Psoralen suppresses the phosphorylation of amyloid precursor protein (APP) to inhibit myelosuppression

Abstract

This study aims to explore the effect of Psoralen on myelosuppression, and investigating the mechanism involved in. The mesenchymal stem cells (MSCs) were treated with CTX to construct cell model of myelosuppression, and then with APP knockdown or overexpression transfection. Cell proliferation, cell apoptosis, bone growth factors, and hematopoietic growth factors were identified. The animal model of myelosuppression syndrome was established by intraperitoneal injection of cyclophosphamide (CTX) into C57BL/6 mice, and then with APP knockdown transfection. The effect of Psoralen on myelosuppression mice with APP knockdown was explored, including observin the number of hematopoietic stem cells and bone marrow MSCs, detecting the degree of osteoporosis and the number of osteoclasts. The expression of phosphorylation-amyloid precursor protein (p-APP), bone growth factors, and hematopoietic growth factors were also examined. We found that CTX treatment inhibited cell proliferation, induced cell apoptosis, promoted p-APP/APP, and inhibited the expression of aph-1 homolog A (APH-1α), presenilin enhancer-2 (PEN-2), the receptor of advanced glycation endproducts (RAGE). Psoralen pretreatment effectively promoted cell proliferation, suppressed cell apoptosis, inhibited p-APP/APP and stimulated the expression of APH-1α, PEN-2, RAGE compared with CTX treatment. After APP knockdown, cell proliferation was inhibited, and cell apoptosis was increased. The release of bone growth factors and hematopoietic growth factors was decreased. Psoralen pretreatment could reverse the effect of APP knockdown on MSCs and myelosuppression mice. In conclusion, Psoralen treatment inhibited cell apoptosis and regulated bone growth factors and hematopoietic growth factors in myelosuppression syndrome by suppressing the phosphorylation of APP.