CURCUMIN RESTORES THE BALANCE OF NO-SYNTHASES IN THE BRAIN HEMISPHERES OF RATS EXPOSED TO ROUND-THE-CLOCK LIGHT UNDER CONDITIONS OF A DIET HIGH IN FRUCTOSE AND FAT

Abstract

The aim of the study was to evaluate the effect of curcumin on the ratio of constitutive and inducible NOS isoforms in the cerebral cortex of rats under a round-the-clock lighting (RCL) with a high fructose and fat diet. The experiments were performed on 21 white Wistar rats weighing 235±20 g, divided into 3 groups. Animals in the first group (control) received a standard diet (energy value 2720 kcal/kg) and were exposed to an equal alternation of light and darkness. The rats of the second and third groups were kept in RCL conditions against the background of the administration of a high-calorie carbohydrate-lipid diet (HCCLD, 4477 kcal/kg). In addition, animals of the third group received curcumin daily through a gavage, intragastrically, at a dose of 200 mg/kg. The activity of total NOS and its constitutive isoforms (cNOS) in the cerebral homogenate was measured, inducible isoenzyme (iNOS) activity and cNOS coupling index were calculated. Curcumin administration significantly reduced the total and inducible activity of NOS in the cerebral homogenate– by 34 and 38%, respectively, compared with the values of the second group. At the same time, cNOS activity (2.3-fold) and its coupling index (3.8-fold) increased significantly compared with the data of the second group. It is concluded that the use of curcumin in metabolic disorders associated with pathogenic factors of the “Western lifestyle” – light disorders and the use of HCCLD restores the normal ratio of constitutive and inducible NOS isoforms, cNOS coupling in the rat cerebral hemispheres, which prevents the development of oxidative-nitrosative stress.