RESUMO
Background: Mucus derived from many land snails has been extensively utilised in medicine and cosmetics, but some biological activities of the mucus need to be well documented. Nevertheless, most mucus is obtained from land snails, while mucus from freshwater snails has yet to be attended. Methods: This study aims to determine and compare mucus's antioxidant and anti-inflammatory activities from the land snail Lissachatina fulica and the freshwater snail Pomacea canaliculata. ABTS, DPPH, reducing power and total antioxidant activity assays were used to evaluate the antioxidant capacity. Inhibition of nitric oxide production in lipopolysaccharide-activated RAW 264.7 cells was performed to determine the anti-inflammatory activity. Additionally, the histochemical analysis of mucous cells in each snail foot was conducted to compare the distribution of mucous cells and types of mucins using periodic acid-Schiff and Alcian blue staining. Results: Mucus from L. fulica and P. canaliculata exhibited antioxidant and anti-inflammatory activities in different parameters. L. fulica mucus has higher total antioxidant (44.71 ± 2.11 mg AAE/g) and nitric oxide inhibitory activities (IC50 = 9.67 ± 0.31 µg/ml), whereas P. canaliculata mucus has better-reducing power activity (43.63 ± 2.47 mg AAE/g) and protein denaturation inhibition (IC50 = 0.60 ± 0.03 mg/ml). Histochemically, both species' dorsal and ventral foot regions contained neutral and acid mucins in different quantities. In the dorsal region, the neutral mucins level in L. fulica (16.64 ± 3.46%) was significantly higher than that in P. canaliculata (11.19 ± 1.50%), while the acid mucins level showed no significant difference between species. Levels of both mucins in the ventral foot region of L. fulica (15.08 ± 3.97% and 10.76 ± 3.00%, respectively) were significantly higher than those of P. canaliculata (2.25 ± 0.48% and 2.71 ± 0.56%, respectively). This study revealed scientific evidence of the biological capacity of mucus from L. fulica and P. canaliculata as well as provided helpful information on the region of the foot which produces effective mucus.
Assuntos
Antioxidantes , Óxido Nítrico , Animais , Antioxidantes/farmacologia , Caramujos , MucoRESUMO
Because of the wide variety of cells which are arrayed in the tissue of the gastrointestinal tracts of these two fish, basic histological examination is not appropriate to clarify the histological structure. But histochemical techniques can be applied to identify the chemical differences contained in the tissues. The present study aimed to compare the histochemical characteristics of the gastrointestinal tracts of adult fishes which consume different types of food: the Nile tilapia is herbivore and the hybrid catfish is carnivore. The esophagus, stomach and intestine of each fish was stained with 1) Masson's trichrome, for the muscular and connective tissues, 2) Periodic acid Schiff, for neutral mucin, 3) Alcian blue pH 2.5 and pH 1.0, for acid and sulfated acid mucin. The neutral and acid mucins were observed in the esophagus of the tilapia and catfish but sulfated acid mucin was found only in the catfish. Both neutral and acid mucins presented in the stomach of the tilapia, whereas the stomach of the catfish contained only the neutral mucin although it is contained more collagen in the submucosa. The tilapia intestine revealed that neutral and acid mucins were presented throughout the tissue, and small amounts of sulfated acid mucin were observed in the anterior intestine. However, sulfated acid mucin was very obviously located in posterior intestine of the catfish. Moreover, all parts of the catfish intestine showed both neutral and acid mucins with a thick collagen layer in the submucosa. This research will be useful for understanding the physiology of the relevant digestive systems and making a diagnosis of some gastrointestinal diseases in these two fish.
