Bhateja Pradeep Kumar, Kajal Anu, Singh Randhir
Department of Pharmacology, Bhojia Dental College and Hospitals, Bhud, Baddi, Himachal Pradesh, 173205, India.
Maharishi Markandeshwar (Deemed to Be University), Mullana, Ambala, 133207, Haryana, India.
J Ayurveda Integr Med. 2020 Oct-Dec;11(4):405-413. doi: 10.1016/j.jaim.2019.06.003. Epub 2020 Nov 2.
Polysaccharides decrease the glucose level by inhibiting α-glucosidase enzyme which further increases the level of GLP-1 (Glucagon-like peptide 1) to increase the insulin level as per earlier reports.
Similar hypothesis was designed in present study to investigate the α-glucosidase enzyme inhibition and involvement of GLP-1 in antidiabetic mechanism of Acacia tortilis polysaccharides (AEATP) in diabetic rats. Isolated polysaccharides were analyzed for their chemical nature by using HPLC and FTIR method.
Male albino wistar rats were divided into control, diabetic, diabetic + voglibose, diabetic + glimepiride, diabetic+250, 500, 1000 mg/kg of AEATP, diabetic + glimepiride + voglibose, diabetic + glimepiride+ 250, 500 and 1000 mg/kg AEATP, diabetic + GLP-1 antagonist+250, 500 and 1000 mg/kg AEATP. Plasma glucose, insulin and active GLP-1 levels were measured 15 min after OGTT. Fasting blood glucose, Plasma triglycerides, glycated hemoglobin (HbA1c), Fasting insulin, pancreatic insulin content, ileum and colon GLP-1 content were assessed at 5th week. Association of alpha-glucosidase was also assessed with GLP-1 and insulin.
AEATP significantly attenuated hyperglycemia by increasing insulin level in plasma and pancreas and increased active GLP-1 as well as insulin level in diabetic rats after OGTT. GLP-1 content was significantly increased in ileum and colon by inhibiting alpha-glucosidase. Involvement of GLP-1 in antihyperglycemic effect of AEATP was confirmed by using GLP-1 antagonist. Moreover, AEATP significantly improved dyslipidemia in diabetic rats. HPLC analysis of A. tortilis polysaccharide comprised four specific monosaccharides (Rhamnose, Glucuronic acid, glucose and galactose) and FTIR spectrum shown band at 3430.6 cm-1 (O-H stretching), 2940.3 cm (C-H linkage), 1630.4 cm (carbonyl stretching), 1410 cm (uronic acid) and 1030.5 cm (glycosidic linkage).
It can be concluded that antidiabetic effect of AEATP is through the modulation of GLP-1 level in plasma and intestinal tissue via alpha glucosidase inhibition.
根据早期报道,多糖通过抑制α-葡萄糖苷酶来降低血糖水平,进而提高胰高血糖素样肽-1(GLP-1)水平,以增加胰岛素水平。
本研究设计了类似的假说,以探讨金合欢多糖(AEATP)对糖尿病大鼠的抗糖尿病机制中α-葡萄糖苷酶抑制作用及GLP-1的参与情况。采用高效液相色谱法(HPLC)和傅里叶变换红外光谱法(FTIR)分析分离得到的多糖的化学性质。
将雄性白化Wistar大鼠分为对照组、糖尿病组、糖尿病+伏格列波糖组、糖尿病+格列美脲组、糖尿病+250、500、1000mg/kg AEATP组、糖尿病+格列美脲+伏格列波糖组、糖尿病+格列美脲+250、500和1000mg/kg AEATP组、糖尿病+GLP-1拮抗剂+250、500和1000mg/kg AEATP组。口服葡萄糖耐量试验(OGTT)15分钟后测定血浆葡萄糖、胰岛素和活性GLP-1水平。在第5周时评估空腹血糖、血浆甘油三酯、糖化血红蛋白(HbA1c)、空腹胰岛素、胰腺胰岛素含量、回肠和结肠GLP-1含量。还评估了α-葡萄糖苷酶与GLP-1和胰岛素的相关性。
AEATP通过提高血浆和胰腺中的胰岛素水平显著减轻高血糖,并在OGTT后提高糖尿病大鼠的活性GLP-1以及胰岛素水平。通过抑制α-葡萄糖苷酶,回肠和结肠中的GLP-1含量显著增加。使用GLP-1拮抗剂证实了GLP-1参与AEATP的降血糖作用。此外,AEATP显著改善了糖尿病大鼠的血脂异常。金合欢多糖的HPLC分析包含四种特定的单糖(鼠李糖、葡萄糖醛酸、葡萄糖和半乳糖),FTIR光谱在3430.6cm-1(O-H伸缩振动)、2940.3cm(C-H键)、1630.4cm(羰基伸缩振动)、1410cm(糖醛酸)和1030.5cm(糖苷键)处显示出谱带。
可以得出结论,AEATP的抗糖尿病作用是通过抑制α-葡萄糖苷酶来调节血浆和肠道组织中的GLP-1水平实现的。