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1.
J Clin Invest ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743490

RESUMO

Impairment of oligodendrocytes and myelin contributes to neurological disorders including multiple sclerosis (MS), stroke and Alzheimer's disease. Regeneration of myelin (remyelination) decreases the vulnerability of demyelinated axons, but this repair process commonly fails with disease progression. A contributor to inefficient remyelination is the altered extracellular matrix (ECM) in lesions that remains to be better defined. We have identified fibulin-2 (FBLN2) as a highly upregulated ECM component in lesions of MS and stroke, and in proteome databases of Alzheimer's disease and traumatic brain injury. Focusing on MS, the inhibitory role of FBLN2 was suggested in the experimental autoimmune encephalomyelitis (EAE) model in which genetic FBLN2 deficiency improved behavioral recovery by promoting the maturation of oligodendrocytes and enhancing remyelination. Mechanistically, when oligodendrocyte progenitors were cultured in differentiation media, FBLN2 impeded their maturation into oligodendrocytes by engaging the Notch pathway, leading to cell death. Adeno-associated virus-deletion of FBLN2 in astrocytes improved oligodendrocyte numbers and functional recovery in EAE and generated new myelin profiles after lysolecithin-induced demyelination. Collectively, our findings implicate FBLN2 as a hitherto unrecognized injury-elevated ECM, and a therapeutic target, that impairs oligodendrocyte maturation and myelin repair.

2.
Ann Hematol ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38761185

RESUMO

Acquired pure red cell aplasia (PRCA) is anemia associated with the absence of erythroblasts and is characterized by persistent and easy recurrence. However, the underlying mechanisms of acquired PRCA remain obscure, and the role of gene mutations in the pathogenesis of acquired PRCA is not fully characterized. In the present study, we detected thirty newly diagnosed patients with acquired PRCA using whole exome sequencing, and a potential role for STK10 in acquired PRCA was uncovered. The mRNA levels of STK10 in three patients with STK10 mutations were decreased. These three patients had a poor response to immunosuppressive therapy and two died in the follow-up period. Here we report that knockdown of STK10 inhibits erythroid differentiation and promotes apoptosis of K562 cells. We show that knockdown of STK10 resulted in inhibition of ribosome biogenesis and reduced ribosome levels in K562 cells. We also show that the p53 signaling pathway is activated by knockdown of STK10. Our results imply that ribosome biogenesis downregulation together with pathological p53 activation prevents normal erythropoiesis. Our study uncovers a new pathophysiological mechanism leading to acquired PRCA driven by STK10 mutations.

3.
Drugs R D ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644462

RESUMO

BACKGROUND AND OBJECTIVE: Ornidazole, the third generation of nitroimidazole derivatives after metronidazole and tinidazole, it exerts both bactericidal and antiprotozoal effects. The purpose of this study was to evaluate the pharmacokinetic and bioequivalence of two ornidazole tablets manufactured by two different manufacturers based on their pharmacokinetic parameters. PATIENTS AND METHODS: Fasted and fed healthy Chinese volunteers participated in a randomized sequence, single-dose, open-label, two-period crossover trial. There were 24 participants in both the fed study and the fasted study. Following a 7-day washout period before receiving the alternative formulation, eligible research participants were randomly assigned (1:1) to receive a single dosage of either the reference formulation or the test formulation. Following tablet administration, plasma samples were obtained over 72 h and analyzed using liquid chromatography tandem mass spectrometry (LC-MS/MS) to evaluate ornidazole contents. maximum plasma concentration (Cmax), time to Cmax (Tmax), the area under the curve (AUC) from t = 0 to infinity (AUC0-∞), AUC from t = 0 to the last quantifiable concentration (AUC0-t), half-life (t1/2), and terminal elimination rate constant (z) were evaluated as pharmacokinetic (PK) parameters. The safety evaluation involved adverse events (AEs) incidence and alterations in laboratory tests (hepatic function, blood biochemistry, hematology, and urinalysis) or vital signs (temperature, pulse, and blood pressure). RESULTS: For the bioequivalence assessment in the fast trial, the prime PK parameters comparison between the reference and test formulation revealed that the GMR (90% CI) values for AUC0-t, Cmax, and AUC0-∞ were 100.97% (99.12-102.85%), 99.88% (90.63-110.08%), and 101.12% (99.17-103.11%), respectively. For the bioequivalence assessment in the fed trial, the key PK parameters comparison between the reference and test formulations revealed that the GMR (90% CI) values for AUC0-t, Cmax, and AUC0-∞ were 103.00% (100.94-105.11%), 101.90% (99.63-104.22%), and 102.99% (100.87-105.16%), respectively. The geometric mean ratios (GMRs) for the primary pharmacokinetic parameters (Cmax, AUC0-72, and AUC0-∞) between the two formulations and the corresponding 90% confidence intervals (CIs) were all within the range of 80.00-125.00% for both the fasting and fed states. Both treatments have comparable safety profiles. CONCLUSION: The bioequivalence and tolerability of ornidazole tablet reference and test formulations were evaluated among healthy Chinese participants under both fasting and fed conditions. The results indicated that both formulations were bioequivalent and generally well tolerated; besides, the interaction between food and drug may affect drug pharmacokinetics. TRIAL REGISTRATION: CTR20212873, registered on 15 November 2021; ChiCTR2300069098, registered on 7 March 2023.

4.
Transl Cancer Res ; 13(3): 1367-1381, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38617526

RESUMO

Background: Head and neck squamous cell carcinoma (HNSCC) is the most common type and accounts for 90% of all head and neck cancer cases. Despite advances in early diagnosis and treatment strategies-chemotherapy, surgical resection, and radiotherapy-5-year survival remains grim. For patients with early-stage HNSCC, accurately predicting clinical outcomes is challenging. Considering the pivotal role of the immune system in HNSCC, we developed a reliable immune-related gene signature (IRGS) and explored its predictive accuracy in patients with early-stage HNSCC. Methods: We examined immune gene expression profiles and clinical information from 230 early-stage HNSCC specimens, including 100 cases from The Cancer Genome Atlas (TCGA), 49 cases from the Gene Expression Omnibus (GEO; GSE65858), and 81 cases from an independent clinical cohort. The prognostic signature was constructed using Kaplan-Meier analysis and the least absolute shrinkage and selection operator (LASSO) Cox algorithm. We also explored the IRGS-related biological pathways and immune landscape using bioinformatics analysis. Results: A nine-immune-gene signature was generated to significantly stratify patients into high and low-risk groups. High risk patients exhibited shorter survival time [hazard ratio (HR) =13.795, 95% confidence interval (CI): 3.275-58.109, P<0.001]. The signature demonstrated robust prognostic ability in the training and validation sets and could independently predict overall survival (OS) and relapse-free survival (RFS). Subsequently, the receiver operating characteristic (ROC) curve and C-index confirmed the signature's predictive accuracy compared to clinical parameters. Additionally, cases classified as low risk showed more immune cell infiltration than high-risk cases. Conclusions: Our novel IRGS is a reliable and robust classifier for accurate patient stratification and prognostic evaluation. Future studies will attempt to affirm the signature's clinical application to early-stage HNSCC.

5.
Ecotoxicol Environ Saf ; 274: 116176, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479309

RESUMO

Ambient air pollution is a major global health concern. Yet, no study has thoroughly assessed its link to respiratory mortality. Our research evaluated the combined and individual effects of air pollutants on respiratory mortality risks based on the UK Biobank. A total of 366,478 participants were studied. A Cox proportional hazards model was used to estimate the respiratory mortality risk from combined long-term exposure to five pollutants, summarized as a weighted air pollution score. During a median of 13.6 years of follow-up, 6113 deaths due to respiratory diseases were recorded. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) of respiratory diseases were 2.64 (2.05-3.39), 1.62 (1.23-2.12), 2.06 (1.73-2.45), 1.20 (1.16-1.25), and 1.07 (1.05-1.08) per 10 µg/m3 increase in PM2.5, PM2.5-10, PM10, NO2, and NOx, respectively. The air pollution score showed a dose-response association with an elevated respiratory mortality risk. The highest versus lowest quartile air pollution score was linked to a 44% increase in respiratory mortality risk (HR 1.44, 95% CI: 1.33-1.57), with consistent findings in subgroup and sensitivity analyses. Long-term individual and joint air-pollutant exposure showed a dose-response association with an increased respiratory mortality risk, highlighting the importance of a comprehensive air-pollutant assessment to protect public health.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doenças Respiratórias , Humanos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Material Particulado/análise , Estudos Prospectivos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Doenças Respiratórias/epidemiologia , Dióxido de Nitrogênio
6.
Toxicon ; 242: 107703, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38522586

RESUMO

Benthic freshwater cyanobacteria have the potential to produce toxins. Compared with more extensively studied plankton species, little is known about the impact of harmful benthic cyanobacteria on aquatic organisms. As demersal fish are usually in direct contact with benthic cyanobacteria, it is important to understand their interactive effects. This study investigated the physio-chemical responses of two demersal fish (Xenocypris davidi and Crucian carp) after exposure to benthic Oscillatoria (producing cylindrospermopsin, 2 × 106 cells/mL) for 7 days. Interestingly, benthic Oscillatoria had less adverse effects on X. davidi than C. carp. The two demersal fish effectively ingested Oscillatoria, but Oscillatoria cell sheathes could not be fully digested in C. carp intestines and led to growth inhibition. Oscillatoria consumption induced oxidative stress and triggered alterations in detoxification enzyme activities in the X. davidi liver. Superoxide dismutase (SOD) and glutathione reductase (GR) activities significantly increased in the C. carp liver, but catalase (CAT) and detoxification enzymes glutathione S-transferase (GST) and glutathione (GSH) activities were insignificantly changed. This suggested that C. carp may have a relatively weak detoxification capacity for toxic Oscillatoria. Oscillatoria ingestion led to more pronounced liver pathological changes in C. carp, including swelling, deformation, and loss of cytoskeleton structure. Simultaneously, fish consumption of Oscillatoria increased extracellular cylindrospermopsin concentration. These results provide valuable insights into the ecological risks associated with benthic cyanobacteria in aquatic ecosystems.


Assuntos
Toxinas Bacterianas , Carpas , Toxinas de Cianobactérias , Fígado , Estresse Oxidativo , Animais , Fígado/patologia , Toxinas Bacterianas/toxicidade , Cianobactérias , Antioxidantes/metabolismo , Alcaloides , Oscillatoria , Uracila/análogos & derivados , Uracila/toxicidade , Superóxido Dismutase/metabolismo , Toxinas Marinhas/toxicidade
7.
J Nutr ; 154(4): 1262-1270, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367806

RESUMO

BACKGROUND: The relationship between whole grain intake and chronic kidney disease (CKD) remains uncertain. OBJECTIVE: This study aimed to evaluate the association between whole grain intake and risk of CKD in Chinese adults. METHODS: The present cross-sectional study used data from the China Health and Nutrition Survey conducted in 2009. Whole grain intake was measured using 3 consecutive 24-h dietary recalls and a household food inventory. A multivariable logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of CKD. In addition, a restricted cubic spline was used to investigate the dose‒response relationship between whole grain and risk of CKD. RESULTS: A total of 6747 participants were included, 728 of whom had CKD. Compared with those in the lowest whole grain intake group, those in the higher grain intake group had an inverse association with risk of CKD (Q2: adjusted OR 0.70, 95% CI: 0.54, 0.89; Q3: adjusted OR 0.54, 95% CI: 0.42, 0.69; and Q4: adjusted OR 0.29, 95% CI: 0.21, 0.41). The association between whole grain intake and CKD seems to be stronger for individuals who were male (P for interaction = 0.008) or smokers (P for interaction = 0.013). In addition, the restricted cubic spline suggested an obvious L-shaped correlation. CONCLUSIONS: Increased whole grain intake was associated with a decreased risk of CKD in Chinese adults.


Assuntos
Insuficiência Renal Crônica , Grãos Integrais , Adulto , Humanos , Masculino , Feminino , Estudos Transversais , Insuficiência Renal Crônica/epidemiologia , Dieta , Inquéritos Nutricionais
9.
Clin Pharmacol Drug Dev ; 13(4): 360-366, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38226890

RESUMO

To determine the pharmacokinetics (PK), safety, and bioequivalence profiles of 0.5-g calcium dobesilate capsules in both fasting and fed states for the test drug and reference drug. A randomized-sequence, single-dose, open-label, 2-period crossover study was conducted in fasted and fed healthy Chinese volunteers (Chinese Clinical Trials Registry identifier: CTR202000268-01). The fasting and fed studies, both involving 24 subjects, were conducted. A single dosage of either the reference or the test preparation was given to each eligible subject in a 1:1 ratio, followed by a 7-day rest interval before the administration of the alternative formulation. After taking the capsules, plasma samples were taken for 48 hours, and using liquid chromatography-tandem mass spectrometry, the calcium dobesilate level was determined. The PK parameters evaluated in the study included the maximum serum concentration (Cmax), area under the plasma concentration-time curve (AUC) from time 0 to the last quantifiable concentration, AUC from time 0 to infinity, half-life, time to Cmax, and terminal elimination rate constant. In addition, the safety evaluation encompassed monitoring fluctuations in vitals (temperature, pulse, and blood pressure) and laboratory tests (urinalysis, hepatic function, blood biochemistry, and hematology), as well as recording the emergence of adverse events (AEs). The geometric mean ratio (GMR) of the test/reference medications was used to assess bioequivalence by determining if the 90% confidence intervals of the GMR fell within the predefined range of 80%-125%. AEs were assessed as safety end points. The study included 48 healthy Chinese volunteers (with n = 24 each for the fasting and the fed conditions), and no subjects dropped out for any reason. The differences in the PK metrics for the test and reference drugs for both conditions were insignificant (P > .05). For bioequivalence, irrespective of whether the food was consumed or not, the range of the 90% confidence intervals of the GMR for Cmax, AUC from time 0 to the last quantifiable concentration, and AUC from time 0 to infinity was between 80% and 125%. In the experiment, no serious AEs were recorded. Our findings revealed that the calcium dobesilate capsules used as the reference and the test drugs were both bioequivalent. Irrespective of whether the healthy Chinese volunteers consumed food or not, the PK and safety profiles were comparable.


Assuntos
Dobesilato de Cálcio , Humanos , Área Sob a Curva , Disponibilidade Biológica , China , Estudos Cross-Over , Jejum , Equivalência Terapêutica , Voluntários , População do Leste Asiático
10.
Electrophoresis ; 45(9-10): 877-884, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38196015

RESUMO

Macrohaplotype combines multiple types of phased DNA variants, increasing forensic discrimination power. High-quality long-sequencing reads, for example, PacBio HiFi reads, provide data to detect macrohaplotypes in multiploidy and DNA mixtures. However, the bioinformatics tools for detecting macrohaplotypes are lacking. In this study, we developed a bioinformatics software, MacroHapCaller, in which targeted loci (i.e., short TRs [STRs], single nucleotide polymorphisms, and insertion and deletions) are genotyped and combined with novel algorithms to call macrohaplotypes from long reads. MacroHapCaller uses physical phasing (i.e., read-backed phasing) to identify macrohaplotypes, and thus it can detect multi-allelic macrohaplotypes for a given sample. MacroHapCaller was validated with data generated from our designed targeted PacBio HiFi sequencing pipeline, which sequenced ∼8-kb amplicon regions harboring 20 core forensic STR loci in human benchmark samples HG002 and HG003. MacroHapCaller also was validated in whole-genome long-read sequencing data. Robust and accurate genotyping and phased macrohaplotypes were obtained with MacroHapCaller compared with the known ground truth. MacroHapCaller achieved a higher or consistent genotyping accuracy and faster speed than existing tools HipSTR and DeepVar. MacroHapCaller enables efficient macrohaplotype analysis from high-throughput sequencing data and supports applications using discriminating macrohaplotypes.


Assuntos
Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Polimorfismo de Nucleotídeo Único , Poliploidia , Análise de Sequência de DNA , Software , Humanos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Algoritmos , Biologia Computacional/métodos , DNA/genética , DNA/análise , Repetições de Microssatélites/genética , Genética Forense/métodos , Técnicas de Genotipagem/métodos
11.
Ann Hematol ; 103(2): 397-404, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38082101

RESUMO

To understand the current situation of hepatitis-related aplastic anemia (HAAA) in children, we analyzed the patients with HAAA admitted to our hospital in the past 5 years to understand the disease characteristics and prognosis. The clinical data of patients with HAAA admitted to our hospital from February 2017 to May 2022 were retrospectively analyzed. A total of 81 patients with HAAA, 56 males and 25 females. The median onset age was 5.9 years. The median time from hepatitis to occurrence of hemocytopenia was 30 days, and the median follow-up time was 2.77 years. There were 23 cases (28.5%) of severe aplastic anemia (SAA), 50 cases of very severe aplastic anemia (VSAA), and 8 cases of non-severe aplastic anemia (NSAA). At the beginning of the disease, cytotoxic T lymphocyte (CTL) was higher than normal in 60% of patients, and the median CD4/CD8 ratio was 0.2. As of follow-up, 72 children survived, 4 were lost, and 5 died. Thirty-four cases were treated with immunosuppressive therapy (IST), with a median follow-up time of 0.97 years. The total reaction rate was 73.5% (25/34), the complete reaction rate was 67.6% (23/34), and the nonreaction rate was 26.5% (9/34). Multivariate analysis suggested that co-infection was an independent risk factor affecting the efficacy of IST at 6 months, with an OR value of 16.76, 95% CI (1.23, 227.95), P=0.034. No independent influencing factors were found at the end of follow-up. The proportion of CTL cells in peripheral blood of children with HAAA is relatively increased, and IST is effective in 73.5% of children. Co-infection may prolongs the time to response to IST.


Assuntos
Anemia Aplástica , Coinfecção , Hepatite A , Hepatite , Criança , Masculino , Feminino , Humanos , Pré-Escolar , Anemia Aplástica/terapia , Anemia Aplástica/tratamento farmacológico , Estudos Retrospectivos , Hepatite/complicações , Hepatite/epidemiologia , Resultado do Tratamento , Imunossupressores/uso terapêutico
12.
Neurosci Bull ; 40(2): 255-267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37391607

RESUMO

Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation. Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases, including cochlear inflammation. The distribution, number, and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions, including noise exposure, ototoxicity, and age-related degeneration. However, the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear. Here, we summarize the major factors and mitochondrial signaling pathways (e.g., metabolism, mitochondrial reactive oxygen species, mitochondrial DNA, and the inflammasome) that influence macrophage activation in the innate immune response. In particular, we focus on the properties of cochlear macrophages, activated signaling pathways, and the secretion of inflammatory cytokines after acoustic injury. We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.


Assuntos
Imunidade Inata , Macrófagos , Humanos , Cóclea/metabolismo , Cóclea/patologia , Inflamação/metabolismo , Mitocôndrias
13.
Reproduction ; 167(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37903183

RESUMO

In brief: Oocyte vitrification leads to DNA hypomethylation, which results in defect in early embryo development. This study reveals that oocyte vitrification impairs the DNA methylation pattern by influencing protein O-GlcNAcylation. Abstract: Oocyte vitrification leads to decreased DNA methylation levels, which impairs the quality and the developmental potential of oocytes. However, the underlying molecular mechanism still need to be further revealed. In this study, mouse metaphase II (M II) oocytes were frozen by vitrification technology, while fresh oocytes were used as the control group. The effect of oocyte vitrification on protein O-GlcNAcylation and its impact on the developmental potential of oocytes were elucidated. We found that the protein O-GlcNAcylation levels were significantly increased in vitrified oocytes. Increase of protein O-GlcNAcylation levels in control oocytes by PUGNAc (an O-GlcNAcase inhibitor) decreases blastocyst rate after parthenogenetic activation (20.82% in PUGNAc-treated group; 53.82% in control group, P < 0.05). We also discovered that DNA methylation was disrupted in two-cell embryos derived from vitrified oocytes, resulting in decreased 5mC and increased 5hmC, showing similar phenotypes to that derived from PUGNAc-treated oocytes. In vitrified and PUGNAc-treated oocytes, O-GlcNAcylated TET3 was significantly increased. Notably, by inhibiting protein O-GlcNAcylation in vitrified oocytes using OSMI1 (an O-GlcNAc transferase inhibitor) we restored the DNA methylation in two-cell embryos and ameliorated the developmental defects in early embryo. Thus, elevated protein O-GlcNAcylation in vitrified oocytes is an essential contributor to their declining embryonic developmental potential. Modulation of protein O-GlcNAcylation improves the developmental potential of vitrified oocytes.


Assuntos
Criopreservação , Vitrificação , Animais , Camundongos , Criopreservação/métodos , Metáfase , Oócitos/metabolismo
14.
Sci Total Environ ; 912: 169302, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38104816

RESUMO

The risks of planktonic cyanobacteria blooms have been the focus of much scientific research, but studies on the ecotoxicological effects of benthic cyanobacteria are lagging. The impacts of cyanobacteria cells on fish populations might be more complex in contrast to purified cyanotoxins or cyanobacteria extracts. This study systematically compared the chronic effects of benthic Oscillatoria sp. (producing cylindrospermopsins) and planktonic Microcystis aeruginosa (producing microcystins) on the growth and reproduction of zebrafish through life-cycle exposure (5- 90 days post fertilization). The results showed that both Oscillatoria sp. and M. aeruginosa exposure caused growth inhibition and fecundity reduction in F0 generation by disrupting sex hormone levels, delayed ovarian and sperm development, and induced pathological lesions in zebrafish gonads. Furthermore, exposure to Oscillatoria sp. or M. aeruginosa in adult zebrafish increased mortality and teratogenicity in F1 embryos (without exposure), indicating a parental transmission effect of developmental toxicity. The difference was that M. aeruginosa exposure led to significant alterations in pathways, such as tissue development, redox processes, and steroid hormone synthesis. In contrast, Oscillatoria sp. exposure primarily disrupted the PPAR signaling pathway, cell adhesion molecules, and lipid transport pathways. Interestingly, the differentially expressed genes revealed that male fish were more sensitive to harmful cyanobacteria than females, whether exposed to Oscillatoria sp. or M. aeruginosa. These findings contribute to a better mechanistic understanding of the chronic toxic effects of distinct types of harmful cyanobacteria, suggesting that the ecological risk of benthic cyanobacteria requires further attention.


Assuntos
Cianobactérias , Microcystis , Oscillatoria , Animais , Feminino , Masculino , Microcystis/fisiologia , Peixe-Zebra/metabolismo , Sêmen , Microcistinas/metabolismo , Reprodução , Estágios do Ciclo de Vida
15.
FASEB J ; 38(1): e23332, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095232

RESUMO

Severe hypoxia induced by vascular compromise (ovarian torsion, surgery), obliteration of vessels (aging, chemotherapy, particularly platinum drugs) can cause massive follicle atresia. On the other hand, hypoxia increases the occurrence of DNA double-strand breaks (DSBs) and triggers cellular damage repair mechanisms; however, if the damage is not promptly repaired, it can also induce the apoptosis program. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone that plays essential roles in stimulating mammalian follicular development. Here, we report a novel role for IGF-I in protecting hypoxic GCs from apoptosis by promoting DNA repair through the homologous recombination (HR) process. Indeed, the hypoxic environment within follicles significantly inhibited the efficiency of HR-directed DNA repair. The presence of IGF-I-induced HR pathway to alleviate hypoxia-induced DNA damage and apoptosis primarily through upregulating the expression of the RAD51 recombinase. Importantly, we identified a new transcriptional regulator of RAD51, namely E2F8, which mediates the protective effects of IGF-I on hypoxic GCs by facilitating the transcriptional activation of RAD51. Furthermore, we demonstrated that the PI3K/AKT pathway is crucial for IGF-I-induced E2F8 expression, resulting in increased RAD51 expression and enhanced HR activity, which mitigates hypoxia-induced DNA damage and thereby protects against GCs apoptosis. Together, these findings define a novel mechanism of IGF-I-mediated GCs protection by activating the HR repair through the PI3K/AKT/E2F8/RAD51 pathway under hypoxia.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Reparo de DNA por Recombinação , Feminino , Animais , Suínos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Insulin-Like I/genética , Reparo do DNA , Recombinação Homóloga , Rad51 Recombinase/genética , Hipóxia , Células da Granulosa/metabolismo , Apoptose , Mamíferos/metabolismo
16.
Front Mol Neurosci ; 16: 1251432, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025264

RESUMO

Background: Intracerebral hemorrhage (ICH) is the predominant type of hemorrhagic stroke with high mortality and disability. In other neurological conditions, the deposition of extracellular matrix (ECM) molecules is a prominent obstacle for regenerative processes and an enhancer of neuroinflammation. Whether ECM molecules alter in composition after ICH, and which ECM members may inhibit repair, remain largely unknown in hemorrhagic stroke. Methods: The collagenase-induced ICH mouse model and an autopsied human ICH specimen were investigated for expression of ECM members by immunofluorescence microscopy. Confocal image z-stacks were analyzed with Imaris 3D to assess the association of immune cells and ECM molecules. Sections from a mouse model of multiple sclerosis were used as disease and staining controls. Tissue culture was employed to examine the roles of ECM members on oligodendrocyte precursor cells (OPCs). Results: Among the lectican chondroitin sulfate proteoglycan (CSPG) members, neurocan but not aggrecan, versican-V1 and versican-V2 was prominently expressed in perihematomal tissue and lesion core compared to the contralateral area in murine ICH. Fibrinogen, fibronectin and heparan sulfate proteoglycan (HSPG) were also elevated after murine ICH while thrombospondin and tenascin-C was not. Confocal microscopy with Imaris 3D rendering co-localized neurocan, fibrinogen, fibronectin and HSPG molecules to Iba1+ microglia/macrophages or GFAP+ astrocytes. Marked differentiation from the multiple sclerosis model was observed, the latter with high versican-V1 and negligible neurocan. In culture, purified neurocan inhibited adhesion and process outgrowth of OPCs, which are early steps in myelination in vivo. The prominent expression of neurocan in murine ICH was corroborated in human ICH sections. Conclusion: ICH caused distinct alterations in ECM molecules. Among CSPG members, neurocan was selectively upregulated in both murine and human ICH. In tissue culture, neurocan impeded the properties of oligodendrocyte lineage cells. Alterations to the ECM in ICH may adversely affect reparative outcomes after stroke.

17.
BMC Med Educ ; 23(1): 890, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38012762

RESUMO

BACKGROUND: Public health workers are a crucial part of the health workforce, particularly during the coronavirus disease (COVID-19) pandemic. They play an important role in achieving universal health coverage and sustainable development goals. Human resources in public health in China are in short supply, their distribution is unequal, and their turnover rate is high. A discrete choice experiment (DCE) was applied to investigate preventive medicine students' preferred job choice criteria and trends in trade-offs by calculating the marginal rate of substitution between these criteria. This study identified the properties of jobs primarily selected by preventive medicine students and estimated the monetary value of each attribute. METHODS: Based on discussions and in-depth interviews with preventive medicine students and a literature review, we developed a DCE that assessed how students' stated preferences for a certain choice were influenced by several job attributes, including location, salary, bianzhi, career development opportunities, working environment, and workload. We applied this DCE to preventive medicine students in Shandong Province, China, using a brief, structured questionnaire. Conditional logit models were used to estimate the utility of each job's attributes. Willingness to pay (WTP) was estimated as the ratio of the value of the coefficient of interest to the negative value of the cost attribute. RESULTS: A total of 307 respondents completed the questionnaire, and 261 passed the internal consistency test. All the attributes were statistically significant. Career development opportunities and work locations were the most important factors for the respondents. Preference heterogeneity existed among respondents, e.g., 3-year medical education college students placed a higher value on jobs with bianzhi compared to 5-year medical education college students. Furthermore, rural students' WTP for a job located in the county or city is much lower than that of urban students. CONCLUSIONS: The heterogeneity of attributes indicates the complexity of job preferences. Monetary and nonmonetary job characteristics significantly influenced the job preferences of preventive medicine students in China. A more effective policy intervention to attract graduates to work in rural areas should consider both job incentives and the backgrounds of preventive medicine graduates.


Assuntos
COVID-19 , Escolha da Profissão , Humanos , Pandemias/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudantes , Inquéritos e Questionários , China/epidemiologia , Comportamento de Escolha
18.
J Agric Food Chem ; 71(49): 19705-19716, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38029323

RESUMO

Our previous study with artificial intelligence (AI)-assisted screening found that diosmin, a natural flavonoid extracted from citrus, may affect myoblast proliferation and differentiation. At present, few studies have been conducted regarding the biological function of diosmin in muscle cells. Here, using molecular biological techniques, we found that diosmin elevated the proliferation ability of C2C12 myoblasts via activating the Akt/FOXO1 pathway to promote FOXO1 nuclear export, thus repressing p27 protein expression, increasing CDK2, CDK4, and cyclin D1 and cyclin E1 protein expression and accelerating cell cycle transformation, which contributed to myogenesis. Moreover, diosmin suppressed differentiation of C2C12 myoblasts by delaying the terminal exit of the cell cycle in early differentiated myoblasts and inhibiting autophagic flux in mature myotubes. Furthermore, diosmin promoted myogenesis by activating the Akt/FOXO1 pathway to facilitate myoblast proliferation, which had a positive biological effect on the repair of muscle injury. This study revealed the effect and mechanism of diosmin on skeletal muscle cells and simultaneously provided a new candidate drug for the treatment of myopathy.


Assuntos
Diosmina , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diosmina/metabolismo , Diosmina/farmacologia , Inteligência Artificial , Proliferação de Células , Mioblastos , Diferenciação Celular , Desenvolvimento Muscular
19.
Front Pharmacol ; 14: 1247550, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841923

RESUMO

Intracerebral hemorrhage (ICH) is a subtype of stroke with a high mortality rate. Oxidative stress cascades play an important role in brain injury after ICH. Cannabidiol, a major non-psychotropic phytocannabinoids, has drawn increasing interest in recent years as a potential therapeutic intervention for various neuropsychiatric disorders. Here we provide a comprehensive review of the potential therapeutic effects of cannabidiol in countering oxidative stress resulting from ICH. The review elaborates on the various sources of oxidative stress post-ICH, including mitochondrial dysfunction, excitotoxicity, iron toxicity, inflammation, and also highlights cannabidiol's ability to inhibit ROS/RNS generation from these sources. The article also delves into cannabidiol's role in promoting ROS/RNS scavenging through the Nrf2/ARE pathway, detailing both extranuclear and intranuclear regulatory mechanisms. Overall, the review underscores cannabidiol's promising antioxidant effects in the context of ICH and suggests its potential as a therapeutic option.

20.
Antioxidants (Basel) ; 12(10)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37891959

RESUMO

Numerous studies have established that the hypoxic conditions within ovarian follicles induce apoptosis in granulosa cells (GCs), a pivotal hallmark of follicular atresia. Melatonin (N-acetyl-5-methoxytryptamine, MT), a versatile antioxidant naturally present in follicular fluid, acts as a safeguard for maintaining GCs' survival during stress exposure. In this study, we unveil an innovative protective mechanism of melatonin against hypoxia-triggered GC apoptosis by selectively inhibiting mitochondrial ROS (mtROS) generation. Specifically, under hypoxic conditions, a gradual accumulation of mitochondrial ROS occurred, consequently activating the JNK-FOXO1 pathway, and driving GCs toward apoptosis. The blocking of JNK or FOXO1 diminished hypoxia-induced GC apoptosis, but this effect was nullified in the presence of GSH, indicating that mtROS instigates apoptosis through the JNK-FOXO1 pathway. Consistent with this, hypoxic GCs treated with melatonin exhibited decreased levels of mtROS, reduced JNK-FOXO1 activation, and mitigated apoptosis. However, the protective capabilities of melatonin were attenuated upon inhibiting its receptor MTNR1B, accompanied by the decreased expression of antioxidant genes. Notably, SOD2, a key mitochondrial antioxidant gene modulated by the melatonin-MTNR1B axis, effectively inhibited the activation of mtROS-JNK-FOXO1 and subsequent apoptosis, whereas SOD2 knockdown abrogated the protective role of melatonin in hypoxic GCs. In conclusion, our study elucidates that melatonin, through MTNR1B activation, fosters SOD2 expression, effectively quelling mtROS-JNK-FOXO1-mediated apoptosis in follicular GCs under hypoxic stress.

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