Therapeutic potential of (1 → 4)-linked glucuronoglucan from an edible brown mussel Perna indica: A promising candidate for anti-inflammatory and antidyslipidemic nutraceuticals.

The brown mussel, Perna indica (Kuriakose & Nair, 1976), family Mytilidae, is harvested along the southwest coast of India for its rich nutritional composition and therapeutic potential. This study highlights the role of PIP-1, a (1 → 4)-linked glucuronoglucan derived from Perna indica composed of repeating pyranose units of β-d-glucose (Glcp) and α-D-glucuronic acid (GlcAp), in alleviating chronic diseases. PIP-1 demonstrated potent anti-inflammatory activity by attenuating 5-lipoxygenase (5-LOX) and cyclooxygenases (COXs) (IC₅₀ ≤ 1.5 mg/mL), with preferential COX-2 selectivity and reduced nitric oxide levels (IC₅₀ 2.9 μg/mL) in lipopolysaccharide-induced macrophages. In vivo models demonstrated that PIP-1, at higher dose, significantly reduced acute paw edema (91 % within 5 h) induced by carrageenan and chronic paw edema (77 % within day 10) induced by formalin. PIP-1 exhibited a potent antihypercholesterolemic effect by inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase (IC₅₀ 0.86 mg/mL) and significantly reduced triglyceride levels by 8-54 % in Caco-2 cells. In vivo studies showed that PIP-1 reduced total cholesterol by 68 % and triglycerides by 25 % in dyslipidemic rats after 48 h of acute study. In chronic studies, reductions of 19 % in total cholesterol and 46 % in triglycerides were observed after 45 days. The therapeutic potential of PIP-1 largely stems from its electronegative groups, which increase its total polar surface area, thereby facilitating receptor interactions through Van der Waals forces and modulating key metabolic pathways. Given its notable anti-inflammatory and antidyslipidemic effects, PIP-1 presents a promising source for developing nutraceutical products designed to alleviate chronic ailments.