Arthrospira platensis prevents impairment of intestinal smooth muscle relaxation in diet-induced obesity via modulation of nitric oxide, prostanoid and oxidative stress pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Arthrospira platensis (Spirulina) has been traditionally consumed in Africa, Asia and Central America as a nutrient-rich restorative food associated with metabolic balance and gastrointestinal health. Its longstanding ethnopharmacological use suggests biological activities related to antioxidant and anti-inflammatory effects, which are relevant in conditions associated with metabolic disorders.

AIM OF THE STUDY: This study investigated whether A. platensis supplementation prevents the reduction in ileal relaxant reactivity induced by a hypercaloric diet (HCD) in rats and explored the involvement of prostanoid, nitric oxide and NADPH oxidase pathways in this response.

MATERIALS AND

METHODS

Male Wistar rats were fed standard or hypercaloric diets for eight weeks and treated with A. platensis (25 mg kg-1·day-1). Isolated ileum segments were subjected to cumulative concentration-response curves to verapamil in the absence or presence of indomethacin, tempol, L-NAME, 1400W, apocynin or combined L-NAME plus apocynin. Relaxant reactivity was assessed by maximal effect and potency parameters.

RESULTS

The hypercaloric diet markedly reduced verapamil-induced relaxant potency, whereas A. platensis supplementation completely prevented this dysfunction without altering responses in healthy animals. In HCD-fed rats, indomethacin, tempol, L-NAME, 1400W and apocynin each fully restored relaxant potency, demonstrating the contribution of prostanoid overactivity, oxidative stress, excessive iNOS-derived nitric oxide and NADPH oxidase-dependent reactive oxygen species to the observed impairment. In supplemented animals, relaxant responses were fully or partially preserved across all pharmacological conditions.

CONCLUSIONS

These findings provide mechanistic support for the traditional use of A. platensis, demonstrating that its protective effects on intestinal smooth muscle function are mediated by the modulation of convergent inflammatory and redox pathways. The results highlight A. platensis as an ethnopharmacologically relevant natural product with potential for preventing obesity-associated gastrointestinal dysmotility.