Black rice bran extract (BRBE), containing various biologically active compounds, such as anthocyanin, has antioxidant activity and numerous pharmacological effects. Here, we aimed to confirm the immunostimulatory effects of BRBE in cyclophosphamide (CP)-induced immunosuppressed cells. Our results confirmed that BRBE exerted an immunostimulatory effect. In vitro, BRBE treatment enhanced cell proliferation, activity of natural killer cells and cytotoxic T lymphocytes, and production of CP-repressed cytokines, such as tumor necrosis factor-α, interferon-γ, interleukin (IL)-2, and IL-12, and immunoglobulins G and A in isolated splenocytes. Additionally, in vivo, BRBE treatment increased the number of immune cells, such as white blood cells, lymphocyte counts, mid-range absolute counts, and neutrophils in CP-induced immunosuppressed rats. Furthermore, BRBE increased the serum levels of abovementioned inflammatory cytokines and immunoglobulins in CP-induced immunosuppressed rats. In addition, BRBE protected against CP-mediated spleen and thymic tissue damage. Our findings suggest that BRBE could be potentially used as a component of functional food for immunity enhancement.

黑米糠提取物（BRBE）包含各种生物活性化合物，例如花青素，具有抗氧化活性和多种药理作用。在这里，我们旨在确认BRBE在环磷酰胺（CP）诱导的免疫抑制细胞中的免疫刺激作用。我们的结果证实，BRBE具有免疫刺激作用。在体外，BRBE治疗可增强细胞增殖，天然杀伤细胞和细胞毒性T淋巴细胞的活性，以及​​产生CP抑制的细胞因子，例如肿瘤坏死因子-α，干扰素-γ，白介素（IL）-2和IL-12。以及分离的脾细胞中的免疫球蛋白G和A。此外，在体内，BRBE治疗可增加CP诱导的免疫抑制大鼠的免疫细胞数量，例如白细胞，淋巴细胞计数，中程绝对计数和中性粒细胞。此外，BRBE可增加CP诱导的免疫抑制大鼠的上述炎症细胞因子和免疫球蛋白的血清水平。此外，BRBE可以防止CP介导的脾脏和胸腺组织损伤。我们的发现表明，BRBE可以潜在地用作功能性食品的成分，以增强免疫力。