Immunopotentiator separated from hot water extract of the seed of Benincasa cerifera Savi (Tohgashi)

Therapeutic potential of Benincasa cerifera: A review

Benincasa cerifera (Savi.), belonging to Cucurbitaceae, is an annual creepy wine that posses highm edicinal value and istraditionally used as fruit and medicine throughout India. In Indian system of medicine, its fruit is used as nutritive, tonic, diuretic, aphrodisiac, styptic, vermifuge and in various diseases and disorders like asthma, bronchitis, insanity, epilepsy, dry cough, fever, urethrorrhea, syphilis, hyperdipsia and vitiated conditions of pitta, etc. Phytochemically the plant is found to contain lupeol, β-sitosterol, cucurbitacin B, iso-vitexin, etc. It has been demonstrated to posses numerous pharmacological activities such as antiepileptic, hepatoprotective, antioxidant, analgesic, immunopotentiator and anxiolytic, etc. In the present review there is a detailed description of its botany, phytochemistry, ethno-botany and pharmacological activities.

Effect of Benincasa hispida fruits on testosterone-induced prostatic hypertrophy in albino rats

BACKGROUND

Benincasa hispida Cogn. has been used traditionally in India for the management of urinary disorders. The fruit of B hispida is used as a diuretic and the seeds have been reported to possess antiangiogenic effects in prostate cells.

OBJECTIVE

The aim of the present study was to examine the effect of petroleum ether extract, ethanolic extract, and B hispida seed oil on hyperplasia of the prostate induced by the subcutaneous administration of testosterone in rats.

METHODS

In vitro studies were performed to determine the 5α-reductase inhibitory potential of the extracts. The results of those studies paved the way for the pharmacologic screening of the extracts to assess their potential against testosterone-induced hyperplasia in rats. Nine groups containing 10 rats per group were created for this study. Hyperplasia was induced by administration of testosterone (3 mg/kg SC) for 14 days in all the groups except the vehicle-treated group. Simultaneous administration of petroleum ether extract (100 or 200 mg/kg PO), ethanolic extract (100 or 200 mg/kg PO), and B hispida seed oil (20 or 40 mg/kg PO) was conducted. A standard 5α-reductase inhibitor (ie, finasteride) was used as a positive control. The weight of the rats was recorded on day 0 (ie, day 1 of the study) and on day 14, and the influence of testosterone and test extracts on the weight of the rats was determined. On day 14, rats were euthanized; prostates were dissected out, and weighed. The rats' prostate/body weight (P/BW) ratio was then determined. Histologic examinations were performed on prostates from each group.

RESULTS

The petroleum ether extract as well as B hispida seed oil exhibited inhibition of 5α-reductase activity in in vitro studies. Ethanolic extract did not exhibit significant inhibitory potential in vitro. Further in vivo study found that testosterone treatment significantly increased the rats' P/BW ratio in all the groups except the vehicle-treated rats, and this increase in weight was significantly inhibited in rats administered petroleum ether extract (100 and 200 mg/kg PO) and B hispida seed oil (20 and 40 mg/kg PO). Ethanolic extract did not exhibit any significant activity.

CONCLUSIONS

Petroleum ether extract and B hispida seed oil inhibited testosterone-induced hyperplasia of the prostate in these rats. Further studies are needed to evaluate its effect in humans with benign prostatic hyperplasia.

In vitro and in vivo immunomodulating and immunorestorative effects of Astragalus membranaceus

Astragalus membranaceus is a common traditional Chinese medicinal plant widely used as a tonic to enhance the body's natural defense mechanisms. In this study, bioactive fractions were isolated from the roots of Astragalus membranaceus. One of these fractions, designated as AI, was found to be the most potent with respect to its mitogenicity on murine splenocytes. Effects of AI on both specific and nonspecific immunity in mouse models were examined. Results showed that AI could exhibit mitogenic and co-mitogenic activities on mouse splenocytes, both in vitro and in vivo. Experiments in human cell culture demonstrated that AI was also active on human lymphocytes. It was found that AI was mitogenic to T cell depleted population but virtually inactive on B cell depleted population. Intraperitoneal injection of AI into mice markedly augmented the antibody response to sheep red blood cells. Besides, both the influx of macrophages into the peritoneal cavity and the phagocytic activity of macrophages were found to be enhanced by AI in vivo. On the other hand, AI could significantly increase the interleukin-2 receptor expression on mouse splenocytes in vitro. In terms of immunorestorative activity, it was found that AI could restore the lymphocyte blastogenic response of the older mice to values that are normally found in the younger mice. Moreover, administration of AI in vivo could partially restore the depressed immune functions in tumour-bearing mice and cyclophosphamide-treated mice. Collectively, the results clearly showed that AI could exhibit immunomodulating and immunorestorative effects, both in vitro and in vivo.

Anti-angiogenic effect of the seed extract of Benincasa hispida Cogniaux

Benincasa hispida in Korea was used mainly diabetes and diuresis diseases. This study was carried out to evaluate anti-angiogenic effect of the seed extract of Benincasa hispida Cogniaux. Basic fibroblast growth factor (bFGF) is a potent angiogenic factor found in various tumors. In this study, we found that the seed extract of Benincasa hispida Cogniaux decreased bFGF-induced endothelial cell proliferation and tube formation in a dose-dependent manner. Besides, Benincasa hispida seed extract showed no cytotoxicity on HUVECs and normal fibroblast cells. Furthermore, the seed extract of Benincasa hispida showed a potent inhibitory effect on bFGF-induced angiogenesis in vivo. These results suggest that the seed extract of Benincasa hispida inhibits the proliferation of endothelial cells induced by bFGF, which may explain its anti-angiogenic properties.

Activation of the anti-tumor effector cells by Radix bupleuri

Radix bupleuri, the root of Bupleuri spp., Chinese medicinal herbs used for the treatment of influenza, malaria and menstrual disorders, were extracted with hot water and separated into five different fractions (RB, RBI, RBII, RBIII and RBIV) by stepwise alcohol precipitation. One of these fractions, RBI, was then fractionated into RBIa and RBIb by gel filtration using G-100 Sephadex. These two fractions were further purified into RBIai, RBIaii and RBIbi, RBIbii fractions respectively by ion-exchange chromatography using DEAE-Sephadex. Each of these fractions is a heteropolymer consisting mainly of carbohydrate and varying proportions of protein and uronic acid. RBIaii was found to show strong anti-tumor activities in sarcoma-bearing mice. Mechanistic studies showed that RBIaii exhibited a potent activating effect on the cytotoxic activity of macrophages, NK and LAK cells against tumor cells. In addition, RBIaii could increase the number of tumor infiltrating lymphocytes (TILs) in the tumor site of WEHI-164-bearing mice. Furthermore, RBIaii could induce the release of interferon-gamma by lymphocytes in vitro.

Immunomodulatory and anti-tumour polysaccharides from medicinal plants

Many Chinese medicinal plants have immunomodulatory and anti-tumour activities. Most of the anti-tumour activities of these Chinese herbs are probably due to their immunostimulating polysaccharide components. A general scheme for the isolation and purification of the bioactive polysaccharides from naturally occurring medicinal plants is described. Hot-water extraction followed by various chromatographic methods are usually used to purify the bioactive polysaccharides. The different fractions separated from Chinese medicinal plants show a range of immunomodulatory and anti-tumour activities. The analytical methods used for monosaccharide sequence determination and structural elucidation of the bioactive polysaccharides are described, as are the tests used to evaluate their immunopharmacological activities, both in vitro and in vivo. The purification, characterization and structural elucidation of immunomodulatory polysaccharides from medicinal plants may have important implications in the immunotherapy of cancer and in the treatment of various other diseases.

The immunostimulating activities of anti-tumor polysaccharides from Pseudostellaria heterophylla

We have previously shown that a mitogenic fraction (PH-I) separated from Pseudostellaria heterophylla exhibits both immunomodulatory and anti-tumor activities. In the present study, PH-I was further purified by gel filtration chromatography and the resulting three fractions (PH-I A, PH-I B and PH-I C) were assessed for their anti-tumor activity in vivo. It was found that fraction PH-I C from P. heterophylla could markedly suppress the growth of EAT cells in vivo. Mechanistic studies have shown that i.p. injection of PH-I C into mice could enhance the phagocytic activity of thioglycollate-elicited peritoneal macrophages. Moreover, PH-I C showed a potent activating effect on the cytotoxic activity of natural killer (NK) cells and alloreactive cytotoxic T cells (Tc) as well as increased the MurIL-2-induced lymphokine activated killer cell (LAK) activity in vitro. In addition, PH-I C could increase the number of tumor infiltrating lymphocytes (TILs) in the tumor site of WEHI-164-bearing mice. Finally, i.v. injection of PH-I C significantly elevated the levels of IFN-gamma and IL-4 in sera of EAT-bearing mice.

Effects of Pseudostellaria heterophylla on proliferation and differentiation of murine bone marrow cells

The incorporation of tritiated thymidine into the DNA of murine bone marrow cells could be stimulated by fraction PH-I Ba separated from the roots of Pseudostellaria heterophylla in a dose-dependent manner in vitro. Moreover, PH-I Ba could induce the differentiation of murine bone marrow cells from pluripotent haemopoietic stem cells into macrophages-like cells in vitro. Autocrine or paracrine stimulation of granulocyte-macrophage colony stimulating factor was likely to underly the induction of differentiation. Therefore, PH-I Ba was proved to be an immunostimulating agent for mouse marrow hematopoiesis and was found to be a polysaccharide. The sugar components were analyzed by Gas Liquid Chromatography of their alditol acetates.

Activation of murine peritoneal macrophages by intraperitoneal administration of a traditional Chinese herbal medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to)

Macrophage activation by a traditional Chinese herbal medicine, xiao-chai-hu-tang (Japanese name: shosaiko-to), was investigated. Intraperitoneal (i.p.) administration of shosaiko-to into (BALB/c x DBA/2)F1 mice resulted in marked activation of macrophages with respect to phagocytic and lysosomal enzyme activities (acid phosphatase and N-acetyl-beta-D-glucosaminidase) compared with the control. The maximal responses were induced by an i.p. injection of 3 mg shosaiko-to 4 days previously. Enhanced activities induced by shosaiko-to were also seen in C3H/HeJ mice, which is a non-responder strain to bacterial lipopolysaccharide (LPS). Significant macrophage accumulation in the peritoneal cavity and increased lysosomal enzyme activities were observed in mice injected with shosaiko-to. Shosaiko-to exhibited significant cytostasis-inducing activity. In addition, the administration of shosaiko-to led to a moderate expression of Ia antigen on the surface of peritoneal macrophages. These results suggest that shosaiko-to is a potent macrophage activator.