The aim of this study was to study the effect of combined MMSC and HSC transplantation on liver regeneration under conditions of toxic carbon tetrachloride damage. Materials and methods. The study was performed on white male mice with toxic liver damage by intraperitoneal administration of carbon tetrachloride at a dose of 50 µl per mouse once. An hour after modeling liver damage, placental MMSCs and HSCs were administered intravenously at a dose of 4 million cells/kg and 330 thousand cells/kg, respectively, suspended in 0.2 ml of 0.9% NaCl solution. Control group animals were given 0.9% NaCl solution-0.2 ml intravenously. On days 1, 3, and 7 after cell transplantation, changes in inflammatory activity in the liver were evaluated, and mitotic and apoptotic indices were determined. On the 7th day after the introduction of cells, the activity of DNA repair enzymes of the PARP family was analyzed. Results. Combined MMSC and HSC transplantation leads to a decrease in the index of inflammatory activity in the liver due to a decrease in necrosis, hepatocyte dystrophy, and a decrease in infiltration. As a result of the study, an increase in the activity of PARP repair enzymes was found, which led to a decrease in programmed cell death. Also, cotransplantation of MMSCs and HSCs was accompanied by increased mitotic activity of hepatocytes. Conclusion. Cotransplantation of MMSCs and HSCs under conditions of toxic liver damage reduces the inflammatory response, stimulates the mitotic activity of hepatocytes, and increases the activity of enzymes of the DNA repair system. Activation of the liver's reparative system, in turn, reduces the programmed death of hepatocytes.
