Research Article Details

Article ID: A25988
PMID: 21233280
Source: Am J Physiol Gastrointest Liver Physiol
Title: Deficiency in myeloid differentiation factor-2 and toll-like receptor 4 expression attenuates nonalcoholic steatohepatitis and fibrosis in mice.
Abstract: Toll-like receptor 4 (TLR4) and its coreceptor, myeloid differentiation factor-2 (MD-2), are key in recognition of lipopolysaccharide (LPS) and activation of proinflammatory pathways. Here we tested the hypothesis that TLR4 and its coreceptor MD-2 play a central role in nonalcoholic steatohepatitis (NASH) and liver fibrosis in nonalcoholic fatty liver disease. Mice of control genotypes and those deficient in MD-2 or TLR4 [knockout (KO)] received methionine choline-deficient (MCD) or methionine choline-supplemented (MCS) diet. In mice of control genotypes, MCD diet resulted in NASH, liver triglycerides accumulation, and increased thiobarbituric acid reactive substances, a marker of lipid peroxidation, compared with MCS diet. These features of NASH were significantly attenuated in MD-2 KO and TLR4 KO mice. Serum alanine aminotransferase, an indicator of liver injury, was increased in MCD diet-fed genotype controls but was attenuated in MD-2 KO and TLR4 KO mice. Inflammatory activation, indicated by serum TNF-α and nictoinamide adenine dinucleotide phosphate oxidase complex mRNA expression and activation, was significantly lower in MCD diet-fed MD-2 KO and TLR4 KO compared with corresponding genotype control mice. Markers of liver fibrosis [collagen by Sirius red and α-smooth muscle actin (SMA) staining, procollagen-I, transforming growth factor-β1, α-SMA, matrix metalloproteinase-2, and tissue inhibitor of matrix metalloproteinase-1 mRNA] were attenuated in MD-2 and TLR4 KO compared with their control genotype counterparts. In conclusion, our results demonstrate a novel, critical role for LPS recognition complex, including MD-2 and TLR4, through NADPH activation in liver steatosis, and fibrosis in a NASH model in mice.
DOI: 10.1152/ajpgi.00163.2009

Strategy ID Therapy Strategy Synonyms Therapy Targets Therapy Drugs
S03 Anti-fibrosis fibrosis Angiotensin Receptor Blocker (ARB); CCR2/CCR5 antagonist; Thyroid receptor β agonist; PEGylated human FGF21 analogue; Monoclonal antibody to lysyl oxidase-like 2 (LOXL2); Galectin-3 inhibitor; FGF19 variant Losartan; Cenicriviroc; VK-2809; MGL-3196; Pegbelfermin; Simtuzumab; GR-MD-02; NGM282 Details
S04 Anti-oxidative stress oxidative stress α-tocopherol: antioxidant Vitamin E 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
T07 Bile acid receptor NR1H4 agonist Nuclear hormone receptor Q96RI1 NR1H4_HUMAN Details
T08 Tumor necrosis factor TNF inhibitor Cytokine P01375 TNFA_HUMAN Details
T09 Toll-like receptor 4 TLR4 antagonist Membrane receptor O00206 TLR4_HUMAN Details
T10 Caspase-1 CASP1 inhibitor Enzyme P29466 CASP1_HUMAN Details
T18 Acetyl-CoA carboxylase 1 ACACA inhibitor Enzyme Q13085 ACACA_HUMAN Details

Diseases ID DO ID Disease Name Definition Class

Drug ID Drug Name Type DrugBank ID Targets Category Latest Progress
D328 Serine Chemical drug DB00133 SRR Improve insulin resistance Under clinical trials Details
D075 Choline Supplement DB00122 PLD2 product of; PLD1 product of -- Under clinical trials Details
D316 S-adenosyl-L-methionine Chemical drug DB00118 GNMT cofactor Antiviral Under clinical trials Details
D199 L-alanine Chemical drug DB00160 KYNU -- Failed in clinical trials Details