Ginsenoside Rb1 inhibits cell activation and liver fibrosis in rat hepatic stellate cells

Ginsenoside Rb1 induces hepatic stellate cell ferroptosis to alleviate liver fibrosis via the BECN1/SLC7A11 axis

Liver fibrosis is primarily driven by the activation of hepatic stellate cells (HSCs), a process associated with ferroptosis. Ginsenoside Rb1 (GRb1), a major active component extracted from Panax ginseng, inhibits HSC activation. However, the potential role of GRb1 in mediating HSC ferroptosis remains unclear. This study examined the effect of GRb1 on liver fibrosis both in vivo and in vitro, using CCl4-induced liver fibrosis mouse model and primary HSCs, LX-2 cells. The findings revealed that GRb1 effectively inactivated HSCs in vitro, reducing alpha-smooth muscle actin (α-SMA) and Type I collagen (Col1A1) levels. Moreover, GRb1 significantly alleviated CCl4-induced liver fibrosis in vivo. From a mechanistic standpoint, the ferroptosis pathway appeared to be central to the antifibrotic effects of GRb1. Specifically, GRb1 promoted HSC ferroptosis both in vivo and in vitro, characterized by increased glutathione depletion, malondialdehyde production, iron overload, and accumulation of reactive oxygen species (ROS). Intriguingly, GRb1 increased Beclin 1 (BECN1) levels and decreased the System Xc-key subunit SLC7A11. Further experiments showed that BECN1 silencing inhibited GRb1-induced effects on HSC ferroptosis and mitigated the reduction of SLC7A11 caused by GRb1. Moreover, BECN1 could directly interact with SLC7A11, initiating HSC ferroptosis. In conclusion, the suppression of BECN1 counteracted the effects of GRb1 on HSC inactivation both in vivo and in vitro. Overall, this study highlights the novel role of GRb1 in inducing HSC ferroptosis and promoting HSC inactivation, at least partly through its modulation of BECN1 and SLC7A11.

Mechanism and Progress of Natural Products in the Treatment of NAFLD-Related Fibrosis

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most prevalent chronic liver disorder worldwide, with liver fibrosis (LF) serving as a pivotal juncture in NAFLD progression. Natural products have demonstrated substantial antifibrotic properties, ushering in novel avenues for NAFLD treatment. This study provides a comprehensive review of the potential of natural products as antifibrotic agents, including flavonoids, polyphenol compounds, and terpenoids, with specific emphasis on the role of Baicalin in NAFLD-associated fibrosis. Mechanistically, these natural products have exhibited the capacity to target a multitude of signaling pathways, including Hedgehog, Wnt/β-catenin, TGF-β1, and NF-κB. Moreover, they can augment the activities of antioxidant enzymes, inhibit pro-fibrotic factors, and diminish fibrosis markers. In conclusion, this review underscores the considerable potential of natural products in addressing NAFLD-related liver fibrosis through multifaceted mechanisms. Nonetheless, it underscores the imperative need for further clinical investigation to authenticate their effectiveness, offering invaluable insights for future therapeutic advancements in this domain.

Ginsenoside Rb1 from Panax notoginseng Suppressed TNF-α-Induced Matrix Metalloproteinase-9 via the Suppression of Double-Strand RNA-Dependent Protein Kinase (PKR)/NF-κB Pathway

Chronic inflammation is commonly accompanied by the stimulation of matrix metalloproteinases (MMPs) production and the degradation of the extracellular matrix. The overexpression of MMP-9 (Gelatinase B) highly participates in the progression of pathetic cardiac remodeling and liver cancer metastasis. Panax notoginseng (Burkill) F. H. Chen (Sanqi), a widely used traditional Chinese medicinal herb, shows myocardial protective and anti-tumor effects. In this study, we examined the inhibitory effect of different PNG extracts on tumor necrosis factor (TNF)-α-induced MMP-9 expression in cardiac myoblast H9c2 cells. Using a bioassay-guided fractionation scheme, the most active extract was fractionated by silica gel column chromatography and high-performance liquid chromatography until an active compound was obtained. The compound was identified as Ginsenoside Rb1 by nuclear magnetic resonance. Ginsenoside Rb1 inhibited TNF-α-induced MMP-9 production in both H9c2 and liver carcinoma HepG-2 cells. Interestingly, it did not affect the MMP-2 (Gelatinase A) level and the cell proliferation of the two cell lines. The inhibitory effects of Ginsenoside Rb1 may be due to its modulation of double-strand RNA-dependent protein kinase and nuclear factor kappa B signaling pathways. The results reveal the potential use of Ginsenoside Rb1 for the treatment of inflammatory and MMP-9-related cardiac remodeling and metastasis of hepatocellular carcinomas.

Traditional Chinese medicine: An important source for discovering candidate agents against hepatic fibrosis

Hepatic fibrosis (HF) refers to the pathophysiological process of connective tissue dysplasia in the liver caused by various pathogenic factors. Nowadays, HF is becoming a severe threat to the health of human being. However, the drugs available for treating HF are limited. Currently, increasing natural agents derived from traditional Chinese medicines (TCMs) have been found to be beneficial for HF. A systemic literature search was conducted from PubMed, GeenMedical, Sci-Hub, CNKI, Google Scholar and Baidu Scholar, with the keywords of “traditional Chinese medicine,” “herbal medicine,” “natural agents,” “liver diseases,” and “hepatic fibrosis.” So far, more than 76 natural monomers have been isolated and identified from the TCMs with inhibitory effect on HF, including alkaloids, flavones, quinones, terpenoids, saponins, phenylpropanoids, and polysaccharides, etc. The anti-hepatic fibrosis effects of these compounds include hepatoprotection, inhibition of hepatic stellate cells (HSC) activation, regulation of extracellular matrix (ECM) synthesis & secretion, regulation of autophagy, and antioxidant & anti-inflammation, etc. Natural compounds and extracts from TCMs are promising agents for the prevention and treatment of HF, and this review would be of great significance to development of novel drugs for treating HF.

The osteogenesis of Ginsenoside Rb1 incorporated silk/micro-nano hydroxyapatite/sodium alginate composite scaffolds for calvarial defect

Ginsenoside Rb1, the effective constituent of ginseng, has been demonstrated to play favorable roles in improving the immunity system. However, there is little study on the osteogenesis and angiogenesis effect of Ginsenoside Rb1. Moreover, how to establish a delivery system of Ginsenoside Rb1 and its repairment ability in bone defect remains elusive. In this study, the role of Ginsenoside Rb1 in cell viability, proliferation, apoptosis, osteogenic genes expression, ALP activity of rat BMSCs were evaluated firstly. Then, micro-nano HAp granules combined with silk were prepared to establish a delivery system of Ginsenoside Rb1, and the osteogenic and angiogenic effect of Ginsenoside Rb1 loaded on micro-nano HAp/silk in rat calvarial defect models were assessed by sequential fluorescence labeling, and histology analysis, respectively. It revealed that Ginsenoside Rb1 could maintain cell viability, significantly increased ALP activity, osteogenic and angiogenic genes expression. Meanwhile, micro-nano HAp granules combined with silk were fabricated smoothly and were a delivery carrier for Ginsenoside Rb1. Significantly, Ginsenoside Rb1 loaded on micro-nano HAp/silk could facilitate osteogenesis and angiogenesis. All the outcomes hint that Ginsenoside Rb1 could reinforce the osteogenesis differentiation and angiogenesis factor’s expression of BMSCs. Moreover, micro-nano HAp combined with silk could act as a carrier for Ginsenoside Rb1 to repair bone defect.

Hepatoprotective Potency of Chrysophanol 8-O-Glucoside from Rheum palmatum L. against Hepatic Fibrosis via Regulation of the STAT3 Signaling Pathway

Rhubarb is a well-known herb worldwide and includes approximately 60 species of the Rheum genus. One of the representative plants is Rheum palmatum, which is prescribed as official rhubarb due to its pharmacological potential in the Korean and Chinese pharmacopoeia. In our bioactive screening, we found out that the EtOH extract of R. palmatum inhibited hepatic stellate cell (HSC) activation by transforming growth factor β1 (TGF-β1). Chemical investigation of the EtOH extract led to the isolation of chrysophanol 8-O-glucoside, which was determined by structural analysis using NMR spectroscopic techniques and electrospray ionization mass spectrometry (ESIMS). To elucidate the effects of chrysophanol 8-O-glucoside on HSC activation, activated LX-2 cells were treated for 48 h with chrysophanol 8-O-glucoside, and α-SMA and collagen, HSC activation markers, were measured by comparative quantitative real-time PCR (qPCR) and western blotting analysis. Chrysophanol 8-O-glucoside significantly inhibited the protein and mRNA expression of α-SMA and collagen compared with that in TGF-β1-treated LX-2 cells. Next, the expression of phosphorylated SMAD2 (p-SMAD2) and p-STAT3 was measured and the translocation of p-STAT3 to the nucleus was analyzed by western blotting analysis. The expression of p-SMAD2 and p-STAT3 showed that chrysophanol 8-O-glucoside strongly downregulated STAT3 phosphorylation by inhibiting the nuclear translocation of p-STAT3, which is an important mechanism in HSC activation. Moreover, chrysophanol 8-O-glucoside suppressed the expression of p-p38, not that of p-JNK or p-Erk, which can activate STAT3 phosphorylation and inhibit MMP2 expression, the downstream target of STAT3 signaling. These findings provided experimental evidence concerning the hepatoprotective effects of chrysophanol 8-O-glucoside against liver damage and revealed the molecular basis underlying its anti-fibrotic effects through the blocking of HSC activation.

A comprehensive review of natural products to fight liver fibrosis: Alkaloids, terpenoids, glycosides, coumarins and other compounds

The discovery of drugs to treat liver fibrosis has long been a challenge over the past decades due to its complicated pathogenesis. As a primary approach for drug development, natural products account for 30% of clinical drugs used for disease treatment. Therefore, natural products are increasingly important for their medicinal value in liver fibrosis therapy. In this part of the review, special focus is placed on the effect and mechanism of natural compounds, including alkaloids, terpenoids, glycosides, coumarins and others. A total of 36 kinds of natural compounds demonstrate significant antifibrotic effects in various liver fibrosis models in vivo and in hepatic stellate cells (HSCs) in vitro. Revealing the mechanism will provide further basis for clinical conversion, as well as accelerate drug discovery. The mechanism was further summarized with the finding of network regulation by several natural products, such as oxymatrine, paeoniflorin, ginsenoside Rg1 and taurine. Moreover, there are still improvements needed in investigating clinical efficacy, determining mechanisms, and combining applications, as well as semisynthesis and modification. Therefore, natural products area promising resource for agents that protect against liver fibrosis.

Wu-Mei-Wan ameliorates chronic colitis-associated intestinal fibrosis through inhibiting fibroblast activation

ETHNOPHARMACOLOGICAL RELEVANCE

Wu-Mei-Wan (WMW), a classic traditional Chinese herb medicine, is one of the most important formulations to treat digestive diseases from ancient times to the present. Previous study showed that WMW has satisfactory curative effects on experimental colitis, which motivating the application of WMW on colitis-associated complications.

AIM OF THE STUDY

Intestinal fibrosis is usually considered to be a common complication of inflammatory bowel disease (IBD), particularly Crohn's disease (CD). Currently, no effective preventive measures or medical therapies are available for that. This work was designed to evaluate the effect and related mechanism of WMW on chronic colitis-associated intestinal fibrosis mice model.

MATERIALS AND METHODS

The chronic colitis-associated intestinal fibrosis mice model was established by weekly intrarectal injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS). The mice survival rate, disease activity index (DAI), colon length and histological score were examined to assess the therapeutic effect of WMW. Masson's trichrome staining, hydroxyproline assay, immunohistochemical staining and western blot analysis were used to evaluate fibrosis level. Colon inflammation was determined by ELISA and immunofluorescence staining. Immunofluorescence staining was used to evaluate fibroblasts proliferation and epithelial to mesenchymal transition (EMT), and the expression of key molecules in fibrosis was analyzed by western blot.

RESULTS

Here we showed that WMW alleviates chronic colitis with improved survival rate, DAI, colon length and histological score. WMW inhibited the progression of intestinal fibrosis, decreased the expression of various fibrosis markers, such as α-SMA, collagen I, MMP-9 and fibronectin. In addition, WMW treatment reduced cytokines IL-6 and IFN-γ, and downregulated proinflammatory NF-κBp65 and STAT3 signaling pathways. Importantly, administration of WMW led to the inhibition of colon fibroblast proliferation and EMT, which are important mediators during fibrosis. Several key profibrotic pathways, including TGF-β/Smad and Wnt/β-catenin pathways, were downregulated by WMW treatment.

CONCLUSION

Our work demonstrated that WMW can prevent intestinal fibrosis and the mechanisms involved may be related to the inhibition of colon fibroblasts activation.

Ginsenosides: potential therapeutic source for fibrosis-associated human diseases

Tissue fibrosis is an eventual pathologic change of numerous chronic illnesses, which is characterized by resident fibroblasts differentiation into myofibroblasts during inflammation, coupled with excessive extracellular matrix deposition in tissues, ultimately leading to failure of normal organ function. Now, there are many mechanistic insights into the pathogenesis of tissue fibrosis, which facilitate the discovery of effective antifibrotic drugs. Moreover, many chronic diseases remain a significant clinical unmet need. For the past five years, many research works have undoubtedly addressed the functional dependency of ginsenosides in different types of fibrosis and the successful remission in various animal models treated with ginsenosides. Caveolin-1, interleukin, thrombospondin-1 (TSP-1), liver X receptors (LXRs), Nrf2, microRNA-27b, PPARδ-STAT3, liver kinase B1 (LKB1)-AMPK, and TGF-β1/Smads are potential therapy targeting using ginsenosides. Ginsenosides can play a targeting role and suppress chronic inflammatory response, collagen deposition, and epithelial-mesenchymal transition (EMT), as well as myofibroblast activation to attenuate fibrosis. In this report, our aim was to focus on the therapeutic prospects of ginsenosides in fibrosis-related human diseases making use of results acquired from various animal models. These findings should provide important therapeutic clues and strategies for the exploration of new drugs for fibrosis treatment.

Chemical profliling of Dingkun Dan by ultra High performance liquid chromatography Q exactive orbitrap high resolution mass spectrometry

Dingkun Dan (DKD) has been widely used for a variety of gynecological disease. However, the systematic analysis of the chemical constituents of DKD has not been well established because of the complexity of the formula and confidentiality. In this paper, liquid chromatography Q Exactive high resolution accurate mass spectrometry (UHPLC-QE-HRMS) with automated MetaboLynx analysis was established to characterize the chemical constituents of DKD. The analysis was performed on a Water Acquity UPLC® HSS T3 using a gradient elution system. Full scan ranged 100-1500 m/z in positive and negative ion mode combined with MS/MS fragmentation for top 5 ions was proposed for aiding the structural identification of the components. All of the peaks were tentatively characterized by not only comparing the retention time and MS data with those from reported literature and database, but also summarizing the fragmentation pathways and promoting to other ingredients identification. Additionally, the network pharmacology study had been used to analysis the identified ingredients and DKD's clinical diseases. In this work, a total of 121 components and isomers were characterized, including amino acids, phenolic acids, lactones, terpenoids, alkaloids, saponins, flavonoids, and other compounds. Network pharmacology analysis showed that identified compounds, such as ginsenosides and notoginsenosides, crocin I, echinacoside, rutin and verbascoside, could be responsible for the pharmacological activity of DKD by regulating the hormone with related metabolism pathways, estrogen signaling pathways and serotonergic synapse pathways. It could indicate that UHPLC-MS showed obvious superiority used to find the potential bioactive compounds of complicated TCM formula without the process of extraction and isolation.

Traditional Chinese medicine combined with hepatic targeted drug delivery systems: A new strategy for the treatment of liver diseases

Liver diseases are clinically common and present a substantial public health issue. Many of the currently available drugs for the treatment of liver diseases suffer from limitations that include low hepatic distribution, lack of target effects, poor in vivo stability and adverse effects on other organs. Consequently, conventional treatment of hepatic diseases is ineffective. TCM is commonly used in the treatment of liver diseases worldwide, particularly in China, and has advantages over conventional therapy. HTDDS can be designed to enhance clinical efficacy in the treatment of liver diseases. We have conducted an extensive review of 335 studies reported since 1964. These included about 166 references involving the treatment of liver diseases with TCM (covering active components of TCM, single TCM and Chinese medicine formulas), 169 reports on HTDDS and background studies on liver-related diseases. Here we review the long history of TCM in the treatment of liver diseases.We have also reviewed the status of studies on active components of TCM using nanotechnology-based targeted delivery systems to provide support for further research and development of TCM-based targeted preparations for the treatment of liver disease.

Ginsenoside Rb1 does not halt osteoporotic bone loss in ovariectomized rats

Osteoporosis (OP) is a systemic skeletal disorder, manifesting with a reduction in bone mass and deterioration of the microarchitecture. Mesenchymal stem cells (MSCs) have an innate ability to differentiate into several cell types, including osteoblasts (OB). Ginsenoside Rb1 (GRb1) is an ethanol extract from ginseng and contains a highly concentrated form of ginsenoside. GRb1 shows extensive beneficial health effects such as anti-oxidative and anti-inflammatory functions, modulating the immune system and inhibiting osteoclastogenesis. We hypothesized that GRb1 can promote MSC differentiation into OBs and inhibit bone loss. In the present study, we aimed to address two questions: (1) Will GRb1 have a positive effect on osteogenic differentiation of MSCs? and (2) Will GRb1 halt bone loss in ovariectomized (OVX) rats? We investigated the effects of GRb1 on viability and osteogenic differentiation of rat mesenchymal stem cells (rMSCs). Our results showed that GRb1 at concentrations of 10⁻⁸ M and 10⁻⁶ M can increase alkaline phosphatase activity, mineralization and the expression of osteogenic related proteins, such as osteopontin and osteoprotegerin, while incubating rMSCs with osteogenic induction medium and GRb1. Adding GRb1 into the medium can prevent rMSCs from Oxidative damage at the concentration of 25μM H₂O₂. Furthermore, 40 4-month-old rats were assigned to 5 groups(8 rats per group): the basal group, the sham group, the OVX group, the high dose of GRb1 group (6 mg/kg/day) and the low dose of GRb1 group (3 mg/kg/day). Rats recrived treatment 3days after surgery and last for 14 weeks. Examinations included serum analysis, mechanical testing, Masson-Goldner trichrome staining and bone histomorphometry analysis. The results showed that OVX can lead to dyslipidemia and excessive oxidative stress, whereas GRb1 cannot significantly halt dyslipidemia and excessive oxidative stress in OVX rats. In addition, the bone density of the lumbar vertebra and femur were decreased significantly in the OVX rats, and GRb1 could not inhibit bone loss. Bone histomorphometry analysis showed that the number and width of bone trabecula of the tibia were reduced in OVX rats, and GRb1 could not prevent their occurrence. A bone biomechanics assay showed that GRb1 cannot improve the ability of bone structure to resist fracture of the femur in OVX rats. The current study demonstrated that GRb1 has an obvious effect on osteogenic differentiation in rMSCs but no obvious effect on bone loss in OVX rats. These findings indicate GRb1 has a positive effect on rMSCs but does not have an effect on bone loss in OVX rats at the concentration we used.

Functional role of ginseng-derived compounds in cancer

Ginseng is a natural product best known for its curative properties in diverse physiological processes such as cancer, neurodegenerative disorders, hypertension, and maintenance of hemostasis in the immune system. In previous decades, there have been some promising studies into the pharmacology and chemistry of ginseng components and the relationship between their structure and function. The emerging use of modified ginseng and development of new compounds from ginseng for clinical studies have been topics of study for many researchers. The present review deals with the anticancer, anti-inflammatory, antioxidant, and chemopreventive effects, and recent advances in microRNA technology related to red ginseng. The review also summarizes the current knowledge on the effect of ginsenosides in the treatment of cancer.

Korean Red Ginseng mitigates spinal demyelination in a model of acute multiple sclerosis by downregulating p38 mitogen-activated protein kinase and nuclear factor-κB signaling pathways

Background

The potential therapeutic values of Korean Red Ginseng extract (KRGE) in autoimmune disorders of nervous system have not been fully investigated.

Methods

We used an acute experimental autoimmune encephalomyelitis animal model of multiple sclerosis and determined the effects and mechanism of KRGE on spinal myelination.

Results

Pretreatment with KRGE (100 mg/kg, orally) for 10 days before immunization with myelin basic protein (MBP)_68-82 peptide exerted a protective effect against demyelination in the spinal cord, with inhibited recruitment and activation of immune cells including microglia, decreased mRNA expression of detrimental inflammatory mediators (interleukin-6, interferon-γ, and cyclooxygenase-2), but increased mRNA expression of protective inflammatory mediators (insulin-like growth factor β1, transforming growth factor β, and vascular endothelial growth factor-1). These results were associated with significant downregulation of p38 mitogen-activated protein kinase and nuclear factor-κB signaling pathways in microglia/macrophages, T cells, and astrocytes.

Conclusion

Our findings suggest that KRGE alleviates spinal demyelination in acute experimental autoimmune encephalomyelitis through inhibiting the activation of the p38 mitogen-activated protein kinase/nuclear factor-κB signaling pathway. Therefore, KRGE might be used as a new therapeutic for autoimmune disorders such as multiple sclerosis, although further investigation is needed.

Ginsenoside Rb1 improves cardiac function and remodeling in heart failure

We investigated the effect of ginsenoside Rb1 on cardiac function and remodeling in heart failure (HF). Four weeks after HF induction, the rats were administrated with ginsenoside Rb1 (35 and 70 mg/kg) and losartan (4.5 mg/kg) for 8 weeks. Losartan was used as a positive control. Cardiac function was assessed by measuring hemodynamic parameters. Histological changes were analyzed by HE and Masson’s trichrome staining. Cardiac hypertrophy, fibrosis, mitochondrial membrane potential and glucose transporter type 4 (GLUT4) levels were evaluated. In the present study, high dose of (H−) ginsenoside Rb1 decreased heart rate, improved cardiac function and alleviated histological changes induced by HF. H-ginsenoside Rb1 attenuated cardiac hypertrophy and myocardial fibrosis by decreasing left ventricular (LV) weight/heart weight ratio and cardiomyocyte cross-sectional area and reducing the levels of atrial natriuretic factor (ANF), β-myosin heavy chain (β-MHC), periostin, collagen I, Angiotensin II (Ang II), Angiotensin converting enzyme (ACE) and Ang II type 1 (AT1) receptor. Moreover, H-ginsenoside Rb1 decreased mitochondrial membrane potential and enhanced the translocation of GLUT4 to plasma membrane. The TGF-β1/Smad and ERK signaling pathways were inhibited and the Akt pathway was activated. These findings suggest that ginsenoside Rb1 might restore cardiac/mitochondrial function, increase glucose uptake and protect against cardiac remodeling via the TGF-β1/Smad, ERK and Akt signaling pathways.

Ameliorative effects of Compound K and ginsenoside Rh1 on non-alcoholic fatty liver disease in rats

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease, which has no standard treatment available. Panax notoginseng saponines (PNS) have recently been reported to protect liver against hepatocyte injury induced by ethanol or high fat diet (HFD) in rats. Compound K and ginsenoside Rh1 are the main metabolites of PNS. In this study, we evaluated the effects of CK and Rh1 on NAFLD. Rats fed HFD showed significant elevations in liver function markers, lipids, glucose tolerance, and insulin resistance. Treatment with CK or Rh1 either alone or in combination dramatically ameliorated the liver function impairment induced by HFD. Histologically, CK and Rh1 significantly reversed HFD-induced hepatocyte injury and liver fibrosis. In vitro experiments demonstrated that treatment with CK or Rh1 alone or in combination markedly induced cell apoptosis, and inhibited cell proliferation and activation in HSC-T6 cells. Additionally, CK and Rh1, either alone or in combination, also repressed the expression of fibrotic factors TIMP-1, PC-I, and PC-III. Taken together, our results demonstrate that CK and Rh1 have positive effects on NAFLD via the anti-fibrotic and hepatoprotective activity.

Molecular signaling of ginsenosides Rb1, Rg1, and Rg3 and their mode of actions

Ginseng has gained its popularity as an adaptogen since ancient days because of its triterpenoid saponins, known as ginsenosides. These triterpenoid saponins are unique and classified as protopanaxatriol and protopanaxadiol saponins based on their glycosylation patterns. They play many protective roles in humans and are under intense research as various groups continue to study their efficacy at the molecular level in various disorders. Ginsenosides Rb1 and Rg1 are the most abundant ginsenosides present in ginseng roots, and they confer the pharmacological properties of the plant, whereas ginsenoside Rg3 is abundantly present in Korean Red Ginseng preparation, which is highly known for its anticancer effects. These ginsenosides have a unique mode of action in modulating various signaling cascades and networks in different tissues. Their effect depends on the bioavailability and the physiological status of the cell. Mostly they amplify the response by stimulating phosphotidylinositol-4,5-bisphosphate 3-kinase/protein kinase B pathway, caspase-3/caspase-9-mediated apoptotic pathway, adenosine monophosphate-activated protein kinase, and nuclear factor kappa-light-chain-enhancer of activated B cells signaling. Furthermore, they trigger receptors such as estrogen receptor, glucocorticoid receptor, and N-methyl-d-aspartate receptor. This review critically evaluates the signaling pathways attenuated by ginsenosides Rb1, Rg1, and Rg3 in various tissues with emphasis on cancer, diabetes, cardiovascular diseases, and neurodegenerative disorders.

Effect of ginseng extract on the TGF-β1 signaling pathway in CCl4-induced liver fibrosis in rats

Background

Liver diseases are major global health problems. Ginseng extract has antioxidant, immune-modulatory and anti-inflammatory activities. This study investigated the effect of ginseng extract on carbon tetrachloride (CCl4)-induced liver fibrosis in rats.

Methods

Male Wistar rats were divided into four groups: control group, ginseng group, CCl₄ group and CCl₄ + ginseng group. Liver injury was induced by the intraperitoneal (I.P) injection of 3 ml/kg CCl₄ (30% in olive oil) weekly for 8 weeks. The control group was I.P injected with olive oil. The expression of genes encoding transforming growth factor beta (TGF-β), type I TGF-β receptor (TβR-1), type II TGF-β receptor (TβR-II), mothers against decapentaplegic homolog 2 (Smad2), Smad3, Smad4, matrix metalloproteinase 2 (MMP2), MMP9, tissue inhibitor matrix metalloproteinase-1 (TIMP-1), Collagen 1a2 (Col1a2), Collagen 3a1 (Col3a1), interleukin-8 (IL-8) and interleukin -10 (IL-10) were measured by real-time PCR.

Results

Treatment with ginseng extract decreased hepatic fat deposition and lowered hepatic reticular fiber accumulation compared with the CCl₄ group. The CCl₄ group showed a significant increase in hepatotoxicity biomarkers and up-regulation of the expression of genes encoding TGF-β, TβR-I, TβR-II, MMP2, MMP9, Smad-2,-3, -4, and IL-8 compared with the control group. However, CCl₄ administration resulted in the significant down-regulation of IL-10 mRNA expression compared with the control group. Interestingly, ginseng extract supplementation completely reversed the biochemical markers of hepatotoxicity and the gene expression alterations induced by CCl₄.

Conclusion

ginseng extract had an anti‐fibrosis effect via the regulation of the TGF‐β1/Smad signaling pathway in the CCl₄‐induced liver fibrosis model. The major target was the inhibition of the expression of TGF‐β1, Smad2, and Smad3.

Ginseng for Liver Injury: Friend or Foe?

Panax sp., including Panax ginseng Meyer, Panax quiquifolius L., or Panax notoginseng (Burk.) FH Chen, have been used as functional foods or for traditional Chinese medicine for diabetes, inflammation, stress, aging, hepatic injury, and cancer. In recent decades, a number of both in vitro and in vivo experiments as well as human studies have been conducted to investigate the efficacy and safety of various types of ginseng samples and their components. Of these, the hepatoprotective and hepatotoxic effects of ginseng and their ginsenosides and polysaccharides are reviewed and summarized.

Effects of Complementary Combination Therapy of Korean Red Ginseng and Antiviral Agents in Chronic Hepatitis B

OBJECTIVES

Chronic hepatitis B management is commonly targeted at reducing viral replication. However, the currently available antiviral therapies are associated with some problems, including resistance and numerous adverse effects. Ginseng has been reported to be effective for treating viral infections such as influenza and human immunodeficiency virus. However, there are currently few studies on the effects of ginseng in chronic hepatitis B. Thus, this study investigated the effects of ginseng together with antiviral agents in chronic hepatitis B.

SUBJECTS AND METHODS

This was a prospective, single-blinded, randomized controlled trial, and single-center study. Thirty-eight patients were enrolled. The control group (n = 19) was administered antiviral agents alone. The experimental group (n = 19) was administered antiviral agents along with Korean Red Ginseng powder capsules (each dose is 1 gram (two capsules), a one-day dose is 3 grams). The baseline characteristics did not differ between the two groups. Differences in several non-invasive fibrosis serologic markers (type IV collagen, hyaluronic acid, transforming growth factor-β) and in the hepatitis B virus DNA levels were compared between the groups.

RESULTS

The non-invasive fibrosis serologic markers were further decreased in the experimental group, with significant differences after treatment observed for hyaluronic acid (p = 0.032) and transforming growth factor-β (p = 0.008), but not for type IV collagen (p = 0.174).

CONCLUSIONS

This study suggests the possibility of Korean Red Ginseng as a complementary therapy for chronic hepatitis B.

The Kampo medicine "Daikenchuto (TU-100)" prevents bacterial translocation and hepatic fibrosis in a rat model of biliary atresia

BACKGROUND

Biliary atresia is the most common cause of end-stage liver disease in children. It is known that bile duct ligation contributes to liver fibrosis via bacterial translocation (BT) and toll-like receptor 4 (TLR4) signaling of hepatic stellate cells (HSCs). We have reported previously that the traditional Japanese medicine, "Dai-kenchu-to (TU-100)," a form of "Kampo medicine" prevents BT in rats exposed to the stress of fasting. The aim of this study was to clarify the effect of TU-100 on a rat model of biliary atresia using bile duct ligation.

METHODS

Bile duct ligation and subsequent daily oral administration of TU-100 was performed in 6-week-old rats. The rats were killed at 3, 7, or 14 days after bile duct ligation to evaluate the liver injury, occurrence of BT, and hepatic fibrosis. As an in vitro experiment, we isolated fresh HSCs from the rats undergoing bile duct ligation. After cell attachment, TU-100 and its 3 component herbs (eg, processed ginger, ginseng radix, and Japanese pepper) were added, and the expressions of Alpha actin2 (acta2), Alpha-1 type I collagen (colIa1), and tissue inhibitor of metalloproteinase 1 (timp1) were analyzed.

RESULTS

In vivo experiments demonstrated that oral administration of TU-100 decreased liver injury and atrophy of intestinal mucosa BT, hepatic fibrosis, and hepatic expression of alpha smooth muscle actin (αSMA) and TLR4, compared with rats that underwent bile duct ligation only. In vitro experiments showed that administration of TU-100 or the component herbs inhibited the expressions of acta2, colIa1, and timp1 in the HSCs.

CONCLUSION

TU-100 prevented BT, activation of HSCs, and subsequent hepatic fibrosis. TU-100 may prevent progression of hepatic fibrosis in children with biliary atresia and improve prognosis.

Ginsenoside Rb1 attenuates angiotensin II-induced abdominal aortic aneurysm through inactivation of the JNK and p38 signaling pathways

BACKGROUND

Abdominal aortic aneurysm (AAA), a life-threatening vascular disease, accounts for approximately 10% of the morbidity in people over 65 years old. No satisfactory approach is available to treat AAA. Ginsenosides Rb1 and Rg1 are primary ingredients of Panax notoginseng for the treatment of cardiovascular diseases, but their impact on AAA is unknown.

METHODS AND RESULTS

An AAA model was established using an Ang II infusion in ApoE(-/-) mice. After continuous stimulation of Ang II for 28 days, suprarenal aortic aneurysms developed in 77% mice and 12% mice died suddenly due to AAA rupture. Administration of ginsenoside Rb1 (20 mg/kg/day), but not ginsenoside Rg1, significantly reduced the incidence and mortality of AAA. Ginsenoside Rb1 treatment dramatically suppressed Ang II-induced diameter enlargement, extracellular matrix degradation, matrix metalloproteinase (MMP) production, inflammatory cell infiltration, and vascular smooth muscle cell (VSMC) dysfunction. Mechanistic studies indicated that the protective effects of ginsenoside Rb1 were associated with the inactivation of JNK and p38 MAPK signaling pathways. A specific activator of JNK and p38, anisomycin, nearly abolished ginsenoside Rb1-driven suppression of MMP secretion by VSMCs.

CONCLUSIONS

Ginsenoside Rb1, as a potential anti-AAA agent, suppressed AAA through inhibiting the JNK and p38 signaling pathways.

Ginsenoside Rb1 relieves glucose fluctuation-induced oxidative stress and apoptosis in Schwann cells

Cultured Schwann cells were treated with 5.6 mM and 50 mM glucose alternating every 8 hours to simulate intermittent high glucose. The present study analyzed the neuroprotective effects of 1, 10 and 100 μM ginsenoside Rb1 on oxidative damage and apoptosis in Schwann cells induced by intermittent high glucose. Flow cytometry demonstrated that ginsenoside Rb1 reduced intermittent high glucose-mediated reactive oxygen species production. Enzyme linked immunosorbent assay showed that 8-hydroxy-2-deoxy guanosine levels in Schwann cells decreased following ginsenoside Rb1 treatment. Quantitative real-time reverse transcription-PCR and western blot assay results revealed that ginsenoside Rb1 inhibited intermittent high glucose-upregulated Bax expression, but antagonized intermittent high glucose-downregulated Bcl-2 expression in Schwann cells. These effects were most pronounced with 100 μM ginsenoside Rb1. These results indicate that ginsenoside Rb1 inhibits intermittent high glucose-induced oxidative stress and apoptosis in Schwann cells.

Protective mechanisms of medicinal plants targeting hepatic stellate cell activation and extracellular matrix deposition in liver fibrosis

During chronic liver injury, hepatic stellate cells (HSC) are activated and proliferate, which causes excessive extracellular matrix (ECM) deposition, leading to scar formation and fibrosis. Medicinal plants are gaining popularity as antifibrotic agents, and are often safe, cost-effective, and versatile. This review aims to describe the protective role and mechanisms of medicinal plants in the inhibition of HSC activation and ECM deposition during the pathogenesis of liver fibrosis. A systematic literature review on the anti-fibrotic mechanisms of hepatoprotective plants was performed in PubMed, which yielded articles about twelve relevant plants. Many of these plants act via disruption of the transforming growth factor beta 1 signaling pathway, possibly through reduction in oxidative stress. This reduction could explain the inhibition of HSC activation and reduction in ECM deposition. Medicinal plants could be a source of anti-liver fibrosis compounds.

Ginseng extract and ginsenoside Rb1 attenuate carbon tetrachloride-induced liver fibrosis in rats

Background

Ginsenosides, the major bioactive compounds in ginseng root, have been found to have antioxidant, immunomodulatory and anti-inflammatory activities. This study investigated the effects of ginsenosides on carbon tetrachloride (CCl₄)-induced hepatitis and liver fibrosis in rats.

Methods

Male Sprague–Dawley rats were randomly divided into four groups: control, CCl₄, CCl₄ + 0.5 g/kg Panax ginseng extract and CCl₄ + 0.05 g/kg ginsenoside Rb1 groups. The treated groups were orally given Panax ginseng extract or ginsenoside Rb1 two weeks before the induction of liver injury for successive 9 weeks. Liver injury was induced by intraperitoneally injected with 400 ml/l CCl₄ at a dose of 0.75 ml/kg body weight weekly for 7 weeks. The control group was intraperitoneally injected with olive oil.

Results

The pathological results showed that ginsenoside Rb1 decreased hepatic fat deposition (2.65 ± 0.82 vs 3.50 ± 0.75, p <0.05) and Panax ginseng extract lowered hepatic reticular fiber accumulation (1.05 ± 0.44 vs 1.60 ± 0.39, p <0.01) increased by CCl₄. Plasma alanine aminotransferase and aspartate aminotransferase activities were increased by CCl₄ (p <0.01)_, and aspartate aminotransferase activity was decreased by Panax ginseng extract at week 9 (p <0.05). Exposure to CCl₄ for 7 weeks, the levels of plasma and hepatic triglycerides (p <0.01), hepatic cholesterol (p <0.01), interleukin-1β (p <0.01), prostaglandin E₂ (p <0.05), soluble intercellular adhesion molecule-1 (p <0.05), hydroxyproline (p <0.05), matrix metalloproteinase-2 (p <0.05) and tissue inhibitor of metalloproteinase-1 (TIMP-1) (p <0.01) were elevated, however, hepatic interleukin-10 level was lowered (p <0.05). Both Panax ginseng extract and ginsenoside Rb1 decreased plasma and hepatic triglyceride, hepatic prostaglandin E₂, hydroxyproline and TIMP-1 levels, and Panax ginseng extract further inhibited interleukin-1β concentrations (p <0.05).

Conclusions

Panax ginseng extract and ginsenoside Rb1 attenuate plasma aminotransferase activities and liver inflammation to inhibit CCl₄-induced liver fibrosis through down-regulation of hepatic prostaglandin E₂ and TIMP-1.

Construction of an shRNA expression vector targeting the Crk gene: Potential role of Crk in liver fibrosis

AIM: To construct a short-hairpin RNA (shRNA) eukaryotic expression vector targeting the v-Crk avian sarcoma virus CT10 oncogene homolog gene (Crk) and to study the potential role of Crk in liver fibrosis.

METHODS: The shRNA oligonucleotide fragments were designed and synthesized based on the sequence of Crk mRNA. Double strands were then formed after annealing and inserted into the plko vector. Recombinant lentiviral vector was transfected into 293T cells to package lentivirus. LX-2 cells were then infected with the recombinant lentivirus and the function of Crk was studied after infection.

RESULTS: RT-PCR and Western bolt analyses indicated that after successful infection, both mRNA and protein expression was dramatically down-regulated, compared with the control group. Knockdown of Crk decreased the expression of collagen type 1 (Col1), α-smooth muscle actin (α-SMA) and the capacity of cell migration, but had no effect on cell proliferation.

CONCLUSION: We have successfully constructed an shRNA eukaryotic expression vector targeting the Crk gene. Knockdown of Crk can inhibit liver fibrosis possibly by suppressing the activation and migration of LX-2 cells.

TGF-β1 up-regulates the expression of PDGF-β receptor mRNA and induces a delayed PI3K-, AKT-, and p70(S6K) -dependent proliferative response in activated hepatic stellate cells

BACKGROUND

Transforming growth factor beta 1 (TGF-β1) is a pleiotropic cytokine that activates hepatic stellate cell (HSC) proliferation, but inhibits parenchymal cell proliferation. Therefore, we hypothesize that TGF-β1 regulates HSC proliferation and elucidated its molecular action.

METHODS

In order to elucidate the molecular mechanism whereby TGF-β1 up-regulates platelet derived growth factor beta (PDGF-β) receptor mRNA and induces a delayed proliferation of HSC, we used proliferation and apoptosis assays as well as RT-PCR, Western blot analysis, immunostaining, and flow cytometry in mouse and rat HSC.

RESULTS

We show that TGF-β1 markedly induces the proliferation of mouse HSC in culture with concomitant 2.1-fold (p < 0.001) stimulation in [(3) H]-thymidine incorporation into cellular DNA. This induction is maximal between 24 and 36 hours postcytokine exposure that is triggered by 7.6-fold (p < 0.001) up-regulation of PDGF-β receptor mRNA and associated increase in PDGF-β receptor protein after 48 hours. TGF-β1-dependent HSC proliferation is mimicked by H2 O2 that is inhibited by catalase, implying that TGF-β1 action is mediated via reactive oxygen species. HSC proliferation is blunted by PDGF-β receptor-neutralizing antibody as well as by specific inhibitors of PI3 kinase (PI3K), AKT, and p70(S6K) , indicating that the action of TGF-β1 involves the activation of PDGF-β receptor via the PI3K/AKT/p70(S6K) signaling pathway. TGF-β1 also induces a reorganization of actin and myosin filaments and cell morphology leading to the formation of palisades although their myosin and actin contents remained constant. These findings suggest that TGF-β1-mediated oxidative stress causes the transdifferentiation of HSC and primes them for extracellular matrix (ECM) deposition and scar contraction.

CONCLUSIONS

We conclude that liver injury up-regulates TGF-β1 that inhibits parenchymal cell proliferation, but stimulates HSC proliferation leading to the production of ECM and type I collagen resulting in fibrosis.

Current understanding on antihepatocarcinoma effects of xiao chai hu tang and its constituents

Xiao Chai Hu Tang (XCHT), a compound formula originally recorded in an ancient Chinese medical book Shanghanlun, has been used to treat chronic liver diseases for a long period of time in China. Although extensive studies have been demonstrated the efficacy of this formula to treat chronic hepatitis, hepatic fibrosis, and hepatocarcinoma, how it works against these diseases still awaits full understanding. Here, we firstly present an overview arranging from the entire formula to mechanism studies of single herb in XCHT and their active components, from a new perspective of "separation study," and we tried our best to both detailedly and systematically organize the antihepatocarcinoma effects of it, hoping that the review will facilitate the strive on elucidating how XCHT elicits its antihepatocarcinoma role.

Red ginseng extract protects against carbon tetrachloride-induced liver fibrosis

Korean red ginseng, the processed root of Panax ginseng Meyer, has been frequently used for various therapeutic purposes in oriental medicine. The present study investigated the possible effect of Korean red ginseng extract (RGE) for the treatment of liver fibrosis in mice injected with carbon tetrachloride (CCl4) for 4 wk. Liver injuries were assessed by blood biochemistry and histopathology in mice treated with CCl4 alone or CCl4+ RGE (30, 100, and 300 mg/kg). Concomitant treatment with RGE and CCl4 (three times/wk for 4 wk) effectively inhibited liver fibrosis as evidenced by decreases in plasma alanine and aspartate aminotransferases, as well as by the percentages of degenerative regions, numbers of degenerative hepatocytes, and collagen accumulation in hepatic parenchyma. Treatment with CCl4 for 4 wk increased mRNA levels of transforming growth factor β1 and plasminogen activator inhibitor 1 in fibrogenic liver, whereas RGE (30, 100, and 300 mg/kg) significantly blocked the induction of fibrogenic genes by CCl4. Similarly, RGE also prevented transforming growth factor β1-mediated induction of fibrogenic genes in human hepatic stellate cell lines. More importantly, RGE markedly reduced the number of α-smooth muscle actin-positive cells in liver tissue. This study implies that RGE efficaciously protects against the liver fibrosis induced by chronic CCl4 treatment, and may therefore have potential to treat liver disease.

Implication of the stereoisomers of ginsenoside derivatives in the antiproliferative effect of HSC-T6 cells

Two ginsenoside derivatives (9, 10) along with 10 known ginsenosides (1-8, 11, and 12) were isolated from BST204, which is a crude ginseng extract fermented by enzyme and acid hydrolysis. The two ginsenosides were determined as 12β,20(S),25-trihydroxydammara-3-O-β-D-glucopyranoside (9) and 12β,20(R),25-trihydroxydammara-3-O-β-D-glucopyranoside (10). Compounds 1-12 were categorized into stereoisomeric pairs differentiated by R- or S-configuration at C-20, the number or position of sugar residues at C-3 or C-6, and the type of derivative at C-21. Their structure-activity relationship was evaluated by the cell viability assay using HSC-T6 cells. Results showed that 20(S) (3 > 4, 7 > 8, and 9 > 10), a 2-hydroxy-2-methylbutyl moiety at C-21 (3, 7 > 9), and the number of sugar residues at C-3 (3 > 7) significantly affected the antiproliferative activity on HSC-T6 cells. The inhibition of the cell proliferation of compound 3 was assessed by annexin-V/PI staining analysis using flow cytometry.

Ginseng and Its Active Components Ginsenosides Inhibit Adipogenesis in 3T3-L1 Cells by Regulating MMP-2 and MMP-9

The growth and development of adipose tissue are believed to require adipogenesis, angiogenesis, and extracellular matrix remodeling. As our previous study revealed that ginseng reduces adipose tissue mass in part by decreasing matrix metalloproteinase (MMP) activity in obese mice, we hypothesized that adipogenesis can be inhibited by ginseng and its active components ginsenosides (GSs). Treatment of 3T3-L1 adipocytes with Korean red ginseng extract (GE) inhibited lipid accumulation and the expression of adipocyte-specific genes (PPARγ, C/EBPα, aP2, and leptin). GE decreased both the mRNA levels and activity of MMP-2 and MMP-9 in 3T3-L1 cells. These effects were further inhibited by total GSs (TGSs) and individual GSs. TGSs and individual GSs also significantly decreased MMP-2 and MMP-9 reporter gene activities in the presence of phorbol 12-myristate 13-acetate (PMA), the MMP inducer. Among the GSs, Rb1 most effectively inhibited MMP activity. In addition, PMA treatment attenuated the inhibitory actions of GE and GSs on adipogenesis. Moreover, GE and GSs reduced the expression of NF-κB and AP-1, the transcription factors of MMP-2 and MMP-9. These results demonstrate that ginseng, in particular GSs, effectively inhibits adipogenesis and that this process may be mediated in part through the suppression of MMP-2 and MMP-9. Thus, ginseng and GSs likely have therapeutic potential for controlling adipogenesis.

Pharmacological effects of ginseng on liver functions and diseases: a minireview

Ginseng, an ancient and famous medicinal herb in the Orient, has been used as a valuable tonic and for the treatment of various diseases including hepatic disorders. Ginseng saponins, commonly known as ginsenosides, are principal constituents and have believed to be responsible for multiple ginseng health benefits. There are more 40 ginsenosides isolated from ginseng. To date, treatment options for common liver diseases such as cirrhosis, fatty liver, and chronic hepatitis remain problematic. In this regard, ginseng extracts and individual ginsenosides have shown a wide array of beneficial role in the regulation of regular liver functions and the treatment of liver disorders of acute/chronic hepatotoxicity, hepatitis, hepatic fibrosis/cirrhosis, hepatocellular carcinoma, and so on in various pathways and mechanisms. In this paper, we first outline the pharmacological effects of ginseng and ginsenosides on the liver functions.

Pharmacodynamics of ginsenosides: antioxidant activities, activation of Nrf2, and potential synergistic effects of combinations

Ginseng has long been used in Asian countries for more than 2000 years. Currently, in the "Western World or Western Medicines", many reports have indicated that they have used herbal medicines, and ginseng is one of the most popular herbs. Several recent reports have indicated that the antioxidant/antioxidative stress activities of ginseng play a role in the benefits of ginseng; however, the precise mechanism is lacking. The antioxidant response element (ARE) is a critical regulatory element for the expression of many antioxidant enzymes and phase II/III drug metabolizing/transporter genes, mediated by the transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2). The aim of this study was to examine the potential activation and synergism of Nrf2-ARE-mediated transcriptional activity between three common ginsenosides present in ginseng, ginsenoside Rb1 (Rb1), ginsenoside Rg1 (Rg1), and ginsenoside 20(S)-protopanaxatriol (20S). We tested whether these ginsenosides and their combinations could induce Nrf2-ARE activities in HepG2-C8 cells with stably transfected ARE luciferase reporter gene. Cell proliferation, antioxidant and ARE activities, Western blotting of Nrf2 protein, and qPCR of mRNA of Nrf2 were conducted for Rb1, Rg1, and 20S as well as the combinations of 20S with Rb1 or Rg1. To determine the combination effects, the combination index (CI) was calculated. Rb1 and Rg1 are relatively nontoxic to the cells, while 20S at 50 μM or above significantly inhibited the cell proliferation. Rb1, Rg1, or 20S induced total antioxidant activity and ARE activity in a concentration-dependent manner. Furthermore, combinations of 20S with either Rb1 or Rg1 induced total antioxidant and ARE activity synergistically. The induction of Nrf2 protein and mRNA was also found to be synergistic with the combination treatments. In summary, in this study, we show that ginsenosides Rb1, Rg1, and 20S possess antioxidant activity, transcriptionally activating ARE as well as the potential of synergistic activities. The Nrf2-ARE-mediated antioxidant pathway could play a role for the overall antioxidative stress activities, which could be important for ginseng's health beneficial effects such as cancer chemopreventive activities.

The role of bioactive compounds on the promotion of neurite outgrowth

Neurite loss is one of the cardinal features of neuronal injury. Apart from neuroprotection, reorganization of the lost neuronal network in the injured brain is necessary for the restoration of normal physiological functions. Neuritogenic activity of endogenous molecules in the brain such as nerve growth factor is well documented and supported by scientific studies which show innumerable compounds having neurite outgrowth activity from natural sources. Since the damaged brain lacks the reconstructive capacity, more efforts in research are focused on the identification of compounds that promote the reformation of neuronal networks. An abundancy of natural resources along with the corresponding activity profiles have shown promising results in the field of neuroscience. Recently, importance has also been placed on understanding neurite formation by natural products in relation to neuronal injury. Arrays of natural herbal products having plentiful active constituents have been found to enhance neurite outgrowth. They act synergistically with neurotrophic factors to promote neuritogenesis in the diseased brain. Therefore use of natural products for neuroregeneration provides new insights in drug development for treating neuronal injury. In this study, various compounds from natural sources with potential neurite outgrowth activity are reviewed in experimental models.