PPARγ signaling and emerging opportunities for improved therapeutics

Bisphenol AF induces lipid metabolism disorders, oxidative stress and upregulation of heat shock protein 70 in zebrafish

Bisphenol AF (BPAF) is a widespread endocrine disruptor in the environment, and the use of BPAF has been strongly associated with the development of several diseases. In this study, we investigated the effects of BPAF on growth, development, oxidative stress and lipid metabolism in zebrafish. We chose the concentrations based on the measured LC50 at 96 h post-fertilization (96 hpf), and the zebrafish embryos were exposed to three different concentrations (0.125, 0.5 and 2 μmol/L). The findings indicated that BPAF exposure in zebrafish leaded to alterations in heart rate, body length and hatching rate, as well as an accumulation of red blood cells in the heart. Additionally, BPAF exposure resulted in increased levels of neutrophils, reactive oxygen species (ROS) and malondialdehyde (MDA), and decreased activity of antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)), thus disturbing the balance between oxidative and antioxidative systems. BPAF promoted fatty acid catabolism and inhibited fatty acid synthesis, ultimately leading to a reduction in fatty acid content. Mechanistically, RNA-seq analysis and RT-qPCR revealed a significant upregulation of heat shock protein 70 (hsp70) after BPAF exposure. Inhibition of hsp70 with VER-155008 ameliorated BPAF-induced oxidative stress. These data provided a novel approach to investigate BPAF-induced oxidative stress and suggested that regulation of hsp70 is a crucial target for alleviating this process.

The therapeutic potential of Rosiglitazone in modulating scar formation through PPAR-γ pathway

The prevention and treatment of scars has always posed a challenge in the medical field. Researchers have reached the consensus that safe, effective and affordable treatments are needed. Here, by conducting non-targeted metabolomics and RNA sequencing experiments, we revealed that a significant number of metabolites and genes related to glucose and lipid metabolism underwent changes during scar formation, with peroxisome proliferator-activated receptor-γ (PPAR-γ) exerting a profound influence. Considering that rosiglitazone is a selective orally active PPAR-γ receptor agonist, scar models were induced in rats, and rosiglitazone was administered at different dosages. We characterized rosiglitazone as a crucial mediator in a rat scar model in vivo and in vitro in two models of transforming growth factor β1(TGF-β1) stimulated fibroblasts (NIH 3T3 and 3T3 L1). Functionally, activation of PPAR-γ with rosiglitazone effectively impedes fibrosis and mitigates scar formation. Rosiglitazone also inhibits some inflammatory factors, and downregulates triglyceride, lactic acid, glycogen and lactic dehydrogenase levels in rat scars. Conversely, rosiglitazone increases adenosine triphosphate (ATP) production and increases free fatty acid levels and the activity of acetyl-CoA carboxylase, fatty acid synthetase, succinate dehydrogenase. Collectively, these findings shed light on the underlying mechanisms and suggest that the use of rosiglitazone could be a promising therapeutic approach to alleviate fibrosis and reduce scar formation.

Astilbin from Smilax china L. remarkably inhibits LPS-induced endometritis in rats via blocking positive feedback between TLR4 and IL-6R signalling pathways in a PPAR-γ-dependent manner

ETHNOPHARMACOLOGICAL RELEVANCE

Astilbin (ATB), a natural flavonoid compound with anti-inflammatory bioactivities, can be isolated from Smilax china L., which has been used in traditional Chinese medicine to treat pelvic inflammatory disease (PID) (including endometritis). Our previous studies reported that flavonoids from Smilax china rhizome (FSCR) have therapeutic effects in rats with PID. However, the effects of ATB, the main active component of FSCR, against endometritis remain unknown.

AIM OF THE STUDY

We aim to investigate the role of ATB on endometritis induced by lipopolysaccharide (LPS) in rats and elucidate the mechanisms underlying anti-inflammatory action of ATB on LPS-stimulated endometrial epithelial cells (EECs).

METHODS

The effects and action mechanisms of ATB on LPS-induced endometritis in rats and LPS-induced EECs were systematically assessed using H&E staining, immunohistochemistry, ELISA, RT-PCR, western blotting, immunofluorescence, molecular docking and siRNA knockdown technology.

RESULTS

ATB significantly alleviated typical uterine pathological damages in endometritis, decreased inflammatory cytokine levels in both serum and uterus, and also inhibited the excessive release of inflammatory cytokines in EECs induced by LPS. Mechanistically, ATB markedly upregulated PPAR-γ levels and suppressed the overexpression of TLR4 and IL-6R proteins and their downstream signals, MyD88, and phosphorylation of NF-κB P65, JAK2, and STAT3, in vivo. Further, the effects of ATB on PPAR-γ protein expression, and NF-κB and STAT3 signalling activation in LPS-induced EECs were consistent with the results of in vivo experiments. Furthermore, both PPAR-γ-specific siRNA transfection and a selective PPAR-γ antagonist abolished ATB-induced inhibition of NF-κB and STAT3 signalling activation and production of inflammatory cytokines. Molecular docking and in vitro experiments further proved that ATB can target PPAR-γ binding.

CONCLUSION

Overall, our results demonstrated that ATB can significantly inhibit endometritis in rats, presumably through interfering with NF-κB and STAT3 signal transduction in a PPAR-γ-dependent manner, blocking the positive feedback between NF-κB and STAT3 signalling. Our findings provide new evidences for developing the ATB, the main compound identified from FSCR, as a potential therapeutic agent for endometritis.

Nuclear receptor PPARγ targets GPNMB to promote oligodendrocyte development and remyelination

Myelin injury occurs in brain ageing and in several neurological diseases. Failure of spontaneous remyelination is attributable to insufficient differentiation of oligodendrocyte precursor cells (OPCs) into mature myelin-forming oligodendrocytes in CNS demyelinated lesions. Emerging evidence suggests that peroxisome proliferator-activated receptor γ (PPARγ) is the master gatekeeper of CNS injury and repair and plays an important regulatory role in various neurodegenerative diseases. Although studies demonstrate positive effects of PPARγ in oligodendrocyte ontogeny in vitro, the cell-intrinsic role of PPARγ and the molecular mechanisms involved in the processes of OPC development and CNS remyelination in vivo are poorly understood. Here, we identify PPARγ as an enriched transcription factor in the dysfunctional OPCs accumulated in CNS demyelinated lesions. Its expression increases during OPC differentiation and myelination and is closely related to the process of CNS demyelination/remyelination. Administration of pharmacological agonists of PPARγ not only promotes OPC differentiation and CNS myelination, but also causes a significant increase in remyelination in both cuprizone- and lysophosphatidylcholine-induced demyelination models. In contrast, the attenuation of PPARγ function, either through the specific knockout of PPARγ in oligodendrocytes in vivo or through its inhibition in vitro, leads to decreased OPC maturation, hindered myelin generation and reduced therapeutic efficacy of PPARγ agonists. At a mechanistic level, PPARγ induces myelin repair by directly targeting glycoprotein non-metastatic melanoma protein B (GPNMB), a novel regulator that drives OPCs to differentiate into oligodendrocytes, promotes myelinogenesis in the developing CNS of postnatal mice and enhances remyelination in mice with lysophosphatidylcholine-induced demyelination. In conclusion, our evidence reveals that PPARγ is a positive regulator of endogenous OPC differentiation and CNS myelination/remyelination and suggests that PPARγ and/or its downstream sensor (GPNMB) might be a candidate pharmacological target for regenerative therapy in the CNS.

Differential changes in the microglial transcriptome between neonatal and adult mice after spinal cord injury

Spinal cord injury (SCI) remains a significant therapeutic challenge, lacking effective treatment options. Related studies have found that neonatal microglia are more effective than adult microglia in promoting the recovery of SCI, but the reason why neonatal, not adult, microglia are more conducive to SCI recovery is not clear, the differences of gene expression and pathways between them are still worth exploring. Therefore, we examined changes in the microglial transcriptome after SCI in neonatal and adult mice. We identified hub genes or pathways that exhibited significant differential expression between the two groups. Four Gene sets were established for further analysis, named Gene set 1, Gene set 2, Gene set 3, Gene set 4, respectively. GO analysis revealed enrichment in categories critical for injury repair, including DNA metabolism, replication, recombination, meiotic cell cycle progression, regulation of cell-cell adhesion, megakaryocyte and endothelial development, modulation of the neuroinflammatory response, endocytosis, and regulation of cytokine production and cell migration. KEGG analysis revealed enrichment in pathways critical for various cellular processes, including the p53, TNF, PI3K-AKT, PPAR and B cell receptor signaling pathway, axon guidance, cytokine-cytokine receptor interaction. PPI and TF-hub gene-microRNA networks were constructed to elucidate the underlying gene regulatory mechanisms. Additionally, drug prediction was performed to identify potential therapeutic candidates. Finally, 11 hub genes (Chek1, RRM2, Lyve1, Mboat1, Clec4a3, Ccnd1, Cdk6, Zeb1, Igf1, Pparg, and Cd163) were selected from four Gene sets for further validation using qRT-PCR. We identified candidate genes and pathways involved in microglial transcriptome heterogeneity after SCI in neonatal and adult mice. These findings provide valuable insights into potential therapeutic targets for neonatal microglia in the treatment of SCI.

F-box protein 22: A prognostic biomarker for colon cancer associated with immune infiltration and chemotherapy resistance

BACKGROUND

Colon cancer represents a significant malignant neoplasm within the digestive system, characterized by a high incidence rate and substantial disease burden. The F-box protein 22 (FBXO22) plays a role in forming a specific type of ubiquitin ligase subunit, which is expressed abnormally in various malignant neoplasms and shows a notable relationship with prognosis in patients with cancer. Nevertheless, the function of FBXO22 in the context of colon cancer remains inadequately elucidated.

AIM

To explore the role of FBXO22 in colon cancer by examining FBXO22 expression patterns and analyzing how the protein affects the prognosis in patients who have undergone surgery.

METHODS

Samples of cancerous and nearby normal tissues from patients with colon cancer were gathered, along with pertinent clinical data. Expression levels of the FBXO22 gene in both cancerous and paracancerous tissues were assessed through immunohistochemistry. The median H score served as a criterion for categorizing FBXO22 gene expression into high and low levels in cancerous tissues, and the relationship between these expression levels and various pathologic characteristics of patients, such as age, sex, and clinical stage, was analyzed. Colon cancer cell lines HCT116 and DLD-1 were used and divided into three groups: A blank control group, a negative control group, and a si-FBXO22 group. FBXO22 gene mRNA and protein expression were measured 24 hours post-transfection using real-time fluorescence quantitative polymerase chain reaction and western blotting. The proliferation capabilities of the cells in each group were assessed using the Cell Counting Kit-8 assay and 5-ethynyl-2'-deoxyuridine assay, while cellular migration and invasion abilities were evaluated using scratch healing and Transwell assays. Various online platforms, including the Timer Immune Estimation Resource, were used to analyze pan-cancer expression, promoter methylation levels, and mutation frequencies of the FBXO22 gene in colon cancer patients. Additionally, the correlation between FBXO22 gene expression, patient prognosis, immune cell infiltration, and the expression of immune molecules in the colon cancer microenvironment was investigated. The relationship between FBXO22 gene expression and chemotherapy resistance, along with the potential mechanisms of action of the FBXO22 gene, were analyzed using The Cancer Genome Atlas dataset and the Genomics of Drug Sensitivity in Cancer drug training set via R software.

RESULTS

Compared with normal colonic tissues, the FBXO22 gene was highly expressed in colon cancer tissues. Post-operative patients with colon cancer elevated FBXO22 reduced survival and exhibited resistance to various chemotherapeutic agents. FBXO22 expression suppresses the infiltration of anti-tumor immune cells. In vitro, FBXO22 knockdown inhibited the proliferation and migration of colon cancer cells.

CONCLUSION

The FBXO22 gene is a biomarker of poor prognosis in patients with colon cancer and has potential as a target for immunotherapy and overcoming chemotherapy resistance.

The Lian-Dou-Qing-Mai Formula activates the PPARγ-LXRα-ABCA1/ABCG1 pathway by regulating IL-10, leading to the promotion of cholesterol efflux and a reduction in atherosclerotic plaques

BACKGROUND

To observe the effect of the Lian-Dou-Qing-Mai (LDQM) formula on lipid metabolism in mice and explore its mechanism from the perspective of regulating the PPARγ/LXRα/ABCA1 signaling pathway.

METHODS

THP-1 cells were induced to transform into foam cells with ox-LDL. Atherosclerosis (AS) models were constructed using a high-fat diet in ApoE-/- mice. Detection kits were used to evaluate triglyceride (TG) and total cholesterol (TC) content; TNF-α, MCP-1, MMP-9, TMP-1, PPARγ, LXRα, ABCA1, and ABCG1 mRNA and protein expression were identified using real-time PCR and western blot. Aortic plaque development and lipid deposition were seen using hematoxylin and eosin (HE) and oil red O staining, respectively.

RESULTS

In the cell model, LDQM could inhibit the formation of THP-1 macrophage-derived foam cells and the expression of inflammatory factors, promote macrophage cholesterol efflux, increase the expression of IL-10, and activate the PPARγ-LXRα-ABCA1/ABCG1 pathway. Additional IL-10 treatment further promotes LDQM-induced cholesterol efflux in THP-1 cells; In vivo models, LDQM inhibited the area of atherosclerotic lesions, aortic lipid deposition, and inflammation levels in ApoE-/- mice through IL-10, and activated the expression level of the PPARγ-LXRα-ABCA1/ABCG1 pathway.

CONCLUSION

LDQM may affect the PPARγ/LXRα/ABCA1 signaling pathway through IL-10, regulate lipid metabolism, reduce serum inflammatory expression and lipid deposition, and improve the formation of atheroplaques.

The Role of the MAPK Signaling Pathway in Cardiovascular Disease: Pathophysiological Mechanisms and Clinical Therapy

Cardiovascular disease (CVD) is a serious global health issue with high mortality rates worldwide. Despite the numerous advancements in the study of CVD pathogenesis in recent years, further summarization and elaboration of specific molecular pathways are required. An extensive body of research has been conducted to elucidate the association between the MAPK signaling pathway, which is present in all eukaryotic organisms, and the pathogenesis of cardiovascular disease. This review aims to provide a comprehensive summary of the research conducted on MAPK and CVD over the past five years. The primary focus is on four specific diseases: heart failure, atherosclerosis, myocardial ischemia-reperfusion injury, and cardiac hypertrophy. The review will also address the pathophysiological mechanisms of MAPK in cardiovascular diseases, with the objective of proposing novel clinical treatment strategies for CVD.

Psoriasis Risk Is Lower in Type 2 Diabetes Patients Using Dipeptidyl Peptidase-4 Inhibitors or Thiazolidinediones Compared to Sulfonylureas

The risk of psoriasis in diabetic patients has rarely been explored. This study aims to compare the risk of incident psoriasis in patients with Type 2 diabetes (T2D) who initiate dipeptidyl peptidase-4 inhibitors (DPP-4is) or thiazolidinediones (TZDs) with those who initiate sulfonylureas, the most common second-line glucose-lowering therapy, in addition to metformin monotherapy. This sequential, propensity-score-matched, new-user comparative effectiveness study utilized a target trial emulation framework. It included adults with T2D receiving metformin monotherapy, using data from 2006 to 2015 from a general population database in Taiwan. The primary outcome was the incidence of psoriasis, determined through diagnoses recorded in urgent care, hospital, and outpatient department records. Cox proportional hazards and Poisson regressions with 1:4 propensity score matching was employed to evaluate the risk factors for psoriasis after adjusting for comorbidities and the use of other medications. In 49,810 propensity score-matched adults with T2D (27,630 men [55.4%]; mean age 57.5 years) identified in the database, the incidence rate of psoriasis in DPP-4i users was 188 cases per 100,000 person-years, lower than in sulfonylurea users (467 cases per 100,000 person-years), with a hazard ratio(HR) of 0.422 (95% CI, 0.273-0.716). For the TZD vs. sulfonylurea comparison, the HR was 0.35, but the smaller matched dataset resulted in wide confidence intervals. The findings suggest that the use of DPP-4is is associated with a lower risk of psoriasis compared to sulfonylureas in patients with T2D. These results can guide the selection of glucose-lowering therapies in T2D patients who are at risk of developing psoriasis.

PPARs in atherosclerosis: The spatial and temporal features from mechanism to druggable targets

BACKGROUND

Atherosclerosis is a chronic and complex disease caused by lipid disorder, inflammation, and other factors. It is closely related to cardiovascular diseases, the chief cause of death globally. Peroxisome proliferator-activated receptors (PPARs) are valuable anti-atherosclerosis targets that showcase multiple roles at different pathological stages of atherosclerosis and for cell types at different tissue sites.

AIM OF REVIEW

Considering the spatial and temporal characteristics of the pathological evolution of atherosclerosis, the roles and pharmacological and clinical studies of PPARs were summarized systematically and updated under different pathological stages and in different vascular cells of atherosclerosis. Moreover, selective PPAR modulators and PPAR-pan agonists can exert their synergistic effects meanwhile reducing the side effects, thereby providing novel insight into future drug development for precise spatial-temporal therapeutic strategy of anti-atherosclerosis targeting PPARs.

KEY SCIENTIFIC

Concepts of Review: Based on the spatial and temporal characteristics of atherosclerosis, we have proposed the importance of stage- and cell type-dependent precision therapy. Initially, PPARs improve endothelial cells' dysfunction by inhibiting inflammation and oxidative stress and then regulate macrophages' lipid metabolism and polarization to improve fatty streak. Finally, PPARs reduce fibrous cap formation by suppressing the proliferation and migration of vascular smooth muscle cells (VSMCs). Therefore, research on the cell type-specific mechanisms of PPARs can provide the foundation for space-time drug treatment. Moreover, pharmacological studies have demonstrated that several drugs or compounds can exert their effects by the activation of PPARs. Selective PPAR modulators (that specifically activate gene subsets of PPARs) can exert tissue and cell-specific effects. Furthermore, the dual- or pan-PPAR agonist could perform a better role in balancing efficacy and side effects. Therefore, research on cells/tissue-specific activation of PPARs and PPAR-pan agonists can provide the basis for precision therapy and drug development of PPARs.

Vasoactive intestinal peptide induces metabolic rewiring of human-derived cytotrophoblast cells to promote cell migration

The placenta has an extraordinary metabolic rate with high oxygen consumption. Extravillous cytotrophoblast cells (EVT) metabolism and function are critical to sustain their invasive phenotype supporting fetal development. Deficient EVT function underlies pregnancy complications as preeclampsia (PE) and fetal growth restriction (FGR). The vasoactive intestinal peptide (VIP) promotes human cytotrophoblast cell migration and invasion through mTOR signaling pathways suggesting its crucial role during placentation. Here we explored fatty acid uptake as well as lipid and glucose metabolism in human-derived cytotrophoblast cell function upon VIP stimulation. We found that VIP induced long chain fatty acid (LCFAs) uptake along with the expression of FATP2 transporter, CPT1 fatty acid oxidation (FAO)-rate limiting step importer, and lipid droplet accumulation. VIP induced the expression of glucose 6-P-dehydrogenase, a rate-limiting enzyme of the pentose phosphate pathway (PPP) and pyruvate dehydrogenase complex enzyme DLAT E2, without altering lactate secretion. This metabolic rewiring of trophoblast cells induced by VIP takes place without compromising mitochondrial function or reactive oxygen species (ROS) production. Moreover, cytotrophoblast cell migration induced by VIP required the three glycolysis, oxidative phosphorylation (OXPHOS) and FAO pathways. Our results provide evidence supporting VIP as a metabolic regulatory peptide in cytotrophoblast cells sustaining proper placentation and fetal growth.

Sex- and trimester-specific impact of gestational co-exposure to organophosphate esters and phthalates on insulin action among preschoolers: Findings from the Ma'anshan birth cohort

INTRODUCTION

Prenatal exposure to organophosphate esters (OPEs) and phthalic acid esters (PAEs) is ubiquitous among pregnant individuals. However, research exploring the relationship between prenatal co-exposure to OPEs and PAEs and childhood insulin function remains limited.

METHODS

In this study, utilizing data from 2,246 maternal-fetal dyads in the Ma'anshan Birth Cohort, associations between co-exposure to OPEs and PAEs and insulin action were analyzed. Repeated measures of tris (2-chloroethyl) phosphate, six OPE metabolites, and seven PAE metabolites were collected from maternal urine. Homeostasis model assessment of insulin resistance (HOMA-IR) and the insulin action index (IAI) served as outcome measures. After adjusting for potential confounders, the effects of repeated exposure on insulin action were evaluated using generalized estimating equations, while mixture effects were assessed through BayesianKernel Machine Regression and Quantile-Based G-Computation.

RESULTS

The average age of the children at the time of the study was 5.33 years. Repeated measures analysis revealed that prenatal exposure to MEP was positively associated with increased HOMA-IR (β, 0.027; 95 % CI: 0.002, 0.053), while IAI was inversely correlated with rising MEP levels (β, 0.025; 95 % CI: -0.046, -0.004) and MEHHP exposure (β, -0.128; 95 % CI: -0.218, -0.037). Mixed exposure modeling further indicated that co-exposure to OPEs and PAEs was positively linked to HOMA-IR (β, 0.058; 95 % CI: 0.001, 0.114) and negatively correlated with IAI (β, -0.054; 95 % CI: -0.097, -0.010), with stronger effects observed during the second trimester. Notably, the association was more pronounced in female children compared to males.

CONCLUSIONS

This study provides the first epidemiological evidence highlighting the pregnancy- and sex-specific links between prenatal co-exposure to OPEs and PAEs and childhood insulin action.

Identification of Novel Organo-Se BTSA-Based Derivatives as Potent, Reversible, and Selective PPARγ Covalent Modulators for Antidiabetic Drug Discovery

Recent studies have identified selective peroxisome proliferator-activated receptor γ (PPARγ) modulators, which synergistically engage in the inhibition mechanism of PPARγ-Ser273 phosphorylation, as a promising approach for developing safer and more effective antidiabetic drugs. Herein, we present the design, synthesis, and evaluation of a new class of organo-Se compounds, namely, benzothiaselenazole-1-oxides (BTSAs), acting as potent, reversible, and selective PPARγ covalent modulators. Notably, 2n, especially (R)-2n, displayed a high binding affinity and superior antidiabetic effects with diminished side effects. This is mainly because it can reversibly form a unique covalent bond with the Cys285 residue in PPARγ-LBD. Further mechanistic investigations revealed that it manifested such desired pharmacological profiles primarily by effectively suppressing PPARγ-Ser273 phosphorylation, enhancing glucose metabolism, and selectively upregulating the expression of insulin-sensitive genes. Collectively, our results suggest that (R)-2n holds promise as a lead compound for treating T2DM and also provides an innovative reversible covalent warhead reference for future covalent drug design.

Prognostic signature and therapeutic drug identification for dilated cardiomyopathy based on necroptosis via bioinformatics and experimental validation

Necroptosis, a type of programmed cell death, has been increasingly linked to cardiovascular disease development, yet its role in dilated cardiomyopathy (DCM) remains unclear. In this study, we analyzed the GSE5406 dataset from the GEO database to explore necroptosis-related prognostic signatures in DCM using LASSO regression. We identified five necroptosis-related genes (BID, CAMK2B, GLUL, HSP90AB1, CHMP5) that define a necroptosis-related signature with strong predictive value, evidenced by ROC curve areas of 0.852 and 0.957 in training and test sets, respectively. Our analyses, including GO and GSEA enrichment, focused on pathways associated with high necroptosis-related scores (NRS) and revealed significant immune cell infiltration. Notably, nTreg and iTreg cells were enriched in the high NRS group, while CD8 naive T cells and CD8 T cells positively correlated with NRS. Small molecule drugs fenofibrate, procyclidine, and tienilic acid emerged as potential therapeutic agents for high-risk patients, with fenofibrate showing efficacy in inhibiting DCM progression in an inflammatory animal model. These findings underscore the clinical relevance of necroptosis-related genes in assessing DCM progression and prognosis and highlight their potential for targeted therapeutic development.

Chronic glial activation and behavioral alterations induced by acute/subacute pioglitazone treatment in a mouse model of traumatic brain injury

Traumatic brain injury (TBI) is a disabling neurotraumatic condition and the leading cause of injury-related deaths and disability in the United States. Attenuation of neuroinflammation early after TBI is considered an important treatment target; however, while these inflammatory responses can induce secondary brain injury, they are also involved in the repair of the nervous system. Pioglitazone, which activates peroxisome proliferator-activated receptor gamma, has been shown to decrease inflammation acutely after TBI, but the long-term consequences of its use remain unknown. For this reason, the impacts of treatment with pioglitazone during the acute/subacute phase (30 min after injury and each subsequent 24 h for 5 days) after TBI were interrogated during the chronic phase (30- and 274-days post-injury (DPI)) in mice using the controlled cortical impact model of experimental TBI. Acute/subacute pioglitazone treatment after TBI results in long-term deleterious consequences, including disruption of tau homeostasis, chronic glial cell activation, neuronal pathology, and worsened injury severity particularly at 274 DPI, with male mice being more susceptible than female mice. Further, male pioglitazone-treated TBI mice exhibited increased dominant and offensive-like behavior while having a decreased non-social exploring behavior at 274 DPI. After TBI, both sexes exhibited glial activation at 30 DPI when treated with pioglitazone; however, while injury severity was increased in females it was not impacted in male mice. This work reveals that although pioglitazone has been shown to lead to attenuated TBI outcomes acutely, sex-based differences, timing and long-term consequences of treatment with glitazones must be considered and further studied prior to their clinical use for TBI therapy.

Damsin and neoambrosin: Two sesquiterpene lactones with affinity and different activity for PPAR and TRPA1 receptors

Ambrosia maritima L. (family Asteraceae) is an annual herb widely distributed throughout the Mediterranean region and Africa. The herb is employed in folk medicine for the treatment of many ailments. Herein, we report a comprehensive investigation of the diverse biological potential of two sesquiterpene lactones, damsin and neoambrosin, isolated from Ambrosia maritima. 1D and 2D NMR and HR-ESI-MS/MS were employed to characterize the chemical structures of both compounds. In order to identify biological targets of both compounds we investigated their potential affinity for peroxisome proliferator-activated receptors (PPARs) and transient receptor potential (TRP) channels, which are pleiotropic classes of receptors implicated in essential functions of the body. This was investigated using a luciferase assay and a calcium fluorometric assay. A carbonic anhydrase inhibition assay was also performed using stopped flow CO2 hydrase spectrophotometric assay. Our analysis revealed that unlike damsin, neoambrosin showed a selective partial agonist effect on PPARγ receptors and TRPA1 channels. Its binding mode was investigated through in silico analysis. Both compounds showed no affinity for the tested carbonic anhydrases. Overall, our study details the chemical properties of neoambrosin and damsin and highlights neoambrosin as novel, cost-effective partial agonist of PPARɣ and TRPA1 receptors despite additional in vivo studies are needed to elucidate its biological and pharmacological properties.

LRP1 mitigates intervertebral disc degeneration by inhibiting endoplasmic reticulum stress through stabilizing the PPARγ

Background

Intervertebral disc degeneration (IDD) is a significant cause of lower back pain, characterized by inflammation-mediated extracellular matrix (ECM) degradation, apoptosis, and aging of nucleus pulposus (NP) cells. Identifying key regulatory targets for these processes is crucial for IDD treatment. Previous research has highlighted the role of low-density lipoprotein receptor-related protein 1 (LRP1) in regulating ECM levels and cell fate, but its role in IDD remains under-explored. This study aims to elucidate the function and mechanism of LRP1 in the progression of IDD.

Methods

LRP1 expression was assessed in clinical tissue samples from patients diagnosed with IDD and in a rat IDD model established using needle puncture injuries. The effects of LRP1 knockdown and treatment with the LRP1 activator SP16 on apoptosis and ECM metabolism in NP cells were analyzed, with a focus on their relationship with endoplasmic reticulum (ER) stress. The interaction and regulatory mechanism between LRP1 and peroxisome proliferator-activated receptor gamma (PPARγ) were further explored to clarify how LRP1 regulates ER stress. Finally, the in vivo therapeutic effect of SP16 was investigated using a rat tail IDD model.

Results

We found that LRP1 expression was significantly downregulated in IDD. In NP cells with LRP1 knockdown, there was a marked increase in apoptosis and detrimental ECM remodeling, which were associated with the activation of ER stress. Our research further revealed that LRP1 interacts with PPARγ, stabilizing the PPARγ protein and preventing its lysosomal degradation, thereby mitigating ER stress. Activation of LRP1 in our models significantly reduced ER stress, matrix degradation, and apoptosis, thereby attenuating IDD both in vitro and in vivo.

Conclusion

This study systematically investigated the role and mechanisms of the LRP1/PPARγ/ER stress signaling axis in IDD. Our findings suggest that targeting LRP1 to modulate this signaling pathway could provide a promising therapeutic approach for the treatment of IDD.

The Translational potential of this Article

Our study demonstrated that LRP1 can reduce apoptosis and ECM degradation by inhibiting ER stress through stabilizing PPARγ, indicating that targeting LRP1 may be a novel therapeutic strategy for IDD.

Genomic Effects of Biomechanical Loading in Adolescent Human Growth Plate Cartilage: A Pilot Study

OBJECTIVE

The genomic effects of biomechanical loading on human growth plate cartilage are unknown so far. To address this, we used rare human growth plate biopsies obtained from children undergoing epiphysiodesis and exposed them to precisely controlled mechanical loading using a microloading device. The biopsies were cultured 24 hours after mechanical loading, followed by RNA-sequencing analyses to decipher the genomic regulation.

DESIGN

We conducted RNA-seq analysis of human growth plate cartilage obtained from three patients cultured ex vivo and subjected to cyclical mechanical loading with peak 0.4 N with frequency 0.77 Hz during a 30-second duration, using a specialized microloading device.

RESULTS

Gene ontology analysis revealed novel data showing three significantly upregulated signaling pathways, including notch, oxytocin, and tight junction, and three significantly downregulated signaling pathways, including lysosome, sphingolipid metabolism, and peroxisome proliferator-activated receptor (PPAR) in human growth plate cartilage. Moreover, we found 15 significantly regulated genes within these signaling pathways from all three patients. These genes included PSEN2, HEY1, and NCOR2 from the notch signaling; CACNB1 and PPP3R2 from the oxytocin signaling; ACTR3C, WHAMM, and ARHGEF18 from the tight junction signaling; ARSA, SMPD1, and CD68 from the lysosome signaling; ARSA and SMPD1 from the sphingolipid metabolism signaling; and SLC27A4 and AQP7 from the PPAR signaling pathway. In addition, 20 significantly upregulated genes and six significantly downregulated genes shared between two patient samples were identified.

CONCLUSION

Our study provides the first-ever transcriptomic data of mechanical loading of human growth plate cartilage. These findings can potentially provide genetic targets for future investigations in physiological and pathological bone growth conditions.

RNA-seq analysis and in vivo experiments identified the protective effect of kaempferol on idiopathic pulmonary fibrosis by regulating the PPARG/TNC signaling pathway to reduce ECM deposition

Idiopathic pulmonary fibrosis (IPF) is a chronic age-related lung disease with a high mortality rate. Kaempferol (KMP), an active ingredient in common plants and foods with anti-inflammatory, antioxidant and immunomodulatory properties, has been shown to be effective against fibrotic diseases. However, the molecular mechanisms underlying the treatment of IPF with KMP remain unclear. Therefore, IPF mice were established by intratracheal instillation of bleomycin (BLM) to explore the efficacy and underlying mechanism of KMP in the treatment of IPF. We found that KMP improved the body weight changes of BLM-induced IPF mice, alleviated inflammatory infiltration and collagen deposition, and decreased the expression levels of hydroxyproline, α-SMA, Col3a1, Mmp2, Timp1, Vim, Fn, TNF-α, TGF-β1, IL-6 and IL-8, while up-regulating the expression E-cadherin in lung tissues. The transcriptomic results showed that KMP may exert therapeutic effects against IPF by regulating the PPARG/TNC signaling pathway to reduce extracellular matrix (ECM) deposition. Interestingly, ROC curve analysis suggested that TNC and PPARG had good diagnostic performance for IPF, and TF prediction revealed that PPARG is an important upstream gene regulating TNC, and the IF experiment confirmed the co-localization of TNC and PPARG. Molecular docking showed that KMP bound well to PPARG and TNC, and IF results revealed that KMP significantly reduced the interaction between PPARG and TNC. Furthermore, RT-PCR, WB, IHC and IF experiments confirmed that KMP elevated the expression of PPARG and inhibited the expression of TNC, thus inhibiting the ECM-receptor interaction pathway and ultimately serving as a therapeutic treatment for IPF mice. These findings revealed that KMP reduced inflammatory infiltration and collagen deposition in the lungs of IPF mice and that the PPARG/TNC signaling pathway may be an important mechanism for the treatment of IPF with KMP, which provides a new perspective for the development of therapeutic approaches for IPF.

In vitro hair growth-promoting effects of araliadiol via the p38/PPAR-γ signaling pathway in human hair follicle stem cells and dermal papilla cells

Background

Scalp hair plays a crucial role in social communication by expressing personal appearance and self-identity. Consequently, hair loss often leads to a perception of unattractiveness, negatively impacting an individual's life and mental health. Currently, the use of Food and Drug Administration (FDA)-approved drugs for hair loss is associated with several side effects, highlighting the need for identifying new drug candidates, such as plant-derived phytochemicals, to overcome these issues.

Objective

This study investigated the hair growth-promoting effects of araliadiol, a polyacetylene compound found in plants such as Centella asiatica.

Methods

We employed an in vitro model comprising human hair follicle stem cells (HHFSCs) and human dermal papilla cells (HDPCs) to evaluate the hair growth-promoting effects of araliadiol. The proliferation-stimulating effects of araliadiol were assessed using water-soluble tetrazolium salt assay, adenosine triphosphate content assay, and crystal violet staining assay. In addition, we performed luciferase reporter assay, polymerase chain reaction analysis, cell fractionation, Western blot analysis, and enzyme-linked immunosorbent assay (ELISA) to elucidate the mechanism underlying the hair growth-inductive effects of araliadiol.

Results

Araliadiol exhibited both proliferation- and hair growth-promoting effects in HHFSCs and HDPCs. Specifically, it increased the protein expression of cyclin B1 and Ki67. In HHFSCs, it elevated the expression of hair growth-promoting factors, including CD34, vascular endothelial growth factor (VEGF), and angiopoietin-like 4. Similarly, araliadiol increased the expression of hair growth-inductive proteins such as fibroblast growth factor 7, VEGF, noggin, and insulin-like growth factor 1 in HDPCs. Subsequent Western blot analysis and ELISA using inhibitors such as GW9662 and SB202190 confirmed that these hair growth-promoting effects were dependent on the p38/PPAR-γ signaling in both HHFSCs and HDPCs.

Conclusion

Araliadiol promotes hair growth through the p38/PPAR-γ signaling pathway in human hair follicle cells. Therefore, araliadiol can be considered a novel drug candidate for the treatment of alopecia.

Non-Sugar Sweetener Rubusoside Alleviates Lipid Metabolism Disorder In Vivo and In Vitro by Targeting PPARγ/α, Lgals3, and Mknk2

Rubusoside─a high-sweetened, nonsugar sweetener─is mainly extracted from Rubus chingii var. suavissimus (S. Lee) L. T. Lu or Rubus suavissimus S. Lee (Chinese sweet leaf tea). We previously reported that rubusoside regulates lipid metabolism disorder in Syrian golden hamsters on a high-fat diet (HFD). This study aimed to reveal the underlying mechanisms through which rubusoside alleviates lipid metabolism disorder in vivo and in vitro. First, we analyzed the therapeutic properties of rubusoside in alleviating HFD-induced lipid metabolism disorder in C57BL/6J mice. Then, we analyzed the adipogenic effect of rubusoside in normal and Lgals3/Mknk2-overexpressing 3T3-L1 cells by exploring the mechanisms on peroxisome proliferator-activated receptor-γ/α (PPARγ/α), galectin-3 (Lgals3), mitogen-activated protein kinase interacting serine/threonine kinase-2 (Mknk2), p38 mitogen-activated protein kinase (p38MAPK), and extracellular regulated protein kinases 1/2 (ERK1/2) with RT-qPCR and Western blot. Our results showed a rubusoside-mediated reduction of HFD-induced weight gain, dyslipidemia, and decelerated hepatic steatosis and adipose tissue expansion in mice as well as improved adipogenesis in 3T3-L1 cells. Mechanistically, rubusoside up-regulated the PPARγ/α expression while down-regulating Lgals3 and Mknk2 expression in vivo and in vitro. Furthermore, rubusoside attenuated the adipogenic activity of PPARγ through increasing its site-specific phosphorylation mediated by p38MAPK and ERK1/2. Taken together, our findings suggest that rubusoside alleviates lipid metabolism disorder through multiple pathways and thus holds potential for future development.

Exploring PPAR Gamma and PPAR Alpha's Regulation Role in Metabolism via Epigenetics Mechanism

Peroxisome proliferator-activated receptors (PPARs) belong to a family of nuclear receptors. To date, three types of PPARs, namely PPARα, PPARδ, and PPARγ, have been identified, demonstrating co-expression across numerous tissues. PPARγ is primarily distributed in adipose tissue, the colon, the immune system, and the retina, while PPARα is predominantly expressed in metabolic tissues such as brown adipose tissue, the liver, and the kidneys. Both PPARγ and PPARα play crucial roles in various cellular processes. Recent data suggest that the PPAR family, among other mechanisms, might also be regulated by epigenetic mechanisms. Our recent studies, alongside numerous others, have highlighted the pivotal roles of DNA methylation and histone modifications in the regulation of PPARγ and PPARα, implicating them in the deterioration of metabolic disorders via epigenetic mechanisms. This still not fully understood mechanism of regulation in the nuclear receptors family has been summarized and described in the present paper. The present review summarizes the available data on PPARγ and PPARα regulation via epigenetic mechanisms, elucidating the link between the development of metabolic disorders and the dysregulation of PPARγ and PPARα resulting from these mechanisms.

Anti-adipogenesis and anti-obesity potential of alliin mediated by modulating glycolipid metabolism via activating PPARγ signaling

Garlic exhibits hypolipidemic, hypoglycemic, and cardiovascular benefits. The inconsistent results of garlic preparations on adipogenesis have caused more confusion in the public and academia. The compounds responsible for the anti-adipogenesis effect of garlic remain unknown. The present study aimed to verify the real anti-adipogenesis and anti-obesity component in garlic and explored its possible effects in metabolic syndrome. We verified the real anti-adipogenesis and anti-obesity components of garlic in 3T3-L1 preadipocytes and a 10-week-high fat diet (HFD)-induced obese mice. In vitro, two water-soluble and four typical lipid-soluble compounds of garlic were tested for their anti-adipogenesis. Then, the water-soluble compound, alliin, and two processing methods produced garlic oils, were evaluated in vivo study. Mice received oral administration of alliin (25 mg/kg) and garlic oils (15 mg/kg) daily for 8 weeks. Serum lipids, parameters of obesity, and indicators involved in regulating glycolipid metabolism were examined. Our findings confirmed that both water-soluble and lipid-soluble organosulfur compounds of garlic contributed to garlic's anti-adipogenesis effect, in which water-soluble sulfides, especially alliin, exhibited greater potency. Alliin possessed potent effects of anti-obesity and improvement in glucose and lipid metabolism in HFD-induced obese mice. Alliin mediated these effects partly attributed to its modulation of enzymatic activities within glycolipid metabolism and activating PPARγ signaling pathway. In contrast to odorous lipid-soluble sulfides, alliin is odorless, stable, and safe, and is an ideal nutraceutical or even medicinal candidates for the treatment of metabolic diseases. Alliin could be used to standardize the quality of garlic products.

Molecular mechanisms underlying methotrexate-induced intestinal injury and protective strategies

Methotrexate (MTX) is a folic acid reductase inhibitor that manages various malignancies as well as immune-mediated inflammatory chronic diseases. Despite being frequently prescribed, MTX's severe multiple toxicities can occasionally limit its therapeutic potential. Intestinal toxicity is a severe adverse effect associated with the administration of MTX, and patients are significantly burdened by MTX-provoked intestinal mucositis. However, the mechanism of such intestinal toxicity is not entirely understood, mechanistic studies demonstrated oxidative stress and inflammatory reactions as key factors that lead to the development of MTX-induced intestinal injury. Besides, MTX causes intestinal cells to express pro-inflammatory cytokines like interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), which activate nuclear factor-kappa B (NF-κB). This is followed by the activation of the Janus kinase/signal transducer and activator of the transcription3 (JAK/STAT3) signaling pathway. Moreover, because of its dual anti-inflammatory and antioxidative properties, nuclear factor erythroid-2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) has been considered a critical signaling pathway that counteracts oxidative stress in MTX-induced intestinal injury. Several agents have potential protective effects in counteracting MTX-provoked intestinal injury such as omega-3 polyunsaturated fatty acids, taurine, umbelliferone, vinpocetine, perindopril, rutin, hesperidin, lycopene, quercetin, apocynin, lactobacillus, berberine, zinc, and nifuroxazide. This review aims to summarize the potential redox molecular mechanisms of MTX-induced intestinal injury and how they can be alleviated. In conclusion, studying these molecular pathways might open the way for early alleviation of the intestinal damage and the development of various agent plans to attenuate MTX-mediated intestinal injury.

Procyanidin B2 improves developmental capacity of bovine oocytes via promoting PPARγ/UCP1-mediated uncoupling lipid catabolism during in vitro maturation

Metabolic balance is essential for oocyte maturation and acquisition of developmental capacity. Suboptimal conditions of in vitro cultures would lead to lipid accumulation and finally result in disrupted oocyte metabolism. However, the effect and mechanism underlying lipid catabolism in oocyte development remain elusive currently. In the present study, we observed enhanced developmental capacity in Procyanidin B2 (PCB2) treated oocytes during in vitro maturation. Meanwhile, reduced oxidative stress and declined apoptosis were found in oocytes after PCB2 treatment. Further studies confirmed that oocytes treated with PCB2 preferred to lipids catabolism, leading to a notable decrease in lipid accumulation. Subsequent analyses revealed that mitochondrial uncoupling was involved in lipid catabolism, and suppression of uncoupling protein 1 (UCP1) would abrogate the elevated lipid consumption mediated by PCB2. Notably, we identified peroxisome proliferator-activated receptor gamma (PPARγ) as a potential target of PCB2 by docking analysis. Subsequent mechanistic studies revealed that PCB2 improved oocyte development capacity and attenuated oxidative stress by activating PPARγ mediated mitochondrial uncoupling. Our findings identify that PCB2 intricately improves oocyte development capacity through targeted activation of the PPARγ/UCP1 pathway, fostering uncoupling lipid catabolism while concurrently mitigating oxidative stress.

Nuclear factor erythroid 2-related factor-mediated signaling alleviates ferroptosis during cerebral ischemia-reperfusion injury

Cardiac arrest (CA) is a significant challenge for emergency physicians worldwide and leads to increased morbidity and mortality rates. The poor prognosis of CA primarily stems from the complexity and irreversibility of cerebral ischemia-reperfusion injury (CIRI). Ferroptosis, a form of programmed cell death characterized by iron overload and lipid peroxidation, plays a crucial role in the progression and treatment of CIRI. In this review, we highlight the mechanisms of ferroptosis within the context of CIRI, focusing on its role as a key contributor to neuronal damage and dysfunction post-CA. We explore the crucial involvement of the nuclear factor erythroid 2-related factor (Nrf2)-mediated signaling pathway in modulating ferroptosis-associated processes during CIRI. Through comprehensive analysis of the regulatory role of Nrf2 in the cellular responses to oxidative stress, we highlight its potential as a therapeutic target for mitigating ferroptotic cell death and improving the neurological prognosis of patients experiencing CA. Furthermore, we discuss interventions targeting the Kelch-like ECH-associated protein 1/Nrf2/antioxidant response element pathway, including the use of traditional Chinese medicine and Western medicine, which demonstrate potential for attenuating ferroptosis and preserving neuronal function in CIRI. Owing to the limitations in the safety, specificity, and effectiveness of Nrf2-targeted drugs, as well as the technical difficulties and ethical constraints in obtaining the results related to the brain pathological examination of patients, most of the studies focusing on Nrf2-related regulation of ferroptosis in CIRI are still in the basic research stage. Overall, this review aims to provide a comprehensive understanding of the mechanisms underlying ferroptosis in CIRI, offering insights into novel therapeutics aimed at enhancing the clinical outcomes of patients with CA.

Unveiling the protective potential of mirabegron against thioacetamide-induced hepatic encephalopathy in rats: Insights into cAMP/PPAR-γ/p-ERK1/2/p S536 NF-κB p 65 and p-CREB/BDNF/TrkB in parallel with oxidative and apoptotic trajectories

Hepatic encephalopathy (HE) is one of the most prevalent and severe hepatic and brain disorders in which escalation of the oxidative, inflammatory and apoptotic trajectories pathologically connects acute liver injury with neurological impairment. Mirabegron (Mira) is a beta3 adrenergic receptor agonist with proven antioxidant and anti-inflammatory activities. The current research pointed to exploring Mira's hepato-and neuroprotective impacts against thioacetamide (TAA)-induced HE in rats. Rats were distributed into three experimental groups: the normal control group, the TAA group, received TAA (200 mg/kg/day for three consecutive days) and the Mira-treated group received Mira (10 mg/kg/day; oral gavage) for 15 consecutive days and intoxicated with TAA from the 13th to the 15th day of the experimental period. Mira counteracted hyperammonemia, enhanced rats' locomotor capability and motor coordination. It attenuated hepatic/neurological injuries by its antioxidant, anti-apoptotic as well as anti-inflammatory potentials. Mira predominantly targeted cyclic adenosine monophosphate (cAMP)/phosphorylated extracellular signal-regulated kinase (p-Erk1/2)/peroxisome proliferator-activated receptor gamma (PPARγ) dependent pathways via downregulation of p S536-nuclear factor kappa B p65 (p S536 NF-κB p 65)/tumor necrosis alpha (TNF-α) axis. Meanwhile, it attenuated nuclear factor erythroid 2-related factor (Nrf2) depletion in parallel with restoring of the neuroprotective defensive pathway by upregulation of cerebral cAMP/PPAR-γ/p-ERK1/2 and p-CREB/BDNF/TrkB besides reduction of GFAP immunoreactivity. Mira showed anti-apoptotic activity through inhibition of Bax immunoreactivity and elevation of Bcl2. To summarize, Mira exhibited a hepato-and neuroprotective effect against TAA-induced HE in rats via shielding antioxidant defense and mitigation of the pathological inflammatory and apoptotic axis besides upregulation of neuroprotective signaling pathways.

Gut microbiota-derived acetic acids promoted sepsis-induced acute respiratory distress syndrome by delaying neutrophil apoptosis through FABP4

In patients with sepsis, neutrophil apoptosis tends to be inversely proportional to the severity of sepsis, but its mechanism is not yet clear. This study aimed to explore the mechanism of fatty acid binding protein 4 (FABP4) regulating neutrophil apoptosis through combined analysis of gut microbiota and short-chain fatty acids (SCFAs) metabolism. First, neutrophils from bronchoalveolar lavage fluid (BALF) of patients with sepsis-induced acute respiratory distress syndrome (ARDS) were purified and isolated RNA was applied for sequencing. Then, the cecal ligation and puncture (CLP) method was applied to induce the mouse sepsis model. After intervention with differential SCFAs sodium acetate, neutrophil apoptosis and FABP4 expression were further analyzed. Then, FABP4 inhibitor BMS309403 was used to treat neutrophils. We found CLP group had increased lung injury score, lung tissue wet/dry ratio, lung vascular permeability, and inflammatory factors IL-1β, TNF-α, IL-6, IFN-γ, and CCL3 levels in both bronchoalveolar lavage fluid and lung tissue. Additionally, FABP4 was lower in neutrophils of ARDS patients and mice. Meanwhile, CLP-induced dysbiosis of gut microbiota and changes in SCFAs levels were observed. Further verification showed that acetic acids reduced neutrophil apoptosis and FABP4 expression via FFAR2. Besides, FABP4 affected neutrophil apoptosis through endoplasmic reticulum (ER) stress, and neutrophil depletion alleviated the promotion of ARDS development by BMS309403. Moreover, FABP4 in neutrophils regulated the injury of RLE-6TN through inflammatory factors. In conclusion, FABP4 affected by gut microbiota-derived SCFAs delayed neutrophil apoptosis through ER stress, leading to increased inflammatory factors mediating lung epithelial cell damage.

H3K9me3 demethylation by JMJD2B is regulated by pirfenidone resulting in improved NASH

NASH is characterized by hepatic lipid accumulation and inflammation; and JMJD2B-a histone demethylase-upregulation has been linked to its progression. Pirfenidone (PFD) is an antifibrotic agent with anti-inflammatory and antioxidant effects recognized to decrease NASH symptoms. Herein, our aim was to investigate PFD-induced epigenetics mechanisms involving JMJD2B and histone modifications in experimental NASH. Male C57BL/6J mice were fed with normo-diet, or high fat/carbohydrate diet (HF) for 16 weeks. A HF-subgroup was treated with PFD 300 mg/kg/d from week 8th to the end of protocol. Insulin tolerance test and liver and fat histological and biochemical analyses were carried out. Hepatic transcriptome was examined. Liver proteins were studied by western blot (WB) and Chromatin immunoprecipitation. In vitro, lipotoxicity was induced in HepG2 cells and proteins were evaluated using WB. Molecular docking was used to explore binding of PFD to JMJD2B. Mice treated with PFD reduced weight gain, epididymal fat and inflammatory nodules, and steatosis in liver tissue, as well as, improved biochemical test. PFD modified the expression of Jmjd2b, Pparg, Fasn and Srebp1, and restored JMJD2B protein and H3K9me3 repressive mark, both in animal and cell models. PFD increased hepatic enrichment of H3K9me2 and H3K9me3 at the promoter region of Fasn and Srebp1, and Pparg. In HepG2 cells, PFD reduced lipid vacuole accumulation. In silico, PFD interacted with JMJD2B catalytic site. PFD is an epigenetic regulator modifying JMJD2B activity, resulting in reduced NASH traits.

Structure-based screening, optimization and biological evaluation of novel chrysin-based derivatives as selective PPARγ modulators for the treatment of T2DM and hepatic steatosis

In consideration of several serious side effects induced by the classical AF-2 involved "lock" mechanism, recently disclosed PPARγ-Ser273 phosphorylation mode of action has become an alternative and mainstream mechanism for currently PPARγ-based drug discovery and development with an improved therapeutic index. In this study, by virtue of structure-based virtual high throughput screening (SB-VHTS), structurally chemical optimization by targeting the inhibition of the PPARγ-Ser273 phosphorylation as well as in vitro biological evaluation, which led to the final identification of a chrysin-based potential hit (YGT-31) as a novel selective PPARγ modulator with potent binding affinity and partial agonism. Further in vivo evaluation demonstrated that YGT-31 possessed potent glucose-lowering and relieved hepatic steatosis effects without involving the TZD-associated side effects. Mechanistically, YGT-31 presented such desired therapeutic index, mainly because it effectively inhibited the CDK5-mediated PPARγ-Ser273 phosphorylation, selectively elevated the level of insulin sensitivity-related Glut4 and adiponectin but decreased the expression of insulin-resistance-associated genes PTP1B and SOCS3 as well as inflammation-linked genes IL-6, IL-1β and TNFα. Finally, the molecular docking study was also conducted to uncover an interesting hydrogen-bonding network of YGT-31 with PPARγ-Ser273 phosphorylation-related key residues Ser342 and Glu343, which not only gave a clear verification for our targeting modification but also provided a proof of concept for the abovementioned molecular mechanism.

Synthesis and in vitro cytotoxicity of benzoxazole-based PPARα/γ antagonists in colorectal cancer cell lines

A series of benzoxazole-based amides and sulfonamides were synthesized and evaluated for their human peroxisome proliferator-activated receptor (PPAR)α and PPARγ activity. All tested compounds showed a dual antagonist profile on both PPAR subtypes; based on transactivation results, seven compounds were selected to test their in vitro antiproliferative activity in a panel of eight cancer cell lines with different expression rates of PPARα and PPARγ. 3f was identified as the most cytotoxic compound, with higher potency in the colorectal cancer cell lines HT-29 and HCT116. Compound 3f induced a concentration-dependent activation of caspases and cell-cycle arrest in both colorectal cancer models. Docking experiments were also performed to shed light on the putative binding mode of this novel class of dual PPARα/γ antagonists.

Low GPR81 in ER+ breast cancer cells drives tamoxifen resistance through inducing PPARα-mediated fatty acid oxidation

AIMS

The intricate molecular mechanisms underlying estrogen receptor-positive (ER+) breast carcinogenesis and resistance to endocrine therapy remain elusive. In this study, we elucidate the pivotal role of GPR81, a G protein-coupled receptor, in ER+ breast cancer (BC) by demonstrating low expression of GPR81 in tamoxifen (TAM)-resistant ER+ BC cell lines and tumor samples, along with the underlying molecular mechanisms.

MAIN METHODS

Fatty acid oxidation (FAO) levels and lipid accumulation were explored using MDA and FAβO assay, BODIPY 493/503 staining, and Lipid TOX staining. Autophagy levels were assayed using CYTO-ID detection and Western blotting. The impact of GPR81 on TAM resistance in BC was investigated through CCK8 assay, colony formation assay and a xenograft mice model.

RESULTS

Aberrantly low GPR81 expression in TAM-resistant BC cells disrupts the Rap1 pathway, leading to the upregulation of PPARα and CPT1. This elevation in PPARα/CPT1 enhances FAO, impedes lipid accumulation and lipid droplet (LD) formation, and subsequently inhibits cell autophagy, ultimately promoting TAM-resistant BC cell growth. Moreover, targeting GPR81 and FAO emerges as a promising therapeutic strategy, as the GPR81 agonist and the CPT1 inhibitor etomoxir effectively inhibit ER+ BC cell and tumor growth in vivo, re-sensitizing TAM-resistant ER+ cells to TAM treatment.

CONCLUSION

Our data highlight the critical and functionally significant role of GPR81 in promoting ER+ breast tumorigenesis and resistance to endocrine therapy. GPR81 and FAO levels show potential as diagnostic biomarkers and therapeutic targets in clinical settings for TAM-resistant ER+ BC.

Nutritional supplementation of breeding hens may promote embryonic development through the growth hormone-insulin like growth factor axis

The late stage of embryo development is a crucial period of metabolic changes, with rapid organ development requiring a substantial supply of nutrients. During this phase, maternal nutritional levels play a vital role in the growth, development, and metabolism of the offspring. In this study, we added 2 doses of β-carotene (βc) (120 mg/kg and 240 mg/kg) to the daily diet of Hailan Brown laying hens to investigate the impact of maternal nutritional enrichment on embryo development. Maternal nutrition supplementation significantly increased the expression of chicken embryo liver index, growth hormone (GH), insulin-like growth factor-1 (IGF-1), and hepatocyte growth factor (HGF) in serum. At the same time, the expression of GH/growth hormone receptor (GHR), IGF-1 mRNA, and Proliferating Cell Nuclear Antigen (PCNA) protein in the liver was upregulated, indicating that maternal nutrition intervention may promote chicken embryo liver development through the GH-IGF-1 axis. Transcriptome sequencing results showed that differential genes in liver after maternal nutritional supplementation with β-carotene were enriched in pathways related to cell proliferation and metabolism. Consequently, we postulated that maternal β-carotene supplementation might operate via the GH-IGF-1 axis to regulate the expression of genes involved in growth and development, thereby promoting liver development. These results contribute to formulating more effective poultry feeding strategies to promote offspring growth and development.

Synthetic Biomimetic Liposomes Harness Efferocytosis Machinery for Highly Efficient Macrophages-Targeted Drug Delivery to Alleviate Inflammation

Macrophages play pivotal roles in the regulation of inflammatory responses and tissue repair, making them a prime target for inflammation alleviation. However, the accurate and efficient macrophages targeting is still a challenging task. Motivated by the efficient and specific removal of apoptotic cells by macrophages efferocytosis, a novel biomimetic liposomal system called Effero-RLP (Efferocytosis-mediated Red blood cell hybrid Liposomes) is developed which incorporates the membrane of apoptotic red blood cells (RBCs) with liposomes for the purpose of highly efficient macrophages targeting. Rosiglitazone (ROSI), a PPARγ agonist known to attenuate macrophage inflammatory responses, is encapsulated into Effero-RLP as model drug to regulate macrophage functions in DSS-induced colitis mouse model. Intriguingly, the Effero-RLP exhibits selective and efficient uptake by macrophages, which is significantly inhibited by the efferocytosis blocker Annexin V. In animal models, the Effero-RLP demonstrates rapid recognition by macrophages, leading to enhanced accumulation at inflammatory sites. Furthermore, ROSI-loaded Effero-RLP effectively alleviates inflammation and protects colon tissue from injury in the colitis mouse model, which is abolished by deletion of macrophages from mice model. In conclusion, the study highlights the potential of macrophage targeting using efferocytosis biomimetic liposomes. The development of Effero-RLP presents novel and promising strategies for alleviating inflammation.

Tumor cell-intrinsic MELK enhanced CCL2-dependent immunosuppression to exacerbate hepatocarcinogenesis and confer resistance of HCC to radiotherapy

BACKGROUND

The outcome of hepatocellular carcinoma (HCC) is limited by its complex molecular characteristics and changeable tumor microenvironment (TME). Here we focused on elucidating the functional consequences of Maternal embryonic leucine zipper kinase (MELK) in the tumorigenesis, progression and metastasis of HCC, and exploring the effect of MELK on immune cell regulation in the TME, meanwhile clarifying the corresponding signaling networks.

METHODS

Bioinformatic analysis was used to validate the prognostic value of MELK for HCC. Murine xenograft assays and HCC lung metastasis mouse model confirmed the role of MELK in tumorigenesis and metastasis in HCC. Luciferase assays, RNA sequencing, immunopurification-mass spectrometry (IP-MS) and coimmunoprecipitation (CoIP) were applied to explore the upstream regulators, downstream essential molecules and corresponding mechanisms of MELK in HCC.

RESULTS

We confirmed MELK to be a reliable prognostic factor of HCC and identified MELK as an effective candidate in facilitating the tumorigenesis, progression, and metastasis of HCC; the effects of MELK depended on the targeted regulation of the upstream factor miR-505-3p and interaction with STAT3, which induced STAT3 phosphorylation and increased the expression of its target gene CCL2 in HCC. In addition, we confirmed that tumor cell-intrinsic MELK inhibition is beneficial in stimulating M1 macrophage polarization, hindering M2 macrophage polarization and inducing CD8 + T-cell recruitment, which are dependent on the alteration of CCL2 expression. Importantly, MELK inhibition amplified RT-related immune effects, thereby synergizing with RT to exert substantial antitumor effects. OTS167, an inhibitor of MELK, was also proven to effectively impair the growth and progression of HCC and exert a superior antitumor effect in combination with radiotherapy (RT).

CONCLUSIONS

Altogether, our findings highlight the functional role of MELK as a promising target in molecular therapy and in the combination of RT therapy to improve antitumor effect for HCC.

The association between vitamin D and the progression of diabetic nephropathy: insights into potential mechanisms

Aims

Vitamin D deficiency (VDD) is prevalent in the population, with inadequate intake, impaired absorption and metabolism as the main causative factors. VDD increases the risk of developing chronic diseases such as type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN), but the molecular mechanisms underlying this phenomenon are not known. The aim of this study was to investigate the association and potential mechanisms of vitamin D levels with the progression of DN by analyzing general clinical data and using bioinformatics methods.

Methods

The study included 567 diabetes mellitus type 2 (T2DM) patients from the Rocket Force Characteristic Medical Center as the case group and 221 healthy examinees as the normal control group. T2DM patients were categorized into T2DM, early diabetic nephropathy (EDN), and advanced diabetic nephropathy (ADN) based on the progression of diabetic nephropathy. The renal RNA-seq and scRNA-seq data of patients with DN were mined from public databases, and the differential expression of vitamin D-related genes in normal-EDN-ADN was analyzed by bioinformatics method, protein interaction network was constructed, immune infiltration was evaluated, single cell map was drawn, and potential mechanisms of VD and DN interaction were explored.

Results

Chi-square test showed that vitamin D level was significantly negatively correlated with DN progression (p < 0.001). Bioinformatics showed that the expression of vitamin D-related cytochrome P450 family genes was down-regulated, and TLR4 and other related inflammatory genes were abnormally up-regulated with the progression of DN. Vitamin D metabolism disturbance up-regulate "Nf-Kappa B signaling pathway," B cell receptor signaling pathway and other immune regulation and insulin resistance related pathways, and inhibit a variety of metabolic pathways. In addition, vitamin D metabolism disturbance are strongly associated with the development of diabetic cardiomyopathy and several neurological disease complications.

Conclusion

VDD or vitamin D metabolism disturbance is positively associated with the severity of renal injury. The mechanisms may involve abnormal regulation of the immune system by vitamin D metabolism disturbance, metabolic suppression, upregulation of insulin resistance and inflammatory signalling pathways.

New Insights into the Role of PPARγ in Skin Physiopathology

Peroxisome proliferator-activated receptor gamma (PPARγ) is a transcription factor expressed in many tissues, including skin, where it is essential for maintaining skin barrier permeability, regulating cell proliferation/differentiation, and modulating antioxidant and inflammatory responses upon ligand binding. Therefore, PPARγ activation has important implications for skin homeostasis. Over the past 20 years, with increasing interest in the role of PPARs in skin physiopathology, considerable effort has been devoted to the development of PPARγ ligands as a therapeutic option for skin inflammatory disorders. In addition, PPARγ also regulates sebocyte differentiation and lipid production, making it a potential target for inflammatory sebaceous disorders such as acne. A large number of studies suggest that PPARγ also acts as a skin tumor suppressor in both melanoma and non-melanoma skin cancers, but its role in tumorigenesis remains controversial. In this review, we have summarized the current state of research into the role of PPARγ in skin health and disease and how this may provide a starting point for the development of more potent and selective PPARγ ligands with a low toxicity profile, thereby reducing unwanted side effects.

Role of Nrf2/HO-1, PPAR-γ, and cytoglobin signals in the pathogenesis of methotrexate-induced testicular intoxication in rats and the protective effect of diacerein

Methotrexate (MTX) is an inhibitor of folic acid reductase used in managing a variety of malignancies. Testicular injury by MTX is one of its serious adverse effects. The current investigation aims to assess the protective effects of diacerein (DIA) on testicular injury by MTX and clarify the possible underlying mechanisms. Testicular injury in rats was induced by a single injection of 20 mg/kg body weight of MTX. DIA was given in 25 mg/kg body weight/day and 50 mg/kg body weight/day doses for 10 days. Compared to the MTX group, DIA attenuated testicular intoxication as evidenced by improvement of testicular histopathological abnormalities and increased serum testosterone and luteinizing hormone. DIA attenuated testicular oxidative stress changes by lowering testicular MDA and boosting GSH content and SOD activity. Moreover, administration of DIA attenuated MTX-induced testicular inflammation, as proved by decreased TNF-α and IL-6. At the molecular level, DIA induced significant upregulation in Nrf2, HO-1, PPAR-γ, and cytoglobin protein expression. The present results proved that DIA, in a dose-dependent manner, exhibited notable amelioration of testicular toxicity induced by MTX through augmentation of anti-inflammatory and antioxidant effects combined by upregulating Nrf2/HO-1, PPAR-γ, and cytoglobin signaling.

The combination of berberine and isoliquiritigenin synergistically improved adipose inflammation and obesity-induced insulin resistance

White adipose tissue accumulation and inflammation contribute to obesity by inducing insulin resistance. Herein, we aimed to screen the synergistic components of the herbal pair Coptidis Rhizoma-Glycyrrhizae Radix et Rhizoma for the treatment of insulin resistance and explore the potential synergistic mechanisms. Enzyme-linked immunosorbent assay and quantitative PCR were used to detect expression levels of inflammatory genes in vitro and in vivo. Western blotting and immunohistochemistry were performed to detect protein levels of the insulin signaling pathway and macrophage markers. The effects on obesity-induced insulin resistance were verified using a diet-induced obesity (DIO) mouse model. Interactions between macrophage and adipocyte were assessed using a cellular supernatant transfer assay. Berberine (BBR) and isoliquiritigenin (ISL) alleviated mRNA levels and secretion of inflammatory genes in vitro and in vivo. Furthermore, BBR acted synergistically with ISL to ameliorate obesity and dyslipidemia in DIO mice. Meanwhile, the combination treatment significantly improved glucose intolerance and insulin resistance and decreased M1-macrophage accumulation and infiltration in the adipose tissue. Mechanistically, co-treatment with BBR and ISL upregulated the protein expression of the IRS1-PI3K-Akt insulin signaling pathway, enhanced glucose uptake in adipocyte, and suppressed the interaction between macrophage and adipocyte. BBR and ISL were identified as the synergistic components of the herbal pair Coptidis Rhizoma-Glycyrrhizae Radix et Rhizoma for treating insulin resistance. The synergistic combination of BBR with ISL can be a promising and effective strategy for improving obesity-induced adipose inflammation and insulin resistance.

Whole transcriptome mapping reveals the lncRNA regulatory network of TFP5 treatment in diabetic nephropathy

BACKGROUND

TFP5 is a Cdk5 inhibitor peptide, which could restore insulin production. However, the role of TFP5 in diabetic nephropathy (DN) is still unclear.

OBJECTIVE

This study aims to characterize the transcriptome profiles of mRNA and lncRNA in TFP5-treated DN mice to mine key lncRNAs associated with TFP5 efficacy.

METHODS

We evaluated the role of TFP5 in DN pathology and performed RNA sequencing in C57BL/6J control mice, C57BL/6J db/db model mice, and TFP5 treatment C57BL/6J db/db model mice. The differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) were analyzed. WGCNA was used to screen hub-gene of TFP5 in treatment of DN.

RESULTS

Our results showed that TFP5 therapy ameliorated renal tubular injury in DN mice. In addition, compared with the control group, the expression profile of lncRNAs in the model group was significantly disordered, while TFP5 alleviated the abnormal expression of lncRNAs. A total of 67 DElncRNAs shared among the three groups, 39 DElncRNAs showed a trend of increasing in the DN group and decreasing after TFP treatment, while the remaining 28 showed the opposite trend. DElncRNAs were enriched in glycosphingolipid biosynthesis signaling pathways, NF-κB signaling pathways, and complement activation signaling pathways. There were 1028 up-regulated and 1117 down-regulated DEmRNAs in the model group compared to control group, and 123 up-regulated and 153 down-regulated DEmRNAs in the TFP5 group compared to the model group. The DEmRNAs were involved in PPAR and MAPK signaling pathway. We confirmed that MSTRG.28304.1 is a key DElncRNA for TFP5 treatment of DN. TFP5 ameliorated DN maybe by inhibiting MSTRG.28304.1 through regulating the insulin resistance and PPAR signaling pathway. The qRT-PCR results confirmed the reliability of the sequencing data through verifying the expression of ENSMUST00000211209, MSTRG.31814.5, MSTRG.28304.1, and MSTRG.45642.14.

CONCLUSION

Overall, the present study provides novel insights into molecular mechanisms of TFP5 treatment in DN.

Recent advances and structure-activity relationship studies of DPP-4 inhibitors as anti-diabetic agents

Diabetes mellitus (DM) is one of the largest public health problems worldwide and in the last decades various therapeutic targets have been investigated. For the treatment of type-2 DM (T2DM), dipeptidyl peptidase-4 (DPP-4) is one of the well reported target and has established safety in terms of cardiovascular complexicity. Preclinical and clinical studies using DPP-4 inhibitors have demonstrated its safety and effectiveness and have lesser risk of associated hypoglycaemic effect making it suitable for elderly patients. FDA has approved a number of structurally diverse DPP-4 inhibitors for clinical use. The present manuscript aims to focus on the well reported hybrid and non-hybrid analogues and their structural activity relationship (SAR) studies. It aims to provide structural insights for this class of compounds pertaining to favourable applicability of selective DPP-4 inhibitors in the treatment of T2DM.

Stratification and prognostic evaluation of breast cancer subtypes defined by obesity-associated genes

OBJECTIVE

Breast cancer was the most common type of cancer among women worldwide, significantly impacting their quality of life and survival rates. And obesity has been widely accepted as an important risk factor for breast cancer. However, the specific mechanisms by which obesity affects breast cancer were still unclear. Therefore, studying the impact mechanisms of obesity as a risk factor for breast cancer was of utmost importance.

METHODS

This study was based on TCGA breast cancer RNA transcriptomic data and the GeneCard obesity gene set. Through single and multiple factor Cox analysis and LASSO coefficient screening, seven hub genes were identified. The independent mechanisms of these seven hub genes were evaluated from various aspects, including survival data, genetic mutation data, single-cell sequencing data, and immune cell data. Additionally, the risk prognosis model and the neural network diagnostic model were established to further investigate these seven hub genes. In order to achieve precision treatment for breast cancer (BRCA), based on the RNA transcriptomic data of the seven genes, 1226 BRCA patients were divided into two subtypes: BRCA subtype 1 and BRCA subtype 2. By studying and comparing the immune microenvironment, investigating the mechanisms of differential gene expression, and exploring the mechanisms of subnetworks, we aim to explore the clinical differences in the presentation of BRCA subtypes and achieve precision treatment for BRCA. Finally, qRT-PCR experiments were conducted to validate the conclusions of the bioinformatics analysis.

RESULTS

The 7 hub genes showed good diagnostic independence and can serve as excellent biomarkers for molecular diagnosis. However, they do not perform well as independent prognostic molecular markers for BRCA patients. When predicting the survival of BRCA patients, their AUC values at 1 year, 3 years, and 5 years are mostly below 0.5. Nevertheless, through the establishment of the risk prognosis model considering the combined effect of the seven hub genes, it was found that the survival prediction of BRCA patients can be significantly improved. The risk prognosis model, compared to the independent use of the seven hub genes as prognostic markers, achieved higher timeROC AUC values at 1 year, 3 years, and 5 years, with values of 0.651, 0.669, and 0.641 respectively. Additionally, the neural network diagnostic model constructed from the 7 genes performs well in diagnosing BRCA, with an AUC value of 0.94, accurately identifying BRCA patients. The two subtypes identified by the seven hub genes exhibited significant differences in survival period, with subtype 1 having a poor prognosis. The differential mechanisms between the two subtypes mainly originate from regulatory differences in the immune microenvironment. Finally, the results of this study's bioinformatics analysis were validated through qRT-PCR experiments.

CONCLUSION

7 hub genes serve as excellent independent biomarkers for molecular diagnosis, and the neural network diagnostic model can accurately distinguish BRCA patients. In addition, based on the expression levels of these seven genes in BRCA patients, two subtypes can be reliably identified: BRCA subtype 1 and BRCA subtype 2, and these two subtypes showed significant differences in BRCA patient survival prognosis, proportion of immune cells, and expression levels of immune cells. Among them, patients with subtype 1 of BRCA had a poor prognosis.

Raloxifene-driven benzothiophene derivatives: Discovery, structural refinement, and biological evaluation as potent PPARγ modulators based on drug repurposing

By virtue of the drug repurposing strategy, the anti-osteoporosis drug raloxifene was identified as a novel PPARγ ligand through structure-based virtual high throughput screening (SB-VHTS) of FDA-approved drugs and TR-FRET competitive binding assay. Subsequent structural refinement of raloxifene led to the synthesis of a benzothiophene derivative, YGL-12. This compound exhibited potent PPARγ modulation with partial agonism, uniquely promoting adiponectin expression and inhibiting PPARγ Ser273 phosphorylation by CDK5 without inducing the expression of adipongenesis associated genes, including PPARγ, aP2, CD36, FASN and C/EBPα. This specific activity profile resulted in effective hypoglycemic properties, avoiding major TZD-related adverse effects like weight gain and hepatomegaly, which were demonstrated in db/db mice. Molecular docking studies showed that YGL-12 established additional hydrogen bonds with Ile281 and enhanced hydrogen-bond interaction with Ser289 as well as PPARγ Ser273 phosphorylation-related residues Ser342 and Glu343. These findings suggested YGL-12 as a promising T2DM therapeutic candidate, thereby providing a molecular framework for the development of novel PPARγ modulators with an enhanced therapeutic index.

Regulation of lipid metabolism by E3 ubiquitin ligases in lipid-associated metabolic diseases

Previous studies have progressively elucidated the involvement of E3 ubiquitin (Ub) ligases in regulating lipid metabolism. Ubiquitination, facilitated by E3 Ub ligases, modifies critical enzymes in lipid metabolism, enabling them to respond to specific signals. In this review, we aim to present a comprehensive analysis of the role of E3 Ub ligases in lipid metabolism, which includes lipid synthesis and lipolysis, and their influence on cellular lipid homeostasis through the modulation of lipid uptake and efflux. Furthermore, it explores how the ubiquitination process governs the degradation or activation of pivotal enzymes, thereby regulating lipid metabolism at the transcriptional level. Perturbations in lipid metabolism have been implicated in various diseases, including hepatic lipid metabolism disorders, atherosclerosis, diabetes, and cancer. Therefore, this review focuses on the association between E3 Ub ligases and lipid metabolism in lipid-related diseases, highlighting enzymes critically involved in lipid synthesis and catabolism, transcriptional regulators, lipid uptake translocators, and transporters. Overall, this review aims to identify gaps in current knowledge, highlight areas requiring further research, offer potential targeted therapeutic approaches, and provide a comprehensive outlook on clinical conditions associated with lipid metabolic diseases.

Effects of different combinations of koumine and gelsemine on growth performance, intestinal health, and transcriptome of Cyprinus carpio

Koumine (KM) and gelsemine (GS) have shown significant benefits in livestock production, but their potential in aquaculture remains largely unexplored. This study examined the impact of different KM and GS combinations as feed additives on C. carpio (90 fish per group, initial weight 1.95 ± 0.08 g). KM and GS were introduced in ratios of 2:2 (mg/kg), 2:1 (mg/kg), and 2:0.67 (mg/kg) over a 10-week aquaculture experiment. The results demonstrate that the 2:1 (mg/kg) group increases the villus length, muscular layer thickness, crude protein, and crude fat content. Regarding fatty acid content, KM and GS enhance the levels of various fatty acids, including the total saturated fatty acid and total monounsaturated fatty acid. Additionally, KM and GS improve the composition and function of the intestinal microbiota. The 2:1 (mg/kg) group significantly elevates the enzymatic activities of SOD, MDA, CAT and upregulates the expression of immune-related genes such as toll-like receptor 2, transforming growth factor β, and glutathione S-transferase. Transcriptomic analysis suggests that KM and GS may have potential benefits for nutrient utilization and immune regulation in C. carpio. In summary, this study provides valuable insights into the use of KM and GS as feed additives in aquaculture.

Sesamin and sesamolin potentially inhibit adipogenesis through downregulating the peroxisome proliferator-activated receptor γ protein expression and activity in 3T3-L1 cells

Sesamin and sesamolin are major sesame lignans that have demonstrated anti-inflammatory, anticancer, and neuroprotective properties and potential benefits in the liver, cardiovascular diseases, and metabolic syndrome. However, despite previous research on their antiobesity effects and underlying mechanisms, a comprehensive investigation of these aspects is still lacking. In this study, we evaluated the regulatory effects of 20 to 80 µM sesamin and sesamolin on adipogenesis in vitro using 3T3-L1 cells as a model cell line. We hypothesized that the lignans would inhibit adipogenic differentiation in 3T3-L1 cells through the regulation of peroxisome proliferator-activated receptor γ (PPARγ). Our data indicate that sesamin and sesamolin inhibited the adipogenic differentiation of 3T3-L1 cells by dose-dependently decreasing lipid accumulation and triglyceride formation. Sesamin and sesamolin reduced the mRNA and protein expression of the adipogenesis-related transcription factors, PPARγ and CCAAT/enhancer-binding protein α, leading to the dose-dependent downregulations of their downstream targets, fatty acid binding protein 4, hormone-sensitive lipase, lipoprotein lipase, and glucose transporter 4. In addition, glucose uptake was dose-dependently attenuated by sesamin and sesamolin in both differentiated 3T3-L1 cells and HepG2 cells. Interestingly, our results suggested that sesamin and sesamolin might directly bind to PPARγ to inhibit its transcriptional activity. Finally, sesamin and sesamolin decreased the phosphorylation of 3 mitogen-activated protein kinase signaling components in differentiated 3T3-L1 cells. Taken together, our findings suggest that sesamin and sesamolin may exhibit antiobesity effects by potentially downregulating PPARγ and its downstream genes through the mitogen-activated protein kinase signaling pathway, offering important insights into the molecular mechanisms underlying the potential antiobesity effects of sesamin and sesamolin.

Hepatocyte miR-21-5p-deficiency alleviates APAP-induced liver injury by inducing PPARγ and autophagy

Acetaminophen (APAP)-induced liver injury is one of the most frequent causes of acute liver failure worldwide. Significant increases in the levels of miRNA-21 in both liver tissues and plasma have been observed in APAP-overdosed animals and humans. However, the mechanistic effect of miRNA-21 on acute liver injury remains unknown. In this study, we generated a new hepatocyte-specific miRNA-21 knockout (miR-21-HKO) mouse line. miR-21-HKO and the background-matched sibling wild-type (WT) mice were treated with a toxic dose of APAP. Compared with WT mice, miR-21 HKO mice showed an increased survival, a reduction of necrotic hepatocytes, and an increased expression of light chain 3 beta, which suggested an autophagy activation. The expression of PPARγ was highly induced in the livers of miR-21-HKO mice after a 2-h APAP treatment, which preceded the activation of LC3B at the 12 h APAP treatment. miR-21 negatively regulated PPARγ protein expression by targeting its 3'-UTR. When PPARγ function was blocked by a potent antagonist GW9662 in miR-21-HKO mice, the autophage activation was significantly diminished, suggesting an indispensable role of PPARγ signaling pathway in miR-21-mediated hepatotoxicity. Taken together, hepatocyte-specific depletion of miRNA-21 alleviated APAP-induced hepatotoxicity by activating PPARγ and autophagy, demonstrating a crucial new regulatory role of miR-21 in APAP-mediated liver injury.

PPAR γ activation in chondrocytes alleviates glucocorticoid-induced oxidative stress, mitochondrial impairment, and pyroptosis via autophagic flow enhancement

Osteoarthritis (OA) is a progressive age-related disease characterised by pathological changes in the synovium, articular cartilage, and subchondral bone, significantly reducing the patients' quality of life. This study investigated the role of glucocorticoids, specifically dexamethasone, in OA progression, with a particular focus on their effects on chondrocytes. Although glucocorticoids are commonly used for OA pain relief, our research demonstrated that high concentrations of dexamethasone may accelerate OA progression by enhancing the ability of reactive oxygen species to inhibit chondrocyte autophagy, resulting in cell death and accelerated cartilage degeneration. Despite reports on the acceleration of pathogenesis and cartilage damage in some patients of OA taking corticosteroids, the mechanism behind the same has not been investigated. This necessitates an investigation of the concentration-dependent changes in the cartilage cells upon dexamethasone administration. In addition, the protective effect of PPAR γ on chondrocytes can prevent the decrease in chondrocyte autophagy and delay cartilage degeneration. Therefore, our study suggests that the therapeutic use of glucocorticoids in OA treatment should be more nuanced considering their potential detrimental effects. Future investigations should focus on the mechanisms underlying the glucocorticoid-mediated modulation of cell death processes, which could provide insights into new therapeutic strategies for OA treatment.

Multispecies transcriptomics identifies SIKE as a MAPK repressor that prevents NASH progression

Nonalcoholic fatty liver (NAFL) remains relatively benign, but high-risk to end-stage liver diseases become highly prevalent when it progresses into nonalcoholic steatohepatitis (NASH). Our current understanding of the development of NAFL to NASH remains insufficient. In this study, we revealed MAP kinase (MAPK) activation as the most notable molecular signature associated with NASH progression across multiple species. Furthermore, we identified suppressor of IKKε (SIKE) as a conserved and potent negative controller of MAPK activation. Hepatocyte-specific overexpression of Sike prevented NASH progression in diet- and toxin-induced mouse NASH models. Mechanistically, SIKE directly interacted with TGF-β-activated kinase 1 (TAK1) and TAK1-binding protein 2 (TAB2) to interrupt their binding and subsequent TAK1-MAPK signaling activation. We found that indobufen markedly up-regulated SIKE expression and effectively improved NASH features in mice and macaques. These findings identify SIKE as a MAPK suppressor that prevents NASH progression and provide proof-of-concept evidence for targeting the SIKE-TAK1 axis as a potential NASH therapy.

Downregulation of the CD151 protects the cardiac function by the crosstalk between the endothelial cells and cardiomyocytes via exosomes

BACKGROUND

Heart failure (HF) is the last stage in the progression of various cardiovascular diseases. Although it is documented that CD151 contributes to regulate the myocardial infarction, the function of CD151 on HF and involved mechanisms are still unclear.

METHOD AND RESULTS

In the present study, we found that the recombinant adeno-associated virus (rAAV)-mediated endothelial cell-specific knockdown of CD151-transfected mice improved transverse aortic constriction (TAC)-induced cardiac function, attenuated myocardial hypertrophy and fibrosis, and increased coronary perfusion, whereas overexpression of the CD151 protein aggravated cardiac dysfunction and showed the opposite effects. In vitro, the cardiomyocytes hypertrophy induced by PE were significantly improved, while the proliferation and migration of cardiac fibroblasts (CFs) were significantly reduced, when co-cultured with the CD151-silenced endothelial cells (ECs). To further explore the mechanisms, the exosomes from the CD151-silenced ECs were taken by cardiomyocyte (CMs) and CFs, verified the intercellular communication. And the protective effects of CD151-silenced ECs were inhibited when exosome inhibitor (GW4869) was added. Additionally, a quantitative proteomics method was used to identify potential proteins in CD151-silenced EC exosomes. We found that the suppression of CD151 could regulate the PPAR signaling pathway via exosomes.

CONCLUSION

Our observations suggest that the downregulation of CD151 is an important positive regulator of cardiac function of heart failure, which can regulate exosome-stored proteins to play a role in the cellular interaction on the CMs and CFs. Modulating the exosome levels of ECs by reducing CD151 expression may offer novel therapeutic strategies and targets for HF treatment.