P53 Signaling Research Articles

Effects of BET Inhibition on lung micro-environmental changes in obesity-related pulmonary Arterial Hypertension (PAH)

Abstract Background Obesity is emerging as a pivotal risk factor for pulmonary arterial hypertension (PAH) but the underlying molecular mechanisms are poorly explored. The lung microenvironment, namely the cell-cell communication among fibroblasts, immune and endothelial cells, may significantly impact on vascular structure and function thus promoting microvascular disease in this setting. Obesity-induced chromatin modifications lead to maladaptive transcriptional programs altering cell function in different organs. Apabetalone (APA), a selective inhibitor of bromodomain and extra-terminal containing protein family (BET) proteins, prevents bromodomain-containing protein 4 (BRD4) interactions with chromatin thus modulating gene expression. Purpose To determine whether a new epi-drug, namely APA, affects the lung microenvironment in obesity-related PAH. Methods Mice were fed a normal diet (ND, control) or high-fat-diet (HFD) and L-NAME for 15 weeks to induce obesity-related PAH (obPAH). Echocardiography was performed. Pathways regulating obPAH were identified by single-cell nuclei RNA sequencing in lung specimens. Primary endothelial cells (ECs) and Fibroblasts (mFs) were freshly isolated from obPAH lungs and treated with APA for 48 hours. Cells and lung samples were used for molecular biology and histology. Cellular migration was investigated by in vitro gap closure. Results Obese mice displayed PAH as shown by increased pulmonary artery (PA) pressure, PA resistance, right ventricular wall thickness and reduced PA acceleration time. Of note, chronic APA treatment prevented PAH-related features in obese mice. To determine the cell types affected by APA, we performed scRNAseq. We found that fibroblast and endothelial cells had the highest enrichment of genes whose expression significantly correlated with echo-determined PAH features. ECs and mFs from obese mice displayed an altered phenotype whereas treatment with APA rescued obesity-driven ECs and mFs dysfunction. In obPAH ECs, we found increased expression of NF-kB p65-related inflammatory genes (IL-1β, IL-6, TNF-alpha) as well as enhanced p53 signaling. Moreover, obPAH-ECs expressed high levels of hypoxia-inducible factor (HIF1-α) and NADPH-oxidase-NOX4 with subsequent increase in ROS generation. Furthermore, APA treatment protected against cellular inflammation, senescence and oxidative stress. To evaluate the effect of APA and the paracrine response of fibroblasts, we performed a scratch assay on control mFs exposed to TGF-β or conditioned media collected from obPAH-ECs with and without APA. In both experimental settings, APA affected gap closure, suggesting that the treatment influences fibroblast migration through both a direct effect and paracrine mechanisms. Conclusions APA is able to reset the lung micro-envirnment in obesity thus reducing inflammation and senescence. BET inhibitors could represent potential therapeutic approaches in this setting.

Vaccination targeting senescence-associated transmembrane protein alleviated cardiovascular pathology in the mice

Abstract Introduction Accumulation of senescent cells is observed in various organs including vasculature, heart and white adipose tissue with age, and known to become a substrate of pathophysiology of various cardiovascular-metabolic diseases. We have previously developed a vaccine to eliminate senescent cells, so-called "senolytic vaccine" by targeting Glycoprotein Nonmetastatic Melanoma Protein B (GPNMB) as a cellular-senescence-associated cell surface protein. We have demonstrated that GPNMB senolytic vaccine could remove senescent cells and alleviate the pathology cardiovascular-metabolic diseases. Senescence-associated adhesion molecule 1 (SAAM-1) is also known as a cell-surface membrane to increase its expression during cellular senescence in endothelial cells as well as the development of cardiovascular diseases. Here, we identified SAAM-1 as another senescence antigen and created a vaccine to eliminate senescent cells by targeting SAAM-1. Purpose This study was purposed to evaluate the efficacy of SAAM-1 vaccine for the treatment of cardiovascular diseases in mice models. Methods As a pressure overload-induced heart failure (HF) model, C57BL/6N wild type (WT) mice were underwent transverse aortic constriction (TAC) or sham opretaion at 13 weeks of age. SAAM-1 or control vaccination were given at 8 and 10 weeks of age before operation. Echocardiography examination was conducted two weeks after TAC operation, followed by tissue sampling 3 weeks after the examination. As an atherosclerosis model, ApoE KO mice were subjected to a high-fat diet (HFD) starting at 4 weeks of age. Vaccination of ApoE KO mice was administered at 8 weeks of age with SAAM-1-vaccine or control-vaccine, followed by sacrifice 4 weeks later for further analysis. ApoE-KO mice were also crossed with p16-mediated Luciferase expressing mice (p16-Luc mice) and subjected to generation of atherosclerosis model. Results SAAM-1 expression was significantly increased in left ventricle (LV) in TAC mice but its increase was suppressed by SAAM-1 vaccination. Interestingly, both worsening systolic function and dilatation of LV by pressure overload were significantly alleviated by SAAM-1 vaccination. Furthermore, expression level of senescent markers including p16 and p21, as well as several inflammation markers were increased in failing heart along with development of cardiac fibrosis, but SAAM-1 vaccine could significantly attenuate this pathological change. In ApoE KO mice, SAAM-1 vaccine decreased expression level of several inflammation markers in the mice, along with a decreasing p16 signal in the aorta. Conclusions Targeting SAAM-1 for vaccination would be a novel and promising approach to alleviating age-related cardiovascular disease.

P53 terminates the regenerative fetal-like state after colitis-associated injury.

Cells that lack p53 signaling frequently occur in ulcerative colitis (UC) and are considered early drivers in UC-associated colorectal cancer (CRC). Epithelial injury during colitis is associated with transient stem cell reprogramming from the adult, homeostatic to a "fetal-like" regenerative state. Here, we use murine and organoid-based models to study the role of Trp53 during epithelial reprogramming. We find that p53 signaling is silent and dispensable during homeostasis but strongly up-regulated in the epithelium upon DSS-induced colitis. While in WT cells this causes termination of the regenerative state, crypts that lack Trp53 remain locked in the highly proliferative, regenerative state long-term. The regenerative state in WT cells requires high Wnt signaling to maintain elevated levels of glycolysis. Instead, Trp53 deficiency enables Wnt-independent glycolysis due to overexpression of rate-limiting enzyme PKM2. Our study reveals the context-dependent relevance of p53 signaling specifically in the injury-induced regenerative state, explaining the high abundance of clones lacking p53 signaling in UC and UC-associated CRC.

Polyethylene Terephthalate Microplastic Exposure Induced Reproductive Toxicity Through Oxidative Stress and p38 Signaling Pathway Activation in Male Mice

Polyethylene terephthalate (PET) is a type of polymer plastic that is often used to make plastic bags, bottles, and clothes. However, the waste of such plastic products is decomposed into microplastics (MPs), which are plastic fragments smaller than 5 mm, by various external forces such as wind, UV radiation, mechanical wear, and biodegradation. PET MPs have been widely detected in the environment and human tissue samples; however, the toxicity and mechanism of PET MPs in mammals are still unclear. In this study, we investigated the male reproductive toxicity of PET MPs and their underlying mechanism. A total of 80 male mice were orally exposed to 0.01, 0.1, and 1 mg/d of PET MPs (with a diameter of 1 μm) for 42 days. The results showed that 1 μm PET MPs induced different degrees of pathological damage to testicular tissues, decreased sperm quality, and increased the apoptosis of spermatogenic cells via oxidative stress and p38 signaling pathway activation. To further illustrate and verify the mechanistic pathway, oxidative stress was antagonized using N-acetylcysteine (NAC), and the activation of the p38 signaling pathway was blocked using SB203580. The results revealed that the male reproductive injury effects after exposure to PET MPs were significantly ameliorated. Specifically, the testicular tissue lesions were relieved, the sperm quality improved, and the apoptosis of spermatogenic cells decreased. These results demonstrated that PET MP exposure induced male reproductive toxicity through oxidative stress and the p38 signaling pathway. This study provides new insights into the reproductive toxicity of MPs in males, as well as valuable references for public health protection strategies.

Unveiling novel prognostic biomarkers and therapeutic targets for HBV-associated hepatocellular carcinoma through integrated bioinformatic analysis.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths globally, with limited treatment options. The goal of this study was to use integrated bioinformatic analysis to find possible biomarkers for prognosis and therapeutic targets for hepatitis B (HBV)-associated HCC. Three microarray datasets (GSE84402, GSE121248, and E-GEOD-19665) from patients with HBV-associated HCC were combined and analyzed. We identified differentially expressed genes (DEGs) and performed pathway enrichment analysis. We constructed protein-protein interaction networks to identify hub genes. We identified a total of 374 DEGs, which included 90 up-regulated and 284 down-regulated genes. Pathway enrichment analysis revealed associations with cell cycle, oocyte meiosis, and the p53 signaling pathway for up-regulated DEGs. Twenty hub genes were identified, and 9 of them (ZWINT, MELK, DLGAP5, BIRC5, AURKA, HMMR, CDK1, TTK, and MAD2L1) were validated using the Cancer Genome Atlas data and Kaplan-Meier survival analysis. These genes were significantly associated with a poor prognosis in HCC patients. Our research shows that ZWINT, MELK, DLGAP5, BIRC5, AURKA, HMMR, CDK1, TTK, and MAD2L1 may be useful for predicting how HBV-associated HCC will progress and for finding new ways to treat it. In addition to these further studies are needed to elucidate the functions of the remaining 11 identified hub genes (RRM2, NUSAP1, PBK, CCNB1, CCNB2, BUB1B, NEK2, CENPF, ASPM, TOP2A, and BUB1) in HCC development and progression.

SKI-606, a Src inhibitor, ameliorates benzene-induced hematotoxicity via blocking ROS/Src kinase-mediated p38 and Akt signaling pathways

Exposure to benzene causes acute myelosuppression and other hematologic disorders. However, the detailed mechanism by which benzene exerts its severe hematotoxicity and potential treatments still require further deciphering and exploration. Herein, we found that hydroquinone (HQ), a main benzene metabolite, significantly increased intracellular reactive oxygen species (ROS) formation and subsequently caused damage to DNA, leading to impaired colony formation capacity and induction of apoptosis in human hematopoietic stem/progenitor cells (HSPCs) in vitro. The effects were mediated by activation of Src kinase, which subsequently activated the p38 signaling pathway while inhibiting the Akt signaling pathway. The mechanism was further verified by pre-treatment with a Src kinase inhibitor SKI-606, which effectively reversed the dampened self-renewal capacity and increased apoptosis of HSPCs induced by HQ in vitro. Furthermore, administration of SKI-606 partially reversed benzene-induced hematotoxicity and prolonged the survival time in benzene-poisoned mice. Taken together, these findings highlight that HQ-induced hematotoxicity in HSPCs is attributed to the Src kinase-mediated activation of p38 signaling pathway and repression of Akt signaling pathway. Notably, SKI-606 as a tyrosine kinase inhibitor may be a promising and potential agent for alleviating benzene-induced hematotoxicity.

Hippo signaling cooperates with p53 to regulate lung airway mucous cell metaplasia.

Airway mucous cell metaplasia is a significant feature of many chronic airway diseases, such as chronic obstructive pulmonary disease (COPD), cystic fibrosis, and asthma. However, the mechanisms underlying this process remain poorly understood. Here, we employ in vivo mouse genetic models to demonstrate that Hippo and p53 cooperate to modulate the differentiation of club cells into goblet cells. We reveal that ablation of Mst1 and Mst1 (Mst1/2), the core components of Hippo signaling, significantly reduces mucous metaplasia in the lung airways in a lipopolysaccharide (LPS)-induced lung inflammation murine model while promoting club cell proliferation in a Yap-dependent manner. Additionally, we show that deleting Mst1/2 is sufficient to suppress p53 deficiency-mediated goblet cell metaplasia. Finally, single-cell RNA analysis reveals a downregulation of Yap and p53 signaling in goblet cells in the human airways. These findings underscore the important role of Hippo and p53 signaling in regulating airway mucous metaplasia.

Evaluation of Echinacea purpurea Extracts as Immunostimulants: Impact on Macrophage Activation.

Echinacea purpurea has been traditionally used to strengthen the immune system. Therefore, herein, we investigated the potential of E. purpurea aqueous extracts (AEs) obtained from flowers (F), leaves (L), or roots (R) as an immune booster in human primary monocyte-derived macrophages (hMDMs). Additionally, to identify the main class of compounds (phenolic/carboxylic acids vs. alkylamides) responsible for the bioactivity, the three AEs were fractioned by semi-preparative high-performance liquid chromatography (HPLC). The AEs and the isolated phenolic/carboxylic acidic fractions were not cytotoxic for hMDMs for all tested concentrations, as confirmed by the metabolic activity and DNA content assays. Moreover, AE drastically induced the production of the interleukin (IL)-6 and tumor necrosis factor (TNF)-α, with a minimal effect on IL-1β and prostaglandin E2 (PGE2), supporting their potential for macrophage activation. Interestingly, in the presence of the phenolic/carboxylic acidic fractions, this efficacy considerably decreased, suggesting a complementary effect between compounds. AE also triggered the phosphorylation of the extracellular signal-regulated kinase (ERK) 1/2 and p38 signaling pathways and upregulated the cyclooxygenase (COX)-2 expression in hMDMs. Overall, AE-F was demonstrated to be the most powerful immunostimulant extract that can be related to their higher number in identified bioactive compounds compared to AE-L and AE-R. These results highlight the efficiency of E. purpurea AE to enhance the function of a key cell type of the immune system and their potential as immunostimulant formulations for patients with a compromised immune system due to certain diseases (e.g., acquired immunodeficiencies) and treatments (e.g., chemotherapy).

H3K27 Acetylation-Activated GLDC Accelerated the Advancement of Oral Squamous Cell Carcinoma by Suppressing the p53 Signaling Pathway.

Glycine decarboxylase (GLDC) has been identified to be dysregulated and plays pivotal roles in various cancers. Besides, studies have suggested that GLDC expression is elevated in oral squamous cell carcinoma (OSCC) and associated with a worse prognosis, but the precise role and molecular mechanism of GLDC in OSCC remain unexplored. The current study first confirmed the high expression of GLDC in OSCC and its correlation with worse survival in patients with OSCC. By knocking down GLDC, it was discovered that the growth and colony formation of OSCC cells, as well as the development of xenograft tumors, were effectively suppressed. In addition, GLDC deficiency inhibited the migration and invasion of OSCC cells in vitro through regulating EMT markers and attenuated lung metastasis in vivo. Mechanistically, GLDC was found to affect the activity of the p53 signaling pathway. GLDC depletion retarded the progression of OSCC by activating the p53 signaling pathway. Moreover, p300 co-functioned with TFAP2A to induce acetylation of GLDC, which resulted in the upregulation of GLDC in OSCC. To conclude, acetylation-induced GLDC upregulation facilitated the tumorigenesis and metastasis of OSCC by its inhibition of the activity of the p53 signaling pathway.

Chronic kidney disease amplifies severe kidney injury and mortality in a mouse model of skin arsenical exposure.

In previously published work, we elucidated the role of cutaneous arsenical exposure in promoting acute kidney injury (AKI) in adult healthy mice. Here, we determine whether pre-existing chronic kidney disease (CKD) increases the severity of AKI. Following exposure to aristolochic acid (AA) (a nephrotoxic phytochemical in humans), mice manifested classical markers of CKD, including robust interstitial fibrosis and loss in kidney function. Skin challenge with phenylarsine oxide (PAO), a surrogate for warfare arsenicals, led to significantly worse kidney injury, as evidenced by tubulointerstitial fibrosis, glomerulosclerosis, a persistent loss of estimated glomerular filtration rate and mortality in AA-induced CKD mice compared to mice without CKD. These PAO-challenged CKD mice exhibited enhanced production of serum/urine NGAL, and a significant rise in serum creatinine along with histological markers of kidney injury, including brush border loss, tubular atrophy, cast formation, glomerular injury, and interstitial inflammatory cell infiltration. Serum cytokines IL-4, IL-6, IFN-γ, IL-12p70, TNF-α, and IL-18 significantly elevated in CKD mice following PAO exposure when compared to animals exposed to PAO alone. Furthermore, we found increased TUNEL-positive tubular cells in the kidneys of CKD mice following PAO exposure, suggesting enhanced PAO-mediated cell death in CKD mice. Mechanistically, we determined that DNA damage-regulated p53 signaling was a major mediator of cellular responses to PAO in CKD mice. In summary, our data demonstrate that CKD significantly increased severity of AKI following exposure to arsenicals and suggest that human populations with preexisting CKD could be highly susceptible to arsenical-mediated kidney injury and associated morbidity and mortality.

Jianpi qingre tongluo prescription alleviates the senescence-associated secretory phenotype with osteoarthritis by regulating STAG1/TP53/P21 signaling pathway

Ethnopharmacological relevanceJianpi Qingre Chubi prescription primarily consists of a compound formula, also known as Huangqin Qingre Chubi Capsules (HQC), which strengthens the spleen and resolves dampness, clear heat, and collaterals. Long-term clinical use has shown that HQC improves joint swelling and pain in patients with osteoarthritis. Mechanistically, we demonstrated that HQC inhibits inflammatory responses, extracellular matrix degradation, and delays chondrocyte senescence. AimTo determine the bioactivity and mechanism of action of Jianpi Qingre Tongluo prescription (HQC) on osteoarthritis (OA). Materials and methodsFirst, the chondroprotective effects of HQC were assessed using histopathology, immunohistochemical staining and protein blotting in an OA rat model. Additionally, we identified key targets for crucial targets of HQC in OA using the Network Pharmacology and Gene Expression Omnibus (GEO) dataset (GSE98918 and GSE152805). In vitro conditions, IL-1β-treated chondrocytes served to study the impact of HQC on OA development and the senescence-associated secretory phenotype (SASP). This was evaluated using a series of approaches, such as flow cytometry assays, and immunofluorescence staining, and then verified by rescue experiments. ResultsTherapy with HQC attenuated the severity of osteoarthritis (demonstrated by histopathology, OARSI grading scores, and Mankin scores) and SASP factors (as indicated by IL-1β, IL-6, IL-4, IL-37, MMP13, ADAMTS5, COL2A1, and ACAN levels, and apoptotic cell death). HQC might treat osteoarthritis via four important targets (STAG1, TP53, P21, and P16), with the p53 signalling pathway representing one of the main pathways. The HQC acts primarily on chondrocyte clusters. In vitro experiments indicated that STAG1 overexpression accelerates chondrocyte apoptosis, promotes SASP factor expression and extracellular matrix (ECM) degradation, and facilitates OA progression. HQC-containing serum suppressed the expression of the STAG1/TP53/P21 pathway, regulated SASP factors, and restored ECM balance. ConclusionJianpi Qingre Tongluo prescription modulated SASP factors by regulating the STAG1/TP53/P21 signal transduction axis and decelerating cartilage senescence and degradation in patients with OA. Jianpi Qingre Tongluo may be an effective drug candidate.

Citrus extraction provides neuroprotective effect in optic nerve crush injury mice through P53 signaling pathway

Optic nerve injury induces the loss of retinal ganglion cells and optic nerve atrophy. Our previous study demonstrated the neuroprotective effects of Citrus in the optic nerve crush (ONC) injury model. To explore the underlying neuroprotective mechanism, we focus on the changes in gene expression profile pre- and post-Citrus treatment in the ONC injury model. The results suggested that the Citrus regulated the chemokine signaling pathway and P53 signaling pathway, etc. Four genes were identified as potential target genes (Melk, Mki67, Ccnb1, and Cenpf). Subsequent qRT-PCR and western blot confirmed that Citrus regulated cell apoptosis and inflammation-related gene expression, and inhibited P53 activation-induced cell death. The present study demonstrated that the neuroprotective effect of Citrus was achieved through the regulation of the P53/BCL-2/BAX pathway and the expression regulation of four critical genes, which provide novel therapeutic targets for the therapy of optic nerve injury.

Procollagen C-protease enhancer protein promotes glioma growth by activating ERK signaling.

Procollagen C-proteinase enhancer (PCOLCE) promotes tumor progression in multiple cancers. However, the specific role of PCOLCE in gliomas remains enigmatic. In this study, we focused on analyzing PCOLCE expression and its correlation with clinicopathological parameters in glioma specimens; moreover, we explored the effects of PCOLCE in glioma proliferation in vitro and in vivo. A tissue microarray containing 159 human glioma specimens was pressed to explore the correlation between PCOLCE expression and the survival of glioma patients. Cell Counting Kit-8 (CCK8), colony formation, and immunoblot assays were used to detect the role of PCOLCE on cell proliferation in glioma. Furthermore, the in vivo role of PCOLCE was investigated using a subcutaneous glioma xenograft model. The expression of PCOLCE was higher in grade III and IV gliomas than in grade I and II gliomas. High PCOLCE expression was related to a remarkably worse prognosis in glioma patients. Additionally, PCOLCE downregulation impeded glioma cell proliferation. Furthermore, PCOLCE knockdown markedly abrogated p-ERK expression in glioma cells, whereas, it negligibly influenced p38 and JNK signaling. These results indicate that PCOLCE is a feasible prognostic biomarker for glioma, and PCOLCE-induced activation of ERK signaling may be a pro-growth mechanism in glioma cells.

Amphiregulin Upregulation in Visfatin-Stimulated Colorectal Cancer Cells Reduces Sensitivity to 5-Fluororacil Cytotoxicity.

Colorectal cancer (CRC) has become a prevalent and deadly malignancy over the years. Drug resistance remains a major challenge in CRC treatment, significantly affecting patient survival rates. Obesity is a key risk factor for CRC development, and accumulating evidence indicates that increased secretion of adipokines, including Visfatin, under obese conditions contributes to the development of resistance in CRC to various therapeutic methods. Amphiregulin (AREG) is a member of the epidermal growth factor (EGF) family, which activates the EGF receptor (EGFR), influencing multiple tumorigenic characteristics of cancers. Abnormal expression levels of AREG in cancer cells have been associated with resistance to anti-EGFR therapy in patients. However, it remains unclear whether this abnormal expression also impacts CRC resistance to other chemotherapeutic drugs. The aim of this study is to examine whether AREG expression levels could be affected in CRC cells under Visfatin stimulation, thereby initiating the development of resistance to 5-fluororacil (5-FU). Through our results, we found that Visfatin indeed increases AREG expression, reducing the sensitivity of HCT-116 CRC cells to 5-FU cytotoxicity. Moreover, AREG upregulation is regulated by STAT3-CREB transcription factors activated by JNK1/2 and p38 signaling. This study highlights the significant role of AREG upregulation in CRC cells in initiating chemotherapeutic resistance to 5-FU under Visfatin stimulation. These findings provide a deeper understanding of drug resistance development in CRC under obese conditions and offer new insights into the correlation between an abnormal increase in AREG levels and the development of 5-FU-resistance in CRC cells, which should be considered in future clinical applications.

Copper Nanoparticles Green-Formulated byCurcuma longa Extract Induce Apoptosis via P53 and STAT3 Signaling Pathways in Bladder Carcinoma Cell.

The study outlines the production of new copper nanoparticles infused with Curcuma longa extract to trigger apoptosis through P53 and signal transducer and activator of transcription 3 (STAT3) signaling pathways in bladder carcinoma cells. The structural characteristics of the nanoparticles that were synthesized were analyzed through various sophisticated methods such as transmission electron microscopy (TEM), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR). During the antioxidant evaluation, the IC50 values for copper nanoparticles and butylated hydroxytoluene (BHT) against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals were found to be 116µg/mL and 31µg/mL, respectively. The cells treated with copper nanoparticles underwent evaluation through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay for 48h to determine their anticancer properties on TCCSUP bladder carcinoma cell. The TCCSUP cell line exhibited an IC50 of 290µg/mL when exposed to copper nanoparticles. The viability of malignant cells decreased upon treatment with copper nanoparticles. Furthermore, the copper nanoparticles presence led to a 65-75% increase in cell apoptosis, along with an increase in Bax and cleaved caspase-8 and a decrease in the Bcl-2. Furthermore, the copper nanoparticles presence resulted in the suppression of colony formation. Notably, the molecular pathway analysis in cells treated with copper NPs demonstrated an increase in p53 expression, along with a decrease in the expression of both total and phosphorylated STAT3. This offers that p53 and STAT3 play a crucial role in the biological efficacies induced by the nanoparticles in human carcinoma cells. The data of our research suggest that copper NPs could have significant potential as an anticancer treatment for human bladder carcinoma cells.

The NOTCH1 and miR-34a signaling network is affected by TP53 alterations in CLL

In chronic lymphocytic leukemia (CLL), TP53 mutations or deletions on chromosome 17p lead to adverse prognosis and reduced levels of miR-34a, which targets NOTCH1. Also, hyperactivated NOTCH1 signaling is crucial for CLL progression. Here we explored the interaction between p53, miR-34a, and NOTCH1 in CLL. We investigated the effect of p53 and miR-34a on NOTCH1 signaling and expression in CLL cells with altered TP53. Our results indicate that miR-34a reduces NOTCH1 3’ UTR activity but might not be a mediator between p53 signaling and NOTCH1. p53 activation increases miR-34a expression and NOTCH1 protein levels, correlating with decreased NOTCH1 and miR-34a levels in primary CLL cells with TP53 alterations. Some samples with high NOTCH1 levels presented increased BCL-2, suggesting an anti-apoptotic mechanism of a potentially direct p53-NOTCH1 relation in CLL. This study deepens the understanding of the p53-miR-34a-NOTCH1 signaling network, providing insights that could guide future therapeutic strategies for CLL.

Loss of NAT10 Reduces the Translation of Kmt5a mRNA Through ac4C Modification in Cardiomyocytes and Induces Heart Failure.

In the past decade, the biological functions of various RNA modifications in mammals have been uncovered. N4-acetylcytidine (ac4C), a highly conserved RNA modification, has been implicated in human diseases. Despite this, the involvement of RNA ac4C modification in cardiac physiology and pathology remains incompletely understood. NAT10 (N-acetyltransferase 10) stands as the sole acetyltransferase known to catalyze RNA ac4C modification. This study aims to explore the role of NAT10 and ac4C modification in cardiac physiology and pathology. Cardiac-specific knockout of NAT10, leading to reduced RNA ac4C modification, during both neonatal and adult stages resulted in severe heart failure. NAT10 deficiency induced cardiomyocyte apoptosis, a crucial step in heart failure pathogenesis, supported by invitro data. Activation of the p53 signaling pathway was closely associated with enhanced apoptosis in NAT10-deficient cardiomyocytes. As ac4C modification on mRNA influences translational efficiency, we employed ribosome footprints coupled with RNA sequencing to explore genome-wide translational efficiency changes caused by NAT10 deficiency. We identified and validated that the translational efficiency of Kmt5a was suppressed in NAT10 knockout hearts due to reduced ac4C modification on its mRNA. This finding was consistent with the observation that Kmt5a protein levels were reduced in heart failure despite unchanged mRNA expression. Knockdown of Kmt5a in cardiomyocytes recapitulated the phenotype of NAT10 deficiency, including increased cardiomyocyte apoptosis and activated p53 signaling. Finally, overexpression of Kmt5a rescued cardiomyocyte apoptosis and p53 activation induced by NAT10 inhibition. Our study highlights the significance of NAT10 in cardiomyocyte physiology, demonstrating that NAT10 loss is sufficient to induce cardiomyocyte apoptosis and heart failure. NAT10 regulates the translational efficiency of Kmt5a, a key mediator, through mRNA ac4C modification during heart failure.

Transcriptome-wide N6-methyladenosine modification profiling of long non-coding RNAs in patients with recurrent implantation failure

N6-methyladenosine (m6A) is involved in most biological processes and actively participates in the regulation of reproduction. According to recent research, long non-coding RNAs (lncRNAs) and their m6A modifications are involved in reproductive diseases. In the present study, using m6A-modified RNA immunoprecipitation sequencing (m6A-seq), we established the m6A methylation transcription profiles in patients with recurrent implantation failure (RIF) for the first time. There were 1443 significantly upregulated m6A peaks and 425 significantly downregulated m6A peaks in RIF. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that genes associated with differentially methylated lncRNAs are involved in the p53 signalling pathway and amino acid metabolism. The competing endogenous RNA network revealed a regulatory relationship between lncRNAs, microRNAs and messenger RNAs. We verified the m6A methylation abundances of lncRNAs by using m6A-RNA immunoprecipitation (MeRIP)–real-time polymerase chain reaction. This study lays a foundation for further exploration of the potential role of m6A modification in the pathogenesis of RIF.

Lipid peroxidation products induce carbonyl stress, mitochondrial dysfunction, and cellular senescence in human and murine cells.

Lipid enals are electrophilic products of lipid peroxidation that induce genotoxic and proteotoxic stress by covalent modification of DNA and proteins, respectively. As lipid enals accumulate to substantial amounts in visceral adipose during obesity and aging, we hypothesized that biogenic lipid enals may represent an endogenously generated, and therefore physiologically relevant, senescence inducers. To that end, we identified that 4-hydroxynonenal (4-HNE), 4-hydroxyhexenal (4-HHE) or 4-oxo-2-nonenal (4-ONE) initiate the cellular senescence program of IMR90 fibroblasts and murine adipose stem cells. In such cells, lipid enals induced accumulation of γH2AX foci, increased p53 signaling, enhanced expression of p21Cip1, and upregulated the expression and secretion of numerous cytokines, chemokines, and regulatory factors independently from NF-κB activation. Concomitantly, lipid enal treatment resulted in covalent modification of mitochondrial proteins, reduced mitochondrial spare respiratory capacity, altered nucleotide pools, and increased the phosphorylation of AMP kinase. Lipid-induced senescent cells upregulated BCL2L1 (Bcl-xL) and BCL2L2 (Bcl-w). and were resistant to apoptosis while pharmacologic inhibition of BAX/BAK macropores attenuated lipid-induced senescence. Insitu, the 4-HNE scavenger L-carnosine ameliorated the development of the cellular senescence, while in visceral fat of obese C57BL/6J mice, L-carnosine reduced the abundance of 4-HNE-modified proteins and blunted the expression of senescence biomarkers CDKN1A (p21Cip1), PLAUR, BCL2L1, and BCL2L2. Taken together, the results suggest that lipid enals are endogenous regulators of cellular senescence and that biogenic lipid-induced senescence (BLIS) may represent a mechanistic link between oxidative stress and age-dependent pathologies.

Effect of Gossypol on Gene Expression in Swine Granulosa Cells.

Gossypol (GP), a polyphenolic compound in cottonseed, has notable effects on female reproduction and the respiratory system in pigs. This study aimed to discern the alterations in gene expression within swine granulosa cells (GCs) when treated with two concentrations of GP (6.25 and 12.5 µM) for 72 h, in vitro. The analysis revealed significant changes in the expression of numerous genes in the GP-treated groups. A Gene Ontology analysis highlighted that the differentially expressed genes (DEGs) primarily pertained to processes such as the mitotic cell cycle, chromosome organization, centromeric region, and protein binding. Pathway analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated distinct impacts on various pathways in response to different GP concentrations. Specifically, in the GP6.25 group, pathways related to the cycle oocyte meiosis, progesterone-mediated oocyte maturation, and p53 signaling were prominently affected. Meanwhile, in the GP12.5 group, pathways associated with PI3K-Akt signaling, focal adhesion, HIF-1 signaling, cell cycle, and ECM-receptor interaction showed significant alterations. Notably, genes linked to female reproductive function (CDK1, CCNB1, CPEB1, MMP3), cellular component organization (BIRC5, CYP1A1, TGFB3, COL1A2), and oxidation-reduction processes (PRDX6, MGST1, SOD3) exhibited differential expression in GP-treated groups. These findings offer valuable insights into the changes in GC gene expression in pigs exposed to GP.