Role of mitophagy in spinal cord ischemia-reperfusion injury

Spinal cord ischemia-reperfusion injury, a severe form of spinal cord damage, can lead to sensory and motor dysfunction. This injury often occurs after traumatic events, spinal cord surgeries, or thoracoabdominal aortic surgeries. The unpredictable nature of this condition, combined with limited treatment options, poses a significant burden on patients, their families, and society. Spinal cord ischemia-reperfusion injury leads to reduced neuronal regenerative capacity and complex pathological processes. In contrast, mitophagy is crucial for degrading damaged mitochondria, thereby supporting neuronal metabolism and energy supply. However, while moderate mitophagy can be beneficial in the context of spinal cord ischemia-reperfusion injury, excessive mitophagy may be detrimental. Therefore, this review aims to investigate the potential mechanisms and regulators of mitophagy involved in the pathological processes of spinal cord ischemia-reperfusion injury. The goal is to provide a comprehensive understanding of recent advancements in mitophagy related to spinal cord ischemia-reperfusion injury and clarify its potential clinical applications.

Stress granules: Guardians of cellular health and triggers of disease

Stress granules are membraneless organelles that serve as a protective cellular response to external stressors by sequestering non-translating messenger RNAs (mRNAs) and regulating protein synthesis. Stress granules formation mechanism is conserved across species, from yeast to mammals, and they play a critical role in minimizing cellular damage during stress. Composed of heterogeneous ribonucleoprotein complexes, stress granules are enriched not only in mRNAs but also in noncoding RNAs and various proteins, including translation initiation factors and RNA-binding proteins. Genetic mutations affecting stress granule assembly and disassembly can lead to abnormal stress granule accumulation, contributing to the progression of several diseases. Recent research indicates that stress granule dynamics are pivotal in determining their physiological and pathological functions, with acute stress granule formation offering protection and chronic stress granule accumulation being detrimental. This review focuses on the multifaceted roles of stress granules under diverse physiological conditions, such as regulation of mRNA transport, mRNA translation, apoptosis, germ cell development, phase separation processes that govern stress granule formation, and their emerging implications in pathophysiological scenarios, such as viral infections, cancer, neurodevelopmental disorders, neurodegeneration, and neuronal trauma.

Tryptophan metabolism and ischemic stroke: An intricate balance

Ischemic stroke, which is characterized by hypoxia and ischemia, triggers a cascade of injury responses, including neurotoxicity, inflammation, oxidative stress, disruption of the blood-brain barrier, and neuronal death. In this context, tryptophan metabolites and enzymes, which are synthesized through the kynurenine and 5-hydroxytryptamine pathways, play dual roles. The delicate balance between neurotoxic and neuroprotective substances is a crucial factor influencing the progression of ischemic stroke. Neuroprotective metabolites, such as kynurenic acid, exert their effects through various mechanisms, including competitive blockade of N-methyl-D-aspartate receptors, modulation of α7 nicotinic acetylcholine receptors, and scavenging of reactive oxygen species. In contrast, neurotoxic substances such as quinolinic acid can hinder the development of vascular glucose transporter proteins, induce neurotoxicity mediated by reactive oxygen species, and disrupt mitochondrial function. Additionally, the enzymes involved in tryptophan metabolism play major roles in these processes. Indoleamine 2,3-dioxygenase in the kynurenine pathway and tryptophan hydroxylase in the 5-hydroxytryptamine pathway influence neuroinflammation and brain homeostasis. Consequently, the metabolites generated through tryptophan metabolism have substantial effects on the development and progression of ischemic stroke. Stroke treatment aims to restore the balance of various metabolite levels; however, precise regulation of tryptophan metabolism within the central nervous system remains a major challenge for the treatment of ischemic stroke. Therefore, this review aimed to elucidate the complex interactions between tryptophan metabolites and enzymes in ischemic stroke and develop targeted therapies that can restore the delicate balance between neurotoxicity and neuroprotection.

Perinuclear organelle trauma at the nexus of cardiomyopathy pathogenesis arising from loss of function LMNA mutation

Over the past 25 years, nuclear envelope (NE) perturbations have been reported in various experimental models with mutations in the LMNA gene. Although the hypothesis that NE perturbations from LMNA mutations are a fundamental feature of striated muscle damage has garnered wide acceptance, the molecular sequalae provoked by the NE damage and how they underlie disease pathogenesis such as cardiomyopathy (LMNA cardiomyopathy) remain poorly understood. We recently shed light on one such consequence, by employing a cardiomyocyte-specific Lmna deletion in vivo in the adult heart. We observed extensive NE perturbations prior to cardiac function deterioration with collateral damage in the perinuclear space. The Golgi is particularly affected, leading to cytoprotective stress responses that are likely disrupted by the progressive deterioration of the Golgi itself. In this review, we discuss the etiology of LMNA cardiomyopathy with perinuclear 'organelle trauma' as the nexus between NE damage and disease pathogenesis.

Preclinical development of ozuriftamab vedotin (BA3021), a novel ROR2-specific conditionally active biologic antibody-drug conjugate

Receptor tyrosine kinase-like orphan receptor (ROR2) has been identified as a highly relevant tumor-associated antigen in a variety of cancer indications of high unmet medical need, including melanoma, renal cell carcinoma, osteosarcoma, gastrointestinal stromal tumor, colorectal cancer, pancreatic ductal adenocarcinoma, and non-small cell lung cancer. Overexpression of ROR2 often correlates with advanced disease or poor prognosis, making it an attractive target for cancer therapy. We developed a novel, conditionally active biologic (CAB) antibody-drug conjugate (ADC), ozuriftamab vedotin (BA3021), which binds to ROR2 only in the acidic tumor microenvironment. In healthy tissue, binding to ROR2 is greatly reduced by a novel selection mechanism using physiological chemicals as protein-associated chemical switches (PaCS). The CAB anti-ROR2 ADC displays the anticipated binding properties and mediates potent lysis of ROR2-positive cancer cell lines. In vivo, BA3021 has potent and durable antitumor activity in human cancer xenograft mouse models, including patient-derived xenograft models. In non-human primates, BA3021 was well tolerated at doses of up to 10 mg/kg and showed excellent stability in vivo. These preclinical results indicate that CAB anti-ROR2 ADC is efficacious and well tolerated and may be a promising treatment for cancer patients with ROR2-expressing tumors.

Acetaldehyde-driven mRNA methylation and expression changes in ethanol-metabolizing enzyme genes

This study examines how the alcohol metabolite acetaldehyde modulates mRNA methylation and expression of ethanol-metabolizing genes, uncovering its epigenetic role in ethanol metabolism. Using neuron-like (SH-SY5Y) and non-neuronal (SW620) cellular models, we examined the effects of chronic intermittent acetaldehyde (CIA) exposure and subsequent withdrawal (CIA+WD) on global RNA m6A modifications and the methylation and expression of three brain ethanol-metabolizing genes: CAT (catalase), CYP2E1 (cytochrome P450 2E1), and ALDH2 (aldehyde dehydrogenase 2). A 3-week CIA exposure, with or without 24-hour withdrawal, did not significantly alter global m6A methylation levels in either cell line. However, acetaldehyde exposure/withdrawal induced hypermethylation at the mRNA stop codon regions of ALDH2 (CIA: p = 0.002; CIA+WD: p = 0.055) and CAT (CIA: p = 0.077; CIA+WD: p = 0.036) in SH-SY5Y cells, but not in SW620 cells. Furthermore, ALDH2 mRNA expression was significantly upregulated in both cell types following exposure (SH-SY5Y: p = 0.073 [CIA] and 0.00002 [CIA+WD]; SW620: p = 0.0009 [CIA] and 0.00008 [CIA+WD]). In contrast, CYP2E1 mRNA methylation and the expression of CYP2E1 and CAT remained unchanged. These findings highlight the cell-specific epigenetic effects of acetaldehyde, particularly its role in modulating mRNA methylation and expression of ALDH2, a key enzyme in alcohol metabolism.

The role and function of lncRNA in ageing-associated liver diseases

Liver diseases are a significant global health issue, characterized by elevated levels of disorder and death. The substantial impact of ageing on liver diseases and their prognosis is evident. Multiple processes are involved in the ageing process, which ultimately leads to functional deterioration of this organ. The process of liver ageing not only renders the liver more susceptible to diseases but also compromises the integrity of other organs due to the liver's critical function in metabolism regulation. A growing body of research suggests that long non-coding RNAs (lncRNAs) play a significant role in the majority of pathophysiological pathways. They regulate gene expression through a variety of interactions with microRNAs (miRNAs), messenger RNAs (mRNAs), DNA, or proteins. LncRNAs exert a major influence on the progression of age-related liver diseases through the regulation of cell proliferation, necrosis, apoptosis, senescence, and metabolic reprogramming. A concise overview of the current understanding of lncRNAs and their potential impact on the development of age-related liver diseases will be provided in this mini-review.

Nuclear envelope and chromatin choreography direct cellular differentiation

The nuclear envelope plays an indispensable role in the spatiotemporal organization of chromatin and transcriptional regulation during the intricate process of cell differentiation. This review outlines the distinct regulatory networks between nuclear envelope proteins, transcription factors and epigenetic modifications in controlling the expression of cell lineage-specific genes during differentiation. Nuclear lamina with its associated nuclear envelope proteins organize heterochromatin via Lamina-Associated Domains (LADs), proximal to the nuclear periphery. Since nuclear lamina is mechanosensitive, we critically examine the impact of extracellular forces on differentiation outcomes. The nuclear envelope is spanned by nuclear pore complexes which, in addition to their central role in transport, are associated with chromatin organization. Furthermore, mutations in the nuclear envelope proteins disrupt differentiation, resulting in developmental disorders. Investigating the underlying nuclear envelope controlled regulatory mechanisms of chromatin remodelling during lineage commitment will accelerate our fundamental understanding of developmental biology and regenerative medicine.

DNA damage in prepared semen is negatively associated with semen quality and fertilisation rate in assisted reproduction technology (ART) treatment

Sperm DNA contains strand breaks and base damage that can potentially affect reproductive health. This study aims to determine to what extent sperm DNA integrity and alkylation is associated with semen quality and assisted reproduction technology (ART) treatment outcomes, in particular fertilisation and cleavage rates. Male partners of couples attending for infertility treatment were recruited. DNA integrity (% tail DNA, sperm with either low (LDD) or high (HDD) damage levels) was measured by a neutral Comet assay and N7-methyldeoxyguanosine (N7-MedG) DNA levels by an immunoslotblot in sperm prepared by density gradient centrifugation. Associations between DNA damage, semen quality and ART treatment outcomes were assessed. N7-MedG levels were lower and the proportion of LDD sperm higher in prepared than in neat sperm samples. The proportion of HDD sperm and % tail DNA were significantly negatively associated and the proportion of LDD sperm positively associated with semen quality. Fertilisation, but not cleavage, rate nor live birth, was significantly negatively associated with N7-MedG levels, the proportion of HDD sperm and % tail DNA and was positively associated with the proportion of LDD sperm. These results confirm that DNA damage, even in prepared sperm, is associated with adverse semen quality and suggest that sperm DNA damage affects the early stages of embryo formation.

Flavonoids from Polypodium hastatum as neuroprotective agents attenuate cerebral ischemia/reperfusion injury in vitro and in vivo via activating Nrf2

OBJECTIVES

Cerebral ischemic stroke is a leading cause of death worldwide. Though timely reperfusion reduces the infarction size, it exacerbates neuronal apoptosis due to oxidative stress. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor regulating the expression of antioxidant enzymes. Activating Nrf2 gives a therapeutic approach to ischemic stroke.

METHODS

Herein we explored flavonoids identified from Polypodium hastatum as Nrf2 activators and their protective effects on PC12 cells injured by oxygen and glucose deprivation/restoration (OGD/R) as well as middle cerebral artery occlusion (MCAO) mice.

RESULTS

The results showed among these flavonoids, AAKR significantly improved the survival of PC12 cells induced by OGD/R and activated Nrf2 in a Keap1-dependent manner. Further investigations have disclosed AAKR attenuated oxidative stress, mitochondrial dysfunction and following apoptosis resulting from OGD/R. Meanwhile, activation of Nrf2 by AAKR was involved in the protective effects. Finally, it was found that AAKR could protect MCAO mice brains against ischemia/reperfusion injury via activating Nrf2.

DISCUSSION

This investigation could provide lead compounds for the discovery of novel Nrf2 activators targeting ischemia/reperfusion injury.

Rotenone inhibited osteosarcoma metastasis by modulating ZO-2 expression and location via the ROS/Ca2+/AMPK pathway

BACKGROUND

Pulmonary metastases in osteosarcoma (OS) are associated with a poor prognosis. Rotenone has shown anti-cancer activity. However, its effects on metastasis and the underlying mechanisms remain unknown. This study investigated the potential use of Rotenone for OS treatment.

METHODS

The effect of Rotenone and ROS/Ca2+/AMPK/ZO-2 pathway on metastasis and EMT was evaluated by Western blot, Transwell and Wound healing. Flow cytometer was employed to measure the intracellular Ros and Ca2+ levels. The subcellular location of ZO-2 was detected by IF, interaction between AMPK and ZO-2 were examined by Co-IP. Then, subcutaneous tumor and metastasis models were used to evaluate the function of Rotenone in OS metastasis.

RESULTS

Rotenone-induced ROS led to increased intracellular Ca2+, which promoted the EMT of OS cells through activation of AMPK and ZO-2 nuclear translocation. Inhibition of ROS production decreased intracellular Ca2+, restraining AMPK activity. Knock-down of ZO-2 significantly suppressed the anti-metastasis effects of Rotenone in OS cells. Moreover, Rotenone elevated p-AMPK and ZO-2 expression but inhibited EMT and lung metastasis in vivo.Conclusion These results provide evidence supporting an anti-metastatic effect of Rotenone. These findings support the use of Rotenone in the prevention of OS metastasis.

Development and application of an uncapped mRNA platform

BACKGROUND

A novel uncapped mRNA platform was developed.

METHODS

Five lipid nanoparticle (LNP)-encapsulated mRNA constructs were made to evaluate several aspects of our platform, including transfection efficiency and durability in vitro and in vivo and the activation of humoral and cellular immunity in several animal models. The constructs were eGFP-mRNA-LNP (for enhanced green fluorescence mRNA), Fluc-mRNA-LNP (for firefly luciferase mRNA), SδT-mRNA-LNP (for Delta strain SARS-CoV-2 spike protein trimer mRNA), gDED-mRNA-LNP (for truncated glycoprotein D mRNA coding ectodomain from herpes simplex virus type 2 (HSV2)) and gDFR-mRNA-LNP (for truncated HSV2 glycoprotein D mRNA coding amino acids 1-400).

RESULTS

Quantifiable target protein expression was achieved in vitro and in vivo with eGFP- and Fluc-mRNA-LNP. SδT-mRNA-LNP, gDED-mRNA-LNP and gDFR-mRNA-LNP induced both humoral and cellular immune responses comparable to those obtained by previously reported capped mRNA-LNP constructs. Notably, SδT-mRNA-LNP elicited neutralizing antibodies in hamsters against the Omicron and Delta strains. Additionally, gDED-mRNA-LNP and gDFR-mRNA-LNP induced potent neutralizing antibodies in rabbits and mice. The mRNA constructs with uridine triphosphate (UTP) outperformed those with N1-methylpseudouridine triphosphate (N1mψTP) in the induction of antibodies via SδT-mRNA-LNP.

CONCLUSIONS

Our uncapped, process-simplified and economical mRNA platform may have broad utility in vaccines and protein replacement drugs.KEY MESSAGESThe mRNA platform described in our paper uses internal ribosome entry site (IRES) (Rapid, Amplified, Capless and Economical, RACE; Register as BH-RACE platform) instead of caps and uridine triphosphate (UTP) instead of N1-methylpseudouridine triphosphate (N1mψTP) to synthesize mRNA.Through the self-developed packaging instrument and lipid nanoparticle (LNP) delivery system, mRNA can be expressed in cells more efficiently, quickly and economically.Particularly exciting is that potent neutralizing antibodies against Delta and Omicron real viruses were induced with the new coronavirus S protein mRNA vaccine from the BH-RACE platform.

The search for a TNBC vaccine: the guardian vaccine

Nearly 20 million people are diagnosed with cancer each year with breast cancer being the most common among women. Triple negative breast cancer (TNBC), defined by its no/low expression of ER and PR and lack of amplification of HER2, makes up 15-20% of all breast cancer cases. While patients overall have a higher response to chemotherapy, this subgroup is associated with the lowest survival rate indicating significant clinical and molecular heterogeneity demanding alternate treatment options. Therefore, new therapies have been explored, with a large focus on utilizing the immune system. A whole host of immunotherapies have been studied including immune checkpoint inhibitors, now standard of care for eligible patients, and possibly the most exciting and promising is that of a TNBC vaccine. While currently there are no approved TNBC vaccines, this review highlights many promising studies and points to an antigen, p53, which we believe is highly relevant for TNBC.

Relationship between the expression levels of myogenic regulatory factor genes and carcass characteristics in Kivircik and Hungarian Merino lambs

This study aimed to investigate the expression profiles of the myogenic regulatory genes MYOD1, MYOG, MYF5, MYF6, and MSTN in longissimus dorsi muscle, as well as the correlation of the expression levels of these genes with carcass characteristics and growth performance in the Kivircik and Hungarian Merino sheep breeds. The expression levels of the MYF5, MYF6, and MYOG genes were found to be significantly correlated with the rib proportion, the expression level of the MYOG gene was identified as being the main determinant of variations in the rib proportion in the Kivircik lambs. The regression analysis results revealed that the expression levels of the MYF5 and MSTN genes played an essential role in determining the cold carcass dressing percentage in Hungarian Merino lambs. Further, as a result of the regression analysis, the model including the expression level of the MYF6 gene demonstrated that this gene could be responsible for 36.4% of the differences observed in cold carcass weight. In conclusion, the findings of this study suggest that the expression levels of the MYF5, MYF6, and MYOG genes were associated with various carcass traits, particularly in the Kivircik breed, and these genes hold potential as markers for enhancing breed productivity.

Daurisoline inhibits glycolysis of lung cancer by targeting the AKT-HK2 axis

Lung cancer, one of the most prevalent tumors, remains a clinical challenge with a poor five-year survival rate. Daurisoline, a bis-benzylisoquinoline alkaloid derived from the traditional Chinese herb Menispermum dauricum, is known to suppress tumor growth effectively. However, its precise mechanism of action remains unclear. In this study, we demonstrate that Daurisoline targets glycolysis and reduces the protein level of HK2, thereby inhibiting lung cancer progression. Mechanistic investigations reveal that Daurisoline directly binds to AKT and antagonizes the AKT-GSK3β-c-Myc-HK2 signaling axis. Furthermore, in an animal model, we validate the in vivo anti-tumor effect of Daurisoline without any observable side effects. Overall, our findings suggest that Daurisoline holds potential as an anti-tumor agent through its targeting of glycolysis.

Construction of a novel radioresistance-related signature for prediction of prognosis, immune microenvironment and anti-tumour drug sensitivity in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is a fatal disease, and radioresistance is an important factor leading to treatment failure and disease progression. The objective of this research was to detect radioresistance-related genes (RRRGs) with prognostic value in NSCLC.

METHODS

The weighted gene coexpression network analysis (WGCNA) and differentially expressed genes (DEGs) analysis were performed to identify RRRGs using expression profiles from TCGA and GEO databases. The least absolute shrinkage and selection operator (LASSO) regression and random survival forest (RSF) were used to screen for prognostically relevant RRRGs. Multivariate Cox regression was used to construct a risk score model. Then, Immune landscape and drug sensitivity were evaluated. The biological functions exerted by the key gene LBH were verified by in vitro experiments.

RESULTS

Ninety-nine RRRGs were screened by intersecting the results of DEGs and WGCNA, then 11 hub RRRGs associated with survival were identified using machine learning algorithms (LASSO and RSF). Subsequently, an eight-gene (APOBEC3B, DOCK4, IER5L, LBH, LY6K, RERG, RMDN2 and TSPAN2) risk score model was established and demonstrated to be an independent prognostic factor in NSCLC on the basis of Cox regression analysis. The immune landscape and sensitivity to anti-tumour drugs showed significant disparities between patients categorized into different risk score subgroups. In vitro experiments indicated that overexpression of LBH enhanced the radiosensitivity of A549 cells, and knockdown LBH reversed the cytotoxicity induced by X-rays.

CONCLUSION

Our study developed an eight-gene risk score model with potential clinical value that can be adopted for choice of drug treatment and prognostic prediction. Its clinical routine use may assist clinicians in selecting more rational practices for individuals, which is important for improving the prognosis of NSCLC patients. These findings also provide references for the development of potential therapeutic targets.

tRNA modifications: greasing the wheels of translation and beyond

Transfer RNA (tRNA) is one of the most abundant RNA types in cells, acting as an adaptor to bridge the genetic information in mRNAs with the amino acid sequence in proteins. Both tRNAs and small fragments processed from them play many nonconventional roles in addition to translation. tRNA molecules undergo various types of chemical modifications to ensure the accuracy and efficiency of translation and regulate their diverse functions beyond translation. In this review, we discuss the biogenesis and molecular mechanisms of tRNA modifications, including major tRNA modifications, writer enzymes, and their dynamic regulation. We also summarize the state-of-the-art technologies for measuring tRNA modification, with a particular focus on 2'-O-methylation (Nm), and discuss their limitations and remaining challenges. Finally, we highlight recent discoveries linking dysregulation of tRNA modifications with genetic diseases.

ELAV/Hu RNA-binding protein family: key regulators in neurological disorders, cancer, and other diseases

The ELAV/Hu family represents a crucial group of RNA-binding proteins predominantly expressed in neurons, playing significant roles in mRNA transcription and translation. These proteins bind to AU-rich elements in transcripts to regulate the expression of cytokines, growth factors, and the development and maintenance of neurons. Elav-like RNA-binding proteins exhibit remarkable molecular weight conservation across different species, highlighting their evolutionary conservation. Although these proteins are widely expressed in the nervous system and other cell types, variations in the DNA sequences of the four Elav proteins contribute to their distinct roles in neurological disorders, cancer, and other Diseases . Elavl1, a ubiquitously expressed family member, is integral to processes such as cell growth, ageing, tumorigenesis, and inflammatory diseases. Elavl2, primarily expressed in the nervous and reproductive systems, is critical for central nervous system and retinal development; its dysregulation has been implicated in neurodevelopmental disorders such as autism. Both Elavl3 and Elavl4 are restricted to the nervous system and are involved in neuronal differentiation and excitability. Elavl3 is essential for cerebellar function and has been associated with epilepsy, while Elavl4 is linked to neurodegenerative diseases, including Parkinson's and Alzheimer's diseases. This paper provides a comprehensive review of the ELAV/Hu family's role in nervous system development, neurological disorders, cancer, and other diseases.

The Hog1-Nmd5 signaling pathway regulates asexual development, lipid metabolism, stress response, trap morphogenesis, and secondary metabolism of Arthrobotrys oligospora

The high-osmolarity glycerol (HOG) signalling pathway, comprising Ste11/Ssk2/Ssk22 (MAPKKK), Pbs2 (MAPKK), and Hog1 (MAPK), is an important and conserved pathway in fungi. However, the functions and downstream regulatory factors of Hog1 in nematode-trapping (NT) fungi remain poorly understood. Here, three proteins (AoNmd5, AoPyp1, and AoPtp) interacting with Hog1 were screened in a representative NT fungus Arthrobotrys oligospora using yeast screening library and verified using yeast two-hybrid (Y2H) assay. The function of AoNmd5 was furtherly characterized by phenotypic comparison, staining technique, and multi-omics analyses. AoNmd5 was essential for vegetative growth, conidial development, trap morphogenesis, and nematode predation ability. In addition, AoNmd5 played crucial roles in endocytosis, lipid metabolism, reactive oxygen species, stress response, autophagy, and other metabolic processes. Furthermore, we constructed an AoNmd5 interaction network based on transcriptomic analysis and Y2H, revealing its significant role in the respiratory chain and redox processes as well as its interaction with the small GTPase Ran1, which mediates Hog1 nucleocytoplasmic shuttling. These findings suggest that the Hog1-Nmd5 signalling pathway has pleiotropic roles in A. oligospora. This study deepens our understanding of the HOG pathway and its interaction with importins in NT fungi.

Qing-Xin-Jie-Yu Granule attenuates myocardial infarction-induced inflammatory response by regulating the MK2/TTP pathway

CONTEXT

Qing-Xin-Jie-Yu Granule (QXJYG) has shown promise in the treatment of myocardial infarction. However, the mechanism of action of QXJYG underlying its anti-inflammation remain unknown.

OBJECTIVE

The study aimed to evaluate the effectiveness and mechanism of QXJYG in a mouse model of myocardial infarction and hypoxia-induced H9C2 cells.

MATERIALS AND METHODS

Myocardial infarction was induced in mice via left anterior descending coronary artery ligation, and hypoxia-induced H9C2 cells was served as the in vitro model. The cardiac function was evaluated by echocardiography, while myocardial tissue pathology was examined using HE and Masson's trichrome staining. Changes in serum markers of cardiac injury were measured using ELISA kits. The levels of inflammatory cytokines in both the serum and cardiac tissue were quantified using the Bio-Plex Pro Mouse Chemokine assay, and hypoxia-induced inflammatory factors in H9C2 cells were assessed by RT-qPCR. Additionally, western blot analysis was conducted to evaluate the expression of proteins related to the MK2/TTP signaling pathway both in vivo and in vitro experiments.

RESULTS

QXJYG significantly enhanced cardiac function in mice with myocardial infarction, as evidenced by improved myocardial tissue structure, reduced collagen fiber deposition, and lowered serum levels of creatine kinase isoenzyme MB (CK-MB), cardiac Troponin T (cTnT), and brain Natriuretic Peptide (BNP). QXJYG may reduce the expression of inflammatory factors in both the heart and serum of myocardial infarction-induced mice and attenuate hypoxia-induced levels of inflammatory factors in cardiomyocytes by decreasing the ratio of p-MK2/MK2 and increasing the protein expression of TTP.

DISCUSSION AND CONCLUSIONS

QXJYG improved cardiac function and reduced injury, fibrosis, and inflammation after myocardial infarction, likely through modulation of the MK2/TTP signaling pathway.

Promoting collagen synthesis: a viable strategy to combat skin ageing

Skin ageing is a complex physiological process primarily characterised by the deepening of wrinkles and the sagging of the skin. Collagen is essential for maintaining skin elasticity and firmness. As skin ages, it experiences structural and functional changes in collagen, including a decrease in collagen synthesis and an increase in collagen hydrolysis. Thus, promoting collagen synthesis represents a practical strategy for mitigating skin ageing. This review systematically described the functions, classifications and biosynthesis process of collagen, as well as its role in skin ageing. Additionally, the major signalling pathways and targets associated with collagen synthesis were also discussed. More importantly, the review provided a detailed summary of natural products with collagen synthesis-promoting effects and highlighted small molecule compounds with potential anti-ageing activity, especially PPARδ agonists. The relevant content offers potential targets and lead compounds for the development of anti-skin ageing therapies.

Histone modifications in the regulation of erythropoiesis

INTRODUCTION

The pathogenesis of anemia and other erythroid dysphasia are mains poorly understood, primarily due to limited knowledge about the differentiation processes and regulatory mechanisms governing erythropoiesis. Erythropoiesis is a highly complex and precise biological process, that can be categorized into three distinct stages: early erythropoiesis, terminal erythroid differentiation, and reticulocyte maturation, and this complex process is tightly controlled by multiple regulatory factors. Emerging evidence highlights the crucial role of epigenetic modifications, particularly histone modifications, in regulating erythropoiesis. Methylation and acetylation are two common modification forms that affect genome accessibility by altering the state of chromatin, thereby regulating gene expression during erythropoiesis.

DISCUSSION

This review systematically examines the roles of histone methylation and acetylation, along with their respective regulatory enzymes, in regulating the development and differentiation of hematopoietic stem/progenitor cells (HSPCs) and erythroid progenitors. Furthermore, we discuss the involvement of these histone modifications in erythroid-specific developmental processes, including hemoglobin switching, chromatin condensation, and enucleation.Conclusions This review summarizes the current understanding of the role of histone modifications in erythropoiesis based on existing research, as a foundation for further research the mechanisms of epigenetic regulatory in erythropoiesis.

Staphylococcus warneri dampens SUMOylation and promotes intestinal inflammation

Gut bacteria play key roles in intestinal physiology, via the secretion of diversified bacterial effectors. Many of these effectors remodel the host proteome, either by altering transcription or by regulating protein post-translational modifications. SUMOylation, a ubiquitin-like post-translational modification playing key roles in intestinal physiology, is a target of gut bacteria. Mutualistic gut bacteria can promote SUMOylation, via the production of short- or branched-chain fatty acids (SCFA/BCFA). In contrast, several pathogenic bacteria were shown to dampen SUMOylation in order to promote infection. Here, we demonstrate that Staphylococcus warneri, a natural member of the human gut microbiota, decreases SUMOylation in intestinal cells. We identify that Warnericin RK, a hemolytic toxin secreted by S. warneri, targets key components of the host SUMOylation machinery, leading to the loss of SUMO-conjugated proteins. We further demonstrate that Warnericin RK promotes inflammation in intestinal and immune cells using both SUMO-dependent and SUMO-independent mechanisms. We finally show that Warnericin RK regulates the expression of genes involved in intestinal tight junctions. Together, these results highlight the diversity of mechanisms used by bacteria from the gut microbiota to manipulate host SUMOylation. They further highlight that changes in gut microbiota composition may impact intestinal inflammation, by altering the equilibrium between bacterial effectors promoting or dampening SUMOylation.

The critical role of ferroptosis in virus-associated hematologic malignancies and its potential value in antiviral-antitumor therapy

Epstein-Barr Virus (EBV), Kaposi's sarcoma-associated herpesvirus (KSHV), and human T-cell leukemia virus type 1 (HTLV-1) are key infectious agents linked to the development of various hematological malignancies, including Hodgkin's lymphoma, non-Hodgkin's lymphoma, and adult T-cell leukemia/lymphoma. This review highlights the critical knowledge gaps in understanding the role of ferroptosis, a novel form of cell death, in virus-related tumors. We focus on how ferroptosis influences the host cell response to these viral infections, revealing groundbreaking mechanisms by which the three viruses differentially regulate core pathways of ferroptosis, such as iron homeostasis, lipid peroxidation, and antioxidant systems, thereby promoting malignant transformation of host cells. Additionally, we explore the potential of antiviral drugs and ferroptosis modulators in the treatment of virus-associated hematological malignancies.

Interplay of replication timing, DNA repair, and translesion synthesis in UV mutagenesis in yeast

Replication timing during S-phase impacts mutation rates in yeast and human cancers; however, the exact mechanism involved remains unclear. Here, we analyze the impact of replication timing on UV mutagenesis in Saccharomyces cerevisiae. Our analysis indicates that UV mutations are enriched in early-replicating regions of the genome in wild-type cells, but in cells deficient in global genomic-nucleotide excision repair (GG-NER), mutations are enriched in late-replicating regions. Analysis of UV damage maps revealed that cyclobutane pyrimidine dimers are enriched in late-replicating regions, but this enrichment is almost entirely due to repetitive ribosomal DNA. Complex mutations typically associated with TLS activity are also elevated in late-replicating regions in GG-NER deficient cells. We propose that UV mutagenesis is higher in early-replicating regions in repair-competent cells because there is less time to repair the lesion prior to undergoing replication. However, in the absence of GG-NER, increased TLS activity promotes UV mutagenesis in late-replicating regions.

Engineering non-pathogenic bacteria for auto-transporter-driven secretion of functional interferon

In recent years, various strategies have been developed to enable the oral administration of protein-based drugs (biologics) with the aim of overcoming the degradation and inactivation of these drugs that can occur as they traverse the gastrointestinal tract (GIT). In this study, we investigated bacteria as a delivery vehicle for biologics, harnessing their ability to withstand the harsh gastric environment and deliver therapeutic drugs directly to the intestine. Specifically, we explored using the type 5 secretion system (T5SS) to secrete therapeutic cargoes under simulated gut conditions. Our research focused on EspC, a T5SS protein from enteropathogenic Escherichia coli, and its potential to secrete interferon-α (IFNα), a cytokine with immunomodulatory and antiviral properties widely used in the clinic. We demonstrated that EspC can facilitate the secretion of IFNα variant when expressed in nonpathogenic bacteria. Moreover, this EspC-secreted IFN was able to activate the JAK-STAT pathway, upregulate IFN-stimulated genes, and induce a robust antiviral response in cells. Collectively, these findings provide proof of concept supporting the utilization of the EspC protein as a novel delivery platform for protein-based therapeutics.

Advances in deciphering the mechanisms of salt tolerance in Maize

Maize (Zea mays L.) is a vital crop worldwide, serving as a cornerstone for food security, livestock feed, and biofuel production. However, its cultivation is increasingly jeopardized by environmental challenges, notably soil salinization, which severely constrains growth, yield, and quality. To combat salinity stress, maize employs an array of adaptive mechanisms, including enhanced antioxidant enzyme activity and modulated plant hormone levels, which work synergistically to maintain reactive oxygen species (ROS) balance and ion homeostasis. This review explores the intricate interactions among ROS, antioxidant systems, plant hormones, and ion regulation in maize under salt stress, providing a comprehensive understanding of the physiological and molecular basis of its tolerance. By elucidating these mechanisms, this study contributes to the development of salt-tolerant maize varieties and informs innovative strategies to sustain agricultural productivity under adverse environmental conditions, offering significant theoretical insights into plant stress biology and practical solutions for achieving sustainable agriculture amidst global climate challenges.

Comparative transcriptome analysis reveals abscisic acid-induced bHLH transcription factors involved in saikosaponin biosynthesis in Bupleurum chinense DC

Bupleurum chinense DC. a medicinal plant valued for saikosaponins (SSs) with antipyretic and hepatoprotective properties, faces constrained SS biosynthesis mediated by abscisic acid (ABA) during growth. Basic helix-loop-helix (bHLH) transcription factors (TFs) are hypothesized to participate in ABA signaling cascades, but their mechanistic role in SS regulation remains undefined. In this study, 20 differentially expressed BcbHLH genes were identified by transcriptomic profiling of ABA-induced hairy roots, with four MYC-family candidates (BcbHLH1-BcbHLH4) demonstrating ABA-responsive regulatory potential. ABA exposure (100 or 200 μmol/L, 24-72 h) induced dose-dependent SS reduction, while correlation analyses revealed coordinated expression between BcbHLH1-BcHMGR (r = 0.62) and BcbHLH4-BcBAS (r = 0.78), pinpointing these TFs as critical nodes in SS pathway modulation. Tissue-specific profiling showed predominant BcbHLH expression in stems and young leaves, with nuclear localization confirming their transcriptional regulatory organelles. BcbHLH3/4 exhibited transcriptional activation activity in the MYC_N domain, while molecular docking predicted 11th Arginine in the HLH domain as essential for G-box DNA binding. Collectively, our findings suggest that BcbHLH1-BcbHLH4 may serve as potential switches for fine-tuning ABA responsiveness in SS biosynthesis. Strategic manipulation of BcbHLH activity through genetic engineering approaches such as CRISPR-based editing or overexpression could alleviate ABA-mediated biosynthetic repression. Furthermore, precision engineering of the critical functional domain in BcbHLH could enhance promoter-binding activity to target genes and improve SS biosynthesis efficiency. These findings provide a reference framework for harnessing transcriptional regulators to optimize SS production in Bupleurum chinense DC.

The genetic basis of male and female infertility

This review provides a comprehensive overview of the genetic factors underlying male and female infertility. Infertility affects an estimated one in six couples worldwide, with both male and female factors contributing equally to its prevalence. Approximately, 50% of infertility cases are attributed to genetic causes. We explore three main categories of genetic causes: chromosomal abnormalities, monogenic disorders, and syndromic conditions. Chromosomal causes, including numerical and structural aberrations, are discussed with a focus on their impact on gametogenesis and reproductive outcomes. We review key monogenic causes of infertility, highlighting recent discoveries in genes critical for gonadal development, gametogenesis, and hormonal regulation. Syndromic conditions affecting fertility are examined, highlighting their impact on reproductive function. Throughout the review, we address the challenges in identifying genetic mechanisms of infertility, particularly focusing on the intricate processes involved in oogenesis and spermatogenesis. We also discuss how advancements in genetic testing, such as next-generation sequencing (NGS) and genome-wide association studies (GWAS), have significantly enhanced our understanding of idiopathic infertility and promise further insights in the future. We also discuss the clinical implications of genetic diagnoses, including the role of preimplantation genetic testing (PGT) and genetic counseling in reproductive medicine. This review synthesizes current knowledge on the genetic basis of infertility, providing a comprehensive overview of chromosomal, monogenic, and syndromic causes. It aims to offer readers a solid foundation for understanding the complex genetic factors underlying reproductive disorders.

Glucocorticoid receptor epigenetic activity in the heart

The glucocorticoid receptor (GR) is a critical nuclear receptor that regulates gene expression in diverse tissues, including the heart, where it plays a key role in maintaining cardiovascular health. GR signaling influences essential processes within cardiomyocytes, including hypertrophy, calcium handling, and metabolic balance, all of which are vital for proper cardiac function. Dysregulation of GR activity has been implicated in various cardiovascular diseases (CVDs), highlighting the potential of GR as a therapeutic target. Remarkably, recent insights into GR's epigenetic regulation and its interaction with circadian rhythms reveal opportunities to optimize therapeutic strategies by aligning glucocorticoid administration with circadian timing. In this review, we provide an overview of the glucocorticoid receptor's role in cardiac physiology, detailing its genomic and non-genomic pathways, interactions with epigenetic and circadian regulatory mechanisms, and implications for cardiovascular disease. By dissecting these molecular interactions, this review outlines the potential of epigenetically informed and circadian-timed interventions that could change the current paradigms of CVD treatments in favor of precise and effective therapies.

Pharmacological inhibition of SUMOylation with TAK-981 mimics genetic HypoSUMOylation in murine perigonadal white adipose tissue

Post-translational modification by the small ubiquitin-like modifier (SUMO) is essential for cellular differentiation and homeostasis. Here, we investigate the role of SUMOylation in adipose tissue development using TAK-981, a pharmacological inhibitor of SUMOylation. Administration of TAK-981 to mice resulted in significant defect in weight gain and adipocyte atrophy in perigonadal white adipose tissue (gWAT) depots. Gene expression analyses revealed a marked downregulation of adipogenic genes, including Pparg, Cebpa, and Fasn. Our data thus indicate that TAK-981 treatment impaired adipogenesis in gWAT, consistent with prior findings that SUMOylation supports transcriptional regulation of adipogenesis and lipid metabolism. We also found significant infiltration of immune cells and efferocytosis in gWAT. Our results thus indicate that SUMOylation inhibition using a small molecule phenocopies genetic hypoSUMOylation models, highlighting its critical role in maintaining adipocyte functionality and immune environment. These findings provide evidence that SUMOylation is essential for fat accumulation in vivo. Furthermore, given that TAK-981 is currently under clinical evaluation for the treatment of solid tumors, our results underscore the importance of considering the potential unintended effects of SUMOylation inhibition on adipose tissue in patients.

SIRT1/DNMT3B-mediated epigenetic gene silencing in response to phytoestrogens in mammary epithelial cells

We performed an integrated analysis of genome-wide DNA methylation and expression datasets in normal cells and healthy animals exposed to polyphenols with estrogenic activity (i.e. phytoestrogens). We identified that phytoestrogens target genes linked to disrupted cellular homeostasis, e.g. genes limiting DNA break repair (RNF169) or promoting ribosomal biogenesis (rDNA). Existing evidence suggests that DNA methylation may be governed by sirtuin 1 (SIRT1) deacetylase via interactions with DNA methylating enzymes, specifically DNMT3B. Since SIRT1 was reported to be regulated by phytoestrogens, we test whether phytoestrogens suppress genes related to disrupted homeostasis via SIRT1/DNMT3B-mediated transcriptional silencing. Human MCF10A mammary epithelial cells were treated with phytoestrogens, pterostilbene (PTS) or genistein (GEN), followed by analysis of cell growth, DNA methylation, gene expression, and SIRT1/DNMT3B binding. SIRT1 occupancy at the selected phytoestrogen-target genes, RNF169 and rDNA, was accompanied by consistent promoter hypermethylation and gene downregulation in response to GEN, but not PTS. GEN-mediated hypermethylation and SIRT1 binding were linked to a robust DNMT3B enrichment at RNF169 and rDNA promoters. This was not observed in cells exposed to PTS, suggesting a distinct mechanism of action. Although both SIRT1 and DNMT3B bind to RNF169 and rDNA promoters upon GEN, the two proteins do not co-occupy the regions. Depletion of SIRT1 abolishes GEN-mediated decrease in rDNA expression, suggesting SIRT1-dependent epigenetic suppression of rDNA by GEN. These findings enhance our understanding of the role of SIRT1-DNMT3B interplay in epigenetic mechanisms mediating the impact of phytoestrogens on cell biology and cellular homeostasis.

Nitric oxide: a gas transmitter in healthy and diseased skin

Numerous physiological processes in the human skin are mediated by nitric oxide, a gaseous signalling molecule. Almost every type of skin cell may produce nitric oxide, it is possible to generate nitric oxide without the need of enzymes. Nitric oxide plays a crucial role in regulating apoptosis, keratinocyte differentiation and proliferation, the protective properties of the epidermal barrier, and the structure and functions of the microcirculatory bed. Nitric oxide is involved in immunological and inflammatory responses, hair growth regulation, and wound healing processes. It mediates ultraviolet-induced processes such as erythema and edema development and participates in melanogenesis. Furthermore, the ability of nitric oxide to bind reactive oxygen species and prevent lipid peroxidation gives it antioxidant qualities. This coordinated action of nitric oxide on gene expression and membrane integrity effectively protects cells from ultraviolet A-induced apoptosis and necrosis. Furthermore, nitric oxide can be considered as a molecule that inhibits the development of cancer and photoaging. It directly harms microorganisms and indirectly activates the immune system, exhibiting antibacterial, antiviral, and antifungal qualities. Notably, nitric oxide is effective against antibiotics-resistant bacteria. All of the aforementioned findings suggest that nitric oxide is a gaseous mediator that can protect skin function.

In vivo antitumor activity of PHT-427 inhibitor-loaded polymeric nanoparticles in head and neck squamous cell carcinoma

Recent studies on head and neck squamous cell carcinoma (HNSCC) tumorigenesis have revealed several dysregulated molecular pathways. The phosphatidylinositol-3-kinase (PI3K) signaling pathway is frequently activated in HNSCC, making it an attractive target for therapies. PHT-427 is a dual inhibitor of PI3K and the mammalian target of AKT/PDK1. This study evaluates the anticancer efficacy of the inhibitor PHT-427 loaded into polymeric nanoparticles (NP) based on α-TOS (NP-427) administered by intratumoral injection into a hypopharyngeal squamous cell carcinoma (FaDu cells) heterotopic xenograft mouse model. The nanocarrier system, based on block copolymers of N-vinylpyrrolidone (VP) and a methacrylic derivative of α-TOS (MTOS), was synthesized, and PHT-427 was loaded into the delivery system. First, we evaluated the effect of NP-427 on tumor growth by measuring tumor volume, mouse weight, survival, and the development of tumor ulceration and necrosis. In addition, we measured PI3KCA/AKT/PDK1 gene expression, PI3KCA/AKT/PDK1 protein levels, Epidermal Growth Factor Receptor (EGFR), and angiogenesis in the tumor tissue. PHT-427 encapsulation increased drug efficacy and safety, as demonstrated by decreased tumor volume, reduced PI3K/AKT/PDK1 pathway expression, and improved antitumor activity and necrosis induction in the mouse xenograft model. EGFR and angiogenesis marker (Factor VIII) expression were significantly lower in the NP-427 group compared to other experimental groups. Administration of encapsulated PHT-427 at the tumor sites proves promising for HNSCC therapy.

Comprehensive analysis of eccDNA characteristics and associated genes expression in peripheral blood of ASLE and ISLE patients

To explore SLE staging markers, we analyzed eccDNA in plasma using circular sequencing, comparing healthy controls (HC), active SLE (ASLE), and inactive SLE (ISLE) patients. We found higher eccDNA levels and lower GC content in ASLE and ISLE compared to healthy controls, with a negative correlation between GC content and anti-daDNA, C3, and C4 levels in SLE and HC samples. Differential expression of exon-derived eccGenes in ASLE and ISLE suggests their role in SLE development, with KEGG analysis showing enrichment in SLE-related pathways for these differentially expressed genes. By protein-protein interactions network analysis we found 9 exon-derived eccGenes that were significantly differentially expressed and scored high in both ISLE-HC and ASLE-ISLE as diagnostic criteria for differentiating different disease stages of SLE. In conclusion, the present study reveals that eccDNA length GC content as well as chromosomal distribution in ASLE, ISLE and HC suggests that with eccDNA is associated with the creation of SLE, suggesting GC count of eccDNA as a diagnostic marker for systemic lupus erythematosus. Significant changes in the abundance of eccDNA-related genes from exons such as SOS1, GAD2, BCL11B, PPT1, and GCNT3 were observed in ISLE as compared to ASLE and HC groups and were significantly correlated with SLEDAI-2K. This suggests that these exon-derived eccGenes may play a role in the development and progression of the disease. Consequently, the abundance levels of these exon-derived eccGenes could potentially assist in distinguishing different stages of SLE, beyond a confirmed diagnosis, thus serving as possible biomarkers for the condition.

METTL14 and WTAP play a crucial role in the regulation of bovine preadipocyte differentiation

m6A methylation is the most common mRNA modification in mammals and plays a significant role in regulating various biological functions. Some studies have demonstrated that the methyltransferase METTL3 can promote adipogenesis. However, the regulatory mechanisms of METTL14 and WTAP, both methyltransferases, in adipogenesis remain unclear. This study investigated their effects on bovine preadipocyte differentiation using siRNA-mediated knockdown combined with transcriptomic analysis. Silencing METTL14 and WTAP significantly impaired lipid droplet formation and revealed distinct regulatory pathways: METTL14 knockdown affected genes like JAK2 and STAT3, while WTAP suppression down-regulated PPARγ/FABP4 signalling pathway components. These findings demonstrate that WTAP specifically modulates bovine adipocyte differentiation through the PPARγ/FABP4 pathway.

RNA-binding proteins as therapeutic targets in cancer

RNA-binding proteins (RBPs) have emerged as critical regulators of cancer progression, influencing virtually all hallmarks of cancer. Their ability to modulate gene expression patterns that promote or inhibit tumorigenesis has positioned RBPs as promising targets for novel anti-cancer therapies. This mini-review summarizes the current state of RBP-targeted cancer treatments, focusing on five examples, eIF4F, FTO, SF3B1, RBM39 and nucleolin. We highlight the diversity of current targeting approaches and discuss ongoing challenges including the complexity of RBP regulatory networks, potential off-target effects and the need for more specific targeting methods. By assessing the future potential of novel therapeutic avenues, we provide insights into the evolving landscape of cancer treatment and the critical role RBPs may play in next-generation therapeutics.

NVP-2, in combination with Orlistat, represents a promising therapeutic strategy for acute myeloid leukemia

Cell cycle dysregulation and the corresponding metabolic reprogramming play significant roles in tumor development and progression. CDK9, a kinase that regulates gene transcription and cell cycle, also induces oncogene transcription and abnormal cell cycle in AML cells. The function of CDK9 for gene regulation in AML cells requires further exploration. In this study, we knocked down the CDK9 to investigate its effects on the growth and survival of AML cells. Through RNA-seq analysis, we identified that in U937 cells CDK9 regulates numerous genes involved in proliferation and apoptosis, including mTOR, SREBF1, and Bcl-2. Furthermore, our results demonstrated that both CDK9 and FASN are crucial for the proliferation and survival of Kasumi-1 and U937 cells. Mechanistically, MCL1, c-Myc, and Akt/mTOR/SREBF1 may be critical factors and pathways in the combined therapy of NVP-2 and Orlistat. In summary, our study revealed that CDK9 and FASN are vital for maintaining AML cell survival and proliferation. Treatment with NVP-2 and Orlistat may be a promising clinical candidate for patients with AML.

The methyl-CpG binding domain 2 regulates peptidylarginine deiminase 4 expression and promotes neutrophil extracellular trap formation via the Janus kinase 2 signaling pathway in experimental severe asthma

OBJECTIVE

The prognosis for severe asthma is poor, and the current treatment options are limited. The methyl-CpG binding domain protein 2 (MBD2) participates in neutrophil-mediated severe asthma through epigenetic regulation. Neutrophil extracellular traps (NETs) play a critical role in the pathogenesis of severe asthma. This study aims to detect if MBD2 can reduce NETs formation and the potential mechanism in severe asthma.

METHODS

A severe asthma model was established in C57BL/6 wild-type mice exposure to house dust mite (HDM), ovalbumin (OVA), and lipopolysaccharide (LPS). Enzyme-linked immunosorbent assay was used to measure the concentrations of IL-4, IL-17A, and IFN-γ in lung tissues. Flow cytometry was employed to determine the percentages of Th2, Th17, and Treg cells in lung tissues. Quantitative real-time polymerase chain reaction was utilized to assess the mRNA expression levels of MBD2, JAK2, and PAD4. Western blotting and immunofluorescence were conducted to detect the protein of MBD2, JAK2, PAD4, and CitH3. HL-60 cells were differentiated into neutrophil-like cells by culturing in a medium containing dimethyl sulfoxide and then stimulated with LPS. KCC-07, Ruxolitinib, and Cl-amidine were used to inhibit the expressions of MBD2, JAK2, and PAD4, respectively.

RESULTS

Severe asthma mice were characterized by pulmonary neutrophilic inflammation and increased formation of neutrophil extracellular traps (NETs). The expression of MBD2, JAK2, and PAD4 was elevated in severe asthma mice. Inhibiting the expression of MBD2, JAK2, and PAD4 reduced NETs formation and decreased airway inflammation scores, total cell counts and neutrophil counts in BALF, and percentage of Th2 and Th17 cell in lung tissues, whereas increasing Treg cell counts. In both severe asthma mice and HL-60-differentiated neutrophil-like cells in vitro, inhibiting MBD2 reduced the mRNA and protein expression of JAK2 and PAD4, and inhibiting JAK2 reduced the expression of PAD4 mRNA and protein.

CONCLUSION

MBD2 regulates PAD4 expression through the JAK2 signaling pathway to promote NETs formation in mice with severe asthma. Further bench-based and bedside-based studies targeting the MBD2, PAD4, and JAK2 signaling pathways will help open new avenues for drug development of severe asthma.

Alternative splicing of the Snap23 microexon is regulated by MBNL, QKI, and RBFOX2 in a tissue-specific manner and is altered in striated muscle diseases

The reprogramming of alternative splicing networks during development is a hallmark of tissue maturation and identity. Alternative splicing of microexons (small, genomic regions ≤ 51 nucleotides) functionally regulate protein-protein interactions in the brain and is altered in several neuronal diseases. However, little is known about the regulation and function of alternatively spliced microexons in striated muscle. Here, we investigated alternative splicing of a microexon in the synaptosome-associated protein 23 (Snap23) encoded gene. We found that inclusion of this microexon is developmentally regulated and tissue-specific, as it occurs exclusively in adult heart and skeletal muscle. The alternative region is highly conserved in mammalian species and encodes an in-frame sequence of 11 amino acids. Furthermore, we showed that alternative splicing of this microexon is mis-regulated in mouse models of heart and skeletal muscle diseases. We identified the RNA-binding proteins (RBPs) quaking (QKI) and RNA binding fox-1 homolog 2 (RBFOX2) as the primary splicing regulators of the Snap23 microexon. We found that QKI and RBFOX2 bind downstream of the Snap23 microexon to promote its inclusion, and this regulation can be escaped when the weak splice donor is mutated to the consensus 5' splice site. Finally, we uncovered the interplay between QKI and muscleblind-like splicing regulator (MBNL) as an additional, but minor layer of Snap23 microexon splicing control. Our results are one of the few reports detailing microexon alternative splicing regulation during mammalian striated muscle development.

Distinctive function of Tetraspanins: Implication in viral infections

Harboring four transmembrane domains in their structural hallmark, Tetraspanins (Tspans) are a family of glycoproteins with pivotal functions in a variety of biological and cellular processes. Through interacting laterally with each other or specific membrane proteins, Tspans organize tetraspanin-enriched microdomains (TEMs), modulating cellular signaling, adhesion, fusion, and proliferation. An abundance of evidence has identified the multiple functions in the progression of cancer as well as the underlying molecular mechanisms. Recently, plenty of studies have focused on the utilities of Tspans by pathogens for infection, especially the infection of viruses. The expression of Tspans correlates with the phase of viral infection, the type of virus, and targeted therapies. In particular, perturbations of Tspans in host cells can affect viral attachment, intracellular trafficking, translation, virus assembly, and release. In this review, we summarize and provide a historical overview of the discovery and characterization of various kinds of virus infection and highlight their diversity and complexity, along with the virus life cycle. Furthermore, we examined the current understanding of how various Tspans are involved in the regulatory mechanisms underlying viral infection. This review aims to offer a comprehensive understanding of the targeting of Tspans for therapeutic intervention in infections caused by diverse pathogens.

Sorafenib-associated translation reprogramming in hepatocellular carcinoma cells

Sorafenib (Sfb) is a multikinase inhibitor regularly used for the management of patients with advanced hepatocellular carcinoma (HCC) that has been shown to increase very modestly life expectancy. We have shown that Sfb inhibits protein synthesis at the level of initiation in cancer cells. However, the global snapshot of mRNA translation following Sorafenib-treatment has not been explored so far. In this study, we performed a genome-wide polysome profiling analysis in Sfb-treated HCC cells and demonstrated that, despite global translation repression, a set of different genes remain efficiently translated or are even translationally induced. We reveal that, in response to Sfb inhibition, translation is tuned, which strongly correlates with the presence of established mRNA cis-acting elements and the corresponding protein factors that recognize them, including DAP5 and ARE-binding proteins. At the level of biological processes, Sfb leads to the translational down-regulation of key cellular activities, such as those related to the mitochondrial metabolism and the collagen synthesis, and the translational up-regulation of pathways associated with the adaptation and survival of cells in response to the Sfb-induced stress. Our findings indicate that Sfb induces an adaptive reprogramming of translation and provides valuable information that can facilitate the analysis of other drugs for the development of novel combined treatment strategies based on Sfb therapy.

Hesperidin alleviates pulmonary fibrosis by regulating EI24-mediated autophagy

BACKGROUND

Etoposide-induced protein 2.4 (EI24), an essential component of autophagy, is lowly expressed in pulmonary fibrosis. Hesperidin (Hes), a flavonoid, can regulate autophagy in various diseases. However, whether Hes can inhibit pulmonary fibrosis by mechanically regulating EI24-mediated autophagy has not been uncovered.

METHODS

RLE-6TN cells were treated with transforming growth factor β1 (TGF-β1) and rats were injected with bleomycin (BLM) to construct the pulmonary fibrosis model. The effect of Hes on pulmonary fibrosis was evaluated by cell counting kit-8, immunofluorescence, hematoxylin and eosin, masson trichome staining and western blotting.

RESULTS

Hes reduced cell viability of TGF-β1-induced RLE-6TN cells. Administration of Hes restored the decrease in autophagy marker levels in TGF-β1-induced RLE-6TN cells. Hes inhibited the transcriptional and translational levels of α-SMA, collagen I and fibronectin that were increased by TGF-β1 in RLE-6TN cells. Mechanically, Hes restored EI24 expression, and EI24 knockdown reversed the effect of Hes on the expressions of autophagy and fibrosis-related proteins. Additionally, Hes enhanced autophagy and fibrosis markers, which were worsened by EI24 knockdown in BLM-induced rats.

CONCLUSION

Hes activated autophagy by upregulating EI24, which improved pulmonary fibrosis both in vitro and in vivo.

Medicinal chemistry breakthroughs on ATM, ATR, and DNA-PK inhibitors as prospective cancer therapeutics

This review discusses the critical roles of Ataxia Telangiectasia Mutated Kinase (ATM), ATM and Rad3-related Kinase (ATR), and DNA-dependent protein kinase (DNA-PK) in the DNA damage response (DDR) and their implications in cancer. Emphasis is placed on the intricate interplay between these kinases, highlighting their collaborative and distinct roles in maintaining genomic integrity and promoting tumour development under dysregulated conditions. Furthermore, the review covers ongoing clinical trials, patent literature, and medicinal chemistry campaigns on ATM/ATR/DNA-PK inhibitors as antitumor agents. Notably, the medicinal chemistry campaigns employed robust drug design strategies and aimed at assembling new structural templates with amplified DDR kinase inhibitory ability, as well as outwitting the pharmacokinetic liabilities of the existing DDR kinase inhibitors. Given the success attained through such endeavours, the clinical pipeline of DNA repair kinase inhibitors is anticipated to be supplemented by a reasonable number of tractable entries (DDR kinase inhibitors) soon.

Research progress on the mechanism of tumor cell ferroptosis regulation by epigenetics

Cancer remains a significant barrier to human longevity and a leading cause of mortality worldwide. Despite advancements in cancer therapies, challenges such as cellular toxicity and drug resistance to chemotherapy persist. Regulated cell death (RCD), once regarded as a passive process, is now recognized as a programmed mechanism with distinct biochemical and morphological characteristics, thereby presenting new therapeutic opportunities. Ferroptosis, a novel form of RCD characterized by iron-dependent lipid peroxidation and unique mitochondrial damage, differs from apoptosis, autophagy, and necroptosis. It is driven by reactive oxygen species (ROS)-induced lipid peroxidation and is implicated in tumorigenesis, anti-tumor immunity, and resistance, particularly in tumors undergoing epithelial-mesenchymal transition. Moreover, ferroptosis is associated with ischemic organ damage, degenerative diseases, and aging, regulated by various cellular metabolic processes, including redox balance, iron metabolism, and amino acid, lipid, and glucose metabolism. This review focuses on the role of epigenetic factors in tumor ferroptosis, exploring their mechanisms and potential applications in cancer therapy. It synthesizes current knowledge to provide a comprehensive understanding of epigenetic regulation in tumor cell ferroptosis, offering insights for future research and clinical applications.

Zellweger syndrome; identification of mutations in PEX19 and PEX26 gene in Saudi families

BACKGROUND

Peroxisome biogenesis disorders (PBD) affect multiple organ systems. It is characterized by neurological dysfunction, hypotonia, ocular anomalies, craniofacial abnormalities, and absence of peroxisomes in fibroblasts. PBDs are associated with mutations in any of fourteen different PEX genes, which are involved in peroxisome biogenesis. Zellweger spectrum disorder (ZSD) is a severe form of PBD. More than 90% of the ZSD cases have mutations in PEX1, PEX6, PEX10, PEX12, and PEX26. Mutations in the PEX19 gene are rarely associated with PBD/ZSD; however, a large proportion of PEX26 mutations are associated with ZSD.

METHODS

We recruited two Saudi families with multiple affected individuals with dysmorphic features, including hypertelorism, large open fontanelles, generalized hypotonia, and epicanthal folds with poor reflexes since birth. Whole exome sequencing (WES) and Sanger sequencing was performed to identify the genetic cause. The frequency and pathogenicity of the identified mutations were assessed using various online bioinformatics tools.

RESULTS

WES identified a novel nonsense variant (c.367C > T) in the PEX19 gene in family A patients. This nonsense mutation was predicted to cause premature termination (p.Gln123*). A previously reported synonymous variant (c.228C > T; p.Gly76Gly) in PEX26 was found in a patient from family B. Both variants were segregating in an autosomal recessive manner in the respective families.

CONCLUSION

The present study has added a novel nonsense mutation to the mutation spectrum of PEX19, which is the second null mutation identified to date. Moreover, in this study, the importance of a synonymous exonic variant of PEX26 close to the splice donor site was explored in relation to pre-mRNA splicing and resulting disease manifestations.

CircMYH9 promotes the mRNA stability of SPAG6 by recruiting EIF4A3 to facilitate the progression of breast cancer

The incidence rate of breast cancer (BC) ranks first among female malignant tumors. Late-stage BC patients are at risk of death from distant metastasis. Circular RNAs (circRNAs) play an important function in cancer development. This study looked at the role of circMYH9 in BC. The nude mouse tumor-bearing experiment was used to verify the role of circMYH9 in regulating BC tumor growth in mice. Gene expression and protein amount were tested by qRT-PCR, western blot, and IHC. The pathological changes in tumor tissues were analyzed by HE staining. Cell viability, proliferation, migration, and invasion were assessed using CCK8, colony formation assay, wound healing assay, and Transwell assay, respectively. The interactions between circMYH9, SPAG6, and EIF4A3 were analyzed by RIP assay. CircMYH9 was significantly upregulated in BC, and its upregulated was related to poor prognosis. CircMYH9 silencing markedly impaired BC cell proliferation, migration, and invasion. Mechanistically, circMYH9 promoted the mRNA stability and expression of SPAG6 by recruiting EIF4A3. As expected, SPAG6 overexpression abrogated inhibition mediated by circMYH9 knockdown on BC cell malignant behaviors. In addition, circMYH9 knockdown inhibited PI3K/Akt signal pathway by increasing PTEN expression in BC cells, while was reversed by SPAG6 upregulation. PTEN inhibition abolished inhibition induced by circMYH9 downregulation on BC malignant progression. Moreover, circMYH9 silencing inhibited tumor growth in mice. CircMYH9 overexpression regulated the PTEN/PI3K/AKT pathway by increasing SPAG6 mRNA stability through recruiting EIF4A3, thereby promoting BC malignant progression.

Reduced DNMT1 expression associated with TP53 promoter hypomethylation mediate enhanced granulosa cell senescence during ovarian aging

BACKGROUND

The effects of granulose cell (GC) senescence on premature ovarian insufficiency/premature ovarian failure have been extensively examined, the association between GC senescence and ovarian aging remains to be clarified.

METHODS

Human and mouse GCs from young/control and old/advanced maternal age (AMA) groups were collected, and GC senescence was determined. The role of the DNMT1-p53 axis in GC senescence during ovarian aging was examined and validated in a KGN cell senescence model.

RESULTS

SA-beta-gal-positive GCs were significantly increased in the AMA group, accompanied by activation of the p53-p21 pathway, which was also found in GCs from aged mice and H2O2-induced senescent KGN cells. Pyrosequencing methylation analysis revealed that increased expression of p53 was associated with decreased average methylation levels of CpG sites (-1031, -1019, -1012 and -1008) within the P53 promoter CpG island in senescenct GCs and KGN cells. We further found that decreased DNA-methyltransferase 1 (DNMT1) expression was responsible for the reduced methylation levels of the CpG sites.

CONCLUSION

Decreased DNMT1 with hypomethylation of the CpG sites within the P53 promoter CpG island in GCs is involved in ovarian aging.

Modifying non-coding regions of linear DNA vaccines to explore the interplay of expression and inflammation in immunogenicity

The COVID-19 pandemic highlighted the need for rapidly deployable, flexible vaccine platforms; particularly RNA which is now being explored for several other pathogens. DNA vaccines have potential advantages over RNA, including cost of manufacture, ease of storage and potentially lower reactogenicity. However, they have historically underperformed in large animals and human trials due to low immunogenicity. The interplay between antigen expression and the innate immune response impacts the overall immune response to DNA vaccines. Here, we explore the effect of altering non-coding 5' regions, on the immunogenicity of a closed linear DNA platform, Doggybone™ DNA (dbDNATM), produced by a rapid and scalable cell-free method. Using a mouse model, we found that enhancer sequences and DNA targeting sequences (DTS) increased influenza virus hemagglutinin (HA) expression and improved immune responses. Additional CpG motifs did not provide any immune benefit. We also found that the effect of non-coding sequences was target specific, with differing effects in influenza HA, SARS-CoV-2 Spike and eGFP constructs. To separate the effects of immune sensing of the DNA construct and the expression of the encoded antigen, we combined a separate CpG oligodeoxynucleotide (ODN) with the highest expressing DNA vaccine; we observed reduced expression, but higher inflammation resulting in equivalent immunogenicity. Further refinement is required to fully understand the interplay of factors required for the induction of protective immunity by DNA vaccines.