Comparative analysis of the of red seaweed polysaccharides on hypertension–associated biomarkers in cadmium chloride-induced Wistar rats

Abstract

Red seaweeds, recognized for their diverse polysaccharide structures, exhibit significant therapeutic potential in modulating the renin-angiotensin-aldosterone system (RAAS) to mitigate hypertension, a major risk factor for cardiovascular diseases. This study investigates the antihypertensive properties of polysaccharides extracted from four Rhodophyta species: Gracilaria salicornia (GSP), Gracilaria edulis (GEP), Gelidiella acerosa (GAP), and Gelidium pusillum (GPP), using a cadmium chloride (CdCl₂)-induced hypertensive model in Wistar rats. GSP (100 mg/kg BW) significantly reduced hypertension-associated biomarkers, including angiotensin II (>65 %), C-reactive protein and myoglobin (>54 %), and troponin I and T (∼72 %), compared to GEP, GAP, and GPP in hypertensive rats (p < 0.05). GSP also improved serum levels of vitamin E (0.15 μg/mL) and nitric oxide (7.31 μg/mL), comparable to the telmisartan group, which restored vitamin E and nitric oxide to 0.24 μg/mL and 8.27 μg/mL, respectively. Antioxidant assays revealed a significant reduction in enzymatic antioxidant activity in CdCl₂-induced hypertensive rats relative to the healthy control group, with notable recovery upon GSP treatment. Histopathological evaluation indicated restored structural integrity of extracellular and cellular components in GSP-treated hypertensive rats, highlighting its potential to alleviate hypertension-induced oxidative stress.