Platycodon grandiflorum Attenuates Non-Alcoholic Fatty Liver Disease in Rats Through Regulating Inflammatory Response via PPARγ and TLR4/NF-κB Signaling Pathway

Non-alcoholic fatty liver disease (NAFLD) has been considered a main health concern worldwide, and Platycodon grandiflorum (PG) has been traditionally employed in ethnopharmacology for managing hepatic metabolic disorders. This study aimed to elucidate the potential effect of PG on NAFLD in rats, and furthermore, the mechanism was explored. PG supplementation significantly increased body weight, serum total cholesterol, triglycerides, and LDL-cholesterol levels in HFD-induced obese rats (p < 0.05). In addition, HFD-induced lipid accumulation and inflammatory response in the liver were also suppressed. Then, the factors contributing to the regulating effect of PG on NAFLD were estimated by using network pharmacology and RNA sequencing. Moreover, western blotting and reverse transcription quantitative polymerase chain reaction (RT-qPCR) suggested that PG treatment obviously downregulated the expression levels of nuclear factor-κB (NF-κB), Toll-like receptor 4 (TLR4), myeloid differentiation primary response protein 88 (MyD88), and inhibitor I kappa B alpha (IκBα), whereas it upregulated the expression of peroxisome proliferator-activated receptor-gamma (PPARγ). Taken together, these findings corroborated the modulatory capacity of PG on NAFLD rats through regulating inflammatory response via PPARγ and TLR4/NF-κB pathway.