👤 Ayano Ohtani

Chronic hepatitis B virus (HBV) infection is a major risk factor of hepatocellular carcinoma (HCC), and hepatocyte-derived host factors play important roles in HBV-associated tumor progression. Alpha-1B glycoprotein (A1BG) is a plasma glycoprotein reported to be dysregulated in multiple cancers. In this study, we investigated the functional role of A1BG in HBV-associated HCC progression. Both the HepG2 and HBV-transfected HepG2 cell lines were used to examine the biological effects of A1BG. A1BG expression was modulated using siRNA and a plasmid vector. A series of functional assays were conducted to assess cell proliferation, apoptosis, stemness, migration, and invasion. RNA microarray analysis and gene set enrichment analysis (GSEA) were performed to identify A1BG-regulated pathways. Functionally, A1BG overexpression suppressed cell proliferation, stemness, migration, invasion, and HBV products while promoting apoptosis in both HepG2 and HBV-transfected HepG2 cells. In contrast, opposite effects were shown in the event of A1BG knockdown. Moreover, A1BG expression was reduced in HBV-associated HCC tissues and correlated with advanced pathological stage and poor prognosis. RNA microarray analysis and GSEA revealed the activation of anti-HBV-related genes and suppression of FGFR1 signaling and the matrix metalloproteinase pathway in A1BG-overexpressing cells. This study provides evidence that A1BG may be a novel host factor associated with the in vitro suppression of HBV replication and HCC progression by modulating pathways related to enhanced antiviral effects, reduced proliferative capacity and stemness, and suppression of EMT. These findings suggest that A1BG is a potential therapeutic target in HBV-related HCC. Show less

Prognosis of heart failure with preserved ejection fraction (HFpEF) remains poor because of unknown pathophysiology and unestablished therapeutic strategy. This study aimed to identify a potential therapeutic intervention for HFpEF through metabolomics-based analysis. Metabolomics with capillary electrophoresis time-of-flight mass spectrometry was performed using plasma of Dahl salt-sensitive rats fed high-salt diet, a model of hypertensive HFpEF, and showed decreased free-carnitine levels. Reassessment with enzymatic cycling method revealed the decreased plasma and left-ventricular free-carnitine levels in the HFpEF model. Urinary free-carnitine excretion was increased, and the expression of organic cation/carnitine transporter 2, which transports free-carnitine into cells, was down-regulated in the left ventricle (LV) and kidney in the HFpEF model. L-Carnitine was administered to the hypertensive HFpEF model. L-Carnitine treatment restored left-ventricular free-carnitine levels, attenuated left-ventricular fibrosis and stiffening, prevented pulmonary congestion, and improved survival in the HFpEF model independent of the antihypertensive effects, accompanied with increased expression of fatty acid desaturase (FADS) 1/2, rate-limiting enzymes in forming arachidonic acid, and enhanced production of arachidonic acid, a precursor of prostacyclin, and prostacyclin in the LV. In cultured cardiac fibroblasts, L-carnitine attenuated the angiotensin II-induced collagen production with increased FADS1/2 expression and enhanced production of arachidonic acid and prostacyclin. L-Carnitine-induced increase of arachidonic acid was canceled by knock-down of FADS1 or FADS2 in cultured cardiac fibroblasts. Serum free-carnitine levels were decreased in HFpEF patients. L-carnitine supplementation attenuates cardiac fibrosis by increasing prostacyclin production through arachidonic acid pathway, and may be a promising therapeutic option for HFpEF. Show less