The transition from HIF-1 to HIF-2 during prolonged hypoxia results from reactivation of PHDs and HIF1A mRNA instability.

The hypoxia-inducible factors (HIF) are transcription factors that activate the adaptive hypoxic response when oxygen levels are low. The HIF transcriptional program increases oxygen delivery by inducing angiogenesis and by promoting metabolic reprograming that favors glycolysis. The two major HIFs, HIF-1 and HIF-2, mediate this response during prolonged hypoxia in an overlapping and sequential fashion that is referred to as the HIF switch.

Incorporation of curcumin extract with lemongrass essential oil into the middle layer of triple-layered films based on furcellaran/chitosan/gelatin hydrolysates - In vitro and in vivo studies on active and intelligent properties.

Triple-layered, pH-sensitive and active films based on furcellaran (FUR), chitosan (CHIT) and gelatin hydrolysates (HGEL) were obtained for the first time. Curcumin ethanol extract (CUR) enriched with lemongrass essential oil (LEO) in three concentrations was added to the middle layer of the film. SEM and AFM analysis confirmed the formation of 3 layers, and CUR-LEO was evenly dispersed in the 2nd layer.

The hypoxia-induced changes in miRNA-mRNA in RNA-induced silencing complexes and HIF-2 induced miRNAs in human endothelial cells.

The cellular adaptive response to hypoxia relies on the expression of hypoxia-inducible factors (HIFs), HIF-1 and HIF-2. HIFs regulate global gene expression changes during hypoxia that are necessary for restoring oxygen homeostasis and promoting cell survival. In the early stages of hypoxia, HIF-1 is elevated, whereas at the later stages, HIF-2 becomes the predominant form.

Functional and HRE motifs count analysis of induction of selected hypoxia-responsive genes by HIF-1 and HIF-2 in human umbilical endothelial cells.

We analyzed the effects of selective knockdown of either HIF-1α or HIF-2α on the transcriptional response to hypoxia of human umbilical endothelial cells at two time-points (2 h and 8 h) of hypoxia. We focused on 13 previously identified hypoxia-responsive genes, pre-selected to have different activation kinetics and different proportions of HRE motifs annotated to either HIF-1 or HIF-2 in open promoters - open chromatin DNase-hypersensitive sites (DHS) regions within ±1 kb of the gene start. We report that genes activated by both HIF-1 and 2 tend to be activated earlier than genes activated by HIF-1 only, which, in turn, tend to be activated earlier than genes activated by HIF-2 only.