Effects of low-intensity pulsed ultrasound on hematopoietic function in rats after combined chemotherapy with doxorubicin and cyclophosphamide

Abstract

To investigate the effect of low-intensity pulsed ultrasound (LIPUS) on hematopoietic function in rats after combined chemotherapy with doxorubicin and cyclophosphamide. Eighty rats were randomized into control group and LIPUS group (n=40) for treatment with intraperitoneal injection of doxorubicin (2 mg/kg)+cyclophosphamide (20 mg/kg) for 4 consecutive days and continuous irradiation with LIPUS for 7 days following the injections, respectively. The white blood cells, red blood cells and platelets counts in each group were measured at 0, 4, 7, 9, 11, 14 and 18 days after the start of drug administration. The pathological sections of the bone marrow were examined at 0, 4 and 11 days, and the flow cytometry was performed for detecting the cell apoptosis; qPCR was performed for detecting the expressions of SCF, ICAM-1, and VCAM-1 mRNAs, and ELISA was used to detect the expressions of IL-3 and GM-CSF. The white blood cell count was significantly higher in LIPUS group than in the control group (P < 0.05). Histopathological examination of the bone marrow revealed significantly increased hematopoietic tissue in LIPUS group (P < 0.05). Flow cytometry demonstrated an obviously lower cell apoptosis rate in the bone marrow in LIPUS group than in the control group (P < 0.05). Compared with those in the control group, the mRNA expression levels of ICAM-1 and VCAM-1 as well as the protein levels of IL-3 and GM-CSF were significantly increased in LIPUS group (P < 0.05). LIPUS can alleviate the hematopoietic damage after combined chemotherapy with doxorubicin with cyclophosphamide probably by increasing the expressions of ICAM- 1, VCAM-1, IL- 3, and GM-CSF.