| 1. |
- Fucho, Raquel, et al.
(författare)
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ASMase regulates autophagy and lysosomal membrane permeabilization and its inhibition prevents early stage non-alcoholic steatohepatitis
- 2014
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Ingår i: Journal of Hepatology. - : Elsevier. - 0168-8278 .- 1600-0641. ; 61:5, s. 1126-1134
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Tidskriftsartikel (refereegranskat)abstract
- Background and Aims: Acid sphingomyelinase (ASMase) is activated in non-alcoholic steatohepatitis (NASH). However, the contribution of ASMase to NASH is poorly understood and limited to hepatic steatosis and glucose metabolism. Here we examined the role of ASMase in high fat diet (HFD)-induced NASH. Methods: Autophagy, endoplasmic reticulum (ER) stress and lysosomal membrane permeabilization (LMP) were determined in ASMase(-/-) mice fed a HFD. The impact of pharmacological ASMase inhibition on NASH was analyzed in wild type mice fed a HFD. Results: ASMase deficiency determined resistance to hepatic steatosis mediated by a HFD or methionine-choline deficient diet. ASMase(-/-) mice were resistant to HFD-induced hepatic ER stress, but sensitive to tunicamycin-mediated ER stress, indicating selectivity in the resistance of ASMase(-/-) mice to ER stress and steatosis. Autophagic flux, determined in the presence of rapamycin and/or chloroquine, was lower in primary mouse hepatocytes (PMH) from ASMase(-/-) mice and accompanied by increased p62 levels, suggesting autophagic impairment. Moreover, autophagy suppression by chloroquine and brefeldin A caused ER stress in PMH from ASMase(+/+) mice but not in ASMase(-/-) mice. ASMase(-/-) PMH exhibited increased lysosomal cholesterol loading, decreased LMP and apoptosis resistance induced by 0-methylserine dodecylamide hydrochloride or palmitic acid, effects that were reversed by decreasing cholesterol levels by oxysterol 25-hydroxycholesterol. In vivo pharmacological ASMase inhibition by amitriptyline, a widely used tricyclic antidepressant, protected wild type mice against HFD-induced hepatic steatosis, fibrosis, and liver damage, effects indicative of early-stage NASH, Conclusions: These findings underscore a critical role for ASMase in diet-induced NASH and suggest the potential of amitriptyline as a treatment for patients with NASH.
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| 2. |
- Caliz, Rafael, et al.
(författare)
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Gender-Specific Effects of Genetic Variants within Th1 and Th17 Cell-Mediated Immune Response Genes on the Risk of Developing Rheumatoid Arthritis
- 2013
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- The present study was conducted to explore whether single nucleotide polymorphisms (SNPs) in Th1 and Th17 cell-mediated immune response genes differentially influence the risk of rheumatoid arthritis (RA) in women and men. In phase one, 27 functional/tagging polymorphisms in C-type lectins and MCP-1/CCR2 axis were genotyped in 458 RA patients and 512 controls. Carriers of Dectin-2(rs4264222T) allele had an increased risk of RA (OR = 1.47, 95% CI 1.10-1.96) whereas patients harboring the DC-SIGN(rs4804803G), MCP-1(rs1024611G), MCP-1(rs13900T) and MCP-1(rs4586C) alleles had a decreased risk of developing the disease (OR = 0.66, 95% CI 0.49-0.88; OR = 0.66, 95% CI 0.50-0.89; OR = 0.73, 95% CI 0.55-0.97 and OR = 0.68, 95% CI 0.51-0.91). Interestingly, significant gender-specific differences were observed for Dectin-2(rs4264222) and Dectin-2(rs7134303): women carrying the Dectin-2(rs4264222T) and Dectin-2(rs7134303G) alleles had an increased risk of RA (OR = 1.93, 95% CI 1.34-2.79 and OR = 1.90, 95% CI 1.29-2.80). Also five other SNPs showed significant associations only with one gender: women carrying the MCP-1(rs1024611G), MCP-1(rs13900T) and MCP-1(rs4586C) alleles had a decreased risk of RA (OR = 0.61, 95% CI 0.43-0.87; OR = 0.67, 95% CI 0.47-0.95 and OR = 0.60, 95% CI 0.42-0.86). In men, carriers of the DC-SIGN(rs2287886A) allele had an increased risk of RA (OR = 1.70, 95% CI 1.03-2.78), whereas carriers of the DC-SIGN(rs4804803G) had a decreased risk of developing the disease (OR = 0.53, 95% CI 0.32-0.89). In phase 2, we genotyped these SNPs in 754 RA patients and 519 controls, leading to consistent gender-specific associations for Dectin-2(rs4264222), MCP-1(rs1024611), MCP-1(rs13900) and DC-SIGN(rs4804803) polymorphisms in the pooled sample (OR = 1.38, 95% CI 1.08-1.77; OR = 0.74, 95% CI 0.58-0.94; OR = 0.76, 95% CI 0.59-0.97 and OR = 0.56, 95% CI 0.34-0.93). SNP-SNP interaction analysis of significant SNPs also showed a significant two-locus interaction model in women that was not seen in men. This model consisted of Dectin-2(rs4264222) and Dectin-2(rs7134303) SNPs and suggested a synergistic effect between the variants. These findings suggest that Dectin-2, MCP-1 and DC-SIGN polymorphisms may, at least in part, account for gender-associated differences in susceptibility to RA.
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| 3. |
- Lambert, Jean-Charles, et al.
(författare)
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The CALHM1 P86L Polymorphism is a Genetic Modifier of Age at Onset in Alzheimer's Disease : a Meta-Analysis Study
- 2010
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Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 22:1, s. 247-255
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Tidskriftsartikel (refereegranskat)abstract
- The only established genetic determinant of non-Mendelian forms of Alzheimer's disease (AD) is the epsilon 4 allele of the apolipoprotein E gene (APOE). Recently, it has been reported that the P86L polymorphism of the calcium homeostasis modulator 1 gene (CALHM1) is associated with the risk of developing AD. In order to independently assess this association, we performed a meta-analysis of 7,873 AD cases and 13,274 controls of Caucasian origin (from a total of 24 centers in Belgium, Finland, France, Italy, Spain, Sweden, the UK, and the USA). Our results indicate that the CALHM1 P86L polymorphism is likely not a genetic determinant of AD but may modulate age of onset by interacting with the effect of the epsilon 4 allele of the APOE gene.
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