1,25-dihvdroxy vitamin D3 ameliorates neutrophilic asthma by regulating NLRP3/caspase-l/GSDMD signal axis / 中国药理学通报

ABSTRACT

Aim To investigate the effect of 1,25-dihydroxyvitamin D3 on airway inflammation in a mouse model of neutrophilic asthma and its influence on the NLRP3/caspase-1/GSDMD signal axis.Methods Twenty-four female SPF BALB/c mice were selected and randomly(random number table method)divided into three groupsnormal control group(A),model group(B),and intervention treatment group(C),with eight mice in each group.An animal model of mouse neutrophilic asthma was made by the method induced by chicken ovalbumin(OVA)combined with lipopolysaccharide(LPS).Group C was given 0.1% 1,25-(OH)2D3 intraperitoneal injection(4 μg·kg-1)before each OVA challenge.A noninvasive pulmonary function test was performed to assess airway responsiveness,and lung tissues and bronchoalveolar lavage fluid(BALF)were collected.HE staining and AB-PAS staining of lung tissues were performed to observe the pathological changes and airway mucus secretion.Total inflammatory cell count and classification were carried out,and the levels of IL-1β,IL-18,and IL-17 in BALF were detected.Immunohistochemistry staining of Ly-6G was done to confirm the presence of neutrophils in lung.The protein expressions of NLRP3,caspase-1,and GSDMD in lung tissues were determined by Western blot.Results The levels of IL-1β,IL-18,IL-17 in BALF in treatment group was lower than that in model group(P<0.05),and the proportion of neutrophils in BALF was lower than that in model group.Lung histology suggested that airway inflammation in treatment group was less than that in model group.In treatment group,AHR was significantly reduced; NLRP3,caspase-1,GSDMD protein expression levels were significantly lower than those in model group(P<0.05).Conclusions 1,25-dihydroxyvitamin D3 reduces airway inflammation and inflammatory cytokine secretion in mice with neutrophil asthma,and inhibits the expression of NLRP3,caspase-1 and GSDMD in lung.1,25-dihydroxyvitamin D3 may improve neutrophilic asthma by regulating the NLRP3/caspase-1/GSDMD signal axis.