Inhibition of histone deacetylase 6 restores intestinal tight junction in hemorrhagic shock Journal Article

Authors: Chang, Z.; Li, Y; He, W.; Liu, B.; Duan, X.; Halaweish, I.; Bambakidis, T.; Pan, B.; Liang, Y; Nikolian, V. C.; Georgoff, P.; Alam, H. B.
Article Title: Inhibition of histone deacetylase 6 restores intestinal tight junction in hemorrhagic shock
Abstract: BACKGROUND: We recently discovered that Tubastatin-A, histone deacetylase (HDAC6) inhibitor, can improve survival in a rodent model of hemorrhagic shock (HS), but mechanisms remain poorly defined. In this study we investigated whether Tubastatin-A could protect intestinal tight junction (TJ) in HS. METHODS: In-vivo study: Wistar-Kyoto rats underwent HS (40% blood loss) followed by Tubastatin-A (70 mg/kg) treatment, without fluid resuscitation. The experimental groups were: (1) sham (no hemorrhage, no treatment), (2) control (hemorrhage, without treatment), and (3) treatment (hemorrhage with Tubastatin-A administration). Three hours after hemorrhage, ileum was harvested. Whole cell lysate were analyzed for acetylated alpha-tubulin (Ac-tubulin), total tubulin, acetylated histone 3 at lysine 9 (Ac-H3K9), beta-actin, claudin-3 and zonula occludens 1 (ZO-1) proteins by western blot. Histological effects of Tubastatin-A on small bowel were examined. In-vitro study: human intestinal epithelial cells (Caco-2) were divided into 3 groups: (1) sham (normoxia), (2) control (anoxia, no treatment), (3) treatment (anoxia, treatment with Tubastatin-A). After 12 hours in a anoxia chamber, the cells were examined for Ac-tubulin and Ac-H3K9, cellular viability, cytotoxicity, claudin-3 and ZO-1 protein expression, and transwell permeability study. RESULTS: Tubastatin-A treatment significantly attenuated HS-induced decreases of Ac-tubulin, Ac-H3K9, ZO-1 and claudin-3 proteins in small bowel in-vivo (P0.05). In cultured Caco-2 cells, anoxia significantly decreased cellular viability (P0.001) and increased cytotoxicity (P0.001) compared to the sham group, while Tubastatin-A treatment offered significant protection (P0.0001). Moreover, expression of claudin-3 was markedly decreased in-vitro compared to the sham group, whereas this was significantly attenuated by Tubastatin-A (P0.05). Finally, anoxia markedly increased the permeability of Caco-2 monolayer cells (P0.05), while Tubastatin-A significantly attenuated the alteration (P0.05). CONCLUSION: Inhibition of HDAC6 can induce Ac-tubulin and Ac-H3K9, promote cellular viability, and prevent the loss of intestinal TJ proteins during HS and anoxia.
Journal Title: The journal of trauma and acute care surgery
ISSN: 2163-0763; 2163-0755
Publisher: Unknown  
Date Published: 2016
Language: ENG
Notes: LR: 20160701; GR: R01 GM084127/GM/NIGMS NIH HHS/United States; JID: 101570622; aheadofprint