Research Article Details
| Article ID: | A13103 |
| PMID: | 30137403 |
| Source: | J Clin Endocrinol Metab |
| Title: | Ghrelin Reduces TNF-α-Induced Human Hepatocyte Apoptosis, Autophagy, and Pyroptosis: Role in Obesity-Associated NAFLD. |
| Abstract: | Context: Human obesity is associated with increased circulating TNF-α, a proinflammatory cytokine that induces hepatocyte cell death. Objective: The potential beneficial effects of acylated and desacyl ghrelin in the progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis in obesity via the inhibition of TNF-α-induced hepatocyte apoptosis, autophagic cell death, and pyroptosis were investigated. Design, Settings, and Participants: Plasma ghrelin isoforms and TNF-α were measured in 158 participants, and hepatocyte cell death was evaluated in liver biopsies from 76 patients with morbid obesity undergoing bariatric surgery with available liver echography and pathology analysis. The effect of acylated and desacyl ghrelin on basal and TNF-α-induced cell death was determined in vitro in human HepG2 hepatocytes. Results: Circulating TNF-α and the acylated/desacyl ghrelin ratio were increased, whereas desacyl ghrelin levels were decreased in patients with obesity and NAFLD. Six months after bariatric surgery, decreased acylated/desacyl ghrelin levels, and improved hepatic function were found. Patients with obesity and type 2 diabetes showed increased hepatic ghrelin O-acyltransferase transcripts as well as an increased hepatic apoptosis, pyroptosis, and compromised autophagy. In HepG2 hepatocytes, acylated and desacyl ghrelin treatment reduced TNF-α-induced apoptosis, evidenced by lower caspase-8 and caspase-3 cleavage, as well as TUNEL-positive cells and pyroptosis, revealed by decreased caspase-1 activation and lower high-mobility group box 1 expression. Moreover, acylated ghrelin suppressed TNF-α-activated hepatocyte autophagy, as evidenced by a decreased LC3B-II/I ratio and increased p62 accumulation via AMPK/mTOR. Conclusions: Ghrelin constitutes a protective factor against hepatocyte cell death. The increased acylated/desacyl ghrelin ratio in patients with obesity and NAFLD might constitute a compensatory mechanism to overcome TNF-α-induced hepatocyte apoptosis, autophagy, and pyroptosis. |
| DOI: | 10.1210/jc.2018-01171 |
| Strategy ID | Therapy Strategy | Synonyms | Therapy Targets | Therapy Drugs | |
|---|---|---|---|---|---|
| S09 | Bariatric surgery | Metabolic surgery | -- | -- | Details |
| S13 | Anti-apoptosis | hepatocyte apoptosis; hepatic autophagy; apoptosis | Pan-caspase inhibitor | Emricasan | Details |
| S05 | Anti-inflammatory | inflammatory | Bile acid; TNF-a inhibitor; Dual PPAR-α and -δ agonists; Toll-Like Receptor; (TLR)-4 antagonist; Caspase inhibitor; ASK-1 inhibitor | Ursodeoxycholic Acid; Pentoxifylline; Elafibranor; JKB-121; Emricasan; Selonsertib; | Details |
| Target ID | Target Name | GENE | Action | Class | UniProtKB ID | Entry Name | |
|---|---|---|---|---|---|---|---|
| T01 | 5'-AMP-activated protein kinase subunit beta-1 | PRKAB1 | activator | Kinase | Q9Y478 | AAKB1_HUMAN | Details |
| T07 | Bile acid receptor | NR1H4 | agonist | Nuclear hormone receptor | Q96RI1 | NR1H4_HUMAN | Details |
| T08 | Tumor necrosis factor | TNF | inhibitor | Cytokine | P01375 | TNFA_HUMAN | Details |
| T10 | Caspase-1 | CASP1 | inhibitor | Enzyme | P29466 | CASP1_HUMAN | Details |
| T11 | Caspase-3 | CASP3 | inhibitor | Enzyme | P42574 | CASP3_HUMAN | Details |
| T18 | Acetyl-CoA carboxylase 1 | ACACA | inhibitor | Enzyme | Q13085 | ACACA_HUMAN | Details |
| 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 |
| I14 | 9970 | Obesity | An overnutrition that is characterized by excess body fat, traditionally defined as an elevated ratio of weight to height (specifically 30 kilograms per meter squared), has_material_basis_in a multifactorial etiology related to excess nutrition intake, decreased caloric utilization, and genetic susceptibility, and possibly medications and certain disorders of metabolism, endocrine function, and mental illness. https://en.wikipedia.org/wiki/Obesity | disease of metabolism/acquired metabolic disease/ nutrition disease/overnutrition | Details |
| Drug ID | Drug Name | Type | DrugBank ID | Targets | Category | Latest Progress | |
|---|---|---|---|---|---|---|---|
| D018 | Aspirin | Chemical drug | DB00945 | AKR1C1 inhibitor; PCNA downregulator | Enhance lipid metabolism | Under clinical trials | Details |
| D094 | Cysteamine | Chemical drug | DB00847 | GSS stimulant | Renal drug | Under clinical trials | Details |
| D095 | Cysteamine bitartrate | Chemical drug | DB00847 | -- | -- | Under clinical trials | Details |