Silybum marianum oil attenuates hepatic steatosis and oxidative stress in high fat diet-fed mice

Evaluating the therapeutic effect of different forms of silymarin on liver status and expression of some genes involved in fat metabolism, antioxidants and anti-inflammatory in older laying hens

BACKGROUND

Silymarin, the predominant compound of milk thistle, is an extract took out from milk thistle (Silybum marianum) seeds, containing a mixture of flavonolignans with strong antioxidant capability.

METHODS

The experiment was conducted using 70 Lohmann LSL-Lite hens at 80 weeks of age with 7 treatments each with 10 replicates. Treatments included: (1) control diet without silymarin, (2) daily intake of 100 mg silymarin powder/kg body weight (BW) (PSM100), (3) daily intake of 200 mg silymarin powder/kg BW (PSM200), (4) daily intake of 100 mg nano-silymarin/kg BW (NSM100), (5) daily intake of 200 mg nano-silymarin/kg BW (NSM200), (6) daily intake of 100 mg lecithinized silymarin/kg BW (LSM100) and (7) daily intake of 200 mg lecithinized silymarin/kg BW (LSM200). The birds were housed individually, and diets were fed for 12 weeks.

RESULTS

Scanning electron microscopy showed that NSM was produced with the average particle size of 20.30 nm. Silymarin treatment improved serum antioxidant enzyme activity. All groups receiving silymarin showed a decrease in liver malondialdehyde content, expression of fatty acid synthase, tumour necrosis factor alpha, interleukin 6 (IL-6) genes in the liver, and hepatic steatosis than the control, except those fed the PSM100 diet. There were decreases in liver dry matter and fat contents, non-alcoholic fatty liver disease and hepatocyte ballooning, and an increase in glutathione peroxidase gene expression and a decrease in iNOS gene expression in birds fed the NSM100, NSM200, LSM100 and LSM200 diets compared to the control group. Moreover, all groups receiving silymarin showed a significant decrease in liver weight compare to the control group.

CONCLUSIONS

Overall, the effects of silymarin when converted to NSM or LSM and offered at the level of 200 mg/kg BW were more pronounced on the hepatic variables and may be useful in the prevention of the liver disease in older laying hens.

Hepatocellular Interactions of Potential Nutraceuticals in the Management of Inflammatory NAFLD

Numerous studies highlight the potential of natural antioxidants, such as those found in foods and plants, to prevent or treat nonalcoholic fatty liver disease (NAFLD). Inflammation is a key factor in the progression from high-fat diet-induced NAFLD to nonalcoholic steatohepatitis (NASH). Injured liver cells and immune cells release inflammatory cytokines, activating hepatic stellate cells. These cells acquire a profibrogenic phenotype, leading to extracellular matrix accumulation and fibrosis. Persistent fibrosis can progress to cirrhosis. Fatty infiltration, oxidative stress, and inflammation exacerbate fatty liver diseases. Thus, many plant-derived antioxidants, like silymarin, silibinin, curcumin, resveratrol, berberine, and quercetin, have been extensively studied in experimental models and clinical patients with NAFLD. Experimentally, these compounds have shown beneficial effects in reducing lipid accumulation, oxidative stress, and inflammatory markers by modulating the ERK, NF-κB, AMPKα, and PPARγ pathways. They also help decrease metabolic endotoxemia, intestinal permeability, and gut inflammation. Clinically, silymarin and silibinin have been found to reduce transaminase levels, while resveratrol and curcumin help alleviate inflammation in NAFLD patients. However, these phytocompounds exhibit poor water solubility, leading to low oral bioavailability and hindering their biological efficacy. Additionally, inconclusive clinical results highlight the need for further trials with larger populations, longer durations, and standardized protocols.

Silymarin inhibits the lipogenic pathway and reduces worsening of non-alcoholic fatty liver disease (NAFLD) in mice

CONTEXT

The role of silymarin in hepatic lipid dysfunction and its possible mechanisms of action were investigated.

OBJECTIVE

To evaluate the effects of silymarin on hepatic and metabolic profiles in mice fed with 30% fructose for 8 weeks.

METHODS

We evaluated the antioxidant profile of silymarin; mice consumed 30% fructose and were treated with silymarin (120 mg/kg/day or 240 mg/kg/day). We performed biochemical, redox status, and histopathological assays. RT-qPCR was performed to detect ACC-1, ACC-2, FAS, and CS expression, and western blotting to detect PGC-1α levels.

RESULTS

Silymarin contains high levels of phenolic compounds and flavonoids and exhibited significant antioxidant capacity in vitro. In vivo, the fructose-fed groups showed increased levels of AST, ALT, SOD/CAT, TBARS, hepatic TG, and cholesterol, as well as hypertriglyceridaemia, hypercholesterolaemia, and increased ACC-1 and FAS. Silymarin treatment reduced these parameters and increased mRNA levels and activity of hepatic citrate synthase.

CONCLUSIONS

These results suggest that silymarin reduces worsening of NAFLD.

The Role of Antioxidants in the Treatment of Metabolic Dysfunction-Associated Fatty Liver Disease: A Systematic Review

Non-alcoholic fatty liver disease (NAFLD) is a global public health problem that causes liver-related morbidity and mortality. It is also an independent risk factor for non-communicable diseases. In 2020, a proposal was made to refer to it as "metabolic dysfunction-associated fatty liver disease (MAFLD)", with concise diagnostic criteria. Given its widespread occurrence, its treatment is crucial. Increased levels of oxidative stress cause this disease. This review aims to evaluate various studies on antioxidant therapies for patients with MAFLD. A comprehensive search for relevant research was conducted on the PubMed, SCOPUS, and ScienceDirect databases, resulting in the identification of 87 studies that met the inclusion criteria. In total, 31.1% of human studies used natural antioxidants, 53.3% used synthetic antioxidants, and 15.5% used both natural and synthetic antioxidants. In human-based studies, natural antioxidants showed 100% efficacy in the treatment of MAFLD, while synthetic antioxidants showed effective results in only 91% of the investigations. In animal-based research, natural antioxidants were fully effective in the treatment of MAFLD, while synthetic antioxidants demonstrated effectiveness in only 87.8% of the evaluations. In conclusion, antioxidants in their natural form are more helpful for patients with MAFLD, and preserving the correct balance of pro-oxidants and antioxidants is a useful way to monitor antioxidant treatment.

Milk thistle protects against non-alcoholic fatty liver disease induced by dietary thermally oxidized tallow

Non-alcoholic fatty liver disease (NAFLD) is a chronic condition caused by several factors including thermally oxidized tallow. Various strategies have been considered to ameliorate NAFLD. However, the role of milk thistle (MT) in ameliorating NAFLD caused by thermally oxidized tallow has not been reported. The purpose of this study was to evaluate the ability of milk thistle to protect rabbits from the toxicity of oxidized tallow (OT). The rabbits were given OT and an extract of MT. The composition of MT was analyzed using HPLC-DAD, and tallow samples were studied using GC-MS. The study also examined liver histology, antioxidant levels, liver-related inflammatory markers, and serum lipid profile. The results showed that the major components of the MT extract were silybin B, formononetin-glucuronic acid, proanthocyanidin B1, silychristin B, silydianin, and isosilybin A. The group given OT showed elevated lipid profiles, lower antioxidant status, higher levels of hepatic inflammatory markers, and lower levels of anti-inflammatory markers. This group also had higher fat storage in the liver compared to the control or treatment groups. However, when MT was supplemented, the pro-inflammatory cytokines (IL-1, IL-4, IL-6, and TNF-α) and antioxidant status (CAT, SOD, GSH-Px, GSH, and TBARS) of the liver returned to normal. This suggests that MT extract is an excellent source of hepatoprotective compounds. It protects the liver by increasing antioxidant enzymes, decreasing pro-inflammatory cytokines, and increasing anti-inflammatory markers.

Genistein and sex hormone treatment alleviated hepatic fat accumulation and inflammation in orchidectomized rats with nonalcoholic steatohepatitis

Testosterone deficiency has been reported to accelerate nonalcoholic fatty liver disease (NAFLD). However, there are minimal data on the risk of NAFLD in transgender women and the treatment of NAFLD in this population. This study aimed to investigate the treatment effects and the mechanisms of action of genistein and sex hormones in orchiectomized (ORX) rats with nonalcoholic steatohepatitis (NASH) induced by a high fat high fructose diet (HFHF). Seven-week old male Sprague-Dawley rats were randomly divided into 7 groups (n = 6 each group); 1) control group, 2) ORX + standard diet group, 3) HFHF group, 4) ORX + HFHF group, 5) ORX + HFHF diet + testosterone group (50 mg/kg body weight (BW) once weekly), 6) ORX + HFHF diet + estradiol group (1.6 mg/kg BW daily), and 7) ORX + HFHF diet + genistein group (16 mg/kg BW daily). The duration of treatment was 6 weeks. Liver tissue was used for histological examination by hematoxylin and eosin staining and hepatic fat measurement by Oil Red O staining. Protein expression levels of histone deacetylase3 (HDAC3) and peroxisome proliferator-activated receptor delta (PPARδ) were analyzed by immunoblotting. Hepatic nuclear factor (NF)-ĸB expression was evaluated by immunohistochemistry. Rats in the ORX + HFHF group had the highest degree of hepatic steatosis, lobular inflammation, hepatocyte ballooning and the highest percentage of positive Oil Red O staining area among all groups. The expression of HDAC3 and PPARδ was downregulated, while NF-ĸB expression was upregulated in the ORX + HFHF group when compared with control and ORX + standard diet groups. Testosterone, estradiol and genistein treatment improved histological features of NASH together with the reversal of HDAC3, PPARδ and NF-ĸB protein expression comparing with the ORX + HFHF group. In summary, genistein and sex hormone treatment could alleviate NASH through the up-regulation of HDAC3 and PPARδ, and the suppression of NF-ĸB expression.

The promising roles of medicinal plants and bioactive compounds on hepatic lipid metabolism in the treatment of non-alcoholic fatty liver disease in animal models: molecular targets

Imbalance in hepatic lipid metabolism can lead to an abnormal triglycerides deposition in the hepatocytes which can cause non-alcoholic fatty liver disease (NAFLD). Four main mechanisms responsible for regulating hepatic lipid metabolism are fatty acid uptake, de novo lipogenesis, lipolysis and fatty acid oxidation. Controlling the expression of transcription factors at molecular level plays a crucial role in NAFLD management. This paper reviews various medicinal plants and their bioactive compounds emphasising mechanisms involved in hepatic lipid metabolism, other important NAFLD pathological features, and their promising roles in managing NAFLD through regulating key transcription factors. Although there are many medicinal plants popularly investigated for NAFLD treatment, there is still little information and scientific evidence available and there has been no research on clinical trials scrutinised on this matter. This review also aims to provide molecular information of medicinal plants in NALFD treatment that might have potentials for future scientifically controlled studies.

Assessment of Quality and Efficiency of Cold-Pressed Oil from Selected Oilseeds

In this present study, an oil press was used to process 200 g each of sesame, pumpkin, flax, milk thistle, hemp and cumin oilseeds in order to evaluate the amount of oil yield, seedcake, sediments and material losses (oil and sediments). Sesame produced the highest oil yield at 30.60 ± 1.69%, followed by flax (27.73 ± 0.52%), hemp (20.31 ± 0.11%), milk thistle (14.46 ± 0.51%) and pumpkin (13.37 ± 0.35%). Cumin seeds produced the lowest oil yield at 3.46 ± 0.15%. The percentage of sediments in the oil, seedcake and material losses for sesame were 5.15 ± 0.09%, 60.99 ± 0.04% and 3.27 ± 1.56%. Sediments in the oil decreased over longer storage periods, thereby increasing the percentage oil yield. Pumpkin oil had the highest peroxide value at 18.45 ± 0.53 meq O2/kg oil, an acid value of 11.21 ± 0.24 mg KOH/g oil, free fatty acid content of 5.60 ± 0.12 mg KOH/g oil and iodine value of 14.49 ± 0.16 g l/100 g. The univariate ANOVA of the quality parameters against the oilseed type was statistically significant (p-value < 0.05), except for the iodine value, which was not statistically significant (p-value > 0.05). Future studies should analyze the temperature generation, oil recovery efficiency, percentage of residual oil in the seedcake and specific energy consumption of different oilseeds processed using small-large scale presses.

LC-MS Metabolomic Profiling of Five Types of Unrefined, Cold-Pressed Seed Oils to Identify Markers to Determine Oil Authenticity and to Test for Oil Adulteration

The authenticity of food products marketed as health-promoting foods-especially unrefined, cold-pressed seed oils-should be controlled to ensure their quality and safeguard consumers and patients. Metabolomic profiling using liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (LC-QTOF) was employed to identify authenticity markers for five types of unrefined, cold-pressed seed oils: black seed oil (Nigella sativa L.), pumpkin seed oil (Cucurbita pepo L.), evening primrose oil (Oenothera biennis L.), hemp oil (Cannabis sativa L.) and milk thistle oil (Silybum marianum). Of the 36 oil-specific markers detected, 10 were established for black seed oil, 8 for evening primrose seed oil, 7 for hemp seed oil, 4 for milk thistle seed oil and 7 for pumpkin seed oil. In addition, the influence of matrix variability on the oil-specific metabolic markers was examined by studying binary oil mixtures containing varying volume percentages of each tested oil and each of three potential adulterants: sunflower, rapeseed and sesame oil. The presence of oil-specific markers was confirmed in 7 commercial oil mix products. The identified 36 oil-specific metabolic markers proved useful for confirming the authenticity of the five target seed oils. The ability to detect adulterations of these oils with sunflower, rapeseed and sesame oil was demonstrated.

Natural flavonoids exhibit potent anticancer activity by targeting microRNAs in cancer: A signature step hinting towards clinical perfection

Cancer prevalence and its rate of incidence are constantly rising since the past few decades. Owing to the toxicity of present-day antineoplastic drugs, it is imperative to explore safer and more effective molecules to combat and/or prevent this dreaded disease. Flavonoids, a class of polyphenols, have exhibited multifaceted implications against several diseases including cancer, without showing significant toxicity towards the normal cells. Shredded pieces of evidence suggest that flavonoids can enhance drug sensitivity and suppress proliferation, metastasis, and angiogenesis of cancer cells by modulating several oncogenic or oncosuppressor microRNAs (miRNAs, miRs). They play pivotal roles in regulation of various biological and pathological processes, including various cancers. In the present review, the structure, chemistry and miR targeting efficacy of quercetin, luteolin, silibinin, genistein, epigallocatechin gallate, and cyanidin against several cancer types are comprehensively discussed. miRs are considered as next-generation medicine of recent times, and their targeting by naturally occurring flavonoids in cancer cells could be deemed as a signature step. We anticipate that our compilations related to miRNA-mediated regulation of cancer cells by flavonoids might catapult the clinical investigations and affirmation in the future.

Mechanistic Insights into the Pharmacological Significance of Silymarin

Medicinal plants are considered the reservoir of diverse therapeutic agents and have been traditionally employed worldwide to heal various ailments for several decades. Silymarin is a plant-derived mixture of polyphenolic flavonoids originating from the fruits and akenes of Silybum marianum and contains three flavonolignans, silibinins (silybins), silychristin and silydianin, along with taxifolin. Silybins are the major constituents in silymarin with almost 70–80% abundance and are accountable for most of the observed therapeutic activity. Silymarin has also been acknowledged from the ancient period and is utilized in European and Asian systems of traditional medicine for treating various liver disorders. The contemporary literature reveals that silymarin is employed significantly as a neuroprotective, hepatoprotective, cardioprotective, antioxidant, anti-cancer, anti-diabetic, anti-viral, anti-hypertensive, immunomodulator, anti-inflammatory, photoprotective and detoxification agent by targeting various cellular and molecular pathways, including MAPK, mTOR, β-catenin and Akt, different receptors and growth factors, as well as inhibiting numerous enzymes and the gene expression of several apoptotic proteins and inflammatory cytokines. Therefore, the current review aims to recapitulate and update the existing knowledge regarding the pharmacological potential of silymarin as evidenced by vast cellular, animal, and clinical studies, with a particular emphasis on its mechanisms of action.

A Molecular Insight into the Role of Antioxidants in Nonalcoholic Fatty Liver Diseases

Nonalcoholic fatty liver disease (NAFLD) defines fat accumulation in the liver, and it is commonly associated with metabolic syndromes like diabetes and obesity. Progressive NAFLD leads to nonalcoholic steatohepatitis (NASH) and ultimately causes cirrhosis and hepatocellular carcinoma, and NASH is currently a frequent cause of liver transplantation. Oxidative stress is often contributed to the progression of NAFLD, and hence, antioxidants such as silymarin, silybin, or silibinin, pentoxifylline, resveratrol, and vitamins A, C, and E are used in clinical trials against NAFLD. Silymarin induces the peroxisome proliferator-activated receptor α (PPARα), a fatty acid sensor, which promotes the transcription of genes that are required for the enzymes involved in lipid oxidation in hepatocytes. Silybin inhibits sterol regulatory element-binding protein 1 and carbohydrate response element-binding protein to downregulate the expression of genes responsible for de novo lipogenesis by activating AMP-activated protein kinase phosphorylation. Pentoxifylline inhibits TNF-α expression and endoplasmic reticulum stress-mediated inflammatory nuclear factor kappa B (NF-κB) activation. Thus, it prevents NAFLD to NASH progression. Resveratrol inhibits methylation at Nrf-2 promoters and NF-κB activity via SIRT1 activation in NAFLD conditions. However, clinically, resveratrol has not shown promising beneficial effects. Vitamin C is beneficial in NAFLD patients. Vitamin E is not effectively regressing hepatic fibrosis. Hence, its combination with antifibrotic agents is used as an adjuvant to produce a synergistic antifibrotic effect. However, to date, none of these antioxidants have been used as a definite therapeutic agent in NAFLD patients. Further, these antioxidants should be studied in NAFLD patients with larger populations and multiple endpoints in the future.

Hepatoprotective mechanism of Silybum marianum on nonalcoholic fatty liver disease based on network pharmacology and experimental verification

The study aimed to identify the key active components in Silybum marianum (S. marianum) and determine how they protect against nonalcoholic fatty liver disease (NAFLD). TCMSP, DisGeNET, UniProt databases, and Venny 2.1 software were used to identify 11 primary active components, 92 candidate gene targets, and 30 core hepatoprotective gene targets in this investigation, respectively. The PPI network was built using a string database and Cytoscape 3.7.2. The KEGG pathway and GO biological process enrichment, biological annotation, as well as the identified hepatoprotective core gene targets were analyzed using the Metascape database. The effect of silymarin on NAFLD was determined using H&E on pathological alterations in liver tissues. The levels of liver function were assessed using biochemical tests. Western blot experiments were used to observe the proteins that were expressed in the associated signaling pathways on the hepatoprotective effect, which the previous network pharmacology predicted. According to the KEGG enrichment study, there are 35 hepatoprotective signaling pathways. GO enrichment analysis revealed that 61 biological processes related to the hepatoprotective effect of S. marianum were identified, which mainly involved in response to regulation of biological process and immune system process. Silymarin was the major ingredient derived from S. marianum, which exhibited the hepatoprotective effect by reducing the levels of ALT, AST, TC, TG, HDL-C, LDL-C, decreasing protein expressions of IL-6, MAPK1, Caspase 3, p53, VEGFA, increasing protein expression of AKT1. The present study provided new sights and a possible explanation for the molecular mechanisms of S. marianum against NAFLD.

Role of Silymarin in Cancer Treatment: Facts, Hypotheses, and Questions

The flavonoid silymarin extracted from the seeds of Sylibum marianum is a mixture of 6 flavolignan isomers. The 3 more important isomers are silybin (or silibinin), silydianin, and silychristin. Silybin is functionally the most active of these compounds. This group of flavonoids has been extensively studied and they have been used as hepato-protective substances for the mushroom Amanita phalloides intoxication and mainly chronic liver diseases such as alcoholic cirrhosis and nonalcoholic fatty liver. Hepatitis C progression is not, or slightly, modified by silymarin. Recently, it has also been proposed for SARS COVID-19 infection therapy. The biochemical and molecular mechanisms of action of these substances in cancer are subjects of ongoing research. Paradoxically, many of its identified actions such as antioxidant, promoter of ribosomal synthesis, and mitochondrial membrane stabilization, may seem protumoral at first sight, however, silymarin compounds have clear anticancer effects. Some of them are: decreasing migration through multiple targeting, decreasing hypoxia inducible factor-1α expression, inducing apoptosis in some malignant cells, and inhibiting promitotic signaling among others. Interestingly, the antitumoral activity of silymarin compounds is limited to malignant cells while the nonmalignant cells seem not to be affected. Furthermore, there is a long history of silymarin use in human diseases without toxicity after prolonged administration. The ample distribution and easy accessibility to milk thistle-the source of silymarin compounds, its over the counter availability, the fact that it is a weed, some controversial issues regarding bioavailability, and being a nutraceutical rather than a drug, has somehow led medical professionals to view its anticancer effects with skepticism. This is a fundamental reason why it never achieved bedside status in cancer treatment. However, in spite of all the antitumoral effects, silymarin actually has dual effects and in some cases such as pancreatic cancer it can promote stemness. This review deals with recent investigations to elucidate the molecular actions of this flavonoid in cancer, and to consider the possibility of repurposing it. Particular attention is dedicated to silymarin's dual role in cancer and to some controversies of its real effectiveness.

Protective Effects of Sesamol against Liver Oxidative Stress and Inflammation in High-Fat Diet-Induced Hepatic Steatosis

Chronic high-fat diet (HFD) is associated with the onset and progression of hepatic steatosis, and oxidative stress is highly involved in this process. The potential role of sesamol (SEM) against oxidative stress and inflammation at the transcriptional level in a mice model of hepatic steatosis is not known. In this study, we aimed to investigate the scavenging effects of SEM towards reactive oxygen generated by lipid accumulation in the liver of obese mice and to explore the mechanisms of protection. Markers of oxidative stress, vital enzymes involved in stimulating oxidative stress or inflammation, and nuclear transcription of Nrf2 were examined. Our results showed that SEM significantly inhibited the activity of the HFD-induced hepatic enzymes CYP2E1 and NOX2, associated with oxidative stress generation. Additionally, SEM reversed HFD-induced activation of NF-κB, a redox-sensitive transcription factor, and attenuated the expression of hepatic TNF-α, a proinflammatory molecule. Moreover, SEM enhanced HFD-induced hepatic Nrf2 nuclear transcription and increased the levels of its downstream target genes Ho1 and Nqo1, which indicated antiinflammation and antioxidant properties. Our study suggests that chronic HFD led to hepatic steatosis, while SEM exhibited protective effects on the liver by counteracting the oxidative stress and inflammation induced by HFD. The underlying mechanism might involve multiple pathways at the transcriptional level; the antioxidant defense mechanism was in partly mediated by the upregulation of Nrf2.

The Potential Application of Chinese Medicine in Liver Diseases: A New Opportunity

Liver diseases have been a common challenge for people all over the world, which threatens the quality of life and safety of hundreds of millions of patients. China is a major country with liver diseases. Metabolic associated fatty liver disease, hepatitis B virus and alcoholic liver disease are the three most common liver diseases in our country, and the number of patients with liver cancer is increasing. Therefore, finding effective drugs to treat liver disease has become an urgent task. Chinese medicine (CM) has the advantages of low cost, high safety, and various biological activities, which is an important factor for the prevention and treatment of liver diseases. This review systematically summarizes the potential of CM in the treatment of liver diseases, showing that CM can alleviate liver diseases by regulating lipid metabolism, bile acid metabolism, immune function, and gut microbiota, as well as exerting anti-liver injury, anti-oxidation, and anti-hepatitis virus effects. Among them, Keap1/Nrf2, TGF-β/SMADS, p38 MAPK, NF-κB/IκBα, NF-κB-NLRP3, PI3K/Akt, TLR4-MyD88-NF-κB and IL-6/STAT3 signaling pathways are mainly involved. In conclusion, CM is very likely to be a potential candidate for liver disease treatment based on modern phytochemistry, pharmacology, and genomeproteomics, which needs more clinical trials to further clarify its importance in the treatment of liver diseases.

Current innovations in nutraceuticals and functional foods for intervention of non-alcoholic fatty liver disease

As innovations in global agricultural production and food trading systems lead to major dietary shifts, high morbidity rates from non-alcoholic fatty liver disease (NAFLD), accompanied by elevated risk of lipid metabolism-related complications, has emerged as a growing problem worldwide. Treatment and prevention of NAFLD and chronic liver disease depends on the availability of safe, effective, and diverse therapeutic agents, the development of which is urgently needed. Supported by a growing body of evidence, considerable attention is now focused on interventional approaches that combines nutraceuticals and functional foods. In this review, we summarize the pathological progression of NAFLD and discuss the beneficial effects of nutraceuticals and the active ingredients in functional foods. We also describe the underlying mechanisms of these compounds in the intervention of NAFLD, including their effects on regulation of lipid homeostasis, activation of signaling pathways, and their role in gut microbial community dynamics and the gut-liver axis. In order to identify novel targets for treatment of lipid metabolism-related diseases, this work broadly explores the molecular mechanism linking nutraceuticals and functional foods, host physiology, and gut microbiota. Additionally, the limitations in existing knowledge and promising research areas for development of active interventions and treatments against NAFLD are discussed.

Milk thistle seed cold press oil attenuates markers of the metabolic syndrome in a mouse model of dietary-induced obesity

Milk thistle cold press oil (MTO) is an herbal remedy derived from Silybum marianum which contains a low level of silymarin and mixture of polyphenols and flavonoids. The effect of MTO on the cardiovascular and metabolic complications of obesity was studied in mice that were fed a high-fat diet (HFD) for 20 weeks and treated with MTO for the final 8 weeks of the diet. MTO treatment attenuated HFD-induced obesity, fasting hyperglycemia, hypertension, and induced markers of mitochondrial fusion and browning of white adipose. Markers of inflammation were also attenuated in both adipose and the liver of MTO-treated mice. In addition, MTO resulted in the improvement of liver fibrosis. These results demonstrate that MTO has beneficial actions to attenuate dietary obesity-induced weight gain, hyperglycemia, hypertension, inflammation, and suggest that MTO supplementation may prove beneficial to patients exhibiting symptoms of metabolic syndrome. PRACTICAL APPLICATIONS: Natural supplements are increasingly being considered as potential therapies for many chronic cardiovascular and metabolic diseases. Milk thistle cold press oil (MTO) is derived from Silybum marianum which is used as a dietary supplement in different parts of the world. The results of the present study demonstrate that MTO supplementation normalizes several metabolic and cardiovascular complications arising from dietary-induced obesity. MTO supplementation also had anti-inflammatory actions in the adipose as well as the liver. These results suggest that supplementation of MTO into the diet of obese individuals may afford protection against the worsening of cardiovascular and metabolic disease and improve inflammation and liver fibrosis.

Water Extract of Artemisia annua L. Exhibits Hepatoprotective Effects Through Improvement of Lipid Accumulation and Oxidative Stress-Induced Cytotoxicity

Nonalcoholic fatty liver disease (NAFLD) is a metabolic liver disease with a complex underlying mechanism that has not been completely understood. Thus, effective and safe drugs for this disease are not yet available. Artemisia annua L. is a medicinal plant with potent antimicrobial and antioxidant activities. In this study, we prepared a water extract of A. annua (WEAA) and examined its potential for NAFLD treatment. First, we pretreated HepG2 cells (human hepatocarcinoma cell line) with WEAA and then treated the cells with oleic acid or tert-butylhydroperoxide to examine the effect of WEAA on the lipid accumulation and the cytotoxicity, respectively. WEAA not only inhibited lipid accumulation within HepG2 cells but also protected cells from oxidative stress-mediated damage through the activation of antioxidant enzymes (such as activation of superoxide dismutase and production of glutathione) and its own scavenging activity. Next, to confirm protective effect of the WEAA in in vivo, mice were intragastrically administered with WEAA, extract of Silybum marianum or water once a day, and simultaneously provided with high-fat diet to induce fatty liver and hepatic steatosis. Oral administration of WEAA ameliorated weight gain and hepatic lipid accumulation in high-fat diet-fed mice. Moreover, the plasma levels of triglyceride, aspartate aminotransferase, and alanine aminotransferase were reduced in the WEAA-treated group. Our findings indicated that WEAA may be a potential intervention for preventing or treating hepatic lipid accumulation and liver damage.

Health Benefits of Silybum marianum: Phytochemistry, Pharmacology, and Applications

Silybum marianum (SM), a well-known plant used as both a medicine and a food, has been widely used to treat various diseases, especially hepatic diseases. The seeds and fruits of SM contain a flavonolignan complex called silymarin, the active compounds of which include silybin, isosilybin, silychristin, dihydrosilybin, silydianin, and so on. In this review, we thoroughly summarize high-quality publications related to the pharmacological effects and underlying mechanisms of SM. SM has antimicrobial, anticancer, hepatoprotective, cardiovascular-protective, neuroprotective, skin-protective, antidiabetic, and other effects. Importantly, SM also counteracts the toxicities of antibiotics, metals, and pesticides. The diverse pharmacological activities of SM provide scientific evidence supporting its use in both humans and animals. Multiple signaling pathways associated with oxidative stress and inflammation are the common molecular targets of SM. Moreover, the flavonolignans of SM are potential agonists of PPARγ and ABCA1, PTP1B inhibitors, and metal chelators. At the end of the review, the potential and perspectives of SM are discussed, and these insights are expected to facilitate the application of SM and the discovery and development of new drugs. We conclude that SM is an interesting dietary medicine for health enhancement and drug discovery and warrants further investigation.

Optimization of betacyanins from agricultural by-products using pressurized hot water extraction for antioxidant and in vitro oleic acid-induced steatohepatitis inhibitory activity

Pressurized hot water extraction (PHWE) is proposed to recover betacyanins from agricultural by-products (pitaya fruits peels (PFP), red beet stalks (RBS), and cactus pear peels (CPP)). The extraction yield of betacyanins was optimized by response surface methodology. The optimal PHWE conditions were attained and the actual yields of betacyanins under optimal conditions were well matched with the predicted yields. In addition, betacyanin pigment compositions as well as superoxide anion scavenging activity of individual betacyanins extract (BE) produced in optimal PHWE conditions were characterized by HPLC-ESI/MSⁿ and cyclic voltammetry. Furthermore, the inhibitory activity of three BEs on oleic acid-induced steatohepatitis in cellular model was comparatively investigated. The results showed that unlike PFP, RBS, and CPP presented excellent efficacy in decreasing intracellular triglyceride and reactive oxygen species, inhibiting the release of alanine aminotransferase and aspartate aminotransferase as well as regulating fatty acid synthase and carnitine palmitoyltransferase 1 mRNAs expression. Practical applications In this study, PHWE, is firstly proposed for the enhancement of the extraction of betacyanins from three agricultural by-products. Betacyanin-rich extracts by PHWE method exhibit excellent activities in inhibition of ROS and regulation of lipid metabolism in hepatic cells. It suggests that PHWE has a strong potentiality in keeping bioactivity of BEs, which is significant for the production of betacyanins functional foods.

Indole-3-Acetic Acid Alleviates Nonalcoholic Fatty Liver Disease in Mice via Attenuation of Hepatic Lipogenesis, and Oxidative and Inflammatory Stress

Recent evidences have linked indole-3-acetic acid (IAA), a gut microbiota-derived metabolite from dietary tryptophan, with the resistance to liver diseases. However, data supporting IAA-mediated protection against nonalcoholic fatty liver disease (NAFLD) from an in vivo study is lacking. In this study, we assessed the role of IAA in attenuating high-fat diet (HFD)-induced NAFLD in male C57BL/6 mice. Administration of IAA (50 mg/kg body weight) by intraperitoneal injection was found to alleviate HFD-induced elevation in fasting blood glucose and homeostasis model assessment of insulin resistance (HOMA-IR) index as well as plasma total cholesterol, low-density lipoprotein cholesterol (LDL-C), and glutamic-pyruvic transaminase (GPT) activity. Histological examination further presented the protective effect of IAA on liver damage induced by HFD feeding. HFD-induced an increase in liver total triglycerides and cholesterol, together with the upregulation of genes related to lipogenesis including sterol regulatory element binding-protein 1 (Srebf1), steraroyl coenzyme decarboxylase 1 (Scd1), peroxisome proliferator-activated receptor gamma (PPARγ), acetyl-CoA carboxylase 1 (Acaca), and glycerol-3-phosphate acyltransferase, mitochondrial (Gpam), which were mitigated by IAA treatment. The results of reactive oxygen species (ROS) and malonaldehyde (MDA) level along with superoxide dismutase (SOD) activity and glutathione (GSH) content in liver tissue evidenced the protection of IAA against HFD-induced oxidative stress. Additionally, IAA attenuated the inflammatory response of liver in mice exposed to HFD as shown by the reduction in the F4/80-positive macrophage infiltration and the expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α). In conclusion, our findings uncover that IAA alleviates HFD-induced hepatotoxicity in mice, which proves to be associated with the amelioration in insulin resistance, lipid metabolism, and oxidative and inflammatory stress.

Hepatoprotective effects of silymarin on CCl4-induced hepatic damage in broiler chickens model

This study was conducted to investigate the hepatoprotective effects of silymarin on CCl₄-induced oxidative stress in broiler chickens model. A total of 240 day-old broilers were divided into 4 equal groups (n = 60) composed of a control group (receiving 1 mL/Kg BW saline) and 3 groups treated with silymarin (receiving 100 mg/Kg BW silymarin), CCl₄ (receiving 1 mL/Kg BW CCl₄), and combination of silymarin + CCl₄. Results indicated that silymarin has potential to mitigate the deleterious effects of CCl₄ on protein and lipid metabolism. The protective activity of silymarin against CCl₄-mediated lipid peroxidation was demonstrated by the lower serum content of MDA, as lipid peroxidation marker. CCl₄-induced hepatotoxicity was demonstrated by the elevation of serum contents of ALP, AST, ALT, and GGT enzymes, whereas silymarin decreased serum activity of ALP and AST hepatic enzymes. The CCl₄-challenged birds revealed considerable hepatic injures characterized by moderate to severe hepatocellular degeneration around the portal vein, aggregation of inflammatory cells, granulomatosis, cytolytic necrosis, periportal space fibrosis, and sinusoidal dilatation. However, liver damages were amended by the silymarin. In line with molecular study, a remarkable down-regulation was detected in the expression of CAT, GPx, and Mn-SOD hepatic genes in CCl₄-challenged birds, whereas silymarin significantly up-regulated aforementioned genes. In general, current study showed that silymarin has potential to alleviate the adverse effects of oxidative stress in poultry farms.

Ability of prebiotic polysaccharides to activate a HIF1α-antimicrobial peptide axis determines liver injury risk in zebrafish

Natural polysaccharides have received much attention for their ability to ameliorate hepatic steatosis induced by high-fat diet. However, the potential risks of their use have been less investigated. Here, we show that the exopolysaccharides (EPS) from Lactobacillus rhamnosus GG (LGG) and L. casei BL23 reduce hepatic steatosis in zebrafish fed a high-fat diet, while BL23 EPS, but not LGG EPS, induce liver inflammation and injury. This is due to the fact that BL23 EPS induces gut microbial dysbiosis, while LGG EPS promotes microbial homeostasis. We find that LGG EPS, but not BL23 EPS, can directly activate intestinal HIF1α, and increased HIF1α boosts local antimicrobial peptide expression to facilitate microbial homeostasis, explaining the distinct compositions of LGG EPS- and BL23 EPS-associated microbiota. Finally, we find that liver injury risk is not confined to Lactobacillus-derived EPS but extends to other types of commonly used natural polysaccharides, depending on their HIF1α activation efficiency.

A combination of Pueraria lobata and Silybum marianum protects against alcoholic liver disease in mice

BACKGROUND

Excess alcohol exposure leads to alcoholic liver disease (ALD). Pueraria lobata (PUE) and Silybum marianum (SIL) are two well-known hepatoprotective herbal remedies with various activities. The possible effect of combination of PUE and SIL on ALD has not been elucidated yet.

PURPOSE

We aimed to demonstrate that the combination of PUE and SIL prevents against alcoholic liver injury in mice using a model of chronic-plus-single-binge ethanol feeding.

STUDY DESIGN

Male C57BL/6 mice were randomly divided into five groups (n = 8-10), namely the control group (CON), ethanol-induced liver injury group (ETH), 150 mg/kg PUE treated group (PUE), 60 mg/kg SIL treated group (SIL), 210 mg/kg PUE+SIL treatment group (PUE+SIL). Except control group, all animals were fed a modified Lieber-DeCarli ethanol liquid diet for 10 days. While, control group received Lieber-DeCarli control diet containing isocaloric maltose dextrin substituted for ethanol. On day 11, the mice orally received a single dose of 31.5% (v/v) ethanol (5 g/kg BW) or an isocaloric maltose solution.

RESULTS

Ethanol exposure caused liver injury, as demonstrated by remarkably increased plasma parameters, histopathological changes, the increased lipid accumulation, oxidative stress and inflammation in liver. These alterations were ameliorated by the treatments of PUE, SIL and PUE+SIL. While, the PUE+SIL treatment showed the most effective protection, which was associated with reducing alcohol-induced hepatic steatosis via upregulating LKB1/AMPK/ACC signaling, and inhibiting hepatic inflammation via LPS-triggered TLR4-mediated NF-κB signaling pathway. Our results also indicated that the hepatoprotective effects of SIL+PUE might mainly attribute to the protection of SIL and PUE alone in alcohol-induced hepatic steatosis and hepatic inflammation, respectively.

CONCLUSION

These findings also suggest that the combination of PUE and SIL has a potential to be developed as a functional food for the management of ALD.

Sirtuin3 deficiency exacerbates carbon tetrachloride-induced hepatic injury in mice

Sirtuin3 (SIRT3) plays an important role in maintaining normal mitochondrial function and alleviating oxidative stress. After carbon tetrachloride (CCl₄ ) administration, the expression of SIRT3 decreased in the liver of mice, which indicated that the SIRT3 might play a crucial role during chemical-induced acute hepatic injury. To verify the hypothesis, CCl ₄ was given to induce acute hepatic injury in SIRT3 knockout (KO) mice and wild-type (WT) mice. CCl ₄ -induced liver injury was more severe in SIRT3 KO mice compared with the WT mice. In addition, the oxidative stress induced by CCl ₄ was enhanced in the SIRT3 KO mice. Furthermore, the increased expression of dynamin-related protein 1 was also aggravated in SIRT3 KO mice after CCl ₄ administration. In conclusion, our study demonstrated that SIRT3 deficiency exacerbated CCl ₄ -induced impairment of the liver in mice, and the mechanism might be related to enhanced oxidative stress.