The Antioxidative and Antilipidemic Effects of Different Molecular Weight Chitosans in Metabolic Syndrome Model Rats

Abstract

The metabolic syndrome is a constellation of risk factors, including atherogenic dyslipidemia, impaired fasting glucose, hypertension, and central adiposity, predisposing to higher risks of oxidative stress, type 2 diabetes and atherosclerotic cardiovascular disease. [1][2][3][4] In particular, an enhancement in oxidative stress by reactive oxygen species (ROS) has been proposed as a common pathomechanism by which cardiovascular risk factors affect the vessel wall to induce and amplify vessel and organ injury. Thus, an appropriate evaluation and reduction in oxidative stress in the circulating blood is important from the viewpoint of protecting vascular endothelium and vascular smooth muscle cells against oxidative stress.5-7) Dietary modifications, which include the use of antilipidemic supplements, are one of the key elements in the management of these metabolic abnormalities. For example, chitosan has been proposed as a safe and efficacious dietary supplement that can contribute to weight loss by reducing the amount of dietary fat absorbed, thereby improving calorie balance. 8)Chitosan, a cationic polysaccharide produced by the Ndeacetylation of chitin under alkaline conditions, contains a linear sugar backbone, composed of b-1,4-linked glucosamine units. It exhibits a wide variety of biological activities except for cholesterol-lowering effects.9-11) A property of particular interest for this study is the antioxidant properties of chitosan. Santhosh et al. reported that the administration of chitosan to rats that had been treated with isoniazid or rifampicin inhibited the oxidation of hepatotoxic lipids.12) It had also been reported that chitosan, when injected, inhibited glycerol-induced renal oxidative damage in rats.13) Because of the numerous in vitro and in vivo antioxidant studies that have appeared, chitosan has attracted considerable attention from researchers. In spite of this, however, relationships between molecular weight (MW) and antioxidant activity have not been extensively investigated in in vivo studies.In this study, we examined the effect of high and low MW chitosan supplements (HMC; 1000 kDa and LMC; 30 kDa) on oxidative stress in normal and metabolic syndrome model rats, in an attempt to better understand the potential role for HMC and LMC as an antioxidant in the systemic circulation. Oxidative stress was evaluated by monitoring oxidized serum albumin levels, a sensitive marker for protein oxidation, in the systemic circulation.14,15) We also investigated the role of HMC and LMC as a chelator, to develop a better understanding of the mechanism of the antioxidant activity of HMC and LMC in metabolic syndrome model rats. MATERIALS AND METHODSMaterials LMC (MWϭ30 kDa) and HMC (MWϭ1000 kDa) were obtained from Nippon Kayaku Food Techno Co., Ltd. (Gunma, Japan). All other chemicals were of the highest grade available and were obtained from commercial sources.Animals and Treatment Male (6 weeks old) Wistar Kyoto rats as a normal model (Normal-rats) and spontaneously hypertensive rat/ND mcr-cp ...

Possible Synergistic Effect and Antioxidant Properties of Chitosan Nanoparticles and Quercetin against Carbon Tetrachloride-Induce Hepatotoxicity in Rats

“…These authors showed that, in addition to normalizing the oxidative stress markers, which is attributed to the antoxidant properties of chitosan, the normalization of plasma AST and ALT levels in β-chitosan and CCl 4 -treated rats indicates that β-chitosan may stabilize the cell membrane and may prevent a leakage of intracellular enzymes into the blood. Thus, the overall hepatoprotective effect of chitosan is probably due to a counteraction of free radicals by its antioxidant nature and/or to its ability to inhibit lipid accumulation by its antilipidemic property [95] [96]. Santhosh et al [97] showed that co-treatment with chitosan may prevent antitubercular drugs-induced hepatotoxicity in rats.…”

The Potential of Chitosan and Its Derivatives in Prevention and Treatment of Age-Related Diseases

“…There is an urgent need to elucidate the role of oxidative stress in aging and to find promising perspectives on the efficacy of modulating agents for oxidative stress in treatment or prevention of age-related diseases. Perspectives on application of chitosan and its derivatives in the treatment of oxidative stress in age-related diseases have been considered in a number of research papers [ 31 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ]. Researchers from Fukuyama University, Japan [ 43 ] concluded that chitosan has a direct antioxidant activity in systemic circulation by lowering the indices of oxidative stress in both in vitro and in vivo studies.…”

Hypolipidemic and anti‐inflammatory effects of aorta and heart tissues of cattle and pigs in the atherosclerosis rat model

“…However, recently, some substances from food or natural components have been reported to be effective against atherosclerosis and cardiovascular disease because of their antioxidant and anti‐inflammatory activities (Anraku et al . ; Zhao et al . ).…”