Gingerenone A Alleviates Ferroptosis in Secondary Liver Injury in Colitis Mice via Activating Nrf2-Gpx4 Signaling Pathway

Dictamnine alleviates DSS-induced colitis mice by inhibiting ferroptosis of enterocytes via activating Nrf2-Gpx4 signaling pathway

BACKGROUND

The treatment of ulcerative colitis (UC) remains a huge challenge worldwide. Dictamnine is a natural product derived from Dictamnus dasycarpus Turcz. root bark and possesses multi-pharmacological properties, including anti-inflammation effects. However, its protective effect on UC and its underlying mechanisms are unknown.

PURPOSE

Here we explored the protective effect and underlying mechanism of dictamnine against dextran sulfate sodium (DSS)-induced colitis in mice.

METHODS

The experimental colitis was established by adding 3% DSS on drinking water of mice and the effects of dictamnine (10, 20, 40 mg/kg, p.o, once a day by 10 days) in colon tissues was analyzed. NCM460 cell was induced by RSL3 to detect the effect of dictamnine on ferroptosis and the underlying mechanism. Pathological damage was determined by H&E. Indicators related to intestinal permeability were detected by FITC and immunofluorescence. Cytokines levels (TNF-α、IL-1β and IL-6), antioxidant enzymes activities (MDA and GSH), the level of Fe2+ Cytokines levels and Gpx4 activity were detected by ELISA. Finally, the activation of nuclear factor erythroid 2-like 2 (Nrf2) was detected to explore the mechanism.

RESULTS

The results indicated that dictamnine significantly attenuated DSS-induced colon pathological damage, intestinal barrier, cytokines levels, and increased the antioxidant enzymes activities. Moreover, dictamnine attenuated ferroptosis in DSS-induced colon injury and upregulated Gpx4 expression in DSS-induced mice. Mechanistic experiments revealed that dictamnine activated Nrf2 in mice.

CONCLUSION

Taken together, this study evaluates that dictamnine alleviates DSS-induced colitis mice by inhibiting ferroptosis of enterocytes and its protective effects are associated with activating the Nrf2-Gpx4 signaling pathway.

Ferroptosis as a key player in the pathogenesis and intervention therapy in liver injury: focusing on drug-induced hepatotoxicity

Globally, drug-induced hepatotoxicity or drug-induced liver injury (DILI) is a serious clinical concern. Knowing the processes and patterns of cell death is essential for finding new therapeutic targets since there are not many alternatives to therapy for severe liver lesions. Excessive lipid peroxidation is a hallmark of ferroptosis, an iron-reliant non-apoptotic cell death linked to various liver pathologies. When iron is pathogenic, concomitant inflammation may exacerbate iron-mediated liver injury, and the hepatocyte necrosis that results is a key element in the fibrogenic response. The idea that dysregulated metabolic pathways and compromised iron homeostasis contribute to the development of liver injury by ferroptosis is being supported by new data. Various ferroptosis-linked genes and pathways have been linked to liver injury, although the molecular processes behind ferroptosis's pathogenicity are not well known. Here, we delve into the features of ferroptosis, the processes governing ferroptosis, and our current knowledge of iron metabolism. We also provide an overview of ferroptosis's involvement in the pathophysiology of liver injury, particularly DILI. Lastly, the therapeutic possibilities of ferroptosis targeting for liver injury management have been provided. Natural products, nanoparticles (NPs), mesenchymal stem cell (MSC), and their exosomes have attracted increasing attention among such therapeutics.

Total Sanghuangporus vaninii extract inhibits hepatocyte ferroptosis and intestinal microbiota disturbance to attenuate liver fibrosis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Sanghuangporus, the dried fruiting body of Sanghuangporus vaninii (Ljub) L.W.Zhou et Y.C.Dai. As the main species of Sanghuang, it has been well-known and used commonly as a traditional medicinal and edible macrofungi for thousands of years in many countries, including China, Korea and Japan. Although it has good hepatoprotective activity, its potential efficacy and mechanism on liver fibrosis remain elusive.

AIM OF THE STUDY

Total Sanghuangporus vaninii extract (TSH) was prepared by ethanol extraction to investigate its chemical components and to conduct an initial assessment of its efficacy and underlying mechanism in a murine model of liver fibrosis.

MATERIALS AND METHODS

The chemical components of TSH were initially analyzed by UHPLC-Q-Orbitrap HRMS. To elucidate the effects of TSH, an in vivo model of fibrosis was established in mice using carbon tetrachloride (CCl4), followed by assessments of serum liver function and histopathological analysis. Besides, indicators related to liver fibrosis, hepatic stellate cells (HSCs) activation, inflammation response and ferroptosis related indicators were detected by western blotting, immunohistochemistry and real-time quantitative PCR (RT-qPCR) analysis. Additionally, the 16S rDNA sequencing and untargeted metabolomics analysis of intestinal microbiota were employed to investigating the role of TSH in gut microbiome. In vitro, the human hepatocyte line L02 was stimulated with erastin and treated with or without TSH to elucidate its underlying mechanism.

RESULTS

The administration of TSH significantly improved serum indicators of liver injury in CCl4-induced fibrosis mice, reduced HSCs activation and collagen deposition, while inhibiting the expressions of transforming growth factor-β1(TGF-β1)/Smad signaling pathway. Notably, TSH treatment attenuated hepatocyte ferroptosis and lipid peroxidation both in vivo and in vitro, as evidenced by a marked decrease in liver iron and malondialdehyde (MDA) contents. In particular, TSH was demonstrated to activate the nuclear factor erythroid 2-related factor 2 (Nrf2)-glutathione peroxidase 4 (GPX4) signaling pathway, thereby protecting hepatocytes from ferroptosis with a particular enhancement of Nrf2 nuclear transcription. Furthermore, TSH influenced gut microbiota composition and ameliorated intestinal metabolic disorders. The increased abundance of Parasutterella and Olsenellas due to TSH treatment was significantly positively correlated with elevated phosphatidylcholines involved in linoleic acid metabolism, and negatively correlated with the reduction of fatty acyls. And the enrichment of intestinal linoleic acid metabolism presented a negative correlation in liver fibrosis biomarkers.

CONCLUSIONS

Our findings indicate that the TSH treatment exerts a significantly protective effect on CCl4-induced mice by ameliorating hepatic injury and ferroptosis damage, inhibiting HSCs activation and collagen deposition, and remodeling gut microbiota homeostasis and metabolic imbalance. Notably, TSH attenuated hepatocyte ferroptosis in liver fibrosis and exhibited upregulation of the Nrf2-GPX4 signaling pathway. Furthermore, TSH could enrich the abundance of Parasutterella and Olsenellas, which may contribute to intestinal linoleic acid metabolism, thereby contributing to the reduction of liver fibrosis damage. Our study provides more effective and unreported evidence of TSH in anti-fibrosis activity.

Phenethyl isothiocyanate ameliorates liver injuries secondary to inflammatory bowel disease

Inflammatory bowel disease (IBD) is often accompanied by secondary liver injury which further evolves into various hepatobiliary disorders. The pathogenesis of secondary liver injury involves many different mechanisms including inflammation, pyroptosis, oxidative stress, and heat shock response. Here, we tested the effect of administration of phenethyl isothiocyanate (PEITC) on secondary liver injury in DSS-induced IBD mice. PEITC supplementation reversed liver injury as determined by hepatic injury-related parameters and histopathological examinations. Severe hepatic inflammation with IBD, evidenced by ubiquitously distributed activated macrophages, increased secretion of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6), enhanced expression of inflammation-related proteins (iNOS and COX-2), and augmented activation of the TLR4/NF-κB signaling pathway, was inhibited by PEITC treatment. PEITC also prevented IBD-induced increases in pyroptosis and oxidative stress in the liver. In addition, impairments of hepatic heat shock response elicited by IBD were restored by PEITC treatment. Taken together, these results suggested that PEITC may be effective as a therapeutic reagent to attenuate secondary liver injury caused by IBD.

Monotropein inhibits epithelial-mesenchymal transition in chronic colitis via the mTOR/P70S6K pathway

Introduction

Patients with chronic colitis are at risk of developing intestinal fibrosis through epithelial-mesenchymal transition (EMT). Monotropein (MON) is the main active ingredient in the traditional Chinese medicine Morinda officinalis How. It has been reported that monotropein can improve ulcerative colitis, but the mechanism remains unclear. However, whether monotropein can improve chronic colitis-associated intestinal fibrosis remains unknown. The study aimed to investigate the effect of monotropein on EMT in chronic colitis and its underlying mechanism.

Methods

The mice chronic colitis model was induced by dextran sodium sulfate (DSS). Cytokines were detected by ELISA. Concentrations of fluorescein isothiocyanate dextran (FITC-Dextran) in serum were detected using a fluorescein microplate analyzer. Intestinal tight junction proteins were detected by immunofluorescence. EMT marker proteins were detected by immunohistochemistry. Transforming growth factor-β1 (TGF-β1) was used to induce EMT in IEC-6 cells. Western blot, real-time quantitative PCR, and immunofluorescence were used to test the inhibitory effect of monotropein on the development of EMT and explore its mechanism.

Results

Results showed that monotropein significantly improved colonic injury and inhibited the expression of colonic tissue EMT marker protein. In addition, molecular docking and molecular dynamics (MD) simulation, cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS) assay validated monotropein targeting of mTOR. Monotropein inhibited TGF-β1-induced EMT in IEC-6 cells, inhibited the phosphorylation of mTOR and its downstream proteins, and increased the autophagy activity in chronic colitis mice and IEC-6 cells.

Discussion

The study indicates that monotropein inhibits the development of EMT in DSS-induced chronic colitis mice and TGF-β1-induced IEC-6 cells. Its inhibitory effect on EMT is associated with the mTOR/P70S6K pathway.

Vitexin alleviates MNNG-induced chronic atrophic gastritis via inhibiting NLRP3 inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

The dried fruit of Crataegus pinnatifida Bunge (Hawthorn in Chinese) is a traditional medicine used in China, Japan and Korea for thousands of years. Hawthorn is documented in the Chinese Pharmacopoeia, as a folk medicine that is used to eliminate food, strengthen the stomach, move qi and dissipate blood stasis, treat stagnation of meat and food, gastric distention and fullness, and has anti-inflammatory effects. Vitexin, a flavonoid glycoside, is an important biologically active compound derived from Hawthorn, with significant antioxidant and anti-inflammatory properties. The pharmacological effects of Hawthorn are highly correlated with the antioxidant and anti-inflammatory effects of vitexin.

AIM OF THE STUDY

The aim of the present study was to investigate the effect of vitexin on the alleviation of chronic atrophic gastritis (CAG) induced by 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) in a rat model, as well as to elucidate the underlying mechanisms involved.

MATERIALS AND METHODS

CAG was administered at a concentration of 170 μg/mL MNNG in the drinking water of rats, and the effects of vitexin (30 mg/kg, once daily for 6 weeks) on gastric tissues were subsequently analyzed. Pathological damage was assessed using H&E and AB-PAS staining. Gastrointestinal hormone levels, specifically motilin (MTL) and gastrin (GAS), were quantified using biochemical index determination kits. To evaluate the levels of cytokines, specifically IL-1β and IL-18, in gastric tissue, an enzyme-linked immunosorbent assay (ELISA) was performed. Additionally, to investigate the effects of vitexin on the NLRP3 inflammasome, GES-1 cells were subjected to treatment with lipopolysaccharide (LPS) and adenosine triphosphate (ATP). The targeting of NLRP3 by vitexin was assessed in vitro using CESTA, DARTS, and a synthesized biotin-labeled vitexin probe (biotin-vitexin) in conjunction with dual immunofluorescence. RT-PCR, Western blotting and immunofluorescence were used to evaluate the ameliorative effect of oysterin on LPS + ATP-induced GES-1 cells in vitro.

RESULTS

Administration of vitexin significantly alleviated the symptoms of chronic atrophic gastritis (CAG) by reducing weight loss and minimizing gastric tissue damage. Treatment with vitexin in CAG rats effectively reduces the production of pro-inflammatory cytokines. Furthermore, vitexin attenuated the activation of the NLRP3 inflammasome in CAG induced by MNNG. Mechanistic experiments showed that NLRP3 is a direct cellular target of vitexin, while vitexin inhibited rat NLRP3 inflammasome.

CONCLUSION

Vitexin mitigates MNNG-induced CAG, and its protective effect is linked to the inhibition of NLRP3 inflammasome activation.

Tomatidine Alleviates Intervertebral Disc Degeneration by Activating the Nrf2/HO-1/GPX4 Signaling Pathway

Purpose

Intervertebral disc degeneration (IDD) is a leading cause of low back pain, and developing new molecular drugs and targets for IDD is a new direction for future treatment strategies. The aim of this study is to investigate the effects and mechanisms of tomatidine in ameliorating lumbar IDD.

Methods

Nucleus pulposus cells (NPCs) exposed to lipopolysaccharides were used as an in vitro model to investigate changes in the expression of extracellular matrix components and associated signaling pathway molecules. A lumbar instability model was used to simulate IDD. Tomatidine (Td) was then administered intraperitoneally, and its effects were evaluated through histopathological analysis.

Results

In vitro, Td significantly promoted ECM anabolism, inhibited ECM catabolism, and reduced oxidative stress and ferroptosis in LPS-stimulated NPCs. When Nrf2 expression was inhibited, oxidative stress and ferroptosis were exacerbated, and the protective effects of Td on NPCs were lost, suggesting the Nrf2/HO-1/GPX4 axis is critical for the therapeutic effects of Td. In vivo, histopathological analysis demonstrated that Td ameliorated IDD in a murine model.

Conclusion

Td alleviates IDD in vitro and in vivo by activating the Nrf2/HO-1/GPX4 pathway to inhibit ferroptosis in NPCs. This mechanism suggests Td is a promising candidate for IDD treatment.

Radish red attenuates chronic kidney disease in obese mice through repressing oxidative stress and ferroptosis via Nrf2 signaling improvement

Chronic kidney disease (CKD) presents a significant public health concern, with obesity being a prominent contributing factor to kidney disorders by inducing oxidative stress, lipotoxicity, and tubular cell injury. Natural anthocyanins extracted from red radishes (Raphanus sativus L.) exert antioxidant and anti-apoptotic functions. This study aims to employ a novel natural pigment anthocyanin, referred to as radish red (RR) isolated from red radishes, to alleviate obesity-related metabolic disturbances and kidney impairment in a CKD mouse model induced by high-fat and high-fructose diets (HFFD). The in vitro study initially demonstrated that RR treatment significantly mitigated the palmitate acid (PA)-induced injury and cytotoxicity in human tubular epithelial HK2 cells. Subsequently, RR supplementation notably improved obesity and associated metabolic dysfunctions in mice caused by HFFD. Abnormal renal function indices including serum creatinine, blood urea nitrogen (BUN), uric acid (UA), urine protein, albuminuria and urine albumin-to-creatinine ratio (UACR) were detected in HFFD-fed mice, which were effectively alleviated by RR treatment. Histologically, renal tubular cell injury, lipid deposition, tubular dilatation, and renal fibrosis induced by HFFD were markedly improved after RR administration in mice. Furthermore, RR treatment significantly alleviated oxidative stress in HFFD-fed mice, as evidenced by the decreased renal reactive oxygen species (ROS) production, 4-HNE, and NOX4 expression levels. Anti-oxidants such as superoxide dismutase-1 (SOD1), NAD (P) H: quinone oxidoreductase (NQO1), heme oxygenase-1 (HO-1) and glutamate cysteine ligase (GCLC) were highly upregulated in kidney of HFFD-fed mice with RR consumption through improving NFE2-related factor 2 (Nrf2) signaling activation. Furthermore, ferroptosis was identified in the kidneys of HFFD-fed mice, evidenced by the elevated levels of malondialdehyde (MDA), iron content, and lipid peroxidation, along with the decreased expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11). These occurrences were significantly mitigated following RR treatment. Mechanistically, we further discovered that the suppressive effects of RR in restricting oxidative stress, ferroptosis, lipid accumulation, and injury of tubular epithelial cells induced by PA were significantly counteracted by Nrf2 knockdown. Collectively, our results demonstrated that dietary supplementation with RR could potentially serve as an efficacious therapeutic modality for the management of obesity-related CKD progression by enhancing Nrf2 activation to impede oxidative stress and ferroptosis.

Gingerenone A induces ferroptosis in colorectal cancer via targeting suppression of SLC7A11 signaling pathway

BACKGROUND

Colorectal cancer (CRC) is one of the most common and fatal diseases, yet effective therapeutic drugs are lacking in clinical settings. Gingerenone A (GA) is an active compound derived from ginger, has demonstrated anti-tumor properties. However, the efficacy of GA against CRC and its primary mechanism of action remain unclear.

MATERIALS AND METHODS

MTT assay and colony formation assay were employed to evaluate cell viability. Transwell assays were utilized to assess the migratory and invasive capabilities of the cells. The effects of GA on ferroptosis related proteins were analyzed using Western blot. Levels of glutathione (GSH), malondialdehyde (MDA), Fe2+, and 4-hydroxynonenal (4-HNE) levels were measured with a biochemical index determination kit. Cellular reactive oxygen species (ROS) were quantified using flow cytometry. CETSA, pull-down, and co-immunoprecipitation (Co-IP) assays confirmed the interactions between GA and SLC7A11, as well as the ubiquitination promoted by SLC7A11. A xenograft mouse model was employed to validate the anticancer effect of GA in vivo.

RESULTS

We observed that GA significantly suppressed proliferation in human CRC cells. Additionally, GA treatment inhibited the migration, invasion, and colony formation of CRC cells. Subsequently, through the use of specific inhibitors, we discovered that the suppression of CRC cells by GA was dependent on ferroptosis rather than autophagy or apoptosis. Previous research has demonstrated that GA treatment significantly triggers ferroptosis. Mechanistically, GA treatment promotes the degradation of the SLC7A11 protein, which plays a crucial role in ferroptosis. Notably, the knockdown of SLC7A11 abolished the detrimental effects of GA on the proliferation of CRC cells and reversed GA-induced ferroptosis in CRC cells both in vivo and in vitro. Further research has shown that GA can directly bind to the SLC7A11 protein and promote its ubiquitination.

CONCLUSION

Our research provides compelling evidence that GA may serve as a potential agent for suppressing the progression of CRC by inducing ferroptosis and promoting the ubiquitination and degradation of SLC7A11.

Discovery of vitexin as a novel VDR agonist that mitigates the transition from chronic intestinal inflammation to colorectal cancer

Colitis-associated colorectal cancer (CAC) frequently develops in patients with inflammatory bowel disease (IBD) who have been exposed to a prolonged state of chronic inflammation. The investigation of pharmacological agents and their mechanisms to prevent precancerous lesions and inhibit their progression remains a significant focus and challenge in CAC research. Previous studies have demonstrated that vitexin effectively mitigates CAC, however, its precise mechanism of action warrants further exploration. This study reveals that the absence of the Vitamin D receptor (VDR) accelerates the progression from chronic colitis to colorectal cancer. Our findings indicate that vitexin can specifically target the VDR protein, facilitating its translocation into the cell nucleus to exert transcriptional activity. Additionally, through a co-culture model of macrophages and cancer cells, we observed that vitexin promotes the polarization of macrophages towards the M1 phenotype, a process that is dependent on VDR. Furthermore, ChIP-seq analysis revealed that vitexin regulates the transcriptional activation of phenazine biosynthesis-like domain protein (PBLD) via VDR. ChIP assays and dual luciferase reporter assays were employed to identify the functional PBLD regulatory region, confirming that the VDR/PBLD pathway is critical for vitexin-mediated regulation of macrophage polarization. Finally, in a mouse model with myeloid VDR gene knockout, we found that the protective effects of vitexin were abolished in mid-stage CAC. In summary, our study establishes that vitexin targets VDR and modulates macrophage polarization through the VDR/PBLD pathway, thereby alleviating the transition from chronic colitis to colorectal cancer.

Vitamin E and GPX4 cooperatively protect treg cells from ferroptosis and alleviate intestinal inflammatory damage in necrotizing enterocolitis

BACKGROUND

The notable decline in the number of Tregs within Necrotizing enterocolitis (NEC) intestinal tissues，contribute to excessive inflammation and necrosis, yet the precise underlying factors remain enigmatic. Ferroptosis, a novel cell death stemming from a disrupted lipid redox metabolism, is the focus of this investigation. Specifically, this study delves into the ferroptosis of Treg cells in the context of NEC and observes the protective effects exerted by vitamin E intervention, which aims to mitigate ferroptosis of Treg cells.

METHODS

To investigate the reduction of Treg cells in NEC intestine, we analyzed its association with ferroptosis from multiple angles. We constructed a mouse with a specific knockout of Gpx4 in Treg cells, aiming to examine the impact of Treg cell ferroptosis on NEC intestinal injury and localized inflammation. Ultimately, we employed vitamin E treatment to mitigate ferroptosis in NEC intestine's Treg cells, monitoring the subsequent amelioration in intestinal inflammatory damage.

RESULTS

The diminution of Treg cells in NEC is attributed to ferroptosis stemming from diminished GPX4 expression. Gpx4-deficient Treg cells exhibit impaired immunosuppressive function and are susceptible to ferroptosis. This ferroptosis of Treg cells exacerbates intestinal damage and inflammatory response in NEC. Notably, Vitamin E can inhibit the ferroptosis of Treg cells, subsequently alleviating intestinal damage and inflammation in NEC. Additionally, Vitamin E bolsters the anti-lipid peroxidation capability of Treg cells by upregulating the expression of GPX4.

CONCLUSION

In the context of NEC, the ferroptosis of Treg cells represents a significant factor contributing to intestinal tissue damage and an exaggerated inflammatory response. GPX4 is pivotal for the viability and functionality of Treg cells. Vitamin E exhibits the capability to mitigate the ferroptosis of Treg cells, thereby enhancing their number and function, which plays a crucial role in mitigating intestinal tissue damage and inflammatory response in NEC.

Mechanism of Action and Therapeutic Implications of Nrf2/HO-1 in Inflammatory Bowel Disease

Oxidative stress (OS) is a key factor in the generation of various pathophysiological conditions. Nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) is a major transcriptional regulator of antioxidant reactions. Heme oxygenase-1 (HO-1), a gene regulated by Nrf2, is one of the most critical cytoprotective molecules. In recent years, Nrf2/HO-1 has received widespread attention as a major regulatory pathway for intracellular defense against oxidative stress. It is considered as a potential target for the treatment of inflammatory bowel disease (IBD). This review highlights the mechanism of action and therapeutic significance of Nrf2/HO-1 in IBD and IBD complications (intestinal fibrosis and colorectal cancer (CRC)), as well as the potential of phytochemicals targeting Nrf2/HO-1 in the treatment of IBD. The results suggest that the therapeutic effects of Nrf2/HO-1 on IBD mainly involve the following aspects: (1) Controlling of oxidative stress to reduce intestinal inflammation and injury; (2) Regulation of intestinal flora to repair the intestinal mucosal barrier; and (3) Prevention of ferroptosis in intestinal epithelial cells. However, due to the complex role of Nrf2/HO-1, a more nuanced understanding of the exact mechanisms involved in Nrf2/HO-1 is the way forward for the treatment of IBD in the future.

Ferroptosis: a new mechanism of traditional Chinese medicine for treating ulcerative colitis

Ulcerative colitis (UC), a subtype of inflammatory bowel disease, manifests with symptoms such as abdominal pain, diarrhea, and mucopurulent, bloody stools. The pathogenesis of UC is not fully understood. At present, the incidence of UC has increased significantly around the world. Conventional therapeutic arsenals are relatively limited, with often poor efficacy and many adverse effects. In contrast, traditional Chinese medicine (TCM) holds promise due to their notable effectiveness, reduced recurrence rates, and minimal side effects. In recent years, significant progress has been made in the basic research on TCM for UC treatment. It has been found that the inhibition of ferroptosis through the intervention of TCM can significantly promote intestinal mucosal healing and reverse UC. The mechanism of action involves multiple targets and pathways.

Aim of the review

This review summarizes the experimental studies on the targeted regulation of ferroptosis by TCM and its impact on UC in recent years, aiming to provide theoretical basis for the prevention, treatment, and further drug development for UC.

Results

Ferroptosis disrupts antioxidant mechanisms in intestinal epithelial cells, damages the intestinal mucosa, and participates in the pathological process of UC. TCM acts on various pathways such as Nrf2/HO-1 and GSH/GPX4, blocking the pathological progression of ferroptosis in intestinal epithelial cells, inhibiting pathological damage to the intestinal mucosa, and thereby alleviating UC.

Conclusion

The diverse array of TCM single herbs, extracts and herbal formulas facilitates selective and innovative research and development of new TCM methods for targeting UC treatment. Although progress has been made in studying TCM compound formulas, single herbs, and extracts, there are still many issues in clinical and basic experimental designs, necessitating further in-depth scientific exploration and research.

Esculin inhibits hepatic stellate cell activation and CCl4-induced liver fibrosis by activating the Nrf2/GPX4 signaling pathway

BACKGROUND

Liver fibrosis (LF) is a pathological process of the liver that threatens human health. Currently, effective treatments are still lacking. Esculin, a prominent constituent found in the Fraxinus rhynchophylla. (bark), Aesculus hippocastanum. (bark), and Cichorium intybus. (herb), has been shown to possess significant anti-inflammatory, antioxidant, and antibacterial properties. However, to date, there have been no studies investigating its potential efficacy in the treatment of LF.

OBJECTIVE

The study aims to investigate the therapeutic effect of esculin on LF and elucidate its potential molecular mechanism.

METHODS

Carbon tetrachloride (CCl4) was injected intraperitoneally to induce LF in mice, and transforming growth factor β1 (TGF-β1) was injected to induce LX-2 cells to investigate the improvement effect of esculin on LF. Kit, histopathological staining, immunohistochemistry (IHC), immunofluorescence (IF), polymerase chain reaction (PCR), and western blot (WB) were used to detect the expression of fiber markers and nuclear factor erythroid 2-related factor 2 (Nrf2)/glutathione peroxidase 4 (GPX4) signaling pathway in liver tissue and LX-2 cells. Finally, molecular docking, cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS) were used to verify the targeting between Nrf2 and esculin.

RESULTS

Esculin significantly inhibited CCl4-induced hepatic fibrosis and inflammation in mice. This was evidenced by the improvement of liver function indexes, fibrosis indicators, and histopathology. Additionally, esculin treatment prominently reduced the levels of pro-inflammatory factors, oxidative stress, and liver Fe2+ in CCl4-induced mice. In vitro studies also showed that esculin treatment significantly inhibited TGF-β1-induced LX-2 cell activation and decreased alpha-smooth muscle actin (α-SMA) and collagen I expression. Mechanism experiments proved that esculin can activate the Nrf2/GPX4 signaling pathway and inhibit liver ferroptosis. However, when LX-2 cells were treated with the Nrf2 inhibitor (ML385), the therapeutic effect of esculin significantly decreased.

CONCLUSION

This study is the first to demonstrate that esculin is a potential natural active ingredient in the treatment of LF, which can inhibit the activation of hepatic stellate cells (HSC) and improve LF. Its therapeutic effect is related to the activation of the Nrf2/GPX4 signaling pathway.

Ferroptosis in ulcerative colitis: Potential mechanisms and promising therapeutic targets

Ulcerative colitis (UC) is a complex immune-mediated chronic inflammatory bowel disease. It is mainly characterized by diffuse inflammation of the colonic and rectal mucosa with barrier function impairment. Identifying new biomarkers for the development of more effective UC therapies remains a pressing task for current research. Ferroptosis is a newly identified form of regulated cell death characterized by iron-dependent lipid peroxidation. As research deepens, ferroptosis has been demonstrated to be involved in the pathological processes of numerous diseases. A growing body of evidence suggests that the pathogenesis of UC is associated with ferroptosis, and the regulation of ferroptosis provides new opportunities for UC treatment. However, the specific mechanisms by which ferroptosis participates in the development of UC remain to be more fully and thoroughly investigated. Therefore, in this review, we focus on the research advances in the mechanism of ferroptosis in recent years and describe the potential role of ferroptosis in the pathogenesis of UC. In addition, we explore the underlying role of the crosslinked pathway between ferroptosis and other mechanisms such as macrophages, neutrophils, autophagy, endoplasmic reticulum stress, and gut microbiota in UC. Finally, we also summarize the potential compounds that may act as ferroptosis inhibitors in UC in the future.

Investigation of the material basis and mechanism of Lizhong decoction in ameliorating ulcerative colitis based on spectrum-effect relationship and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Lizhong decoction (LZD), a classical herbal prescription recorded by Zhang Zhongjing in Treatise on Febrile and Miscellaneous Diseases, has been extensively used to treat ulcerative colitis (UC) in clinical practice for thousands of years. However, its material basis and underlying mechanism are not yet clear.

AIM OF THE STUDY

This study aims to explore the material basis and potential mechanism of LZD against UC based on the spectrum-effect relationship and network pharmacology.

MATERIALS AND METHODS

First, LZD was extracted by a systematic solvent extraction method into four parts. Ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) technique was used to identify the compounds from different polar parts, and dextran sulfate sodium (DSS)-induced colitis model was used to evaluate the efficacy of each fraction. Then, the spectrum-effect analyses of compounds and efficacy indicators were established via grey relational analysis (GRA), bivariate correlation analysis (BCA) and partial least squares regression (PLSR). Finally, the potential mechanism of LZD for UC therapy was explored by network pharmacology, and the results were further verified by molecular docking and reverse transcription quantitative polymerase chain reaction (RT-qPCR).

RESULTS

66 chemical components of LZD were identified by UPLC-Q-TOF-MS/MS technology. The pharmacodynamic results showed that extraction parts of LZD had different therapeutic effects on UC, among which ethyl acetate and n-butanol extracts had significant anti-colitis effects, which might be the main effective fractions of LZD. Furthermore, the spectrum-effect analyses indicated that 21 active ingredients such as liquiritin apioside, neolicuroside, formononetin, ginsenoside Rg1, 6-gingesulfonic acid, licoricesaponin A3, liquiritin, glycyrrhizic acid were the main material basis for LZD improving UC. Based on the above results, network pharmacology suggested that the amelioration of LZD on UC might be closely related to the PI3K-Akt signaling pathway. Additionally, molecular docking technology and RT-qPCR further verified that LZD could markedly inhibit the PI3K-Akt signaling pathway.

CONCLUSION

Overall, our study first identified the chemical compositions of LZD by using UPLC-Q-TOF-MS/MS. Furthermore, the material basis and potential mechanism of LZD in improving UC were comprehensively elucidated via spectrum-effect relationships, network pharmacology, molecular docking and experimental verification. The proposed strategy provided a systematic approach for exploring how herbal medicines worked. More importantly, it laid the solid foundation for further clinical application and rational development of LZD.

Ginsenoside Rg1 Alleviates Ulcerative Colitis in Obese Mice by Regulating the Gut Microbiota-Lipid Metabolism-Th1/Th2/Th17 Cells Axis

Ginsenoside Rg1 (G-Rg1) has various pharmacological properties including antiobesity, immunomodulatory, and anti-inflammatory effects. This study aimed to explore the therapeutic effects and underlying mechanisms of G-Rg1 on colitis complicated by obesity. The results indicate that G-Rg1 effectively alleviates colitis in obese mice and improves serum lipid levels and liver function. Importantly, G-Rg1 improved the composition of gut microbiota in obese mice with colitis, with increases in alpha diversity indexes Sobs, Ace, and Chao, a significant down-regulation of the relative abundance of Romboutsia, and a significant up-regulation of Rikenellaceae_RC9_gut_group, Lachnospiraceae_NK4A136_group, Enterorhabdus, Desulfovibrio, and Alistipes. Meanwhile, G-Rg1 improved lipid metabolism in the colonic contents of obese mice with colitis. Additionally, G-Rg1 significantly reduced the percentages of helper T (Th)1, Th17, central memory T (TCM), and effector memory T (TEM) cells in obese mice with colitis while significantly increasing Naïve T and Th2 cells. In conclusion, G-Rg1 could be a promising therapeutic option for alleviating obesity complicated by colitis through regulation of the gut microbiota and lipid metabolism as well as Th1/Th2/Th17 cell differentiation.

Metabolic dysfunction-associated steatotic liver disease: ferroptosis related mechanisms and potential drugs

Metabolic dysfunction-associated steatotic liver disease (MASLD) is considered a "multisystem" disease that simultaneously suffers from metabolic diseases and hepatic steatosis. Some may develop into liver fibrosis, cirrhosis, and even hepatocellular carcinoma. Given the close connection between metabolic diseases and fatty liver, it is urgent to identify drugs that can control metabolic diseases and fatty liver as a whole and delay disease progression. Ferroptosis, characterized by iron overload and lipid peroxidation resulting from abnormal iron metabolism, is a programmed cell death mechanism. It is an important pathogenic mechanism in metabolic diseases or fatty liver, and may become a key direction for improving MASLD. In this article, we have summarized the physiological and pathological mechanisms of iron metabolism and ferroptosis, as well as the connections established between metabolic diseases and fatty liver through ferroptosis. We have also summarized MASLD therapeutic drugs and potential active substances targeting ferroptosis, in order to provide readers with new insights. At the same time, in future clinical trials involving subjects with MASLD (especially with the intervention of the therapeutic drugs), the detection of serum iron metabolism levels and ferroptosis markers in patients should be increased to further explore the efficacy of potential drugs on ferroptosis.

Alterations in skeletal muscle abundance of protein turnover, stress, and antioxidant proteins during the periparturient period in dairy cows fed ethyl-cellulose rumen-protected methionine

Skeletal muscle turnover helps support the physiological needs of dairy cows during the transition into lactation. We evaluated effects of feeding ethyl-cellulose rumen-protected methionine (RPM) during the periparturient period on abundance of proteins associated with transport AA and glucose, protein turnover, metabolism, and antioxidant pathways in skeletal muscle. Sixty multiparous Holstein cows were used in a block design and assigned to a control or RPM diet from -28 to 60 d in milk. The RPM was fed at a rate of 0.09% or 0.10% of dry matter intake (DMI) during the prepartal and postpartal periods to achieve a target Lys:Met ratio in the metabolizable protein of ∼2.8:1. Muscle biopsies from the hind leg of 10 clinically healthy cows per diet collected at -21, 1, and 21 d relative to calving were used for western blotting of 38 target proteins. Statistical analysis was performed using the PROC MIXED statement of SAS version 9.4 (SAS Institute Inc.) with cow as random effect, whereas diet, time, and diet × time were the fixed effects. Diet × time tended to affect prepartum DMI, with RPM cows consuming 15.2 kg/d and controls 14.6 kg/d. However, diet had no effect on postpartum DMI (17.2 and 17.1 ± 0.4 kg/d for control and RPM, respectively). Milk yield during the first 30 d in milk was also not affected by diet (38.1 and 37.5 ± 1.9 kg/d for control and RPM, respectively). Diet or time did not affect the abundance of several AA transporters or the insulin-induced glucose transporter (SLC2A4). Among evaluated proteins, feeding RPM led to lower overall abundance of proteins associated with protein synthesis (phosphorylated EEF2, phosphorylated RPS6KB1), mTOR activation (RRAGA), proteasome degradation (UBA1), cellular stress responses (HSP70, phosphorylated MAPK3, phosphorylated EIF2A, ERK1/2), antioxidant response (GPX3), and de novo synthesis of phospholipids (PEMT). Regardless of diet, there was an increase in the abundance of the active form of the master regulator of protein synthesis phosphorylated MTOR and the growth-factor-induced serine/threonine kinase phosphorylated AKT1 and PIK3C3, whereas the abundance of a negative regulator of translation (phosphorylated EEF2K) decreased over time. Compared with d 1 after calving and regardless of diet, the abundance of proteins associated with endoplasmic reticulum stress (XBP1 spliced), cell growth and survival (phosphorylated MAPK3), inflammation (transcription factor p65), antioxidant responses (KEAP1), and circadian regulation (CLOCK, PER2) of oxidative metabolism was upregulated at d 21 relative to parturition. These responses coupled with the upregulation of transporters for Lys, Arg, and His (SLC7A1) and glutamate/aspartate (SLC1A3) over time were suggestive of dynamic adaptations in cellular functions. Overall, management approaches that could take advantage of this physiological plasticity may help cows make a smoother transition into lactation.

Farnesoid X receptor protects against lipopolysaccharide-induced endometritis by inhibiting ferroptosis and inflammatory response

Endometritis is an inflammatory condition that affects the endometrium; it is induced by bacterial infection and often leads to infertility and repeated abortions. Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily that mediates a variety of inflammatory diseases. In the present study, we determined the protective effects of FXR on lipopolysaccharide (LPS)-induced endometritis in mice and the underlying mechanisms. The results showed that LPS administration reduced the expression of FXR in the uterus, and treatment with the FXR agonist GW4064 and fexaramine significantly alleviated the endometritis induced by LPS. In addition, compared with wild-type (WT) mice, FXR-knockout mice had more severe inflammatory responses in their uteri after LPS treatment. Moreover, ferroptosis was increased during LPS-induced endometritis, as shown by increased levels of malondialdehyde (MDA) and iron, and decreased levels of superoxide dismutase (SOD), glutathione (GSH), GXP4 and SLC7A11. In addition, inhibition of ferroptosis by treatment with ferrostation-1 (Fer-1) and liproxstatin (Lip-1) alleviated LPS-induced endometritis. Additionally, FXR-knockout mice were used to determine the relationship between FXR and ferroptosis. The results showed that knockout of FXR induced ferroptosis, and an FXR agonist inhibited LPS-induced ferroptosis. Finally, the regulatory effects of obeticholic acid (OCA) on FXR/ferroptosis and endometritis were assessed. The results showed that treatment with OCA increased the expression of FXR, decreased the levels of ferroptosis, and inhibited the endometritis induced by LPS. In conclusion, the results showed that activation of FXR can alleviate LPS-induced endometritis by inhibiting ferroptosis, and FXR may be a potential therapeutic target for treating endometritis.

Natural Flavonoids and Ferroptosis: Potential Therapeutic Opportunities for Human Diseases

Flavonoids are a class of bioactive phytochemicals containing a core 2-phenylchromone skeleton and are widely found in fruits, vegetables, and herbs. Such natural compounds have gained significant attention due to their various health benefits. Ferroptosis is a recently discovered unique iron-dependent mode of cell death. Unlike traditional regulated cell death (RCD), ferroptosis is associated with excessive lipid peroxidation on cellular membranes. Accumulating evidence suggests that this form of RCD is involved in a variety of physiological and pathological processes. Notably, multiple flavonoids have been shown to be effective in preventing and treating diverse human diseases by regulating ferroptosis. In this review, we introduce the key molecular mechanisms of ferroptosis, including iron metabolism, lipid metabolism, and several major antioxidant systems. Additionally, we summarize the promising flavonoids targeting ferroptosis, which provides novel ideas for the management of diseases such as cancer, acute liver injury, neurodegenerative diseases, and ischemia/reperfusion (I/R) injury.

Dissecting the potential role of ferroptosis in liver diseases: an updated review

Ferroptosis is a novel form of cell death, manifested by iron-dependent, non-apoptotic manner resulting from the intracellular accumulation of large clusters of reactive oxygen species (ROS) and lipid peroxides due to abnormal iron metabolism. Since the liver is the main organ of human body for storing iron, it is essential to perform in-depth investigation on the role and mechanistic basis of ferroptosis in the context of divergent liver diseases. We previously summarized the emerging role of ferroptosis among various liver diseases, however, the past few years have been a surge in research establishing ferroptosis as the molecular basis or treatment option. This review article concentrated on the accumulating research progress of ferroptosis in a range of liver diseases such as acute liver injury/failure (ALI/ALF), immune-mediated hepatitis, alcoholic liver disease (ALD), nonalcoholic fatty liver disease and liver fibrosis. Ferroptosis may be a promising target for the prevention and treatment of various liver diseases, providing a strategy for exploring new therapeutic avenues for these entities.

High fructose-induced skeletal muscle insulin resistance could be alleviated by berberine via AMPD1 and ADSL

AMP-activated protein kinase (AMPK) is a master regulator of energy homeostasis that is activated in response to an elevated intracellular AMP/ATP ratio. Although many studies have shown berberine is an AMPK activator widely used in metabolic syndrome, how to properly control AMPK activity remains obscure. Our present study aimed to examine the protective effect of berberine against fructose-induced insulin resistance in rats and L6 cells, as well as its potential activation mechanism on AMPK. The results showed that berberine effectively reversed body weight gain, Lee's index, dyslipidemia and insulin intolerance. Moreover, berberine alleviated inflammatory response, antioxidant capacity and promoted glucose uptake in vivo and in vitro. The beneficial effect was associated with upregulation of both Nrf2 and AKT/GLUT4 pathways, which were regulated by AMPK. Notably, berberine could increase the level of AMP and the ratio of AMP/ATP, then further activate AMPK. Mechanistic experiments revealed that berberine suppressed the expression of adenosine monophosphate deaminase 1 (AMPD1) and promoted the expression of adenylosuccinate synthetase (ADSL). Taken together, berberine exerted excellent therapeutic effect on insulin resistance. And its mode of action may be related to the AMP-AMPK pathway by regulating AMPD1 and ADSL.

Deferasirox alleviates DSS-induced ulcerative colitis in mice by inhibiting ferroptosis and improving intestinal microbiota

AIMS

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) caused by multiple factors. Studies have shown that epithelial cell damage was associated with ferroptosis in UC. Therefore, our research focused on the effects and mechanism of iron chelator deferasirox in UC.

MAIN METHODS

The UC model was induced by 2.5 % dextran sulfate sodium salt (DSS) and administered with deferasirox (10 mg/kg) for 7 days. Histological pathologies, inflammatory response, ferrous iron contents, oxidative stress and ferroptosis regulators were determined. Intestinal microbiota alteration and short-chain fatty acids (SCFAs) production were analyzed through 16S rRNA gene sequencing and targeted metabolomics.

KEY FINDINGS

Deferasirox significantly relieved the DSS-induced UC in mice, as evidenced by weight loss, survival rate, colon length shortening disease activity index (DAI) score and histology score. Deferasirox treatment reduced the level of pro inflammatory cytokines (IL-1β, IL-6, TNF-α and INF-γ). Ferroptosis was induced in mice with UC, as evidenced by ferrous iron accumulation, increased ROS production, SOD and GSH depletion, decreased the expression of GPX-4 and FTH, accompanied by increased expression of TF. Deferasirox treatment strongly reversed the alterations caused by ferroptotic characteristics in DSS-induced mice. Moreover, deferasirox treatment reshaped the composition of intestinal microbiota. The results revealed the genera of norank_f__Muribaculaceae, Lachnospiraceae_NK4A136_group, Prevotellaceae_UCG-001, Odoribacter and Blautia were increased distinctly, while Escherichia-Shigella and Streptococcus were significantly decreased by deferasirox treatment. Targeted metabolomics analysis indicated the SCFAs production enhanced in deferasirox-treated mice.

SIGNIFICANCE

Our results suggested that deferasirox could treat DSS-induced UC in mice by inhibiting ferroptosis and improving intestinal microbiota.