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.

12,23-Dione dammarane triterpenes from Gynostemma longipes and their muscle cell proliferation activities via activation of the AMPK pathway

The aging population is growing rapidly around the world and there is also an increase in sarcopenia, which is characterized by decreased muscle mass, strength and function in the elderly population. AMP-activated protein kinase (AMPK) is an essential sensor and regulator of glucose, lipid and energy metabolism throughout the body. Previous studies have shown that AMPK pathway activation by regular exercise and appropriate dietary control have beneficial effects on skeletal muscle. In the process of searching for new AMPK activators from medicinal plants, we isolated and characterized eight new 12,23-dione dammarane triterpenoids (1-3 and 5-9), as well as one known gypentonoside A from Gynostemma longipes. When all isolates were tested for their AMPK activation activities, seven compounds (1 and 3-8) were significantly activated AMPK phosphorylation in mouse C2C12 skeletal muscle cell lines. Since G. longipes contained a significant amount of active compound 1 (over 2.08% per dried raw plant), it suggested the potential of this plant to be developed as a functional food or botanical drug that enhances muscle proliferation by activating AMPK signaling pathways.

Protective effect of ginsenoside Rg3 on lung injury in diabetic rats

Ginsenoside has been used to treat diabetes, while ginsenoside Rg3 is the main active ingredient component of ginseng and is used to study its effects on lung tissue damage in diabetic rats. In this paper, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry were applied to detect the proliferation and apoptosis of BEAS-2B cells treated with different concentrations of Rg3. The inflammatory response and pathological change in the lung tissue of diabetic rats treated with Rg3 were evaluated by enzyme-linked immunosorbent assay, quantative real-time polymerase chain reaction, and hematoxylin and eosin staining immunohistochemistry. Meanwhile, PI3K and MAPK signaling pathway proteins in lung tissue were determined by Western blot analysis. The results showed that ginsenoside Rg3 had no significant influence on the proliferation and apoptosis of BEAS-2B cells. Ginsenoside Rg3 can inhibit inflammatory response and promote the activation of PI3K and MAPK signaling pathways to prevent damages of lung tissues induced by hyperglycemia. The protective effect provided by ginsenoside Rg3 indicates that ginsenoside Rg3 is a potential drug for the treatment of diabetes.

UPLC-QTOF/MS-Based Metabolomics Applied for the Quality Evaluation of Four Processed Panax ginseng Products

In the food industry and herbal markets, it is critical to control the quality of processed Panax ginseng products. In this study, ultra-performance liquid chromatography coupled to quadrupole time of flight mass spectrometry (UPLC-QTOF/MS)-based metabolomics was applied for the quality evaluation of white ginseng (WG), tae-geuk ginseng (TG), red ginseng (RG), and black ginseng (BG). Diverse metabolites including ginsenosides were profiled by UPLC-QTOF/MS, and the datasets of WG, TG, RG, and BG were then subjected to multivariate analyses. In principal component analysis (PCA), four processed ginseng products were well-differentiated, and several ginsenosides were identified as major components of each product. S-plot also characterized the metabolic changes between two processed ginseng products, and the major ginsenosides of each product were found as follows: WG (M-Rb1, M-Rb2, M-Rc, Re, Rg1), TG (Rb2, Rc, Rd, Re, Rg1), RG (Rb1, Rb2, Rc, Rd, Re, Rg1), and BG (Rd, Rk1, Rg5, Rg3). Furthermore, the quantitative contents of ginsenosides were evaluated from the four processed ginseng products. Finally, it was indicated that the proposed metabolomics approach was useful for the quality evaluation and control of processed ginseng products.

Ginsenoside Rb1 exerts antidiabetic action on C2C12 muscle cells by leptin receptor signaling pathway

CONTEXT

Ginsenoside Rb1 improves insulin sensitivity and glucose uptake in muscle cells via different signaling pathways; however, it is not clear that it has any effect on leptin signaling in skeletal muscle.

OBJECTIVES

The aim of this study was to investigate the effect of ginsenoside Rb1 on leptin receptors expression and main signaling pathways of leptin (STAT3, PI3 kinase and ERK kinase) in C2C12 skeletal muscle cells.

MATERIALS AND METHODS

C2C12 myotubes were incubated with various concentrations of Rb1 (0.1, 1 and 10 μM) for different incubation times (1-12 h). Leptin receptors expression and GLUT-4 translocation were analyzed using realtime PCR and western blot analyses, respectively. PI3 and ERK kinases were blocked using their specific inhibitors (wortmannin and PD98059) in the presence and absence of RB1 to determine the main signaling pathway related to leptin receptor activation in C2C12 cells.

RESULTS

Rb1 could maximally stimulate both leptin receptors (OBRa and OBRb) mRNA and protein expression and phosphorylation of STAT3, PI3K and ERK2 in C2C12 myotubes at 10 μM for 3 h. Rb1 induced GLUT4 translocation was inhibited by the silencing of OBRb mRNA, demonstrated that glucose uptake was mediated via leptin receptor activation. GLUT4 recruitment to the cell surface induced by Rb1 was inhibited by wortmannin, an inhibitor of PI3K in combination with OBRb siRNA, but not by PD98059 an ERK2 kinase-1 inhibitor, indicating that GLUT4 translocation induced by Rb1 was associated with the leptin receptor upregulation and subsequent activation of PI3K.

CONCLUSIONS

Our results suggest that Rb1 promote translocation of GLUT4 by upregulation of leptin receptors and activation of PI3K.

Ginseng and obesity

Although ginseng has been shown to have an antiobesity effect, antiobesity-related mechanisms are complex and have not been completely elucidated. In the present study, we evaluated ginseng’s effects on food intake, the digestion, and absorption systems, as well as liver, adipose tissue, and skeletal muscle in order to identify the mechanisms involved. A review of previous in vitro and in vivo studies revealed that ginseng and ginsenosides can increase energy expenditure by stimulating the adenosine monophosphate-activated kinase pathway and can reduce energy intake. Moreover, in high fat diet-induced obese and diabetic individuals, ginseng has shown a two-way adjustment effect on adipogenesis. Nevertheless, most of the previous studies into antiobesity effects of ginseng have been animal based, and there is a paucity of evidence supporting the suggestion that ginseng can exert an antiobesity effect in humans.

Ginsenoside Rg3 prevents INS-1 cell death from intermittent high glucose stress

BACKGROUND

Ginsenoside Rg3 has been proposed to mediate anti-diabetic effects, but their direct effect on pancreatic β cell viability and mechanisms are not clearly understood. Recent studies suggest that intermittent high glucose (IHG) could be more harmful to pancreatic β cells than sustained high glucose. There are few reports about the effect of the ginsenosideRg3 to β cell apoptosis and proliferation against IHG.

METHODS

INS-1 cells were treated with alternative glucose concentration with or without ginsenoside Rg3. Cell apoptosis and viability were detected by Annexin V staining and MTT assay. The activation of mitogen-activated protein kinases (MAPKs) was analyzed by Western blotting using specific antibodies. Quantification of secreted insulin protein was measured using rat/mouse Insulin ELISA kits. Bromodeoxyuridine (BrdU) staining and florescence in situ hybridization (FISH) analysis was performed to compare cell proliferation.

RESULT

INS-1 cell viability was decreased under IHG and increased with Rg3 treatment.Rg3 significantly reduced the apoptotic INS-1 cells against IHG. The quantification of secreted insulin concentration was increased with Rg3. Rg3 increased INS-1 cell proliferation. ERK and p38 MAPK pathways reduced by IHG were activated by the ginsenoside Rg3.

CONCLUSION

Ginsenoside Rg3 protected INS-1 cell death from IHG with reducing apoptosis and increasing proliferation.

Ginsenoside Rb1 stimulates adiponectin signaling in C2C12 muscle cells through up-regulation of AdipoR1 and AdipoR2 proteins

CONTEXT

Rb1 ginsenoside, the key element of ginseng root, is widely used as an herbal therapeutic drug in diabetic patients. Various hypoglycemic mechanisms have been described for Rb1; however, to date, there has been no report on the effect of Rb1 on adiponectin signaling.

OBJECTIVES

The current study was performed to establish the effects of ginsenoside Rb1 on the gene expression of AdipoR1 and AdipoR2 and their correlation to GLUT4 translocation in C2C12 myocytes.

MATERIALS AND METHODS

C2C12 myotubes were incubated with various concentrations of Rb1 (0.001-100 µM) for different incubation times (1-12 h). Real time PCR and western blot analyses were performed to investigate the expression changes of adiponectin receptors (AdRs) and GLUT4 translocation, respectively. Gene silencing of AdipoR1 using specific siRNA was used to determine whether inhibition of AdipoR1 would reduce Rb1-induced GLUT-4 translocation in C2C12 cells.

RESULTS

Rb1 significantly stimulated basal AdRs expression levels in a time and dose-dependent manner; the maximal effect was attained at a concentration of 100 µM and a time of 3 h (p < 0.05). In muscle cells, Rb1 increased GLUT4 translocations to the cell surface, which was correlated with increasing the adiponectin receptors gene expression. Rb1-induced GLUT4 translocation was inhibited by the silencing of AdipoR1 mRNA.

DISCUSSION AND CONCLUSION

These results suggest that ginsenoside Rb1 promote translocations of GLUT4 by activating the adiponectin signaling pathway. The results can be helpful in understanding the novel antidiabetic mechanism of Rb1 ginsenoside and gain further support for its use as an antidiabetic drug.

Protective Effect of Heat-processed Ginseng (Sun Ginseng) in the Adenine-induced Renal Failure Rats

The effect of orally administered sun ginseng (SG), which is a ginseng processed by steaming, was examined in adenine-induced chronic renal failure rat. SG significantly decreased both blood urea nitrogen and serum creatinine levels, indicating an improvement of renal function. Also, SG significantly increased the urinary excretion of both urea and creatinine. Furthermore it lowered the blood pressure, and inhibited adenine-induced kidney hypertrophy and edema. Based on these findings, SG may ameliorate chronic renal failures.