Huang-lian-jie-du-decoction modulates glucagon-like peptide-1 secretion in diabetic rats.
OBJECTIVE
Huang-lian-jie-du-decoction (HLJDD), a well-known Chinese herbal formula, has been used for diabetic treatment. The purpose of the study was to investigate whether HLJDD affected glucagon-like peptide (GLP)-1 (7-36) amide level in diabetic rats.


METHODS
Streptozotocin (STZ)-induced diabetic rats were treated with HLJDD at low dose (2 g/kg/day) or high dose (4 g/kg/day). After 5-week treatment, GLP-1 (7-36) amide level and insulin level in portal vein and tissues stimulated by oral glucose load were measured by ELISA kits. The proglucagon gene expression in intestinal tracts and the proliferation of intestinal L cell and pancreatic beta cell were measured using RT-PCR and immunohistochemistry techniques, respectively.


RESULTS
It was found that 5-week HLJDD treatment attenuated alteration of glucose level and insulin level in plasma and tissues of diabetic rats induced by STZ, accompanied by improvement of diabetic syndrome. 5-week HLJDD treatment increased GLP-1 (7-36) amide level in portal vein plasma and distal ileum. Further studies showed that 5-week HLJDD treatment increased the mRNA level of proglucagon gene in distal ileum, promoted pancreatic beta cell and intestinal L cell proliferation in a dose-dependent manner.


CONCLUSIONS
All the results indicated that HLJDD exerted its anti-diabetic effects partly via modulating GLP-1 (7-36) amide level.
Yu
Yun-Li
YL
Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China.
Lu
Shou-Si
SS
Yu
Sen
S
Liu
Yu-Chun
YC
Wang
Ping
P
Xie
Lin
L
Wang
Guang-Ji
GJ
Liu
Xiao-Dong
XD
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000378:metabolism*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D004435:Eating / Q000187:drug effects; D052216:Glucagon-Like Peptide 1 / Q000378:metabolism*; D007150:Immunohistochemistry; D007202:Indicators and Reagents; D007328:Insulin / Q000097:blood; D050417:Insulin-Secreting Cells / Q000187:drug effects; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology; D052336:Proglucagon / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000894:Anti-Inflammatory Agents, Non-Steroidal; D001786:Blood Glucose; D004365:Drugs, Chinese Herbal; D007202:Indicators and Reagents; D007328:Insulin; D010936:Plant Extracts; D012333:RNA, Messenger; C061676:oren gedoku to; D052336:Proglucagon; D052216:Glucagon-Like Peptide 1