TY - JOUR
T1 - The KLB rs17618244 gene variant is associated with fibrosing MAFLD by promoting hepatic stellate cell activation
AU - Panera, Nadia
AU - Meroni, Marica
AU - Longo, Miriam
AU - Crudele, Annalisa
AU - Valenti, Luca
AU - Bellacchio, Emanuele
AU - Miele, Luca
AU - D'Oria, Valentina
AU - Paolini, Erika
AU - Maggioni, Marco
AU - Fracanzani, Anna Ludovica
AU - Alisi, Anna
AU - Dongiovanni, Paola
PY - 2021
Y1 - 2021
N2 - Background: The rs17618244 G>A β-Klotho (KLB) variant has been associated with increased risk of ballooning and inflammation in pediatric patients with metabolic associated fatty liver disease (MAFLD), by reducing KLB expression. In hepatocytes, KLB downregulation induced fat accumulation and the expression of inflammatory and lipotoxic genes. We aimed to examine firstly the impact of the KLB rs17618244 variation on liver damage in adult patients with MAFLD and secondly its effect on hepatic stellate cells (HSCs) activation. Methods: The impact of the KLB rs17618244 variant on histological liver damage was surveyed in a retrospective cohort of 1111 adult patients with MAFLD. Subgroup analysis was performed according to the presence of obesity (BMI>35; n = 708). Immortalized HSCs (LX-2) were transfected with the KLB wild type (LX-2_KLBwt), or with the mutant one carrying the rs17618244 (LX-2_KLBmut). Findings: At ordinal regression analysis the KLB rs17618244 variant was associated with hepatic fibrosis (OR 1.23, 95% C.I.1.004–1.51; p = 0.04), but not with steatosis, inflammation and ballooning. By stratifying patients according to the presence of obesity, the KLB A allele was further associated with lobular inflammation (OR 1.32, 95% C.I.1.02–1.72; p = 0.03) and cirrhosis (OR 2.51, 95% C.I.1.23–5.05; p = 0.01) Moreover, hepatic KLB expression correlated with that of fibrogenic genes. LX-2_KLBmut cells showed reduced KLB protein levels paralleled by an induction of pro-fibrogenic genes and enhanced proliferative rate. Interpretation: The KLB rs17618244 variant is associated with hepatic fibrosis, inflammation and cirrhosis mainly in obese patients with MAFLD and HSCs which carry this mutation are highly proliferative and acquire a myofibroblast-like phenotype. Funding: Ricerca Finalizzata Ministero della Salute GR-2019–12,370,172 (NP), Ricerca Corrente Fondazione IRCCS Cà Granda (PD and ALF), Ricerca Finalizzata Ministero della Salute RF-2013–02,358,319 (ALF), and Ricerca Corrente and 5 × 1000 Ministero della Salute (AA).
AB - Background: The rs17618244 G>A β-Klotho (KLB) variant has been associated with increased risk of ballooning and inflammation in pediatric patients with metabolic associated fatty liver disease (MAFLD), by reducing KLB expression. In hepatocytes, KLB downregulation induced fat accumulation and the expression of inflammatory and lipotoxic genes. We aimed to examine firstly the impact of the KLB rs17618244 variation on liver damage in adult patients with MAFLD and secondly its effect on hepatic stellate cells (HSCs) activation. Methods: The impact of the KLB rs17618244 variant on histological liver damage was surveyed in a retrospective cohort of 1111 adult patients with MAFLD. Subgroup analysis was performed according to the presence of obesity (BMI>35; n = 708). Immortalized HSCs (LX-2) were transfected with the KLB wild type (LX-2_KLBwt), or with the mutant one carrying the rs17618244 (LX-2_KLBmut). Findings: At ordinal regression analysis the KLB rs17618244 variant was associated with hepatic fibrosis (OR 1.23, 95% C.I.1.004–1.51; p = 0.04), but not with steatosis, inflammation and ballooning. By stratifying patients according to the presence of obesity, the KLB A allele was further associated with lobular inflammation (OR 1.32, 95% C.I.1.02–1.72; p = 0.03) and cirrhosis (OR 2.51, 95% C.I.1.23–5.05; p = 0.01) Moreover, hepatic KLB expression correlated with that of fibrogenic genes. LX-2_KLBmut cells showed reduced KLB protein levels paralleled by an induction of pro-fibrogenic genes and enhanced proliferative rate. Interpretation: The KLB rs17618244 variant is associated with hepatic fibrosis, inflammation and cirrhosis mainly in obese patients with MAFLD and HSCs which carry this mutation are highly proliferative and acquire a myofibroblast-like phenotype. Funding: Ricerca Finalizzata Ministero della Salute GR-2019–12,370,172 (NP), Ricerca Corrente Fondazione IRCCS Cà Granda (PD and ALF), Ricerca Finalizzata Ministero della Salute RF-2013–02,358,319 (ALF), and Ricerca Corrente and 5 × 1000 Ministero della Salute (AA).
KW - HSCS activation
KW - Liver damage
KW - MAFLD
KW - protein stability
KW - HSCS activation
KW - Liver damage
KW - MAFLD
KW - protein stability
UR - http://hdl.handle.net/10807/219752
U2 - 10.1016/j.ebiom.2021.103249
DO - 10.1016/j.ebiom.2021.103249
M3 - Article
SN - 2352-3964
VL - 65
SP - 103249-N/A
JO - EBioMedicine
JF - EBioMedicine
ER -