[Study on the improvement of bone marrow microenvironment by ligustrazine in immune-induced aplastic anemia mice]

To explore the effects of ligustrazine on bone marrow microenvironment and its mechanism in aplastic anemia (AA).

Each immune-induced AA mouse was gastric fed by 4 mg ligustrazine twice a day. On the 10th day, the ulnar bone marrow partial pressure of oxygen (PbO2) was determined in vivo by a PO2 sensory needle. Then the histological features, fibroblastic colony forming unit (CFU-F) yields and the adhesive function of stromal cells of the bone marrow were assayed in vitro.

The PbO2 in ligustrazine-treated group was 10.32 +/- 1.27 kPa, while in AA group was 4.32 +/- 2.86 kPa (P < 0.001). In AA group, the microvessels were expanded, broken and being stasis. The percentage of hematopoietic tissue volume was 24.9% +/- 9.6% and the CFU-F yields was 12.5 +/- 7.3/2 x 10(6) BMNC. The microvessels in ligustrazine group were more clear and intact, not being broken and had no stasis. The percentage of hematopoietic tissue volume was 52.8% +/- 15.6% and the CFU-F yields was 31.5 +/- 10.6/2 x 10(6) BMNC. In ligustrazine group, the adhesive function of stromal cell layer cultured with bone marrow nucleated cells from normal mice was 72.7% +/- 7.8%, which was not different from that in normal group (73.4% +/- 3.4%), but much higher than that in AA group (56.2% +/- 9.8%, P < 0.01).

Ligustrazine can promote the rehabilitation of bone marrow microvessels in AA mice, increasing the oxygen supply for bone marrow microenvironment, promoting the growth of stromal cells and strengthening their adhesive function. Ligustrazine enbances the bone marrow hematopoietic cells proliferation by improving their microenvironment.