Shenshuai Yingyang Jiaonang attenuates CKD-induced muscle atrophy: a role for Faecalibacterium prausnitzii and the EGFR/PI3K/AKT signaling axis.

BACKGROUND: The occurrence of muscle atrophy in chronic kidney disease (CKD) is a prevalent complication with serious consequences but lacks effective treatment. Modulating the gut microbiota offers a promising new therapeutic approach. Shenshuai Yingyang Jiaonang (SSYYJN) is a clinically validated prescription of traditional Chinese medicine for muscle atrophy in CKD, yet the molecular basis for its therapeutic action requires elucidation. PURPOSE: To evaluate the therapeutic efficacy of SSYYJN against CKD-induced muscle atrophy, investigate the mechanism from the perspective of the gut microbiota, and explore potential strategies for enhancing the treatment efficacy of SSYYJN. METHODS: A rat model of CKD with concomitant muscle atrophy was established by 5/6 nephrectomy. 16S rDNA sequencing and fecal microbiota transplantation (FMT) experiments were conducted to elucidate the gut microbiota's role in SSYYJN efficacy. Untargeted metabolomics profiling and the pharmacological network analysis were conducted to investigate the potential mechanism of Faecalibacterium prausnitzii (FP) probiotics on SSYYJN. The regulatory mechanism of SSYYJN in CKD-associated muscle atrophy was validated through in vitro C2C12 cell experiments. RESULTS: In patients with CKD-associated protein-energy wasting (PEW), effective SSYYJN treatment improved mid-arm muscle circumference, hand grip strength, mid-arm circumference, and serum albumin. Moreover, post-hoc microbiome analysis revealed that the abundance of FP was higher in treatment-responsive patients. In a CKD rat model, SSYYJN conferred protection against renal injury, malnutrition, and muscle atrophy, this therapeutic effect was related to the gut microbiota modulation. Of note, a higher abundance of FP was also observed in SSYYJN-treated CKD rats. Further analyses suggested that FP was associated with increased levels of carnosol and may enhance EGFR/PI3K/AKT signaling, thereby potentiating the therapeutic effect of SSYYJN against CKD-induced muscle atrophy. CONCLUSION: These findings suggest a gut microbiota-dependent mechanism underlying the action of SSYYJN against muscle atrophy in CKD. FP may be linked to the effects of SSYYJN, potentially involving the generation of carnosol and the upregulation of the EGFR/PI3K/AKT pathway, representing a targeted therapeutic strategy.