Fructus Corni suppresses hepatic gluconeogenesis related gene transcription, enhances glucose responsiveness of pancreatic beta-cells, and prevents toxin induced beta-cell death.
BACKGROUND
Fructus Corni, the fruits of Cornus officinalis Sieb. et Zucc., is one important ingredient in Quei Fu Di Huang Wan, a Chinese herbal mixture.


OBJECTIVE
In the present study, additional anti-diabetic actions of Fructus Corni on transcriptional regulation of hepatic gluconeogenesis or beta-cell functions were investigated.


METHODS
Insulin mimetic action of Fructus Corni on dexamethasone and 8-bromo-cAMP induced phosphoenolpyruvate carboxykinase (PEPCK) expression in H4IIE cells was investigated. Besides, BRIN-BD11 cells were used to evaluate both insulinotropic and beta-cell protective effect of Fructus Corni.


RESULTS
Firstly, both methanol extract (CO-W-M) and fraction (CO-W-M2) had potent insulin mimic activity on PEPCK expression. Secondly, possibility of both loganin and ursolic acid as the responsible compounds was excluded. Moreover, indication of the existence of phenolic compounds in CO-W-M2 was noticed. In the presence of CO-W-M2, not only was the viability of BRIN-BD11 cells treated with alloxan, streptozotcin, or cytokine mix all significantly increased but also glucose-stimulated insulin secretion was potentiated.


CONCLUSIONS
The ability of CO-W-M2 to reduce gene expression for hepatic gluconeogenesis, to protect beta-cell against toxic challenge, and to enhance insulin secretion strengthen the role of Fructus Corni in diabetes therapy.
Chen
Chien-Chih
CC
Division of Medicinal Chemistry, National Research Institute of Chinese Medicine, Taipei, Taiwan, ROC.
Hsu
Chia-Yun
CY
Chen
Chin-Ying
CY
Liu
Hui-Kang
HK
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D015153:Blotting, Western; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D029768:Cornus / Q000737:chemistry*; D003907:Dexamethasone / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism / Q000517:prevention & control; D004591:Electrophoresis, Polyacrylamide Gel; D005638:Fruit / Q000737:chemistry; D015870:Gene Expression / Q000187:drug effects; D005943:Gluconeogenesis / Q000187:drug effects*; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000096:biosynthesis; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism*; D039823:Iridoids / Q000737:chemistry / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D019764:Phosphoenolpyruvate Carboxykinase (ATP) / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D014315:Triterpenes / Q000737:chemistry / Q000494:pharmacology; D000097245:Ursolic Acid
D015124:8-Bromo Cyclic Adenosine Monophosphate; D003907:Dexamethasone; D005947:Glucose; D007328:Insulin; D039823:Iridoids; D019764:Phosphoenolpyruvate Carboxykinase (ATP); D012333:RNA, Messenger; D014315:Triterpenes; D000097245:Ursolic Acid; C059516:loganin