PURPOSE: Oxidative stress and inflammation contribute to hepatic injury after hemorrhage/resuscitation (H/R). Natural plant polyphenols, i.e., green tea extract (GTE) possess high anti-oxidant and anti-inflammatory activities in various models of acute inflammation. However, possible protective effects and feasible mechanisms by which plant polyphenols modulate pro-inflammatory, apoptotic, and oxidant signaling after H/R in the liver remain unknown. Therefore, we investigated the effects of GTE and its impact on the activation of NF-kappaB in the pathogenesis of hepatic injury induced by H/R. METHODS: Twenty-four female LEWIS rats (180-250 g) were fed a standard chow (ctrl) or a diet containing 0.1% polyphenolic extracts (GTE) from Camellia sinensis starting 5 days before H/R. Rats were hemorrhaged to a mean arterial pressure of 30 ± 2 mmHg for 60 min and resuscitated (H/R and GTE H/R groups). Control groups (sham, ctrl, and GTE) underwent surgical procedures without H/R. Two hours after resuscitation, tissues were harvested. RESULTS: Plasma alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) increased 3.5-fold and fourfold, respectively, in vehicle-treated rats as compared to GTE-fed rats. Histopathological analysis revealed significantly decreased hepatic necrosis and apoptosis in GTE-fed rats after H/R. Real-time PCR showed that GTE diminished gene expression of pro-apoptotic caspase-8 and Bax, while anti-apoptotic Bcl-2 was increased after H/R. Hepatic oxidative (4-hydroxynonenal) and nitrosative (3-nitrotyrosine) stress as well as systemic IL-6 level and hepatic IL-6 mRNA were markedly reduced in GTE-fed rats compared with controls after H/R. Plant polyphenols also decreased the activation of both JNK and NFκB. CONCLUSIONS: Taken together, GTE application blunts hepatic damage, apoptotic, oxidative, and pro-inflammatory changes after H/R. These results underline the important roles of JNK and NF-kappaB in inflammatory processes after H/R and the beneficial impact of plant polyphenols in preventing their activation.
PURPOSE: Oxidative stress and inflammation contribute to hepatic injury after hemorrhage/resuscitation (H/R). Natural plant polyphenols, i.e., green tea extract (GTE) possess high anti-oxidant and anti-inflammatory activities in various models of acute inflammation. However, possible protective effects and feasible mechanisms by which plant polyphenols modulate pro-inflammatory, apoptotic, and oxidant signaling after H/R in the liver remain unknown. Therefore, we investigated the effects of GTE and its impact on the activation of NF-kappaB in the pathogenesis of hepatic injury induced by H/R. METHODS: Twenty-four female LEWIS rats (180-250 g) were fed a standard chow (ctrl) or a diet containing 0.1% polyphenolic extracts (GTE) from Camellia sinensis starting 5 days before H/R. Rats were hemorrhaged to a mean arterial pressure of 30 ± 2 mmHg for 60 min and resuscitated (H/R and GTE H/R groups). Control groups (sham, ctrl, and GTE) underwent surgical procedures without H/R. Two hours after resuscitation, tissues were harvested. RESULTS: Plasma alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) increased 3.5-fold and fourfold, respectively, in vehicle-treated rats as compared to GTE-fed rats. Histopathological analysis revealed significantly decreased hepatic necrosis and apoptosis in GTE-fed rats after H/R. Real-time PCR showed that GTE diminished gene expression of pro-apoptotic caspase-8 and Bax, while anti-apoptotic Bcl-2 was increased after H/R. Hepatic oxidative (4-hydroxynonenal) and nitrosative (3-nitrotyrosine) stress as well as systemic IL-6 level and hepatic IL-6 mRNA were markedly reduced in GTE-fed rats compared with controls after H/R. Plant polyphenols also decreased the activation of both JNK and NFκB. CONCLUSIONS: Taken together, GTE application blunts hepatic damage, apoptotic, oxidative, and pro-inflammatory changes after H/R. These results underline the important roles of JNK and NF-kappaB in inflammatory processes after H/R and the beneficial impact of plant polyphenols in preventing their activation.
Authors: Nils Wagner; Scott Dieteren; Niklas Franz; Kernt Köhler; Katharina Mörs; Luka Nicin; Julia Schmidt; Mario Perl; Ingo Marzi; Borna Relja Journal: PLoS One Date: 2018-02-08 Impact factor: 3.240
Authors: G Wetzel; B Relja; A Klarner; D Henrich; N Dehne; B Brühne; M Lehnert; I Marzi Journal: Mediators Inflamm Date: 2014-06-01 Impact factor: 4.711