title: The anti-apoptotic effect of polypeptide from Chlamys farreri (PCF) in UVB-exposed HaCaT cells involves inhibition of iNOS and TGF-β1.
abstract: To investigate the molecular mechanisms of polypeptide from Chlamys farreri (PCF)'s anti-apoptotic effect, HaCaT cells were exposed to 20 mJ/CM(2) UVB, with or without pretreatment of TGF-β1 antagonist SB431542, inducible nitric oxide synthase (iNOS) inhibitor S-methylisothiourea sulfate (SMT), nitric oxide scavenger carboxy-PTIO, or 1.42, 2.84, and 5.69 mM PCF, or iNOS transfection (without UVB exposure). Apoptosis was confirmed with Hoechst 33258 staining; RT-PCR and western blot were used to determine the expression levels of iNOS and TGF-β1 signaling pathway. Both UVB exposure and iNOS transfection-induced apoptosis in UVB-exposed HaCat cells, while PCF, SB431542, SMT, and carboxy-PTIO all inhibited UVB-induced apoptosis. TGF-β1, Smad4, and Smad7 mRNA levels were all altered, similarly, iNOS, TGF-β1, and pSmad2/3 protein levels were all altered in UVB-exposed HaCaT cells. In pretreated cells, SB431542, SMT, carboxy-PTIO, and 1.42-5.69 mM PCF all inhibited UVB-induced apoptosis. Moreover, PCF treatment inhibited the expression levels of iNOS, TGF-β1, pSmad2/3, and Smad4, while increased the expression level of Smad7. SB431542 did not significantly alter iNOS expression, while SMT and carboxy-PTIO significantly altered TGF-β1 signaling level. The anti-apoptotic effect of PCF in UVB-exposed HaCaT cells involves the inhibition of iNOS expression and subsequently inhibition of TGF-β1 signaling pathway.
authors.affiliation: Department of Pharmacology, Qingdao University Medical College, Boya Building Room 422, 308 Ningxia Road, Qingdao, 266071, Shandong, China.
authors.forename: Yantao
authors.initials: Y
authors.lastname: Han
authors.forename: Qixiao
authors.initials: Q
authors.lastname: Jiang
authors.forename: Hui
authors.initials: H
authors.lastname: Gao
authors.forename: Jie
authors.initials: J
authors.lastname: Fan
authors.forename: Zhi
authors.initials: Z
authors.lastname: Wang
authors.forename: Feng
authors.initials: F
authors.lastname: Zhong
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zheng
authors.forename: Zhuoqun
authors.initials: Z
authors.lastname: Gong
authors.forename: Chunbo
authors.initials: C
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects* / Q000528:radiation effects*; D001549:Benzamides / Q000494:pharmacology; D002460:Cell Line; D004149:Dioxoles / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D007550:Isothiuronium / Q000031:analogs & derivatives / Q000494:pharmacology; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000235:genetics; D049897:Pectinidae; D010455:Peptides / Q000494:pharmacology*; D010750:Phosphoproteins / Q000378:metabolism; D051785:Smad Proteins / Q000235:genetics / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000037:antagonists & inhibitors* / Q000235:genetics; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: C459179:4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamide; D001549:Benzamides; D004149:Dioxoles; D010455:Peptides; D010750:Phosphoproteins; D051785:Smad Proteins; D053773:Transforming Growth Factor beta1; D007550:Isothiuronium; D052247:Nitric Oxide Synthase Type II; C027744:S-methylisothiopseudouronium