The regulatory roles of VEGF-Notch signaling pathway on aplastic anemia with kidney deficiency and blood stasis.

Objective: Vascular endothelial growth factor (VEGF)-Notch signaling pathway plays an important role in aplastic anemia (AA). This study aimed to evaluate the regulatory roles of VEGF-Notch signaling pathway on mesenchymal stem cells (MSCs) isolated from AA patients with kidney deficiency and blood stasis (KB) (AA MSCs).

Methods: Expression of VEGF-Notch signaling related factors, including VEGF, VEGFR, Notch-1, Jagged1, Delta-like1, and hes1 was detected in bone marrow (BM) tissues and AA MSCs by Western blot analysis. VEGF (100 ng/mL) and γ-secretase inhibitor (DAPT) (10 μM) was used to active and inhibit VEGF-Notch signaling in AA MSCs, respectively. After treatment, the proliferation, apoptosis, and adipogenic differentiation of AA MSCs was detected by Cell Counting Kit-8, flow cytometry, and Oil red O staining, respectively. Lentivirus short hairpin RNA (shRNA) were constructed to downregulate Notch-1 and VEGF in normal bone marrow mesenchymal stem cells (BMSCs), and the effects of VEGF/Notch-1 shRNA transfected BMSCs on the proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVECs) were evaluated.

Results: Significantly lower expression of VEGF, VEGFR, Notch-1, Jagged1, Delta-like1, and hes1 was revealed in AA BM tissues and AA MSCs when compared with the normal control (P < 0.05). The intervention of DAPT significantly inhibited the proliferation, and promoted the apoptosis and adipogenic differentiation of AA MSCs, while VEGF intervention exhibited opposite results (P < 0.05). Meanwhile, the proliferation, migration, and angiogenesis of HUVECs were significantly promoted by normal BMSCs, while inhibited by VEGF/Notch-1 shRNA transfected BMSCs (P < 0.05).

Conclusion: The activation of VEGF-Notch signaling pathway may be a potential therapeutic target for AA with KB.