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1.
J Neurosci ; 44(11)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38331582

RESUMO

Cerebellum has been implicated in drug addiction; however, its underlying cellular populations and neuronal circuitry remain largely unknown. In the current study, we identified a neural pathway from tyrosine hydroxylase (TH)-positive Purkinje cells (PCTH+) in cerebellar lobule VI to calcium/calmodulin-dependent protein kinase II (CaMKII)-positive glutamatergic neurons in the medial cerebellar nucleus (MedCaMKII), forming the lobule VI PCTH+-MedCaMKII pathway in male mice. In naive male mice, inhibition of PCTH+ neurons activated Med neurons. During conditioned place preference (CPP) training, exposure to methamphetamine (METH) inhibited lobule VI PCTH+ neurons while excited MedCaMKII neurons in mice. Silencing MedCaMKII using a tetanus toxin light chain (tettox) suppressed the acquisition of METH CPP in mice but resulted in motor coordination deficits in naive mice. In contrast, activating lobule VI PCTH+ terminals within Med inhibited the activity of Med neurons and subsequently blocked the acquisition of METH CPP in mice without affecting motor coordination, locomotor activity, and sucrose reinforcements in naive mice. Our findings identified a novel lobule VI PCTH+-MedCaMKII pathway within the cerebellum and explored its role in mediating the acquisition of METH-preferred behaviors.


Assuntos
Estimulantes do Sistema Nervoso Central , Metanfetamina , Animais , Masculino , Camundongos , Metanfetamina/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Reforço Psicológico , Cerebelo/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia
2.
J Med Genet ; 61(6): 553-565, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38341271

RESUMO

BACKGROUND: The association between the TDRD6 variants and human infertility remains unclear, as only one homozygous missense variant of TDRD6 was found to be associated with oligoasthenoteratozoospermia (OAT). METHODS: Whole-exome sequencing and Sanger sequencing were employed to identify potential pathogenic variants of TDRD6 in infertile men. Histology, immunofluorescence, immunoblotting and ultrastructural analyses were conducted to clarify the structural and functional abnormalities of sperm in mutated patients. Tdrd6-knockout mice were generated using the CRISPR-Cas9 system. Total RNA-seq and single-cell RNA-seq (scRNA-seq) analyses were used to elucidate the underlying molecular mechanisms, followed by validation through quantitative RT-PCR and immunostaining. Intracytoplasmic sperm injection (ICSI) was also used to assess the efficacy of clinical treatment. RESULTS: Bi-allelic TDRD6 variants were identified in five unrelated Chinese individuals with OAT, including homozygous loss-of-function variants in two consanguineous families. Notably, besides reduced concentrations and impaired motility, a significant occurrence of acrosomal hypoplasia was detected in multiple spermatozoa among five patients. Using the Tdrd6-deficient mice, we further elucidate the pivotal role of TDRD6 in spermiogenesis and acrosome identified. In addition, the mislocalisation of crucial chromatoid body components DDX4 (MVH) and UPF1 was also observed in round spermatids from patients harbouring TDRD6 variants. ScRNA-seq analysis of germ cells from a patient with TDRD6 variants revealed that TDRD6 regulates mRNA metabolism processes involved in spermatid differentiation and cytoplasmic translation. CONCLUSION: Our findings strongly suggest that TDRD6 plays a conserved role in spermiogenesis and confirms the causal relationship between TDRD6 variants and human OAT. Additionally, this study highlights the unfavourable ICSI outcomes in individuals with bi-allelic TDRD6 variants, providing insights for potential clinical treatment strategies.


Assuntos
Alelos , Astenozoospermia , Sequenciamento do Exoma , Camundongos Knockout , Espermatogênese , Adulto , Animais , Humanos , Masculino , Camundongos , Acrossomo/patologia , Astenozoospermia/genética , Astenozoospermia/patologia , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Oligospermia/genética , Oligospermia/patologia , Linhagem , Injeções de Esperma Intracitoplásmicas , Espermatogênese/genética , Espermatozoides/patologia , Espermatozoides/metabolismo
3.
Biomacromolecules ; 25(7): 4469-4481, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38877974

RESUMO

A facile method was proposed for preparing controllable multicompartment gel microcarriers using an aqueous two-phase emulsion system. By leveraging the density difference between the upper polyethylene glycol solution and the lower dextran-calcium chloride (CaCl2) solution in the collection solution and the high viscosity of the lower solution, controllable fusion of core-shell droplets made by coextrusion devices was achieved at the water/water (w/w) interface to fabricate microcarriers with separated core compartments. By adjusting the sodium alginate concentration, collected solution composition, and number of fused liquid droplets, the pore size, shape, and number of compartments could be controlled. Caco-2 and HepG2 cells were encapsulated in different compartments to establish gut-liver coculture models, exhibiting higher viability and proliferation compared to monoculture models. Notably, significant differences in cytokine expression and functional proteins were observed between the coculture and monoculture models. This method provides new possibilities for preparing complex and functional three-dimensional coculture materials.


Assuntos
Alginatos , Técnicas de Cocultura , Emulsões , Humanos , Técnicas de Cocultura/métodos , Células Hep G2 , Emulsões/química , Células CACO-2 , Alginatos/química , Géis/química , Polietilenoglicóis/química , Cloreto de Cálcio/química , Dextranos/química , Proliferação de Células , Sobrevivência Celular
4.
Cell Mol Biol Lett ; 29(1): 37, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486171

RESUMO

BACKGROUND: DNA mismatch repair (MMR) is a highly conserved pathway that corrects DNA replication errors, the loss of which is attributed to the development of various types of cancers. Although well characterized, MMR factors remain to be identified. As a 3'-5' exonuclease and endonuclease, meiotic recombination 11 homolog A (MRE11A) is implicated in multiple DNA repair pathways. However, the role of MRE11A in MMR is unclear. METHODS: Initially, short-term and long-term survival assays were used to measure the cells' sensitivity to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Meanwhile, the level of apoptosis was also determined by flow cytometry after MNNG treatment. Western blotting and immunofluorescence assays were used to evaluate the DNA damage within one cell cycle after MNNG treatment. Next, a GFP-heteroduplex repair assay and microsatellite stability test were used to measure the MMR activities in cells. To investigate the mechanisms, western blotting, the GFP-heteroduplex repair assay, and chromatin immunoprecipitation were used. RESULTS: We show that knockdown of MRE11A increased the sensitivity of HeLa cells to MNNG treatment, as well as the MNNG-induced DNA damage and apoptosis, implying a potential role of MRE11 in MMR. Moreover, we found that MRE11A was largely recruited to chromatin and negatively regulated the DNA damage signals within the first cell cycle after MNNG treatment. We also showed that knockdown of MRE11A increased, while overexpressing MRE11A decreased, MMR activity in HeLa cells, suggesting that MRE11A negatively regulates MMR activity. Furthermore, we show that recruitment of MRE11A to chromatin requires MLH1 and that MRE11A competes with PMS2 for binding to MLH1. This decreases PMS2 levels in whole cells and on chromatin, and consequently comprises MMR activity. CONCLUSIONS: Our findings reveal that MRE11A is a negative regulator of human MMR.


Assuntos
Reparo de Erro de Pareamento de DNA , Metilnitronitrosoguanidina , Humanos , Cromatina , Células HeLa , Metilnitronitrosoguanidina/farmacologia , Endonuclease PMS2 de Reparo de Erro de Pareamento
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(4): 458-461, 2023 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-36972942

RESUMO

OBJECTIVE: To analyze variant of LDLR gene in a patient with familial hypercholesterolemia (FH) in order to provide a basis for the clinical diagnosis and genetic counseling. METHODS: A patient who had visited the Reproductive Medicine Center of the First Affiliated Hospital of Anhui Medical University in June 2020 was selected as the study subject. Clinical data of the patient was collected. Whole exome sequencing (WES) was applied to the patient. Candidate variant was verified by Sanger sequencing. Conservation of the variant site was analyzed by searching the UCSC database. RESULTS: The total cholesterol level of the patient was increased, especially low density lipoprotein cholesterol. A heterozygous c.2344A>T (p.Lys782*) variant was detected in the LDLR gene. Sanger sequencing confirmed that the variant was inherited from the father. CONCLUSION: The heterozygous c.2344A>T (p.Lys782*) variant of the LDLR gene probably underlay the FH in this patient. Above finding has provided a basis for genetic counseling and prenatal diagnosis for this family.


Assuntos
Hiperlipoproteinemia Tipo II , Receptores de LDL , Humanos , LDL-Colesterol/genética , Heterozigoto , Hiperlipoproteinemia Tipo II/genética , Mutação , Linhagem , Fenótipo , Receptores de LDL/genética
6.
Hum Mutat ; 43(12): 2079-2090, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36135717

RESUMO

Asthenoteratozoospermia is the primary cause of infertility in humans. However, the genetic etiology remains largely unknown for those suffering from severe asthenoteratozoospermia caused by thin midpiece defects. In this study, we identified two biallelic loss-of-function variants of SEPTIN4 (previously SEPT4) (Patient 1: c.A721T, p.R241* and Patient 2: c.C205T, p.R69*) in two unrelated individuals from two consanguineous Chinese families. SEPT4 is a conserved annulus protein that is critical for male fertility and the structural integrity of the sperm midpiece in mice. SEPT4 mutations disrupted the formation of SEPT-based annulus and localization of SEPTIN subunits in sperms from patients. The ultrastructural analysis demonstrated striking thin midpiece spermatozoa defects owing to annulus loss and disorganized mitochondrial sheath. Immunofluorescence and immunoblotting analyses of the mitochondrial sheath proteins TOMM20 and HSP60 further indicated that the distribution and abundance of mitochondria were impaired in men harboring biallelic SEPT4 variants. Additionally, we found that the precise localization of SLC26A8, a testis-specific anion transporter that colocalizes with SEPT4 at the sperm annulus, was missing without SEPT4. Moreover, the patient achieved a good pregnancy outcome following intracytoplasmic sperm injection. Overall, our study demonstrated for the first time that SEPT4 variants that induced thin midpiece spermatozoa defects were directly associated with human asthenoteratozoospermia.


Assuntos
Astenozoospermia , Infertilidade Masculina , Septinas , Feminino , Humanos , Masculino , Gravidez , Astenozoospermia/genética , Astenozoospermia/metabolismo , Infertilidade Masculina/genética , Proteínas/metabolismo , Sêmen/metabolismo , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/ultraestrutura , Espermatozoides , Septinas/genética
7.
Hum Genet ; 141(11): 1795-1809, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35587281

RESUMO

Non-obstructive azoospermia (NOA) and premature ovarian insufficiency (POI) represent the most serious forms of human infertility caused by gametogenic failure. Although whole-exome sequencing (WES) has uncovered multiple monogenic causes of human infertility, our knowledge of the genetic basis of human gametogenesis defects remains at a rudimentary stage. Coiled-coil-domain-containing protein 155 (CCDC155) encodes a core component of the linker of the nucleoskeleton and cytoskeleton complex that is essential for modulating telomere-led chromosome movements during the meiotic prophase of mice. Additionally, Ccdc155 deficiency in mice causes infertility in both sexes with meiotic arrest. In this study, we applied WES to identify the pathogenic genes for 15 NOA and POI patients whose parents were consanguineous and identified a novel homozygous missense mutation in CCDC155 [c.590T>C (p.Leu197Pro)] in a pair of familial NOA and POI patients whose parents were first cousins. The affected spermatocytes were unable to complete meiotic division coupled with unresolved repair of the DNA double-strand break. This rare missense mutation with lesions in the conserved CC domain of CCDC155 blocked nuclear envelope (NE) distribution and subsequently prevented NE-specific enrichment of Sad1- and UNC84-domain-containing 1 either ex vivo or in vitro, eventually leading to disruptive NE anchoring of chromosome-induced meiotic arrest in both sexes. This study presents the first evidence of the necessity of the SUN1-CCDC155 complex during human meiosis and provides insight into the CCDC155 CC domain, thereby expanding the genetic spectrum of human NOA and POI and promoting adequate genetic counselling and appropriate fertility guidance for these patients.


Assuntos
Azoospermia , Proteínas de Ciclo Celular/genética , Insuficiência Ovariana Primária , Animais , Azoospermia/genética , Azoospermia/patologia , DNA , Feminino , Homozigoto , Humanos , Masculino , Meiose , Proteínas de Membrana/genética , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Mutação , Mutação de Sentido Incorreto , Proteínas Nucleares/genética , Insuficiência Ovariana Primária/genética
8.
Clin Genet ; 101(1): 55-64, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34595750

RESUMO

Non-obstructive azoospermia (NOA) represents one of the most serious forms of male infertility caused by spermatogenic failure. Despite multiple genes found to be associated with human NOA, the genetic basis of this idiopathic disease remains largely unknown. FBXO43 is a direct inhibitor of the anaphase-promoting complex/cyclosome (APC/C) E3 ligase and crucially important in mouse spermatogenesis. In this study, for the first time, we identified a homozygous nonsense mutation in FBXO43 c.1747C > T:p.Gln583X in two NOA brothers from a Chinese consanguineous family via whole-exome sequencing. FBXO43 was absent from testicular tissue of the proband, and FBXO43-immunostaining signals were invisible in the affected seminiferous tubules. Furthermore, in humans, FBXO43 defects cause meiotic arrest within early diplotene of prophase I. The results here demonstrate the pathogenicity of this loss-of-function mutation and confirmed that spermatocytes were unable to complete meiotic divisions without FBXO43 in humans. In mouse testicular protein extracts, three subunits of the APC/C, including ANAPC2, ANAPC8 and ANAPC10, were validated to interact directly with FBXO43, whereas no interactions were detected for FBXO43 and SKP1. This study furthers our understanding of the genetic basis of human NOA and provides insights into FBXO43 and male infertility.


Assuntos
Azoospermia/diagnóstico , Azoospermia/genética , Proteínas F-Box/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Homozigoto , Mutação com Perda de Função , Animais , Biomarcadores , China , Consanguinidade , Análise Mutacional de DNA , Modelos Animais de Doenças , Estudos de Associação Genética/métodos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Linhagem , Análise do Sêmen , Análise de Sequência de DNA , Testículo/metabolismo , Sequenciamento do Exoma
9.
Reprod Biol Endocrinol ; 20(1): 63, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366911

RESUMO

BACKGROUND: Non-obstructive azoospermia (NOA) is the most severe type of male infertility, affecting 1% of men worldwide. Most of its etiologies remain idiopathic. Although genetic studies have identified dozens of NOA genes, monogenic mutations can also account for a small proportion of idiopathic NOA cases. Hence, this genetic study was conducted to explore the causes of monogenic variants of NOA in a cohort of Chinese patients. METHODS: Following the screening using chromosomal karyotyping, Y chromosome microdeletion analyses, and sex hormone assessments, subsequent whole-exome sequencing analysis was performed in 55 unrelated idiopathic NOA patients with male infertility to explore potential deleterious variants associated with spermatogenesis. We also performed Sanger sequencing to demonstrate the variants. Testicular biopsy or microsurgical testicular sperm extraction was also performed to confirm the diagnosis of NOA and identify spermatozoa. Hematoxylin and eosin staining was performed to assess the histopathology of spermatogenesis. RESULTS: Abnormal testicular pathological phenotypes included Sertoli cell-only syndrome, maturation arrest, and hypospermatogenesis. Using bioinformatics analysis, we detected novel variants in two recessive genes, FANCA (NM_000135, c.3263C > T, c.1729C > G) and SYCE1 (NM_001143763, c.689_690del); one X-linked gene, TEX11 (NM_031276, c.466A > G, c.559_560del); and two dominant genes, DMRT1 (NM_021951, c.425C > T, c.340G > A) and PLK4 (NM_001190799, c.2785A > G), in eight patients, which corresponded to 14.55% (8/55) of the patients. CONCLUSION: This study presented some novel variants of known pathogenic genes for NOA. Further, it expanded the variant spectrum of NOA patients, which might advance clinical genetic counseling in the future.


Assuntos
Azoospermia , Infertilidade Masculina , Oligospermia , Azoospermia/diagnóstico , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Masculino , Proteínas Serina-Treonina Quinases , Espermatogênese/genética , Testículo/patologia
10.
Reprod Biol Endocrinol ; 20(1): 41, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232447

RESUMO

BACKGROUND: Multiple morphological abnormalities of the sperm flagella (MMAF) is a subtype of severe asthenoteratozoospermia with poorly understood genetic etiology. SPAG6 is a core axonemal component that plays a critical role in the formation of cilia and sperm flagella. Previous studies have reported that mutations in SPAG6 cause primary ciliary dyskinesia (PCD), but the association between SPAG6 gene variants and the MMAF phenotype has not yet been described. METHODS: We performed whole-exome sequencing (WES) in two unrelated Han Chinese men with MMAF. Sanger sequencing was used to validate the candidate variants. Routine semen analysis was carried out according to the WHO guidelines (5th Edition). Sperm morphology was assessed using modified Papanicolaou staining. Scanning and transmission electron microscopy (S/TEM) was performed to observe the ultrastructural defects of the sperm flagella. Western blot analysis and immunofluorescence (IF) of spermatozoa were performed to examine the expression of SPAG6 protein. Assisted fertilization with intracytoplasmic sperm injection (ICSI) was applied. RESULTS: Two homozygous SPAG6 variants were identified by WES and Sanger validation in two patients with MMAF phenotype (F1 II-1: c.308C > A, p. A103D; F2 II-1: c. 585delA, p. K196Sfs*6). Semen analysis showed progressive rates of less than 1%, and most of the spermatozoa presented MMAF by Papanicolaou staining. TEM revealed that the overall axonemal ultrastructure was disrupted and primarily presented an abnormal "9 + 0" configuration. No other PCD-related symptoms were found on physical examination and medical consultations, as well as lung CT screening. The level of SPAG6 protein was significantly decreased in the spermatozoa, and IF analysis revealed that SPAG6 staining was extremely weak and discontinuous in the sperm flagella of the two patients. Notably, F1 II-1 and his wife conceived successfully after undergoing ICSI. CONCLUSIONS: Our research provides new evidence for a potential correlation between SPAG6 variants and the MMAF phenotype.


Assuntos
Astenozoospermia/genética , Proteínas dos Microtúbulos/genética , Teratozoospermia/genética , Adulto , Astenozoospermia/complicações , Astenozoospermia/patologia , China , Consanguinidade , Análise Mutacional de DNA/métodos , Homozigoto , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Masculino , Mutação , Linhagem , Fenótipo , Cauda do Espermatozoide/patologia , Cauda do Espermatozoide/ultraestrutura , Espermatozoides/anormalidades , Espermatozoides/ultraestrutura , Teratozoospermia/complicações , Teratozoospermia/patologia , Sequenciamento do Exoma
11.
J Assist Reprod Genet ; 39(1): 251-259, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34657236

RESUMO

PURPOSE: Multiple morphological abnormalities in the sperm flagella (MMAF) comprise a severe phenotype of asthenoteratozoospermia with reduced or absent spermatozoa motility. Whereas dozens of candidate pathogenic genes for MMAF have been identified, the genetic cause in a large proportion of patients is unknown. We attempted to identify novel genetic explanations for MMAF. METHODS: We performed whole-exome sequencing of patients with MMAF to identify pathogenic variants. The phenotypes of spermatozoa in patients carrying DNAH10 variants were investigated using haematoxylin and eosin staining, scanning electron microscopy, and transmission electron microscopy. The expression and location of DNAH10 and other spermatozoa structure-related proteins were analyzed using immunofluorescence assays. RESULTS: We found one homozygous frameshift DNAH10 variant (NM_207437: c.2514delG:p.L839*) and one compound heterozygous DNAH10 variant (NM_207437: c.10820 T > C:p.M3607T; c.12692C > T:p.T4231I) in two patients with MMAF. These variants were absent or rare in the general population. Haematoxylin and eosin staining and scanning electron microscopy revealed the significant disruption of sperm flagella in the patients. In addition, ultrastructural analysis by transmission electron microscopy showed significant inner dynein arm (IDA) deficiency in sperm flagella. Using immunofluorescence assays, we found a significant reduction in IDA-related proteins including DNAH10 and DNAH1. CONCLUSIONS: We identified putative novel pathogenic variants in DNAH10 for MMAF, which might advance the genetic diagnosis and clinical genetic counselling for male infertility.


Assuntos
Astenozoospermia/etiologia , Dineínas/genética , Adulto , Astenozoospermia/genética , Dineínas/efeitos adversos , Dineínas/metabolismo , Variação Genética/genética , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Masculino , Espermatozoides/patologia , Sequenciamento do Exoma/métodos
12.
J Med Internet Res ; 23(2): e25342, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33629964

RESUMO

BACKGROUND: The gut microbiome is receiving considerable attention as a potentially modifiable risk factor and therapeutic target for numerous mental and neurological diseases. OBJECTIVE: This study aimed to explore and assess the difference in the composition of gut microbes and fecal metabolites between women with hypoactive sexual desire disorder (HSDD) and healthy controls. METHODS: We employed an online recruitment method to enroll "hard-to-reach" HSDD populations. After a stringent diagnostic and exclusion process based on DSM-IV criteria, fecal samples collected from 24 women with HSDD and 22 age-matched, healthy controls underwent microbiome analysis using 16S ribosomal RNA gene sequencing and metabolome analysis using untargeted liquid chromatography-mass spectrometry. RESULTS: We found a decreased abundance of Ruminococcaceae and increased abundance of Bifidobacterium and Lactobacillus among women with HSDD. Fecal samples from women with HSDD showed significantly altered metabolic signatures compared with healthy controls. The abundance of Bifidobacterium, Lactobacillus, and several fecal metabolites correlated negatively with the sexual desire score, while the number of Ruminococcaceae correlated positively with the sexual desire score in all subjects. CONCLUSIONS: Our analysis of fecal samples from women with HSDD and healthy controls identified significantly different gut microbes and metabolic signatures. These preliminary findings could be useful for developing strategies to adjust the level of human sexual desire by modifying gut microbiota. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1800020321; http://www.chictr.org.cn/showproj.aspx?proj=34267.


Assuntos
Microbioma Gastrointestinal/fisiologia , Disfunções Sexuais Psicogênicas/etiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Projetos de Pesquisa , Disfunções Sexuais Psicogênicas/microbiologia
13.
Phys Chem Chem Phys ; 22(39): 22260-22270, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33001131

RESUMO

Identifying the structural response of nanoparticle-support ensembles to the reaction conditions is essential to determine their structure in the catalytically active state as well as to unravel the possible degradation pathways. In this work, we investigate the (electronic) structure of carbon- and oxide-supported Pt nanoparticles during electrochemical oxidation by in situ X-ray diffraction, absorption spectroscopy as well as the Pt dissolution rate by in situ mass spectrometry. We prepared ellipsoidal Pt nanoparticles by impregnation of the carbon and titanium-based oxide support as well as spherical Pt nanoparticles on an indium-based oxide support by a surfactant-assisted synthesis route. During electrochemical oxidation, we show that the oxide-supported Pt nanoparticles resist (bulk) oxide formation and Pt dissolution. The lattice of smaller Pt nanoparticles exhibits a size-induced lattice contraction in the as-prepared state with respect to bulk Pt but it expands reversibly during electrochemical oxidation. This expansion is suppressed for the Pt nanoparticles with a bulk-like relaxed lattice. We could correlate the formation of d-band vacancies in the metallic Pt with Pt lattice expansion. PtOx formation is strongest for platelet-like nanoparticles and we explain this with a higher fraction of exposed Pt(100) facets. Of all investigated nanoparticle-support ensembles, the structural response of RuO2/TiO2-supported Pt nanoparticles is the most promising with respect to their morphological and structural integrity under electrochemical reaction conditions.

16.
Psychopharmacology (Berl) ; 241(5): 897-911, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38092953

RESUMO

RATIONALE: Methamphetamine (METH) exposure has toxicity in sperm epigenetic phenotype and increases the risk for developing addiction in their offspring. However, the underlying transgenerational mechanism remains unclear. OBJECTIVES: The current study aims to investigate the profiles of sperm epigenetic modifications in male METH-exposed mice (F0) and medial prefrontal cortex (mPFC) transcriptome in their male first-generation offspring (F1). METHODS: METH-related male F0 and F1 mice model was established to investigate the effects of paternal METH exposure on reproductive functions and sperm DNA methylation in F0 and mPFC transcriptomic profile in F1. During adulthood, F1 was subjected to a conditioned place preference (CPP) test to evaluate sensitivity to METH. The gene levels were verified with qPCR. RESULTS: METH exposure obviously altered F0 sperms DNA methylated profile and male F1 mPFC transcriptomic profile, many of which being related to neuronal system and brain development. In METH-sired male F1, subthreshold dose of METH administration effectively elicited CPP, along with more mPFC activation. After qPCR verification, Sort1 and Shank2 were at higher levels in F0 sperm and F1 mPFC. CONCLUSIONS: Our findings put new insights into paternal METH exposure-altered profiles of F0 sperm DNA methylation and male F1 mPFC transcriptomics. Several genes, such as Sort1 and Shank2, might be used as potential molecules for further research on the transgenerational vulnerability to drug addiction in offspring by paternal drug exposure.

17.
ACS Appl Mater Interfaces ; 16(24): 31597-31609, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38850560

RESUMO

By overcoming interspecies differences and mimicking the in vivo microenvironment, three-dimensional (3D) in vitro corneal models have become a significant novel tool in contemporary ophthalmic disease research. However, existing 3D corneal models struggle to replicate the actual human corneal environment, especially the dome-shaped physiological structure with adjustable curvature. Addressing these challenges, this study introduces a straightforward method for fabricating collagen/chitosan-alginate eyeball-shaped gel microspheres with a Janus structure via a two-phase aqueous system, used subsequently to construct in vitro 3D corneal epithelial tissue models. By adjusting the diameter ratio of collagen/chitosan to alginate droplets, we can create eyeball-shaped gel microspheres with varying curvatures. Human corneal epithelial cells were seeded on the surfaces of these microspheres, leading to the formation of in vitro 3D corneal epithelial tissues characterized by dome-like multilayers and tight junctions. Additionally, the model demonstrated responsiveness to UVB exposure through the secretion of reactive oxygen species (ROS) and proinflammatory factors. Therefore, we believe that in vitro 3D corneal epithelial tissue models with dome-shaped structures hold significant potential for advancing ophthalmic research.


Assuntos
Alginatos , Quitosana , Epitélio Corneano , Microesferas , Humanos , Epitélio Corneano/citologia , Alginatos/química , Quitosana/química , Colágeno/química , Engenharia Tecidual , Células Epiteliais/metabolismo , Células Epiteliais/citologia , Géis/química , Espécies Reativas de Oxigênio/metabolismo
18.
Biomed Mater ; 19(3)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38574669

RESUMO

Recently,in vitromodels of intestinal mucosa have become important tools for drug screening and studying the physiology and pathology of the intestine. These models enable the examination of cellular behavior in diseased states or in reaction to alterations in the microenvironment, potentially serving as alternatives to animal models. One of the major challenges in constructing physiologically relevantin vitromodels of intestinal mucosa is the creation of three-dimensional microstructures that accurately mimic the integration of intestinal epithelium and vascularized stroma. Here, core-shell alginate (Alg) microspheres were generated to create the compartmentalized extracellular matrix microenvironment needed to simulate the epithelial and vascularized stromal compartments of the intestinal mucosa. We demonstrated that NIH-3T3 and human umbilical vein endothelial cells embedded in the core of the microspheres can proliferate and develop a vascular network, while human colorectal adenocarcinoma cells (Caco-2) can form an epithelial monolayer in the shell. Compared to Caco-2 monolayer encapsulated within the shell, the presence of the vascularized stroma enhances their proliferation and functionality. As such, our core-shell Alg microspheres provide a valuable method for generatingin vitromodels of vascularized intestinal mucosa with epithelial and vascularized stroma arranged in a spatially relevant manner and demonstrating near-physiological functionality.


Assuntos
Alginatos , Proliferação de Células , Células Endoteliais da Veia Umbilical Humana , Mucosa Intestinal , Microesferas , Engenharia Tecidual , Alginatos/química , Humanos , Mucosa Intestinal/metabolismo , Animais , Camundongos , Células CACO-2 , Engenharia Tecidual/métodos , Células NIH 3T3 , Matriz Extracelular/metabolismo , Alicerces Teciduais/química , Ácidos Hexurônicos/química
19.
Syst Biol Reprod Med ; 70(1): 150-163, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38896558

RESUMO

The incidence of male infertility (MI) is rising annually. However, the lifestyle and occupational exposure factors contributing to MI remain incompletely understood. This study explored the effects of self-reported lifestyle and occupational exposure factors on semen quality. Among 1060 subjects invited to participate, 826 were eligible. The participants' general characteristics, lifestyle, and occupational exposure factors were collected immediately before or after semen evaluation through an online questionnaire. Initially, univariate analysis was used to investigate the relationship between the abovementioned factors and semen quality. The results indicated significant associations between low semen quality and various factors, including age, BMI, infertility type and duration, abstinence time, semen and sperm parameters, smoking, alcohol consumption, irregular sleep habits, and frequent exposure to high temperatures and chemicals at work (p < 0.05). Then, multivariate analysis was conducted to identify factors independently associated with low semen quality. Adjustment for relevant confounders was achieved by including factors with a p-value < 0.25 from univariate analyses as covariates in the binomial and ordered logistic regression models. The results suggested that alcohol consumption was a positive factor for sperm concentration (odds ratio [OR] = 0.60; 95% confidence interval [CI] = 0.36-0.99; p = 0.045). The groups with a BMI ≥ 24 and <28 kg/m2 showed a significant decrease in sperm progressive motility when compared to the reference group (BMI < 24 kg/m2) (OR = 0.63; 95% CI = 0.46-0.87, p = 0.005). In addition, the groups that drank green tea <1 time/week (OR = 1.52, 95% CI = 1.05-2.2) and 1-4 times/week (OR = 1.61, 95% CI = 1.02-2.54) exhibited significantly increased sperm DFI values compared with the group that drank green tea 5-7 times/week. In conclusion, these findings underscore the importance of maintaining a normal weight and regularly consuming green tea for men.


Assuntos
Infertilidade Masculina , Estilo de Vida , Exposição Ocupacional , Análise do Sêmen , Humanos , Masculino , Adulto , Exposição Ocupacional/efeitos adversos , Estudos Transversais , Infertilidade Masculina/etiologia , Infertilidade Masculina/epidemiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Fatores de Risco , Pessoa de Meia-Idade , Motilidade dos Espermatozoides , Contagem de Espermatozoides
20.
Sci China Life Sci ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38761355

RESUMO

The complexities of energy transfer mechanisms in the flagella of mammalian sperm flagella have been intensively investigated and demonstrate significant diversity across species. Enzymatic shuttles, particularly adenylate kinase (AK) and creatine kinase (CK), are pivotal in the efficient transfer of intracellular ATP, showing distinct tissue- and species-specificity. Here, the expression profiles of AK and CK were investigated in mice and found to fall into four subgroups, of which Subgroup III AKs were observed to be unique to the male reproductive system and conserved across chordates. Both AK8 and AK9 were found to be indispensable to male reproduction after analysis of an infertile male cohort. Knockout mouse models showed that AK8 and AK9 were central to promoting sperm motility. Immunoprecipitation combined with mass spectrometry revealed that AK8 and AK9 interact with the radial spoke (RS) of the axoneme. Examination of various human and mouse sperm samples with substructural damage, including the presence of multiple RS subunits, showed that the head of radial spoke 3 acts as an adapter for AK9 in the flagellar axoneme. Using an ATP probe together with metabolomic analysis, it was found that AK8 and AK9 cooperatively regulated ATP transfer in the axoneme, and were concentrated at sites associated with energy consumption in the flagellum. These findings indicate a novel function for RS beyond its structural role, namely, the regulation of ATP transfer. In conclusion, the results expand the functional spectrum of AK proteins and suggest a fresh model regarding ATP transfer within mammalian flagella.

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