RESUMO
Defective spermatogenesis is prevalent in infertile men, but the molecular mechanisms underlying its aetiology are largely unknown. In this study, a proposed association between IκBα SNPs, smoking-related ROS and sperm quality was investigated. Two polymorphisms in the IκBα gene, rs2233406 and rs696 were genotyped in 342 controls and 338 patients with defective spermatogenesis from a southern Chinese population. The results showed the rs696 AA genotype to be significantly more common (21.60% versus 14.33%, P = 0.013) and the rs696 GG genotype to be significantly rarer (28.99% versus 37.13%, P = 0.024) in the cases than in the controls. After subjects were stratified into smokers and nonsmokers, these differences were only observed in nonsmokers. Further analysis showed the rs696 AA genotype to be significantly closely associated with defective spermatogenesis in all subjects (P = 0.014, OR = 1.647) and in nonsmokers (P = 0.036, OR = 1.889). In a TM3 cell model, exposure to cigarette smoke condensate was found to activate NF-κB luciferase activity and altered transcriptional level of NF-κB pathway genes. In conclusion, this study demonstrates an association between functional polymorphisms of the IκBα rs696 and cigarette smoking with the risk of defective spermatogenesis, suggesting some interaction between the NF-κB signalling pathway and smoking-related ROS in human spermatogenesis.
Assuntos
Astenozoospermia/genética , Interação Gene-Ambiente , Proteínas I-kappa B/genética , Oligospermia/genética , Fumar/epidemiologia , Adulto , Animais , Povo Asiático/genética , Povo Asiático/estatística & dados numéricos , Astenozoospermia/epidemiologia , Estudos de Casos e Controles , Linhagem Celular , China/epidemiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B/efeitos dos fármacos , NF-kappa B/genética , Oligospermia/epidemiologia , Polimorfismo de Nucleotídeo Único , Espécies Reativas de Oxigênio , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise do Sêmen , Transdução de Sinais/genética , Fumaça/efeitos adversos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatogênese/efeitos dos fármacos , Nicotiana/efeitos adversosRESUMO
Titanium dioxide nanoparticles (TiO2 NPs) can reduce sperm number, but the mechanisms of defective spermatogenesis induced by TiO2 NPs have not been studied through cell-cell interactions at present. A kind of biomimetic three-dimensional blood-testis barrier microfluidic chip capable of intercellular communication was constructed with soft lithography techniques, including Sertoli cell (TM4), spermatogonia (GC-1) and vascular endothelial cell units, to study the mechanisms of TiO2 NPs-induced defective spermatogenesis. TM4 and GC-1 cells cultured in TiO2 NPs exposure and control chips were collected for transcriptomics and metabonomics analysis, and key proteins and metabolites in changed biological processes were validated. In TM4 cells, TiO2 NPs suppressed glucose metabolism, especially lactate production, which reduced energy substrate supply for spermatogenesis. TiO2 NPs also decreased the levels of key proteins and metabolites of lactate production. In GC-1 cells, TiO2 NPs disturbed chemokine signaling pathways regulating cell proliferation and interfered with glutathione metabolism. The Cxcl13, Stat3 and p-Stat3 levels and cell proliferation rate were decreased, and the GSR, GPX4 and GSH contents were increased in GC-1 cells in chips under TiO2 NPs treatment. The decrease in energy substrate supply for spermatogenesis and inhibition of spermatogonia proliferation could be the main mechanisms of defective spermatogenesis induced by TiO2 NPs.
Assuntos
Barreira Hematotesticular , Células de Sertoli , Espermatogênese , Espermatogônias , Titânio , Masculino , Titânio/toxicidade , Espermatogênese/efeitos dos fármacos , Animais , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Barreira Hematotesticular/efeitos dos fármacos , Camundongos , Espermatogônias/efeitos dos fármacos , Espermatogônias/metabolismo , Espermatogônias/patologia , Linhagem Celular , Nanopartículas Metálicas/toxicidade , Dispositivos Lab-On-A-Chip , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Comunicação Celular/efeitos dos fármacosRESUMO
OBJECTIVE: To investigate the association between smoking, semen quality, and the histone-to-protamine transition ratio in mature sperm. DESIGN: Biochemical and molecular analysis in human samples and a cell line. SETTING: Andrology laboratory in a university-affiliated hospital. PATIENT(S): Semen samples from 147 heavy smokers and 175 nonsmokers receiving infertility treatment. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Basic semen parameters, histone-to-protamine ratios, and number of sperm cells with abnormal histone transition were calculated. The relative messenger RNA (mRNA) expression levels of protamine 1 and protamine 2 were assayed in human sperm and in TM3 cells exposed to cigarette smoke condensate. T tests, Spearman tests, and nonparametric Mann-Whitney U tests were used to detect significant differences. RESULT(S): Normozoospermic smokers had significantly higher abnormalities than their nonsmoking counterparts. Sperm histone replacement abnormalities were found to be closely correlated with sperm motility, viability, concentration, counts, and cotinine levels. The ratios of protamine 1 to protamine 2 mRNA expression significantly increased in heavy smokers and in TM3 cells treated with cigarette smoke condensate. CONCLUSION(S): Smoking is strongly associated with abnormalities in histone-to-protamine transition and with alteration of protamine mRNA expression in human sperm.