Hypolipidemic and antioxidant effects of dietary fenugreek (Trigonella foenum-graecum) seeds and garlic (Allium sativum) in high-fat fed rats

Phenolic Profiling, In Vitro Antiglycation, Antioxidant Activities, and Antidiabetic Effect of Algerian Trigonella Foenum-Graecum L. in Rats Administered a β-Cell Toxicant

This study sought to quantitatively assess individual and total polyphenols, mineral composition, antioxidant and antiglycation activities of Algerian fenugreek seeds (AFS) as well as the antidiabetic effect of its supplementation on streptozotocin-induced diabetic rats. Forty rats were divided into four groups (i) non diabetic rats, (ii) non diabetic rats +10 % AFS, (iii) diabetic rats, (iv) diabetic rats +10 % AFS. Flame-SAA analysis revealed a rich content in micro-elements, HPLC DAD-FLD analysis revealed twenty components with rutin and ferulic acid being the major compounds in AFS hydro-methanolic extract while spectrophotometric assays scrutinized moderate contents in total phenolics and flavonoids. The extract was potent in scavenging ABTS⋅+ and DPPH+ (42.06±2.14 and 55.84±4.14 mg TE/g), reducing Fe3+ and Mo6+ (35.12±2.45 and 29.89±3.12 mg TE/g) and inhibiting AGEs (IC50=1.03±0.02 mg/ml). In vivo, 10 %AFS- supplemented diet (w/w) was found to elicit a significant reduction in glycemia (66.74 %), TNF α (9.4 %), IL-6 (23.74 %), CRP (31.10 %), liver enzymes, lipid peroxidation (MDA) (47.24 %;30 %), protein carbonyl (PCO) (28.35 %; 27.15 %), improvement in insulin level (79.74 %), reduced glutathione amount (GSH) (41.01 %; 16.55 %), glutathione peroxidase (GPx) (45.80 %; 56.37 %), catalase (CAT) (24.44 %; 35.42 %) and glutathione-S-transferase (GST) (22.78 %; 22.90 %) activities, in liver and pancreas respectively, along with a rejuvenation of hepatic and pancreatic histological features. These outcomes disclosed that AFS is endowed with biologically effective components which could be decent applicant to attain the objective of mitigating glycation, oxidative stress and diabetes-related complications.

Two novel angiotensin I-converting enzyme inhibitory peptides from garlic protein: In silico screening, stability, antihypertensive effects in vivo and underlying mechanisms

This study aimed to screen novel angiotensin I-converting enzyme (ACE) inhibitory peptides from garlic proteins and to explore their underlying antihypertensive mechanisms in vivo. After simulated hydrolysis and in silico screening, two novel peptides (MGR and HDCF) were obtained with the highest ACE inhibitory activity (IC50 of 4.50 μM and 26.38 μM) and acted as competitive inhibitors. They interacted with key residues in the ACE receptor mainly through hydrogen bonding and exhibited excellent stability against high temperature, extreme pH, and gastrointestinal digestion. In spontaneously hypertensive rats, MGR and HDCF effectively lowered blood pressure after single or continuous treatments. This was mainly achieved by balancing the renin-angiotensin system, improving renal and cardiac impairment, and regulating endothelial dysfunction. These findings suggested that garlic proteins were potentially suitable materials to prepare ACE inhibitory peptides and provided two promising candidates for ACE inhibition as functional food ingredients.

Flavonoids from Rosa davurica Pall. fruits prevent high-fat diet-induced obesity and liver injury via modulation of the gut microbiota in mice

Rosa davurica Pall. (RDP) fruits are popularly consumed as beverages and healthy food in China because of their various beneficial activities. In particular, flavonoids are one of the major active ingredients of RDP fruits with predominant pharmacological effects. However, the anti-obesity activities of flavonoids from RDP fruits and their regulation effect on the gut microbiota have not been determined. In the present study, the flavonoid-rich extracts (RDPF) were isolated from RDP fruits and their anti-obesity effects were investigated using a high-fat diet (HFD)-induced obese mouse model. The results showed that RDPF intervention significantly inhibited the body weight, liver weight, kidney weight and epididymal adipose tissue weight of HFD-fed mice without affecting the calorie intake. Plasma lipid levels were also significantly lowered by RDPF treatment. Histological examination showed that RDPF supplementation partially recovered HFD-induced hepatic steatosis in the liver. RDPF also prevented oxidative injury of the liver, as evidenced by the altered superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels. The expression levels of CCAAT/enhancer binding protein α (C/EBPα), sterol regulatory element binding protein-1C (SREBP-1C), fatty acid synthase (FAS), acyl-coenzyme A oxidase 1 (ACOX1), peroxisome proliferator-activated receptor (PPARα) and CAT mRNA in the livers of mice were also regulated by RDPF administration. 16S rRNA gene sequence data further indicated that RDPF addition increased the microbial diversity and reshaped the community composition. Intriguingly, RDPF intervention did not exhibit inhibitory tendency toward the ratio of Firmicutes to Bacteroidetes, but markedly decreased the relative abundance of Erysipelotrichaceae. This study provided novel insights into the application of RDPF in the food industry.

Polysaccharide from Flammulina velutipes attenuates markers of metabolic syndrome by modulating the gut microbiota and lipid metabolism in high fat diet-fed mice

Natural biological macromolecules with putative functions of gut microbiota regulation possess the advantage of improving metabolic syndrome (MS). In this research, we aimed to determine the effects of Flammulina velutipes polysaccharide (FVP) (Expt. 1) and fecal microbiota transplantation (FMT) (Expt. 2) on MS-related disorders, gut microbiota structure changes and their underlying mechanisms in a murine model fed with high-fat diet (HFD). In Expt. 1, six-week-old male C57BL/6J mice were fed with a control diet (10% calories from fat) or a high fat diet (45% calories from fat), administered with saline or FVP (0.4 mg per g b.w.) by gavage over a 12-week period. In Expt. 2, mice were fed with a HFD, administered with fecal supernatants from healthy and FVP-fed donor mice for 12 weeks simultaneously. The body mass, blood lipid levels and blood glucose homeostasis of mice were analyzed, and total RNA from mouse liver and adipose tissue were extracted by TRIzol and the lipid metabolism-related gene expressions were calculated by qRT-PCR. Gut microbiota changes were evaluated by high-throughput sequencing. Results indicated that FVP and FMT supplementations showed an attenuation effect on mouse obesity, hyperlipidemia and insulin resistance. Up-regulated expressions of Ampkα1 and Ppara were found both in FVP and FMT treatment groups. Different changes were found in the gut microbiota caused by FVP and FMT, respectively. PICRUSt analysis indicated that compared with FVP supplementation, FMT showed a significant effect on regulating lipid metabolism in HFD-fed mice. The findings from this study indicated that oral administrations of FVP or FMT could significantly attenuate MS-related obesity, hyperlipidemia and insulin resistance in HFD-fed mice, and the beneficial effects may be mediated through lipid metabolism and gut microbiota regulation in different ways. These results improve the understanding of the functional activity of FVP as prebiotics.

Comparison of ultrasound and microwave assisted extraction of diosgenin from Trigonella foenum graceum seed

From the recent market trend, there is a huge demand for the bioactive compounds from various food matrices that could be capable enough to combat the emerging health effects in day-to-day life. Fenugreek is a well-known spice from ancient times for its medicinal and health benefits. In the present study, two methods of green extraction microwave (MAE) and ultrasound (UAE) assisted were studied in regard of extraction of fenugreek diosgenin. In this study, solvent type (acetone, ethanol, hexane and petroleum ether), solvent concentration (40, 60, 80 and 100%) and treatment time (1.5, 3.0, 4.5 and 6.0 min and 30, 40, 50 and 60 min for MAE and UAE method respectively) was varied to observe the effect of these parameters over extract yield and diosgenin content. The results of this study revealed that treatment time, type of solvent and its concentration and method adopted for extraction of diosgenin has significant effect. In relation with better yield extract and diosgenin content, the yield of fenugreek seed extract was 7.83% with MAE and 21.48% with UAE of fenugreek seed powder at 80% ethanol concentration at 6 and 60 min respectively. The content of diosgenin was observed in fenugreek seed powder extract was 35.50 mg/100 g in MAE and 40.37 mg/100 g in UAE with 80% ethanol concentration at 6 and 60 min respectively. The overall range of yield of fenugreek extract was varied from 1.04% to 32.48% and diosgenin content was 15.82 mg/100 g to 40.37 mg/100 g of fenugreek seed powder including both extraction methods. This study revealed that UAE would impose better ways for preparing fenugreek extract and observing diosgenin content from fenugreek seeds.

Physico-Chemical Analysis and Fatty Acid Profiling of Fenugreek (Trigonella foenum-graecum) Seed Oil Using Different Solvents

Fenugreek (Trigonella foenum-graecum) a native to Southern Europe, Mediterranean region and Western Asia has been used as a spice all over the world to increase the sensory quality to the food. It is also known for its medicinal properties such as anti-diabetic, anti-carcinogenic, hypocholesterolemic and immunological activities and can also be used as a food stabilizer and emulsifying agent. The ash, protein, moisture and fiber content of defatted fenugreek seed powder obtained were 9%, 23.04%, 3.8%, 25.47% respectively. So, this study is systematically intended to determine the fatty acid composition, to be best among the different solvents used are the ethanol, petroleum ether, acetone and hexane for the extraction of the fenugreek seed oil and to analyze its susceptibility to oxidation. This study was carried out to investigate and examine the results such as acid value, peroxide value, saponification value, iodine value and the physical properties such as the color value and the refractive index of the seed oil. The results stipulate that the oil extracted using the solvent hexane had better quality and yield. Linoleic acid (41.97%) followed by alpha-linolenic acid (29.33%) and cis-9 oleic acid (12.95%) was found as the primary fatty acids present in the oil extracted using hexane. Along with these fatty acids, the PUFA content of hexane oil (71.30%) was also observed to be in a good range. So, on comparing these results with codex standards, it revealed that it can be considered as edible oil with further purifications.

Single garlic oil modulates T cells activation and proinflammatory cytokine in mice with high fat diet

BACKGROUND

Hyperlipidemia triggers atherosclerosis by involving immune cells, such as T-cells. T-cells plays a role in worsening conditions during a high-fat diet (HFD).

OBJECTIVE

The research aimed to analyze the role of single garlic oil (SGO) on T-cells activation and its proinflammatory cytokine expression in HFD mice.

METHODS

Mice were divided into six groups: ND (normal diet); HFD (high-fat diet without treatment); HFD + Simv (HFD + simvastatin 2.6 mg/kg body weight); and HFD + SGO 1-3 (high-fat diet + single garlic oil in a dose of 12.5, 25, and 50 mg/kg body weight), respectively. Treatments were orally given every day for 45 days. At the end of treatments, lymphocytes were isolated from mice spleen. The relative number of T-cells and proinflammatory cytokines were measured using flow-cytometry and analyzed using one-way ANOVA (p < 0.05).

RESULT

Our result indicated that HFD mice had lower naive T cells (CD4+CD62L+) than normal mice (p < 0.05). SGO treatment in HFD mice increased the relative number of naïve T cells. HFD treatment increased the expression of TNF-α and IFN-γ through NF-κB expression. Furthermore, SGO treatment improved the expression of TNF-α and IFN-γ.

CONCLUSION

Our study suggests that SGO could act as a promising prospect for therapy to improve chronic inflammation in a HFD.

A combined healthy strategy for successful weight loss, weight maintenance and improvement of hepatic lipid metabolism

Obesity is critically related with the development of metabolic and pathophysiological alterations among which non-alcoholic fatty liver disease (NAFLD) is of especial relevance. Although there are numerous strategies to successfully treat obesity, the prevention of weight regain still remains challenging for individuals who have undergone weight loss programs. In such context, diet and physical activity are considered essential for the regulation of body weight and lipid metabolism. In this study, rats were fed a high-fat diet (HFD) to induce obesity and alterations in hepatic lipid metabolism. Obese rats were then treated with single or combined strategies of caloric restriction, physical exercise, and/or pharmacological treatment with an appetite suppressant, to lose weight, reverse the obesity-related alterations in hepatic morphology and lipid metabolism and maintain the beneficial effects of the interventions used. HFD induced excess body weight, hepatic steatosis, altered fatty acid profile, dysregulated gene expression of lipogenic and lipolytic enzymes, as well as plasma markers of liver damage, and modifications in liver antioxidant enzyme activity. Such alterations were ameliorated by caloric restriction in combination with a mixed training protocol and/or food-intake inhibitor administration during a weight loss intervention period of 3 weeks, and the beneficial effects remained after 6 weeks of weight maintenance, with some interesting interactions observed. In conclusion, weight loss strategies assayed were efficient at correcting the obesogenic action of a HFD and related alterations in hepatic functionality through different molecular mechanisms. The beneficial effects were also evident along the post-intervention maintenance period to avoid body weight regain.

Tea Polysaccharides as Potential Therapeutic Options for Metabolic Diseases

Tea polysaccharides (TPS) are regarded as some of the main bioactive constituents of tea made from the leaves and buds of the tea plant ( Camellia sinensis L.). An increasing number of studies have demonstrated that TPS can reduce the risk of type 2 diabetes, obesity, and other metabolic diseases. However, the potential mechanisms responsible for antidiabetic and antiobesogenic activities of TPS remain unclear. Therefore, the cellular and physiological mechanisms that underlie the antidiabetic and antiobesogenic effects, including antioxidant and anti-inflammation effects, inhibition of digestive enzymes, prevention of macronutrient absorption, and expression of gene and protein, were summarized in this review. Furthermore, the gastrointestinal functions of TPS and the role of gut microbiota in the prevention and treatment of metabolic diseases were discussed. It is expected that the present review will be helpful for enhancing our knowledge about the health-promoting effects of TPS on metabolic diseases and stimulating further works on TPS.

Evaluation of chemical property, cytotoxicity and antioxidant activity in vitro and in vivo of polysaccharides from Fuzhuan brick teas

Fuzhuan brick tea (FBT) possesses various health-promoting functions. However, the available information regarding biological activity of polysaccharides from FBT (FBTPS) is still limited. In this work, the chemical property, cytotoxicity and antioxidant activity in vitro and in vivo of FBTPS were evaluated. It was found that FBTPSs were typical acidic heteropolysaccharides mainly composed of Man, Rha, GalA, Glc, Gal and Ara with little molar content of Rib and GlcA. FBTPS showed little toxicity to human hepatic epithelial (L-02) cell. FBTPS exhibited antioxidant activities, including limited scavenging activity on DPPH free radicals (ranged from 54.3 ± 1.9 to 67.8 ± 2.5%), noticeable scavenging activity on superoxide radicals (over 85%), superior scavenging activity on ABTS radicals (near 100%), and protective effect on H₂O₂-induced oxidative injury in rat pheochromocytoma line 12 (PC12) cell. Moreover, FBTPS showed significant amelioration of high-fat diet-induced oxidative injury in mice. The results suggest that FBTPS, as natural safe antioxidants, may have potential application in functional foods.

Comparison the Effects of Trigonella foenum-graecum L. Seed and Cordia myxa Fruit Extracts on DiabetesInduced Memory Impairment in Rats

Introduction: Trigonella foenum-graecum L. (Fenugreek) seeds and Cordia myxa fruits have been known as agents with anti-diabetes effects in Iranian traditional medicine. We compared the effects of aqueous extracts of these plants on diabetes-induced cognitive dysfunction. Methods: In our study, rats were equally allocated to 4 groups (n=12/group) as follows: control; diabetic; diabetic rats treated with T. foenum graecum seeds extract (TE) (870 mg/kg BW); and diabetic rats treated with C. myxa fruit extract (CE) (500 mg/kg BW) for 30 days. Diabetes was induced by alloxan (120 mg/kg BW, ip). Cognitive dysfunction was determined through memory task and passive avoidance learning (PAL). Results: Diabetes resulted in cognitive impairment in PAL and memory task. CE and TE significantly reduced serum blood sugar (P<0.05) and brain lipid peroxidation (P<0.001). Moreover, treatment with both extracts prohibited learning and memory deficits in diabetic groups in comparison to the non-treated group; however, there was no significant difference between the groups that were treated with TE or CE. Conclusion: Aqueous extract of fenugreek seeds and C. myxa are effective in preventing diabetesinduced lipid peroxidation and memory loss in animal models of diabetes.

Molecular understanding of the protective role of natural products on isoproterenol-induced myocardial infarction: A review

Modern medicine has been used to treat myocardial infarction, a subset of cardiovascular diseases, and have been relatively effective but not without adverse effects. Consequently, this issue has stimulated interest in the use of natural products, which may be equally effective and better tolerated. Many studies have investigated the cardioprotective effect of natural products, such as plant-derived phytochemicals, against isoproterenol (ISO)-induced myocardial damage; these have produced promising results on the basis of their antioxidant, anti-atherosclerotic, anti-apoptotic and anti-inflammatory activities. This review briefly introduces the pathophysiology of myocardial infarction (MI) and then addresses the progress of natural product research towards its treatment. We highlight the promising applications and mechanisms of action of plant extracts, phytochemicals and polyherbal formulations towards the treatment of ISO-induced myocardial damage. Most of the products displayed elevated antioxidant levels with decreased oxidative stress and lipid peroxidation, along with restoration of ionic balance and lowered expression of myocardial injury markers, pro-inflammatory cytokines, and apoptotic parameters. Likewise, lipid profiles were positively altered and histopathological improvements could be seen from, for example, the better membrane integrity, decreased necrosis, edema, infarct size, and leukocyte infiltration. This review highlights promising results towards the amelioration of ISO-induced myocardial damage, which suggest the direction for future research on natural products that could be used to treat MI.

Hypolipidemic effect of Youcha in hyperlipidemia rats induced by high-fat diet

Youcha is a novel tea drink from the northeast of Guangxi. This study aimed to investigate the hypolipidemic properties of Youcha in high-fat induced hyperlipidemic Sprague-Dawley (SD) rats. After designing the model, rats were randomly divided into six groups (n = 10): normal diet (NMD) group, high-fat diet (HFD) group, Xuezhikang (120 mg kg-1 d-1) (HFD+P) group and Youcha (150, 750 or 1500 mg kg-1 d-1) (HFD+L, HFD+M or HFD+H) groups. Youcha comprises tea polyphenols (1.51 g per 100 g), caffeine (34.80 mg per 100 g) and other functional compounds. To evaluate the lipid-lowering effects of Youcha, weight of the body, liver and fat, fat index, lipid metabolism, antioxidant properties and liver damage indices were examined. In addition, the activities of some enzymes in serum and liver tissue were examined to preliminarily study their possible mechanism. The results reveal that Youcha tends to reduce body weight, liver weight, fat index, total cholesterol (TC) and triglyceride (TG) contents, low-density lipoprotein cholesterol (LDL-C), atherogenic index (AI), malondialdehyde (MDA), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and increase high-density lipoprotein cholesterol (HDL-C), superoxide dismutase (SOD) and glutathione peroxidase (GPx) relative to the HFD group. The hypolipidemic effect was partly due to the regulation of fatty acid synthetase (FAS) and lipase (LPS) rather than lipoprotein lipase (LPL) to decrease TG markedly. These findings suggest that Youcha could be potentially used to remedy hyperlipidemia and is hence worthy of promotion as a tea drink.

Hypolipidemic effect of β-caryophyllene to treat hyperlipidemic rats

The aim of this study was to evaluate the effect of β-caryophyllene on hypercholesterolemia using a model of hyperlipidemia induced by Triton WR-1339 in rats, as well as its possible effect on hepatic antioxidant enzymes. Thus, total cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol were measured in serum, while reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), hepatic 3-hydroxy-3-methylglutayl coenzyme A (HMG-CoA) reductase, superoxide dismutase (SOD), and catalase (CAT) activities were measured in the hepatic tissue. In addition, seric concentrations of β-caryophyllene were measured to perform correlation studies. Serum samples from hypercholesterolemic rats show higher (p < 0.05) levels of total cholesterol, triglycerides, and LDL cholesterol, and lower (p < 0.05) levels of HDL cholesterol compared to non-hypercholesterolemic rats. β-Caryophyllene treatment reduced (p < 0.05) the levels of total cholesterol, triglycerides and LDL cholesterol, similar to the reference drug simvastatin. However, HDL cholesterol levels did not increase with the treatment. β-Caryophyllene treatment was able to inhibit the HMG-CoA reductase activity, as well as to prevent the increase on ROS and TBARS levels, and ameliorate the antioxidant system. In summary, our findings demonstrated that β-caryophyllene has hypolipidemic effect via inhibition of the hepatic HMG-CoA reductase, like the standard drug simvastatin, and this inhibition suggests a possible mechanism of hypolipidemic action. Thus, our results indicate that β-caryophyllene can be used to treat dyslipidemic diseases because it exerts a similar effect as the reference drug, protecting the liver against lipid damage and improving the hepatic antioxidant defense system.