Objective To explore the effect of miR-125a-5p on thymic regulatory T cell(Treg)in mice with experimental auto-immune myasthenia gravis(EAMG).Methods The EAMG model was established by immunoinduction with murine-derived acetylcho-line receptor α subunit 97-116 peptide and randomly divided into control group and EAMG group,and the mice were subjected to Len-non scoring and low-frequency repetitive electrical stimulation experiments to evaluate the model.To further explore the effect of miR-125a-5p on Treg cells,EAMG mice were injected with negative control adenovirus and miR-125a-5p-inhibited adenovirus by tail vein injection respectively,and the experimental groups were the negative control group and miR-125a-5p inhibiting group.The mRNA expression levels of miR-125a-5p and forkhead box protein P3(Foxp3)were detected by real-time fluorescence quantitative polymer-ase chain reaction(RT-qPCR),while the protein expression level of Foxp3 was detected by Western blot.The percentage of the number of Treg cells was detected by flow cytometry,and serum concentrations of interleukin-10(IL-10)and transforming growth factor-β1(TGF-β1)were assessed using enzyme-linked immunosorbent assay(ELISA).Results The EAMG mouse model was successfully established.Compared to the control group,the EAMG group exhibited a significantly higher Lennon score,positive responses to low-frequency repetitive electrical stimulation at 5Hz,and an upregulated expression of miR-125a-5p,downregulated of Foxp3mRNA and protein,reduced percentage number of Treg cells,and decreased expression of IL-10 and TGF-β1.Upon inhibition of miR-125a-5p expression in EAMG mice,compared with the negative control group,the expression of miR-125a-5p in the miR-125a-5p inhibiting group was decreased,and the Lennon score was decreased,Foxp3mRNA and protein expression were increased,with a significant in-crease in the percentage of Treg cells and enhanced expression of IL-10 and TGF-β1,and the differences were all statistically signifi-cance(P＜0.05).Conclusion The expression of miR-125a-5p was upregulated in EAMG.Inhibition of miR-125a-5p expression led to upregulation of Foxp3,an increase in the number of Treg cells,elevated levels of IL-10 and TGF-β1,and attenuation of myas-thenia gravis symptoms in EAMG mice.These results suggest that miR-125a-5p may be involved in developing myasthenia gravis dis-ease by affecting Foxp3,leading to decreased Treg cell numbers and abnormal function.

Objective To explore the effect of miR-125a-5p on thymic regulatory T cell(Treg)in mice with experimental auto-immune myasthenia gravis(EAMG).Methods The EAMG model was established by immunoinduction with murine-derived acetylcho-line receptor α subunit 97-116 peptide and randomly divided into control group and EAMG group,and the mice were subjected to Len-non scoring and low-frequency repetitive electrical stimulation experiments to evaluate the model.To further explore the effect of miR-125a-5p on Treg cells,EAMG mice were injected with negative control adenovirus and miR-125a-5p-inhibited adenovirus by tail vein injection respectively,and the experimental groups were the negative control group and miR-125a-5p inhibiting group.The mRNA expression levels of miR-125a-5p and forkhead box protein P3(Foxp3)were detected by real-time fluorescence quantitative polymer-ase chain reaction(RT-qPCR),while the protein expression level of Foxp3 was detected by Western blot.The percentage of the number of Treg cells was detected by flow cytometry,and serum concentrations of interleukin-10(IL-10)and transforming growth factor-β1(TGF-β1)were assessed using enzyme-linked immunosorbent assay(ELISA).Results The EAMG mouse model was successfully established.Compared to the control group,the EAMG group exhibited a significantly higher Lennon score,positive responses to low-frequency repetitive electrical stimulation at 5Hz,and an upregulated expression of miR-125a-5p,downregulated of Foxp3mRNA and protein,reduced percentage number of Treg cells,and decreased expression of IL-10 and TGF-β1.Upon inhibition of miR-125a-5p expression in EAMG mice,compared with the negative control group,the expression of miR-125a-5p in the miR-125a-5p inhibiting group was decreased,and the Lennon score was decreased,Foxp3mRNA and protein expression were increased,with a significant in-crease in the percentage of Treg cells and enhanced expression of IL-10 and TGF-β1,and the differences were all statistically signifi-cance(P＜0.05).Conclusion The expression of miR-125a-5p was upregulated in EAMG.Inhibition of miR-125a-5p expression led to upregulation of Foxp3,an increase in the number of Treg cells,elevated levels of IL-10 and TGF-β1,and attenuation of myas-thenia gravis symptoms in EAMG mice.These results suggest that miR-125a-5p may be involved in developing myasthenia gravis dis-ease by affecting Foxp3,leading to decreased Treg cell numbers and abnormal function.