Hydroxysafflor yellow A suppresses liver fibrosis induced by carbon tetrachloride with high-fat diet by regulating PPAR-γ/p38 MAPK signaling

Plant-derived flavonoids are a potential source of drugs for the treatment of liver fibrosis

Liver fibrosis is a dynamic pathological process that can be triggered by any chronic liver injury. If left unaddressed, it will inevitably progress to the severe outcomes of liver cirrhosis or even hepatocellular carcinoma. In the past few years, the prevalence and fatality of hepatic fibrosis have been steadily rising on a global scale. As a result of its intricate pathogenesis, the quest for pharmacological interventions targeting liver fibrosis has remained a formidable challenge. Currently, no pharmaceuticals are exhibiting substantial clinical efficacy in the management of hepatic fibrosis. Hence, it is of utmost importance to expedite the development of novel therapeutics for the treatment of this condition. Various research studies have revealed the ability of different natural flavonoid compounds to alleviate or reverse hepatic fibrosis through a range of mechanisms, which are related to the regulation of liver inflammation, oxidative stress, synthesis and secretion of fibrosis-related factors, hepatic stellate cells activation, and proliferation, and extracellular matrix synthesis and degradation by these compounds. This review summarizes the progress of research on different sources of natural flavonoids with inhibitory effects on liver fibrosis over the last decades. The anti-fibrotic effects of natural flavonoids have been increasingly studied, making them a potential source of drugs for the treatment of liver fibrosis due to their good efficacy and biosafety.

Mitochondrial-mediated nuclear remodeling and macrophage polarizations: A key switch from liver fibrosis to HCC progression

Liver fibrosis is a significant health burden worldwide and has emerged as the leading cause of Hepatocellular carcinoma (HCC) incidence. Mitochondria are the dynamic organelles that regulate the differentiation, survival, and polarization of macrophages. Nuclear-DNA-associated proteins, micro-RNAs, as well as macrophage polarization are essential for maintaining intracellular and extra-cellular homeostasis in the liver parenchyma. Dysregulated mitochondrial coding genes (ETS complexes I, II, III, IV, and V), non-coding RNAs (mitomiRs), and nuclear alteration lead to the production of reactive oxygen species (ROS) and inflammation which are implicated in the transition of liver fibrosis into HCC. Recent findings indicated the protecting effect of E74-like factor 3/peroxisome proliferator-activated receptor-γ (Elf-3/PPAR-γ). HDAR-y inhibits the deacetylation of PPAR-y and maintains the PPAR-y pathway. Elf-3 plays a tumor suppressive role through epithelial-mesenchymal transition-related gene and zinc finger E-box binding homeobox 2 (ZEB-2) domain. Additionally, the development of HCC includes the PI3K/Akt/mTOR and transforming Growth Factor β (TGF-β) pathway that promotes the Epithelial-mesenchymal transition (EMT) through Smad/Snail/Slug signaling cascade. In contrast, the TLR2/NOX2/autophagy axis promotes M2 polarization in HCC. Thus, a thorough understanding of the mitochondrial and nuclear reciprocal relationship related to macrophage polarization could provide new research opportunities concerning diseases with a significant impact on liver parenchyma towards developing liver fibrosis or liver cancer. Moreover, this knowledge can be used to develop new therapeutic strategies to treat liver diseases.

Dietary regulation of peroxisome proliferator-activated receptors in metabolic syndrome

BACKGROUND

Peroxisome proliferator-activated receptors (PPARs) are a class of ligand-activated nuclear transcription factors, members of the type nuclear receptor superfamily, with three subtypes, namely PPARα, PPARβ/δ, and PPARγ, which play a key role in the metabolic syndrome. In the past decades, a large number of studies have shown that natural products can act by regulating metabolic pathways mediated by PPARs.

PURPOSE

This work summarizes the physiological importance and clinical significance of PPARs and reviews the experimental evidence that natural products mediate metabolic syndrome via PPARs.

METHODS

This study reviews relevant literature on clinical trials, epidemiology, animals, and cell cultures published in NCBI PubMed, Scopus, Web of Science, Google Scholar, and other databases from 2001 to October 2022. Search keywords were "natural product" OR "botanical" OR "phytochemical" AND "PPAR" as well as free text words.

RESULTS

The modulatory involvement of PPARs in the metabolic syndrome has been supported by prior research. It has been observed that many natural products can treat metabolic syndrome by altering PPARs. The majority of currently described natural compounds are mild PPAR-selective agonists with therapeutic effects that are equivalent to synthetic medicines but less harmful adverse effects.

CONCLUSION

PPAR agonists can be combined with natural products to treat and prevent metabolic syndrome. Further human investigations are required because it is unknown how natural products cause harm and how they might have negative impacts.

Fenpropathrin increases gliquidone absorption via causing damage to the integrity of intestinal barrier

Fenpropathrin is a commonly used pesticide, which was ingested by humans through diet and water. Gliquidone is a common hypoglycemic drug that diabetic patients need for long-term use. This study aimed to investigate the effects of long-term exposure to fenpropathrin on the intestinal barrier and intestinal absorption of the model drug gliquidone. The Ussing Chamber study had shown that fenpropathrin can increase the transport of gliquidone in an isolated intestinal model. In addition, the intestinal absorption of fluorescein was significantly increased in fenpropathrin-exposed rats administered by gavage. Further research suggested that fenpropathrin exposure caused a series of pathological effects: the structure of the intestine was damaged, the expression of tight junction proteins in the intestinal tissue was decreased, the intestinal MDA was increased, the SOD was decreased, and the expression of inflammatory factors was increased. In the Caco-2 cell model, it was found that fenpropathrin can increase the transport of gliquidone in the Caco-2 cell monolayer, reduce the expression of tight junction proteins and increase reactive oxygen species in Caco-2 cells. Fenpropathrin exposure also resulted in decreasing expression of PPAR-γ and UCP-2 in intestinal tissue and Caco-2 cell model, while causing increased expression of p-P38. The above results indicated that fenpropathrin exposure could induce oxidative stress and destroy the intestinal barrier by affecting the expression of p-P38/P38/PPAR-γ/UCP-2 protein, thereby increasing the intestinal absorption of gliquidone. This study provides new insights into the hazards of fenpropathrin residues in the environment.

Exploration of the Potential Targets and Molecular Mechanism of Carthamus tinctorius L. for Liver Fibrosis Based on Network Pharmacology and Molecular Docking Strategy

Carthamus tinctorius L. (Honghua, HH) is an herbal medicine and functional food widely used to treat chronic liver diseases, including liver fibrosis. By using network pharmacology and molecular docking experiments, the present study aims to determine the bioactive components, potential targets, and molecular mechanisms of HH for treating liver fibrosis. The components of HH were screened from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and literature, and the SwissTargetPrediction database was used to predict the treatment targets of HH. Genecards and DisGeNET databases contained targets for liver fibrosis, and the STRING database provided networks of protein–protein interactions. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using the Database of Annotation, Visualization and Integrated Discovery. The protein–protein interactive network and drug–component–major target–pathway interactive network were visualized and analyzed by Cytoscape software. Finally, Autodock Vina and Discovery Studio software were used for molecular docking Validation. A total of 23 candidate bioactive compounds with 187 treatment targets of HH were acquired from the databases and literature. A total of 121 overlapping targets between HH and liver fibrosis were found to provide the molecular basis for HH on liver fibrosis. Quercetin, beta carotene, and lignan were identified as key components with targeting to ESR1, PIK3CA, and MTOR. HH is engaged in the intervention of various signaling cascades associated with liver fibrosis, such as PI3K/AKT/mTOR pathway, MAPK pathway, and PPAR pathway. In conclusion, HH treats liver fibrosis through multi-component, multi-target, and multi-pathway mechanisms.

Evaluation of Toxicity, Bacteriostatic, Analgesic, Anti-Inflammatory, and Antipyretic Activities of Huangqin-Honghua-Pugongying-Jinyinhua Extract

The extensive use of antibiotics has caused the global spread of multidrug-resistant bacteria and genes, seriously reducing antibiotic efficacy and threatening animal and human health. As an alternative, traditional Chinese veterinary medicine (TCVM) was used in this study for its lack of drug resistance and low toxicity. Huangqin-honghua-pugongying-jinyinhua extract (HHPJE), a novel TCVM, consists of the extracts of Huangqin (Scutellaria baicalensis), Honghua (Carthami Flos), Pugongying (Taraxacum) and Jinyinhua (Lonicerae Japonicae Flos), and was developed to treat bovine mastitis. In this study, we evaluated the toxicity, bacteriostatic, analgesic, anti-inflammatory, and antipyretic activities of HHPJE. Our results show that HHPJE did not show any acute oral toxicity and can be considered safe for oral administration. Additionally, HHPJE possessed a dose-dependent antibacterial effect on Staphylococcus aureus, Escherichia coli, Streptococcus agalactiae and Streptococcus dysgalactiae. HHPJE (60, 30 and 15 g/kg) can reduce the abdominal pain by 44.83 ± 7.69%, 43.15 ± 9.50% and 26.14 ± 4.17%, respectively. The percentages of anti-inflammation inhibition (60, 30 and 15 g/kg) were 35.34 ± 2.17%, 22.29 ± 2.74% and 12.06 ± 3.61%, respectively. The inhibition rates (60, 30 and 15 g/kg) of antipyretic activity were 82.05%, 65.71% and 52.80%, respectively. The evaluation of pharmacodynamics and toxicity indicate that HHPJE possesses significant bacteriostatic, analgesic, anti-inflammatory and antipyretic potential, and also that it is safe for acute oral toxicity, which means it has potential value for treating bovine mastitis in future and alleviating clinical symptoms with no drug resistance or side effects.

Hydroxysafflor yellow A inhibits the proliferation, migration, and invasion of colorectal cancer cells through the PPARγ/PTEN/Akt signaling pathway

The natural compound Hydroxysafflor yellow A (HSYA) has been demonstrated to exert anti-cancer effect on multiple cancers. This study aimed to clarify the role of HSYA in inhibiting colorectal cancer (CRC) in vitro and the underlying mechanisms. Different concentrations of HSYA (0, 25, 50, and 100 μM) was exposed to HCT116 CRC cells, then cell proliferation, apoptosis, migration, and invasion were estimated by colony formation assay, TUNEL staining, wound-healing, and transwell assays, respectively. Western blotting assay was utilized to observe the expression of proteins involved in cell apoptosis, migration, and peroxisome proliferator-activated receptor γ (PPARγ)/PTEN/Akt signaling, including PCNA, Bax, Bcl-2, cleaved-caspase3, E-cadherin, N-cadherin, vimentin, PPARγ, and phosphorylated (p)-Akt. HCT116 cells that treated with 100 μM HSYA were also pre-treated with PPARγ antagonist, GW9662, or knockdown with PPARγ using short hairpin (sh)-RNA, to down-regulate PPARγ expression. Then, the above functional analysis was repeated. Results demonstrated that HSYA (25, 50 and 100 μM) significantly reduced HCT116 cell viability, but had no effect on the cell viability of human normal intestinal epithelial cell HIEC. HSYA also inhibited colony formation, migration, and invasion but promoted apoptosis of HCT116 cell in a concentration-dependent manner. Besides, the PPARγ/PTEN/Akt signaling was activated upon HSYA treatment. Finally, GW9662 and PPARγ knockdown blocked all the effects of HSYA on HCT116 cells. In conclusion, HSYA could exhibit anti-cancer effect on CRC via activating PPARγ/PTEN/Akt signaling, thereby inhibiting cells proliferation, migration, and invasion in vitro.

Peroxisome Proliferator-Activated Receptor-Gamma (PPAR-ɣ): Molecular Effects and Its Importance as a Novel Therapeutic Target for Cerebral Ischemic Injury

Cerebral ischemic injury is a leading cause of death and long-term disability throughout the world. Peroxisome proliferator-activated receptor gamma (PPAR-ɣ) is a ligand-activated nuclear transcription factor that is a member of the PPAR family. PPAR-ɣ has been shown in several in vitro and in vivo models to prevent post-ischemic inflammation and neuronal damage by negatively controlling the expression of genes modulated by cerebral ischemic injury, indicating a neuroprotective effect during cerebral ischemic injury. A extensive literature review of PubMed, Medline, Bentham, Scopus, and EMBASE (Elsevier) databases was carried out to understand the nature of the extensive work done on the mechanistic role of Peroxisome proliferator activated receptor gamma and its modulation in Cerebral ischemic injury. PPAR-ɣ can interact with specific DNA response elements to control gene transcription and expression when triggered by its ligand. It regulates lipid metabolism, improves insulin sensitivity, modulates antitumor mechanisms, reduces oxidative stress, and inhibits inflammation. This review article provides insights on the current state of research into the neuroprotective effects of PPAR-ɣ in cerebral ischemic injury, as well as the cellular and molecular mechanisms by which these effects are modulated, such as inhibition of inflammation, reduction of oxidative stress, suppression of pro-apoptotic production, modulation of transcription factors, and restoration of injured tissue through neurogenesis and angiogenesis.

The Agonists of Peroxisome Proliferator-Activated Receptor-γ for Liver Fibrosis

Liver fibrosis is a common link in the transformation of acute and chronic liver diseases to cirrhosis. It is of great clinical significance to study the factors associated with the induction of liver fibrosis and elucidate the method of reversal. Peroxisome proliferator-activated receptors (PPARs) are a class of nuclear transcription factors that can be activated by peroxisome proliferators. PPARs play an important role in fibrosis of various organs, especially the liver, by regulating downstream targeted pathways, such as TGF-β, MAPKs, and NF-κB p65. In recent years, the development and screening of PPAR-γ ligands have become a focus of research. The PPAR-γ ligands include synthetic hypolipidemic and antidiabetic drugs. In addition, microRNAs, lncRNAs, circRNAs and nano new drugs have attracted research interest. In this paper, the research progress of PPAR-γ in the pathogenesis and treatment of liver fibrosis was discussed based on the relevant literature in recent years.

Role of the Hippo signaling pathway in safflower yellow pigment treatment of paraquat-induced pulmonary fibrosis

OBJECTIVE

To elucidate the molecular mechanisms by which safflower yellow (SY) mediates therapeutic effects in rats with paraquat intoxication-induced pulmonary fibrosis.

METHODS

Rats received combinations of paraquat, SY, and SB431542, a transforming growth factor (TGF)-β1 receptor antagonist. Survival over 28 days was assessed by Kaplan-Meier analysis. Rat tissue and serum samples were assessed by hematoxylin and eosin staining, Masson's Trichrome staining, immunoblotting, quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and transmission electron microscopy.

RESULTS

Survival rates were higher in SY and SB431542 groups (treatment and paraquat) than in the exposure group (paraquat alone). In the exposure group, serum TGF-β1 levels increased between days 3 and 14; mammalian STE20-like (MST) levels increased between days 3 and 7; TGF-β1 and Smad3 levels increased between days 3 and 14; and Yap and connective tissue growth factor levels increased between days 3 and 28. TGF-β1 levels were lower in SY and SB431542 groups than in the exposure group. Pathology scores were higher in exposure, SY, and SB431542 groups than in the control group throughout the experiment.

CONCLUSIONS

In rats with paraquat intoxication-induced pulmonary fibrosis, Hippo signaling could be activated by the MST-Yap pathway; SY and SB431542 could alleviate pulmonary fibrosis via Hippo signaling.

A Comprehensive Review of Natural Products against Liver Fibrosis: Flavonoids, Quinones, Lignans, Phenols, and Acids

Liver fibrosis resulting from continuous long-term hepatic damage represents a heavy burden worldwide. Liver fibrosis is recognized as a complicated pathogenic mechanism with extracellular matrix (ECM) accumulation and hepatic stellate cell (HSC) activation. A series of drugs demonstrate significant antifibrotic activity in vitro and in vivo. No specific agents with ideally clinical efficacy for liver fibrosis treatment have been developed. In this review, we summarized the antifibrotic effects and molecular mechanisms of 29 kinds of common natural products. The mechanism of these compounds is correlated with anti-inflammatory, antiapoptotic, and antifibrotic activities. Moreover, parenchymal hepatic cell survival, HSC deactivation, and ECM degradation by interfering with multiple targets and signaling pathways are also involved in the antifibrotic effects of these compounds. However, there remain two bottlenecks for clinical breakthroughs. The low bioavailability of natural products should be improved, and the combined application of two or more compounds should be investigated for more prominent pharmacological effects. In summary, exploration on natural products against liver fibrosis is becoming increasingly extensive. Therefore, natural products are potential resources for the development of agents to treat liver fibrosis.

Safflower yellow improves insulin sensitivity in high-fat diet-induced obese mice by promoting peroxisome proliferator-activated receptor-γ2 expression in subcutaneous adipose tissue

Aims/Introduction

Safflower yellow (SY) and its main component, hydroxysafflor yellow A, have been demonstrated to show anti‐obesity effects. Peroxisome proliferator‐activated receptor‐γ2 (PPARγ2) is a critical transcription factor in adipose tissue metabolism. The aim of the present study was to explore the effects of SY in high‐fat diet‐induced obese mice, and further investigate the mechanism involving PPARγ2.

Methods

High‐fat diet‐induced obese mice were given 120 mg/kg/day SY for 8 weeks. Glucose and insulin tolerance tests were carried out. Fat mass and serum levels of glucose and insulin were measured. The expression of insulin signaling pathway‐related genes and PPARγ2 in the adipose tissue was measured. In vitro, the effects of SY (0–500 mg/L) and hydroxysafflor yellow A (0–100 mg/L) on PPARγ2 promoter activities and PPARγ2 messenger ribonucleic acid (mRNA) levels in 3T3‐L1 preadipocytes or adipocytes were also detected.

Results

Safflower yellow reduced fat mass, decreased glucose levels and improved insulin sensitivity in obese mice. SY also increased the mRNA levels of insulin signaling pathway‐related genes, and increased PPARγ2 mRNA levels by 39.1% in subcutaneous adipose tissue (P < 0.05). In vitro, SY and hydroxysafflor yellow A significantly enhanced PPARγ2 promoter activities by 1.3–2.1‐fold, and increased PPARγ2 mRNA levels by 1.2–1.6‐fold in 3T3‐L1 preadipocytes or adipocytes (P < 0.05).

Conclusions

SY could reduce fat mass, decrease glucose levels and improve insulin sensitivity in high‐fat diet‐induced obese mice. The probable mechanism is to increase PPARγ2 expression by stimulating PPARγ2 promoter activities, further increasing the expression of insulin signaling pathway‐related genes in subcutaneous adipose tissue.

Quercetin Inhibits Inflammatory Response Induced by LPS from Porphyromonas gingivalis in Human Gingival Fibroblasts via Suppressing NF-κB Signaling Pathway

Quercetin, a natural flavonol existing in many food resources, has been reported to be an effective antimicrobial and anti-inflammatory agent for restricting the inflammation in periodontitis. In this study, we aimed to investigate the anti-inflammatory effects of quercetin on Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide- (LPS-) stimulated human gingival fibroblasts (HGFs). HGFs were pretreated with quercetin prior to LPS stimulation. Cell viability was evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of inflammatory cytokines, including interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), along with chemokine interleukin-8 (IL-8), were determined by enzyme-linked immunosorbent assay (ELISA). The mRNA levels of IL-1β, IL-6, IL-8, TNF-α, IκBα, p65 subunit of nuclear factor-kappa B (NF-κB), peroxisome proliferator-activated receptor-γ (PPAR-γ), liver X receptor α (LXRα), and Toll-like receptor 4 (TLR4) were measured by real-time quantitative PCR (RT-qPCR). The protein levels of IκBα, p-IκBα, p65, p-p65, PPAR-γ, LXRα, and TLR4 were characterized by Western blotting. Our results demonstrated that quercetin inhibited the LPS-induced production of IL-1β, IL-6, IL-8, and TNF-α in a dose-dependent manner. It also suppressed LPS-induced NF-κB activation mediated by TLR4. Moreover, the anti-inflammatory effects of quercetin were reversed by the PPAR-γ antagonist of GW9662. In conclusion, these results suggested that quercetin attenuated the production of IL-1β, IL-6, IL-8, and TNF-α in P. gingivalis LPS-treated HGFs by activating PPAR-γ which subsequently suppressed the activation of NF-κB.

Hydroxysafflor Yellow A: A Promising Therapeutic Agent for a Broad Spectrum of Diseases

Hydroxysafflor yellow A (HSYA) is one of the major bioactive and water-soluble compounds isolated from Carthami Flos, the flower of safflower (Carthamus tinctorius L.). As a natural pigment with favorable medical use, HSYA has gained extensive attention due to broad and effective pharmacological activities since first isolation in 1993. In clinic, the safflor yellow injection which mainly contains about 80% HSYA was approved by the China State Food and Drug Administration and used to treat cardiac diseases such as angina pectoris. In basic pharmacology, HSYA has been proved to exhibit a broad spectrum of biological effects that include, but not limited to, cardiovascular effect, neuroprotection, liver and lung protection, antitumor activity, metabolism regulation, and endothelium cell protection. Although a great number of studies have been carried out to prove the pharmacological effects and corresponding mechanisms of HYSA, a systemic review of HYSA has not yet been seen. Here, we provide a comprehensive summarization of the pharmacological effects of HYSA. Together with special attention to mechanisms of actions, this review can serve as the basis for further researches and developments of this medicinal compound.

Comparison of the effect of the Dietary Approaches to Stop Hypertension diet with usual dietary advice on expression of peroxisome proliferators-activated receptor gamma gene in women: A randomized controlled clinical trial

BACKGROUND

Peroxisome proliferator-activated receptor gamma (PPAR-γ) which controls body weight, glucose homeostasis, and adipocyte differentiation is a valuable candidate gene for insulin resistance (IR). The present study aimed to compare the effects of the Dietary Approaches to Stop Hypertension (DASH) diet and usual dietary advice (UDA) on PPAR-γ gene expression in women at risk for cardiovascular disease (CVD).

METHODS

This randomized controlled trial was performed on 44 women aged 20-50 years at risk for CVD (BMI > 25 kg/m2 and low physical activity). Participants were randomly assigned to the UDA (n = 22) or DASH (n = 22) diets for 12 weeks. The DASH diet was rich in fruits, vegetables, whole grains and low-fat dairy products and low in saturated fat, total fat, cholesterol, refined grains and sweets, with a total of 2400 mg/day sodium. The UDA diet was a regular diet with healthy dietary advice. Anthropometric indices and PPAR-γ gene expression were measured and compared between the two groups at the end of the study.

RESULTS

After the intervention, body mass index (BMI) and waist circumference (WC) significantly decreased in the DASH group (P < 0.050) but the results showed no significant differences between the two groups. At the end of the trial, PPAR-γ gene expression was significantly different between the UDA and the DASH diet groups (P = 0.040) and this difference remained significant after adjustment for BMI, and physical activity (P = 0.030).

CONCLUSION

The result of the study showed that the DASH diet significantly decreased the expression of PPAR-γ. This finding was unexpected and future studies on the current topic are therefore recommended.

The Active Components of Fuzheng Huayu Formula and Their Potential Mechanism of Action in Inhibiting the Hepatic Stellate Cells Viability - A Network Pharmacology and Transcriptomics Approach

Purpose: This study aimed to identify the active components of Fuzheng Huayu (FZHY) formula and the mechanism by which they inhibit the viability of hepatic stellate cells (HSCs) by a combination of network pharmacology and transcriptomics.

Methods: The active components of FZHY formula were screened out by text mining. Similarity match and molecular docking were used to predict the target proteins of these compounds. We then searched the STRING database to analyze the key enriched processes, pathways and related diseases of these target proteins. The relevant networks were constructed by Cytoscape. A network analysis method was established by integrating data from above network pharmacology with known transcriptomics analysis of quiescent HSCs-activated HSCs to identify the most possible targets of the active components in FZHY formula. A cell-based assay (LX-2 and T6 cells) and surface plasmon resonance (SPR) analysis were used to validate the most possible active component-target protein interactions (CTPIs).

Results: 40 active ingredients in FZHY formula and their 79 potential target proteins were identified by network pharmacology approach. Further network analysis reduced the 79 potential target proteins to 31, which were considered more likely to be the target proteins of the active components in FZHY formula. In addition, further enrichment analysis of 31 target proteins indicated that the HIF-1, PI3K-Akt, FoxO, and chemokine signaling pathways may be the primary pathways regulated by FZHY formula in inhibiting the HSCs viability for the treatment of liver fibrosis. Of the 31 target proteins, peroxisome proliferator activator receptor gamma (PPARG) was selected for validation by experiments at the cellular and molecular level. The results demonstrated that schisandrin B, salvianolic acid A and kaempferol could directly bind to PPARG, decreasing the viability of HSCs (T6 cells and LX-2 cells) and exerting anti-fibrosis effects.

Conclusion: The active ingredients of FZHY formula were successfully identified and the mechanisms by which they inhibit HSC viability determined, using network pharmacology and transcriptomics. This work is expected to benefit the clinical application of this formula.

Animal Models of Nonalcoholic Fatty Liver Disease-A Starter's Guide

Nonalcoholic fatty liver disease (NAFLD) constitutes a major health concern with the increasing incidence of obesity and diabetes in many Western countries, reaching a prevalence of up to 30% in the general population. Animal models have played a vital role in elucidating the pathophysiological mechanisms of NAFLD and continue to do so. A myriad of different models exists, each with its advantages and disadvantages. This review presents a brief overview of these models with a particular focus on the basic mechanisms and physical, biochemical and histological phenotype. Both nutritional and chemically induced, as well as genetic models are examined, including models combining different approaches.

Hydroxysafflor Yellow A Suppresses MRC-5 Cell Activation Induced by TGF-β1 by Blocking TGF-β1 Binding to TβRII

Hydroxysafflor yellow A (HSYA) is an active ingredient of Carthamus tinctorius L.. This study aimed to evaluate the effects of HSYA on transforming growth factor-β1 (TGF-β1)-induced changes in proliferation, migration, differentiation, and extracellular matrix accumulation and degradation in human fetal lung fibroblasts (MRC-5), to explore the mechanisms whereby HSYA may alleviate pulmonary fibrosis. MRC-5 cells were incubated with various doses of HSYA and/or the TGF-β receptor type I kinase inhibitor SB431542 and then stimulated with TGF-β1. Cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium inner salt assay. Cell migration was detected by wound-healing assay. Protein levels of α-smooth muscle actin (α-SMA), collagen I α 1 (COL1A1), and fibronectin (FN) were measured by immunofluorescence. Protein levels of matrix metalloproteinase-2, tissue inhibitor of matrix metalloproteinase-1, tissue inhibitor of matrix metalloproteinase-2, TGF-β type II receptor (TβRII), and TGF-β type I receptor were detected by western blotting. TβRII knockdown with siRNA interfered with the inhibitory effect of HSYA on α-SMA, COL1A1, and FN expression, and TGF-β1-induced Sma and Mad protein (Smad), and extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway activation. The antagonistic effect of HSYA on the binding of fluorescein isothiocyanate-TGF-β1 to MRC-5 cell cytoplasmic receptors was measured by flow cytometry. HSYA significantly suppressed TGF-β1-induced cell proliferation and migration. HSYA could antagonize the binding of FITC-TGF-β1 to MRC-5 cell cytoplasmic receptors. Also HSYA inhibited TGF-β1-activated cell expression of α-SMA, COL1A1, and FN and phosphorylation level of Smad2, Smad3, and ERK by targeting TβRII in MRC-5 cells. These findings suggest that TβRII might be the target responsible for the inhibitory effects of HSYA on TGF-β1-induced pathological changes in pulmonary fibrosis.

Can Ultrasound Imaging Predict the Success of an Experimental Steatofibrosis Model?

Our goal was to evaluate the role of ultrasound (US) imaging in an experimental 2-hit steatofibrosis rat model. Nineteen female Sprague-Dawley rats were divided into 2 groups: control group (n = 6) and high-fat diet carbontetrachloride (HFD-CCl4) group (n = 13) that was fed with HFD for 14 weeks. Ultrasound was performed to evaluate liver steatosis. The HFD-CCl4 group rats were divided further into 2 subgroups: HFD rats with liver steatosis [US (+) group; n = 6] and without steatosis [US (-) group; n = 7]. All rats in the subgroups were administered with CCl4. In both US (+) and US (-) subgroups, steatosis score, fibrosis score, triglyceride, and hydroxyproline contents were markedly higher compared with the control group. When compared with the US (-) group, triglyceride and hydroxyproline contents were significantly higher in the US (+) group, whereas steatosis and fibrosis scores were not different. Ultrasound imaging may be useful to assess the success of a 2-hit experimental steatofibrosis model.

Nuclear Receptors as Therapeutic Targets in Liver Disease: Are We There Yet?

Nuclear receptors (NR) are ligand-modulated transcription factors that play diverse roles in cell differentiation, development, proliferation, and metabolism and are associated with numerous liver pathologies such as cancer, steatosis, inflammation, fibrosis, cholestasis, and xenobiotic/drug-induced liver injury. The network of target proteins associated with NRs is extremely complex, comprising coregulators, small noncoding microRNAs, and long noncoding RNAs. The importance of NRs as targets of liver disease is exemplified by the number of NR ligands that are currently used in the clinics or in clinical trials with promising results. Understanding the regulation by NR during pathophysiological conditions, and identifying ligands for orphan NR, points to a potential therapeutic approach for patients with liver diseases. An overview of complex NR metabolic networks and their pharmacological implications in liver disease is presented here.

Herbal medicines and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), which is characterized by excessive fat accumulation in the liver of patients who consume little or no alcohol, becomes increasingly common with rapid economic development. Long-term excess fat accumulation leads to NAFLD and represents a global health problem with no effective therapeutic approach. NAFLD is considered to be a series of complex, multifaceted pathological processes involving oxidative stress, inflammation, apoptosis, and metabolism. Over the past decades, herbal medicines have garnered growing attention as potential therapeutic agents to prevent and treat NAFLD, due to their high efficacy and low risk of side effects. In this review, we evaluate the use of herbal medicines (including traditional Chinese herbal formulas, crude extracts from medicinal plants, and pure natural products) to treat NAFLD. These herbal medicines are natural resources that can inform innovative drug research and the development of treatments for NAFLD in the future.

High-fat diet plus carbon tetrachloride-induced liver fibrosis is alleviated by betaine treatment in rats

Steatosis, the first lesion in non-alcoholic fatty liver disease (NAFLD), may progress to fibrosis, cirrhosis, and hepatocellular carcinoma. Steatosis predisposes the liver to oxidative stress, inflammation, and cytokines. Betaine (BET) has antioxidant, antiinflammatory and hepatoprotective effects. However, the effects of BET on liver fibrosis development are unknown. Rats were treated with high-fat diet (60% of total calories from fat) for 14weeks. Carbon tetrachloride (0.2mL/kg; two times per week; i.p.) was administered to rats in the last 6weeks with/without commercial food containing BET (2%; w/w). Serum liver function tests and tumor necrosis factor-α, insulin resistance, hepatic triglyceride (TG) and hydroxyproline (HYP) levels and oxidative stress parameters were determined along with histopathologic observations. Alpha-smooth muscle-actin (α-SMA), transforming growth factor-β1 (TGF-β1) and type I collagen (COL1A1) protein expressions and mRNA expressions of matrix metalloproteinase-2 (MMP-2) and its inhibitors (TIMP-1 and TIMP-2) were evaluated. BET decreased TG and HYP levels, prooxidant status and fibrotic changes in the liver. α-SMA, COL1A1 and TGF-β1 protein expressions, MMP-2, TIMP-1, and TIMP-2 mRNA expressions diminished due to BET treatment. BET has an antifibrotic effect and this effect may be related to its antioxidant and antiinflammatory actions together with suppression on HSC activation.

Hydroxysafflor yellow A inhibits TGF-β1-induced activation of human fetal lung fibroblasts in vitro

Objective

Hydroxysafflor yellow A (HSYA) is one of the chemical component isolated from Chinese medicine Carthamus tinctorius L. Our preliminary study confirmed that HSYA attenuated bleomycin-induced pulmonary fibrosis in mice. In this study, we evaluated the effect of HSYA on TGF-β1-induced activation of human fetal lung fibroblasts (MRC-5) and explored the underlying mechanisms of its activity.

Method

MRC-5 cells activated by TGF-β1 were incubated with HSYA and/or the TGF-β type I receptor inhibitor, SB431542. TGF-β1-induced cell proliferation, α-smooth muscle actin, collagen I alpha 1 and fibronectin expression, Smad, mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3 kinase/Akt signalling pathway activation were observed.

Key findings

Hydroxysafflor yellow A significantly inhibited TGF-β1-induced cell proliferation and the expression, both mRNA and protein, of α-smooth muscle actin, collagen I alpha 1 and fibronectin. HSYA also suppressed TGF-β1 activation of Smad signal transduction via inhibition of Smad2 and Smad3 phosphorylation, their nuclear translocation and the binding activity of Smad3 to type I collagen promoter in MRC-5 cells. In addition, HSYA inhibited TGF-β1-induced phosphorylation of extracellular signal-regulated kinase (ERK). The inhibitory effects of HSYA were similar to SB431542.

Conclusion

These findings suggest that HSYA inhibits TGF-β1-induced activation of MRC-5 cells associated with TGF-β1/Smad and ERK/MAPK signalling pathways.

Chinese Herbal Preparation Xuebijing Potently Inhibits Inflammasome Activation in Hepatocytes and Ameliorates Mouse Liver Ischemia-Reperfusion Injury

The Chinese herb preparation Xuebijing injection (XBJ) has been widely used in the management of various septic disorders or inflammation-related conditions, however the molecular mechanism of its anti-inflammatory effect remains largely elusive. In the current study, we found that XBJ treatment potently ameliorated mouse hepatic ischemia-reperfusion (IR) injury, manifested as decreased liver function tests (LDH, ALT, AST), improved inflammation and less hepatocyte apoptosis. Notably, XBJ markedly inhibited inflammasome activation and IL-1 production in mouse livers subjected to IRI, even in the absence of Kupffer cells, suggesting Kupffer cells are not necessary for hepatic inflammasome activation upon Redox-induced sterile inflammation. This finding led us to investigate the role of XBJ on hepatocyte apoptosis and inflammasome activation using an in vitro hydrogen peroxide (H₂O₂)-triggered hepatocyte injury model. Our data clearly demonstrated that XBJ potently inhibited apoptosis, as well as caspase-1 cleavage and IL-1β production in a time- and dose-dependent manner in isolated hepatocytes, suggesting that in addition to its known modulatory effect on NF-κB-dependent inflammatory gene expression, it also has a direct impact on hepatocyte inflammasome activation. The current study not only deepens our understanding of how XBJ ameliorates inflammation and apoptosis, but also has immediate practical significance in many clinical situations such as partial hepatectomy, liver transplantation, etc.

Hydroxysafflor yellow A inhibits angiogenesis of hepatocellular carcinoma via blocking ERK/MAPK and NF-κB signaling pathway in H22 tumor-bearing mice

Hydroxysafflor yellow A (HSYA), a flavonoid derived and isolated from traditional Chinese medicine Carthamus tinctorius L., possesses anti-tumor activity. However, its effects on hepatocellular carcinoma (HCC) have not been investigated. The proliferation and metastasis of HCC are dependent on angiogenesis, which also strongly links with several signal transduction pathways associated with cell proliferation and apoptosis. This study aimed to explore the effect of HSYA on vasculogenesis and to determine its molecular mechanism by investigating the expression of ERK/MAPK (p-c-Raf, c-Raf, p-ERK1/2, ERK1/2) and NF-κB (p65, IκB and p-IκB) signaling pathway in H22 tumor-bearing mice. The results showed that HSYA could considerably suppress tumor growth by inhibiting secretion of angiogenesis factors (vascular endothelial growth factor A, basic fibroblast growth factor) and vascular endothelial growth factor receptor1. At the moleculcould block ERK1/2 phosphorylation and then restrain the activation of NF-κB and its nuclear translocation by down-regulating the expression of p65 in the nucleus, up-regulating p65 level in the cytoplasm, inhibiting IκB phosphorylation and cytoplasmic degradation of IκB-α. Finally, we demonstrate that HSYA could suppress mRNA expression levels of cell proliferation-related genes (cyclinD1, c-myc, c-Fos) compared with negative control group. And best of all, HSYA could improve spleen/thymus indexes, which was evaluated as the marker of protective effect on the immune system. Our findings support HSYA as a promising candidate for the prevention and treatment of HCC.