Metabolic response of soy pinitol on lipid-lowering, antioxidant and hepatoprotective action in hamsters fed-high fat and high cholesterol diet

d-Pinitol promotes tau dephosphorylation through a cyclin-dependent kinase 5 regulation mechanism: A new potential approach for tauopathies?

Background and Purpose

Recent evidence links brain insulin resistance with neurodegenerative diseases, where hyperphosphorylated tau protein contributes to neuronal cell death. In the present study, we aimed to evaluate if d‐pinitol inositol, which acts as an insulin sensitizer, affects the phosphorylation status of tau protein.

Experimental Approach

We studied the pharmacological effect of d‐pinitol on insulin signalling and tau phosphorylation in the hippocampus of Wistar and Zucker rats. To this end, we evaluated by western blotting the Akt pathway and its downstream proteins as being one of the main insulin‐mediator pathways. Also, we explored the functional status of additional kinases phosphorylating tau, including PKA, ERK1/2, AMPK and CDK5. We utilized the 3xTg mouse model as a control for tauopathy, since it carries tau mutations that promote phosphorylation and aggregation.

Key Results

Surprisingly, we discovered that oral d‐pinitol treatment lowered tau phosphorylation significantly, but not through the expected kinase GSK‐3 regulation. An extensive search for additional kinases phosphorylating tau revealed that this effect was mediated through a mechanism dependent on the reduction of the activity of the CDK5, affecting both its p35 and p25 subunits. This effect disappeared in leptin‐deficient Zucker rats, uncovering that the association of leptin deficiency, obesity, dyslipidaemia and hyperinsulinaemia abrogates d‐pinitol actions on tau phosphorylation. The 3xTg mice confirmed d‐pinitol effectiveness in a genetic AD‐tauopathy.

Conclusion and Implications

The present findings suggest that d‐pinitol, by regulating CDK5 activity through a decrease of CDK5R1, is a potential drug for developing treatments for neurological disorders such as tauopathies.

Study of the Potential Hepatoprotective Effect of Myo-Inositol and Its Influence on Zebrafish Development

Inositol is a natural substance found widely in plants. It is used in therapies for many medical cases. The aim of this study was to determine the toxicity of myo-inositol (MI) and to investigate its potential hepatoprotective character. In the first part of the study, zebrafish embryos were incubated with 5, 10, 20, 40, 60, 80, and 100 mg/mL MI. Endpoints such as survivability, hatching rate, malformation, and mobility were evaluated. Our results demonstrated that the high doses of MI lead to increased mortality and malformations and reduce the hatching rate in comparison to the control group. Moreover, low doses of this compound do not produce a negative effect on zebrafish and even have the ability to increase the hatching rate and mobility. In the second part of the study, the hepatoprotective effect of MI was tested. Zebrafish larvae from the line Tg (fabp10a:DsRed) were incubated for 24 h with 1% and 2% ethanol (EtOH), 5 mg/mL of MI with 1% EtOH, and 5 mg/mL of MI with 2% EtOH. No significant differences between the groups with EtOH and the group treated with EtOH with MI were observed. Our results suggest that MI has no positive benefits on hepatocytes of zebrafish larvae.

d-Pinitol protects against endoplasmic reticulum stress and apoptosis in hepatic ischemia-reperfusion injury via modulation of AFT4-CHOP/GRP78 and caspase-3 signaling pathways

Hepatic ischemia-reperfusion injury (IRI) is a major unavoidable clinical problem often accompanying various liver surgery and transplantation. d-Pinitol, a cyclic polyol, exhibits hepatoprotective efficacy. The objective of this study is to determine the possible mechanism of action of pinitol against endoplasmic reticulum (ER) stress regulation-mediated hepatic IRI and compare its effects with thymoquinone (TQ) in experimental rats. Male Sprague Dawley rats were pre-treated orally with either vehicle (DMSO) or d-Pinitol (5, 10, and 20 mg/kg) or TQ (30 mg/kg) for 21 days and subjected to 60 min of partial hepatic ischemia followed by 24 h of reperfusion. Pre-treatment with pinitol (10 and 20 mg/kg) effectively (P < 0.05) protected against IRI-induced hepatic damage reflected by attenuation of elevated oxidative stress and pro-inflammatory cytokines. Additionally, western blot and ELISA analyses suggested that pinitol significantly (P < 0.05) down-regulated expression of endoplasmic reticulum stress apoptotic markers, namely glucose-regulated protein (GRP)-78, CCAAT/enhancer-binding protein homologous protein (CHOP), activating transcription factor (AFT)-4 and -6α, X-box binding protein-1, and caspase-3, 9, and 12. Additionally, pinitol pre-treatment effectively (P < 0.05) improved mitochondrial function and phosphorylation of Extracellular signal-regulated kinase (ERK)-1/2 and p38. Pinitol markedly (P < 0.05) protected hepatic apoptosis determined by flow cytometry. Further, pinitol provided effective (P < 0.05) protection against hepatic histological and ultrastructural aberrations induced by IRI. TQ showed more pronounced protective effect against attenuation of IRI-induced hepatic injury as compared to d-Pinitol. Pinitol offered protection against endoplasmic reticulum stress-mediated phosphorylation of ERK1/2 and p38, thereby inhibiting AFT4-CHOP/GRP78 signaling response and caspase-3 induced hepatocellular apoptosis during hepatic ischemia-reperfusion insults. Thus, Pinitol can be considered as a viable option for the management of hepatic IRI.

Compounds of plants with activity against SARS-CoV-2 targets

INTRODUCTION

The COVID-19 global pandemic is a public health emergency due to its high virulence and mortality. Many vaccine development studies at clinical trials are currently conducted to combat SARS-CoV-2. Plants are a rich source of phytochemicals with different biological activities, including antiviral activities, which are the focus of many studies.

AREAS COVERED

This review shows compounds of traditional plants listed on RENISUS list have therapeutic properties against SARS-CoV-2 targets.

EXPERT OPINION

The rise of new variants, more pathogenic and virulent, impacts in the increase of mortality from SARS-CoV-2 infection, and thus, the control of the outbreaks of disease remains a global challenge. Other's drug and vaccines development is an essential element in controlling SARS-COV-2. Therefore, it is imperative that approach to tackle this pandemic has to be solidly evidence-informed. It should be noticed that the immune system does play critical roles in fighting viruses. Studies show that T cells levels decreased continuously as the disease progressed. T cell-mediated cellular immune response, probably by immunological memory, is essential for direct virus eradication after infection whilst B cells functions in producing antibodies that neutralize virus.But, have distinct patterns of T cell response exist in different patients, suggesting the possibility of distinct clinical approaches. Efforts are concentrated to elucidate the underlying immunological mechanisms in SARS-CoV-2 pathogenesis and progression for better design of diagnostic, therapeutic and preventive strategies. We seek to identify biomolecules with the potential to act in biomarkers that predict how severe the disease can get. But it is important to warn that the plants that produce the compounds mentioned here should not be used without a physician prescription. Finally, we speculate that these compounds may eventually attract the attention of physicians and researchers to perform tests in specific contexts of SARS-CoV-2 infection, and if they show positive results, be tested in Clinical trials.

D-Pinitol Increases Insulin Secretion and Regulates Hepatic Lipid Metabolism in Msg-Obese Mice

D-pinitol is one of the major inositol found in plants and studies suggest its potential hypoglycemic and hypolipidemic actions in diabetic rodents. Here, we investigated the actions of D-pinitol on adiposity, and in lipid and glycemic homeostasis in monosodium glutamate (MSG)-obese mice. Swiss mice received daily subcutaneous injections of MSG [(4g/kg of body weight (BW)] or saline [1.25g/kg BW; control (CTL)] during their first five days of life. From 90-120 day-old, half of the MSG and CTL groups received 50 mg D-pinitol/kg BW/day (MPIN and CPIN groups) or vehicle (saline; MSG and CTL groups) by gavage. MSG mice displayed higher abdominal adiposity and hepatic triglycerides (TG) deposition, and increased hepatic expression of lipogenic genes (SREBP-1c, ACC-1 and FASN), but downregulation in AMPKα mRNA. MSG mice also exhibited hyperinsulinemia, islet hypersecretion and hypertrophy, glucose intolerance and insulin resistance. D-pinitol did not change adiposity, glucose intolerance, insulin resistance, but increased hepatic triglycerides (TG) content in MPIN mice, which was associated with increases in gene expressions of SREBP-1c and FASN, but reduction in AMPKα. Furthermore, D-pinitol enhanced insulin secretion in MPIN and CPIN groups. Therefore, D-pinitol enhanced glucose-induced insulin secretion, which may account to enhances hepatic lipogenesis and TG deposition in MPIN mice.

Inositol and Non-Alcoholic Fatty Liver Disease: A Systematic Review on Deficiencies and Supplementation

Liver lipid accumulation is a hallmark of non-alcoholic fatty liver disease (NAFLD), broadly associated with insulin resistance. Inositols (INS) are ubiquitous polyols implied in many physiological functions. They are produced endogenously, are present in many foods and in dietary supplements. Alterations in INS metabolism seems to play a role in diseases involving insulin resistance such as diabetes and polycystic ovary syndrome. Given its role in other metabolic syndromes, the hypothesis of an INS role as a supplement in NAFLD is intriguing. We performed a systematic review of the literature to find preclinical and clinical evidence of INS supplementation efficacy in NAFLD patients. We retrieved 10 studies on animal models assessing Myoinosiol or Pinitol deficiency or supplementation and one human randomized controlled trial (RCT). Overall, INS deficiency was associated with increased fatty liver in animals. Conversely, INS supplementation in animal models of fatty liver reduced hepatic triglycerides and cholesterol accumulation and maintained a normal ultrastructural liver histopathology. In the one included RCT, Pinitol supplementation obtained similar results. Pinitol significantly reduced liver fat, post-prandial triglycerides, AST levels, lipid peroxidation increasing glutathione peroxidase activity. These results, despite being limited, indicate the need for further evaluation of INS in NAFLD in larger clinical trials.

Soy intake and chronic disease risk: findings from prospective cohort studies in Japan

There has been much interest in the potential role of soy in reducing the risk of chronic diseases. Soy foods are uniquely rich in isoflavones, a fact that has triggered much research including intervention studies. However, there have been few long-term prospective observational studies that include disease itself as an outcome. High intake of soy foods is intrinsic to the Japanese diet, which can be advantageous for conducting such studies in Japan. The present report reviews the findings from Japanese prospective cohort studies on soy intake and the risk of cardiovascular diseases, cancer, type 2 diabetes, osteoporosis, menopausal symptoms, and dementia. The results suggest a beneficial role of soy in several chronic diseases, but they are not without controversy. Discrepancies have been observed in the findings of studies of Japanese or other Asians as compared to those of non Asians. This review discusses the issues to be explored in future studies.

Soy and Isoflavone Consumption and Multiple Health Outcomes: Umbrella Review of Systematic Reviews and Meta-Analyses of Observational Studies and Randomized Trials in Humans

SCOPE

To assess the existing evidence of associations between consumption of soy and isoflavone and multiple health outcomes.

METHODS AND RESULTS

This is an umbrella review of meta-analyses and systematic reviews of randomized trials and observational studies in humans. 114 Meta-analyses and systematic reviews are identified with 43 unique outcomes. Soy and isoflavone consumption seems more beneficial than harmful for a series of health outcomes. Beneficial associations are identified for cancers, cardiovascular disease, gynecological, metabolic, musculoskeletal, endocrine, neurological, and renal outcomes, particularly in perimenopausal women. Harmful association is only found for gastric cancer (RR: 1.17, 95% CI: 1.02-1.36) for high intake of miso soup (1-5 cups per day) in male.

CONCLUSION

Generally, soy and isoflavone consumption is more beneficial than harmful. The results herein support promoting soy intake as part of a healthy diet. Randomized controlled trials are necessary to confirm this finding.

Nuciferine Prevents Hepatic Steatosis by Regulating Lipid Metabolismin Diabetic Rat Model

Objective

This study investigatesthe nuciferine capacity to regulate the liver’s lipid metabolism regarding steatosis and injury in STZ-induced diabetic rats.

Materials and Methods

The rats were randomly divided into groups control, diabetic and nuciferine 200 mg/kg/ day treatment. After 4 days of STZ injection, the nuciferine group was treated and administered via oral gavages for 4 weeks. At the end of experiment, blood, liver, myocardial and muscular samples were collected.

Results

Nuciferine-treated significantly increased the body weight from 339.4g to 367.8g, but significantly decreased the food and water intake compared with diabetic rats. Also, the nuciferine-treated rats had significantly decreased TC, TG, and FFAs in the liver compared with the diabetic group, especially the serum markers of blood glucose. These were associated with the gene expression related to lipogenesis which was significantly down-regulated; the gene expression involved in lipolysis and fatty acid β-oxidation was significantly up-regulated. Discussion and

Conclusion

The data provide evidence that nuciferine supplementation could protect the liver by regulating lipid metabolism gene expression resulting in decreasing the steatosis and injury in diabetic rat. Thus, nuciferine could be developed as a diabetic adjuvant food additive in future.

The Healing-Promoting Properties of Selected Cyclitols-A Review

INTRODUCTION

Myo-inositol and its derivatives cyclitols play an important role in the processes of cell regulation, signal transduction, osmoregulation, and ion channel physiology, and are a component of the cell membrane. Free cyclitols present in food or released during the degradation of galactosyl cyclitols by bacteria (in digestive tract) show some physiological benefits.

AIM

The aim of this paper is to present and analyze the documented data about curative and healing properties of cyclitols.

RESULTS AND DISCUSSION

Cyclitols are well known compounds in the treatment of an accompanied diabetes insulin resistance, and also obesity and polycystic ovarian syndrome. d-chiro-Inositol deficiency exacerbates insulin resistance in the liver, muscles, and fat, while depletion of myo-inositol results in the development of diabetic complications. Cyclitols are successfully applied in treatment of polycystic ovarian syndrome, simultaneous are observed effective reducing of BMI, improving the hormonal profile, and increasing fertility. Moreover, cyclitols have anti-atherogenic, anti-oxidative, anti-inflammatory, and anti-cancer properties.

CONCLUSION

The properties of cyclitols may be a good therapeutic option in the reduction of metabolically induced inflammation. Due to well drugs tolerance and low toxicity of these compounds, cyclitols are recommend for pregnant women and also for children. Another advantage is their widespread presence and easy availability, which encourages their use in medicine.

Comparison of myo-inositol and metformin on mental health parameters and biomarkers of oxidative stress in women with polycystic ovary syndrome: a randomized, double-blind, placebo-controlled trial

INTRODUCTION

Data on comparison of myo-inositol and metformin on mental health parameters and biomarkers of oxidative stress in subjects with polycystic ovary syndrome (PCOS) are scarce. This purpose of this study was to compare of myo-inositol and metformin on mental health parameters and biomarkers of oxidative stress in subjects with PCOS.

METHODS

This randomized controlled trial was conducted among 60 subjects diagnosed with PCOS according to the Rotterdam criteria. Subjects were randomly assigned into two groups to intake either myo-inositol (n = 30) or metformin (n = 30) for 12 weeks. Parameters of mental health were recorded at baseline and after the 12-week intervention. Fasting blood samples were obtained at baseline and the end of the study to determine biomarkers of biomarkers of oxidative stress.

RESULTS

After the 12-week intervention, changes in beck depression inventory total score (-1.0 ± 1.7 vs. -0.3 ± 0.7, p = 0.03), general health questionnaire scores (-1.7 ± 2.9 vs. -0.5 ± 1.2, p = 0.02), depression anxiety and stress scale scores (-3.9 ± 6.4 vs. -0.9 ± 1.9, p = 0.01) and plasma total antioxidant capacity (TAC) concentrations (+106.1 ± 69.6 vs. +2.1 ± 132.4 mmol/L, p < 0.001) in the myo-inositol group were significantly different from the changes in these indicators in the metformin group. Myo-inositol supplementation for 12 weeks among patients with PCOS did not affect plasma glutathione and malondialdehyde levels.

CONCLUSIONS

Overall, our data supported that myo-inositol supplementation for 12 weeks among patients with PCOS had favorable effects on parameters of mental health and plasma TAC levels.

Evaluation of Cycloferin Supplement on Health Parameters in Experimentally Induced Diabetic Rats with and Without Exogenous Insulin

Cycloferin is an extract of the chemicals from the Cyclopia species, which grows only in small areas in the southwest and southeast of South Africa and has been consumed traditionally as a nourishing tea to treat numerous health issues and illnesses. Previous studies report that some of the active compounds in Cycloferin, such as pinitol (a modified sugar) and mangiferin (a glucoside), may reduce blood sugar levels and therefore may be used as a treatment for diabetes. Mangiferin, in particular, has been shown to stimulate carbohydrate oxidation and alleviate some effects of insulin resistance and hyperglycemia. Other active components of Cycloferin include flavones, isoflavones, coumestans, luteolin, 4-hydroxycinnamic acid, polyphenols, and xanthones. These active compounds are antioxidants, which can enhance glucose breakdown, lower blood lipids, and reduce the number of highly reactive compounds known as free radicals, which can alter cellular structure and function when present in large amounts. In this study, we explored the ameliorative effects of Cycloferin by treating streptozotocin- (STZ) injected rats with Cycloferin and evaluating its long-term and short-term effect on blood glucose levels and kidney and liver conditions of the diabetic-rendered rats. Our results demonstrated the ability of Cycloferin to both lower the blood glucose levels and reduce evidence of damage in kidney and liver in diabetic rats with and without exogenous insulin treatment for partial control of diabetic state.

The effects of inositol supplementation on lipid profiles among patients with metabolic diseases: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Several studies have evaluated the effect of inositol supplementation on lipid profiles among population with metabolic diseases; however, the findings are controversial. This review of randomized controlled trials (RCTs) was performed to summarize the evidence of the effects of inositol supplementation on lipid profiles among population with metabolic diseases.

METHODS

Relevant RCTs studies were searched in Cochrane Library, EMBASE, MEDLINE, and Web of Science until October 2017. Two researchers assessed study eligibility, extracted data, and evaluated risk of bias of included primary studies, independently. To check for the heterogeneity among included studies Q-test and I₂ statistics were used. Data were pooled by using the random-effect model and standardized mean difference (SMD) was considered as summary of the effect size.

RESULTS

Overall, 14 RCTs were included into meta-analysis. Pooled results showed that inositol supplementation among patients with metabolic diseases significantly decreased triglycerides (SMD - 1.24; 95% CI, - 1.84, - 0.64; P < 0.001), total- (SMD - 1.09; 95% CI, - 1.83, - 0.55; P < 0.001), and LDL-cholesterol levels (SMD - 1.31; 95% CI, - 2.23, - 0.39; P = 0.005). There was no effect of inositol supplementation on HDL-cholesterol levels (SMD 0.20; 95% CI, - 0.27, 0.67; P = 0.40).

CONCLUSIONS

Inositol supplementation may result in reduction in triglycerides, total- and LDL-cholesterol levels, but did not affect HDL-cholesterol levels among patients with metabolic diseases. Additional prospective studies regarding the effect of inositol supplementation on lipid profiles in patients with metabolic diseases are necessary.

D‑Pinitol alleviates cyclosporine A‑induced renal tubulointerstitial fibrosis via activating Sirt1 and Nrf2 antioxidant pathways

Although the mechanism of cyclosporine A (CsA)-induced renal injury remains to be fully elucidated, accumulating evidence suggests that oxidative stress is critical in producing CsA-induced structural and functional renal impairment. The present study investigated the effect of D-pinitol, a cyclitol present in soybean, on chronic CsA nephropathy. Male ICR mice were treated with vehicle, CsA (30 mg/kg/day), D-pinitol (50 mg/kg/day) or a combination of CsA and D-pinitol for 28 days. To assess which pathway responding to oxidative stress is augmented by D-pinitol, the expression levels of several antioxidant enzymes and their possible regulators were measured. Treatment with D-pinitol significantly suppressed the increase of serum creatinine and decrease of urine osmolality, compared with the CsA control group. Histological examination of Masson's trichrome- and α-smooth muscle actin-stained renal tissue demonstrated that the CsA-induced tubulointerstitial fibrosis and inflammation were attenuated by D-pinitol. Following the administration of D-pinitol, there were increased expression levels of heme oxygenase-1, NAD(P)H:quinone oxidoreductase 1, superoxide dismutase 1 and catalase in CsA-treated kidneys. In addition, D-pinitol increased the level of sirtuin 1 (Sirt1), and the total and nuclear expression levels of nuclear erythroid factor 2-related factor 2 (Nrf2), suggesting that activation of the Sirt1 and Nrf2 pathways may induce the cellular antioxi dant system against CsA-induced nephropathy. Collectively, these data suggested that D-pinitol may protect the kidney from CsA-induced fibrosis, and that this renoprotective effect of D-pinitol was due to the inhibition of oxidative stress through the activation of Sirt1 and Nrf2, and the subsequent enhancement of antioxidant enzymes.

Improving the Concentrations of the Active Components in the Herbal Tea Ingredient, Uraria crinita: The Effect of Post-harvest Oven-drying Processing

Uraria crinita is widely used as a popular folk drink; however, little is known about how the post-harvest operations affect the chemical composition and bioactivity of UC. We assessed three drying methods (Oven-drying, Air-drying, Sun-drying), as well as the Oven-drying temperature using metabolomics approaches and bioactivity assays. The samples processed at 40 degree show a greater effect on the levels of estrogen receptor-alpha activity and nuclear factor erythroid 2-related factor 2 activity, anti-oxidative activity, and cyclooxygenase-2 inhibition compared with the other samples. A multivariate analysis showed a clear separation between the 40 degree Oven-dried samples and the other samples, which is consistent with the results of bioactivity assay. These results are ascribed to at least two-fold increase in the concentrations of flavonoids, spatholosineside A and triterpenoids in the oven-dried samples compared with the other groups. The proposed Oven-drying method at 40 degree results in an improved quality of UC.

Content of methylated inositols in familiar edible plants

Familiar plants contain large amounts of inositols; soybean, white clover, red clover, bush clover, locust tree, wisteria, and kudzu of the legume family contain pinitol (3-O-methyl-chiro-inositol) at approximately 200-600 mg/100 g fresh weight (FW). The contents of pinitol in other plants were 260 mg/100 g FW for sticky mouse-ear, 275 mg/100 g FW for chickweed, and 332 mg/100 g FW for ginkgo. chiro-Inositol of 191 and 156 mg/100 g FW was also found in dandelion and Japanese mallotus, respectively. Ononitol (4-O-methyl-myo-inositol) of 166 mg/100 g FW was found in sticky mouse-ear. Furthermore, young leaves of ginkgo contained sequoyitol (5-O-methyl-myo-inositol) of 287 mg/100 g FW. Hydroxyl radical scavenging activities of the methylated inositols were higher than those of the original inositols. Effective uses of these familiar edible plants are expected to promote good health.

Crude extracts from Lycium barbarum suppress SREBP-1c expression and prevent diet-induced fatty liver through AMPK activation

Lycium barbarum polysaccharide (LBP) is well known in traditional Chinese herbal medicine that, has beneficial effects. Previous study reported that LBP reduced blood glucose and serum lipids. However, the underlying LBP-regulating mechanisms remain largely unknown. The main purpose of this study was to investigate whether LBP prevented fatty liver through activation of adenosine monophosphate-activated protein kinase (AMPK) and suppression of sterol regulatory element-binding protein-1c (SREBP-1c). Male C57BL/6J mice were fed a low-fat diet, high-fat diet, or 100 mg/kg LBP-treatment diet for 24 weeks. HepG2 cells were treated with LBP in the presence of palmitic acid. In our study, LBP can improve body compositions and lipid metabolic profiles in high-fat diet-fed mice. Oil Red O staining in vivo and in vitro showed that LBP significantly reduced hepatic intracellular triacylglycerol accumulation. H&E staining also showed that LBP can attenuate liver steatosis. Hepatic genes expression profiles demonstrated that LBP can activate the phosphorylation of AMPK, suppress nuclear expression of SREBP-1c, and decrease protein and mRNA expression of lipogenic genes in vivo or in vitro. Moreover, LBP significantly elevated uncoupling protein-1 (UCP1) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) expression of brown adipose tissue. In summary, LBP possesses a potential novel treatment in preventing diet-induced fatty liver.

Scopoletin prevents alcohol-induced hepatic lipid accumulation by modulating the AMPK-SREBP pathway in diet-induced obese mice

OBJECTIVE

This study investigated the effects of scopoletin on alcohol-induced hepatic lipid accumulation in diet-induced obese mice and its mechanism.

MATERIAL/METHODS

Alcohol (25% v/v, 5g/kg body weight) was orally administered once a day for 6 weeks to mice fed with a high-fat diet (35%kcal) with or without scopoletin (0.05%, wt/wt).

RESULTS

Scopoletin reduced plasma acetaldehyde, fatty acid, total cholesterol, triglyceride and insulin levels, hepatic lipid and droplets and fasting blood glucose levels that were increased by alcohol. Scopoletin significantly activated hepatic AMPK and inhibited ACC and SREBP-1c and the activities of lipogenic enzymes, such as FAS, PAP and G6PD compared to the alcohol control group. Moreover, scopoletin significantly inhibited hepatic CYP2E1 activity and protein levels but elevated the activities of SOD, CAT, GSH-Px and GST and the levels of GSH compared to the alcohol control group. The hepatic lipid peroxide level was significantly lowered by scopoletin supplementation in alcohol-administered obese mice.

CONCLUSIONS

Taken together, these results suggested that scopoletin can ameliorate alcohol-induced hepatic lipid accumulation by modulating AMPK-SREBP pathway-mediated lipogenesis in mice fed a high-fat diet.

Ultrasound-assisted extraction of D-pinitol from carob pods using Response Surface Methodology

This study reports on the optimization of the conditions of extraction of D-pinitol compound from carob pods by using ultrasonication. For this purpose, the Box-Behnken design, which is a widely used form of Response Surface Methodology, was used to investigate the effects of parameters on the ultrasound-assisted extraction. Four independent variables, temperature (°C), ultrasonic power (W), dilution rate (material:water ratio) and time (min), were studied. The results showed that the highest D-pinitol concentration of 11.98 g/L was obtained with an extraction temperature of 50 °C, ultrasonic power of 207 W, a dilution rate of 1:4 and an extraction time of 120 min. It was found that the D-pinitol concentration of carob extract increased with the effect of ultrasonication during the extraction process. Therefore, ultrasound-assisted extraction could be used as an alternative to conventional hot water extraction with respect to the recovery of D-pinitol from carob pods with the advantages of lower extraction temperatures, shorter extraction time and reduced energy consumption.

Low doses of curcumin protect alcohol-induced liver damage by modulation of the alcohol metabolic pathway, CYP2E1 and AMPK

AIMS

This study investigated the hepatoprotective effects of low doses of curcumin against liver damage induced by chronic alcohol intake and a high-fat diet. We also examined several potential underlying mechanisms including action on alcohol metabolism, antioxidant activity, AMPK level and lipid metabolism.

MAIN METHOD

Alcohol (25% v/v, 5 g/kg body weight) was orally administered once a day for 6 weeks to mice fed a high-fat diet with or without two different doses of curcumin (0.02% and 0.05%, wt/wt).

KEY FINDINGS

Curcumin significantly decreased the plasma aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and alkaline phosphatase activities (p<0.05) and prevented hepatic steatosis compared with the alcohol control group. Curcumin significantly reversed the alcohol-induced inhibition of the alcohol dehydrogenase, aldehyde dehydrogenase 2 and antioxidant enzyme activities as well as the activation of cytochrome P4502E1 and promotion of lipid peroxidation (p<0.05). Curcumin significantly increased the hepatic total AMPK protein level and concomitantly suppressed the fatty acid synthase and phosphatidate phosphohydrolase activities compared with the alcohol control group (p<0.05). Furthermore, curcumin significantly lowered the plasma leptin, free fatty acids and triglycerides levels and hepatic lipid levels (p<0.05).

SIGNIFICANCE

These findings indicate that low doses of curcumin may protect against liver damage caused by chronic alcohol intake and a high-fat diet partly by modulating the alcohol metabolic enzyme activity, the antioxidant activity and the lipid metabolism. Therefore, curcumin may provide a promising natural therapeutic strategy against liver disease.

Nuciferine prevents hepatic steatosis and injury induced by a high-fat diet in hamsters

Background

Nuciferine is a major active aporphine alkaloid from the leaves of N. nucifera Gaertn that possesses anti-hyperlipidemia, anti-hypotensive, anti-arrhythmic, and insulin secretagogue activities. However, it is currently unknown whether nuciferine can benefit hepatic lipid metabolism.

Methodology/Principal Findings

In the current study, male golden hamsters were randomly divided into four groups fed a normal diet, a high-fat diet (HFD), or a HFD supplemented with nuciferine (10 and 15 mg/kg·BW/day). After 8 weeks of intervention, HFD-induced increases in liver and visceral adipose tissue weight, dyslipidemia, liver steatosis, and mild necroinflammation in hamsters were analyzed. Nuciferine supplementation protected against HFD-induced changes, alleviated necroinflammation, and reversed serum markers of metabolic syndrome in hamsters fed a HFD. RT-PCR and western blot analyses revealed that hamsters fed a HFD had up-regulated levels of genes related to lipogenesis, increased free fatty acid infiltration, and down-regulated genes involved in lipolysis and very low density lipoprotein secretion. In addition, gene expression of cytochrome P4502E1 and tumor necrosis factor-α were also increased in the HFD group. Nuciferine supplementation clearly suppressed HFD-induced alterations in the expression of genes involved in lipid metabolism.

Conclusions/Significance

Nuciferine supplementation ameliorated HFD-induced dyslipidemia as well as liver steatosis and injury. The beneficial effects of nuciferine were associated with altered expression of hepatic genes involved in lipid metabolism.

High hydrostatic pressure extract of garlic increases the HDL cholesterol level via up-regulation of apolipoprotein A-I gene expression in rats fed a high-fat diet

BACKGROUND

Cardiovascular disease (CVD) is the number one cause of mortality worldwide and a low high-density lipoprotein cholesterol (HDL-C) level is an important marker of CVD risk. Garlic (Allium sativum) has been widely used in the clinic for treatment of CVD and regulation of lipid metabolism. This study investigated the effects of a high hydrostatic pressure extract of garlic (HEG) on HDL-C level and regulation of hepatic apolipoprotein A-I (apoA-I) gene expression.

METHODS

Male Sprague-Dawley rats were divided into two groups and maintained on a high-fat control diet (CON) or high-fat control diet supplemented with high hydrostatic pressure extract of garlic (HEG) for 5 weeks. Changes in the expression of genes related to HDL-C metabolism were analyzed in liver, together with biometric and blood parameters.

RESULTS

In the HEG group, the plasma triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased in comparison with the CON group (P < 0.05). Dietary HEG also lowered the hepatic TG and total cholesterol (TC) levels compared to the CON group. While the plasma HDL-C level and mRNA level of hepatic apoA-I, which is one of primarily proteins of HDL-C particle, were significantly increased in the HEG group compared to the CON group (P < 0.05). The gene expression of ATP-binding cassette transporter A1 (ABCA1) and lecithin:cholesterol acyltransferase (LCAT), importantly involved in the biogenesis in HDL, were also up-regulated by dietary HEG.

CONCLUSIONS

These results suggest that HEG ameliorates plasma lipid profiles and attenuates hepatic lipid accumulation in the high-fat fed rats. Our findings provides that the effects of HEG on the increase of the plasma HDL-C level was at least partially mediated by up-regulation of hepatic genes expression such as apoA-I, ABCA1, and LCAT in rats fed a high-fat diet.

Determination of D-pinitol in carob syrup

Carob syrup is a traditional product native to the Mediterranean region, containing a high concentration of sugar, phenolic compounds and minerals. d-pinitol is a bioactive component extracted from legumes and has some beneficial effects on human metabolism. In this research, the d-pinitol content and sugar profile of 10 different carob syrup samples purchased from Turkish markets were determined. Mean d-pinitol, sucrose, glucose and fructose contents of samples were found to be 84.63 ± 10.73, 385.90 ± 45.07, 152.44 ± 21.72 and 162.03 ± 21.45 g/kg dry weight, respectively. Carob syrup has a considerable amount of d-pinitol compared with the other d-pinitol-including legumes. Consequently, this study showed that carob syrup may be a suitable source of d-pinitol for medical use and d-pinitol may be an indicator for the detection of any adulteration in carob syrup.