Immunostimulating effects of extract of Acanthopanax sessiliflorus

Abstract

As malfunction/absence of immune cells causes a variety of immunosuppressive disorders and chemical synthetic drugs for curing these diseases have many adverse effects, vigorous studies are being conducted. The Acanthopanax family has been used as traditional medicines for gastric ulcer, diabetes, etc. and culinary materials in East-South Asia. In this study, the immunostimulating properties of A. sessiliflorus were evaluated. A. sessiliflorus increased not only the splenocyte number but also immune-related cytokines such as TNF-α. However, it could not upregulate the expressions of IFN-γ and IL-2. A. sessiliflorus increased the swimming time, and comparison of organ weights relative to body weights for immune-related organs such as the spleen and thymus after a forced swim test showed that it could recover the spleen and thymus weights. It also increased the expression of TNF-α and slightly increased the concentration of IFN-γ but not IL-2. From the results, we concluded that as A. sessiliflorus has not only a host defense effect but also a stress-ameliorating property, further study it will be a promising material of immunostimulating material.

Fig. 1.

Effect of Acanthopanax sessiliflorus on splenocyte proliferation. A. sessiliflorus induced splenocytes proliferation (up to 213%) in the 300 mg/kg/day A. sessiliflorus treatment. After collection, splenocytes were seeded on a 96-well plate, and A. sessiliflorus (0, 1, 10, 100, or 250 µg/ml), LPS (10 µg/ml), or Con A (2.5 µg/ml) was added. Cells were incubated in a CO₂ incubator (5% at 37°C) under humidified conditions for 24 h and then the proliferation rate was assessed. ^{a, b, c, d, e, f}Values in the same row with different superscripts are significantly different, P<0.05. Data are shown as the mean ± SE (n=3).

Fig. 2.

Effect of Acanthopanax sessiliflorus on the concentration of TNF-α, IFN-γ, and IL-2 in the splenocyte. The concentration of TNF-α in the 250 µg/ml A. sessiliflorus treatment was upregulated to 953.30 ± 44.07 pg/ml and it increased in a dose-dependent manner (A); the concentrations of IFN-γ (B) and IL-2 (C) are unchanged compared with the other groups. After collection, splenocytes were seeded on a 96-well plate, and A. sessiliflorus (0, 1, 10, 100, or 250 µg/ml), LPS (10 µg/ml), or Con A (2.5 µg/ml) was added. Cells were incubated in a CO₂ incubator (5% at 37°C) under humidified conditions for 24 h and the activation of cytokines such as TNF-α, IFN-γ, and IL-2 was analyzed. ^{a, b, c, d, e}Values in the same row with different superscripts are significantly different, P<0.05. Data are shown as the mean ± SE (n=3).

Fig. 3.

Effect of Acanthopanax sessiliflorus on the forced swim test. A. sessiliflorus increased the swimming time. The test was conducted at 1 h after A. sessiliflorus treatment on day 28, which was the final day of treatment. The animal experiment was performed using 5 groups, the normal group, which was not subjected to the forced swim test, and 4 groups, which were treated with 0, 30, 100, or 300 mg/kg/day A. sessiliflorus. Before the test, the animal was weighed, and about 10% its body weight was placed on its tail. The duration from putting the animal in the apparatus to 10 seconds after the animal stopped moving was checked and recorded. ^{a, b} Values in the same row with different superscripts are significantly different, P<0.05. Data are shown as the mean ± SE (n=7).

Fig. 4.

Effect of Acanthopanax sessiliflorus on organ weights relative to body weight. When A. sessiliflorus was administered, the spleen weight relative to the body weight recovered in a dose-dependent manner (up to 0.19 ± 0.00%) in 300 mg/kg/day A. sessiliflorus treatment group compared with 0.19 ± 0.00% in the group not subjected to the swimming test (A). The thymus weight relative to the body weight showed changes similar to those of the spleen. In the group not subjected to the swimming test, the change was 0.11 ± 0.001%; in the 300 mg/kg/day A. sessiliflorus treatment group, the change was 0.11 ± 0.01%. After the final A. sessiliflorus administration, all animals were weighed, their appearances were judge, they were anesthetized with diethyl ether, whole blood was collected through abdominal vena cava, and the animals were then sacrificed using diethyl ether. The weights of the spleen and thymus were also measured. ^{a, b, c} Values in the same row with different superscripts are significantly different, P<0.05. Data are shown as the mean ± SE (n=7).

Fig. 5.

Effect of Acanthopanax sessiliflorus on TNF-α, IFN-γ, and IL-2 in the serum of rats. The expression of TNF-α increased in a dose-dependent manner (A). A. sessiliflorus increased relatively the concentration of IFN-γ (B). The concentration of IL-2 was unchanged by A. sessiliflorus treatment. After the final A. sessiliflorus administration, all animals were weighed, their appearances were judged, they were anesthetized with diethyl ether, whole blood was collected through the vena cava, and the animals were then sacrificed with diethyl ether. TNF-α, IFN-γ, and IL-2 were analyzed with serum using a Microplate Reader. ^a,bValues in the same row with different superscripts are significantly different, P<0.05. Data are shown as the mean ± SE (n=7).