously, our glucose tracer profiling revealed a compensatory activation of fatty acid synthesis in NS, highlighting lipid metabolism as a critical pathophysiological factor. However, the specific molecular targets through which the multi-component Fangji Huangqi Tang (FHT) regulates this process remain undefined. This study evaluated FHT's protective effects using an adriamycin (ADR)-induced MPC-5 podocyte injury model. We integrated an optimized 13C16-palmitic acid tracer platform with acylcarnitine-targeted metabolomics and molecular biology to dissect underlying mechanisms. FHT intervention significantly attenuated podocyte apoptosis and neutral lipid deposition while upregulating structural proteins. Crucially, it rescued mitochondrial dysfunction by restoring membrane potential, ATP levels, and cellular oxygen consumption. Metabolomic analysis demonstrated that FHT rebalanced lipid homeostasis by inhibiting triglyceride synthesis, promoting triglyceride catabolism, enhancing phospholipid synthesis, and restoring fatty acid oxidation. In conclusion, FHT mitigates podocyte injury by reshaping lipid metabolic homeostasis via multiple targets, providing a strong mechanistic basis for its clinical use in NS.