Protective effects of ethanolic extract of Zingiber officinale rhizome on the development of metabolic syndrome in high-fat diet-fed rats

Effects of Ginger (Zingiber officinale Roscoe) on Type 2 Diabetes Mellitus and Components of the Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

This article aims to assess the effects of ginger (Zingiber officinale Roscoe) on type 2 diabetes mellitus (T2DM) and/or components of the metabolic syndrome (MetS).

Methods

Electronic literature was searched in PubMed, Embase, the Cochrane Library, Chinese Biomedical Database, China National Knowledge Infrastructure, and Wanfang Database from inception of the database to May 19, 2017, and supplemented by browsing reference lists of potentially eligible articles. Randomized controlled trials on research subjects were included. Data were extracted as a mean difference (MD) and 95% confidence interval (CI). Subgroup analysis of fasting blood glucose (FBG) was performed.

Results

10 studies met the inclusion criteria with a total of 490 individuals. Ginger showed a significant beneficial effect in glucose control and insulin sensitivity. The pooled weighted MD of glycosylated hemoglobin (HbA1c) was −1.00, (95% CI: −1.56, −0.44; P < 0.001). Subgroup analysis revealed that ginger obviously reduced FBG in T2DM patients (−21.24; 95% CI: −33.21, −9.26; P < 0.001). Meanwhile, the significant effects of improvement of lipid profile were observed. Most analyses were not statistically heterogeneous.

Conclusion

Based on the negligible side effects and obvious ameliorative effects on glucose control, insulin sensitivity, and lipid profile, ginger may be a promising adjuvant therapy for T2DM and MetS.

Glucuronidation of [6]-shogaol, [8]-shogaol and [10]-shogaol by human tissues and expressed UGT enzymes: identification of UGT2B7 as the major contributor

Shogaols, mainly [6]-shogaol (6S), [8]-shogaol (8S) and [10]-shogaol (10S), the predominant and characteristic pungent phytochemicals in ginger, are responsible for most of its beneficial effects. However, poor oral bioavailability owing to extensive glucuronidation limits their application. The present study aimed to characterize the glucuronidation pathways of 6S, 8S and 10S by using pooled human liver microsomes (HLM), human intestine microsomes (HIM) and recombinant human UDP-glucosyltransferases (UGTs). The rates of glucuronidation were determined by incubating shogaols with uridine diphosphate glucuronic acid-supplemented microsomes. Kinetic parameters were derived by appropriate model fitting. Reaction phenotyping assays, activity correlation analyses and relative activity factors were performed to identify the main UGT isoforms. As a result, one mono-4′-O-glucuronide was detected after incubating each shogaol with HLM and HIM. Enzymes kinetic analysis demonstrated that glucuronidation of shogaols consistently displayed the substrate inhibition profile, and the liver showed higher metabolic activity for shogaols (CL_int = 1.37–2.87 mL min⁻¹ mg⁻¹) than the intestine (CL_int = 0.67–0.85 mL min⁻¹ mg⁻¹). Besides, reaction phenotyping assays revealed that UGT2B7 displayed the highest catalytic ability (CL_int = 0.47–1.17 mL min⁻¹ mg⁻¹) among all tested UGTs. In addition, glucuronidation of shogaols was strongly correlated with AZT glucuronidation (r = 0.886, 0.803 and 0.871 for glucuronidation of 6S, 8S and 10S, respectively; p < 0.01) in a bank of individual HLMs (n = 9). Furthermore, UGT2B7 contributed to 40.8%, 34.2% and 36.0% for the glucuronidation of 6S, 8S and 10S in HLM, respectively. Taken altogether, shogaols were efficiently metabolized through the glucuronidation pathway, and UGT2B7 was the main contributor to their glucuronidation.

The glucuronidation pathways of shogaols ([6]-shogaol, [8]-shogaol and [10]-shogaol) were characterized in human tissues and recombinant human UDP-glucosyltransferases, and UGT2B7 was identified as the main contributor to their glucuronidation.

The Effects of Ginger on Fasting Blood Sugar, Hemoglobin A1c, and Lipid Profiles in Patients with Type 2 Diabetes

BACKGROUND

Lipid and glycemic abnormalities are prevalent in diabetes leading to long term complications. Use of safe and natural foods instead of medications is now considered by many scientists.

OBJECTIVES

This study aimed at determining the effect of ginger on lipid and glucose levels of patients with type 2 diabetes mellitus.

METHODS

In a double-blind placebo-controlled trial, 50 patients with type 2 diabetes were randomly allocated to 2 groups of intervention (n = 25) and placebo (n = 25). Each patient received 2000 mg per day of ginger supplements or placebo for 10 weeks. Serum levels of fasting blood sugar (FBS), total cholesterol (TC), triacylglycerol (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and glycosylated hemoglobin (HbA1C) were analyzed. Daily dietary intakes and anthropometric parameters were also determined.

RESULTS

Data from 45 patients were analyzed (23 patients in the ginger group and 22 patients in the control group) at the end of the study. Ginger consumption significantly reduced serum levels of fasting blood glucose (-26.30 ± 35.27 vs. 11.91 ± 38.58 mg/dl; P = 0.001) and hemoglobin A1C (-0.38 ± 0.35 vs. 0.22 ± 0.29 %; P < 0.0001) compared to the placebo group. Ginger consumption also reduced the ratio of LDL-C/HDL-C (2.64 ± 0.85 vs. 2.35 ± 0.8; P = 0.009). However, there was no significant change in serum concentrations of triglycerides, total cholesterol, LDL-C, and HDL-C due to the ginger supplements.

CONCLUSIONS

The current results showed that ginger could reduce serum levels of fasting blood glucose and hemoglobin A1C in patients with diabetes.

Saponins as adipokines modulator: A possible therapeutic intervention for type 2 diabetes

Development of type 2 diabetes has been linked to β-cell failure coupled with insulin resistance and obesity. Adipose tissue, known as the fat store, secretes a number of hormones and proteins collectively termed adipokines some of which regulate insulin sensitivity. Dysregulation in the secretion of adipokines has been linked to insulin resistance and type 2 diabetes. In this review, we summarized evidence of the role of adipokines with focus on leptin, adiponectin, adipsin, visfatin and apelin in the pathogenesis of type 2 diabetes and discussed the potential of saponins to modify the ill-regulated adipokines secretions, which could promote the use of this class of phytochemicals as potential antidiabetics agents.

Beneficial effects of ginger Zingiber officinale Roscoe on obesity and metabolic syndrome: a review

In recent years, metabolic syndromes (MetSs), including diabetes mellitus, dyslipidemia, and cardiovascular diseases, have become a common health problem in both developed and developing countries. Accumulating data have suggested that traditional herbs might be able to provide a wide range of remedies in prevention and treatment of MetSs. Ginger (Zingiber officinale Roscoe, Zingiberaceae) has been documented to ameliorate hyperlipidemia, hyperglycemia, oxidative stress, and inflammation. These beneficial effects are mediated by transcription factors, such as peroxisome proliferator-activated receptors, adenosine monophosphate-activated protein kinase, and nuclear factor κB. This review focuses on recent findings regarding the beneficial effects of ginger on obesity and related complications in MetS and discusses its potential mechanisms of action. This review provides guidance for further applications of ginger for personalized nutrition and medicine.

Ginger Treatment Ameliorates Alcohol-induced Myocardial Damage by Suppression of Hyperlipidemia and Cardiac Biomarkers in Rats

Background:

Alcohol-induced hyperlipidemia is positively correlated with cardiovascular diseases. Several herbal extracts have been reported to protect the cardiac injury and suppress the hyperlipidemia. However, the effect of ginger extracts on alcohol-induced hyperlipidemia and associated myocardial damage remains unclear.

Objective:

This study investigated the cardio-protective properties of ginger ethanolic extract (Gt) against alcohol-induced myocardial damage, and further distinguished the association between hyperlipidemia and occurrence of myocardial damage in rats.

Materials and Methods:

Twenty four Wistar male albino rats (250 ± 20 g) were divided into four groups including, Normal control (NC) (0.9% NaCl), Ginger treated (Gt) (200 mg/Kg b.w.), Alcohol treated (At) (20% of 6g/kg b.w. alcohol), and Alcohol along with Ginger treatment (At+Gt). In this study, lipid profiles such as fatty acids, triglycerides, total cholesterol, phospholipids, low density lipoprotein and high density lipoproteins, and cardiac biomarkers, including LDH, AST, CK-MB, cTn-T and cTn-I were examined in rats. Furthermore, histopathological studies were also conducted.

Results:

We found that alcohol-induced myocardial damage was associated with increased lipid profile except high density lipoprotein in alcohol treated (20%, 6g/kg b.w.) rats compared with control. Ginger treatment significantly reduced the alcohol-induced lipid profiles except high density lipoproteins. Furthermore, elevated cardiac biomarkers activity with alcohol intoxication was substantially suppressed by ginger treatment. In addition, ginger treatment for 7-weeks significantly minimized the alcohol-induced myocardial damage.

Conclusion:

Our results concluded that ginger could protect alcohol-induced myocardial damage by suppression of hyperlipidemia and cardiac biomarkers.

SUMMARY

Ginger extract could alleviate the myocardial injury partially due to the suppression of circulating FFAs and TG levels.

Increased circulating cholesterol, LDL and phospholipids with alcohol intake were substantially suppressed by ginger treatment

Alcohol, induced an increase in cardiac damage biomarkers, CK-MB, cTn-T and cTn-I were remarkably suppressed by ginger treatment

Performed histopathological studies by transmission electron microscopy and light microscopy shows additional convincing evidence on ginger cardio-protective effects. The drastic changes were rehabilitated in cardiac tissue by ginger treatment may be it acts as a good antioxidant and possessing hypolipidemic activity.

Collectively, our findings confirm hypothesis that ginger has cardio protective potential through suppression of hyperlipidemia, preserving the tissue damage bio markers, cardiac biomarkers in plasma and preservation of histoarchitecture of myocytes.

Abbreviations used: Gt: Ginger Ethanolic Extract; NC: Normal Control; At: Alcohol treated; MI: Myocardial Infarction

Evaluation of daily ginger consumption for the prevention of chronic diseases in adults: A cross-sectional study

OBJECTIVES

The aim of this study was to assess daily ginger consumption and explore its correlation with chronic diseases among adults and to analyze further how different levels of ginger intake affect the prevalence of chronic diseases.

METHODS

We examined the prevalence rate of chronic diseases (diabetes, hypertension, coronary heart disease [CHD], hyperlipidemia, cerebrovascular disease, fatty liver, anemia, and tumor), as well as the daily ginger intake in a large cross-sectional study. In all, 4628 participants (1823 men and 2805 women) ages 18 to 77 y completed face-to-face dietary and health questionnaires. We extracted diagnoses and investigation results from the participants' health records. The association between the level of ginger intake (0-2 g/d, 2-4 g/d, and 4-6 g/d) and the prevalence of chronic diseases was analyzed by using χ2 statistical test and unconditional logistic model.

RESULTS

Overall, daily ginger consumption was associated with decreased risk for hypertension (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.86-0.98) and CHD (OR, 0.87; 95% CI, 0.78-0.96) in adults ages ≥18 y. Differences were also observed in adults ages ≥40 y: hypertension (OR, 0.92; 95% CI, 0.87-0.99), CHD (OR, 0.87; 95% CI, 0.78-0.97). However, after 20 y, no association was seen for hypertension but there was still a difference between ginger consumption and CHD in adults ages ≥60 y (OR, 0.84; 95% CI, 0.73-0.96). Again, the probability of illness (hypertension or CHD) decreased when the level of daily ginger intake increased.

CONCLUSIONS

These data indicate that ginger has a potential preventive property against some chronic diseases, especially hypertension and CHD, as well as its ability to reduce the probability of illness.

A systems perspective on brown adipogenesis and metabolic activation

Brown adipocytes regulate energy expenditure via mitochondrial uncoupling. This makes these fat cells attractive therapeutic targets to tackle the burgeoning issue of obesity, which itself is coupled to insulin resistance, type 2 diabetes, cardiovascular and fatty liver disease. Recent research has revealed a complex network underlying brown fat cell differentiation and thermogenic activation, involving secreted factors, signal transduction, metabolic pathways and gene regulatory components. Given that brown fat is now reported to be present in adult humans, it is desirable to harness the knowledge from each network module to design effective therapeutic strategies. In this review, we will present a systems perspective on brown adipogenesis and the subsequent metabolic activation of brown adipocytes by integrating signaling, metabolic and gene regulatory modules with a specific focus on known 'druggable' targets within each module.

Molecular factors involved in the hypolipidemic- and insulin-sensitizing effects of a ginger (Zingiber officinale Roscoe) extract in rats fed a high-fat diet

Hypolipidemic and hypoglycemic properties of ginger in animal models have been reported. However, information related to the mechanisms and factors involved in the metabolic effects of ginger at a hepatic level are limited. The aim of the present study was to investigate molecular factors involved in the hypoglycemic and hypolipidemic effects of a hydroethanolic ginger extract (GE) in the liver of rats fed a high-fat diet (HFD). The study was conducted in male Wistar rats divided into the following 3 groups: (i) Rats fed a standard diet (3.5% fat), the control group; (ii) rats fed an HFD (33.5% fat); and (iii) rats fed an HFD treated with GE (250 mg·kg-1·day-1) for 5 weeks (HFD+GE). Plasma levels of glucose, insulin, lipid profile, leptin, and adiponectin were measured. Liver expression of glycerol phosphate acyltransferase (GPAT), cholesterol 7 alpha-hydroxylase, peroxisome proliferator-activated receptors (PPAR), PPARα and PPARγ, glucose transporter 2 (GLUT-2), liver X receptor, sterol regulatory element-binding protein (SREBP1c), connective tissue growth factor (CTGF), and collagen I was measured. Data were analyzed using a 1-way ANOVA, followed by a Newman-Keuls test if differences were noted. The study showed that GE improved lipid profile and attenuated the increase of plasma levels of glucose, insulin, and leptin in HFD rats. This effect was associated with a higher liver expression of PPARα, PPARγ, and GLUT-2 and an enhancement of plasma adiponectin levels. Furthermore, GE reduced liver expression of GPAT, SREBP1c, CTGF, and collagen I. The results suggest that GE might be considered as an alternative therapeutic strategy in the management of overweight and hepatic and metabolic-related alterations.

The effect of ginger supplementation on serum C-reactive protein, lipid profile and glycaemia: a systematic review and meta-analysis

Aim

To undertake a systematic review and meta-analysis of prospective studies to determine the effect of ginger supplementation on serum C-reactive protein (CRP), lipid profile, and glycaemia.

Method

PubMed-MEDLINE, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until July 2016) to identify prospective studies evaluating the impact of ginger supplementation on serum CRP. Random-effects model meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I² index. Systematic review registration: CRD42016035973.

Results

From a total of 265 entries identified via searches, 9 studies were included in the final selection. The meta-analysis indicated a significant reduction in serum CRP concentrations following ginger supplementation [weighted mean difference (WMD)−0.84 mg/L (95% CI −1.38 to −0.31, I² 56.3%)]. The WMD for fasting blood glucose and HbA1c was −1.35 mg/dl (95% CI −2.04 to −0.58, I² 12.1%) and −1.01 (95% CI −1.28 to −0.72, I² 9.4%), respectively. Moreover, high-density lipoprotein and triglyceride significantly improved after ginger administration [1.16 mg/dl (95% CI 0.52 to 1.08, I² 12.3%) and −1.63 mg/dl (95% CI −3.10 to −0.17, I² 8.1%), respectively]. These findings were robust in sensitivity analyses. Random-effects meta-regression revealed that changes in serum CRP levels were independent of the dosage of ginger supplementation (slope −0.20; 95% CI −0.95 to 0.55; p=0.60).

Conclusions

This meta-analysis suggests that ginger supplementation significantly reduces serum CRP and improves glycaemia indexes and lipid profile. Randomized control trials with larger sample size and with a longer-term follow-up period should be considered for future investigations.

Bioactive compounds isolated from apple, tea, and ginger protect against dicarbonyl induced stress in cultured human retinal epithelial cells

BACKGROUND

Methylglyoxal (MGO) is known to be a major precursor of advanced glycation end products (AGEs) which are linked to diabetes and its related complications. Naturally occurring bioactive compounds could play an important role in countering AGEs thereby minimizing the risk associated with their formation.

METHODS

In this study, eight specific bioactive compounds isolated from apple, tea and ginger were evaluated for their AGEs scavenging activity using Human Retinal Pigment Epithelial (H-RPE) cells treated with MGO.

RESULTS

Among the eight specific compounds evaluated, (-)-epigallocatechin 3-gallate (EGCG) from tea, phloretin in apple, and [6]-shogaol and [6]-gingerol from ginger were found to be most effective in preventing MGO-induced cytotoxicity in the epithelial cells. Investigation of possible underlying mechanisms suggests that that these compounds could act by modulating key regulative detoxifying enzymes via modifying nuclear factor-erythroid 2-related factor 2 (Nrf2) function. MGO-induced cytotoxicity led to increased levels of AGEs causing increase in Nε-(Carboxymethyl) lysine (CML) and glutathione (GSH) levels and over expression of receptor for advanced glycation end products (RAGE). Data also showed that translocation of Nrf2 from cytosol to nucleus was inhibited, which decreased the expression of detoxifying enzyme like heme oxygenase-1 (HO-1). The most potent bioactive compounds scavenged dicarbonyl compounds, inhibited AGEs formation and significantly reduced carbonyl stress by Nrf2 related pathway and restoration of HO-1 expression.

CONCLUSIONS

These findings demonstrated the protective effect of bioactive compounds derived from food sources against MGO-induced carbonyl stress through activation of the Nrf2 related defense pathway, which is of significant importance for therapeutic interventions in complementary treatment/management of diabetes-related complications.

[6]-Gingerol Affects Glucose Metabolism by Dual Regulation via the AMPKα2-Mediated AS160-Rab5 Pathway and AMPK-Mediated Insulin Sensitizing Effects

[6]-Gingerol has been used to control diabetes and dyslipidemia; however, its metabolic role is poorly understood. In this study, [6]-gingerol increased adenosine monophosphate (AMP)-activated protein kinase (AMPK) phosphorylation in mouse skeletal muscle C2C12 cells. Stimulation of glucose uptake by [6]-gingerol was dependent on AMPKα2. Moreover, both Inhibition and knockdown of AMPKα2 blocked [6]-gingerol-induced glucose uptake. [6]-Gingerol significantly decreased the activity of protein phosphatase 2A (PP2A). Inhibition of PP2A activity with okadaic acid enhanced the phosphorylation of AMPKα2. Moreover, the interaction between AMPKα2 and PP2A was increased by [6]-gingerol, suggesting that PP2A mediates the effect of [6]-gingerol on AMPK phosphorylation. In addition, [6]-gingerol increased the phosphorylation of Akt-substrate 160 (AS160), which is a Rab GTPase-activating protein. Inhibition of AMPKα2 blocked [6]-gingerol-induced AS160 phosphorylation. [6]-gingerol increased the Rab5, and AMPKα2 knockdown blocked [6]-gingerol-induced expression of Rab5, indicating AMPK play as an upstream of Rab5. It also increased glucose transporter 4 (GLUT4) mRNA and protein expression and stimulated GLUT4 translocation. Furthermore, insulin-mediated glucose uptake and Akt phosphorylation were further potentiated by [6]-gingerol treatment. This potentiation was not observed in the presence of AMPK inhibitor compound C. In summary, our results suggest that [6]-gingerol plays an important role in glucose metabolism via the AMPKα2-mediated AS160-Rab5 pathway and through potentiation of insulin-mediated glucose regulation.

Individually and Combined Water-Based Exercise With Ginger Supplement, on Systemic Inflammation and Metabolic Syndrome Indices, Among the Obese Women With Breast Neoplasms

BACKGROUND

Breast neoplasms has known as the most common cancer among the women worldwide, and relationship between obesity, metabolic syndrome, inflammation and cancer has been recognized since many years ago.

OBJECTIVES

The aim of this study was to determine the individual and concomitant effect of 6-weeks water-based exercise and oral ginger supplement on markers that have related to metabolic syndrome and systemic inflammation in obese women with breast neoplasms.

PATIENTS AND METHODS

Forty women whose have diagnosed with breast neoplasms have volunteered to participate in the study. Subjects have randomly assigned into four groups; placebo, exercise training, ginger supplement and exercise training+ ginger supplement groups. Subjects in the ginger supplement group and the exercise training+ ginger supplement group have orally received 4 capsules, 7 days a week and for 6 weeks. The water-based exercise training program have collected at a progressive intensity and time, have ranged from 50% to 75% of heart rate reserve, in a pool, 4 times a week for 6 weeks. Fasting blood sampling has collected at the pretest and post-test.

RESULTS

The ginger supplementation and the water-base exercise have resulted in a reduction of hs-CRP, IL-10, insulin, glucose, insulin resistance, LDL-C, TG; but an increase in HDL-C and HDL-C/LDL-C. The water-base exercise and ginger supplement group have significantly shown larger positive effect in all outcomes, in comparison with the water-base exercise or ginger supplement alone groups.

CONCLUSIONS

Findings have suggested that obese breast neoplasms survivors have commonly shown metabolic syndrome and elevated inflammation, which placed them at an increased risk for cardiovascular diseases. Moreover, data has indicated a protective effect of the nondrug strategies, such as water-base exercise and ginger supplementation have played an important role in pathogenesis of inflammatory and metabolic responses, among diagnosed breast neoplasms.

Traditional Korean Herbal Formula Samsoeum Attenuates Adipogenesis by Regulating the Phosphorylation of ERK1/2 in 3T3-L1 Cells

Adipogenesis is the cell differentiation process from preadipocytes into adipocytes and the critical action in the development of obesity. In the present study, we conducted in vitro analyses to investigate the inhibitory effects of Samsoeum (SSE), a traditional herbal decoction. SSE had no significant cytotoxic effect against either the undifferentiated or differentiated 3T3-L1 cells. Oil Red O staining results showed that SSE significantly inhibited fat accumulation in adipocytes. SSE treatment consistently reduced the intracellular triglyceride content in the cells. SSE significantly inactivated glycerol-3-phosphate dehydrogenase (GPDH), a major link between carbohydrate and lipid metabolisms in 3T3-L1 adipocytes, and markedly inhibited the production of leptin, an important adipokine, in differentiated cells. SSE markedly suppressed the mRNA expression of the adipogenesis-related genes peroxisome proliferator-activated receptor-gamma (PPAR-γ), CCAAT/enhancer binding protein-alpha (C/EBP-α), fatty acid synthase (FAS), lipoprotein lipase (LPL), and fatty acid binding protein 4 (FABP4). Importantly, SSE increased the phosphorylation of ERK1/2, but not p38 MAPK and JNK, in adipose cells. Overall, our results indicate that SSE exerts antiadipogenic activity and modulates expressions of adipogenesis-related genes and ERK1/2 activation in adipocytes.

Antihypercholesterolemic and antioxidant efficacies of zerumbone on the formation, development, and establishment of atherosclerosis in cholesterol-fed rabbits

Owing to the high incidence of cholesterol-induced cardiovascular disease, particularly atherosclerosis, the current study was designed to investigate the preventive and therapeutic efficacies of dietary zerumbone (ZER) supplementation on the formation and development of atherosclerosis in rabbits fed with a high cholesterol diet. A total of 72 New Zealand white rabbits were divided randomly on two experimental studies carried out 8 weeks apart. The first experiment was designed to investigate the prophylactic efficacy of ZER in preventing early developed atheromatous lesion. The second experimental trial was aimed at investigating the therapeutic effect of ZER in reducing the atherosclerotic lesion progression and establishment. Sudanophilia, histopathological, and ultrastructural changes showed pronounced reduction in the plaque size in ZER-medicated aortas. On the other hand, dietary supplementation of ZER for almost 10 weeks as a prophylactic measure indicated substantially decreasing lipid profile values, and similarly, plaque size in comparison with high-cholesterol non-supplemented rabbits. Furthermore, the results of oxidative stress and antioxidant biomarker evaluation indicated that ZER is a potent antioxidant in suppressing the generation of free radicals in terms of atherosclerosis prevention and treatment. ZER significantly reduced the value of malondialdehyde and augmented the value of superoxide dismutase. In conclusion, our data indicated that dietary supplementation of ZER at doses of 8, 16, and 20 mg/kg alone as a prophylactic measure, and as a supplementary treatment with simvastatin, significantly reduced early plague formation, development, and establishment via significant reduction in serum lipid profile, together with suppression of oxidative damage, and therefore alleviated atherosclerosis lesions.

The effect of ginger (Zingiber officinale) on glycemic markers in patients with type 2 diabetes

BACKGROUND

Ginger (Zingiber officinale) is one of the functional foods which contains biological compounds including gingerol, shogaol, paradol and zingerone. Ginger has been proposed to have anti-cancer, anti-thrombotic, anti-inflammatory, anti-arthritic, hypolipidemic and analgesic properties. Here, we report the effect of ginger supplementation on glycemic indices in Iranian patients with type 2 diabetes.

METHODS

A double-blind, placebo-controlled, randomized clinical trial was conducted on 20-60 -year-old patients with type 2 diabetes who did not receive insulin. Participants in the intervention and control groups were received 3 g of powdered ginger or placebo (lactose) (in capsules) daily for 3 months. Glycemic indices, total antioxidant capacity (TAC), malondialdehyde (MDA), C-reactive protein (CRP), serum paraoxonase, dietary intake and physical activity were measured at the beginning and end of the study, and after 12 h fasting.

RESULTS

Comparison of the indices after 3 months showed that the differences between the ginger and placebo groups were statistically significant as follows: serum glucose (-19.41 ± 18.83 vs. 1.63 ± 4.28 mg/dL, p < 0.001), HbA1c percentage (-0.77 ± 0.88 vs. 0.02 ± 0.16%, p < 0.001), insulin (-1.46 ± 1.7 vs. 0.09 ± 0.34 μIU/mL, p < 0.001), insulin resistance (-16.38 ± 19.2 vs. 0.68 ± 2.7, p < 0.001), high-sensitive CRP (-2.78 ± 4.07 vs. 0.2 ± 0.77 mg/L, p < 0.001), paraoxonase-1 (PON-1) (22.04 ± 24.53 vs. 1.71 ± 2.72 U/L, p < 0.006), TAC (0.78 ± 0.71 vs. -0.04 ± 0.29 µIU/mL, p < 0.01) and MDA (-0.85 ± 1.08 vs. 0.06 ± 0.08 µmol/L, p < 0.001) were significantly different.

CONCLUSIONS

This report shows that the 3 months supplementation of ginger improved glycemic indices, TAC and PON-1 activity in patients with type 2 diabetes.

Effects of ginger on serum glucose, advanced glycation end products, and inflammation in peritoneal dialysis patients

OBJECTIVE

The aim of this study was to investigate the effects of ginger supplementation on serum glucose, advanced glycation end products, oxidative stress, and systemic and vascular inflammatory markers in patients on peritoneal dialysis (PD).

METHODS

In this randomized, double-blind, placebo-controlled trial, 36 patients on PD were randomly assigned to either the ginger or the placebo group. The patients in the ginger group received 1000 mg/d ginger for 10 wk, whereas the placebo group received corresponding placebos. At baseline and the end of week 10, serum concentrations of glucose, carboxymethyl lysine, pentosidine, malondialdehyde (MDA), high-sensitivity C-reactive protein (hs-CRP), soluble intercellular adhesion molecule type 1 (sICAM-1), soluble vascular cell adhesion molecule type 1 (sVCAM-1), and sE-selectin were measured after a 12- to 14-h fast.

RESULTS

Serum fasting glucose decreased significantly up to 20% in the ginger group at the end of week 10 compared with baseline (P < 0.05), and the reduction was significant in comparison with the placebo group (P < 0.05). There were no significant differences between the two groups in mean changes of serum carboxymethyl lysine, pentosidine, MDA, hs-CRP, sICAM-1, sVCAM-1, and sE-selectin.

CONCLUSION

This study indicated that daily administration of 1000 mg ginger reduces serum fasting glucose, which is a risk factor for hyperinsulinemia, dyslipidemia, peritoneal membrane fibrosis, and cardiovascular disease, in patients on PD.

Hepatoprotective effect of herb formula KIOM2012H against nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a hepatic ailment with a rapidly increasing incidence due to dietary hypernutrition and subsequent obesity. Fatty liver disease can lead to steatohepatitis, fibrosis, cirrhosis, and even cancer, which is associated with various complications. Discovering effective natural materials and herbs can provide alternative and complementary medical treatments to current chemical pharmaceuticals. To develop an effective natural agent for NAFLD, we formulated a combination of four herb mixtures (KIOM2012H) and observed lipid-lowering efficacy. The inhibitory effects of KIOM2012H on free fatty acid-induced lipid accumulation, triglyceride contents, and gene expressions were analyzed in HepG2 cells. Using high fat diet-fed mice, body weight changes, gross liver appearances, hepatic triglyceride contents, and gene expressions were evaluated. KIOM2012H dose-dependently inhibited lipid accumulation and gene expressions involved in lipogenesis and related regulators. Experimental animals also showed a decrease in body weight changes and lipid-associated physiological parameters. This study shows that KIOM2012H has an alleviating effect on fatty acid and lipid accumulation, and therefore can be applied for development of new therapeutic pharmaceuticals for treatment of NAFLD using natural products and herbs.

Some pharmacological effects of cinnamon and ginger herbs in obese diabetic rats

AIMS

The present study was designed to assess some pharmacological effects of cinnamon (CAE) and ginger (GAE) aqueous extracts in obese diabetic rats, and to elucidate the potential mechanisms.

MATERIALS AND METHODS

Forty-two Sprague-Dawley rats were randomized into 6 equal groups. Group 1 was a negative control and the other groups were rendered obese by feeding rats on high-fat diet for 4 weeks. The obese rats were subcutaneously injected with alloxan for 5*days to induce diabetes. Group 2 was a positive control, and Groups 3, 4, 5 and 6 were orally given CAE in doses 200 and 400 mg/kg and GAE in the same doses, respectively for 6 weeks. Blood samples were collected for serum biochemical analyses. Kidneys were dissected out to assay activity of tissue antioxidant enzymes: Superoxide dismutase, glutathione peroxidase and catalase.

RESULTS

CAE and GAE significantly reduced body weight and body fat mass; normalized serum levels of liver enzymes; improved lipid profile; decreased blood glucose and leptin and increased insulin serum levels in obese diabetic rats. Both extracts also increased activity of kidney antioxidant enzymes.

CONCLUSION

CAE and GAE exhibit anti-obesity, hepatoprotective, hypolipidemic, antidiabetic and anti-oxidant effects in obese diabetic rats. These results confirm the previous reports on both extracts. The potential mechanisms underlying these effects are fully discussed and clarified. Our results affirm the traditional use of cinnamon and ginger for treating patients suffering from obesity and diabetes. The obese diabetic rat model used in this study is a novel animal model used in pharmacology researches.

Zingiber officinale (Ginger): A Future Outlook on Its Potential in Prevention and Treatment of Diabetes and Prediabetic States

Diabetes is reaching pandemic levels in both developing and developed countries and requires safe, affordable, and effective therapies. This report summarises work in our laboratory on the effects of Zingiber officinale (ginger) and its components in diabetes models and provides a future outlook on the potential for their use in type 2 diabetes. A high fat diet rat model showed modulation of body weight gain and normalisation of glucose and lipid metabolic disturbances, with reduction of insulin resistance in a high fat-high carbohydrate diet model. Ginger extract inhibits enhanced NF-κB in liver of high fat-fed rats through inhibition of the IKK/IκBα/NF-κB classical pathway. The major active component (S)-[6]-gingerol inhibited elevated cytokines in inflamed HuH7 cells through suppression of COX2 expression and protection against the ROS pathway. Ginger extract and gingerols enhanced glucose uptake in L6 myotubes, by enhancing translocation of GLUT4 to the surface membrane and activation of AMPKα1 through a Ca2+/calmodulin-dependent protein kinase kinase pathway. (S)-[6]-Gingerol also enhanced energy metabolism through marked increment of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) gene expression and mitochondrial content in L6 skeletal muscle cells. Future studies will require well designed clinical trials on ginger preparations of defined chemical composition.

Preventative effect of Zingiber officinale on insulin resistance in a high-fat high-carbohydrate diet-fed rat model and its mechanism of action

Insulin resistance is a core component of metabolic syndrome and usually precedes the development of type 2 diabetes mellitus. We have examined the preventative effect of an ethanol extract of ginger (Zingiber officinale, Zingiberaceae) on insulin resistance in a high-fat high-carbohydrate (HFHC) diet-fed rat model of metabolic syndrome. The HFHC control rats displayed severe insulin resistance, whilst rats treated with ginger extract (200 mg/kg) during HFHC diet feeding showed a significant improvement of insulin sensitivity using the homeostatic model assessment of insulin resistance (HOMA-IR) after 10 weeks (p < 0.01). An in vitro mechanistic study showed that (S)-[6]-gingerol, the major pungent phenolic principle in ginger, dose-dependently (from 50 to 150 μM) increased AMPK α-subunit phosphorylation in L6 skeletal muscle cells. This was accompanied by a time-dependent marked increment of PGC-1α mRNA expression and mitochondrial content in L6 skeletal muscle cells. These results suggest that the protection from HFHC diet-induced insulin resistance by ginger is likely associated with the increased capacity of energy metabolism by its major active component (S)-[6]-gingerol.

Herbal medicines for the treatment of nonalcoholic steatohepatitis: current scenario and future prospects

Nonalcoholic steatohepatitis (NASH) is a multifactorial disease and has close correlations with other metabolic disorders. This makes its treatment difficult using a single pharmacological drug. Use of plant extract/decoction or polyherbal formulation to treat various liver diseases is very well mentioned in various traditional systems of medicine (Ayurveda, Japanese or traditional Chinese Medicine, and Kampo medicine). Medicinal herbs are known for their multifaceted implications and thus can form an effective treatment schedule against NASH. Till date, several plant extracts, polyherbal formulations, and phytochemicals have been evaluated for their possible therapeutic potential in preventing onset and progression of NASH in experimental models, but clinical studies using the same are sparse. Herbal extracts with antioxidants, antidiabetic, and antihyperlipidemic properties have been shown to ameliorate symptoms of NASH. This review article is a meticulous compilation of our current knowledge on the role of natural products in alleviating NASH and possible lacunae in research that needs to be addressed.

The effect of ginger consumption on glycemic status, lipid profile and some inflammatory markers in patients with type 2 diabetes mellitus

OBJECTIVE

To assess the effect of ginger consumption on glycemic status, lipid profile and some inflammatory markers in patients with type 2 diabetes mellitus.

METHODS

In a double-blinded, placebo-controlled clinical trial, 70 type 2 diabetic patients were enrolled. They allocated randomly into ginger group and control group. They consumed 1600 mg ginger versus 1600 mg wheat flour placebo daily for 12 weeks. Serum sugar, lipids, CRP, PGE2 and TNFα were measured before and after intervention.

RESULTS

Ginger reduced fasting plasma glucose, HbA1C, insulin, HOMA, triglyceride, total cholesterol, CRP and PGE₂ significantly compared with placebo group (p < 0.05). There were no significant differences in HDL, LDL and TNFα between two groups (p > 0.05).

CONCLUSION

Ginger improved insulin sensitivity and some fractions of lipid profile, and reduced CRP and PGE₂ in type 2 diabetic patients. Therefore ginger can be considered as an effective treatment for prevention of diabetes complications.

A refined-JinQi-JiangTang tablet ameliorates prediabetes by reducing insulin resistance and improving beta cell function in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Refined-JQ (JQ-R) is a mixture of refined extracts from three major herbal components of JinQi-JiangTang tablet: Coptis chinensis (Ranunculaceae), Astragalus membranaceus (Leguminosae), and Lonicera japonica (Caprifoliaceae). Our previous studies have indicated that JQ-R could decrease fasting blood glucose levels in diabetic mice and insulin resistance mice. Investigating the hypoglycemic effect of JQ-R on prediabetes has practical application value for preventing or delaying insulin resistance, impaired glucose tolerance and possibly the development of clinical diabetes.

MATERIALS AND METHODS

The anti-diabetic potential of JQ-R was investigated using a high fat-diet (HFD)-induced obesity mouse model. C57BL/6J mice (HFD-C57 mice) were fed with high-fat diet for 4 months. HFD-C57 mice were treated with either JQ-R (administered intragastrically once daily for 4 weeks) or metformin (as positive control), and the effects of JQ-R on body weight, blood lipids, glucose metabolism, insulin sensitivity, and beta cell function were monitored.

RESULTS

The body weight, serum cholesterol, and the Homeostasis Model Assessment ratio (insulin resistance index) were significantly reduced in JQ-R or metformin-treated mice, and the glucose tolerance was enhanced and insulin response was improved simultaneously. Moreover, both JQ-R and metformin could activate liver glycogen syntheses even under a relatively high glucose loading. Although glyconeogenesis was inhibited in the metformin treated mice, it was not observed in JQ-R treated mice. Similar to metformin, JQ-R could also improve the glucose infusion rate (GIR) in hyperglycemic clamp test. JQ-R was also shown to increase the levels of phosphorylated AMPKα and phosphorylated acetyl CoA carboxylase (ACC), similar to metformin.

CONCLUSION

JQ-R could reduce HFD-induced insulin resistance by regulating glucose and lipid metabolism, increasing insulin sensitivity through activating the AMPK signaling pathway, and subsequently improving β cell function. Therefore, JQ-R may offer an alternative in treating disorders associated with insulin resistance, such as prediabetes and T2DM.

White vegetables: glycemia and satiety

The objective of this review is to discuss the effect of white vegetable consumption on glycemia, satiety, and food intake. White vegetables is a term used to refer to vegetables that are white or near white in color and include potatoes, cauliflowers, turnips, onions, parsnips, white corn, kohlrabi, and mushrooms (technically fungi but generally considered a vegetable). They vary greatly in their contribution to the energy and nutrient content of the diet and glycemia and satiety. As with other foods, the glycemic effect of many white vegetables has been measured. The results illustrate that interpretation of the semiquantitative comparative ratings of white vegetables as derived by the glycemic index must be context dependent. As illustrated by using the potato as an example, the glycemic index of white vegetables can be misleading if not interpreted in the context of the overall contribution that the white vegetable makes to the carbohydrate and nutrient composition of the diet and their functionality in satiety and metabolic control within usual meals. It is concluded that application of the glycemic index in isolation to judge the role of white vegetables in the diet and, specifically in the case of potato as consumed in ad libitum meals, has led to premature and possibly counterproductive dietary guidance.

(S)-[6]-Gingerol inhibits TGF-β-stimulated biglycan synthesis but not glycosaminoglycan hyperelongation in human vascular smooth muscle cells

Objectives

(S)-[6]-Gingerol is under investigation for a variety of therapeutic uses. Transforming growth factor (TGF)-β stimulates proteoglycan synthesis, leading to increased binding of low-density lipoproteins, which is the initiating step in atherosclerosis. We evaluated the effects of (S)-[6]-gingerol on these TGF-β-mediated proteoglycan changes to explore its potential as an anti-atherosclerotic agent.

Methods

Purified (S)-[6]-gingerol was assessed for its effects on proteoglycan synthesis by [35S]-sulfate incorporation into glycosaminoglycan chains and [35S]-Met/Cys incorporation into proteoglycans and total proteins in human vascular smooth muscle cells. Biglycan level was assessed by real-time quantitative polymerase chain reactions and the effects of (S)-[6]-gingerol on TGF-β signalling by assessment of the phosphorylation of Smads and Akt by western blotting.

Key findings

(S)-[6]-Gingerol concentration-dependently inhibited TGF-β-stimulated proteoglycan core protein synthesis, and this was not secondary to inhibition of total protein synthesis. (S)-[6]-Gingerol inhibited biglycan mRNA expression. (S)-[6]-Gingerol did not inhibit TGF-β-stimulated glycosaminoglycan hyperelongation or phosphorylation of Smad 2, in either the carboxy terminal or linker region, or Akt phosphorylation.

Conclusions

The activity of (S)-[6]-gingerol to inhibit TGF-β-stimulated biglycan synthesis suggests a potential role for ginger in the prevention of atherosclerosis or other lipid-binding diseases. The signalling studies indicate a novel site of action of (S)-[6]-gingerol in inhibiting TGF-β responses.

Preventive and Protective Properties of Zingiber officinale (Ginger) in Diabetes Mellitus, Diabetic Complications, and Associated Lipid and Other Metabolic Disorders: A Brief Review

Zingiber officinale (ginger) has been used as herbal medicine to treat various ailments worldwide since antiquity. Recent evidence revealed the potential of ginger for treatment of diabetes mellitus. Data from in vitro, in vivo, and clinical trials has demonstrated the antihyperglycaemic effect of ginger. The mechanisms underlying these actions are associated with insulin release and action, and improved carbohydrate and lipid metabolism. The most active ingredients in ginger are the pungent principles, gingerols, and shogaol. Ginger has shown prominent protective effects on diabetic liver, kidney, eye, and neural system complications. The pharmacokinetics, bioavailability, and the safety issues of ginger are also discussed in this update.

Treatment with ginger ameliorates fructose-induced Fatty liver and hypertriglyceridemia in rats: modulation of the hepatic carbohydrate response element-binding protein-mediated pathway

Ginger has been demonstrated to improve lipid derangements. However, its underlying triglyceride-lowering mechanisms remain unclear. Fructose overconsumption is associated with increase in hepatic de novo lipogenesis, thereby resulting in lipid derangements. Here we found that coadministration of the alcoholic extract of ginger (50 mg/kg/day, oral gavage, once daily) over 5 weeks reversed liquid fructose-induced increase in plasma triglyceride and glucose concentrations and hepatic triglyceride content in rats. Plasma nonesterified fatty acid concentration was also decreased. Attenuation of the increased vacuolization and Oil Red O staining area was evident on histological examination of liver in ginger-treated rats. However, ginger treatment did not affect chow intake and body weight. Further, ginger treatment suppressed fructose-stimulated overexpression of carbohydrate response element-binding protein (ChREBP) at the mRNA and protein levels in the liver. Consequently, hepatic expression of the ChREBP-targeted lipogenic genes responsible for fatty acid biosynthesis was also downregulated. In contrast, expression of neither peroxisome proliferator-activated receptor- (PPAR-) alpha and its downstream genes, nor PPAR-gamma and sterol regulatory element-binding protein 1c was altered. Thus the present findings suggest that in rats, amelioration of fructose-induced fatty liver and hypertriglyceridemia by ginger treatment involves modulation of the hepatic ChREBP-mediated pathway.

Ginger consumption enhances the thermic effect of food and promotes feelings of satiety without affecting metabolic and hormonal parameters in overweight men: a pilot study

Evidence suggests that ginger consumption has anti-inflammatory, anti-hypertensive, glucose-sensitizing, and stimulatory effects on the gastrointestinal tract. This study assessed the effects of a hot ginger beverage on energy expenditure, feelings of appetite and satiety and metabolic risk factors in overweight men. Ten men, age 39.1±3.3 y and body mass index (BMI) 27.2±0.3 kg/m(2), participated in this randomized crossover study. Resting state energy expenditure was measured using indirect calorimetry and for 6h after consumption of a breakfast meal with or without 2 g ginger powder dissolved in a hot water beverage. Subjective feelings of satiety were assessed hourly using visual analog scales (VAS) and blood samples were taken fasted and for 3 h after breakfast consumption. There was no significant effect of ginger on total resting energy expenditure (P=.43) or respiratory quotient (P=.41). There was a significant effect of ginger on thermic effect of food (ginger vs control=42.7±21.4 kcal/d, P=.049) but the area under the curve was not different (P=.43). VAS ratings showed lower hunger (P=.002), lower prospective food intake (P=.004) and greater fullness (P=.064) with ginger consumption versus control. There were no effects of ginger on glucose, insulin, lipids, or inflammatory markers. The results, showing enhanced thermogenesis and reduced feelings of hunger with ginger consumption, suggest a potential role of ginger in weight management. Additional studies are necessary to confirm these findings.

Attenuation of liver pro-inflammatory responses by Zingiber officinale via inhibition of NF-kappa B activation in high-fat diet-fed rats

The aim of this study was to investigate whether treatment with a ginger (Zingiber officinale) extract of high-fat diet (HFD)-fed rats suppresses Nuclear factor-kappa B (NF-κB)-driven hepatic inflammation and to subsequently explore the molecular mechanisms in vitro. Adult male Sprague-Dawley rats were treated with an ethanolic extract of Zingiber officinale (400 mg/kg) along with a HFD for 6 weeks. Hepatic cytokine mRNA levels, cytokine protein levels and NF-κB activation were measured by real-time PCR, Western blot and an NF-κB nuclear translocation assay, respectively. In vitro, cell culture studies were carried out in human hepatocyte (HuH-7) cells by treatment with Zingiber officinale (100 μg/mL) for 24 hr prior to interleukin-1β (IL-1β, 8 ng/mL)-induced inflammation. We showed that Zingiber officinale treatment decreased cytokine gene TNFα and IL-6 expression in HFD-fed rats, which was associated with suppression of NF-κB activation. In vitro, Zingiber officinale treatment decreased NF-κB-target inflammatory gene expression of IL-6, IL-8 and serum amyloid A1 (SAA1), while it suppressed NF-κB activity, IκBα degradation and IκB kinase (IKK) activity. In conclusion, Zingiber officinale suppressed markers of hepatic inflammation in HFD-fed rats, as demonstrated by decreased hepatic cytokine gene expression and decreased NF-κB activation. The study demonstrates that the anti-inflammatory effect of Zingiber officinale occurs at least in part through the NF-κB signalling pathway.

Platycodon grandiflorum modifies adipokines and the glucose uptake in high-fat diet in mice and L6 muscle cells

OBJECTIVES

Obesity and diabetes have become the most common human health problems worldwide. Obesity's contribution to type 2 diabetes might be due to dysregulation of adipokines and glucose uptake.

METHODS

In this study, we performed in-vivo and in-vitro studies to evaluate the effects of Platycodon grandiflorum extract (PGE) on adipokines and glucose uptake. Before study, platycodin D concentrations were analysed by HPLC in PGE prepared in water, in 50% ethanol and in 80% ethanol, and we selected the 80% ethanol extract as the PGE for this study based on the HPLC results.

KEY FINDINGS

We found that inclusion of PGE in the high-fat diet (HFD) markedly attenuated food intake, body weight, epididymal fat weight, adipocyte size and blood glucose levels by the oral glucose tolerance test in mice, and maintained serum levels of adiponectin, resistin, leptin, fructosamine and triglycerides. Gene expression analysis revealed that PGE up-regulated adiponectin, and down-regulated TNF-α and leptin in fat tissue. In L6 muscle cells in vitro, PGE increased insulin-stimulated glucose uptake.

CONCLUSIONS

  We conclude that PGE may improve obesity in mice fed an HFD and glucose uptake in L6 muscle cells by modifying adipokines, and could offer clinical benefits as a supplement to treat obesity and diabetes.

An impression on current developments in the technology, chemistry, and biological activities of ginger (Zingiber officinale Roscoe)

Ginger rhizome (Zingiber officinale Roscoe) is widely cultivated as a spice for its aromatic and pungent components. The essential oil and oleoresins from ginger are valuable products responsible for the characteristic flavor and pungency. Both are used in several food products such as soft beverages and also in many types of pharmaceutical formulations. More than 100 compounds have been reported from ginger, some of which are isolated and characterized, others are tentatively identified by GC-MS and / or LC-MS. [6]-Gingerol, the major gingerol in ginger rhizomes, has been found to possess many interesting pharmacological and physiological activities, such as anti-inflammatory, analgesic, and cardiotonic effects. Ginger is considered as "generally recognized as safe" (GRAS) by Food and Drug Administration (FDA), USA. Due to all these properties, ginger has gained considerable attention in developed countries in recent years, especially for its use in the treatment of inflammatory conditions. The present review is a persuasive presentation of the current information on processing, chemistry, biological activities, and medicinal uses of ginger. Further studies are required for the validation of the beneficial uses. Formulation for novel products and new usages may emerge in the years to come, based on the revealed results of various studies.

Bifidobacterium adolescentis supplementation ameliorates visceral fat accumulation and insulin sensitivity in an experimental model of the metabolic syndrome

The aim of the present study was to investigate the effects of Bifidobacterium adolescentis (Bif) supplementation on visceral fat accumulation and insulin sensitivity of the metabolic syndrome in HF-diet-fed rats. Adult male Wistar rats (n 10 per group) were fed four different experimental diets for 12 weeks as follows: standard diet; high-fat (HF) diet; a mix of HF diet and Bif; a mix of standard diet and Bif. Liver, mesenteric fat, epididymal fat, retroperitoneal fat, and inguinal fat, pancreas and triceps surae in all four groups of the rats were weighed, while liver steatosis and insulin sensitivity were evaluated at the end point of the study. As the number of intestinal Bifidobacterium species decreased obviously, fat pad weight and body weight increased significantly in the HF group compared with in the other three groups (P <0·05). Addition of Bif led to a reduction in body weight and fat pad weight (P <0·05). With an increase in liver weight, more severe steatosis of hepatocytes was observed in the HF group compared with in the other three groups. A significant decrease of the glucose infusion rate and pancreas weight was found in the HF group (P <0·05). This deleterious effect was alleviated when Bif was added to the diets. Bifidobacterium supplementation ameliorated visceral fat accumulation and insulin sensitivity of the metabolic syndrome in HF-diet-fed rats.

Synthesis of a new [6]-gingerol analogue and its protective effect with respect to the development of metabolic syndrome in mice fed a high-fat diet

To determine the effects of a [6]-gingerol analogue (6G), a major chemical component of the ginger rhizome, and its stable analogue after digestion in simulated gastric fluid, aza-[6]-gingerol (A6G), on diet-induced body fat accumulation, we synthesized 6G and A6G. Mice were fed either a control regular rodent chow, a high-fat diet (HFD), or a HFD supplemented with 6G and A6G. Magnetic resonance imaging adiposity parameters of the 6G- and A6G-treated mice were compared with those of control mice. Supplementation with 6G and A6G significantly reduced body weight gain, fat accumulation, and circulating levels of insulin and leptin. The mRNA levels of sterol regulatory element-binding protein 1c (SREBP-1c) and acetyl-CoA carboxylase 1 in the liver were significantly lower in mice fed A6G than in HFD control mice. Our findings indicate that A6G, rather than 6G, enhances energy metabolism and reduces the extent of lipogenesis by downregulating SREBP-1c and its related molecules, which leads to the suppression of body fat accumulation.

Ginger and its health claims: molecular aspects

Recent research has rejuvenated centuries-old traditional herbs to cure various ailments by using modern tools like diet-based therapy and other regimens. Ginger is one of the classic examples of an herb used for not only culinary preparations but also for unique therapeutic significance owing to its antioxidant, antimicrobial, and anti-inflammatory potential. The pungent fractions of ginger, namely gingerols, shogaols, paradols, and volatile constituents like sesquiterpenes and monoterpenes, are mainly attributed to the health-enhancing perspectives of ginger. This review elucidates the health claims of ginger and the molecular aspects and targets, with special reference to anticancer perspectives, immunonutrition, antioxidant potential, and cardiovascular cure. The molecular targets involved in chemoprevention like the inhibition of NF-κB activation via impairing nuclear translocation, suppresses cIAP1 expression, increases caspase-3/7 activation, arrests cell cycle in G2 + M phases, up-regulates Cytochrome-c, Apaf-1, activates PI3K/Akt/I kappaB kinases IKK, suppresses cell proliferation, and inducts apoptosis and chromatin condensation. Similarly, facts are presented regarding the anti-inflammatory response of ginger components and molecular targets including inhibition of prostaglandin and leukotriene biosynthesis and suppression of 5-lipoxygenase. Furthermore, inhibition of phosphorylation of three mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2), and c-Jun N-terminal kinase (JNK) are also discussed. The role of ginger in reducing the extent of cardiovascular disorders, diabetes mellitus, and digestive problems has also been described in detail. Although, current review articles summarized the literature pertaining to ginger and its components. However, authors are still of the view that further research should be immediately carried out for meticulousness.

Safety and efficacy of Zingiber officinale roots on fertility of male diabetic rats

The acute toxicity of methanolic and watery extracts of Zingiber officinale (ZO) roots in mice and their effects on fertility of male diabetic rats were carried out. The fertility experiment was done on six groups of male rats one of them was kept as normal control, while the others were rendered diabetic by subcutaneous injection of alloxan (120 mg kg(-1)). One group was left as diabetic control, while the others were given orally either methanolic (100 and 200 mg kg(-1)) or watery extract (150 and 300 mg kg(-1)) for 65 consecutive days. The results showed that no mortalities occur when both extracts were given orally to mice in doses up to 5 g kg(-1) b.wt. Both extracts increased fertility index, sexual organs weight, serum testosterone level and sperm motility and count. Histopathological examination of the testes of diabetic rats showed mild to moderate degenerative changes of spermatogenic cells, diffuse edema and incomplete arrest of spermatogenesis. Treatment with ZO extracts caused alleviation of the testicular lesions that appeared in non-treated diabetic rats. Conclusively, extracts of ZO have high safety in mice and intake of ZO roots as a drink may be useful for diabetic patients who suffer from sexual impotency.

Regulation of low-density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme A reductase expression by Zingiber officinale in the liver of high-fat diet-fed rats

Zingiber officinale has been used to control lipid disorders and reported to possess remarkable cholesterol-lowering activity in experimental hyperlipidaemia. In the present study, the effect of a characterized and standardized extract of Zingiber officinale on the hepatic lipid levels as well as on the hepatic mRNA and protein expression of low-density lipoprotein (LDL) receptor and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was investigated in a high-fat diet-fed rat model. Rats were treated with an ethanol extract of Zingiber officinale (400 mg/kg) extract along with a high-fat diet for 6 weeks. The extract of Zingiber officinale significantly decreased hepatic triglyceride and tended to decrease hepatic cholesterol levels when administered over 6 weeks to the rats fed a high-fat diet. We found that in parallel, the extract up-regulated both LDL receptor mRNA and protein level and down-regulated HMG-CoA reductase protein expression in the liver of these rats. The metabolic control of body lipid homeostasis is in part due to enhanced cholesterol biosynthesis and reduced expression of LDL receptor sites following long-term consumption of high-fat diets. The present results show restoration of transcriptional and post-transcriptional changes in low-density lipoprotein and HMG CoA reductase by Zingiber officinale administration with a high-fat diet and provide a rational explanation for the effect of ginger in the treatment of hyperlipidaemia.

Enzyme changes and glucose utilisation in diabetic rabbits: the effect of Gymnema sylvestre, R.Br

The administration of the dried leaf powder of Gymnema sylvestre regulates the blood sugar levels in alloxan diabetic rabbits. G. sylvestre therapy not only produced blood glucose homeostasis but also increased the activities of the enzymes affording the utilisation of glucose by insulin dependent pathways: it controlled phosphorylase levels, gluconeogenic enzymes and sorbitol dehydrogenase. The uptake and incorporation of [14C] glucose into the glycogen and protein are increased in the liver, kidney and muscle in G. sylvestre administered diabetic animals when compared to the untreated diabetic animals. Pathological changes initiated in the liver during the hyperglycemic phase are reversed by controlling hyperglycemia by G. sylvestre. G. sylvestre, a herb used for the control of diabetes mellitus in several parts of India, appears to correct the metabolic derangements in diabetic rabbit liver, kidney and muscle.