Expression and significance of DHPS,an activating factor of eIF5A,in nonalcoholic fatty liver disease

Abstract

Abstract: Objective To investigate the expression and mechanism of deoxyhypusine synthase (DHPS), an activating factor of eIF5A, in high-fat (HF) diet-fed mice and nonalcoholic fatty liver disease (NAFLD) patients.Methods Immunohistochemistry, western blot and real-time polymerase chain reaction (PCR) were performed to identify the DHPS expression in both HF mice and normal diet-fed (ND) mice. Hematoxylin-eosin (H&E) and oil red staining were conducted between DHPS overexpression group and green fluorescent protein (GFP) control group to compare the degree of liver steatosis and inflammation. In addition, PCR arrays were made to find potential genes related to DHPS. Immunohistochemistry and immunofluorescence were conducted to identify the expression of DHPS in NAFLD patients and HL-7702 cell line modeled with OP 2:1. Results HF mice highly expressed DHPS (1.80 vs 0.69, P<0.05), especially in liver (13.21 vs 1.00, P<0.01) and adipose (7.97 vs 1.00, P<0.01) tissue. Mice with overexpression DHPS endured more severe hepatic steatosis compared with mice treated with GFP (2.78 vs 2.20, P<0.05), which might be correlated with Ascbg2, Irs1, iNos and IL-6. Expression of DHPS was more common in NAFLD patients than that in normal controls (1.29 vs 0.50, P<0.05). In histology, the number of DHPS-positive cells was correlated with the degree of steatosis (r=0.5927,P=0.018). HL-7702 treated with OP 2:1 showed higher expression of DHPS.Conclusion Expression of DHPS is significantly increased in HF mice, liver tissue in patients with NAFLD and HL-7702 cell line treated with OP, which suggests an important role of DHPS in the pathogenesis of NAFLD.

Key words: Eukaryotic translation initiation factor 5A, Deoxyhypusine synthase, Nonalcoholic fatty liver disease

MIAO Qi, BIAN Zhao-lian, WANG Zhao-yue, PENG Yan-shen, MA Xiong. Expression and significance of DHPS,an activating factor of eIF5A,in nonalcoholic fatty liver disease[J]. Chinese Hepatolgy, 2016, 21(4): 253-258.

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