Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Published: June 2005
AI Article Synopsis
Article Abstract
While cellular responses to low oxygen (O(2)) or hypoxia have been studied extensively, the precise identity of mammalian cellular O(2) sensors remains controversial. Using murine embryonic cells lacking cytochrome c, and therefore mitochondrial activity, we show that mitochondrial reactive oxygen species (mtROS) are essential for proper O(2) sensing and subsequent HIF-1 alpha and HIF-2 alpha stabilization at 1.5% O(2). In the absence of this signal, HIF-alpha subunits continue to be degraded. Furthermore, exogenous treatment with H(2)O(2) or severe O(2) deprivation is sufficient to stabilize HIF-alpha even in the absence of cytochrome c and functional mitochondria. These results provide genetic evidence indicating that mtROS act upstream of prolyl hydroxylases in regulating HIF-1 alpha and HIF-2 alpha in this O(2)-sensing pathway.
Chronic wounds in diabetic patients experience significant clinical challenges due to compromised healing processes. Hypoxia-inducible factor-1 alpha (HIF-1α) is a critical regulator in the cellular response to hypoxia, enhancing angiogenesis and tissue restoration. Nevertheless, the cellular response to the developed chronic hypoxia within diabetes is impaired, likely due to the destabilization of HIF-1α via degradation by prolyl hydroxylase domain (PHD) enzymes.
This work aims to explore the effect of glycolysis on the replication of porcine reproductive and respiratory syndrome virus (PRRSV) in porcine alveolar macrophages (PAMs). The changes of glucose metabolism, PRRSV protein levels, PRRSV titers, and the relative expression levels of genes and proteins in PAMs were analyzed by ELISA, qPCR, virus titration, and Western blotting after PRRSV infection. The effect of hypoxia-inducible factor-1α (HIF-1α) on PRRSV replication was subsequently assessed by specific siRNAs targeting to HIF-1α.
Department of Occupational Medical and Environmental Health, Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China.
Silicosis is a fatal occupational pulmonary disease that is characterized by irreversible replacement of lung parenchyma by aberrant Exracellular matrix (ECM). Metabolic reprogramming is a crucial mechanism for fibrosis. However, how the metabolic rewiring shifts the ECM homeostasis toward overaccumulation remains unclear.
Necrotizing enterocolitis (NEC) is a devastating disease observed in premature infants, characterized by intestinal ischemia and inflammation. Hypoxia-inducible factor-1 alpha (HIF-1α), a master regulator of the cellular response to hypoxia and ischemia, plays a critical role in NEC pathogenesis. However, the precise mechanisms by which HIF-1α influences the intestines in NEC remain poorly understood.
Granulomas, organized aggregates of immune cells which form in response to (), are characteristic but not exclusive of tuberculosis (TB). Despite existing investigations on TB granulomas, the determinants that differentiate host-protective granulomas from granulomas that contribute to TB pathogenesis are often disputed. Thus, the goal of this narrative review is to help clarify the existing literature on such determinants.
