Red Ginseng Acidic Polysaccharide Research Articles

Immune Activity of Polysaccharide Fractions Isolated from Korean Red Ginseng

Korean red ginseng (KRG)’s pharmacological efficacy and popular immunomodulatory effects have already been proven in many studies; however, the component of KRG that is effective in immune activity has not been studied before. Therefore, this study extracted and separated KRG for an immune activity comparison. In the water fraction obtained by extracting KRG powder with water, a red ginseng neutral polysaccharide (RGNP) fraction and a red ginseng acidic polysaccharide (RGAP) fraction were obtained. Each fraction was orally administered for 10 days to mice with reduced immunity, and the number of IgM antibody-forming cells (AFCs) in splenocytes was measured to compare the immune activity of the water fractions. The results showed that the RGAP fraction has the greatest number of AFCs. To set the optimal dose of the RGAP fraction, which had the highest immune activity, the AFCs, macrophage activity, and splenocyte subtype in the mice were analyzed. As a result, the number of AFCs was significantly increased in the RGAP fraction compared to RGNP. The intraperitoneal macrophage phagocytosis activity and the number of T cells, B cells, and macrophages in the spleen increased significantly. It can, therefore, be confirmed that immune activity increases by a fraction containing higher RGAP content, and we hypothesize that RGAP activates immune activity.

Structural characteristics of a red ginseng acidic polysaccharide rhamnogalacturonan I with immunostimulating activity from red ginseng

BackgroundMany researchers reported that the various immune activities of red ginseng are due to acid polysaccharides. But, the exact structural characteristics of the acidic polysaccharide in red ginseng have not been fully elucidated. Therefore, we isolated the acidic polysaccharide from red ginseng and characterized the structural property of the active moiety of this polysaccharide, which contributes to the immunostimulatory activity of red ginseng. MethodsA polysaccharide (RGP-AP-I) was purified from red ginseng via size-exclusion chromatography using Sephadex G-100. Immunostimulatary activity of RGP-AP-I was investigated via anti-complementory and macrophage stimulatory activity. The structure of RGP-AP-I was characterized by HPLC, sugar composition, β-glucosyl Yariv reagent and methylation analysis. ResultsPeritoneal macrophages stimulated using RGP-AP-I significantly augmented the production of various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factor (TNF)-α. The primary structure of RGP-AP-I was elucidated by assessing its sugar composition and methylation analysis. RGP-AP-I is a 96 kDa acidic polysaccharide, and comprises nine different monosaccharides, which mainly include sugars such as rhamnose (Rha, 9.5%), galacturonic acid (GalA, 18.4%), galactose (Gal, 30.4%), and arabinose (Ara, 35.0%). RGP-AP-I exhibited an considerable reaction with the β–glucosyl Yariv reagent, revealing the presence of arabino-β-3,6-galactan. Methylation analysis indicated that RGP-AP-I comprises 21 different glycosyl linkages, such as 3-, 4-, 6- and 3,6-linked Galp; 5-linked Araf; 2,4-linked Rhap; and 4-linked GalAp, which are characteristics of rhamnogalacturonan I (RG-I). Conclusionwe assumed that the immunostimulatory activity of RGP-AP-I may be due to the RG-I structure, which comprises a main chain with a repeating linkage unit, [→2)-Rhap-(1→4)-GalAp-(1→] and three groups of side chains such as (1→5)-linked arabinan, (1→4)-linked galactan, and arabino-β-3,6-galactan, which branch at the C(O)4 positions of Rha residues in the main chain of RGP-AP-I.

Inhibitory effect of red ginseng acidic polysaccharide from Korean red ginseng on phagocytic activity and intracellular replication of Brucella abortus in RAW 264.7 cells.

Korean red ginseng (KRG) has long been used in traditional Korean and Oriental medicine. However, the anti-bacterial mechanism and therapeutic efficiency of KGR for intracellular Brucella infection are still unclear. In this study, the bactericidal activity of Korean red ginseng acidic polysaccharide (RGAP) on Brucella (B.) abortus and its cytotoxic effects on RAW 264.7 cells were evaluated. In addition, B. abortus internalization and intracellular replication in macrophages were investigated after RGAP treatment. RGAP-incubated cells displayed a marked reduction in the adherence, internalization and intracellular growth of B. abortus in macrophages. Furthermore, decreased F-actin fluorescence was observed relative to untreated B. abortus-infected cells. Western blot analysis of intracellular signaling proteins revealed reduced ERK, JNK and p38α phosphorylation levels in B. abortus-infected RGAP-treated cells compared to the control. Moreover, elevated co-localization of B. abortus-containing phagosomes with lysosome-associated membrane protein 1 (LAMP-1) were observed in RGAP-treated cells compared with the control. Overall, the results of this study suggest that RGAP can disrupt phagocytic activity of B. abortus via suppression of mitogen-activated protein kinases (MAPKs) signaling proteins ERK, JNK and p38 levels and inhibit intracellular replication of B. abortus by enhancing phagolysosome fusion, which may provide an alternative control of brucellosis.

Molecular Mechanism of Macrophage Activation by Red Ginseng Acidic Polysaccharide from Korean Red Ginseng

Red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng, displays immunostimulatory and antitumor activities. Even though numerous studies have been reported, the mechanism as to how RGAP is able to stimulate the immune response is not clear. In this study, we aimed to explore the mechanism of molecular activation of RGAP in macrophages. RGAP treatment strongly induced NO production in RAW264.7 cells without altering morphological changes, although the activity was not strong compared to LPS-induced dendritic-like morphology in RAW264.7 cells. RGAP-induced NO production was accompanied with enhanced mRNA levels of iNOS and increases in nuclear transcription factors such as NF-κB, AP-1, STAT-1, ATF-2, and CREB. According to pharmacological evaluation with specific enzyme inhibitors, Western blot analysis of intracellular signaling proteins and inhibitory pattern using blocking antibodies, ERK, and JNK were found to be the most important signaling enzymes compared to LPS signaling cascade. Further, TLR2 seems to be a target surface receptor of RGAP. Lastly, macrophages isolated from RGS2 knockout mice or wortmannin exposure strongly upregulated RGAP-treated NO production. Therefore, our results suggest that RGAP can activate macrophage function through activation of transcription factors such as NF-κB and AP-1 and their upstream signaling enzymes such as ERK and JNK.

Anti-hyperlipidemic Effects of Red Ginseng Acidic Polysaccharide from Korean Red Ginseng

It has been reported that red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng, displays immunostimulatory and anti-tumor activities. In a follow-up study, we have carried out a study on the anti-hyperlipidemic effects of RGAP using hyperlipidemic rats acutely induced by Triton WR1339 or corn oil intravenously injected. Oral administration of RGAP (100 to 1000 mg/kg) dose-dependently reduced the serum levels of triglyceride (TG) up-regulated by Triton WR1339, an inducer of endogenous model hyperlipidemia. Moreover, RGAP treatment was shown to significantly decrease the levels of non-esterified fatty acid (NEFA) concomitant with TG reduction. However, such reduction effects were not observed in cases of total cholesterol (TC) and phospholipid levels increased under the same conditions, although there was an inhibitory tendency. Similar suppressive patterns were also seen in hepatic parameters (total lipids and TG) under the same conditions. The exogenous hyperlipidemic rat condition triggered by corn oil also supported the anti-hyperlipidemic activity of RGAP in serum and hepatic parameters of TG and NEFA. Interestingly, RGAP significantly enhanced the serum activity of lipoprotein lipase, a key hydrolytic enzyme of lipid molecules in lipoprotein, in a dose-dependent manner up to 80%, implying potential involvement of this enzyme in lowering TG and NEFA by RGAP. Therefore, our data suggest that RGAP may play an additional role in reducing hyperlipidemic conditions, which can be used as a valuable neutraceutical application for the treatment of hyperlipidemia.

Enhancement of Murine NK cell Activity in vitro by Red Ginseng Acidic Polysaccharide

The in-vitro immunomodulatory function of the activity of murine natural-killer (NK) cells induced by redginseng acidic polysaccharide (RGAP) was examined. RGAP induced the significant enhancement of NK cell activity against the Yac-1 tumor cells. The treatment of splenocytes cultured with RGAP for 16 h resulted in a significant increase in NK activity at the E:T ratio of 100:1, and in a 239 and 250% increase at 10 and l00 ㎍/㎖, respectively. We also demonstrate that RGAP treatment increased the production of interferon (IFN)-γ (17-125%) and tumor necrosis factor (TNF)-α (15-100%), suggesting that the increase in NK cell cytotoxicity could be due to the enhancement of the NK cell production of both cytokines. In addition, RGAP had a stimulating effect on lymphocyte proliferation in the presence of mitogens. Overall, these results suggest that RGAP has an immunopotentiating effect on NK cells, which can support the development of clinical studies on RGAP.

Immunomodulation of NK Cell Activity by Red Ginseng Acidic Polysaccharide (RGAP) in Ovariectomized Rats

The in-vitro immunomodulatory function of murine natural-killer (NK) cells induced by red-ginseng acidic polysaccharide (RGAP) in ovariectomized (OVX) rats was examined in this study. The IL-2-induced NK cell activity was significantly decreased in the OVX rats compared to the sham groups, but the normally induced NK cell activity was not. RGAP, however, increased the NK cell activity in both groups, and this effect involved iNOS expression. The inhibition of iNOS activity did not increase the NK cell cytotoxicity by RGAP in the OVX rats. The data that were obtained also demonstrated that the expression of iNOS was increased in the spleen of the OVX rats. These results indicate that RGAP increases the tumoricidal activity of the NK cell in the OVX rats, which is a primed or activated state of innate immune cells resulting from the changes in cytokine production induced by estrogen-deficient stress. Therefore, RGAP has a synergistic effect on the NK cell activities, which are regulated by the iNOS signals in OVX rats. This suggests that RGAP is useful for potential therapeutic strategies as a nutrient in regulating the NK cells in OVX rats.

Synergistic immunostimulating activity of pidotimod and red ginseng acidic polysaccharide against cyclophosphamide-induced immunosuppression

We investigated the synergistic effect of combined treatment with red ginseng acidic polysaccharide (RGAP) from Panax ginseng C.A. Meyer and pidotimod in cyclophosphamide-treated mice. The combination of pidotimod and RGAP restored concanavalin A-induced splenic T cell proliferation and LPS-stimulated B cell proliferation significantly. The production of nitric oxide from peritoneal macrophages was increased by the combinations. NK cell activity was increased by RGAP alone or in combination with pidotimod. A synergistic increase in the level of serum IL-12 and interferongamm was observed when the combination of the two was used. RGAP alone or in combination with pidotimod modulated the level of serum C-reactive protein to a near-normal level. These results indicate that combinations of pidotimod and RGAP are synergistic and suggest that combination therapy using pidotimod and RGAP for improving immune activity may provide an additional benefit over the use of the two drugs by themselves.

Red Ginseng Acidic Polysaccharide (RGAP) in Combination with IFN-γ Results in Enhanced Macrophage Function through Activation of the NF-κB Pathway

This study examined the effects of red ginseng acidic polysaccharide (RGAP) on macrophage-mediated cytotoxicity towards murine melanoma B16 cells. RGAP alone had no effect on killing of tumor cells. RGAP treatment increased the production of interleukin-1 (IL-1), IL-6, and nitric oxide (NO) by macrophages, whereas tumor necrosis factor (TNF-alpha) and reactive oxygen species (ROS) production were not changed by RGAP. However, treatment of macrophages with a combination of RGAP and recombinant interferon-gamma (rIFN-gamma) enhanced killing of tumor cells. In addition, the combination treatment showed marked cooperative induction of IL-1, IL-6, TNF-alpha, and NO production. Electrophoretic mobility shift assay analysis revealed that treatment of macrophages with RGAP plus rIFN-gamma induced the activation of the nuclear factor-kappa B (NF-kappaB) transcription factor. In agreement with this, the combination treatment resulted in increased NF-kappaB-p65 expression. The present results demonstrate synergistic effects on macrophage function of RGAP in combination with rIFN-gamma, and suggest that NF-kappaB plays an important role in mediating these effects. These data also support the development of clinical studies of this combination.

Inhibitory Activities of Red Ginseng Acidic Polysaccharide in Platelet Aggregation

Red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng (Panax ginseng C.A. Meyer), has been shown to have a variety of biological functions such as immunostimulating and anti-tumor activities. In the present study, we investigated whether RGAP inhibited ligand-induced platelet aggregation. The washed platelet-rich plasma was prepared from male SD rats with successive centrifugation. The platelets <TEX>$(10^8/ml)$</TEX> were preincubated with 1 mM of <TEX>$CaCl_2$</TEX> for 2 min either in the presence or in the absence of RGAP <TEX>$(10{\sim}50\;{\mu}g/ml)$</TEX> and were stimulated with collagen (2.5 <TEX>${\mu}g/ml$</TEX>) and thrombin (0.1 U/ml). RGAP dose-dependently inhibited thrombin-induced platelet aggregation with <TEX>$IC_{50}$</TEX> value of <TEX>$26.2{\pm}2.0$</TEX> <TEX>${\mu}g/ml$</TEX>. In collagen-induced platelet aggregation, RGAP inhibited the reaction with an <TEX>$IC_{50}$</TEX> value of <TEX>$31.5{\pm}3.0\;{\mu}g/ml$</TEX>. RGAP potently suppressed the intracellular calcium ion, which was stimulated by thrombin (0.1 U/ ml). Among mitogen-activated protein kinase (MAPK) subtypes, the extracellular signal-regulated kinase (ERK) 1/2 and p38 MAPK were analyzed in the present study. RGAP inhibited the phosphorylation of ERK2 and p38 MAPK, which was activated by collagen (2.5 <TEX>${\mu}g/ml$</TEX>). Finally, these results suggested that besides saponin fraction, RGAP take an important role in the preventive effect of Korean red ginseng against cardiovascular disease such as thrombosis and atherosclerosis.

Partial chemical structure and immunomodulating activities of RGAP (Red Ginseng acidic Polysaccharide) from Korean red ginseng (Panax ginseng C. A. Meyer)

Partial chemical structure and immunomodulating activities of RGAP (Red Ginseng acidic Polysaccharide) from Korean red ginseng (Panax ginseng C. A. Meyer)

홍삼에 함유된 갈변물질 및 산성다당체에 대한 연구현황

In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred In initial stage of steaming fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after steaming. Browning reaction of red ginseng occurred between min of steaming at , and browning pigments of red ginseng were mostly water soluble substances. The structural characteristics of water soluble browning reaction products(WS-BRPs) isolated from Korean red ginseng were showed the presence of hydroxyl, amide carbonyl and aliphatic methane groups. From sugar analysis it was identified that L and S-1, melanoidins isolated from red ginseng, contained two kinds of sugars, glucose and xylose, and the other melanoidin S-2 contained the previous and fructose. In order to find out pertinent methods for the acceleration of browning during ginseng processing, various treatment were made on fresh ginseng with sugars, amino acids and inorganic nitrogenous compounds and the extent of browning was measured. Among sugar tested, maltose resulted in the greatest acceleration of browning followed in decreasing order by glucose and lactose, whereas pentoses, fructose, sucrose and raffinose had negligible effect. A marked browning occurred in ginseng treated with basic amino acids, while the extent of browning was not greatly increased when ginseng was treated with aliphatic amino acids, hydroxyl amino acids, or acidic amino acids. The brown color intensity gradually increased with an increase of glucose concentration far up to 0.5M. L, S-1, and S-2 were found to have an ability to donate hydrogen to DPPH, and also they had anti-oxidative activity in the experiments of hydrogen peroxide scavenging, inhibitory activity in the formation of MDA from linoleic acid, auto oxidation of ok-brain homogenates, lipid peroxidation by the enzymatic and non-enzymatic system in liver microsome fraction, and mitochondrial fraction etc. The amounts of acidic polysaccharide(AP) in red ginseng were higher than those of wild and cultured Panax quinquefolius, Panax notoginseng as well as white ginseng (Panax ginseng). In white ginseng, the AP amount is no difference in root ages or sizes, also, the AP amount of ginseng body was similar to that of rhizome, but was higher than that of leaf and epidermis. Addition of red ginseng acidic polysaccharide(RGAP) increased production of nitric oxide(NO) and tumor necrosis factor (TNF)- in the rodent macrophage cultures, and treatment of RGAP in vivo stimulated tumoricidal activities of natural killer (NK) cells.

홍삼산성다당체 (RGAP)의 경구투여에 의한 항종양 효과

Our previous reports demonstrated that ip. administration of Korean red ginseng acidic polysaccharide (RGAP) exerts antitumor activity In mice. The present study was carried out to compare the effects of ip. and p.o. routes of administration of RGAP on either normal or tumor-bearing BALB/c mice. RGAP was administered either ip. or p.o. at doses of 100, 300, 500, 1000 mg/kg for 1 or 5 weeks. Peritoneal macrophages from mice treated with RGAP p.o. at a dose of 300 mg/kg either for 1 or 5 weeks did not exhibit growth inhibition activity toward WEHI-I64 tumor cells. However, administration of RGAP at a dose of 600 mg/kg for both 1 and 5 weeks increased the antitumor activity of macrophages. Oral administration of RGAP (600 mg/kg) for 5 weeks and ip. administration of RGAP (300 mg/kg) for 1 week resulted in antitumor activities of <TEX>$40\%$</TEX> and <TEX>$45\%$</TEX>, respectively, indicating that the effect of i.p. injection is more potent 2 and 5 times than that of p.o. one in terms of dose and duration, respectively. Tumor inhibition rates of RGAP at doses of 300, 500, 1000 mg/kg in mice transplanted with B16-F10 melanoma were 4.4, 12.0, and <TEX>$45.4\%$</TEX>, respectively, meaning that p.o. dose higher than 500 mg/kg possess marked antitumor activity. The results above suggests that p.o. administration of RGAP also show antitumor activity in vivo depending on the dose.

Enhancement of Antitumor Effects of Paclitaxel (Taxol) in Combination with Red Ginseng Acidic Polysaccharide (RGAP)

We have recently reported that red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng (Panax ginseng C.A. Meyer), shows immunomodulatory and antitumor activities, mainly mediated by the nitric oxide (NO) production of macrophages. This compound may be used in cancer therapy alone or in combination with other chemotherapeutic agents. The synergistic effect of RGAP and paclitaxel (taxol) was evaluated to develop new biological response modifiers in cancer therapy. The present study demonstrates a synergistic antitumor effect of RGAP and paclitaxel in mice transplanted with sarcoma 180 and B16 melanoma. Combined treatment with paclitaxel (5 or 15 mg/kg) and RGAP (25 mg/kg) resulted in a 28.6 or 42.8 % increase in the life span of ICR mice bearing sarcoma 180 tumor cells, while no obvious effect was seen on sole paclitaxel treatment. When a combination of paclitaxel (10 mg/kg) and RGAP (100 mg/kg) was administered to C57BL/6 mice implanted with B16 melanoma, the tumor weight per mouse also decreased by 76.3 %, suggesting that RGAP may be used as an adjuvant in medicinal applications of paclitaxel. The augmented antitumor effect of paclitaxel is supposed to be the result of the immunomodulating antitumor effect of RGAP. RGAP, having B cell specific mitogenic activity, induced the secretion of interleukin-6 (IL-6) in spleen cells in a concentration-dependent manner (5 to 500 microg/microL). RGAP also restored the proliferation of splenocytes and NK cell activity suppressed by paclitaxel. Flow cytometric analysis of splenocytes in mice treated with paclitaxel showed a significant increase of CD11b+ cells. Additionally, a synergistic effect of RGAP and paclitaxel was found to effect an increased tumoricidal activity of macrophages. The above results suggest that clinical trials of RGAP as an adjuvant in cancer chemotherapy of paclitaxel are highly feasible.

홍삼산성다당체 (RGAP)와 항암제의 병용투여에 의한 항암시너지 효과

Sarcoma 180 암세포를 이식한 마우스에서 면역조절 작용을 갖는 홍삼산성다당체 (RGAP)를 항암제 cyclophosphamide (CY)와 병용투여한 결과, RGAP (100 mg/kg)와 CY (3 mg/kg)의 병용투여는 고용량의 CY (10 mg/kg) 단독투여보다 강한 항암작용을 나타내었다. 또한 RGAP (100 mg/kg)과 CY (10 또는 20 mg/kg)과의 병용투여는 CY의 단독투여보다 LL/2 폐종양을 보다 강하게 억제하였다. RGAP (100 mg/kg) 와 5-fluorouracil (5-FU) (2.5 mg/kg)을 병용투여하였을 때도 sarcoma 180 암세포를 이식한 마우스에서 5-FU 단독투여군에 비해 현저한 항암시너지 효과를 나타내었다. LL2 폐 종양에 미치는 결과에서도 RGAP (100 mg/kg)와 5-FU (5 또는 10 mg/kg) 병용투여군은 항암제 단독투여군보다 강한 항종양 효과를 나타내었다. 이상의 결과로부터 RGAP는 항암제 CY 또는 5-FU와 병용투여시 sarcoma 180 및 LL/2 폐종양에 대해서 저용량 항암제의 사용으로 고용량의 항암제 사용에서와 유사한 항암효과를 나타낼 수 있어서 항암효과를 극대화 시킬뿐만아니라 항암제 사용에 의한 면역독성과 같은 부작용을 경감시킬 수 있는 항암치료 보조제로서의 사용가능성을 제시하였다. Synergistic anticancer activities of red ginseng acidic polysaccharide (RGAS) showing immunomodulatory activity were evaluated by combined treatment with anticancer agents such as Cyclophosphamide (CY) or 5-Fluorouracil (5-FU) in experimental tumor models. The combined treatment of RGAP (100 mg/kg) and CY (3 mg/kg) exhibited 71% of survival rate in lift span of sarcoma 180-bearing mice, while single treatment of RGAP (100 mg/kg) and CY (3 or 10 mg/kg) exhibited 43, 14 and 43% of survival rates, respectively. In addition, when RGAP (100 mg/kg) was administered in combination with 5-FU (2.5 mg/kg) to sarcoma 180 tumor-bearing mice, higher survival rate was found when compared with RGAP or 5-FU treatment alone. Moreover, tumor weights in LL/2 lung carcinoma-bearing mice treated combined with RGAP (100 mg/kg) and 5-FU (5 or 10 mg/kg) was obviously decreased when compared with 5-FU alone. These results suggest that clinical trials of RGAP as an adjuvant in cancer chemotheraphy can be higly feasible.