The antidiabetic effect of ginsenoside Rb2 via activation of AMPK

Ginsenosides for the treatment of insulin resistance and diabetes: Therapeutic perspectives and mechanistic insights

Diabetes mellitus (DM) is a systemic disorder of energy metabolism characterized by a sustained elevation of blood glucose in conjunction with impaired insulin action in multiple peripheral tissues (i.e., insulin resistance). Although extensive research has been conducted to identify therapeutic targets for the treatment of DM, its global prevalence and associated mortailty rates are still increasing, possibly because of challenges related to long-term adherence, limited efficacy, and undesirable side effects of currently available medications, implying an urgent need to develop effective and safe pharmacotherapies for DM. Phytochemicals have recently drawn attention as novel pharmacotherapies for DM based on their clinical relevance, therapeutic efficacy, and safety. Ginsenosides, pharmacologically active ingredients primarily found in ginseng, have long been used as adjuvants to traditional medications in Asian countries and have been reported to exert promising therapeutic efficacy in various metabolic diseases, including hyperglycemia and diabetes. This review summarizes the current pharmacological effects of ginsenosides and their mechanistic insights for the treatment of insulin resistance and DM, providing comprehensive perspectives for the development of novel strategies to treat DM and related metabolic complications.

Effect of anti-skin disorders of ginsenosides- A Systematic Review

Ginsenosides are bioactive components of Panax ginseng with many functions such as anti-aging, anti-oxidation, anti-inflammatory, anti-fatigue, and anti-tumor. Ginsenosides are categorized into dammarane, oleanene, and ocotillol type tricyclic triterpenoids based on the aglycon structure. Based on the sugar moiety linked to C-3, C-20, and C-6, C-20, dammarane type was divided into protopanaxadiol (PPD) and protopanaxatriol (PPT). The effects of ginsenosides on skin disorders are noteworthy. They play anti-aging roles by enhancing immune function, resisting melanin formation, inhibiting oxidation, and elevating the concentration of collagen and hyaluronic acid. Thus, ginsenosides have previously been widely used to resist skin diseases and aging. This review details the role of ginsenosides in the anti-skin aging process from mechanisms and experimental research.

Phytochemical Profiles and Biological Studies of Selected Botanical Dietary Supplements Used in the United States

Based on their current wide bioavailability, botanical dietary supplements have become an important component of the United States healthcare system, although most of these products have limited scientific evidence for their use. The most recent American Botanical Council Market Report estimated for 2020 a 17.3% increase in sales of these products when compared to 2019, for a total sales volume of $11,261 billion. The use of botanical dietary supplements products in the United States is guided by the Dietary Supplement Health and Education Act (DSHEA) from 1994, enacted by the U.S. Congress with the aim of providing more information to consumers and to facilitate access to a larger number of botanical dietary supplements available on the market than previously. Botanical dietary supplements may be formulated for and use only using crude plant samples (e.g., plant parts such as the bark, leaves, or roots) that can be processed by grinding into a dried powder. Plant parts can also be extracted with hot water to form an "herbal tea." Other preparations of botanical dietary supplements include capsules, essential oils, gummies, powders, tablets, and tinctures. Overall, botanical dietary supplements contain bioactive secondary metabolites with diverse chemotypes that typically are found at low concentration levels. These bioactive constituents usually occur in combination with inactive molecules that may induce synergy and potentiation of the effects observed when botanical dietary supplements are taken in their different forms. Most of the botanical dietary supplements available on the U.S. market have been used previously as herbal remedies or as part of traditional medicine systems from around the world. Their prior use in these systems also provides a certain level of assurance in regard to lower toxicity levels. This chapter will focus on the importance and diversity of the chemical features of bioactive secondary metabolites found in botanical dietary supplements that are responsible for their applications. Many of the active principles of botanical dietary substances are phenolics and isoprenoids, but glycosides and some alkaloids are also present. Biological studies on the active constituents of selected botanical dietary supplements will be discussed. Thus, the present chapter should be of interest for both members of the natural products scientific community, who may be performing development studies of the products available, as well as for healthcare professionals who are directly involved in the analysis of botanical interactions and evaluation of the suitability of botanical dietary supplements for human consumption.

An Overview of the Potential of Medicinal Plants Used in the Development of Nutraceuticals for the Management of Diabetes Mellitus: Proposed Biological Mechanisms

Diabetes mellitus (DM) is a chronic metabolic disorder in which the pancreas does not produce enough insulin or the body cannot effectively use it. The prevalence of diabetes is increasing steadily, making it a global public health problem. Several serious complications are associated with this disease. There are a number of different classes of antidiabetic medications. Interestingly, traditional medicine can also be used for the development of novel classes of hypoglycemic therapeutics. This article summarizes an update of the potential of various important medicinal plants used in the development of nutraceuticals for the management of diabetes mellitus, and a proposal of their biological mechanisms.

Immunomodulatory Effect of Ginsenoside Rb2 Against Cyclophosphamide-Induced Immunosuppression in Mice

Ginsenoside Rb2 (Rb2), a fundamental saponin produced and isolated from ginseng (Panax ginseng C.A. Meyer), has a wide range of biological actions. The objective of this investigation was to see if ginsenoside Rb2 has any immunomodulatory properties against cyclophosphamide (CTX)-induced immunosuppression. For the positive control group, levamisole hydrochloride (LD) was used. We discovered that intraperitoneal injection of Rb2 (5, 10, 20 mg/kg) could relieve CTX-induced immunosuppression by enhanced immune organ index, reduced the pathological characteristics of immunosuppression, promoted natural killer (NK) cells viability, improved cell-mediated immune response, boosted the IFN-γ (Interferon-gamma), TNF-α (Tumor necrosis factor-alpha), IL-2 (Interleukin-2), and IgG (Immunoglobulin G), as well as macrophage activity like carbon clearance and phagocytic index. Rb2 significantly elevated the mRNA expression of IL-4 (Interleukin-4), SYK (Tyrosine-protein kinase-SYK), IL-2, TNF-α, and IL-6 (Interleukin-6) in the spleen of CTX-injected animals. Molecular docking results showed that Rb2 had excellent binding properties with IL-4, SYK, IL-2, TNF, and IL-6, indicating the target protein might be strongly correlated with the immunomodulatory effect of Rb2. Taken together, ginsenoside Rb2 can improve the immune function that is declined in CTX-induced immunosuppressed mice, the efficacy maybe due to the regulation of related cytokine and mRNA expression.

Ginsenoside compound K ameliorates palmitate-induced atrophy in C2C12 myotubes via promyogenic effects and AMPK/autophagy-mediated suppression of endoplasmic reticulum stress

Background

Compound K (CK) is among the protopanaxadiol (PPD)-type ginsenoside group, which produces multiple pharmacological effects. Herein, we examined the effects of CK on muscle atrophy under hyperlipidemic conditions along with its pro-myogenic effects. Further, the molecular pathways underlying the effects of CK on skeletal muscle have been justified.

Methods

C2C12 myotubes were treated with palmitate and CK. C2C12 myoblasts were differentiated using CK for 4-5 days. For the in vivo experiments, CK was administered to mice fed on a high-fat diet for 8 weeks. The protein expression levels were analyzed using western blotting analysis. Target protein suppression was performed using small interfering (si) RNA transfection. Histological examination was performed using Jenner-Giemsa and H&E staining techniques.

Results

CK treatment attenuated ER stress markers, such as eIF2α phosphorylation and CHOP expression and impaired myotube formation in palmitate-treated C2C12 myotubes and skeletal muscle of mice fed on HFD. CK treatment augmented AMPK along with autophagy markers in skeletal muscle cells in vitro and in vivo experiments. AMPK siRNA or 3-MA, an autophagy inhibitor, abrogated the impacts of CK in C2C12 myotubes. CK treatment augmented p38 and Akt phosphorylation, leading to an enhancement of C2C12 myogenesis. However, AMPK siRNA abolished the effects of CK in C2C12 myoblasts.

Conclusion

These findings denote that CK prevents lipid-induced skeletal muscle apoptosis via AMPK/autophagy-mediated attenuation of ER stress and induction of myoblast differentiation. Therefore, we may suggest the use of CK as a potential therapeutic approach for treating muscle-wasting conditions associated with obesity.

Using Network Pharmacology to Explore the Mechanism of Panax notoginseng in the Treatment of Myocardial Fibrosis

OBJECTIVE

The mechanism of Panax notoginseng in treating myocardial fibrosis (MF) was investigated using network pharmacology.

METHODS

Effective ingredients and potential targets of Panax notoginseng were screened in relevant databases to construct a compound-target network. Targets of MF were then screened to select common targets and construct a protein-protein interaction network. This was followed by Gene Ontology and pathway enrichment analyses. Molecular docking then verified the results of network analysis.

RESULTS

A total of 14 effective ingredients and 119 potential targets for MF were predicted. Quercetin, beta-sitosterol, and gossypetin were speculated to be the main active ingredients. The mechanism of action may be related to AGE-RAGE, proteoglycans, and IL-17 signaling pathways. Five key targets (IL6, ALB, AKT1, TNF, and VEGFA) may be involved in the treatment of MF using Panax notoginseng.

CONCLUSIONS

This study embodies the complex network relationship of multicomponents, multitargets, and multipathways of Panax notoginseng in treating MF and provides a novel method for further research on this herb's mechanism.

Hypoglycemic and Hypolipidemic Effects of Malonyl Ginsenosides from American Ginseng (Panax quinquefolius L.) on Type 2 Diabetic Mice

American ginseng (Panax quinquefolius L.) is popularly consumed as traditional herbal medicine and health food for the treatment of type 2 diabetes mellitus (T2DM). Malonyl ginsenosides (MGR) are the main natural ginsenosides in American ginseng. However, whether the malonyl ginsenosides in P. quinquefolius (PQ-MGR) possess antidiabetic effects has not been explored yet. In this study, the antidiabetic effects and the underlying mechanism of PQ-MGR in high-fat diet/streptozotocin (HFD/STZ)-induced T2DM mice were investigated. The chemical composition was analyzed by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Our results showed that 14 malonyl ginsenosides were identified in the PQ-MGR. Among them, the content of m-Rb₁ represented about 77.4% of the total malonyl ginsenosides. After a 5-week experiment, the PQ-MGR significantly reduced the fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), nonesterified fatty acid (NEFA), alanine transaminase (ALT), and aspartate transaminase (AST) levels and improved glucose tolerance and insulin resistance. Furthermore, Western blot analysis demonstrated that the protein expressions of p-PI3K, p-AKT, p-AMPK, p-ACC, PPAR_γ, and GLUT4 in the liver and skeletal muscle were significantly upregulated after PQ-MGR treatment. In contrast, the protein expressions of p-IRS1 and p-JNK were significantly downregulated. Our results revealed that PQ-MGR could ameliorate glucose and lipid metabolism and insulin resistance in T2DM via regulation of the insulin receptor substrate-1/phosphoinositide3-kinase/protein-kinase B (IRS1/PI3K/Akt) and AMP-activated protein kinase/acetyl-CoA carboxylase (AMPK/ACC) pathways. These findings suggest that PQ-MGR may be used as an antidiabetic candidate drug for T2DM treatment.

Chemical Synthesis of Saponins

Saponins are a large family of amphiphilic glycosides of steroids and triterpenes found in plants and some marine organisms. By expressing a large diversity of structures on both sugar chains and aglycones, saponins exhibit a wide range of biological and pharmacological properties and serve as major active principles in folk medicines, especially in traditional Chinese medicines. Isolation of saponins from natural sources is usually a formidable task due to the microheterogeneity of saponins in Nature. Chemical synthesis can provide access to large amounts of natural saponins as well as congeners for understanding their structure-activity relationships and mechanisms of action. This article presents a comprehensive account on chemical synthesis of saponins. First highlighted are general considerations on saponin synthesis, including preparation of aglycones and carbohydrate building blocks, assembly strategies, and protecting-group strategies. Next described is the state of the art in the synthesis of each type of saponins, with an emphasis on those representative saponins having sophisticated structures and potent biological activities.

Novel Triterpenoids from Cassia fistula Stem Bark Depreciates STZ-Induced Detrimental Changes in IRS-1/Akt-Mediated Insulin Signaling Mechanisms in Type-1 Diabetic Rats

Here, we identified the mechanisms of action of antidiabetic activity of novel compounds isolated from Cassia fistula stem bark in STZ-diabetic animals. Novel triterpenoid compounds (C1, C2 and C3) were treated to STZ-administered diabetic animals at a concentration of 20mg/kg body weight orally for 60 days to assess their effects on plasma glucose, plasma insulin/C-peptide, serum lipid markers and the enzymes of carbohydrate metabolism, glucose oxidation and insulin signaling molecules. Oral administration of novel triterpenoid compounds to STZ-diabetic animals significantly decreased (p < 0.05) the plasma glucose concentration on the 7th, 15th, 30th, 45th and 60th daysin a duration-dependent manner (p < 0.05). Plasma insulin (p < 0.0001)/C-peptide (p < 0.0006), tissue glycogen (p < 0.0034), glycogen phosphorylase (p < 0.005), glucose 6-phosphatase (p < 0.0001) and lipid markers were significantly increased (p < 0.0001) in diabetic rats, whereas glucokinase (p < 0.0047), glycogen synthase (p < 0.003), glucose oxidation (p < 0.001), GLUT4 mRNA (p < 0.0463), GLUT4 protein (p < 0.0475) and the insulin-signaling molecules IR mRNA (p < 0.0195), IR protein (p < 0.0001), IRS-1 mRNA (p < 0.0478), p-IRS-1Tyr612 (p < 0.0185), Akt mRNA (p < 0.0394), p-AktSer473 (p < 0.0162), GLUT4 mRNA (p < 0.0463) and GLUT4 (p < 0.0475) were decreased in the gastrocnemius muscle. In silico analysis of C1-C3 with IRK and PPAR-γ protein coincided with in vivo findings. C1-C3 possessed promising antidiabetic activity by regulating insulin signaling mechanisms and carbohydrate metabolic enzymes.

Ginsenoside Rb2: A review of pharmacokinetics and pharmacological effects

Ginsenoside Rb2 is an active protopanaxadiol-type saponin, widely existing in the stem and leave of ginseng. Rb2 has recently been the focus of studies for pharmaceutical properties. This paper provides an overview of the preclinical and clinical pharmacokinetics for Rb2, which exhibit poor absorption, rapid tissue distribution and slow excretion through urine. Pharmacological studies indicate a beneficial role of Rb2 in the prevention and treatment of diabetes, obesity, tumor, photoaging, virus infection and cardiovascular problems. The underlying mechanism is involved in an inhibition of oxidative stress, ROS generation, inflammation and apoptosis via regulation of various cellular signaling pathways and molecules, including AKT/SHP, MAPK, EGFR/SOX2, TGF-β1/Smad, SIRT1, GPR120/AMPK/HO-1 and NF-κB. This work would provide a new insight into the understanding and application of Rb2. However, its therapeutic effects have not been clinically evaluated. Further studies should be aimed at the clinical treatment of Rb2.

The effects of ginseng on the metabolic syndrome: An updated review

Metabolic syndrome is a group of risk factors including high blood glucose, dyslipidemia, high blood pressure, and high body weight. It can increase the risk of diabetes and cardiovascular disorders, which are the important reasons for death around the world. Nowadays, there are numerous demands for herbal medicine because of less harmful effects and more useful effects in comparison with chemical options. Ginseng is one of the most famous herbs used as a drug for a variety of disorders in humans. The antihyperlipidemia, antihypertension, antihyperglycemic, and anti-obesity effects of ginseng and its active constituents such as ginsenosides have been shown in different studies. In this review article, the different in vitro, in vivo, and human studies concerning the effects of ginseng and its active constituents in metabolic syndrome have been summarized. According to these studies, ginseng can control metabolic syndrome and related diseases.

Pharmacokinetic and metabolism study of ginsenoside Rb2 in rat by liquid chromatography combined with electrospray ionization tandem mass spectrometry

In this study, a simple and rapid ultra-fast liquid chromatography tandem mass spectrometry method was established and validated to determine ginsenosides Rb2 in rat plasma. Acetonitrile-mediated protein precipitant was applied to the sample preparation. Chromatographic separation was carried out on an Acquity UPLC HSS T3 column (100 × 2.1 mm, 1.8 μm). The analytes were monitored using multiple reactions monitoring mode with precursor-to-product ion transitions at m/z 1077.4-945.3 and m/z 799.8 → 637.8 for ginsenoside Rb2 and internal standard, respectively. The mobile phase was composed of 0.1% formic acid aqueous solution and acetonitrile. The assay showed excellent linearity over the concentration range of 2-1,000 ng/ml, with correlation coefficient >0.995. The method was further validated for selectivity, precision, accuracy, recovery, and stability according to the US Food and Drug Administration guidelines. The validated method was successfully applied to pharmacokinetic and bioavailability studies of ginsenoside Rb2 in rat plasma. Based on the pharmacokinetic results, ginsenoside Rb2 showed slow clearance and low oral bioavailability (0.15%). In addition, the metabolites of ginsenoside Rb2 in rat urine and feces were characterized according to their accurate masses and fragment ions. The proposed metabolic pathway was deglycosylation.

Paving the Road Toward Exploiting the Therapeutic Effects of Ginsenosides: An Emphasis on Autophagy and Endoplasmic Reticulum Stress

Programmed cell death processes such as apoptosis and autophagy strongly contribute to the onset and progression of cancer. Along with these lines, modulation of cell death mechanisms to combat cancer cells and elimination of resistance to apoptosis is of great interest. It appears that modulation of autophagy and endoplasmic reticulum (ER) stress with specific agents would be beneficial in the treatment of several disorders. Interestingly, it has been suggested that herbal natural products may be suitable candidates for the modulation of these processes due to few side effects and significant therapeutic potential. Ginsenosides are derivatives of ginseng and exert modulatory effects on the molecular mechanisms associated with autophagy and ER stress. Ginsenosides act as smart phytochemicals that confer their effects by up-regulating ATG proteins and converting LC3-I to -II, which results in maturation of autophagosomes. Not only do ginsenosides promote autophagy but they also possess protective and therapeutic properties due to their capacity to modulate ER stress and up- and down-regulate and/or dephosphorylate UPR transducers such as IRE1, PERK, and ATF6. Thus, it would appear that ginsenosides are promising agents to potentially restore tissue malfunction and possibly eliminate cancer.

Network Pharmacology-Based Identification of the Mechanisms of Shen-Qi Compound Formula in Treating Diabetes Mellitus

Aim

The purpose of this research is to identify the mechanisms of Shen-Qi compound formula (SQC), a traditional Chinese medicine (TCM), for treating diabetes mellitus (DM) using system pharmacology.

Methods

The active components and therapeutic targets were identified, and these targets were analyzed using gene ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and protein-protein interaction (PPI) analysis. Finally, an integrated pathway was constructed to show the mechanisms of SQC.

Results

A total of 282 active components and 195 targets were identified through a database search. The component-target network was constructed, and the key components were screened out according to their degree. Through the GO, PPI, and KEGG analyses, the mechanism network of SQC treating DM was constructed.

Conclusions

This study shows that the mechanisms of SQC treating DM are related to various pathways and targets. This study provides a good foundation and basis for further in-depth verification and clinical application.

Ginsenoside Rb2 Ameliorates LPS-Induced Inflammation and ER Stress in HUVECs and THP-1 Cells via the AMPK-Mediated Pathway

Inflammation and endoplasmic reticulum (ER) stress have been documented to contribute to the development of atherosclerosis. Ginsenoside Rb2 has been reported to exhibit antidiabetic effects. However, the effects of Rb2 on atherosclerotic responses such as inflammation and ER stress in endothelial cells and monocytes remain unclear. In this study, the expression of inflammation and ER stress markers was determined using a Western blotting method. Concentrations of tumor necrosis factor alpha (TNF[Formula: see text]) and monocyte chemoattractant protein-1 (MCP-1) in culture media were assessed by enzyme-linked immunosorbent assay (ELISA) and apoptosis was evaluated by a cell viability assay and a caspase-3 activity measurement kit. We found that exposure of HUVECs and THP-1 monocytes to Rb2 attenuated inflammation and ER stress, resulting in amelioration of apoptosis and THP-1 cell adhesion to HUVECs under lipopolysaccharide (LPS) condition. Increased AMPK phosphorylation and heme oxygenase (HO)-1 expression, including GPR120 expression were observed in Rb2-treated HUVECs and THP-1 monocytes. Downregulation of both, AMPK phosphorylation and HO-1expression rescued these observed changes. Furthermore, GPR120 siRNA mitigated Rb2-induced AMPK phosphorylation. These results suggest that Rb2 inhibits LPS-mediated apoptosis and THP-1 cell adhesion to HUVECs by GPR120/AMPK/HO-1-associated attenuating inflammation and ER stress. Therefore, Rb2 can be used as a potential therapeutic molecule for treatment of atherosclerosis.

Steamed Panax notoginseng Attenuates Anemia in Mice With Blood Deficiency Syndrome via Regulating Hematopoietic Factors and JAK-STAT Pathway

Panax notoginseng (Burk.) F. H. Chen is a medicinal herb used to treat blood disorders since ancient times, of which the steamed form exhibits the anti-anemia effect and acts with a “blood-tonifying” function according to traditional use. The present study aimed to investigate the anti-anemia effect and underlying mechanism of steamed P. notoginseng (SPN) on mice with blood deficiency syndrome induced by chemotherapy. Blood deficiency syndrome was induced in mice by cyclophosphamide and acetylphenylhydrazine. A number of peripheral blood cells and organs (liver, kidney, and spleen) coefficients were measured. The mRNA expression of hematopoietic function-related cytokines in the bone marrow of mice was detected by RT-qPCR. The janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway was screened based on our previous analysis by network pharmacology. The expression of related proteins and cell cycle factors predicted in the pathway was determined by Western blot and RT-qPCR. SPN could significantly increase the numbers of peripheral blood cells and reverse the enlargement of spleen in a dose-dependent manner. The quantities of related hematopoietic factors in bone marrow were also increased significantly after SPN administration. SPN was involved in the cell cycle reaction and activation of immune cells through the JAK-STAT pathway, which could promote the hematopoiesis.

The Molecular Mechanism of Ginsenoside Analogs Activating TMEM16A

The calcium-activated chloride channel TMEM16A is involved in many physiological processes, and insufficient function of TMEM16A may lead to the occurrence of various diseases. Therefore, TMEM16A activators are supposed to be potentially useful for treatment of TMEM16A downregulation-inducing diseases. However, the TMEM16A activators are relatively rare, and the underlying activation mechanism of them is unclear. In the previous work, we have proved that ginsenoside Rb1 is a TMEM16A activator. In this work, we explored the activation mechanism of ginsenoside analogs on TMEM16A through analyzing the interactions between six ginsenoside analogs and TMEM16A. We identified GRg2 and GRf can directly activate TMEM16A by screening five novel ginsenosids analogs (GRb2, GRf, GRg2, GRh2, and NGR1). Isolated guinea pig ileum assay showed both GRg2 and GRf increased the amplitude and frequency of ileum contractions. We explored the molecular mechanisms of ginsenosides activating TMEM16A by combining molecular simulation with electrophysiological experiments. We proposed a TMEM16A activation process model based on the results, in which A697 on TM7 and L746 on TM8 bind to the isobutenyl of ginsenosides through hydrophobic interaction to fix the spatial location of ginsenosides. N650 on TM6 and E705 on TM7 bind to ginsenosides through electrostatic interaction, which causes the inner half of α-helix 6 to form physical contact with ginsenosides and leads to the pore opening. It should be emphasized that TMEM16A can be activated by ginsenosides only when both the above two conditions are satisfied. This is the first, to our knowledge, report of TMEM16A opening process activated by small-molecule activators. The mechanism of ginsenosides activating TMEM16A will provide important clues for TMEM16A gating mechanism and for new TMEM16A activators screening.

Ginsenoside compound-Mc1 attenuates oxidative stress and apoptosis in cardiomyocytes through an AMP-activated protein kinase-dependent mechanism

Background

Ginsenoside compound-Mc1 (Mc1) is a member of the deglycosylated ginsenosides obtained from ginseng extract. Although several ginsenosides have a cardioprotective effect, this has not been demonstrated in ginsenoside Mc1.

Methods

We treated H9c2 cells with hydrogen peroxide (H₂O₂) and ginsenoside Mc1 to evaluate the antioxidant effects of Mc1. The levels of antioxidant molecules, catalase, and superoxide dismutase 2 (SOD2) were measured, and cell viability was determined using the Bcl2-associated X protein (Bax):B-cell lymphoma-extra large ratio, a cytotoxicity assay, and flow cytometry. We generated mice with high-fat diet (HFD)–induced obesity using ginsenoside Mc1 and assessed their heart tissues to evaluate the antioxidant effect and the fibrosis-reducing capability of ginsenoside Mc1.

Results

Ginsenoside Mc1 significantly increased the level of phosphorylated AMP-activated protein kinase (AMPK) in the H9c2 cells. The expression levels of catalase and SOD2 increased significantly after treatment with ginsenoside Mc1, resulting in a decrease in the production of H₂O₂-mediated reactive oxygen species. Treatment with ginsenoside Mc1 also significantly reduced the H₂O₂-mediated elevation of the Bax:Bcl2 ratio and the number of DNA-damaged cells, which was significantly attenuated by treatment with an AMPK inhibitor. Consistent with the in vitro data, ginsenoside Mc1 upregulated the levels of catalase and SOD2 and decreased the Bax:B-cell lymphoma-extra large ratio and caspase-3 activity in the heart tissues of HFD-induced obese mice, resulting in reduced collagen deposition.

Conclusion

Ginsenoside Mc1 decreases oxidative stress and increases cell viability in H9c2 cells and the heart tissue isolated from HFD-fed mice via an AMPK-dependent mechanism, suggesting its potential as a novel therapeutic agent for oxidative stress–related cardiac diseases.

Autophagy and its regulation by ginseng components

Autophagy is the sequential process whereby cell components are degraded, which can occur due to nutrient deprivation. Its regulation has an essential role in many diseases, functioning in both cell survival and cell death. Autophagy starts when mTORC1 is inhibited, resulting in the activation of several complexes to form a cargo that fuses with a lysosome, where it undergoes degradation. In this review, we describe a plant extract that is well known in Korea, namely Korean ginseng extract; we studied how its derivatives and metabolites can regulate autophagy and thus mediate the pathogenesis of certain diseases.

Mentha pulegium Aqueous Extract Exhibits Antidiabetic and Hepatoprotective Effects in Streptozotocin-Induced Diabetic Rats

Objective:

The aim of this work was to evaluate the antihyperglycemic activity of aerial parts aqueous extract (A.P.A.E) of Mentha pulegium (M. pulegium) on blood glucose levels in normal and streptozotocin(STZ)-induced diabetic rat. The glucose tolerance was evaluated in normal rats. Moreover, the histological sections and morphometric analysis at the liver and pancreas have been carried out in this investigation both in normal and STZ-diabetic rats.

Methods:

The effect of A.P.A.E of M. pulegium (20 mg/kg) on blood glucose levels was investigated in normal and diabetic rats (n=6). Histopathological changes in liver and pancreas were examined under phase contrast microscope and a preliminary screening for various bioactive constituents was realized according to standard methods.

Key Findings:

Both single and repeated oral administration of A.P.A.E (20 mg/kg) caused a significant reduction in blood glucose levels in STZ-diabetic rats (p<0.0001). The morphometric analysis and histological sections realized in pancreas and liver have showed the beneficial effect of the A.P.A.E in cellular population. According to oral glucose tolerance test (OGTT), the aqueous extract has revealed an improvement of glucose tolerance in normal rat. Furthermore, the preliminary phytochemical screening of A.P.A.E of M. pulegium has demonstrated the presence of various metabolite compounds including polyphenols, flavonoids, terpenoids tannins, cyanidins, sesquiterpenes, and glycosides.

Conclusion:

We conclude that the A.P.A.E of M. pulegium (20 mg/kg) exhibits a potent antihyperglycemic activity in STZ diabetic rats.

Ginsenoside Rb1 and Rb2 upregulate Akt/mTOR signaling-mediated muscular hypertrophy and myoblast differentiation

Background

As a process of aging, skeletal muscle mass and function gradually decrease. It is reported that ginsenoside Rb1 and Rb2 play a role as AMP-activated protein kinase activator, resulting in regulating glucose homeostasis, and Rb1 reduces oxidative stress in aged skeletal muscles through activating the phosphatidylinositol 3-kinase/Akt/Nrf2 pathway. We examined the effects of Rb1 and Rb2 on differentiation of the muscle stem cells and myotube formation.

Methods

C2C12 myoblasts treated with Rb1 and/or Rb2 were differentiated and induced to myotube formation, followed by immunoblotting for myogenic marker proteins, such as myosin heavy chain, MyoD, and myogenin, or immunostaining for myosin heavy chain or immunoprecipitation analysis for heterodimerization of MyoD/E-proteins.

Results

Rb1 and Rb2 enhanced myoblast differentiation through accelerating MyoD/E-protein heterodimerization and increased myotube hypertrophy, accompanied by activation of Akt/mammalian target of rapamycin signaling. In addition, Rb1 and Rb2 induced the MyoD-mediated transdifferentiation of the rhabdomyosarcoma cells into myoblasts. Furthermore, co-treatment with Rb1 and Rb2 had synergistically enhanced myoblast differentiation through Akt activation.

Conclusion

Rb1 and Rb2 upregulate myotube growth and myogenic differentiation through activating Akt/mammalian target of rapamycin signaling and inducing myogenic conversion of fibroblasts. Thus, our first finding indicates that Rb1 and Rb2 have strong potential as a helpful remedy to prevent and treat muscle atrophy, such as age-related muscular dystrophy.

Ginseng for the treatment of diabetes and diabetes-related cardiovascular complications: a discussion of the evidence 1

Diabetes mellitus (DM) is a chronic metabolic disorder associated with elevated blood glucose levels due either to insufficient insulin production (type 1 DM) or to insulin resistance (type 2 DM). The incidence of DM around the world continues to rise dramatically with more than 400 million cases reported today. Among the most serious consequences of chronic DM are cardiovascular complications that can have deleterious effects. Although numerous treatment options are available, including both pharmacological and nonpharmacological, there is substantial emerging interest in the use of traditional medicines for the treatment of this condition and its complications. Among these is ginseng, a medicinal herb that belongs to the genus Panax and has been used for thousands of years as a medicinal agent especially in Asian cultures. There is emerging evidence from both animal and clinical studies that ginseng, ginseng constituents including ginsenosides, and ginseng-containing formulations can produce beneficial effects in terms of normalization of blood glucose levels and attenuation of cardiovascular complications through a multiplicity of mechanisms. Although more research is required, ginseng may offer a useful therapy for the treatment of diabetes as well as its complications.

Ginsenosides: the need to move forward from bench to clinical trials

Panax ginseng, known as Koran ginseng, one of the most commonly used traditional plants, has been demonstrated to show a wide range of pharmacological applications. Ginsenosides are the major active ingredients found in ginseng and are responsible for the biological and pharmacological activities, such as antioxidation, antiinflammation, vasorelaxation, and anticancer actions. Existing studies have mostly focused on identifying and purifying single ginsenosides and investigating pharmacological activities and molecular mechanisms in cells and animal models. However, ginsenoside studies based on clinical trials have been very limited. Therefore, this review aimed to discuss the currently available clinical trials on ginsenosides and provide insights and future directions for developing ginsenosides as efficacious and safe drugs for human disease.

Effect of Liuweibuqi capsules on CD4+CD25+Foxp3+ regulatory T cells, helper T cells and lung function in patients with stable chronic obstructive pulmonary disease complicated with lung Qi deficiency

Background

Chronic obstructive pulmonary disease (COPD) is predicted to become the fifth leading cause of disability and the third leading cause of death around the world by 2020. Though it is potentially treatable and preventable, evidence of brain structural alterations in COPD remains sparse and conflicting. We aim to investigate the effect of Liuweibuqi capsules on CD4⁺CD25⁺ Forkhead box protein 3⁺ (Foxp3⁺) regulatory T cells (Tregs), helper T cells (Th) and lung function in patients with stable COPD complicated with lung Qi deficiency.

Methods

COPD patients with lung Qi deficiency [458] were assigned into non-smoking COPD (NS-COPD), non-smoking control (NS-control), smoking COPD (S-COPD) and smoking control (S-control) groups, and healthy volunteers [245] into the non-smoking healthy (NSH) and smoking healthy (SH) groups. Levels of inflammatory cytokines were detected by Enzyme-linked immunoassay (ELISA). Contents of inflammatory cells, inflammatory marker, and CD4⁺CD25⁺Fox3⁺Tregs were measured by flow cytometry. FEV1/FVC (%) and FEV1 (%) were detected by pulmonary function test apparatus. Correlation between FEV1 (%) and Th1, Th2, Th17, Th1/Th2 or CD4⁺CD25⁺Fox3⁺Tregs was analyzed by Spearman rank correlation test. The related factors affecting treatment efficacy was assessed by logistic analysis.

Results

COPD patients and smoking people showed higher level of INF-γ, IL-4, IL-17, Th1, Th2, Th17 and Th1/Th2 but lower level of CD4⁺CD25⁺Fox3⁺Tregs. Liuweibuqi capsules could decrease level of inflammatory cells, cytokines, and markers (especially Th17 and IL-17), and increase level of CD4⁺CD25⁺Fox3⁺Tregs. FEV1 (%) negatively correlated with Th1, Th2, Th17 and Th1/Th2 but positively correlated with CD4⁺CD25⁺Fox3⁺Tregs, and smoking may strengthen their correlation, but Liuweibuqi capsules may weaker their correlation. Levels of inflammatory cytokines, cells, marker, CD4⁺CD25⁺Fox3⁺Tregs, FEV1/FVC (%), FEV1 (%), smoking and Liuweibuqi capsules are factors affecting efficacy.

Conclusions

Taken together, our data support the notion that smoking is an important factor to induce and aggravate COPD. Liuweibuqi capsules could stimulate proliferation of CD4⁺CD25⁺Fox3⁺Tregs and decrease Th17 expression to improve the lung function in stable COPD patients with lung Qi deficiency, and it had obvious efficacy for smoking COPD patients.

Gold-catalyzed glycosylation in the synthesis of complex carbohydrate-containing natural products

Gold(i)- and gold(iii)-catalyzed glycosylation reactions and their application in the synthesis of natural glycoconjugates are reviewed.

Molecular determinants of PPARγ partial agonism and related in silico/in vivo studies of natural saponins as potential type 2 diabetes modulators

The metabolic syndrome, which includes hypertension, type 2 diabetes (T2D) and obesity, has reached an epidemic-like scale. Saponins and sapogenins are considered as valuable natural products for ameliorating this pathology, possibly through the nuclear receptor PPARγ activation. The aims of this study were: to look for in vivo antidiabetic effects of a purified saponins' mixture (PSM) from Astragalus corniculatus Bieb; to reveal by in silico methods the molecular determinants of PPARγ partial agonism, and to investigate the potential PPARγ participation in the PSM effects. In the in vivo experiments spontaneously hypertensive rats (SHRs) with induced T2D were treated with PSM or pioglitazone as a referent PPARγ full agonist, and pathology-relevant biochemical markers were analysed. The results provided details on the PSM modulation of the glucose homeostasis and its potential mechanism. The in silico studies focused on analysis of the protein-ligand interactions in crystal structures of human PPARγ-partial agonist complexes, pharmacophore modelling and molecular docking. They outlined key pharmacophoric features, typical for the PPARγ partial agonists, which were used for pharmacophore-based docking of the main PSM sapogenin. The in silico studies, strongly suggest possible involvement of PPARγ-mediated mechanisms in the in vivo antidiabetic and antioxidant effects of PSM from A. corniculatus.

Protopanaxadiol and Protopanaxatriol-Type Saponins Ameliorate Glucose and Lipid Metabolism in Type 2 Diabetes Mellitus in High-Fat Diet/Streptozocin-Induced Mice

Ginsenoside is a major active component of ginseng, which exhibits various pharmacological properties such as hepatoprotection, tumor suppression and diabetes resistance. In this study, the anti-diabetic effects of protopanaxadiol (PPD) and protopanaxatriol (PPT)-type saponins were explored and compared in high-fat diet/streptozocin-induced type 2 diabetes mellitus (T2DM) mice. Our results showed that low or high dose (50 mg/kg bodyweight or 150 mg/kg bodyweight) PPD and PPT significantly reduced fasting blood glucose, improved glucose tolerance and insulin resistance in T2DM mice. PPD and PPT also regulated serum lipid-related markers such as reduced total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol in T2DM mice. In addition, PPD and PPT dramatically ameliorated the inflammatory responses by suppressing the secretion of pro-inflammatory cytokines like tumor necrosis factor-alpha and interleukin-6 in serum level and gene expression in liver level, and improved the antioxidant capacity by increasing the superoxide dismutase and decreasing malondialdehyde levels in the serum of T2DM mice. Moreover, the anti-diabetic effect of PPD and PPT appeared to be partially mediated by the suppression of hepatic metabolism genes expression such as peroxisome proliferator-activated receptor gamma coactivator 1-alpha, phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase, as well as facilitating lipid metabolism genes expression such as microsomal TG transfer protein in the liver tissues of T2DM mice. Taken together, our results indicated that PPD and PPT might potentially act as natural anti-diabetic compounds to be used for preventing and treating the T2DM and its complications in the future.

Ginsenoside Rb2 inhibits osteoclast differentiation through nuclear factor-kappaB and signal transducer and activator of transcription protein 3 signaling pathway

Ginsenoside-Rb2 (Rb2) is a 20(S)-protopanaxadiol glycoside extracted from ginseng possessing various bioactivities which has drawn considerable interest regarding the area of bone metabolism. However, the effect of Rb2 on osteoclast differentiation remains unknown. In this study, we aimed to investigate the potential role of Rb2 in regulating osteoclast differentiation and the underlying molecular mechanisms. Osteoclast differentiation was induced by receptor activator nuclear factor-kappaB (NF-κB) ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) in mouse RAW 264.7 cells. The results showed that Rb2 dose-dependently inhibited the formation of the tartrate resistant acid phosphatase (TRAP)-positive multinucleated cells and TRAP expression. Furthermore, Rb2 promoted osteoprotegerin expression and bone resorption. The expression of osteoclast marker genes including nuclear factor of activated T cells c1 (NFATc1), c-Fos, OSCAR, and cathepsin K were also markedly inhibited by Rb2 treatment. Moreover, Rb2 significantly inhibited the RANKL-induced NF-κB activation. In addition, Rb2 also markedly suppressed the activation of signal transducer and activator of transcription protein 3 (STAT3) signaling pathway. Interestingly, the knockdown of STAT3 significantly strengthened the inhibitory effect of Rb2 on osteoclast differentiation. Taken together, our study suggests that Rb2 inhibits osteoclast differentiation associated with blocking NF-κB and STAT3 signaling pathways.

Ginsenoside Rb2 Alleviates Hepatic Lipid Accumulation by Restoring Autophagy via Induction of Sirt1 and Activation of AMPK

Although Panax ginseng is a famous traditional Chinese medicine and has been widely used to treat a variety of metabolic diseases including hyperglycemia, hyperlipidemia, and hepatosteatosis, the effective mediators and molecular mechanisms remain largely unknown. In this study we found that ginsenoside Rb2, one of the major ginsenosides in Panax ginseng, was able to prevent hepatic lipid accumulation through autophagy induction both in vivo and in vitro. Treatment of male db/db mice with Rb2 significantly improved glucose tolerance, decreased hepatic lipid accumulation, and restored hepatic autophagy. In vitro, Rb2 (50 µmol/L) obviously increased autophagic flux in HepG2 cells and primary mouse hepatocytes, and consequently reduced the lipid accumulation induced by oleic acid in combination with high glucose. Western blotting analysis showed that Rb2 partly reversed the high fatty acid in combination with high glucose (OA)-induced repression of autophagic pathways including AMP-activated protein kinase (AMPK) and silent information regulator 1 (sirt1). Furthermore, pharmacological inhibition of the sirt1 or AMPK pathways attenuated these beneficial effects of Rb2 on hepatic autophagy and lipid accumulation. Taken together, these results suggested that Rb2 alleviated hepatic lipid accumulation by restoring autophagy via the induction of sirt1 and activation of AMPK, and resulted in improved nonalcoholic fatty liver disease (NAFLD) and glucose tolerance.

Ginsenoside Rb2 enhances the anti-inflammatory effect of ω-3 fatty acid in LPS-stimulated RAW264.7 macrophages by upregulating GPR120 expression

Recent studies confirm that chronic low-grade inflammation is closely associated with metabolic syndromes, and anti-inflammatory therapy is a potential approach for treating cardiovascular diseases and type 2 diabetes. Accumulating evidence suggests that GPR120 activation is a feasible solution to ameliorating chronic inflammation and improving glucose metabolism. In this study we investigated whether ginsenoside Rb2 (Rb2), which exhibited regulatory activities in glucose and lipid metabolism, affected GPR120 expression in lipopolysaccharide (LPS)-activated mouse macrophage RAW264.7 cells, and examined the contribution of GPR120 activation to reducing the LPS-induced inflammatory response. LPS (100 ng/mL) activated the macrophages, resulting in dramatic increases in TNF-α, IL-6, IL-1β and NO production. Treatment with a ω-3 fatty acid α-linolenic acid (ALA, 50 μmol/L) produced moderate reduction in LPS-stimulated inflammatory cytokines and NO production (TNF-α and IL-6 were decreased by 46% and 42%, respectively). Pre-incubation with Rb2 (1 or 10 μmol/L) for 12 h before ALA treatment dramatically amplified the inhibitory effects of ALA (TNF-α and IL-6 were decreased by 74% and 86%, respectively). Compared to the treatment with ALA alone, pre-incubation with Rb2 resulted in a more prominent reduction in LPS-stimulated expression of iNOS and COX-2 and LPS-stimulated IKK/NF-κB phosphorylation and MAPK pathway activation. Rb2 (0.1-100 μmol/L) dose- and time-dependently increased both mRNA and protein expression of GPR120 in RAW264.7 cells, but treatment with Rb2 alone did not exert anti-inflammatory effect in LPS-activated RAW264.7 cells. In RAW264.7 cells transfected with GPR120 shRNA, the ameliorating effects of Rb2 on LPS-induced inflammation were abolished. In conclusion, Rb2 exerts anti-inflammatory effect in LPS-stimulated mouse macrophage RAW264.7 cells in vitro by increasing GPR120 expression and subsequently enhancing ω-3 fatty acid-induced GPR120 activation.

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.

Screening of saponins and sapogenins from Medicago species as potential PPARγ agonists and X-ray structure of the complex PPARγ/caulophyllogenin

A series of saponins and sapogenins from Medicago species were tested for their ability to bind and activate the nuclear receptor PPARγ by SPR experiments and transactivation assay, respectively. The SPR analysis proved to be a very powerful and fast technique for screening a large number of compounds for their affinity to PPARγ and selecting the better candidates for further studies. Based on the obtained results, the sapogenin caulophyllogenin was proved to be a partial agonist towards PPARγ and the X-ray structure of its complex with PPARγ was also solved, in order to investigate the binding mode in the ligand binding domain of the nuclear receptor. This is the first known crystal structure of a sapogenin directly interacting with PPARγ. Another compound of the series, the echinocistic acid, showed antagonist activity towards PPARγ, a property that could be useful to inhibit the adipocyte differentiation which is a typical adverse effect of PPARγ agonists. This study confirms the interest on saponins and sapogenins as a valuable natural resource exploitable in the medical and food industry for ameliorating the metabolic syndrome.

Chinese herbal medicines as a source of molecules with anti-enterovirus 71 activity

Enterovirus 71 (EV71) is one of the causative agents of hand, foot, and mouth disease (HFMD), which sometimes leads to severe neurological disease and death in the Asia-Pacific region. In Chinese medicine, HFMD is caused mainly by an accumulation of damp-heat and toxicity in the body. No effective drugs are currently available for the treatment and prevention of EV71 infection. This review summarizes the potential Chinese herbal extracts and isolated compounds with antiviral activity against EV71 and their clinical applications, especially those categorized as heat-clearing and detoxifying.

The aglycone of ginsenoside Rg3 enables glucagon-like peptide-1 secretion in enteroendocrine cells and alleviates hyperglycemia in type 2 diabetic mice

Ginsenosides can be classified on the basis of the skeleton of their aglycones. Here, we hypothesized that the sugar moieties attached to the dammarane backbone enable binding of the ginsenosides to the sweet taste receptor, eliciting glucagon-like peptide-1 (GLP-1) secretion in the enteroendocrine L cells. Using the human enteroendocrine NCI-H716 cells, we demonstrated that 15 ginsenosides stimulate GLP-1 secretion according to the position of their sugar moieties. Through a pharmacological approach and RNA interference technique to inhibit the cellular signal cascade and using the Gαgust^−/− mice, we elucidated that GLP-1 secreting effect of Rg3 mediated by the sweet taste receptor mediated the signaling pathway. Rg3, a ginsenoside metabolite that transformed the structure through a steaming process, showed the strongest GLP-1 secreting effects in NCI-H716 cells and also showed an anti-hyperglycemic effect on a type 2 diabetic mouse model through increased plasma GLP-1 and plasma insulin levels during an oral glucose tolerance test. Our study reveals a novel mechanism where the sugar moieties of ginsenosides Rg3 stimulates GLP-1 secretion in enteroendocrine L cells through a sweet taste receptor-mediated signal transduction pathway and thus has an anti-hyperglycemic effect on the type 2 diabetic mouse model.

Medicinal Plants Qua Glucagon-Like Peptide-1 Secretagogue via Intestinal Nutrient Sensors

Glucagon-like peptide-1 (GLP-1) participates in glucose homeostasis and feeding behavior. Because GLP-1 is rapidly inactivated by the enzymatic cleavage of dipeptidyl peptidase-4 (DPP4) long-acting GLP-1 analogues, for example, exenatide and DPP4 inhibitors, for example, liraglutide, have been developed as therapeutics for type 2 diabetes mellitus (T2DM). However, the inefficient clinical performance and the incidence of side effects reported on the existing therapeutics for T2DM have led to the development of a novel therapeutic strategy to stimulate endogenous GLP-1 secretion from enteroendocrine L cells. Since the GLP-1 secretion of enteroendocrine L cells depends on the luminal nutrient constituents, the intestinal nutrient sensors involved in GLP-1 secretion have been investigated. In particular, nutrient sensors for tastants, cannabinoids, and bile acids are able to recognize the nonnutritional chemical compounds, which are abundant in medicinal plants. These GLP-1 secretagogues derived from medicinal plants are easy to find in our surroundings, and their effectiveness has been demonstrated through traditional remedies. The finding of GLP-1 secretagogues is directly linked to understanding of the role of intestinal nutrient sensors and their recognizable nutrients. Concurrently, this study demonstrates the possibility of developing novel therapeutics for metabolic disorders such as T2DM and obesity using nutrients that are readily accessible in our surroundings.

Chemical synthesis of saponins

Saponins are a large family of amphiphilic glycosides of steroids and triterpenes found in plants and some marine organisms. By expressing a large diversity of structures on both sugar chains and aglycones, saponins exhibit a wide range of biological and pharmacological properties and serve as major active principles in folk medicines, especially in traditional Chinese medicines. Isolation of saponins from natural sources is usually a formidable task due to the microheterogeneity of saponins in Nature. Chemical synthesis can provide access to large amounts of natural saponins as well as congeners for understanding their structure-activity relationships and mechanisms of action. This article presents a comprehensive account on chemical synthesis of saponins. First highlighted are general considerations on saponin synthesis, including preparation of aglycones and carbohydrate building blocks, assembly strategies, and protecting-group strategies. Next described is the state of the art in the synthesis of each type of saponins, with an emphasis on those representative saponins having sophisticated structures and potent biological activities.

Suppressive properties of ginsenoside Rb2, a protopanaxadiol-type ginseng saponin, on reactive oxygen species and matrix metalloproteinase-2 in UV-B-irradiated human dermal keratinocytes

Ginsenosides, also known as ginseng saponins, are the principal bioactive ingredients of ginseng, which are responsible for its diverse pharmacological activities. The present work aimed to assess skin anti-photoaging properties of ginsenoside Rb2 (Rb2), one of the predominant protopanaxadiol-type ginsenosides, in human epidermal keratinocyte HaCaT cells under UV-B irradiation. When the cultured keratinocytes were subjected to Rb2 prior to UV-B irradiation, Rb2 displayed suppressive activities on UV-B-induced reactive oxygen species elevation and matrix metalloproteinase-2 expression and secretion. However, Rb2 at the used concentrations was unable to modulate cellular survivals in the UV-B-irradiated keratinocytes. In brief, Rb2 possesses a protective role against the photoaging of human keratinocyte cells under UV-B irradiation.

Saponins: Anti-diabetic principles from medicinal plants - A review

Diabetes mellitus (DM) represents a global health problem. It is the most common of the endocrine disorders and is characterized by chronic hyperglycemia due to relative or absolute lack of insulin secretion or insulin actions. According to the World Health Organization projections, the diabetes population is likely to increase to 300 million or more by the year 2025. Current synthetic agents and insulin used effectively for the treatment of diabetes are scarce especially in rural areas, expensive and have prominent adverse effects. Complementary and alternative approaches to diabetes management such as isolation of phytochemicals with anti-hyperglycemic activities from medicinal plants is therefore imperative. Saponins are phytochemical with structural diversity and biological activities. This paper reviews saponins and various plants from which they were isolated as well as properties that make them ideal for antidiabetic remedy.

Efficacy and Safety of Panax notoginseng Saponin Therapy for Acute Intracerebral Hemorrhage, Meta-Analysis, and Mini Review of Potential Mechanisms of Action

Intracranial/intracerebral hemorrhage (ICH) is a leading cause of death and disability in people with traumatic brain injury (TBI) and stroke. No proven drug is available for ICH. Panax notoginseng (total saponin extraction, PNS) is one of the most valuable herb medicines for stroke and cerebralvascular disorders in China. We searched for randomized controlled clinical trials (RCTs) involving PNS injection to treat cerebral hemorrhage for meta-analysis from various databases including the Chinese Stroke Trials Register, the trials register of the Cochrane Complementary Medicine Field, the Cochrane Central Register of Controlled Trials, MEDLINE, Chinese BioMedical disk, and China Doctorate/Master Dissertations Databases. The quality of the eligible trials was assessed by Jadad’s scale. Twenty (20) of the 24 identified randomized controlled trials matched the inclusive criteria including 984 ICH patients with PNS injection and 907 ICH patients with current treatment (CT). Compared to the CT groups, PNS-treated patients showed better outcomes in the effectiveness rate (ER), neurological deficit score, intracranial hematoma volume, intracerebral edema volume, Barthel index, the number of patients died, and incidence of adverse events. Conclusion: PNS injection is superior to CT for acute ICH. A review of the literature shows that PNS may exert multiple protective mechanisms against ICH-induced brain damage including hemostasis, anti-coagulation, anti-thromboembolism, cerebral vasodilation, invigorated blood dynamics, anti-inflammation, antioxidation, and anti-hyperglycemic effects. Since vitamin C and other brain cell activators (BCA) that are not considered common practice were also used as parts of the CT in several trials, potential PNS and BCA interactions could exist that may have made the effect of PNS therapy less or more impressive than by PNS therapy alone. Future PNS trials with and without the inclusion of such controversial BCAs as part of the CT could clarify the situation. As PNS has a long clinical track record in Asia, it could potentially become a therapy option to treat ICH in the US and Europe. Further clinical trials with better experimental design could determine the long-term effects of PNS treatment for TBI and stroke.

A review on the medicinal potential of Panax ginseng saponins in diabetes mellitus

This review article summarizes the anti-diabetic effects and mechanisms ofPanax ginsengsaponins and its active specific ginsenosides.