Active biomolecules from microalgae in IBD treatment

Inflammatory bowel disease (IBD) is a multifactorial idiopathic chronic inflammatory condition affecting the gut. Animal models are indispensable to study various aspect of IBD and to facilitate preclinical drug/therapy design to target specific components involved in IBD pathogenesis. Rodent model of colitis induced by intrarectal injection of 2,4 dinitrobenzensulfonic acid (DNBS), results in colon inflammation and ulceration similar to Crohn's disease patients and is widely used to study potential role of nutraceuticals in IBD therapy. Using DNBS rat, we studied possible beneficial effects of treatment with the blue-green algae Aphanizomenon flos aquae (AFA), rich in bioactive products, to prevent colonic inflammation. In our study AphaMax® an aqueous AFA extract, kindly supplied by Nutrigea Research s.r.l., rich in phycocyanins and phytochrome, (20,50 or 100 mg/kg/day) was administered for 14 starting 7 days before the day of the colitis induction. Body weight loss, stool consistency, rectal bleeding, colon weight/length, histopathology, myeloperoxidase activity (MPO), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression and pro-inflammatory cytokine levels were assessed. Evaluation of nuclear factor-?B (NF-?B) p65 protein levels and detection of oxidative and nitrosative stress markers were also performed. AphaMax® treatment significantly attenuated the severity of DNBS-induced colitis, as evidenced by less severe clinical signs (body weight loss diarrhea incidence, rectal bleeding), decreased of colon weight/length ratio, attenuation of the macroscopic and histological colonic damage and of the neutrophil infiltration. Aphamax treatment also reduced the levels of proinflammatory cytokines and down-regulated the expression of NF-?B p65, as well as the expression of the inducible proteins iNOS and COX-2 and the levels of reactive oxygen species and nitrite. Our results indicate the AphaMax® supplementation is able to reduce colon injury induced by DNBS in rats, mainly due to its anti-inflammatory and anti-oxidant effects, suggesting that AphaMax® could be a good candidate as a complementary drug in the treatment of IBD.