Ammonia — new therapeutic target for chronic liver diseases

Objective: to study some mechanisms of progression of chronic liver diseases in patients with initial stage of liver fi brosis and the possibility of their correction.

Materials and methods: a total of 69 young patients with chronic liver diseases with initial stage 0–2 fi brosis (26 patients with chronic viral hepatitis C, 43 patients with nonalcoholic steatohepatitis) were examined. Ammonia levels were determined in peripheral blood by the method of single photometry reveals on the analyzer PocketChem BA, ArcRay (Japan), for the integral evaluation of intrahepatic blood fl ow disorders was used polyhepatography (PHG) is a non — invasive method.The intensity of the activity of the stellate cells of the liver (HSCs) was determined according to the expression of SMA-alpha in a liver biopsy sample. In terms of correction of hyperammoniemia and portohepatic hemodynamics disorders in our study used hepatoprotector with hypoammoniemic eff ect ornithine (L-ornithine-L-aspartate).

Results: ammonia levels in HCV patients and NASH patients was signifi cantly higher than in the control group, the level of hyperammoniemia prevailed in patients with NASH than HCV patients. Portohepatic hemodynamics disorders were detected in all patients, while the peculiarities of these disorders, depending on the etiology of hepatitis. These hemodynamic disorders were accompanied by signs of activation of HSCs. In the liver tissue we revealed expression of SMA-alpha in HSCs, indicating that the signs of activation of these cells. Efficiencyanalysis of the eff ectiveness of Ornithine showed a signifi cant reduction of ammonia in the blood and improvement in intrahepatic blood fl ow in patients with diff erent types of portohepatic hemodynamics disorders on the background of treatment.

Conclusion: in HCV and NASH patients, already at the initial stage sofl iver fi brosis, hyperammoniemia was detected (with HCV it was signifi cantly higher), activation of HSCs, which leads to impaired portohepatic hemodynamics in these patients. The use of a hepatoprotector with the hypoammoniemic eff ect Ornithine leads to a decrease of blood ammonia and an improvement of hepatic microcirculation, which allows expanding the possibilities of the pathogenetic treatment of chronic hepatitis for decrease of fi brogenesis.

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