[Effect and Mechanism of Epimedium Polysaccharide on Bone Marrow Hematopoietic Function and Th17/Treg Balance in Aplastic Anemia].

Objective: To observe the effects of Epimedium polysaccharides (EPS) on bone marrow hematopoietic function and Th17/Treg balance in aplastic anemia (AA) mice, and preliminarily explore its therapeutic mechanism.

Methods: Forty BALB/C mice were randomly divided into control (control), model (model), stanozolol (stanozolol) and epimedium polysaccharide (EPS) group, with 10 mice in each group. Except for the control group, Acetophenazine, Gy irradiation and cyclophosphamide triple application were used to establish AA models for the other groups. After the model was established, the stanozolol group was intragastrically administered with 4 mg/kg stanozolol suspension, the EPS group was intragastrically administered with 100 mg/kg epimedium polysaccharide, while the control group and the model group were given an equal volume of 0.9% sodium chloride solution by gavage once a day, for 14 consecutive days. The automatic animal blood analyzer was used to detect the changes in peripheral blood hemoglobin (Hb), red blood cells (RBC), white blood cells (WBC) and platelets (PLT), flow cytometry was used to detect the proportion of Treg and Th17 cells, the levels of interleukin 2 (IL-2), interleukin 11 (IL-11) and tumor necrosis factor α (TNF-α) were detected by ELISA, the number of nucleated bone marrow cells was counted, HE staining and immunohistochemical staining were used to detect the number, the proliferation and apoptosis of bone marrow cells, Western blot was used to detect the expression of signal transducer and activator of transcription 3 (STAT3), retinoic acid receptor-related orphan receptor γ (RORγt), transducer and activator of transcription 5 (STAT5) and fork head transcription factor 3 (Foxp3).

Results: Compared with the model group, the levels of Hb, RBC, WBC and PLT in the peripheral blood of mice in stanozolol and EPS group significantly increased, the proportion of Th17 cells was significantly reduced, and the proportion of Treg cells significantly increased. The levels of IL-2 and TNF-α in serum were significantly reduced (P<0.05), the level of IL-11 significantly increased (P<0.05), the number of bone marrow nucleated cells significantly increased (P<0.05), the positive rate of Ki-67 significantly increased (P<0.05) and the positive rate of Caspase-3 was significantly reduced (P<0.05). At the same time, the protein expression of STAT3 and RORγt significantly decreased, and the protein expression of STAT5 and Foxp3 increased, the difference showed statistically significant (P<0.05).

Conclusion: EPS can promote the recovery of bone marrow hematopoietic function in AA mice and improve Th17/Treg imbalance, the mechanism may be related to the inhibition of STAT3/RORγt expression and promotion of STAT5/Foxp3 expression.