Marker Of DNA Damage Research Articles

Temporal and spatial pattern of DNA damage in neurons following spinal cord Injury in mice

BackgroundDeficient DNA repair and excessive DNA damage contribute to neurodegenerative disease. However, the role of DNA damage and repair in spinal cord injury (SCI) is unclear. SCI, a debilitating disruption of the structural and biological network of the spinal cord, is characterized by oxidative stress. Nevertheless, the pathophysiological mechanisms leading to neuronal loss following SCI remain incompletely defined. Methods: Using a contusion model, a severe SCI was induced at the L1 spinal level in C57Bl/6J mice. The temporal and spatial presence of DNA damage was then determined via immunolabeling for the DNA damage marker, γH2AX, from 1 h post-injury (hpi) to 28 days post-injury (dpi). Results: Our analysis revealed that increased DNA damage foci were present from 1 hpi to 3 dpi in SCI mice relative to controls (sham surgery and naive), with the damage signal spreading over time longitudinally from the affected area to more rostral and caudal regions. Co-labeling of γH2AX with NeuN revealed neuronal specificity of DNA damage, with increased early cell death (pan-nuclear γH2AX) peaking at 1 dpi and apoptosis (cleaved Caspase-3) arising later at 3 dpi. Conclusion: Our study indicates a possible role of DNA damage in neuronal loss following SCI and highlights the need for early interventions targeting DNA repair to preserve neuronal tissue.

Short-term exposure of 2.4 GHz electromagnetic radiation on cellular ROS generation and apoptosis in SH-SY5Y cell line and impact on developing chick embryo brain tissue.

Electromagnetic radiation (EMR) from wireless technology and mobile phones, operates at various frequencies. The present study analyses the major impact of short-term exposure to 2.4GHz frequency EMR, using the two model systems chick embryos and SH-SY5Y cell lines. We hypothesized that exposure to this frequency would induce oxidative stress and apoptosis in neurons. Chick embryos were exposed continuously to 2.4GHz EMR for 4h each day over a 5-day period, and comparisons were made with a control group. At the end of the exposure, brain tissues were dissected for histopathological analysis, antioxidant assays, and reactive oxygen species (ROS) detection. Additionally, SH-SY5Y cells were exposed to 2.4GHz EMR to assess cell viability, DNA damage, and apoptosis. Our results showed that exposure to 2.4GHz EMR induces oxidative stress in both chick embryos and the SH-SY5Y cells, though no significant tissue-level impact was observed. In SH-SY5Y cells, ROS production increased after 4h of exposure, accompanied by moderate DNA damage and early markers of apoptosis, such as upregulation of the Bax gene. Furthermore, we observed that antioxidants, such as NAC and Mito-TEMPO, helped mitigate the cytotoxic effects of EMR in both the study models. In conclusion, short-term exposure (4h) to 2.4GHz EMR induced moderate cellular and molecular changes, primarily oxidative stress. The oxidative stress was reduced by antioxidants, which suggests potential benefits in preventing EMR-induced cytotoxicity. Extended exposure to EMR beyond 4h may pose adverse health risks to humans, endorsing further investigation.

Non-Canonical TERT Activity Initiates Osteogenesis in Calcific Aortic Valve Disease.

Calcific aortic valve disease is the pathological remodeling of valve leaflets. The initial steps in valve leaflet osteogenic reprogramming are not fully understood. As TERT (telomerase reverse transcriptase) overexpression primes mesenchymal stem cells to differentiate into osteoblasts, we investigated whether TERT contributes to the osteogenic reprogramming of valve interstitial cells. Human control and calcific aortic valve disease aortic valve leaflets and patient-specific human aortic valve interstitial cells were used in in vivo and in vitro calcification assays. Loss of function experiments in human aortic valve interstitial cells and cells isolated from Tert-/- and Terc-/- mice were used for mechanistic studies. Calcification was assessed in Tert+/+ and Tert-/- mice ex vivo and in vivo. In silico modeling, proximity ligation, and coimmunoprecipitation assays defined novel TERT interacting partners. Chromatin immunoprecipitation and cleavage under targets and tagmentation sequencing defined protein-DNA interactions. TERT protein was highly expressed in calcified valve leaflets without changes in telomere length, DNA damage, or senescence markers, and these features were retained in isolated primary human aortic valve interstitial cells. TERT expression increased with osteogenic or inflammatory stimuli, and knockdown or genetic deletion of TERT prevented calcification in vitro and in vivo. Mechanistically, TERT was upregulated via NF-κB and required to initiate osteogenic reprogramming, independent of its canonical reverse transcriptase activity and the long noncoding RNA TERC. TERT exerts noncanonical osteogenic functions via binding with STAT5 (signal transducer and activator of transcription 5). Depletion or inhibition of STAT5 prevented calcification. STAT5 was found to bind the promoter region of RUNX2 (runt-related transcription factor 2), the master regulator of osteogenic reprogramming. Finally, we demonstrate that TERT and STAT5 are upregulated and colocalized in calcific aortic valve disease tissue compared with control tissue. TERT's noncanonical activity is required to initiate calcification. TERT is upregulated via inflammatory signaling pathways and partners with STAT5 to bind the RUNX2 gene promoter. These data identify a novel mechanism and potential therapeutic target to decrease vascular calcification.

The Selective WEE1 Inhibitor Azenosertib Shows Synergistic Antitumor Activity with KRASG12C Inhibitors in Preclinical Models.

KRAS is a potent oncogenic driver which results in downstream hyperactivation of MAPK signaling, while simultaneously increasing replication stress (RS) and accumulation of DNA damage. KRASG12C mutations are common and targetable alterations. Therapeutic inhibition of KRASG12C and eventual resistance to these inhibitors are also known to drive RS and DNA damage through adaptive mechanisms that maintain addiction to high MAPK signaling. High levels of RS result in a stronger reliance on cell cycle checkpoints, thereby introducing a vulnerability to inhibition of cell cycle checkpoint regulators such as the WEE1 kinase. This provides rationale for combining azenosertib, a novel, selective, and orally bioavailable WEE1 inhibitor, with KRASG12C inhibitors. In vitro combination of azenosertib with multiple KRASG12C inhibitors demonstrated synergistic cell growth inhibition across a panel of KRASG12C cell lines in both 2D and 3D assays. In vivo studies demonstrated azenosertib exhibited significant monotherapy activity as well as synergistic tumor growth inhibition (TGI) when combined with KRASG12C inhibitors, including tumor regression in CDX models of NSCLC, CRC, and PDAC. Importantly, KRASG12C inhibitor-resistant CDX and PDX models demonstrated synergistic TGI in combination arms. Finally, analysis of biomarkers from in vitro and in vivo tumor samples displayed increases in protein markers of RS, DNA damage, and apoptosis after combination treatment. Taken together, our results suggest that the combination of azenosertib with KRASG12C inhibitors enhances tumor growth inhibition over single agent therapy and may be an effective treatment strategy for patients with KRASG12C tumors.

WEE1 Inhibition by AZD1775 Augments Colorectal Cancer Cells Susceptibility to VE-822-induced DNA Damage and Apoptosis.

WEE1 is a key tyrosine kinase involved in the cell cycle regulation with potent anticancer effects in various cancer types including colorectal cancer. Recent studies have focused on the potential of combinational inhibition of Ataxia Telangiectasia and Rad-3-related protein (ATR) and WEE1 in increasing apoptosis in cancer cells. Therefore, this study investigates the effects of inhibiting WEE1, by employing AZD1775, on colorectal cancer cells' susceptibility to VE-822-induced DNA damage and apoptosis.SW-480 and HT-29 cells were treated with AZD1775 and VE-822, alone and in combination. MTT assay was used to assess cell proliferation and viability. The mRNA levels of ATR, checkpoint kinase 1 (CHK1), WEE1, ribonucleotide reductase (RR) catalytic subunit M1 (RRM1) and RRM2 were measured by qRT-PCR. Cellular γ-(H2A histone family member X) H2AX levels were measured by Western blot. Analyses were conducted using ELISA to assess 8-Oxo-2'-deoxyguanosine (8-oxo-dG) levels. Lactate dehydrogenase (LDH) and ELISA death assays were used to assess apoptosis.The SW-480 and HT-29 cells have low proliferation rate when treated with VE-822 and AZD1775. The IC50 value for VE-822 was 1.3 μM and 1.6 μM in SW480 and HT-29, respectively. Also, this value for AZD1775 in SW480 was 140 nM and in HT-29 was 185 nM. The expression levels of ATR, CHK1, WEE1, RRM1, and RRM2 were significantly downregulated in both cell lines treated with combination of VE-822 and AZD1775 (P<0.05). DNA damage markers, including γ-H2AX and 8-oxo-dG were upregulated in these cells. Simultaneous treatment with VE-822 and AZD177 increased apoptosis capacity of both cell lines.The inhibition of WEE1 via AZD1775 potentiated the anticancer effects of ATR inhibitor, VE-822, in combating colorectal cancer via targeting DNA damage.

Targeted Activation of OGG1 Inhibits Paraptosis in Lens Epithelial Cells of Early Age-Related Cortical Cataract.

To investigate potential modes of programmed cell death in the lens epithelial cells (LECs) of patients with early age-related cortical cataract (ARCC) and to explore early-stage intervention strategies. Anterior lens capsules were collected from early ARCC patients for comprehensive analysis. Ultrastructural examination of LECs was performed using transmission electron microscopy. Cell death-associated protein markers were quantified via Western blot analysis, including those for paraptosis (ALIX, GRP78), apoptosis (cleaved caspase 3 and caspase 9), pyroptosis (N-GSDMD), and ferroptosis (GPX4). Intracellular vesicle-organelle colocalization was assessed through immunofluorescence. OGG1 protein expression and activity were evaluated through multiple methods, including Western blot, laser micro-irradiation, and immunofluorescence. The therapeutic potential of the OGG1 activator TH10785 on paraptosis was investigated using an ex vivo rat lens model. Morphologic changes revealed significant endoplasmic reticulum (ER) swelling in ARCC patient LECs, with no characteristic apoptotic features. Paraptosis-related proteins exhibited significant alterations, while other cell death pathway markers (apoptosis, pyroptosis, and ferroptosis) remained unchanged. In the reactive oxygen species-induced paraptosis model, vesicular structures showed exclusive colocalization with ER-specific fluorescence. Elevated levels of the DNA damage marker 7,8-dihydro-8-oxoguanine were observed concurrent with decreased OGG1 activity. The OGG1 activator TH10785 showed efficacy in suppressing LECs paraptosis in ex vivo rat lens cultures. Paraptosis was identified in the LECs of patients with early ARCC. TH10785 activates OGG1 to suppress paraptosis in LECs, suggesting a novel therapeutic approach for early ARCC intervention.

E-cigarettes increase the risk of adenoma formation in murine colorectal cancer model.

E-cigarettes (E.cigs) cause inflammation and damage to human organs, including the lungs and heart. In the gut, E.cig vaping promotes inflammation and gut leakiness. Further, E.cig vaping increases tumorigenesis in oral and lung epithelial cells by inducing mutations and suppressing host DNA repair enzymes. It is well known that cigarette (cig) smoking increases the risk of colorectal cancer (CRC). To date, it is unknown whether E.cig vaping impacts CRC development. A mouse model of human familial adenomatous polyposis (CPC-APC) was utilized wherein a mutation in the adenomatous polyposis coli (APC) gene, CDX2-Cre-APCMin/+, leads to the development of colon adenomas within 11-16weeks. Mice were exposed to air (controls), E.cig vaping, cig, or both (dual exposure). After 4weeks of 2h exposures per day (1h of each for dual exposures), the colon was collected and assessed for polyp number and pathology scores by microscopy. Expression of inflammatory cytokines and cancer stem cell markers were quantified. DNA damage such as double-strand DNA breaks was evaluated by immunofluorescence, western blot, and gene-specific long amplicon qPCR. DNA repair enzyme levels (NEIL-2, NEIL-1, NTH1, and OGG1) were quantified by western blot. Proliferation markers were assessed by RT-qPCR and ELISA. CPC-APC mice exposed to E.cig, cig, and dual exposure developed a higher number of polyps compared to controls. Inflammatory proteins, DNA damage, and cancer stemness markers were higher in E-cig, cig, and dual-exposed mice as well. DNA damage was found to be associated with the suppression of DNA glycosylases, particularly with NEIL-2 and NTH1. E.cig and dual exposure both stimulated cancer cell stem markers (CD44, Lgr-5, DCLK1, and Ki67). The effect of E.cigs on polyp formation and CRC development was less than that of cigs, while dual exposure was more tumorigenic than either of the inhalants alone. E.cig vaping promotes CRC by stimulating inflammatory pathways, mediating DNA damage, and upregulating transcription of cancer stem cell markers. Critically, combining E.cig vaping with cig smoking leads to higher levels of tumorigenesis. Thus, while the chemical composition of these two inhalants, E.cigs and cigs, is highly disparate, they both drive the development of cancer and when combined, a highly common pattern of use, they can have additive or synergistic effects.

Western diet exacerbates a murine model of Balkan nephropathy.

Aristolochic acid (AA) ingestion causes Balkan nephropathy, characterized by tubular injury and progression to chronic kidney disease (CKD). AA is taken up by proximal tubule cells via organic anion transport and induces p21-mediated DNA damage response, but little is known about dietary modulating factors. Western diet (WD) is rich in saturated fats and sugars and can promote metabolic disorders and CKD progression. Here, we determined the impact of WD on AA-induced kidney injury. Five-week-old male C57BL/6J mice were fed WD or normal chow (NC) for 8 wk, followed by administration of AA every 3 days for 3 wk. Measurements were performed after the last injection and following a 3-wk recovery. Independent of dosing AA by body weight (3 mg/kg/day) or same dose/mouse (0.1125 mg/day), the AA-induced increase in plasma creatinine and reduction of hematocrit were greater in WD versus NC. This was associated with increased kidney gene expression in WD vs. NC of markers of DNA damage (p21), injury (Kim1 and Ngal), and inflammation (Tnfa) and kidney fibrosis staining. WD alone increased fractional excretion of indoxyl sulfate by 7.5-fold, indicating enhanced kidney organic anion transport. Kidney proteomics identified further WD-induced changes that could increase kidney sensitivity to AA and contribute to the altered response to AA including weakening of energy metabolism, potentiation of immune and infection pathways, and disruption in RNA regulation. In conclusion, WD can increase the susceptibility of mice to Balkan nephropathy, possibly in part through facilitating kidney uptake of the organic anion AA.NEW & NOTEWORTHY This study shows that a Western diet (WD) aggravates a murine model of Balkan nephropathy induced by the application of the organic anion and nephrotoxin aristolochic acid (AA). Mechanistically, this may involve WD-induced kidney organic anion secretion, which can facilitate the AA uptake into proximal tubular cells and thereby contribute to the injury. Kidney proteomics identified further changes induced by feeding a WD that could have increased the sensitivity of the kidney to stress and injury.

Quantifying DNA Lesions and Circulating Free DNA: Diagnostic Marker for Electropathology and Clinical Stage of AF.

Atrial fibrillation (AF) persistence is associated with molecular remodeling that fuels electrical conduction abnormalities in atrial tissue. Previous research revealed DNA damage as a molecular driver of AF. This study sought to explore the diagnostic value of DNA damage in atrial tissue and blood samples as an indicator of the prevalence of electrical conduction abnormalities and stage of AF. High-sensitivity long-run real-time PCR was performed on mitochondrial (ND1) and nuclear (P53) DNA from atrial tissue samples from paroxysmal (PAF), persistent (PeAF), and longstanding persistent (LS-PeAF) AF, and sinus rhythm (SR) patients (n=83). PicoGreen assay and quantitative polymerase chain reaction were used on circulating free DNA (cfDNA) markers (total cfDNA, β-globin, ND1, and P53) in blood samples of 70 patients with AF or SR. High-resolution epicardial mapping of the atria (n=48) was conducted to quantify electrical conduction abnormalities. The number of DNA lesions gradually and significantly increased in PAF and PeAF and in patients with<3years of AF compared with SR. In SR, the quantity of nuclear DNA damage significantly correlated with the proportion of fractionated potentials. Mitochondrial DNA lesions correlated with slower conduction velocity and lower potential amplitudes in AF samples. Also, mitochondrial cfDNA levels decreased in patients with >3 years of AF compared with<3 years of AF (P=0.004). The quantity of DNA lesions in atrial tissue samples is associated with atrial conduction abnormalities and stage of AF. Serum DNA damage markers discriminate short- from long-term AF. Therefore, the quantity of DNA damage may have diagnostic value in clinical AF management.

Insulin Sensitivity Controls Activity of Pathogenic CD4+ T Cells in Rheumatoid Arthritis.

Hyperinsulinemia connects obesity, and a poor lipid profile, with type 2 diabetes (T2D). Here, we investigated consequences of insulin exposure for T cell function in the canonical autoimmunity of rheumatoid arthritis (RA). We observed that insulin levels correlated with the glycolytic index of CD4+ cells but suppressed transcription of insulin receptor substrates, which was inversely related to insulin sensitivity. This connection between insulin levels and the glycolytic index was not seen in CD4+ cells of healthy controls. Exposure of CD4+ cells to insulin induced a senescent state recognized by cell cycle arrest and DNA content enrichment measured by flow cytometry. It also resulted in accumulation of DNA damage marker γH2AX. Insulin suppressed IFNγ production and induced the senescence-associated secretome in CD4+ cell cultures and in patients with hyperinsulinemia. Inhibition of JAK-STAT signaling (JAKi) improved insulin signaling, which activated the glycolytic index and facilitated senescence in CD4+ cell cultures. Treatment with JAKi was associated with an abundance of naïve and recent thymic emigrant T cells in the circulation of RA patients. Thus, we concluded that insulin exerts immunosuppressive ability by inducing senescence and inhibiting IFNγ production in CD4+ cells. JAKi promotes insulin effects and supports elimination of the pathogenic CD4+ cell in RA patients.

Genetic Ablation of p16 Mitigates Premature Osteoporosis Induced by PTHrP Nuclear Localization Sequence and C-terminal Deletion through Inhibition of Cellular Senescence.

Premature osteoporosis due to parathyroid hormone-related peptide (PTHrP) dysfunction presents significant bone health challenges. This study explores the role of p16-mediated cellular senescence in this condition using a Pthrp knock-in (KI) mouse model lacking the nuclear localization sequence and C-terminus of PTHrP. We generated p16⁻⁄⁻KI mice and compared them with wild-type, p16⁻⁄⁻, and KI mice. The genetic ablation of p16 in KI mice extended their lifespan, increased body size, and weight. Micro-CT analysis revealed a significant increase in bone volume, while histological and immunohistochemical studies revealed enhanced chondrocyte proliferation and osteoblast function in p16⁻⁄⁻KI mice. In vitro experiments showed enhanced differentiation capacity and reduced senescence of bone marrow mesenchymal stem cells (BM-MSCs) from p16⁻⁄⁻KI mice. Molecular analyses indicated that p16 knockout partially reversed oxidative stress, DNA damage, and cellular senescence observed in KI mice, as evidenced by upregulated antioxidant enzymes, reduced DNA damage markers, and decreased senescence markers. These findings highlight the critical role of p16-mediated cellular senescence in the premature osteoporosis phenotype of KI mice, suggesting that targeting cellular senescence pathways could offer a promising therapeutic strategy for premature osteoporosis and age-related bone loss. This research provides new insights into the interplay between genetic factors, cellular senescence, and bone metabolism in the context of aging and osteoporosis.

GATA1 activates HSD17B6 to improve efficiency of cisplatin in lung adenocarcinoma via DNA damage

BackgroundLung adenocarcinoma (LUAD) is the most common histological type of non-small cell lung cancer (NSCLC). Platinum-based chemotherapy, such as cisplatin chemotherapy, is the cornerstone of treatment for LUAD patients. Nevertheless, cisplatin resistance remains the key obstacle to LUAD treatment, for its mechanism has not been fully elucidated.MethodsHSD17B6 mRNA expression data were accessed from TCGA-LUAD database and differential expression analysis was performed. Enrichment analysis of HSD17B6 was conducted by GSEA, and its upstream transcription factors were predicted by hTFtarget. mRNA and protein expression levels of HSD17B6 and GATA1 were assayed by qRT-PCR and WB, and the binding relationship between them was verified by chromatin immunoprecipitation assay and dual luciferase reporter assay. Cell viability and IC50 value of cisplatin-treated cells were measured by cell counting kit-8 assay. Cell cycle was assayed by flow cytometry. DNA damage level and DNA damage marker γ-H2AX expression were assayed by comet assay and western blot, respectively.ResultsHSD17B6 was lowly expressed in LUAD tissues and cells and mainly enriched in homologous recombination and mismatch repair pathways. As cell function experiments revealed, overexpression of HSD17B suppressed malignant phenotypes and cisplatin resistance in LUAD cells through DNA damage. Bioinformatics analysis revealed that GATA1 is the upstream regulator of HSD17B6, which was markedly reduced in LUAD tissues and cells. ChIP and dual luciferase reporter assays ascertained the binding of GATA1 to HSD17B6. Knockdown of GATA1 attenuated the effect of overexpression of HSD17B6 on LUAD cell behaviors and cisplatin resistance.ConclusionTranscription factor GATA1 could activate HSD17B6 to inhibit cisplatin resistance in LUAD through DNA damage, suggesting that GATA1/HSD17B6 axis may be a potential therapeutic target for chemotherapy resistance in LUAD patients.

A Translational Study of the ATR Inhibitor Berzosertib as Monotherapy in Four Molecularly Defined Cohorts of Advanced Solid Tumors.

Preclinical studies have identified molecular correlates of sensitivity to ATR inhibition. This translational study was designed to test the ATR inhibitor berzosertib in patients with advanced solid tumors carrying alterations in ATRX, ATM, genes conferring replication stress (RS), or SDH. Patients were recruited to 4 cohorts: T1: ATRX-mutant leiomyosarcoma; T2: ATM-mutant solid tumors; T3: solid tumors with mutations in RS-associated genes; and T4: SDH-deficient GIST. Patients were treated with berzosertib 240 mg/m2 IV twice per week. Pre and on-treatment biopsies were obtained in cohorts T1-T3. Patients with SDH-mutant GIST had the longest median progression-free survival (PFS) (229 days) with stable disease as the best response. Patients in the other cohorts experienced progressive disease within 4 months. There was no significant difference in PFS comparing outcomes in patients with/without mutations in ATM or RS genes. Decreased pS345-CHK1 in on-treatment biopsies indicated target engagement by berzosertib and were accompanied by substantial increases in levels of DNA damage (g-H2AX) and RS (pKAP1) markers in a subset of patients. However, these biomarker changes did not translate to clinical benefit. In contrast, in cohorts T1-T3, increased expression of SFLN11 on treatment correlated with clinical benefit (HR = 0.045; 95%CI 0.005-0.400). Across cohorts, only SDH-mutant GIST patients experienced prolonged disease control. Despite evidence of target engagement, patients enrolled to all other cohorts had short PFS, suggesting rapid adaptation to ATR inhibitor monotherapy. Among these patients, those with tumors expressing SLFN11 during berzosertib exposure derived the most clinical benefit.

Urine Proteomics in Schistosoma haematobium-induced Bladder Cancer

Schistosomiasis, or Bilharziasis, is a neglected tropical disease caused by Schistosoma parasites, which significantly impacts public health, particularly in Africa. Schistosoma haematobium, the primary species responsible for urogenital schistosomiasis (UGS), is associated with severe chronic conditions, including squamous cell carcinoma (SCC) of the bladder. This review explores the pathogenesis of UGS and its link to bladder cancer, highlighting the molecular mechanisms involved. The chronic inflammation caused by S. haematobium eggs leads to tissue damage, fibrosis, and granuloma formation, creating a pre-cancerous environment. Notably, the role of the p53 pathway in UGS-associated bladder cancer is emphasized, with mutations in the TP53 gene and overexpression of p53 contributing to genetic instability and malignant transformation. Additionally, the review discusses the presence of oestrogen-like metabolites in the urine of UGS patients, which are suspected to be involved in carcinogenesis through an oestrogen-DNA adduct-mediated pathway. Mass spectrometric analysis of urine samples from UGS patients revealed specific metabolites, including 8-oxodG, a marker of oxidative DNA damage, which could serve as potential biomarkers for early detection and progression of bladder cancer. The urine proteome profiling also identified distinct molecular pathways activated in UGS-related bladder cancer, including Th2-type immune responses, oxidative stress, and inflammation. These findings underscore the need for further research into the host-parasite interactions and the development of diagnostic biomarkers for schistosome-induced carcinogenesis. Understanding these mechanisms could enhance treatment strategies and improve prevention efforts for UGS-related bladder cancer, particularly in endemic regions where the disease burden remains high.

State-of-the-art Investigation on the Role of Indium, Terbium, Yttrium, and Lanthanum in Recurrent Pregnancy Loss.

We aimed to explore the role of Indium (In), Terbium (Tb), Yttrium (Y), and Lanthanum (La) in the serum of women with recurrent pregnancy loss (RPL) and compare them to controls. Additionally, the study aimed to examine the relationship between REE levels and oxidative DNA damage, to identify potential risk factors contributing to RPL. This case-control study included 30 RPL cases and 30 controls with uncomplicated pregnancy. Inductively Coupled Plasma Mass Spectrometer was used to evaluate levels of In, Tb, Y, and La in the serum samples in both groups. The relationship between REE levels, Total Antioxidant Capacity (TAC), and DNA damage was studied by correlation analysis. There was a significant increase in levels of In, Tb, Y, and La in the serum of the RPL group in contrast to the control group (P < 0.001). Furthermore, a negative correlation was observed between increased Y, Tb, La, and TAC in RPL cases (significant at P < 0.05), indicative of weakened antioxidant defenses. Moreover, increased levels of Y, Tb, and La exhibited a positive correlation with the DNA damage marker, statistically significant at P < 0.05. These findings highlight the potential role of oxidative stress-induced DNA damage and metal intoxication in the development of RPL, underscoring the importance of further research to clarify underlying mechanisms and develop preventive strategies.

Organophosphate flame retardants associated with increased oxidative stress biomarkers and elevated FeNO levels in general population of children: The Hokkaido study

Our previous study found that exposure to higher organophosphate flame retardants (PFRs) was associated with increased prevalence of wheeze and type 2 inflammation among school-aged children. It remains unclear whether PFR exposure elevates oxidative stress in these general pediatric population, thereby potentially contributing to the development of allergic diseases. This study examined the associations between individual and mixture exposure to PFRs and oxidative stress in children aged 9–12 years (n = 423). The oxidative stress biomarkers included 4-hydroxynonenal (4-HNE) and hexanoyl-lysine (HEL) for lipid peroxidation, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) for DNA damage. We also examined the mediation effects of oxidative stress on the relationships between PFR exposure and health outcomes: wheeze and type 2 inflammation biomarkers, including fraction of exhaled nitric oxide (FeNO) and blood eosinophils. Higher concentrations of tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), Σ triphenyl phosphate (ΣTPHP), Σ tris(2-butoxyethyl) phosphate (ΣTBOEP), and Σ 2-Ethylhexyldiphenyl phosphate (ΣEHDPHP) metabolites were significantly associated with higher levels of 4-HNE. Elevated concentrations of TDCIPP, ΣTPHP, and ΣTBOEP were positively associated with HEL. Higher ΣTPHP and ΣTBOEP were positively associated with 8-OHdG. The PFR mixture was positively associated with all three oxidative stress biomarkers according to the Quantile g-computation and Bayesian kernel machine regression models. Oxidative stress biomarkers mediated 11.4 % to 15.3 % of the association between PFRs and FeNO ≥35 ppb. PFR exposure was positively associated with oxidative stress markers of DNA damage and lipid peroxidation, which may contribute to elevated type 2 inflammation among school-aged children. These findings, identified in the general pediatric population at low exposure levels, highlight the need for ongoing attention to the allergic symptoms posed by PFR exposure.

Network pharmacology‑based analysis and in vitro experimental verification of the inhibitory role of luteoloside on gastric cancer cells via the p53/p21 pathway.

The present study aimed to investigate the inhibitory effect of luteoloside on the proliferation, migration and invasion of gastric cancer (GC) cells based on network pharmacology and in vitro experiments. GC-associated targets were obtained from the GeneCards and Online Mendelian Inheritance in Man databases. Gene Ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed using the Database for Annotation, Visualization and Integrated Discovery. Protein-protein interaction (PPI) networks and herb-active ingredient-target gene-signaling pathway networks were constructed using the Search Tool for the Retrieval of Interacting Genes and proteins and Cytoscape software to analyze core target genes and pathways. In addition, the alkaline comet assay was performed to assess DNA damage, demonstrating that luteoloside induces DNA double-strand breaks in a concentration-dependent manner, as indicated by increased comet tail lengths. γ-H2AX detection through western blot analysis further corroborated these findings, showing significant upregulation of this DNA damage marker in luteoloside-treated GC cells. The human GC cell line NCI-N87 was utilized for in vitro experiments to investigate the impact of different doses of luteoloside on cell proliferation, invasion and migration using Cell Counting Kit-8, scratch-wound and Transwell assays, respectively. The underlying molecular mechanism of luteoloside was explored using western blot analysis. The successfully constructed PPI network revealed the p53, Akt1, Bcl-2 and Caspase-3 proteins as the core targets, all of which showed good binding activity with luteoloside. The in vitro experiments demonstrated that luteoloside treatment significantly inhibited GC-cell proliferation, migration and invasion. The western blot results showed notable concentration-dependent upregulation of p53 and p21 protein expression and downregulation of Bcl-2 protein expression following luteoloside treatment. Overall, luteoloside inhibited the proliferation, migration and invasion of GC cells by activating the p53/p21 signaling pathway.

Selective Inhibition of Cytosolic PARylation via PARG99: A Targeted Approach for Mitigating FUS-associated Neurodegeneration.

Neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) are characterized by complex etiologies, often involving disruptions in functions of RNA/DNA binding proteins (RDBPs) such as FUS and TDP-43. The cytosolic mislocalization and aggregation of these proteins are linked to accumulation of unresolved stress granules (SGs), which exacerbate the disease progression. Poly-ADP-ribose polymerase (PARP)-mediated PARylation plays a critical role in this pathological cascade, making it a potential target for intervention. However, conventional PARP inhibitors are limited by their detrimental effects on DNA repair pathways, which are already compromised in ALS. To address this limitation, we investigated a strategy focused on targeting the cytosolic compartment by expressing the cytosol-specific, natural PAR- glycohydrolase (PARG) isoform, PARG99. Using ALS patient derived FUS mutant induced pluripotent cells (iPSCs) and differentiated neurons, we observed elevated levels of FUS in insoluble fractions in mutant cells compared to mutation-corrected isogenic lines. The insoluble FUS as well as TDP-43 levels increased further in sodium arsenite-treated or oxidatively stressed cells, correlating with accumulation of unresolved SGs. Notably, both PARG99 and PARP inhibitors reduced SG formation and insoluble FUS levels, however, PARG99 treated cells exhibited significantly lower DNA damage markers and improved viability under oxidative and arsenite stress. This study highlights the potential of PARG99 as a cytosol-specific intervention to mitigate FUS-associated toxicity while preserving critical nuclear DNA repair mechanisms, offering a promising strategy for addressing the underlying pathology of ALS and potentially other SG-associated neurodegenerative diseases.

Trichostatin A mitigates acute and late effects of radiation in intestine by regulation of DNA damage repair and Wnt/TGFβ/Smad signaling

Purpose Radiation accidents and misuse of nuclear weapons elevate the risk of development of acute life-threatening injuries as well as their late effects are noted in survivors. Currently, no countermeasure agents are available for the management of radiation-induced GI injury (RIGI) in humans. In the present study, the radiomitigative potential of Trichostatin A (TSA) was evaluated against acute and late RIGI. Methods 15 Gy gamma radiation was delivered to the whole abdomen of C57BL/6 mice, followed by intravenous TSA (150 ng/kg) administration after 1 h and 24 h. Acute changes were checked 24 h and 3.5 days post irradiation. Mice were monitored for development of fibrosis, survival for 1 year and alteration in different signaling pathways. Result 15 Gy abdominal irradiation activated the DNA damage marker (γ-H2AX) by nearly 3.2 ± 0.29 fold and regulated the repair proteins, XRCC1 and PARP1 in the intestine, which was differentially regulated by TSA. The Wnt signaling pathway and stem cell proliferation in the intestine were also positively regulated by TSA. The TSA administered mice demonstrated improved intestinal morphology. 12.5% of TSA administered mice survived upto 1 year whereas 100% of 15 Gy exposed mice died by 6 months. The surviving mice that had received TSA showed reduced intestinal fibrosis than 15 Gy group, possibly via downregulation of TGFβ/Smad signaling. Conclusion The findings suggest that TSA have the potential to mitigate both acute and late effects of radiation in the intestine and can be explored as promising agent in the management of RIGI.

Protective effect of ginseng berry saponin conversion products on skin photodamage caused by UVB in vitro and in vivo

Ultraviolet (UV) B irradiation is closely related to skin aging and skin damage. Here, we report the photoprotective mechanism of action of ginseng berry rare saponins (GFRS) on UVB-induced damage to human keratinocytes and mouse skin. Several UVB irradiation–induced cytotoxicity and oxidative stress responses were assessed. GFRS preconditioning significantly improved HaCaT cell survival and reduced the levels of the DNA damage markers histone H2AX and cyclobutane pyrimidine dimer. Under oxidative stress, GFRS could reduce the transformation and loss of the mitochondrial membrane potential to the monomer form; effectively clear the expression of lipid reactive oxygen species, malondialdehyde, and other peroxides, and restore total superoxide dismutase, glutathione peroxidase, and catalase levels. The occurrence of ferroptosis after UVB induction was also studied. Erastin exacerbated the induced cellular iron overload, whereas GFRS and Fer-1 reversed this response to varying degrees. Mechanistically, GFRS activated the Nrf2/HO-1/GPX4 pathway and inhibited the phenomenon of ferroptosis in cells. Our findings were confirmed using a mouse model of UV induced skin injury. GFRS not only mitigated lipid peroxides and iron overload in tissues but also prevented skin barrier damage and collagen loss. Therefore, GFRS shows potential as a novel functional product as it protects the skin from UVB light–induced damage.