Activating effect of momordin, extract of bitter melon (Momordica Charantia L.), on the promoter of human PPARdelta.
OBJECTIVE
Bitter melon (Momordica charantia L.) is a common vegetable grown in Okinawa that has also been used recently in medicine for the treatment of diseases such as diabetes, hypertension, and dyslipidemia. Among Bitter melon extracts compounds, we focused on an extract known as momordin in the present study, to examine its effect on peroxisome-proliferator activated-receptor (PPAR) delta (also called PPARdelta in rodents) expression and promoter activity of the human PPARdelta gene.


METHODS
A human PPARdelta promoter-reporter plasmid was made as a template from a BAC CLONE (RPCI-11C) containing a -3076 bp (BglI site) +74 bp (EcoRI site) sequence. Luciferase assay of PPARdelta promoter activity was performed using HepG2 cells.


RESULTS
10 and 25 nM Momordin significantly increased the expression of PPARdelta mRNA 1.5-fold (relative to the control). Moreover, 10 and 25 nM Momordin significantly increased PPARdelta promoter activity in a dose-dependent manner, reaching more than 1.5-fold relative to the control.


CONCLUSIONS
Our present data obtained through successful cloning of the PPARdelta promoter demonstrate that PPARdelta production and activation are upregulated through PPARdelta promoter activity following momordin treatment.
Sasa
Masatoshi
M
Department of Diabetes and Endocrinology, Saitama Medical University, Japan.
Inoue
Ikuo
I
Shinoda
Yuichi
Y
Takahashi
Seiichiro
S
Seo
Makoto
M
Komoda
Tsugikazu
T
Awata
Takuya
T
Katayama
Shigehiro
S
D002460:Cell Line; D003001:Cloning, Molecular; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D005786:Gene Expression Regulation; D056945:Hep G2 Cells; D006801:Humans; D029777:Momordica charantia / Q000378:metabolism*; D047494:PPAR delta / Q000235:genetics*; D008517:Phytotherapy / Q000379:methods; D010936:Plant Extracts / Q000494:pharmacology*; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D015854:Up-Regulation
D047494:PPAR delta; D010936:Plant Extracts; C548297:momordin