Currently, the incidence of Parkinson's disease (PD) is on the rise. More and more evidences suggest that mitochondrial dysfunction plays a crucial role in the etiology of PD, and dysfunction of mitochondrial complex I (MCI) is one of the most critical factors leading to mitochondrial dysfunction. On one hand, MCI dysfunction stimulates dopaminergic neurons to produce reactive oxygen species (ROS). On the other hand, MCI dysfunction decreases dopaminergic neuron viability and reduces ATP production. All these outcomes promote the pathological progression of PD. This review summarizes research progress on the role of MCI in the pathogenesis of PD, as well as PD treatment strategies based on MCI.
Parkinson Disease/metabolism* ; Humans ; Electron Transport Complex I/metabolism* ; Mitochondria/physiology* ; Reactive Oxygen Species/metabolism* ; Dopaminergic Neurons/metabolism* ; Animals ; Adenosine Triphosphate/metabolism*

Flavoprotein monooxygenases(FPMOs) and cytochrome P450(CYP450) oxygenases are pivotal monooxygenases in nature, catalyzing crucial redox reactions in diverse biological processes and contributing to the synthesis of highly complex natural products. While CYP450 enzymes have been extensively reported and studied, numerous FPMOs have also been discovered in past research endeavors, yet their classification, catalytic reactions, and catalytic mechanisms remain to be systematically analyzed. This paper comprehensively reviews the latest advancements in FPMOs research, initiating with a classification based on sequence similarities and distinct structural features. It delves into the catalytic characteristics of three subfamilies(FMO, BVMO, and NMO) within Class B FPMOs of plants, which are integral to biosynthetic pathways of natural products. Class B FPMOs encompass two canonical Rossmann fold motifs(FAD-binding GxGxxG and NADPH-binding GxGxxA), along with a central FMO recognition motif FxGxxxHxxxF/Y/W. These enzymes play a key role in regulating various metabolic routes and precisely modulate plant growth and development. Furthermore, the review summarizes the applications of Class B FPMOs of plants, showcasing through concrete examples their potential in synthesizing natural products such as auxins, indigo, and cyanogenic glycosides. These insights will broaden and deepen our understanding of FPMOs, fostering their transition from fundamental research to practical applications. More optimized biosynthetic pathways can be devised by leveraging FPMOs, conducive to the development of novel strategies and tools for agriculture, plant protection, natural product biosynthesis, and synthetic biology.
Biological Products/metabolism* ; Mixed Function Oxygenases/chemistry* ; Flavoproteins/chemistry* ; Plants/metabolism* ; Plant Proteins/chemistry* ; Cytochrome P-450 Enzyme System/genetics*

OBJECTIVES: To investigate the effect of downregulation of medium-chain acyl-coenzyme A dehydrogenase (ACADM) on invasion and migration of estrogen receptor-positive breast cancer cells and the underlying mechanism. METHODS: The Kaplan-Meier Plotter database was used to analyze the ACADM expression levels in breast cancer and normal tissues and their association with patient prognosis. Human breast cancer MCF-7 and T47D cell lines with lentivirus-mediated ACADM knockdown were established, and their in situ tumor formation and metastasis after tail vein injection were evaluated in nude mice. The MCF-7 and T47D cells with ACADM knockdown and their unmodified parental cells were examined with oil-red O staining assay, ROS assay, mitochondrial respiratory chain function assay before and after treatments with ROS scavenger, Elamipretide (a cardiolipin oxidation inhibitor) or SC79 (an AKT activator), and the changes in migration and invasion abilities of the treated cells were analyzed with Transwell invasion assay and Boyden chamber assay. Western blotting was used to detect protein expression levels of related signaling pathways in the treated cells. RESULTS: ACADM overexpression was associated with a significantly shorter overall survival of breast cancer patients. In MCF-7 and T47D cells, ACADM knockdown resulted in downregulation of N calnexin, vimentin, p-P13K and p-AKT proteins, increased levels of free fatty acids and reactive oxygen species, lowered activities of mitochondrial respiratory chain complex III and V, and reduced mitochondrial inner phospholipids. ACADM knockdown significantly decreased the invasive capacity of the cells, which were obviously reversed by treatment with ROS scavenger, Elamipretide, and SC79. CONCLUSIONS Down-regulation of ACADM inhibits migration and invasion ability of estrogen receptor-positive breast cancer cells by lowering lipotoxicity and impairing mitochondrial function through the ROS/PI3K/AKT pathway.
Humans ; Breast Neoplasms/metabolism* ; Female ; Mice, Nude ; Down-Regulation ; Neoplasm Invasiveness ; Animals ; Mice ; Receptors, Estrogen/metabolism* ; MCF-7 Cells ; Cell Movement ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Acyl-CoA Dehydrogenase/genetics* ; Signal Transduction ; Neoplasm Metastasis ; Proto-Oncogene Proteins c-akt/metabolism*

OBJECTIVE: To investigate the intervention of melatonin (MT) in the expression of circadian genes in patients with pulmonary fibrosis and to analyze the mechanism by which it alleviates the progression of pulmonary fibrosis. METHODS: By utilizing the Gene Expression Omnibus (GEO) database, we identified differentially expressed circadian genes between patients with pulmonary fibrosis and controls. We analyzed the correlation between circadian genes and pulmonary function as well as genes related to pulmonary fibrosis. A bleomycin-induced mouse model of pulmonary fibrosis (BLM group) was constructed to observe the expression differences of PER2 and CRY2 by sequencing and immunohistochemical staining in the BLM group and after MT intervention (BLM+MT group). Hematoxylin and eosin (HE) staining and Masson staining were used to observe the effects of MT on fibrosis. We used Western blot to detect the expression of P-smad2/3 in lung epithelial cells induced by transforming growth factor β (TGF-β). Reverse transcription quantitative real-time PCR technology was employed to investigate the rhythmic expression changes of circadian genes in the control group, TGF-β group, and TGF-β+MT group. Finally, luzindole, a MT receptor antagonist, was used to intervene in TGF-β+MT group, and Western blot was used to explore the receptor dependence of MT in alleviating TGF-β-induced epithelial-mesenchymal transition. RESULTS: (1) Analysis of the GEO dataset (GSE) revealed a negative correlation between circadian genes <i>PER2i> and <i>CRY2i> and the expression of <i>TGF-βi>, and a positive correlation with pulmonary function indicators in patients. (2) Transcriptome sequencing analysis of lung tissue in BLM group found that the expression of <i>PER2i> and <i>CRY2i> was significantly reduced compared with the normal group. Histopathological staining results showed that the lung tissue structure of the normal group was intact and clear, with thin alveolar septa; in the BLM group, there was a large increase in collagen fibers and disordered alveolar structure; compared with the BLM group, the BLM+MT group had reduced collagen fiber proliferation and inflammatory cell infiltration; the expression of PER2 and CRY2 in the BLM group was lower than in the normal group, and the expression in the BLM+MT group was increased compared with the BLM group. (3) <i>In vitroi> lung epithelial cell experiments with TGF-β intervention showed that compared with the control group, the expression of P-smad2/3 increased in the TGF-β group, and MT intervention inhibited the inducing effect of TGF-β on P-smad2/3, while intervention with the MT receptor antagonist reversed this phenomenon. The results indicated that MT could inhibit the activation of the TGF-β pathway, and this process was dependent on MT receptors. (4) The 48-hour rhythm experiment in lung epithelial cells showed that the mRNA rhythm of <i>PER2i> and <i>CRY2i> in the TGF-β+MT group was close to 24 hours and showed a trend towards restoring the rhythm of the control group, while the addition of the MT receptor blocker tended to make the rhythm duration and amplitude of both groups approach that of the TGF-β group. CONCLUSION MT, by binding to its receptors, can restore the periodic expression of the circadian genes <i>PER2i> and <i>CRY2i>, thereby inhibiting the activation of the TGF-β classical pathway and suppressing the pathological process of epithelial-mesenchymal transition in pulmonary fibrosis. This finding provides new molecular targets and potential therapeutic strategies for the treatment of pulmonary fibrosis.
Melatonin/pharmacology* ; Animals ; Mice ; Pulmonary Fibrosis/chemically induced* ; Bleomycin ; Humans ; Transforming Growth Factor beta/metabolism* ; Period Circadian Proteins/metabolism* ; Smad3 Protein/genetics* ; Disease Models, Animal ; Lung/pathology* ; Cryptochromes/metabolism* ; Smad2 Protein/genetics* ; Epithelial Cells/metabolism* ; Mice, Inbred C57BL

OBJECTIVE: To explore the clinical and genetic characteristics of four patients with medium-chain acyl-CoA dehydrogenase deficiency (MCADD). METHODS: Four children who had presented at the Children's Hospital Affiliated to Zhengzhou University between August 2019 and August 2021 were selected as the study subjects. Clinical data of the children were collected. The children were subjected to whole exome sequencing (WES). RESULTS: All of the four children were diagnosed with MCADD. Blood amino acid and ester acyl carnitine spectrum test showed that the concentration of octanoyl carnitine (C8) was significantly increased. The main clinical manifestations included poor mental response (3 cases), intermittent diarrhea with abdominal pain (1 case), vomiting (1 case), increased transaminase (3 cases), and metabolic acidosis (2 cases). Five variants were identified by genetic testing, among which c.341A>G (p.Y114C) was unreported previously. Three were missense variants, one was frameshift variant and one was splicing variant. CONCLUSION The clinical heterogeneity of MCADD is obvious, and the severity of the disease may vary. WES can assist with the diagnosis. Delineation of the clinical symptoms and genetic characteristics of the disease can facilitate early diagnosis and treatment of the disease.
Child ; Humans ; Acyl-CoA Dehydrogenase/genetics* ; Carnitine ; Genetic Testing ; Lipid Metabolism, Inborn Errors/genetics* ; Neonatal Screening

OBJECTIVES: To investigate the genotypes and biochemical phenotypes of neonates with abnormal metabolism of butyrylcarnitine (C4). METHODS: One hundred and twenty neonates with increased C4 levels detected by tandem mass spectrometry in the neonatal screening at Children's Hospital, Zhejiang University School of Medicine from January 2018 to June 2023 were included. The initial screening data and recalled data of C4 and C4/C3 were collected and converted into multiples of C4 reference range. Next generation sequencing was performed and the exons with adjacent 50 bp regions of <i>ACAD8i> and <i>ACADSi> genes were captured by liquid phase capture technique. Variant information was obtained by bioinformatic analysis and the pathogenicity were classified according to the American College of Medical Genetics and Genomics criteria. The Wilcoxon rank sum test was used to analyze the differences in C4 levels among neonates with different variation types. RESULTS: In total, 32 variants in <i>ACAD8i> gene were detected, of which 7 variants were reported for the first time; while 41 variants of <i>ACADSi> gene were detected, of which 17 variants have not been previously reported. There were 39 cases with <i>ACAD8i> biallelic variations and 3 cases with <i>ACAD8i> monoallelic variations; 34 cases with <i>ACADSi> biallelic variations and 36 cases with <i>ACADSi> monoallelic variations. Furthermore, 5 cases were detected with both <i>ACAD8i> and <i>ACADSi> gene variations. Inter group comparison showed that the multiples of C4 reference range in initial screening and re-examination of the <i>ACAD8i> biallelic variations and <i>ACADSi> biallelic variations groups were significantly higher than those of the <i>ACADSi> monoallelic variations group (all <i>Pi><0.01), while the multiples in the <i>ACAD8i> biallelic variations group were significantly higher than those in the <i>ACADSi> biallelic variations group (all <i>Pi><0.01). The multiples of C4 reference range in the initial screening greater than 1.5 times were observed in all neonates carrying <i>ACAD8i> or <i>ACADSi> biallelic variations, while only 25% (9/36) in neonates carrying <i>ACADSi> monoallelic variations. CONCLUSIONS <i>ACAD8i> and/or <i>ACADSi> gene variants are the main genetic causes for elevated C4 in newborns in Zhejiang region with high genotypic heterogeneity. The C4 levels of neonates with biallelic variations are significantly higher than those of neonates with monoallelic variations. The cut-off value for C4 level could be modestly elevated, which could reduce the false positive rate in tandem mass spectrometry neonatal screening.
Child ; Humans ; Infant, Newborn ; Acyl-CoA Dehydrogenase/genetics* ; Genotype ; Phenotype ; Carnitine/metabolism* ; Mutation

Objective:b> To investigate the clinicopathological features, immunophenotype, ultrastructure, genetic alterations and prognosis of succinate dehydrogenase-deficient renal cell carcinoma (SDH RCC). Methods:b> A total of 11 SDH RCCs, diagnosed from 2010 to 2019, were selected from the Department of Pathology of Nanjing Jingling Hospital, Nanjing University School of Medicine for clinicopathologic, immunohistochemical (IHC), ultrastructural investigation and follow-up. The molecular features of seven cases were analyzed by the panel-targeted DNA next generation sequencing (NGS). Results:b> There were seven males and four females, with ages ranging from 24 to 62 years (mean 41.4 years, median 41 years). Microscopically, SDH RCC was mainly composed of solid and tubular structures with local cystic change. Four cases showed nested or trabecular structure distributed in a loose hypocellular connective tissue or around scar, similar to oncocytoma. The neoplastic cells demonstrated flocculent eosinophilic cytoplasm with typical intracytoplasmic vacuoles. Immunohistochemically, eight cases were negative for SDHB; three cases showed focal and weak expression, whereas normal renal tubular and vascular endothelial cells demonstrated strong cytoplasmic staining. NGS of DNA targeted-panel detected pathogenic mutations of SDHB gene in seven cases (including three cases with equivocal IHC expression of SDHB), without any mutations in other SDH related genes. There were four cases of SDHB missense mutation, one case of frameshift mutation, one case of splicing mutation, and one case of acquired stop codon mutation. Conclusions:b> SDH RCC is a distinct variant of RCCs with genetic tendency or with hereditary cancer syndrome. NGS is recommended to detect the related gene mutations for a definitive diagnosis. The patients should be closely followed up.
Adult ; Carcinoma, Renal Cell/genetics* ; Endothelial Cells ; Female ; Humans ; Kidney Neoplasms/genetics* ; Male ; Middle Aged ; Prognosis ; Succinate Dehydrogenase/genetics* ; Young Adult

OBJECTIVE: To explore the genetic basis for a child with succinate semialdehyde dehydrogenase deficiency. METHODS: Peripheral blood samples of the proband and his parents were collected and subjected to Sanger sequencing. High-throughput sequencing was used to verify the gene variants. Bioinformatic software was used to analyze the pathogenicity of the variant sites. RESULTS: Sanger sequencing showed that the proband carried a homozygous c.1529C>T (p.S510F) variant of the ALDH5A1 gene, for which his mother was a carrier. The same variant was not detected in his father. However, high-throughput sequencing revealed that the child and his father both had a deletion of ALDH5A1 gene fragment (chr6: 24 403 265-24 566 986). CONCLUSION The c.1529C>T variant of the ALDH5A1 gene and deletion of ALDH5A1 gene fragment probably underlay the disease in the child. High-throughput sequencing can detect site variation as well as deletion of gene fragment, which has enabled genetic diagnosis and counseling for the family.
Amino Acid Metabolism, Inborn Errors/genetics* ; Child ; Developmental Disabilities ; Humans ; Infant ; Mutation ; Succinate-Semialdehyde Dehydrogenase/genetics*

OBJECTIVE: To analyze the clinical features and genetic variants in four neonates with very long chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency. METHODS: Neonates with a tetradecenoylcarnitine (C14:1) concentration at above 0.4 μmol/L in newborn screening were recalled for re-testing. Four neonates were diagnosed with VLCAD deficiency by MS-MS and genetic testing, and their clinical features and genotypes were analyzed. RESULTS: All cases had elevated blood C14:1, and the values of first recalls were all lower than the initial test. In 2 cases, the C14:1 had dropped to the normal range. 1 case has remained at above 1 μmol/L after the reduction, and the remainder one case was slightly decreased. In total eight variants of the ADACVL genes were detected among the four neonates, which included 5 missense variants and 3 novel variants (p.Met344Val, p.Ala416Val, c.1077+6T>A). No neonate showed salient clinical manifestations. CONCLUSION Above findings have enriched the spectrum of ADACVL gene mutations and provided a valuable reference for the screening and diagnosis of VLCAD deficiency.
Acyl-CoA Dehydrogenase/genetics* ; Acyl-CoA Dehydrogenase, Long-Chain ; Congenital Bone Marrow Failure Syndromes ; Genetic Testing ; Humans ; Infant, Newborn ; Lipid Metabolism, Inborn Errors ; Mitochondrial Diseases ; Muscular Diseases ; Tandem Mass Spectrometry

Bone regeneration remains a great clinical challenge. Low intensity near-infrared (NIR) light showed strong potential to promote tissue regeneration, offering a promising strategy for bone defect regeneration. However, the effect and underlying mechanism of NIR on bone regeneration remain unclear. We demonstrated that bone regeneration in the rat skull defect model was significantly accelerated with low-intensity NIR stimulation. In vitro studies showed that NIR stimulation could promote the osteoblast differentiation in bone mesenchymal stem cells (BMSCs) and MC3T3-E1 cells, which was associated with increased ubiquitination of the core circadian clock protein Cryptochrome 1 (CRY1) in the nucleus. We found that the reduction of CRY1 induced by NIR light activated the bone morphogenetic protein (BMP) signaling pathways, promoting SMAD1/5/9 phosphorylation and increasing the expression levels of Runx2 and Osterix. NIR light treatment may act through sodium voltage-gated channel Scn4a, which may be a potential responder of NIR light to accelerate bone regeneration. Together, these findings suggest that low-intensity NIR light may promote in situ bone regeneration in a CRY1-dependent manner, providing a novel, efficient and non-invasive strategy to promote bone regeneration for clinical bone defects.
Animals ; Rats ; Bone Morphogenetic Protein 2/metabolism* ; Bone Regeneration ; Cell Differentiation ; Circadian Clocks ; Cryptochromes/metabolism* ; Osteoblasts/metabolism* ; Osteogenesis ; Transcription Factors/metabolism*