Morin reduces hepatic inflammation-associated lipid accumulation in high fructose-fed rats via inhibiting sphingosine kinase 1/sphingosine 1-phosphate signaling pathway

Polyphenols synergistic drugs to ameliorate non-alcoholic fatty liver disease via signal pathway and gut microbiota: A review

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease with an increasing incidence worldwide. Single drug therapy may have toxic side effects and disrupt gut microbiota balance. Polyphenols are widely used in disease intervention due to their distinctive nutritional properties and medicinal value, which a potential gut microbiota modulator. However, there is a lack of comprehensive review to explore the efficacy and mechanism of combined therapy with drugs and polyphenols for NAFLD.

AIM OF REVIEW

Based on this, this review firstly discusses the link between NAFLD and gut microbiota, and outlines the effects of polyphenols and drugs on gut microbiota. Secondly, it examined recent advances in the treatment and intervention of NAFLD with drugs and polyphenols and the therapeutic effect of the combination of the two. Finally, we highlight the underlying mechanisms of polyphenol combined drug therapy in NAFLD. This is mainly in terms of signaling pathways (NF-κB, AMPK, Nrf2, JAK/STAT, PPAR, SREBP-1c, PI3K/Akt and TLR) and gut microbiota. Furthermore, some emerging mechanisms such as microRNA potential biomarker therapies may provide therapeutic avenues for NAFLD.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Drawing inspiration from combination drug strategies, the use of active substances in combination with drugs for NAFLD intervention holds transformative and prospective potential, both improve NAFLD and restore gut microbiota balance while reducing the required drug dosage. This review systematically discusses the bidirectional interactions between gut microbiota and NAFLD, and summarizes the potential mechanisms of polyphenol synergistic drugs in the treatment of NAFLD by modulating signaling pathways and gut microbiota. Future researches should develop multi-omics technology to identify patients who benefit from polyphenols combination drugs and devising individualized treatment plans to enhance its therapeutic effect.

Impact of micronutrients and nutraceuticals on cognitive function and performance in Alzheimer's disease

Alzheimer's disease (AD) is a major global health problem today and is the most common form of dementia. AD is characterized by the formation of β-amyloid (Aβ) plaques and neurofibrillary clusters, leading to decreased brain acetylcholine levels in the brain. Another mechanism underlying the pathogenesis of AD is the abnormal phosphorylation of tau protein that accumulates at the level of neurofibrillary aggregates, and the areas most affected by this pathological process are usually the cholinergic neurons in cortical, subcortical, and hippocampal areas. These effects result in decreased cognitive function, brain atrophy, and neuronal death. Malnutrition and weight loss are the most frequent manifestations of AD, and these are also associated with greater cognitive decline. Several studies have confirmed that a balanced low-calorie diet and proper nutritional intake may be considered important factors in counteracting or slowing the progression of AD, whereas a high-fat or hypercholesterolemic diet predisposes to an increased risk of developing AD. Especially, fruits, vegetables, antioxidants, vitamins, polyunsaturated fatty acids, and micronutrients supplementation exert positive effects on aging-related changes in the brain due to their antioxidant, anti-inflammatory, and radical scavenging properties. The purpose of this review is to summarize some possible nutritional factors that may contribute to the progression or prevention of AD, understand the role that nutrition plays in the formation of Aβ plaques typical of this neurodegenerative disease, to identify some potential therapeutic strategies that may involve some natural compounds, in delaying the progression of the disease.

Combination therapy of metformin and morin attenuates insulin resistance, inflammation, and oxidative stress in skeletal muscle of high-fat diet-fed mice

Lipid accumulation, inflammation, and oxidative stress are the most important causes of muscle insulin resistance. The aim of this study was to investigate the single and combined treatment effects of metformin (MET) and morin (MOR) on lipid accumulation, inflammation, and oxidative stress in the skeletal muscle of mice fed a high-fat diet. The mice were supplemented with MET (230 mg/kg diet), MOR (100 mg/kg diet), and MET + MOR for 9 weeks. Our results revealed that single treatment with MET or MOR, and with a stronger effect of MET + MOR combined treatment, reduced body weight gain, improved glucose intolerance and enhanced Akt phosphorylation in the muscle tissue. In addition, plasma and muscle triglyceride levels were decreased after treatment with MET and MOR. The expression of genes involved in macrophage infiltration and polarization and pro-inflammatory cytokines showed that MET + MOR combined treatment, significantly reduced inflammation in the muscle. Furthermore, combined treatment of MET + MOR with greater efficacy than the single treatment improved several oxidative stress markers in the muscle. Importantly, combined treatment of MET and MOR could increase the expression of nuclear factor erythroid 2-related factor 2, the master regulator of the antioxidant response. These findings suggest that combination of MET with MOR might ameliorate insulin resistance, inflammation, and oxidative stress in the skeletal muscle of mice fed high-fat diet.

Effect of FTY720P on lipid accumulation in HEPG2 cells

Nonalcoholic fatty liver disease (NAFLD) is characterized by an increase in hepatic lipid accumulation due to impaired lipid metabolism. Although a correlation was found between NAFLD and sphingosine-1-phosphate (S1P), the role of the sphingolipid remains controversial. The aim of this study was to investigate any involvement of S1P in steatosis using its analog FTY720P and HepG2 cells. Lipid accumulation was induced by incubating the cells in a mixture of oleic and palmitic acid, and was quantified using Oil Red O. The involvement of signaling mediators was studied using pharmacological inhibitors and western blot analysis. FTY720P increased lipid accumulation, but this increase wasn't maintained in the presence of inhibitors of S1PR3, Gq, SREBP, mTOR, PI3K, and PPARγ indicating their involvement in the process. The results revealed that FTY720P binds to S1PR3 which activates sequentially Gq, PI3K, and mTOR leading to an increase in SREBP expression and PPARγ activation. It was concluded that in presence of a high level of fatty acids, lipid accumulation is increased in hepatocytes by the exogenously added FTY720P.

Effects of Calendula officinalis extract on liver histopathology, lipid profile, and oxidative stress in rats submitted to a diet rich in cholesterol and carbohydrates

PURPOSE

To evaluate the modulatory properties of Calendula officinalis L. (Asteraceae) (C. officinalis) extract on cafeteria diet-fed rats.

METHODS

A cafeteria diet was administered ad libitum for 45 days to induce dyslipidemia. Then, the rats were treated with the formulations containing C. officinalis in the doses of 50, 100, and 150 mg/kg or only with the vehicle formulation; the control group received a commercial ration.

RESULTS

The cafeteria diet decreased glutathione S-transferase activity and high-density lipoprotein plasmatic levels and damaged the hepatic architecture. The C. officinalis extract was able to reduce lipid infiltration in liver tissue and to modulate oxidative stress and lipid profile markers.

CONCLUSIONS

The correlations between the variables suggest a pathological connection between oxidative stress markers and serum lipid profile.

Integrative roles of sphingosine kinase in liver pathophysiology

Bioactive sphingolipids and enzymes that metabolize sphingolipid-related substances have been considered as critical messengers in various signaling pathways. One such enzyme is the crucial lipid kinase, sphingosine kinase (SphK), which mediates the conversion of sphingosine to the potent signaling substance, sphingosine-1-phosphate. Several studies have demonstrated that SphK metabolism is strictly regulated to maintain the homeostatic balance of cells. Here, we summarize the role of SphK in the course of liver disease and illustrate its effects on both physiological and pathological conditions of the liver. SphK has been implicated in a variety of liver diseases, such as steatosis, liver fibrosis, hepatocellular carcinoma, and hepatic failure. This study may advance the understanding of the cellular and molecular foundations of liver disease and establish therapeutic approaches via SphK modulation.

Roles of pyroptosis in intervertebral disc degeneration

Intervertebral disc degeneration (IDD), the key pathological process in low back pain, is characterized by chronic inflammation and progressive cell death. Pyroptosis is a type of pro-inflammatory programmed necrosis mediated by inflammasomes that is dependent on the gasdermin family of proteins. An in-depth study of the pathological mechanisms of IDD has revealed that pyroptosis plays an important role in its occurrence and development. The molecular characteristics and activation signaling mechanisms of pyroptosis are reviewed in this paper. Moreover, the specific roles of pyroptosis in IDD pathology are outlined and various targeted drugs for its treatment are highlighted.

Lipidomics in pathogenesis, progression and treatment of nonalcoholic steatohepatitis (NASH): Recent advances

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease affecting up to 30% of the general adult population. NAFLD encompasses a histological spectrum ranging from pure steatosis to non-alcoholic steatohepatitis (NASH). NASH can progress to cirrhosis and is becoming the most common indication for liver transplantation, as a result of increasing disease prevalence and of the absence of approved treatments. Lipidomic readouts of liver blood and urine samples from experimental models and from NASH patients disclosed an abnormal lipid composition and metabolism. Collectively, these changes impair organelle function and promote cell damage, necro-inflammation and fibrosis, a condition termed lipotoxicity. We will discuss the lipid species and metabolic pathways leading to NASH development and progression to cirrhosis, as well as and those species that can contribute to inflammation resolution and fibrosis regression. We will also focus on emerging lipid-based therapeutic opportunities, including specialized proresolving lipid molecules and macrovesicles contributing to cell-to-cell communication and NASH pathophysiology.

Raspberry ketone improves non-alcoholic fatty liver disease induced in rats by modulating sphingosine kinase/sphingosine-1-phosphate and toll-like receptor 4 pathways

OBJECTIVES

To investigate the therapeutic role of calorie-restricted diet (CR) and raspberry ketone (RK) in non-alcoholic fatty liver disease (NAFLD) and the implication of sphingosine kinase-1 (SphK1)/sphingosine-1-phosphate (S1P) and toll-like receptor 4 (TLR4) signalling.

METHODS

NAFLD was induced by feeding rats high-fat-fructose-diet (HFFD) for 6 weeks. Rats were then randomly assigned to three groups (n = 6 each); NAFLD group continued on HFFD for another 8 weeks. CR group was switched to CR diet (25% calorie restriction) for 8 weeks and RK group was switched to normal diet and received RK (55 mg/kg/day; orally) for 8 weeks. Another six rats were used as normal control.

KEY FINDINGS

HFFD induced a state of NAFLD indicated by increased fat deposition in liver tissue along with dyslipidemia, elevated liver enzymes, oxidative stress and inflammation. Either CR diet or RK reversed these changes and decreased HFFD-induced elevation of hepatic SphK1, S1P, S1PR1 and TLR4. Of notice, RK along with a normal calorie diet was even better than CR alone in most studied parameters.

CONCLUSIONS

SphK1/S1P and TLR4 are interconnected and related to the establishment of HFFD-induced NAFLD and can be modulated by RK. Supplementation of RK without calorie restriction to patients with NAFLD unable to follow CR diet to achieve their treatment goals would be a promising therapeutic modality.

The combination of metformin with morin alleviates hepatic steatosis via modulating hepatic lipid metabolism, hepatic inflammation, brown adipose tissue thermogenesis, and white adipose tissue browning in high-fat diet-fed mice

AIM

The valuable effects of metformin (MET) and morin (MOR) in the improvement of NAFLD have been proposed, nevertheless, their combination impacts were not investigated so far. We determined the therapeutic effects of combined MET and MOR treatment in high-fat diet (HFD)-induced Non-alcoholic fatty liver disease (NAFLD) mice.

METHODS

C57BL/6 mice were fed on an HFD for 15 weeks. Animals were allotted into various groups and supplemented with MET (230 mg/kg), MOR (100 mg/kg), and MET + MOR (230 mg/kg + 100 mg/kg).

KEY FINDINGS

MET in combination with MOR reduced body and liver weight in HFD-fed mice. A significant decrease in fasting blood glucose and improvement in glucose tolerance was observed in HFD mice treated with MET + MOR. Supplementation with MET + MOR led to a decline in hepatic triglyceride levels and this impact was associated with diminished expression of fatty-acid synthase (FAS) and elevated expression of carnitine palmitoyl transferase 1 (CPT1) and phospho-Acetyl-CoA Carboxylase (p-ACC). Moreover, MET combined with MOR alleviates hepatic inflammation through the polarization of macrophages to the M2 phenotype, decreasing the infiltration of macrophages and lowering the protein level of NF-kB. MET and MOR in combination reduce the size and weight of epididymal white adipose tissue (eWAT), and subcutaneous WAT (sWAT), whereas improves cold tolerance, BAT activity, and mitochondrial biogenesis. Combination therapy results in stimulating brown-like adipocyte (beige) formation in the sWAT of HFD mice.

SIGNIFICANCE

These results suggest that the combination of MET and MOR has a protective effect on hepatic steatosis, which may use as a candidate therapeutic for the improvement of NAFLD.

Dietary Supplementation with Resveratrol Attenuates Serum Melatonin Level, Pro-Inflammatory Response and Metabolic Disorder in Rats Fed High-Fructose High-Lipid Diet under Round-the-Clock Lighting

This study aims to investigate the effect of resveratrol on systemic inflammatory response and metabolic disorder in rats fed a high-fructose high-lipid diet (HFHLD) and exposed to round-the-clock lighting (RCL). 21 adult male Wistar rats were randomly divided into 3 groups: control (group 1, n = 7); HFHLD for 8 weeks + round-the-clock lighting (RCL) (group 2, n = 7); HFHLD + RCL + Resveratrol (in a daily dose of 5 mg/kg intragastrically (group 3, n = 7). Results show that the combined effect of HFHLD and RCL reduces the serum melatonin (p < 0.001) and accelerates pro-inflammatory activities, oxidative stress, and metabolic disorder. There is a significant increase in the serum tumour necrosis factor-alpha (TNF-α) and C-reactive protein (CRP) (both p < 0.001), blood malondialdehyde-thiobarbituric acid adducts (MDA-TBA₂) (p < 0.001), serum glucose (p < 0.01), insulin concentration, and the homeostatic model assessment insulin resistance (HOMA-IR) index (both p < 0.001), serum with very low-density lipoprotein (VLDL), and triacylglycerol (TAG) (both p < 0.001). At the same time, the decrease in the serum high-density lipoprotein (HDL) level (p < 0.001) is observed in the HFHLD + RCL group compared to the control. In the HFHLD + RCL + Resveratrol group, hypomelatonaemia (p < 0.001), pro-inflammatory actions, oxidative stress, and metabolic disorder were mitigated. Resveratrol can cause a significant rise in the serum melatonin and reduce serum TNF-α and CRP levels (both p < 0.001), blood MDA-TBA₂ (p < 0.001), serum glucose (both p < 0.01), insulin concentration, and HOMA-IR (both p < 0.001), serum VLDL and TAG (both p < 0.001) compared to the group 2, while serum HDL level increases (p < 0.01). Resveratrol attenuates pro-inflammatory responses and prevents considerable metabolic disorder in rats fed HFHLD under RCL.

Excessive intake of sugar: An accomplice of inflammation

High sugar intake has long been recognized as a potential environmental risk factor for increased incidence of many non-communicable diseases, including obesity, cardiovascular disease, metabolic syndrome, and type 2 diabetes (T2D). Dietary sugars are mainly hexoses, including glucose, fructose, sucrose and High Fructose Corn Syrup (HFCS). These sugars are primarily absorbed in the gut as fructose and glucose. The consumption of high sugar beverages and processed foods has increased significantly over the past 30 years. Here, we summarize the effects of consuming high levels of dietary hexose on rheumatoid arthritis (RA), multiple sclerosis (MS), psoriasis, inflammatory bowel disease (IBD) and low-grade chronic inflammation. Based on these reported findings, we emphasize that dietary sugars and mixed processed foods may be a key factor leading to the occurrence and aggravation of inflammation. We concluded that by revealing the roles that excessive intake of hexose has on the regulation of human inflammatory diseases are fundamental questions that need to be solved urgently. Moreover, close attention should also be paid to the combination of high glucose-mediated immune imbalance and tumor development, and strive to make substantial contributions to reverse tumor immune escape.

Neuroprotective Effect of Morin Hydrate against Attention-Deficit/Hyperactivity Disorder (ADHD) Induced by MSG and/or Protein Malnutrition in Rat Pups: Effect on Oxidative/Monoamines/Inflammatory Balance and Apoptosis

Monosodium glutamate (MSG) is one of the most widely used food additives. However, it has been linked to protein malnutrition (PM) and various forms of toxicities such as metabolic disorders and neurotoxic effects. The current study is the first to explore the association between MSG, PM, and induced brain injury similar to attention-deficit/hyperactivity disorder (ADHD). Moreover, we determined the underlying mechanistic protective pathways of morin hydrate (MH)―a natural flavonoid with reported multiple therapeutic properties. PM was induced by feeding animals with a low protein diet and confirmed by low serum albumin measurement. Subsequently, rat pups were randomized into seven groups of 10 rats each. Group I, III, and VI were normally fed (NF) and groups II, IV, V, and VII were PM fed. Group I served as normal control NF while Group II served as PM control animals. Group III received NF + 0.4 g/kg MSG, Group IV: PM + 0.4 g/kg MSG, Group V: PM + 60 mg/kg MH, Group VI: NF + 0.4 kg/g MSG + 60 mg/kg MH and Group VII: PM + 0.4 kg/kg MSG + 60 mg/kg MH. At the end of the experimental period, animals were subjected to behavioral and biochemical tests. Our results showed that treatment of rats with a combination of MSG + PM-fed exhibited inferior outcomes as evidenced by deteriorated effects on behavioral, neurochemical, and histopathological analyses when compared to rats who had received MSG or PM alone. Interestingly, MH improved animals’ behavior, increased brain monoamines, brain-derived neuroprotective factor (BDNF), antioxidant status and protein expression of Nrf2/HO-1. This also was accompanied by a significant decrease in brain MDA, inflammatory markers (NF-kB, TNF-α and IL1β), and suppression of TLR4/NLRP3/caspase-1 axis. Taken together, MSG and/or PM are associated with neuronal dysfunction. Our findings suggest MH as a potential neuroprotective agent against brain insults via targeting Nrf2/HO-1 and hindering TLR4/NLRP3 inflammasome signaling pathways.

Investigating Polyphenol Nanoformulations for Therapeutic Targets against Diabetes Mellitus

Diabetes mellitus (DM) is a fatal metabolic disorder, and its prevalence has escalated in recent decades to a greater extent. Since the incidence and severity of the disease are constantly increasing, plenty of therapeutic approaches are being considered as a promising solution. Many dietary polyphenols have been reported to be effective against diabetes along with its accompanying vascular consequences by targeting multiple therapeutic targets. Additionally, the biocompatibility of these polyphenols raises questions about their use as pharmacological mediators. Nevertheless, the pharmacokinetic and biopharmaceutical properties of these polyphenols limit their clinical benefit as therapeutics. Pharmaceutical industries have attempted to improve compliance and therapeutic effects. However, nanotechnological approaches to overcome the pharmacokinetic and biopharmaceutical barriers associated with polyphenols as antidiabetic medications have been shown to be effective to improve clinical compliance and efficacy. Therefore, this review highlighted a comprehensive and up-to-date assessment of polyphenol nanoformulations in the treatment of diabetes and vascular consequences.

You aren't IMMUNE to the ceramides that accumulate in cardiometabolic disease

Obesity leads to persistent increases in immune responses that contribute to cardiometabolic pathologies such as diabetes and cardiovascular disease. Pro-inflammatory macrophages infiltrate the expanding fat mass, which leads to increased production of cytokines such as tumor necrosis factor-alpha. Moreover, saturated fatty acids enhance signaling through the toll-like receptors involved in innate immunity. Herein we discuss the evidence that ceramides-which are intermediates in the biosynthetic pathway that produces sphingolipids-are essential intermediates that link these inflammatory signals to impaired tissue function. We discuss the mechanisms linking these immune insults to ceramide production and review the numerous ceramide actions that alter cellular metabolism, induce oxidative stress, and stimulate apoptosis. Lastly, we evaluate the correlation of ceramides in humans with inflammation-linked cardiometabolic disease and discuss preclinical studies which suggest that ceramide-lowering interventions may be an effective strategy to treat or prevent such maladies.

The docosahexaenoic acid derivatives, diHEP-DPA and TH-DPA, synthesized via recombinant lipoxygenase, ameliorate disturbances in lipid metabolism and liver inflammation in high fat diet-fed mice

7S,15R-Dihydroxy-16S,17S-epoxy-docosapentaenoic acid (diHEP-DPA) and 7S,15R,16S,17S-tetrahydroxy-docosapentaenoic acid (TH-DPA) are two novel lipid mediators derived from docosahexaenoic acid (DHA) that we previously synthesized via combined enzymatic and chemical reactions. In the present study, we investigated the effects of these compounds on disturbances in lipid metabolism and liver inflammation induced by a high fat diet (HFD) in mice. Male BALB/c mice were randomly divided into four groups (n = 10/group): controls, HFD only, HFD + diHEP-DPA, and HFD + TH-DPA. Mice in HFD + diHEP-DPA and HFD + TH-DPA groups were orally administered 20 μg/kg of diHEP-DPA or TH-DPA, respectively. Measurements of adipose accumulation and liver inflammation showed that both diHEP-DPA and TH-DPA decreased adipose tissue mass and liver color depth, as well as total cholesterol, triglycerides, and low-density lipoprotein-cholesterol in the serum of HFD-fed mice compared with mice in the HFD-only group, while elevating high-density lipoprotein-cholesterol. Both of them also decreased hepatic expression of genes encoding lipid synthesis-related proteins (PPARγ, SIRT1, SREBP-1c and FASN) and increased the expression of genes encoding proteins involved in lipid degradation (PPARα and CPT-1) in the liver. Western blotting and quantitative RT-PCR confirmed that diHEP-DPA or TH-DPA administration modulated the expression of inflammation-related genes (TNF-α and IL-6) and inhibited activation of the NF-κB signaling pathway in livers of HFD-fed mice. Taken together, our data indicate that diHEP-DPA and TH-DPA ameliorate liver inflammation and inhibit HFD-induced obesity in mice.

Evaluation of hypoglycemic therapeutics and nutritional supplementation for type 2 diabetes mellitus management: An insight on molecular approaches

OBJECTIVE

This review aims to summarize the current management of type 2 diabetes principles, including oral hypoglycemic agents, types of insulin administration, diet maintenance, and various molecular approaches.

METHODS

A literature search was conducted in different databases such as Scopus, ScienceDirect, Google Scholar, and Web of Science by using the following keywords: type-2 diabetes mellitus (T2DM), first-line and second-line treatment, oral hypoglycemic agents, insulin administration, diet/nutritional therapy, gene and stem cell therapy, and diabetic complications.

RESULTS

The first-line treatment of T2DM includes administering oral hypoglycemic agents (OHAs) and second-line treatment by insulin therapy and some OHAs like Sulfonylurea's (SU). The oral hypoglycemic or oral antidiabetic drugs have the function of lowering glucose in the blood. Insulin therapy is recommended for people with A1C levels > 7.0, and insulin administration is evolved drastically from the syringe, pump, pen, inhalation, insulin jet, and patch. The use of OHAs and insulin therapy during glycemic control has a severe effect on weight gain and other side effects. Hence, diet maintenance (macro and micronutrients) and nutritional therapy guidelines were also reviewed/recommended for safe T2DM management. Besides, the recent progress in molecular approaches that focuses on identifying new targets for T2DM (i.e.) consisting of gene therapy, stem cell therapy, and the modulation of insulin signaling pathways for the regulation of glucose storage and uptake also discussed.

CONCLUSION

The analysis of all these key factors is necessary to develop a potential agent to cure T2DM and suggest that a combination of therapies will pave the way for advanced management of T2DM.

Ethnobotanical, phytochemical, toxicology and anti-diabetic potential of Senna occidentalis (L.) link; A review

ETHNOPHARMACOLOGICAL RELEVANCE

Senna occidentalis (L.) Link is a plant that has been used in medicine in some African countries, Asia and America. It is mainly used in Ayurvedic medicine in India. Several parts of this plant are used for preventing or treating diabetes, haematuria, rheumatism, typhoid, asthma, hepatotoxicity, disorders of haemoglobin and leprosy.

AIM OF THE STUDY

This review outlines the pharmacological evidence supporting the potential of S. occidentalis to control or compensate for diabetes and associated complications, with intentions to sensitize the scientific community for future research on this promising plant.

MATERIALS AND METHODS

Information on the anti-diabetic pharmacological studies of Senna occidentalis was collected from various scientific databases including Scopus, PubMed, ScienceDirect and Google Scholar. The studies were analyzed for the toxicological, phytochemical, anti-diabetic, hypoglycemic, anti-hyperlipidemia and antioxidative aspects of the different parts of S. occidentalis.

RESULTS

Numerous phytochemical constituents (flavonoids, saponins, alkaloids, tannins, terpenes and glycosides) are present in this plant and are responsible for their anti-diabetic, hypoglycemic, anti-hyperlipidemic and antioxidative effects. The different plant parts appears to exert anti-diabetic effects by direct regulation of blood glucose, modulation of lipid profile and improving of antioxidant status and islet function.

CONCLUSION

Senna occidentalis is rich in phytochemicals. The crude extracts of the different parts have valuable bioactive properties with potential ethnopharmacological relevance for diabetes management and treatment. Further bioassay guided phytochemical analyses of this plant are recommended to explore its therapeutic bioactive principles.

Analysis of the Sphingolipidome in NAFLD

The relationship between sphingolipid levels and NAFLD pathology has been recognized for some time. Numerous studies using pharmacological and genetic approaches in vitro and in animal models of NAFLD have demonstrated that modifications to sphingolipid metabolism can attenuate various facets of NAFLD pathology. However, a more precise understanding of the role of sphingolipids and NAFLD pathology is essential to creating therapeutics that target this pathway. This chapter touches on the scale and variety of sphingolipid metabolites at play in NAFLD, which vary widely in their chemical structures and biological functions. With advances in liquid chromatography and tandem mass spectrometry approaches, each of thousands of individual sphingolipid species and sphingolipid metabolites can be identified and precisely quantified. These approaches are beginning to reveal specific sub-classes and species of sphingolipids that change in NAFLD, and as such, enzymes that generate them can be identified and potentially serve as therapeutic targets. Advances in lipidomics technology have been, and will continue to be, critical to these gains in our understanding of NAFLD.

Peach Kernel Extracts Inhibit Lipopolysaccharide-Induced Activation of HSC-T6 Hepatic Stellate Cells

There is an important role for hepatic stellate cells (HSCs) in liver fibrosis. As it stands, many traditional Chinese medicine formulations can effectively improve liver fibrosis, whether it is clinically used or in animal studies; however, the efficacy and mechanism of the main formulations remain unclear, including the peach kernel, which contains numerous phytochemicals with a wide range of biological activities. The purpose of this study was to investigate peach kernel's anti-liver fibrosis effects. In this study, peach kernel extracts inhibited lipopolysaccharide (LPS) activation in HSC-T6 cells and the expression of α-smooth muscle actin and connective tissue growth factor induced by LPS in HSC-T6 cells. Furthermore, peach kernel extracts inhibited signal transducers involving protein kinase B and mitogen-activated protein kinase, which regulate downstream genes associated with inflammation. As a result, peach kernel extracts inhibited inflammatory responses and subsequently inhibited LPS-induced transformation of activated HSC-T6 cells.

Morin attenuates memory deficits in a rat model of Alzheimer's disease by ameliorating oxidative stress and neuroinflammation

This study aimed to investigate the effect of flavonoid morin on oxidative/nitrosative stress, neuroinflammation, and histological, molecular, and behavioral changes caused by amyloid-beta (Aβ)_1-42 in male Wistar rats (Alzheimer's disease model). Rats received morin (20 mg/kg, oral gavage) for 14 consecutive days after intrahippocampal injection of Aβ_1-42. Morin decreased the levels of malondialdehyde and nitric oxide, increased glutathione content, and enhanced catalase activity in the hippocampus of animals receiving Aβ_1-42. It also reduced the expression of tumor necrosis factor-α, interleukin-1β, interleukin-6, nuclear factor-kappa B, and N-methyl-D-aspartate receptor subunits 2A and 2B and increased the expression of brain-derived neurotrophic factor and α7 nicotinic acetylcholine receptor in the hippocampus of Aβ_1-42-injected rats. Besides, morin modified neuronal loss and histological changes in the CA1 region of the hippocampus. Morin allowed Aβ_1-42-infused rats to swim more time in the target quadrant in the Morris water maze test. It is concluded that morin may be suitable for the prevention and treatment of Alzheimer's disease by strengthening the antioxidant system, inhibiting neuroinflammation, preventing neuronal death, and enhancing memory function.

Morin attenuates pyroptosis of nucleus pulposus cells and ameliorates intervertebral disc degeneration via inhibition of the TXNIP/NLRP3/Caspase-1/IL-1β signaling pathway

Intervertebral disc degeneration (IDD) is a major cause of lower back pain (LBP), a condition that causes a heavy economic burden globally. The production of cytokines, including interleukin (IL)-1β and tumor necrosis factor (TNF) α, is increased in the degenerating intervertebral disc. Thioredoxin-interacting protein (TXNIP) participates in NLRP3 inflammasome-dependent pyroptosis in liver. Therefore, we hypothesized that TXNIP maypromote pyroptosis via NLRP3/Caspase-1/IL-1β signaling pathway in nucleus pulposus (NP) cell. This study examined the effects of TXNIP on IDD, explored the underlying mechanisms of action and find Morin which is the inhibitor of TXNIP can attenuates pyroptosis of nucleus pulposus cells and ameliorates intervertebral disc degeneration. Our findings indicate that TXNIP promote pyroptosis via NLRP3/Caspase-1/IL-1β signaling pathway in NP cell. Morin considerably inhibited the TXNIP/NLRP3/Caspase-1 signaling pathway in vitro. In vivo. Our data show that TXNIP can aggravates intervertebral disc degeneration and morin may be a useful therapeutic agent for IDD.

Altered hepatic sphingolipid metabolism in insulin resistant mice: Role of advanced glycation endproducts

High plasma levels of the sphingolipid intermediates ceramide (Cer) and sphingosine-1-phosphate (S1P) are suggested to be involved in the development of insulin resistance (IR). Recent evidence indicates that advanced glycation endproducts (AGEs) can alter the sphingolipids metabolism equilibrium. Since enzymes responsible for sphingolipid rheostat maintenance are highly expressed in liver, we thus investigated whether AGEs accumulation can affect hepatic sphingolipids metabolism in insulin resistant mice. Two different models of IR were examined: genetically diabetic LeptrDb-/- (DbDb) and diet-induced insulin resistant C57Bl/6J mice fed a 60% trans-fat diet (HFD). In addition, a group of HFD mice was supplemented with the anti-AGEs compound pyridoxamine. AGEs were evaluated in the liver by western blotting. Cer and S1P were measured by UHPLC-MS/MS. The expression of RAGE and of enzymes involved in sphingolipid metabolism were assessed by RT-PCR and western blotting. HepG2 cells were used to study the effect of the major AGE Nε-(carboxymethyl)lysine (CML)-albumin on sphingolipid metabolism and the role of the receptor of AGEs (RAGE). High levels of AGEs and RAGE were detected in the liver of both DbDb and HFD mice in comparison to controls. The expression of enzymes of sphingolipid metabolism was altered in both models, accompanied by increased levels of Cer and S1P. Specifically, ceramide synthase 5 and sphingosine kinase 1 were increased, while neutral ceramidase was reduced. Pyridoxamine supplementation to HFD mice diminished hepatic AGEs and prevented alterations of sphingolipid metabolism and the development of IR. CML administration to HepG2 cells evoked alterations similar to those observed in vivo, that were in part mediated by the binding to RAGE. The present study shows a direct involvement of AGEs in alterations of sphingolipid metabolism associated to the development of IR. The modulation of sphingolipids metabolism through the prevention of AGEs accumulation by pyridoxamine may reduce the development of IR.

Anti-obesity properties and mechanism of action of flavonoids: A review

Obesity is a major public health problem, and there is increasing scientific interest in its mechanisms, as well as a search for new compounds with antioxidant and anti-inflammatory properties that can minimize the metabolic complications associated with its pathology. One potential source of these compounds is natural products; Among these, flavonoids are a promising group of natural substances. Flavonoids are active constituents with diverse biological activities and are widely found in plants kingdom. Numerous studies have shown that flavonoids can effectively inhibit obesity and related metabolic disorders. The review synthesizes recent evidence in respect of progress in the understanding of the anti-obesity effects of flavonoids. Such effects which occurs through the modulation of proteins, genes and transcriptional factors involved in decreasing lipogenesis, increasing lipolysis, expenditure energy, stimulating fatty acids B-oxidation, digestion and metabolism of carbohydrates. In addition to mitigating inflammatory responses and suppress oxidative stress. A better understanding of the modulating effects and mechanisms of flavonoids in relation to obesity will allow us to better use these compounds to treat or even prevent obesity and its associated comorbidities.

Polydatin inhibits ZEB1-invoked epithelial-mesenchymal transition in fructose-induced liver fibrosis

High fructose intake is a risk factor for liver fibrosis. Polydatin is a main constituent of the rhizome of Polygonum cuspidatum, which has been used in traditional Chinese medicine to treat liver fibrosis. However, the underlying mechanisms of fructose-driven liver fibrosis as well as the actions of polydatin are not fully understood. In this study, fructose was found to promote zinc finger E-box binding homeobox 1 (ZEB1) nuclear translocation, decrease microRNA-203 (miR-203) expression, increase survivin, activate transforming growth factor β1 (TGF-β1)/Smad signalling, down-regulate E-cadherin, and up-regulate fibroblast specific protein 1 (FSP1), vimentin, N-cadherin and collagen I (COL1A1) in rat livers and BRL-3A cells, in parallel with fructose-induced liver fibrosis. Furthermore, ZEB1 nuclear translocation-mediated miR-203 low-expression was found to target survivin to activate TGF-β1/Smad signalling, causing the EMT in fructose-exposed BRL-3A cells. Polydatin antagonized ZEB1 nuclear translocation to up-regulate miR-203, subsequently blocked survivin-activated TGF-β1/Smad signalling, which were consistent with its protection against fructose-induced EMT and liver fibrosis. These results suggest that ZEB1 nuclear translocation may play an essential role in fructose-induced EMT in liver fibrosis by targeting survivin to activate TGF-β1/Smad signalling. The suppression of ZEB1 nuclear translocation by polydatin may be a novel strategy for attenuating the EMT in liver fibrosis associated with high fructose diet.

Roles of sarcoplasmic reticulum Ca2+ ATPase pump in the impairments of lymphatic contractile activity in a metabolic syndrome rat model

The intrinsic lymphatic contractile activity is necessary for proper lymph transport. Mesenteric lymphatic vessels from high-fructose diet-induced metabolic syndrome (MetSyn) rats exhibited impairments in its intrinsic phasic contractile activity; however, the molecular mechanisms responsible for the weaker lymphatic pumping activity in MetSyn conditions are unknown. Several metabolic disease models have shown that dysregulation of sarcoplasmic reticulum Ca2+ ATPase (SERCA) pump is one of the key determinants of the phenotypes seen in various muscle tissues. Hence, we hypothesized that a decrease in SERCA pump expression and/or activity in lymphatic muscle influences the diminished lymphatic vessel contractions in MetSyn animals. Results demonstrated that SERCA inhibitor, thapsigargin, significantly reduced lymphatic phasic contractile frequency and amplitude in control vessels, whereas, the reduced MetSyn lymphatic contractile activity was not further diminished by thapsigargin. While SERCA2a expression was significantly decreased in MetSyn lymphatic vessels, myosin light chain 20, MLC20 phosphorylation was increased in these vessels. Additionally, insulin resistant lymphatic muscle cells exhibited elevated intracellular calcium and decreased SERCA2a expression and activity. The SERCA activator, CDN 1163 partially restored lymphatic contractile activity in MetSyn lymphatic vessel by increasing phasic contractile frequency. Thus, our data provide the first evidence that SERCA2a modulates the lymphatic pumping activity by regulating phasic contractile amplitude and frequency, but not the lymphatic tone. Diminished lymphatic contractile activity in the vessels from the MetSyn animal is associated with the decreased SERCA2a expression and impaired SERCA2 activity in lymphatic muscle.

Magnesium isoglycyrrhizinate alleviates fructose-induced liver oxidative stress and inflammatory injury through suppressing NOXs

Excessive fructose intake is a risk factor for liver oxidative stress injury. Magnesium isoglycyrrhizinate as a hepatoprotective agent is used to treat liver diseases in clinic. However, its antioxidant effects and the underlying potential mechanisms are still not clearly understood. In this study, magnesium isoglycyrrhizinate was found to alleviate liver oxidative stress and inflammatory injury in fructose-fed rats. Magnesium isoglycyrrhizinate suppressed hepatic reactive oxygen species overproduction (0.97 ± 0.04 a.u. versus 1.34 ± 0.07 a.u.) in fructose-fed rats by down-regulating mRNA and protein levels of nicotinamide adenine dinucleotide phosphate oxidase (NOX) 1, NOX2 and NOX4, resulting in reduction of interleukin-1β (IL-1β) levels (1.13 ± 0.09 a.u. versus 1.97 ± 0.12 a.u.). Similarly, magnesium isoglycyrrhizinate reduced reactive oxygen species overproduction (1.07 ± 0.02 a.u. versus 1.35 ± 0.06 a.u.) and IL-1β levels (1.14 ± 0.09 a.u. versus 1.66 ± 0.07 a.u.) in fructose-exposed HepG2 cells. Furthermore, data from treatment of reactive oxygen species inhibitor N-acetyl-L-cysteine or NOXs inhibitor diphenyleneiodonium in fructose-exposed HepG2 cells showed that fructose enhanced NOX1, NOX2 and NOX4 expression to increase reactive oxygen species generation, causing oxidative stress and inflammation, more importantly, these disturbances were significantly attenuated by magnesium isoglycyrrhizinate. The molecular mechanisms underpinning these effects suggest that magnesium isoglycyrrhizinate may inhibit NOX1, NOX2 and NOX4 expression to reduce reactive oxygen species generation, subsequently prevent liver oxidative stress injury under high fructose condition. Thus, the blockade of NOX1, NOX2 and NOX4 expression by magnesium isoglycyrrhizinate may be the potential therapeutic approach for improving fructose-induced liver injury in clinic.

Pterostilbene Improves Hepatic Lipid Accumulation via the MiR-34a/Sirt1/SREBP-1 Pathway in Fructose-Fed Rats

High fructose intake promotes hepatic lipid accumulation. Pterostilbene, a natural analogue of resveratrol found in diet berries, exhibits a hepatoprotective property. Here, we studied the protection by pterostilbene against fructose-induced hepatic lipid accumulation and explored its possible mechanism. We observed a high expression of microRNA-34a (miR-34a, P < 0.05) and a low expression of its target, sirtuin1 (Sirt1, mRNA: P < 0.01; protein: P < 0.001), with the overactivation of downstream sterol regulatory element-binding protein-1 (SREBP-1) lipogenic pathway (nuclear SREBP-1 protein: P < 0.05; FAS and SCD1 mRNA: P < 0.01), in rat livers, as well as BRL-3A and HepG2 cells, stimulated by fructose. More interestingly, pterostilbene recovered the fructose-disturbed miR-34a expression (0.3-0.5-fold vs fructose control, P < 0.05), Sirt1 protein level (1.2- to 1.5-fold vs fructose control, P < 0.05), and SREBP-1 lipogenic pathway, resulting in significant amelioration of hepatocyte lipid accumulation in animal [hepatic triglyceride and total cholesterol (TG&TC) mg/g·wet tissue: 4.90 ± 0.19, 5.23 ± 0.16, 5.20 ± 0.29 vs fructose control 9.73 ± 1.06, P < 0.001; 3.18 ± 0.30, 3.31 ± 0.39, 3.37 ± 0.47 vs 5.67 ± 0.28, P < 0.001] and cell models (BRL-3A TG&TC mmol/g·protein: 0.123 ± 0.011 vs 0.177 ± 0.004, P < 0.001; 0.169 ± 0.011 vs 0.202 ± 0.008, P < 0.05; HepG2: 0.257 ± 0.005 vs 0.303 ± 0.016, P < 0.05; 0.143 ± 0.004 vs 0.201 ± 0.008, P < 0.001). These results provide the experimental evidence supporting the anti-lipogenic effect of pterostilbene against fructose-induced hepatic lipid accumulation via modulating the miR-34a/Sirt1/SREBP-1 pathway.

Flavonoids and type 2 diabetes: Evidence of efficacy in clinical and animal studies and delivery strategies to enhance their therapeutic efficacy

Diabetes mellitus type 2 (T2DM) is a metabolic disorder develops due to the overproduction of free radicals where oxidative stress could contribute it. Possible factors are defective insulin signals, glucose oxidation, and degradation of glycated proteins as well as alteration in glutathione metabolism which induced hyperglycemia. Previous studies revealed a link between T2DM with oxidative stress, inflammation and insulin resistance which are assumed to be regulated by numerous cellular networks such as NF-κB, PI3K/Akt, MAPK, GSK3 and PPARγ. Flavonoids are ubiquitously present in the nature and classified according to their chemical structures for example, flavonols, flavones, flavan-3-ols, anthocyanidins, flavanones, and isoflavones. Flavonoids indicate poor bioavailability which could be improved by employing various nano-delivery systems against the occurrences of T2DM. These bioactive compounds exert versatile anti-diabetic activities via modulating targeted cellular signaling networks, thereby, improving glucose metabolism, α -glycosidase, and glucose transport or aldose reductase by carbohydrate metabolic pathway in pancreatic β-cells, hepatocytes, adipocytes and skeletal myofibres. Moreover, anti-diabetic properties of flavonoids also encounter diabetic related complications. This review article has designed to shed light on the anti-diabetic potential of flavonoids, contribution of oxidative stress, evidence of efficacy in clinical, cellular and animal studies and nano-delivery approaches to enhance their therapeutic efficacy. This article might give some new insights for therapeutic intervention against T2DM in near future.

Morin Hydrate Inhibits TREM-1/TLR4-Mediated Inflammatory Response in Macrophages and Protects Against Carbon Tetrachloride-Induced Acute Liver Injury in Mice

This study aims to investigate the protective effects of morin hydrate (MH) against acute liver injury induced by carbon tetrachloride (CCl₄) in mice and to elucidate the possible molecular mechanism of action. Mice were pretreated with MH (50 mg/kg body weight) or vehicle by oral gavage once daily for 5 days, followed by intraperitoneal injection of a single dose of CCl₄ (1 ml/kg in olive oil). Mice were sacrificed 24 h later; the blood and liver samples were harvested for analysis. We also used the model of lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages in vitro and examined the effects of MH and its mechanism of action on the inflammatory response. Our results revealed that MH remarkably attenuated liver histopathological alterations, serum transaminases, hepatocytes death, and inflammatory response induced by CCl₄. Importantly, MH reduced expression of the triggering receptor expressed on myeloid cells-1 (TREM-1) and toll-like receptor 4 (TLR4) both in vivo and in vitro experiments. This inhibitory effect MH on expression of the TREM-1 and TLR4 in cell culture was further heightened after TREM-1 knockdown with small interfering RNA (siRNA). Moreover, MH dramatically suppressed the inhibitor of kappa B α (IκBα) degradation and subsequent nuclear factor-kappa B (NF-κB) p65 translocation into the nucleus and NF-κB-mediated cytokines, such as tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and IL-6. Additionally, MH also ameliorated CCl₄-induced oxidative stress by enhancing the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression in the injured livers. Taken together, MH has hepatoprotective activity, and this effect may be elicited by attenuating macrophage-mediated inflammatory responses via inhibition TREM-1/TLR4/NF-κB signaling and by regulating hepatic oxidative stress via enhancement Nrf2/HO-1 antioxidant pathway.

Flavonoids and Their Anti-Diabetic Effects: Cellular Mechanisms and Effects to Improve Blood Sugar Levels

Diabetes mellitus (DM) is a prevailing global health metabolic disorder, with an alarming incidence rate and a huge burden on health care providers. DM is characterized by the elevation of blood glucose due either to a defect in insulin synthesis, secretion, binding to receptor, or an increase of insulin resistance. The internal and external factors such as obesity, urbanizations, and genetic mutations could increase the risk of developing DM. Flavonoids are phenolic compounds existing as secondary metabolites in fruits and vegetables as well as fungi. Their structure consists of 15 carbon skeletons and two aromatic rings (A and B) connected by three carbon chains. Flavonoids are furtherly classified into 6 subclasses: flavonols, flavones, flavanones, isoflavones, flavanols, and anthocyanidins. Naturally occurring flavonoids possess anti-diabetic effects. As in vitro and animal model's studies demonstrate, they have the ability to prevent diabetes and its complications. The aim of this review is to summarize the current knowledge addressing the antidiabetic effects of dietary flavonoids and their underlying molecular mechanisms on selected pathways: Glucose transporter, hepatic enzymes, tyrosine kinase inhibitor, AMPK, PPAR, and NF-κB. Flavonoids improve the pathogenesis of diabetes and its complications through the regulation of glucose metabolism, hepatic enzymes activities, and a lipid profile. Most studies illustrate a positive role of specific dietary flavonoids on diabetes, but the mechanisms of action and the side effects need more clarification. Overall, more research is needed to provide a better understanding of the mechanisms of diabetes treatment using flavonoids.

Telmisartan and/or chlorogenic acid attenuates fructose-induced non-alcoholic fatty liver disease in rats: Implications of cross-talk between angiotensin, the sphingosine kinase/sphingoine-1-phosphate pathway, and TLR4 receptors

Renin-angiotensin-aldosterone system (RAS) has been implicated in non-alcoholic fatty liver disease (NAFLD); the most common cause of chronic liver diseases. There is accumulating evidence that altered TLR4 and Sphingosine kinase 1(SphK1)/sphingosine1phosphate (S1P) signaling pathways are key players in the pathogenesis of NAFLD. Cross talk of the sphingosine signaling pathway, toll-4 (TLR4) receptors, and angiotensin II was reported in various tissues. Therefore, the aim of this study was to define the contribution of these two pathways to the hepatoprotective effects of telmisartan and/or chlorogenic acid (CGA) in NAFLD. CGA is a strong antioxidant that was previously reported to inhibit angiotensin converting enzyme. Male Wistar rats were treated with either high-fructose, with or without telmisartan, CGA, telmisartan + CGA for 8 weeks. Untreated NAFL rats showed characteristics of NAFLD, as evidenced by significant increase in the body weight, insulin resistance, and serum hepatotoxicity markers (Alanine and Aspartate transaminases) and lipids as compared to the negative control group, in addition to characteristic histopathological alterations. Treatment with either telmisartan and/or CGA improved aforementioned parameters, in addition to upregulation of antioxidant enzymes (Superoxide dismutase and Glutathione peroxidase). Effect of inhibiting RAS on both sphingosine pathway and TLR4 was evident by the suppressing effect of telmisartan and/or CGA on high fructose-induced upregulation of hepatic SPK1 and S1P, in addition to concomitant up-regulation of Sphingosine-1-Phosphate receptor (S1PR)3 protein level and increased expression of S1PR1 and TLR4. As TLR4 and SPK/S1P signaling pathways play important roles in the progression of liver inflammation, the effect on sphingosine pathway and TLR4 was associated with decreased concentrations of inflammatory markers, enzyme kB kinase (IKK), nuclear factor-kB and tumor necrosis factor-α as compared to untreated NAFL group. In conclusion, the present data strongly suggests the cross-talk between angiotensin, the Sphingosine SPK/S1P Axis and TLR4 Receptors, and their role in the pathogenesis of fructose-induced NAFLD, and the protection afforded by drugs inhibiting RAS.

Preventive effect of trans-chalcone on non-alcoholic steatohepatitis: Improvement of hepatic lipid metabolism

Non-alcoholic steatohepatitis (NASH) is an inflammatory and progressive form of non-alcoholic fatty liver disease. However, there are no FDA-approved drugs for this condition. Lipids accumulated in NASH have a direct role in the progression of this disease. Therefore, this study for the first time explored the preventive effect of trans-chalcone on NASH through the modulation of sterol regulatory element binding protein (SREBP)-1c, SREBP-2, hepatic fatty acid synthesis (FAS) enzyme, proliferator-activated receptor (PPAR)-α, and PPAR-γ2 levels, which are involved in hepatic lipid metabolism. In this study, male rats were randomly divided into three groups (n = 7): Control, received 10% tween 80; NASH, received 10% tween 80 and 10 ml/kg high-fat emulsion (high-fat diet, HFD); and NASH + TC, received 20 mg/kg trans-chalcone and 10 ml/kg HFD. All treatments were performed by once-daily oral gavage for 6 weeks. Liver and blood samples were collected and serum levels of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol, as well as hepatic levels of SREBP-1c, SREBP-2, FAS, PPAR-α, and PPAR-γ2, were measured. Moreover, hematoxylin and eosin stained tissues were used for histological analysis. In this study, treatment of HFD-fed rats with trans-chalcone significantly reduced abnormalities in liver histology, serum levels of liver injury markers, liver index, and hepatic levels of SREBP-1c, SREBP-2, FAS, and PPAR-γ2. Furthermore, trans-chalcone significantly increased hepatic PPARα levels in these rats. Therefore, it seems that trans-chalcone protects the liver of HFD-fed rats against NASH development through reduction of SREBP-1c/ FAS- and PPAR-γ2-related lipogenesis, attenuation of SREBP-2-related cholesterol synthesis, and elevation of PPARα-related fatty acid oxidation.

Polydatin prevents fructose-induced liver inflammation and lipid deposition through increasing miR-200a to regulate Keap1/Nrf2 pathway

Oxidative stress is a critical factor in nonalcoholic fatty liver disease pathogenesis. MicroRNA-200a (miR-200a) is reported to target Kelch-like ECH-associated protein 1 (Keap1), which regulates nuclear factor erythroid 2-related factor 2 (Nrf2) anti-oxidant pathway. Polydatin (3,4',5-trihydroxy-stilbene-3-β-D-glucoside), a polyphenol found in the rhizome of Polygonum cuspidatum, have anti-oxidative, anti-inflammatory and anti-hyperlipidemic effects. However, whether miR-200a controls Keap1/Nrf2 pathway in fructose-induced liver inflammation and lipid deposition and the blockade of polydatin are still not clear. Here, we detected miR-200a down-regulation, Keap1 up-regulation, Nrf2 antioxidant pathway inactivation, ROS-driven thioredoxin-interacting protein (TXNIP) over-expression, NOD-like receptor (NLR) family, pyrin domain containing 3 (NLRP3) inflammasome activation and dysregulation of peroxisome proliferator activated receptor-α (PPAR-α), carnitine palmitoyl transferase-1 (CPT-1), sterol regulatory element binging protein 1 (SREBP-1) and stearoyl-CoA desaturase-1 (SCD-1) in rat livers, BRL-3A and HepG2 cells under high fructose induction. Furthermore, the data from the treatment or transfection of miR-200a minic, Keap1 and TXNIP siRNA, Nrf2 activator and ROS inhibitor demonstrated that fructose-induced miR-200a low-expression increased Keap1 to block Nrf2 antioxidant pathway, and then enhanced ROS-driven TXNIP to activate NLRP3 inflammasome and disturb lipid metabolism-related proteins, causing inflammation and lipid deposition in BRL-3A cells. We also found that polydatin up-regulated miR-200a to inhibit Keap1 and activate Nrf2 antioxidant pathway, resulting in attenuation of these disturbances in these animal and cell models. These findings provide a novel pathological mechanism of fructose-induced redox status imbalance and suggest that the enhancement of miR-200a to control Keap1/Nrf2 pathway by polydatin is a therapeutic strategy for fructose-associated liver inflammation and lipid deposition.

UPLC/Q-TOFMS-Based Metabolomics Approach to Reveal the Protective Role of Other Herbs in An-Gong-Niu-Huang Wan Against the Hepatorenal Toxicity of Cinnabar and Realgar

An-Gong-Niu-Huang Wan (AGNH) is a well-known traditional Chinese medicine (TCM) recipe containing cinnabar (HgS) and realgar (As₂S₂). However, the application of AGNH is limited by the hepato- and nephrotoxicity of cinnabar and realgar. It should be noted that cinnabar and realgar in AGNH are not used alone, but rather combined with other herbs as formula to use. In this study, the protective effects and mechanisms of the other herbs in AGNH against the hepatorenal toxicity induced by cinnabar and realgar were investigated. The combination use of the other herbs in AGNH alleviated inflammatory cell infiltration and damage in the liver and kidney and restored the disturbed serum metabolic profile induced by cinnabar and realgar insults. By UPLC/Q-TOFMS combined with pattern recognition approaches, we identified 41 endogenous metabolites in the sera of mice that were related to the hepatorenal toxicity of cinnabar and realgar, 36 of which were restored to normal levels when various kinds of herbs were combined as compound recipe. These metabolites function as modulators in inflammation-associated glycerophospholipid, arachidonic acid, linoleic acid, sphingolipid, and ether lipid metabolic pathways. Notably, lysophosphatidylcholines (LysoPCs) were the most elevated among all of the metabolites detected after cinnabar and realgar treatment, while these LysoPCs did not show overt differences between the AGNH and saline control groups, which was associated with relatively unaffected or even up-regulated expression of lysophosphatidylcholine acyltransferase 1 (LPCAT1) and autotaxin (ATX). These findings indicated that other herbs in AGNH could have a protective effect against cinnabar- and realgar-induced hepatic and renal damage via modulating the disordered homeostasis of the glycerophospholipid, arachidonic acid, linoleic acid, ether lipid, and sphingolipid metabolism.

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.

Divergent Role of Sphingosine 1-Phosphate in Liver Health and Disease

Two decades ago, sphingosine 1-phosphate (S1P) was discovered as a novel bioactive molecule that regulates a variety of cellular functions. The plethora of S1P-mediated effects is due to the fact that the sphingolipid not only modulates intracellular functions but also acts as a ligand of G protein-coupled receptors after secretion into the extracellular environment. In the plasma, S1P is found in high concentrations, modulating immune cell trafficking and vascular endothelial integrity. The liver is engaged in modulating the plasma S1P content, as it produces apolipoprotein M, which is a chaperone for the S1P transport. Moreover, the liver plays a substantial role in glucose and lipid homeostasis. A dysfunction of glucose and lipid metabolism is connected with the development of liver diseases such as hepatic insulin resistance, non-alcoholic fatty liver disease, or liver fibrosis. Recent studies indicate that S1P is involved in liver pathophysiology and contributes to the development of liver diseases. In this review, the current state of knowledge about S1P and its signaling in the liver is summarized with a specific focus on the dysregulation of S1P signaling in obesity-mediated liver diseases. Thus, the modulation of S1P signaling can be considered as a potential therapeutic target for the treatment of hepatic diseases.

High fructose diet-induced metabolic syndrome: Pathophysiological mechanism and treatment by traditional Chinese medicine

Fructose is a natural monosaccharide broadly used in modern society. Over the past few decades, epidemiological studies have demonstrated that high fructose intake is an etiological factor of metabolic syndrome (MetS). This review highlights research advances on fructose-induced MetS, especially the underlying pathophysiological mechanism as well as pharmacotherapy by traditional Chinese medicine (TCM), using the PubMed, Web of science, China National Knowledge Infrastructure, China Science and Technology Journal and Wanfang Data. This review focuses on de novo lipogenesis (DNL) and uric acid (UA) production, two unique features of fructolysis different from glucose glycolysis. High level of DNL and UA production can result in insulin resistance, the key pathological event in developing MetS, mostly through oxidative stress and inflammation. Some other pathologies like the disturbance in brain and gut microbiota in the development of fructose-induced MetS in the past years, are also discussed. In management of MetS, TCM is an excellent representative in alternative and complementary medicine with a complete theory system and substantial herbal remedies. TCMs against MetS or MetS components, including Chinese patent medicines, TCM compound formulas, single TCM herbs and active compounds of TCM herbs, are reviewed on their effects and molecular mechanisms. TCMs with hypouricemic activity, which specially target fructose-induced MetS, are highlighted. And new technologies and strategies (such as high-throughput assay and systems biology) in this field are further discussed. In summary, fructose-induced MetS is a multifactorial disorder with the underlying complex mechanisms. Current clinical and pre-clinical evidence supports the potential of TCMs in management of MetS. Additionally, TCMs may show some advantages against complex MetS as their holistic feature through multiple target actions. However, further work is needed to confirm the effectivity and safety of TCMs by high-standard clinical trials, clarify the molecular mechanisms, and develop new anti-MetS drugs by development and application of optimized and feasible strategies and methods.

The Potential and Action Mechanism of Polyphenols in the Treatment of Liver Diseases

Liver disease, involving a wide range of liver pathologies from fatty liver, hepatitis, and fibrosis to cirrhosis and hepatocellular carcinoma, is a serious health problem worldwide. In recent years, many natural foods and herbs with abundant phytochemicals have been proposed as health supplementation for patients with hepatic disorders. As an important category of phytochemicals, natural polyphenols have attracted increasing attention as potential agents for the prevention and treatment of liver diseases. The striking capacities in remitting oxidative stress, lipid metabolism, insulin resistance, and inflammation put polyphenols in the spotlight for the therapies of liver diseases. It has been reported that many polyphenols from a wide range of foods and herbs exert therapeutic effects on liver injuries via complicated mechanisms. Therefore, it is necessary to have a systematical review to sort out current researches to help better understand the potentials of polyphenols in liver diseases. In this review, we aim to summarize and update the existing evidence of natural polyphenols in the treatment of various liver diseases by in vitro, in vivo, and clinical studies, while special attention is paid to the action mechanisms.

Morin enhances hepatic Nrf2 expression in a liver fibrosis rat model

AIM

To investigate whether morin can reduce hepatic fibrosis by activating the NF-E2-related factor 2 (Nrf2) signaling pathway.

METHODS

Twenty male Sprague-Dawley rats were randomly divided into four groups: control group, morin group, carbon tetrachloride (CCl₄) group, and morin + CCl₄ group. Rats in both the CCl₄ and morin + CCl₄ groups were injected intraperitoneally with CCl₄ at a dose of 2 mL/kg twice a week. Rats in both the morin and morin + CCl₄ groups were treated orally with morin at a dose of 50 mg/kg twice a week. Control rats were treated with vehicle only twice a week. At the end-point of the 8 wk of the experimental period, serum AST, ALT, and ALP were measured, and the liver specimens were obtained for pathological assessment. Real-time PCR and Western blot methods were used to analyze the expression of α-smooth muscle actin (α-SMA), collagen I, collagen III, Nrf2, heme oxygenase (HO-1), and quinone oxidoreductase 1 (NQO1) using frozen liver specimens.

RESULTS

Morin-treated rats in the morin + CCl₄ group had less hyperplasia of fiber tissue, minimal inflammatory cells, and less body weight loss with favorable liver enzyme measurements compared to rats treated with CCl₄ only. Additionally, morin-treated rats had significantly lower mRNA and protein expression of α-SMA, collagen I, and collagen III, but significantly higher mRNA and protein expression of Nrf2, HO-1, and NQO1 compared to rats treated with CCl₄ only (P < 0.05).

CONCLUSION

Morin could play a protective role by inducing the expression of Nrf2 and its downstream antioxidant factors (HO-1 and NQO1) and reducing the expression of α-SMA, collagen I, and collagen III in CCl₄-induced liver fibrosis rats.

Morin, a novel liver X receptor α/β dual antagonist, has potent therapeutic efficacy for nonalcoholic fatty liver diseases

BACKGROUND AND PURPOSE

Morin is a natural occurring flavonoid in many dietary plants and has a wide range of beneficial effects on metabolism; however, the mechanism underlying its action remains elusive.

EXPERIMENTAL APPROACH

A reporter assay and the time-resolved FRET assay were used to identify morin as a dual antagonist of liver X receptor (LXR)-α and -β. Morin (100 mg^. 100 g^-1 diet) was administered to high-fat diet-induced obese or LXRβ^-/- mice. The pharmacological effects and mechanism of action of morin were evaluated by Western blot and RT-PCR analyses.

KEY RESULTS

From the in vitro assays, morin was shown to be a dual antagonist of LXRα and LXRβ. In vivo, morin blunted the development of liver hepatic steatosis, reduced body weight gains, lowered triglyceride levels and improved glucose and insulin tolerance in mice fed a high-fat diet. Mechanistically, morin inhibited 3T3-L1 adipocyte differentiation and lipid formation in human hepatic HepG2 cells and suppressed the mRNA expression of genes downstream of LXR. Consistently, the effects of morin on metabolic disorders were attenuated in LXRβ^-/- mice.

CONCLUSION AND IMPLICATIONS

Our data reveal that morin is a dual antagonist of LXRα and LXRβ and suggest that morin may alleviate hepatic steatosis and other associated metabolic disorders via the suppression of LXR signalling and, therefore, shows promise as a novel therapy or nutraceutical for nonalcoholic fatty liver disease.

Impact of Fish Oil Supplementation and Interruption of Fructose Ingestion on Glucose and Lipid Homeostasis of Rats Drinking Different Concentrations of Fructose

Background. Continuous fructose consumption may cause elevation of circulating triacylglycerol. However, how much of this alteration is reverted after the removal of fructose intake is not known. We explored this question and compared the efficacy of this approach with fish oil supplementation. Methods. Male Wistar rats were divided into the following groups: control (C), fructose (F) (water intake with 10% or 30% fructose for 9 weeks), fish oil (FO), and fructose/fish oil (FFO). Fish oil was supplemented only for the last 33 days of fructose ingestion. Half of the F group remained for additional 8 weeks without fructose ingestion (FR). Results. Fructose ingestion reduced food intake to compensate for the increased energy obtained through water ingestion, independent of fructose concentration. Fish oil supplementation exerted no impact on these parameters, but the removal of fructose from water recovered both ingestion behaviors. Plasma triacylglycerol augmented significantly during the second and third weeks (both fructose groups). Fish oil supplementation did not attenuate the elevation in triacylglycerol caused by fructose intake, but the interruption of sugar consumption normalized this parameter. Conclusion. Elevation in triacylglyceridemia may be recovered by removing fructose from diet, suggesting that it is never too late to repair improper dietary habits.

Sphingosine kinase and sphingosine-1-phosphate in liver pathobiology

Over 20 years ago, sphingosine-1-phosphate (S1P) was discovered to be a bioactive signaling molecule. Subsequent studies later identified two related kinases, sphingosine kinase 1 and 2, which are responsible for the phosphorylation of sphingosine to S1P. Many stimuli increase sphingosine kinase activity and S1P production and secretion. Outside the cell, S1P can bind to and activate five S1P-specific G protein-coupled receptors (S1PR1-5) to regulate many important cellular and physiological processes in an autocrine or paracrine manner. S1P is found in high concentrations in the blood where it functions to control vascular integrity and trafficking of lymphocytes. Obesity increases blood S1P levels in humans and mice. With the world wide increase in obesity linked to consumption of high-fat, high-sugar diets, S1P is emerging as an accomplice in liver pathobiology, including acute liver failure, metabolic syndrome, control of blood lipid and glucose homeostasis, nonalcoholic fatty liver disease, and liver fibrosis. Here, we review recent research on the importance of sphingosine kinases, S1P, and S1PRs in liver pathobiology, with a focus on exciting insights for new therapeutic modalities that target S1P signaling axes for a variety of liver diseases.

The anti-inflammatory effects of Morin hydrate in atherosclerosis is associated with autophagy induction through cAMP signaling

SCOPE

Although the previous trials of inflammation have indicated that morin hydrate (MO) hold considerable promise, understanding the distinct mechanism of MO against inflammation remains a challenge.

METHODS AND RESULTS

This study investigated the effect of MO in atherosclerosis in ApoE^-/- mice and underlying cell signaling of MO effect in inflammation in human umbilical vein endothelial cells (HUVECs). Administration of MO significantly reduced serum lipid level, inflammatory cytokines (TNF-α and ICAM-1), and atherosclerotic plaque formation in vivo. MO presence attenuated the expression of TNF-α-induced inflammatory cytokines (ICAM-1, COX-2, and MMP-9), and remarkably enhanced microtubule associated protein 1 light chain 3 beta 2 (MAP1LC3B2) expression and sequestosome 1 (SQSTM1/p62) degradation in HUVECs. These MO effects were significantly prevented by the presence of autophagic inhibitors, 3-methyladenine (3-MA), or chloroquine (CQ), as well as siRNA suppression of ATG5 and BECN1. MO increased intracellular cAMP levels and activated cAMP-PKA-AMPK-SIRT1 signaling in vivo and in vitro. These changes resulted in increased expression of autophagy-related protein MAP1LC3B2 and decreased secretion of inflammatory cytokines (ICAM-1, COX-2, and MMP-9).

CONCLUSION

Our results suggest that anti-AS and anti-inflammatory effects of MO are largely associated with its induction of autophagy through stimulation of cAMP-PKA-AMPK-SIRT1 signaling pathway.

Dietary Sugars and Endogenous Formation of Advanced Glycation Endproducts: Emerging Mechanisms of Disease

The rapid increase in metabolic diseases, which occurred in the last three decades in both industrialized and developing countries, has been related to the rise in sugar-added foods and sweetened beverages consumption. An emerging topic in the pathogenesis of metabolic diseases related to modern nutrition is the role of Advanced Glycation Endproducts (AGEs). AGEs can be ingested with high temperature processed foods, but also endogenously formed as a consequence of a high dietary sugar intake. Animal models of high sugar consumption, in particular fructose, have reported AGE accumulation in different tissues in association with peripheral insulin resistance and lipid metabolism alterations. The in vitro observation that fructose is one of the most rapid and effective glycating agents when compared to other sugars has prompted the investigation of the in vivo fructose-induced glycation. In particular, the widespread employment of fructose as sweetener has been ascribed by many experimental and observational studies for the enhancement of lipogenesis and intracellular lipid deposition. Indeed, diet-derived AGEs have been demonstrated to interfere with many cell functions such as lipid synthesis, inflammation, antioxidant defences, and mitochondrial metabolism. Moreover, emerging evidence also in humans suggest that this impact of dietary AGEs on different signalling pathways can contribute to the onset of organ damage in liver, skeletal and cardiac muscle, and the brain, affecting not only metabolic control, but global health. Indeed, the most recent reports on the effects of high sugar consumption and diet-derived AGEs on human health reviewed here suggest the need to limit the dietary sources of AGEs, including added sugars, to prevent the development of metabolic diseases and related comorbidities.

High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions

High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2) and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG), free fatty acid (FFA), uric acid (UA) and methylglyoxal (MG). Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption.