ABSTRACT
OBJECTIVE To investigate the intervention effects and potential mechanism of Miao medicine Toddalia asiatica on cardiovascular damage in rats with collagen-induced arthritis （CIA） based on vitamin D （VD） and neutrophil extracellular traps （NETs）. METHODS SD rats were randomly divided into the normal group （9 rats） and the modeling group （61 rats）. CIA model was prepared by multi-point injection of type Ⅱ bovine collagen+Fisher’s incomplete adjuvant； the model rats were randomly divided into the model group， methotrexate group （positive control， 1.5 mg/kg， twice a week）， vitamin D group [pathway validation， 1 000 IU/（kg·d）， once a day]， T. asiatica low-dose， medium-dose and high-dose groups [0.54， 1.08， 2.16 g/（kg·d）， calculated by crude drug， once a day]， with 9 rats in each group； they were given relevant medicine intragastrically for 4 consecutive weeks. Arthritis index scoring was performed after modeling and before administration， and plantar thickness was measured before and after the last administration； the histopathological changes of ankle joint， heart and abdominal aorta were observed in rats； the serum contents of myeloperoxidase （MPO）， interleukin-6 （IL-6） and 25-hydroxyvitamin D3 [25（OH）D3] were detected； the expressions of peptidylarginine deiminase 4 （PAD4）， NETs markers [citrullinated histone H3（CitH3）， MPO]， VD-related indicators [vitamin D receptor （VDR）， 25-hydroxyvitamin D-1α-hydroxylase （CYP27B1）] and IL-6 were determined in cardiac tissue. RESULTS Compared with the normal group， the plantar thickness of the arthritis index increased significantly in the model group （P＜0.01）. The obvious inflammatory cell infiltration and fibrous tissue hyperplasia were found in the ankle joint， the obvious myocardial fiber （No.2019YFC171250101） vacuoles and thickening of some surrounding blood vessel walls were found in the heart tissue， and the endothelial detachment was found in the abdominal aorta. The contents of MPO and IL-6 in serum increased significantly（P＜0.01），while the level of 25（OH）D3 decreased significantly （P＜0.01）； the protein expressions of PAD4， CitH3， MPO and IL-6 in myocardial tissue up-regulated significantly （P＜0.01）， while protein expression of VDR and CYP27B1 changed to acertain extent without significance （P＞0.05）. Compared with the model group， the pathological changes of ankle joints and cardiac tissue in rats were significantly improved in administration groups， and the above indicators were generally reversed （P＜0.05 or P＜0.01）. CONCLUSIONS T. asiatica can improve rheumatoid arthritis symptoms and cardiovascular damage by inhibiting the formation of NETs and inflammatory response， the mechanism of which may be associated with the regulation of VD expression.
ABSTRACT
Objective:To study the expression and significance of neutrophil extracellular traps (NETs) in neonatal sepsis.Methods:Prospective research were used in this study. Term infants with neonatal sepsis hospitalized for the first time in the Department of Neonatology, Children's Hospital of Soochow University from June 2020 to November 2020 were selected as the sepsis group. According to a ratio of about 1∶1, term infants with mild hyperbilirubinemia who were admitted in the same period, with gestational age difference less than 1 week from those in the sepsis group, and whose parents agreed to participate in the study were selected as the control group. On admission, clinical data as well as blood samples of the two groups were collected. Levels of NETs marker citrulline histone H3-DNA (CitH3-DNA) were detected by Enzyme-linked immunosorbent assay, and circulating cell-free DNA (cfDNA) was tested by the fluorescence microplate reader. General data, white blood cell (WBC), neutrophil count (NE), platelet (PLT), C- reactive protein (CRP), blood culture, CitH3-DNA and cfDNA were compared between the two groups. The diagnostic value of CITH3-DNA and cfDNA in neonatal septicemia was analyzed by the receiver operating characteristic (ROC) curve.Results:A total of 74 infants were included in the study, including 39 cases in the sepsis group and 35 cases in the control group. CitH3-DNA and cfDNA in the sepsis group were significantly higher than those in the control group [CitH3-DNA (optical density): 0.85±0.05 vs. 0.48±0.03, cfDNA (mg/L): 0.90±0.05 vs. 0.56±0.03] ( P<0.01). There was no significant correlation between CitH3-DNA and cfDNA. The level of CitH3-DNA had no correlation with gender, gestational age, age, birth weight, WBC, NE, PLT and CRP ( P>0.05). cfDNA was positively correlated with age and NE ( P<0.05), and negatively correlated with PLT ( P<0.05). Combined with CRP, the area under the ROC curve of CitH3-DNA+CRP, cfDNA+CRP, and CitH3-DNA+cfDNA+CRP were 0.947, 0.947 and 0.970 respectively, and the sensitivity to predict neonatal sepsis were 92.3%, 84.6% and 94.9% respectively, the specificity were 94.3%, 97.1% and 100% respectively, all higher than the predictive value of each index alone. Conclusions:The plasma NETs levels increase significantly in neonatal sepsis patients, especially CitH3-DNA with a strong specificity, and can be considered as a biomarker for early diagnosis of neonatal sepsis. NETs together with CRP, could drastically improve the predictive value of neonatal sepsis.