American ginseng (Panax quinquefolius L) reduces postprandial glycemia in nondiabetic subjects and subjects with type 2 diabetes mellitus

Ginsenoside Rb1 increases insulin sensitivity by activating AMP-activated protein kinase in male rats

Although ginseng has been reported to ameliorate hyperglycemia in animal models and clinical studies, the molecular mechanisms are largely unknown. We previously reported that chronic treatment with ginsenoside Rb1 (Rb1), a major component of ginseng, significantly reduced fasting glucose and improved glucose tolerance in high-fat diet (HFD)-induced obese rats. These effects were greater than those observed in pair-fed rats, suggesting a direct effect of Rb1 on glucose homeostasis, and this possibility was confirmed in the present study. In lean rats fed standard rodent chow, 5-day treatment with Rb1 significantly improved glucose tolerance and enhanced insulin sensitivity. Notably, those effects were not accompanied by reduced food intake or changed body weight. To elucidate the underlying molecular mechanisms, rats fed a HFD for 4 weeks were treated with Rb1 for 5 days. Subsequently, euglycemic-hyperinsulinemic clamp studies found that compared to vehicle, Rb1, while not changing food intake or body weight, significantly increased glucose infusion rate required to maintain euglycemia. Consistent with this, insulin-induced inhibition of hepatic gluconeogenesis was significantly enhanced and hepatic phosphoenolpyruvate carboxykinase and glucose-6-phosphatase gene expression was suppressed. Additionally, glucose uptake was significantly increased in skeletal muscle. While proximal insulin signaling was not changed after Rb1 treatment, increased phosphorylation of TBC1D4, a downstream target of AMPK signaling, appears to be a key part of the mechanism for Rb1-stimulated glucose uptake in skeletal muscle. These findings indicate that Rb1 has multiple effects on glucose homeostasis, and provide strong rationale for further evaluation of its potential therapeutic role.

Insulin combined with Chinese medicine improves glycemic outcome through multiple pathways in patients with type 2 diabetes mellitus

Introduction/Aims

Insufficient insulin secretion or inefficient insulin response are responsible for the clinical outcome of type 2 diabetes mellitus. Administration of insulin alone is prone to cause secondary effects, resulting in an unsatisfactory outcome. Shen-Qi-Formula (SQF), a well-known Chinese medicinal formula, has been used for diabetic treatment for a long time. The present study was designed to investigate whether SQF in combination with insulin improved the clinical outcome of type 2 diabetes mellitus, and what mechanisms were possibly involved in the treatment.

Materials and Methods

A total of 219 patients were included in the study. Of these, 110 patients were treated with insulin monotherapy, and 109 with the combination therapy of SQF and insulin. Before and after 12-week treatment, the fasting blood glucose, postprandial blood glucose, β-cell function, insulin resistance and blood lipids were measured.

Results

The 12 weeks of SQF treatment in combination with insulin significantly decreased the fasting and postprandial blood glucose levels. Insulin secretion was not increased after the treatment, but β-cell function and insulin resistance were obviously improved. Furthermore, 12 weeks of treatment with SQF and insulin improved the levels of glucagon-like peptide-1, oxidative stress, blood lipids, coagulation function and bodyweight.

Conclusion

The results from our study showed that the combination therapy of SQF and insulin significantly improved the clinical outcome of type 2 diabetes mellitus compared with insulin monotherapy. The mechanism of improvement was possibly involved in the multiple pathways.

Chemical differentiation and quality evaluation of commercial Asian and American ginsengs based on a UHPLC-QTOF/MS/MS metabolomics approach

INTRODUCTION

Asian and American ginsengs are widely used medicinal materials and are being used more and more in health products. The two materials look alike but function differently. Various forms of both types of ginseng are found in the market, causing confusion for consumers in their choice.

OBJECTIVE

To evaluate the overall quality of commercial Asian and American ginsengs and investigate the characteristic chemical markers for differentiating between them.

METHODS

This article investigated 17 Asian and 21 American ginseng samples using an ultra-HPLC combined with quadrupole time-of-flight MS/MS technique. The data were processed by principal component analysis and orthogonal partial least squared discriminant analysis.

RESULTS

In the chromatograms, a total of 40 peaks were detected. Among them, six were positively identified, and all of the remainder were tentatively identified. According to statistical results, ginsenosides Rf, Rb2 and Rc together with their isomers and derivatives were more likely to be present in Asian ginsengs, whereas ginsenoside Rb1 , pseudoginsenoside F11 and ginsenoside Rd together with their isomers and derivatives tended to be present in American ginsengs. For Asian ginsengs, ginsenoside Ra3 and 20-β-D-glucopyranosyl-ginsenoside-Rf were more likely to be present in forest samples, whereas contents of floralquinquenoside B, ginsenosides Ro and Rc, and zingibroside R1 were higher in sun-dried ginsengs. For American ginseng, wild samples often had more of the notoginsenosides R1 and Rw2 and less of the ginsenosides Rd, Rd isomer and 20 (S)-Rg3 than cultivated samples.

CONCLUSION

The method provided important fingerprint information for authentication and evaluation of Asian and American ginsengs from various commercial products.

Improved working memory performance following administration of a single dose of American ginseng (Panax quinquefolius L.) to healthy middle-age adults

OBJECTIVE

A ginsenoside-rich extract of American ginseng (Panax quinquefolius L.), Cereboost(TM), was previously shown to improve working memory and mood in healthy young individuals. The present study represented a partial replication investigating whether these effects extended to healthy middle-aged individuals.

METHODS

Fifty-two healthy volunteers (40-60 years old, mean age 51.63) received 200 mg of P. quinquefolius or a matching placebo according to a double-blind, placebo-controlled, balanced, crossover design. The Cognitive Drug Research battery and the Computerised Mental Performance Assessment System were used to evaluate cognitive performance at baseline then 1, 3 and 6 h following treatment. Blood glucose and mood were co-monitored.

RESULTS

Compared with placebo, P. quinquefolius improved cognitive performance on 'Working Memory' factor at 3 h. Similar effects were observed in one of the two tasks making up this factor, spatial working memory. There were no significant effects on mood or blood glucose levels.

CONCLUSIONS

These data confirm that P. quinquefolius can acutely benefit working memory and extend the age range of this effect to middle-aged individuals. These changes are unlikely to be underpinned by modulation of blood glucose in this population.

Salacia reticulata (Kothala himbutu) revisited; a missed opportunity to treat diabetes and obesity?

Background

Nearly 50% of diabetic patients worldwide use complementary medicines to treat or supplement their conventional diabetes treatment. Salacia reticulata (Kothala himbutu) is a woody climber used widely in the Ayurvedic system to treat diabetes and obesity.

Objective

In this review I critically analyze the evidence for using Salacia reticulata for treating type 2 diabetes and obesity. The available evidence is described in terms of in-vitro studies, animal studies and clinical trials.

Results and conclusions

In vitro studies demonstrate the ability of Salacia to inhibit intestinal alpha glucosidase. In mouse mesenteric fat it enhances the mRNA expression for hormone sensitive lipase (HSL) and adiponectin; thus increasing lipolysis and reducing insulin resistance respectively. In 3 T3-L-1 adipocytes lipogenesis factors are down regulated and lipolysis factors are up regulated with Salacia reticulata treatment. Animal studies and clinical trials are consistent in demonstrating improvement of glucose concentrations in the fasted and sucrose and maltose loaded states. Clinically significant reductions of HbA1C and plasma Insulin are reported with treatment of 6 weeks to 3 months. One clinical trial reported significant reduction of weight and BMI when Salacia is used in combination with vitamin D.

Salacia reticulata effectively improves insulin resistance, glucose metabolism and reduces obesity. A larger evidence base is required from well-planned studies to confirm its efficacy and safety.

Promoting effect of triterpenoid compound from Agrimonia pilosa Ledeb on preadipocytes differentiation via up-regulation of PPARγ expression

Background:

Agrimonia Pilosa Ledeb (APL), a traditional Chinese medicine, has been reported a variety of biological activities, including treating T2DM.

Objective:

Triterpenoid compound (TC) was collected from APL. The aim of this study was to investigate the effects of TC on 3T3-L1 preadipocytes differentiation and genes related to differentiation and IR.

Materials and Methods:

Column chromatography was used to collect TC from ALP. 3T3-L1 cell differentiation was induced typically in the presence of various concentrations of TC or pioglitazone. Oil red O staining and measurement of intracellular TG content were performed on the seventh day of differentiation. Then quantitative polymerase chain reaction (Q-PCR) was used to test the expressions of three transcription factors (PPARγ, CCAAT enhancer binding protein-α (C/EBP-α), and sterol regulatory element-binding protein 1 (SREBP-1)) and the target genes of PPARγ including glucose transporter (GLUT4), lipoprotein lipase (LPL), fat acid binding protein (AP2), and adiponectin in 3T3-L1 cells.

Results:

At the concentration of 5, 25 and 125 μg/mL, TC significantly promoted triglyceride accumulation. Further study showed that TC could promote the expression of PPARγ, C/EBPα and ADD1/SREBP1 significantly at 125 μg/mL. As for downstream genes controlled by PPARγ, TC at 25 and 125 μg/mL could significantly promote the expression of GLUT4 and adiponectin. However, the expression of aP2 related to lipid metabolism and adiposity in the TC group was significantly lower than that in the pioglitazone group.

Conclusion:

TC could promote preadipocytes differentiation through activating PPARγ and downstream controlled genes. TC has the ideal insulin sensitization with lower adipogenic action than classical TZDs in vitro. So TC from Agrimonia Pilosa Ledeb has a good prospect as a natural drug for IR and T2DM.

Alternative Medicine in Diabetes - Role of Angiogenesis, Oxidative Stress, and Chronic Inflammation

Diabetes is a chronic metabolic disorder that is characterized by hyperglycemia due to lack of or resistance to insulin. Patients with diabetes are frequently afflicted with ischemic vascular disease and impaired wound healing. Type 2 diabetes is known to accelerate atherosclerotic processes, endothelial cell dysfunction, glycosylation of extracellular matrix proteins, and vascular denervation. Herbal medicines and naturally occurring substances may positively affect diabetes management, and could thus be utilized as cost-effective means of supporting treatment in developing countries. Natural treatments have been used in these countries for a long time to treat diabetes. The present review analyses the features of aberrant angiogenesis, abnormalities in growth factors, oxidative stress, and metabolic derangements relevant to diabetes, and how herbal substances and their active chemical constituents may counteract these events. Evidence for possible biochemical effectiveness and limitations of herbal medicines are given, as well as details regarding the role of cytokines and nitric oxide.

American ginseng regulates gene expression to protect against premature ovarian failure in rats

Premature ovarian failure (POF) is defined as lost ovarian functions before the age of 40. Three possible molecular markers (PLA2G4A, miR-29a, and miR-144) have been identified in our previous study by integrated analysis of mRNA and miRNA expression profiles. The present study aimed to evaluate American ginseng root's protective potential against POF by studying transcriptional and protein variations between American ginseng treatments and controls in rats. 4-Vinylcyclohexene diepoxide (VCD) was administered to rats for 14 days to induce POF. Additionally, American ginseng was administered to POF rats for one month, and PLA2G4A, miR-29a, and miR-144 expressions were measured in rat ovaries by qRT-PCR. PLA2G4A protein expression was examined by Western Blot, and PGE₂, LH, FSH, and E2 serum levels were detected by ELISA. PLA2G4A mRNA and protein were downregulated in American ginseng-treated rats, miR-29a and miR-144 levels increased, and PGE₂ serum levels decreased, while LH, FSH, and E2 increased compared to POF induction alone. Analysis of transcriptional and protein variations suggested that American ginseng protects the ovary against POF by regulating prostaglandin biosynthesis, ovulation, and preventing ovarian aging. High hormone levels (PGE₂, FSH, and LH) were reduced, and E2 secretion approached normal levels, leading to improved POF symptoms and abnormal ovulation.

Ethanol extraction preparation of American ginseng (Panax quinquefolius L) and Korean red ginseng (Panax ginseng C.A. Meyer): differential effects on postprandial insulinemia in healthy individuals

ETHNOPHARMACOLOGICAL RELEVANCE

Ginsenosides are the proposed bioactive constituent of ginseng, especially for the attenuation of postprandial glycemia (PPG). The efficacious proportion of total and specific ginsenosides, remains unknown. Alcohol extraction of whole ginseng root can be used to selectively manipulate the ginsenoside profile with increasing alcohol concentrations producing high yields of total ginsenosides and varying their individual proportions.

AIM OF THE STUDY

We aimed to compare the acute efficacy of different ethanol-extraction preparations of American ginseng (AG) and Korean red ginseng (KRG), with their whole-root origins, on PPG and insulin parameters in healthy adults.

MATERIALS AND METHODS

Following an overnight fast, 13 healthy individuals (Gender: 5M:8F, with mean ± SD, age: 28.9 ± 9.2 years, BMI: 26.3 ± 2.7 kg/m(2) and fasting plasma glucose: 4.21 ± 0.04 mmol/L) randomly received 3g of each of the following 10 different ginseng treatments on separate visits: whole root KRG and AG; 30%, 50% or 70% ethanol extracts of KRG and AG and 2 cornstarch placebos. Treatments were consumed 40 min prior to a 50 g oral glucose challenge test with capillary blood samples collected at baseline, 15, 30, 45, 60, 90 and 120 min. Insulin samples were collected at 0, 30, 60 and 120 min.

RESULTS

There was no difference in attenuation of PPG among the tested ginseng preparations. Measures of Insulin Sensitivity Index (ISI) showed increased insulin sensitivity (IS) with KRG-30% and AG-50% extracts compared to placebo (p<0.05).

CONCLUSIONS

The insulin sensitizing effects of KRG-30% and AG-50% extracts suggest that other root parts, including other ginsenosides not typically measured, may influence PPG and insulin parameters. There is potential for AG and KRG extracts to modulate IS, an independent predictor of type 2 diabetes.

Randomized, double-blind, placebo-controlled, clinical study on the effect of Diabetinol(®) on glycemic control of subjects with impaired fasting glucose

BACKGROUND

This study investigated the efficacy of Diabetinol(®) in people with diabetes on medication but not meeting the American Association of Clinical Endocrinologists and American Diabetes Association glycemic, blood pressure, and lipid targets.

SUBJECTS AND METHODS

Fifty subjects, aged 18-75 years, with fasting blood glucose ≤15.4 mmol/L, hemoglobin A1c levels ≤12%, and a body mass index between 25 and 40 kg/m(2), were enrolled in a 24-week, randomized, double-blind, placebo-controlled, parallel study. Diabetinol(®) or placebo was administered as 2×525 mg capsules/day.

RESULTS

In the Diabetinol(®) group, 14.3% versus 0% in the placebo group, 33.3% versus 15.4% in placebo, 20.0% versus 12.5% in placebo, and 83.3% versus 60% in placebo achieved the American Association of Clinical Endocrinologists and American Diabetes Association targets for hemoglobin A1c, low-density lipoprotein, total cholesterol, and systolic blood pressure, respectively. There was no difference in the maximum concentration (Cmax) of serum glucose or area under the curve (AUC)0-240 minutes. The time to Cmax was longer for participants on Diabetinol(®) than placebo group at week 12 (P=0.01). Fasting blood glucose increased from baseline to week 24 in both groups; however, this increase was 14.3 mg/dL lower in the Diabetinol(®) group versus placebo. The Diabetinol(®) group showed an increase of 5.53 mg/dL in fasting insulin at week 12 (P=0.09) and 3.2 mg/dL at week 24 (P=0.41) over and above the placebo group. A decrease of 1.5% in total cholesterol, 5.8% in low-density lipoprotein, and a 1.6% increase in high-density lipoprotein concentrations were seen in the Diabetinol(®) group. Diabetinol(®) improved 6-month oral glucose tolerance test and 2-hour postprandial glucose profiles in participants between 40 and 60 years of age.

CONCLUSION

The current study suggests a role for Diabetinol(®) as an adjunctive therapy for glycemic maintenance and for decreasing the risk of diabetes-associated comorbidities in type 2 diabetic patients on conventional therapies.

Interactions between herbs and antidiabetics: an overview of the mechanisms, evidence, importance, and management

Complementary and alternative therapies are quickly gaining importance because they are perceived to be free of side effects due to their natural origin. However, herbal remedies are complex mixtures of bioactive entities, which may interact with prescription drugs through pharmacokinetic or pharmacodynamic mechanisms and sometimes result in life-threatening consequences. In particular, diabetes patients are often treated with multiple medications due to different comorbidities, and such patients use antidiabetic medications for their entire lives; thus, it is important to make the public aware of herb interactions with antidiabetic drugs. In this paper, we summarize the reports available on the interaction of herbal remedies with oral hypoglycemic agents and describe mechanisms, preclinical or clinical evidence, importance, and management strategies.

The use of complementary and alternative medicines (CAMs) in the treatment of diabetes mellitus: is continued use safe and effective?

INTRODUCTION

Diabetes mellitus is a major cause of morbidity and mortality worldwide, with a prevalence of 347 million in 2013. Complementary and Alternative Medicines (CAM) are a group of remedies that is fast gaining acceptance among individuals. Cinnamon, Bitter gourd (Momordica charantia) and Fenugreek (Trigonella foenum-graecum) are 3 widely used CAMs used worldwide for the treatment of diabetes. Data on safety and efficacy is limited, but the consumption is wide. Crepe ginger (Costus speciosus) and Ivy gourd (Coccinia grandis) are 2 plants used widely in the Asian region for their presumed hypoglycaemic properties.

OBJECTIVE

In this review, we analyzed the available evidence for the 5 CAMs mentioned above in terms of in-vitro studies, animal studies sand clinical trials. We also describe the mechanisms of hypoglycaemia and safety concerns where there is available evidence.

RESULTS AND CONCLUSIONS

Clinical trials that studied the hypoglycaemic effects of Cinnamon, bitter gourd, fenugreek and ivy gourd showed conflicting results. Direct comparison between studies remains a challenge in view of the baseline heterogeneity of subjects, differences in substrate preparation, variable end points and poor trial design. Short durations of study and small number of subjects studied is universal. Crepe ginger has not been studied adequately in humans to draw conclusions.In view of the high prevalence of use and safety and efficacy issues, there is an urgent need to study their hypoglycaemic and adverse effects in well-designed long-term clinical trials.

Use of Complementary and Alternative Medicines (CAMs) among type 2 diabetes patients in Sri Lanka: a cross sectional survey

BACKGROUND

The incidence of chronic illnesses has increased worldwide. Diabetes is one such illness and 80% of the diabetic population lives in the developing world. There is a rapidly growing trend towards the use of Complementary and Alternative Medical practices in Diabetes. Sri Lanka is a developing Asian nation with a rich culture of Ayurvedic and native medical culture. The objective of this study was to find the prevalence of use of CAMs in a diabetic population attending a large multiethnic diabetes facility in a University unit and to assess whether there is an increase in the incidence of hypoglycaemic episodes among users of CAMs.

METHODS

A cross sectional study was performed at Teaching Hospital Peradeniya between April and August 2012. Following verbal consent, 254 type 2 adult diabetic patients attending the diabetes facility were interviewed regarding the use of CAM and hypoglycaemia using an interviewer-administered questionnaire.

RESULTS

Of the 252 valid results, 192 patients (76%) admitted to the use of a CAM to reduce blood glucose. Bitter gourd, ivy gourd and crepe ginger were used by 128, 113 and 92 individuals. While 19% used a single agent, 34%, 21% and 2.4% used 2,3 and more than 3 agents. The incidence of hypoglycaemia in CAM users was 21% and 16.6% in non-users. The difference was statistically not significant. (p = 0.57) Ingestion of Costus speciosus (Crepe ginger) was associated with higher incidence of hypoglycaemia (P = 0.01).Female gender was significantly associated with CAM use (p = 0.01), while the age, duration of diabetes, presence of co-morbidities and complications of diabetes failed to show a significant association.

CONCLUSION

Sri Lanka has a very high use of herbal supplementation in type 2 diabetes patients. Although the overall incidence of hypoglycaemia is not increased among CAM users, crepe ginger is associated with significant hypoglycaemia and warrants further research.

Effects of Korean White Ginseng (Panax Ginseng C.A. Meyer) on Vascular and Glycemic Health in Type 2 Diabetes: Results of a Randomized, Double Blind, Placebo-controlled, Multiple-crossover, Acute Dose Escalation Trial

Korean red ginseng (steam treated Panax ginseng C.A. Meyer), among most prized traditional herbal remedies, has been clinically shown to improve cardiovascular disease (CVD) risk factors. Whether this holds true for the dried non-steamed variety, known as Korean white ginseng (KWG) is unclear. This study therefore, investigated the efficacy and safety of escalating doses of KWG on vascular and glycemic parameters in type 2 diabetes (T2DM). Using an acute, randomized, placebo-controlled, double-blind, crossover design, 25 participants with well-controlled T2DM (12-males: 13-females, age: 63 ± 9 years, A1c: 6.9 ± 0.7%, BMI: 29.3 ± 4.3 kg/m²) underwent five visits during which they received 1 g, 3 g, or 6 g KWG or 3 g wheat-bran control (twice) together with 50 g-glucose load. For the duration of 240 minutes, augmentation index (AI), and central blood pressure were measured at baseline and at 60 min-intervals, and ambulatory blood pressure was assessed at baseline and at 10 min-intervals. Additionally, capillary blood was collected at time zero and at 15, 30, 45, 60, 90, 120, and 180 minutes post-treatment. A symptoms questionnaire was used to assess safety and adverse events. Two-way ANOVA demonstrated a significant time-treatment interaction effect on AI (p = 0.01) with one-way ANOVA showing significant reductions in AI with 3 g KWG relative to control (p = 0.04). Compared to control, acute administration of KWG appeared to be safe, but did not affect any other postprandial, vascular or glycemic parameters. KWG might have a beneficial effect on AI, a cumulative indicator of arterial health. However, these results are preliminary and highlight the need for long-term investigation with a focus on its accountable components. Clinical Trial Registration: NCT01699074

Best herbs for managing diabetes: a review of clinical studies

Diabetes mellitus is a public health problem which leads to serious complications over time. Experimentally, many herbs have been recommended for treating diabetes. In most cases, however, the recommendations are based on animal studies and limited pieces of evidence exist about their clinical usefulness. This review focused on the herbs, the hypoglycemic actions of which have been supported by three or more clinical studies. The search was done in Google Scholar, Medline and Science Direct databases using the key terms diabetes, plants, herbs, glucose and patients. According to the clinical studies, Aegle marmelos, Allium cepa, Gymnema sylvestre, Momordica charantia, Ocimum sanctum, Nigella sativa, Ocimum sanctum, Panax quinquefolius, Salacia reticulate, Silybum marianum and Trigonella foenum-graecum have shown hypoglycemic and, in some cases, hypolipidemic activities in diabetic patients. Among them, Gymnema sylvestre, Momordica charantia, Silybum marianum and Trigonella foenum-graecum have acquired enough reputation for managing diabetes. Thus, it seems that physicians can rely on these herbs and advise for the patients to improve management of diabetes.

Ginseng and diabetes: the evidences from in vitro, animal and human studies

Panax ginseng exhibits pleiotropic beneficial effects on cardiovascular system, central nervous system, and immune system. In the last decade, numerous preclinical findings suggest ginseng as a promising therapeutic agent for diabetes prevention and treatment. The mechanism of ginseng and its active components is complex and is demonstrated to either modulate insulin production/secretion, glucose metabolism and uptake, or inflammatory pathway in both insulin-dependent and insulin-independent manners. However, human studies are remained obscure because of contradictory results. While more studies are warranted to further understand these contradictions, ginseng holds promise as a therapeutic agent for diabetes prevention and treatment. This review summarizes the evidences for the therapeutic potential of ginseng and ginsenosides from in vitro studies, animal studies and human clinical trials with a focus on diverse molecular targets including an AMP-activated protein kinase signaling pathway.

Increase in Insulin Secretion Induced by Panax ginseng Berry Extracts Contributes to the Amelioration of Hyperglycemia in Streptozotocininduced Diabetic Mice

Panax ginseng has long been used as a traditional herbal medicine. More recently, it has received attention for its anti-diabetic and anti-obesity effects in humans and in animal models of type 2 diabetes. In the present study, we tested the hypoglycemic effects of ginseng berry extract in beta-cell-deficient mice and investigated the mechanisms involved. Red (ripe) and green (unripe) berry extracts were prepared and administered orally (100 or 200 mg/kg body weight) to streptozotocin-induced diabetic mice daily for 10 wk. The body weight was measured daily, and the nonfasting blood glucose levels were measured after 5 and 10 wk after administration. Glucose tolerance tests were performed, and the serum insulin levels were measured. The proliferation of betacells was measured in vitro. The administration of red or green ginseng berry extract significantly reduced the blood glucose levels and improved the glucose tolerance in beta-cell deficient mice, with the higher doses resulting in better effects. Glucose-stimulated insulin secretion was significantly increased in berry extract-treated mice compared with streptozotocin-induced diabetic control mice. Treatment with ginseng berry extract increased beta-cell proliferation in vitro. Both red berry and green berry extracts improved glycemic control in streptozotocin-induced diabetic mice and increased insulin secretion, possibly due to increased beta-cell proliferation. These results suggest that ginseng berry extracts might have beneficial effects on beta-cell regeneration.

Ginsenoside Re reduces insulin resistance through activation of PPAR-γ pathway and inhibition of TNF-α production

ETHNOPHARMACOLOGICAL RELEVANCE

Panax ginseng is a well-known traditional Chinese medicine and has been used for treatment of various diseases for more than four thousand years in Asia. Ginseng saponins or ginsenosides, the active constituents are reported to possess antidiabetic activity, but their antihyperglycemic mechanisms are not fully elucidated. In the present study, the mechanisms of action of ginsenoside Re were investigated in vitro models.

MATERIALS AND METHODS

3T3-L1 cells were chosen as the model to investigate the molecular mechanisms of action of ginsenoside Re. Influence of ginsenoside Re on the adipogenesis was examined by determining TG levels in 3T3-L1 adipocytes by the method of TG oxidation enzyme. Glucose uptake in 3T3-L1 cells stimulated by insulin in the absence or presence of ginsenoside Re were quantified by measuring (3)H-2-deoxy-d-glucose levels. Cytokine proteins released into the medium including adiponectin and TNF-α were tested using respective ELISA kits. In addition, real time RT-PCR was conducted to investigate the expression changes of PPAR-γ and its responsive genes, ap2, adiponectin, IRS-1, GLUT4 and TNF-α. And western blot analysis was performed to determine the translocation of GLUT4. Finally, effects of ginsenoside Re on NO production in 3T3-L1 adipocytes and in macrophages were investigated through measurement of nitrite concentration by Griess reagent.

RESULTS

Ginsenoside Re induced adipogenesis of 3T3-L1 adipocytes by accumulating TG, increased glucose uptake and up-regulated PPAR-γ2, IRS-1, ap2 and adiponectin genes expressions. Meanwhile, Re also increased production and release of adiponectin. Although having no effects on GLUT4 gene expression, Re facilitated GLUT4 protein translocation to the membranes. In addition, Re inhibited the expression and release of TNF-α. Finally, Re did not show inhibitory effects on NO production both in 3T3-L1 cells stimulated by LPS, TNF-α and IFN-γ and in LPS-stimulated mouse peritoneal macrophages.

CONCLUSIONS

Ginsenoside Re exhibited the action of reducing insulin resistance through activation of PPAR-γ pathway by directly increasing the expressions of PPAR-γ2 and its responsive genes, adiponectin, IRS-1, ap2, inhibiting TNF-α production and facilitating the translocation of GLUT4 to promote glucose uptake and disposal in 3T3-L1 adipocytes.

Treating type 2 diabetes mellitus with traditional chinese and Indian medicinal herbs

Type II diabetes mellitus (T2DM) is a fast-growing epidemic affecting people globally. Furthermore, multiple complications and comorbidities are associated with T2DM. Lifestyle modifications along with pharmacotherapy and patient education are the mainstay of therapy for patients afflicted with T2DM. Western medications are frequently associated with severe adverse drug reactions and high costs of treatment. Herbal medications have long been used in the treatment and prevention of T2DM in both traditional Chinese medicine (TCM) and traditional Indian medicine (TIM). This review examines in vivo, in vitro, and clinical evidence supporting the use of various herbs used in TCM and TIM. The problems, challenges, and opportunities for the incorporation of herbal frequently used in TCM and TIM into Western therapy are presented and discussed.

Increased glucagon-like peptide-1 secretion may be involved in antidiabetic effects of ginsenosides

Panax ginseng is one of the most popular herbal remedies. Ginsenosides, major bioactive constituents in P. ginseng, have shown good antidiabetic action, but the precise mechanism was not fully understood. Glucagon-like peptide-1 (GLP1) is considered to be an important incretin that can regulate glucose homeostasis in the gastrointestinal tract after meals. The aim of this study was to investigate whether ginseng total saponins (GTS) exerts its antidiabetic effects via modulating GLP1 release. Ginsenoside Rb1 (Rb1), the most abundant constituent in GTS, was selected to further explore the underlying mechanisms in cultured NCI-H716 cells. Diabetic rats were developed by a combination of high-fat diet and low-dose streptozotocin injection. The diabetic rats orally received GTS (150 or 300 mg/kg) daily for 4 weeks. It was found that GTS treatment significantly ameliorated hyperglycemia and dyslipidemia, accompanied by a significant increase in glucose-induced GLP1 secretion and upregulation of proglucagon gene expression. Data from NCI-H716 cells showed that both GTS and Rb1 promoted GLP1 secretion. It was observed that Rb1 increased the ratio of intracellular ATP to ADP concentration and intracellular Ca2+ concentration. The metabolic inhibitor azide (3 mM), the KATP channel opener diazoxide (340 μM), and the Ca2+ channel blocker nifedipine (20 μM) significantly reversed Rb1-mediated GLP1 secretion. All these results drew a conclusion that ginsenosides stimulated GLP1 secretion both in vivo and in vitro. The antidiabetic effects of ginsenosides may be a result of enhanced GLP1 secretion.

Nutrient- and non-nutrient-based natural health product (NHP) use in adults with mood disorders: prevalence, characteristics and potential for exposure to adverse events

BACKGROUND

To address knowledge gaps regarding natural health product (NHP) usage in mental health populations, we examined their use in adults with mood disorders, and explored the potential for adverse events.

METHODS

Food and NHP intake was obtained from 97 adults with mood disorders. NHP data was used to compare prevalence with population norms (British Columbia Nutrition Survey; BCNS). Bivariate and regression analyses examined factors associated with NHP use. Assessment of potential adverse effects of NHP use was based on comparing nutrient intakes from food plus supplements with the Dietary Reference Intakes and by reviewing databases for reported adverse health effects.

RESULTS

Two-thirds (66%; 95% CI 56 to 75) were taking at least one NHP; 58% (95% CI 47 to 68) were taking NHPs in combination with psychiatric medications. The proportion of each type of NHP used was generally higher than the BCNS (range of p's < 0.05 to 0.0001). When intakes from food and NHP sources were combined, a small proportion exceeded any Lowest-Observed-Adverse-Effect-Levels: only for niacin (n = 17) and magnesium (n = 6), two nutrients for which the potential for adverse effects is minimal. Conversely, about 38% (95% CI 28 to 49) of the sample were taking a non-nutrient based NHP for which previous adverse events had been documented.

CONCLUSIONS

The prevalent use of NHPs in this population suggests that health care providers need to be knowledgeable about their characteristics. The efficacy and safety of NHPs in relation to mental health warrants further investigation.

Herbal therapies for type 2 diabetes mellitus: chemistry, biology, and potential application of selected plants and compounds

Diabetes mellitus has been recognized since antiquity. It currently affects as many as 285 million people worldwide and results in heavy personal and national economic burdens. Considerable progress has been made in orthodox antidiabetic drugs. However, new remedies are still in great demand because of the limited efficacy and undesirable side effects of current orthodox drugs. Nature is an extraordinary source of antidiabetic medicines. To date, more than 1200 flowering plants have been claimed to have antidiabetic properties. Among them, one-third have been scientifically studied and documented in around 460 publications. In this review, we select and discuss blood glucose-lowering medicinal herbs that have the ability to modulate one or more of the pathways that regulate insulin resistance, β-cell function, GLP-1 homeostasis, and glucose (re)absorption. Emphasis is placed on phytochemistry, anti-diabetic bioactivities, and likely mechanism(s). Recent progress in the understanding of the biological actions, mechanisms, and therapeutic potential of compounds and extracts of plant origin in type 2 diabetes is summarized. This review provides a source of up-to-date information for further basic and clinical research into herbal therapy for type 2 diabetes. Emerging views on therapeutic strategies for type 2 diabetes are also discussed.

Herbal therapies for type 2 diabetes mellitus: chemistry, biology, and potential application of selected plants and compounds

Background:

Diabetes mellitus, becoming the third killer of mankind after cancer and cardiovascular diseases, is one of the most challenging diseases facing health care professionals today. That is why; there has been a growing interest in the therapeutic use of natural products for diabetes, especially those derived from plants.

Aim:

To evaluate the anti-diabetic activity together with the accompanying biological effects of the fractions and the new natural compounds of Hyphaene thebaica (HT) epicarp.

Materials and Methods:

500 g of coarsely powdered of (HT) fruits epicarp were extracted by acetone. The acetone crude extract was fractionated with methanol and ethyl acetate leaving a residual water-soluble fraction WF. The anti-diabetic effects of the WF and one of its compounds of the acetone extract of the (HT) epicarp were investigated in this study using 40 adult male rats.

Results:

Phytochemical investigation of active WF revealed the presence of ten different flavonoids, among which two new natural compounds luteolin 7-O-[6”-O-α-Lrhamnopyranosyl]-β-D-galactopyranoside 3 and chrysoeriol 7-O-β-D-galactopyranosyl(1→2)-α-L-arabinofuranoside 5 were isolated. Supplementation of the WF improved glucose and insulin tolerance and significantly lowered blood glycosylated hemoglobin levels. On the other hand, compound 5 significantly reduced AST and ALT levels of liver, respectively. Likewise, the kidney functions were improved for both WF and compound 5, whereby both urea and creatinine levels in serum were highly significant

Conclusion:

The results justify the use of WF and compound 5 of the (HT) epicarp as anti-diabetic agent, taking into consideration that the contents of WF were mainly flavonoids

Antidiabetic effects of malonyl ginsenosides from Panax ginseng on type 2 diabetic rats induced by high-fat diet and streptozotocin

ETHNOPHARMACOLOGY RELEVANCE

Ginseng (Panax ginseng C. A. Meyer) has been recorded to treat 'Xiao-ke' (emaciation and thirst) symptom in many ancient Chinese medical literatures (such as 'Shen Nong Ben Cao Jing') for thousands of years. 'Xiao-ke' symptom, in general, indicates diabetes mellitus.

AIM OF THE STUDY

Malonyl ginsenosides (MGR) are natural ginsenosides which exist in both fresh and air-dried ginseng. The objective of this study is to determine the antidiabetic function of MGR on type 2 diabetes.

MATERIALS AND METHODS

High fat diet-fed and streptozotocin-induced diabetic rats were treated with 50 and 100mg/kg/d of MGR or vehicle for 3 weeks. The effects of MGR on fasting blood glucose (FBG), intraperitoneal glucose tolerance test (IPGTT), serum insulin (SI), insulin tolerance test (ITT), body weight, total cholesterol (TC), and triglyceride (TG) levels in type 2 diabetic rats were measured.

RESULTS

After 3 weeks of treatment, MGR administration showed significantly lower FBG levels compared to the diabetic control group. In glucose tolerance test, IPGTT data showed that both MGR 50 and 100mg/kg groups significantly increased the glucose disposal after glucose load. The ITT also showed improvement of insulin sensitivity during 120 min of insulin treatment. In addition, MGR reduced TG and TC contents while showed no effect on body weight in diabetic rats.

CONCLUSION

The findings from this study suggest that MGR can alleviate hyperglycemia, hyperlipemia and insulin resistance of type 2 diabetes.

Beneficial effects of ginsenoside-Rg1 on ischemia-induced angiogenesis in diabetic mice

Neovascularization and the formation of collateral vessels are often impaired in diabetes mellitus (DM) population compared with non-diabetics. Alterations in vascular endothelial growth factor (VEGF) signaling and endothelial nitric oxide synthase (eNOS) dysfunction have been confirmed to play a crucial role in impaired neovascularization in diabetic mice. Accumulating data have suggested that Rg1, a main component of Panax ginseng, has the ability to promote tubulogenesis of human umbilical vein endothelial cells (HUVECs) in vitro, and that the mechanism involves increased expression level of VEGF as well as increased eNOS activation. Thus, we speculated that Rg1 might also have therapeutic effects on the impairment of neovascularization in diabetic individuals. The aim of the present study was to investigate whether Rg1 could improve angiogenesis in ischemic hindlimb of diabetic mice in vivo. Our data demonstrated that Rg1 treatment resulted in improved angiogenesis in the diabetic ischemic hindlimb, and the potential mechanism might involve increased eNOS activation, upregulated VEGF expression, and inhibited apoptosis. Our results suggest that Rg1 may be used as a novel and useful adjunctive drug for the therapy of peripheral arterial disease in DM.

The hypoglycemic effects of American red ginseng (Panax quinquefolius L.) on a diabetic mouse model

American ginseng (Panax quinquefolius L.) root health benefits include treatment of type 2 diabetes and this study evaluated the hypoglycemic effects of American red ginseng (ARG). ARG roots have increased bioactive phenolic contents, such as cinnamic acid and ferulic acid during the steaming process. The antihyperglycemic effects of methanol fraction extract of ARG, ferulic acid, and cinnamic acid were examined using a type 2 diabetic mouse model. The ARG treated group presented relatively lower blood glucose levels than the control group (P < 0.05). In addition, the glycogen and high density lipoprotein (HDL) contents were significantly increased while levels of plasma cholesterol and low density lipoprotein (LDL) concentration were significantly decreased in the ARG treated group. The groups treated with ferulic and cinnamic acids showed similar effects as those found in the ARG treated group. Thus, it is suggested that ARG roots, ferulic acid, and cinnamic acid have hypoglycemic effects in an animal model.

PRACTICAL APPLICATION

This study was conducted to elucidate the hypoglycemic effects of American red ginseng (ARG) using a type 2 diabetic mouse model. ARG showed an enhanced antioxidant capacity and higher antihyperglycemia effect. The glycogen and high density lipoprotein (HDL) contents were significantly increased while levels of plasma cholesterol and low density lipoprotein (LDL) concentration were significantly decreased in the ARG treated group. It is suggested that ARG has a potential to be used for human diabetic treatment.

Ginsenoside Re rapidly reverses insulin resistance in muscles of high-fat diet fed rats

OBJECTIVE

In a previous study, it was found that a ginseng berry extract with a high content of the ginsenoside Re normalized blood glucose in ob/ob mice. The objective of this study was to evaluate the effect of the ginsenoside Re on insulin resistance of glucose transport in muscles of rats made insulin resistant with a high-fat diet.

MATERIAL/METHOD

Rats were fed either rat chow or a high-fat diet for 5 weeks. The rats were then euthanized, and insulin stimulated glucose transport activity was measured in epitrochlearis and soleus muscle strips in vitro.

RESULTS

Treatment of muscles with Re alone had no effect on glucose transport. The high-fat diet resulted in ~50% decreases in insulin responsiveness of GLUT4 translocation to the cell surface and glucose transport in epitrochlearis and soleus muscles. Treatment of muscles with Re in vitro for 90 min completely reversed the high-fat diet-induced insulin resistance of glucose transport and GLUT4 translocation. This effect of Re is specific for insulin stimulated glucose transport, as Re treatment did not reverse the high-fat diet-induced resistance of skeletal muscle glucose transport to stimulation by contractions or hypoxia.

CONCLUSIONS

Our results show that the ginsenoside Re induces a remarkably rapid reversal of high-fat diet-induced insulin resistance of muscle glucose transport by reversing the impairment of insulin-stimulated GLUT4 translocation to the cell surface.

The effect of 12 weeks Anethum graveolens (dill) on metabolic markers in patients with metabolic syndrome; a randomized double blind controlled trial

BACKGROUND

The clustering of metabolic abnormalities defined as metabolic syndrome is now both a public health and a clinical problem .While interest in herbal medicine has greatly increased, lack of human evidence to support efficacies shown in animals does exist. This clinical trial study designed to investigate whether herbal medicine, Anethum graveolens (dill) extract, could improve metabolic components in patients with metabolic syndrome.

METHODS

A double-blind, randomized, placebo-controlled trial using a parallel design was conducted. 24 subjects who had metabolic syndrome diagnostic criteria (update of ATP III) were randomly assigned to either dill extract (n = 12) or placebo (n = 12) for 3 months.

RESULTS

Across lipid component of metabolic syndrome, no significant differences in triglyceride (TG) concentration and high density lipoprotein cholesterol were seen between the two groups. However TG improved significantly from baseline (257.0 vs. 201.5p = 0.01) with dill treatment but such a significant effect was not observed in placebo group. Moreover, no significant differences in waist circumference, blood pressure and fasting blood sugar were seen between two groups after 3 months follow up period.

CONCLUSION

In this small clinical trial in patients with metabolic syndrome, 12 weeks of dill extract treatment had a beneficial effect in terms of reducing TG from baseline. However dill treatment was not associated with a significant improvement in metabolic syndrome related markers compared to control group. Larger studies might be required to prove the efficacy and safety of long-term administration of dill to resolve metabolic syndrome components.

Steam-dried ginseng berry fermented with Lactobacillus plantarum controls the increase of blood glucose and body weight in type 2 obese diabetic db/db mice

This study examined whether steam-dried ginseng berries fermented with Lactobacillus plantarum (FSGB) could improve the indices of type 2 diabetes mellitus (T2DM) in obese db/db mice. FSGB was shown to have an effect on body weight and blood glucose/serum parameters when administered at a dose of 0.5 g/kg. In the intraperitoneal glucose tolerance test (IPGTT) and insulin tolerance test (ITT), FSGB was clearly shown to improve insulin tolerance and glucose tolerance. Moreover, FSGB was shown to enhance immune activities by increasing the immune cell population, and glucose transpoter 1 (GLUT1) mRNA expression in L6 cells was up-regulated, suggesting that FSGB can increase glucose transport activity in target cells. These results indicate that steam- and dry-processed ginseng berries fermented with L. plantarum can be used to effectively control blood sugar metabolism via improving insulin and glucose tolerance and body weight gain in db/db mice.

A pharmacological appraisal of medicinal plants with antidiabetic potential

Diabetes mellitus is a complicated metabolic disorder that has gravely troubled the human health and quality of life. Conventional agents are being used to control diabetes along with lifestyle management. However, they are not entirely effective and no one has ever been reported to have fully recovered from diabetes. Numerous medicinal plants have been used for the management of diabetes mellitus in various traditional systems of medicine worldwide as they are a great source of biological constituents and many of them are known to be effective against diabetes. Medicinal plants with antihyperglycemic activities are being more desired, owing to lesser side-effects and low cost. This review focuses on the various plants that have been reported to be effective in diabetes. A record of various medicinal plants with their established antidiabetic and other health benefits has been reported. These include Allium sativa, Eugenia jambolana, Panax ginseng, Gymnema sylvestre, Momrodica charantia, Ocimum sanctum, Phyllanthus amarus, Pterocarpus marsupium, Trigonella foenum graecum and Tinospora cordifolia. All of them have shown a certain degree of antidiabetic activity by different mechanisms of action.

Effect of diallyl trisulfide on the pharmacokinetics of dipyridamole in rats

This study was aimed to evaluate the effect of diallyl trisulfide (DATS), a major component derived from garlic used to inhibit platelet thromboxane formation, on the pharmacokinetics of dipyridamole. Pharmacokinetic parameters of dipyridamole were determined in rats following intragastric (80 mg/kg suspension or 40 mg/kg solution) or intravenous (3 mg/kg) administration of dipyridamole with coadministration (20 mg/kg) and long-term pretreatment of DATS (10 or 20 mg/kg/day for 15 consecutive days). In addition, everted gut sac models were used to assess transepithelial transport of dipyridamole and the effect of DATS on the intestinal absorption of dipyridamole. After coadministration and long-term pretreatment of DATS, significantly lower Cmax and AUC(0-24 h) were observed for intragastric administration of dipyridamole, whereas little change was noted after intravenous dipyridamole administration. After adding DATS (10 and 50 μg/mL) in the everted gut sacs, absorption of dipyridamole was remarkably decreased in the ileum and jejunum (p < 0.01). In conclusion, DATS reduced the oral exposure of dipyridamole in rats likely by the modification of the dissolution rate and intestinal absorption of dipyridamole, indicating that combined use of DATS or DATS-containing supplements with dipyridamole may require caution as low plasma concentrations of dipyridamole may lead to a subtherapeutic effect of this agent.

Ayurvedic medicine and anaesthesia

The use of herbal medicines has increased dramatically over the past few years. The United States alone noted a 380% increase in the consumption of these products. Although the common practice of taking over-the-counter herbal soups, herbal teas and other such prepacked preparations was not associated with adverse events at large, still, some herbs are known to cause problems, especially when large doses are taken. The American Society of Anaesthesiologist (ASA) has taken a conservative stance and recommended that it is prudent to stop these products at least 2–3 weeks prior to anaesthesia and surgery. This advice may be difficult to implement as most preoperative evaluations occur only a few days prior to surgery. Some of the Ayurvedic preparations have shown to improve the patient outcome when taken during the perioperative period. Hence, the conservative stance by ASA may not always benefit the patient. More scientific studies are needed to have more targeted recommendations. This article puts forward the facts that need to be addressed by researchers in the future.

Korean red ginseng (Panax ginseng C.A. Meyer) root fractions: differential effects on postprandial glycemia in healthy individuals

ETHNOPHARMACOLOGICAL RELEVANCE

Variations in ginsenoside profile may predict the postprandial glucose (PPG)-lowering efficacy of ginseng. Previously we reported differential PPG-lowering effects with two Korean red ginseng (KRG) root. FRACTIONS: body and rootlets, of variable ginsenoside profiles. Whether this effect is reproducible with a different KRG source is unclear. We therefore tested two root fractions from a KRG source with elevated ginsenoside levels to assess its effect on PPG.

MATERIALS AND METHODS

After a 12-h overnight fast, 13 healthy individuals (6M:7F; age=28 ± 10 y; BMI=24.1 ± 3 kg/m2; FBG=4.77 ± 0.04 mmol/L) randomly received either 3g of KRG-body, rootlets or placebo, on three separate visits. Treatments were consumed 60 min prior to a standard test meal with capillary blood samples at -60, 0, 15, 30, 45, 60, 90 and 120 min.

RESULTS

The KRGrootlets had>6 fold total ginsensosides than the KRG-body but did not significantly affect PPG. Despite a reduced ginsenoside profile, KRG-body lowered PPG levels at 45, 60, 90 and 120 min during the test (p<0.05), rendering an overall reduction of 27% in incremental area under the glucose curve compared to the control (p<0.05).

CONCLUSIONS

Comparing the results with a previously studied batch of KRG suggests a potential therapeutic dose range for ginsenosides. This observation should be clinically verified with acute screening and ginsenoside composition analysis.

Mechanism of action of natural products used in the treatment of diabetes mellitus

Diabetes mellitus (DM) is a metabolic disorder caused by insufficient or inefficient insulin secretary response and it is characterized by increased blood glucose levels (hyperglycemia). DM is a heterogonous group of syndromes. Glucose is the main energy source for the body, and in the case of DM, management of glucose becomes irregular. There are three key defects in the onset of hyperglycemia in DM, namely increased hepatic glucose production, diminished insulin secretion, and impaired insulin action. Conventional drugs treat diabetes by improving insulin sensitivity, increasing insulin production and/or decreasing the amount of glucose in blood. This article provides a comprehensive review of the mode of action of most popular hypoglycemic herbs, such as ginseng, bitter melon, fenugreek, banaba, Gymnema sylvestre and Coptis chinensis. The herbs act by increasing insulin secretion, enhancing glucose uptake by adipose and skeletal muscle tissues, inhibiting intestinal glucose absorption and inhibiting hepatic glucose production. Although evidence from animals and humans consistently supports the therapeutic effect of these phytomedicines, multicenter large-scale clinical trials have not been conducted to evaluate the safety and efficacy of these herbal medicines and their interaction with conventional drugs when administered simultaneously.

American ginseng stimulates insulin production and prevents apoptosis through regulation of uncoupling protein-2 in cultured beta cells

American ginseng root displays the ability to achieve glucose homeostasis both experimentally and clinically but the unknown mechanism used by ginseng to achieve its therapeutic effects on diabetes limits its application. Disruption in the insulin secretion of pancreatic β cells is considered the major cause of diabetes. A mitochondrial protein, uncoupling protein-2 (UCP-2) has been found to play a critical role in insulin synthesis and β cell survival. Our preliminary studies found that the extracts of American ginseng inhibit UCP-2 expression which may contribute to the ability of ginseng protecting β cell death and improving insulin synthesis. Therefore, we hypothesized that ginseng extracts suppress UCP-2 in the mitochondria of pancreatic β cells, promoting insulin synthesis and anti-apoptosis (a programmed cell-death mechanism). To test the hypothesis, the serum-deprived quiescent β cells were cultured with or without interleukin-1β (IL-1β), (200 pg ml⁻¹, a cytokine to induce β cell apoptosis) and water extracts of American ginseng (25 μg per 5 μl administered to wells of 0.5 ml culture) for 24 h. We evaluated effects of ginseng on UCP-2 expression, insulin production, anti-/pro-apoptotic factors Bcl-2/caspase-9 expression and cellular ATP levels. We found that ginseng suppresses UCP-2, down-regulates caspase-9 while increasing ATP and insulin production/secretion and up-regulates Bcl-2, reducing apoptosis. These findings suggest that stimulation of insulin production and prevention of β cell loss by American ginseng extracts can occur via the inhibition of mitochondrial UCP-2, resulting in increase in the ATP level and the anti-apoptotic factor Bcl-2, while down-regulation of pro-apoptotic factor caspase-9 occurs, lowering the occurrence of apoptosis, which support the hypothesis.

American ginseng improves neurocognitive function in senescence-accelerated mice: possible role of the upregulated insulin and choline acetyltransferase gene expression

AIM

To investigate the effects of American ginseng on neurocognitive function and glucose regulation in senescence-accelerated mice.

METHODS

Male senescence-resistant inbred strains (SAMR1) and senescence-prone inbred strains (SAMP10) mice were divided into five groups and fed either a control diet or an American ginseng-supplemented diet (1% or 2% g/g) from 6 weeks to 10 months of age. Bodyweight, levels of fasting plasma glucose (FPG) and grading scores were monitored every month and neurocognitive functions were evaluated at 9 months of age with a KUROBOX apparatus using a stress-free positive cue task. Gene expressions of peroxisome proliferator-activated receptor delta (PPAR-δ), insulin, choline acetyltransferase (ChAT) and amyloid precursor protein (APP) in the brain were measured by real-time quantitative reverse transcription polymerase chain reaction assays.

RESULTS

American ginseng decreased FPG in SAMR1 mice, but increased FPG in SAMP10 mice. Correct visit ratios were higher in both SAMR1 and SAMP10 strains consuming an American ginseng-supplemented diet. Gene upregulation of insulin and ChAT in the brain, but not of PPAR-δ or APP, was evident in American ginseng-fed groups.

CONCLUSION

Daily consumption of American ginseng induced an enhancement in neurocognitive function in senescence-accelerated mice, which could be related to the upregulation of insulin and ChAT gene expression in the brain. Geriatr Gerontol Int 2012; 12: 123-130.

Systematic review of randomized controlled trials evaluating the efficacy and safety of ginseng

This systematic review aims to evaluate the available evidence from randomized clinical trials of the clinical efficacy and safety of ginseng. Systematic literature searches were performed in 13 databases up to March 2009 without language restriction. All randomized clinical trials evaluating the clinical effects or safety of the use of ginseng monopreparations (Panax ginseng or P. quinquefolium) were considered for inclusion. A total of 411 potentially relevant studies were identified and 57 randomized clinical trials were included. The main indications included glucose metabolism, physical performance, psychomotor function, sexual function, cardiac function, pulmonary disease, and cerebrovascular disease. We found strong evidence of a positive effect of ginseng on glucose metabolism, psychomotor function, and pulmonary disease, whereas evidence suggests that ginseng is not effective at enhancing physical performance. However, ginseng generally has a good safety profile and the incidence of adverse effects seems to be low. In conclusion, our review compiles the evidence on the use of ginseng, finding a strong positive potential for glucose metabolism, psychomotor function, and pulmonary disease, but not for physical performance enhancement.

Ginsenosides from American ginseng: chemical and pharmacological diversity

Ginseng occupies a prominent position in the list of best-selling natural products in the world. Compared to the long history of use and widespread research on Asian ginseng, the study of American ginseng is relatively limited. In the past decade, some promising advances have been achieved in understanding the chemistry, pharmacology and structure-function relationship of American ginseng. To date, there is no systematic review of American ginseng. In this review, the different structures of the ginsenosides in American ginseng are described, including naturally occurring compounds and those resulting from steaming or biotransformation. Preclinical and clinical studies published in the past decade are also discussed. Highlighted are the chemical and pharmacological diversity and potential structural-activity relationship of ginsenosides. The goal is that this article is a useful reference to chemists and biologists researching American ginseng, and will open the door to agents in drug discovery.

Ginseng and ginsenoside Re do not improve β-cell function or insulin sensitivity in overweight and obese subjects with impaired glucose tolerance or diabetes

OBJECTIVE

Ginseng and its active component, ginsenoside Re, are popular herbal products that are advocated for treatment of diabetes. The purpose of this study was to determine whether ginseng or ginsenoside Re improves β-cell function and insulin sensitivity (IS) in insulin-resistant subjects.

RESEARCH DESIGN AND METHODS

Overweight or obese subjects (BMI = 34 ± 1 kg/m²) with impaired glucose tolerance or newly diagnosed type 2 diabetes were randomized to 30 days of treatment with ginseng root extract (8 g/day), ginsenoside Re (250-500 mg/day), or placebo. β-Cell function was assessed as the disposition index (DI) and measured by a frequently sampled oral glucose tolerance test, and IS was assessed as the relative increase in glucose disposal during a hyperinsulinemic-euglycemic clamp procedure plus stable isotope tracer infusion.

RESULTS

Values for DI and IS after therapy (Post) were not different from values before therapy (Pre) in the placebo (DI: Pre, 5.8 ± 0.9 × 10⁻³ and Post, 5.8 ± 0.8 × 10⁻³, P = 0.99; IS: Pre,165 ± 29% and Post, 185 ± 24%, P = 0.34), ginseng (DI: Pre, 7.7 ± 2.0 × 10⁻³ and Post, 6.0 ± 0.8 × 10⁻³, P = 0.29; IS: Pre, 171 ± 72% and Post,137 ± 59%, P = 0.88), and ginsenoside Re (DI: Pre, 7.4 ± 3.0 × 10⁻³ and Post, 5.9 ± 1.1 × 10⁻³, P = 0.50; IS: Pre, 117 ± 31% and Post, 134 ± 34%, P = 0.44) groups. Ginsenosides Re, Rb₁, and Rb₂ were not detectable in plasma after treatment with ginseng root extract or ginsenoside Re.

CONCLUSIONS

Oral ginseng or ginsenoside Re therapy does not improve β-cell function or IS in overweight/obese subjects with impaired glucose tolerance or newly diagnosed diabetes. Poor systemic bioavailability might be responsible for the absence of a therapeutic effect.