Research Article Details
| Article ID: | A52843 |
| PMID: | 20961644 |
| Source: | J Hepatol |
| Title: | Activation of p53 enhances apoptosis and insulin resistance in a rat model of alcoholic liver disease. |
| Abstract: | BACKGROUND & AIMS: Chronic ethanol consumption in the Long-Evans (LE) rat has been associated with hepatic p53 activation, and inhibition of the insulin/PI3K/AKT signal transduction cascade due to increased expression of PTEN. We hypothesize that p53 activation and altered insulin signaling may influence the susceptibility of rats to ethanol-induced liver damage. Furthermore, p53 not only activates programmed cell death pathways and suppresses hepatocellular survival signals, but also promotes gluconeogenesis to increase systemic insulin resistance due to a novel metabolic function. METHODS: Fischer (F), Sprague-Dawley (SD) and LE rats were fed ethanol-containing or control liquid diet for 8 weeks. Histopathological and biochemical changes were assessed. RESULTS: Here, we demonstrate that chronic ethanol feeding in rats promotes p53 activation, hepatic steatosis, oxidative stress, PUMA, and PTEN expression, which contribute to hepatocellular death and diminished insulin signaling in the liver. Such changes are pronounced in the LE, less prominent in SD, and virtually absent in the F rat strain. More importantly, there is activation of Tp53-induced glycolysis and apoptosis regulator (TIGAR) in the ethanol-fed LE rat. This event generates low hepatic fructose-2,6-bisphosphate (Fru-2,6-P₂) levels, reduced lactate/pyruvate ratio and may contribute to increased basal glucose turnover and high residual hepatic glucose production during euglycemic hyperinsulinemic clamp. CONCLUSIONS: p53 activation correlates with the susceptibility to ethanol-induced liver damage in different rat strains. p53 not only orchestrates apoptosis and suppresses cell survival, but by activating TIGAR and decreasing hepatic Fru-2,6-P₂) levels it promotes insulin resistance and therefore, contributes to the metabolic abnormalities associated with hepatic steatosis. |
| DOI: | 10.1016/j.jhep.2010.08.007 |
| Strategy ID | Therapy Strategy | Synonyms | Therapy Targets | Therapy Drugs | |
|---|---|---|---|---|---|
| S01 | Improve insulin resistance | insulin sensitizer; insulin resistance; glucose tolerance | Biguanide: increases 5-AMP activated protein kinase signaling; SGLT-2 inhibitor; Thiazalidinedione: selective PPAR-γ agonists; GLP-1 agonist | Metformin; Empagliflozin; Canagliflozin; Rosiglitazone; Pioglitazone; Liraglutide | Details |
| S04 | Anti-oxidative stress | oxidative stress | α-tocopherol: antioxidant | Vitamin E | Details |
| S13 | Anti-apoptosis | hepatocyte apoptosis; hepatic autophagy; apoptosis | Pan-caspase inhibitor | Emricasan | Details |
| Target ID | Target Name | GENE | Action | Class | UniProtKB ID | Entry Name |
|---|
| Diseases ID | DO ID | Disease Name | Definition | Class | |
|---|---|---|---|---|---|
| I05 | 9352 | Type 2 diabetes mellitus | A diabetes that is characterized by chronic hyperglycaemia with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion, insulin action, or both. A diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. http://en.wikipedia.org/wiki/Diabetes, http://en.wikipedia.org/wiki/Diabetes_mellitus_type_2 | disease of metabolism/inherited metabolic disorder/ carbohydrate metabolic disorder/glucose metabolism disease/diabetes/ diabetes mellitus | Details |
| Drug ID | Drug Name | Type | DrugBank ID | Targets | Category | Latest Progress | |
|---|---|---|---|---|---|---|---|
| D199 | L-alanine | Chemical drug | DB00160 | KYNU | -- | Failed in clinical trials | Details |
| D142 | Fructose | Chemical drug | DB04173 | -- | Intravenous nutrition drug | Under clinical trials | Details |
| D080 | Citrulline | Chemical drug | DB00155 | -- | -- | Under clinical trials | Details |
| D018 | Aspirin | Chemical drug | DB00945 | AKR1C1 inhibitor; PCNA downregulator | Enhance lipid metabolism | Under clinical trials | Details |
| D083 | CLA | Chemical drug | DB01211 | KCNH2; SLCO1B1; SLCO1B3 | -- | Under clinical trials | Details |
| D182 | Insulin | Biological drug | DB00030 | INSR agonist; CPE modulator&product of | -- | Under clinical trials | Details |
| D316 | S-adenosyl-L-methionine | Chemical drug | DB00118 | GNMT cofactor | Antiviral | Under clinical trials | Details |