Antiviral Activities of Asarones and Rhizomes of Acorus gramineus on Murine Norovirus.

Noroviruses (NVs) are a major cause of foodborne diseases worldwide. The rhizomes of Acorus gramineus (AGR) have been used as a traditional medicinal plant and a food additive. In this study, AGR and its bioactive components-α-asarone and ß-asarone-showed significant antiviral activities against murine NV (MNV) with pre-treatment, with more than two log reductions in viral plaques. They also demonstrated strong inhibition on binding to A- and O-type saliva by the recombinant P domain derived from human NV (HuNV) GII.4. Both α- and ß-asarones also inhibited the binding of the P domain to the receptor at 0.125-1 mM in a concentration-dependent manner and induced a marked reduction in Tm, suggesting that they may reduce structural stability and block receptor binding by the P domain. In simulated digestive conditions, the AGR extract, α-asarone, or ß-asarone further showed a significant reduction of MNV plaques by 1.5-2.8 logs. The asarones show a potential for development as a scaffold for anti-NV agents.

The extract of Celtis choseniana Nakai alleviates testosterone-induced benign prostatic hyperplasia through inhibiting 5α reductase type 2 and the Akt/NF-κB/AR pathway.

Benign prostatic hyperplasia (BPH) is a chronic male disease characterized by the enlarged prostate. Celtis chosenianaNakai (C. choseniana) is medicinally used to alleviate pain, gastric disease, and lung abscess. In this study, the effect of C. choseniana extract on BPH was investigated using testosterone-induced rats. Sprague Dawley rats were divided into five groups: control, BPH (testosterone 5 mg·kg-1), Fina (finasteride 2 mg·kg-1), and C. choseniana (50 and 100 mg·kg-1). After four weeks of TP treatment with finasteride or C. choseniana, prostate weights and DHT levels were measured. In addition, the prostates were histopathologically examined and measured for protein kinase B (Akt)/nuclear factor-κB (NF-κB)/AR signaling, proliferation, apoptosis, and autophagy. Prostate weight and epithelial thickness were reduced in the C. choseniana groups compared with that in the BPH group. The extract of C. choseniana acted as a 5α reductase inhibitor, reducing DHT levels in the prostate. Furthermore, the extract of C. choseniana blocked the activation of p-Akt, nuclear NF-κB activation and reduced the expression of AR and PSA compared with BPH. Moreover, the expression of Bax, PARP-1, and p53 increased, while the expression of bcl-2 decreased. The present study demonstrated that C. choseniana extract alleviated testosterone-induced BPH by suppressing 5α reductase and Akt/NF-κB activation, reducing AR signaling and inducing apoptosis and autophagy in the prostate. These results suggested that C. choseniana probably contain potential herbal agents to alleviate BPH.

Stauntonia hexaphylla Extract Ameliorates Androgenic Alopecia by Inhibiting Androgen Signaling in Testosterone-induced Alopecia Mice.

Background: Stauntonia hexaphylla has been a traditional folk remedy for alleviating fever and providing anti-inflammatory properties. Androgenetic alopecia (AGA) is the most common form mediated by the presence of the dihydrotestosterone (DHT). Objectives: In this study, we evaluated the effects of an extract of S. hexaphylla on AGA models and its mechanisms of action. Methods: We studied S. hexaphylla extract to evaluate 5α-reductase and androgen receptor (AR) levels, apoptosis, and cell proliferation in vitro and in vivo. In addition, paracrine factors for androgenic alopecia, such as transforming growth factor beta-1 (TGF-ß1) and dickkopf-a (DKK-1), were examined. Apoptosis was investigated, and the evaluation of proliferation was examined with cytokeratin 14 (CK-14) and proliferating cell nuclear antigen (PCNA). Results: In human follicular dermal papilla cells, the 5α-reductase and AR were decreased following S. hexaphylla treatment, which reduced the Bax/Bcl-2 ratio. Histologically, the dermal thickness and follicle number were higher in the S. hexaphylla groups compared with the AGA group. In addition, the DHT concentration, 5α-reductase, and AR were decreased, thereby downregulating TGF-ß1 and DKK-1 expression and upregulating cyclin D in S. hexaphylla groups. The numbers of keratinocyte-positive and PCNA-positive cells were increased compared to those in the AGA group. Conclusions: The present study demonstrated that the S. hexaphylla extract ameliorated AGA by inhibiting 5α-reductase and androgen signaling, reducing AGA paracrine factors that induce keratinocyte (KC) proliferation, and inhibition apoptosis and catagen prematuration.

Lenvatinib is independently associated with the reduced risk of progressive disease when compared with sorafenib in patients with advanced hepatocellular carcinoma.

BACKGROUND AND AIMS: Recently, lenvatinib demonstrated non-inferiority to sorafenib in terms of overall survival (OS) in a randomized phase III study that was conducted at 154 sites in 20 countries. Here, we investigated treatment outcomes and safety of lenvatinib compared with sorafenib and identified independent predictors of poor outcomes, including shorter progression-free survival (PFS) and OS in Korean patients with unresectable hepatocellular carcinoma (HCC). METHODS: Patients with advanced HCC treated with lenvatinib or sorafenib at Yonsei Liver Center, Severance Hospital, Yonsei University College of Medicine between October 2018 to October 2019 were considered eligible. Response evaluation was performed according to the modified Response Evaluation Criteria in Solid Tumors. RESULTS: The lenvatinib arm had a significantly lower proportion of patients who received prior anti-HCC treatments (47.7% vs 78.7%; P < 0.001) than those in the sorafenib arm. Univariate analysis showed that ECOG 1 (vs 0), serum albumin, alpha-fetoprotein (AFP), previous anti-HCC treatments, and lenvatinib (vs sorafenib) were significant predictors of progressive disease (all P < 0.05). In the subsequent multivariate analysis, ECOG 1 (vs 0) (hazard ratio [HR] = 4.721, 95% confidence interval [CI] 1.371-16.259; P = 0.014), higher AFP level (HR = 1.000, 95% CI 1.000-1.000; P = 0.015), and lenvatinib treatment (vs sorafenib) (HR = 0.461, 95% CI 0.264-0.804; P = 0.006) independently predicted a higher probability of progressive disease. CONCLUSIONS: Patients treated with lenvatinib demonstrated significantly longer PFS than those treated with sorafenib. Furthermore, no significant differences were observed in mortality rates between the two groups, which indicated that lenvatinib is non-inferior to sorafenib in terms of OS.

Inhibitory Effects of Laminaria japonica Fucoidans Against Noroviruses.

Norovirus is the leading cause of nonbacterial foodborne disease outbreaks. Human noroviruses (HuNoVs) bind to histo-blood group antigens as the host receptor for infection. In this study, the inhibitory effects of fucoidans from brown algae, Laminaria japonica (LJ), Undaria pinnatifida and Undaria pinnatifida sporophyll, were evaluated against murine norovirus (MNoV), feline calicivirus (FCV) and HuNoV. Pretreatment of MNoV or FCV with the fucoidans at 1 mg/mL showed high antiviral activities, with 1.1 average log reductions of viral titers in plaque assays. They also showed significant inhibition on the binding of the P domains of HuNoV GII.4 and GII.17 to A- or O-type saliva and the LJ fucoidan was the most effective, reaching 54-72% inhibition at 1 mg/mL. In STAT1-/- mice infected with MNoV, oral administration of the LJ fucoidan, composed of mainly sulfated fucose and minor amounts of glucose and galactose, improved the survival rates of mice and significantly reduced the viral titers in their feces. Overall, these results provide the LJ fucoidan can be used to reduce NoV outbreaks.

Protective effects of combination of Stauntonia hexaphylla and Cornus officinalis on testosterone-induced benign prostatic hyperplasia through inhibition of 5α- reductase type 2 and induced cell apoptosis.

Benign prostatic hyperplasia (BPH) is a progressive pathological condition associated with proliferation of prostatic tissues, prostate enlargement, and lower-urinary tract symptoms. However, the mechanism underlying the pathogenesis of BPH is unclear. The aim of this study was to investigate the protective effects of a combination of Stauntonia hexaphylla and Cornus officinalis (SC extract) on a testosterone propionate (TP)-induced BPH model. The effect of SC extract was examined in a TP-induced human prostate adenocarcinoma cell line. Male Sprague-Dawley rats were randomly divided into 5 groups (n = 6) for in vivo experiments. To induce BPH, all rats, except those in the control group, were administered daily with subcutaneous injections of TP (5 mg/kg) and orally treated with appropriate phosphate buffered saline/drugs (finasteride/saw palmetto/SC extract) for 4 consecutive weeks. SC extract significantly downregulated the androgen receptor (AR), prostate specific antigen (PSA), and 5α-reductase type 2 in TP-induced BPH in vitro. In in vivo experiments, SC extract significantly reduced prostate weight, size, serum testosterone, and dihydrotestosterone (DHT) levels. Histologically, SC extract markedly recovered TP-induced abnormalities and reduced prostatic hyperplasia, thereby improving the histo-architecture of TP-induced BPH rats. SC extract also significantly downregulated AR and PSA expression, as assayed using immunoblotting. Immunostaining revealed that SC extract markedly reduced the 5α-reductase type 2 and significantly downregulated the expression of proliferating cell nuclear antigen. In addition, immunoblotting of B-cell lymphoma 2 (Bcl-2) family proteins indicated that SC extract significantly downregulated anti-apoptotic Bcl-2 and markedly upregulated pro-apoptotic B cell lymphoma-associated X (Bax) expression. Furthermore, SC treatment significantly decreased the Bcl-2/Bax ratio, indicating induced prostate cell apoptosis in TP-induced BPH rats. Thus, our findings demonstrated that SC extract protects against BPH by inhibiting 5α-reductase type 2 and inducing prostate cell apoptosis. Therefore, SC extract might be useful in the clinical treatment of BPH.

Antiviral effects of black raspberry (Rubus coreanus) seed extract and its polyphenolic compounds on norovirus surrogates.

Black raspberry seeds, a byproduct of wine and juice production, contain large quantities of polyphenolic compounds. The antiviral effects of black raspberry seed extract (RCS) and its fraction with molecular weight less than 1 kDa (RCS-F1) were examined against food-borne viral surrogates, murine norovirus-1 (MNV-1) and feline calicivirus-F9 (FCV-F9). The maximal antiviral effect was achieved when RCS or RCS-F1 was added simultaneously to cells with MNV-1 or FCV-F9, reaching complete inhibition at 0.1-1 mg/mL. Transmission electron microscopy (TEM) images showed enlarged viral capsids or disruption (from 35 nm to up to 100 nm) by RCS-F1. Our results thus suggest that RCS-F1 can interfere with the attachment of viral surface protein to host cells. Further, two polyphenolic compounds derived from RCS-F1, cyanidin-3-glucoside (C3G) and gallic acid, identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against the viruses. C3G was suggested to bind to MNV-1 RNA polymerase and to enlarge viral capsids using differential scanning fluorimetry and TEM, respectively.

Anti-fibrotic effect of natural toxin bee venom on animal model of unilateral ureteral obstruction.

Progressive renal fibrosis is the final common pathway for all kidney diseases leading to chronic renal failure. Bee venom (BV) has been widely used as a traditional medicine for various diseases. However, the precise mechanism of BV in ameliorating the renal fibrosis is not fully understood. To investigate the therapeutic effects of BV against unilateral ureteral obstruction (UUO)-induced renal fibrosis, BV was given intraperitoneally after ureteral ligation. At seven days after UUO surgery, the kidney tissues were collected for protein analysis and histologic examination. Histological observation revealed that UUO induced a considerable increase in the number of infiltrated inflammatory cells. However, BV treatment markedly reduced these reactions compared with untreated UUO mice. The expression levels of TNF-α and IL-1ß were significantly reduced in BV treated mice compared with UUO mice. In addition, treatment with BV significantly inhibited TGF-ß1 and fibronectin expression in UUO mice. Moreover, the expression of α-SMA was markedly withdrawn after treatment with BV. These findings suggest that BV attenuates renal fibrosis and reduces inflammatory responses by suppression of multiple growth factor-mediated pro-fibrotic genes. In conclusion, BV may be a useful therapeutic agent for the prevention of fibrosis that characterizes progression of chronic kidney disease.

Inhibitory effects of bee venom on Propionibacterium acnes-induced inflammatory skin disease in an animal model.

Propionibacterium acnes (P. acnes) is a major contributing factor to the inflammatory component of acne. The many prescription medications for acne allow for a large number of potential combination treatments. However, several antibiotics, apart from their antibacterial effects, exert side­effects, such as the suppression of host inflammatory responses. Purified bee venom (BV) is a natural toxin produced by honeybees (Apis mellifera L.). BV has been widely used as a traditional medicine for various diseases. In the present study, to investigate the therapeutic effects of BV against P. acnes-induced inflammatory skin disease, P. acnes was intradermally injected into the ears of mice. After the injection, BV was applied to the skin surface of the right ear. Histological observation revealed that P. acnes induced a considerable increase in the number of infiltrated inflammatory cells. However, treatment with BV markedly reduced these reactions compared with the P. acnes-injected mice not treated with BV. Moreover, the expression levels of tumor necrosis factor (TNF)-α, and interleukin (IL)-1ß were significantly reduced in the BV-treated mice compared with the untreated P. acnes-injected mice. In addition, treatment with BV significantly inhibited Toll-like receptor (TLR)2 and CD14 expression in P. acnes-injected tissue. The binding activity of nuclear factor-κB (NF-κB) and activator protein (AP)-1 was markedly suppressed following treatment with BV. The results from our study, using an animal model, indicate that BV exerts an inhibitory effect on inflammatory skin diseases. In conclusion, our data indicate that BV has potential for use as an anti-acne agent and may be useful in the pharmaceutical and cosmetics industries.

Antiviral effects of black raspberry (Rubus coreanus) juice on foodborne viral surrogates.

Abstract Human noroviruses (HuNoVs) are the most frequent cause of foodborne viral gastroenteritis, causing approximately 90% of non-bacterial epidemic outbreaks around the world. Rubus coreanus is a species of black raspberry, rich in polyphenols, and known to exert anti-inflammatory, antibacterial, and antiviral activities. In the present study, the antiviral effects of R. coreanus juice (black raspberry [BRB] juice) on foodborne viral surrogates, murine norovirus-1 (MNV-1) and feline calicivirus-F9 (FCV-F9), were compared with those of cranberry juice, grape juice, and orange juice by plaque assays. Among the four juices tested, BRB juice was the most effective in reducing plaques formation of these viruses. Time-of-addition experiments were designed to determine the mechanism of action of BRB juice on MNV-1 and FCV-F9. The maximal antiviral effect of BRB juice against MNV-1 was observed when it was added to RAW 264.7 cells (mouse leukemic monocyte macrophage cell line) simultaneously with the virus. Pre-treatment of either Crandell Reese Feline Kidney cells or FCV-F9 with BRB juice exhibited significant antiviral activity. The inhibition of viral infection by BRB juice on MNV-1 and FCV-F9 probably occurs at the internalization of virions into the cell or the attachment of the viral surface protein to the cellular receptor. The polyphenol components in BRB (i.e., gallic acid and quercetin), however, did not show any activity against these viruses. Our data provide great promise for the utilization of BRB in the prevention of foodborne viral outbreaks.

The Protective Effect of Apamin on LPS/Fat-Induced Atherosclerotic Mice.

Apamin, a peptide component of bee venom (BV), has anti-inflammatory properties. However, the molecular mechanisms by which apamin prevents atherosclerosis are not fully understood. We examined the effect of apamin on atherosclerotic mice. Atherosclerotic mice received intraperitoneal (ip) injections of lipopolysaccharide (LPS, 2 mg/kg) to induce atherosclerotic change and were fed an atherogenic diet for 12 weeks. Apamin (0.05 mg/kg) was administered by ip injection. LPS-induced THP-1-derived macrophage inflammation treated with apamin reduced expression of tumor necrosis factor (TNF)-α, vascular cell adhesion molecule (VCAM)-1, and intracellular cell adhesion molecule (ICAM)-1, as well as the nuclear factor kappa B (NF-κB) signaling pathway. Apamin decreased the formation of atherosclerotic lesions as assessed by hematoxylin and elastic staining. Treatment with apamin reduced lipids, Ca(2+) levels, and TNF-α in the serum from atherosclerotic mice. Further, apamin significantly attenuated expression of VCAM-1, ICAM-1, TGF-ß1, and fibronectin in the descending aorta from atherosclerotic mice. These results indicate that apamin plays an important role in monocyte/macrophage inflammatory processing and may be of potential value for preventing atherosclerosis.

Bee venom reduces atherosclerotic lesion formation via anti-inflammatory mechanism.

The components of bee venom (BV) utilized in the current study were carefully scrutinized with chromatography. Despite its well documented anti-inflammatory property, there are no reports regarding the influence of BV on the expression of cellular adhesion molecules in the vascular endothelium. A great amount of information exists concerning the effects of an atherogenic diet on atherosclerotic changes in the aorta, but little is known about the molecular mechanisms and the levels of gene regulation involved in the anti-inflammatory process induced by BV. The experimental atherosclerosis was induced in mice by a lipopolysaccharide (LPS) injection and an atherogenic diet. The animals were divided into three groups, the NC groups of animals that were fed with a normal diet, the LPS/fat group was fed with the atherogenic diet and received intraperitoneal injections of LPS, and the LPS/fat + BV group was given LPS, an atherogenic diet and intraperitoneal BV injections. At the end of each treatment period, the LPS/fat + BV group had decreased levels of total cholesterol (TC) and triglyceride (TG) in their serum, compared to the LPS/fat group. The LPS/fat group had significant expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1ß in the serum, compared with the NC group (p < 0.05). The amount of cytokines reduced consistently in the BV treatment groups compared with those in LPS/fat group. BV significantly reduced the amount of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), transforming growth factor-ß1 (TGF-ß1) and fibronectin in the aorta, compared with the LPS/fat group (p < 0.05). A similar pattern was also observed in the heart. In conclusion, BV has anti-atherogenic properties via its lipid-lowering and anti-inflammatory mechanisms.

Bee venom inhibits hepatic fibrosis through suppression of pro-fibrogenic cytokine expression.

Bee venom (BV) has a long tradition of use for the control of pain and inflammation in various chronic diseases. Carbon tetrachloride (CCl4) is known to induce hepatotoxicity after being metabolized to the highly reactive trichloromethyl free radical and its peroxy radical. The purpose of the current study was to examine whether BV regulates the pro-inflammation and fibrosis related genes against a mouse model of hepatic fibrosis induced by CCl4 and ethanol-treated hepatocytes (ETH). Test mice were administered with CCl4 (2 ml/mg) and hepatocytes were treated with 25 mM ethanol. BV was added to the final concentration of 0.05-0.5 mg/kg and 1-100 ng/ml for in vivo and in vitro testing, respectively. Fibrotic livers and ETH were used for the measurement of hepatocyte necrosis, pro-inflammatory cytokines and fibrogenic genes. BV suppressed CCl4-induced hepatocyte necrosis markers of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). It also inhibited the secretion of interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha. Moreover, BV inhibited CCl4-induced expression of transforming growth factor (TGF)-beta1, alpha-smooth muscle actin (SMA) and fibronectin. Similarly, ETH exhibited significant suppression of IL-1beta, TNF-alpha, TGF-beta1 and fibronectin when cultured with BV. These results suggest that BV possesses anti-fibrogenic properties that are mediated by the suppression of pro-inflammatory cytokines and fibrogenic gene expression. BV has substantial therapeutic potential for the treatment of fibrotic diseases.

Bee venom protects hepatocytes from tumor necrosis factor-alpha and actinomycin D.

Honeybee (Apis mellifera) venom (BV) has a broad array of therapeutic applications in traditional medicine to treat variety of diseases. It is also known that BV possesses anti-inflammatory and anticancer effect and that it can inhibit proliferation and induces apoptosis in cancer cells, but there is no evidence of information regarding anti-apoptosis of BV on hepatocytes. In the present study, we investigated the anti-apoptotic effect of BV on tumor necrosis factor (TNF)-alpha with actinomycin (Act) D induces apoptosis in hepatocytes. TNF-alpha/Act D-treated hepatocytes were exposed to different low concentration (1, 10 and 100 ng/mL) of BV. Our results showed statistically significant inhibition in DNA damage caused by BV treatment compared to corresponding TNF-alpha/Act D-treated hepatocytes. BV suppressed TNF-alpha/Act Dtreated activation of bcl-2 family and caspase family, which resulted in inhibition of cytochrome c release and PARP cleavage. These results demonstrate that low concentration BV possess a potent suppressive effect on anti-apoptotic responses of TNF-alpha/Act D-treated hepatocytes and suggest that these compounds may contribute substantial therapeutic potential for the treatment of liver diseases.

Inhibition of pathogen adhesion to host cells by polysaccharides from Panax ginseng.

PG-F2 and PG-HMW from Panax ginseng are pectin-type polysaccharides and PG-HMW might be an arabinogalactan. They demonstrated strong anti-adhesive activities against oral and skin pathogens to host cell lines in a dose-dependent manner from 0.1 to 2.0 mg/ml. While enzymatic hydrolysis caused complete loss of anti-adhesive activities, partial hydrolysis produced oligosaccharides with anti-adhesive properties. PG-F2 and PG-HMW might have a selective anti-adhesive effect against certain pathogenic bacteria without adverse effects on commensal bacteria.

In vitro anti-adhesive activity of green tea extract against pathogen adhesion.

Camellia sinensis polysaccharide has been reported to possess anti-adhesive activity against pathogens. The present study was designed to investigate whether hot water extracts obtained from green tea leaves might inhibit pathogen adhesion to human or mouse cell lines. Green tea extract-4 (CSI-4) with the maximum yield of 4% (w/v) is composed of a major proportion of carbohydrates containing 40% uronic acids, but lack of catechins. It showed strong inhibitory activities against hemagglutination mediated by pathogens Helicobacter pylori, Propionibacterium acnes and Staphylococcus aureus with the minimum inhibitory concentrations of 0.01-0.5 mg/mL. CSI-4 further demonstrated an inhibitory effect on the adhesion of these pathogens to host cell lines with the IC(50) values (50% inhibition of adhesion) of 0.14-2.3 mg/mL. It exhibited the highest activity against P. acnes, but no inhibitory effects were observed against Lactobacillus acidophilus, Bifidobacterium bifidum, Escherichia coli, or Staphylococcus epidermidis. Our results suggest that CSI-4 may exert a selective anti-adhesive effect against certain pathogenic bacteria with no adverse effects against beneficial or commensal bacteria.

Inhibition of pathogenic bacterial adhesion by acidic polysaccharide from green tea (Camellia sinensis).

An acidic polysaccharide CS-F2 from Camellia sinensis was examined to characterize its anti-adhesive effects against pathogenic bacteria, most notably Helicobacter pylori, Propionibacterium acnes, and Staphylococcus aureus. CS-F2 showed marked inhibitory activity against the pathogen-mediated hemagglutination with a minimum inhibitory concentration (MIC) between 0.01 and 0.1 mg/mL, which is lower than the previously reported MIC values for Panax ginseng and Artemisia capillaris. The inhibitory effects of CS-F2 on the adhesion of H. pylori to AGS adenocarcinoma gastric epithelial cells, or P. acnes and S. aureus to NIH 3T3 fibroblast cells, were further assessed resulting in MIC values between 0.063 and 0.13 mg/mL. Importantly, CS-F2 showed no inhibitory effects against Lactobacillus acidophilus, Escherichia coli, or Staphylococcus epidermidis. Our results suggest that CS-F2, which is a pectin-type polysaccharide with a molecular weight of approximately 8.0 x 10(4) Da, may exert a selective anti-adhesive effect against certain pathogenic bacteria, while exerting no effects against beneficial and commensal bacteria.

Pectin-like acidic polysaccharide from Panax ginseng with selective antiadhesive activity against pathogenic bacteria.

Previous studies have revealed the inhibitory effects of an acidic polysaccharide purified from the root of Panax ginseng against the adhesion of Helicobacter pylori to gastric epithelial cells and the ability of Porphyromonas gingivalis to agglutinate erythrocytes. In this study, this acidic polysaccharide from P. ginseng, PG-F2, was investigated further, in order to characterize its antiadhesive effects against Actinobacillus actinomycetemcomitans, Propionibacterium acnes, and Staphylococcus aureus. The minimum inhibitory concentrations (MIC) were found to be in a range of 0.25-0.5mg/mL. However, results showed no inhibitory effects of PG-F2 against Lactobacillus acidophilus, Escherichia coli, or Staphylococcus epidermidis. PG-F2 is a pectin-type polysaccharide with a mean MW of 1.2 x 10(4) Da, and consists primarily of galacturonic and glucuronic acids along with rhamnose, arabinose, and galactose as minor components. The complete hydrolysis of PG-F2 via chemical or carbohydrolase enzyme treatment resulted in the abrogation of its antiadhesive activity, but limited hydrolysis via treatment with pectinase (EC. 3.2.1.15) yielded an oligosaccharide fraction, with activity comparable to the precursor PG-F2 (the MIC of ca. 0.01 mg/mL against H. pylori and P. gingivalis). Our results suggest that PG-F2 may exert a selective antiadhesive effect against pathogenic bacteria, while having no effects on beneficial and commensal bacteria.

Inhibition of Helicobacter pylori adhesion to human gastric adenocarcinoma epithelial cells by acidic polysaccharides from Artemisia capillaris and Panax ginseng.

Helicobacter pylori specifically adheres to host cells, mainly based on carbohydrate-mediated cell-cell interactions. Previously, we investigated the anti-adhesive effect of polysaccharide fractions from Artemisia capillaris and Panax ginseng, using hemagglutination and enzyme-linked glycosorbent assays. In the present study, each active polysaccharide fraction was further purified, resulting in a single peak (fraction F2) using gel filtration FPLC, in which no protein content was detectable. Using scanning electron microscopy, we examined the inhibitory effects of these polysaccharides on the attachment of H. pylori to the human gastric adenocarcinoma epithelial cell line. The bacterial attachment to the cell line was inhibited by these polysaccharides in the range of the concentrations studied (0.2 - 2.8 mg/mL), showing their minimum inhibitory concentration at as low as 0.2 mg/mL. The bacterial binding was inhibited more effectively by P. ginseng polysaccharides, than by those from A. capillaris. The purified polysaccharides contain similar sugar compositions and have high amounts of uronic acids. Our results suggest that acidic carbohydrates may play an important role in the inhibitory activity on H. pylori adhesion to host cells and that our established purification protocol can be applied to obtain active acidic polysaccharides from plant sources.

In vitro anti-adhesive activity of an acidic polysaccharide from Panax ginseng on Porphyromonas gingivalis binding to erythrocytes.

A polysaccharide with high uronic acid content from the roots of Panax ginseng was found to inhibit the ability of Porphyromonas gingivalis to agglutinate erythrocytes. This polysaccharide showed a strong inhibitory activity (minimum inhibitory concentration 0.25 mg/mL), but treatment with pectinase resulted in non-inhibitory hydrolyzed products. In contrast, the inhibition by the acidic polysaccharide from the leaves of Artemisia capillaris was negligible. The carbohydrate composition of the two polysaccharides indicated that the anti-adhesive activity may be correlated with glucuronic acid content, one of the components of glycosaminoglycans. Low molecular weight heparin and sucrose octasulfate revealed stronger inhibitory effects on bacterial binding, than the acidic polysaccharide from P. ginseng.