Arbutin alleviates fatty liver by inhibiting ferroptosis via FTO/SLC7A11 pathway

Hyperlipidemia Triggers Trophoblast Cell Dysfunction and Preeclampsia via the AMPK/GATA3/FTL Pathway

BACKGROUND

Preeclampsia, a severe pregnancy complication with an incompletely deciphered cause, is strongly associated with hyperlipidemia. Our previous studies demonstrated that FTL (ferritin light chain) expression was diminished in preeclampsia placentas and that FTL downregulation inhibited trophoblast invasiveness and migration while promoting apoptosis, contributing to preeclampsia development. However, the potential interplay between hyperlipidemia and FTL in the pathogenesis of preeclampsia, as well as the regulatory mechanism involved, remains to be elucidated.

METHODS

We conducted Spearman correlation analysis, used a high-fat diet-fed mice model, cell culture, and molecular biology assays, including immunohistochemistry, chromatin immunoprecipitation, and dual-luciferase reporter gene assays, to explore the impact of hyperlipidemia on the development of preeclampsia and to elucidate the molecular mechanisms involved.

RESULTS

Pregnant women with preeclampsia presented elevated serum total cholesterol, triglycerides, and low-density lipoprotein, with reduced high-density lipoprotein. Similarly, high-fat diet-fed mice exhibited dyslipidemia and preeclampsia-like characteristics. FTL expression was reduced in the placentas of patients with preeclampsia and high-fat diet-fed pregnant mice. In vitro, palmitic acid treatment reduced FTL expression, increased oxidative stress, and impaired trophoblast migration and invasion. GATA3 (GATA binding protein 3) was predicted to be an upstream transcription factor for FTL, with its knockdown reducing and its overexpression increasing FTL levels. Further analysis indicated that palmitic acid suppressed FTL expression by inhibiting GATA3 nuclear translocation and that AMPK (AMP-activated protein kinase) activation rescued FTL expression and restored trophoblast function.

CONCLUSIONS

This study revealed that high lipid levels contribute to preeclampsia by downregulating FTL through the AMPK-GATA3 pathway, highlighting potential therapeutic targets for preeclampsia management.

Vine tea (Ampelopsis grossedentata) ameliorates chronic alcohol-induced hepatic steatosis, oxidative stress, and inflammation via YTHDF2/PGC-1α/SIRT3 axis

For over a millennium, the leaves of Ampelopsis grossedentata (Hand.-Mazz.) W. T. Wang, commonly known as vine tea, have been revered as a popular tea and traditional herbal remedy, possessing antioxidant, anti-inflammatory, hepatoprotective, and antiviral properties. In recent years, the incidence of alcohol-related liver injury has been on the rise, imposing a significant public health burden worldwide. Previous studies have indicated that extracts of vine tea (AGE) can ameliorate alcoholic liver disease (ALD), yet the pharmacological mechanisms underlying this effect remain poorly understood. In this study, we first employed UPLC-Q-TOF-MS to analyze the chemical constituents of AGE. Subsequently, an ALD model was established in mice fed with Lieber-DeCarli diet, and the hepatoprotective benefits of AGE were assessed by measuring biochemical indicators and hepatic pathological changes. Moreover, a suite of bioinformatics tools, including transcriptomics, weighted gene co-expression network analysis, and single-cell data mining, were utilized to reveal that the YTHDF2/PGC-1α/SIRT3 signaling axis may be the potential mechanism by which AGE exerts its anti-ALD effects. Additionally, Western blotting and immunofluorescence staining techniques were employed to further substantiate the aforementioned mechanism. Our findings demonstrate that administration of vine tea significantly alleviated chronic ethanol-induced hepatic lipid accumulation, oxidative stress, and inflammation. Notably, knockdown of YTHDF2 partially protected the liver from ethanol-induced injury. Mechanistically, bioinformatics analysis and in vitro and in vivo experiments identified YTHDF2 as a key pharmacological target of AGE in treating ALD, acting through the downstream PGC-1α/SIRT3 pathway. In summary, in this study, we provide the first evidence that AGE mitigates ethanol-induced liver injury by inhibiting YTHDF2 and enhancing the expression of PGC-1α and SIRT3. Vine tea, as a tea food with unique medicinal value, shows significant potential and value in the treatment of ALD.

Mesenchymal stem cell-derived extracellular vesicles attenuate ferroptosis in aged hepatic ischemia/reperfusion injury by transferring miR-1275

With an aging global population, the proportion of aged donor livers in graft pools is steadily increasing. Compared to young livers, aged livers exhibit heightened susceptibility to hepatic ischemia/reperfusion injury (HIRI), which significantly limits their utilisation in liver transplantation (LT) and exacerbates organ shortages. Our previous study demonstrated that ferroptosis is a pivotal trigger for HIRI vulnerability in aged livers. However, effective clinical strategies for the inhibition of ferroptosis remain elusive. Utilizing an aged mouse HIRI model, primary hepatocytes, and human liver organoids, this study provides hitherto undocumented evidence that mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) effectively alleviate HIRI in aged livers by inhibiting ferroptosis. Mechanistically, miR-1275, which was significantly enriched within MSC-EVs, was transferred to hepatocytes. Subsequently, miR-1275 downregulated the expression of SLC39A14, a crucial iron transporter that is upregulated in aged livers and plays a pivotal role in promoting ferroptosis. Furthermore, we found a negative correlation between SLC39A14 levels and prognosis of aged donor liver recipients using clinical LT samples. Silencing miR-1275 in MSC-EVs or modulating SLC39A14 levels in aged livers reversed MSC-EV-mediated mitigation of ferroptosis. Collectively, these findings revealed the novel therapeutic potential of MSC-EVs in attenuating aged HIRI, suggesting a promising treatment for improving prognosis and preventing serious complications in recipients of aged liver grafts during LT.

Hinokitiol ameliorates MASH in mice by therapeutic targeting of hepatic Nrf2 and inhibiting hepatocyte ferroptosis

BACKGROUND

Metabolic dysfunction-associated steatohepatitis (MASH), an advanced stage of metabolic dysfunction-associated steatotic liver disease (MASLD), still lacks approved effective clinical drugs. Ferroptosis, a form of regulated cell death driven by excessive iron accumulation and uncontrollable lipid peroxidation, has been proven to be a trigger of inflammation and initiation of steatohepatitis. The pathogenic interplay is modulated by oxidative stress, while the Nrf2-mediated antioxidant response plays a regulatory role in ferroptosis. Phytochemical hinokitiol (Hino) has demonstrated positive efficacy in hepatocellular carcinoma (HCC) in the reported work, but it remains unknown whether its therapeutic effect attributes to delaying the progress of steatohepatitis to HCC.

PURPOSE

This work aimed to systemically investigate the significance of ferroptosis in the pathogenesis of MASH and to demonstrate that Hino, a bioactive monoterpene compound, attenuates the primary pathological characteristics of MASH via promotion of Nrf2/GPX4 signaling.

METHODS

In this work, a MASH model was established using the high-fat/high-cholesterol (HFHC) diet-fed in vivo and palmitic acid/oleic acid (PO)-stimulated hepatocytes in vitro. Biochemical indexes, pathological analysis, western blot, PCR assay, energy metabolic phenotype, molecular docking, and confirmatory assays were performed comprehensively to reveal the key link between the Nrf2/GPX4 axis and the treatment of MASH.

RESULTS

Under MASH conditions with increased oxidative stress, we show that Nrf2 was remarkable downregulated in HFHC diet-fed mice and PO-managed hepatocytes. Mechanistically, hepatic upregulation of Nrf2 through phytochemical Hino supplementation inhibited ferroptosis, enhanced lipid metabolism, and thereby alleviated hepatic steatosis, inflammation, and fibrosis. Conversely, silencing Nrf2 in hepatocytes further promoted the accumulation of key markers of ferroptosis and aggravated MASH phenotypes.

CONCLUSION

Increased ferroptosis promoted steatosis which further drove inflammation and hepatic fibrosis. Our results suggested the significance of Nrf2 in ameliorating MASH, which was regulated through Hino. Thus, targeted inhibition of ferroptosis through Hino administration is a feasible and effective approach for treating MASH.

The Role of Solute Carrier Family Transporters in Hepatic Steatosis and Hepatic Fibrosis

Solute carrier (SLC) family transporters are crucial transmembrane proteins responsible for transporting various molecules, including amino acids, electrolytes, fatty acids, and nucleotides. To date, more than fifty SLC transporter subfamilies have been identified, many of which are linked to the progression of hepatic steatosis and fibrosis. These conditions are often caused by factors such as non-alcoholic fatty liver disease and non-alcoholic steatohepatitis, which are major contributors to the global liver disease burden. The activity of SLC members regulates the transport of substrates across biological membranes, playing key roles in lipid synthesis and metabolism, mitochondrial function, and ferroptosis. These processes, in turn, influence the function of hepatocytes, hepatic stellate cells, and macrophages, thereby contributing to the development of hepatic steatosis and fibrosis. Additionally, some SLC transporters are involved in drug transport, acting as critical regulators of drug-induced hepatic steatosis. Beyond substrate transport, certain SLC members also exhibit additional functions. Given the pivotal role of the SLC family in hepatic steatosis and fibrosis, this review aimed to summarize the molecular mechanisms through which SLC transporters influence these conditions.

Ferroptosis in Endometriosis: Traditional Chinese Medicine Interventions and Mechanistic Insights

Endometriosis (EMS) is a chronic, estrogen-dependent inflammatory disease affecting 5-10% of women of reproductive age, characterized by the growth of endometrial tissue on the outside of the uterus. The dysregulation of iron metabolism leads to the accumulation of iron ions at the lesion sites, resulting in oxidative stress and pro-inflammatory responses that promote the progression of EMS. The mechanisms underlying ferroptosis in EMS primarily involve iron accumulation, lipid peroxidation, and loss of glutathione peroxidase 4 activity. These mechanisms confer resistance to ferroptosis within the ectopic tissues and facilitate cell survival and proliferation. Traditional Chinese medicine (TCM) has demonstrated therapeutic potential for modulating ferroptosis. Studies have shown that TCM monomers may regulate ferroptosis by modulating iron transport proteins and anti-oxidant defense mechanisms. TCM formulas employ distinct treatment strategies depending on the stage of EMS: in the early stages, they promote ferroptosis to control lesion growth, whereas in the later stages, they inhibit ferroptosis to reduce oxidative stress and inflammation in order to improve reproductive health and slow disease progression. This study provides a new perspective on potential therapeutic strategies for the management of EMS by summarizing the role of ferroptosis in its pathological mechanisms and reviewing findings on the use of TCM in regulating ferroptosis.

The emerging role of E3 ubiquitin ligases and deubiquitinases in metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide, with a prevalence as high as 32.4%. MASLD encompasses a spectrum of liver pathologies, ranging from steatosis to metabolic dysfunction-associated steatohepatitis (MASH), fibrosis, and, in some cases, progression to end-stage liver disease (cirrhosis and hepatocellular carcinoma). A comprehensive understanding of the pathogenesis of this highly prevalent liver disease may facilitate the identification of novel targets for the development of improved therapies. E3 ubiquitin ligases and deubiquitinases (DUBs) are key regulatory components of the ubiquitin‒proteasome system (UPS), which plays a pivotal role in maintaining intracellular protein homeostasis. Emerging evidence implicates that aberrant expression of E3 ligases and DUBs is involved in the progression of MASLD. Here, we review abnormalities in E3 ligases and DUBs by (1) discussing their targets, mechanisms, and functions in MASLD; (2) summarizing pharmacological interventions targeting these enzymes in preclinical and clinical studies; and (3) addressing challenges and future therapeutic strategies. This review synthesizes current evidence to highlight the development of novel therapeutic strategies based on the UPS for MASLD and progressive liver disease.

Cutting edge: ferroptosis in metabolic dysfunction-associated steatotic liver disease (MASLD) pathogenesis and therapy

Ferroptosis denotes a distinct form of controlled cell death marked by substantial iron buildup and significant lipid peroxidation, playing a crucial role in several disease processes linked to cell death. Given the liver's essential functions in iron and lipid metabolism and its vulnerability to oxidative damage, more research has investigated the correlation between ferroptosis and numerous hepatic diseases, including metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD). NAFLD has arisen as a worldwide public health concern due to elevated morbidity and high death rates. The pathogenesis of MASLD remains incompletely elucidated. Recent data suggests that ferroptosis is crucial in the pathophysiology of MASLD; nevertheless, the specific processes by which ferroptosis influences MASLD remain unclear. The present review summarizes the molecular processes of ferroptosis and its intricate regulatory networks, outlines the differing impacts of ferroptosis at different stages of MASLD, and examines possible approaches targeting ferroptosis for the therapy of MASLD, suggesting a novel approach for its management.

Caffeine ameliorates metabolic-associated steatohepatitis by rescuing hepatic Dusp9

Caffeine (CAFF) is abundant in black coffee. As one of the most widely consumed beverages globally, coffee has been the focus of increasing clinical and basic research, particularly regarding its benefits in alleviating metabolic dysfunction-associated steatotic liver disease (MASLD). However, the therapeutic effects of CAFF on metabolic-associated steatohepatitis (MASH) and the underlying mechanisms remain unclear. In this study, we demonstrated that CAFF potently reduced hepatic steatosis, inflammation, and early-stage liver fibrosis in MASH mice induced by prolonged (36 weeks) high-fat high-carbohydrate (HFHC) diets and high-fat diets combined with carbon tetrachloride (CCl4) injections. By using multiple target-identifying strategies, including surface plasmon resonance (SPR), cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS) assay, we identified dual-specificity phosphatase 9 (Dusp9) as a key therapeutic target, which was diminished by HFHC but restored with CAFF treatment. Dusp9 knockdown in vivo and in vitro exacerbated glycolipid metabolism disorders and stunningly counteracted the systemic therapeutic effects of CAFF in the MASH models. In addition, CAFF inactivated the ASK1-p38/JNK, a downstream signaling pathway of Dusp9, which regulates inflammation and apoptosis. Our study highlights the multifaceted benefits of CAFF in treating MASH by rescuing hepatic Dusp9 expression, thereby reversing glycolipid metabolism disorders, liver inflammation, and fibrosis. These findings provide experimental evidence supporting the clinical and daily use of CAFF and black coffee in managing MASH patients.

Downregulation of SLC7A11 by Bis(4-Hydroxy-3,5-Dimethylphenyl) Sulfone Induces Ferroptosis in Hepatocellular Carcinoma Cell

The progression of tumors has been demonstrated to have a strong correlation with ferroptosis. Bis(4-hydroxy-3,5-dimethylphenyl) sulfone (TMBPS) has been shown to effectively inhibit the proliferation of hepatocellular carcinoma (HCC), but its underlying mechanism is not clear. In this study, ferrostatin-1 (Fer-1) was employed to explore whether the death of HCC cells caused by TMBPS is related to ferroptosis. The intracellular lipid peroxides, Fe2+, malondialdehyde (MDA), GSH/GSSG, mitochondrial morphology, and potential of HCC cells were detected after TMBPS treatment. The target of TMBPS was predicted by the molecular docking approach and verified via quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and cellular heat transfer assay (CETSA). Our results revealed that Fer-1 effectively reversed the cell death induced by TMBPS in HCC cells. Treatment with TMBPS induced typical ferroptosis features, including increased levels of intracellular lipid peroxides, Fe2+, and MDA, along with a decreased GSSH/GSH ratio and mitochondrial potential. These effects were reversed by overexpressing SLC7A11. These findings suggest that the cell death triggered by TMBPS in HCC cells is linked to ferroptosis, potentially mediated through the inhibition of SLC7A11 expression.

Research progress of cysteine transporter SLC7A11 in endocrine and metabolic diseases

SLC7A11, often called xCT, belongs to the SLC family of transporters, which mediates the cellular influx of cystine and the efflux of glutamate. These transport processes are crucial for synthesizing GSH, enhancing the cell's ability to mitigate oxidative stress (OS). Emerging studies highlight the pivotal role of OS in triggering and exacerbating various metabolic and endocrine disorders, underlining the critical importance of regulating SLC7A11 expression levels. This study reviews the diverse roles of SLC7A11 in endocrine and metabolic diseases, examining its relationship with the metabolism of three key nutrients: proteins and amino acids, carbohydrates, and lipids. Additionally, the involvement of SLC7A11 in the onset and development of various common endocrine and metabolic disorders is analyzed. Additionally, it provides an overview of the current clinical and experimental use of SLC7A11 inhibitors and agonists. This review aims to offer insightful perspectives into the involvement of SLC7A11 in endocrine and metabolic pathologies and to foster the development of innovative therapeutic strategies that target SLC7A11.

Puerarin Ameliorates the Ferroptosis in Diabetic Liver Injure Through the JAK2/STAT3 Pathway Inhibition Based on Network Pharmacology and Experimental Validation

Background

Diabetic liver injury (DLI) is a common complication of diabetes mellitus (DM), which seriously endangers the health of diabetic patients. Puerarin, the main active component of Pueraria lobata, has shown positive effects in lowering blood glucose and lipids, resisting oxidative stress, and protecting the liver. However, the mechanism of protective effect of Puerarin on DLI remains unclear.

Methods

Various databases were used to screen for targets of Puerarin, ferroptosis and DLI. Protein-protein interaction (PPI) network and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were used to predict key targets and pathways. Molecular docking was used to predict the interactions between Puerarin and core targets. KK/Upj-Ay/J (KKAy) mice and high glucose (HG)-induced AML12 cells were used to study the protective effect of Puerarin on DLI. The molecular mechanisms by which Puerarin acts were further verified by in vivo and in vitro experiments.

Results

KEGG analysis indicated that the JAK/STAT pathway might be related to the anti-DLI effect of Puerarin. Molecular docking revealed that Puerarin has good affinity for JAK2 and STAT3. In vivo, Puerarin (80 mg/kg) reduced body weight, blood glucose, blood lipids and liver function in KKAy mice fed a high-sugar, high-fat diet. Puerarin also ameliorated hepatic pathological changes and inflammatory responses, and attenuated oxidative stress and iron overload in KKAy mice. Western blotting results showed that Puerarin could regulate the expression of proteins related to JAK2/STAT3 pathway and ferroptosis pathway. In vitro, Puerarin (25, 50, 100 μM) increased cell viability and decreased steatosis and liver function indexes in AML12 cells induced by HG (30 mm) to varying degrees. More importantly, AG490 blocker experiments showed that the regulation of ferroptosis process by Puerarin was dependent on the JAK2/STAT3 pathway.

Conclusion

In conclusion, this study revealed Puerarin may regulate the ferroptosis process by inhibiting the JAK2/STAT3 pathway for the treatment of DLI.

Curcumin-induced exosomal FTO from bone marrow stem cells alleviates sepsis-associated acute kidney injury by modulating the m6A methylation of OXSR1

Curcumin and bone marrow stem cells (BMSCs)-derived exosomes are considered to be useful for the treatment of many human diseases, including sepsis-associated acute kidney injury (SA-AKI). However, the role and underlying molecular mechanism of curcumin-loaded BMSCs-derived exosomes in the progression of SA-AKI remain unclear. Exosomes (BMSCs-EXOCurcumin or BMSCs-EXOControl) were isolated from curcumin or DMSO-treated BMSCs, and then co-cultured with LPS-induced HK2 cells. Cell proliferation and apoptosis were determined by cell counting kit 8 (CCK8) assay, 5-ethynyl-2-deoxyuridine (EdU) assay, and flow cytometry. Enzyme-linked immunosorbent assay (ELISA) was used for examining inflammatory factors. The levels of SOD, MDA, and ROS were tested to assess oxidative stress. The levels of fat mass and obesity-associated protein (FTO) and oxidative stress responsive 1 (OXSR1) were detected by quantitative real-time PCR and western blot. Methylated RNA immunoprecipitation (MeRIP) assay and RNA immunoprecipitation (RIP) assay were used for measuring the interaction between FTO and OXSR1. BMSCs-EXOCurcumin treatment could inhibit LPS-induced HK2 cell apoptosis, inflammation, and oxidative stress. FTO was downregulated in SA-AKI patients and LPS-induced HK2 cells, while was upregulated in BMSCs-EXOCurcumin. Exosomal FTO from curcumin-induced BMSCs suppressed apoptosis, inflammation, and oxidative stress in LPS-induced HK2 cells. FTO decreased OXSR1 expression through m6A modification, and the inhibitory effect of FTO on LPS-induced HK2 cell injury could be eliminated by OXSR1 overexpression. In animal experiments, BMSCs-EXOCurcumin alleviated kidney injury in SA-AKI mice models by regulating FTO/OXSR1 axis. In conclusion, exosomal FTO from curcumin-induced BMSCs reduced OXSR1 expression to alleviate LPS-induced HK2 cell injury and improve kidney function in CLP-induced mice models, providing a new target for SA-AKI.

Cordycepin alleviates metabolic dysfunction-associated liver disease by restoring mitochondrial homeostasis and reducing oxidative stress via Parkin-mediated mitophagy

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) keeps rising with only a few drugs available. The present study aims to investigate the effects and mechanisms of cordycepin on MASLD. Male C57BL/6 mice were induced with a 90-day high-fat diet (HFD) and intraperitoneal administration with streptozotocin to establish MASLD murine model. Then they were randomly divided into the HFD and cordycepin groups (15, 30, 45 mg/kg). Cordycepin was orally given for 30 days. Serum total cholesterol (TC), triacylglyceride (TG), and aspartate aminotransferase (AST) levels were measured. L02 cells were induced by oleate acid (OA) or lipopolysaccharides (LPS), and treated with cordycepin or combined with inhibitors including chloroquine, 3-Methyladenine, and compound C. Atg7 and Parkin were knocked down in L02 cells using siRNA. Oil Red O and Nile Red staining for measuring lipid deposition. Mitochondria were visualized by transfection with mCherry-TOMM20-N10. Quantitative real-time PCR, Western blotting, and immunofluorescence staining were used to determine expressions of key molecules in inflammation, lipid metabolism, mitochondria homeostasis, and oxidative stress. Cordycepin significantly mitigated lipid deposition and ballooning in the livers of MASLD mice. Serum TC, TG, and AST levels were decreased by cordycepin. Cordycepin alleviated OA-induced lipid deposition and LPS-induced inflammation in L02 cells, attenuated oxidative stress, promoted autophagy, and maintained the autophagic flux by activating AMP-activated protein kinase (AMPK). Cordycepin reduced the accumulation of impaired mitochondria by enhancing Parkin-dependent mitophagy and promoting mitochondrial biogenesis. Cordycepin alleviates MASLD by restoring mitochondrial homeostasis and reducing oxidative stress via activating the Parkin-mediated mitophagy.

Chitosan oligosaccharide alleviates DON-induced liver injury via suppressing ferroptosis in mice

Chitosan oligosaccharide (COS), a water-soluble derivative of chitin, has been recognized for its diverse biological properties. Deoxynivalenol (DON) is a prevalent mycotoxin, causing extreme liver damage. However, the mechanism whereby COS alleviates DON-induced liver injury remains unclear. In the present study, C57BL/6 mice were randomly divided into four groups: control (CON), DON (1.0 mg/d/kg BW DON), COS (200 mg/d/kg BW COS), and COS+DON (200 mg/d/kg BW COS + 1.0 mg/d/kg BW DON), with a period of 28 days. The results indicated that COS effectively reversed DON-induced weight loss, elevated liver index, and liver hemorrhage and swelling in mice. Moreover, COS significantly reduced liver reactive oxygen species (ROS) levels, malondialdehyde (MDA) content, and lactate dehydrogenase (LDH) release in DON-exposed mice, while restoring the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC). Further investigations revealed that COS modulated the expressions of pro-inflammatory cytokines and anti-apoptotic proteins through stimulation of the Nrf2/HO-1 signaling pathway and suppression of the NF-κB signaling pathway. Additionally, COS inhibited ferroptosis by modulating the SLC7A11/GSH/GPX4 pathway and the expression of FTH1 and FLC proteins, thereby reducing lipid peroxidation accumulation and iron overload. In summary, this research showed that COS mitigated DON-induced liver injury in mice by alleviating DON-induced oxidative stress, inflammation, apoptosis, and ferroptosis via modulating the Nrf2/HO-1/NF-κB and GPX4 signaling pathways. These results offer a theoretical basis for the development and application of COS as a novel liver protectant and propose innovative therapeutic strategies for combating DON-induced liver damage.

Testosterone deficiency aggravates diet-induced non-alcoholic fatty liver disease by inducing hepatocyte ferroptosis via targeting BMAL1 in mice

BACKGROUND

Testosterone deficiency is linked to an increased prevalence of non-alcoholic fatty liver disease (NAFLD), although the mechanisms underlying this association are not fully understood. Ferroptosis, a regulated cell death pathway driven by iron-dependent lipid peroxidation, has been suggested to play a role in NAFLD pathogenesis. Since testosterone deficiency is associated with lipid disorders and iron deposition, we hepothesize that ferroptosis may be involved in the pathogenesis of diet-induced NAFLD exacerbated by testosterone deficiency.

METHODS

Apolipoprotein E (APOE-/-) mice were subjected to sham surgery or bilateral castration and subsequently fed a high-fat diet for 16 weeks. Liver gene expression was analyzed using RNA sequencing. Additional assessments included blood analysis, histological staining, measurement of iron and antioxidant enzyme levels, quantitative real-time PCR, Western blotting, and electron microscopy. The effects of testosterone on ferroptosis induced by free fatty acids (FFAs) and Erastin were further investigated in HepG2 cells in vitro.

RESULTS

Testosterone deficiency resulted in increased hepatic lipid accumulation and macrovesicular steatosis in high-fat diet-fed APOE-/- mice, accompanied by hepatic inflammation, fibrosis, and elevated liver enzyme levels. Transcriptomic analysis revealed that testosterone deficiency affects ferroptosis and circadian rhythm-related signaling pathways. Castrated APOE-/- mice exhibited significantly higher hepatic iron deposition, lipid peroxidation, and expression of key ferroptosis-related proteins, along with decreased Brain and muscle ARNT-like gene 1 (BMAL1) protein expression. In vitro, testosterone treatment reduced lipid and iron accumulation and lipid peroxidation in HepG2 cells subjected to FFAs and Erastin. Moreover, BMAL1 knockdown negated the protective effects of testosterone against ferroptosis in hepatocytes.

CONCLUSION

Our study demonstrated that testosterone deficiency exacerbates NAFLD induced by a high-fat diet by promoting hepatocyte ferroptosis through modulation of the circadian protein BMAL1.

PROTAC-mediated FTO protein degradation effectively alleviates diet-induced obesity and hepatic steatosis

Demethylation of N6-Methyladenosine (m6A) by fat mass and obesity-associated protein (FTO) occurs in the development of obesity and fatty liver disease. In this study, we synthesized FTO-degradation targeted chimera (FTO-DT), which exhibited excellent lipid-lowering activity at low concentration. At a concentration of 0.33 nM, the FTO-DT continuously and efficiently degraded FTO protein and reduced fat deposition. The FTO-DT improved energy metabolism and oxidative stress by increasing intracellular m6A levels, and further reduced fat deposition in hepatocytes, adipocytes, and mice fed a high-fat diet. The findings support the potential of FTO degradation by FTO-DT as a therapy for obesity and metabolic-associated fatty liver disease (MAFLD). This study provides a theoretical basis for the application of PROTACs in the treatment of metabolic disease and describes a novel approach for the development of drugs targeting metabolic disorders.

Sodium valproate ablates ferroptosis in kainic acid-induced epileptic seizure via suppressing lysyl oxidase

The objective of this study is to explore whether sodium valproate (VPA) alleviates epileptic seizures via suppressing lysyl oxidase (Lox)-mediated ferroptosis. Epileptic seizure mouse model was prepared via intrahippocampal injection of kainic acid (250 ng/μl). After treatment with kainic acid, VPA was injected intraperitoneally by the dose of 250 mg/kg twice daily for 4 days. Ferroptosis-associated indices including lipid peroxides (LPO) level and Ptgs2 mRNA in hippocampal tissue samples were detected. Additionally, effects of VPA on Lox mRNA and enzymatic activity were assessed by quantitative real-time PCR and a commercial kit, respectively. Neuronal survival was assessed by Nissl staining. In kainic acid-induced epileptic seizure mouse model, VPA significantly suppressed LPO level and Ptgs2 mRNA and the suppression of ferroptosis was positively correlated with its anti-seizure effect. Lox mRNA and enzymatic activity were also found to decrease in hippocampus of epileptic seizure mice after VPA treatment. Furthermore, overexpression of Lox via adeno-associated virus infection remarkably abrogated the inhibitory effect of VPA on ferroptosis and neuronal impairment together with its anti-seizure effect. VPA suppresses Lox-mediated ferroptosis process, which can provide the explanation for its anti-seizure property.

Alterations in Glutathione Redox Homeostasis in Metabolic Dysfunction-Associated Fatty Liver Disease: A Systematic Review

Low molecular weight (LMW) thiols, particularly glutathione, play pathogenic roles in various multiorgan diseases. The liver is central for the production and systemic distribution of LMW thiols; thus, it is particularly susceptible to the imbalance of redox status that may determine increased oxidative stress and trigger the liver damage observed in metabolic dysfunction-associated steatotic liver disease (MASLD) models and humans. Indeed, increased LMW thiols at the cellular and extracellular levels may be associated with the severity of MASLD. Here, we present a systematic literature review of recent studies assessing the levels of LMW thiols in MASLD in in vivo and in vitro models and human subjects. Based on the PRISMA 2020 criteria, a search was conducted using PubMed and Scopus by applying inclusion/exclusion filters. The initial search returned 1012 documents, from which 165 eligible studies were selected, further described, and qualitatively analysed. Of these studies, most focused on animal and cellular models, while a minority used human fluids. The analysis of these studies revealed heterogeneity in the methods of sample processing and measurement of LMW thiol levels, which hinder cut-off values for diagnostic use. Standardisation of the analysis and measure of LMW thiol is necessary to facilitate future studies.

Liposome preparation of alpha-arbutin: stability and toxicity assessment using mouse B16F10 melanoma cells

Melanoma is the most aggressive type of skin cancer, with few therapeutic alternatives following metastasis development. In recent years, drug delivery-associated nanotechnology has shown promising targeted results with diminished adverse effects compared to conventional treatments. This study aimed to (1) examine the effects of plant-derived α-arbutin, a natural compound and (2) compare these findings with bioactively developed liposomes containing α-arbutin utilizing the B16-F10 murine melanoma cell line as a model. Liposomes were obtained through reversed-phase evaporation by applying a spray dryer to assess their stability. The following biologic assays were measured cytotoxicity/antiproliferative (MTT, Neutral Red, and dsDNA PicoGreen). In addition, the levels of melanin and purinergic enzymes were also measured. The production of reactive oxygen species (ROS) and nitric oxide (NO) was determined as a measure of oxidative state. Treatment with nano-liposome containing alpha-arbutin induced a significant 68.4% cytotoxicity, similar to the positive control, in the B16-F10 murine melanoma cell line at 72 hr. Further, arbutin and liposomes containing alpha-arbutin increased levels of ROS and nitrite formation at 72 hr at the highest concentration (100 and 300 µg/ml) of treatments. Arbutin and liposomes containing alpha-arbutin reduced melanin levels at all tested concentrations. In addition, arbutin and alpha-arbutin containing liposomes lowered nucleotides (AMP, ADP, and ATP) and nucleoside (adenosine) levels in melanoma cells. Evidence suggests that α-arbutin containing liposome can be considered as an alternative immunosuppressive agent stimulated in melanoma treatment.

Nuciferine Alleviates High-Fat Diet- and ApoE-/--Induced Hepatic Steatosis and Ferroptosis in NAFLD Mice via the PPARα Signaling Pathway

Nonalcoholic fatty liver disease (NAFLD) causes significant global mortality and healthcare costs with no recommended pharmacological intervention for clinical management. Nuciferine (Nuc) is an alkaloid with aromatic rings, abundantly found in Nelumbo nucifera Gaertn. In this study, we explored the protective mechanisms of Nuc against hepatic steatosis and ferroptosis in NAFLD. High-fat diet (HFD) and healthy male ApoE-/- mice were used to induce NAFLD and a hypercholesterolemia model. Nuc was administered to the mice for four consecutive weeks from the ninth week. Various assessments, including histopathology, RNA sequencing, lipid metabolism, and ferroptosis-related protein expression, showed that Nuc alleviated hepatic steatosis and ferroptosis. We further showed that Nuc improves fatty acid accumulation and ferroptosis through the PPARα signaling pathway in mice and RSL3-treated AML-12 cells. The PPARα inhibitor GW6471 blocked Nuc's protective effects, leading to excess accumulation of iron ions. Thus, Nuc may be a potential therapeutic agent for NAFLD.

Scoulerine: A natural isoquinoline alkaloid targeting SLC6A3 to treat RCC

Scoulerine, an isoquinoline alkaloid derived from the corydalis plant, exhibits diverse therapeutic properties against tumors, Alzheimer's disease, and inflammation. This research delves into the pharmacological impact and underlying mechanism of scoulerine on renal cell carcinoma (RCC). Our findings suggest that Scoulerine displays promise as a potential therapeutic agent for RCC, demonstrating notable inhibitory effects in both in vivo and in vitro models. In addition, scoulerine inhibited the viability of 769-P and 786-O cell lines in a time-dependent and dose-dependent manner, and promoted the level of apoptosis associated with B-cell lymphoma-2 associated X protein (Bax). Moreover, the administration of scoulerine resulted in a significant suppression of the mitogen activated protein kinase (MAPK) signaling pathway. Subsequently, utilizing bioinformatics and spatial transcriptomic databases, we identified solute carrier family 6 Member 3 (SLC6A3) as the most promising target of scoulerine. Through experimental validation, we confirmed the functional and therapeutic relevance of SLC6A3 in scoulerine-mediated treatment of RCC. The results of our study indicate a significant affinity between scoulerine and SLC6A3, with competitive inhibition of this interaction leading to a reduction in the inhibitory impact of scoulerine on RCC cell viability. In conclusion, our findings suggest that scoulerine may induce apoptosis in RCC by targeting SLC6A3 and inhibiting the activation of the MAPK signaling pathway, thereby positioning it as a promising natural compound for potential future RCC treatment.

Deciphering heart failure: an integrated proteomic and transcriptomic approach with experimental validation

This study analyzed transcriptomic and proteomic data to identify molecular changes during heart failure (HF). Additionally,we embarked on an exploration of the prospect of therapeutic intervention through the manipulation of proteins implicated in ferroptosis. Three publicly available microarray datasets (GSE135055, GSE147236, GSE161472) profiling left ventricular samples from HF patients and healthy controls were obtained. Differentially expressed genes were identified in each dataset and cross-analyzed to determine shared gene signatures. Enrichment analysis of Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and gene set enrichment analysis were performed. Differentially expressed proteins were obtained from published proteomic studies and integrated with the transcriptomic results. To validate findings, a HF mouse model was generated and ferroptosis-related proteins were evaluated. Additionally, the effect of suppression of ferroptosis on hypoxia-induced ischemia model in HL-1 cardiomyocytes was assessed by knocking down Acyl-CoA synthetase long-chain family member 4 (ACSL4) using small interfering RNA (siRNA).Cross-analysis of differentially expressed genes (DEGs) in the GSE135055, GSE147236 and GSE161472 datasets revealed 224 up-regulated and 187 down-regulated potential genes which showed high enrichment in immune, inflammatory and metabolic pathways. Notably, four proteins, among them ACSL4, displayed consistent alterations at both the transcriptional and protein levels. In the HF mouse model, ACSL4 exhibited an elevation, whereas negative regulators of ferroptosis witnessed a decrement. Subsequently, knockdown of ACSL4 in a hypoxia-induced ischemic HL-1 cardiomyocyte cell model upregulated the expression of ferroptosis inhibitory protein and decreased the levels of reactive oxygen species (ROS), malondialdehyde (MDA)., and free iron and increased cell viability. Comprehensive multi-omics analysis revealed that the expression of the molecular target ACSL4 was increased in HF. Targeting ACSL4 to inhibit ferroptosis may represent a novel therapeutic strategy for HF treatment.

Ferroptosis promotes valproate-induced liver steatosis in vitro and in vivo

Valproic acid (VPA), a common antiepileptic drug, can cause liver steatosis after long-term therapy. However, an impact of ferroptosis on VPA-induced liver steatosis has not been investigated. In the study, treatment with VPA promoted ferroptosis in the livers of mice by elevating ferrous iron (Fe2+) levels derived from the increased absorption by transferrin receptor 1 (TFR1) and the decreased storage by ferritin (FTH1 and FTL), disrupting the redox balance via reduced levels of solute carrier family 7 member 11 (SLC7A11), glutathione (GSH), and glutathione peroxidase 4 (GPX4), and augmenting acyl-CoA synthetase long-chain family member 4 (ACSL4) -mediated lipid peroxide generation, accompanied by enhanced liver steatosis. All the changes were significantly reversed by co-treatment with an iron-chelating agent, deferoxamine mesylate (DFO) and a ferroptosis inhibitor, ferrostatin-1 (Fer-1). Similarly, the increases in Fe2+, TFR1, and ACSL4 levels, as well as the decreases in GSH, GPX4, and ferroportin (FPN) levels, were detected in VPA-treated HepG2 cells. These changes were also attenuated after co-treatment with Fer-1. It demonstrates that ferroptosis promotes VPA-induced liver steatosis through iron overload, inhibition of the GSH-GPX4 axis, and upregulation of ACSL4. It offers a potential therapy targeting ferroptosis for patients with liver steatosis following VPA treatment.

Ferroptosis at the nexus of metabolism and metabolic diseases

Ferroptosis, an iron-dependent form of regulated cell death, is emerging as a crucial regulator of human physiology and pathology. Increasing evidence showcases a reciprocal relationship between ferroptosis and dysregulated metabolism, propagating a pathogenic vicious cycle that exacerbates pathology and human diseases, particularly metabolic disorders. Consequently, there is a rapidly growing interest in developing ferroptosis-based therapeutics. Therefore, a comprehensive understanding of the intricate interplay between ferroptosis and metabolism could provide an invaluable resource for mechanistic insight and therapeutic development. In this review, we summarize the important metabolic substances and associated pathways in ferroptosis initiation and progression, outline the cascade responses of ferroptosis in disease development, overview the roles and mechanisms of ferroptosis in metabolic diseases, introduce the methods for ferroptosis detection, and discuss the therapeutic perspectives of ferroptosis, which collectively aim to illustrate a comprehensive view of ferroptosis in basic, translational, and clinical science.

Targeting cell death in NAFLD: mechanisms and targeted therapies

Nonalcoholic fatty liver disease (NAFLD) is a group of chronic liver disease which ranges from simple steatosis (NAFL) to non-alcoholic steatohepatitis (NASH) and is characterized by lipid accumulation, inflammation activation, fibrosis, and cell death. To date, a number of preclinical studies or clinical trials associated with therapies targeting fatty acid metabolism, inflammatory factors and liver fibrosis are performed to develop effective drugs for NAFLD/NASH. However, few therapies are cell death signaling-targeted even though the various cell death modes are present throughout the progression of NAFLD/NASH. Here we summarize the four types of cell death including apoptosis, necroptosis, pyroptosis, and ferroptosis in the NAFLD and the underlying molecular mechanisms by which the pathogenic factors such as free fatty acid and LPS induce cell death in the pathogenesis of NAFLD. In addition, we also review the effects of cell death-targeted therapies on NAFLD. In summary, our review provides comprehensive insight into the roles of various cell death modes in the progression of NAFLD, which we hope will open new avenues for therapeutic intervention.

Chenodeoxycholic Acid-Modified Polyethyleneimine Nano-Composites Deliver Low-Density Lipoprotein Receptor Genes for Lipid-Lowering Therapy by Targeting the Liver

Lipid-lowering drugs, especially statins, are extensively utilized in clinical settings for the prevention of hyperlipidemia. Nevertheless, prolonged usage of current lipid-lowering medications is associated with significant adverse reactions. Therefore, it is imperative to develop novel therapeutic agents for lipid-lowering therapy. In this study, a chenodeoxycholic acid and lactobionic acid double-modified polyethyleneimine (PDL) nanocomposite as a gene delivery vehicle for lipid-lowering therapy by targeting the liver, are synthesized. Results from the in vitro experiments demonstrate that PDL exhibits superior transfection efficiency compared to polyethyleneimine in alpha mouse liver 12 (AML12) cells and effectively carries plasmids. Moreover, PDL can be internalized by AML12 cells and rapidly escape lysosomal entrapment. Intravenous administration of cyanine5.5 (Cy5.5)-conjugated PDL nanocomposites reveals their preferential accumulation in the liver compared to polyethyleneimine counterparts. Systemic delivery of low-density lipoprotein receptor plasmid-loaded PDL nanocomposites into mice leads to reduced levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TC) in the bloodstream without any observed adverse effects on mouse health or well-being. Collectively, these findings suggest that low-density lipoprotein receptor plasmid-loaded PDL nanocomposites hold promise as potential therapeutics for lipid-lowering therapy.

Targeting the regulation of iron homeostasis as a potential therapeutic strategy for nonalcoholic fatty liver disease

With aging and the increasing incidence of obesity, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. NAFLD mainly includes simple hepatic steatosis, nonalcoholic steatohepatitis (NASH), liver fibrosis and hepatocellular carcinoma (HCC). An imbalance in hepatic iron homeostasis is usually associated with the progression of NAFLD and induces iron overload, reactive oxygen species (ROS) production, and lipid peroxide accumulation, which leads to ferroptosis. Ferroptosis is a unique type of programmed cell death (PCD) that is characterized by iron dependence, ROS production and lipid peroxidation. The ferroptosis inhibition systems involved in NAFLD include the solute carrier family 7 member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1)/coenzyme Q10 (CoQ10)/nicotinamide adenine dinucleotide phosphate (NADPH) regulatory axes. The main promotion system involved is the acyl-CoA synthetase long-chain family (ACSL4)/arachidonic lipoxygenase 15 (ALOX15) axis. In recent years, an increasing number of studies have focused on the multiple roles of iron homeostasis imbalance and ferroptosis in the progression of NAFLD. This review highlights the latest studies about iron homeostasis imbalance- and ferroptosis-associated NAFLD, mainly including the physiology and pathophysiology of hepatic iron metabolism, hepatic iron homeostasis imbalance during the development of NAFLD, and key regulatory molecules and roles of hepatic ferroptosis in NAFLD. This review aims to provide innovative therapeutic strategies for NAFLD.

Insight into the regulatory mechanism of m6A modification: From MAFLD to hepatocellular carcinoma

In recent years, there has been a significant increase in the incidence of metabolic-associated fatty liver disease (MAFLD), which has been attributed to the increasing prevalence of type 2 diabetes mellitus (T2DM) and obesity. MAFLD affects more than one-third of adults worldwide, making it the most prevalent liver disease globally. Moreover, MAFLD is considered a significant risk factor for hepatocellular carcinoma (HCC), with MAFLD-related HCC cases increasing. Approximately 1 in 6 HCC patients are believed to have MAFLD, and nearly 40 % of these HCC patients do not progress to cirrhosis, indicating direct transformation from MAFLD to HCC. N6-methyladenosine (m6A) is commonly distributed in eukaryotic mRNA and plays a crucial role in normal development and disease progression, particularly in tumors. Numerous studies have highlighted the close association between abnormal m6A modification and cellular metabolic alterations, underscoring its importance in the onset and progression of MAFLD. However, the specific impact of m6A modification on the progression of MAFLD to HCC remains unclear. Can targeting m6A effectively halt the progression of MAFLD-related HCC? In this review, we investigated the pivotal role of abnormal m6A modification in the transition from MAFLD to HCC, explored the potential of m6A modification as a therapeutic target for MAFLD-related HCC, and proposed possible directions for future investigations.

Unveiling the role of ferroptosis in the progression from NAFLD to NASH: recent advances in mechanistic understanding

Non-alcoholic fatty liver disease (NAFLD) is a prevalent and significant global public health issue. Nonalcoholic steatohepatitis (NASH) represents an advanced stage of NAFLD in terms of pathology. However, the intricate mechanisms underlying the progression from NAFLD to NASH remain elusive. Ferroptosis, characterized by iron-dependent cell death and distinguished from other forms of cell death based on morphological, biochemical, and genetic criteria, has emerged as a potential participant with a pivotal role in driving NAFLD progression. Nevertheless, its precise mechanism remains poorly elucidated. In this review article, we comprehensively summarize the pathogenesis of NAFLD/NASH and ferroptosis while highlighting recent advances in understanding the mechanistic involvement of ferroptosis in NAFLD/NASH.

Ferroptosis inhibitors: past, present and future

Ferroptosis is a non-apoptotic mode of programmed cell death characterized by iron dependence and lipid peroxidation. Since the ferroptosis was proposed, researchers have revealed the mechanisms of its formation and continue to explore effective inhibitors of ferroptosis in disease. Recent studies have shown a correlation between ferroptosis and the pathological mechanisms of neurodegenerative diseases, as well as diseases involving tissue or organ damage. Acting on ferroptosis-related targets may provide new strategies for the treatment of ferroptosis-mediated diseases. This article specifically describes the metabolic pathways of ferroptosis and summarizes the reported mechanisms of action of natural and synthetic small molecule inhibitors of ferroptosis and their efficacy in disease. The paper also describes ferroptosis treatments such as gene therapy, cell therapy, and nanotechnology, and summarises the challenges encountered in the clinical translation of ferroptosis inhibitors. Finally, the relationship between ferroptosis and other modes of cell death is discussed, hopefully paving the way for future drug design and discovery.

Examining the Pathogenesis of MAFLD and the Medicinal Properties of Natural Products from a Metabolic Perspective

Metabolic-associated fatty liver disease (MAFLD), characterized primarily by hepatic steatosis, has become the most prevalent liver disease worldwide, affecting approximately two-fifths of the global population. The pathogenesis of MAFLD is extremely complex, and to date, there are no approved therapeutic drugs for clinical use. Considerable evidence indicates that various metabolic disorders play a pivotal role in the progression of MAFLD, including lipids, carbohydrates, amino acids, and micronutrients. In recent years, the medicinal properties of natural products have attracted widespread attention, and numerous studies have reported their efficacy in ameliorating metabolic disorders and subsequently alleviating MAFLD. This review aims to summarize the metabolic-associated pathological mechanisms of MAFLD, as well as the natural products that regulate metabolic pathways to alleviate MAFLD.