Objective: To observe the curative efficacy of Busui Shengxue granule in treating chronic aplastic anemia (CAA) and its effect on protein expressions of Ras homologous members (Rho)-guanosine triphosphate (GTPase)

such as cell division cycle 42 (CDC42)

Ras-related C3 botulinum toxinsubstrate (Rac) and Ras homologous member A (Rho A) in bone marrow mononuclear cells (BMNC). Method: Totally 134 CAA patients were randomly divided into the test group (67 cases) and the control group (67 cases)

and another 20 healthy volunteers were assigned into the normal control group. The test group was treated with Busui Shengxue granule

and the control group was treated with Zaizao Shengxue tablet;both groups were treated for 6 months. The changes in the clinical curative effect

score of traditional Chinese medicine (TCM) clinical symptoms

curative effect of TCM syndromes

peripheral blood and bone marrow hyperplasia degree were observed. The protein expressions of Rho-GTP-related enzymes (CDC42

Rho A and Rac) in BMNC of CAA patients were detected by Western-blot. Result: The test group showed better clinical curative effect and TCM syndrome curative effect than the control group (P <0.05). After the treatment

the average score of TCM clinical symptoms and peripheral blood of the two groups were significantly improved (P <0.05). The average score of TCM symptoms

white blood cell count (WBC) and hemoglobin (HGB) of the test group was better than that of the control group (P <0.05)

but with no significant difference in the platelet count (PLT) between the two groups. The two groups showed no significant difference in the improvement of the bone marrow. Before the treatment

both groups showed lower relevant protein expressions of CDC42

Rho A and Rac the normal control group (P <0.05)

whereas after the treatment

both groups showed significant increases in the relevant protein content of CDC42 and Rho A (P <0.05)

but with no notable change in Rac expression in the test group compared with that before the treatment. After the treatment

the expressions of CDC42

Rho A and Rac in the two groups were still lower than that in the normal control group (P <0.05)

and the expressions of CDC42 and Rac in the test group were better than that in the control group. Conclusion: Busui Shengxue granule has a significant effect in treating CAA

and can improve the hematopoietic function of bone marrow of patients with CAA. The abnormal expressions of Rho A

CDC42 and Rac in BMNC of CAA patients suggested that Rho-GTPases may be closely related with the pathogenesis of CAA. Busui Shengxue granule may improve hematopoietic stem cells

hematopoietic microenvironment and hematopoietic function of bone marrows by regulating the expressions of Rho-GTPases-CDC42

Rho A and Rac.