A few studies reported an association between fibroblast growth factor-5 (FGF5) and NAFLD. We aimed to elucidate the physiologic implication of FGF5 in NAFLD and obesity. A total of 180 subjects [(24 healthy controls and 156 patients with biopsy-proven NAFLD and/or hepatic fat content (HFC) 5% or more on MRI-PDFF] were included to assess association between HFC and various metabolic factors including body fat and plasma levels of glucose, insulin, FGF5, FGF21, oxyntomodulin, incretins, and some free fatty acids (FFAs). Additionally, we analysed a subgroup of obese patients who would undergo laparoscopic sleeve gastrectomy (LSG) (n=50) to see correlation between changes in metabolic variables related to body weight (BW) and HFC before and 6 months after surgery. Plasma FGF5 correlated better with blood glucose and HFC than with total body fat, HOMR-IR, and visceral fat. In relation to plasma FFAs, both FGF5 and HFC together showed a positive correlation with plasma FFAs such as palmitic acid, linolenic acid, and arachidonic acid, but had an inverse correlation with nervonic acid, docosanoic acid, tetracosanoic acid, and hexacosanoic acid. FGF5 level showed an independent association with blood glucose and MRI-PDFF after adjusting for multiple factors. After LSG, BW decreased by an average of 24.6%, while HFC decreased from 19.5% ± 9.1% to 5.7 ± 2.9%, p <0.01). Plasma FGF5 also decreased after LSG (1625.0 ± 656.8 pg/ml vs. 966.8 ± 339.9 pg/ml, p <0.01). The amount of plasma FGF5 change showed a significant correlation with changes in HFC and blood glucose. In conclusion, our results showed that plasma FGF5 level correlated well with HFC, blood glucose, and specific plasma FFAs and also decreased with the improvement of hepatic steatosis after bariatric surgery. Further researches on the causal relationship between FGF5, glucose and lipid metabolism, and NAFLD are needed.

Disclosure

D.Lee: None. I.Park: None.

Funding

National Research Foundation of Korea (2021R1A5A2030333, 2019R1I1A2A02062305)

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