OBJECTIVES: To investigate the effects of hyperoxia on the expression of N-methyl-D-aspartate receptor 1 (NMDAR1) and its synapse-associated molecules, including cannabinoid receptor 1 (CB1R), postsynaptic density 95 (PSD95), and synapsin (SYN), in the hippocampus of neonatal rats. METHODS: One-day-old Sprague-Dawley neonatal rats were randomly divided into a hyperoxia group and a control group (n=8 per group). The hyperoxia group was exposed to 80% ± 5% oxygen continuously, while the control group was exposed to room air, for 7 days. At 1, 3, and 7 days after hyperoxia exposure, hematoxylin and eosin (HE) staining was used to observe histopathological changes in the brain. The expression levels of NMDAR1, CB1R, PSD95, and SYN proteins and mRNAs in the hippocampus were detected by immunohistochemistry, Western blotting, and quantitative real-time PCR. RESULTS: After 7 days of hyperoxia exposure, the hyperoxia group showed decreased neuronal density and disordered arrangement in brain tissue. Compared with the control group, after 1 day of hyperoxia exposure, CB1R mRNA and both NMDAR1 and CB1R protein expression in the hyperoxia group were significantly downregulated, while SYN protein expression was significantly upregulated (P<0.05). After 3 days, mRNA expression of NMDAR1, CB1R, and SYN was significantly decreased (P<0.05); NMDAR1 and CB1R protein expression was significantly downregulated (P<0.05), while PSD95 and SYN protein expression was significantly upregulated (P<0.05). After 7 days of hyperoxia, the protein expression of NMDAR1 and CB1R was significantly upregulated (P<0.05). CONCLUSIONS Continuous hyperoxia exposure induces time-dependent changes in the expression levels of NMDAR1 and its synapse-associated molecules in the hippocampus of neonatal rats.
Animals ; Receptors, N-Methyl-D-Aspartate/genetics* ; Rats, Sprague-Dawley ; Hippocampus/pathology* ; Rats ; Animals, Newborn ; Receptor, Cannabinoid, CB1/genetics* ; Hyperoxia/metabolism* ; Disks Large Homolog 4 Protein/genetics* ; Synapsins/genetics* ; Synapses ; Male ; Female ; RNA, Messenger/analysis*

OBJECTIVE: To study the expression of SPOP in patients with acute myeloid leukemia (AML) and its effect on proliferation, apoptosis and cycle of AML cells. METHODS: RT-qPCR was used to detect the expression of SPOP mRNA in bone marrow samples of patients with newly diagnosed AML and normal controls. The stable overexpression of SPOP in AML cell lines THP-1 and U937 were constructed by liposome transfection. The effect of SPOP on cell proliferation was detected by CCK-8, and the effect of SPOP on apoptosis and cell cycle was detected by flow cytometry. The expressions of anti-apoptotic protein Bcl-2 and apoptotic protein Bax, Caspase3 were detected by Western blot. RESULTS: The median expression level of SPOP mRNA in normal control group was 0.993 1(0.6303, 1.433), while that in AML group was 0.522 1(0.242 2, 0.723 7). The expression level of SPOP in AML group was significantly lower than that in normal control group ( P < 0.001). After the overexpression of SPOP, the proportion of apoptotic cells in the U937 overexpression group and THP-1 overexpression group was 10.9%±0.3% and 4.6%±015%, which were higher than 8.9%±0.3% and 3.0%±0.30% in the Empty Vector group, respectively (both P < 0.05). The expression of Caspase3 in U937 overexpression group and THP-1 overexpression group was 1.154±0.086 and 1.2±0.077, which were higher than 1 in Empty Vector group, respectively (both P < 0.05). The ratio of Bax/Bcl-2 in U937 overexpression group and THP-1 overexpression group was 1.328±0.057 and 1.669±0.15, which were higher than 1 in Empty Vector group, respectively (both P < 0.05). In the cell proliferation experiment, the number of cells in the U937 overexpression group and THP-1 overexpression group were both slightly lower than those in the Empty Vector group, but the differences were not statistically significant (P >0.05). In the cell cycle experiment, the proportion of G₁ cells in the U937 overexpression group and THP-1 overexpression group were both slightly higher than those in the Empty Vector group, but the differences were not statistically significant (P >0.05). CONCLUSION SPOP can promote the apoptosis of leukemic cells, and its mechanism may be related to down-regulation of Bcl-2 expression and up-regulation of Bax and Caspase3 expression.
Humans ; Leukemia, Myeloid, Acute/pathology* ; Apoptosis ; Repressor Proteins/genetics* ; Cell Proliferation ; Nuclear Proteins/genetics* ; Cell Cycle ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Caspase 3/metabolism* ; bcl-2-Associated X Protein/metabolism* ; U937 Cells ; Cell Line, Tumor ; RNA, Messenger/genetics*

OBJECTIVE: To screen novel diagnostic marker or therapeutic target for multiple myeloma (MM). METHODS: Sel1L, SPAG4, KCNN3 and PARM1 were identified by bioinformatics method based on GEO database as high expression genes in MM. Their RNA and protein expression levels in bone marrow mononuclear cells from myeloma cell lines U266, NCI-H929, MM.1s, RPMI8226 and leukemia cell line THP1, as well as 31 MM patients were evaluated by RT-PCR and Western blot, respectively. Meanwhile, 5 samples of bone marrow from healthy donors for allogeneic hematopoietic stem cell transplantation were employed as controls. RESULTS: Compared with leukemia cell line THP1, the expression levels of KCNN3, PARM1 and Sel1L mRNA were significantly increased in myeloma cell lines U266, NCI-H929 and MM.1s, while PARM1 was further increased in myeloma cell lines 8226. Western blot showed that the 4 genes were all expressed in the 4 myeloma cell lines. Compared with healthy controls, the expression levels of Sel1L, SPAG4, KCNN3 and PARM1 mRNA were significantly higher in MM patients (all P < 0.05). Western blot showed that the 4 genes were all expressed in MM patients, and the protein expression level of Sel1L and KCNN3 were significantly different compared with healthy donors (all P < 0.01). CONCLUSION Sel1L, SPAG4, KCNN3 and PARM1 may be potential diagnostic markers and therapeutic targets for MM.
Humans ; Multiple Myeloma/genetics* ; Cell Line, Tumor ; Proteins/metabolism* ; Computational Biology ; RNA, Messenger/genetics*

OBJECTIVE: To investigate the expression of RNA binding protein ELAVL1 in prostate cancer (PCa), especially hormone-sensitive prostate cancer (HSPC), and its relationship with tumor proliferation. This study further aims to reveal the molecular mechanism by which ELAVL1 promotes HSPC proliferation by stabilizing SOX4 mRNA in an m6A-dependent manner. METHODS: The expression of ELAVL1 in PCa tissues and its relationship with prognosis were analyzed in the Cancer Genome Atlas (TCGA) database, and the differences in HSPC and hormone-resistant prostate cancer (HRPC) were compared. And its relationship with prognosis were analyzed in the Cancer Genome Atlas (TCGA) database, and the differences in HSPC and hormone-resistant prostate cancer (HRPC) were compared. Western blot was used to detect ELAVL1 protein expression in PCa cell lines. After ELAVL1 knockdown by siRNA, cell proliferation was evaluated using CCK-8 assays, and changes in downstream target genes were detected by RT-qPCR. Tumor xenograft experiments in nude mice were performed to further assess the impact of ELAVL1 on tumor growth. The interaction between ELAVL1 and SOX4 mRNA was verified by RIP-seq. And the mRNA and protein levels of SOX4 after knockdown of ELAVL1 were detected by RT-qPCR and Western blot, respectively. CCK-8 was used to evaluate the effect of SOX4 knockdown on cell proliferation. MeRIP-qPCR was used to detect the m6A modification level of SOX4 and the effect of knocking down METTL3. RNA pull-down experiments verified the interaction between SOX4 RNA fragments and ELAVL1 protein. RNA stability experiments evaluated the effect of ELAVL1 knockdown on SOX4 mRNA stability. RESULTS: The expression of ELAVL1 in PCa cells was higher than that in normal prostate epithelial cells. The prognosis of patients with high expression of ELAVL1 was significantly worse than that of patients with low expression. In the GSE32269 dataset, the expression level of ELAVL1 in HSPC was significantly higher than that in HRPC. After knocking down of ELAVL1 in LNCaP and VCaP cells, CCK-8 experiments showed that the cell proliferation ability was significantly affected after knocking down ELAVL1, and overexpressed ELAVL1 promoted the proliferation of HSPC cells. The results of in vivo studies showed that knockdown of ELAVL1 significantly inhibited the tumorigenic capacity of LNCaP cells and resulted in a marked reduction in xenograft tumor mass. The levels of SOX4 mRNA and protein in LNCaP and VCaP cells were significantly higher than those in normal prostate epithelial cells RWPE-1. RIP-qPCR confirmed the interaction between ELAVL1 protein and SOX4 mRNA. After knocking down of ELAVL1, the expression levels of SOX4 mRNA and protein were significantly decreased. After knocking down of SOX4, the proliferation ability of LNCaP and VCaP cells was significantly inhibited. CONCLUSION ELAVL1 is highly expressed in HSPC. High expression of ELAVL1 is associated with the proliferation of HSPC. SOX4 is a downstream molecule of ELAVL1 which promotes the proliferation of HSPC. ELAVL1 enhances the stability of SOX4 mRNA through an m6A-dependent mechanism.
Male ; Humans ; SOXC Transcription Factors/genetics* ; ELAV-Like Protein 1/metabolism* ; Cell Proliferation ; Prostatic Neoplasms/genetics* ; Animals ; Mice, Nude ; Cell Line, Tumor ; Mice ; Gene Expression Regulation, Neoplastic ; RNA, Messenger/metabolism* ; Prognosis

OBJECTIVE: To initially investigate the function of neuronal pentraxin 1 (NPTX1) gene on osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). METHODS: hBMSCs were induced to undergo osteogenic differentiation, and then RNA was collected at different time points, namely 0, 3, 7, 10 and 14 d. The mRNA expression levels of key genes related with osteogenic differentiation, including runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN), and NPTX1, were detected on the basis of quantitative real-time polymerase chain reaction (qPCR) technology. In order to establish a stable NPTX1-knockdown hBMSCs cell line, NPTX1 shRNA lentivirus was constructed and used to infect hBMSCs. ALP staining, alizarin red (AR) staining, and qPCR were employed to assess the impact of NPTX1-knockdown on the osteogenic differentiation ability of hBMSCs. RESULTS: The results showed that during the osteogenic differentiation of hBMSCs in vitro, the mRNA expression levels of osteogenic genes RUNX2, ALP and OCN significantly increased compared with 0 d, while NPTX1 expression decreased markedly (P < 0.01) as the osteogenic induction period exten-ded. At 72 h post-infection with lentivirus, the result of qPCR indicated that the knockdown efficiency of NPTX1 was over 60%. After knocking down NPTX1 in hBMSCs, RNA was extracted from both the NPTX1-knockdown group (sh NPTX1 group) and the control group (shNC group) cultured in regular proliferation medium. The results of qPCR showed that the expression levels of osteogenic-related genes RUNX2 and osterix (OSX) were significantly higher in the sh NPTX1 group compared with the shNC group (P < 0.01). ALP staining revealed a significantly deeper coloration in the sh NPTX1 group than in the shNC group at the end of 7 d of osteogenic induction. AR staining demonstrated a marked increase in mineralized nodules in the sh NPTX1 group compared with the shNC group at the end of 14 d of osteogenic induction. CONCLUSION NPTX1 exerts a modulatory role in the osteogenic differentiation of hBMSCs, and its knockdown has been found to enhance the osteogenic differentiation of hBMSCs. This finding implies that NPTX1 could potentially serve as a therapeutic target for the treatment of osteogenic abnormalities, including osteoporosis.
Humans ; Mesenchymal Stem Cells/cytology* ; Osteogenesis/genetics* ; Cell Differentiation/genetics* ; Nerve Tissue Proteins/genetics* ; Cells, Cultured ; C-Reactive Protein/genetics* ; RNA, Small Interfering/genetics* ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Bone Marrow Cells/cytology* ; Gene Knockdown Techniques ; Osteocalcin/metabolism* ; Alkaline Phosphatase/metabolism* ; RNA, Messenger/metabolism*

OBJECTIVE: It has been reported that the mRNA expression of serine protease 23 (PRSS23) was increased in skin fibroblasts from systemic sclerosis patients (SSc). The purpose of this study is to explore the pathogenetic effect and mechanism of PRSS23 in skin fibrosis of SSc. METHODS: The expression of PRSS23 in skin tissues from the SSc patients and healthy controls was detected by immunohisto-chemistry. Fibroblasts isolated from fresh skin tissue were used to detect the expression of PRSS23 by real-time quantitative PCR (RT-qPCR) and Western blot. Overexprssion of PRSS23 in BJ, the fibroblasts cell line of skin, was constructed by lentivirus. After stimulation with 400 μmol/L hydrogen peroxide for 12 h, Annexin V/7-AAD staining was used to detect apoptosis of fibroblasts; flow cytometry and Western blot were used to detect the expression of apoptosis-related protein cleaved Caspase-3. The expression of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) in fibroblasts was detected by RT-qPCR and enzyme linked immunosorbent assay (ELISA). RESULTS: Compared with the healthy controls, the expression of PRSS23 in skin tissues of the SSc patients was significantly increased [4.952 (3.806-5.439) vs. 0.806 (0.395-1.173), P < 0.001], and fibroblast was the main cell that expressed PRSS23. The mRNA [27.59 (25.02-30.00) vs. 1.00, P < 0.001] and protein [0.675 (0.587-0.837) vs. 0.451 (0.342-0.502), P=0.029] of PRSS23 in skin fibroblasts isolated from the SSc patients were significantly up-regulated. Compared with the control group, the anti-apoptotic ability of skin fibroblasts overexpressing PRSS23 was enhanced, and the proportion of apoptotic cells was significantly reduced after hydrogen peroxide induction [(5.043±1.097)% vs. (17.480±3.212)%, P=0.022], the expression of apoptosis-related protein cleaved Caspase-3 was also markedly reduced [(0.718±0.022) vs. (1.422±0.105), P=0.003]. In addition, the mRNA [(99.780±1.796) vs. (1.000±0.004), P < 0.001] and protein [(211.600±2.431) ng/L vs. (65.930±1.768) ng/L, P < 0.001] of IL-6 in the fibroblasts overexpressing PRSS23 were significantly up-regulated; the mRNA[(3.555±0.555) vs. (1.000±0.004), P < 0.001] and protein levels [(41.190±0.949) ng/L vs. (31.150±0.360) ng/L, P < 0.001] of TNF-α in the fibroblasts overexpressing PRSS23 were also significantly up-regulated. CONCLUSION The expression of PRSS23 is increased in skin fibroblasts of SSc patients. PRSS23 can inhibit cell apoptosis, promote the secretion of inflammatory factors such as IL-6 and TNF-α, and regulate the process that skin fibroblasts transform into pro-inflammatory type. So, PRSS23 is associated with the development of skin fibrosis.
Humans ; Scleroderma, Systemic/enzymology* ; Fibroblasts/pathology* ; Apoptosis ; Skin/metabolism* ; Fibrosis ; Interleukin-6/metabolism* ; Caspase 3/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Male ; Female ; Cells, Cultured ; RNA, Messenger/metabolism* ; Middle Aged ; Adult ; Serine Endopeptidases/genetics*

OBJECTIVES: To investigate the expression of parathyroid hormone-like hormone (PTHLH) in hepatocellular carcinoma (HCC) and analyze its correlation with clinical prognosis, its regulatory effects on HCC cell behaviors, and the signaling pathways mediating its effects. METHODS: We analyzed the differential expression of PTHLH in HCC and adjacent tissues and its association with patient prognosis based on data from TCGA and GEO databases and from 70 HCC patients treated in our hospital. The effects of PTHLH knockdown and overexpression on proliferation, migration, and invasion of cultured HCC cells were investigated using CCK-8 assay, colony formation assay, Transwell migration and invasion assays, and the signaling pathways activated by PTHLH were detected using Western blotting. RESULTS: TCGA and GEO database analysis showed significant overexpression of PTHLH mRNA in HCC tissues, which was associated with poor prognosis of the patients (P<0.05). High PTHLH mRNA expression was a probable independent prognostic risk factor for HCC (P<0.05). In the clinical samples, PTHLH mRNA and protein expressions were significantly higher in HCC tissues than in the adjacent tissues (P<0.001 or 0.01). Univariate and multivariate Cox regression analyses suggested that high PTHLH mRNA expression was an independent risk factor to affect postoperative disease-free survival of HCC patients (P<0.05). The prognostic prediction model based on PTHLH mRNA expression showed an improved accuracy for predicting the risk of postoperative recurrence in HCC patients. In cultured HCC cells, PTHLH overexpression significantly promoted cell proliferation, colony formation, migration and invasion, and caused activation of the ERK/JNK signaling pathway in Huh7 and Hep3B cells. CONCLUSIONS High PTHLH expression promotes HCC progression and is associated with poor patient prognosis. Its pro-tumor effects may be mediated by activation of the ERK/JNK signaling pathway.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Prognosis ; Cell Proliferation ; Parathyroid Hormone-Related Protein/genetics* ; Cell Line, Tumor ; Cell Movement ; Disease Progression ; Signal Transduction ; Male ; RNA, Messenger/genetics* ; Female

During the hyperacute phase of intracerebral hemorrhage (ICH), the mass effect and blood components mechanically lead to brain damage and neurotoxicity. Our findings revealed that the mass effect and transferrin precipitate neuronal oxidative stress and iron uptake, culminating in ferroptosis in neurons. M6A (N6-methyladenosine) modification, the most prevalent mRNA modification, plays a critical role in various cell death pathways. The Fto (fat mass and obesity-associated protein) demethylase has been implicated in numerous signaling pathways of neurological diseases by modulating m6A mRNA levels. Regulation of Fto protein levels in neurons effectively mitigated mass effect-induced neuronal ferroptosis. Applying nanopore direct RNA sequencing, we identified voltage-dependent anion channel 3 (Vdac3) as a potential target associated with ferroptosis. Fto influenced neuronal ferroptosis by regulating the m6A methylation of Vdac3 mRNA. These findings elucidate the intricate interplay between Fto, Vdac3, m6A methylation, and ferroptosis in neurons during the hyperacute phase post-ICH and suggest novel therapeutic strategies for ICH.
Ferroptosis/physiology* ; Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics* ; Animals ; Neurons/metabolism* ; Transferrin/pharmacology* ; Mice ; Methylation ; Mice, Inbred C57BL ; Adenosine/metabolism* ; RNA, Messenger/metabolism* ; Male ; Oxidative Stress/physiology*

OBJECTIVE: To explore the role of CDGSH iron-sulfur domain 2 (CISD2) in patients with sepsis-related myocardial injury (SMI) and its predictive value for 28-day prognosis and myocardial damage through clinical studies and cell experiments. METHODS: A retrospective study was conducted. Adult patients diagnosed with sepsis admitted to the critical care medicine of Third Affiliated Hospital of Qiqihar Medical University from January 2023 to January 2024 were enrolled. The clinical data, laboratory indicators, expression level of CISD2 mRNA in peripheral blood mononuclear cells (PBMC) 24 hours after admission, and 28 days prognosis were collected. Patients were divided into SMI group [left ventricular ejection fraction (LVEF) < 0.50 or LVEF decreased by ≥ 10% from baseline] and sepsis non-myocardial injury group based on LVEF. The expression levels of CISD2 mRNA were compared between the two groups, and the correlation between CISD2 and myocardial injury was analyzed. Patients were divided into the low-expression group (CISD2 mRNA < 0.5 copy/μL) and the high-expression group (CISD2 mRNA ≥ 0.5 copy/μL) based on the expression of CISD2 mRNA, and into the survival group and the death group based on the prognosis at 28 days. The clinical characteristics were analyzed between the groups. Multivariate Logistic regression was used to analyze the independent predictors of 28-day mortality in patients with sepsis. The predictive value of CISD2 for myocardial damage and 28-day prognosis in patients with sepsis were evaluated by using the receiver operator characteristic curve (ROC curve). In addition, in vitro experiments using human AC16 cardiomyocytes was conducted. The cells were divided into control group, lipopolysaccharide (LPS) group, the LPS+transfection group with overexpression of CISD2 plasmid (LPS+p-CISD2 group), and the LPS + transfection group with negative control plasmid (LPS+p-NC group). The mRNA expression of CISD2 in cells were detected by real-time quantitative polymerase chain reaction (RT-qPCR), the protein expression of CISD2 in cells were detected by Western blotting, and the cell viability was determined by cell counting kit-8 (CCK-8). RESULTS: A total of 85 sepsis patients were included, with 32 developing myocardial injury and 53 without myocardial injury. There were 40 cases of low expression of CISD2 and 45 cases of high expression of CISD2. At 28 days, 60 cases survived and 25 cases died. The mRNA expression of CISD2 in the SMI group was significantly lower than that in the sepsis non-myocardial injury group (copy/μL: 0.41±0.09 vs. 0.92±0.13, P < 0.05). CISD2 was significantly correlated with myocardial injury in patients with sepsis (r = 0.729, P < 0.05). The proportion of LVEF < 0.50 (67.50% vs. 11.11%), sequential organ failure score (SOFA: 15.63±2.15 vs. 11.12±1.52), and acute physiology and chronic health evaluation II (APACHEII: 29.49±3.51 vs. 22.41±2.61) in the CISD2 low-expression group were significantly higher than those in the CISD2 high-expression group (all P < 0.05), while there were no significantly differences in other indicators. The Kaplan-Meier survival curve showed that the 28-day survival time of sepsis patients with in the CISD2 low-expression group was significantly shorter than that in the CISD2 high-expression group (Log-rank test: χ ² = 5.601, P < 0.05). The proportion of CISD2 low-expression and the proportion of LVEF < 0.50 in the survival group were both higher than those in the death group (80.00% vs. 33.33%, 64.00% vs. 26.67%, both P < 0.05), while there were no significantly differences in other indicators. Multivariate Logistic regression analysis showed that CIDS2 and LVEF were independent predictive factors for 28-day mortality in patients with sepsis [CIDS2: odds ratio (OR) = 3.400, 95% confidence interval (95%CI) was 1.026-11.264, P = 0.045; LVEF: OR = 2.905, 95%CI was 1.029-8.199, P = 0.044]. ROC curve analysis showed that when CISD2 was expressed at a low level, patients with sepsis were at high risk of death within 28 days and myocardial injury. The sensitivity of CISD2 in predicting the 28-day mortality of patients with sepsis was 80.00%, and the specificity was 66.67%, and the area under the curve (AUC) was 0.733 (95%CI was 0.626-0.823). The sensitivity of CISD2 in predicting myocardial injury in patients with sepsis was 83.87%, the specificity was 74.07%, and the AUC was 0.790 (95%CI was 0.688-0.871). In addition, compared with the control group, the mRNA and protein expressions of CISD2 as well as the cell activity in the LPS group were significantly decreased. The mRNA and protein expressions of CISD2 and the activity of cardiomyocytes transfected with p-CISD2 were significantly increased. CONCLUSIONS CISD2 plays a protective role in sepsis-associated myocardial injury and has good predictive value for 28-day prognosis and myocardial injury.
Humans ; Sepsis/metabolism* ; Prognosis ; Retrospective Studies ; Male ; Female ; Middle Aged ; RNA, Messenger/genetics* ; Aged ; Myocardium/metabolism*

OBJECTIVES: This study aims to explore the potential relationships of cell-free DNA (cfDNA) in gingival crevicular fluid (GCF) with periodontal clinical indicators and the expression of DNA receptor pathway cyclic guanosine phosphate-adenosine phosphate synthase (cGAS)-stimulator of interferon genes (STING) in gingival tissues and human gingival fibroblasts (HGFs). METHODS: GCF and gingival tissue samples were collected from periodontally healthy individuals and patients diagnosed with periodontitis. Periodontal clinical indicators were recorded, including plaque index (PLT), bleeding index (BI), probing depth (PD), and clinical attachment level (CAL). The concentration of cfDNA in GCF was quantified, and the correlation between GCF and periodontal clinical indicators was analyzed. Immunofluorescence and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to assess the distribution of cGAS, STING, and p-STING in gingival tissues. Additionally, the mRNA expression levels of the key components of the cGAS-STING signaling pathway, namely, cGAS, STING, inhibitory of kappa-B kinase (IKK), nuclear factor kappa-B p65 (NF-κB p65), interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α), were measured. Furthermore, cfDNA extracted from GCF was employed to stimulate HGFs in the healthy control and periodontitis groups, and the mRNA expression levels of the key molecules of cGAS-STING signaling pathway were detected through Western blot and RT-qPCR. RESULTS: The concentration of cfDNA in GCF was found to be significantly elevated in the periodontitis group compared with the control group. Moreover, cfDNA concentration demonstrated a strong positive correlation with the periodontal clinical indicators. Immunofluorescence analysis revealed considerably increased percentage of fluorescence co-localization of cGAS, STING, and p-STING with the gingival fibroblast FSP-1 marker in the gingival tissues of the periodontitis group. The mRNA expression levels of cGAS, STING, IKK, NF-κB p65, IL-1β, IL-6,and TNF-α were significantly higher in the periodontitis group. In vitro stimulation of HGFs with GCF-derived cfDNA resulted in increased protein expression of cGAS and p-STING and considerably upregulated the mRNA expression levels of cGAS, STING, IKK, NF-κB p65, IL-1β, IL-6, and TNF-α in the healthy and periodontitis groups compared with the blank group. Correlation analysis showed that the concentration of cfDNA at the sampling site was positively correlated with the mRNA expression levels of cGAS, STING, NF-κB p65, and IL-6 in gingival tissues. CONCLUSIONS cfDNA concentrations in the GCF of patients with periodontitis are considerably elevated, and are associated with the activation of the cGAS-STING signaling pathway in HGFs. These findings suggest that cfDNA contributes to the progression of periodontitis.
Humans ; Gingival Crevicular Fluid/metabolism* ; Signal Transduction ; Gingiva/cytology* ; Nucleotidyltransferases/genetics* ; Membrane Proteins/genetics* ; Cell-Free Nucleic Acids/analysis* ; Fibroblasts/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Periodontitis/metabolism* ; Interleukin-1beta/metabolism* ; Interleukin-6/metabolism* ; Adult ; RNA, Messenger/metabolism* ; Male ; Female