Anti-heart failure mechanism of saponin extract of black ginseng based on metabolomics

Objective: This study aimed to explore the mechanism of total saponin of black ginseng (TSBG) in treating heart failure (HF) in DOX-induced HF model rats.Methods: Rats with HF induced by the intraperitoneal injection of DOX were treated with TSBG (low dose, 30 mg/ kg/day; medium dose, 60 mg/kg/day; high dose, 120 mg/kg/day) and shakubar trivalsartan (80 mg/kg/day, positive control) for four weeks. Serum BNP and ANP levels were tested by ELISA, and pathological tissue sections were examined. Serum metabolites were measured using nontargeted metabolomic techniques. The expression of Akt/mTOR autophagy-associated proteins in heart tissue was detected using Western blot, including Beclin1, p62, LCII and LC3I.Results: Compared with the model group, rats in the TSBG-H group had a significantly lower heart index (p < 0.05), significantly lower serum levels of BNP (p < 0.01) and ANP (p < 0.01) and significantly fewer cardiac histopathological changes. Metabolomic results showed that TSBG significantly back-regulated 12 metabolites (p < 0.05), including cholesterol, histamine, sphinganine, putrescine, arachidonic acid, 3-sulfinoalanine, hypo-taurine, gluconic acid and lysoPC (18:0:0). These metabolite changes were involved in taurine and hypotaurine metabolism, arachidonic acid metabolism, sphingolipid metabolism, etc. The protein expression level of p-Akt/ Akt and p-mTOR/mTOR was significantly up-regulated (p < 0.001), whereas that of Beclin1, p62 (p < 0.001) and LCII/LC3I was down-regulated (p < 0.05).Conclusion: TSBG has an excellent therapeutic effect on DOX-induced HF in rats, probably by regulating the Akt/ mTOR autophagy signalling pathway, resulting in the improvement of taurine and hypotaurine metabolism, arachidonic acid metabolism and sphingolipid metabolism, which may provide a reference for elucidating the potential mechanism of action of TSBG against HF.