白芷多糖对2型糖尿病大鼠的降糖保肝作用

目的：研究白芷多糖(Angelica dahurica polysaccharide,ADP)的降糖保肝作用。方法：提取ADP，采用苯酚-硫酸法、硫酸-咔唑法、考马斯亮蓝法、高效凝胶渗透色谱法、高效液相色谱法分别测定中性糖质量分数、糖醛酸质量分数、蛋白质量分数、分子质量以及单糖组成。用高脂高糖联合链脲佐菌素(streptozotocin,STZ)诱导2型糖尿病(type 2 diabetes mellitus,T2DM)大鼠模型，分为空白对照组(Control组、灌喂蒸馏水)、模型组(Model组、灌喂蒸馏水)、ADP低剂量组(ADP-L组、灌喂200 mg/kg m_b ADP)、ADP高剂量组(ADP-H组、灌喂400 mg/kg m_b ADP)、阳性组(Positive组、灌喂200 mg/kg m_b二甲双胍)，连续灌胃4周，对T2DM大鼠体质量、空腹血糖(fasting blood sugar,FBG)值、葡萄糖耐量、空腹胰岛素(fasting insulin,FINS)水平、胰岛素抵抗指数(homeostatic...

Hypoglycemic and Hepatoprotective Effect of Angelica dahurica Polysaccharide in Type 2 Diabetic Rats

Purpose: To investigate the hypoglycemic and hepatoprotective effects of Angelica dahurica polysaccharide (ADP). Methods: The contents of neutral sugar, total glyoxylate and total protein, molecular mass and monosaccharide composition of ADP were determined by the phenol-sulfuric acid method, the sulfuric acid-carbazole method, the Coomassie brilliant blue method, high performance gel permeation chromatography (HPGPC) and high performance liquid chromatography (HPLC), respectively. Type 2 diabetes mellitus (T2DM) was induced in rats by high-fat and high-sucrose diet feeding combined with injection of streptozotocin (STZ). Five groups of rats were set up: blank control, model, low-dose ADP (200 mg/kg mb), high-dose ADP (400 mg/kg mb), and positive control (200 mg/kg mb metformin). The rats in the blank control and model groups were gavaged with distilled water. After four weeks of administration, body mass, fasting blood sugar (FBG), oral glucose tolerance test (OGTT), fasting insulin (FINS), homeostatic model assessment for insulin resistance (HOMA-IR) and glycogen levels were measured, hematoxylin-eosin (HE) staining was used to observe hepatic histopathological changes, and commercial kits were used to determine lipid metabolism, oxidative stress and liver function indexes. Results: ADP had the following composition: (83.26 ± 0.67)% neutral sugar, (8.32 ± 1.25)% glyoxylate, and (0.64 ± 0.07)% protein, and its molecular mass was 10.28 × 103 Da. Monosaccharide composition analysis showed that ADP consisted of rhamnose, arabinose, galactose, glucose, mannose, glucuronide acid and galacturonic acid with a molar ratio of 0.09:0.45:0.43:1.00:0.05:0.53:0.08. ADP significantly increased body mass, blood glucose, FINS and glycogen levels of T2DM rats (P < 0.01), significantly decreased FBG and HOMA-IR (P < 0.01), improved liver histopathology, and significantly improved lipid metabolism, oxidative stress and liver function indexes (P < 0.01). Conclusion: ADP has hypoglycemic and hepatoprotective effects, probably through regulating abnormal lipid metabolism and oxidative stress.