The antioxidative and antilipidemic effects of different molecular weight chitosans in metabolic syndrome model rats.
The effect of high and low molecular weight chitosans (HMC; 1000 kDa, LMC; 30 kDa) on oxidative stress and hypercholesterolemia was investigated using male 6-week-old Wistar Kyoto rats as a normal model (Normal-rats) and spontaneously hypertensive rat/ND mcr-cp (SHP/ND) as a metabolic syndrome model (MS-rats), respectively. In Normal-rats, the ingestion of both chitosans over a 4 week period resulted in a significant decrease in total body weight (BW), glucose (Gl), triglyceride (TG), low density lipoprotein (LDL) and serum creatinine (Cre) levels. The ingestion of both chitosans also resulted in a lowered ratio of oxidized to reduced albumin and an increase in total plasma antioxidant activity. In addition to similar results in Normal-rats, the ingestion of only HMC over a 4 week period resulted in a significant decrease in total cholesterol levels in MS-rats. Further, the ingestion of LMC resulted in a significantly higher antioxidant activity than was observed for HMC in both rat models. In in vitro studies, LMC caused a significantly higher reduction in the levels of two stable radicals, compared to HMC, and the effect was both dose- and time-dependent. The findings also show that LDL showed strong binding in the case of HMC. These results suggest that LMC has a high antioxidant activity as well as antilipidemic effects, while HMC results in a significant reduction in the levels of pro-oxidants such as LDL in the gastrointestinal tract, thereby inhibiting the subsequent development of oxidative stress in the systemic circulation in metabolic model rats.
Fukuyama University, Japan.
Makoto
M
Anraku
Akihiro
A
Michihara
Taira
T
Yasufuku
Kenji
K
Akasaki
Daiju
D
Tsuchiya
Hiroaki
H
Nishio
Toru
T
Maruyama
Masaki
M
Otagiri
Yuji
Y
Maezaki
Yuko
Y
Kondo
Hisao
H
Tomida
D000418:Albumins / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use*; D001786:Blood Glucose / Q000378:metabolism*; D001835:Body Weight / Q000187:drug effects; D048271:Chitosan / Q000494:pharmacology / Q000627:therapeutic use*; D002784:Cholesterol / Q000097:blood* / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism*; D003404:Creatinine / Q000097:blood; D019587:Dietary Supplements; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005609:Free Radicals / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000378:metabolism; D000960:Hypolipidemic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D024821:Metabolic Syndrome / Q000188:drug therapy* / Q000378:metabolism; D008970:Molecular Weight; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D017382:Reactive Oxygen Species / Q000097:blood / Q000378:metabolism; D012016:Reference Values; D014280:Triglycerides / Q000097:blood
D000418:Albumins; D000975:Antioxidants; D001786:Blood Glucose; D008078:Cholesterol, LDL; D005609:Free Radicals; D000960:Hypolipidemic Agents; D017382:Reactive Oxygen Species; D014280:Triglycerides; D048271:Chitosan; D002784:Cholesterol; D003404:Creatinine