Study On The Effect And Mechanism Of Anti-SIV And PRRSV In Traditional Chinese Medicine

Based on the screening results of single Chinese medicine for the treatments of swine flu,porcine reproductive and respiratory syndromes,by using swine influenza virus infected BALB/C mice model,the protective effects of the extracts of multiple Chinese herbal for the SIV infected mice and its mechanism were studied;the results were further confirmed by in vitro anti-SIV and anti-PRRSV activity of this Chinese medicine on SPF chick embryo and Marc-145 cells.The in vivo and in vitro experimental results were used to screen for Chinese medicine formula which can fight both SIV and PRRSV virus;the optimal concentration was obtained by measuring the protective effects of the Chinese medicine with different concentrations.The results showed that the weight of mice infected with SIV did not decrease much and recovered quickly by using formulas 1,4 and 7,all three formulas can significantly reduce the lung index(P<0.01)for the influenza virus subtype H1N1infected mice,for the influenza virus subtype H3N2 infected mice,although three formulas can reduce the lung index,but formula 7 showed significant difference with the control group(P<0.05).Lung histopathology showed that the lung tissue and alveolar septum in control group fractured,and alveolar cavity increased;when Gan powder was used,large range of lung tissue in Maxingshigan mice bleeded;when ribavirin was used,the lung tissue of the mice got substantial disease.However,when formulas 1,4 and 7 were used,no significant pathological changes in lung tissue were observed,alveolar septa and alveolar wall thickness were normal.These results indicated formulas 1,4 and 7exhibited inhibitory activity for H1N1 and H3N2 Subtype Swine influenza.Formulas 1,4 and 7 not only can increase the concentrations of IL-2,IL-6,IL-10,IFN-γand TNF-αin plasma,but also increase the concentration of SOD and GSH,decreasing the concentration of MDA,comparing with the control group,the differences were significant(P<0.01),but lower than that of Maxingshigan group and ribavirin group.These results suggest that through reducing the body’s inflammatory response,these three formulas can enhance body’s antioxidant capacity,antiviral ability and alleviate the lesions caused by the virus.For influenza virus subtype H1N1 infected mice,formulas 1,4 and 7 can increase the number of CD3~+,CD4~+/CD3~+and CD8~+/CD3~+,but has no effect on CD49b~+/CD3~-;for influenza virus subtype H3N2 infected mice,three medicines can regulate the contents of CD3~+,CD4~+/CD3~+,CD8~+/CD3~+and CD49b~+/CD3~-.In group of Formula 1,the value of CD3~+in is lower than the control group;in the group of formula 4,the ratio of CD49b~+/CD3~-in mice blood is much high than the model,and has big differencecomparing with control group(P<0.05),indicating that the formulas 1and 4 may play the anti-SIV role by adjusting the ratio of mouse lymph cells in vivo(need to explain the changes of lymphocyte subsets of meaning).In vitro anti SIV experiment,the formulas 1 and 4 showed the best activity comparing with the control group,and has the big difference comparing with the control group,which suggested that formulate 1 and 2,four had a direct effect on SIV.In the experiment of in vitro anti PRRSV activity,the formulate 4 showed the best protective function,its blocking effect,inhibition effect,and direct killing effect of on cell were 70.15%,72.94%and 96.13%respectively,the formula 1 exhibited weakest anti PRRSV activity.Based on the in vitro and in vivo anti-SIV activity and in vitro anti-PRRSV study,formula 4 is the best one to have anti SIV and anti-PRRSV activity.Its anti-SIV activity was came from direct defending SIV virus,decreasing the inflammatory reaction in SIV infected mice and improving mice’s antioxidant ability;its anti-PRRSV activity was came from killing the virus,preventing the cell to adsorb the virus and inhibiting the proliferation of the virus.The anti-SIV activity of formula 4 with three different concentrations(1 g/mL,0.5 g/mL and 0.25 g/mL)were evaluated,and formula 4 with 0.25 g/mL concentration showed strong protective effect on weight loss for SIV infected mice,significantly reduced the lung index of mice,had significant difference comparing with the control group(P<0.01);pulmonary histopathological observation found that the lung tissues were normal,no hemorrhage,alveolar septa and other diseases.When concentrate was 0.5 g/mL,the medicine can significantly increase the number of CD3~+,CD4~+/CD3~+and CD8~+/CD3~+,but no effect on the CD49b~+/CD3~-.