KR-31378, a novel benzopyran analog, attenuates hypoxia-induced cell death via mitochondrial KATP channel and protein kinase C-epsilon in heart-derived H9c2 cells.
A novel compound KR-31378 [(2S,3S,4R)-N''-cyano-N-(6-amino-3,4-dihydro-3-hydroxy-2-methly-2-dimethoxy-methly-2H-benzo-pyran-4-yl)-N-benzylguanidine] has been demonstrated as an anti-ischemic agent in rat heart and brain. Here, we report the effects of this compound on hypoxia-induced cell death and possible signaling pathways in heart-derived H9c2 cells. Treatment with KR-31378 (3-30 microM) 1 h before and during hypoxia significantly reduced hypoxia-induced cell death in a concentration-dependent manner. In addition, increase in hypoxia-induced transferase UTP nick end labeling (TUNEL)-positive cells was reduced by KR-31378, suggesting its antiapoptotic potential in H9c2 cells. The protective effect conferred by KR-31378 (10 microM) was abolished by cotreatment with 5-hydroxydecanoate (5HD), a specific blocker of the mitochondrial KATP (mtKATP) channel, but not by HMR-1883 (1-[[5-[2-(5-chloro-o-anisamido)ethyl]-methoxyphenyl]sulfonyl]-3-methylthiourea), a specific blocker of the sarcolemmal KATP channel. We observed that the treatment with KR-31378 could increase the expression of protein kinase C (PKC)-epsilon protein, but not other PKC isotypes (-alpha, -beta, -delta, -zeta), in the particulate fraction. This increased level of PKC-epsilon was sustained during the hypoxic period up to 8 h. In addition, our results showed that treatment with KR-31378 induced the expression of PKC-epsilon mRNA as early as 15 min after the treatment. A specific inhibitor for PKC-epsilon isoform, epsilonV1-2, completely blocked the protective effect of KR-31378 against hypoxia-induced cell death. In conclusion, our results suggest that KR-31378 can protect cultured H9c2 cells from hypoxia-induced death via the mtKATP channel and PKC-epsilon.
Moon
Chang-Hyun
CH
Department of Physiology, School of Medicine Ajou University, #5 Woncheon-dong, Suwon 442-749, South Korea.
Kim
Mi-Young
MY
Kim
Mi Jeong
MJ
Kim
Min Hwa
MH
Lee
Sunkyung
S
Yi
Kyu Yang
KY
Yoo
Sung Eun
SE
Lee
Dong-Ha
DH
Lim
Hong
H
Kim
Ho Soon
HS
Lee
Soo Hwan
SH
Baik
Eun Joo
EJ
Jung
Yi-Sook
YS
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D015687:Cell Hypoxia; D002460:Cell Line; D003652:Decanoic Acids / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006146:Guanidines / Q000494:pharmacology*; D006880:Hydroxy Acids / Q000494:pharmacology; D020287:In Situ Nick-End Labeling; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008929:Mitochondria, Heart / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015221:Potassium Channels / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism*; D051744:Protein Kinase C-epsilon; D011714:Pyrans / Q000494:pharmacology*; D013449:Sulfonamides / Q000494:pharmacology; D013890:Thiourea / Q000031:analogs & derivatives* / Q000494:pharmacology; D013997:Time Factors
D003652:Decanoic Acids; D006146:Guanidines; D006880:Hydroxy Acids; D008565:Membrane Proteins; C438686:N''-cyano-N-(6-amino-3,4-dihydro-3-hydroxy-2-methyl-2-dimethoxymethyl-2H-benzopyran-4-yl)-N'-benzylguanidine; D015221:Potassium Channels; D011714:Pyrans; D013449:Sulfonamides; C117780:mitochondrial K(ATP) channel; C052853:5-hydroxydecanoic acid; C114623:clamikalant; D011493:Protein Kinase C; D051744:Protein Kinase C-epsilon; D013890:Thiourea