title: Molecular mechanisms of gallic acid-induced growth inhibition, apoptosis, and necrosis in hypertrophic scar fibroblasts.
abstract: OBJECTIVE
  To explore the effect and molecular mechanism of gallic acid (GA) on the cytostatic and cytotoxicity of hypertrophic scar fibroblasts (HSFs).
  
  
  METHODS
  HSFs were treated with a serial dose of GA for indicated time. The cytostatic and cytotoxicity of GA were evaluated by microscopy, trypan blue exclusion assay and LDH releasing. The mechanisms of GA-induced cytostatic were examined by cell cycle distribution assay and the expression of cell cycle-relative protein. GA-elicited apoptosis were verified by TUNEL assay, mitochondria membrane potential, caspase activity and the expression of apoptosis-relative protein. GA-induced necrosis was confirmed by lysosome rupture using acridine orange stain. Various blockers, including intracellular calcium chelator; BAPTA-AM, IP3R blocker; 2-APB, calpain inhibitor, ALLM and ALLN were used to address the signaling cascade in GA-induced HSF necrosis.
  
  
  RESULTS
  GA-induced growth inhibition, apoptosis, and necrosis in HSFs depend on increasing dose. HSFs treated with GA at non-cytotoxic concentrations (50 to 75μM) significant increased both the S- and G2/M-phase HSFs population, and this event was accompanied with down-regulation of cyclin A, cyclin B, CDK1 and CDK2. Incubation of HSFs with 100-150μM of GA induced apoptosis through Bcl2/Bax-mitochondrial-dependent pathway. While the concentrations up to 200μM of GA that elicited necrosis via a calcium/calpain I/lysosome rupture signaling axis. Interestingly, GA at 200μM did not harm to keratinocyte.
  
  
  CONCLUSIONS
  These results revealed that GA might have the potential to be developed as a treatment for patients with hypertrophic scar.
authors: Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan; Department of Education & Research, Taichung Veterans General Hospital, Taichung, Taiwan.
authors: Shu-Chung
authors: SC
authors: Hsieh
authors: Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors: Chun-Chi
authors: CC
authors: Wu
authors: Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan; Department of Education & Research, Taichung Veterans General Hospital, Taichung, Taiwan.
authors: Shih-Lan
authors: SL
authors: Hsu
authors: Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan; Division of Plastic Surgery, Department of Surgery, Taichung Veterans General Hospital, Taiwan. Electronic address: rsyen@vghtc.gov.tw.
authors: Jung-Hsing
authors: JH
authors: Yen
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D002154:Calpain / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D002478:Cells, Cultured; D017439:Cicatrix, Hypertrophic / Q000188:drug therapy* / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects* / Q000473:pathology; D005707:Gallic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D020287:In Situ Nick-End Labeling; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D008247:Lysosomes / Q000187:drug effects / Q000378:metabolism; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D009336:Necrosis / Q000188:drug therapy; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D005707:Gallic Acid; D002154:Calpain; D002118:Calcium
keywords: Apoptosis; Gallic acid; Growth inhibition; Hypertrophic scar fibroblast; Necrosis