Biochemistry Laboratory, Faculty of Sciences of Sfax, Sfax, Tunisia.
Int J Biol Macromol. 2011 Nov 1;49(4):742-6. doi: 10.1016/j.ijbiomac.2011.07.007. Epub 2011 Jul 19.
This study aims to examine the effects of polysaccharide levan on oxidative stress and hyperglycemia in alloxan-induced diabetic rats. Levan, used in this study, was a microbial levan synthetisized by a non pathogenic bacteria recently isolated and identified as Bacillus licheniformis. Animals were allocated into four groups of six rats each: a control group (Control), diabetic group (Diab.), normal rats received levan (L) and diabetic rats fed with levan (DL). Treated diabetic rats were administrated with levan in drinking water through oral gavage for 60 days. The administration of polysaccharide levan in diabetic rats caused a significant increase in glycogen level by 52% and a decrease in glucose level in plasma by 52%. Similarly, the administration of polysaccharide levan in diabetic rats caused a decrease in the thiobarbituric acid-reactive substances (TBARS) by 31%, 41%, 39% and 25%, an increase in superoxide dismutase (SOD) by 40%, 50%, 44% and 34%, and in catalase (CAT) by 18%, 20%, 12% and 18% in liver, kidney, pancreas and heart, respectively. Furthermore, a significant decrease in hepatic and renal indices toxicity was observed, i.e. alkalines phosphatases (ALP), aspartate and lactate transaminases (AST and ALT) activities, total bilirubin, creatinine and urea levels by 19%, 31%, 32%, 36%, 37% and 23%, respectively. The results show that administration of polysaccharide levan can restore abnormal oxidative indice near normal levels. This study demonstrates, for the first time, that polysaccharide levan is efficient in inhibiting hyperglycemia and oxidative stress induced by diabetes and suggests that levan supplemented to diet may be helpful in preventing diabetic complications in adult rats.
本研究旨在探讨多糖蔗果聚糖对四氧嘧啶诱导的糖尿病大鼠氧化应激和高血糖的影响。本研究中使用的蔗果聚糖是一种由最近分离并鉴定为地衣芽孢杆菌的非致病性细菌合成的微生物蔗果聚糖。动物被分为四组，每组六只大鼠：对照组（Control）、糖尿病组（Diab.）、正常大鼠给予蔗果聚糖（L）和糖尿病大鼠给予蔗果聚糖（DL）。治疗糖尿病大鼠通过口服灌胃在饮用水中给予蔗果聚糖 60 天。在糖尿病大鼠中给予多糖蔗果聚糖可使肝糖原水平显著增加 52%，使血浆葡萄糖水平降低 52%。同样，在糖尿病大鼠中给予多糖蔗果聚糖可使丙二醛（TBARS）降低 31%、41%、39%和 25%，超氧化物歧化酶（SOD）增加 40%、50%、44%和 34%，过氧化氢酶（CAT）分别增加 18%、20%、12%和 18%，在肝、肾、胰腺和心脏中。此外，观察到肝和肾毒性指标碱性磷酸酶（ALP）、天冬氨酸和乳酸转氨酶（AST 和 ALT）活性、总胆红素、肌酐和尿素水平显著降低，分别降低 19%、31%、32%、36%、37%和 23%。结果表明，给予多糖蔗果聚糖可使异常氧化指标恢复正常水平。本研究首次表明，多糖蔗果聚糖能有效抑制糖尿病引起的高血糖和氧化应激，并提示膳食中补充蔗果聚糖可能有助于预防成年大鼠的糖尿病并发症。
