The Biomarker TCONS_00016233 Drives Septic AKI by Targeting the miR-22-3p/AIFM1 Signaling Axis
MOLECULAR THERAPY-NUCLEIC ACIDS
Authors: Zhang, Pan; Yi, Lei; Qu, Siyuan; Dai, Jinzhong; Li, Xiaozhou; Liu, Bohao; Li, Huiling; Ai, Kai; Zheng, Peilin; Qiu, Shuangfa; Li, Yijian; Wang, Yinhuai; Xiang, Xudong; Chai, Xiangping; Dong, Zheng; Zhang, Dongshan
Abstract
The prediction of mortality for septic acute kidney injury (AKI) has been assessed by a number of potential biomarkers, including long noncoding RNAs (lncRNAs). However, the validation of lncRNAs as biomarkers, particularly for the early stages of septic AM, is still warranted. Our results indicate that the lncRNA TCONS_00016233 is upregulated in plasma of sepsis-associated non-AKI and AKI patients, but a higher cutoff threshold (9.5 x 10(5), copy number) provided a sensitivity of 71.9% and specificity of 89.6% for the detection of AKI. The plasma TCONS_00016233 was highly correlated with serum creatinine, tissue inhibitor metalloproteinase-2 (TIMP-2), insulin-like growth factor binding protein-7 (IGFBP7), interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), C-reactive protein (CRP), and urinary TCONS_00016233. Lipopolysaccharide (LPS) induced the expression of lncRNA TCONS_00016233 via the Toll-like receptor 4 (TLR4)/p38 mitogen-activated protein kinase (MAPK) signal pathway in human renal tubular epithelial (HK-2) cells. Furthermore, TCONS_00016233 mediates the LPS-induced HK-2 cell apoptosis and the expression of IL-1 beta and TNF-alpha. Mechanistically, TCONS_00016233 acts as a competing endogenous RNA (ceRNA) to prevent microRNA (miR)-22-3p-mediated downregulation of the apoptosisinducing factor mitochondrion-associated 1 (AIFM1). Finally, overexpression of TCONS_00016233 is capable of aggravating the LPS- and cecal ligation and puncture (CLP)-induced septic AKI by targeting the miR-22-3p/AIFM1 axis. Taken together, our data indicate that TCONS_00016233 may serve as an early diagnosis marker for the septic AM, possibly acting as a novel therapeutic target for septic AKI.
Apoptosis-Inducing Factor (AIF) in Physiology and Disease: The Tale of a Repented Natural Born Killer
EBIOMEDICINE
Authors: Bano, Daniele; Prehn, Jochen H. M.
Abstract
Apoptosis-inducing factor (AIF) is a mitochondrial oxidoreductase that contributes to cell death programmes and participates in the assembly of the respiratory chain. Importantly, AIF deficiency leads to severe mitochondrial dysfunction, causing muscle atrophy and neurodegeneration in model organisms as well as in humans. The purpose of this review is to describe functions of AIF and AIF-interacting proteins as regulators of cell death and mitochondrial bioenergetics. We describe how AIF deficiency induces pathogenic processes that alter metabolism and ultimately compromise cellular homeostasis. We report the currently known AIFM1 mutations identified in humans and discuss the variability of AIFM1-related disorders in terms of onset, organ involvement and symptoms. Finally, we summarize how the study of AIFM1-linked pathologies may help to further expand our understanding of rare inherited forms of mitochondrial diseases. (C) 2018 German Center for Neurodegenerative Diseases (DZNE). Published by Elsevier B.V.