Mussel (Mytilus Galloprovincialis) By-Product Protein Attenuates Hypertension, Renal Dysfunction, and Metabolic Disturbances in Obese Rats

Abstract

Obesity is associated with an increased risk of arterial hypertension and renal dysfunction, but the protective value of aquaculture by-product proteins remains poorly documented. This study evaluated the effects of a protein concentrate extracted from by-products of the Mediterranean mussel Mytilus galloprovincialis on blood pressure and renal function in Wistar rats made obese through high-fat feeding. Twenty-four male rats were allocated to three groups (n = 8): Control, Obese (high-fat diet containing 35% fat for 13 weeks), and Treated obese (mussel protein supplementation for 4 weeks). The high-fat diet induced marked hypertension (systolic blood pressure: 169.5 ± 10.2 vs 117.3 ± 2.3 mmHg), cardiac and aortic hypertrophy, glomerular hyperfiltration, elevated proteinuria and microalbuminuria, and an increased vascular resistance index. Mussel protein supplementation reduced systolic blood pressure by 25%, normalized heart and aorta weight, corrected the hyperfiltration, and significantly reduced proteinuria and urinary uric acid relative to the untreated obese group (p < 0.05). The protein concentrate was compositionally standardized, containing 80.40 ± 0.32% crude protein (N × 6.25) and a complete essential amino acid profile (85.21 ± 1.32 g amino acids/100 g protein), with glutamic acid, glycine, aspartic acid, taurine, and leucine as the predominant residues. Proteins extracted from M. galloprovincialis by-products thus exert a cardiovascular and renal protective effect in the obese rat, plausibly linked to their amino acid and taurine content, supporting the development of this concentrate as a standardized nutraceutical or dietary supplement ingredient, in line with circular economy principles.