Regulation of cholesterol homeostasis in health and diseases: from mechanisms to targeted therapeutics

Integrating 16S rDNA sequencing analysis and targeted metabolomics to explore the mechanism of Xiexin Tang in treating atherosclerosis mice induced by high-fat diet

Xiexin Tang (XXT) is a classic Chinese medicine formula that can be used to treat Atherosclerosis (AS). This study aimed to investigate the mechanism by which XXT regulated AS lipid levels. Firstly, the mixture components of XXT were analyzed by High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Then, the AS model based on Apolipoprotein E knockout (ApoE-/-) mice was established. Cytokines related to lipid metabolism and bile acid metabolism were detected by Quantitative Real-time PCR (qRT-PCR). 16S rDNA gene sequencing was performed to analyze differential bacterial populations, and the mechanism of XXT regulation of bile acids affecting lipid metabolism was further explored by targeted metabolomics. Further, antibiotic-treated mice were used to investigate the role of gut microbiota in the anti-AS effect of XXT. The results showed that XXT attenuated the lipid levels and reversed the abnormal elevation of cytokines, such as hepatic lipid metabolism and inflammatory reaction in AS mice. XXT also repaired the gut barrier damage and reversed gut microbiota disorders in AS mice. Furthermore, the metabolic levels of bile acids were reshaped by XXT. Whereas, in the absence of gut microbiota, XXT failed to attenuate lipid levels and inhibit the expression of cytokines related to inflammation and bile acid metabolism in AS mice and failed to play a role in ultimately treating AS. In conclusion, XXT could effectively inhibit the inflammatory reaction and lipid accumulation in AS mice, and this effect was closely related to its remodeling of gut microbiota to regulate bile acid metabolism.

RNA therapeutics in cardiovascular medicine

PURPOSE OF REVIEW

RNA therapeutics came to global attention when mRNA-based vaccines provided an answer to the SARS-CoV-2 pandemic. The immense significance of this development notwithstanding, it is important to note that almost a decade prior to the pandemic, RNA drugs had made important inroads toward the amelioration of disease. The first class of RNA therapies to be introduced into clinical use were the antisense oligomers and siRNA drugs which generally induce a therapeutic effect by acting to brake or to modulate mRNA expression. RNA therapeutics is quickly becoming the fourth pillar of pharmacotherapy, and will have broad applications, including for the treatment of cardiovascular disease.

RECENT FINDINGS

The United States (US) Food and Drug Administration (FDA) has approved several antisense oligomers (ASOs) and siRNA-based drugs to treat disorders associated with cardiovascular disease. In addition, multiple RNA-based drugs are in clinical trials to assess their safety and efficacy in patients with cardiovascular disorders, such as Zodasiran, a siRNA therapy that targets angiopoietin-like protein 3 (ANGPTL3) to reduce LDL cholesterol.

SUMMARY

Because of limitless sequence choice; speed of design; and relative ease of synthesis, RNA drugs will be rapidly developed, will have broad applications, and will be generated at lower cost than other drug types. This review aims to highlight RNA therapies for cardiovascular diseases that are approved, and those that are under clinical evaluation.

Unraveling the link between cholesterol and immune system in cancer: From biological mechanistic insights to clinical evidence. A narrative review

Cholesterol and its metabolism seem to be involved not only in cancer progression but also in immune cells activity. In this comprehensive review, we summarize preclinical, translational, and clinical evidence regarding the crucial role of cholesterol and its metabolism in regulating the immune response against cancer cells, shedding light on the multifaceted mechanisms by which cholesterol influences immune cell function and anti-tumor immunity. By synthesizing findings from preclinical studies, we have elucidated the impact of cholesterol on immune cell activation, differentiation, and effector functions. These investigations have revealed that cholesterol metabolism plays a pivotal role in shaping the immune response, with alterations in cholesterol levels directly impacting immune cell behavior and anti-tumor activity. All the steps related to cholesterol metabolism, including its de-novo synthesis, its influx and efflux mechanisms, as well as its metabolites, have a distinct impact on immune cells function and activity, which, if altered, might influence tumor progression. In addition, we have reviewed clinical studies investigating the role of circulating cholesterol on outcomes of patients with advanced tumors treated with immune checkpoint inhibitors, highlighting again in a clinical scenario the correlation between cholesterol and the immune system. Overall, our review emphasizes the importance of cholesterol and its metabolism in orchestrating the immune response against cancer cells. Herein we have provided a comprehensive overview of this emerging field by illustrating the intricate interplay between cholesterol and immune system.

Fangchinoline suppresses nasopharyngeal carcinoma progression by inhibiting SQLE to regulate the PI3K/AKT pathway dysregulation

BACKGROUND AND PURPOSE

Squalene epoxidase (SQLE), a key enzyme in cholesterol metabolism, remains underexplored in nasopharyngeal carcinoma (NPC). Additionally, the therapeutic potential of Fangchinoline, an alkaloid with anticancer properties, has yet to be systematically evaluated. This research investigates Fangchinoline's efficacy in NPC treatment and SQLE-related mechanisms.

METHODS

Drug screening in NPC cell lines C666-1 and 5-8F identified potential candidates. IC50 values were determined using CCK-8 assays, and apoptosis, proliferation, and invasion were assessed via Annexin V/PI staining, EdU staining, and Transwell assays. Cholesterol levels were quantified using a TG kit. RNA sequencing with GO/KEGG analyses identified key pathways. Correlation analysis was performed via cBioPortal and GEPIA2 databases, protein interaction networks via STRING and Cytoscape, and survival analysis via Kaplan-Meier curves. Gene and protein expression were validated with qPCR and Western blot, and an NPC mouse model confirmed in vivo efficacy.

RESULTS

Fangchinoline inhibited NPC cell proliferation, induced apoptosis, and reduced cholesterol accumulation. RNA sequencing revealed that Fangchinoline downregulated SQLE expression, suppressing the PI3K/AKT pathway. Correlation and protein interaction analyses highlighted SQLE's role in NPC progression, and survival analysis confirmed its clinical relevance. By targeting SQLE and disrupting cholesterol metabolism, Fangchinoline suppressed tumor growth both in vitro and in vivo.

CONCLUSION

Our study demonstrates that Fangchinoline inhibits NPC growth by targeting SQLE and disrupting the PI3K/AKT pathway, providing new insights into SQLE as a therapeutic target in NPC.

Cholesterol crystals in the pathogenesis of atherosclerosis

The presence of cholesterol crystals (CCs) in tissues was first described more than 100 years ago. CCs have a pathogenic role in various cardiovascular diseases, including myocardial infarction, aortic aneurysm and, most prominently, atherosclerosis. Although the underlying mechanisms and signalling pathways involved in CC formation are incompletely understood, numerous studies have highlighted the existence of CCs at various stages of atheroma progression. In this Review, we summarize the mechanisms underlying CC formation and the role of CCs in cardiovascular disease. In particular, we explore the established links between lipid metabolism across various cell types and the formation of CCs, with a focus on CC occurrence in the vasculature. We also discuss CC-induced inflammation as one of the pathogenic features of CCs in the atheroma. Finally, we summarize the therapeutic strategies aimed at reducing CC-mediated atherosclerotic burden, including approaches to inhibit CC formation in the vasculature or to mitigate the inflammatory response triggered by CCs. Addressing CC formation might emerge as a crucial component in our broader efforts to combat cardiovascular disease.

MAIT Cells Promote Cholesterol Excretion Pathways Mitigating Atherosclerosis

BACKGROUND

Previous clinical studies have indicated reduced circulating mucosal-associated invariant T (MAIT) cells in individuals with coronary artery disease. However, the precise role and underlying mechanisms of MAIT cells in this context remain unclear. Immune homeostasis plays a pivotal role in the development of atherosclerosis. This study explores the impact of MAIT cells on atherosclerosis.

METHODS

Vα19+/- Ldlr-/- mice, characterized by a high MAIT cell frequency, and MAIT cell deficient MR1-/- (major histocompatibility complex-related molecule 1) Ldlr-/- mice and their respective controls were used. Starting at 6 weeks of age, mice were subjected to a 1% cholesterol diet for 16 weeks. Additionally, the study analyzed circulating MAIT cell frequency and cholesterol levels in 68 patients with hypercholesterolemia.

RESULTS

In Vα19+/- Ldlr-/- mice, increased MAIT cells demonstrated a protective effect against atherosclerosis by reducing VLDL-C (very-low-density lipoprotein cholesterol) levels through heightened cholesterol excretion. This effect was accompanied by elevated jejunal ABCB1a, ABCG5, and ABCG8 expression, mediated by augmented levels of Liver X receptor transcription and activation, likely through intestinal IL-22 (interleukin-22) signaling. Conversely, cholesterol reduction mediated by intestinal cholesterol excretion was blocked by inhibition of MAIT cells. Moreover, MAIT cell-deficient MR1-/- Ldlr-/- mice exhibited elevated total cholesterol levels and increased atherosclerotic lesions. In patients with hypercholesterolemia, circulating MAIT cell frequency displayed negative correlations with VLDL-C levels and positive correlations with HDL-C (high-density lipoprotein cholesterol) levels.

CONCLUSIONS

Our findings demonstrate a new mechanism for plasma VLDL-C clearance by MAIT cell-mediated cholesterol excretion. The results provide further evidence that immunity is involved in cholesterol homeostasis. Targeting intestinal immunity to regulate cholesterol homeostasis holds promise as a new cholesterol-lowering modality to prevent atherosclerotic cardiovascular disease.

Cyclodextrin-Derived Macromolecular Therapies for Inflammatory Diseases

Inflammation is an essential physiological defense mechanism against harmful stimuli, yet dysregulated inflammatory responses are closely associated with the pathogenesis of numerous acute and chronic diseases. Recent advances highlight the remarkable anti-inflammatory potential of bioactive macromolecules, particularly cyclodextrins (CDs) and their engineered derivatives, which are emerging as promising therapeutic agents. This review systematically introduces different CDs and CD-derived macromolecules that demonstrate anti-inflammatory properties, with emphasis on their molecular mechanisms of action. Native CDs exhibit direct therapeutic effects through host-guest interactions, enabling selective sequestration of pathogenic components such as cholesterol crystals and proteins that drive inflammatory cascades. Moreover, chemically modified CD derivatives incorporating functional groups demonstrate enhanced capabilities in neutralizing inflammatory mediators and modulating immune cell responses. This work further discusses the expanding therapeutic applications of these macromolecules across diverse inflammatory conditions, ranging from acute tissue injuries to chronic autoimmune disorders. Finally, this work critically analyzes the crucial challenges and emerging opportunities in translating CD-based macromolecular therapies into clinical practice, addressing key considerations in biocompatibility, targeted delivery, and therapeutic efficacy optimization.

Lipid metabolism dysregulation for bone metastasis and its prevention

INTRODUCTION

Bone metastasis often develops in advanced malignancies. Lipid metabolic dysregulation might play pivotal role in cancer progression and subsequent deterioration of bone health at metastatic condition. In-depth understanding of lipid reprogramming in metastasized cancer cells and other stromal cells including bone marrow adipocyte (BMA) is an urgent need to develop effective therapy.

AREA COVERED

This paper emphasizes providing an overview of multifaceted role of dysregulated lipids and BMA in cancer cells in association with bone metastasis by utilizing search terms lipid metabolism, lipid and metastasis in PubMed. This study extends to address mechanism linked with lipid metabolism and various crucial genes (e.g. CSF-1, RANKL, NFkB and NFATc1) involved in bone metastasis. This review examines therapeutic strategies targeting lipid metabolism to offer potential avenues to disrupt lipid-driven metastasis.

EXPERT OPINION

On metastatic condition, dysregulated lipid molecules especially in BMA and other stromal cells not only favors cancer progression but also potentiate lipid reprogramming within cancer cells. Distinct dysregulated lipid-metabolism associated genes may act as biomarker, and targeting these is challenging task for specific treatment. Curbing function of bone resorption associated genes by lipid controlling drugs (e.g. statins, omega-3 FA and metformin) may provide additional support to curtail lipid-associated bone metastasis.

Quantity and meal timing of dietary cholesterol intake and cerebrovascular disease mortality

Background: Recent guidelines have removed specific limitations of dietary cholesterol, which has raised considerable debate regarding the significance of cholesterol in the context of cerebrovascular disease (CBD). Furthermore, the relationship between the quantity and meal timing of dietary cholesterol intake and CBD mortality remains unclear. This study aims to explore the relationships between the quantity and meal timing of dietary cholesterol intake and CBD mortality among older adults using the U.S. National Health and Nutrition Examination Survey (NHANES) (2003-2018). Methods: In this prospective study of 7906 older adults aged over 50 years in the National Health and Nutrition Examination Survey (2003-2018), dietary intake was divided into quintiles, and meal timing was evaluated using two days of 24-hour dietary recall. Serum cholesterol levels were measured. The relationship between the quantity and meal timing of dietary cholesterol and mortality was examined with survey-weighted Cox regression models. Results: During a follow-up of 15 years, 107 participants died of CBD. Compared with participants with the lowest quintile of total cholesterol intake (CHO-T) and cholesterol at breakfast (CHO-B), no significant association between CHO-T and CHO-B and mortality (HRCHO-T 0.48; 95%CI 0.18-1.23 and HRCHO-B 0.98; 95%CI 0.37-2.47) was observed. For the difference of cholesterol at dinner (CHO-D) minus CHO-B (ΔCHO), which was related to lower CBD mortality (HR 0.45; 95%CI 0.21-0.97), 29-142 mg of ΔCHO was associated with lower CBD mortality in a non-linear manner and 29-112 mg of ΔCHO was associated with lower TC and LDL-C levels. Conclusions: Moderate consumption of dietary cholesterol at dinner rather than breakfast was associated with a lower risk of CBD mortality in a nonlinear manner, whereas the total quantity of dietary cholesterol throughout the day was not associated with CBD mortality.

Urbanization's hidden influence: Linking landscape alterations and feather coloration with pigeon's cholesterol levels

Urbanization significantly impacts synanthropic birds, influencing their physiology and appearance. For instance, urban environments are associated with higher plasma cholesterol levels in birds due to human-derived food sources. Additionally, landscape changes create environmental pressures, which favor more melanic plumages. Current evidence suggests that urbanization may influence bird cholesterol through mechanisms beyond diet, possibly via the pleiotropic effects of the melanocortin system. In this study, we examine how cholesterolemia varies in urban pigeons (Columba livia), a species with polymorphic plumage, across different levels of urbanization and degrees of melanism. To investigate this, we analyzed pigeons along urbanization gradients and sampled birds from various locations in Santiago, a South American metropolis. Plumage color was characterized using image analysis, and the expression of the MITF and MC1R genes in the skin was measured. Blood samples were analyzed for biochemical parameters, genetic sex determination, and nitrogen isotopic signatures (δ15N) in red blood cells. We found correlations between human-induced spatial heterogeneity indexes (e.g., Impervious Surface, Global Human Modification, and Land Surface Temperature) and plumage melanism. However, no direct relationship was found between these landscape features and cholesterol levels, although there were links to glucose and triglycerides. Interestingly, plasma cholesterol levels strongly correlated with plumage melanism features independent of δ15N, suggesting a non-trophic origin of elevated cholesterol. Furthermore, we identified and quantified the indirect effects of urbanization on cholesterolemia using structural equation modeling. This evidence highlights the interplay between urban stressors and bird melanism, underscoring the importance of pleiotropic phenomena in socio-eco-evolutionary dynamics of urban ecosystems.

Cth/Mpst double ablation results in early onset fatty liver disease in lean mice

Metabolic dysfunction-associated fatty liver disease (MAFLD), a condition that stems from hepatic lipid accumulation in the absence of liver damage and overt inflammation, has become the most common hepatic disorder worldwide. Hydrogen sulfide (H2S), a gasotrasmitter, endogenously generated mainly by cystathionine-γ lyase (CTH), cystathionine-β synthase (CBS) and 3-mercaptopyruvate sulfurtransferase (MPST) enzymes, exhibits protective effect in steatosis. Herein, we have demonstrated that CTH and MPST play a central role in MAFLD pathogenesis. Young Cth/Mpst knockout (Cth/Mpst-/-) mice, fed a normal diet, had increased liver mass caused by enhanced hepatic lipid accumulation. Decreased insulin and glucose sensitivity was observed in CTH/MPST-deficient mice. At the cellular level, CTH/MPST inhibition resulted in increased lipid deposition and glucose uptake in hepatocytes. Transcriptome analysis revealed significant upregulation of cholesterol biosynthesis and SREBP-related genes in the liver of Cth/Mpst-/- mice. Transcription factor enrichment analysis of differentially expressed genes between two genotypes, revealed a major impact of LXR, RXR and PPARA in the observed phenotype. Sulfide donor (SG1002) treatment attenuated the fatty liver disease of CTH/MPST-deficient mice. Our findings underline the importance of endogenously produced H2S in the pathogenesis of MAFLD and introduce the Cth/Mpst-/- mouse as a new animal model of early onset hepatic steatosis.

Aspergillus fumigatus secondary metabolite pyripyropene is important for the dual biofilm formation with Pseudomonas aeruginosa

The human pathogenic fungus Aspergillus fumigatus establishes dual biofilm interactions in the lungs with the pathogenic bacterium Pseudomonas aeruginosa. Screening of 21 A. fumigatus null mutants revealed seven mutants (two G protein-coupled receptors, three mitogen-activated protein kinase receptors, a Gα protein, and one histidine kinase receptor) with reduced biofilm formation, specifically in the presence of P. aeruginosa. Transcriptional profiling and metabolomics analysis of secondary metabolites produced by one of these mutants, ΔgpaB (gpaB encodes a Gα protein), showed GpaB controls the production of several important metabolites for the dual biofilm interaction, including pyripyropene A, a potent inhibitor of mammalian acyl-CoA cholesterol acyltransferase. Deletion of pyr2, encoding a non-reducing polyketide synthase essential for pyripyropene biosynthesis, showed reduced A. fumigatus Δpyr2-P. aeruginosa biofilm growth, altered macrophage responses, and attenuated mouse virulence in a chemotherapeutic murine model. We identified pyripyropene as a novel player in the ecology and pathogenic interactions of this important human fungal pathogen.IMPORTANCEAspergillus fumigatus and Pseudomonas aeruginosa are two important human pathogens. Both organisms establish biofilm interactions in patients affected with chronic lung pulmonary infections, such as cystic fibrosis (CF) and chronic obstructive pulmonary disease. Colonization with A. fumigatus is associated with an increased risk of P. aeruginosa colonization in CF patients, and disease prognosis is poor when both pathogens are present. Here, we identified A. fumigatus genetic determinants important for the establishment of in vitro dual A. fumigatus-P. aeruginosa biofilm interactions. Among them, an A. fumigatus Gα protein GpaB is important for this interaction controlling the production of the secondary metabolite pyripyropene. We demonstrate that the lack of pyripyropene production decreases the dual biofilm interaction between the two species as well as the virulence of A. fumigatus in a chemotherapeutic murine model of aspergillosis. These results reveal a complete novel role for this secondary metabolite in the ecology and pathogenic interactions of this important human fungal pathogen.

Cholesterol-modifying strategies for Alzheimer disease: promise or fallacy?

INTRODUCTION

As the world population ages, Alzheimer disease (AD) prevalence increases. However, understanding of AD etiology continues to evolve, and the pathophysiological processes involved are only partially elucidated. One compound suspected to play a role in the development and progression of AD is cholesterol. Several lines of evidence support this connection, yet it remains unclear whether cholesterol-modifying strategies have potential applications in the clinical management of AD.

AREAS COVERED

A deep literature search using PubMed was performed to prepare this narrative review. The literature search, performed in early 2024, was inclusive of literature from 1990 to 2024. After providing an overview of cholesterol metabolism, this study summarizes key preclinical studies that have investigated cholesterol-modifying therapies in laboratory models of AD. It also summarizes past and current clinical trials testing specific targets modulated by anti-cholesterol therapies in AD patients.

EXPERT OPINION

Based on current epidemiological and mechanistic studies, cholesterol likely plays a role in AD etiology. The use of cholesterol-modifying therapies could be a promising treatment approach if administered at presymptomatic to early AD phases, but it is unlikely to be efficient in mild, moderate, and late AD stages. Several recommendations are provided for hypercholesterolemia management in AD patients.

Geniposidic Acid Targeting FXR "S332 and H447" Mediated Conformational Change to Upregulate CYPs and miR-19a-3p to Ameliorate Drug-Induced Liver Injury

Drug-induced liver injury (DILI), caused by chemical drugs and traditional Chinese medicine, often leads to severe outcomes like liver failure due to a lack of early detection markers. Farnesoid X receptor (FXR), a key regulator of bile acid (BA) and cholesterol metabolism, is a potential therapeutic target. This study investigates the pathogenesis, markers, and treatment strategies for DILI, focusing on the hepatoprotective effects of geniposidic acid (GPA) from Gardenia jasminoides J. Ellis. Using cellular and animal models of acute and chronic DILI induced by acetaminophen and triptolide, we explored GPA's mechanisms in BA and cholesterol metabolism. Lipidomic and BA analyses revealed that GPA alleviates DILI by enhancing bile acid synthesis and transport via FXR activation. Experiments using AAV-shFXR, Fxr- / - mice and molecular assays demonstrated that GPA targets Ser332 and His447 on FXR ligand-binding domain, promoting FXR nuclear translocation and initiating cytochrome P450 proteins (CYPs) transcriptional activation for BA metabolism. Additionally, miRNA sequencing and RNA-pulldown assays showed that GPA-activated FXR upregulates miR-19a-3p, binding to LXR 3'UTR to inhibit cholesterol production. These findings reveal the GPA-FXR "structure-target" relationship, highlighting a dual mechanism in which GPA promotes CYPs-mediated bile acid metabolism and miR-19a-3p-mediated cholesterol synthesis inhibition, providing a basis for FXR-targeted DILI therapies.

Lipid-targeting antiviral strategies: Current state and future perspectives

There is an urgent need for antiviral compounds effective against currently known and future viral threats. The development of host-targeting antivirals (HTAs) appears as an alternative strategy to fight viral infections minimizing the potential of resistant mutant development and potentially leading to the identification of broad-spectrum antiviral agents. Among the host factors explored for HTA strategy, lipids constitute an attractive target as many viruses, even genetically diverse, hijack specific lipids during their lifecycle. Multiple repurposing efforts have been performed to analyze the antiviral properties of lipid-targeting compounds. These studies include the analysis of the effects of cholesterol lowering drugs such as statins, cholesterol transport inhibitors, sphingolipid modulators, de novo lipogenesis inhibitors blocking fatty acid synthesis, compounds targeting glycerophospholipids or drugs interfering with lipid droplet metabolism. This review is focused on the current status of lipid-based or lipid-targeting antiviral strategies and their potential for the development of antiviral therapies, with special emphasis on those studies that have reached advanced stages of development such as efficacy studies in animal models or clinical trials. Whereas there is still a long way to go, multiple proof-of-concept studies and clinical evidence reinforce the therapeutic potential of these strategies warranting their further development into effective antiviral therapies.

High-frequency ultrasound induced the preparation of oxidized low density lipoprotein

Foam cells have been frequently used in studies related to atherosclerosis. Traditional methods for inducing oxidized low-density lipoprotein (oxLDL) involve copper ion (Cu2+) treatment, which has inherent limitations such as prolonged oxidation times and residual copper ions. This study explored high-frequency ultrasound (400 kHz) as an alternative method for LDL oxidization. The findings demonstrated that high-frequency ultrasound-oxidized LDL (U-oxLDL) exhibited no significant differences compared to copper-oxidized LDL (Cu-oxLDL) in terms of electrophoretic mobility, foam cell morphology, lipid content, and cholesterol transport proteins. Additionally, lipidomic analysis revealed that U-oxLDL was more comparable to native LDL (N-LDL). Transcriptomic profiling of bone marrow-derived macrophages (BMDMs) treated with oxLDL showed that the gene expression patterns of BMDM foam cells treated with U-oxLDL were over 90 % consistent with those treated with Cu-oxLDL. Therefore, high-frequency ultrasound oxidation method represents a green and efficient strategy for oxLDL preparation, offering potential advantages for advancing atherosclerosis research.

Swimming exercise induces redox-lipid crosstalk to ameliorate osteoarthritis progression

Conventional pharmacotherapy exhibits limited efficacy in halting cartilage degeneration, whereas exercise interventions have demonstrated promising protective effects against osteoarthritis (OA), albeit with unclear underlying mechanisms. This study investigated the beneficial effects of swimming in mitigating local joint damage through the enhancement of systemic antioxidant capacity. We found that overexpression of superoxide dismutase 3 (SOD3) could promote the elimination of extracellular reactive oxygen species (ROS) and preserve the cartilage extracellular matrix (C-ECM). Conversely, genetic deletion of SOD3 accelerated the loss of C-ECM and contributed to OA due to an imbalance in extracellular oxidative stress. Further investigation revealed that SOD3 could interact with CCAAT/enhancer binding protein β (C/EBPβ), leading to the inhibition of apolipoprotein E (APOE) transcription and subsequent APOE-induced cholesterol transport. Ultimately, we developed targeted extracellular vesicles (EVs) with high cartilage affinity for efficient and precise delivery of SOD3. Overall, this study elucidated the potential of exercise for degenerative joint disorders through SOD3-mediated extracellular antioxidation and cholesterol redistribution.

The Role of Cholesterol Metabolism and Its Regulation in Tumor Development

BACKGROUND

Within the tumor microenvironment, tumor cells undergo metabolic reprogramming of cholesterol due to intrinsic cellular alterations and changes in the extracellular milieu. Furthermore, cholesterol reprogramming within this microenvironment influences the immune landscape of tumors, facilitating immune evasion and consequently promoting tumorigenesis. These biological changes involve modifications in numerous enzymes associated with cholesterol uptake and synthesis, including NPC1L1, SREBP, HMGCR, SQLE, and PCSK9.

REVIEW

This review systematically summarizes the role of cholesterol metabolism and its associated enzymes in cancer progression, examines the mechanisms through which dysregulation of cholesterol metabolism affects immune cells within the tumor microenvironment, and discusses recent advancements in cancer therapies that target cholesterol metabolism.

CONCLUSION

Targeting cholesterol metabolism-related enzymes can inhibit tumor growth, reshape immune landscapes, and rejuvenate antitumor immunity, offering potential therapeutic avenues in cancer treatment.

LOX-1 rewires glutamine ammonia metabolism to drive liver fibrosis

OBJECTIVE

Liver fibrosis is a crucial condition for evaluating the prognosis of chronic liver disease. Lectin-1ike oxidized low density lipoprotein receptor-1 (LOX-1) has been shown potential research value and therapeutic targeting possibilities in different fibrotic diseases. However, the role of LOX-1 and the underlying mechanisms in liver fibrosis progression remain unclear.

METHODS

LOX-1 expression was detected in liver tissues from patients and rodents with liver fibrosis. LOX-1 knockout rats were subjected to CCl4 or methionine and choline-deficient diet (MCD) to induce liver fibrosis. Transcriptomic and metabolomics analysis were used to investigate the involvement and mechanism of LOX-1 on liver fibrosis.

RESULTS

We found that LOX-1 exacerbated liver fibrosis by promoting hepatic stellate cells (HSCs) activation. LOX-1 deletion reversed the development of liver fibrosis. We further verified that LOX-1 drove liver fibrosis by reprogramming glutamine metabolism through mediating isoform switching of glutaminase (GLS). Mechanistically, we revealed the crucial role of the LOX-1/OCT1/GLS1 axis in the pathogenesis of liver fibrosis. Moreover, LOX-1 rewired ammonia metabolism by regulating glutamine metabolism-urea cycle to drive the progression of liver fibrosis.

CONCLUSIONS

Our findings uncover the pivotal role of LOX-1 in the progression of liver fibrosis, enrich the pathological significance of LOX-1 regulation of hepatic ammonia metabolism, and provide an insight into promising targets for the therapeutic strategy of liver fibrosis, demonstrating the potential clinical value of targeting LOX-1 in antifibrotic therapy.

Treatment of Pathological Lymphangiogenesis via Circular RNA-Mediated Cholesterol Metabolism Remodeling

Purpose

Lymphangiogenesis plays important roles in the pathogenesis of human diseases, including inflammatory ocular diseases, metabolic diseases, and cancers, by affecting lipid metabolism and immune homeostasis. Despite growing evidence showing that circular RNAs (circRNAs) act as the regulators of inflammatory and metabolic pathways, their roles in lymphatic dysfunction remain unclear. This study aims to explore the involvement of circRNA-KIF6 (cKIF6) in pathological lymphangiogenesis and elucidate the underlying mechanism.

Methods

The cKIF6 expression was evaluated in mouse-sutured corneas and lymphatic endothelial cells (LECs) isolated from juvenile foreskin under inflammatory conditions. Functional assays, including viability, proliferation, migration, and tube formation, were conducted on LECs after cKIF6 silencing. Lymphangiogenesis was evaluated using mouse-sutured cornea and Matrigel plug models. Mechanistic studies explored the role of cKIF6 as a molecular sponge for miR-582 and its downstream effect on methylsterol monooxygenase 1 (MSMO1).

Results

The cKIF6 expression was significantly elevated in mouse-sutured corneas and inflamed LECs. Silencing cKIF6 impaired LEC viability, proliferation, migration, and tube formation, leading to reduced lymphangiogenesis in both in vitro and in vivo models. Mechanistically, cKIF6 acted as a miR-582 sponge, resulting in elevated MSMO1 expression and increased cholesterol content in LECs. The augmented proliferation, migration, and tube formation abilities of cKIF6-overexpressing LECs were attenuated by the inhibitor of cholesterol biosynthesis.

Conclusions

The cKIF6 regulates lymphangiogenesis by targeting cholesterol metabolism, making it a promising therapeutic target for lymphangiogenesis-related diseases.

CD4+ T-cell metabolism in the pathogenesis of Sjogren's syndrome

The abnormal effector function of CD4+ T cells plays a key role in the pathogenesis of Sjogren's syndrome (SS) and its associated systematic autoimmune response. Cellular metabolism, including glucose metabolism, lipid metabolism and amino acid metabolism, supports proliferation, migration, survival and differentiation into distinct CD4+ T-cell subsets. Different subtypes of T cells have significantly different demands for related metabolic processes, which enables us to finely regulate CD4+ T cells through different metabolic processes in autoimmune diseases such as SS. In this review, we summarize the effects of disturbances in distinct metabolic processes, such as glycolysis, fatty acid metabolism, glutamine decomposition, mitochondrial dynamics, and ferroptosis, on how to support the effector functions of CD4+ T cells in the SS. We also discuss potential drugs with high value in the treatment of SS through metabolic normalization in CD4+ T cells. Finally, we propose possible directions for future targeted therapy for immunometabolism in SS.

Structural basis for cholesterol sensing of LYCHOS and its interaction with indoxyl sulfate

The lysosome serves as an essential nutrient-sensing hub within the cell, where the mechanistic target of rapamycin complex 1 (mTORC1) is activated. Lysosomal cholesterol signaling (LYCHOS), a lysosome membrane protein, has been identified as a cholesterol sensor that couples cholesterol concentration to mTORC1 activation. However, the molecular basis is unknown. Here, we determine the cryo-electron microscopy (cryo-EM) structure of human LYCHOS at a resolution of 3.1 Å, revealing a cholesterol-like density at the interface between the permease and G-protein coupled receptor (GPCR) domains. Advanced 3D classification reveals two distinct states of LYCHOS. Comparative structural analysis between these two states demonstrated a cholesterol-related movement of GPCR domain relative to permease domain, providing structural insights into how LYCHOS senses lysosomal cholesterol levels. Additionally, we identify indoxyl sulfate (IS) as a binding ligand to the permease domain, confirmed by the LYCHOS-IS complex structure. Overall, our study provides a foundation and indicates additional directions for further investigation of the essential role of LYCHOS in the mTORC1 signaling pathway.

Plant Derived Exosome-Like Nanoparticles and Their Therapeutic Applications in Glucolipid Metabolism Diseases

Plant derived exosome-like nanoparticles (PELNs) are membrane structures isolated from different plants, which encapsulate many active substances such as proteins, lipids, and nucleic acids, which exert a substantial influence on many physiological processes such as plant growth and development, self-defense, and tissue repair. Compared with synthetic nanoparticles and mammalian cell derived exosomes (MDEs), PELNs have lower toxicity and immunogenicity and possess excellent biocompatibility. The intrinsic properties of PELNs establish a robust basis for their applications in the therapeutic management of a diverse array of pathologies. It is worth mentioning that PELNs have good biological targeting, which promotes them to load and deliver drugs to specific tissues, offering a superior development pathway for the construction of a new drug delivery system (DDS). Glucose and lipid metabolism is a vital life process for the body's energy and material supply. The maintenance of homeostatic balance provides a fundamental basis for the body's ability to adjust to modifications in both its internal and external environment. Conversely, homeostatic imbalance can lead to a range of severe metabolic disorders. This work provides a comprehensive overview of the extraction and representation methods of PELNs, their transportation and storage characteristics, and their applications as therapeutic agents for direct treatment and as delivery vehicles to enhance nutrition and health. Additionally, it examines the therapeutic efficacy and practical applications of PELNs in addressing abnormalities in glucose and lipid metabolism. Finally, combined with the above contents, the paper summarizes and provides a conceptual framework for the better application of PELNs in clinical disease treatment.

Analysis of Risk Factors for Poor Prognosis Following Small Artery Occlusion or Lacunar Stroke: A Retrospective Cohort Study

Objective

To investigate the risk factors and predictive value for poor prognosis following small artery occlusion stroke (SAO) or lacunar stroke.

Methods

A retrospective cohort of 100 SAO patients who received their first intravenous thrombolysis (IVT) treatment with alteplase between March 2019 and March 2021 was collected. Based on the modified Rankin Scale (mRS) score of <3 at 90 days post-admission, patients were divided into a good prognosis group (61 cases) and a poor prognosis group (39 cases) for comparative analysis.

Results

In our retrospective cohort study of 100 SAO patients treated with IVT from March 2019 to March 2021, we found no significant differences in gender, age or BMI between the 61 patients with good prognosis and the 39 with poor prognosis, although smoking habits varied. Statistically differences were observed between the two groups in terms of time from onset to hospital admission for thrombolysis (48.59±20.14 vs 40.03±23.73 min, t=2.202, P=0.030), triglycerides (1.56±0.92 vs 1.20±0.68 mmol/L, t=2.069, P=0.041), and smoking prevalence (42.62% vs 20.51%, χ2 =5.183, P=0.023). Regression analysis indicated that shorter time from onset to hospital admission for thrombolysis (OR=0.978, 95% CI: 0.957-0.993) was a protective factor against poor prognosis post-thrombolysis in SAO patients, while a history of smoking (OR=2.881, 95% CI: 1.115-7.444) was a risk factor for poor prognosis post-thrombolysis. The area under the curve (AUC) for predicting poor prognosis post-thrombolysis in SAO patients based on time from onset to hospital admission was 0.662 (95% CI: 0.552-0.771), with a cutoff value of 36.5 min; the AUC for predicting poor prognosis based on smoking history was 0.614 (95% CI: 0.502-0.726).

Conclusion

An extended duration from onset to hospital admission for thrombolysis and smoking are identified as significant risk factors for poor prognosis following thrombolysis in SAO patients, both of which have substantial predictive value.

Development of a Novel 18F-Labeled Radioligand for Imaging Cholesterol 24-Hydroxylase with Positron Emission Tomography

Cholesterol 24-hydroxylase (CYP46A1), also known as CH24H, is a brain-specific monooxygenase responsible for the elimination of cholesterol from the central nervous system (CNS). It catalyzes the conversion of cholesterol to 24(S)-hydroxycholesterol, the primary pathway for CNS cholesterol clearance. Dysregulation of cholesterol homeostasis has been implicated in neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). This study presents the synthesis and evaluation of [18F]5 ([18F]CHL2310) as a novel radioligand for imaging CYP46A1 and cholesterol metabolism in the brain by positron emission tomography (PET). CHL2310 was identified as a potent inhibitor of CYP46A1 and subsequently labeled with fluorine-18 in a radiochemical yield of 13% and a high molar activity of 93 GBq/μmol. [18F]CHL2310 was evaluated in rats using in vitro autoradiography and PET imaging, demonstrating high brain uptake, heterogeneous brain distribution, favorable binding specificity, and suitable clearance kinetic profiles within the CNS. In all, [18F]5 ([18F]CHL2310) represents a promising tool for noninvasive quantification of cholesterol metabolism by imaging CYP46A1.

Early Changes in the Plasma Lipidome of People at Very High Cardiovascular Risk: A New Approach to Assessing the Risk of Cardiovascular Changes

Background/Objectives: Cardiovascular disease (CVD) remains the leading cause of death worldwide and requires a deeper understanding of its pathogenesis for effective prevention and treatment. Familial hypercholesterolemia (FH), characterized by high levels of LDL cholesterol, is a significant risk factor for CVD. FH background remains unexplained despite advances in genetic testing. The aim was identification early changes in the plasma lipidome of individuals at high cardiovascular risk (HCVR) using liquid chromatography coupled with mass spectrometry. Methods: The lipidomic analysis examined over 400 compounds. Twenty individuals with suspected FH, very high cardiovascular risk (VHCVR), and undetectable mutations in the LDLR, APOB, or PCSK9 genes were compared to control group in a qualitative-quantitative analysis. Results: Multivariate analyses revealed statistically significant alterations in glycerophospholipids (GC), with a notable increase in phosphatidylcholines ((O-36:0/16:0), OR (95% CI): 1.246 (1.042-1.490), p = 0.0157), phosphatidylethanolamines ((O-40:7/22:6), OR (95% CI): 1.119 (1.039-1.205), p = 0.0028), and phosphatidylglycerol ((40:8/20:4), OR (95% CI): 1.053 (1.008-1.101), p = 0.0219) only in patients with HCVR. These changes, particularly in major classes of GC, underscored their potential as biomarkers for early assessment of cardiovascular risk. Lipidomic profiling revealed associations between specific lipid species and the comorbidities of arterial hypertension, atherosclerosis, and insulin resistance, implicating their role in atherosclerotic cardiovascular disease (ASCVD). Conclusions: This study points early changes in the plasma lipidome in individuals at HCVR, underline potential biomarkers, therapeutic targets for ASCVD, and offer opportunities to improve ASCVD diagnosis, therapy, and risk management strategies through detailed personalized medical approach.

Differential responses of the intestine and liver transcriptome to high levels of plant proteins in diets for large yellow croaker (Larimichthys crocea)

Large yellow croaker is an economically important carnivorous marine aquaculture fish in China with high protein requirements. Current fish meal - based feeds face issues like high cost and resource depletion, while plant protein sources have potential but also controversies. To explore this, a 120 - day feeding trial was conducted with a standard commercial feed (CF) and a modified feed (PF) where 70% of fish meal was replaced by plant protein. Results showed no significant growth performance differences between the two groups. Transcriptome analysis identified 557 and 308 differentially expressed genes in the liver and intestine respectively. GO and KEGG enrichment analyses indicated their association with immune response, lipid metabolism, and signal transduction. Five key genes related to metabolism and immune regulation were also found. These findings underscore the potential of integrating plant protein into fish diets, which could significantly enhance sustainable practices in global aquaculture while reducing reliance on fish meal. Emphasizing this transition is crucial for fostering environmental sustainability and supporting the future of aquaculture.

Reducing LDL-Cholesterol to Very Low Levels: Sailing Between Established Benefits and Potential Risks

In view of the growing evidence supporting more marked reductions of low-density lipoprotein cholesterol (LDL-C), according to the concept of "the lower is better" and with the availability of powerful and well tolerated lipid-lowering drugs, physicians are facing today with the clinical management of patients with very low LDL-C levels. The fear of potential risks linked to extreme reductions of LDL-C down to very low levels may lead to the de-escalation of treatments with consequent paradoxical unfavorable consequences due to the exposure to a higher cardiovascular risk. The aim of this review is to point out evidence of very low LDL-C clinical impact, with a focus on potential adverse effects. Research on cholesterol homeostasis has identified complex mechanisms which guarantee cell functions even when circulating cholesterol levels are very low. The almost complete self-sufficiency of the human body in terms of cholesterol needs is confirmed by evidence derived from genetically determined models with very low LDL-C levels. Studies on the potential harm of lowering LDL-C to very low concentrations do not confirm an increased risk of cancer or neurodegenerative disease attributable to lipid-lowering treatments, whereas evidence suggests a potential benefit in these settings. A potential increased risk of hemorrhagic stroke has been reported, suggesting tight monitoring and control of blood pressure should be implemented in patients with very low LDL-C levels. With regard to statin treatment, a dose-dependent increased risk of newly diagnosed diabetes has been reported. This adverse effect has not been found with more recently approved lipid-lowering drugs.

Anti-obesity peptides from food: Production, evaluation, sources, and commercialization

The global obesity epidemic has heightened interest in natural solutions, with anti-obesity peptides emerging as promising candidates. Derived from food sources such as plants, algae, marine organisms, and products like milk and eggs, these peptides combat obesity through various mechanisms but face challenges in production and scalability. The aim of this review is to explore their sources, mechanisms, measurement, and synthesis methods, including innovative approaches such as de novo synthesis, proteomics, and bioinformatics. Its unique contribution lies in critically analyzing the current state of research while highlighting novel synthesis techniques and their practical relevance in addressing commercialization challenges, offering valuable insights for advancing anti-obesity peptide development. Diverse methods for assessing the anti-obesity properties of these peptides are discussed, encompassing both in vitro and in vivo experimental approaches, as well as emerging alternatives. The review also explores the integration of cutting-edge technologies in peptide synthesis with the potential to revolutionize scalability and cost-effectiveness. Key findings assert that despite the great potential of peptides from various food sources to fight against obesity and advances in their identification and analysis, challenges like scalability, regulatory hurdles, bioavailability issues, high production costs, and consumer appeal persist. Future research should explore the use of bioinformatics tools and advanced peptide screening technologies to identify and design peptides with enhanced efficacy and bioavailability, efficient and cost-effective extraction and purification methods, sustainable practices such as utilizing byproducts from the food industry, and the efficacy of products containing isolated anti-obesity peptides versus whole materials in clinical settings.

Gallstones in the Era of Metabolic Syndrome: Pathophysiology, Risk Prediction, and Management

Gallstone disease (GSD) and metabolic syndrome (MetS) are increasingly prevalent conditions with significant global health implications. Recent evidence highlights a strong epidemiological association between these disorders, driven by shared pathophysiological mechanisms. This review provides a comprehensive analysis of the intricate relationship between MetS and GSD, focusing on the role of insulin resistance, dyslipidemia, obesity, and gut microbiota dysbiosis in gallstone formation. An integrated pathophysiological model is proposed, linking metabolic disturbances to bile cholesterol supersaturation, gallbladder dysmotility, and chronic inflammation. The review also explores clinical implications, including risk prediction models based on metabolic parameters, early detection biomarkers, and targeted interventions such as lifestyle modifications, pharmacological therapies, and microbiome modulation. By addressing the metabolic underpinnings of GSD, this synthesis offers a foundation for developing preventive and therapeutic strategies to mitigate the burden of these interconnected conditions. Future research directions are outlined to refine mechanistic insights and improve clinical outcomes.

Biomimetic niosomal versus liposomal nanoparticle-based aspirin injection for treating stroke and myocardial infarction

In this work, we are comparing biomimetic niosomal nanoparticles (BNNs) with biomimetic liposomal nanoparticles (BLNs) and studying their drug carrier properties. A-BNNs and A-BLNs are prepared by lipid hydration method and characterized using DLS for size and zeta potential analysis, surface morphology by SEM, structural details by TEM, crystallinity and phase change by XRD, thermodynamic properties by DSC, TGA and DTGA, drug carrier properties by entrapment efficiency, drug release studies by open-end tube method and its mechanistic assessment by fitting with various models such as zero order, first order, Higuchi and Korsmeyer-Peppas models. The A-BNNs had an average size of 157.0 ± 3.58 nm and A-BLNs had an average size of 173 ± 1.24 nm. The A-BNNs had an average zeta potential of -29.0 ± 1.11 mV and A-BLNs had an average zeta potential of -46.5 ± 1.11 mV. The A-BNNs have an average entrapment efficiency of 94 ± 0.4% and A-BLNs have an average entrapment efficiency of 98 ± 0.14%. The BNNs have an average drug release of 78.12 ± 1.57% and A-BLNs have an average release of 98.41 ± 1.87% over 24 hours. Our results show that the vesicular size dependence influences the resulting nanoparticle drug carrier properties. This is a robust demonstration of the phenomena at the nanoscale that the precursor vesicular system size dependency will be reflected in bulk-engineered nanoparticle properties. These novel nanoparticles are potential candidates for development as an injection to suppress clots in stroke and myocardial infarction.

RNASET2 Deficiency Induces Hepatocellular Carcinoma Metastasis through Cholesterol-Triggered MET Activation

Metastasis remains a significant challenge in the treatment of hepatocellular carcinoma (HCC). The role of ribonuclease T2 (RNASET2) in HCC is still uncertain, although it has been reported to have contradictory effects on some cancers. Here, it is demonstrated that RNASET2 knockout leads to significant accumulation of cholesterol, which in turn promotes MET-mediated HCC metastasis. Mechanistically, the absence of RNASET2 hinders the degradation of RNA into uridine, thereby reducing the conversion to UTP. This reduction restrains glucuronate metabolism and the expression of the related enzyme UDP-glucuronosyltransferase (UGT)1A1, ultimately resulting in the accumulation of cholesterol due to decreased formation of glucuronidated-bile acids. The administration of cholesterol induces the migration and invasion of HCC cells through MET (mesenchymal-epithelial transition factor) activation. However, the deficiency of RNASET2-induced HCC metastasis can be reversed by blocking MET with shRNA or savolitinib. The study identifies RNASET2 as a key regulator that coordinates RNA, glucuronate, and cholesterol metabolism. Its deficiency drives HCC metastasis through cholesterol-triggered MET activation. These findings highlight the potential of targeting RNASET2 and MET in improving the prognosis of HCC.

The interplay of LDLR, PCSK9, and lncRNA- LASER genes expression in coronary artery disease: Implications for therapeutic interventions

BACKGROUND AND PURPOSE

Coronary artery disease (CAD) is defined as stenosis of coronary arteries due to atherosclerosis. The etiology of atherosclerosis can be attributed to a disruption in lipid metabolism, specifically cholesterol and low-density lipoprotein cholesterol (LDL-C). PCSK9 is an enzyme that controls the metabolism of LDL-C by degrading the low-density lipoprotein receptor (LDLR), which in turn affects the metabolism of LDL-C. A newly discovered Long Non-coding RNA named LASER, which affects the homeostasis of cholesterol, has been identified through the evaluation of bioinformatics. The objective of this study was to assess the levels of gene expression related to cholesterol balance, specifically LDLR, PCSK9, and LASER, in peripheral blood mononuclear cells (PBMCs) of Iranian CAD patients in comparison to controls.

EXPERIMENTAL APPROACH

This case-control study included 49 CAD patients, with 81.63 % receiving statins, compared to 40 control subjects, of whom 40 % received statins. The qRT-PCR was used to analyze the expression levels of LDLR, PCSK9, and LASER in PBMCs. Additionally, the ELISA method was employed to determine the blood concentration of PCSK9.

FINDINGS / RESULTS

CAD patients demonstrated a significant reduction in PBMC gene expression levels of LDLR (P < 0.01) and a significant rise in gene expression of PCSK9 and LASER, as well as blood concentration of PCSK9 (P < 0.05) compared to controls. The gene expression of PCSK9 showed a strong positive relationship with LDLR expression in patients (P = 0.0003). Furthermore, a strong correlation was seen between PCSK9 and LASER, as well as LASER and LDLR expression (P < 0.0001) in two groups.

CONCLUSION AND IMPLICATIONS

PCSK9 and LASER are potential therapeutic targets for atherosclerosis-related disorders, including CAD. Given that patients receiving statins were twice that of the control subjects, and the effect of statins on the LDLR, PCSK9 and LASER, further research is required to delineate the distinct effects of coronary artery disease conditions and statin usage on the expression of the aforementioned genes.

YY2-CYP51A1 signaling suppresses hepatocellular carcinoma progression by restraining de novo cholesterol biosynthesis

Lipid accumulation is a frequently observed characteristic of cancer. Lipid accumulation is closely related to tumor progression, metastasis, and drug resistance; however, the mechanism underlying lipid metabolic reprogramming in tumor cells is not fully understood. Yin yang 2 (YY2) is a C2H2‑zinc finger transcription factor that exerts tumor-suppressive effects. However, its involvement in tumor cell lipid metabolic reprogramming remains unclear. In the present study, we identified YY2 as a novel regulator of cholesterol metabolism. We showed that YY2 suppressed cholesterol accumulation in hepatocellular carcinoma (HCC) cells by downregulating the transcriptional activity of cytochrome P450 family 51 subfamily A member 1 (CYP51A1), a key enzyme in de novo cholesterol biosynthesis. Subsequently, through in vitro and in vivo experiments, we demonstrated that this downregulation is crucial for the YY2 tumor suppressive effect. Together, our findings unraveled a previously unprecedented regulation of HCC cells cholesterol metabolism, and eventually, their tumorigenic potential, through YY2 negative regulation on CYP51A1 expression. This study revealed a novel regulatory mechanism of lipid metabolic reprogramming in tumor cells and provided insights into the molecular mechanism underlying the YY2 the suppressive effect. Furthermore, our findings suggest a potential antitumor therapeutic strategy targeting cholesterol metabolic reprogramming using YY2.

M6A methyltransferase METTL3 promotes glucose metabolism hub gene expression and induces metabolic dysfunction-associated steatotic liver disease (MASLD)

BACKGROUND

N6-methyladenosine (m6A) RNA modification plays a crucial role in various biological events and is implicated in various metabolic-related diseases. However, its role in MASLD remains unclear. This study aims to investigate the impact of METTL3 on MASLD through multi-omics analysis, with a focus on exploring its potential mechanisms of action.

METHODS

An MASLD mouse model was established by feeding C57BL/6J mice a high-fat diet for 12 weeks. A METTL3 stable overexpression AML12 cell model was also constructed via lentiviral transfection. Subsequent transcriptomic and proteomic analyses, as well as integrated analysis between different omics datasets, were conducted.

RESULTS

METTL3 expression was significantly increased in the MASLD mouse model. Through our transcriptomic and proteomic analyses, we identified 848 genes with significant inconsistencies between the transcriptomic and proteomic datasets. GO/ KEGG enrichment analyses identified terms that may be involved in post-transcriptional modifications, particularly METTL3-mediated m6A modification. Subsequently, through integrated proteomic analysis of the METTL3-overexpressed AML12 cell model and the MASLD mouse model, we selected the top 20 co-upregulated and co-downregulated GO/ KEGG terms as the main biological processes influenced by METTL3 during MASLD. By intersecting with pathways obtained from previous integrated analyses, we identified GO/ KEGG terms affected by METTL3-induced m6A modification. Protein-protein interaction analysis of proteins involved in these pathways highlighted GAPDH and TPI1 as two key hub genes.

CONCLUSIONS

During MASLD, METTL3 regulates the glycolytic pathway through m6A modification, influencing the occurrence and development of the disease via the key hub genes GAPDH and TPI1. These findings expand our understanding of MASLD and provide strong evidence for potential therapeutic targets and drug development.

Μetabolic dysfunction-associated steatotic liver disease: a condition of heterogeneous metabolic risk factors, mechanisms and comorbidities requiring holistic treatment

Μetabolic dysfunction-associated steatotic liver disease (MASLD) comprises a heterogeneous condition in the presence of steatotic liver. There can be a hierarchy of metabolic risk factors contributing to the severity of metabolic dysfunction and, thereby, the associated risk of both liver and extrahepatic outcomes, but the precise ranking and combination of metabolic syndrome (MetS) traits that convey the highest risk of major adverse liver outcomes and extrahepatic disease complications remains uncertain. Insulin resistance, low-grade inflammation, atherogenic dyslipidaemia and hypertension are key to the mechanisms of liver and extrahepatic complications. The liver is pivotal in MetS progression as it regulates lipoprotein metabolism and secretes substances that affect insulin sensitivity and inflammation. MASLD affects the kidneys, heart and the vascular system, contributing to hypertension and oxidative stress. To address the global health burden of MASLD, intensified by obesity and type 2 diabetes mellitus epidemics, a holistic, multidisciplinary approach is essential. This approach should focus on both liver disease management and cardiometabolic risk factors. This Review examines the link between metabolic dysfunction and liver dysfunction and extrahepatic disease outcomes, the diverse mechanisms in MASLD due to metabolic dysfunction, and a comprehensive, personalized management model for patients with MASLD.

Identification of tacrolimus-related genes in familial combined hyperlipidemia and development of a diagnostic model using bioinformatics analysis

Background

Clinical observations have revealed that patients undergoing organ transplantation administered tacrolimus often experience abnormal lipid metabolism with serious consequences. Thus, the intricate interplay between tacrolimus and lipid metabolism must be addressed to develop targeted therapeutic interventions. Our ongoing research aims to develop precision medicine approaches that not only alleviate the immediate repercussions for organ transplant patients but also enhance their long-term outcomes. To this end, we investigated the potential genes associated with tacrolimus metabolism in familial combined hyperlipidemia (FCHL) to identify relevant biomarkers of FCHL, develop predictive diagnostic models for hyperlipidemia, and reveal potential therapeutic targets for FCHL.

Methods

Dataset GSE1010 containing information on patients diagnosed with FCHL was obtained from the Gene Expression Omnibus (GEO), and an ensemble of tacrolimus-related genes (TRGs) was retrieved from the GeneCards, STITCH, and Molecular Signatures Database databases. A thorough weighted gene co-expression network analysis was conducted, including a differential expression analysis of the GSE1010 and TRG datasets, to identify intricate patterns of gene co-expression and provide insights on the underlying molecular dynamics within the datasets. Key genes were screened, diagnostic models were constructed, and all genes associated with logFC values were assessed using gene set variation and enrichment analyses. Upregulated genes were identified by a positive logFC (>0) and P < 0.05, while downregulated genes were characterized by a negative logFC (<0) and P < 0.05. These criteria facilitated a more nuanced categorization of gene expression changes within the analyzed datasets. Given tacrolimus's immunosuppressive impact, the gene expression matrix data obtained from dataset GSE1010 was submitted to CIBERSORT to assess immune cell infiltration outcomes. Finally, we examined the regulatory network of screened key genes that interact with RNA-binding proteins, potential drugs, small-molecule compounds, and transcription factors.

Results

We screened 14 statistically significant key genes, built a reliable risk model, and grouped the dataset into categories at high and low risk for hyperlipidemia development. FCHL was linked to memory B and immature B immune cells. The gene set variation analysis revealed two pathways associated with cholesterol homeostasis and the complement system that were closely associated with the potential functions of FCHL and tacrolimus-related differentially expressed genes.

Conclusions

Our research offers a better understanding of FCHL and the TRGs involved in lipid metabolism. Additionally, it provides research directions for identifying potential targets for clinical therapies.

The low-density lipoprotein receptor: Emerging post-transcriptional regulatory mechanisms

Cholesterol is a vital component of cellular membranes and is an essential molecule in mammalian physiology. Yet dysregulation of hepatic cholesterol metabolism and an increase in plasma cholesterol is linked to development of atherosclerotic cardiovascular disease. Maintaining tight regulation of cholesterol homeostasis is therefore essential, elegantly highlighted by the control of hepatic low-density lipoprotein receptor (LDLR) abundance and associated lipoprotein clearance. The LDLR was discovered in the 1970's in the seminal work of Brown and Goldstein. This was followed by the development of statins, which promote hepatic clearance of LDL via the LDLR pathway. The discovery two decades ago of Proprotein Convertase Subtilisin-Kexin Type 9 (PCSK9), a secreted protein that binds to the LDLR ectodomain and promotes its degradation, and the clinical development of PCSK9 inhibitors has ushered an effort to uncover additional mechanisms that govern the function and abundance of the LDLR. In recent years this has led to the identification of novel post-transcriptional and post-translational mechanisms that govern the LDLR. This review focuses on these emerging regulatory mechanisms and specifically discusses: (1) Regulation of the LDLR mRNA by RNA-binding proteins and microRNAs, (2) Ubiquitin-dependent degradation of the LDLR protein by the E3 ubiquitin ligases inducible degrader of the LDLR (IDOL) and GOLIATH (RNF130), (3) Control of the LDLR pathway by the asialoglycoprotein receptor 1 (ASGR1), and (4) The role of LDLR ectodomain shedding mediated by membrane-type 1 matrix metalloprotease (MT1-MMP), Bone morphogenetic protein 1 (BMP1), and γ-secretase. Understanding the contribution of these emerging mechanisms to regulation of the LDLR is important for the development of novel LDLR-focused lipid-lowering strategies.

Enhancement of Intracellular Cholesterol Efflux in Chondrocytes Leading to Alleviation of Osteoarthritis Progression

OBJECTIVE

Osteoarthritis (OA) is the most common degenerative disease worldwide, with no practical means of prevention and limited treatment options. Recently, our group unveiled a novel mechanism contributing to OA pathogenesis in association with abnormal cholesterol metabolism in chondrocytes. In this study, we aimed to establish a clinical link between lipid profiles and OA in humans, assess the effectiveness of cholesterol-lowering drugs in suppressing OA development in mice, and uncover the cholesterol-lowering mechanisms that effectively impede OA progression.

METHODS

Five clinically approved cholesterol-lowering drugs (fenofibrate, atorvastatin, ezetimibe, niacin, and lomitapide) were injected into the knee joints or administered with diet to mice with OA who underwent destabilization of the medial meniscus induction and were fed a 2% high-cholesterol diet. Gene expression linked to cholesterol metabolism was determined using microarray analysis. Furthermore, the in vivo functions of these genes were explored through intra-articular injection of either its inhibitor or adenovirus.

RESULTS

Logistic regression analysis confirmed a close relationship between the diagnostic criteria of hyperlipidemia based on serum lipid levels and OA incidence. Among the cholesterol-lowering drugs examined, fenofibrate exerted the most significant protective effect against cartilage destruction, which was attributed to elevated levels of high-density lipoprotein cholesterol that are crucial for cholesterol efflux. Notably, cholesterol efflux was suppressed during OA progression via down-regulation of apolipoprotein A1-binding protein (AIBP) expression. Overexpression of AIBP effectively inhibits OA progression.

CONCLUSION

Our results suggest that restoration of cholesterol homeostasis to a normal state through administration of fenofibrate or AIBP overexpression, both of which induce cholesterol efflux, offers an effective therapeutic option for patients with OA.

Plasma from type 1 diabetes patients promotes pro-atherogenic cholesterol transport in human macrophages

Hyperglycemia, one of the major risk factors for atherosclerosis, leads to the accumulation of advanced glycation end products (AGEs), contributing to cardiovascular complications. Such accumulation may accelerate the progression of vascular disease in patients with diabetes. Reverse cholesterol transport (RCT) protein, ATP-binding membrane cassette transporters A1 and G1 (ABCA1 and ABCG1) and cholesterol 27-hydroxylase facilitate cholesterol removal from macrophages. AGE inhibits RCT by reducing the expression of ABCA1 and ABCG1. This study aimed to evaluate whether plasma from poorly controlled adolescents with type 1 diabetes (T1D) disrupts cholesterol homeostasis in human monocytes/macrophages. Twenty healthy controls (HCs) and 20 patients with type 1 diabetes mellitus (T1DM), 10-19 years old, were enrolled. Naïve THP-1 macrophages were exposed to plasma from each HC and patient with T1D. Following incubation, mRNA for cholesterol efflux (ABCA1, ABCG1, and 27-hydroxylase) and cholesterol uptake (CD36, ScR-A1, lectin oxidized low-density lipoprotein (LOX)-1, and CXCL16) were isolated. Foam cell formation was quantified to confirm the pro-atherogenic effects of T1D plasma on macrophages. Results showed that T1D plasma had an elevated level of N-(carboxymethyl)-lysine-modified proteins and upregulated CXCL16 and, to a lesser degree, ScR-A1. This change in gene expression in the presence of T1D plasma is associated with increased lipid accumulation and foam cell formation by THP-1 macrophages. In our study, these cells' uptake of an AGE product occurred mainly through the SR-A1 and CXCL16 receptors, leading to increased intracellular oxidized low-density lipoprotein. We conclude that AGEs may contribute to accelerated atherosclerosis in diabetes through effects on both forward and reverse cholesterol movement.

Immunomodulatory effect of efferocytosis at the maternal-fetal interface

Efferocytosis is a mechanism by which phagocytes efficiently clear apoptotic cells, averting their secondary necrosis and the subsequent release of potentially immunogenic or cytotoxic substances that can trigger strong immune and inflammatory responses. During efferocytosis, the metabolic pathways of phagocytes are transformed, which, along with the catabolism of apoptotic cargo, can affect their function and inflammatory state. Extensive apoptosis occurs during placental development, and some studies reported the immunomodulatory effects of efferocytosis at the maternal-fetal interface. The dysregulation of efferocytosis is strongly linked to pregnancy complications such as preeclampsia and recurrent spontaneous abortion. In this review, we discuss the mechanisms of efferocytosis and its relationships with metabolism and inflammation. We also highlight the roles of professional and non-professional phagocytes in efferocytosis at the maternal-fetal interface and their impact on pregnancy outcomes and explore relevant regulatory factors. These insights are expected to guide future basic research and clinical strategies for identifying efferocytosis-related molecules as potential predictors or therapeutic targets in obstetric diseases.

Impaired Molecular Mechanisms Contributing to Chronic Pain in Patients with Hidradenitis Suppurativa: Exploring Potential Biomarkers and Therapeutic Targets

Hidradenitis suppurativa (HS) is a chronic skin condition that primarily affects areas with dense hair follicles and apocrine sweat glands, such as the underarms, groin, buttocks, and lower breasts. Intense pain and discomfort in HS have been commonly noted, primarily due to the lesions' effects on nearby tissues. Pain is a factor that can influence DNA methylation patterns, though its exact role in HS is not fully understood. We aim to identify molecular markers of chronic pain in HS patients. We performed DNA methylome of peripheral blood DNA derived from a group of 24 patients with HS and 24 healthy controls, using Illumina methylation array chips. We identified 253 significantly differentially methylated CpG sites across 253 distinct genes regulating pain sensitization in HS, including 224 hypomethylated and 29 hypermethylated sites. Several genes with pleiotropic roles include transporters (ABCC2, SLC39A8, SLC39A9), wound healing (MIR132, FGF2, PDGFC), ion channel regulators (CACNA1C, SCN1A), oxidative stress mediators (SCN8A, DRD2, DNMT1), cytochromes (CYP19A, CYP1A2), cytokines (TGFB1, IL4), telomere regulators (CSNK1D, SMAD3, MTA1), circadian rhythm (IL1R2, ABCG1, RORA), ultradian rhythms (PHACTR1, TSC2, ULK1), hormonal regulation (PPARA, NR3C1, ESR2), and the serotonin system (HTR1D, HTR1E, HTR3C, HTR4, TPH2). They also play roles in glucose metabolism (POMC, IRS1, GNAS) and obesity (DRD2, FAAH, MMP2). Gene ontology and pathway enrichment analysis identified 43 pathways, including calcium signaling, cocaine addiction, and nicotine addiction. This study identified multiple differentially methylated genes involved in chronic pain in HS, which may serve as biomarkers and therapeutic targets. Understanding their epigenetic regulation is crucial for personalized pain management and could enhance the identification of high-risk patients, leading to better preventative therapies and improved maternal and neonatal outcomes.

Fc-binding nanodisc restores antiviral efficacy of antibodies with reduced neutralizing effects against evolving SARS-CoV-2 variants

Passive antibody therapies, typically administered via parenteral routes, have played a crucial role in the initial response to the COVID-19 pandemic. However, the ongoing evolution of SARS-CoV-2 has revealed significant limitations of this approach, primarily due to mutational escape and the inadequate delivery of antibodies to the upper respiratory tract. To overcome these challenges, we propose a novel prophylactic strategy involving the intranasal delivery of an antibody in combination with an Fc-binding nanodisc. This nanodisc, engineered to specifically bind to the Fc regions of IgG antibodies, served two key functions: extending the antibody's half-life in the larynx and trachea, and enhancing its neutralization efficacy. Notably, Sotrovimab, an FDA-approved monoclonal antibody that has experienced a significant decline in neutralizing potency due to viral evolution, exhibited robust antiviral activity when complexed with the nanodisc against all tested Omicron variants. Furthermore, the Fc-binding nanodisc significantly boosted the antiviral efficacy of the soluble angiotensin-converting enzyme 2 (sACE2) Fc fusion protein, which possesses broad but modest antiviral activity. In ACE2 transgenic mice, the Fc-binding nanodisc protected better than sACE2-Fc alone with two more log reduction in lung viral titer. Therefore, the intranasal Fc-binding nanodisc offers a promising and powerful approach to counteract the diminished antiviral activity of neutralizing antibodies caused by mutational escape, effectively restoring antiviral efficacy against various evolving SARS-CoV-2 variants.

The ultimate microbial composition for correcting Th17/Treg cell imbalance and lipid metabolism disorders in osteoporosis

Osteoporosis is a systemic bone disease characterised by decreased bone mass and a deteriorated bone microstructure, leading to increased bone fragility and fracture risk. Disorders of the intestinal microbiota may be key inducers of osteoporosis. Furthermore, such disorders may contribute to osteoporosis by influencing immune function and lipid metabolism. Therefore, in this review, we aimed to summarise the molecular mechanisms through which the intestinal microbiota affect the onset and development of osteoporosis by regulating Th17/Treg imbalance and lipid metabolism disorders. We also discussed the regulatory mechanisms underlying the effect of intestinal microbiota-related modulators on Th17/Treg imbalance and lipid metabolism disorders in osteoporosis, to explore new molecular targets for its treatment and provide a theoretical basis for clinical management.

Free Cholesterol-Induced Liver Injury in Non-Alcoholic Fatty Liver Disease: Mechanisms and a Therapeutic Intervention Using Dihydrotanshinone I

Build-up of free cholesterol (FC) substantially contributes to the development and severity of non-alcoholic fatty liver disease (NAFLD). Here, we investigate the specific mechanism by which FC induces liver injury in NAFLD and propose a novel therapeutic approach using dihydrotanshinone I (DhT). Rather than cholesterol ester (CE), we observed elevated levels of total cholesterol, FC, and alanine transaminase (ALT) in NAFLD patients and high-cholesterol diet-induced NAFLD mice compared to those in healthy controls. The FC level demonstrated a positive correlation with the ALT level in both patients and mice. Mechanistic studies revealed that FC elevated reactive oxygen species level, impaired the function of lysosomes, and disrupted lipophagy process, consequently inducing cell apoptosis. We then found that DhT protected mice on an HCD diet, independent of gut microbiota. DhT functioned as a potent ligand for peroxisome proliferator-activated receptor α (PPARα), stimulating its transcriptional function and enhancing catalase expression to lower reactive oxygen species (ROS) level. Notably, the protective effect of DhT was nullified in mice with hepatic PPARα knockdown. Thus, these findings are the first to report the detrimental role of FC in NAFLD, which could lead to the development of new treatment strategies for NAFLD by leveraging the therapeutic potential of DhT and PPARα pathway.

Biological Functions and Clinical Significance of the ABCG1 Transporter

ATP-binding cassette (ABC) transporters are a large family of proteins that transport various substances across cell membranes using energy from ATP hydrolysis. ATP-binding cassette sub-family G member 1 (ABCG1) is a member of the ABCG subfamily of transporters and performs many important functions, such as the export of cholesterol and some other lipids across the membranes of various cells. Cholesterol transport is the mechanism that links metabolism and the innate immune system. Due to its lipid transport function, ABCG1 may contribute to the prevention of atherosclerosis and is involved in the functioning of the lung, pancreas, and other organs and systems. However, the full clinical significance of ABCG1 is still unknown and is a promising area for future research.

Maternal high-fat diet orchestrates offspring hepatic cholesterol metabolism via MEF2A hypermethylation-mediated CYP7A1 suppression

BACKGROUND

Maternal overnutrition, prevalent among women of childbearing age, significantly impacts offspring health throughout their lifetime. While DNA methylation of metabolic-related genes mediates the transmission of detrimental effects from maternal high-fat diet (HFD), its role in programming hepatic cholesterol metabolism in offspring, particularly during weaning, remains elusive.

METHODS

Female C57BL/6 J mice were administered a HFD or control diet, before and during, gestation and lactation. Hepatic cholesterol metabolism genes in the liver of offspring were evaluated in terms of their expression. The potential regulator of cholesterol metabolism in the offspring's liver was identified, and the function of the targeted transcription factor was evaluated through in vitro experiments. The methylation level of the target transcription factor was assessed using the MassARRAY EpiTYPER platform. To determine whether transcription factor expression is influenced by DNA methylation, in vitro experiments were performed using 5-azacitidine and Lucia luciferase activity assays.

RESULTS

Here, we demonstrate that maternal HFD results in higher body weight and hypercholesterolemia in the offspring as early as weaning age. Maternal HFD feeding exacerbates hepatic cholesterol accumulation in offspring primarily by inhibiting cholesterol elimination to bile acids, with a significant decrease of hepatic cholesterol 7α-hydroxylase (CYP7A1). RNA-seq analysis identified myocyte enhancer factor 2A (MEF2A) as a key transcription factor in the offspring liver, which was significantly downregulated in offspring of HFD-fed dams. MEF2A knockdown led to CYP7A1 downregulation and lipid accumulation in HepG2 cells, while MEF2A overexpression reversed this effect. Dual luciferase reporter assays confirmed direct modulation of CYP7A1 transcription by MEF2A. Furthermore, the reduced MEF2A expression was attributed to DNA hypermethylation in the Mef2a promoter region. This epigenetic modification manifested as early as the fetal stage.

CONCLUSIONS

This study provides novel insights into how maternal HFD orchestrates hepatic cholesterol metabolism via MEF2A hypermethylation-mediated CYP7A1 suppression in offspring at weaning.

Acetyl-L-carnitine ameliorates atherosclerosis in LDLR-/- mice by modulating cholesterol metabolism through SREBP2-dependent cholesterol biosynthesis

Background

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of mortality globally. Hypercholesterolemia accelerates atherosclerotic development and is an independent modifiable risk factor for ASCVD. Reducing cholesterol levels is effective in preventing ASCVD. Acetyl-L-carnitine (ALC) is an endogenous molecule that plays a primary role in energy metabolism; however, its effect on cholesterol metabolism remains unclear.

Methods

We collected plasma samples and clinical data from 494 individuals with hyperlipidemia. Targeted metabolomics were used to measure plasma ALC levels and explore the association of ALC with clinical cholesterol levels. Additionally, we explored the effects of ALC in cholesterol levels and cholesterol metabolism in a murine hypercholesterolemia model. An LDLR-/- mouse-based atherosclerotic model was established to investigate the roles of ALC on atherosclerotic progression.

Results

Plasma ALC concentrations were significantly negatively correlated with plasma total cholesterol (TC) levels (r = -0.43, p < 0.0001) and low-density lipoprotein cholesterol (LDL-C; r = -0.53, p < 0.0001). Incorporating ALC into the diet significantly reduced plasma TC and LDL-C levels, downregulated genes involved in cholesterol synthesis, such as sterol regulatory element-binding protein 2 (SREBP2) and 3-hydroxy-3-methyl-glutaryl-CoA reductase, and upregulated low-density lipoprotein receptor expression. ALC supplementation substantially lowered plasma TC levels and inhibited atherosclerosis in LDLR-/- mice.

Conclusion

ALC reduced atherosclerotic plaque formation by lowering plasma cholesterol levels via suppression of SREBP2-mediated cholesterol synthesis, thus suggesting that ALC is a potential therapeutic target for ASCVD.

Ultra-small phospholipid nanoparticles in the treatment of combined hyperlipidemia: a randomized placebo-controlled clinical trial

Background and purpose

Combined hyperlipidemia is associated with an increased risk of cardiovascular events. This clinical trial investigated phospholipovit (essential phospholipids, Institute of Biomedical Chemistry, Moscow, Russia), an ultra-small phospholipid nanoparticle (micelles), targeted to phospholipids of HDL in lowering non-HDL-cholesterol (non-HDL-C) and triglycerides (TG) levels in patients with combined hyperlipidemia and moderate cardiovascular risk.

Experimental approach

A randomized, double-blinded, placebo-controlled phase II trial was conducted on 100 patients. Phospholipovit or placebo was randomly administered orally (500 mg) 2 times a day for 12 weeks. The primary endpoint was the percent change of non-HDL-C from baseline to 12 weeks of exposure.

Findings/Results

Treatment with phospholipovit resulted in a mean non-HDL-C reduction of 13.2% versus 4.3% compared with placebo. The absolute decrease in non-HDL-C was -23.2 (-48.7 - 7.0) mg/dL versus -7.3 (-17.0 - 12.0) mg/dL, significantly. The therapeutic target of non-HDL-C less than 130 mg/dL (3.4 mmol) was achieved in 15 of 39 patients (38.5%) in the phospholipovit group versus 2 of 41 patients (4.9%) in the placebo group OR 11.8 (2.4 - 116). Significant reduction in TG, apolipoprotein B, total cholesterol, and very low-density lipoprotein cholesterol levels was also observed. There were no changes in the liver and kidney functions, vital signs, or electrocardiography. There were no serious adverse events.

Conclusion and implications

Phospholipovit significantly reduced non-HDL-C, TG, and atherogenic lipoproteins in patients with combined hyperlipidemia and moderate cardiovascular risk. It can be used as an add-on therapy to statins.