Alpinetin exerts anti-inflammatory, anti-oxidative and anti-angiogenic effects through activating the Nrf2 pathway and inhibiting NLRP3 pathway in carbon tetrachloride-induced liver fibrosis

Histidine-rich glycoprotein inhibits TNF-α-induced tube formation in human vascular endothelial cells

Introduction

Tumor necrosis factor-α (TNF-α)-induced angiogenesis plays a critical role in tumor progression and metastasis, making it an important therapeutic target in cancer treatment. Suppressing angiogenesis can effectively limit tumor growth and metastasis. However, despite advancements in understanding angiogenic pathways, effective strategies to inhibit TNF-α-mediated angiogenesis remain limited.

Methods

This study investigates the antiangiogenic effects of histidine-rich glycoprotein (HRG), a multifunctional plasma protein with potent antiangiogenic properties, on TNF-α-stimulated human endothelial cells (EA.hy926). Tube formation assays were performed to assess angiogenesis, and gene/protein expression analyses were conducted to evaluate HRG's effects on integrins αV and β8. The role of nuclear factor erythroid 2-related factor 2 (NRF2) in HRG-mediated antiangiogenic activity was also examined through nuclear translocation assays and NRF2 activation studies.

Results

At physiological concentrations, HRG effectively suppressed TNF-α-induced tube formation in vitro and downregulated TNF-α-induced expression of integrins αV and β8 at both the mRNA and protein levels. HRG treatment promoted NRF2 nuclear translocation in a time-dependent manner. Furthermore, activation of NRF2 significantly reduced TNF-α-induced tube formation and integrin expression, suggesting that NRF2 plays a key role in HRG-mediated antiangiogenic effects.

Discussion and Conclusion

Our findings indicate that HRG suppresses TNF-α-induced angiogenesis by promoting NRF2 nuclear translocation and transcriptional activation, which in turn inhibits integrin αV and β8 expression. Given the essential role of angiogenesis in tumor progression, HRG's ability to regulate this process presents a promising therapeutic strategy for cancer treatment.

Portulaca oleracea L. extract relieve mice liver fibrosis by inhibiting TLR-4/NF-κB, Bcl-2/Bax and TGF-β1/Smad2 signalling transduction

Portulaca oleracea L. are annual herb, which has various pharmacological effects including hepatoprotective property. However, the effect of Portulaca oleracea L. (POL-1) in mice with carbon tetrachloride (CCl4)-induced liver fibrosis and its mechanism of action have not been clarified. POL-1 ameliorated the CCl4-induced liver fibrosis in mice, as shown by decreased collagen deposition and the decreased expression of liver fibrosis marker collagen I and α-smooth muscle actin (α-SMA) mRNA. In addition, treatment with POL-1 suppressed the proliferation of activated human hepatic stellate cell line (LX-2). POL-1 inhibited the oxidative stress and inflammation in fibrotic livers of mice. Mechanistically, POL-1 inhibited the CCl4-induced expression of toll-like receptor-4 (TLR4), myeloid differentiation factor 88 (MyD88), nuclear factor kappa-B (NF-κBp65) p65, Bcl2-associated X (Bax), transforming growth factor-β1 (TGF-β1) and drosophila mothers against decapentaplegic 2 (Smad2) proteins, upregulated B-cell lymphoma -2 (Bcl-2) proteins in livers of mice. These findings suggested that POL-1 attenuated liver fibrosis.

Metabolic dysfunction-associated steatotic liver disease-induced changes in the antioxidant system: a review

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a heterogeneous condition characterized by liver steatosis, inflammation, consequent fibrosis, and cirrhosis. Chronic impairment of lipid metabolism is closely related to oxidative stress, leading to cellular lipotoxicity, mitochondrial dysfunction, and endoplasmic reticulum stress. The detrimental effect of oxidative stress is usually accompanied by changes in antioxidant defense mechanisms, with the alterations in antioxidant enzymes expression/activities during MASLD development and progression reported in many clinical and experimental studies. This review will provide a comprehensive overview of the present research on MASLD-induced changes in the catalytic activity and expression of the main antioxidant enzymes (superoxide dismutases, catalase, glutathione peroxidases, glutathione S-transferases, glutathione reductase, NAD(P)H:quinone oxidoreductase) and in the level of non-enzymatic antioxidant glutathione. Furthermore, an overview of the therapeutic effects of vitamin E on antioxidant enzymes during the progression of MASLD will be presented. Generally, at the beginning of MASLD development, the expression/activity of antioxidant enzymes usually increases to protect organisms against the increased production of reactive oxygen species. However, in advanced stage of MASLD, the expression/activity of several antioxidants generally decreases due to damage to hepatic and extrahepatic cells, which further exacerbates the damage. Although the results obtained in patients, in various experimental animal or cell models have been inconsistent, taken together the importance of antioxidant enzymes in MASLD development and progression has been clearly shown.

Exploring the cytoprotective role of mesenchymal stem Cell-Derived exosomes in chronic liver Fibrosis: Insights into the Nrf2/Keap1/p62 signaling pathway

Hepatic fibrosis is a common pathology present in most chronic liver diseases. Autophagy is a lysosome-mediated intracellular catabolic and recycling process that plays an essential role in maintaining normal hepatic functions. Nuclear factor erythroid 2-like 2 (Nrf2) is a transcription factor responsible for the regulation of cellular anti-oxidative stress response. This study was designed to assess the cytoprotective effect of mesenchymal stem cell-derived exosomes (MSC-exos) on endothelial-mesenchymal transition (EMT) in Carbon Tetrachloride (CCL4) induced liver fibrosis. Rats were treated with 0.1 ml of CCL4 twice weekly for 8 weeks, followed by administration of a single dose of MSC-exos. Rats were then sacrificed after 4 weeks, and liver samples were collected for gene expression analyses, Western blot, histological studies, immunohistochemistry, and transmission electron microscopy. Our results showed that MSC-exos administration decreased collagen deposition, apoptosis, and inflammation. Exosomes modulate the Nrf2/Keap1/p62 pathway, restoring autophagy and Nrf2 levels through modulation of the non-canonical pathway of Nrf2/Keap1/p62. Additionally, MSC-exos regulated miR-153-3p, miR-27a, miR-144 and miRNA-34a expression. In conclusion, the present study shed light on MSC-exos as a cytoprotective agent against EMT and tumorigenesis in chronic liver inflammation.

Protective effects of alpinetin against interleukin-1β-exposed nucleus pulposus cells: Involvement of the TLR4/MyD88 pathway in a cellular model of intervertebral disc degeneration

Intervertebral disc degeneration (IDD) causes a variety of symptoms such as low back pain, disc herniation, and spinal stenosis, which can lead to high social and economic costs. Alpinetin has an anti-inflammatory potential, but its effect on IDD is unclear. Herein, we investigated the effect of alpinetin on IDD. To mimic an in vitro model of IDD, nucleus pulposus cells (NPCs) were exposed to interleukin 1β (IL-1β). The viability of NPCs was assessed by CCK-8 assay. The expression of Toll-like receptor 4 (TLR4), myeloid differentiation primary response protein 88 (MyD88), aggrecan, collagen-2, and matrix metalloproteinase-3 (MMP-3) was examined by qRT-PCR and western blotting. The protein levels of B cell lymphoma-2 (Bcl-2), Bcl-2-associated protein X (Bax), and cleaved caspase-3 were scrutinized by western blotting. The flow cytometry assay was performed to assess apoptosis of NPCs. The contents of inflammatory factors were examined by ELISA kits. Results showed that alpinetin repressed IL-1β-tempted activation of the TLR4/MyD88 pathway and apoptosis in NPCs. Alpinetin alleviated IL-1β-tempted inflammatory responses and oxidative stress in NPCs. Moreover, alpinetin lessened IL-1β-tempted extracellular matrix (ECM) degeneration in NPCs by enhancing the expression of aggrecan and collagen-2 and reducing the expression of MMP-3. The effects of alpinetin on IL-1β-exposed NPCs were neutralized by TLR4 upregulation. In conclusion, alpinetin repressed IL-1β-tempted apoptosis, inflammatory responses, oxidative stress, and ECM degradation in NPCs through the inactivation of the TLR4/MyD88 pathway.

The potential of flavonoids in hepatic fibrosis: A comprehensive review

BACKGROUND

Hepatic fibrosis is a pathophysiological process of extracellular matrix abnormal deposition induced by multiple pathogenic factors. Currently, there is still a lack of effective and non-toxic drugs for treating fibrosis in clinic. Flavonoids are polyphenolic compounds synthesized in plants and modern pharmacological studies confirmed flavonoids exhibit potent hepatoprotective effect.

PURPOSE

Summarize literature to elaborate the mechanism of HF and evaluate the potential of flavonoids in HF, aiming to provide a new perspective for future research.

METHODS

The literatures about hepatic fibrosis and flavonoids are collected via a series of scientific search engines including Google Scholar, Elsevier, PubMed, CNKI, WanFang, SciFinder and Web of Science database. The key words are "flavonoids", "hepatic fibrosis", "pharmacokinetic", "toxicity", "pathogenesis" "traditional Chinese medicine" and "mechanism" as well as combination application.

RESULTS

Phytochemical and pharmacological studies revealed that about 86 natural flavonoids extracted from Chinese herbal medicines possess significantly anti-fibrosis effect and the mechanisms maybe through anti-inflammatory, antioxidant, inhibiting hepatic stellate cells activation and clearing activated hepatic stellate cells.

CONCLUSIONS

This review summarizes the flavonoids which are effective in HF and the mechanisms in vivo and in vitro. However, fewer studies are focused on the pharmacokinetics of flavonoids in HF model and most studies are limited to preclinical studies, therefore there is no reliable data from clinical trials for the development of new drugs. Further in-depth research related it can be conducted to improve the bioavailability of flavonoids and serve the development of new drugs.

Advancements in Plant-Based Therapeutics for Hepatic Fibrosis: Molecular Mechanisms and Nanoparticulate Drug Delivery Systems

Chronic liver injuries often lead to hepatic fibrosis, a condition characterized by excessive extracellular matrix accumulation and abnormal connective tissue hyperplasia. Without effective treatment, hepatic fibrosis can progress to cirrhosis or hepatocellular carcinoma. Current treatments, including liver transplantation, are limited by donor shortages and high costs. As such, there is an urgent need for effective therapeutic strategies. This review focuses on the potential of plant-based therapeutics, particularly polyphenols, phenolic acids, and flavonoids, in treating hepatic fibrosis. These compounds have demonstrated anti-fibrotic activities through various signaling pathways, including TGF-β/Smad, AMPK/mTOR, Wnt/β-catenin, NF-κB, PI3K/AKT/mTOR, and hedgehog pathways. Additionally, this review highlights the advancements in nanoparticulate drug delivery systems that enhance the pharmacokinetics, bioavailability, and therapeutic efficacy of these bioactive compounds. Methodologically, this review synthesizes findings from recent studies, providing a comprehensive analysis of the mechanisms and benefits of these plant-based treatments. The integration of novel drug delivery systems with plant-based therapeutics holds significant promise for developing effective treatments for hepatic fibrosis.

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.

Alpinetin alleviates LPS-induced lung epithelial cell injury by inhibiting p38 and ERK1/2 signaling via aquaporin-1

Alpinetin has been reported to play a protective role in lung diseases, while its special mechanisms remain indistinct. In this study, acute lung injury (ALI) model was constructed by inducing MLE-12 cells with lipopolysaccharide (LPS). Cell activity together with apoptosis was judged employing cell counting kit-8 (CCK-8), flow cytometry along with western blot. Oxidative stress levels were measured by dichloro-dihydro-fluorescein diacetate (DCFH-DA) staining and corresponding kits. In addition, enzyme-linked immunosorbent assay (ELISA) was to examine the levels of inflammatory factors. The protein expressions of aquaporin-1 (AQP1), p38 and extracellular signal-regulated kinase (ERK) 1/2 pathway were estimated utilizing western blot. The data showed that alpinetin increased the viability, reduced the apoptosis, oxidative stress and inflammation and inactivated p38 and ERK1/2 signaling in LPS-induced MLE-12 cells. Moreover, alpinetin also increased AQP1 expression and AQP1 knockdown reversed the impacts of alpinetin on LPS-induced MLE-12 cells. Additionally, AQP1 agonist AqF026 also exerted anti-apoptotic and anti-inflammatory activities in LPS-treated MLE-12 cells. Evidently, alpinetin may exert its protective role in LPS-induced ALI by inactivation of p38 and ERK1/2 signaling through regulating AQP1.

Alpinetin ameliorates bleomycin-induced pulmonary fibrosis by repressing fibroblast differentiation and proliferation

OBJECTIVE

Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible interstitial lung disease with a poor prognosis. Alpinetin (ALP), derived from Alpinia katsumadai Hayata, has shown potential as a therapeutic measure of various diseases. However, the utilization of ALP in managing pulmonary fibrosis and its underlying mechanisms are still not fully understood.

METHODS

A well-established mouse model of pulmonary fibrosis induced by bleomycin (BLM) was used in this study. The antifibrotic effects of ALP on histopathologic manifestations and expression levels of fibrotic markers were examined. Subsequently, the impact of ALP on fibroblast differentiation, proliferation, apoptosis, and associated signaling pathways was investigated to elucidate the underlying mechanisms.

RESULTS

In the present study, we observed that ALP effectively mitigated BLM-induced pulmonary fibrosis in mice, as evidenced by histopathological manifestations and the expression levels of fibrotic markers. Furthermore, the in vitro experiments demonstrated that ALP treatment attenuated the ability of fibroblasts to differentiate into myofibroblasts. Mechanically, our findings provided evidence that ALP suppressed fibroblast-to-myofibroblast differentiation by repressing TGF-β/ALK5/Smad signaling pathway. ALP was found to possess the capability of inhibiting fibroblast proliferation and promoting apoptosis of fibroblasts induced by TGF-β.

CONCLUSION

In general, ALP may exert therapeutic effects on pulmonary fibrosis by modulating the differentiation, proliferation, and apoptosis of fibroblasts. Although its safety has been demonstrated in mice, further studies are required to investigate the efficacy of ALP in treatment of patients with IPF.

Chinese herbal medicines: The modulator of nonalcoholic fatty liver disease targeting oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

Plants are a natural treasure trove; their secondary metabolites participate in several pharmacological processes, making them a crucial component in the synthesis of novel pharmaceuticals and serving as a reserve resource foundation in this process. Nonalcoholic fatty liver disease (NAFLD) is associated with the risk of progression to hepatitis and liver cancer. The "Treatise on Febrile Diseases," "Compendium of Materia Medica," and "Thousand Golden Prescriptions" have listed herbal remedies to treat liver diseases.

AIM OF THE REVIEW

Chinese herbal medicines have been widely used for the prevention and treatment of NAFLD owing to their efficacy and low side effects. The production of reactive oxygen species (ROS) during NAFLD, and the impact and potential mechanism of ROS on the pathogenesis of NAFLD are discussed in this review. Furthermore, common foods and herbs that can be used to prevent NAFLD, as well as the structure-activity relationships and potential mechanisms, are discussed.

METHODS

Web of Science, PubMed, CNKI database, Google Scholar, and WanFang database were searched for natural products that have been used to treat or prevent NAFLD in the past five years. The primary search was performed using the following keywords in different combinations in full articles: NAFLD, herb, natural products, medicine, and ROS. More than 400 research papers and review articles were found and analyzed in this review.

RESULTS

By classifying and discussing the literature, we obtained 86 herbaceous plants, 28 of which were derived from food and 58 from Chinese herbal medicines. The mechanism of NAFLD was proposed through experimental studies on thirteen natural compounds (quercetin, hesperidin, rutin, curcumin, resveratrol, epigallocatechin-3-gallate, salvianolic acid B, paeoniflorin, ginsenoside Rg1, ursolic acid, berberine, honokiol, emodin). The occurrence and progression of NAFLD could be prevented by natural antioxidants through several pathways to prevent ROS accumulation and reduce hepatic cell injuries caused by excessive ROS.

CONCLUSION

This review summarizes the natural products and routinely used herbs (prescription) in the prevention and treatment of NAFLD. Firstly, the mechanisms by which natural products improve NAFLD through antioxidant pathways are elucidated. Secondly, the potential of traditional Chinese medicine theory in improving NAFLD is discussed, highlighting the safety of food-medicine homology and the broader clinical potential of multi-component formulations in improving NAFLD. Aiming to provide theoretical basis for the prevention and treatment of NAFLD.

Mechanism of Action and Related Natural Regulators of Nrf2 in Nonalcoholic Fatty Liver Disease

With the acceleration of people's pace of life, non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease in the world, which greatly threatens people's health and safety. Therefore, there is still an urgent need for higher-quality research and treatment in this area. Nuclear factor Red-2-related factor 2 (Nrf2), as a key transcription factor in the regulation of oxidative stress, plays an important role in inducing the body's antioxidant response. Although there are no approved drugs targeting Nrf2 to treat NAFLD so far, it is still of great significance to target Nrf2 to alleviate NAFLD. In recent years, studies have reported that many natural products treat NAFLD by acting on Nrf2 or Nrf2 pathways. This article reviews the role of Nrf2 in the pathogenesis of NAFLD and summarizes the currently reported natural products targeting Nrf2 or Nrf2 pathway for the treatment of NAFLD, which provides new ideas for the development of new NAFLD-related drugs.

Recent Advances in Research on Active Compounds Against Hepatic Fibrosis

BACKGROUND

Almost all chronic liver diseases cause fibrosis, which can lead to cirrhosis and eventually liver cancer. Liver fibrosis is now considered to be a reversible pathophysiological process and suppression of fibrosis is necessary to prevent liver cancer. At present, no specific drugs have been found that have hepatic anti-fibrotic activity.

OBJECTIVE

The research progress of anti-hepatic fibrosis compounds in recent ten years was reviewed to provide a reference for the design and development of anti-hepatic fibrosis drugs.

METHODS

According to the structure of the compounds, they are divided into monocyclic compounds, fused-heterocyclic compounds, and acyclic compounds.

RESULTS

In this article, the natural products and synthetic compounds with anti-fibrotic activity in recent ten years were reviewed, with emphasis on their pharmacological activity and structure-activity relationship (SAR).

CONCLUSION

Most of these compounds are natural active products and their derivatives, and there are few researches on synthetic compounds and SAR studies on natural product.

Research progress of traditional Chinese medicine in improving hepatic fibrosis based on inhibiting pathological angiogenesis

Hepatic fibrosis is the formation of scar tissue in the liver. This scar tissue replaces healthy liver tissue and can lead to liver dysfunction and failure if left untreated. It is usually caused by chronic liver disease, such as hepatitis B or C, alcohol abuse, or non-alcoholic fatty liver disease. Pathological angiogenesis plays a crucial role in the development of hepatic fibrosis by promoting the growth of new blood vessels in the liver. These new vessels increase blood flow to the damaged areas of the liver, which triggers the activation of hepatic stellate cells (HSCs). HSCs are responsible for producing excess collagen and other extracellular matrix proteins that contribute to the development of fibrosis. Pathological angiogenesis plays a crucial role in the development of hepatic fibrosis by promoting the growth of new blood vessels in the liver. These new vessels increase blood flow to the damaged areas of the liver, which triggers the activation of HSCs. HSCs are responsible for producing excess collagen and other extracellular matrix proteins that contribute to the development of fibrosis. Traditional Chinese medicine (TCM) has been found to target pathological angiogenesis, thereby providing a potential treatment option for hepatic fibrosis. Several studies have demonstrated that TCM exhibits anti-angiogenic effects by inhibiting the production of pro-angiogenic factors, such as vascular endothelial growth factor and angiopoietin-2, and by reducing the proliferation of endothelial cells. Reviewing and highlighting the unique TCM recognition of treating hepatic fibrosis by targeting pathological angiogenesis may shed light on future hepatic fibrosis research.

Amomum subulatum fruits protect against radiation-induced esophagitis by regulating antioxidant status and inflammatory responses

Radiation esophagitis (RE) is an inimical event that requires proper management while carrying out radiotherapy for thoracic cancers. The present study investigates the protective effect of dry fruits of the culinary and folkloric spice Amomum subulatum against experimental thoracic radiation-induced esophagitis. C57BL/6 mice were subjected to 25 Gy whole thorax irradiation and administered with 250 mg/kg body weight of methanolic extract of A. subulatum dry fruits (MEAS) orally for four consecutive weeks. Changes in tissue antioxidant activities, oxidative stress parameters, expression of antioxidant, inflammation, and fibrosis-related genes were observed. Administration of MEAS boosted antioxidant status, thereby reducing radiation-induced oxidative stress in the esophagus. PCR (polymerase chain reaction) results showed decreased expression of apoptosis, inflammation, and fibrosis-associated genes as well as increased expression of vital cytoprotective and antioxidant genes in MEAS-treated mice, manifesting its protective effect against radiation-induced oxidative stress, inflammatory responses, and fibrosis in the esophagus. Further, histopathology, immunohistochemistry (Cyclooxygenase-2), and Masson's Trichrome staining ascertained the protective effect of MEAS in alleviating radiation-induced esophageal injury. The synergistic effect of bioactive phytochemicals in MEAS with potent antioxidant and anti-inflammatory efficacies might have contributed to its mitigating effect against RE. Taken together, our results ascertained the radioprotective potential of MEAS, suggesting its possible nutraceutical application as a radiation countermeasure.

Progress on traditional Chinese medicine in improving hepatic fibrosis through inhibiting oxidative stress

Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer, characterized by excessive deposition of the extracellular matrix. In the past, hepatic fibrosis was thought to be a static and irreversible pathological process. In recent years, with the rapid development of molecular biology and the continuous in-depth study of the liver at the microscopic level, more and more evidence has shown that hepatic fibrosis is a dynamic and reversible process. Therefore, it is particularly important to find an effective, simple, and inexpensive method for its prevention and treatment. Traditional Chinese medicine (TCM) occupies an important position in the treatment of hepatic fibrosis due to its advantages of low adverse reactions, low cost, and multi-target effectiveness. A large number of research results have shown that TCM monomers, single herbal extracts, and TCM formulas play important roles in the prevention and treatment of hepatic fibrosis. Oxidative stress (OS) is one of the key factors in the occurrence and development of hepatic fibrosis. Therefore, this article reviews the progress in the understanding of the mechanisms of TCM monomers, single herbal extracts, and TCM formulas in preventing and treating hepatic fibrosis by inhibiting OS in recent years, in order to provide a reference and basis for drug therapy of hepatic fibrosis.

NOD-like receptors in the pathogenesis of metabolic (dysfunction)-associated fatty liver disease: Therapeutic agents targeting NOD-like receptors

BACKGROUND AND AIMS

In metabolic (dysfunction)-associated fatty liver disease (MAFLD), activation of inflammatory processes marks the transition of simple steatosis to steatohepatitis, which can further evolve to advanced fibrosis or hepatocellular carcinoma. Under the stress of chronic overnutrition, the innate immune system orchestrates hepatic inflammation through pattern recognition receptors (PRRs). Cytosolic PRRs that include NOD-like receptors (NLRs) are crucial for inducing inflammatory processes in the liver.

METHODS

A literature search was performed with Medline (PubMed), Google Scholar and Scopus electronic databases till January 2023, using relevant keywords to extract studies describing the role of NLRs in the pathogenesis of MAFLD.

RESULTS

Several NLRs operate through the formation of inflammasomes, which are multimolecular complexes that generate pro-inflammatory cytokines and induce pyroptotic cell death. A multitude of pharmacological agents target NLRs and improve several aspects of MAFLD. In this review, we discuss the current concepts related to the role of NLRs in the pathogenesis of MAFLD and its complications. We also discuss the latest research on MAFLD therapeutics functioning through NLRs.

CONCLUSIONS

NLRs play a significant role in the pathogenesis of MAFLD and its consequences, especially through generation of inflammasomes, such as NLRP3 inflammasomes. Lifestyle changes (exercise, coffee consumption) and therapeutic agents (GLP-1 receptor agonists, sodium-glucose cotransporter-2 inhibitors, obeticholic acid) improve MAFLD and its complications partly through blockade of NLRP3 inflammasome activation. New studies are required to explore these inflammatory pathways fully for the treatment of MAFLD.

The NLRP3 inflammasome: contributions to inflammation-related diseases

The NOD-like receptor protein 3 (NLRP3) inflammasome is a protein complex that regulates innate immune responses by activating caspase-1 and the inflammatory cytokines interleukin (IL)-1β and IL-18. Multiple studies have demonstrated the importance of the NLRP3 inflammasome in the development of immune and inflammation-related diseases, including arthritis, Alzheimer's disease, inflammatory bowel disease, and other autoimmune and autoinflammatory diseases. This review first explains the activation and regulatory mechanism of the NLRP3 inflammasome. Secondly, we focus on the role of the NLRP3 inflammasome in various inflammation-related diseases. Finally, we look forward to new methods for targeting the NLRP3 inflammasome to treat inflammation-related diseases, and provide new ideas for clinical treatment.

Alpinetin inhibits neuroinflammation and neuronal apoptosis via targeting the JAK2/STAT3 signaling pathway in spinal cord injury

BACKGROUND

A growing body of research shows that drug monomers from traditional Chinese herbal medicines have antineuroinflammatory and neuroprotective effects that can significantly improve the recovery of motor function after spinal cord injury (SCI). Here, we explore the role and molecular mechanisms of Alpinetin on activating microglia-mediated neuroinflammation and neuronal apoptosis after SCI.

METHODS

Stimulation of microglia with lipopolysaccharide (LPS) to simulate neuroinflammation models in vitro, the effect of Alpinetin on the release of pro-inflammatory mediators in LPS-induced microglia and its mechanism were detected. In addition, a co-culture system of microglia and neuronal cells was constructed to assess the effect of Alpinetin on activating microglia-mediated neuronal apoptosis. Finally, rat spinal cord injury models were used to study the effects on inflammation, neuronal apoptosis, axonal regeneration, and motor function recovery in Alpinetin.

RESULTS

Alpinetin inhibits microglia-mediated neuroinflammation and activity of the JAK2/STAT3 pathway. Alpinetin can also reverse activated microglia-mediated reactive oxygen species (ROS) production and decrease of mitochondrial membrane potential (MMP) in PC12 neuronal cells. In addition, in vivo Alpinetin significantly inhibits the inflammatory response and neuronal apoptosis, improves axonal regeneration, and recovery of motor function.

CONCLUSION

Alpinetin can be used to treat neurodegenerative diseases and is a novel drug candidate for the treatment of microglia-mediated neuroinflammation.

Total flavone of flowers of Abelmoschus manihot (L.) Medic inhibits the expression of adhesion molecules in primary mesenteric arterial endothelial cells and ameliorates dextran sodium sulphate-induced ulcerative colitis in mice

BACKGROUND

Flowers of Abelmoschus manihot (L.) medic (AM) is a traditional Chinese medicine used to treat chronic nephritis, nephrotic syndrome, diabetic nephropathy, and colonic inflammation.

PURPOSE

This study aimed to explore the influence of the total flavone of AM flowers (TFA) on acute ulcerative colitis (UC) and the potential underlying mechanism.

METHODS

Efficacy of TFA (30, 60, 120 mg/kg) on UC was evaluated in a dextran sodium sulphate (DSS)-induced colonic inflammatory mouse model by analyzing disease activity index (DAI), histopathological score, colon length, and cytokine expression. Expression levels of critical adhesion molecules and nuclear factor kappa B (NF-κB) were examined by qRT-PCR, Western blotting, or immunofluorescence labeling. Myeloperoxidase activity was examined using ELISA. In vitro THP-1 adhesion assay was used to evaluate monocyte adhesion.

RESULTS

TFA significantly reduced DAI score, prevented colon shortening, and ameliorated histological injuries of colons in DSS-treated mice. TFA inhibited the expression of cytokines (IL-1β and TNF-α) and adhesion molecules (ICAM-1, VCAM-1, and MAdCAM-1) in colon tissues of DSS mice. In vitro studies on mesenteric arterial endothelial cells (MAECs) showed that TFA attenuated TNF-α-induced upregulation of ICAM-1, VCAM-1, and MAdCAM-1, as well as THP-1 cell adhesion to MAECs. TFA also suppressed the phosphorylation and nuclear translocation of NF-κB in MAECs.

CONCLUSION

TFA efficaciously ameliorates UC possibly by inhibiting monocyte adhesion through blocking TNF-α-induced NF-κB activation, which in turn suppresses the upregulation of adhesive molecules in colon endothelial cells. Inhibiting the expression of adhesion molecule in MAECs may represent a useful strategy for therapeutic development to treat UC, with TFA being a safe and efficacious therapeutic agent.

Oxyberberine suppressed the carbon tetrachloride-induced liver fibrosis by inhibiting liver inflammation in a sirtuin 3-dependent manner in mice

Previous studies have shown that oxyberberine (OBB), a novel gut microbiota metabolite of berberine, exhibited prominent protective property against acute liver injury and non-alcoholic fatty liver diseases, however, the effect of OBB on liver fibrosis and its potential mechanisms remain largely unknown. This study was aimed to study the effects of OBB on carbon tetrachloride (CCl4)-induced liver fibrosis and tried to clarify the potential mechanisms by focusing on regulating of sirtuin 3 (SIRT3)-mediated liver inflammation. OBB significantly alleviated the liver injury and fibrosis in CCl4-treated C57/BL6 mouse livers. OBB evidently down-regulated the expression of inflammatory factors and reduced the levels of inflammatory factors in CCl4-treated mouse livers. Noteworthy, CCl4-treated decreased the mRNA and protein expression of SIRT3, and treatment with OBB notably increased the expression of SIRT3 both in transcriptional and translational levels in CCl4-treated mice livers. OBB also suppressed the cell viability of TGF-β1-stimulated JS-1 cells and inhibited the protein expression of α-SMA but increased the expression of SIRT3 in stimulated JS-1 cells. Moreover, depletion of SIRT3 weakened the anti-inflammatory effects of OBB in stimulated JS-1 cells. Interestingly, the anti-liver injury and anti-fibrotic effects of OBB could be available in CCl4-treated WT (129S1/SvImJ) mice but were unavailable in CCl4-treated SIRT3 knockout (KO) mice. In addition, the anti-inflammatory effect of OBB was only found in CCl4-treated WT mice but was not in SIRT3 KO mice. Collectively, these findings suggested that OBB suppressed the liver injury and fibrosis through inhibition of liver inflammation in a SIRT3-dependent manner in CCl4-treated mice.

Antioxidant and Anti-Inflammatory Properties of Phytochemicals Found in the Yucca Genus

The Yucca genus encompasses about 50 species native to North America. Species within the Yucca genus have been used in traditional medicine to treat pathologies related to inflammation. Despite its historical use and the popular notion of its antioxidant and anti-inflammatory properties, there is a limited amount of research on this genus. To better understand these properties, this work aimed to analyze phytochemical composition through documentary research. This will provide a better understanding of the molecules and the mechanisms of action that confer such antioxidant and anti-inflammatory properties. About 92 phytochemicals present within the genus have reported antioxidant or anti-inflammatory effects. It has been suggested that the antioxidant and anti-inflammatory properties are mainly generated through its free radical scavenging activity, the inhibition of arachidonic acid metabolism, the decrease in TNF-α (Tumor necrosis factor-α), IL-6 (Interleukin-6), iNOS (Inducible nitric oxide synthase), and IL-1β (Interleukin 1β) concentration, the increase of GPx (Glutathione peroxidase), CAT (Catalase), and SOD (Superoxide dismutase) concentration, and the inhibition of the MAPK (Mitogen-Activated Protein Kinase), and NF-κB (Nuclear factor kappa B), and the activation of the Nrf2 (Nuclear factor erythroid 2-related factor) signaling pathway. These studies provide evidence of its use in traditional medicine against pathologies related to inflammation. However, more models and studies are needed to properly understand the activity of most plants within the genus, its potency, and the feasibility of its use to help manage or treat chronic inflammation.

Fibrosis: Types, Effects, Markers, Mechanisms for Disease Progression, and Its Relation with Oxidative Stress, Immunity, and Inflammation

Most chronic inflammatory illnesses include fibrosis as a pathogenic characteristic. Extracellular matrix (ECM) components build up in excess to cause fibrosis or scarring. The fibrotic process finally results in organ malfunction and death if it is severely progressive. Fibrosis affects nearly all tissues of the body. The fibrosis process is associated with chronic inflammation, metabolic homeostasis, and transforming growth factor-β1 (TGF-β1) signaling, where the balance between the oxidant and antioxidant systems appears to be a key modulator in managing these processes. Virtually every organ system, including the lungs, heart, kidney, and liver, can be affected by fibrosis, which is characterized as an excessive accumulation of connective tissue components. Organ malfunction is frequently caused by fibrotic tissue remodeling, which is also frequently linked to high morbidity and mortality. Up to 45% of all fatalities in the industrialized world are caused by fibrosis, which can damage any organ. Long believed to be persistently progressing and irreversible, fibrosis has now been revealed to be a very dynamic process by preclinical models and clinical studies in a variety of organ systems. The pathways from tissue damage to inflammation, fibrosis, and/or malfunction are the main topics of this review. Furthermore, the fibrosis of different organs with their effects was discussed. Finally, we highlight many of the principal mechanisms of fibrosis. These pathways could be considered as promising targets for the development of potential therapies for a variety of important human diseases.

Amomum subulatum mitigates experimental thoracic radiation-induced lung injury by regulating antioxidant status and inflammatory responses

Radiation-induced lung injury (RILI) is one of the most prominent complications of thoracic radiotherapy for which effective therapy is still lacking. This study investigates the nutraceutical potential of the culinary spice Amomum subulatum in mitigating thoracic radiation-induced pneumonitis (RP) and pulmonary fibrosis (PF). Mouse models of RP and PF were established by whole thorax irradiation at a dose of 25 gray. C57BL/6 mice were administered with 250 mg per kg body weight of methanolic extract of A. subulatum dry fruits (MEAS) for four consecutive weeks and observed for changes in lung tissue antioxidant activities, oxidative stress parameters, and expression of antioxidant, inflammation, and fibrosis-related genes by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and real-time PCR analysis, and histology analysis. MEAS administration reduced radiation-induced oxidative stress by enhancing the expression of Nrf2 and its target genes. Irradiation increased gene expression of inflammatory mediators and lung histology further confirmed the characteristics of RP, which were reduced by MEAS treatment. Immunohistochemistry analysis revealed the potential of MEAS in reducing the radiation-induced elevation of cyclooxygenase 2 expression in the lungs. The late sequel of RILI was manifested as PF, characterized by the elevated expression of pro-fibrotic genes and increased collagen content. However, MEAS administration markedly reduced radiation-induced fibrotic changes in the lungs. These effects might be attributed to the synergistic effect of bioactive polyphenols in MEAS with antioxidant, anti-inflammatory, and anti-fibrotic efficacies. Taken together, this study demonstrates the potential of MEAS in mitigating RILI, suggesting the possible nutraceutical application of A. subulatum against radiation toxicities.

Trained immunity in monocyte/macrophage: Novel mechanism of phytochemicals in the treatment of atherosclerotic cardiovascular disease

Atherosclerosis (AS) is the pathology of atherosclerotic cardiovascular diseases (ASCVD), characterized by persistent chronic inflammation in the vessel wall, in which monocytes/macrophages play a key role. It has been reported that innate immune system cells can assume a persistent proinflammatory state after short stimulation with endogenous atherogenic stimuli. The pathogenesis of AS can be influenced by this persistent hyperactivation of the innate immune system, which is termed trained immunity. Trained immunity has also been implicated as a key pathological mechanism, leading to persistent chronic inflammation in AS. Trained immunity is mediated via epigenetic and metabolic reprogramming and occurs in mature innate immune cells and their bone marrow progenitors. Natural products are promising candidates for novel pharmacological agents that can be used to prevent or treat cardiovascular diseases (CVD). A variety of natural products and agents exhibiting antiatherosclerotic abilities have been reported to potentially interfere with the pharmacological targets of trained immunity. This review describes in as much detail as possible the mechanisms involved in trained immunity and how phytochemicals of this process inhibit AS by affecting trained monocytes/macrophages.

Comprehensive Effect of Carbon Tetrachloride and Reversal of Gandankang Formula in Mice Liver: Involved in Oxidative Stress, Excessive Inflammation, and Intestinal Microflora

To systematically evaluate the effect of Gandankang (GDK) aqueous extract in alleviating acute and chronic liver injury. Forty-one chemical compounds were identified by ultra-high performance liquid chromatography-linear trap quadrupole-orbitrap-tandem mass spectrometry (UHPLC-LTQ-Orbitrap-MS) from GDK. All dosages of GDK and Biphenyl diester (BD) improved CCl4-induced acute and chronic liver injury. GDK curbed liver fibrosis and blocked the NF-κB pathway to effectively inhibit the hepatic inflammatory response. Additionally, GDK treatment reduced the abundance of Phascolarctobacterium, Turicibacter, Clostridium_xlva, Atoprostipes, and Eubacterium, in comparison with those in the CCl4 mice and elevated the abundance of Megamonas and Clostridium_IV as evident from 16S rDNA sequencing. Correlation analysis showed that the abundance of Eubacterium and Phascolarctobacterium was positively correlated with inflammation, fibrosis, and oxidation indexes. This indicates that GDK ameliorates chronic liver injury by mitigating fibrosis and inflammation. Nrf2 pathway is the key target of GDK in inhibiting liver inflammation and ferroptosis. Eubacterium and Phascolarctobacterium played a vital role in attenuating liver fibrosis.

Potential Therapeutic Implication of Herbal Medicine in Mitochondria-Mediated Oxidative Stress-Related Liver Diseases

Mitochondria are double-membrane organelles that play a role in ATP synthesis, calcium homeostasis, oxidation-reduction status, apoptosis, and inflammation. Several human disorders have been linked to mitochondrial dysfunction. It has been found that traditional therapeutic herbs are effective on alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) which are leading causes of liver cirrhosis and hepatocellular carcinoma. The generation of reactive oxygen species (ROS) in response to oxidative stress is caused by mitochondrial dysfunction and is considered critical for treatment. The role of oxidative stress, lipid toxicity, and inflammation in NAFLD are well known. NAFLD is a chronic liver disease that commonly progresses to cirrhosis and chronic liver disease, and people with obesity, insulin resistance, diabetes, hyperlipidemia, and hypertension are at a higher risk of developing NAFLD. NAFLD is associated with a number of pathological factors, including insulin resistance, lipid metabolic dysfunction, oxidative stress, inflammation, apoptosis, and fibrosis. As a result, the improvement in steatosis and inflammation is enough to entice researchers to look into liver disease treatment. However, antioxidant treatment has not been very effective for liver disease. Additionally, it has been suggested that the beneficial effects of herbal medicines on immunity and inflammation are governed by various mechanisms for lipid metabolism and inflammation control. This review provided a summary of research on herbal medicines for the therapeutic implementation of mitochondria-mediated ROS production in liver disease as well as clinical applications through herbal medicine. In addition, the pathophysiology of common liver disorders such as ALD and NAFLD would be investigated in the role that mitochondria play in the process to open new therapeutic avenues in the management of patients with liver disease.

Pharmacological effects of Chinese medicine modulating NLRP3 inflammasomes in fatty liver treatment

Inflammation is a key contributing factor in the pathogenesis of fatty liver diseases (FLD), such as nonalcoholic fatty liver disease (NAFLD) and alcohol-associated liver diseases (ALDs). The NLRP3 inflammasome is widely present in the hepatic parenchymal and non-parenchymal cells, which are assembled and activated by sensing intracellular and extracellular danger signals resulting in the matures of IL-1β/IL-18 and pyroptosis. Moreover, the aberrant activation of the NLRP3 inflammasome is considered the main factor to drives immune outbreaks in relation to hepatic injury, inflammation, steatosis, and fibrosis. Therefore, inhibition of NLRP3 inflammasome may be a promising therapeutic target for FLD. Currently, accumulating evidence has revealed that a number of traditional Chinese medicines (TCM) exert beneficial effects on liver injury via inhibiting the NLRP3 inflammasome activation. Here, we summarized the mechanism of NLRP3 inflammasomes in the progression of FLD, and TCM exerts beneficial effects on FLD via positive modulation of inflammation. We describe that TCM is a promising valuable resource for the prevention and treatment agents against FLD and has the potential to be developed into clinical drugs.

Pharmacological targeting of cGAS/STING-YAP axis suppresses pathological angiogenesis and ameliorates organ fibrosis

Organ fibrosis is accompanied by pathological angiogenesis. Discovering new ways to ameliorate pathological angiogenesis may bypass organ fibrosis. The cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway has been implicated in organ injuries and its activation inhibits endothelial proliferation. Currently, a controversy exists as to whether cGAS/STING activation exacerbates inflammation and tissue injury or mitigates damage, and whether one of these effects predominates under specific context. This study unveiled a new antifibrotic cGAS/STING signaling pathway that suppresses pathological angiogenesis in liver and kidney fibrosis. We showed that cGAS expression was induced in fibrotic liver and kidney, but suppressed in endothelial cells. cGAS genetic deletion promoted liver and kidney fibrosis and pathological angiogenesis, including occurrence of endothelial-to-mesenchymal transition. Meanwhile, cGAS deletion upregulated profibrotic Yes-associated protein (YAP) signaling in endothelial cells, which was evidenced by the attenuation of organ fibrosis in mice specifically lacking endothelial YAP. Pharmacological targeting of cGAS/STING-YAP signaling by both a small-molecule STING agonist, SR-717, and a G protein-coupled receptor (GPCR)-based antagonist that blocks the profibrotic activity of endothelial YAP, attenuated liver and kidney fibrosis. Together, our data support that activation of cGAS/STING signaling mitigates organ fibrosis and suppresses pathological angiogenesis. Further, pharmacological targeting of cGAS/STING-YAP axis exhibits the potential to alleviate liver and kidney fibrosis.

Shibi Tea (Adinandra nitida) and Camellianin A Alleviate CCl4-Induced Liver Injury in C57BL-6J Mice by Attenuation of Oxidative Stress, Inflammation, and Apoptosis

Liver injury is a significant public health issue nowadays. Shibi tea is a non-Camellia tea prepared from the dried leaves of Adinandra nitida, one of the plants with the greatest flavonoid concentration, with Camellianin A (CA) being the major flavonoid. Shibi tea is extensively used in food and medicine and has been found to provide a variety of health advantages. The benefits of Shibi tea and CA in preventing liver injury have not yet been investigated. The aim of this study was to investigate the hepatoprotective effects of extract of Shibi tea (EST) and CA in mice with carbon tetrachloride (CCl₄)-induced acute liver injury. Two different concentrations of EST and CA were given to model mice by gavage for 3 days. Treatment with two concentrations of EST and CA reduced the CCl₄-induced elevation of the liver index, liver histopathological injury score, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Western blotting and immunohistochemical analysis demonstrated that EST and CA regulated the oxidative stress signaling pathway protein levels of nuclear factor E2-related factor 2 (Nrf2)/heme-oxygenase-1 (HO-1), the expression of inflammatory cytokines, the phosphorylated nuclear factor-kappaB p65 (p-NF-κB)/nuclear factor-kappaB p65 (NF-κB) ratio, the phospho-p44/42 mitogen-activated protein kinase (p-MAPK), and the apoptosis-related protein levels of BCL2-associated X (Bax)/B cell leukemia/lymphoma 2 (Bcl2) in the liver. Taken together, EST and CA can protect against CCl₄-induced liver injury by exerting antioxidative stress, anti-inflammation, and anti-apoptosis.

Dual effects of cardamonin/alpinetin and their acrolein adducts on scavenging acrolein and the anti-bacterial activity from Alpinia katsumadai Hayata as a spice in roasted meat

Acrolein (ACR) is frequently produced by the thermal degradation of carbohydrates and amino acids and lipid peroxidation in the thermal processing of food. Long-term exposure to ACR can cause various chronic diseases. Here, we screened two high-temperature-resistant ACR inhibitors, cardamonin (CAR) and alpinetin (ALP), which can interconvert without any loss at 100 °C, and were obtained from Alpinia katsumadai Hayata (AKH). They demonstrated the best activity among the six spices investigated and could scavenge ACR generated in roasted pork by forming adducts. After three ACR adducts were prepared, namely CAR-ACR-1, CAR-ACR-2 and ALP-ACR, quantitative analysis showed that the amount of CAR-ACR-1 generated in lean roasted pork with 2% AKH addition reached the minimal inhibitory concentration against Escherichia coli and Staphylococcus aureus, which was 20 times lower than that of CAR, and the higher the generation of ACR, the stronger its antibacterial activity. These results provided well-defined evidence to promote the application of AKH to ACR inhibitors in food processing.

Alpinetin promotes hair regeneration via activating hair follicle stem cells

Background

Alopecia affects millions of individuals globally, with hair loss becoming more common among young people.  Various traditional Chinese medicines (TCM) have been used clinically for treating alopecia, however, the effective compounds and underlying mechanism are less known. We sought to investigate the effect of Alpinetin (AP), a compound extracted from Fabaceae and Zingiberaceae herbs, in hair regeneration.

Methods

Animal model for hair regeneration was mimicked by depilation in C57BL/6J mice. The mice were then topically treated with 3 mg/ml AP, minoxidil as positive control (PC), or solvent ethanol as vehicle control (VC) on the dorsal skin. Skin color changes which reflected the hair growth stages were monitored and pictured, along with H&E staining and hair shaft length measurement. RNA-seq analysis combined with immunofluorescence staining and qPCR analysis were used for mechanism study. Meanwhile, Gli1^CreERT2; R26R^tdTomato and Lgr5^{EGFP−CreERT2}; R26R^tdTomato transgenic mice were used to monitor the activation and proliferation of Gli1+ and Lgr5+ HFSCs after treatment. Furthermore, the toxicity of AP was tested in keratinocytes and fibroblasts from both human and mouse skin to assess the safety.

Results

When compared to minoxidil-treated and vehicle-treated control mice, topical application of AP promoted anagen initiation and delayed catagen entry, resulting in a longer anagen phase and hair shaft length. Mechanistically, RNA-seq analysis combined with immunofluorescence staining of Lef1 suggested that Lgr5+ HFSCs in lower bulge were activated by AP via Wnt signaling. Other HFSCs, including K15+, Lef1+, and Gli1+ cells, were also promoted into proliferating upon AP treatment. In addition, AP inhibited cleaved caspase 3-dependent apoptosis at the late anagen stage to postpone regression of hair follicles. More importantly, AP showed no cytotoxicity in keratinocytes and fibroblasts from both human and mouse skin.

Conclusion

This study clarified the effect of AP in promoting hair regeneration by activating HFSCs via Wnt signaling. Our findings may contribute to the development of a new generation of pilatory that is more efficient and less cytotoxic for treating alopecia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00619-2.

Alpinetin: A Review of Its Pharmacology and Pharmacokinetics

Flavonoids isolated from medicinal herbs have been utilized as valuable health-care agents due to their virous biological applications. Alpinetin is a natural flavonoid that emerges in many widely used medicinal plants, and has been frequently applied in Chinese patent drugs. Accumulated evidence has demonstrated that alpinetin possesses a broad range of pharmacological activities such as antitumor, antiinflammation, hepatoprotective, cardiovascular protective, lung protective, antibacterial, antiviral, neuroprotective, and other properties through regulating multiple signaling pathways with low systemic toxicity. However, pharmacokinetic studies have documented that alpinetin may have poor oral bioavailability correlated to its extensive glucuronidation. Currently, the reported pharmacological properties and pharmacokinetics profiles of alpinetin are rare to be scientifically reviewed. In this article, we aimed to highlight the mechanisms of action of alpinetin in various diseases to strongly support its curative potentials for prospective clinical applications. We also summarized the pharmacokinetics properties and proposed some viable strategies to convey an appreciable reference for future advances of alpinetin in drug development.

Piperine inhibits AML-12 hepatocyte EMT and LX-2 HSC activation and alleviates mouse liver fibrosis provoked by CCl4: roles in the activation of the Nrf2 cascade and subsequent suppression of the TGF-β1/Smad axis

Piperine (PIP) is an alkaloid derived from peppercorns. Herein, we assessed its effects on hepatocyte EMT and HSC activation in vitro and CCl₄-elicited liver fibrosis in mice. Further experiments were performed to unveil the molecular mechanisms underlying the hepatoprotective activity of PIP. We found that PIP inhibited TGF-β1-provoked AML-12 hepatocyte EMT and LX-2 HSC activation. Mechanistically, in AML-12 and LX-2 cells, PIP evoked Nrf2 nuclear translocation and increased transcriptions of Nrf2-responsive antioxidative genes. These events decreased TGF-β1-induced production of ROS. Moreover, PIP increased the expression of Smad7, suppressed phosphorylation and nuclear translocation of Smad2/3, and decreased the transcriptions of Smad2/3-downstream genes. Knockdown of Nrf2 abrogated the protective activity of PIP against TGF-β1. Modulatory effects of PIP on the TGF-β1/Smad cascade were also crippled, which suggested that activation of Nrf2 played critical roles in the regulatory effects of PIP on TGF-β1/Smad signaling. Experiments in vivo unveiled that PIP ameliorated mouse liver fibrosis provoked by CCl₄. PIP modulated the intrahepatic contents of the markers of EMT and HSC activation. In mouse livers, PIP activated Nrf2 signaling and reduced Smad2/3-dependent gene transcriptions. Our findings collectively suggested PIP as a new chemical entity with the capacity of alleviating liver fibrosis. The activation of the Nrf2 cascade and subsequent suppression of the TGF-β1/Smad axis are implicated in the hepatoprotective activity of PIP.

Up-regulation of Nrf2/P62/Keap1 involves in the anti-fibrotic effect of combination of monoammonium glycyrrhizinate and cysteine hydrochloride induced by CCl4

Combination of monoammonium glycyrrhizinate and cysteine hydrochloride (MG-CH) has been used in the treatment of chronic liver disease for decades, however, its mechanism is still unclear. Our previous studies showed that MG-CH confers the optimal therapeutic effect at the ratio of 2:1 to against acute liver damage. In this study, it was used to investigate the anti-fibrotic effect induced by CCl₄. The results showed that injection of MG-CH produced anti-fibrotic effect ranged from 30 mg/kg to 60 mg/kg, evidenced by decreased the collagens deposition and inhibited the production of hydroxyproline. Mechanism study found that Nrf2/ARE signaling pathway was activated by MG-CH, whereas loss of hepatocytic Nrf2 abolished its anti-fibrotic effect significantly. Furthermore, it was demonstrated that MG-CH is a non-canonical NRF2 inducer, which promoted the autophagy activity and release the Nrf2 from keap 1 by promoting the phosphorylation of p62 at Ser351. Knockdown of p62 abolished the enhancement of nuclear accumulation of Nrf2 by MG-CH. All of these results suggested that up-regulation of Nrf2/P62/Keap1 involves in the anti-fibrotic effect of MG-CH, which provide a rational explanation for the usage of MG-CH in the treatment of fibrosis.

Propolis and Its Gastroprotective Effects on NSAID-Induced Gastric Ulcer Disease: A Systematic Review

Gastric ulcer disease induced by the consumption of NSAIDs is a major public health problem. The therapy used for its treatment causes adverse effects in the patient. Propolis is a natural product that has been used for the treatments of different diseases around the world. Nevertheless, there is little information about the activity of propolis in gastric ulcers caused by treatment with NSAIDs. Therefore, this review evaluates and compares the gastroprotective potential of propolis and its function against NSAID-induced gastric ulcers, for which a systematic search was carried out in the PubMed and ScienceDirect databases. The main criteria were articles that report the gastroprotective activity of propolis against the damage produced by NSAIDs in the gastric mucosa. Gastroprotection was related to the antioxidant, antisecretory, and cytoprotective effects, as well as the phenolic compounds present in the chemical composition of propolis. However, most of the studies used different doses of NSAIDs and propolis and evaluated different parameters. Propolis has proven to be a good alternative for the treatment of gastric ulcer disease. However, future studies should be carried out to identify the compounds responsible for these effects and to determine their potential use in people.