adrenomedullin and Acute-Lung-Injury

The widespread endothelial damage due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may lead to a disruption of the adrenomedullin (ADM) system responsible for vascular leakage, increased inflammatory status, and microvascular alteration with multi-organs dysfunction. The aim of this study was to evaluate the role of mid-regional proadrenomedullin (MR-proADM) as a marker of SARS-CoV2 related widespread endothelial damage, clinically identified by organs damage, disease severity and mortality. Patients with SARS-CoV-2 infection has been prospectively enrolled and demographic characteristic, clinical and laboratory data has been evaluated. In the overall population, 58% developed acute respiratory distress syndrome (ARDS), 23.3% of patients died, 6.5% acute cardiac injury, 1.4% of patients developed acute ischemic stroke, 21.2% acute kidney injury, 11.8% acute liver damage, and 5.4% septic shock. The best MR-proADM cut-off values for ARDS development and mortality prediction were 3.04 and 2 nmol/L, respectively. Patients presenting with MR-proADM values ≥2 nmol/L showed a significantly higher mortality risk. In conclusion, MR-proADM values ≥2 nmol/L identify those patients with high mortality risk related to a multiorgan dysfunction syndrome. These patients must be carefully evaluated and considered for an intensive therapeutic approach.

Topics: Acute Kidney Injury; Acute Lung Injury; Adrenomedullin; Aged; Aged, 80 and over; Biomarkers; Brain Ischemia; Comorbidity; COVID-19; Female; Humans; Male; Middle Aged; Multiple Organ Failure; Protein Precursors; Severity of Illness Index

Oxidative stress and inflammation are involved in the pathogenesis of acute lung injury (ALI). Adrenomedullin (AM) is an endogenous peptide with anti-inflammatory and antioxidant properties. This study investigated that whether AM treatment may ameliorate hyperoxia-induced ALI in rats via inhibition of oxidative stress and inflammation. Rats were randomized to receive continuous intravenous infusion of AM or saline through a microosmotic pump, and then ALI was induced by exposing the animals in sealed cages >95% oxygen for 72 h. Exposure to hyperoxia caused lung injury as increased infiltration of inflammatory cells and disruption of lung architecture. AM administration markedly improved these changes. Additionally, AM administration significantly increased glutathione peroxidase and superoxide dismutase activities. Meanwhile, hyperoxia-induced increase of lipid hydroperoxide level was markedly reduced by AM treatment. Moreover, nuclear factor-kappa B-DNA-binding activity, and production of the inflammatory mediators interleukin-6, keratinocyte-derived chemokine, and matrix metalloproteinase 9, were significantly inhibited by AM treatment. AM ameliorates hyperoxia-induced ALI in rats by suppression of oxidative stress and inflammation.

Topics: Acute Lung Injury; Adrenomedullin; Animals; Chemokines; Glutathione Peroxidase; Hyperoxia; Inflammation; Interleukin-6; Lipid Peroxides; Lung; Male; Matrix Metalloproteinase 9; NF-kappa B; Oxidative Stress; Rats; Rats, Sprague-Dawley; Superoxide Dismutase

Adrenomedullin (AM) is a 52 amino acid peptide that has shown predominant anti-inflammatory activities. In the present study, we evaluated the possible therapeutic effect of this peptide in an experimental model of acute inflammation, the carrageenan- (CAR-) induced pleurisy. Pleurisy was induced by injection of CAR into the pleural cavity of mice. AM (200 ng/kg) was administered by intraperitoneal route 1 h after CAR, and the animals were sacrificed 4 h after that. AM treatment attenuated the recruitment of leucocytes in the lung tissue and the generation and/or the expression of the proinflammatory cytokines as well as the expression of the intercellular cell adhesion molecules. Moreover, AM inhibited the induction of inducible nitric oxide synthase (iNOS), thereby abating the generation of nitric oxide (NO) and prevented the oxidative and nitroxidative lung tissue injury, as shown by the reduction of nitrotyrosine, malondialdehyde (MDA), and poly (ADP-ribose) polymerase (PARP) levels. Finally, we demonstrated that these anti-inflammatory effects of AM were associated with the inhibition of nuclear factor-κB (NF-κB) activation. All these parameters were markedly increased by intrapleural CAR in the absence of any treatment. We report that treatment with AM significantly reduces the development of acute lung injury by downregulating a broad spectrum of inflammatory factors.

Topics: Acute Lung Injury; Adrenomedullin; Animals; Anti-Inflammatory Agents; Carrageenan; Male; Mice; Pleurisy