Induction of Interferon-Gamma (IFN-γ) and T Helper 1 (Th1) Immune Response by Bitter Gourd Extract

Abstract

ABSTRACT. Mice were inoculated intraperitoneally wih 34 different types of vegetable juices, and interferon-gamma (IFN-γ) and interleukin-4 (IL-4) were measured as markers for the induction of Th1 and Th2 cells, respectively. Serum IFN-γ level was markedly increased in mice inoculated with bitter gourd (Momordica charantia) juice, but IL-4 levels were not increased with any of the 34 vegetable juices. Testing of the various components of bitter gourd, including peel, pulp, and seed, showed that the pulp induced the highest levels of IFN-γ. Trial immunogen including the heat extract of the pulp induced specific IgG 2a antibody of the mice serum inoculated with this immunogen. These results demonstrate that bitter gourd pulp induced IFN-γ production and show its promise as a means of effective immunostimulatory therapy specific for Th1 cells and IFN-γ production. KEY WORDS: bitter gourd, interferon-gamma, Th1.J. Vet. Med. Sci. 67(5): 521-524, 2005 Immune function in mammals is a complex and important homeostasis mechanism involving a variety of white blood cells, such as B cells, T cells, natural killer (NK) cells, and phagocytes (macrophages and neutrophils). Recent studies have shown the importance of the balance of T helper 1 (Th1) and T helper 2 (Th2) cells in the host immune response to infection [11,14,15]. Normal mice usually have low susceptibility to Neospora caninum, but the interferon-gamma (IFN-γ) knockout mouse and the anti-IFN-γ antibody treated mouse are highly susceptible to infection with N. caninum [4,7]. This protozoa is an intracellular parasite, so in addition to humoral immunity mediated by antibodies and complement, activation of Th1 cellular immunity, primarily involving macrophages and neutrophils, is also important [1]. To prevent these types of intracellular parasitic infections, vaccines using parasite antigens or recombinant parasite antigens have been developed. However, these vaccines with only antigens are often insufficiently effective, so supplemental immune therapy with substances capable of inducing Th1 cellular immunity is necessary [5].Plant derived substances are often recognized as highly "foreign" by the host immune system. In other words, plant derived substances, by virtue of local accumulation and increase in immune cells, can have immunostimulatory effects [10]. In addition to parasite derived antigens in vaccines to control intracellular parasites, the use of immunostimulatory substances to control Th1 or Th2 cellular responses can dramatically increase the effectiveness of these vaccines.Therefore, we have focused on finding plant substances, particularly those of vegetables, capable of non-specifically inducing Th1 and Th2 cells.Experimental animals, 5-week-old female ddY mice, were purchased from Saitama Experimental Animal Supply Co. (Saitama, Japan).For the preparation of Propionibacterium acnes suspension, P. acnes was incubated in brain heart infusion broth (containing 0.03% L-cysteine and 0.03% Tween 80) (Difco, U.S.A.) by stationary culture at 37°C for 24 h...

Suppressive effects of wild bitter gourd (Momordica charantia Linn. var. abbreviata ser.) fruit extracts on inflammatory responses in RAW 264.7 macrophages

“…decreases prostaglandin E 2 (PGE 2 ), interleukin (IL)-7 and tumor necrosis factor-␣ and increases transforming growth factor-␤ and IL-10 secretion in RAW 264.7 macrophages, Caco-2 cells and THP-1 cells (Huang and Wu, 2002;Manabe et al, 2003;Kobori et al, 2006). In in vivo studies, feeding mice the fruit of bitter gourd effectively enhanced T helper 2 hormonal responses (Manabe et al, 2003) and T helper 1 cellular immunity (Ike et al, 2005). Recently, several phytochemicals with the health benefits of bitter gourd have been isolated and studied (Husain et al, 1994;Xie et al, 1994Xie et al, , 1998Murakami et al, 2001).…”

Induction of hepatocyte growth factor production in human dermal fibroblasts and their proliferation by the extract of bitter melon pulp

“…Immunosuppressive and immunostimulating activities of bitter melon or its constituents have also been reported [37]. Prompted by the results of studies showing that the bitter melon extract augmentated cytokine secretion, we examined effects of the extract on HGF production.…”

Complementary use of topical bitter melon for atopic dermatitis

“…It may modulate anti-inflammatory cytokines, as studies show that the pulp upregulates interferon-γ in mice, 7 and transforming growth factor-β and interleukin-10 in vitro. 8 It has been shown to have anti-staphylococcal activity in vitro.…”