The effects of angiotensin I-converting enzyme inhibitory Rice wine less peptides on blood pressure of spontaneously hypertensive rats

Rice wine lees peptide (RWLP) is a potent angiotensin I-converting enzyme (ACE) inhibitor identified via in vitro screening. This study evaluated its antihypertensive effects and potential mechanisms in spontaneously hypertensive rats (SHR). SHR received RWLP at 5, 15, and 25 mg/kg BW. During a 24-hour test, RWLP (25 mg/kg BW) significantly reduced SBP and DBP by 42.51 and 36.37 mmHg, respectively, peaking at 9 hours. After six weeks of continuous administration, SBP reductions were 28.80 mmHg (low dose), 39.86 mmHg (medium dose), and 37.50 mmHg (high dose). RWLP mitigated hypertension-induced kidney damage by enhancing glomerular filtration. It regulated blood pressure and vascular injury by inhibiting ACE activity, lowering angiotensin II (ANG-II) levels, and modulating the renin-angiotensin system. Additionally, RWLP downregulated ACE and CMA1 expression while enhancing ATP synthesis-related genes, improving hypertension-induced mitochondrial dysfunction. Overall, RWLP is a promising functional peptide for blood pressure control.