Role of Stem Cells Transplantation in Tissue Regeneration After Acute or Chronic Acetaminophen Induced Liver Injury

Morphology of Acute Liver Failure During Treatment With a Combination of Drug Therapy and Transplanted Cultured Hepatocytes

OBJECTIVES

We analyzed liver tissue morphology dynamics in experimental animals with acute liver failure during treatment with a combination of transplanted cultured embryonic hepatocytes and the hepatoprotective drug Erbisol.

MATERIALS AND METHODS

We studied 30 white outbred male rats weighing 250 to 350 g, divided into 6 groups with 5 animals in each group. Acute liver damage was induced by a hepatotoxic model of acute liver failure for which carbon tetrachloride was applied (200 μg CCl4/100 g body weight with toxin-to-oil volume ratio of 1:1). To obtain cultured embryonic hepatocytes, we used an enzymatic-mechanical process that caused only minimal cell damage. This method is known to improve the output of viable cultured embryonic hepatocytes, improve the morphological-functional properties of the hepatocytes, and reduce the process time during procurement, and thereby reduce the overall time from procurement to the subsequent culturing of the obtained cells. Transplant of cultured embryonic hepatocytes was performed intrape-ritoneally at a dose of 50 million (0.5 × 108) cells. Morphological studies were performed on day 7 and day 21 of the experiment.

RESULTS AND CONCLUSIONS

There were significant morphological changes in livers from animals with acute liver failure, caused by widespread necrosis and an elevated inflammatory response. Treatment with injections of cultured embryonic hepatocytes induced regeneration of the liver parenchyma cells and reduced the inflammatory response, both of which were further reduced in rats that received combined treatment of transplant with Erbisol. Combined application of cultured embryonic hepatocytes and Erbisol potentiated the effects of both treatments, which produced intensive proliferation of hepatocytes, hypertrophy and polyploidization of hepatocyte nuclei, and an early restoration of liver structure and organ mass.

Application of Modified Mesenchymal Stem Cells Transplantation in the Treatment of Liver Injury

Acute and chronic hepatitis, cirrhosis, and other liver diseases pose a serious threat to human health; however, liver transplantation is the only reliable treatment for the terminal stage of liver diseases. Previous researchers have shown that mesenchymal stem cells (MSCs) are characterized by differentiation and paracrine effects, as well as anti-oxidative stress and immune regulation functions. When MSCs are transplanted into animals, they migrate to the injured liver tissue along with the circulation, to protect the liver and alleviate the injury through the paracrine, immune regulation and other characteristics, making mesenchymal stem cell transplantation a promising alternative therapy for liver diseases. Although the efficacy of MSCs transplantation has been confirmed in various animal models of liver injury, many researchers have also proposed various pretreatment methods to improve the efficacy of mesenchymal stem cell transplantation, but there is still lack a set of scientific methods system aimed at improving the efficacy of transplantation therapy in scientific research and clinical practice. In this review, we summarize the possible mechanisms of MSCs therapy and compare the existing methods of MSCs modification corresponding to the treatment mechanism, hoping to provide as a reference to help future researchers explore a safe and simple transplantation strategy.

Wnt/β-Catenin Signaling Drives Thioacetamide-Mediated Heteroprotection Against Acetaminophen-Induced Lethal Liver Injury

Preplacement of compensatory tissue repair (CTR) by exposure to a nonlethal dose of a toxicant protects animals against a lethal dose of another toxicant. Although CTR is known to heteroprotect, the underlying molecular mechanisms are not completely known. Here, we investigated the mechanisms of heteroprotection using thioacetamide (TA): acetaminophen (APAP) heteroprotection model. Male Swiss Webster mice received a low dose of TA or distilled water (DW) vehicle 24 hours prior to a lethal dose of APAP. Liver injury, tissue repair, and promitogenic signaling were studied over a time course of 24 hours after APAP overdose to the TA- and DW-primed mice (TA + APAP and DW + APAP, respectively). Thioacetamide pretreatment afforded 100% protection against APAP overdose compared to 100% lethality in the DW + APAP-treated mice. Although hepatic Cyp2e1 was similar at the time of APAP administration, immediate activation of hepatic c-Jun N-terminal kinases (JNK) was observed in the TA + APAP-treated mice compared to its delayed activation in the DW + APAP group. In contrast to the DW + APAP group, the TA + APAP-treated mice exhibited extensive CTR, which was secondary to the timely activation of Wnt/β-catenin pathway. Our data indicate that rapid activation and appropriate termination of Wnt/β-catenin signaling and modulation of JNK activity underlie TA + APAP heteroprotection.

Digestive system damage in acute poisoning and treatment strategy

Acute intoxication is a common critical clinical condition. Poisoning patients tend to have an urgent onset, critical illness and rapid progression. If timely and reasonable treatment is not given, there will be a serious threat to patients' life. Drugs, alcohol, pesticides, and poisonous chemicals are clinically common toxic substances, and oral suicide is a major cause of poisoning. Therefore, suicidal patients absorb poison mainly through the digestive tract, and digestive system damage is common and serious. Awareness of digestive system damage in patients with acute poisoning and treatment measures has important clinical significance for improving the overall prognosis of these patients. This paper discusses the latest research progress in understanding digestive system damage in acute poisoning and treatment strategy.

Revaluation of vanishing bile duct syndrome

Vanishing bile duct syndrome (VBDS) can result from multiple etiologies, including congenital and genetic diseases, ischemic causes, neoplastic disorders, infections, immune disorders, drugs, idiopathic adulthood ductopenia (IAD) and so on. Recently, lymphoma, HIV/AIDS and drugs were identified to be major etiologies in the reported cases, some of which presented complex clinical course and were contributed by more than one etiological factor. Hepatic biopsy must be done for the diagnosis of VBDS and immunohistochemical staining for cytokeratin 7 (CK7) and CK19 has contributed to the establishment of diagnosis of VBDS. VBDS can be usually treated with symptomatic and supportive therapy, etiological therapy, liver transplantation, ursodeoxycholic acid and immunosuppressive agents. Glucocorticoids can be tried to switch to mycophemolate mofeil or tacrolimus when their effects are poor or side effects are severe. Severe cases ought to receive multimodality therapy besides plasmapheresis.