Growth hormone-releasing hormone antagonists protect against hydrochloric acid-induced endothelial injury in vitro

Growth hormone - releasing hormone in the immune system

GHRH is a neuropeptide associated with a diverse variety of activities in human physiology and immune responses. The present study reviews the latest information on the involvement of GHRH in the immune system and inflammation, suggesting that GHRH antagonists may deliver a new therapeutic possibility in disorders related to immune system dysfunction and inflammation.

Unfolded protein response suppression potentiates LPS-induced barrier dysfunction and inflammation in bovine pulmonary artery endothelial cells

The development of novel strategies to counteract diseases related to barrier dysfunction is a priority, since sepsis and acute respiratory distress syndrome are still associated with high mortality rates. In the present study, we focus on the effects of the unfolded protein response suppressor (UPR) 4-Phenylbutyrate (4-PBA) in Lipopolysaccharides (LPS)-induced endothelial injury, to investigate the effects of that compound in the corresponding damage. 4-PBA suppressed binding immunoglobulin protein (BiP) - a UPR activation marker - and potentiated LPS - induced signal transducer and activator of transcription 3 (STAT3) and extracellular signal‑regulated protein kinase (ERK) 1/2 activation. In addition to those effects, 4-PBA enhanced paracellular hyperpermeability in inflamed bovine pulmonary endothelial cells, and did not affect cell viability in moderate concentrations. Our observations suggest that UPR suppression due to 4-PBA augments LPS-induced endothelial injury, as well as the corresponding barrier disruption.

Involvement of NEK2 and NEK9 in LPS - induced endothelial barrier dysfunction

Endothelial hyperpermeability is the hallmark of severe lung injury, including acute respiratory distress syndrome. Despite the fact that Never In Mitosis A (NIMA)-related kinase 2 (NEK2) and NEK9 mediate fundamental cellular processes, our knowledge on their role in barrier function is limited. Herein we show that NEK2 and NEK9 inhibition suppresses LPS-induced paracellular hyperpermeability and myosin light chain 2 activation in endothelial cells. Moreover, the expression levels of both kinases were elevated in inflamed mouse lungs. Based on those findings, we raise the possibility that NEK2 and NEK9 may serve as novel therapeutic targets in lung inflammatory disease.