Sex- and depot-specific differences in cellular insulin responsiveness during adipose expansion

BACKGROUND

Adipose tissue distribution, metabolism, and expansion capacity exhibit notable sex- and depot-specific differences. Herein, we monitored adipocyte traits related to insulin responsiveness and glucose transport during adipose expansion in visceral and subcutaneous fat from male and female mice.

MATERIALS AND METHODS

Adipocytes were isolated from perigonadal and inguinal adipose tissue of chow-fed female and male C57Bl6/J mice and assessed for adipocyte size distribution using a coulter counter; glucose uptake and cytosolic volume were measured using glucose tracer assays. GLUT1, GLUT4, and IRS-1 protein levels were assessed by western blot. Pharmacological inhibition (BAY876) of GLUT1 and GLUT4 was used to resolve their respective contribution to cellular glucose transport.

KEY FINDINGS

Independent of adiposity or sex, visceral adipocytes were larger and displayed higher glucose transport, cytosolic volume, and GLUT4 levelsthan subcutaneous adipocytes. GLUT1 content was higher in subcutaneous than visceral adipocytes in both sexes. Pharmacological inhibition confirmed that GLUT1 contributes to <10 % of adipocyte glucose uptake, while GLUT4 facilitates most of both basal and insulin-stimulated glucose uptake. Females showed significantly higher basal and insulin-stimulated glucose transport, higher cytosolic volume, and greater GLUT4 and IRS-1 protein levels than males in both adipose depots. Interestingly, insulin responsiveness was preserved in female subcutaneous adipocytes but deteriorated in subcutaneous male adipocytes during adipose expansion.

SIGNIFICANCE

The improved insulin responsiveness, increased glucose transport, and higher levels of GLUT4 and IRS-1 in adipocytes might protect females from the adverse systemic effects linked to obesity. Insulin responsiveness was preserved in female subcutaneous adipocytes during adipose tissue expansion, which could contribute to the reduced risk of females to develop systemic insulin resistance.

crRNA array-mediated CRISPR/Cas12a coupling with dual RPA for highly sensitive detection of Streptomyces aureofaciens Tü117 from hypertension with multi-signal output

Accurate and sensitive detection of Streptomyces aureofaciens Tü117 is crucial for hypertension classification and early warning. To achieve this, a dual recombinase polymerase amplification coupled with a crRNA array-mediated CRISPR/Cas12a assay (DR-CAMCas) was developed, enabling multi-signal output for precise identification and detection of S. aureofaciens Tü117. The 16S rDNA and LipReg4 genes of S. aureofaciens Tü117 are amplified simultaneously via one-step dual RPA, activating the crRNA array-mediated CRISPR/Cas12a system to cleave exogenous FQ-reporters, releasing fluorescent signals. DR-CAMCas offers high amplification efficiency, multi-site recognition through crRNA array signal superposition, and the programmability of CRISPR/Cas12a, achieving ultrasensitive detection with a linear range of 10 to 108 cfu/mL and a limit of detection of approximately 3 cfu/mL. DR-CAMCas successfully detected S. aureofaciens Tü117 in fecal samples from high-salt diet-induced hypertensive mice and hypertensive patients, matching qPCR results and demonstrating high reliability and practicality. Additionally, target-induced cleavage of a DNA linker by DR-CAMCas dispersed AuNPs-DNA probes, enabling colorimetric detection. Integrated onto lateral flow sensors, DR-CAMCas allows point-of-care testing via simple visual strip analysis. Its triple signal output meets diverse detection needs, offering a promising tool for diagnosing salt-sensitive hypertension.

The role of LECT2 in kidney fibrosis progression and endoplasmic reticulum stress

AIMS

Our previous studies showed that Leukocyte Cell-Derived Chemotaxin 2 (LECT2), as a ligand for Tie1, modulates vascular endothelial cell function, promoting hepatic fibrosis. These findings prompted an investigation into whether LECT2 effects kidney fibrosis. This study aimed to elucidate the role of LECT2 in kidney fibrosis and its regulation of C/EBP homologous protein (CHOP) expression.

MATERIALS AND METHODS

We utilized Lect2-KO mice, Lect2-2 A-Cre-Rosa26-LSL-tdTomato reporter mice, and EA.hy926 cells overexpressing LECT2 to establish models of kidney fibrosis and endoplasmic reticulum stress (ERS). The expression characteristics of LECT2 in fibrotic kidneys, its effects on CHOP expression, and the mechanisms by which LECT2 modulates kidney fibrosis were systematically investigated.

KEY FINDINGS

Lect2 expression was upregulated in clinical fibrotic kidney samples and mouse models of fibrotic kidneys. Lect2-KO mice demonstrated reduced fibrosis and less impairment of kidney function in a kidney fibrosis model. In Lect2-KO mice, expression of the ERS marker CHOP was increased, and vascular endothelial cells were activated to express CHOP earlier, reducing kidney function damage. Overexpression of LECT2 decreased apoptosis, promoted cell survival, and upregulated the expression of profibrotic factors through activation of the EGFR/AKT/PI3K pathway. Lect2 deficiency in fibrotic kidneys led to attenuated myofibroblast activation and reduced collagen deposition.

SIGNIFICANCE

The absence of LECT2 alleviates kidney fibrosis by inhibiting the EGFR/PI3K/AKT pathway, activating ERS, promoting partial endothelial cell apoptosis, and reducing the secretion of profibrotic factors. LECT2 emerges as a promising therapeutic target for kidney fibrosis, and its inhibition offers a potential strategy for CKD treatment.

Electrochemical bienzymatic biosensor for pyruvate kinase activity evaluation and inhibitor screening

This study describes the development of a pyruvate kinase (PyK)-biosensor for the evaluation of PyK activity, as a diagnostic tool for early cancer screening and detection of kinase inhibitors used in cancer treatment, with the evaluation of the inhibition mechanism. The biosensor was constructed by co-immobilizing the enzymes PyK and pyruvate oxidase (PyOx) on Au film electrodes by crosslinking with glutaraldehyde (GA) and evaluated electrochemically by cyclic voltammetry (CV) and fixed potential amperometry (CA). First, the experimental conditions were optimized in terms of applied potential, enzyme ratio PyK:PyOx and enzyme substrate concentration: phosphoenolpyruvate (PEP) and adenosine diphosphate (ADP). The biosensor sensitivity towards PEP detection was 2.11 ± 0.08 μA mM-1 cm-2, with very high reproducibility and repeatability, which made it suitable for inhibition studies of PyK inhibitor. The inhibition mechanism of shikonin was determined in relation to both PEP and ADP, with the calculation of IC50 values and binding constants (Ki). Detection of shikonin was possible at very low concentrations in the linear range of 0.1-4.0 pM. The electrochemical results were validated by UV-Vis spectrophotometry. The developed biosensor is a valuable tool for drug screening by enabling enzyme catalytic function examination with applicability to identify inhibitors, estimate their affinity, inhibition mechanism linked to their molecular mechanisms of action and evaluate selectivity, of great interest in both pharmaceutical and medical domains.

Targeting mitochondria-regulated ferroptosis: A new frontier in Parkinson's disease therapy

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the progressive loss of dopaminergic neurons in the substantial nigra. Mitochondrial dysfunction and mitochondrial oxidative stress are central to the pathogenesis of PD, with recent evidence highlighting the role of ferroptosis - a type of regulated cell death dependent on iron metabolism and lipid peroxidation. Mitochondria, the central organelles for cellular energy metabolism, play a pivotal role in PD pathogenesis through the production of Reactive oxygen species (ROS) and the disruption of iron homeostasis. This review explores the intricate interplay between mitochondrial dysfunction and ferroptosis in PD, focusing on key processes such as impaired electron transport chain function, tricarboxylic acid (TCA) cycle dysregulation, disruption of iron metabolism, and altered lipid peroxidation. We discuss key pathways, including the role of glutathione (GSH), mitochondrial ferritin, and the regulation of the mitochondrial labile iron pool (mLIP), which collectively influence the susceptibility of neurons to ferroptosis. Furthermore, this review emphasizes the importance of mitochondrial quality control mechanisms, such as mitophagy and mitochondrial biogenesis, in mitigating ferroptosis-induced neuronal death. Understanding these mechanisms linking the interplay between mitochondrial dysfunction and ferroptosis may pave the way for novel therapeutic approaches aimed at preserving mitochondrial integrity and preventing neuronal loss in PD.

Epigenome-wide association study identifies a specific panel of DNA methylation signatures for antenatal and postpartum depressive symptoms

Depression during pregnancy and postpartum poses significant risks to both maternal and child well-being. The underlying biological mechanisms are unclear, but epigenetic variation could be exploited as a plausible candidate for early detection. We investigated whether DNA methylation signatures are associated with antenatal depressive symptoms (ADS) and whether early alterations in methylation patterns could be used to predict postpartum depressive symptoms (PDS). 201 pregnant women in early pregnancy, without a prior history of depressive disorders, from the STratification of Risk of Diabetes in Early Pregnancy study (STRiDE) were recruited. Using the Patient Health Questionnaire-9 (PHQ-9), 92 women were identified with ADS, while 109 served as controls. Edinburgh Postnatal Depression Scale (EPDS) was used to assess PDS during 6-12 weeks after delivery. The dataset was split into 80 % for training and testing and 20 % for validation, to discern potential CpGs for ADS using a support vector machine classifier. Analysis revealed 591 CpGs significantly associated with ADS, from which a panel of 7 CpGs was identified to discriminate between ADS and controls with high sensitivity and specificity (AUC: 0.85 in test, 0.73 in validation). Pathway analysis highlighted involvement in inositol phosphate metabolism, notch, and calcium signaling. The same 7 CpGs predicted PDS with an AUC of 0.76 (95 % CI: 0.66-0.87). Integration of CpG data with patient-reported information significantly enhanced PDS prediction. Our study identified DNA methylation signatures that could potentially differentiate ADS from controls and predict PDS. This suggests potential for developing a CpG panel for diagnostic and preventive strategies for perinatal depression.

Glucocorticoid reduces mortality in LPS-induced sepsis mouse model by inhibiting JAK1/STAT3-mediated inflammatory response and restoring tricarboxylic acid cycle

AIMS

Sepsis is characterized by a systemic inflammation disorder and multi-organ dysfunction caused by infection. Glucocorticoids (GCs), as anti-inflammatory properties drugs, are widely used for the management of patients with inflammatory diseases, including sepsis. However, the therapeutic effect and underlying mechanisms of GCs on sepsis remain incompletely understood.

MATERIALS AND METHODS

Mouse sepsis models were constructed using intraperitoneal injection of lipopolysaccharide (LPS) and treated with synthetic GC dexamethasone (DEX). Systemic inflammation and organ injury were evaluated by histological staining, immunophenotypic analysis, and detection of inflammatory cytokines. Inflammatory signaling pathways were identified by western blot (WB) and RT-qPCR. Finally, targeted metabolomics were conducted to examine metabolic changes.

KEY FINDINGS

Subcutaneous administration of DEX significantly alleviate LPS-induced acute organ injury and systemic inflammation, thereby reducing mortality in septic mice. DEX substantially reduced the amounts of intrahepatic neutrophils/macrophages, and inflammatory cytokines expressions in the livers of septic mice and in LPS-stimulated bone-marrow-derived macrophages (BMDMs). Mechanistically, DEX inhibit JAK1/STAT3 signaling pathway both in livers and BMDMs. Pharmacological inhibition of JAK1 or STAT3 via Upadacitinib or Stattic, respectively, partially mimic the anti-inflammatory function of GC, including the reduction of intrahepatic macrophages, proinflammatory cytokines production, and mortality in septic mice. Additionally, DEX could also promote the rewiring of tricarboxylic acid (TCA) cycle in the livers of septic mice.

SIGNIFICANCE

This study provides important insights into the molecular and metabolic mechanisms underlying GCs-mediated anti-inflammatory reactions.

Design, synthesis, and Biological evaluation of novel macrocyclic derivatives as potent ATP-citrate lyase inhibitors

ATP-citrate lyase (ACLY) is a key lipogenic enzyme involved in the synthesis of fatty acid and cholesterol, which converts cytosolic citrate to acetyl-CoA, a starting material for de novo lipogenesis. ACLY inhibitor is considered as potential therapeutic strategy for dyslipidemia and related diseases. In this study, we reported a series of novel macrocyclic derivatives as ACLY inhibitors, among them, compound 55 exhibited potent ACLY inhibitory activity (IC50 = 8.3 nM) and high binding affinity to ACLY. Notably, compound 55 demonstrated good pharmacokinetic profiles and potent in vivo hypolipidemic effect. Collectively, compound 55 deserved further development to provide potential candidate for treatment of hyperlipidemia and related diseases.

miR-125b-5p regulates FFA-induced hepatic steatosis in L02 cells by targeting estrogen-related receptor alpha

BACKGROUND & AIMS

NAFLD is a global and complex liver disease caused by multiple factors. Intrahepatocellular steatosis is the primary prerequisite for the occurrence and development of NAFLD. It has been shown that miR-125b-5p is highly correlated with NAFLD, and ESRRA is a factor that regulates lipid metabolism. The purpose of our study is to investigate whether miR-125b-5p regulates FFA-induced steatosis in L02 cells by targeting ESRRA.

APPROACHES AND RESULTS

Estrogen-related receptor alpha (ESRRA) was identified as a direct target of miR-125b-5p through database prediction and a dual-luciferase reporter gene assay. L02 cells were induced with free fatty acids (OA:PA, 2:1) at concentrations of 0.3 mM, 0.6 mM, 0.9 mM, 1.2 mM and 1.5 mM for 24 h, 48 h and 72 h, respectively. The degree of hepatocyte steatosis and triglyceride content were separately manifested by oil red O staining and colorimetric method. Cell viability per group was detected by CCK-8 assay. Eventually, 0.9 mM and 24 h were screened out as the optimal concentration and time for establishing the in-vitro model of hepatic steatosis. Followingly, miR-125b-5p and ESRRA were knocked down by transient transfection. We monitored the expressions of lipid metabolism factors SREBP-1c, ACC1 and FAS and determine triglyceride content within the cells per group. The data showed that knockdown of ESRRA led to down-regulation of the expressions of SREBP-1, ACC1, FAS and triglyceride content. Meanwhile, knockdown of ESRRA and miR-125b-5p resulted that the expressions of ESRRA, SREBP-1, ACC1, FAS and triglyceride content rebounded.

CONCLUSIONS

MiR-125b-5p down-regulates the expressions of lipid metabolism-related factors by negatively regulating ESRRA, thereby improving hepatic steatosis.

Enhancing the activity of γ-hydroxy lactone derivatives as innovative peroxisome proliferator-activated receptor γ non-agonists inhibiting cyclin-dependent kinase 5-mediated phosphorylation

Insulin resistance (IR) is a pathological condition in which tissues exhibit a reduced response to normal or elevated levels of insulin. Type 2 diabetes mellitus (T2DM) and Metabolic Syndrome are the most prevalent disorders associated with IR. Most of the glitazones, traditional anti-diabetic drugs acting as Peroxisome Proliferator-Activated Receptor γ (PPARγ) agonists, have been withdrawn from the market. To mitigate the serious adverse effects associated with PPARγ agonism, a new opportunity is represented by the inhibitors of PPARγ phosphorylation by the Cyclin-Dependent Kinase 5 (CDK5). Their mechanism of action is mediated by the stabilization of the PPARγ β-sheet containing Ser245. Recently, we identified 4-(4-bromophenyl)-3-hydroxy-5-(3-hydroxyphenyl)furan-2(5H)-one (I) as a PPARγ non-agonist, capable of blocking the phosphorylation of the enzyme without direct effects on either CDK5 or PPARγ. Here, we isolated the two enantiomers of I, unambiguously defined their absolute configuration through single crystal X-ray diffraction and demonstrated by Grating-Coupled Interferometry binding assays that both (S)-I and (R)-I exhibited comparable affinity for PPARγ. Then, a library of 12 analogs was designed through structure-based modifications, optimizing the interactions within the ligand-binding domain. GCI analysis identified derivative 11, featuring an oxyacetic group in place of the initial hydroxyl function of the reference compound I, as the most promising candidate (KD = 186 nM). The crystal structure of the PPARγ-LBD/11 complex revealed a hydrogen bond interaction with Arg280, further stabilizing the binding conformation. These findings highlight the potential of γ-hydroxy lactone derivatives as PPARγ modulators and provide a foundation for future drug development targeting IR.

Hit to lead optimization of isopentenyl chalcones as novel MTHFD2 inhibitors for cancer treatment: design, synthesis, in-vitro, in-vivo and in-silico studies

Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) plays a key role in one-carbon metabolism, as it is highly upregulated in cancer cells while exhibiting minimal expression in healthy adult tissues. Consequently, MTHFD2 is regarded as a promising target for cancer therapies. In this study, a series of isopentenyl chalcones, based on hit compound sophoradin, were designed and synthesized by computer-aided drug design. Preliminary structure-activities relationship revealed the great significance of chalcone scaffold and isopentenyl groups. The optimized compound 41, with an isopentenyl group and three hydroxyl groups, demonstrated remarkable activity and high selectivity in enzymatic assays (MTHFD1 IC50 = 19.05 ± 7.10 μM, MTHFD2 IC50 = 1.46 ± 0.28 μM, SI = 13). The cellular thermal shift assay implied that 41 could directly bind to MTHFD2. In vitro, compound 41 dramatically promoted intracellular ROS accumulation, and exhibited potent antiproliferative activity against lung cancer cells H1299 with low toxicity to BEAS-2B cells. Furthermore, 41 also demonstrated considerable anti-lung cancer efficacy in a mouse xenograft model and favorable pharmacokinetic properties without significant abnormalities in major organs. This work enriches the structure-activity relationship of MTHFD2 inhibitors and provides a potential candidate for cancer treatment.

MTHFD2: A metabolic checkpoint altering trophoblast invasion and migration by remodeling folate-nucleotide metabolism in recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) affects female reproduction worldwide, yet its pathological mechanisms are still unclear. It has been reported that cellular metabolism reprogramming is a critical step for trophoblasts during embryo implantation. Herein, MTHFD2 was recognized as a key metabolic checkpoint attributed to RSA occurrence. This work figured out that the expression level of MTHFD2 was significantly inhibited in villus tissues from RSA patients, suggesting the potential role of MTHFD2 in RSA occurrence. Moreover, MTHFD2 knockdown impaired cellular folate-nucleotide metabolism, induced the accumulation of AICAR, and thereby impairing the EMT process to inhibit the invasion and migration of trophoblasts Besides, the AICAR accumulation further activated the downstream AMPK which deactivated the JAK/STAT/Slug pathway and ultimately deactivated the EMT process. Using a mouse model, MTHFD2 inhibition was observed to induce embryo implantation failure in vivo. Our results highlighted MTHFD2 as a metabolic checkpoint that remodeled folate-nucleotide metabolism to regulate the EMT process and ultimately altered the migration and invasion of trophoblasts in RSA occurrence. Our findings suggested that MTHFD2 was a promising therapeutic target in recurrent spontaneous abortion treatment.

Metal ions-induced programmed cell death: how does oxidative stress regulate cell death?

In recent years, the mechanisms of ferroptosis and cuproptosis, two novel modes of cell death, have been elucidated and have attracted much attention. Ferroptosis is dependent on the metabolic disruption of iron ions and lipid peroxidation, whereas cuproptosis is closely related to intracellular accumulation of copper ions, aggregation of lipoylated proteins and damage to FeS cluster proteins. In particular, oxidative stress plays an important role in both types of cell death. During ferroptosis, the central role of oxidative stress is reflected in the overproduction of reactive oxygen species (ROS) and lipid peroxidation of the cell membrane. Recent studies have revealed that ROS can propagate over long distances across cells in the form of trigger waves, triggering large-scale ferroptosis. In embryonic development, different regional redox states can limit the long-distance propagation of ferroptosis waves, which is critical for muscle remodeling and tissue formation during development. In cuproptosis, processes such as copper ions accumulation, tricarboxylic acid (TCA) cycle blockade, and reduced level of FeS cluster proteins are closely associated with oxidative stress. In addition, there is a close link between oxidative stress and death induced by other metal ions (Ca2+, Zn2+, etc.). In this paper, we review the role of oxidative stress in ferroptosis and cuproptosis and the related research progress to provide new ideas for understanding the mechanism of cell death and the occurrence and treatment of related diseases.

STUB1-mediated ubiquitination of SLC25A10 regulates mitochondrial function and drives osteosarcoma progression: A novel therapeutic target

Osteosarcoma (OS) is a highly aggressive primary bone malignancy characterized by limited treatment options and poor clinical outcomes. Emerging evidence underscores the critical role of mitochondrial metabolism in tumor progression, positioning mitochondrial proteins as potential therapeutic targets. SLC25A10, a mitochondrial dicarboxylate carrier involved in redox homeostasis and fatty acid synthesis, has been implicated in various cancers; however, its role in OS remains unclear.In this study, we investigated the function of SLC25A10 in OS progression and its potential as a therapeutic target. Our results revealed that SLC25A10 expression is significantly upregulated in OS tissues and cell lines compared to normal bone tissue, and its elevated expression is associated with poor patient prognosis. Functional assays demonstrated that silencing SLC25A10 via shRNA or CRISPR/Cas9 significantly suppressed OS cell proliferation, migration, and mitochondrial function, resulting in mitochondrial membrane depolarization, oxidative damage, and apoptosis. In contrast, SLC25A10 overexpression promoted OS cell proliferation and migration. In vivo, knockout of SLC25A10 markedly inhibited the growth of subcutaneous OS xenografts in nude mice.Furthermore, we identified STUB1, an E3 ubiquitin ligase, as a negative regulator of SLC25A10. STUB1 knockdown reduced the ubiquitination of SLC25A10, leading to increased protein stability and elevated expression. Notably, lysine 254 (K254) was identified as a key site mediating STUB1-dependent ubiquitination of SLC25A10. STUB1-mediated downregulation of SLC25A10 suppressed OS cell proliferation and migration, indicating a tumor-suppressive role for STUB1 in OS through modulation of SLC25A10.Collectively, our findings demonstrate that SLC25A10 is essential for maintaining mitochondrial function and contributes to OS malignancy. Targeting SLC25A10 may represent a novel and promising therapeutic strategy for the treatment of osteosarcoma.

Water Transport and Enzyme Recycling in Tenebrio molitor Midgut: Insights From Transcriptomics, Proteomics, and In Vivo Inhibition Assays

The low excretory rates of secreted digestive enzymes, such as trypsins, in insect species with peritrophic membranes led to the hypothesis of ectoperitrophic countercurrent water fluxes causing enzyme recycling. The midgut water flux model of Tenebrio molitor (T. molitor) is revisited and supported by in vivo experiments. Sequences from proteins putatively involved in water transport were retrieved from the T. molitor transcriptome by Blast and analyzed using bioinformatics tools. Gene expression of selected proteins was determined in three midgut sections (anterior, AM; middle, MM; posterior, PM) by RNA-seq, and transporter proteins were verified in microvillar-membrane-enriched midgut samples by proteomics. Genes encoding three cation chloride cotransporters (CCC) and four aquaporins were expressed in the midgut. TmNaCCC2, TmPrip, and TmEglp1 showed higher expression in the front half, while TmKCC, TmNKCC1, TmDrip, and TmEglp2 were more highly expressed in the back half. However, only TmNaCCC2 was found by proteomics. Midgut water fluxes were quantified by feeding T. molitor larvae with nonabsorbable dye and measuring its concentration along the midgut. The results suggest water absorption in AM and secretion in MM and PM, potentially caused by TmNaCCC2 and TmPrip in AM, and TmKCC and TmDrip in PM, whereas MM serves as a transition region. Larvae fed on furosemide, an NKCC and KCC inhibitor, showed altered midgut water fluxes, resulting in higher trypsin excretion into the hindgut, thus reinforcing the hypothesis of a countercurrent water flux generated by CCCs powering enzyme recycling in insect midguts.

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition; this phenomenon is known as cerebral ischemia-reperfusion injury. Current studies have elucidated the neuroprotective role of the sirtuin protein family (Sirtuins) in modulating cerebral ischemia-reperfusion injury. However, the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional exploration. In this review, the origin and research progress of Sirtuins are summarized, suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury, including inflammation, oxidative stress, blood-brain barrier damage, apoptosis, pyroptosis, and autophagy. The therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways, such as nuclear factor-kappa B signaling, oxidative stress mediated by adenosine monophosphate-activated protein kinase, and the forkhead box O. This review also summarizes the potential of endogenous substances, such as RNA and hormones, drugs, dietary supplements, and emerging therapies that regulate Sirtuins expression. This review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk factors. While Sirtuins show promise as a potential target for the treatment of cerebral ischemia-reperfusion injury, most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans, potentially influencing the efficacy of Sirtuins-targeting drug therapies. Overall, this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

Dynamic changes of hippocampal dendritic spines in Alzheimer's disease mice among the different stages

Alzheimer's disease (AD) is characterized by the accumulation of amyloid-β (Aβ) peptides and a progressive decline in cognitive function. Hippocampus as a crucial brain area for learning and memory, is also adversely affected by AD's pathology. The accumulation of Aβ is often associated with the loss of dendritic spines of the hippocampus. However, the dynamic alterations in dendritic spines throughout AD progression are not fully understood. To investigate it, we conducted in-vivo imaging in two mouse models representing the early and late stages of AD pathology: young mice injected with Aβ1-42 oligomers and APP/PS1 transgenic mice. In the early-stage AD model, imaging was conducted at third- and fifth- weeks post-injection. In the late-stage AD model, a four-month imaging began at 14 months old. The imaging results showed spine elimination in both models. Notably, acute Aβ exposure was linked to heightened spine loss on secondary dendrites, while in the late stage the primary effect was on tertiary dendrites. Concurrently, with the metabolism of Aβ, cognition recovered to some extent by five weeks post Aβ1-42 exposure. These findings suggested that dendritic spine plasticity was impaired during the development of AD, as evidenced by increasing spine loss at different levels. However, the cognitive recovery observed in early-stage AD model mice may indicate a compensatory structural reorganization, highlighting the potential of early intervention to mitigate disease progression. Our results provide novel insights into the neurotoxic effects of Aβ1-42 and may contribute to the development of therapeutic strategies for AD.

TIGAR attenuates intervertebral disc degeneration via autophagy-mediated Keap1 degradation and Nrf2 nuclear translocation to suppress nucleus pulposus pyroptosis

Pyroptosis plays a pivotal role in intervertebral disc degeneration (IVDD) driven by oxidative-inflammatory cascades, inducing nucleus pulposus (NP) cell lysis through gasdermin-mediated pore formation and subsequent release of proinflammatory cytokines, including IL-1β and IL-18. TP53-induced glycolysis and apoptosis regulator (TIGAR) alleviates oxidative stress by scavenging reactive oxygen species (ROS); however, its involvement in the autophagy-pyroptosis axis mediating IVDD remains unclear. In this study, we aimed to investigate how TIGAR delays IVDD progression via the autophagy-pyroptosis axis. First, we discovered from the NP tissues collected from patients undergoing lumbar spine surgeries and mice with needle puncture-induced models that the expression of TIGAR was reduced in severely degenerated tissues. In the IL-1β-induced human NP cell, TIGAR knockdown exacerbated the degradation of the extracellular matrix and pyroptosis, whereas TIGAR overexpression reversed this phenomenon. Ultrastructural analysis via transmission electron microscopy (TEM) and autophagic flux quantification revealed TIGAR-mediated autophagy in NP cells under inflammatory conditions. Co-immunoprecipitation assays validated the formation of a Keap1-p62-ubiquitin ternary complex, which directed Keap1 toward lysosome-dependent degradation and enhanced Nrf2 nuclear translocation. Therapeutic intradiscal delivery of AAV-TIGAR attenuated IVDD progression in mouse models, evidenced by preserved disc height index and reduced histopathological scores. Collectively, this work identified TIGAR as a redox-sensitive molecular switch that mitigated oxidative stress and inflammasome-driven pyroptosis through Keap1 autophagic clearance, offering a novel therapeutic paradigm for precision-targeted IVDD intervention.

Per- and polyfluoroalkyl substances as potentiators of hepatotoxicity in an exposome framework: Current challenges of environmental toxicology

Chronic liver diseases, including metabolic dysfunction-associated steatosic liver disease (MASLD) and hepatocellular carcinoma (HCC), are on the rise, potentially due to daily exposure to complex mixtures of chemical compounds forming part of the exposome. Understanding the mechanisms involved in hepatotoxicity of these mixtures is essential to identify common molecular targets that may highlight potential interactions at the molecular level. We illustrated this issue with two families of environmental contaminants, per- and polyfluoroalkyl substances (PFAS) and heterocyclic aromatic amines (HAAs), both of which could be involved in the progression of chronic liver diseases, and whose toxicity may be potentiated by interactions at the level of xenobiotic metabolism. In the study of exposome effects on chronic liver disease, New Approach Methodologies (NAMs) including omics analyses and data from various in vitro, in vivo and in silico approaches, are crucial for improving predictivity of toxicological studies in humans while reducing animal experimentation. Additionally, the development of complex in vitro human liver cell models, such as organoids, is essential to avoid interspecies differences that minimize the risk for humans. All together, these approaches will contribute to construct Adverse Outcome Pathways (AOPs) and could be applied not only to PFAS mixtures but also to other chemical families, providing valuable insights into mixture hepatotoxicity prediction in the study of the exposome. A better understanding of toxicological mechanisms will clarify the role of environmental contaminant mixtures in the development of MASLD and HCC, supporting risk assessment for better treatment, monitoring and prevention strategies.

GSK621 ameliorates lipid accumulation via AMPK pathways and reduces oxidative stress in hepatocytes in vitro and in obese mice in vivo

INTRODUCTION

Metabolic-dysfunction-associated fatty liver disease (MAFLD) represents a broad spectrum of liver lipid metabolism disorders associated with metabolic homeostasis, inflammation, oxidative stress, and fibrogenesis. The incidence of MAFLD has increased in recent years, but there is a lack of effective treatment strategies. GSK621 shows potential as a novel adenosine-monophosphate-activated protein kinase (AMPK) agonist; however, its function in lipid metabolism has not yet been confirmed.

OBJECTIVES

This study aimed to determine the effects of GSK621 on liver lipid accumulation in vitro and vivo and explore the underlying mechanism of these effects.

METHODS

The function of GSK621 in lipid deposition was investigated in vitro with HepG2 cells and normal mouse liver cells (AML12), and in vivo using C57BL/6 J mice fed with a high-fat diet (60 % fat) for 8 weeks to establish a model of MAFLD, followed by GSK621 treatment for a further 8 weeks.

RESULTS

GSK621 treatment significantly improved hepatocyte steatosis via the AMPK-carnitine palmitoyl transferase 1 (CPT1A) pathway and decreased levels of reactive oxygen species (ROS) in cells, accompanied by elevated expression of antioxidative stress proteins. MAFLD mice showed significant improvements in liver steatosis after GSK621 treatment, as well as increased expression of liver proteins related to the AMPK pathway and antioxidative stress.

CONCLUSION

GSK621 can improve hepatocytes steatosis in vitro and vivo via the AMPK-CPT1A pathway by increasing lipid metabolism and augmenting expression of antioxidant-stress-related proteins to reduce ROS deposition.

USP18 is a key regulator of immune function in mouse midbrain microglia

AIMS

Ubiquitin-specific peptidase 18 (USP18) is an important member of the deubiquitinating enzyme family, which has received much attention in recent years for its role in microglia regulation. The aim of this study was to investigate the role of USP18 in midbrain and its potential molecular mechanisms.

METHODS

In this study, we assessed behavioural phenotypes and pathological changes by adeno-associated virus (AAV)-mediated midbrain-specific USP18 high-expression mouse model. RNA sequencing and untargeted metabolomics were used for multi-omics analysis, and protein expression was detected by Western blot, and ELISA was used to detect neuroinflammatory factor levels.

RESULTS

Our analyses suggest that USP18 is a key regulator of immune activity in the midbrain. USP18 helps maintain the resting state of microglia and exerts neuroprotective effects by promoting TH protein expression. In the midbrain, interference with USP18 expression resulted in significant changes in neuroimmune responses, gene expression associated with inflammation, and metabolite levels. Notably, the TLR signalling pathway was significantly enriched. Loss of USP18 led to a significant increase in the expression of TLR2, Iba-1, and GFAP proteins and a significant decrease in TH levels, and this change was particularly pronounced in microglia. Importantly, the changes observed in USP18 silencing were also reflected in brain tissues of human neurodegenerative diseases.

SIGNIFICANCE

This study reveals the critical role of USP18 in midbrain and microglia, and suggests it can finely regulate neuroinflammatory and immune responses by modulating TLR2 protein levels. The findings provide new ideas for understanding mechanisms of neurodegenerative diseases and developing therapeutic strategies.

Anoikis resistance in Cancer: Mechanisms, therapeutic strategies, potential targets, and models for enhanced understanding

Anoikis, defined as programmed cell death triggered by the loss of cell-extracellular matrix (ECM) and cell-cell interactions, is crucial for maintaining tissue homeostasis and preventing aberrant cell migration. Cancer cells, however, display anoikis resistance (AR) which in turn enables cancer metastasis. AR results from alterations in apoptotic signaling, metabolic reprogramming, autophagy modulation, and epigenetic changes, allowing cancer cells to survive in detached conditions. In this review we describe the mechanisms underlying both anoikis and AR, focusing on intrinsic and extrinsic pathways, disrupted cell-ECM interactions, and autophagy in cancer. Recent findings (i.e., between 2014 and 2024) on epigenetic regulation of AR and its role in metastasis are discussed. Therapeutic strategies targeting AR, including chemical inhibitors, are highlighted alongside a network analysis of 122 proteins reported to be associated with AR which identifies 53 hub proteins as potential targets. We also evaluate in vitro and in vivo models for studying AR, emphasizing their role in advancing metastasis research. Our overall goal is to guide future studies and therapeutic developments to counter cancer metastasis.

Engineered nanovesicles targeting SERPINE1 overcome temozolomide resistance in glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with limited treatment options due to its resistance to temozolomide (TMZ). This study explores a novel therapeutic approach using engineered cell membrane nanovesicles loaded with SERPINE1 inhibitors to combat TMZ resistance. High-throughput sequencing identified pivotal genes associated with resistance, while the nanovesicles demonstrated excellent stability and the ability to cross the blood-brain barrier. Functional assays revealed significant suppression of GBM cell viability, migration, and invasion, accompanied by reduced expression of SERPINE1 and VEGF, suggesting inhibition of angiogenesis and tumor progression. These findings highlight the potential of SERPINE1-targeted nanovesicles as an innovative and effective strategy for overcoming TMZ resistance in GBM.

Signaling balance of MCTs and GPR81 controls lactate-induced metabolic function and cell death in skeletal muscle cells through Ranbp3l/Nfat5 and Atf4

Lactate, a byproduct of pyruvate in the glycolytic pathway, has been recognized as a signaling molecule and a regulator of gene expression. In skeletal muscles, lactate is dynamically regulated during exercise and influences muscular function, including myogenic differentiation and metabolism. The effects of lactate vary depending on lactate levels, which are influenced by exercise intensity, type, and duration. Furthermore, the effects of lactate on cellular signaling are different during the stages of myogenic differentiation. However, the distribution of lactate signaling in terms of lactate concentration, signaling types, and myogenesis has not been fully elucidated. In this study, we investigated the dual effects of lactate on myogenic differentiation and viability using C2C12 cells and C57BL/6 mice. Low levels of lactate treatment promoted myogenesis in the early stage of C2C12 differentiation, while high lactate concentrations or treatment with 3,5-DHBA, a GPR81 agonist, impaired cell viability during late myogenic differentiation. Transcriptomic analysis and knockdown experiments revealed that lactate promotes myogenesis and muscular metabolic functions through the induction of Ranbp3l and Nfat5 expressions. On the other hand, the detrimental effects of lactate on cell survival are mediated by the GPR81-induced PI3K-Akt/ERK-Atf4 axis. GPR81 signaling also feeds forward the expression of Hcar1 via Akt and ERK. These dual actions of lactate on skeletal muscle were also observed in vivo through lactate or 3,5-DHBA injections and exercise training models. Our study concludes that maintaining a balance in lactate signaling is crucial for regulating skeletal muscle phenotypes in response to exercise and lactate treatments.

Sonodynamic activated nanoparticles with Glut1 inhibitor and cystine-containing polymer stimulate disulfidptosis for improved immunotherapy in bladder cancer

Disulfidptosis, a novel form of programmed cell death characterized by cystine accumulation and disulfide stress, primarily affects metabolically active tumors like bladder cancer, which is often considered to be a highly metabolic and energy-consuming tumor. However, translating disulfidptosis induction into clinical practice face substantial obstacles, including the limited solubility of key inducers, insufficient cystine buildup within cells, and cellular mechanisms regulating the NADP+/NADPH equilibrium. To fully unlock the therapeutic potential of disulfidptosis, a promising solution has emerged in the form of nanotechnology combined with sonodynamic therapy (SDT). This study reports a novel approach that enhances disulfidptosis through SDT, simultaneously promoting immunogenic cell death (ICD) and improving the immunosuppressive tumor microenvironment. The system, SPCP/CCP@Bay, comprises a degradable sonodynamic-pseudo-conjugate-polymer (SPCP) and a cystine-containing polymer (CCP), loaded with Bay-876. Following intravenous administration, SPCP/CCP@Bay effectively accumulates at tumor sites. Under ultrasound radiation, SPCP/CCP@Bay effectively releases Bay-876, disrupts the intracellular redox balance, releases cystine from CCP, and induces disulfidptosis. Moreover, SPCP/CCP@Bay induces ICD and synergizes with PD-1 monoclonal antibodies (α-PD-1) to suppress tumor growth. This integrated strategy holds significant promise in reshaping the tumor microenvironment, converting "cold tumors" to "hot tumors", and advancing the field of cancer immunotherapy.

Thrombospondin-1 modulation by Bifidobacterium spp. mitigates lung damage in an acute lung injury mouse model

Our study shows that Bifidobacterium spp. supplementation reduces lung damage in acute lung injury by enhancing immune cell activity and restoring thrombospondin-1 levels, offering a promising therapeutic approach for the treatment of ALI/ARDS.

BACKGROUND

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are critical conditions characterized by severe lung inflammation and damage, often exacerbated by mechanical ventilation. Probiotics, particularly those containing Bifidobacterium spp. (Bifidus) have shown promise in modulating immune responses and reducing inflammation.

METHODS

In this study, we investigated the effects of Bifidus supplementation in a mouse model of lipopolysaccharide induced ALI and ventilator-induced lung injury.

RESULTS

Our results demonstrate that Bifidus significantly ameliorates lung injury by enhancing efferocytosis and reducing pro-inflammatory cytokine levels. Single-cell RNA sequencing revealed significant changes in lung immune cell populations, particularly macrophages and monocytes, which showed increased efferocytosis activity and modulation of key signaling pathways such as TNF, MAPK and TLR. Notably, Bifidus feeding restored thrombospondin-1 levels in lung tissue, facilitating clearance of apoptotic cells and promoting resolution of inflammation.

CONCLUSIONS

Overall, our study highlights the potential of Bifidus as a therapeutic strategy to mitigate lung injury in ALI/ARDS.

Sequential simulation of regeneration-specific microenvironments using scaffolds loaded with nanoplatelet vesicles enhances bone regeneration

Bone regeneration is a complex and coordinated physiological process, and the different stages of this process have corresponding microenvironments to support cell development and physiological activities. However, biological scaffolds that provide different three-dimensional environments during different stages of bone regeneration are lacking. In this study, we report a novel composite scaffold (NPE@DCBM) inspired by the stages of bone regeneration; this scaffold was composed of a fibrin hydrogel loaded with nanoplatelet vesicles (NPVs), designated as NPE, and decellularized cancellous bone matrix (DCBM) microparticles. Initially, the NPE rapidly established a temporary microenvironment conducive to cell migration and angiogenesis. Subsequently, the DCBM simulated the molecular structure of bone and promoted new bone formation. In vitro, the NPVs regulated lipid metabolism in bone marrow mesenchymal stem cells (BMSCs), reprogramed the fate of BMSCs by activating the PI3K/AKT and MAPK/ERK positive feedback pathways, and increased BMSC functions, including proliferation, migration and proangiogenic potential. In vivo, NPV@DCBM accelerated bone tissue regeneration and repair. Initially, the NPE rapidly induced angiogenesis between DCBM microparticles, and subsequently, BMSCs differentiated into osteoblasts with DCBM microparticles at their core. In summary, the design of this composite scaffold that sequentially mimics different bone regeneration microenvironments may provide a promising strategy for bone regeneration, with clinical translational potential.

Antidiabetic constituents of Kaempferiae rhizoma: Previously undescribed O-linked diarylheptanoid dimers promoting GLP-1 secretion via PKA-CREB pathway

Glucagon-like peptide-1 (GLP-1) is a fascinating target for the treatment of diabetes to avoid hypoglycemia. Kaempferiae Rhizoma (KR), the dried rhizomes of Kaempferia galanga, is a famous pungent medicine used for activating Qi, warming interior, removing digestion and relieving pain in China. In order to characterize the antidiabetic effects of KR, 21 previously undescribed O-linked diarylheptanoid dimers, kaemgalangins A1-A4 (1-4), B1-B13 (5-17) and C1-C4 (18-21), were isolated from the ethyl acetate fraction. Their structures were determined by extensive spectroscopic analyses, quantum computation and chemical methods. All compounds were tested for their GLP-1 stimulating effects on NCI-H716 cells, most of which showed obvious activity representing a new type of antidiabetic constituents. Especially, compounds 1, 2 and 16 showed spectacular GLP-1 stimulation with promoting rates of 146.6 ± 31.1 %, 159.0 ± 16.6 % and 142.9 ± 2.7 %, more potent than the positive control. Mechanism study manifested that kaemgalangin A1 (1) promoted GLP-1 secretion through up-regulating the mRNA expression of Gcg and Pc1/3, and the phosphorylation of PKA and CREB, but independent on TGR5 and GPR119 receptors. Furthermore, network pharmacology analysis suggested that the GLP-1 secretion induced by 1 was closely related to MAPK and PI3K-Akt signaling pathways. This investigation first revealed that KR was rich in diarylheptanoid dimers with GLP-1 promoting effects, which provides scientific basis for the antidiabetic application of K. galanga.

Macrophage response to fibrin structure mediated by Tgm2-dependent mitochondrial mechanosensing

Following an injury at the implantation position, blood-material interactions form a fibrin architecture, which serves as the initial activator of foreign body response (FBR). However, there is limited knowledge regarding how the topography of fibrin architectures regulates macrophage behavior in mitigating FBR. Mechanical cues of the microenvironment have been reported to shape immune cell functions. Here, we investigated macrophage mechanobiology at the organelle level by constructing heterogeneous fibrin networks. Based on findings in vivo, we demonstrated that adhesion-mediated differentiation of mitochondrial function modulated macrophage polarization. The finite activation of integrin signaling upregulated transglutaminase 2 (Tgm2) in a trans-manner, augments PGC1α-mediated mitochondrial biogenesis. Our study highlighted the previously overlooked spatial structures of host proteins adsorbed on material surfaces, advocating for a paradigm shift in material design strategies, from focusing solely on physical properties to considering the modification of host proteins.

Roxadustat pre-conditioning and cyclic uniaxial stretching improve tenogenic differentiation potential of human adipose derived mesenchymal stromal cells

Tendon injuries represent a significant challenge to treat owing to their limited intrinsic reparative capacity. The use of mesenchymal stem cells (MSC) offers promising alternative therapeutic option to augments tendon repair. It is hypothesised that the activation of hypoxia inducible factor-1 alpha (HIF-1α), could facilitate the tendon repair process by promoting the proliferation and tenogenic differentiation of MSCs. To demonstrate this, a study was conducted incorporating the use of Roxadustat, a specific hypoxia mimetic mediator and cyclic uniaxial stretching at a frequency of 1 Hz and 8 % strain on adipose derived-mesenchymal stromal cells (ADMSCs).

METHODS

Cellular morphology, proliferation rate, tenogenic protein and gene expression levels from 8 different treatment groups were compared. These groups include untreated ADMSCs (Control), Roxadustat pre-conditioned ADMSCs (ROX), ADMSCs subjected CAY10585 treatment only (CAY), Roxadustat pre-conditioned ADMSCs with CAY10585 inhibition (ROX+CAY), ADMSCs subjected to uniaxial stretching only (S), Roxadustat pre-conditioned ADMSCs with uniaxial stretching (ROX+S), ADMSCs subjected CAY10585 with uniaxial stretching (CAY+S) and primary tenocytes (Tenocytes).

RESULTS

ROX+S group exhibited the highest expression of HIF-1α and demonstrated a significant up-regulation of collagen I and III expressions, increasing by 4.9 and 5.6-fold compared to ROX group, respectively. There is a significant increase of SCX, TNC, TNMD, COLI and COLIII expression in this combination treatment group; (SCX= 9.9, TNC= 12.6, TNMD= 7.0, COLI= 8.0 and COLIII= 10.0-fold). Conversely, the expression of the markers markedly reduced with HIF-1α inhibitor CAY10585. However, uniaxial stretching effectively counteracted the inhibitory effects of CAY10585 in the CAY+ S group, resulting in a 3.9-fold increase in SCX expression compared to CAY treatment alone.

CONCLUSION

HIF-1α accumulation promotes superior tenogenic differentiation of ADMSCs, suggesting that the combination of Roxadustat and cyclic uniaxial stretching may be a potential therapeutic mediator in tendon repair strategies.

FMO3 exacerbates hepatic endoplasmic reticulum stress in drug-induced liver injury by inhibiting CREB3/P4HB axis and activating TMAO-mediated PERK pathway

AIMS

The primary objective of this study is to elucidate the role of FMO3, an important enzyme in drug metabolism, and its metabolites in Drug-induced liver injury (DILI).

MATERIALS AND METHODS

We overexpressed hepatic FMO3 in mice by injecting AAV8 to examine their liver morphology under acetaminophen (APAP) or monocrotaline (MCT) treatment. We also detected the metabolite TMAO of FMO3 in patients and mice with DILI, and further verified its regulatory effects on the endoplasmic reticulum stress pathway in hepatocytes through in vivo and in vitro experiments.

KEY FINDINGS

We found that FMO3 is upregulated in patients and male mice with DILI and overexpression of hepatic FMO3 exacerbates APAP or MCT-induced acute liver injury in mice. Mechanistically, FMO3 binds to endoplasmic reticulum (ER) stress-related transcription factor CREB3 (cAMP response element-binding protein 3) and inhibits its nuclear transcription. The decreased activity of CREB3 reduces the expression of the downstream gene P4HB(prolyl 4-hydroxylase subunit beta), subsequently inducing ER stress and apoptosis. Trimethylamine N-Oxide (TMAO), as a metabolite of FMO3, is also significantly elevated in patients with pyrrolizidine alkaloids-induced acute liver injury and APAP or MCT-induced liver injury in male mice. TMAO triggers ER stress by activating the PERK signaling pathway, and inhibiting TMAO production in DILI mice mitigates liver injury.

SIGNIFICANCE

Overall, the above findings identify FMO3 as a potential enzyme that facilitates the progression of DILI and exerts ER stress by CREB3/P4HB axis and its metabolites TMAO, which presents new therapeutic targets for DILI.

A double-blind, placebo-controlled trial of exenatide for the treatment of olanzapine-related weight gain in obese and overweight adults

OBJECTIVE

To assess the safety and efficacy of exenatide in overweight or obese patients treated with olanzapine.

METHODS

Adults with stable major mood or psychotic disorders were randomized to double-blind exenatide or placebo for 16 weeks. Weight and body mass index (BMI) were monitored throughout the study. A secondary objective was to evaluate the tolerability of exenatide and its effects on mood and psychotic symptoms.

RESULTS

A significant difference in weight change was detected between the treatment groups. Participants in the exenatide group experienced on average a minor weight loss, while participants in the placebo group on average experienced weight gain (-0.5 kg [-0.6 %] vs. +2.6 kg [+2.8 %], both p < .01). The most common side effects in the exenatide group were gastrointestinal symptoms and headaches. There were no clinically meaningful differences between the groups in changes to mood or psychotic symptoms.

CONCLUSIONS

Exenatide is effective and well-tolerated for attenuating olanzapine-associated weight gain.

CLINICAL TRIAL REGISTRATION INFORMATION

Exenatide for the Treatment of Weight Gain Associated with Olanzapine in Obese Adults. NCT00845507.

Effectiveness of 8-hour time-restricted eating combined with different dietary patterns on body composition, lipid metabolism, and oxidative stress in healthy adults: An exploratory study from an RCT

OBJECTIVES

To evaluate the effectiveness of a 4-week intervention of time-restricted eating (TRE) alone or in combination with an elimination of ultra-processed foods or vegetarian diet, on body composition, lipid metabolism, and oxidative stress.

METHODS

This was a randomized controlled trial including 70 participants comparing three diet groups maintained for a 4-week period: A, TRE alone; B, TRE with elimination of ultra-processed foods; and C, TRE with a vegetarian diet. Per-protocol analyses of body composition, plasma lipid levels, and oxidative stress markers were performed.

RESULTS

Compared to baseline, Group B significantly reduced weight (P = 0.02), body mass index, waist and hip circumference, as well as fat ratio, total cholesterol, 4-hydroxynonenal an 8-Iso prostaglandin F 2α (all P < 0.05). Group B also increased high-density lipoprotein cholesterol (P < 0.05) and catalase (P = 0.002). Compared to Group A, Group B was more effective in decreasing body mass index (Δ: -0.1 ± 0.7 vs. -0.2 ± 0.3, respectively, P = 0.041) and waist circumference (Δ: -1.1 ± 4.0 vs. -3.5 ± 4.4, P < 0.001). Compared to Group A and B, the increase in superoxide dismutase (Δ: 12.74 ± 8.34, P < 0.05) and glutathione (Δ: 0.63 ± 0.40, P < 0.05) was significantly greater for Group C. Group C also produced a greater decrease in malondialdehyde (Δ: -0.79 ± 0.28) than the Group A (Δ: -0.32 ± 0.51, P < 0.001) and Group B (Δ: -0.20 ± 0.68, P < 0.001) diets.

CONCLUSIONS

Consumption of ultra-processed foods can increase body composition and lipid profile, despite TRE. A vegetarian diet in combination with TRE is effective in reducing oxidative stress injury.

Neuronal regulated cell death in aging-related neurodegenerative diseases: key pathways and therapeutic potentials

Regulated cell death (such as apoptosis, necroptosis, pyroptosis, autophagy, cuproptosis, ferroptosis, disulfidptosis) involves complex signaling pathways and molecular effectors, and has been proven to be an important regulatory mechanism for regulating neuronal aging and death. However, excessive activation of regulated cell death may lead to the progression of aging-related diseases. This review summarizes recent advances in the understanding of seven forms of regulated cell death in age-related diseases. Notably, the newly identified ferroptosis and cuproptosis have been implicated in the risk of cognitive impairment and neurodegenerative diseases. These forms of cell death exacerbate disease progression by promoting inflammation, oxidative stress, and pathological protein aggregation. The review also provides an overview of key signaling pathways and crosstalk mechanisms among these regulated cell death forms, with a focus on ferroptosis, cuproptosis, and disulfidptosis. For instance, FDX1 directly induces cuproptosis by regulating copper ion valency and dihydrolipoamide S-acetyltransferase aggregation, while copper mediates glutathione peroxidase 4 degradation, enhancing ferroptosis sensitivity. Additionally, inhibiting the Xc- transport system to prevent ferroptosis can increase disulfide formation and shift the NADP + /NADPH ratio, transitioning ferroptosis to disulfidptosis. These insights help to uncover the potential connections among these novel regulated cell death forms and differentiate them from traditional regulated cell death mechanisms. In conclusion, identifying key targets and their crosstalk points among various regulated cell death pathways may aid in developing specific biomarkers to reverse the aging clock and treat age-related neurodegenerative conditions.

Manganese dioxide coupled metal-organic framework as mitophagy regulator alleviates periodontitis through SIRT1-FOXO3-BNIP3 signaling axis

Periodontitis is a prevalent chronic inflammatory disease characterized by alveolar bone resorption. Its progression is closely linked to oxidative stress where reactive oxygen species (ROS) generated by mitochondria exacerbate inflammation in positive feedback loops. Strategies for mitochondrial regulation hold potential for therapeutic advances. Metal-organic frameworks (MOFs) have shown promise as nanozymes for ROS scavenging. However, inability to directly regulate cellular processes to prevent further ROS production from damaged mitochondria during persistent inflammation makes MOFs insufficient in treating periodontitis. This study synthesizes MnO2@UiO-66(Ce) by introducing MnO2 within nanoscale mesoporous UiO-66 type MOFs. MnO2 coupled with Ce clusters in MOF channels, forms a superoxide dismutase/catalase cascade catalytic system. More importantnly, manganese endows the MOFs with bioactive effects which enhances mitophagy, facilitating the removal of damaged mitochondria, thereby restoring long-term cellular homeostasis. The results demonstrate that this synergistic antioxidant solution MnO2@UiO-66 restores mitochondrial homeostasis and osteogenic activity of periodontal ligament cells in vitro and alleviates inflammatory bone resorption in a ligature-induced periodontitis model in vivo. The SIRT1-FOXO3-BNIP3 signaling axis plays a key role in this process. This study may provide a design strategy that combines a highly efficient cascade catalytic system with long-term regulation of cellular homeostasis to combat oxidative stress in chronic inflammation.

A novel FTO-targeting nanodrug induces disulfidptosis and ameliorates the suppressive tumor immune environment to treat uveal melanoma

Uveal melanoma (UM) is the most prevalent primary ocular malignancy in adults, with high lethality and limited effective treatment options. Despite identified driver mutations in GNAQ, GNA11, and BAP1, therapeutic advancements have been minimal. This study highlights the pivotal role of N6-methyladenosine (m6A) modifications in UM pathogenesis and progression, focusing on the demethylase FTO as a therapeutic target. Elevated FTO expression in UM tissues correlates with decreased m6A levels, increased aggressiveness, and poor prognosis. The FTO inhibitor meclofenamic acid (MA) restored m6A levels, upregulated SLC7A11, and induced disulfidptosis, a unique form of cell death triggered by GSH depletion and NADPH consumption. To address MA's limitations in bioavailability and tumor targeting, we developed an MA-loaded nucleic acid nanodrug (SNAMA). SNAMA demonstrated effective tumor growth inhibition in orthotopic and metastatic UM models through GSH-responsive release and m6A-mediated disulfidptosis activation. Incorporating a PD-L1 aptamer into SNAMA further improved tumor targeting and immune modulation, enhancing therapeutic efficacy. This study identifies FTO as a critical target for UM therapy and introduces SNAMA-apt as a promising nanodrug. The findings offer a foundation for m6A-targeted approaches in UM and other malignancies, addressing bioavailability, targeting, and immune evasion challenges.

Mitochondrial damage and ER stress in CB1 receptor antagonist-induced apoptosis in human neuroblastoma SH-SY5Y cells

Cannabinoid receptor type 1 (CB1R) is the key modulator of neuronal viability. CB1R antagonists provide neuroprotective effects on neurotoxicity caused by e.g. neuronal injury. However, the underlying mechanisms and potential limitations of CB1R antagonism remain unclear. Here we investigated the impact of environmental conditions on CB1R antagonist effects. We have found that cell-permeable CB1R antagonists, rimonabant and AM251, induced cell death in human neuroblastoma SH-SY5Y cells under serum-free conditions. Mitochondrial morphological analysis revealed mitochondrial swelling characterized by their network fragmentation and cristae reduction. Phosphoproteomics analysis showed the ER stress signaling pathway PERK/eIF2α/ATF4/CHOP, leading to caspase-dependent apoptosis. These results suggest that CB1R antagonists promote apoptosis via mitochondrial damage and ER stress under serum-free conditions in SH-SY5Y cells. Our findings indicate that while CB1R antagonists may be neuroprotective in certain conditions, they may also pose a neurotoxic risk in environments characterized by cellular stress or nutrient deprivation.

Bidirectional modulation of glycolysis using a multifunctional nanocomposite hydrogel promotes bone fracture healing in type 2 diabetes mellitus

Fracture healing in patients with type 2 diabetes mellitus (T2D) is markedly impaired, characterized by a prolonged inflammation phase and defective osteoblast differentiation at the fracture site. In this study, we identified aberrant cellular glycolysis at T2D fracture sites, with bone marrow mesenchymal stem cells (BMSCs) exhibiting suppressed glycolysis and macrophages displaying enhanced glycolysis, mediated by the dysregulation of hypoxia-inducible factor-1α (HIF-1α). To rectify these metabolic imbalances, we developed a multifunctional nanocomposite PN@MHV hydrogel. Myricitrin, a flavonoid glycoside, forms the MHV hydrogel by cross-linking with HA-PBA and PVA via hydrogen bonds, and upregulates glycolysis through HIF-1α, thus promoting osteoblast differentiation under high glucose environment. To further regulate the inflammatory microenvironment, we incorporated nanoparticles loaded with PX-478, a HIF-1α specific inhibitor, into the hydrogel, with folic acid covalently modified to target proinflammatory M1 macrophages. This PN@MHV hydrogel bidirectionally regulated glycolysis via HIF-1α, enhancing osteoblast differentiation while attenuating macrophage-mediated inflammation. Comprehensive in vitro and in vivo experiments in a T2D fracture mouse model confirmed the hydrogel's ability to improve the inflammatory microenvironment and accelerate bone healing. Our findings underscore the therapeutic potential of targeting cellular glycolysis as a promising approach for enhancing fracture healing in diabetic patients.

Connecting the dots: Mitochondrial transfer in immunity, inflammation, and cancer

Mitochondria are more than mere energy generators; they are multifaceted organelles that integrate metabolic, signalling, and immune functions, making them indispensable players in maintaining cellular and systemic health. Mitochondrial transfer has recently garnered attention due to its potential role in several physiological and pathological processes. This process involves multiple mechanisms by which mitochondria, along with mitochondrial DNA and other components, are exchanged between cells. In this review, we examine the critical roles of mitochondrial transfer in health and disease, focusing on its impact on immune cell function, the resolution of inflammation, tissue repair, and regeneration. Additionally, we explore its implications in viral infections and cancer progression. We also provide insights into emerging therapeutic applications, emphasizing its potential to address unmet clinical needs.

Bio-orthogonal-labeled exosomes reveals specific distribution in vivo and provides potential application in ARDS therapy

Exosomes derived from specific cells may be useful for targeted drug delivery, but tracking them in vivo is essential for their clinical application. However, their small size and complex structure challenge the development of exosome-tracking techniques, and traditional labeling methods are limited by weak affinity and potential toxicity. To address these issues, here we developed a novel bio-orthogonal labeling strategy based on phosphatidylinositol derivatives to fluorescently label exosomes from various human and mouse cell types. The different cell-derived exosomes revealed organ-specific distribution patterns and a favorable safety profile. Notably, 4T1 cell-derived exosomes specifically targeted the lungs. When used as drug carriers loaded with anti-inflammatory resveratrol, these exosomes showed significant therapeutic efficacy in mice with acute respiratory distress syndrome (ARDS), effectively reducing inflammatory responses, mitigating pulmonary fibrosis, and restoring lung tissue morphology and function. Our findings provide a novel exosome labeling strategy and an invaluable tool for their in vivo tracking and targeting screening, while exosomes that specifically target the lungs offer a potential therapeutic strategy for organ-specific diseases such as ARDS.

Design and rationale of the CORE-TIMI 72a and CORE2-TIMI 72b trials of olezarsen in patients with severe hypertriglyceridemia

BACKGROUND

Severe hypertriglyceridemia (HTG), defined as a serum triglyceride (TG) concentration ≥500 mg/dl, is present in approximately 1 in every 100 individuals and carries direct clinical consequences, including pancreatitis, which can be life-threatening. Olezarsen is an investigational antisense oligonucleotide targeted to the mRNA for apolipoprotein C-III (apoC-III), a protein known to impair TG clearance by inhibiting lipoprotein lipase and the hepatic uptake of triglyceride-rich remnants. No dedicated trial has tested olezarsen in patients with severe HTG.

METHODS

In these 2 pivotal phase 3 trials, CORE-TIMI 72a and CORE2-TIMI 72b, patients with severe HTG were randomized in a 2:1 fashion to either olezarsen (80 mg or 50 mg dose) or matching placebo. Patients will be treated for a total of 12 months and evaluated for the primary endpoint of percent change in TGs from baseline to 6 months compared with placebo. Pooled analyses of CORE and CORE2 will also assess olezarsen's effect on acute pancreatitis events and change in hepatic steatosis.

RESULTS

A total of 617 subjects in CORE-TIMI 72a and 446 subjects in CORE2-TIMI 72b were randomized. In these 2 trials, the median age was 54 and 55 years, women made up 24% and 23% of the study population, and the baseline TGs were 836 mg/dl and 749 mg/dl, respectively. A total of 333 subjects, 129 from CORE-TIMI 72a and 204 from CORE2-TIMI 72b, were enrolled in the hepatic MRI substudy.

DISCUSSION

Together, CORE-TIMI 72a and CORE2-TIMI 72b are designed to establish the efficacy and safety of olezarsen in patients with severe HTG.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT05079919 and NCT05552326.

Interactive effects of light at night and high fructose intake on the central circadian clock and endocrine outputs in rats

Light pollution is an increasing global environmental risk factor that contributes to the recent burden of metabolic diseases. The underlying mechanisms are not understood, but disruption of circadian control of physiological and behavioural processes may be involved. The negative consequences of chronodisruption can be augmented by co-exposure to high energy intake. Therefore, we investigated the individual and combined effects of artificial light at night (ALAN) and 10 % fructose in drinking water on the central clock in the suprachiasmatic nuclei (SCN) of the hypothalamus and circadian hormonal outputs in male rats. After 10 weeks of ALAN exposure and high fructose intake, the clockwork in the SCN was attenuated as indicated by eliminated day/night differences in the core clock gene Per1. Additionally, ALAN suppressed the daily variability and fructose induced upregulation of a gamma-aminobutyric acid-synthesising enzyme (GAD65), potentially affecting inhibitory neurotransmission in the SCN. ALAN and fructose additively inhibited plasma melatonin levels revealing excessive fructose intake as a chronodisruptive factor that can be potentiated by ALAN. In contrast to melatonin, daytime plasma testosterone concentrations were increased by high fructose and supressed by ALAN. Furthermore, high fructose intake elevated the plasma levels of two adipokines, leptin and adiponectin, but this response was absent specifically during the daytime in rats exposed to ALAN, indicating that ALAN reduced adipose tissue responsiveness. Our results document the complex consequences of ALAN and high fructose intake on endocrine control mechanisms that can have a long-term negative impact on metabolic health.

Mitochondrial translocator-protein ligand etifoxine reduces pain symptoms and protects against motor dysfunction development following peripheral nerve injury in rats

Peripheral nerve injury enhances mitochondrial translocator protein (TSPO) expression in the spinal cord and dorsal root ganglia (DRG), which is associated with neuroinflammation and mitochondrial dysfunction contributing to chronic pain development. Here, we investigate the effect of TSPO ligand Etifoxine, on the development of chronic pain and motor dysfunction following sciatic nerve injury. Mechanical and thermal sensitivity, as well as motor function, were measured in rats before and after sciatic nerve crush (SNC). Rats were treated with the Etifoxine (50 mg/kg, twice daily) for one week. At the end of the experiment, RT-PCR and immunohistochemistry (IHC) were performed to assess mitochondrial stress and neuroinflammation. Additionally, high-resolution respirometry (O2k) was used to evaluate mitochondrial function in the spinal cord following mitochondrial permeability transition pore (mPTP) induction by Ca2+. Etifoxine treatment post-SNC alleviated mechanical and thermal hypersensitivity, as well as motor dysfunction in rats. In addition, Etifoxine treatment modulates neuroinflammation and mitochondrial stress. Specifically, we found a significant reduction in microglia presence and the transcription of pro-inflammatory cytokines (TNFα, IL-6, IL-1β) in the DRG and spinal cord of the SNC/etifoxine-treated group. Furthermore, Etifoxine treatment prevent the decline in mitochondrial respiration, including non-phosphorylation, ATP-linked respiration, and maximal respiration, after mPTP induction by Ca2+. Our findings suggest that TSPO-ligand Etifoxine protects against motor dysfunction and the development of chronic pain by reducing neuroinflammation and apoptosis in the DRG and spinal cord. Importantly, the beneficial effects of TSPO-ligands are reflected in the restoration of the mitochondrial function under challenging conditions.

Utilizing engineered extracellular vesicles as delivery vectors in the management of ischemic stroke: a special outlook on mitochondrial delivery

Ischemic stroke is a secondary cause of mortality worldwide, imposing considerable medical and economic burdens on society. Extracellular vesicles, serving as natural nano-carriers for drug delivery, exhibit excellent biocompatibility in vivo and have significant advantages in the management of ischemic stroke. However, the uncertain distribution and rapid clearance of extracellular vesicles impede their delivery efficiency. By utilizing membrane decoration or by encapsulating therapeutic cargo within extracellular vesicles, their delivery efficacy may be greatly improved. Furthermore, previous studies have indicated that microvesicles, a subset of large-sized extracellular vesicles, can transport mitochondria to neighboring cells, thereby aiding in the restoration of mitochondrial function post-ischemic stroke. Small extracellular vesicles have also demonstrated the capability to transfer mitochondrial components, such as proteins or deoxyribonucleic acid, or their sub-components, for extracellular vesicle-based ischemic stroke therapy. In this review, we undertake a comparative analysis of the isolation techniques employed for extracellular vesicles and present an overview of the current dominant extracellular vesicle modification methodologies. Given the complex facets of treating ischemic stroke, we also delineate various extracellular vesicle modification approaches which are suited to different facets of the treatment process. Moreover, given the burgeoning interest in mitochondrial delivery, we delved into the feasibility and existing research findings on the transportation of mitochondrial fractions or intact mitochondria through small extracellular vesicles and microvesicles to offer a fresh perspective on ischemic stroke therapy.

SIRT5-mediated desuccinylation prevents mitochondrial dysfunction in alveolar epithelial cells senescence and pulmonary fibrosis

Senescence of alveolar epithelial cells (AEC) is a key event in the onset and progression of Idiopathic pulmonary fibrosis (IPF). The pathogenic mechanisms that underlie the effects of AEC senescence remain largely unexplained. Some age-related diseases have an etiology linked to mitochondrial dysfunction induced by excessive lysine succinylation (Ksucc). SIRT5 can remove excessive Ksucc levels to maintain mitochondrial homeostasis. Therefore, this study aimed to determine the effects of SIRT5-mediated de-Ksucc on mitochondrial function and pulmonary fibrosis after AEC senescence. We found AEC in the lungs derived from IPF patients exhibit a marked accumulation of dysmorphic and dysfunctional mitochondria and excessive Ksucc levels. These mitochondrial abnormalities in AEC of normal mice with advancing age were associated with the downregulation of SIRT5. Increased SIRT5 expression by LV-SIRT5pcDNA in senescent AEC sustains mitochondrial integrity and reduces fibrotic effects of AEC senescence in established bleomycin (BLM)-aging mouse model. The level of ITGB1 K238 was upregulation in senescent AEC, LV-SIRT5pcDNA down-regulates the Ksucc level of ITGB1 K238 blocking the activation of ITGB1/STAT3 signaling pathway associated pulmonary fibrosis. Collectively, our findings indicate excessive lysine succinylation (hyperKsucc) is a fundamental basis for mitochondrial dysfunction in pulmonary fibrosis induced by the AEC senescence and SIRT5 alleviates AEC senescence by stabilizing the mitochondrial function.

Exomeres and supermeres: Current advances and perspectives

Recent studies have revealed a great diversity and complexity in extracellular vesicles and particles (EVPs). The developments in techniques and the growing awareness of the particle heterogeneity have spurred active research on new particle subsets. Latest discoveries highlighted unique features and roles of non-vesicular extracellular nanoparticles (NVEPs) as promising biomarkers and targets for diseases. These nanoparticles are distinct from extracellular vesicles (EVs) in terms of their smaller particle sizes and lack of a bilayer membrane structure and they are enriched with diverse bioactive molecules particularly proteins and RNAs, which are widely reported to be delivered and packaged in exosomes. This review is focused on the two recently identified membraneless NVEPs, exomeres and supermeres, to provide an overview of their biogenesis and contents, particularly those bioactive substances linked to their bio-properties. This review also explains the concepts and characteristics of these nanoparticles, to compare them with other EVPs, especially EVs, as well as to discuss their isolation and identification methods, research interests, potential clinical applications and open questions.

Involvement of the weak metabolic function in cardiovascular toxicity induced by idebenone in zebrafish

Idebenone (IDE) is a commonly used psychotropic drug in the clinic. However, the cardiovascular toxicity of IDE has not been reported previously. Therefore, we evaluated the safety of IDE and preliminarily elucidated the mechanism of cardiovascular toxicity induced by IDE using zebrafish as the model organism. In this study, wild-type AB zebrafish, and transgenic zebrafish Tg(cmcl2:EGFP) with green fluorescence-labelled cardiomyocytes were used as the research objects. We evaluated the effects of IDE on the sinus venosus-bulbus arteriosus (SV-BA) distance, ejection fraction, ventricular short-axis shortening rate, blood flow rate, and the staining area and intensity of cardiac erythrocytes. The toxic mechanism of IDE was elucidated using transcriptomics and Quantitative real-time PCR (qRT-PCR). We found that high concentrations of IDE could cause acute poisoning of some zebrafish within a short period (6 h), mainly characterized by severe cardiac venous stasis. IDE decreased the blood flow and reduced the red blood cell stained area in the heart region of some zebrafish. The results of transcriptome analysis and qRT-PCR showed that the expression of genes related to drug metabolism and lipid metabolism was significantly down-regulated in zebrafish with IDE-induced cardiovascular toxicity. We believe that IDE may be more likely to cause acute cardiovascular toxicity in organisms with weak metabolic enzyme function. The present study investigated the mechanism of the toxic effects of IDE using a zebrafish model and laid the foundation for a more comprehensive understanding of the cardiovascular toxicity of IDE.

The protective effect of curcumin on the diabetic uterus: Quantitative and qualitative evaluation

BACKGROUND

The objective of this study was to examine the impact of diabetes on the rat uterus and to assess the potential therapeutic benefits of curcumin in a diabetic uterus.

MATERIALS AND METHODS

A total of thirty-eight female Wistar albino rats were randomly assigned to seven experimental groups. The control group (Cont) was not subjected to any treatment. The sham group (Sham) was administered corn oil, while the curcumin group (Curc) received 30 mg/kg curcumin. A single dose of 50 mg/kg streptozotocin (STZ) was administered to induce experimental diabetes. The diabetic animals were then divided into four groups: a group with diabetes mellitus (DM), a group administered curcumin after seven days of diabetes induced (DC1) and 21 days (DC2) after the onset of diabetes, and a group that received curcumin simultaneously with STZ (DC3). The Cavalieri's method was used to estimate the volume ratios of the uterine epithelium, layers, and blood vessels.

RESULTS

The volume ratio of the myometrium was observed to be higher in the DC2 group than in the Cont and DM groups. Conversely, the endometrial volume ratio was found to be lower in the DC2 group than in the Cont group. The cell borders and basement membranes of the epithelial and gland cells were well preserved in the curcumin treatment groups, despite the obvious damage observed in the DM group. Similar findings were also observed in the electron microscopic sections, with collagen fibers, which were arranged in thick bands in the DM group and were unable to maintain their ultrastructure, were well organized in the DC1, DC2, and DC3.

CONCLUSION

Considering that it improves the endometrial structure and reduces degeneration in the surface and gland epithelium, it can be said that curcumin is an effective agent in reducing and preventing complications associated with DM in the uterus.

Water intake, hydration, and weight management: the glass is half-full!

The lack of practical and effective strategies to manage hunger and adhere to a weight management intervention represents a critical barrier to the weight management field. In proof-of-concept studies, we demonstrated that premeal water consumption (500 ml) acutely reduced perceived hunger and meal energy intake among middle-aged and older adults, and that premeal water consumption (500 ml, 3 times per day) increased the amount of weight lost after 12 weeks among middle-aged and older adults with overweight or obesity. However, water consumption may be important for weight management regardless of when it is consumed. This presentation summary addresses what is currently known about water intake, hydration status, and weight control. Findings from three recent systematic reviews focused on water intake and weight control are described. Potential mechanisms by which water consumption could impact appetite and hypocaloric diet adherence are discussed, and ongoing research on this topic is described.