Effect of dexamethasone on acute respiratory distress syndrome induced by the H5N1 virus in mice

Abstract

Glucocorticoids are widely used in the treatment of different inflammatory diseases. The present study was performed to investigate the effect of dexamethasone (DEX) on acute respiratory distress syndrome (ARDS) induced by the H5N1 viral infection in mice.BALB/c mice, 6-8 weeks old, were divided into three groups with 80 mice in each. The infected group and the DEX-treated infected group were inoculated intranasally with 1610 2 50% mouse infectious dose of A/Chicken/Hebei/108/2002 (H5N1) viruses, with daily intraperitoneal injections of PBS, or 2.5 mg?kg -1 DEX at days 3-14 post inoculation, respectively. The control group received noninfectious allantoic fluid and a daily intraperitoneal injection of PBS. In H5N1-infected mice, DEX treatment did not improve the mortality (17 out of 20 versus 16 out of 20 deaths in the DEX-treated infected group versus the infected group), and did not alleviate clinical signs, including weight loss, decreased food intake and inactivity. There was no significant amelioration of the hypoxaemia and ARDS-associated pathological changes in DEXtreated infected mice, as assessed by blood gas analysis and histological score. Furthermore, DEX therapy did not inhibit inflammatory cellular infiltration and cytokine release (interleukin-6 and tumour necrosis factor-a) in bronchoalveolar lavage fluid induced by the H5N1 infection.In conclusion, dexamethasone treatment (2.5 mg?kg -1 ) from days 3-14 post inoculation has no beneficial effect on acute respiratory distress syndrome caused by the H5N1 infection in mice.

Acute Lung Injury with Alveolar Hemorrhage Due to a Novel Swine-Origin Influenza A (H1N1) Virus

“…2 T a b l e 1 . T h e F i n d i g s o f B r o n c h o a l v e o l a r L a v a g e F l u (13). Recently, corticosteroid therapy has been recommended for septic shock when adrenal insufficiency was demonstrated (14).…”

Redox-Active Protein Thioredoxin-1 Administration Ameliorates Influenza A Virus (H1N1)-Induced Acute Lung Injury in Mice

“…The occurrence of influenza pneumonia was documented histologically in mice subjected to H1N1 inoculation in this study. The H1N1-inoculated control mice presented characteristic changes of acute lung injury: diffuse edema and inflammatory cellular infiltration in alveoli and interstitium of the lung, hemorrhage, and thickened airways (20). Particularly, the lung injury score remained at high levels at 24, 72, and 120 hr after inoculation.…”

“…Sections (4-μm slices) including a cut at the hilus were stained with hematoxylin and eosin for light microscopy. The histological examination procedure was similar to that described by Xu et al (20). Four readily identifiable pathological processes were graded semiquantitatively on a scale of 0 to 4: alveolar and interstitial edema, hemorrhage, margination and infiltration of inflammatory cells, and formation of bronchiolitis: a score of 0 represented normal lung; 1 represented mild; 2 was moderate; 3 was severe; and 4 denoted very severe changes.…”

Three Cases of Avian-origin Influenza A (H7N9) Virus Infection in Zhejiang Province, China: Case Report and Literature Review

“…We recommend that neuraminidase inhibitors be administered as soon as possible. Though glucocorticoid has no beneficial effect on acute respiratory distress syndrome caused by H5N1 infection in mice (10), it still remains controversial as to whether or not methylprednisolone can be used short term in H7N9 infections to reduce the excessive inflammatory reaction associated with pneumonedema. Currently, there is no scientific basis for treatment of H7N9 with anti-infective drugs.…”