Platonin mitigates acute lung injury in haemorrhagic shock rats

Abstract

Aim of the study: Enhanced oxidative stress and inflammatory response are crucial in mediating the development of acute lung injury induced by haemorrhagic shock with resuscitation. Platonin, a potent antioxidant, possesses potent anti-inflammation capacity. We sought to elucidate whether platonin could mitigate acute lung injury in haemorrhagic shock/resuscitation rats.

Methods: Seventy-two adult male rats were randomized to receive haemorrhagic shock/resuscitation (HS), HS plus platonin (10, 50, or 100μg/kg intravenous injection immediately after resuscitation), sham instrumentation (Sham), or Sham plus platonin (100μg/kg) (n=12 in each group). Haemorrhagic shock was induced by blood drawing and mean blood pressure was maintained at 40-45mmHg for 120min. Then, resuscitation was achieved by shed blood/saline mixtures re-infusion. After monitoring for another 8h, rats were sacrificed.

Results: Arterial blood gas and histological findings, in concert with assays of leukocyte infiltration (polymorphonuclear leukocytes/alveoli ratio and myeloperoxidase activity) and lung water content (wet/dry weight ratio), confirmed that haemorrhagic shock/resuscitation caused significant lung injury. Significant increases in concentrations of inflammatory molecules (chemokine, cytokine, and prostaglandin E(2)) as well as nitric oxide and malondialdehyde in lung tissues confirmed that haemorrhagic shock/resuscitation elicited inflammatory response and imposed oxidative stress in rats. Platonin at the dosages of 50 and 100μg/kg, but not 10μg/kg, significantly attenuated the inflammatory response and oxidative stress induced by haemorrhagic shock/resuscitation. Most important, platonin at the dosages of 50 and 100μg/kg, but not 10μg/kg, significantly mitigated the lung injury induced by haemorrhagic shock/resuscitation.

Conclusions: Platonin mitigates acute lung injury in haemorrhagic shock/resuscitation rats.