Objective To elucidate the molecular mechanism of sirtuin-3 (SIRT3) in regulating mitochondrial biogenesis in human renal tubular epithelial cells. Methods Cells were stimulated with different concentrations of H₂O₂ and divided into four groups: control (NC), 50 μmol/L H₂O₂, 110 μmol/L H₂O₂ and 150 μmol/L H₂O₂. SIRT3 protein expression was then measured. SIRT3 was knocked down with siRNA, and cells were further assigned to five groups: control (NC), negative-control siRNA (NCsi), SIRT3-siRNA (siSIRT3), NCsi+H₂O₂, and siSIRT3+H₂O₂. After 24 h, cellular adenosine triphosphate (ATP) and mitochondrial superoxide anion (O₂•⁻) levels were determined, together with mitochondrial expression of SIRT3, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF1), mitochondrial transcription factor A (TFAM), superoxide dismutase 2 (SOD2), acetylated-SOD2 and adenosine monophosphate activated protein kinase α1 (AMPKα1). Results The 110 and 150 μmol/L H₂O₂ decreased SIRT3 protein (both P<0.05). ATP and mitochondrial O₂•⁻ did not differ between NC and NCsi groups (both P>0.05). Compared to the NCsi group, the siSIRT3 group exhibited elevated O₂•⁻ level, decreased SIRT3 protein and increased expression levels of SOD2 and acetylated SOD2 protein (all P<0.05). Compared to the NCsi group, the NCsi+H₂O₂ group exhibited decreased cellular ATP levels, elevated mitochondrial O₂•⁻ levels, and reduced protein expression levels of SIRT3, SOD2, TFAM, AMPKα1, PGC-1α and NRF1 (all P<0.05). Compared with the siSIRT3 group, the siSIRT3+H₂O₂ group showed a decrease in cellular ATP levels, an increase in mitochondrial O₂•⁻ levels, a decrease in SIRT3, SOD2, TFAM, AMPKα1, PGC-1α and NRF1 protein expression levels and a decrease in acetylated SOD2 protein expression levels (all P<0.05). Compared with the NCsi+H₂O₂ group, the siSIRT3+H₂O₂ group showed a decrease in cellular ATP levels, an increase in mitochondrial O₂•⁻ levels, a decrease in SIRT3, AMPKα1, PGC-1α and NRF1, TFAM protein expression levels, and an increase in SOD2 and acetylated SOD2 protein expression levels (all P<0.05). Conclusions SIRT3 promotes mitochondrial biogenesis in tubular epithelial cells via the AMPK/PGC-1α/NRF1/TFAM axis, representing a key mechanism through which SIRT3 ameliorates oxidative stress-induced mitochondrial dysfunction.

Objective To investigate the role of the O-6-methylguanine-DNA methyltransferase (MGMT) gene-3′ untranslated region (UTR) microRNA-associated single nucleotide polymorphism (miRSNP) (rs7896488 G>A) in affecting miR-4297-targeted modulation of MGMT in senescence of lung cells with polymorphic genotypes induced by fractionated low dose ionizing radiation (LDIR). Methods i) MiRSNPs were predicted and screened using bioinformatics, and DNA from two types of lung cells, A549 cells and human bronchial epithelioid cells (HBE cells), was extracted for target gene sequencing. After co-transfection of pGL3c-MGMT-3′UTR-rs7896488 G>A reporter gene recombinant plasmid, pRL-TK Vector with micrON mimic NC #22 or micrON hsa-miR-4297 mimic (set up as the mimic NC group and the miR-4297 mimic group) in these two types of lung cells, dual luciferase reporter gene assay was performed. The relative expression of MGMT mRNA was detected by real-time fluorescence quantitative polymerase chain reaction, and the relative expression of MGMT protein was detected by Western blotting. ii) These two types of lung cells were randomly divided into the control group and irradiation group, which received either 0 or 100 mGy X-rays irradiation seven times. After irradiation, the cells were transfected with either micrON mimic NC #22 or micrON hsa-miR-4297 mimic, resulting in mimic NC + control group, miR-4297 mimic + control group, mimic NC + irradiation group, and miR-4297 mimic + irradiation group. Cells were collected for senescence-associated-β-galactosidase (SA-β-Gal) staining, and the relative expression of matrix metalloproteinase-9 (MMP-9) and chemokine (C-X-C motif) ligand-1 (CXCL-1) proteins was detected via Western blotting. Results i) The rs7896488 G>A was the miRSNP located in the conserved binding region targeted by miR-4297 in the MGMT gene 3′UTR. A549 cells were the rs7896488 GG wild-type homozygous genotype, while HBE cells were the rs7896488 GA heterozygous mutant genotype. In the miR-4297 mimic group, A549 and HBE cells carrying the rs7896488 G allele showed significantly lower dual-luciferase activity compared with that in the mimic NC group (both P<0.01). However, there was no significant difference in dual-luciferase activity between the two groups in both A549 and HBE cells carrying the rs7896488 A allele (both P>0.05). The relative expression levels of MGMT mRNA and MGMT protein of A549 cells in the miR-4297 mimic group were lower than those in the mimic NC group (both P<0.05). However, there was no significant difference in MGMT mRNA and MGMT protein of HBE cells between these two groups (both P>0.05). ii) The relative activity of SA-β-Gal and the relative expression of MMP-9 and CXCL-1 proteins of A549 cells in the miR-4297 mimic+irradiation group were higher than those in the mimic NC + control group, the miR-4297 mimic + control group, and the mimic NC + irradiation group (all P<0.05). The relative activity of SA-β-Gal and the relative expression of MMP-9 and CXCL-1 proteins of HBE cells in the miR-4297 mimic + irradiation group were higher than those in the mimic NC + control group and the miR-4297 mimic + control group (all P<0.05), while there was no significant difference compared with those in the mimic NC + irradiation group (all P>0.05). Conclusion MGMT-3′UTR-miRSNP rs7896488 G>A plays a role in LDIR-induced senescence of lung cells with different polymorphic genotypes by affecting miR-4297-targeted regulation of MGMT.

Objective To investigate the effects of fractionated low-dose ionizing radiation (LDIR) on the ferroptosis in human bronchial epithelial (HBE) cells as well as the associated differentially expressed genes (DEGs), biological processes, and signaling pathways. Methods HBE cells were exposed to different single doses of X-ray irradiation (0, 25, 50, 75, and 100 mGy) for 24, 48, and 72 h, respectively. The change in cell viability was detected by MTT assay. Cells were irradiated with 0, 25, 50, and 100 mGy X-rays 5 times, with 48 h between each irradiation and a dose rate of 50 mGy/min. Cells were harvested 24 h after irradiation for the measurement of the expression of ferroptosis-related genes SLC7A11 and GPX4 at the mRNA and protein levels, cellular iron content, and the expression of FTH1 and FTL mRNAs. High-throughput sequencing was used to screen for the DEGs in each dose group, followed by Gene Ontology-Biological Process (GO-BP) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Set Enrichment Analysis (GSEA). Results Compared with the control group, single-dose LDIR significantly increased cell proliferation at 75 mGy after 24 h (P < 0.05), at 50, 75, and 100 mGy after 48 h (P < 0.05), and at 75 and 100 mGy after 72 h (P < 0.05). Compared with the control group, at the end of the fifth fractionated LDIR, SLC7A11 and GPX4 mRNAs decreased at all doses (P < 0.05), SLC7A11 protein decreased at all doses, GPX4 protein decreased at 25 and 100 mGy, iron content increased at all doses, and FTH1 and FTL mRNAs decreased at all doses (P< 0.05). Sequencing analysis identified 248, 30, and 291 DEGs and 10, 2, and 9 ferroptosis-associated genes at the three doses compared to the control. Gene Ontology-Biological Process analysis showed that DEGs were mainly enriched in biological processes such as response to lipids, cell death, and response to unfolded proteins. Kyoto Encyclopedia of Genes and Genomes analysis showed that DEGs were mainly enriched in the JAK-STAT signaling pathway, lipids and atherosclerosis, ferroptosis, protein processing in the endoplasmic reticulum, and FoxO signaling pathway. Gene set enrichment analysis showed that DEGs were mainly enriched in ferroptosis, fatty acid degradation, and glutathione metabolism. Conclusion Fractionated low-dose radiation induced ferroptosis in HBE cells, and DEGs were predominantly enriched in biological processes and signaling pathways related to inflammation, ferroptosis, and endoplasmic reticulum stress.

Objective To investigate the induction of senescence in L02 hepatocytes by low-dose fractionated X-ray radiation and its effects on oxidative stress, oxidative damage, and nuclear factor-κB (NF-κB) pathway protein levels. Methods L02 cells were subjected to fractionated X-ray irradiation at doses of 0.1, 0.2, and 0.5 Gy per fraction for a total of six fractions. Assays were performed 24 hours after the final irradiation. Measurements included SA-β-gal staining, the mRNAs of senescence-related genes p53 and p21 and their encoded proteins, mRNAs of genes encoding senescence-associated secretory phenotype factors (IL-6, IL-8, GM-CSF, MMP-15), reactive oxygen species, oxidative and anti-oxidative markers (malondialdehyde, glutathione, superoxide dismutase), DNA oxidative damage markers (8-OHdG and γ-H2AX), and NF-κB pathway protein levels. Results Compared with the control group, at 24 hours after the end of six irradiations, the number of cells positive in SA-β-gal staining was significantly increased in all dose groups. The mRNA and protein levels of p21 and p53 were significantly elevated in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The mRNA levels of genes encoding IL-6, GM-CSF, and MMP-15 were significantly increased in all dose groups (P < 0.05). The mRNA levels of the gene encoding IL-8 were significantly increased in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The levels of reactive oxygen species, malondialdehyde, and glutathione were significantly increased in all dose groups (P < 0.01). The level of superoxide dismutase was significantly increased in the 0.5 Gy × 6 group (P < 0.01). The levels of 8-OHdG were significantly increased in all dose groups (P < 0.05). In both the 0.2 Gy × 6 and 0.5 Gy × 6 groups, the expression levels of γ-H2AX and p-NF-κB p65 were significantly increased (P < 0.05), and the levels of IκBα were significantly decreased (P < 0.05). Conclusion Low-dose fractionated X-ray radiation can induce senescence and cause alterations in oxidative stress, oxidative damage, and the levels of NF-κB pathway proteins in L02 hepatocytes.

Objective:This report presents the initial outcomes of endoscopic intermuscular dissection (EID), a novel technique introduced by our team for the diagnostic resection of early rectal cancer, focusing on the postoperative status of the vertical margins.Methods:On January 26, 2024, a patient with early rectal cancer (cT1-2N0M0) underwent Endoscopic Intermuscular Dissection. The EID procedure consists of six steps: (1) mucosal incision; (2) submucosal dissection; (3) superficial muscular layer incision; (4) intermuscular dissection; (5) complete tumor removal; (6) wound management.Results:The patient was a 70-year-old male with rectal cancer (cT1-2N0M0). The tumor was located on the left anterior wall of the rectum, approximately 9 cm from the anal margin, and measured 20mm in size. The dissection rate was 2.68 mm2/minute, and the total duration of the surgery was 109 minutes. The patient was successfully discharged on the fifth day after surgery. Pathological examination of the post-endoscopic surgery specimen revealed pT1b, with negative vertical margins. Follow-up after more than one month showed good recovery with no complications such as bleeding, perforation, infection, or stricture occurring. Colonoscopy indicated the presence of a granulation tissue suggestive of inflammation.Conclusion:Endoscopic Intermuscular Dissection for the diagnostic resection of early rectal cancer is potentially safe and may achieve negative vertical margins.

AIM:This study aims to examine the ependymin-related protein 1(EPDR1)expression in various tissues from wild-type C57BL/6 mice and type 2 diabetes(db/db)mice.The impact of EPDR1 on lipid accumulation in al-pha mouse liver 12(AML12)hepatocytes was also investigated.METHODS:Western blot was used to detect EPDR1 protein expression in the heart,liver,spleen,lung,kidney,gastrocnemius,brown adipose and brain tissues of C57BL/6 mice.Western blot and immunohistochemical(IHC)staining were also used to compare EPDR1 protein expression in the liver,gastrocnemius muscle,heart and kidney tissues of db/db and C57BL/6 mice.To develop an AML12 cell lipid deposi-tion model,palmitic acid(PA)+oleic acid(OA)was used,and the cells were transfected with adenovirus overexpressing EPDR1 or treated with exogenous recombinant EPDR1 protein(rEPDR1).ELISA was conducted to determine intracellu-lar triglyceride(TG)content,and oil red O staining was employed to assess the effect of EPDR1 on lipid accumulation in AML12 cells.RESULTS:Western blot and IHC staining results revealed that EPDR1 was widely expressed in various tis-sues of wild-type mice,with the liver exhibiting the highest protein expression level.However,EPDR1 expression was down-regulated in the liver,gastrocnemius muscle,heart and kidney tissues in diabetic db/db mice compared with wild-type mice.Oil red O staining revealed that overexpression of EPDR1 in AML12 liver cells or rEPDR1 treatment led to re-duced lipid accumulation.Furthermore,the TG content significantly decreased compared with the model group(P<0.05).CONCLUSION:EPDR1 is expressed in various tissues of wild-type mice,but showed diminished expression in the liver tissues of diabetic mice.Nevertheless,enhancing the expression of EPDR1 can aid in reducing lipid accumula-tion in hepatocytes.These findings provide an experimental foundation for further exploration of the role of EPDR1 in the development of fatty liver in diabetic liver tissue.

Objective To explore the differentially expressed mRNAs and related biological processes and pathways in fractional low-dose ionizing radiation (LDIR)-induced senescence of normal human bronchial epithelial (HBE) cells by high-throughput mRNA sequencing and bioinformatics techniques. Methods Senescence-associated β-galactosidase staining and senescence-associated secretion phenotype gene mRNA and protein expression levels were measured at 24 and 48 h after irradiating HBE cells 7 times at doses of 0, 50, 100, and 200 mGy, respectively. The differentially expressed genes were screened by high-throughput sequencing for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Results The senescence-positive area of fractional low-dose irradiated HBE cells increased in a dose-dependent manner (P < 0.05). The mRNA levels and protein expression of transforming growth factor-β1(TGF-β1) and matrix metalloproteinase-9(MMP-9) genes were increased in the 100 mGy × 7 and 200 mGy × 7 groups at 24 and 48 h after the end of irradiation compared with the control group. High-throughput sequencing showed that there were 882, 475, and 1205 differentially expressed mRNAs in each dose group compared with the control group. GO analysis showed that the differentially expressed mRNAs in each dose group were mainly enriched in biological processes such as cell cycle regulation, regulation of nitrogen compound metabolic process, regulation of cell division and response to stimulus. KEGG analysis showed that the differentially expressed mRNAs were mainly enriched in the pathways of cell cycle, cell senescence, and ferroptosis. Conclusion Fractional LDIR induced senescence in HBE cells, and differentially expressed mRNA-associated biological processes and pathways in senescent cells are related to cell cycle and cell senescence.

Objective To investigate the mechanism of fractionated low-dose ionizing radiation (LDIR) in the induction of EA.hy926 cell senescence. Methods EA.hy926 cells were irradiated with X-ray at 0, 50, 100, and 200 mGy × 4, respectively, and cultured for 24, 48, and 72 h. Several indicators were measured, including the levels of cellular senescence-associated β-galactosidase (SA-β-gal) staining, mRNA levels of senescence-associated cell cycle protein-dependent kinase inhibitor genes CDKN1A and CDKN2A, reactive oxygen species (ROS), total antioxidant capacity (T-AOC), and phosphorylated H2A histone family member X (γ-H2AX). Results After 4 fractionated LDIR, compared with the control group, the treatment groups showed increased nucleus area, blurred cell edge, and increased SA-β-gal positive area (P < 0.05) at 24, 48 and 72 h. After 4 fractionated LDIR, the mRNA level of CDKN1A increased in the 100 and 200 mGy × 4 groups at 24 and 48 h (P < 0.05), and CDKN2A mRNA level increased in the 100 and 200 mGy × 4 groups at 48 and 72 h (P < 0.05). The fluorescence intensity of ROS increased in treatment groups at 24, 48, and 72 h after 4 fractionated LDIR (P < 0.05). After 4 fractionated LDIR, the T-AOC level increased in the 100 and 200 mGy × 4 groups at 24 h (P < 0.05), and T-AOC level increased in all treatment groups at 48 and 72 h (P < 0.05). After 4 fractionated LDIR, γ-H2AX fluorescence intensity increased in all treatment groups at 24 h (P < 0.05), and the fluorescence intensity increased in the 100 and 200 mGy × 4 groups at 48 and 72 h (P < 0.05). Conclusion Fractionated LDIR can induce cellular senescence in EA.hy926 cells by impacting the cellular oxidation-antioxidation and oxidative damage levels, and the effects were relatively evident at 100 and 200 mGy.

Objective:To investigate the changes in liver injury and oxidative-antioxidant level in mice exposed to X-rays at varying doses.Methods:Fifty-four 8-week-old male C57BL/6J mice were divided into three groups, namely the control, 2 Gy irradiation, and 4 Gy irradiation groups. Then, each of the groups was further divided by days post-irradiation (i.e., 1, 3, and 7 d), and so nine sub-groups ( n = 6). After irradiation was performed as planned, all the mice were dissected and weighed, and their liver indexes were calculated to determine any histopathological changes in the liver. The peripheral blood cell count and the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) were detected. Furthermore, spectrophotometry was also used to determine the superoxide dismutase (SOD) activity, the malondialdehyde (MDA) concentration, and the reduced glutathione (GSH) concentration in liver tissues. Results:Compared to the control group, mice undergoing irradiation exhibited a significant reduction in body weight ( F = 84.03, 27.11, 25.50, P < 0.001), but significantly increased liver indexes ( F = 28.40, 17.75, P <0.001) at 1, 3, and 7 d post-irradiation. Pathological observations of these mice revealed liver injury, which proved related to dose and time course. The counts of leukocytes, neutrophils, and lymphocytes in peripheral blood decreased significantly ( F = 8.42-22.91, P < 0.05), trending downward with an increase in the radiation dose. For mice in the 4 Gy irradiation group, their AST and ALT levels increased significantly at 1 d post-irradiation ( H = 7.24, 7.82, P < 0.05), and their ALP levels rose notably at 1 and 3 d post-irradiation ( F = 11.86, 9.75, P < 0.05). Furthermore, their MDA and SOD levels initially rose and then dropped but their GSH levels exhibited an opposite trend at 1, 3, and 7 d post-irradiation. There was a positive correlation between their MDA levels in the liver and the degree of damage to histopathological lesions at 1, 3, and 7 d post-irradiation ( r = 0.30, P < 0.001). Conclusions:A model for radiation-induced liver injury of mice was preliminarily established in this study. It can be concluded that X-rays at varying doses affect the severity of liver injury, pathological grade, peripheral blood cell count, liver function index, and liver oxidative and antioxidant levels of mice, presenting a certain relationship between dose and time course effects.

Objective:To investigate the safety and efficiency of depilation with intense pulsed light (IPL) in congenital microtia patients during different phase of reconstruction treatment sessions.Methods:The hairy skin was treated with the M22TM system (Lumenis, German) using a filter of 695-1 200 mm. A three pluses mode of the radiant setting with a pulse width of 3.5 ms, a delay of 60 ms, and an energy density of 16-18 mJ/cm 2 was applied in the expanded patients. Depilation efficacy was evaluated as follows: excellent (hair density reduction >75%), good (50%-75%), fair (25%-50%), and poor (<25%). The depilation effect was compared between different phases. And the adverse effect was observed. Results:A total of 131 cases were included. There was no difference of the hair density reduction between patients with different expander volume after same IPL depilation treatments [15 (13-19) vs. 16 (15-19) root/cm 2, Wilcoxon rank analysis]. The hair density reduction in the expansion group was lower than the non-expansion group after two IPL depilation treatments [15 (13-19) vs. 17 (15-21) root/cm 2, P<0.05, Wilcoxon rank analysis]. The depilation efficacy was highly related with the numbers of IPL depilation treatments the patients received [Kendall′ stat b=0.74 (95% CI: 0.71-0.77), P<0.05]. There were 3 cases of folliculitis, 2 cases of blisters occurred in this study, and no expander exposure and cartilage absorption were observed. Conclusions:Hair removal with IPL is a safe and effective photo-epilation method during all stages of ear reconstruction using tissue expander. The volume of the expander does not significantly affect the hair removal efficiency. Depilation in the expansion phase is more efficient than that in the non-expansion phase, and the ideal result of " hair-free" or " less hairy" reconstructed ears can be achieved in 5 treatments, with suboptimal results in 3 treatments.