Ginsenoside Rd attenuates the inflammatory response via modulating p38 and JNK signaling pathways in rats with TNBS-induced relapsing colitis

Ginsenosides from Panax ginseng as potential therapeutic candidates for the treatment of inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is characterized by a chronic inflammation of the intestine, which significantly affects patients' quality of life. As a perennial plant with the homology of medicine and food, Panax ginseng is known for its substantial anti-inflammatory effects in various inflammatory disorders. Ginsenosides, the main bioactive compounds of P. ginseng, are recognized for their efficacy in ameliorating inflammation.

PURPOSE

Over the past decade, approximately 150 studies have investigated the effects of P. ginseng and ginsenosides on IBD treatment and new issues have arisen. However, there has yet to be a comprehensive review assessing the potential roles of ginsenosides in IBD therapy.

METHOD

This manuscript strictly adheres to the PRISMA guidelines, thereby guaranteeing systematic synthesis of data. The research articles referenced were sourced from major scientific databases, including Google Scholar, PubMed, and Web of Science. The search strategy employed keywords such as "ginsenoside", "IBD", "colitis", "UC", "inflammation", "gut microbiota", and "intestinal barrier". For image creation, Figdraw 2.0 was methodically employed.

RESULTS

Treatment with various ginsenosides markedly alleviated clinical IBD symptoms. These compounds have been observed to restore intestinal epithelia, modulate cellular immunity, regulate gut microbiota, and suppress inflammatory signaling pathways.

CONCLUSION

An increasing body of research supports the potential of ginsenosides in treating IBD. Ginsenosides have emerged as promising therapeutic agents for IBD, attributed to their remarkable efficacy, safety, and absence of side effects. Nevertheless, their limited bioavailability presents a substantial challenge. Thus, efforts to enhance the bioavailability of ginsenosides represent a crucial and promising direction for future IBD research.

Pharmacological effects of ginseng and ginsenosides on intestinal inflammation and the immune system

Intestinal inflammatory imbalance and immune dysfunction may lead to a spectrum of intestinal diseases, such as inflammatory bowel disease (IBD) and gastrointestinal tumors. As the king of herbs, ginseng has exerted a wide range of pharmacological effects in various diseases. Especially, it has been shown that ginseng and ginsenosides have strong immunomodulatory and anti-inflammatory abilities in intestinal system. In this review, we summarized how ginseng and various extracts influence intestinal inflammation and immune function, including regulating the immune balance, modulating the expression of inflammatory mediators and cytokines, promoting intestinal mucosal wound healing, preventing colitis-associated colorectal cancer, recovering gut microbiota and metabolism imbalance, alleviating antibiotic-induced diarrhea, and relieving the symptoms of irritable bowel syndrome. In addition, the specific experimental methods and key control mechanisms are also briefly described.

Ginseng Berry Juice (GBJ) Regulates the Inflammation in Acute Ulcerative Mouse Models and the Major Bioactive Substances Are Ginsenosides Rb3, Rc, Rd, and Re

Panax ginseng fruit is known to have various biological effects owing to its large amount of saponins such as ginsenosides. In the present study, ginseng berry juice was confirmed to be effective against acute inflammation. Ginseng berry juice was used for analysis of active constituents, antioxidant efficacy, and in vivo inflammation. A high-performance liquid chromatography method was used for analysis of ginsenosides. In an HCl/ethanol-induced acute gastric injury model, microscopic, immunofluorescent, and immunohistochemical techniques were used for analysis of inhibition of gastric injury and mechanism study. In a mouse model of acute gastritis induced with HCl/ethanol, ginseng berry juice (GBJ, 250 mg/kg) showed similar gastric injury inhibitory effects as cabbage water extract (CB, 500 mg/kg, P.O). GBJ dose-dependently modulated the pro-inflammatory cytokines such as Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), and Interleukin-13 (IL-13). GBJ inhibited the activation of Nuclear Factor kappa bB (NF-κB) and suppressed the expressions of cyclooxigenase-2 (COX-2) and prostaglandin 2 (PGE2). The anti-inflammatory effect of GBJ is attributed to ginsenosides which have anti-inflammatory effects. Productivity as an effective food source for acute gastritis was analyzed and showed that GBJ was superior to CB. In addition, as a functional food for suppressing acute ulcerative symptoms, it was thought that the efficacy of gastric protection products would be higher if GBJ were produced in the form of juice rather than through various extraction methods.

Terpenes: Modulating anti-inflammatory signaling in inflammatory bowel disease

Inflammatory Bowel Disease (IBD) are autoimmune diseases characterized by chronic intestinal inflammation. Considered a western disease, IBD incidence in newly developed countries is skyrocketing. Accordingly, global prevalence is steadily increasing. There are two major IBD phenotypes, ulcerative colitis (UC) and Crohn's disease (CD). UC manifests as uninterrupted inflammation localized in the colon and rectum. Meanwhile, CD presents as interrupted inflammation that can occur throughout the digestive tract. As a result, therapeutics have focused on anti-inflammatory approaches for its treatment. Unfortunately, only 50% of patients benefit from current Food and Drug Administration approved treatments, and all are associated with serious adverse effects. Thus, there is a need for safer and novel therapeutics to increase the efficacy in this population. One aspect that is critical in understanding IBD is how food and phytochemicals therein may be associated with modifying the pathogenesis of IBD. A variety of retrospective and prospective studies, and clinical trials have shown benefits of plant-rich diets on the prevention and symptomatic improvement of IBD. The Mediterranean diet is rich in vegetables, fruits, legumes, and herbs; and characterized by the abundance of anti-inflammatory phytochemicals. An understudied phytochemical class enriched in this diet is terpenes; isoprene-based molecules are widely available in Mediterranean herbs and citrus fruits. Various terpenes have been evaluated in different IBD models. However, some present contradictory or inconclusive results. Therefore, in this review we evaluated preclinical studies of terpenes modulating basic inflammatory signaling related to IBD.

p38 MAPK-dependent phosphorylation of TFEB promotes monocyte-to-macrophage differentiation

The transcription factor EB (TFEB) regulates energy homeostasis and cellular response to a wide variety of stress conditions, including nutrient deprivation, oxidative stress, organelle damage, and pathogens. Here we identify S401 as a novel phosphorylation site within the TFEB proline-rich domain. Phosphorylation of S401 increases significantly in response to oxidative stress, UVC light, growth factors, and LPS, whereas this increase is prevented by p38 MAPK inhibition or depletion, revealing a new role for p38 MAPK in TFEB regulation. Mutation of S401 in THP1 cells demonstrates that the p38 MAPK/TFEB pathway plays a particularly relevant role during monocyte differentiation into macrophages. TFEB-S401A monocytes fail to upregulate the expression of multiple immune genes in response to PMA-induced differentiation, including critical cytokines, chemokines, and growth factors. Polarization of M0 macrophages into M1 inflammatory macrophages is also aberrant in TFEB-S401A cells. These results indicate that TFEB-S401 phosphorylation links differentiation signals to the transcriptional control of monocyte differentiation.

Biotransformation, Pharmacokinetics, and Pharmacological Activities of Ginsenoside Rd Against Multiple Diseases

Panax ginseng C.A. Mey. has a history of more than 4000 years and is widely used in Asian countries. Modern pharmacological studies have proved that ginsenosides and their compounds have a variety of significant biological activities on specific diseases, including neurodegenerative diseases, certain types of cancer, gastrointestinal disease, and metabolic diseases, in which most of the interest has focused on ginsenoside Rd. The evidentiary basis showed that ginsenoside Rd ameliorates ischemic stroke, nerve injury, cancer, and other diseases involved in apoptosis, inflammation, oxidative stress, mitochondrial damage, and autophagy. In this review, we summarized available reports on the molecular biological mechanisms of ginsenoside Rd in neurological diseases, cancer, metabolic diseases, and other diseases. We also discussed the main biotransformation pathways of ginsenoside Rd obtained by fermentation.

Danshensu alleviates pseudo-typed SARS-CoV-2 induced mouse acute lung inflammation

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can induce acute inflammatory response like acute lung inflammation (ALI) or acute respiratory distress syndrome, leading to severe progression and mortality. Therapeutics for treatment of SARS-CoV-2-triggered respiratory inflammation are urgent to be discovered. Our previous study shows that Salvianolic acid C potently inhibits SARS-CoV-2 infection. In this study, we investigated the antiviral effects of a Salvia miltiorrhiza compound, Danshensu, in vitro and in vivo, including the mechanism of S protein-mediated virus attachment and entry into target cells. In authentic and pseudo-typed virus assays in vitro, Danshensu displayed a potent antiviral activity against SARS-CoV-2 with EC₅₀ of 0.97 μM, and potently inhibited the entry of SARS-CoV-2 S protein-pseudo-typed virus (SARS-CoV-2 S) into ACE2-overexpressed HEK-293T cells (IC₅₀ = 0.31 μM) and Vero-E6 cell (IC₅₀ = 4.97 μM). Mice received SARS-CoV-2 S via trachea to induce ALI, while the VSV-G treated mice served as controls. The mice were administered Danshensu (25, 50, 100 mg/kg, i.v., once) or Danshensu (25, 50, 100 mg·kg^-1·d^-1, oral administration, for 7 days) before SARS-CoV-2 S infection. We showed that SARS-CoV-2 S infection induced severe inflammatory cell infiltration, severely damaged lung tissue structure, highly expressed levels of inflammatory cytokines, and activated TLR4 and hyperphosphorylation of the NF-κB p65; the high expression of angiotensinogen (AGT) and low expression of ACE2 at the mRNA level in the lung tissue were also observed. Both oral and intravenous pretreatment with Danshensu dose-dependently alleviated the pathological alterations in mice infected with SARS-CoV-2 S. This study not only establishes a mouse model of pseudo-typed SARS-CoV-2 (SARS-CoV-2 S) induced ALI, but also demonstrates that Danshensu is a potential treatment for COVID-19 patients to inhibit the lung inflammatory response.

Insights into Recent Studies on Biotransformation and Pharmacological Activities of Ginsenoside Rd

It is well known that ginsenosides—major bioactive constituents of Panax ginseng—are attracting more attention due to their beneficial pharmacological activities. Ginsenoside Rd, belonging to protopanaxadiol (PPD)-type ginsenosides, exhibits diverse and powerful pharmacological activities. In recent decades, nearly 300 studies on the pharmacological activities of Rd—as a potential treatment for a variety of diseases—have been published. However, no specific, comprehensive reviews have been documented to date. The present review not only summarizes the in vitro and in vivo studies on the health benefits of Rd, including anti-cancer, anti-diabetic, anti-inflammatory, neuroprotective, cardioprotective, ischemic stroke, immunoregulation, and other pharmacological effects, it also delves into the inclusion of potential molecular mechanisms, providing an overview of future prospects for the use of Rd in the treatment of chronic metabolic diseases and neurodegenerative disorders. Although biotransformation, pharmacokinetics, and clinical studies of Rd have also been reviewed, clinical trial data of Rd are limited; the only data available are for its treatment of acute ischemic stroke. Therefore, clinical evidence of Rd should be considered in future studies.

Ginsenoside Rd: A promising natural neuroprotective agent

BACKGROUND

Neurological diseases seriously affect human health, which are arousing wider attention, and it is a great challenge to discover neuroprotective drugs with minimal side-effects and better efficacies. Natural agents derived from herbs or plants have become unparalleled resources for the discovery of novel drug candidates. Panax ginseng C. A. Meyer, a well-known herbal medicine in China, occupies a very important position in traditional Chinese medicines (TCMs) with a long history of clinical application. Ginsenoside Rd is the active compound in P. ginseng known to have broad-spectrum pharmacological effects to reduce neurological damage that can lead to neurological diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, depression, cognitive impairment, and cerebral ischemia.

PURPOSE

To review and discuss the effects and mechanisms of ginsenoside Rd in the treatment of neurological diseases.

STUDY DESIGN & METHODS

The related information was compiled by the major scientific databases, such as Chinese National Knowledge Infrastructure (CNKI), Elsevier, ScienceDirect, PubMed, SpringerLink, Web of Science, and GeenMedical. Using 'Ginsenoside Rd', 'Ginsenosides', 'Anti-inflammation', 'Antioxidant', 'Apoptosis' and 'Neuroprotection' as keywords, the correlated literature was extracted and conducted from the databases mentioned above.

RESULTS

Through summarizing the existing research progress, we found that the general effects of ginsenoside Rd are anti-inflammatory, antioxidant, anti-apoptosis, inhibition of Ca²⁺ influx and protection of mitochondria, and through these pathways, the compound can inhibit excitatory toxicity, regulate nerve growth factor, and promote nerve regeneration.

CONCLUSION

Ginsenoside Rd is a promising natural neuroprotective agent. This review would contribute to the future development of ginsenoside Rd as a novel clinical candidate drug for treating neurological diseases.

Gardenia jasminoides Ellis Fruit Extracts Attenuated Colitis in 2,4,6-Trinitrobenzenesulfonic Acid-Induced Rats

Ulcerative colitis (UC) is a relapsing inflammatory disease with an unknown precise etiology. The purpose of this study is to investigate the protective effects of Gardenia jasminoides Ellis fruit extracts (GFE) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. GFE (50 mg/kg, 100 mg/kg) were administered orally for 7 days after induction. Meanwhile, the chemical components of GFE were performed by UPLC-QTOF-MS/MS. GFE significantly decreased DAI scores and ameliorated macroscopic and histologic damage. It also reduced the levels of MPO, NO, MDA, IL-1β, TNF-α, and IL-6, while increasing the level of SOD. Moreover, 56 components were identified in GFE using a UPLC-QTOF-MS/MS method, which can be categorized into six structural groups. Our results indicated that GFE has an ameliorative effect on TNBS-induced colitis in rats, which may further verify its anti-inflammatory and antioxidative properties. Therefore, GFE can be a promising protective agent of colitis that deserves further investigation.

Ginsenosides Rd monomer inhibits proinflammatory cytokines production and alleviates DSS-colitis by NF-κB and P38MAPK pathways in mice

BACKGROUND

Ulcerative colitis (UC) is dramatically increasing worldwide, cannot be thoroughly cured, and reduces patients' quality of life. Excessive activation of macrophages and over-production of cytokines play an important role in the pathogenesis of UC. Therefore, for its treatment, inhibiting macrophages' hyperactivation would be effective to develop new treatment approaches. Ginsenosides, extracted from ginseng, show an anti-inflammatory effect on the immunologic process. Our study used ginsenosides Rd monomer (GRd) to intervene in DSS-induced colitis mouse models and tested the immunological effect of macrophages.

METHOD

We observed body weights, weights of colons, colonic lengths, and inflammatory scores, as well as histological changes of DSS/DSS-GRd mice. We also isolated intestinal and peritoneal macrophages, performed qRT-PCR and ELISA to detect cytokines production by macrophages, and screened possible involved pathways by Western blotting.

RESULTS

Administering 20 mg/Kg GRd to DSS mice for 7-14 days reduced colonic inflammation. Moreover, both in vivo and in vitro, levels of TNF-α, IFN-γ, IL-6, IL-12/23p40, and IL-17A were all inhibited by GRd at 14 days in intestinal macrophages, and 20 μmol/L GRd at 12 h in peritoneal macrophages, respectively, but longer time made no more benefit. Western blotting showed GRd could decrease expression of pJNK, p-p38, pIκBα, and P65 in nuclear.

CONCLUSIONS

Our data indicate that GRd could down-regulate cytokines production in macrophages and alleviate DSS-colitis in mice, which may be related to NF-κB and P38MAPK pathways. These results suggest that GRd has an anti-inflammatory effect on experimental colitis and may have potential efficacy in the treatment of UC alone or in combination.

The promising therapeutic potentials of ginsenosides mediated through p38 MAPK signaling inhibition

The p38 mitogen-activated protein kinases (p38 MAPK) is a 38kD polypeptide recognized as the target for many potential anti-inflammatory agents. Accumulating evidence indicates that p38 MAPK could perform many roles in human disease pathophysiology. Therefore, great therapeutic benefits can be attained from p38 MAPK inhibitors. Ginseng is an exceptionally valued medicinal plant of the family Araliaceae (Panax genus). Recently, several studies targeted the therapeutic effects of purified individual ginsenoside, the most significant active ingredient of ginseng, and studied its particular molecular mechanism(s) of action rather than whole-plant extracts. Interestingly, several ginsenosides: ginsenosides compound K, F1, Rb1, Rb3, Rc, Rd, Re, Rf, Rg1, Rg2, Rg3, Rg5, Rh1, Rh2, Ro, notoginsenoside R1, and protopanaxadiol have shown to possess great therapeutic potentials mediated by their ability to downregulate p38 MAPK signaling in different cell lines and experimental animal models. Our review compiles the research findings of various ginsenosides as potent anti-inflammatory agents, highlighting the crucial role of p38 MAPK suppression in their pharmacological actions. In addition, in silico studies were conducted to explore the probable binding of these ginsenosides to p38 MAPK. The results obtained proposed p38 MAPK involvement in the beneficial pharmacological activities of ginsenosides in different ailments.

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p38 MAPK plays many roles in human disease pathophysiology. Therefore, great therapeutic benefits can be attained from p38 MAPK inhibitors.

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Several ginsenosides showed to possess great therapeutic potentials mediated by its ability to downregulate p38 MAPK signaling.

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in silico ​studies were conducted to explore the binding of these ginsenosides to p38 MAPK and evidenced the promising their inhibitory effect.

Lysimachiae Herba Inhibits Inflammatory Reactions and Improves Lipopolysaccharide/D-Galactosamine-Induced Hepatic Injury

This study aimed to determine the anti-inflammatory and hepatoprotective effects of Lysimachiae Herba ethanolic extract (LHE) in lipopolysaccharide (LPS)-stimulated macrophages and in a LPS/D-galactosamine (GalN)-induced acute hepatitis mouse model. Then, the production of inflammatory mediators and the activation of related pathways in macrophages were explored. Finally, we assessed the serum aminotransferase levels and the expression of inflammatory/antioxidant molecules in liver tissues in mice. Results revealed that LHE treatment significantly inhibited the production of inflammatory mediators in LPS-stimulated RAW 264.7 macrophages. Molecular data showed that LHE remarkably increased the activities of the antioxidant pathway and inhibited the phosphorylation of mitogen-activated protein kinase as well as the transcriptional activity of nuclear factor-κB induced by LPS. Furthermore, it prevented acute liver damage caused by LPS/D-GalN-induced hepatitis by inhibiting aminotransferase levels and histopathological changes in mice. Moreover, treatment with LHE significantly inhibited the activation of inflammatory pathways and increased the expression of antioxidant molecules including heme oxygenase-1/Nuclear factor erythroid 2-related factor 2. In conclusion, LHE has potent anti-inflammatory and hepatoprotective effects in LPS-stimulated macrophages and the LPS/D-GalN-induced acute hepatitis mouse model. Thus, it can be a treatment option for inflammation, hepatitis, and liver injury.

Natural Anti-Inflammatory Compounds as Drug Candidates for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) represents chronic recurrent intestinal inflammation resulting from various factors. Crohn’s disease (CD) and ulcerative colitis (UC) have been identified as the two major types of IBD. Currently, most of the drugs for IBD used commonly in the clinic have adverse reactions, and only a few drugs present long-lasting treatment effects. Moreover, issues of drug resistance and disease recurrence are frequent and difficult to resolve. Together, these issues cause difficulties in treating patients with IBD. Therefore, the development of novel therapeutic agents for the prevention and treatment of IBD is of significance. In this context, research on natural compounds exhibiting anti-inflammatory activity could be a novel approach to developing effective therapeutic strategies for IBD. Phytochemicals such as astragalus polysaccharide (APS), quercetin, limonin, ginsenoside Rd, luteolin, kaempferol, and icariin are reported to be effective in IBD treatment. In brief, natural compounds with anti-inflammatory activities are considered important candidate drugs for IBD treatment. The present review discusses the potential of certain natural compounds and their synthetic derivatives in the prevention and treatment of IBD.

An investigation of the anti-inflammatory effects of gabapentin on acetic acid-induced colitis in rats

Inflammatory bowel disease (IBD) is considered a chronic inflammatory gastrointestinal disease with treatment options which exhibit low efficacies and lead to considerable side effects. Hence, the challenge to alleviate IBD complications is remained to be resolved. The purpose of this study is evaluating anti-inflammatory impacts of gabapentin on acetic acid-induced colitis in rats. Colitis was induced by the instillation of 2 mL of 3% acetic acid solution into rat's colons. Rats were randomly allocated into six groups including normal group, colitis control group, gabapentin-treated groups (25, 50, and 100 mg/kg; i.p.), and dexamethasone-treated group (1 mg/kg; i.p.). Based on the macroscopic assessment besides histological and biochemical findings [myeloperoxidase (MPO), pro-inflammatory cytokines], the efficacy of gabapentin was investigated. Gabapentin (50 and 100 mg/kg), and dexamethasone considerably reduced macroscopic and microscopic colonic lesions induced by acetic acid in rats in comparison with colitis control group. These results were confirmed by reduced levels of MPO activity and colonic concentrations of interleukin-6, interleukin-1 beta, and tumor necrosis factor-alpha, in inflamed colon tissue. Our data demonstrated that gabapentin exerts profitable impacts in experimental colitis that might be ascribed to its anti-inflammatory features and thus can be a potential therapeutic agent for IBD treatment.

Identification and quantification of oleanane triterpenoid saponins and potential analgesic and anti-inflammatory activities from the roots and rhizomes of Panax stipuleanatus

BACKGROUND

Panax stipuleanatus represents a folk medicine for treatment of inflammation. However, lack of experimental data does not confirm its function. This article aims to investigate the analgesic and anti-inflammatory activities of triterpenoid saponins isolated from P. stipuleanatus.

METHODS

The chemical characterization of P. stipuleanatus allowed the identification and quantitation of two major compounds. Analgesic effects of triterpenoid saponins were evaluated in two models of thermal- and chemical-stimulated acute pain. Anti-inflammatory effects of triterpenoid saponins were also evaluated using four models of acetic acid-induced vascular permeability, xylene-induced ear edema, carrageenan-induced paw edema, and cotton pellet-induced granuloma in mice.

RESULTS

Two triterpenoid saponins of stipuleanosides R1 (SP-R1) and R2 (SP-R2) were isolated and identified from P. stipuleanatus. The results showed that SP-R1 and SP-R2 significantly increased the latency time to thermal pain in the hot plate test and reduced the writhing response in the acetic acid-induced writhing test. SP-R1 and SP-R2 caused a significant decrease in vascular permeability, ear edema, paw edema, and granuloma formation in inflammatory models. Further studies showed that the levels of inflammatory mediators, nitric oxide, malondialdehyde, tumor necrosis factor-α, and interleukin 6 in paw tissues were downregulated by SP-R1 and SP-R2. In addition, the rational harvest of three- to five-year-old P. stipuleanatus was preferable to obtain a higher level of triterpenoid saponins. SP-R2 showed the highest content in P. stipuleanatus, which had potential as a chemical marker for quality control of P. stipuleanatus.

CONCLUSION

This study provides important basic information about utilization of P. stipuleanatus resources for production of active triterpenoid saponins.

Ginsenoside from ginseng: a promising treatment for inflammatory bowel disease

Inflammatory bowel disease (IBD) is an autoimmune disease mediated by immune disorder and termed as one of the most refractory diseases by the Word Health Organization. Its morbidity has increased steadily over the past half century worldwide. Environmental, genetic, infectious, and immune factors are integral to the pathogenesis of IBD. Commonly known as the king of herbs, ginseng has been consumed in many countries for the past 2000 years. Its active ingredient ginsenosides, as the most prominent saponins of ginseng, have a wide range of pharmacological effects. Recent studies have confirmed that the active components of Panax ginseng have anti-inflammatory and immunomodulatory effects on IBD, including regulating the balance of immune cells, inhibiting the expression of cytokines, as well as activating Toll-like receptor 4, Nuclear factor-kappa B (NF-κB), nucleotide-binding oligomerization domain-like receptor (NLRP), mitogen-activated protein kinase signaling, and so on. Accumulated evidence indicates that ginsenosides may serve as a potential novel therapeutic drug or health product additive in IBD prevention and treatment in the future.

Targeting Mitogen-Activated Protein Kinases by Natural Products: A Novel Therapeutic Approach for Inflammatory Bowel Diseases

An increase in the prevalence of Inflammatory Bowel Diseases (IBD) as a multifactorial intestinal chronic inflammation as well as the absence of a certain cure, has created an innovative era in the management of IBD by molecule/pathway-based anti-inflammatory approaches. There are credible documentations that demonstrate Mitogen-Activated Protein Kinases (MAPK) acts as IBD regulator. Upon the activation of MAPK signalling pathway, the transcription and expression of various encoding inflammatory molecules implicated in IBD are altered, thereby exacerbating the inflammation development. The current pharmacological management of IBD, including drug and biological therapies are expensive, possess temporary relief and some adverse effects. In this context, a variety of dietary fruits or medicinal herbs have received worldwide attention versus the development of IBD. Infact, natural ingredients, such as Flavaglines, Fisetin, Myricitrin, Cardamonin, Curcumin, Octacosanol and Mangiferin possess protective and therapeutic effects against IBD via modulation of different segments of MAPK signaling pathway. This review paper calls attention to the role of MAPK signaling triggered by natural products in the prevention and treatment of IBD.

Biotransformation of Major Ginsenoside Rb1 to Rd by Dekkera anomala YAE-1 from Mongolian Fermented Milk (Airag)

Dekkera anomala YAE-1 strain separated from "airag" (Mongolian fermented mare's milk) produces β-glucosidase, which can convert ginsenoside Rb₁ from Panax ginseng. Ginseng-derived bioactive components such as ginsenoside Rb₁ have various immunological and anticancer activities. Airag was collected from five different mare milk farms located near Ulaanbaatar, Mongolia. YAE-1 strains were isolated from airag to examine the hydrolytic activities of β-glucosidase on Korean Panax ginseng using an API ZYM kit. Supernatants of selected cultures having β-glucosidase activity were examined for hydrolysis of the major ginsenoside Rb₁ at 40°C, pH 5.0. The YAE-1 strain was found to be nearly identical at 99.9% homology with Dekkera anomala DB-7B, and was thus named Dekkera anomala YAE-1. This strain exerted higher β-glucosidase activity than other enzymes. Reaction mixtures from Dekkera anomala YAE-1 showed great capacity for converting ginsenoside Rb₁ to ginsenoside Rd. The β-glucosidase produced by Dekkera anomala YAE-1 was able to hydrolyze ginsenoside Rb₁ and convert it to Rd during fermentation of the ginseng. The amount of ginsenoside Rd was highly increased from 0 to 1.404 mg/ml in fermented 20% ginseng root at 7 days.

Luteolin ameliorates experimental colitis in mice through ERK-mediated suppression of inflammation, apoptosis and autophagy

Ulcerative colitis (UC) is a chronic inflammatory disease with increasing incidence and prevalence worldwide. Currently used treatments of UC are unsatisfactory, while natural bioactive compounds are considered to be emerging therapeutic agents. Luteolin (Lut) is a natural compound with beneficial effects in a variety of diseases, however, its effect in UC has been poorly studied. In this study we investigated the effect of Lut in posttreatment and cotreatment of dextran sulfate sodium (DSS)-induced experimental colitis in mice. In addition, the role of extracellular signal-regulated kinases 1/2 (ERK1/2) in the mechanism of action of Lut in experimental colitis was investigated using the ERK inhibitor PD0325901. Lut attenuated symptoms of DSS-induced colitis in mice, ameliorated colon tissue damage and reduced inflammation, apoptosis and autophagy. The effect was more pronounced if Lut was administered simultaneously with DSS. The administration of ERK inhibitor exacerbated DSS-induced colitis symptoms and prevented the protective effects of Lut. The results provide new mechanistic details underlying the anti-inflammatory, anti-apoptotic and anti-autophagic effects of Lut through the activation of the ERK signaling pathway. This suggested that Lut can be used as a novel therapeutic candidate in the treatment of UC or could be used as a supplement to existing therapy.

Sturgeon hydrolysates alleviate DSS-induced colon colitis in mice by modulating NF-κB, MAPK, and microbiota composition

Sturgeon muscle byproduct collected after caviar production is usually not fully utilized, and sometimes may be discarded, thus causing a lot of waste. Yet dietary protein hydrolysates, which may be derived from sturgeon muscle, have been reported to have versatile beneficial biological activities. Studying the biological activities of sturgeon muscle-derived hydrolysates holds much promise for adding value to sturgeon. The current study aimed to study the therapeutic anti-inflammatory effects of sturgeon muscle-derived hydrolysates and the underlying mechanisms. The administration of sturgeon hydrolysates (SH) significantly decreased the severity of DSS-induced damage, evidenced by increased body weight, colon length, and decreased disease activity index (DAI) and histological scores. SH also inhibited myeloperoxidase (MPO) activity and reduced the serum levels of IL-6, IL-1β, and TNF-α. Western blotting results revealed that SH suppressed DSS-induced activation of the NF-κB and MAPK pathways in the colon. Furthermore, SH partially restored the alteration of the gut microbiota in colitic mice. SH increased the Bacteroidetes/Firmicutes ratio and the relative abundance of Ruminococcaceae, Porphyromonadaceae, and Bacteroidetes S24-7, while decreased the abundance of potentially harmful bacteria Erysipelotrichaceae and Enterococcaceae. These results suggest that SH inhibited DSS-induced colitis by regulating the NF-κB and MAPK pathways and modulating microbiota composition.

Traditional Chinese Medicine: Role in Reducing β-Amyloid, Apoptosis, Autophagy, Neuroinflammation, Oxidative Stress, and Mitochondrial Dysfunction of Alzheimer's Disease

Alzheimer's disease (AD) is a progressive age-related neurodegenerative disease characterized by memory loss and cognitive impairment. The major characteristics of AD are amyloid β plaques, apoptosis, autophagy dysfunction, neuroinflammation, oxidative stress, and mitochondrial dysfunction. These are mostly used as the significant indicators for selecting the effects of potential drugs. It is imperative to explain AD pathogenesis and realize productive treatments. Although the currently used chemical drugs for clinical applications of AD are effective in managing the symptoms, they are inadequate to achieve anticipated preventive or therapeutic outcomes. There are new strategies for treating AD. Traditional Chinese Medicine (TCM) has accumulated thousands of years of experience in treating dementia. Nowadays, numerous modern pharmacological studies have verified the efficacy of many bioactive ingredients isolated from TCM for AD treatment. In this review, representative TCM for the treatment of AD are discussed, and among these herbal medicines, the Lamiaceae family accounts for the highest proportion. It is concluded that monomers and extracts from TCM have potential therapeutic effect for AD treatment.

Natural Products: Experimental Efficient Agents for Inflammatory Bowel Disease Therapy

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Inflammatory bowel disease (IBD) is a chronic, elusive disorder resulting in relapsing inflammation of intestine with incompletely elucidated etiology, whose two representative forms are ulcerative colitis (UC) and Crohn’s disease (CD). Accumulating researches have revealed that the individual genetic susceptibility, environmental risk elements, intestinal microbial flora, as well as innate and adaptive immune system are implicated in the pathogenesis and development of IBD. Despite remarkable progression of IBD therapy has been achieved by chemical drugs and biological therapies such as aminosalicylates, corticosteroids, antibiotics, anti-tumor necrosis factor (TNF)-α, anti-integrin agents, etc., healing outcome still cannot be obtained, along with inevitable side effects. Consequently, a variety of researches have focused on exploring new therapies, and found that natural products (NPs) isolated from herbs or plants may serve as promising therapeutic agents for IBD through antiinflammatory, anti-oxidant, anti-fibrotic and anti-apoptotic effects, which implicates the modulation on nucleotide- binding domain (NOD) like receptor protein (NLRP) 3 inflammasome, gut microbiota, intestinal microvascular endothelial cells, intestinal epithelia, immune system, etc. In the present review, we will summarize the research development of IBD pathogenesis and current mainstream therapy, as well as the therapeutic potential and intrinsic mechanisms of NPs in IBD.

Protection by pure and genistein fortified extra virgin olive oil, canola oil, and rice bran oil against acetic acid-induced ulcerative colitis in rats

Conjugation of genistein and dietary oils improves the anti-inflammatory and antioxidant effects of genistein on colitis in rats.

Neuroprotective Effects of Ginseng Phytochemicals: Recent Perspectives

As our global population ages, the treatment of neurodegenerative diseases is critical to our society. In recent years, researchers have begun to study the role of biologically active chemicals from plants and herbs to gain new inspiration and develop new therapeutic drugs. Ginseng (Panax ginseng C.A. Mey.) is a famous Chinese herbal medicine with a variety of pharmacological activities. It has been used to treat various diseases since ancient times. Extensive research over the years has shown that ginseng has potential as a neuroprotective drug, and its neuroprotective effects can be used to treat and prevent neurological damage or pathologically related diseases (such as Alzheimer's disease, Parkinson's disease, Huntington's disease, depression symptoms, and strokes). Moreover, evidence for the medicinal and health benefits of ginsenoside, its main active ingredient, in the prevention of neurodegenerative diseases is increasing, and current clinical results have not reported any serious adverse reactions to ginseng. Therefore, we briefly review the recent research and development on the beneficial effects and mechanisms of ginseng and its main active ingredient, ginsenoside, in the prevention and treatment of neurodegenerative diseases, hoping to provide some ideas for the discovery and identification of ginseng neuroprotection.

Supercritical Fluid Extract of Angelica sinensis and Zingiber officinale Roscoe Ameliorates TNBS-Induced Colitis in Rats

Inflammatory bowel disease (IBD) is a worldwide healthcare problem calling for the development of new therapeutic drugs. Angelica sinensis and Zingiber officinale Roscoe are two common dietetic Chinese herbs, which are traditionally used for complementary treatment of gastrointestinal disorders. As bioactive constituents, volatile and pungent substances of these two herbs could be effectively extracted together by supercritical fluid extraction. In this study, the supercritical fluid extract of Angelica sinensis and Zingiber officinale Roscoe (AZ-SFE) was obtained by an optimized extraction process and it was chemically characterized. The anti-inflammatory effect and underlying mechanism of AZ-SFE were evaluated in a lipopolysaccharide (LPS)-induced RAW264.7 cell model and a 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-induced colitis rat model. AZ-SFE notably inhibited the production of NO in LPS-stimulated macrophages, and it inhibited the proliferation of Concanavalin A (Con A)-induced splenocytes with suppression of the Th1 immune response. In vivo, the study demonstrated that AZ-SFE significantly alleviated disease activity, colonic shortening, macroscopic damage and histological injury of TNBS-treated rats with reduction of oxidative stress, suppression of inflammatory cytokines, and modulation of hepcidin and serum iron. These findings suggested that AZ-SFE may be a promising supplement for current IBD therapy.

Acute and genetic toxicity of GS-E3D, a new pectin lyase-modified red ginseng extract

Korean red ginseng and its extract have been used as traditional medicines and functional foods in countries worldwide. Pectin lyase-modified red ginseng extract (GS-E3D) was newly developed as a dietary supplement for obesity, diabetes-related renal dysfunction, etc. In this study, the safety of GS-E3D on acute toxicity and genotoxicity was evaluated. For acute study, Sprague-Dawley rats were administrated by oral gavage at a dose of 5000 mg/kg GS-E3D. To evaluate genotoxicity of GS-E3D, we conducted three-battery tests, which are Ames test using Escherichia coli (WP2uvrA pKM101) and Salmonella typhimurium strains (TA98, TA100, TA1535 and TA1537), chromosomal aberration test -using Chinese hamster lung cells, and micronucleus test using ICR mice. In acute toxicity studies, there were no dead animals or abnormal necropsy findings in the control group and GS-E3D (5000 mg/kg) treated group. GS-E3D did not induce mutagenicity in the bacterial test, chromosomal aberrations in Chinese hamster lung cells and micronuclei in bone marrow cells of mice. Conclusively, the approximate lethal dose of GS-E3D was greater than 5000 mg/kg bw and GS-E3D has no genotoxic potential in the three-battery tests on genotoxicity.

Madecassoside prevents acute liver failure in LPS/D-GalN-induced mice by inhibiting p38/NF-κB and activating Nrf2/HO-1 signaling

Madecassoside (MA), a triterpenoid saponin isolated from Centella asiatica, exerts various pharmacological activities including antioxidative and anti-inflammatory effects. The aim of this study was to explore the protective effect of MA in the treatment of lipopolysaccharide (LPS) and D-galactosamine (D-GalN)-induced acute liver failure(ALF) in mice. We hypothesized that MA administration may decrease the degree of liver injury caused by LPS/D-GalN. In this study, we investigated this hypothesis by treating a mouse model of LPS/D-GalN-induced liver injury with MA. Our study demonstrated that MA (20 mg/kg and 40 mg/kg) treatment for 10 days attenuated LPS/D-GalN-induced liver injury by protecting liver function, suppressing the production of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and recovering antioxidant enzyme activity. MA also significantly suppressed LPS-stimulated protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 by blocking the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and eukaryotic transcription factor nuclear factor-kappa B (NF-κB). In addition, MA treatment enhanced protein levels of heme oxygenase (HO)-1 and anti-oxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) through the upregulation of nuclear factor E2-related factor 2 (Nrf2) in LPS-stimulated liver injury. These results suggest that MA is a promising agent for the treatment of LPS/D-GalN-induced liver injury that could serve as a candidate for the development of a hepatoprotective drug against ALF.

Characterization of Paenibacillus sp. MBT213 Isolated from Raw Milk and Its Ability to Convert Ginsenoside Rb1 into Ginsenoside Rd from Panax ginseng

This study was conducted to isolate and characterize Paenibacillus sp. MBT213 possessing β-glucosidase activity from raw milk, and examine the enzymatic capacity on the hydrolysis of a major ginsenoside (Rb₁). Strain MBT213 was found to have a high hydrolytic ability on ginsenoside Rb₁ by Esculin Iron Agar test. 16S rDNA analysis revealed that MBT213 was Paenibacillu sp. Crude enzyme of MBT213 strain exhibited high conversion capacity on ginsenoside Rb1 into ginsenoside Rd proven by TLC and HPLC analyses. The API ZYM kit confirmed that Paenibacillu sp. MBT213 exerted higher β-glucosidase and β-galactosidase activity than other strains. Optimum pH and temperature for crude enzyme were found at 7.0 and 35°C in hydrolysis of ginsenoside Rb₁. After 10 d of optimal reaction conditions for the crude enzyme, ginsenoside Rb₁ fully converted to ginsenoside Rd. Ginseng roots (20%) were fermented for 14 d, and analyzed by HPLC showed that amount of ginsenoside Rb1 significantly decreased, while that of ginsenoside Rd was significantly increased. The study confirmed that the β-glucosidase produced by Paenibacillus sp. MBT213 can hydrolyze the major ginsenoside Rb1 and convert to Rd during fermentation of the ginseng. The β-glucosidase activity of this novel Paenibacillus sp. MBT213 strain may be utilized in development of variety of health foods, dairy foods and pharmaceutical products.

A mechanistic review on plant-derived natural compounds as dietary supplements for prevention of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a recurrent idiopathic inflammatory condition, characterized by disruption of the gut mucosal barrier. This mechanistic review aims to highlight the significance of plant-derived natural compounds as dietary supplements, which can be used in addition to restricted conventional options for the prevention of IBD and induction of remission. Various clinical trials confirmed the effectiveness and tolerability of natural supplements in patients with IBD. Mounting evidence suggests that these natural compounds perform their protective and therapeutic effect on IBD through numerous molecular mechanisms, including anti-inflammatory and immunoregulatory, anti-oxidative stress, modulation of intracellular signaling transduction pathways, as well as improving gut microbiota. In conclusion, natural products can be considered as dietary supplements with therapeutic potential for IBD, provided that their safety and efficacy is confirmed in future well-designed clinical trials with adequate sample size.

Neuroprotective Effect of Ginsenoside Rd in Spinal Cord Injury Rats

In this study, the neuroprotective effects of ginsenoside Rd (GS Rd) were evaluated in a rat model of spinal cord injury (SCI). Rats in SCI groups received a T8 laminectomy and a spinal contusion injury. GS Rd 12.5, 25 and 50 mg/kg were administered intraperitoneally 1 hr before the surgery and once daily for 14 days. Dexamethasone 1 mg/kg was administered as a positive control. Locomotor function was evaluated using the BBB score system. H&E staining and Nissl staining were performed to observe the histological changes in the spinal cord. The levels of MDA and GSH and the activity of SOD were assessed to reflect the oxidative stress state. The production of TNF-α, IL-1β and IL-1 was assessed using ELISA kits to examine the inflammatory responses in the spinal cord. TUNEL staining was used to detect the cell apoptosis in the spinal cord. Western blot analysis was used to examine the expression of apoptosis-associated proteins and MAPK proteins. The results demonstrated that GS Rd 25 and 50 mg/kg significantly improved the locomotor function of rats after SCI, reduced tissue injury and increased neuron survival in the spinal cord. Mechanically, GS Rd decreased MDA level, increased GSH level and SOD activity, reduced the production of pro-inflammatory cytokines and prevented cell apoptosis. The effects were equivalent to those of dexamethasone. In addition, GS Rd effectively inhibited the activation of MAPK signalling pathway induced by SCI, which might be involved in the protective effects of GS Rd against SCI. In conclusion, GS Rd attenuates SCI-induced secondary injury through reversing the redox-state imbalance, inhibiting the inflammatory response and apoptosis in the spinal cord tissue.

Ocotillol, a Majonoside R2 Metabolite, Ameliorates 2,4,6-Trinitrobenzenesulfonic Acid-Induced Colitis in Mice by Restoring the Balance of Th17/Treg Cells

In a preliminary experiment, majonoside R2 (MR2), isolated from Vietnamese ginseng (Panax vietnamensis Ha et Grushv.), inhibited differentiation to Th17 cells and was metabolized to ocotillol via pseudoginsenoside RT4 (PRT4) by gut microbiota. Therefore, we examined the inhibitory effects of MR2 and its metabolites PRT4 and ocotillol against Th17 cell differentiation. These ginsenosides significantly suppressed interleukin (IL)-6/tumor growth factor beta-induced differentiation of splenic CD4(+) T cells into Th17 cells and expression of IL-17 in vitro. Among these ginsenosides, ocotillol showed the highest inhibitory effect. We also examined the anti-inflammatory effect of ocotillol in mice with 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. Oral administration of ocotillol significantly suppressed TNBS-induced colon shortening, macroscopic score, myeloperoxidase activity, and production of nitric oxide and prostaglandin E2. Ocotillol treatment increased TNBS-suppressed expression of tight junction proteins ZO-1, occludin, and claudin-1 in the colon. Treatment with ocotillol inhibited TNBS-induced expression of tumor necrosis factor (TNF)-α and IL-1β, as well as activation of NF-κB and MAPKs. Moreover, treatment with ocotillol inhibited TNBS- induced differentiation to Th17 cells in the lamina propria of colon, as well as expression of T-bet, RORγt, IL-17, and IL-23. Ocotillol treatment also increased Treg cell differentiation and Foxp3 and IL-10 expression. These findings suggest that orally administered MR2 may be metabolized to ocotillol in the intestine by gut microbiota and the transformed ocotillol may ameliorate inflammatory diseases such as colitis by restoring the balance of Th17/Treg cells.

Anti-inflammatory effects of ginsenoside Rg1 and its metabolites ginsenoside Rh1 and 20(S)-protopanaxatriol in mice with TNBS-induced colitis

Ginsenoside Rg1, one of the main constituents of Panax ginseng, exhibits anti-inflammatory effect. In a preliminary study, it was observed that ginsenoside Rg1 was metabolized to 20(S)-protopanaxtriol via ginsenosides Rh1 and F1 by gut microbiota. We further investigated the anti-inflammatory effects of ginsenoside Rg1 and its metabolites in vitro and in vivo. Ginsenosides Rg1, Rh1, and 20(S)-protopanaxtriol inhibited the activation of NF-κB activation, phosphorylation of transforming growth factor beta-activated kinase 1 and interleukin (IL)-1 receptor-associated kinase, and expression of tumor necrosis factor-α and IL-1β in lipopolysaccharide (LPS)-stimulated macrophages. They also inhibited the binding of LPS to toll-like receptor 4 on the macrophages. Orally administered ginsenoside Rg1, Rh1, or 20(S)-protopanaxtriol inhibited 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colon shortening, myeloperoxidase activity, and expression of IL-1β, IL-17, and tumor necrosis factor-α in mice with TNBS-induced colitis. They did not only inhibit TNBS-induced NF-κB activation, but also restored TNBS-induced Th17/Treg imbalance. They restored IL-10 and Foxp3 expression. Moreover, they inhibited Th17 cell differentiation in vitro. Of these metabolites, in vitro and in vivo anti-inflammatory effect of 20(S)-protopanaxtriol was the most potent, followed by Rh1. These findings suggest that ginsenoside Rg1 is metabolized to 20(S)-protopanaxtriol via ginsenosides Rh1 and F1 and these metabolites particularly 20(S)-protopanaxtriol, may ameliorate inflammatory disease such as colitis by inhibiting the binding of LPS to TLR4 on macrophages and restoring the Th17/Treg imbalance.

Beneficial effects of the traditional medicine Igongsan and its constituent ergosterol on dextran sulfate sodium-induced colitis in mice

Ulcerative colitis (UC) is a type of inflammatory bowel disease and is considered a chronic gastrointestinal disorder. Igongsan (IGS) is a Korean herbal medicine, which has been used to treat digestive disorders. However, the ameliorative effect and molecular mechanisms of IGS in intestinal inflammation have not yet been studied in detail. The present study aimed to investigate the protective effects of IGS and its constituent, ergosterol, in a mouse model of dextran sulfate sodium (DSS)‑induced colitis. Colitis was induced in mice by supplementing their drinking water with 5% (w/v) DSS for 7 days. The effects of IGS were then determined on DSS‑induced clinical signs of colitis, including weight loss, colon shortening, diarrhea and obscure/gross bleeding. In addition, the effects of IGS were determined on the expression levels of inflammation‑associated genes in the colon tissue of DSS‑treated mice. The results of the present study demonstrated that mice treated with DSS exhibited marked clinical symptoms, including weight loss and reduced colon length. Treatment with IGS attenuated these symptoms and also suppressed the expression levels of tumor necrosis factor‑α and interleukin‑6, as well as the expression of cyclooxygenase‑2 in the colon tissue of DSS‑treated mice. IGS also reduced the activation of the transcription factor nuclear factor‑κB p65 in the colon tissue of DSS‑treated mice. In addition, ergosterol was shown to attenuate the DSS‑induced clinical symptoms of colitis in mice. In conclusion, the present study provided experimental evidence that IGS may be a useful therapeutic drug for patients with UC.

Effect of a soluble prebiotic fiber, NUTRIOSE, on the absorption of ginsenoside Rd in rats orally administered ginseng

Background

There is limited understanding of the effect of dietary components on the absorption of ginsenosides and their metabolites into the blood.

Methods

This study investigated the pharmacokinetics of the ginseng extract and its main constituent ginsenoside Rb1 in rats with or without pretreatment with a prebiotic fiber, NUTRIOSE, by liquid chromatography tandem mass spectrometry. When ginsenoside Rb1 was incubated with rat feces, its main metabolite was ginsenoside Rd.

Results

When the intestinal microbiota of rat feces were cultured in vitro, their ginsenoside Rd-forming activities were significantly induced by NUTRIOSE. When ginsenoside Rb1 was orally administered to rats, the maximum plasma concentration (Cmax) and area under the plasma drug concentration–time curve (AUC) for the main metabolite, ginsenoside Rd, were 72.4 ± 31.6 ng/mL and 663.9 ± 285.3 μg·h/mL, respectively. When the ginseng extract (2,000 mg/kg) was orally administered, Cmax and AUC for ginsenoside Rd were 906.5 ± 330.2 ng/mL and 11,377.3 ± 4,470.2 μg·h/mL, respectively. When ginseng extract was orally administered to rats fed NUTRIOSE containing diets (2.5%, 5%, or 10%), Cmax and AUC were increased in the NUTRIOSE receiving groups in a dose-dependent manner.

Conclusion

These findings reveal that intestinal microflora promote metabolic conversion of ginsenoside Rb1 and ginseng extract to ginsenoside Rd and promote its absorption into the blood in rats. Its conversion may be induced by prebiotic diets such as NUTRIOSE.

Ginsenoside Rd for acute ischemic stroke: translating from bench to bedside

Numerous studies have identified pathophysiological mechanisms of acute ischemic stroke and have provided proof-of-principle evidence that strategies designed to impede the ischemic cascade, namely neuroprotection, can protect the ischemic brain. However, the translation of these therapeutic agents to the clinic has not been successful. Ginsenoside Rd, a dammarane-type steroid glycoside extracted from ginseng plants, has exhibited an encouraging neuroprotective efficacy in both laboratory and clinical studies. This article attempts to provide a synopsis of the physiochemical profile, pharmacokinetics, pharmacodynamics, clinical efficacy, safety and putative therapeutic mechanisms of Rd. Finally, the authors discuss the validity of Rd as a neuroprotective agent for acute ischemic stroke.

Inhibitory effect of the gallotannin corilagin on dextran sulfate sodium-induced murine ulcerative colitis

The therapeutic effect of corilagin (1) was evaluated in an acute colitis model induced by dextran sulfate sodium (DSS) in mice, and the mechanism of action was investigated in this study. Animals were challenged with 2% DSS drinking water for 5 consecutive days and then intraperitoneally treated with 1 (7.5, 15, and 30 mg/kg) daily for 7 days. It was found that 1 significantly decreased the disease activity index, inhibited the shortening of colon length, reduced colon tissue damage, and suppressed myeloperoxidase activity. Moreover, 1 greatly suppressed the secretion of TNF-α, IL-6, and IL-1β, inhibited the degradation of IκB α, and down-regulated expression of cleaved caspase-3 and cleaved caspase-9 in colon tissues of DSS-treated mice. These findings demonstrated that 1 exerts a protective effect on DSS-induced colitis, and its underlying mechanisms are associated with inhibition of the NF-κB pathway that mitigates colon inflammatory responses and apoptosis of intestinal epithelial cells.

Biochemical basis of cancer chemoprevention and/or chemotherapy with ginsenosides (Review)

Cancer still imposes a global threat to public health. After decades of research on cancer biology and enormous efforts in developing anticancer therapies, we now understand that the majority of cancers can be prevented. Bioactive phytochemicals present in edible plants have been shown to reduce the risk of various types of cancer. Ginseng (Panax ginseng C.A. Meyer), which contains a wide variety of saponins, known as ginsenosides, is an age-old remedy for human ailments, including cancer. Numerous laboratory-based studies have revealed the anticancer properties of ginsenosides, which compel tumor cells to commit suicide, arrest the proliferation of cancer cells in culture and inhibit experimentally-induced tumor formation in laboratory animals. Ginsenosides have been reported to inhibit tumor angiogenesis, as well as the invasion and metastasis of various types of cancer cells. Moreover, ginsenosides as combination therapy enhance the sensitivity of chemoresistant tumors to clinically used chemotherapeutic agents. This review sheds light on the molecular mechanisms underlying the cancer chemopreventive and/or chemotherapeutic activity of ginsenosides and their intestinal metabolites with particular focus on the modulation of cell signaling pathways associated with oxidative stress, inflammation, cell proliferation, apoptosis, angiogenesis and the metastasis of cancer cells.

Involvement of 5HT3 Receptors in Anti-Inflammatory Effects of Tropisetron on Experimental TNBS-Induced Colitis in Rat

INTRODUCTION

There is a pressing need for research leading to the development of new effective drugs with lower side effects and more efficacy for treating inflammatory bowel disease (IBD). The analgesic and anti-inflammatory properties of 5-Hydroxytryptamine (5-HT)-3 receptor antagonists have been shown in in vivo and in vitro studies. The present study was designed to investigate the effects of tropisetron, a 5-HT3 receptor antagonist, on an immune-based animal model of IBD.

METHODS

In the present study, the trinitrobenzenesulfonic acid (TNBS) model of colitis in the rat was used. Two hours after induction of colitis in rats, tropisetron (2 mg/kg), dexamethasone (1 mg/kg), meta-chlorophenylbiguanide (mCPBG, 5 mg/kg), a 5-HT3 receptor agonist, or tropisetron + mCPBG were intraperitoneally (i.p.) administrated for 6 days. Animals were then sacrificed; macroscopic, histological, biochemical (myeloperoxidase [MPO]) assessments and ELISA test (tumor necrosis factor-alpha, interleukin-6 and interleukin-1 beta) were performed on distal colon samples.

RESULTS

Tropisetron or dexamethasone treatment significantly reduced macroscopic and microscopic colonic damages. In addition, a significant reduction in MPO activity and colonic levels of inflammatory cytokines was seen. The beneficial effects of tropisetron were antagonized by concurrent administration of mCPBG.

CONCLUSION

The present study indicates that the protective effects of tropisetron on TNBS-induced colitis can be mediated by 5-HT3 receptors.

Ginsenoside Rd attenuates beta-amyloid-induced tau phosphorylation by altering the functional balance of glycogen synthase kinase 3beta and protein phosphatase 2A

Neurofibrillary tangles are aggregates of hyperphosphorylated tau that are one of the pathological hallmarks of Alzheimer's disease (AD). Tau phosphorylation is regulated by a balance of kinase and phosphatase activities. Our previous study has demonstrated that ginsenoside Rd, one of the principal active ingredients of Pana notoginseng, inhibits okadaic acid-induced tau phosphorylation in vivo and in vitro, but the underlying mechanism(s) is unknown. In this study, we showed that ginsenoside Rd pretreatment inhibited tau phosphorylation at multiple sites in beta-amyloid (Aβ)-treated cultured cortical neurons, and in vivo in both a rat and transgenic mouse model. Ginsenoside Rd not only reduced Aβ-induced increased expression of glycogen synthase kinase 3beta (GSK-3β), the most important kinase involved in tau phosphorylation, but also inhibited its activity by enhancing and attenuating its phosphorylation at Ser9 and Tyr216, respectively. Moreover, ginsenoside Rd enhanced the activity of protein phosphatase 2A (PP-2A), a key phosphatase involved in tau dephosphorylation. Finally, an in vitro biochemical assay revealed that ginsenoside Rd directly affected GSK-3β and PP-2A activities. Thus, our findings provide the first evidence that ginsenoside Rd attenuates Aβ-induced pathological tau phosphorylation by altering the functional balance of GSK-3β and PP-2A.

Ginsenoside Rd maintains adult neural stem cell proliferation during lead-impaired neurogenesis

Lead exposure attracts a great deal of public attention due to its harmful effects on human health. Even low-level lead (Pb) exposure reduces the capacity for neurogenesis. It is well known that microglia-mediated neurotoxicity can impair neurogenesis. Despite this, few in vivo studies have been conducted to understand the relationship between acute Pb exposure and microglial activation. We investigated whether the acute Pb exposure altered the expression of a marker of activated microglial cells (Iba-1), and markers of neurogenesis (BrdU and doublecortin) in aging rats. As compared to controls, Pb exposure significantly enhanced the expression of Iba-1 immunoreactivity; increased the expression levels of IL-1β, IL-6, and TNF-α and decreased the numbers of BrdU(+) and doublecortin(+) cells. Our prior work demonstrated that ginsenoside Rd (Rd), one of the major active ingredients in Panax ginseng, was neuroprotective in a variety of paradigms involving anti-inflammatory mechanisms. Thus, we further examined whether Rd could attenuate Pb-induced phenotypes. Compared with the Pb exposure group, Rd pretreatment indeed attenuated the effects of Pb exposure. These results suggest that Rd may be neuroprotective in old rats following acute Pb exposure, which involves limitation of microglial activation and maintenance of NSC proliferation.