PPAR-alpha and PPAR-gamma activators induce cholesterol removal from human macrophage foam cells through stimulation of the ABCA1 pathway

Nonlipogenic ABCA1 Inducers (NLAI) for Alzheimer's Disease Validated in a Mouse Model Expressing Human APOE3/APOE4

Therapeutics enhancing apolipoprotein (APOE) positive function are a priority, because APOE4 is the major genetic risk factor for Alzheimer's disease (AD). The function of APOE, the key constituent of lipoprotein particles that transport cholesterol and lipids in the brain, is dependent on lipidation by ABCA1, a cell-membrane cholesterol transporter. ABCA1 transcription is regulated by liver X receptors (LXR): agonists have been shown to increase ABCA1, often accompanied by unwanted lipogenesis and elevated triglycerides (TG). Therefore, nonlipogenic ABCA1-inducers (NLAI) are needed. Two rounds of optimization of an HTS hit, derived from a phenotypic screen, gave lead compound 39 that was validated and tested in E3/4FAD mice that express human APOE3/4 and five mutant APP and PSEN1 human transgenes. Treatment with 39 increased ABCA1 expression, enhanced APOE lipidation, and reversed multiple AD phenotypes, without increasing TG. This NLAI/LXR-agonist study is the first in a human APOE-expressing model with hallmark amyloid-β pathology.

Myelinated peripheral axons are more vulnerable to mechanical trauma in a model of enlarged axonal diameters

The velocity of axonal impulse propagation is facilitated by myelination and axonal diameters. Both parameters are frequently impaired in peripheral nerve disorders, but it is not known if the diameters of myelinated axons affect the liability to injury or the efficiency of functional recovery. Mice lacking the adaxonal myelin protein chemokine-like factor-like MARVEL-transmembrane domain-containing family member-6 (CMTM6) specifically from Schwann cells (SCs) display appropriate myelination but increased diameters of peripheral axons. Here we subjected Cmtm6-cKo mice as a model of enlarged axonal diameters to a mild sciatic nerve compression injury that causes temporarily reduced axonal diameters but otherwise comparatively moderate pathology of the axon/myelin-unit. Notably, both of these pathological features were worsened in Cmtm6-cKo compared to genotype-control mice early post-injury. The increase of axonal diameters caused by CMTM6-deficiency thus does not override their injury-dependent decrease. Accordingly, we did not detect signs of improved regeneration or functional recovery after nerve compression in Cmtm6-cKo mice; depleting CMTM6 in SCs is thus not a promising strategy toward enhanced recovery after nerve injury. Conversely, the exacerbated axonal damage in Cmtm6-cKo nerves early post-injury coincided with both enhanced immune response including foamy macrophages and SCs and transiently reduced grip strength. Our observations support the concept that larger peripheral axons are particularly susceptible toward mechanical trauma.

Macrophage polarization as a novel endpoint for assessing combined risk of phthalate esters

Combined exposure to phthalate esters (PAEs) has garnered increasing attention due to potential synergistic effects on human health. This study aimed to develop an in vitro model using human macrophages to evaluate the combined toxicity of PAEs and explore the underlying mechanisms. A high-throughput screening system was engineered by expressing a PPRE-eGFP reporter in THP-1 monocytes to monitor macrophage polarization upon PAEs exposure. Individual PAEs exhibited varied inhibitory effects on M2 macrophage polarization, with mono(2-ethylhexyl) phthalate (MEHP) being the most potent. Isobologram analysis revealed additive interactions when MEHP was combined with other PAEs, resulting in more pronounced suppression of M2 markers compared to individual compounds. Mechanistic studies suggested PAEs may exert effects by modulating PPARγ activity to inhibit M2 polarization. Notably, an equimolar mixture of six PAEs showed additive inhibition of M2 markers. In vivo experiments corroborated the combined hepatotoxic effects, with mice exposed to a PAEs mixture exhibiting reduced liver weight, dyslipidemia, and decreased hepatic M2 macrophages compared to DEHP alone. Transcriptome analysis highlighted disruptions in PPAR signaling, and distinct pathway alterations on cholesterol metabolism in the mixture group. Collectively, these findings underscore the importance of evaluating mixture effects and provide a novel approach for hazard assessment of combined PAEs exposure with implications for environmental health risk assessment.

miR-223 accelerates lipid droplets clearance in microglia following spinal cord injury by upregulating ABCA1

BACKGROUND

Spinal cord injury (SCI) is characterized by extensive demyelination and inflammatory responses. Facilitating the clearance of lipid droplets (LDs) within microglia contributes to creating a microenvironment that favors neural recovery and provides essential materials for subsequent remyelination. Therefore, investigating MicroRNAs (miRNAs) that regulate lipid homeostasis after SCI and elucidating their potential mechanisms in promoting LDs clearance in microglia have become focal points of SCI research.

METHODS

We established a subacute C5 hemicontusion SCI model in mice and performed transcriptomic sequencing on the injury epicenter to identify differentially expressed genes and associated pathways. Confocal imaging was employed to observe LDs accumulation. Multi-omics analyses were conducted to identify differentially expressed mRNA and miRNA post-SCI. Pathway enrichment analysis and protein-protein interaction network construction were performed using bioinformatics methods, revealing miR-223-Abca1 as a crucial miRNA-mRNA pair in lipid metabolism regulation. BV2 microglia cell lines overexpressing miR-223 were engineered, and immunofluorescence staining, western blot, and other techniques were employed to assess LDs accumulation, relevant targets, and inflammatory factor expression, confirming its role in regulating lipid homeostasis in microglia.

RESULTS

Histopathological results of our hemicontusion SCI model confirmed LDs aggregation at the injury epicenter, predominantly within microglia. Our transcriptomic analysis during the subacute phase of SCI in mice implicated ATP-binding cassette transporter A1 (Abca1) as a pivotal gene in lipid homeostasis, cholesterol efflux and microglial activation. Integrative mRNA-miRNA multi-omics analysis highlighted the crucial role of miR-223 in the neuroinflammation process following SCI, potentially through the regulation of lipid metabolism via Abca1. In vitro experiments using BV2 cells overexpressing miR-223 demonstrated that elevated levels of miR-223 enhance ABCA1 expression in myelin debris and LPS-induced BV2 cells. This promotes myelin debris degradation and LDs clearance, and induces a shift toward an anti-inflammatory M2 phenotype.

CONCLUSIONS

In summary, our study unveils the critical regulatory role of miR-223 in lipid homeostasis following SCI. The mechanism by which this occurs involves the upregulation of ABCA1 expression, which facilitates LDs clearance and myelin debris degradation, consequently alleviating the lipid burden, and inhibiting inflammatory polarization of microglia. These findings suggest that strategies to enhance miR-223 expression and target ABCA1, thereby augmenting LDs clearance, may emerge as appealing new clinical targets for SCI treatment.

Safety Implications of Modulating Nuclear Receptors: A Comprehensive Analysis from Non-Clinical and Clinical Perspectives

The unintended modulation of nuclear receptor (NR) activity by drugs can lead to toxicities amongst the endocrine, gastrointestinal, hepatic cardiovascular, and central nervous systems. While secondary pharmacology screening assays include NRs, safety risks due to unintended interactions of small molecule drugs with NRs remain poorly understood. To identify potential nonclinical and clinical safety effects resulting from functional interactions with 44 of the 48 human-expressed NRs, we conducted a systematic narrative review of the scientific literature, tissue expression data, and used curated databases (OFF-X™) (Off-X, Clarivate) to organize reported toxicities linked to the functional modulation of NRs in a tabular and machine-readable format. The top five NRs associated with the highest number of safety alerts from peer-reviewed journals, regulatory agency communications, congresses/conferences, clinical trial registries, and company communications were the Glucocorticoid Receptor (GR, 18,328), Androgen Receptor (AR, 18,219), Estrogen Receptor (ER, 12,028), Retinoic acid receptors (RAR, 10,450), and Pregnane X receptor (PXR, 8044). Toxicities associated with NR modulation include hepatotoxicity, cardiotoxicity, endocrine disruption, carcinogenicity, metabolic disorders, and neurotoxicity. These toxicities often arise from the dysregulation of receptors like Peroxisome proliferator-activated receptors (PPARα, PPARγ), the ER, PXR, AR, and GR. This dysregulation leads to various health issues, including liver enlargement, hepatocellular carcinoma, heart-related problems, hormonal imbalances, tumor growth, metabolic syndromes, and brain function impairment. Gene expression analysis using heatmaps for human and rat tissues complemented the functional modulation of NRs associated with the reported toxicities. Interestingly, certain NRs showed ubiquitous expression in tissues not previously linked to toxicities, suggesting the potential utilization of organ-specific NR interactions for therapeutic purposes.

Effects of different natural products in patients with non-alcoholic fatty liver disease-A network meta-analysis of randomized controlled trials

Due to a scarcity of appropriate therapeutic approaches capable of ameliorating or eliminating non-alcoholic fatty liver disease (NAFLD), many researchers have come to focus on natural products based on traditional medicine that can be utilized to successfully treat NAFLD. In this study, we aimed to evaluate the effects exerted by seven natural products (curcumin, silymarin, resveratrol, artichoke leaf extract, berberine, catechins, and naringenin) on patients with NAFLD. For this purpose, PubMed, Embase, Cochrane Library, and Web of Science, were searched for randomized controlled trials (RCTs) exclusively. The selected studies were evaluated for methodological quality via the Cochrane bias risk assessment tool, and data analysis software was used to analyze the data accordingly. The RCTs from the earliest available date until September 2022 were collected. This process resulted in 37 RCTs with a total sample size of 2509 patients being included. The results of the network meta-analysis showed that artichoke leaf extract confers a relative advantage in reducing the aspartate aminotransferase (AST) levels (SUCRA: 99.1%), alanine aminotransferase (ALT) levels (SUCRA: 88.2%) and low-density lipoprotein cholesterol (LDL-C) levels (SUCRA: 88.9%). Naringenin conferred an advantage in reducing triglyceride (TG) levels (SUCRA: 97.3%), total cholesterol (TC) levels (SUCRA: 73.9%), and improving high-density lipoprotein cholesterol (HDL-C) levels (SUCRA: 74.9%). High-density catechins significantly reduced body mass index (BMI) levels (SUCRA: 98.5%) compared with the placebo. The Ranking Plot of the Network indicated that artichoke leaf extract and naringenin performed better than the other natural products in facilitating patient recovery. Therefore, we propose that artichoke leaf extract and naringenin may exert a better therapeutic effect on NAFLD. This study may help guide clinicians and lead to further detailed studies.

Enhancing of cerebral Abeta clearance by modulation of ABC transporter expression: a review of experimental approaches

Clearance of amyloid-beta (Aβ) from the brain is impaired in both early-onset and late-onset Alzheimer's disease (AD). Mechanisms for clearing cerebral Aβ include proteolytic degradation, antibody-mediated clearance, blood brain barrier and blood cerebrospinal fluid barrier efflux, glymphatic drainage, and perivascular drainage. ATP-binding cassette (ABC) transporters are membrane efflux pumps driven by ATP hydrolysis. Their functions include maintenance of brain homeostasis by removing toxic peptides and compounds, and transport of bioactive molecules including cholesterol. Some ABC transporters contribute to lowering of cerebral Aβ. Mechanisms suggested for ABC transporter-mediated lowering of brain Aβ, in addition to exporting of Aβ across the blood brain and blood cerebrospinal fluid barriers, include apolipoprotein E lipidation, microglial activation, decreased amyloidogenic processing of amyloid precursor protein, and restricting the entrance of Aβ into the brain. The ABC transporter superfamily in humans includes 49 proteins, eight of which have been suggested to reduce cerebral Aβ levels. This review discusses experimental approaches for increasing the expression of these ABC transporters, clinical applications of these approaches, changes in the expression and/or activity of these transporters in AD and transgenic mouse models of AD, and findings in the few clinical trials which have examined the effects of these approaches in patients with AD or mild cognitive impairment. The possibility that therapeutic upregulation of ABC transporters which promote clearance of cerebral Aβ may slow the clinical progression of AD merits further consideration.

Antagonism of let-7c reduces atherosclerosis and macrophage lipid accumulation by promoting PGC-1α/LXRα/ABCA1/G1 pathway

Changes in circulating let-7c were significantly associated with the alter in lipid profile, but its role in intracellular lipid metabolism remains unknown. This work was conducted to explore the effects of let-7c on the lipid accumulation in macrophages and uncover the underlying mechanism. Our results showed that let-7c inhibition relieved atherosclerosis progression in apoE-/- mice. In ox-LDL-treatment macrophages, let-7c knockdown suppressed lipid accumulation but does no affect cholesterol intake. Consistent with this, overexpression of let-7c promoted lipid accumulation by reducing the expression of LXRα and ABCA1/G1. Mechanistically, let-7c targeted PGC-1α to repress the expression of LXRα and ABCA1/G1, thereby regulating cholesterol homeostasis in macrophages. Taken together, these findings suggest that antagonism of let-7c reduces atherosclerosis and macrophage lipid accumulation through the PGC-1α/LXRα/ABCA1/G1 axis.

MicroRNA-144-3p Inhibits Host Lipid Catabolism and Autophagy by Targeting PPARα and ABCA1 During Mycobacterium Tuberculosis Infection

MicroRNA-mediated metabolic reprogramming recently has been identified as an important strategy for Mycobacterium tuberculosis (Mtb) to evade host immune responses. However, it is unknown what role microRNA-144-3p (miR-144-3p) plays in cellular metabolism during Mtb infection. Here, we report the meaning of miR-144-3p-mediated lipid accumulation for Mtb-macrophage interplay. Mtb infection was shown to upregulate the expression of miR-144-3p in macrophages. By targeting peroxisome proliferator-activated receptor α (PPARα) and ATP-binding cassette transporter A1 (ABCA1), miR-144-3p overexpression promoted lipid accumulation and bacterial survival in Mtb-infected macrophages, while miR-144-3p inhibition had the opposite effect. Furthermore, reprogramming of host lipid metabolism by miR-144-3p suppressed autophagy in response to Mtb infection. Our findings uncover that miR-144-3p regulates host metabolism and immune responses to Mtb by targeting PPARα and ABCA1, suggesting a potential host-directed tuberculosis therapy by targeting the interface of miRNA and lipid metabolism.

Pyrroloquinoline quinone supplementation attenuates inflammatory liver injury by STAT3/TGF-β1 pathway in weaned piglets challenged with lipopolysaccharide

This study is aimed to evaluate the effect and underling mechanism of dietary supplementation with pyrroloquinoline quinone (PQQ) disodium on improving inflammatory liver injury in piglets challenged with lipopolysaccharide (LPS). A total of seventy-two crossbred barrows were allotted into four groups as follows: the CTRL group (basal diet + saline injection); the PQQ group (3 mg/kg PQQ diet + saline injection); the CTRL + LPS group (basal diet + LPS injection) and the PQQ + LPS group (3 mg/kg PQQ diet + LPS injection). On days 7, 11 and 14, piglets were challenged with LPS or saline. Blood was sampled at 4 h after the last LPS injection (day 14), and then the piglets were slaughtered and liver tissue was harvested. The results showed that the hepatic morphology was improved in the PQQ + LPS group compared with the CTRL + LPS group. PQQ supplementation decreased the level of serum inflammatory factors, aspartate aminotransferase and alanine transaminase, and increased the HDL-cholesterol concentration in piglets challenged with LPS; piglets in the PQQ + LPS group had lower liver mRNA level of inflammatory factors and protein level of α-smooth muscle actin than in the CTRL + LPS group. Besides, mRNA expression of STAT3/TGF-β1 pathway and protein level of p-STAT3(Tyr 705) were decreased, and mRNA level of PPARα and protein expression of p-AMPK in liver were increased in the PQQ + LPS group compared with the CTRL + LPS group (P < 0·05). In conclusion, dietary supplementation with PQQ alleviated inflammatory liver injury might partly via inhibition of the STAT3/TGF-β1 pathway in piglets challenged with LPS.

Research progress on the role of macrophages in acne and regulation by natural plant products

Acne vulgaris is one of the most common skin diseases. The current understanding of acne primarily revolves around inflammatory responses, sebum metabolism disorders, aberrant hormone and receptor expression, colonization by Cutibacterium acnes, and abnormal keratinization of follicular sebaceous glands. Although the precise mechanism of action remains incompletely understood, it is plausible that macrophages exert an influence on these pathological features. Macrophages, as a constituent of the human innate immune system, typically manifest distinct phenotypes across various diseases. It has been observed that the polarization of macrophages toward the M1 phenotype plays a pivotal role in the pathogenesis of acne. In recent years, extensive research on acne has revealed an increasing number of natural remedies exhibiting therapeutic efficacy through the modulation of macrophage polarization. This review investigates the role of cutaneous macrophages, elucidates their potential significance in the pathogenesis of acne, a prevalent chronic inflammatory skin disorder, and explores the therapeutic mechanisms of natural plant products targeting macrophages. Despite these insights, the precise role of macrophages in the pathogenesis of acne remains poorly elucidated. Subsequent investigations in this domain will further illuminate the pathogenesis of acne and potentially offer guidance for identifying novel therapeutic targets for this condition.

A pan-PPAR agonist E17241 ameliorates hyperglycemia and diabetic dyslipidemia in KKAy mice via up-regulating ABCA1 in islet, liver, and white adipose tissue

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is a common chronic metabolic disease. Peroxisome proliferator-activated receptors (PPARs) play crucial roles in regulating glucolipid metabolism. Previous studies showed that E17241 could ameliorate atherosclerosis and lower fasting blood glucose levels in ApoE-/- mice. In this work, we investigated the role of E17241 in glycolipid metabolism in diabetic KKAy mice.

APPROACH AND RESULTS

We confirmed that E17241 is a powerful pan-PPAR agonist with a potent agonistic activity on PPARγ, a high activity on PPARα, and a moderate activity on PPARδ. E17241 also significantly increased the protein expression of ATP-binding cassette transporter 1 (ABCA1), a crucial downstream target gene for PPARs. E17241 clearly lowered plasma glucose levels, improved OGTT and ITT, decreased islet cholesterol content, improved β-cell function, and promoted insulin secretion in KKAy mice. Moreover, E17241 could significantly lower plasma total cholesterol and triglyceride levels, reduce liver lipid deposition, and improve the adipocyte hypertrophy and the inflammatory response in epididymal white adipose tissue. Further mechanistic studies indicated that E17241 boosts cholesterol efflux and insulin secretion in an ABCA1 dependent manner. RNA-seq and qRT-PCR analysis demonstrated that E17241 induced different expression of PPAR target genes in liver and adipose tissue differently from the PPARγ agonist rosiglitazone. In addition, E17241 treatment was also demonstrated to have an exhilarating cardiorenal benefits.

CONCLUSIONS

Our results demonstrate that E17241 regulates glucolipid metabolism in KKAy diabetic mice while having cardiorenal benefits without inducing weight gain. It is a promising drug candidate for the treatment of T2DM.

Comparative transcriptome analysis reveals potential regulatory mechanisms of genes and immune pathways following Vibrio harveyi infection in red drum (Sciaenops ocellatus)

Red drum (Sciaenops ocellatus), as an important economical marine fish, has been affected by various bacterial diseases in recent years. Vibrio harveyi cause fatal vibriosis in S. ocellatus, leading to massive mortality and causing significant setbacks in aquaculture. However, the regulatory mechanisms of S. ocellatus response to V. harveyi infection are poorly understood. In this regard, we performed transcriptomic analysis with head kidney tissues of S. ocellatus after V. harveyi infection from 12 h to 48 h to reveal genes, gene expression profiles, and pathways involved in immune and inflammation responses. Specifically, a total of 9,599, 5,728, and 7144 differentially expressed genes (DEGs) were identified after V. harveyi infection at 12 h, 24 h, and 48 h, respectively, and 1,848 shared DEGs have been identified from the above three comparison groups. Subsequent pathway analysis revealed that the shared DEGs following V. harveyi were involved in complement and coagulation cascades (C1R, C1QC, C3, C4, C5, C7, C8A, C8B, C8G, C9, CFB, CFH, and CFI), MAPK signaling pathway, chemokine signaling pathway (CCL19, CXCL8, CXCL12, CXCL14, CCR4, CCR7, and CXCR2), PPAR signaling pathway (PPAR-α, PPAR-γ and PPAR-β), and TNF signaling pathway. Finally, the expression patterns of DEGs in head kidney tissues and S. ocellatus macrophages were validated by qRT-PCR, suggesting the reliability of RNA sequencing for gene expression analysis. This dynamic transcriptome analyses provided insights into gene expression regulation and immune related pathways involved in S. ocellatus after V. harveyi infection, and provides useful information for further study on the immune defense mechanisms in S. ocellatus as well as other teleost species.

Investigating the Effect of Aspirin on apoAI-Induced ATP Binding Cassette Transporter 1 Protein Expression and Cholesterol Efflux in Human Astrocytes

Background

Neurons need a high amount of cholesterol to maintain the stability of their membrane-rich structures. Astrocytes synthesize and distribute cholesterol to neurons, and ABCA1 is a key mediator of cholesterol efflux to generate HDL for cholesterol transport in the brain. Several studies imply the effect of aspirin on ABCA1 expression in peripheral cells such as macrophages. Here, we compared the effect of aspirin with apoA-I on ABCA1 protein expression and cholesterol efflux in human astrocytes.

Materials and Methods

Human astrocytes were cultured, and the effects of aspirin on the expression and protein levels of ABCA1 were investigated through RT-PCR and Western blot analysis. Additionally, the effect of co-treatment with apoA-I and aspirin on ABCA1 protein level and cholesterol efflux was evaluated.

Results

Dose and time-course experiments showed that the maximum effect of aspirin on ABCA1 expression occurred at a concentration of 0.5 mM after 12 h of incubation. RT-PCR and western blot data showed that aspirin upregulates ABCA1 expression by up to 4.7-fold and its protein level by 67%. Additionally, co-treatment with aspirin and apoA-I increased cholesterol release from astrocytes, indicating an additive effect of aspirin on apoAI-mediated cholesterol efflux.

Conclusions

The results suggest a potential role of aspirin in increasing ABCA1 expression and cholesterol efflux in astrocytes, similar to the effect of apoA-I. This indicates that aspirin could potentially regulate brain cholesterol balance and can be considered in certain neurological diseases, in particular in some neurological disorders related to cholesterol accumulation such as Alzheimer's disease.

Inhibition of tumor migration and invasion by fenofibrate via suppressing epithelial-mesenchymal transition in breast cancers

The recurrence and metastasis in breast cancer within 3 years after the chemotherapies or surgery leads to poor prognosis with approximately 1-year overall survival. Large-scale scanning research studies have shown that taking lipid-lowering drugs may assist to reduce the risk of death from many cancers, since cholesterol in lipid rafts are essential for maintain integral membrane structure and functional signaling regulation. In this study, we examined five lipid-lowering drugs: swertiamarin, gemfibrozil, clofibrate, bezafibrate, and fenofibrate in triple-negative breast cancer, which is the most migration-prone subtype. Using human and murine triple-negative breast cancer cell lines (Hs 578 t and 4 T1), we found that fenofibrate displays the highest potential in inhibiting the colony formation, wound healing, and transwell migration. We further discovered that fenofibrate reduces the activity of pro-metastatic enzymes, matrix metalloproteinases (MMP)-9 and MMP-2. In addition, epithelial markers including E-cadherin and Zonula occludens-1 are increased, whereas mesenchymal markers including Snail, Twist and α-smooth muscle actin are attenuated. Furthermore, we found that fenofibrate downregulates ubiquitin-dependent GDF-15 degradation, which leads to enhanced GDF-15 expression that inhibits cell migration. Besides, nuclear translocation of FOXO1 is also upregulated by fenofibrate, which may responsible for GDF-15 expression. In summary, fenofibrate with anti-cancer ability hinders TNBC from migration and invasion, and may be beneficial to repurposing use of fenofibrate.

Adiponectin-mediated regulation of the adiponectin cascade in cardiovascular disease: Updates

The endocrine function of white adipose tissue is characterized by the synthesis of one its main hormones: adiponectin. Although the biological role of adiponectin has not been fully defined, clinical and experimental observations have shown that low plasma concentrations of adiponectin participate in the prevalence of insulin resistance and cardiovascular diseases, mainly in obese patients. Adiponectin also exerts its effects on the heart and blood vessels, thereby influencing their physiology. Studying the effects of adiponectin presents some complexities, primarily due to potential cross-interactions and interference with other pathways, such as the AdipoR1/R2 pathways. Under optimal conditions, the activation of the adiponectin cascade may involve signals such as AMPK and PPARα. Interestingly, these pathways may trigger similar responses, such as fatty acid oxidation. Understanding the downstream effectors of these pathways is crucial to comprehend the extent to which adiponectin signaling impacts metabolism. In this review, the aim is to explore the current mechanisms that regulate the adiponectin pathways. Additionally, updates on the major downstream factors involved in adiponectin signaling are provided, specifically in relation to metabolic syndrome and atherosclerosis.

Effects of Heat Stress on Breast Muscle Metabolomics and Lipid Metabolism Related Genes in Growing Broilers

With global warming and worsening climatic conditions, heat stress (HS) has become a significant challenge affecting the development of poultry production. In this study, we aimed to determine the effects of HS on breast muscle metabolomics and lipid metabolism-related genes in growing broilers. One hundred twenty 29-day-old Arbor Acres broilers were randomly divided into normal temperature (NT; 21 ± 1 °C) and heat stress (HS; 31 ± 1 °C) groups, with six replicates (ten birds in each replicate) in each group, raised for 14 days in two environment chambers at 60 ± 7% relative humidity. Compared with the broilers in the NT group, the average daily food intake, average daily gain and breast muscle yield in the HS group were significantly lower (p < 0.05). The feed conversion ratio was significantly higher in the HS group (p < 0.05). The concentrations of serum corticosterone, free fatty acids and cholesterol and the percentage of abdominal fat of broilers in the HS group were significantly higher (p < 0.05) than the values of the broilers in the NT group. Untargeted breast muscle metabolome analysis revealed 14 upregulated differential metabolites, including glycerophosphocholine, and 27 downregulated differential metabolites, including taurine, in the HS group compared to the NT group; the HS group also displayed significant effects on six metabolic pathways compared to the NT group (p < 0.05). The mRNA expression levels of peroxisome proliferator-activated receptor gamma coactivator-1-alpha, peroxisome proliferator-activated receptor alpha (PPARα) and ATP-binding cassette transporter A1 in the liver and breast muscles were significantly decreased in the HS group compared with the NT group (p < 0.05). The collective findings reveal that HS can cause disorders in breast muscle lipid metabolism in broilers. The PPARα gene might be the key gene in the mechanism of the lipid metabolism that is induced by HS in breast muscle of broilers. These findings provide novel insights into the effects of HS on chicken growth.

Ameliorative effect of Lactobacillus plantarum CCFM8661 on oleic acid-induced acne: integrated gut microbiota link to acne pathogenesis

BACKGROUND

Acne vulgaris is an inflammatory disease of the pilosebaceous unit of the skin that has serious adverse effects on the physical and mental health of patients. Probiotics are extensively employed in dermatology and could be an alternative option for acne therapy. Here, we evaluated the effect of oral ingestion of live and inactivated Lactobacillus plantarum CCFM8661 on oleic acid-induced acne using a mouse model.

RESULTS

Results indicated that live L. plantarum CCFM8661 suppressed skin inflammation and serum hormone (insulin and testosterone) production in acne mice. Parallelly, live L. plantarum CCFM8661 effectively reduced the formation of skin lipids (triglycerides and non-esterified free fatty acids), and normalized the expression of skin lipid metabolism-related genes (PPAR-γ, SREBP-1c, ACCα, FASN, PPAR-α, ACOX1, HSL and ATGL). In comparison, inactivated L. plantarum CCFM8661 had no effect on skin inflammation or serum hormone secretion, but decreased skin triglycerides and normalized the expression of skin lipid metabolism-related genes (PPAR-γ, SREBP-1c, FASN and ATGL) in acne mice. Both live and inactivated L. plantarum CCFM8661 raised the richness of gut microbiota, reduced the ratio of Bacteroidetes to Firmicutes and decreased the relative abundance of Staphylococcus in the feces of acne mice.

CONCLUSION

Oral ingestion of L. plantarum CCFM8661, particularly live cells, could alleviate acne by suppressing skin inflammation, normalizing the metabolism of hormones and skin lipids, which may be achieved by improving the gut microbial ecosystem. © 2023 Society of Chemical Industry.

Peroxisome proliferator-activated receptorα/γ agonist pioglitazone for rescuing relapsed or refractory neoplasias by unlocking phenotypic plasticity

A series of seven clinical trials on relapsed or refractory (r/r) metastatic neoplasias followed the question: Are networks of ligand-receptor cross-talks that support tumor-specific cancer hallmarks, druggable with tumor tissue editing approaches therapeutically exploiting tumor plasticity? Differential recombinations of pioglitazone, a dual peroxisome-proliferator activated receptorα/γ (PPARα/γ) agonist, with transcriptional modulators, i.e., all-trans retinoic acid, interferon-α, or dexamethasone plus metronomic low-dose chemotherapy (MCT) or epigenetic modeling with azacitidine plus/minus cyclooxygenase-2 inhibition initiated tumor-specific reprogramming of cancer hallmarks, as exemplified by inflammation control in r/r melanoma, renal clear cell carcinoma (RCCC), Hodgkin's lymphoma (HL) and multisystem Langerhans cell histiocytosis (mLCH) or differentiation induction in non-promyelocytic acute myeloid leukemia (non-PML AML). Pioglitazone, integrated in differentially designed editing schedules, facilitated induction of tumor cell death as indicated by complete remission (CR) in r/r non-PML AML, continuous CR in r/r RCCC, mLCH, and in HL by addition of everolimus, or long-term disease control in melanoma by efficaciously controlling metastasis, post-therapy cancer repopulation and acquired cell-resistance and genetic/molecular-genetic tumor cell heterogeneity (M-CRAC). PPARα/γ agonists provided tumor-type agnostic biomodulatory efficacy across different histologic neoplasias. Tissue editing techniques disclose that wide-ranging functions of PPARα/γ agonists may be on-topic focused for differentially unlocking tumor phenotypes. Low-dose MCT facilitates targeted reprogramming of cancer hallmarks with transcriptional modulators, induction of tumor cell death, M-CRAC control and editing of non-oncogene addiction. Thus, pioglitazone, integrated in tumor tissue editing protocols, is an important biomodulatory drug for addressing urgent therapeutic problems, such as M-CRAC in relapsed or refractory tumor disease.

In-silico Assessment of Polyherbal Oils as Anti-diabetic Therapeutics

BACKGROUND

Diabetes mellitus (DM) is characterized by elevated blood glucose levels either due to insufficient insulin production, defective insulin action, or both. It affects nearly 537 million individuals worldwide. Pharmacological treatment involves the use of oral antidiabetic agents as mono or combination therapy that effectively aids in controlling hyperglycemia. Despite providing therapeutic benefits, these medications limit their use owing to adverse side effects. Certain natural products, including essential oils, have promising anti-diabetic properties.

OBJECTIVE

The present study explores the effectiveness of two polyherbal oils and their compound towards the treatment of DM based on an In-silico approach to drug investigations Methods: Compounds present in the polyherbal oil formulation were identified using GCMS/ MS analysis. Selected compounds undergo molecular docking with the receptor, and proteins play an important role in DM. The potential compounds showing higher interactions than the known inhibitors or inducers were evaluated using molecular dynamic simulations RMSD value.

RESULTS

The compounds identified through GC-MS analysis possess anti-diabetic and antiinflammatory properties. With the aid of in silico prediction methods, compounds such as geraniol, cinnamaldehyde, anethole, caryophyllene, terpinyl acetate, cymene, linalool, menthol, Phenol,2-methoxy-3-(2-propenyl), and 2,6- octadienal,3,7-dimethyl were identified as strong binders of GLUT4 and insulin receptor proteins. Geraniol and Phenol,2-methoxy-3-(2-propenyl) interaction with GLUT4 were of particular importance owing to their conformational stability.

CONCLUSION

Our data suggest an agonistic effect of compounds on target proteins aiding in enhanced insulin activity and could serve as a potential anti-diabetic agent.

N-Stearoylethanolamine Exerts Cardioprotective Effects in Old Rats

BACKGROUND

Aging is associated with the slowing down of metabolic processes, diminished physiological processes, changes in hormonal activity and increasing exposure to oxidative stress factors and chronic inflammation. The endocannabinoid system (ECS) is a major signaling network that plays a pro-homeostatic role in the central and peripheral organs of the human body. A class of minor lipids, N-acylethanolamines (NAEs), which do not activate cannabinoid receptors, except for anandamide, but can potentiate the action of endocannabinoids and have a wide spectrum of biological activity and significant adaptogenic potential, belongs to ECS. The results of different studies over the past decades have established the protective effect of NAE on many pathological conditions.

OBJECTIVE

This study aimed to investigate the cardioprotective effects of C18:0 NAE- N-stearoylethanolamine (NSE) in aged rats. In this study, we focused on investigating the effects of C18:0 NAE- N-stearoylethanolamine (NSE) on the intensity of oxidative/ nitrosative stress, antioxidant potential, lipoprotein profile and inflammation markers of blood plasma, phospholipid composition and age-related morphological changes of old rat heart tissues.

METHODS

The study was conducted on Sprague Dawley male laboratory rats. The three groups of rats were involved in the study design. The first group consisted of young rats aged 4 months (n=10). The second (n=10) and third (n=10) groups included old rats aged of 18 months. Rats from the third group were administered a per os aqueous suspension of NSE at a dose of 50 mg/kg of body weight daily for 10 days. All groups of rats were kept on a standard vivarium diet. The blood plasma, serum, and heart of rats were used for biochemical and histological analysis.

RESULTS

The cardioprotective effect of N-stearoylethanolamine in old rats was established, which was expressed in the normalization of the antioxidant system condition and the level of proinflammatory cytokines, positive modulation of blood plasma and lipoprotein profile, normalization of heart tissue lipid composition, and significant reduction in age-related myocardium morphological changes.

CONCLUSION

The revealed effects of N-stearoylethanolamine can become the basis for developing a new drug for use in complex therapy to improve the quality of life of older people.

Reexamining the Causes and Effects of Cholesterol Deposition in the Brains of Patients with Alzheimer's Disease

Alzheimer's disease (AD) is a degenerative disease of the central nervous system. Numerous studies have shown that imbalances in cholesterol homeostasis in the brains of AD patients precede the onset of clinical symptoms. In addition, cholesterol deposition has been observed in the brains of AD patients even though peripheral cholesterol does not enter the brain through the blood‒brain barrier (BBB). Studies have demonstrated that cholesterol metabolism in the brain is associated with many pathological conditions, such as amyloid beta (Aβ) production, Tau protein phosphorylation, oxidative stress, and inflammation. In 2022, some scholars put forward a new hypothesis of AD: the disease involves lipid invasion and its exacerbation of the abnormal metabolism of cholesterol in the brain. In this review, by discussing the latest research progress, the causes and effects of cholesterol retention in the brains of AD patients are analyzed and discussed. Additionally, the possible mechanism through which AD may be improved by targeting cholesterol is described. Finally, we propose that improving the impairments in cholesterol removal observed in the brains of AD patients, instead of further reducing the already impaired cholesterol synthesis in the brain, may be the key to preventing cholesterol deposition and improving the corresponding pathological symptoms.

Empagliflozin treatment of cardiotoxicity: A comprehensive review of clinical, immunobiological, neuroimmune, and therapeutic implications

Cancer and cardiovascular disorders are known as the two main leading causes of mortality worldwide. Cardiotoxicity is a critical and common adverse effect of cancer-related chemotherapy. Chemotherapy-induced cardiotoxicity has been associated with various cancer treatments, such as anthracyclines, immune checkpoint inhibitors, and kinase inhibitors. Different methods have been reported for the management of chemotherapy-induced cardiotoxicity. In this regard, sodium-glucose cotransporter-2 inhibitors (SGLT2i), a class of antidiabetic agents, have recently been applied to manage heart failure patients. Further, SGLT2i drugs such as EMPA exert protective cardiac and systemic effects. Moreover, it can reduce inflammation through the mediation of major inflammatory components, such as Nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasomes, Adenosine 5'-monophosphate-activated protein kinase (AMPK), and c-Jun N-terminal kinase (JNK) pathways, Signal transducer and activator of transcription (STAT), and overall decreasing transcription of proinflammatory cytokines. The clinical outcome of EMPA administration is related to improving cardiovascular risk factors, including body weight, lipid profile, blood pressure, and arterial stiffness. Intriguingly, SGLT2 suppressors can regulate microglia-driven hyperinflammation affecting neurological and cardiovascular disorders. In this review, we discuss the protective effects of EMPA in chemotherapy-induced cardiotoxicity from molecular, immunological, and neuroimmunological aspects to preclinical and clinical outcomes.

Chronic inflammatory effects of in vivo irradiation of the murine heart on endothelial cells mimic mechanisms involved in atherosclerosis

PURPOSE

Radiotherapy is a major pillar in the treatment of solid tumors including breast cancer. However, epidemiological studies have revealed an increase in cardiac diseases approximately a decade after exposure of the thorax to ionizing irradiation, which might be related to vascular inflammation. Therefore, chronic inflammatory effects were examined in primary heart and lung endothelial cells (ECs) of mice after local heart irradiation.

METHODS

Long-lasting effects on primary ECs of the heart and lung were studied 20-50 weeks after local irradiation of the heart of mice (8 and 16 Gy) in vivo by multiparameter flow cytometry using antibodies directed against cell surface markers related to proliferation, stemness, lipid metabolism, and inflammation, and compared to those induced by occlusion of the left anterior descending coronary artery.

RESULTS

In vivo irradiation of the complete heart caused long-lasting persistent upregulation of inflammatory (HCAM, ICAM‑1, VCAM-1), proliferation (CD105), and lipid (CD36) markers on primary heart ECs and an upregulation of ICAM‑1 and VCAM‑1 on primary ECs of the partially irradiated lung lobe. An artificially induced heart infarction induces similar effects with respect to inflammatory markers, albeit in a shorter time period.

CONCLUSION

The long-lasting upregulation of prominent inflammatory markers on primary heart and lung ECs suggests that local heart irradiation induces chronic inflammation in the microvasculature of the heart and partially irradiated lung that leads to cardiac injury which might be related to altered lipid metabolism in the heart.

Atheroprotective Effect of Fucoidan in THP-1 Macrophages by Potential Upregulation of ABCA1

Targeting foam cells reduces the risk and pathophysiology of atherosclerosis, of which they are one of its early hallmarks. The precise mechanism of action of fucoidan, a potential anti-atherogenic drug, is still unknown. Our objective was to assess the ability of fucoidan to regulate expression of ATP-binding cassette transporter A1 (ABCA1) in ox-LDL-induced THP-1 macrophages. Molecular docking was used to predict how fucoidan interacts with anti-foam cell markers, and further in vitro experiments were performed to evaluate the protective effect of fucoidan on modulating uptake and efflux of lipids. THP-1 macrophages were protected by 50 µg/mL of fucoidan and were then induced to form foam cells with 25 µg/mL of ox-LDL. Expression levels were assessed using RT-qPCR, and an Oil Red O stain was used to observe lipid accumulation in THP-1 macrophages. In addition, ABCA1 protein was examined by Western blot, and cellular cholesterol efflux was determined using fluorescently labeled cholesterol. Under a light microscope, decreased lipid accumulation in ox-LDL-induced-THP-1 macrophages pre-treated with fucoidan showed a significant effect, although it did not affect the expression of scavenger receptors (SR-AI and CD36). It is interesting to note that fucoidan dramatically increased the gene and protein expression of ABCA1, perhaps via the liver X receptor-α (LXR-α). Moreover, fucoidan's ability to increase and control the efflux of cholesterol from ox-LDL-induced THP-1 macrophages revealed how it may alter ABCA1's conformation and have a major effect on how it interacts with apolipoprotein A (ApoA1). In vitro results support a rationale for predicting fucoidan and its interaction with its receptor targets' predicted data, hence validating its anti-atherogenic properties and suggesting that fucoidan could be promising as an atheroprotective.

Drug repurposing by in silico prediction of cyclizine derivatives as antihyperlipemic agents

Cardiovascular diseases are the primary factor for increased mortality rates around the world. Atherosclerosis brought on by high serum cholesterol can result in coronary heart disease (CHD). The risk of CHD is markedly reduced by lowering serum cholesterol levels. Scientists across the world are inventing new treatment regimens for lowering blood lipid levels. In this work, we repurposed the already established drugs, i.e., cyclizine derivatives as antihyperlipidemic agents. The repurposing was done based on the similarity of the selected cyclizine derivatives with the already established antihyperlipidemic drug, fenofibrate. Computational studies were performed and the 16 cyclizine derivatives docked against PPAR. alpha scored higher than fenofibrate. Lifarizine and medibazine outperform fenofibrate inmmgbsa. Fenofibrate, etodroxizine, meclizine, and cinnarizine had similar mmgbsa scores. The ADME properties of these compounds were performed and from that etodroxizine and levocetirizine were found to have better properties. The computational studies were performed using the Schrodinger software, maestro 12.8. The "Protein Preparation Wizard" module in the Maestro panel was used to create the protein structure and OPLS4 force field was used for energy minimization. The maestro builder panel's "Ligprep", "Receptor Grid Generation" and "Ligand Docking" modules were then used to prepare ligands, receptor grids and to perform docking respectively. MMGBSA was performed on the "prime MMGBSA" segment. Using the "Qikprop" setting in the maestro panel, a number of ADMET properties were predicted, and the program was run in default mode using vsgb as the solvation model.

Metabolic-Dysfunction-Associated Steatotic Liver Disease-Its Pathophysiology, Association with Atherosclerosis and Cardiovascular Disease, and Treatments

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a chronic liver disease that affects more than a quarter of the global population and whose prevalence is increasing worldwide due to the pandemic of obesity. Obesity, impaired glucose metabolism, high blood pressure and atherogenic dyslipidemia are risk factors for MASLD. Therefore, insulin resistance may be closely associated with the development and progression of MASLD. Hepatic entry of increased fatty acids released from adipose tissue, increase in fatty acid synthesis and reduced fatty acid oxidation in the liver and hepatic overproduction of triglyceride-rich lipoproteins may induce the development of MASLD. Since insulin resistance also induces atherosclerosis, the leading cause for death in MASLD patients is cardiovascular disease. Considering that the development of cardiovascular diseases determines the prognosis of MASLD patients, the therapeutic interventions for MASLD should reduce body weight and improve coronary risk factors, in addition to an improving in liver function. Lifestyle modifications, such as improved diet and increased exercise, and surgical interventions, such as bariatric surgery and intragastric balloons, have shown to improve MASLD by reducing body weight. Sodium glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been shown to improve coronary risk factors and to suppress the occurrence of cardiovascular diseases. Both SGLT2i and GLP-1 have been reported to improve liver enzymes, hepatic steatosis and fibrosis. We recently reported that the selective peroxisome proliferator-activated receptor-alpha (PPARα) modulator pemafibrate improved liver function. PPARα agonists have multiple anti-atherogenic properties. Here, we consider the pathophysiology of MASLD and the mechanisms of action of such drugs and whether such drugs and the combination therapy of such drugs could be the treatments for MASLD.

RAE1 promotes nitrosamine-induced malignant transformation of human esophageal epithelial cells through PPARα-mediated lipid metabolism

Esophageal cancer (EC) is the sixth cause of cancer-related deaths and still is a significant public health problem globally. Nitrosamines exposure represents a major health concern increasing EC risks. Exploring the mechanisms induced by nitrosamines may contribute to the prevention and early detection of EC. However, the mechanism of nitrosamine carcinogenesis remains unclear. Ribonucleic acid export 1 (RAE1), has an important role in mediating diverse cancer types, but, to date, there has been no study for any functional role of RAE1 in esophageal carcinogenesis. Here, we successfully verified the nitrosamine-induced malignant transformation cell (MNNG-M) by xenograft tumor model, based on which it was found that RAE1 was upregulation in the early stage of nitrosamine-induced esophageal carcinogenesis and EC tissues. RAE1 knockdown led to severe blockade in G2/M phase and significant inhibition of proliferation of MNNG-M cells, whereas RAE1 overexpression had the opposite effect. In addition, peroxisome proliferator-activated receptor-alpha (PPARα), was demonstrated as a downstream target gene of RAE1, and its down-regulation reduced lipid accumulation, resulting in causing cells accumulation in the G2/M phase. Mechanistically, we found that RAE1 regulates the lipid metabolism by maintaining the stability of PPARα mRNA. Taken together, our study reveals that RAE1 promotes malignant transformation of human esophageal epithelial cells (Het-1A) by regulating PPARα-mediated lipid metabolism to affect cell cycle progression, and offers a new explanation of the mechanisms underlying esophageal carcinogenesis.

Peroxisome Proliferator-Activated Receptor α in Lipoprotein Metabolism and Atherosclerotic Cardiovascular Disease

Peroxisome proliferator-activated receptors (PPARs) are a group of ligand-binding transcription factors with pivotal action in regulating pleiotropic signaling pathways of energetic metabolism, immune responses and cell proliferation and differentiation. A significant body of evidence indicates that the PPARα receptor is an important modulator of plasma lipid and lipoprotein metabolism, with pluripotent effects influencing the lipid and apolipoprotein cargo of both atherogenic and antiatherogenic lipoproteins and their functionality. Clinical evidence supports an important role of PPARα agonists (fibric acid derivatives) in the treatment of hypertriglyceridemia and/or low high-density lipoprotein (HDL) cholesterol levels, although the effects of clinical trials are contradictory and point to a reduction in the risk of nonfatal and fatal myocardial infarction events. In this manuscript, we provide an up-to-date critical review of the existing relevant literature.

Molecular, metabolic, and functional CD4 T cell paralysis in the lymph node impedes tumor control

CD4 T cells are central effectors of anti-cancer immunity and immunotherapy, yet the regulation of CD4 tumor-specific T (TTS) cells is unclear. We demonstrate that CD4 TTS cells are quickly primed and begin to divide following tumor initiation. However, unlike CD8 TTS cells or exhaustion programming, CD4 TTS cell proliferation is rapidly frozen in place by a functional interplay of regulatory T cells and CTLA4. Together these mechanisms paralyze CD4 TTS cell differentiation, redirecting metabolic circuits, and reducing their accumulation in the tumor. The paralyzed state is actively maintained throughout cancer progression and CD4 TTS cells rapidly resume proliferation and functional differentiation when the suppressive constraints are alleviated. Overcoming their paralysis established long-term tumor control, demonstrating the importance of rapidly crippling CD4 TTS cells for tumor progression and their potential restoration as therapeutic targets.

Chromogranin A and its derived peptides: potential regulators of cholesterol homeostasis

Chromogranin A (CHGA), a member of the granin family of proteins, has been an attractive therapeutic target and candidate biomarker for several cardiovascular, neurological, and inflammatory disorders. The prominence of CHGA stems from the pleiotropic roles of several bioactive peptides (e.g., catestatin, pancreastatin, vasostatins) generated by its proteolytic cleavage and by their wide anatomical distribution. These peptides are emerging as novel modulators of cardiometabolic diseases that are often linked to high blood cholesterol levels. However, their impact on cholesterol homeostasis is poorly understood. The dynamic nature of cholesterol and its multitudinous roles in almost every aspect of normal body function makes it an integral component of metabolic physiology. A tightly regulated coordination of cholesterol homeostasis is imperative for proper functioning of cellular and metabolic processes. The deregulation of cholesterol levels can result in several pathophysiological states. Although studies till date suggest regulatory roles for CHGA and its derived peptides on cholesterol levels, the mechanisms by which this is achieved still remain unclear. This review aims to aggregate and consolidate the available evidence linking CHGA with cholesterol homeostasis in health and disease. In addition, we also look at common molecular regulatory factors (viz., transcription factors and microRNAs) which could govern the expression of CHGA and genes involved in cholesterol homeostasis under basal and pathological conditions. In order to gain further insights into the pathways mediating cholesterol regulation by CHGA/its derived peptides, a few prospective signaling pathways are explored, which could act as primers for future studies.

FNDC5 Attenuates Atherosclerotic Plaque Formation and Regulates PPARα/HO-1 in ApoE-/- Mice

INTRODUCTION

This study attempted to observe the role of fibronectin type III domain-containing protein 5 (FNDC5) in atherosclerosis development and the underlying mechanism.

METHODS

After being fed a high-fat diet (HFD), ApoE-/- mice were injected with saline, control adenovirus (Ad-vector), or FNDC5 overexpressing adenovirus (Ad-FNDC5). ApoE-/- mice fed with a chow diet were considered the control. After 12 weeks of treatment, the levels of serum high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and irisin were detected by commercial kits.

RESULTS

Compared with the control, the serum TG, TC, and LDL-C levels, aortic plaque area, and weight were significantly increased, while serum HDL-C and irisin levels were reduced in HFD mice. Treating with Ad-FNDC5 could alleviate these changes in HFD mice and cause the activation of PPARα/HO-1 signaling in aortic tissue. After co-treating with GW6471, a PPARα antagonist, the effects of Ad-FNDC5 on the weight, serum LDL-C, TC, TG, and HDL-C levels, and aortic plaque of HFD mice were partly blocked.

CONCLUSION

Elevated FNDC5 has a delaying effect on atherosclerotic plaque formation, which may be related to the upregulation of PPARα/HO-1 signaling.

Impact of Lipid Metabolism on Macrophage Polarization: Implications for Inflammation and Tumor Immunity

Macrophage polarization is influenced by lipids, which also exert significant control over macrophage functions. Lipids and their metabolites are players in intricate signaling pathways that modulate macrophages' responses to pathogens, phagocytosis, ferroptosis, and inflammation. This review focuses on lipid metabolism and macrophage functions and addresses potential molecular targets for the treatment of macrophage-related diseases. While lipogenesis is crucial for lipid accumulation and phagocytosis in M1 macrophages, M2 macrophages likely rely on fatty acid β-oxidation to utilize fatty acids as their primary energy source. Cholesterol metabolism, regulated by factors such as SREBPs, PPARs, and LXRs, is associated with the cholesterol efflux capacity and the formation of foam cells (M2-like macrophages). Foam cells, which are targets for atherosclerosis, are associated with an increase in inflammatory cytokines. Lipolysis and fatty acid uptake markers, such as CD36, also contribute to the production of cytokines. Enhancing the immune system through the inhibition of lipid-metabolism-related factors can potentially serve as a targeted approach against tumor cells. Cyclooxygenase inhibitors, which block the conversion of arachidonic acid into various inflammatory mediators, influence macrophage polarization and have generated attention in cancer research.

Silica nanoparticles promoted pro-inflammatory macrophage and foam cell transformation via ROS/PPARγ/NF-κB signaling

Experimental evidence has pointed out silica nanoparticles (SiNPs) possessing a proatherogenic capability. However, the interplay between SiNPs and macrophages in the pathogenesis of atherosclerosis was poorly understood. Here, we demonstrated SiNPs could promote macrophage adhesion to endothelial cells, accompanied by elevated Vcam1 and Mcp1. Upon SiNPs stimuli, macrophages manifested enhanced phagocytic activity and a pro-inflammatory phenotype, as reflected by the transcriptional determination of M1/M2-related biomarkers. In particular, our data certified the increased macrophage M1 subset facilitated more lipid accumulation and resultant foam cell transformation in comparison to the M2 phenotype. More importantly, the mechanistic investigations revealed ROS-mediated PPARγ/NF-κB signaling was a key contributor to the above phenomena. That was, SiNPs caused ROS accumulation in macrophages, resulting in the deactivation of PPARγ, nuclear translocation of NF-κB, ultimately contributing to macrophage phenotype shift toward M1 and foam cell transformation. Collectively, we first revealed SiNPs facilitated pro-inflammatory macrophage and foam cell transformation via ROS/PPARγ/NF-κB signaling. These data would provide new insight into the atherogenic property of SiNPs in a macrophage model.

Lipid-laden foam cells in the pathology of atherosclerosis: shedding light on new therapeutic targets

INTRODUCTION

Lipid-laden foam cells within atherosclerotic plaques are key players in all phases of lesion development including its progression, necrotic core formation, fibrous cap thinning, and eventually plaque rupture. Manipulating foam cell biology is thus an attractive therapeutic strategy at early, middle, and even late stages of atherosclerosis. Traditional therapies have focused on prevention, especially lowering plasma lipid levels. Despite these interventions, atherosclerosis remains a major cause of cardiovascular disease, responsible for the largest numbers of death worldwide.

AREAS COVERED

Foam cells within atherosclerotic plaques are comprised of macrophages, vascular smooth muscle cells, and other cell types which are exposed to high concentrations of lipoproteins accumulating within the subendothelial intimal layer. Macrophage-derived foam cells are particularly well studied and have provided important insights into lipid metabolism and atherogenesis. The contributions of foam cell-based processes are discussed with an emphasis on areas of therapeutic potential and directions for drug development.

EXERT OPINION

As key players in atherosclerosis, foam cells are attractive targets for developing more specific, targeted therapies aimed at resolving atherosclerotic plaques. Recent advances in our understanding of lipid handling within these cells provide insights into how they might be manipulated and clinically translated to better treat atherosclerosis.

Role of PPARγ in dyslipidemia and altered pulmonary functioning in mice following ozone exposure

Exposure to ozone causes decrements in pulmonary function, a response associated with alterations in lung lipids. Pulmonary lipid homeostasis is dependent on the activity of peroxisome proliferator activated receptor gamma (PPARγ), a nuclear receptor that regulates lipid uptake and catabolism by alveolar macrophages (AMs). Herein, we assessed the role of PPARγ in ozone-induced dyslipidemia and aberrant lung function in mice. Exposure of mice to ozone (0.8 ppm, 3 h) resulted in a significant reduction in lung hysteresivity at 72 h post exposure; this correlated with increases in levels of total phospholipids, specifically cholesteryl esters, ceramides, phosphatidylcholines, phosphorylethanolamines, sphingomyelins, and di- and triacylglycerols in lung lining fluid. This was accompanied by a reduction in relative surfactant protein-B (SP-B) content, consistent with surfactant dysfunction. Administration of the PPARγ agonist, rosiglitazone (5 mg/kg/day, i.p.) reduced total lung lipids, increased relative amounts of SP-B, and normalized pulmonary function in ozone-exposed mice. This was associated with increases in lung macrophage expression of CD36, a scavenger receptor important in lipid uptake and a transcriptional target of PPARγ. These findings highlight the role of alveolar lipids as regulators of surfactant activity and pulmonary function following ozone exposure and suggest that targeting lipid uptake by lung macrophages may be an efficacious approach for treating altered respiratory mechanics.

Alveolar macrophages in pulmonary alveolar proteinosis: origin, function, and therapeutic strategies

Pulmonary alveolar proteinosis (PAP) is a rare pulmonary disorder that is characterized by the abnormal accumulation of surfactant within the alveoli. Alveolar macrophages (AMs) have been identified as playing a pivotal role in the pathogenesis of PAP. In most of PAP cases, the disease is triggered by impaired cholesterol clearance in AMs that depend on granulocyte-macrophage colony-stimulating factor (GM-CSF), resulting in defective alveolar surfactant clearance and disruption of pulmonary homeostasis. Currently, novel pathogenesis-based therapies are being developed that target the GM-CSF signaling, cholesterol homeostasis, and immune modulation of AMs. In this review, we summarize the origin and functional role of AMs in PAP, as well as the latest therapeutic strategies aimed at addressing this disease. Our goal is to provide new perspectives and insights into the pathogenesis of PAP, and thereby identify promising new treatments for this disease.

Roles and regulation of microglia activity in multiple sclerosis: insights from animal models

As resident macrophages of the CNS, microglia are critical immune effectors of inflammatory lesions and associated neural dysfunctions. In multiple sclerosis (MS) and its animal models, chronic microglial inflammatory activity damages myelin and disrupts axonal and synaptic activity. In contrast to these detrimental effects, the potent phagocytic and tissue-remodelling capabilities of microglia support critical endogenous repair mechanisms. Although these opposing capabilities have long been appreciated, a precise understanding of their underlying molecular effectors is only beginning to emerge. Here, we review recent advances in our understanding of the roles of microglia in animal models of MS and demyelinating lesions and the mechanisms that underlie their damaging and repairing activities. We also discuss how the structured organization and regulation of the genome enables complex transcriptional heterogeneity within the microglial cell population at demyelinating lesions.

Targeting PPARs for therapy of atherosclerosis: A review

Atherosclerosis, a chief pathogenic factor of cardiovascular disease, is associated with many factors including inflammation, dyslipidemia, and oxidative stress. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors and are widely expressed with tissue- and cell-specificity. They control multiple genes that are involved in lipid metabolism, inflammatory response, and redox homeostasis. Given the diverse biological functions of PPARs, they have been extensively studied since their discovery in 1990s. Although controversies exist, accumulating evidence have demonstrated that PPAR activation attenuates atherosclerosis. Recent advances are valuable for understanding the mechanisms of action of PPAR activation. This article reviews the recent findings, mainly from the year of 2018 to present, including endogenous molecules in regulation of PPARs, roles of PPARs in atherosclerosis by focusing on lipid metabolism, inflammation, and oxidative stress, and synthesized PPAR modulators. This article provides information valuable for researchers in the field of basic cardiovascular research, for pharmacologists that are interested in developing novel PPAR agonists and antagonists with lower side effects as well as for clinicians.

Novel Selective PPARα Modulator Pemafibrate for Dyslipidemia, Nonalcoholic Fatty Liver Disease (NAFLD), and Atherosclerosis

Statins, the intestinal cholesterol transporter inhibitor (ezetimibe), and PCSK9 inhibitors can reduce serum LDL-C levels, leading to a significant reduction in cardiovascular events. However, these events cannot be fully prevented even when maintaining very low LDL-C levels. Hypertriglyceridemia and reduced HDL-C are known as residual risk factors for ASCVD. Hypertriglyceridemia and/or low HDL-C can be treated with fibrates, nicotinic acids, and n-3 polyunsaturated fatty acids. Fibrates were demonstrated to be PPARα agonists and can markedly lower serum TG levels, yet were reported to cause some adverse effects, including an increase in the liver enzyme and creatinine levels. Recent megatrials of fibrates have shown negative findings on the prevention of ASCVD, which were supposed to be due to their low selectivity and potency for binding to PPAR α. To overcome the off-target effects of fibrates, the concept of a selective PPARα modulator (SPPARMα) was proposed. Kowa Company, Ltd. (Tokyo, Japan), has developed pemafibrate (K-877). Compared with fenofibrate, pemafibrate showed more favorable effects on the reduction of TG and an increase in HDL-C. Fibrates worsened liver and kidney function test values, although pemafibrate showed a favorable effect on liver function test values and little effect on serum creatinine levels and eGFR. Minimal drug-drug interactions of pemafibrate with statins were observed. While most of the fibrates are mainly excreted from the kidney, pemafibrate is metabolized in the liver and excreted into the bile. It can be used safely even in patients with CKD, without a significant increase in blood concentration. In the megatrial of pemafibrate, PROMINENT, for dyslipidemic patients with type 2 diabetes, mild-to-moderate hypertriglyceridemia, and low HDL-C and LDL-C levels, the incidence of cardiovascular events did not decrease among those receiving pemafibrate compared to those receiving the placebo; however, the incidence of nonalcoholic fatty liver disease was lower. Pemafibrate may be superior to conventional fibrates and applicable to CKD patients. This current review summarizes the recent findings on pemafibrate.

Molecular, metabolic and functional CD4 T cell paralysis impedes tumor control

CD4 T cells are important effectors of anti-tumor immunity, yet the regulation of CD4 tumor-specific T (T TS ) cells during cancer development is still unclear. We demonstrate that CD4 T TS cells are initially primed in the tumor draining lymph node and begin to divide following tumor initiation. Distinct from CD8 T TS cells and previously defined exhaustion programs, CD4 T TS cell proliferation is rapidly frozen in place and differentiation stunted by a functional interplay of T regulatory cells and both intrinsic and extrinsic CTLA4 signaling. Together these mechanisms paralyze CD4 T TS cell differentiation, redirecting metabolic and cytokine production circuits, and reducing CD4 T TS cell accumulation in the tumor. Paralysis is actively maintained throughout cancer progression and CD4 T TS cells rapidly resume proliferation and functional differentiation when both suppressive reactions are alleviated. Strikingly, Treg depletion alone reciprocally induced CD4 T TS cells to themselves become tumor-specific Tregs, whereas CTLA4 blockade alone failed to promote T helper differentiation. Overcoming their paralysis established long-term tumor control, demonstrating a novel immune evasion mechanism that specifically cripples CD4 T TS cells to favor tumor progression.

Melatonin inhibits bladder tumorigenesis by suppressing PPARγ/ENO1-mediated glycolysis

Melatonin is a well-known natural hormone, which shows a potential anticancer effect in many human cancers. Bladder cancer (BLCA) is one of the most malignant human cancers in the world. Chemoresistance is an increasingly prominent phenomenon that presents an obstacle to the clinical treatment of BLCA. There is an urgent need to investigate novel drugs to improve the current clinical status. In our study, we comprehensively explored the inhibitory effect of melatonin on BLCA and found that it could suppress glycolysis process. Moreover, we discovered that ENO1, a glycolytic enzyme involved in the ninth step of glycolysis, was the downstream effector of melatonin and could be a predictive biomarker of BLCA. We also proved that enhanced glycolysis simulated by adding exogenous pyruvate could induce gemcitabine resistance, and melatonin treatment or silencing of ENO1 could intensify the cytotoxic effect of gemcitabine on BLCA cells. Excessive accumulation of reactive oxygen species (ROS) mediated the inhibitory effect of melatonin on BLCA cells. Additionally, we uncovered that PPARγ was a novel upstream regulator of ENO1, which mediated the downregulation of ENO1 caused by melatonin. Our study offers a fresh perspective on the anticancer effect of melatonin and encourages further studies on clinical chemoresistance.

A comparative gene expression matrix in Apoe-deficient mice identifies unique and atherosclerotic disease stage-specific gene regulation patterns in monocytes and macrophages

BACKGROUND AND AIMS

Atherosclerosis is a systemic and chronic inflammatory disease propagated by monocytes and macrophages. Yet, our knowledge on how transcriptome of these cells evolves in time and space is limited. We aimed at characterizing gene expression changes in site-specific macrophages and in circulating monocytes during the course of atherosclerosis.

METHODS

We utilized apolipoprotein E-deficient mice undergoing one- and six-month high cholesterol diet to model early and advanced atherosclerosis. Aortic macrophages, peritoneal macrophages, and circulating monocytes from each mouse were subjected to bulk RNA-sequencing (RNA-seq). We constructed a comparative directory that profiles lesion- and disease stage-specific transcriptomic regulation of the three cell types in atherosclerosis. Lastly, the regulation of one gene, Gpnmb, whose expression positively correlated with atheroma growth, was validated using single-cell RNA-seq (scRNA-seq) of atheroma plaque from murine and human.

RESULTS

The convergence of gene regulation between the three investigated cell types was surprisingly low. Overall 3245 differentially expressed genes were involved in the biological modulation of aortic macrophages, among which less than 1% were commonly regulated by the remote monocytes/macrophages. Aortic macrophages regulated gene expression most actively during atheroma initiation. Through complementary interrogation of murine and human scRNA-seq datasets, we showcased the practicality of our directory, using the selected gene, Gpnmb, whose expression in aortic macrophages, and a subset of foamy macrophages in particular, strongly correlated with disease advancement during atherosclerosis initiation and progression.

CONCLUSIONS

Our study provides a unique toolset to explore gene regulation of macrophage-related biological processes in and outside the atheromatous plaque at early and advanced disease stages.

[State of the art on the pathophysiology, diagnosis and treatment of non-alcoholic steatohepatitis (NASH)]

NAFLD or non-alcoholic fatty liver disease is one of the complications of obesity and diabetes, the prevalence of which is increasing. The causes of the pathology and its development towards its severe form, NASH or non-alcoholic steatohepatitis, are multiple and still poorly understood. Many different pharmacological classes are being tested in clinical trials to treat NASH, but no pharmaceutical treatment is currently on the market. Moreover, the diagnosis of certainty is only possible by liver biopsy and histological analysis, an invasive procedure with high risk for the patient. It is therefore necessary to better understand the natural history of the disease in order to identify therapeutic targets, but also to identify markers for the diagnosis and monitoring of the disease using a blood sample, which will allow an improvement in patient management.

MeCP2 Is an Epigenetic Factor That Links DNA Methylation with Brain Metabolism

DNA methylation, one of the most well-studied epigenetic modifications, is involved in a wide spectrum of biological processes. Epigenetic mechanisms control cellular morphology and function. Such regulatory mechanisms involve histone modifications, chromatin remodeling, DNA methylation, non-coding regulatory RNA molecules, and RNA modifications. One of the most well-studied epigenetic modifications is DNA methylation that plays key roles in development, health, and disease. Our brain is probably the most complex part of our body, with a high level of DNA methylation. A key protein that binds to different types of methylated DNA in the brain is the methyl-CpG binding protein 2 (MeCP2). MeCP2 acts in a dose-dependent manner and its abnormally high or low expression level, deregulation, and/or genetic mutations lead to neurodevelopmental disorders and aberrant brain function. Recently, some of MeCP2-associated neurodevelopmental disorders have emerged as neurometabolic disorders, suggesting a role for MeCP2 in brain metabolism. Of note, MECP2 loss-of-function mutation in Rett Syndrome is reported to cause impairment of glucose and cholesterol metabolism in human patients and/or mouse models of disease. The purpose of this review is to outline the metabolic abnormalities in MeCP2-associated neurodevelopmental disorders that currently have no available cure. We aim to provide an updated overview into the role of metabolic defects associated with MeCP2-mediated cellular function for consideration of future therapeutic strategies.

BIGKnock: fine-mapping gene-based associations via knockoff analysis of biobank-scale data

We propose BIGKnock (BIobank-scale Gene-based association test via Knockoffs), a computationally efficient gene-based testing approach for biobank-scale data, that leverages long-range chromatin interaction data, and performs conditional genome-wide testing via knockoffs. BIGKnock can prioritize causal genes over proxy associations at a locus. We apply BIGKnock to the UK Biobank data with 405,296 participants for multiple binary and quantitative traits, and show that relative to conventional gene-based tests, BIGKnock produces smaller sets of significant genes that contain the causal gene(s) with high probability. We further illustrate its ability to pinpoint potential causal genes at [Formula: see text] of the associated loci.

Integrated Whole-Exome and Transcriptome Sequencing Indicated Dysregulation of Cholesterol Metabolism in Eyelid Sebaceous Gland Carcinoma

Purpose

To identify the molecular background of eyelid sebaceous gland carcinomas (SCs), we conducted the integrated whole-exome sequencing and transcriptome sequencing for eyelid SCs in this study.

Methods

The genetic alterations were studied by whole-exome sequencing, and the messenger RNA expression was studied using Oxford Nanopore Technologies (ONT) in five paired fresh eyelid SC tissues and adjacent normal tissues. Integrated analysis of exome and transcriptomic information was conducted for filtering candidate driver genes. Protein-protein interaction (PPI) network of filtered candidate genes was analyzed by STRING. The protein expression was verified by immunohistochemistry in 29 eyelid SCs and 17 compared normal sebaceous gland tissues.

Results

The average numbers of pathogenic somatic single-nucleotide variants (SNVs) and indels in eyelid SCs were 75 and 28, respectively. Tumor protein p53 (TP53), zinc finger protein 750 (ZNF750), filaggrin 2 (FLG2), valosin-containing protein (VCP), and zinc finger protein 717 (ZNF717) were recurrent mutated genes. A mean of 844 differentially expressed genes (DEGs) were upregulated, and 1401 DEGs were downregulated in SC samples. The intersection of DEG-based pathways and mutation-based pathways was mainly involved in microbial infection and inflammation, immunodeficiency, cancer, lipid metabolism, and the other pathways. The intersection of DEGs and mutated genes consisted of 55 genes, of which 15 genes formed a PPI network with 4 clusters. The PPI cluster composed of scavenger receptor class B member 1 (SCARB1), peroxisome proliferator-activated receptor γ (PPARG), peroxisome proliferator-activated receptor γ coactivator 1α (PPARGC1A) was involved in cholesterol metabolism. The expression of SCARB1 protein was found to be increased, whereas that of PPARG protein was decreased in eyelid SCs compared to that in the normal sebaceous glands.

Conclusions

Increased SCARB1 and decreased PPARG indicated that dysregulation of cholesterol metabolism might be involved in carcinogenesis of eyelid SCs.

Translational Relevance

The malfunction in cholesterol metabolism might advance our knowledge of the carcinogenesis of eyelid SCs.

Recombinant GM-CSF for diseases of GM-CSF insufficiency: Correcting dysfunctional mononuclear phagocyte disorders

Introduction

Endogenous granulocyte-macrophage colony-stimulating factor (GM-CSF), identified by its ability to support differentiation of hematopoietic cells into several types of myeloid cells, is now known to support maturation and maintain the metabolic capacity of mononuclear phagocytes including monocytes, macrophages, and dendritic cells. These cells sense and attack potential pathogens, present antigens to adaptive immune cells, and recruit other immune cells. Recombinant human (rhu) GM-CSF (e.g., sargramostim [glycosylated, yeast-derived rhu GM-CSF]) has immune modulating properties and can restore the normal function of mononuclear phagocytes rendered dysfunctional by deficient or insufficient endogenous GM-CSF.

Methods

We reviewed the emerging biologic and cellular effects of GM-CSF. Experts in clinical disease areas caused by deficient or insufficient endogenous GM-CSF examined the role of GM-CSF in mononuclear phagocyte disorders including autoimmune pulmonary alveolar proteinosis (aPAP), diverse infections (including COVID-19), wound healing, and anti-cancer immune checkpoint inhibitor therapy.

Results

We discuss emerging data for GM-CSF biology including the positive effects on mitochondrial function and cell metabolism, augmentation of phagocytosis and efferocytosis, and immune cell modulation. We further address how giving exogenous rhu GM-CSF may control or treat mononuclear phagocyte dysfunction disorders caused or exacerbated by GM-CSF deficiency or insufficiency. We discuss how rhu GM-CSF may augment the anti-cancer effects of immune checkpoint inhibitor immunotherapy as well as ameliorate immune-related adverse events.

Discussion

We identify research gaps, opportunities, and the concept that rhu GM-CSF, by supporting and restoring the metabolic capacity and function of mononuclear phagocytes, can have significant therapeutic effects. rhu GM-CSF (e.g., sargramostim) might ameliorate multiple diseases of GM-CSF deficiency or insufficiency and address a high unmet medical need.

Benzotriazole ultraviolet stabilizer UV-234 promotes foam cell formation in RAW264.7 macrophages

Benzotriazole ultraviolet stabilizers (BUVSs) have been reported to induce inflammatory responses which may promote cholesterol accumulation and to downregulate the expression of genes involved in cholesterol biosynthesis; hence, we speculated whether BUVSs promote foam cell formation, which plays a key role in all stages of atherosclerosis. Herein, we used high-content imaging to screen all available BUVSs; of all the 17 candidates, 6 of them could promote foam cell formation at 10 μM. Further analyses showed that one BUVS UV-234 markedly increased the foam cell staining intensity by 15.0%-55.9% in the 0.5-10 μM exposure groups in a dose-dependent manner. Cholesterol influx was markedly enhanced by 21.0%-24.5% in the 5-10 μM exposure groups and cholesterol efflux was downregulated by 21.2%-59.3% in the 0.5-10 μM exposure groups, indicating that cholesterol efflux may play a major role in foam formation considering cholesterol efflux was downregulated at a relatively low concentration. Gene expression of ABCA1 and ABCG1 which regulate the cholesterol efflux were also decreased at 0.5-10 μM. The degradation of hypoxia-inducible factor 1α (HIF1α) via the ubiquitin-proteasome system was observed at 0.5-10 μM, probably contributing to the downregulated expression of the genes encoding liver X receptors (LXR) α/β and their targets, ABCA1 and ABCG1. Thus, our study revealed that BUVSs frequently detected in the environment can promote foam cell formation in macrophages, contributing to the risk of atherosclerosis in humans.

Combined targeting of fatty acid amide hydrolase and melatonin receptors promotes neuroprotection and stimulates inflammation resolution in rats

BACKGROUND AND PURPOSE

Devising novel strategies to therapeutically favour inflammation resolution and provide neuroprotection is an unmet clinical need. Enhancing endocannabinoid tone by inhibiting the catabolic enzyme fatty acid amide hydrolase (FAAH), or stimulating melatonin receptors has therapeutic potential to treat neuropathological states in which neuroinflammation plays a central role.

EXPERIMENTAL APPROACH

A rodent hippocampal explant model of inflammatory injury was used to assess the effects of UCM1341, a dual-acting compound with FAAH inhibitory action and agonist activity at melatonin receptors, against neuroinflammatory damage. FAAH activity was measured by a radiometric assay, and N-acylethanolamine levels were assessed by HPLC-MS/MS methods. FAAH distribution, evolution of inflammation and the contribution of UCM1341 to the expression of proteins controlling macrophage behaviour were investigated by biochemical and confocal analyses.

KEY RESULTS

UCM1341 exhibited greater neuroprotection against neuroinflammatory degeneration, compared with the reference compounds URB597 (FAAH inhibitor) and melatonin. During neuroinflammation, UCM1341 augmented the levels of anandamide and N-oleoylethanolamine, but not N-palmitoylethanolamine, up-regulated PPAR-α levels, attenuated demyelination and prevented the release of TNF-α. UCM1341 modulated inflammatory responses by contributing to microglia/macrophage polarization, stimulating formation of lipid-laden macrophages and regulating expression of proteins controlling cholesterol metabolism and efflux. The neuroprotective effects of UCM1341 were prevented by PPARα, TRPV1 and melatonin receptor antagonists.

CONCLUSION AND IMPLICATIONS

UCM1341, by enhancing endocannabinoid and melatoninergic signalling, benefits neuroprotection and stimulates inflammation resolution pathways. Our findings provide an encouraging prospect of therapeutically targeting endocannabinoid and melatoninergic systems in inflammatory demyelinating states in the CNS.