The effect of curcumin on insulin release in rat-isolated pancreatic islets.
Curcumin exerts a hypoglycemic action and induces heme-oxygenase-1 (HO-1). We evaluated the effect of curcumin on isolated islets of Langerhans and studied whether its action on insulin secretion is mediated by inducible HO-1. Islets were isolated from rats and divided into control islets, islets incubated in different curcumin concentrations, islets incubated in hemin, islets incubated in curcumin and HO inhibitor, stannous mesoporphyrin (SnMP), islets incubated in hemin and SnMP, islets incubated in SnMP only, and islets incubated in 16.7 mmol/L glucose. Heme-oxygenase activity, HO-1 expression, and insulin estimation was assessed. Insulin secretion, HO-1 gene expression and HO activity were significantly increased in islets incubated in curcumin, hemin, and glucose compared with controls. This increase in insulin secretion was significantly decreased by incubation of islets in SnMP. The action of curcumin on insulin secretion from the isolated islets may be, in part, mediated through increased HO-1 gene expression.
Abdel Aziz
Mohamed T
MT
Department of Medical Biochemistry, Cairo University, Egypt. talaatabdaziz@yahoo.co.uk
El-Asmar
Mohamed F
MF
El Nadi
Essam G
EG
Wassef
Mohamed A
MA
Ahmed
Hanan H
HH
Rashed
Laila A
LA
Obaia
Eman M
EM
Sabry
Dina
D
Hassouna
Amira A
AA
Abdel Aziz
Ahmed T
AT
D000818:Animals; D003474:Curcumin / Q000494:pharmacology*; D017931:DNA Primers; D004587:Electrophoresis, Agar Gel; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D005947:Glucose / Q000494:pharmacology; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism*; D006427:Hemin / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D007515:Islets of Langerhans / Q000187:drug effects* / Q000378:metabolism; D008665:Metalloporphyrins / Q000494:pharmacology; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D007328:Insulin; D008665:Metalloporphyrins; C518404:stannous mesoporphyrin; D006427:Hemin; D051547:Heme Oxygenase-1; D003474:Curcumin; D005947:Glucose