S-nitroso-N-acetylcysteine ameliorates ischemia-reperfusion injury in the steatotic liver

BACKGROUND: Steatosis is currently the most common chronic liver disease and it can aggravate ischemia-reperfusion (IR) lesions. We hypothesized that S-nitroso-N-acetylcysteine (SNAC), an NO donor component, can ameliorate cell damage from IR injury. In this paper, we report the effect of SNAC on liver IR in rats with normal livers compared to those with steatotic livers. METHODS: Thirty-four rats were divided into five groups: I (n=8), IR in normal liver; II (n=8), IR in normal liver with SNAC; III (n=9), IR in steatotic liver; IV (n=9), IR in steatotic liver with SNAC; and V (n=10), SHAN. Liver steatosis was achieved by administration of a protein-free diet. A SNAC solution was infused intraperitoneally for one hour, beginning 30 min. after partial (70 percent) liver ischemia. The volume of solution infused was 1 ml/100 g body weight. The animals were sacrificed four hours after reperfusion, and the liver and lung were removed for analysis. We assessed hepatic histology, mitochondrial respiration, oxidative stress (MDA), and pulmonary myeloperoxidase. RESULTS: All groups showed significant alterations compared with the group that received SHAN. The results from the steatotic SNAC group revealed a significant improvement in liver mitochondrial respiration and oxidative stress compared to the steatotic group without SNAC. No difference in myeloperoxidase was observed. Histological analysis revealed no difference between the non-steatotic groups. However, the SNAC groups showed less intraparenchymal hemorrhage than groups without SNAC (p=0.02). CONCLUSION: This study suggests that SNAC effectively protects against IR injury in the steatotic liver but not in the normal liver.

Efeito protetor da reduçäo do conteúdo enzimático do pâncreas na lesäo pulmonar da pancreatite aguda / Protective effect of reduction of pancreatic enzyme content on the pancreas in acute pulmonary pancreatitis

A lesao pulmonar surge em até 50-70 por cento dos pacientes com pancreatite aguda. A infusao de ceruleína em doses fisiológicas reduz o conteúdo enzimático do pâncreas com diminuiçao da taxa de mortalidade da pancreatite. Com objetivo de avaliar o efeito da reduçao do conteúdo enzimático do pâncreas sobre a lesao pulmonar da pancreatite aguda, foi induzida pancreatite em ratos Wistar através da infusao, dentro do ducto biliar, de soluçao de taurocolato de sódio a 5 por cento: grupo I, ratos com pancreatite; grupo II, ratos nos quais pancreatite foi induzida somente após reduçao do conteúdo enzimático do pâncreas, e grupo III, controle. A lesao pulmonar foi avaliada através da utilizaçao do corante azul de Evans, sendo menor no grupo II comparativamente ao I (P O,05). Especula-se que a reduçao do conteúdo enzimático do pâncreas diminui a lesao pulmonar da pancreatite aguda pela reduçao da quantidade de enzimas que atinge a circulaçao sistêmica.