Wogonin mitigates nonalcoholic fatty liver disease via enhancing PPARα/AdipoR2, in vivo and in vitro

Analyzing the molecular mechanism of Scutellaria Radix in the treatment of sepsis using RNA sequencing

BACKGROUND

Sepsis is a life-threatening organ dysfunction, which seriously threatens human health. The clinical and experimental results have confirmed that Traditional Chinese medicine (TCM), such as Scutellariae Radix, has anti-inflammatory effects. This provides a new idea for the treatment of sepsis. This study systematically analyzed the mechanism of Scutellariae Radix treatment in sepsis based on network pharmacology, RNA sequencing and molecular docking.

METHODS

Gene expression analysis was performed using Bulk RNA sequencing on sepsis patients and healthy volunteers. After quality control of the results, the differentially expressed genes (DEGs) were analyzed. The active ingredients and targets of Scutellariae Radix were identified using The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Gene Ontology (GO) and Protein-Protein Interaction (PPI) analysis were performed for disease-drug intersection targets. With the help of GEO database, Survival analysis and Meta-analysis was performed on the cross-targets to evaluate the prognostic value and screen the core targets. Subsequently, single-cell RNA sequencing was used to determine where the core targets are located within the cell. Finally, in this study, molecular docking experiments were performed to further clarify the interrelationship between the active components of Scutellariae Radix and the corresponding targets.

RESULTS

There were 72 active ingredients of Scutellariae Radix, and 50 common targets of drug and disease. GO and PPI analysis showed that the intersection targets were mainly involved in response to chemical stress, response to oxygen levels, response to drug, regulation of immune system process. Survival analysis showed that PRKCD, EGLN1 and CFLAR were positively correlated with sepsis prognosis. Meta-analysis found that the three genes were highly expressed in sepsis survivor, while lowly in non-survivor. PRKCD was mostly found in Macrophages, while EGLN1 and CFLAR were widely expressed in immune cells. The active ingredient Apigenin regulates CFLAR expression, Baicalein regulates EGLN1 expression, and Wogonin regulates PRKCD expression. Molecular docking studies confrmed that the three active components of astragalus have good binding activities with their corresponding targets.

CONCLUSIONS

Apigenin, Baicalein and Wogonin, important active components of Scutellaria Radix, produce anti-sepsis effects by regulating the expression of their targets CFLAR, EGLN1 and PRKCD.

An optimal combination of four active components in Huangqin decoction for the synergistic sensitization of irinotecan against colorectal cancer

BACKGROUND

Irinotecan (CPT-11) is a first-line treatment for advanced colorectal cancer (CRC). Four components (baicalin, baicalein, wogonin, and glycyrrhizic acid) derived from Huangqin Decoction (HQD) have been proven to enhance the anticancer activity of CPT-11 in our previous study.

OBJECTIVE

This study aimed to determine the optimal combination of the four components for sensitizing CPT-11 as well as to explore the underlying mechanism.

METHODS

The orthogonal design method was applied to obtain candidate combinations (Cmb1-9) of the four components. The influence of different combinations on the anticancer effect of CPT-11 was first evaluated in vitro by cell viability, wound healing ability, cloning formation, apoptosis, and cell cycle arrest. Then, a CRC xenograft mice model was constructed to evaluate the anticancer effect of the optimal combination in vivo. Potential mechanisms of the optimal combination exerting a sensitization effect combined with CPT-11 against CRC were analyzed by targeted metabolomics.

RESULTS

In vitro experiments determined that Cmb8 comprised of baicalin, baicalein, wogonin, and glycyrrhizic acid at the concentrations of 17 μM, 47 μM, 46.5 μM and 9.8 μM respectively was the most effective combination. Importantly, the cell viability assay showed that Cmb8 exhibited synergistic anticancer activity in combination with CPT-11. In in vivo experiments, this combination (15 mg/kg of baicalin, 24 mg/kg of baicalein, 24 mg/kg of wogonin, and 15 mg/kg of glycyrrhizic acid) also showed a synergistic anticancer effect. Meanwhile, inflammatory factors and pathological examination of the colon showed that Cmb8 could alleviate the gastrointestinal damage induced by CPT-11. Metabolic profiling of the tumors suggested that the synergistic anticancer effect of Cmb8 might be related to the regulation of fatty acid metabolism.

CONCLUSION

The optimal combination of four components derived from HQD for the synergistic sensitization of CPT-11 against CRC was identified.

Wogonin Alleviates DCD Liver Ischemia/Reperfusion Injury by Regulating ALOX15/iNOS-mediated Ferroptosis

BACKGROUND

Donation after circulatory death livers are more susceptible to ischemia/reperfusion injury (IRI) because of a longer period of warm ischemia. Growing evidence now suggests that ferroptosis plays a key regulatory role in the development of IRI, so targeting ferroptosis may be an effective strategy to alleviate IRI in liver transplantation (LT).

METHODS

Using donation after circulatory death LT models in rats and oxygen-glucose deprivation/reoxygenation (OGD/R) models in BRL-3A cells, we tested the effect of the Chinese medicine monomer wogonin on liver IRI and explored the specific mechanism.

RESULTS

Wogonin attenuated liver IRI and increased the survival rate of rats by inhibiting lipid peroxidation and ferroptosis. Mechanistically, arachidonic acid 15-lipoxygenase-1 (ALOX15) and inducible nitric oxide synthase (iNOS) were identified as potential targets of baicalein through bioinformatics analysis combined with in vivo and in vitro experiments. This result was further confirmed by molecular docking and cellular thermal shift assays. Finally, we silenced ALOX15 and iNOS in the OGD/R cell model and found that silencing ALOX15 and iNOS could reproduce the regulatory effect of wogonin and abrogate the regulatory effect of wogonin.

CONCLUSIONS

In brief, this study emphasizes that wogonin exerts a protective effect in liver IRI through the regulation of ALOX15- and iNOS-mediated ferroptosis. ALOX15 and iNOS are potential targets for intervention in IRI induced by LT, and wogonin is a drug candidate for LT patients.

Osmanthus fragrans Flavonoid Extract Inhibits Adipogenesis and Induces Beiging in 3T3-L1 Adipocytes

Osmanthus fragrans has a long history of cultivation in Asia and is widely used in food production for its unique aroma, which has important cultural and economic values. It is rich in flavonoids with diverse pharmacological properties, such as antioxidant, anti-tumor, and anti-lipid activities. However, little is known regarding the effects of Osmanthus fragrans flavonoid extract (OFFE) on adipogenesis and pre-adipocyte transdifferentiation. Herein, this research aimed to investigate the effect of OFFE on the differentiation, adipogenesis, and beiging of 3T3-L1 adipocytes and to elucidate the underlying mechanism. Results showed that OFFE inhibited adipogenesis, reduced intracellular reactive oxygen species levels in mature adipocytes, and promoted mitochondrial biogenesis as well as beiging/browning in 3T3-L1 adipocytes. This effect was accompanied by increased mRNA and protein levels of the brown adipose-specific marker gene Pgc-1a, and the upregulation of the expression of UCP1, Cox7A1, and Cox8B. Moreover, the research observed a dose-dependent reduction in the mRNA expression of adipogenic genes (C/EBPα, GLUT-4, SREBP-1C, and FASN) with increasing concentrations of OFFE. Additionally, OFFE activated the AMPK signaling pathway to inhibit adipogenesis. These findings elucidate that OFFE has an inhibitory effect on adipogenesis and promotes browning in 3T3-L1 adipocytes, which lays the foundation for further investigation of the lipid-lowering mechanism of OFFE in vivo in the future.

Chaihu Guizhi Ganjiang Decoction attenuates nonalcoholic steatohepatitis by enhancing intestinal barrier integrity and ameliorating PPARα mediated lipotoxicity

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is a prominent cause of liver-related death that poses a threat to global health and is characterized by severe hepatic steatosis, lobular inflammation, and ballooning degeneration. To date, no Food and Drug Administration-approved medicine is commercially available. The Chaihu Guizhi Ganjiang Decoction (CGGD) shows potential curative effects on regulation of blood lipids and blood glucose, mitigation of organism inflammation, and amelioration of hepatic function. However, the overall regulatory mechanisms underlying its effects on NASH remain unclear.

PURPOSE

This study aimed to investigate the efficiency of CGGD on methionine- and choline-deficient (MCD)-induced NASH and unravel its underlying mechanisms.

METHODS

A NASH model of SD rats was established using an MCD diet for 8 weeks, and the efficacy of CGGD was evaluated based on hepatic lipid accumulation, inflammatory response, and fibrosis. The effects of CGGD on the intestinal barrier, metabolic profile, and differentially expressed genes (DEGs) profile were analyzed by integrating gut microbiota, metabolomics, and transcriptome sequencing to elucidate its mechanisms of action.

RESULTS

In MCD-induced NASH rats, pathological staining demonstrated that CGGD alleviated lipid accumulation, inflammatory cell infiltration, and fibrosis in the hepatic tissue. After CGGD administration, liver index, liver weight, serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) contents, liver triglycerides (TG), and free fatty acids (FFAs) were decreased, meanwhile, it down-regulated the level of proinflammatory mediators (TNF-α, IL-6, IL-1β, MCP-1), and up-regulated the level of anti-inflammatory factors (IL-4, IL-10), and the expression of liver fibrosis markers TGFβ, Acta2, Col1a1 and Col1a2 were weakened. Mechanistically, CGGD treatment altered the diversity of intestinal flora, as evidenced by the depletion of Allobaculum, Blautia, norank_f_Erysipelotrichaceae, and enrichment of the probiotic genera Roseburia, Lactobacillus, Lachnoclostridium, etc. The colonic histopathological results indicated that the gut barrier damage recovered in the CGGD treatment group, and the expression levels of colonic short-chain fatty acids (SCFAs)-specific receptors FFAR2, FFAR3, and tight junction (TJs) proteins ZO-1, Occludin, Claudin-1 were increased compared with those in the model group. Further metabolomic and transcriptomic analyses suggested that CGGD mitigated the lipotoxicity caused by glycerophospholipid and eicosanoid metabolism disorders by decreasing the levels of PLA2G4A, LPCAT1, COX2, and LOX5. In addition, CGGD could activate the inhibitory lipotoxic transcription factor PPARα, regulate the proteins of FABP1, APOC2, APOA2, and LPL to promote fatty acid catabolism, and suppress the TLR4/MyD88/NFκB pathway to attenuate NASH.

CONCLUSION

Our study demonstrated that CGGD improved steatosis, inflammation, and fibrosis on NASH through enhancing intestinal barrier integrity and alleviating PPARα mediated lipotoxicity, which makes it an attractive candidate for potential new strategies for NASH prevention and treatment.

Didymin alleviates metabolic dysfunction-associated fatty liver disease (MAFLD) via the stimulation of Sirt1-mediated lipophagy and mitochondrial biogenesis

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is one of the most prevalent metabolic syndromes worldwide. However, no approved pharmacological treatments are available for MAFLD. Chenpi, one kind of dried peel of citrus fruits, has traditionally been utilized as a medicinal herb for liver diseases. Didymin is a newly identified oral bioactive dietary flavonoid glycoside derived from Chenpi. In this study, we investigated the therapeutic potential of Didymin as an anti-MAFLD drug and elucidated its underlying mechanisms.

METHODS

High-fat diet (HFD)-induced MAFLD mice and alpha mouse liver 12 (AML12) cells were utilized to evaluate the effects and mechanisms of Didymin in the treatment of MAFLD. Liver weight, serum biochemical parameters, and liver morphology were examined to demonstrate the therapeutic efficacy of Didymin in MAFLD treatment. RNA-seq analysis was performed to identify potential pathways that could be affected by Didymin. The impact of Didymin on Sirt1 was corroborated through western blot, molecular docking analysis, microscale thermophoresis (MST), and deacetylase activity assay. Then, a Sirt1 inhibitor (EX-527) was utilized to confirm that Didymin alleviates MAFLD via Sirt1. Western blot and additional assays were used to investigate the underlying mechanisms.

RESULTS

Our results suggested that Didymin may possess therapeutic potential against MAFLD in vitro and in vivo. By promoting Sirt1 expression as well as directly binding to and activating Sirt1, Didymin triggers downstream pathways that enhance mitochondrial biogenesis and function while reducing apoptosis and enhancing lipophagy.

CONCLUSIONS

These suggest that Didymin could be a promising medication for MAFLD treatment. Furthermore, its therapeutic effects are mediated by Sirt1.

Dendrobium mixture ameliorates hepatic injury induced by insulin resistance in vitro and in vivo through the downregulation of AGE/RAGE/Akt signaling pathway

Dendrobium mixture (DM) is a patented Chinese herbal medicine which has been shown to ameliorate type 2 diabetes mellitus (T2DM) with non-alcoholic fatty liver disease (NAFLD) in vivo and in vitro. We aimed to investigate the underlying mechanism of DM as a therapeutic agent in attenuating liver steatosis in relation to type 2 diabetes mellitus (T2DM). DM (16.2 g/kg/d) was administered to db/db mice for 4 weeks. The db/m mice and db/db mice in the control and model groups were given normal saline. Additionally, DM (11.25 g/kg/d) was administered to Sprague-Dawley (SD) rats, and the serum was collected and used in an experiment involving palmitic acid (PA)-induced human liver HepG2 cells with abnormal lipid and glucose metabolism. In db/db mice, the administration of DM significantly alleviated liver steatosis, including histological damage and cell apoptosis. DM was found to prevent the upregulation of the RAGE and AKT1 proteins in liver tissues. The underlying mechanism of DM was further studied in PA-induced HepG2 cells. Post-DM administration serum from SD rats reduced lipid accumulation and regulated glucose metabolism in HepG2 cells. Consequently, it inhibited RAGE/AKT signaling and restored autophagy activity. The upregulated autophagy was associated with the mTOR-AMPK signaling pathway. Furthermore, post-DM administration serum reduced apoptosis of hepatocytes in PA-induced HepG2 cells. Our study supports the potential use of DM as a therapeutic agent for the treatment of NAFLD in T2DM. The mechanism underlying this therapeutic potential is associated with the downregulation of the AGE/RAGE/Akt signaling pathway.

Preventive and therapeutic effects of natural products and herbal extracts on nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a common condition that is prevalent in patients who consume little or no alcohol, and is characterized by excessive fat accumulation in the liver. The disease is becoming increasingly common with the rapid economic development of countries. Long-term accumulation of excess fat can lead to NAFLD, which represents a global health problem with no effective therapeutic approach. NAFLD is a complex, multifaceted pathological process that has been the subject of extensive research over the past few decades. Herbal medicines have gained attention as potential therapeutic agents to prevent and treat NAFLD due to their high efficacy and low risk of side effects. Our overview is based on a PubMed and Web of Science database search as of Dec 22 with the keywords: NAFLD/NASH Natural products and NAFLD/NASH Herbal extract. In this review, we evaluate the use of herbal medicines in the treatment of NAFLD. These natural resources have the potential to inform innovative drug research and the development of treatments for NAFLD in the future.

Integrated serum pharmacochemistry, 16S rRNA sequencing and metabolomics to reveal the material basis and mechanism of Yinzhihuang granule against non-alcoholic fatty liver disease

ETHNOPHARMACOLOGICAL RELEVANCE

Yinzhihuang granule (YZHG) has liver protective effect and can be used for clinical treatment of non-alcoholic fatty liver disease (NAFLD), but its material basis and mechanism need to be further clarified.

AIM OF THE STUDY

This study aims to reveal the material basis and mechanism of YZHG treating NAFLD.

MATERIALS AND METHODS

Serum pharmacochemistry were employed to identify the components from YZHG. The potential targets of YZHG against NAFLD were predicted by system biology and then preliminarily verified by molecular docking. Furthermore, the functional mechanism of YZHG in NAFLD mice was elucidated by 16S rRNA sequencing and untargeted metabolomics.

RESULTS

From YZHG, 52 compounds were identified, of which 42 were absorbed into the blood. Network pharmacology and molecular docking showed that YZHG treats NAFLD with multi-components and multi-targets. YZHG can improve the levels of blood lipids, liver enzymes, lipopolysaccharide (LPS), and inflammatory factors in NAFLD mice. YZHG can also significantly improve the diversity and richness of intestinal flora and regulate glycerophospholipid and sphingolipid metabolism. Moreover, Western Blot experiment showed that YZHG can regulate liver lipid metabolism and enhance intestinal barrier function.

CONCLUSIONS

YZHG may treat NAFLD by improving the disruption of intestinal flora and enhancing the intestinal barrier. This will reduce the invasion of LPS into the liver subsequently regulate liver lipid metabolism and reduce liver inflammation.

Dendrobium mixture ameliorates type 2 diabetes mellitus with non-alcoholic fatty liver disease through PPAR gamma: An integrated study of bioinformatics analysis and experimental verification

Dendrobium mixture (DM) is a patented Chinese herbal medicine indicated which has anti-inflammatory and improved glycolipid metabolism. However, its active ingredients, targets of action, and potential mechanisms are still uncertain. Here, we investigate the role of DM as a prospective modulator of protection against non-alcoholic fatty liver disease (NAFLD) induced by type 2 diabetes mellitus (T2DM) and illustrate the molecular mechanisms potentially involved. The network pharmacology and TMT-based quantitative protomics analysis were conducted to identify potential gene targets of the active ingredients in DM against NAFLD and T2DM. DM was administered to the mice of DM group for 4 weeks, and db/m mice (control group) and db/db mice (model group) were gavaged by normal saline. DM was also given to Sprague-Dawley (SD) rats, and the serum was subjected to the palmitic acid-induced HepG2 cells with abnormal lipid metabolism. The mechanism of DM protection against T2DM-NAFLD is to improve liver function and pathological morphology by promoting peroxisome proliferator-activated receptor γ (PPARγ) activation, lowering blood glucose, improving insulin resistance (IR), and reducing inflammatory factors. In db/db mice, DM reduced RBG, body weight, and serum lipids levels, and significantly alleviated histological damage of liver steatosis and inflammation. It upregulated the PPARγ corresponding to the prediction from the bioinformatics analysis. DM significantly reduced inflammation by activating PPARγ in both db/db mice and palmitic acid-induced HepG2 cells.

Wogonin, a Compound in Scutellaria baicalensis, Activates ATF4–FGF21 Signaling in Mouse Hepatocyte AML12 Cells

Fibroblast growth factor 21 (FGF21), which is mainly synthesized and secreted by the liver, plays a crucial role in systemic glucose and lipid metabolism, ameliorating metabolic diseases. In this study, we screened the WAKANYAKU library derived from medicinal herbs to identify compounds that can activate Fgf21 expression in mouse hepatocyte AML12 cells. We identified Scutellaria baicalensis root extract and one of its components, wogonin, as an activator of Fgf21 expression. Wogonin also enhanced the expression of activating transcription factor 4 (ATF4) by a mechanism other than ER stress. Knockdown of ATF4 by siRNA suppressed wogonin-induced Fgf21 expression, highlighting its essential role in wogonin’s mode of action. Thus, our results indicate that wogonin would be a strong candidate for a therapeutic to improve metabolic diseases by enhancing hepatic FGF21 production.

Natural PPARs agonists for the treatment of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a general term for a series of liver diseases including simple steatosis, non-alcoholic steatohepatitis, liver fibrosis, which is closely related to metabolic syndrome. The pathogenesis of NAFLD is relatively complex, which has gradually changed from the previous 'two-hit' hypothesis to the current "multiple hits" hypothesis. However, there is currently no approved treatment for NAFLD in clinic, highlighting the urgent need for drug development. Peroxisome proliferator activated receptors (PPARs) are members of the nuclear receptor superfamily, whose different subtypes have been proved to regulate different stages of NAFLD, thus becoming promising drug targets for NAFLD. As important sources of drug development, natural products have been proven to treat NAFLD through multiple pathways and multiple targets. In this paper, we outline the regulatory role of PPARs in NAFLD, and summarize some natural products that target PPARs to ameliorate NAFLD, in order to provide reference for drug development of NAFLD.

PPAR-α Agonist GW7647 Protects Against Oxidative Stress and Iron Deposit via GPx4 in a Transgenic Mouse Model of Alzheimer's Diseases

Alzheimer's disease (AD) is a neurodegenerative disease caused by lipid peroxidation and iron hemostasis of the brain. PPAR-α is regarded as the most encouraging therapeutic approach of several neurodegenerative and metabolic disorders, due to its potent regulatory effects. In this study, we examined the ameliorative effect and the mechanisms of a PPAR-α agonist, GW7647, on the established AD models using APP/PS1 mice and APPsw/SH-SY5Y cells. Through Aβ quantification and behavioral test, we found that GW7647 reduced Aβ burden and improved cognitive defect in APP/PS1 mice. Liquid chromatography-mass spectrometry analysis indicated that GW7647 could enter the brain after oral administration. Neuronal cell death and iron deposit were inhibited, accompanied by decreased lipid peroxidation and inflammation. In an in vitro study of APPsw cells, we found that PPAR-α directly bound with GPx4 intron3 to promote GPx4 transcription and reduced the iron transport capability. Our data suggested that activation of PPAR-α by GW7647 improved the disruption of iron homeostasis in the brain of APP/PS1 mice and alleviated neuronal inflammation and lipid peroxidation, which was possibly related to the upregulated transcription of GPx4 mediated by the interaction of GPx4 noncoding region and the PPAR-α.

Traditional Chinese Medicine in nonalcoholic fatty liver disease: molecular insights and therapeutic perspectives

Nonalcoholic fatty liver disease (NAFLD) has become the world's largest chronic liver disease, while there is still no specific drug to treat NAFLD. Traditional Chinese Medicine (TCM) have been widely used in hepatic diseases for centuries in Asia, and TCM's holistic concept and differentiation treatment of NAFLD show their advantages in the treatment of this complex metabolic disease. However, the multi-compounds and multi-targets are big obstacle for the study of TCM. Here, we summarize the pharmacological actions of active ingredients from frequently used single herbs in TCM compounds. The combined mechanism of herbs in TCM compounds are further discussed to explore their comprehensive effects on NAFLD. This article aims to summarize multiple functions and find the common ground for TCM treatment on NAFLD, thus providing enrichment to the scientific connotation of TCM theories and promotes the exploration of TCM therapies on NAFLD.

Wogonin alleviates liver injury in sepsis through Nrf2-mediated NF-κB signalling suppression

Sepsis is a life‐threatening organ dysfunction syndrome, and liver is a susceptible target organ in sepsis, because the activation of inflammatory pathways contributes to septic liver injury. Oxidative stress has been documented to participate in septic liver injury, because it not only directly induces oxidative genotoxicity, but also exacerbates inflammatory pathways to potentiate damage of liver. Therefore, to ameliorate oxidative stress is promising for protecting liver in sepsis. Wogonin is the compound extracted from the medicinal plant Scutellaria baicalensis Geogi and was found to exert therapeutic effects in multiple inflammatory diseases via alleviation of oxidative stress. However, whether wogonin is able to mitigate septic liver injury remains unknown. Herein, we firstly proved that wogonin treatment could improve survival of mice with lipopolysaccharide (LPS)‐ or caecal ligation and puncture (CLP)‐induced sepsis, together with restoration of reduced body temperature and respiratory rate, and suppression of several pro‐inflammatory cytokines in circulation. Then, we found that wogonin effectively alleviated liver injury via potentiation of the anti‐oxidative capacity. To be specific, wogonin activated Nrf2 thereby promoting expressions of anti‐oxidative enzymes including NQO‐1, GST, HO‐1, SOD1 and SOD2 in hepatocytes. Moreover, wogonin‐induced Nrf2 activation could suppress NF‐κB‐regulated up‐regulation of pro‐inflammatory cytokines. Ultimately, we provided in vivo evidence that wogonin activated Nrf2 signalling, potentiated anti‐oxidative enzymes and inhibited NF‐κB‐regulated pro‐inflammatory signalling. Taken together, this study demonstrates that wogonin can be the potential therapeutic agent for alleviating liver injury in sepsis by simultaneously ameliorating oxidative stress and inflammatory response through the activation of Nrf2.

Hesperetin ameliorates hepatic oxidative stress and inflammation via the PI3K/AKT-Nrf2-ARE pathway in oleic acid-induced HepG2 cells and a rat model of high-fat diet-induced NAFLD

Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disease. Dietary supplementation has become a promising strategy for managing NAFLD. Hesperetin, a citrus flavonoid, is mainly found in citrus fruits (oranges, grapefruit, and lemons) and possesses multiple pharmacological properties, including anti-cancer, anti-Alzheimer and anti-diabetic effects. However, the anti-NAFLD effect and mechanisms of hesperetin remain unclear. In this study, we investigated the therapeutic effect of hesperetin against NAFLD and the underlying mechanism in vitro and in vivo. In oleic acid (OA)-induced HepG2 cells, hesperetin upregulated antioxidant levels (SOD/GPx/GR/GCLC/HO-1) by triggering the PI3 K/AKT-Nrf2 pathway, alleviating OA-induced reactive oxygen species (ROS) overproduction and hepatotoxicity. Furthermore, hesperetin suppressed NF-κB activation and reduced inflammatory cytokine secretion (TNF-α and IL-6). More importantly, we revealed that this anti-inflammatory effect is attributed to reduced ROS overproduction by the Nrf2 pathway, as pre-treatment with Nrf2 siRNA or an inhibitor of superoxide dismutase (SOD) or/and glutathione peroxidase (GPx) abolished hesperetin-induced NF-κB inactivation and reductions in inflammatory cytokine secretion. In a rat model of high-fat diet (HFD)-induced NAFLD, we confirmed that hesperetin relieved hepatic steatosis, oxidative stress, inflammatory cell infiltration and fibrosis. Moreover, hesperetin activated the PI3 K/AKT-Nrf2 pathway in the liver, increasing antioxidant expression and inhibiting NF-κB activation and inflammatory cytokine secretion. In summary, our results demonstrate that hesperetin ameliorates hepatic oxidative stress through the PI3 K/AKT-Nrf2 pathway and that this antioxidative effect further suppresses NF-κB-mediated inflammation during NAFLD progression. Thus, our study suggests that hesperetin may be an effective dietary supplement for improving NAFLD by suppressing hepatic oxidative stress and inflammation.

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.

Identification of potential bioactive compounds and mechanisms of GegenQinlian decoction on improving insulin resistance in adipose, liver, and muscle tissue by integrating system pharmacology and bioinformatics analysis

ETHNOPHARMACOLOGICAL RELEVANCE

GegenQinlian Decoction (GQD), a classical formula in traditional Chinese medicine, is widely used in the treatment of diabetes. While studies have demonstrated that GQD is an efficacious treatment for insulin resistance (IR) in type 2 diabetes mellitus (T2DM), the potential bioactive compounds and mechanisms remain unclear.

AIM OF THE STUDY

To further investigate the potential bioactive compounds, targets, and pathways of GQD on improving IR in T2DM for adipose, liver, and muscle tissue using an integrated strategy of system pharmacology and bioinformatics analysis.

MATERIALS AND METHODS

We screened the candidate compounds and targets of GQD and identified IR-associated differentially expressed genes (DEGs) of adipose, liver, and muscle tissue, respectively. Then the intersecting target genes between candidate targets and DEGs were used for "GQD-compounds-targets-tissue" network construction in each type of tissue. The top 10 bioactive compounds acting on each type of tissue were intersected and consequently identified as potential bioactive compounds of GQD. Furthermore, pathway enrichment, protein-protein interaction (PPI) network construction, and hub target identification were performed based on the targets of GQD and the targets of quercetin in each type of tissue, respectively. Finally, to further confirm the role of quercetin, we intersected the hub targets of quercetin and the hub targets of GQD, and the pathways were intersected as well.

RESULTS

132 compounds and 119 potential targets of these compounds were obtained. 1,765, 3,206, and 3594 DEGs were identified between IR and insulin sensitivity (IS) tissue in adipose, liver, and muscle, respectively. There were 21, 23, 45 targets and 103, 73, 123 compounds in the "GQD-compounds-targets-tissue" network of adipose, liver, and muscle tissue, respectively. Then compounds such as quercetin, kaempferol, baicalein, wogonin, isorhamnetin, beta-sitosterol and licochalcone A, were identified as the potential bioactive compounds of GQD, and quercetin had the highest degree among the compounds. Moreover, based on the targets of GQD, hub targets like PPARG, RELA, EGFR, CASP3, VEGFA, AR, ESR1 and CCND1, and signaling pathways such as insulin signaling pathway, endocrine resistance, TNF signaling pathway, PI3K-Akt signaling pathway, AMPK signaling pathway, MAPK signaling pathway, NF-κB signaling pathway, HIF-1 signaling pathway, apoptosis, and VEGF signaling pathway, were filtered out as the underlying mechanisms of GQD on improving diabetic IR. In addition, the hub targets and pathways of quercetin coincided with most of the hub targets and pathways of GQD in each type of tissue, respectively, suggesting that quercetin may be a potential representative compound of GQD.

CONCLUSIONS

Our analysis identifies the potential bioactive compounds, targets, and pathways of GQD on improving IR in T2DM for adipose, liver, and muscle tissue, which shows the characteristics of multi-compounds, multi-targets, multi-pathways, and multi-mechanisms of GQD and lays a solid foundation for further experimental research and clinical application.

Honokiol Alleviates Methionine-Choline Deficient Diet-Induced Hepatic Steatosis and Oxidative Stress in C57BL/6 Mice by Regulating CFLAR-JNK Pathway

Background

Honokiol (HNK) has been reported to possess various beneficial effects in the context of metabolic disorders, including fatty liver, insulin resistance, and oxidative stress which are closely related to nonalcoholic steatohepatitis (NASH), however with no particular reference to CFLAR or JNK.

Methods

C57BL/6 mice were fed methionine-choline-deficient (MCD) diet and administered simultaneously with HNK (10 and 20 mg/kg once a day, ig) for 6 weeks, and NCTC1469 cells were pretreated, respectively, by oleic acid (OA, 0.5 mmol/L) plus palmitic acid (PA, 0.25 mmol/L) for 24 h, and adenovirus-down Cflar for 24 h, then exposed to HNK (10 and 20 μmol/L) for 24 h. Commercial kits, H&E, MT, ORO staining, RT-qPCR, and Western blotting were used to detect the biomarkers, hepatic histological changes, and the expression of key genes involved in NASH.

Results

The in vivo results showed that HNK suppressed the phosphorylation of JNK (pJNK) by activating CFLAR; enhanced the mRNA expression of lipid metabolism-related genes Acox, Cpt1α, Fabp5, Gpat, Mttp, Pparα, and Scd-1; and decreased the levels of hepatic TG, TC, and MDA, as well as the levels of serum ALT and AST. Additionally, HNK enhanced the protein expression of oxidative stress-related key regulatory gene NRF2 and the activities of antioxidases HO-1, CAT, and GSH-Px and decreased the protein levels of prooxidases CYP4A and CYP2E1. The in vivo effects of HNK on the expression of CLFAR, pJNK, and NRF2 were proved by the in vitro experiments. Moreover, HNK promoted the phosphorylation of IRS1 (pIRS1) in both tested cells and increased the uptake of fluorescent glucose 2-NBDG in OA- and PA-pretreated cells.

Conclusions

HNK ameliorated NASH mainly by activating the CFLAR-JNK pathway, which not only alleviated fat deposition by promoting the efflux and β-oxidation of fatty acids in the liver but also attenuated hepatic oxidative damage and insulin resistance by upregulating the expression of NRF2 and pIRS1.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

Study on the Mechanism of Shugan Xiaozhi Fang on Cells with Non-alcoholic Fatty Liver Disease

Cells with non-alcoholic fatty liver disease (NAFLD) were studied to determine the mechanism of liver deficiency via the AdipoR2-PPARa pathway. NAFLD cells were randomly divided into a normal control group, blank control group, model group, low dose group, medium dose group, and high dose group. The NAFLD models were established by incubating the cells with linoleic acid (LA) and palmitic acid (PA) (2:1) for 24 h. The test groups were incubated with different doses of Shugan Xiaozhi Fang extract. The pathological changes in cells that accumulated lipids were detected by Oil Red O staining. Malondialdehyde (MDA) and triglyceride (TG) levels were measured. The apoptosis of cells was evaluated by flow cytometry. The levels of AdipoR2, PPARa, CD36, acyl-CoA mRNA, and protein were confirmed by RT- PCR and Western blot. The results of the Oil Red O staining demonstrated that the NAFLD cell model was successfully established. Compared with the model group, the levels of TG and MDA in the groups that received low, medium, and high doses of Shugan Xiaozhi were significantly lower (P<0.01), and a dose effect was evident. In addition, the expression of AdipoR2, PPARa, CD36, acyl-CoA protein, and mRNA in the Shugan Xiaozhi-treated groups was upregulated. Furthermore, the levels of AdipoR2, PPAR, CD36, acyl-CoA protein, and mRNA in all drug treatment groups that were extracted from L-O2 normal human hepatocytes were significantly upregulated (P<0.01). Moreover, the factor pattern of HepG2 human liver carcinoma cells was similar to that of L-O2. The levels of AdipoR, CD36, acyl-CoA, and AdipoR mRNA in the HepG2 low group were increased (P<0.05). AdipoR, PPAR, CD36, and acyl-CoA protein levels and AdipoR mRNA expression were significantly increased in the intermediate dose group and high dose group (P<0.01). Shugan Xiaozhi Fang attenuates hepatic lipid deposition in NAFLD induced by incubating with LA and PA for 24 h, which is associated with the activation of the AdipoR2-PPARα pathway.

Cardio protective role of wogonin loaded nanoparticle against isoproterenol induced myocardial infarction by moderating oxidative stress and inflammation

Wogonin, one of the main active ingredients of Scutellaria radix, is a kind of flavonoid compound. In the present study, we report that wogonin nanoparticles (Wog np) protect Isoproterenol (ISO) induced Myocardial Infarction (MI) rats. Nanoparticles of sizes less than 200 nm with spherical shape were prepared using Polylactic-co-glycolic acid (PLGA) and Polyvinyl alcohol (PVA) respectively as polymer and stabilizer. Male Wistar rats were divided into 4 groups. Group 1 as a control group administered with physiological saline solution with 0.5 % carboxymethylcellulose (1 mL/day). Group 2 served as toxic group; rats received physiological saline solution with 0.5 % carboxymethylcellulose (1 mL/day) orally for 21 days Groups 3 and 4 received Wog np (25 and 50 mg/kg/day) orally for 21 days and on the 20th and 21 st days group 2, 3, and 4 were administered with ISO (85 mg/kg) through s.c. route at 24 h interval. pre-treatment with Wog np (25 and 50 mg/kg) could significantly reduce the cardiac infarct size, serum cardiac markers, lipid peroxidation product (MDA) and inflammatory markers as well as markedly upregulated the protein expression of nuclear factor erythroid 2-related factor (Nrf2)and heme oxygenase-1 (HO-1) to confer its strong cardioprotective activity against ISO induced myocardial damage.

Silibinin ameliorates hepatic lipid accumulation and oxidative stress in mice with non-alcoholic steatohepatitis by regulating CFLAR-JNK pathway

Non-alcoholic steatohepatitis (NASH) is a chronic metabolic syndrome and the CFLAR-JNK pathway can reverse the process of NASH. Although silibinin is used for the treatment of NASH in clinical, its effect on CFLAR-JNK pathway in NASH remains unclear. This study aimed to investigate the effect of silibinin on CFLAR-JNK pathway in NASH models both in vivo and in vitro. The in vivo study was performed using male C57BL/6 mice fed with methionine- choline-deficient diet and simultaneously treated with silibinin for 6 weeks. The in vitro study was performed by using mouse NCTC-1469 cells which were respectively pretreated with oleic acid plus palmitic acid, and adenovirus-down Cflar for 24 h, then treated with silibinin for 24 h. After the drug treatment, the key indicators involved in CFLAR-JNK pathway including hepatic injury, lipid metabolism and oxidative stress were determined. Silibinin significantly activated CFLAR and inhibited the phosphorylation of JNK, up-regulated the mRNA expression of Pparα, Fabp5, Cpt1α, Acox, Scd-1, Gpat and Mttp, reduced the activities of serum ALT and AST and the contents of hepatic TG, TC and MDA, increased the expression of NRF2 and the activities of CAT, GSH-Px and HO-1, and decreased the activities and expression of CYP2E1 and CYP4A in vivo. These effects were confirmed by the in vitro experiments. Silibinin prevented NASH by regulating CFLAR-JNK pathway, and thereby on one hand promoting the β-oxidation and efflux of fatty acids in liver to relieve lipid accumulation, and on the other hand inducing antioxidase activity (CAT, GSH-Px and HO-1) and inhibiting pro-oxidase activity (CYP2E1 and CYP4A) to relieve oxidative stress.

Traditional Chinese medicine combined with hepatic targeted drug delivery systems: A new strategy for the treatment of liver diseases

Liver diseases are clinically common and present a substantial public health issue. Many of the currently available drugs for the treatment of liver diseases suffer from limitations that include low hepatic distribution, lack of target effects, poor in vivo stability and adverse effects on other organs. Consequently, conventional treatment of hepatic diseases is ineffective. TCM is commonly used in the treatment of liver diseases worldwide, particularly in China, and has advantages over conventional therapy. HTDDS can be designed to enhance clinical efficacy in the treatment of liver diseases. We have conducted an extensive review of 335 studies reported since 1964. These included about 166 references involving the treatment of liver diseases with TCM (covering active components of TCM, single TCM and Chinese medicine formulas), 169 reports on HTDDS and background studies on liver-related diseases. Here we review the long history of TCM in the treatment of liver diseases.We have also reviewed the status of studies on active components of TCM using nanotechnology-based targeted delivery systems to provide support for further research and development of TCM-based targeted preparations for the treatment of liver disease.

Synergistic Effect of Bupleuri Radix and Scutellariae Radix on Adipogenesis and AMP-Activated Protein Kinase: A Network Pharmacological Approach

Obesity has become a major health threat in developed countries. However, current medications for obesity are limited because of their adverse effects. Interest in natural products for the treatment of obesity is thus rapidly growing. Korean medicine is characterized by the wide use of herbal formulas. However, the combination rule of herbal formulas in Korean medicine lacks experimental evidence. According to Shennong's Classic of Materia Medica, the earliest book of herbal medicine, Bupleuri Radix (BR) and Scutellariae Radix (SR) possess the Sangsoo relationship, which means they have synergistic features when used together. Therefore these two are frequently used together in prescriptions such as Sosiho-Tang. In this study, we used the network pharmacological method to predict the interaction between these two herbs and then investigated the effects of BR, SR, and their combination on obesity in 3T3-L1 adipocytes. BR, SR, and BR-SR mixture significantly decreased lipid accumulation and the expressions of two major adipogenic factors, peroxisome proliferator-activated receptor-gamma (PPARγ) and CCAAT/enhancer-binding protein-alpha (C/EBPα), and their downstream genes, Adipoq, aP2, and Lipin1 in 3T3-L1 cells. In addition, the BR-SR mixture had synergistic effects compared with BR or SR on inhibition of adipogenic-gene expressions. BR and SR also inhibited the protein expressions of PPARγ and C/EBPα. Furthermore, the two extracts successfully activated AMP-activated protein kinase alpha (AMPK α), the key regulator of energy metabolism. When compared to those of BR or SR, the BR-SR mixture showed higher inhibition rates of PPARγ and C/EBPα, along with higher activation rate of AMPK. These results indicate a new potential antiobese pharmacotherapy and also provide scientific evidence supporting the usage of herbal combinations instead of mixtures in Korean medicine.

Mechanism in the existent difference in form of wogonin/wogonoside between plasma and intestine/liver in rats

Wogonin (WO) and its glucuronide, wogonoside (WG) exhibit various beneficial bioactivities that may have potential for the development of novel drugs. In this study, we determined their pharmacokinetic characteristics in rats after intragastric administration of WO and intraportal vein injection of WG. WG was the predominant form in the portal vein and body plasma, and in bile; WO was detected only in the small intestine and liver. WG is a substrate of the multidrug resistance-associated protein (MRP) 1, 2, 3, and 4, and organic anion-transporting polypeptide (OATP) 2B1 and OATP1B3. Metabolism studies indicated that WG formation and WO decrease had similar CL_int values in rat intestine S9 (RIS9) and rat liver microsome (RLM), and that the hydrolysis rate of WG in RIS9 and rat liver S9 (RLS9) was fast. Thus, WG could be excreted into the intestinal tract by MRP2, and transported into mesenteric blood by MRP1, 3, and 4. OATP2B1 and OATP1B3 mediated the hepatic uptake of WG and MRPs mediated WG efflux to the bile and circulation. The high transport capability of MRPs for WG and the fast hydrolysis in the small intestine and liver may be responsible for the presence of WO in these tissues.

OATPs, MRPs, UGTs and β-glucuronidase mediate the difference of exposure form of wogonin and wogonoside in plasma and tissues.