Insulinotropic effect of cinnamaldehyde on transcriptional regulation of pyruvate kinase, phosphoenolpyruvate carboxykinase, and GLUT4 translocation in experimental diabetic rats.
Diabetes mellitus is a chronic metabolic disorder affecting about 6% of population worldwide with its complications and is rapidly reaching epidemic scale. Cinnamomum zeylanicum is widely used in alternative system of medicine for treatment of diabetes. In the present study, we have performed bioassay guided fractionation of chloroform extract of C. zeylaniucm and identified cinnamaldehyde (CND) as an active principle against diabetes. In continuation to it, a detailed study was undertaken to elucidate its mode of antidiabetic action in STZ induced diabetic rats. Oral administration of CND (20 mg/kg bw) to diabetic rats for 2 months showed significant improvement (p<0.001) in muscle and hepatic glycogen content. In vitro incubation of pancreatic islets with CND enhanced the insulin release compared to glibenclamide. The insulinotropic effect of CND was found to increase the glucose uptake through glucose transporter (GLUT4) translocation in peripheral tissues. The treatment also showed a significant improvement in altered enzyme activities of pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK) and their mRNA expression levels. Furthermore, the median lethal dose (LD(50)) of CND could not be obtained even at 20 times (0.4 g/kg bw) of its effective dose. With the high margin of safety of CND, it can be developed as a potential therapeutic candidate for the treatment of diabetes.
Anand
Prachi
P
Dr. B.R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India. panand@acbr.du.ac.in
Murali
K Y
KY
Tandon
Vibha
V
Murthy
P S
PS
Chandra
Ramesh
R
D000171:Acrolein / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002935:Cinnamomum zeylanicum / Q000737:chemistry; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy*; D004326:Drinking / Q000187:drug effects; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D006003:Glycogen / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D007328:Insulin / Q000097:blood*; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000378:metabolism; D007668:Kidney / Q000187:drug effects / Q000201:enzymology; D007928:Lethal Dose 50; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D019764:Phosphoenolpyruvate Carboxykinase (ATP) / Q000378:metabolism; D010729:Phosphoenolpyruvate Carboxykinase (GTP) / Q000378:metabolism; D011770:Pyruvate Kinase / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D051275:Glucose Transporter Type 4; D007004:Hypoglycemic Agents; D007328:Insulin; D000171:Acrolein; D006003:Glycogen; D011770:Pyruvate Kinase; D010729:Phosphoenolpyruvate Carboxykinase (GTP); D019764:Phosphoenolpyruvate Carboxykinase (ATP); C012843:cinnamaldehyde