Garlic essential oil protects against obesity-triggered nonalcoholic fatty liver disease through modulation of lipid metabolism and oxidative stress

Diet-Derived Phytochemicals Targeting Colon Cancer Stem Cells and Microbiota in Colorectal Cancer

Colorectal cancer (CRC) is a fatal disease caused by the uncontrolled propagation and endurance of atypical colon cells. A person's lifestyle and eating pattern have significant impacts on the CRC in a positive and/or negative way. Diet-derived phytochemicals modulate the microbiome as well as targeting colon cancer stem cells (CSCs) that are found to offer significant protective effects against CRC, which were organized in an appropriate spot on the paper. All information on dietary phytochemicals, gut microbiome, CSCs, and their influence on CRC were accessed from the various databases and electronic search engines. The effectiveness of CRC can be reduced using various dietary phytochemicals or modulating microbiome that reduces or inverses the progression of a tumor as well as CSCs, which could be a promising and efficient way to reduce the burden of CRC. Phytochemicals with modulation of gut microbiome continue to be auspicious investigations in CRC through noticeable anti-tumorigenic effects and goals to CSCs, which provides new openings for cancer inhibition and treatment.

Potential application of nanoemulsified garlic oil blend in mitigating the progression of type 2 diabetes-mediated nephropathy in Wistar rats

The renoprotective potential of nanoemulsified garlic oil blend (GNE) in alleviating the progressive stages of hyperlipidemia-mediated diabetic nephropathy was examined. The study was carried out in high fat-fed, streptozotocin-induced type 2 diabetic Wistar rats for five months. The diabetic rats showed a significant increase of area under the curve in OGTT (p < 0.01) and IPITT (p < 0.01), increased urinary albumin (p < 0.01), urinary microprotein (p < 0.001), total cholesterol (p < 0.01), triglycerides (p < 0.001) and LDL cholesterol (p < 0.001), with decreased serum albumin (p < 0.01), serum protein (p < 0.001) and HDL-cholesterol levels (p < 0.05) than the control rats. The histopathological analysis evidenced mesangial expansion and hypercellularity at the end of the first and third month, and glomerulosclerosis and tubular atrophy at the end of the fifth month in diabetic rats. Moreover, on disease progression, increase in urinary podocalyxin, NGAL and CD36 was observed, and the renal mRNA and protein expression of podocalyxin decreased significantly with a concomitant increase in NGAL and CD36 expression from first till fifth month end. The treatment with GNE (20 mg/kg) significantly ameliorated the serum albumin (p < 0.001) and urine albumin (p < 0.01) from the end of the third month with significant attenuation in the lipid profile than GO (20 mg/kg) or Ator (8 mg/kg). Moreover, GNE reverted the histopathological alterations and attenuated the aberrant mRNA, protein expression and urinary excretion level of renal CD36, podocalyxin and NGAL in diabetic rats from an early stage of disease till the end of the study period. This study demonstrated the enhanced efficacy of GO in nanoemulsified form in mitigating the progression of nephropathy in type 2 diabetic rats.

Allicin Regulates Energy Homeostasis through Brown Adipose Tissue

Brown adipose tissue (BAT) is a promising potential therapeutic target for the treatment of obesity and related metabolic diseases. Allicin, a natural product in garlic, has multiple biological and pharmacological functions. However, the role of allicin in the regulation of metabolic organs, particularly BAT activation, has not been well studied. Here, we show that allicin imparts a significant effect by inhibiting body weight gain, decreasing adiposity, maintaining glucose homeostasis, improving insulin resistance, and ameliorating hepatic steatosis in obese mice. These observations strongly correlate with the activation of BAT. Notably, allicin plays a role in BAT activation, which may partly contribute to the Sirt1-PGC1α-Tfam pathway. In addition, allicin can significantly increase the succinylation levels of UCP1 in BAT by inhibiting sirt5, whereas excess allicin induces autophagy/mitophagy and mitochondrial dysfunction. Thus, our findings point to allicin as a promising therapeutic approach for the treatment of obesity and metabolic disorders.

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Allicin reduces adiposity and maintains glucose homeostasis

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Allicin activates the brown adipocytes and increases the energy expenditure

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Allicin enhances BAT activity partly through SIRT1-PGC1a-Tfam signaling pathway

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Allicin regulates mitophagy via suppressed sirt5-mediated succinylation accumulation

Garlic essential oil mediates acute and chronic mild stress-induced depression in rats via modulation of monoaminergic neurotransmission and brain-derived neurotrophic factor levels

Garlic essential oil (GEO) and its major organosulfur component (diallyl disulfide, DADS) possess diverse biological properties; however, limited information on their antidepressant-like effects is available. This study is the first to investigate these effects of GEO using the forced swimming test (FST) and unpredictable chronic mild stress (UCMS) induced depression in rats. After oral administration for 28 consecutive days, GEO (25 and 50 mg per kg bw) significantly reduced the immobility time in the FST. Additionally, GEO and DADS significantly reversed the sucrose preference index decrease induced by 5 weeks of UCMS. GEO (25 mg per kg bw) effectively decreased the frontal cortex turnover ratio of serotonin (5-HT) and dopamine (DA), thus increasing the 5-HT and DA levels, with no hippocampal effects. Chronic GEO treatment increased hippocampal brain-derived neurotrophic factor (BDNF), c-AMP response element binding protein (CREB), and protein kinase B (AKT) expression, exhibiting its effects via monoamine neurotransmitter modulation and the BDNF-related signaling pathway.

Beneficial effects of Chinese herbs in the treatment of fatty liver diseases

Eating habits and lifestyle directly impact general health. Consumption of fat- and sugar-rich foods and alcohol increase the risk of developing fatty liver disease. The prevalence of fatty liver disease is markedly critical, and its pathogenesis and progression are complicated. Chinese herbal medicine has been used to treat and prevent human diseases through-out history, and is a rich source of biologically active substances with unique curative properties. More recently, Chinese herbs and their extracts have been identified as a novel source of potential therapeutic agents in the prevention and treatment of fatty liver disease. Beneficial effects of these herbal medicines mean that they can be classified as novel candidates for the treatment and prevention of both alcoholic fatty liver disease (AFLD) and non-alcoholic fatty liver disease (NAFLD), in place of conventional allopathic treatments. In this review, we explore the current literature related to herbal medicines used for the treatment of or protection against fatty liver diseases and describe their mechanisms of action.

Therapeutic Effects of Garlic on Hepatic Steatosis in Nonalcoholic Fatty Liver Disease Patients: A Randomized Clinical Trial

BACKGROUND AND AIMS

Emerging evidence suggests that garlic (Allium sativum L.) and its bioactive components can mitigate hepatic steatosis by the modulation of hepatic lipid metabolism. We aimed to assess the efficacy of the garlic administration on hepatic steatosis in patients with NAFLD.

PATIENTS AND METHODS

This clinical trial was conducted on adult patients with ultrasound-diagnosed NAFLD. Eligible participants were randomly assigned, with the use of the stratified blocked procedure, to receive 800 mg garlic or placebo for 15 weeks. The primary outcome was the improvement in the hepatic steatosis diagnosed by ultrasound technique after 15 weeks of intervention.

RESULTS

A total of 110 patients underwent randomization, and 98 patients completed the trial. Twenty-four (51.1%) patients in the garlic group achieved improvement in the hepatic steatosis compared to eight (15.7%) patients in the placebo group with the relative risk of 5.6 (95% CI: 2.17 to 14.5; P=0.001), which remained significant after adjusting for baseline value of hepatic steatosis. There were significant reductions in weight and serum ALT, AST, FBS, Hb A1C, total cholesterol, LDL-cholesterol, and TG concentration with the garlic intake compared to placebo (P<0.05). The results were also significant after adjusting for weight change, energy intake, and physical activity. No serious adverse effects were observed with the garlic intake.

CONCLUSION

The intake of garlic powder was accompanied by a significant improvement in the hepatic steatosis and comorbidity related to this condition among subjects with NAFLD.

Nonalcoholic Fatty Liver Disease Induced by High-Fat Diet in C57bl/6 Models

Researchers have a range of animal models in which to study Nonalcoholic fatty liver disease (NAFLD). Induction of NAFLD by a high-fat diet in the C57BL/6 strain is the most widely used among mice. In this study, we review works that performed NAFLD induction by a high-fat diet using the C57BL/6 strain, focusing on experiments on the effects of lipid ingestion. Studies are initially distinguished into researches in which mice received lipids by oral gavage and studies in which lipid was added to the diet, and each of these designs has peculiarities that must be considered. Oral gavage can be stressful for animals and needs trained handlers but allows accurate control of the dose administered. The addition of oils to the diet can prevent stress caused to mice by gavage, but possible changes in the consistency, taste, and smell of the diet should be considered. Regarding the experimental design, some variables, such as animal sex, treatment time, and diet-related variables, appear to have a definite pattern. However, no pattern was found regarding the number of animals per group, age at the beginning of the experiment, time of adaptation, the substance used as a vehicle, and substance used as a control.

Fatty liver and alteration of the gut microbiome induced by diallyl disulfide

Diallyl disulfide (DADS) is one of the primary components of garlic and it exhibits a broad range of biological activities. In the present study, the effects of DADS on lipid metabolism and its potential role in the modulation of the gut microbiome were determined. Hematoxylin and eosin and oil-red O staining were used to assess the liver and intestinal tissues of mice treated with DADS. The expression of lipid metabolism-associated genes was measured using reverse transcription-quantitative PCR (RT-qPCR). The effects of DADS on the gut microbiome were measured using 16S recombinant (r)DNA gene analysis. The results revealed that the serum non-esterified free fatty acids, high density lipopro-tein-cholesterol, low density lipoprotein-cholesterol, serum total cholesterol, liver triglyceride and total cholesterol levels of the mice fed with a low-dose of DADS was significantly higher when compared with the control. Hematoxylin and eosin and oil-red O staining demonstrated that DADS induced fatty liver in mice. The results of the RT-qPCR revealed that the expression levels of a number of lipid metabolism-associated genes were altered in the livers of mice treated with DADS.

The 16S rDNA gene analysis demonstrated that the mice fed on a normal diet treated with a low-dose of DADS had decreased levels of bacteria from the Bacteroidetes phyla and increased levels of bacteria from the Firmicutes phyla. The Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed the top 20 pathways enriched in the low-dose DADS group of mice fed with a normal diet. In the present study, low-dose DADS induced fatty liver and altered the gut micro-biota, similar to the phenotype induced by a high fat diet, by regulating the expression of lipid metabolism associated genes.

Hepatoprotective and Renoprotective Properties of Lovastatin-Loaded Ginger and Garlic Oil Nanoemulsomes: Insights into Serum Biological Parameters

Background and Objectives: Dyslipidemia is gaining much attention among healthcare professionals because of its high association with the malfunctioning of a number of normal physiological and metabolic processes in the body. Obesity is directly interconnected with dyslipidemia and is said to be a denouement of hyperlipidemia and, if left untreated, may lead to intense damage to organs that are directly involved in fat metabolism. The objective of this study was to investigate the synergistic antiobesity and anti-hyperlipidemic activities along with hepato- and renoprotective potential of nanoemulsomes (NES) of lovastatin (LTN)-loaded ginger (GR) and garlic (GL) oils. Materials and Methods: LTN nanoemulsomes co-encapsulated with GR oil and GL oil were prepared by a thin hydration technique. Eight-week-old male Wistar rats weighing 200-250 g were induced with hyperlipidemia via a high-fat diet (HFD) comprising 40% beef tallow. Body weight, serum biochemical lipid parameters, and those for liver and kidney functions, serum TC, LDL-C, vLDL-C, HDL-C, TG, atherogenic index (AI), ALT, AFT, ALP, γ-GT, total protein (TP), serum albumin and globulin ratio (A/G), serum creatinine, blood urea nitrogen (BUN) and blood urea, and histopathology of hematoxylin and eosin (H&E) stained liver and kidney sections of all aforementioned groups were examined in the treated animals. Results: Nanoemulsomes of LTN-loaded GR and GL oils provided synergistic effects with LTN, exerted better ameliorative actions in reducing serum TC, LDL-C, vLDL-C, triglycerides, and AI, and improved serum HDL-C levels. Serum ALT, AST, ALP, and γ-GT levels were in the normal range for nanoemulsome groups. H&E stained liver and kidney sections of these animals confirmed better hepatoprotective and renoprotective effects than LTN alone. Serum biochemical parameters for renal functions also claimed to be in the moderate range for nanoemulsome-treated groups. Conclusion: This study demonstrated that nanoemulsomes of LTN-loaded GR and GL oils synergistically provided better antihyperlipidemic, hepatoprotective, and renoprotective effects as compared to LTN alone.

Correlation of the rumen fluid microbiome and the average daily gain with a dietary supplementation of Allium mongolicum Regel extracts in sheep1

Plant extracts can affect the rumen microbiome and ADG in ruminants, and studies of the association between the rumen microbiome and ADG provide information applicable to improving ruminant growth performance. The objectives were to investigate the effects of Allium mongolicum Regel extracts on the rumen microbiome and ADG and their association in sheep. Forty healthy, male, small-tailed Han sheep (6 mo, 34 ± 3.5 kg body weight) were randomly assigned to 1 of the following 4 dietary treatments: basal diet as control group (CK, n = 10), basal diet supplemented with 3.4 g·sheep-1·d-1A. mongolicum Regel powder extract as PAM group (PAM, n = 10), basal diet supplemented with 10 g·sheep-1·d-1A. mongolicum Regel powder as AM group (AM, n = 10), and basal diet supplemented with 10 g·sheep-1·d-1A. mongolicum Regel powder extract residue as RAM group (RAM, n = 10). The ADG for individual sheep was calculated using the sum of the ADGs observed during the experimental period divided by the number of days in the experimental period. At the end of the experiment, sheep were randomly selected from each treatment for slaughter (n = 6), and the rumen fluids were collected and stored immediately at -80 °C. Illumina HiSeq was subsequently used to investigate the changes in the rumen microbiome profile, and the associations with ADG were analyzed by Spearman correlation coefficient analysis. The results demonstrated that, compared with that in CK group, the ADG in AM and RAM significantly increased (P = 0.0171). The abundances of Tenericutes and Mollicutes ([ρ] = 0.5021, P = 0.0124) were positively correlated with ADG. Within Mollicutes, the abundances of Anaeroplasmatales ([ρ] = 0.5458, P = 0.0058) and Anaeroplasmataceae ([ρ] = 0.5458, P = 0.0058) were positively correlated with ADG. The main negatively correlated bacteria were Saccharibacteria ([ρ] = -0.4762, P = 0.0187) and Betaproteobacteria ([ρ] = -0.5669, P = 0.039). Although Anaeroplasmatales and Anaeroplasmataceae were positively correlated with ADG, Saccharibacteria and Betaproteobacteria were negatively correlated with ADG. In conclusion, supplementation with A. mongolicum Regel powder and extracts will influence the rumen microbiome and increase the ADG.

Bioactive Compounds and Biological Functions of Garlic (Allium sativum L.)

Garlic (Allium sativum L.) is a widely consumed spice in the world. Garlic contains diverse bioactive compounds, such as allicin, alliin, diallyl sulfide, diallyl disulfide, diallyl trisulfide, ajoene, and S-allyl-cysteine. Substantial studies have shown that garlic and its bioactive constituents exhibit antioxidant, anti-inflammatory, antibacterial, antifungal, immunomodulatory, cardiovascular protective, anticancer, hepatoprotective, digestive system protective, anti-diabetic, anti-obesity, neuroprotective, and renal protective properties. In this review, the main bioactive compounds and important biological functions of garlic are summarized, highlighting and discussing the relevant mechanisms of actions. Overall, garlic is an excellent natural source of bioactive sulfur-containing compounds and has promising applications in the development of functional foods or nutraceuticals for the prevention and management of certain diseases.

Bioactive Compounds and Biological Functions of Garlic (Allium sativum L.)

Garlic (Allium sativum L.) is a widely consumed spice in the world. Garlic contains diverse bioactive compounds, such as allicin, alliin, diallyl sulfide, diallyl disulfide, diallyl trisulfide, ajoene, and S-allyl-cysteine. Substantial studies have shown that garlic and its bioactive constituents exhibit antioxidant, anti-inflammatory, antibacterial, antifungal, immunomodulatory, cardiovascular protective, anticancer, hepatoprotective, digestive system protective, anti-diabetic, anti-obesity, neuroprotective, and renal protective properties. In this review, the main bioactive compounds and important biological functions of garlic are summarized, highlighting and discussing the relevant mechanisms of actions. Overall, garlic is an excellent natural source of bioactive sulfur-containing compounds and has promising applications in the development of functional foods or nutraceuticals for the prevention and management of certain diseases.

Cold-pressed Canola Oil Reduces Hepatic Steatosis by Modulating Oxidative Stress and Lipid Metabolism in KM Mice Compared with Refined Bleached Deodorized Canola Oil

The quality of canola oil is affected by different extraction methods. The effect of cold-pressed canola oil (CPCO) diet and traditional refined bleached deodorized canola oil (RBDCO) diet on lipid accumulation and hepatic steatosis in mice were investigated. The body weight, peroxisome proliferator-activated receptor-α concentration, serum lipid profile, insulin sensitivity, and oxidative stress were increased in mice fed with CPCO diet, which had higher unsaturated fatty acid, tocopherols, phytosterols, and phospholipids but lower saturated fatty acid than RBDCO, after 12 weeks,. Moreover, CPCO significantly increased tocopherols and phytosterols content in liver and reduced liver cholesterol contents and lipid vacuoles accumulation than RBDCO. Also, serum proinflammatory cytokines, 3-hydroxy-3-methylglutary coenzyme A reductase expression level, lipogenic enzymes, and transcriptional factors such as sterol regulatory element-binding proteins 1c, acetyl-CoA carboxylase, and fatty acid synthase in the liver were also markedly downregulated from CPCO diet mice. Overall, CPCO can reduce lipid accumulation and hepatic steatosis by regulating oxidative stress and lipid metabolism in Kun Ming mice compared with RBDCO. PRACTICAL APPLICATION: The results suggested that more bioactive components were contained in cold-pressed canola oil (CPCO) rather than refined bleached deodorized canola oil (RBDCO). CPCO could lower the risk of obesity and hyperlipidemia, reduce lipid accumulation, and prevent hepatic steatosis. It could be considered as a kind of better edible oil than RBDCO.

Diallyl disulfide attenuates non‑alcoholic steatohepatitis by suppressing key regulators of lipid metabolism, lipid peroxidation and inflammation in mice

Non‑alcoholic steatohepatitis (NASH) is a common clinicopathological condition. Currently, the pathogenesis of NASH remains unknown, and no optimal therapy option currently exists. It has previously been demonstrated that diallyl disulfide (DADS) was capable of attenuating liver dysfunction, as DADS supplementation had a positive impact on liver regeneration, proliferation and oxidative damage. Thus, DADS could serve as a potential therapeutic agent that can protect against the effects of NASH. The present study aimed to evaluate the effect of DADS on NASH and to understand the associated underlying molecular mechanisms. A methionine‑ and choline‑deficient diet (MCD) and high‑fat diet (HFD) are the two common animal models that induce NASH. C57BL/6J mice were fed an MCD for 4 weeks, or an HFD for 20 weeks, in the present study. The mice were treated with or without DADS (20, 50 and 100 mg/kg) for 4 or 20 weeks. For the histopathological examination, hematoxylin and eosin staining, oil red O staining and immunohistochemical analyses were performed using the liver sections. Biochemical assays and ELISA were performed to measure the serum biochemical indicators of hepatic function and inflammatory indicators, respectively. Reverse transcription‑quantitative PCR, immunofluorescence and western blotting were used to detect expression levels of the genes involved in the molecular mechanisms underlying DADS protection. MCD or HFD induced the histological features of NASH in mice, including significant vacuolated hepatocytes, marked inflammatory cell infiltration and severe micro‑ and macro‑vesicular steatosis. Serum alanine transferase and aspartate aminotransferase levels, as well as the contents of liver triglyceride and total cholesterol, were significantly increased in these two models. DADS attenuated these histological and biochemical changes. DADS ameliorated hepatic steatosis by regulating sterol regulatory element‑binding transcription factor 1, apolipoprotein A1, cyclic AMP‑responsive element‑binding protein H and fibroblast growth factor 21. Furthermore, DADS was revealed to prevent lipotoxicity via peroxisome proliferator‑activated receptor α elevation and stearoyl‑coenzyme A desaturase 1 inhibition in HFD‑fed mice. In addition, DADS markedly inhibited lipid peroxidation by modulating malondialdehyde and superoxide dismutase, and it also decreased tumor necrosis factor‑α production, interleukin‑6 production and macrophage influx, as well as suppressing nuclear factor‑κB activation, indicating suppression of MCD‑induced hepatic inflammation. Taken together, the results have shown that DADS exerts beneficial effects on MCD‑ or HFD‑induced NASH by suppressing key regulators of lipid metabolism, lipid peroxidation and inflammation.

Enhanced Therapeutic Potency of Nanoemulsified Garlic Oil Blend Towards Renal Abnormalities in Pre-diabetic Rats

The therapeutic potency of ultrasonic nanoemulsified garlic oil blend using a non-ionic surfactant (Tween 80) was assessed on pre-diabetic Wistar rats with microalbuminuria. The pre-diabetic condition was induced in male albino Wistar rats by supplementing high-fat diet. The prolonged period of the pre-diabetic state caused renal dysfunctioning, which was indicated by microalbuminuria. Treatment of pre-diabetic rats with nanoemulsified garlic oil blend significantly ameliorated the lipid profile (p < 0.001), urinary albumin (p < 0.01), microprotein (p < 0.001), urinary triglycerides (p < 0.01), serum triglycerides (p < 0.01), serum albumin (p < 0.05), and protein levels (p < 0.01) in comparison to treatment of pre-diabetic rats with garlic oil blend or atorvastatin. Similarly, histopathological investigations indicated a remarkable attenuation in the mesangial expansion and proliferation, glomerular and tubular basement membrane thickening, and the tubular lipid deposits on administering nanoemulsified garlic oil blend than garlic oil blend or atorvastatin. Moreover, nanoemulsified garlic oil blend significantly promoted renal podocin gene expression by 3.98-fold (p < 0.001) and attenuated increased urinary podocin level by 2.92-fold (p < 0.01). Thus, our study affirms that the efficacy of garlic oil blend was augmented upon nanoemulsification, which substantially ameliorated the renal abnormalities observed in the pre-diabetic condition than garlic oil blend or atorvastatin.

Freshwater clam extract reduces liver injury by lowering cholesterol accumulation, improving dysregulated cholesterol synthesis and alleviating inflammation in high-fat, high-cholesterol and cholic acid diet-induced steatohepatitis in mice

Freshwater clam (Corbicula fluminea) is a traditional liver-protective food in Asia. Recent studies have renewed attention on high cholesterol accumulation and dysregulated cholesterol synthesis in the liver as a critical factor in the progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis (NASH). In this study, we investigated the protective effects of freshwater clam extract (FCE) and its fat fraction (FCE oil) on high-fat, high-cholesterol and cholic acid (HFHC) diet-induced lean steatohepatitis in mice. Mice were fed a HFHC diet containing FCE or FCE oil for 6 weeks. FCE, but not FCE oil, feeding reduced liver injury as indicated by decreased plasma alanine aminotransferase activity. Liver total cholesterol accumulation was reduced after FCE and FCE oil treatment. Accumulation of squalene and desmosterol, the precursors of cholesterol, in the liver was reduced by FCE but not by FCE oil. The caspase-1 (p10) and interleukin (IL)-1β (p17) protein expressions in the liver were suppressed by both FCE and FCE oil. Therefore, FCE may act as functional food that can reduce steatohepatitis and liver injury by reducing cholesterol accumulation, improving dysregulated cholesterol synthesis and attenuating inflammation.

Antioxidant and Oxidative Stress: A Mutual Interplay in Age-Related Diseases

Aging is the progressive loss of organ and tissue function over time. Growing older is positively linked to cognitive and biological degeneration such as physical frailty, psychological impairment, and cognitive decline. Oxidative stress is considered as an imbalance between pro- and antioxidant species, which results in molecular and cellular damage. Oxidative stress plays a crucial role in the development of age-related diseases. Emerging research evidence has suggested that antioxidant can control the autoxidation by interrupting the propagation of free radicals or by inhibiting the formation of free radicals and subsequently reduce oxidative stress, improve immune function, and increase healthy longevity. Indeed, oxidation damage is highly dependent on the inherited or acquired defects in enzymes involved in the redox-mediated signaling pathways. Therefore, the role of molecules with antioxidant activity that promote healthy aging and counteract oxidative stress is worth to discuss further. Of particular interest in this article, we highlighted the molecular mechanisms of antioxidants involved in the prevention of age-related diseases. Taken together, a better understanding of the role of antioxidants involved in redox modulation of inflammation would provide a useful approach for potential interventions, and subsequently promoting healthy longevity.

Potential Therapeutic Benefits of Herbs and Supplements in Patients with NAFLD

Our aim is to review the efficacy of various herbs and supplements as a possible therapeutic option in the treatment and/or prevention of nonalcoholic fatty liver disease (NAFLD). We performed a systematic review of medical literature using the PubMed Database by searching the chemical names of many common herbs and supplements with “AND (NAFLD or NASH)”. Studies and medical literature that discussed the roles and usage of herbs and supplements in NAFLD and nonalcoholic steatohepatitis (NASH) from inception until 20 June 2018 were reviewed. Many studies have claimed that the use of various herbs and supplements may improve disease endpoints and outcomes related to NAFLD and/or NASH. Improvement in liver function tests were noted. Amelioration or reduction of lobular inflammation, hepatic steatosis, and fibrosis were also noted. However, well-designed studies demonstrating improved clinical outcomes are lacking. Furthermore, experts remain concerned about the lack of regulation of herbs/supplements and the need for further research on potential adverse effects and herb–drug interactions. In conclusion, preliminary data on several herbs have demonstrated promising antioxidant, anti-inflammatory, anti-apoptotic, and anti-adipogenic properties that may help curtail the progression of NAFLD/NASH. Clinical trials testing the safety and efficacy must be completed before widespread use can be recommended.

Effects of Stigmasterol and β-Sitosterol on Nonalcoholic Fatty Liver Disease in a Mouse Model: A Lipidomic Analysis

To study the effects of stigmasterol and β-sitosterol on high-fat Western diet (HFWD)-induced nonalcoholic fatty liver disease (NAFLD), lipidomic analyses were conducted in liver samples collected after 33 weeks of the treatment. Principal component analysis showed these phytosterols were effective in protecting against HFWD-induced NAFLD. Orthogonal projections to latent structures-discriminate analysis (OPLS-DA) and S-plots showed that triacylglycerols (TGs), phosphatidylcholines, cholesteryl esters, diacylglycerols, and free fatty acids (FFAs) were the major lipid species contributing to these discriminations. The alleviation of NAFLD is mainly associated with decreases in hepatic cholesterol, TGs with polyunsaturated fatty acids, and alterations of free hepatic FFA. In conclusion, phytosterols, at a dose comparable to that suggested for humans by the FDA for the reduction of plasma cholesterol levels, are shown to protect against NAFLD in this long-term (33-week) study.

Phytochemicals That Influence Gut Microbiota as Prophylactics and for the Treatment of Obesity and Inflammatory Diseases

Gut microbiota (GM) plays several crucial roles in host physiology and influences several relevant functions. In more than one respect, it can be said that you “feed your microbiota and are fed by it.” GM diversity is affected by diet and influences metabolic and immune functions of the host's physiology. Consequently, an imbalance of GM, or dysbiosis, may be the cause or at least may lead to the progression of various pathologies such as infectious diseases, gastrointestinal cancers, inflammatory bowel disease, and even obesity and diabetes. Therefore, GM is an appropriate target for nutritional interventions to improve health. For this reason, phytochemicals that can influence GM have recently been studied as adjuvants for the treatment of obesity and inflammatory diseases. Phytochemicals include prebiotics and probiotics, as well as several chemical compounds such as polyphenols and derivatives, carotenoids, and thiosulfates. The largest group of these comprises polyphenols, which can be subclassified into four main groups: flavonoids (including eight subgroups), phenolic acids (such as curcumin), stilbenoids (such as resveratrol), and lignans. Consequently, in this review, we will present, organize, and discuss the most recent evidence indicating a relationship between the effects of different phytochemicals on GM that affect obesity and/or inflammation, focusing on the effect of approximately 40 different phytochemical compounds that have been chemically identified and that constitute some natural reservoir, such as potential prophylactics, as candidates for the treatment of obesity and inflammatory diseases.

Inhibitory effect of thiacremonone on MPTP-induced dopaminergic neurodegeneration through inhibition of p38 activation

Neuroinflammation is implicated for dopaminergic neurodegeneration. Sulfur compounds extracted from garlic have been shown to have anti-inflammatory properties. Previously, we have investigated that thiacremonone, a sulfur compound isolated from garlic has anti-inflammatory effects on several inflammatory disease models. To investigate the protective effect of thiacremonone against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced behavioral impairment and dopaminergic neurodegeneration, 8 week old ICR mice were given thiacremonone (10 mg/kg) in drinking water for 1 month and received intraperitoneal injection of MPTP (15 mg/kg, four times with 2 h interval) during the last 7 days of treatment. Our data showed that thiacremonone decreased MPTP-induced behavioral impairments (Rotarod test, Pole test, and Gait test), dopamine depletion and microglia and astrocytes activations as well as neuroinflammation. Higher activation of p38 was found in the substantia nigra and striatum after MPTP injection, but p38 activation was reduced in thiacremonone treated group. In an in vitro study, thiacremonone (1, 2, and 5 μg/ml) effectively decreased MPP+ (0.5 mM)-induced glial activation, inflammatory mediators generation and dopaminergic neurodegeneration in cultured astrocytes and microglial BV-2 cells. Moreover, treatment of p38 MAPK inhibitor SB203580 (10 μM) further inhibited thiacremonone induced reduction of neurodegeneration and neuroinflammation. These results indicated that the anti-inflammatory compound, thiacremonone, inhibited neuroinflammation and dopaminergic neurodegeneration through inhibition of p38 activation.

Diallyl disulphide inhibits apolipoprotein(a) expression in HepG2 cells through the MEK1-ERK1/2-ELK-1 pathway

Background

Lipoprotein(a) [LP(a)] is implicated as a common and independent risk factor for cardiovascular diseases. The therapeutic options currently available for reducing plasma LP(a) concentrations are limited. Diallyl disulphide (DADS), the main component of garlic, regulates lipid metabolism in hepatocytes and adipocytes through ERK1/2 signalling. This study aimed to assess the effect of DADS on apolipoprotein(a) [apo(a)] in HepG2 cells. We also determined the effects of DADS on apo(a) expression and secretion in HepG2 cells as well as the underlying mechanisms.

Methods

We examined the role of DADS on apo(a) expression in HepG2 cells by treating cell with different concentrations of DADS (10, 20, 40 and 80 μg/mL) for 24 h or treating cells with 40 μg/mL DADS for 0, 6, 12, 24 and 48 h. Then we used quantitative real-time PCR to analysis apo(a) mRNA levels, used Western blot to analysis apo(a) protein levels and used enzyme-linked immunosorbent assay to test apo(a) secreted levels. To farther determined the role of DADS, we applied Transfection of small interfering RNA to knockdown ELK-1levels and applied PD98059, a specific inhibitor of ERK1/2, to block ERK1/2 signal.

Results

The results show DADS inhibited apo(a) at both the mRNA and protein levels in HepG2 cells in a dose-dependent manner. DADS-mediated inhibition of apoa(a) expression in HepG2 cells was attenuated when the cells were cultured in medium containing PD98059 (ERK1/2 inhibitor) or were transfected with siRNAs against MEK1 or ELK-1. Overexpression of apo(a) yielded similar results.

Conclusions

This study reveals that DADS can downregulate apo(a) expression in a dose-dependent manner via the MEK-ERK12-ELK-1 pathway.

Beneficial effects of paeoniflorin on non-alcoholic fatty liver disease induced by high-fat diet in rats

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver diseases. This study sought to evaluate the insulin-sensitizing effect of paeoniflorin (PF) on high-fat diet-induced NAFLD and possible molecular mechanisms. Male Sprague Dawley rats were fed a high-fat diet (HFD) for 10 weeks to establish the NAFLD model, and PF (20 mg/kg/d) was gavaged to the NAFLD rats for another four weeks. Our results demonstrated that HFD resulted in hepatocellular ballooning, micro-/macrovesicular steatosis, and oxidative stress in the liver, accompanied by increased serum total cholesterol (TC), triglyceride (TG), free fatty acid (FFA), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels and homeostasis model of insulin resistance (HOMA-IR) index. PF treatment improved the biochemical and histopathological changes in NAFLD rats. Moreover, we also found that PF could inhibit lipid ectopic deposition via regulating lipid metabolism (inhibiting lipid synthesis of cholesterol and de novo pathway), and exert insulin sensitizing effect by regulating the insulin signaling pathway IRS/Akt/GSK3β and anti-oxidation. The study findings suggest that PF has therapeutic potential against NAFLD and that it acts through multiple signaling pathways.

Therapeutic Role of Functional Components in Alliums for Preventive Chronic Disease in Human Being

Objectives. Functional components in alliums have long been maintained to play a key role in modifying the major risk factors for chronic disease. To obtain a better understanding of alliums for chronic disease prevention, we conducted a systematic review for risk factors and prevention strategies for chronic disease of functional components in alliums, based on a comprehensive English literature search that was conducted using various electronic search databases, especially the PubMed, ISI Web of Science, and CNKI for the period 2007-2016. Allium genus especially garlic, onion, and Chinese chive is rich in organosulfur compounds, quercetin, flavonoids, saponins, and others, which have anticancer, preventive cardiovascular and heart diseases, anti-inflammation, antiobesity, antidiabetes, antioxidants, antimicrobial activity, neuroprotective and immunological effects, and so on. These results support Allium genus; garlic and onion especially may be the promising dietotherapeutic vegetables and organopolysulfides as well as quercetin mechanism in the treatment of chronic diseases. This review may be used as scientific basis for the development of functional food, nutraceuticals, and alternative drugs to improve the chronic diseases.

Diet Supplementation with Allicin Protects against Alcoholic Fatty Liver Disease in Mice by Improving Anti-inflammation and Antioxidative Functions

This study investigated the liver-protective effects of allicin, an active compound in fresh garlic, against alcoholic fatty liver disease (AFLD) and liver inflammation. Its effects were investigated in an AFLD model in male C57BL/6 mice, which were fed Lieber-DeCarli liquid diet containing ethanol. Allicin (5 and 20 mg/kg bw/day) was orally administered daily in the AFLD mice for 4 weeks. The results indicate that allicin promotes hepatoprotection by significantly reducing aspartate transaminase (AST) and alanine transaminase (ALT) levels (p < 0.05) in the plasma, which are key indicators of liver damage. Allicin reduced fat accumulation, increased glutathione and catalase levels, and decreased microsomal protein cytochrome P450 2E1 (CYP2E1) expression (p < 0.05) in the livers of the AFLD mice. Furthermore, allicin supplementation significantly decreased the levels of proinflammatory tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 and suppressed the expression of sterol regulatory element-binding protein-1 (SREBP-1) (p < 0.05). Additionally, it improved the hepatic alcohol dehydrogenase (ADH) activity (p < 0.05). Collectively, these findings demonstrate that allicin attenuates liver oxidative stress and inflammation.

Anti-depressant effects of Gastrodia elata Blume and its compounds gastrodin and 4-hydroxybenzyl alcohol, via the monoaminergic system and neuronal cytoskeletal remodeling

ETHNOPHARMACOLOGY RELEVANCE

Gastrodia elata Blume is a highly valuable traditional Chinese medicine used in the treatment of depression. However, compounds with antidepressant effects in water extracts of G. elata Bl. (WGE) have not been identified. The aims of this study were to determine the major antidepressant compound in WGE and to evaluate the antidepressant effects of WGE and its active compounds which involved the monoaminergic system and neuronal cytoskeletal remodeling.

MATERIALS AND METHODS

Gastrodin (GAS) and 4-hydroxybenzyl alcohol (HBA) in WGE, were analyzed with high-performance liquid chromatography (HPLC)-ultraviolet detection. The forced swimming test (FST) was used to induce depression-like symptoms in 9 weeks old male Sprague-Dawley rats. The open field test (OFT) was used to measure anxiety after WGE, GAS, and HBA treatments. The levels of monoamine such as serotonin (5-HT), dopamine (DA), and their metabolites 5-hydroxyindoleacetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) were measured using HPLC-electrochemical detection. Western blotting was used to examine the 5-HT1A receptor and the neuronal cytoskeleton remodeling-related proteins, Slit, dihydropyrimidinase-related protein 2 (DPYSL2, also called CRMP2), Ras homologous member A (RhoA), and profilin 1 (PFN1) in vivo. Slit1 expression was evaluated in Hs683 cell line after treated with WGE (0.5mg/mL), GAS (50, 100 and 100μM), and HBA (50, 100 and 100μM).

RESULTS

Oral administration of WGE (500mg/kg bw), GAS (100mg/kg bw), and HBA (100mg/kg bw) exhibited the anti-depressant effect by significantly reducing the immobility time in FST, monoamine metabolism including the 5-HT to 5-HIAA in the hippocampus and DA to DOPAC and HVA ratios in the frontal cortex, amygdala, and hippocampus. In the hippocampus, the expression of the neuronal cytoskeleton remodeling-related negative regulators Slit1 and RhoA were significantly down-regulated. In addition, the positive regulators CRMP2 and PFN1 were significantly up-regulated following GAS, HBA, and WGE treatments. Moreover, WGE, GAS, and HBA were directly down-regulated Slit1 expression in Hs683 cells.

CONCLUSION

WGE, GAS, and HBA exhibited potential anti-depressant effects in rats by decreasing monoamine metabolism and modulated cytoskeleton remodeling-related protein expression in the Slit-Robo pathway. These results suggest that WGE can be used as agent for depressive prevention.

Anti-adipocyte Differentiation Activity and Chemical Composition of Essential Oil from Artemisia annua

Artemisia annua L. essential oil (AAEO) has diverse properties including antibacterial, antioxidant, antinociceptive, and antimicrobial activities. However, the effect of AAEO on obesity remains to be investigated. In this study, we analyzed the compounds of AAEO and explored the effect of AAEO on the differentiation of preadipocyte into adipocyte using preadipocyte cell line 3T3-L1. Total yield of AAEO from 20 kg A. annua leaf and flower was 0.5%, v/w. Gas chromatography-mass spectrometry analysis showed that AAEO contained 34 compounds. 3T3-L1 cells incubated in 3-isobutyl-1-methylxanthine / dexamethasone / insulin (MDI)-containing medium showed increased accumulation of lipid droplets. This increased response was suppressed by treatment with AAEO. Expressions of obesity-related proteins (PPARγ, C/EBPα, SREBP-1c, FAS, and ACC) were increased in 3T3-L1 cells cultured in MDI medium and these responses were decreased by treatment with AAEO. These findings demonstrate that AAEO may suppress 3T3-L1 cell differentiation by inhibiting adipogenesis and activation of lipid metabolism-related proteins.

Chokeberry attenuates the expression of genes related to de novo lipogenesis in the hepatocytes of mice with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), which is characterized by steatosis, is a major public health concern. Previous studies have shown that chokeberry has anti-inflammatory, antimutagenic, hepatoprotective, cardioprotective, and antidiabetic effects. In this study, we hypothesized that chokeberry powder can attenuate the expression of genes related to de novo lipogenesis and the triglyceride levels in the hepatocytes of mice with high-fat diet-induced NAFLD. After coadministering chokeberry powder for 8weeks (0.5% and 1% powder) with a high-fat diet, mice that consumed chokeberry powder diets, regardless of the dose, had significantly lower liver triglyceride levels than control mice that were fed a high-fat diet (P=.0145 and P<.0012, respectively). Compared with mice that were fed a high-fat diet, mice that were given 1% chokeberry powder exhibited significantly decreased mRNA expression of sterol regulatory element-binding protein (P=.009) and acetyl-CoA carboxylase (P=.0032) in the liver. Compared with mice in the control group, fatty acid synthase (FAS) expression significantly increased in the mice that were fed a high-fat diet, but both chokeberry powder-treated groups had significantly decreased FAS expression (P=.0157 and P<.0001, respectively). The size of the fat droplets was decreased in the livers of the chokeberry-supplemented groups. In summary, the administration of chokeberry powder may help attenuate high-fat diet-induced NAFLD by regulating the expression levels of sterol regulatory element-binding protein, acetyl-CoA carboxylase, and FAS and by decreasing the size of the fat droplets in the liver.

α-Mangostin Regulates Hepatic Steatosis and Obesity through SirT1-AMPK and PPARγ Pathways in High-Fat Diet-Induced Obese Mice

Previous studies have shown that α-mangostin (α-MG) suppresses intracellular fat accumulation and stimulation of lipolysis in in vitro systems. Together with the relatively high distribution of α-MG in liver and fat, these observations made it possible to propose a plausible hypothesis that an α-MG supplement may regulate hepatic steatosis and obesity. An α-MG supplement (50 mg/kg) reduced the body weight gain (13.8%) and epidymal and retroperitoneal fat mass accumulation (15.0 and 11.3%, respectively), as well as the biochemical serum profiles such as cholesterol [TC (26.9%), LDL-C (39.1%), and HDL-C (15.3%)], glucose (30.2%), triglyceride (29.7%), and fatty acid (30.3%) levels in high-fat fed mice compared with the high-fat diet-treated group, indicating that α-MG may regulate lipid metabolism. In addition, an α-MG supplement up-regulated hepatic AMPK, SirT1, and PPARγ levels compared with the high-fat diet states, suggesting that α-MG regulates hepatic steatosis and obesity through the SirT1-AMPK and PPARγ pathways in high-fat diet-induced obese mice.

Mass-Spectrometry-Based Serum Metabolomics of a C57BL/6J Mouse Model of High-Fat-Diet-Induced Non-alcoholic Fatty Liver Disease Development

Obesity, dyslipidemia, insulin resistance, oxidative stress, and inflammation are key clinical risk factors for the progression of non-alcoholic fatty liver disease (NAFLD). Currently, there is no comprehensive metabolic profile of a well-established animal model that effectively mimics the etiology and pathogenesis of NAFLD in humans. Here, we report the pathophysiological and metabolomic changes associated with NAFLD development in a C57BL/6J mouse model in which NAFLD was induced by feeding a high-fat diet (HFD) for 4, 8, 12, and 16 weeks. Serum metabolomic analysis was conducted using ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) and gas chromatography-mass spectrometry (GC-MS) to establish a metabolomic profile. Analysis of the metabolomic profile in combination with principal component analysis revealed marked differences in metabolites between the control and HFD group depending upon NAFLD severity. A total of 30 potential biomarkers were strongly associated with the development of NAFLD. Among these, 11 metabolites were mainly related to carbohydrate metabolism, hepatic biotransformation, collagen synthesis, and gut microbial metabolism, which are characteristics of obesity, as well as significantly increased serum glucose, total cholesterol, and hepatic triglyceride levels during the onset of NAFLD (4 weeks). At 8 weeks, 5 additional metabolites that are chiefly involved in perturbation of lipid metabolism and insulin secretion were found to be associated with hyperinsulinemia, hyperlipidemia, and hepatic steatosis in the mid-term of NAFLD progression. At the end of 12 and 16 weeks, 14 additional metabolites were predominantly correlated to abnormal bile acid synthesis, oxidative stress, and inflammation, representing hepatic inflammatory infiltration during NAFLD development. These results provide potential biomarkers for early risk assessment of NAFLD and further insights into NAFLD development.

Supplementation of chitosan alleviates high-fat diet-enhanced lipogenesis in rats via adenosine monophosphate (AMP)-activated protein kinase activation and inhibition of lipogenesis-associated genes

This study investigated the role of chitosan in lipogenesis in high-fat diet-induced obese rats. The lipogenesis-associated genes and their upstream regulatory proteins were explored. Diet supplementation of chitosan efficiently decreased the increased weights in body, livers, and adipose tissues in high-fat diet-fed rats. Chitosan supplementation significantly raised the lipolysis rate; attenuated the adipocyte hypertrophy, triglyceride accumulation, and lipoprotein lipase activity in epididymal adipose tissues; and decreased hepatic enzyme activities of lipid biosynthesis. Chitosan supplementation significantly activated adenosine monophosphate (AMP)-activated protein kinase (AMPK) phosphorylation and attenuated high-fat diet-induced protein expressions of lipogenic transcription factors (PPAR-γ and SREBP1c) in livers and adipose tissues. Moreover, chitosan supplementation significantly inhibited the expressions of downstream lipogenic genes (FAS, HMGCR, FATP1, and FABP4) in livers and adipose tissues of high-fat diet-fed rats. These results demonstrate for the first time that chitosan supplementation alleviates high-fat diet-enhanced lipogenesis in rats via AMPK activation and lipogenesis-associated gene inhibition.

Recent advances in dietary supplementation, in treating non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is currently known as the most common liver problem, characterized by excessive lipid accumulation in hepatocytes, which may progress to other liver diseases such as nonalcoholic steatohepatitis, hepatic tissue fibrosis, liver cirrhosis, and failure or hepatocellular carcinoma. Since NAFLD is positively associated with the development of obesity, insulin resistance, and ultimately type 2 diabetes mellitus, it is often regarded as the hepatic manifestation of the metabolic syndrome. No pharmacologic treatment has yet been proven for this disease. For most patients with presumed or confirmed NAFLD, the only proven strategy is to offer lifestyle advice that can lead to sustained weight loss. Since insulin resistance, oxidative stress, inflammation, and necro-apoptosis are involved in NAFLD pathogenesis, it seems that every potential therapeutic agent should target one or some of these pathologic events. There are many well known anti-oxidants, anti-inflammatory, and insulin sensitizer dietary supplements which have shown beneficial effects on NAFLD improvement in animal and human studies. The purpose of this review is to explore the existing evidences on dietary supplements considered to have hepatoprotective properties, and to present some proposed mechanisms by which they may protect against NAFLD.

The effects of black garlic (Allium satvium) extracts on lipid metabolism in rats fed a high fat diet

BACKGROUD/OBEJECTIVES

The mechanism of how black garlic effects lipid metabolism remains unsolved. Therefore, the objectives of this study were to determine the effects of black garlic on lipid profiles and the expression of related genes in rats fed a high fat diet.

MATERIALS/METHODS

Thirty-two male Sqrague-Dawley rats aged 4 weeks were randomly divided into four groups (n=8) and fed the following diets for 5 weeks: normal food diet, (NF); a high-fat diet (HF); and a high-fat diet + 0.5% or 1.5% black garlic extract (HFBG0.5 or HFBG1.5). Body weights and blood biochemical parameters, including lipid profiles, and expressions of genes related to lipid metabolism were determined.

RESULTS

Significant differences were observed in the final weights between the HFBG1.5 and HF groups. All blood biochemical parameters measured in the HFBG1.5 group showed significantly lower values than those in the HF group. Significant improvements of the plasama lipid profiles as well as fecal excretions of total lipids and triglyceride (TG) were also observed in the HFBG1.5 group, when compared to the HF diet group. There were significant differences in the levels of mRNA of sterol regulatory element binding protein-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G6PDH) in the HFBG1.5 group compared to the HF group. In addition, the hepatic expression of (HMG-CoA) reductase and Acyl-CoA cholesterol acyltransferase (ACAT) mRNA was also significantly lower than the HF group.

CONCLUSIONS

Consumption of black garlic extract lowers SREBP-1C mRNA expression, which causes downregulation of lipid and cholestrol metahbolism. As a result, the blood levels of total lipids, TG, and cholesterol were decreased.