Effects of orlistat and its relationship with nitric oxide in the small intestinal mucosa.
Nitric oxide (NO) is known to be a messenger molecule that plays an important role in physiological and pathological conditions. It is synthesized by an enzyme called nitric oxide synthase (NOS). Inducible NOS (iNOS), one of the three isomers of NOS, has both protective and toxic properties. In this study, the role of NO has been evaluated by gastrointestinal symptoms induced by orlistat which is used in obesity treatment. Orlistat was given to Wistar rats with and without iNOS inhibition. The effects of orlistat and inhibition of NOS were studied. Glucose, urea, alanine transaminase (ALT), and gamma glutamil transpeptidase (GGT) were descreased after short- and long- term orlistat applications. Dexamethasone increased level of these enzymes. Cholesterol and triglyceride were increased in all experimental groups than the controls. This increment was more severe in animals received orlistat and dexamethasone together. Small intestinal tissue also were researched histologically and NADPH-diaphorase (NADPH-d) histochemistrically. Orlistat caused histological damages in brush border membranes, connective tissues of villi, and lymphocyte migration also increased. Dexamethasone treatment prevented these damages partially while orlistat increased the NOS distribution in the tissue sections. Dexamethasone, which is an iNOS inhibitor, decreased NADPH-d histochemistry. There was a similiar NOS distribution both in the control and orlistat+dexamethasone group. Hence, we concluded that long- term trials with orlistat and similar drugs are needed.
Caner
Metin
M
Cerrahpasa Medical Faculty, Department of General Surgery, Istanbul University, Turkey.
Dogruman
Husniye
H
Taşkin
Elif
E
Kandil
Asli
A
Demirci
Cihan
C
D000818:Animals; D002784:Cholesterol / Q000097:blood; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D007413:Intestinal Mucosa / Q000166:cytology / Q000187:drug effects*; D007421:Intestine, Small / Q000187:drug effects*; D007783:Lactones / Q000009:adverse effects / Q000494:pharmacology*; D009252:NADPH Dehydrogenase / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000077403:Orlistat; D051381:Rats; D017208:Rats, Wistar; D014280:Triglycerides / Q000097:blood
D007783:Lactones; D014280:Triglycerides; D003907:Dexamethasone; D000077403:Orlistat; D002784:Cholesterol; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D009252:NADPH Dehydrogenase