Mechanism of the Traditional Chinese Medicine Simiao Biejia Decoction Improves the Diabetes Mellitus-Induced Erectile Dysfunction in Rats.

OBJECTIVE: Simiao Biejia (SMBJ) granules, a traditional Chinese herbal remedy, have been used to treat erectile dysfunction caused by diabetes mellitus (DMED). However, the molecular mechanisms underlying SMBJ's therapeutic effects remain unclear. This study aimed to investigate the effects and mechanisms of SMBJ in a rat model of DMED using network pharmacology, proteomics, and molecular docking. METHODS: A rat model of DMED was established, and SMBJ granules were administered (0, 7.1, 14.2, and 28.4 mg/kg/d, respectively) for 4 weeks. Erectile function was evaluated by measuring intracavernous pressure and mean arterial pressure. The active compounds in SMBJ were analyzed by gas chromatography and identified using network pharmacology and bioinformatics. Potential targets in the penile tissue was identified via proteomics and validated by Western blotting. Molecular docking was used to assess the binding affinity between bioactive compounds and primary targets. RESULTS: SMBJ significantly improves erectile function and ameliorates DMED in rats by reducing corpus cavernosum fibrosis, decreasing eNOS and nNOS levels, alleviating oxidative stress in penile tissue, and mitigating damage to smooth muscle cells (SMCs) and vascular endothelial cells (VECs). Network pharmacology and proteomics identified 24 potential SMBJ targets in DMED. The 4 drug molecules identified were involved in the therapeutic effects of SMBJ, among which luteolin was predicted to be the core drug component. Luteolin bound directly with AKT1, a key differentially expressed protein in the penile tissue of DMED rats. Further analysis showed that luteolin in SMBJ activates the PI3K/Akt pathway and regulation of nNOS and NF-kB expression in the penile tissue of DMED rats to improve erectile function. CONCLUSION: SMBJ improved oxidative stress damage, vascular endothelial repair, and angiogenesis in the penile tissue of DMED rats. Luteolin is one of the core drug components of SMBJ in DMED treatment that regulates PI3K/AKT-related pathways.