Diuretic activity of the ethanol and aqueous extracts of the surface layer of Poria cocos in rat

ETHNOPHARMACOLOGICAL RELEVANCE

Poria cocos Wolf (Polyporaceae) is a well-known traditional East-Asian medicinal fungus. the epidermis ("Fu-Ling-Pi" in Chinese) of the sclerotia is used as a diuretic. This study was conducted to evaluate of ethanol extract (EE) and aqueous extract (AE) of the diuretic activity of Fu-Ling-Pi in saline-loaded rats.

MATERIAL AND METHODS

The EE and AE were orally administered to rats. Urinary excretion rate, pH and electrolyte excretion were measured in the urine of saline-loaded rats.

RESULTS

Urinary excretion rates were significantly increased by the EE. The three doses of AE only produced a slight increase urinary output. The EE had little or no effect on K(+) excretion, but did indeed induce a notable excretion of Na(+), that was in agreement with the urinary excretion. The three doses of AE produced an increase Na(+) and K(+) excretion, but did not arrive at statistical significance.

CONCLUSIONS

The present study confirmed that the not aqueous but ethanol extracts of the epidermis of Poria cocos presents a remarkable diuretic effect.

Alleviating effects of dehydration under no hyperthermia on the immunomodulatory response to the polysaccharide fraction from fu-ling (Poria cocos) in male collegiate wrestlers

BACKGROUND

It is well known that dehydration can impair bodily functions. To evaluate the impact of hydration status under ambient environmental temperature on the immune system, 25 male collegiate wrestlers were recruited to undergo an experimental dehydration program.

METHODS

Thirteen subjects had controlled diets with individual energy requirements to prevent body mass loss and restricted water intake to cause 4.52% dehydration; they formed the dehydrated group (DE). These subjects developed a urine specific gravity of about 1.030 in 84 hours. Twelve other subjects had no water restriction and maintained their total body weight comprised the euhydrated group (EU). Peripheral blood monocytes (PBMNC) were isolated after dehydration to perform immune response testing by being incubated with a polysaccharide fraction from fu-ling, Poria cocos (polysaccharide fraction from Poria cocos, PCPS, 1 - 30 £g/L), to prepare a conditioned medium termed conditioned medium of PBMNC stimulated by PCPS (PCPS-MNC-CM). More PCPS (25 µg/L) was needed in the DE group to prepare the PCPS-MNC-CM, which was assayed with a growth inhibitory curve for treated U973 cells.

RESULTS

The treated U937 cells, incubated together with PCPS-MNC-CM from the DE group, exhibited a much lower nitroblue tetrazolium (NBT) positive value of (63.7 ± 4.7)%. The concentration of interferon-gamma (IFN-γ), interleukin (IL)-1β and tumor necrosis factor (TNF)-α in PCPS-MNC-CM from subjects after dehydration was much lower than in the CM from the EU group.

CONCLUSION

The immune response to PCPS in the DE group was lower than in normally hydrated subjects.

Antiproliferative and differentiating effects of polysaccharide fraction from fu-ling (Poria cocos) on human leukemic U937 and HL-60 cells

Poria cocos (PC), Fu-Ling, is an oriental fungus and has been widely used as a Chinese traditional herbal medicine for centuries. In the present study, a neutral polysaccharide fraction from PC (PC-PS) was isolated by a series of chromatographies and its effects on antiproliferation and differentiation of human leukemic cells, U937 and HL-60, were investigated in vitro. Results showed that the molecular weight of isolated PC-PS was approximately 160 kDa, as estimated by gel permeation chromatography. The conditioned medium prepared with PC-PS (15 microg/ml)-stimulated human blood mononuclear cells for 5 days (PC-PS-MNC-CM5) exhibited a potent activity in suppressing the proliferation of U937 and HL-60 cells by 87.3 and 74.7%, respectively. Furthermore, PC-PS-MNC-CM5 induced about 66.6% of the U937 cells and 49.4% of the HL-60 cells to differentiate into mature monocytes/macrophages, which also markedly expressed surface antigens of CD11b, CD14, and CD 68. The differentiated U937 and HL-60 cells displayed physiological functions such as respiratory burst and phagocytosis, while PC-PS group and control group showed insignificant effects. Interestingly, the levels of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha in PC-PS-MNC-CM were about 41 and 10 times, respectively, higher than that of control group. Antibody neutralization tests of the PC-PS-MNC-CM5 revealed that the growth-inhibitory and differentiation-inducing activities were mainly due to the elevated cytokines of IFN-gamma and TNF-alpha. It suggests that PC-PS is a biological response modifier (BRM), instead of a cytotoxic reagent, and may be a potential alternative in leukemia therapy.

A Chinese herbal medicine, fu-ling, regulates interleukin-10 production by murine spleen cells

Fu-ling is one of the most widely used Chinese herbal medicines. In this study, we investigated the regulatory effect of fu-ling on interleukin-10 (IL-10) production in vivo. Mice were i.p. administered 0.1 mg to 1.0 mg fu-ling per gram body weight daily for three days. The spleen cells were isolated and assayed for both IL-10 and immunoglobulin (Ig) production. Results indicated that the mice treated with fu-ling had significantly increased spleen cell ability to secrete IL-10. Spleen cells isolated from the mice injected with either 0.1 mg or 1.0 mg fu-ling per gram body weight also showed an increase in IL-10 mRNA expression. As IL-10 is a potent differentiation factor of B-lymphocytes, the possible effect of fu-ling on Ig production was also studied. Results indicated that fu-ling significantly induced an increase in IgG and IgA secretion by spleen cells but showed no effect on IgM secretion. Thus, fu-ling may affect the function of B-lymphocytes via stimulating IL-10 production.

Fu-Ling, a Chinese herbal drug, modulates cytokine secretion by human peripheral blood monocytes

Fu-Ling, the sclederma of Poria cocos (Schw.) Wolf, has long been used as a sedative and diuretic in traditional Chinese herbal medicine. Our study demonstrated that the substances extracted from Fu-Ling by 50% hot ethanol significantly augmented the secretion of interleukins IL-1 beta and IL-6 6 h after in vitro cultivation of human peripheral blood monocytes. The augmented effect was dose dependent. Tumour necrosis factor-alpha (TNF-alpha) secretion was also increased as the cells were treated with 0.4 mg/ml or higher doses of Fu-Ling extract. By contrast, Fu-Ling extract significantly suppressed the secretion of transforming growth factor-beta (TGF-beta) 3 h after the in vitro drug treatment. The suppressive effect was shown at doses as low as 0.2 mg/ml of Fu-Ling extract. Since Fu-Ling extract enhanced the secretion of immune stimulators (IL-1 beta, IL-6 and TNF-alpha) but suppressed the secretion of an immune suppressor (TGF-beta), the substance in 50% hot ethanol extract of Fu-Ling might have potentiated the immune response. Fu-Ling extract was further fractionated by reverse-phase column chromatography and high-performance liquid chromatography (HPLC). The components showing activity in modulating the cytokine secretion were relatively high in hydrophobicity.