Improvement of Immune and Hematopoietic Functions by Litsea japonica Fruit Extract in Cyclophosphamide-Treated BALB/c Mice

Loss of immunity is an important cause in the pathology of infectious disease. This study investigates the effect of Litsea japonica fruit extract (LJFE) as a potential functional food on immunity and hematopoietic function in immunosuppressed BALB/c mice. Immunity-stimulating activity was observed in mice supplemented with LJFE at low (25 mg/kg), medium (50 mg/kg), and high (100 mg/kg) dosage for seven days after administration of cyclophosphamide. LJFE treatment significantly improved spleen injury score (p < 0.001) and body weight (p < 0.02) by approximately two-fold with a high dosage of LJFE (100 mg/kg). Spleen-derived lymphocyte analysis demonstrated that the numbers of clusters of differentiation (CD)4(+) and CD8(+) T-cells were notably increased by approximately two-fold (p < 0.001) with a high dosage of LJFE (100 mg/kg). In mouse splenocytes differentiated into T- and B-lymphocytes, LJFE significantly induced proliferation up to approximately 90% of control for T- (p < 0.001) and B-lymphocytes (p < 0.01) with a high dosage of LJFE (100 mg/kg). Furthermore, LJFE significantly recovered the numbers of white blood cells, red blood cells, and platelets. Enzyme-linked immunosorbent assay revealed that serum levels of immune-related cytokines, such as tumor necrosis factor-alpha, interleukin (IL)-1 beta, IL-6, IL-2, and interferon (IFN)-gamma, were notably Increased. In addition, serum levels of immunoglobulin (Ig) A, IgM, and IgG were restored by LJFE treatment. This study provides a reference to use L. japonica as a functional food ingredient to improve immunity and hematological function in humans.

Automated summary

This study investigated the effects of Litsea japonica fruit extract (LJFE) on immunity and hematopoietic function in immunosuppressed mice. The results showed that LJFE supplementation significantly improved spleen injury score, body weight, and the numbers of CD4(+) and CD8(+) T-cells. LJFE also induced proliferation of T- and B-lymphocytes and restored the levels of immune-related cytokines and immunoglobulins. This study suggests that LJFE could be used as a functional food ingredient to enhance immunity and hematological function in humans.