Oral potentially malignant disorders (OPMDs) are precursors of oral squamous cell carcinoma (OSCC). Deregulated cellular energy metabolism is a critical hallmark of cancer cells. Peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC1α) plays vital role in mitochondrial energy metabolism. However, the molecular mechanism of PGC1α on OPMDs progression is less unclear. Therefore, we investigated the effects of knockdown PGC1α on human dysplastic oral keratinocytes (DOKs) comprehensively, including cell proliferation, cell cycle, apoptosis, xenograft tumor, mitochondrial DNA (mtDNA), mitochondrial electron transport chain complexes (ETC), reactive oxygen species (ROS), oxygen consumption rate (OCR), extracellular acidification rate (ECAR), and glucose uptake. We found that knockdown PGC1α significantly inhibited the proliferation of DOKs in vitro and tumor growth in vivo, induced S-phase arrest, and suppressed PI3K/Akt signaling pathway without affecting cell apoptosis. Mechanistically, downregulated of PGC1α decreased mtDNA, ETC, and OCR, while enhancing ROS, glucose uptake, ECAR, and glycolysis by regulating lactate dehydrogenase A (LDHA). Moreover, SR18292 (an inhibitor of PGC1α) induced oxidative phosphorylation dysfunction of DOKs and declined DOK xenograft tumor progression. Thus, our work suggests that PGC1α plays a crucial role in cell proliferation by reprograming energy metabolism and interfering with energy metabolism, acting as a potential therapeutic target for OPMDs.
Humans ; Carcinoma, Squamous Cell/metabolism* ; Cell Proliferation ; DNA, Mitochondrial ; Energy Metabolism ; Glucose ; Mouth Neoplasms/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism* ; Phosphatidylinositol 3-Kinases ; Reactive Oxygen Species

Humans ; Leigh Disease/therapy* ; Consensus ; Brain ; DNA, Mitochondrial

Humans ; DNA, Mitochondrial ; Cross-Sectional Studies ; East Asian People ; DNA Methylation ; Hypertension/epidemiology* ; China/epidemiology*

Mitochondrial DNA (mtDNA) mutations result in a variety of genetic diseases. As an emerging therapeutic method, mtDNA editing technology recognizes targets more based on the protein and less on the nucleic acid. Although the protein recognition type mtDNA editing technology represented by zinc finger nuclease technology, transcription activator like effector nuclease technology and base editing technology has made some progress, the disadvantages of complex recognition sequence design hinder further popularization. Gene editing based on nucleic acid recognition by the CRISPR system shows superiority due to the simple structure, easy design and modification. However, the lack of effective means to deliver nucleic acids into mitochondria limits application in the field of mtDNA editing. With the advances in the study of endogenous and exogenous import pathways and the deepening understanding of DNA repair mechanisms, growing evidence shows the feasibility of nucleic acid delivery and the broad application prospects of nucleic acid recognition type mtDNA editing technology. Based on the classification of recognition elements, this article summarizes the current principles and development of mitochondrial gene editing technology, and discusses its application prospects.
Genes, Mitochondrial ; Gene Editing ; Mitochondria/genetics* ; DNA, Mitochondrial/genetics* ; Nucleic Acids ; Technology

Humans ; Mitochondrial Diseases/prevention & control* ; DNA, Mitochondrial/genetics*

We identified distinct senescence-related molecular subtypes and critical genes among prostate cancer (PCa) patients undergoing radical prostatectomy (RP) or radical radiotherapy (RT). We conducted all analyses using R software and its suitable packages. Twelve genes, namely, secreted frizzled-related protein 4 (SFRP4), DNA topoisomerase II alpha (TOP2A), pleiotrophin (PTN), family with sequence similarity 107 member A (FAM107A), C-X-C motif chemokine ligand 14 (CXCL14), prostate androgen-regulated mucin-like protein 1 (PARM1), leucine zipper protein 2 (LUZP2), cluster of differentiation 38 (CD38), cartilage oligomeric matrix protein (COMP), vestigial-like family member 3 (VGLL3), apolipoprotein E (APOE), and aldehyde dehydrogenase 2 family member (ALDH2), were eventually used to subtype PCa patients from The Cancer Genome Atlas (TCGA) database and GSE116918, and the molecular subtypes showed good correlations with clinical features. In terms of the tumor immune environment (TME) analysis, compared with cluster 1, cancer-associated fibroblasts (CAFs) scored significantly higher, while endothelial cells scored lower in cluster 2 in TCGA database. There was a statistically significant correlation between both CAFs and endothelial cells with biochemical recurrence (BCR)-free survival for PCa patients undergoing RP. For the GSE116918 database, cluster 2 had significantly lower levels of CAFs and tumor purity and higher levels of stromal, immune, and Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) scores than cluster 1; in addition, patients with high levels of CAFs, stromal scores, immune scores, and ESTIMATE scores and low levels of tumor purity tended to suffer from BCR. Based on the median of differentially expressed checkpoints, high expression of CD96, hepatitis A virus cellular receptor 2 (HAVCR2), and neuropilin 1 (NRP1) in GSE116918 and high expression of CD160 and tumor necrosis factor (ligand) superfamily member 18 (TNFSF18) in TCGA database were associated with a significantly higher risk of BCR than their counterparts. In conclusion, we first constructed distinct molecular subtypes and critical genes for PCa patients undergoing RP or RT from the fresh perspective of senescence.
Male ; Humans ; Endothelial Cells ; Ligands ; Prostatic Neoplasms/pathology* ; Prostate/pathology* ; Prostatectomy ; Aldehyde Dehydrogenase, Mitochondrial ; DNA-Binding Proteins ; Transcription Factors

Humans ; Mitochondrial Diseases/therapy* ; DNA, Mitochondrial/genetics*

OBJECTIVE: The study aimed to estimate the benchmark dose (BMD) of coke oven emissions (COEs) exposure based on mitochondrial damage with the mitochondrial DNA copy number (mtDNAcn) as a biomarker. METHODS: A total of 782 subjects were recruited, including 238 controls and 544 exposed workers. The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction. Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95% confidence lower limit (BMDL). RESULTS: The mtDNAcn of the exposure group was lower than that of the control group (0.60 ± 0.29 vs. 1.03 ± 0.31; P < 0.001). A dose-response relationship was shown between the mtDNAcn damage and COEs. Using the Benchmark Dose Software, the occupational exposure limits (OELs) for COEs exposure in males was 0.00190 mg/m ³. The OELs for COEs exposure using the BBMD were 0.00170 mg/m ³ for the total population, 0.00158 mg/m ³ for males, and 0.00174 mg/m ³ for females. In possible risk obtained from animal studies (PROAST), the OELs of the total population, males, and females were 0.00184, 0.00178, and 0.00192 mg/m ³, respectively. CONCLUSION Based on our conservative estimate, the BMDL of mitochondrial damage caused by COEs is 0.002 mg/m ³. This value will provide a benchmark for determining possible OELs.
Male ; Female ; Animals ; Coke ; Polycyclic Aromatic Hydrocarbons ; DNA Copy Number Variations ; Benchmarking ; Occupational Exposure/analysis* ; DNA, Mitochondrial/genetics* ; DNA Damage

Schizothorax argentatus that only distributes in the Ili River basin in Xinjiang is one of the rare and endangered species of schizothorax in China, thus has high scientific and economic values. In this study, the complete mitochondrial genome sequence of S. argenteus with a length of 16 580 bp was obtained by high-throughput sequencing. The gene compositions and arrangement were similar to those of typical vertebrates. It contained 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a non-coding region (D-loop). The nucleotide compositions were A (30.25%), G (17.28%), C (27.20%), and T (25.27%), respectively, showing obvious AT bias and anti-G bias. Among the tRNA genes, only tRNA-Ser^(GCU) could not form a typical cloverleaf structure due to the lack of dihydrouracil arm. The AT-skew and GC-skew values of the ND6 gene were fluctuating the most, suggesting that the gene may experience different selection and mutation pressures from other genes. The mitochondrial control region of S. argenteus contained three different domains, i.e., termination sequence region (ETAS), central conserved region (CSB-F, CSB-E, CSB-D, and CSB-B), and conserved sequence region (CSB1, CSB2, and CSB3). The conserved sequence fragment TT (AT) nGTG, which was ubiquitous in Cypriniformes, was identified at about 50 bp downstream CSB3. Phylogenetic relationships based on the complete mitochondrial genome sequence of 28 Schizothorax species showed that S. argenteus had differentiated earlier and had a distant relationship with other species, which may be closely related to the geographical location and the hydrological environment where it lives.
Animals ; Genome, Mitochondrial/genetics* ; Phylogeny ; Sequence Analysis, DNA ; Cyprinidae/genetics* ; RNA, Transfer/genetics* ; DNA, Mitochondrial/genetics* ; Genes, Mitochondrial

OBJECTIVE: To explore the correlation of mitochondrial DNA (mtDNA) variants and coronary heart disease (CHD) in a Chinese pedigree and the possible molecular mechanisms. METHODS: A Chinese pedigree featuring matrilineal inheritance of CHD who visited Hangzhou First People's Hospital in May 2022 was selected as the study subject. Clinical data of the proband and her affected relatives was collected. By sequencing the mtDNA of the proband and her pedigree members, candidate variants were identified through comparison with wild type mitochondrial genes. Conservative analysis among various species was conducted, and bioinformatics software was used to predict the impact of variants on the secondary structure of tRNA. Real-time PCR was carried out to determine the copy number of mtDNA, and a transmitochondrial cell line was established for analyzing the mitochondrial functions, including membrane potential and ATP level. RESULTS: This pedigree had contained thirty-two members from four generations. Among ten maternal members, four had CHD, which yielded a penetrance rate of 40%. Sequence analysis of proband and her matrilineal relatives revealed the presence of a novel m.4420A>T variant and a m.10463T>C variant, both of which were highly conserved among various species. Structurally, the m.4420A>T variant had occurred at position 22 in the D-arm of tRNAMet, which disrupted the 13T-22A base-pairing, while the m.10463T>C variant was located at position 67 in the acceptor arm of tRNAArg, a position critical for steady-state level of the tRNA. Functional analysis revealed that patients with the m.4420A>T and m.10463T>C variants exhibited much fewer copy number of mtDNA and lower mitochondrial membrane potential (MMP) and ATP contents (P < 0.05), which were decreased by approximately 50.47%, 39.6% and 47.4%, respectively. CONCLUSION Mitochondrial tRNAMet 4420A>T and tRNAArg 10463T>C variants may underlay the maternally transmitted CHD in this pedigree, which had shown variation in mtDNA homogeneity, age of onset, clinical phenotype and other differences, suggesting that nuclear genes, environmental factors and mitochondrial genetic background have certain influence on the pathogenesis of CHD.
Humans ; Female ; Mutation ; Pedigree ; RNA, Transfer, Met ; East Asian People ; RNA, Transfer, Arg ; DNA, Mitochondrial/genetics* ; Coronary Disease/genetics* ; Adenosine Triphosphate