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1.
Andrologia ; 54(11): e14592, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36123798

RESUMO

In this study, the effect of 14 weeks of standard diet (controls) or folate and vitamin B12-free diet (VBD group) or vitamin D-free diet (VDD group) were assessed on mice testicular function, and sperm function. Vitamin D deprivation caused increased body weight with no effect from VBD confirming the calcium-independent role of vitamin D on body weight homeostasis. The two deprivations caused convergent damages including decreased testosterone, worsened Johnson scores, tubular differentiation index and spermatogenesis index, and serious worsening of sperm parameters and of sperm functional tests (DNA methylation, protamination, DNA damage and lipid peroxidation). From a metabolic point of view, the damage from both models converged on the one carbon cycle (methylations) and the transsulfuration pathway (GSH and antioxidant defences) and increased circulating homocysteine, although with different mechanisms: VBD appeared to hamper methylations due to lower ability to regenerate homocysteine to methionine whereas VDD appeared to interfere with homocysteine transsulfuration to cysteine and, thereafter, GSH. VDD also caused a huge paradox increase of vitamin B12, which was likely in a non-functional form and warrants further investigation. These findings strongly endorse the potential benefit of combined folate/B12 and vitamin D supplementation in infertile patients.


Assuntos
Sêmen , Vitamina B 12 , Animais , Masculino , Camundongos , Ácido Fólico , Espermatozoides , Vitaminas , Suplementos Nutricionais , Peso Corporal , Homocisteína
2.
Reprod Biomed Online ; 41(6): 1084-1091, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33032908

RESUMO

RESEARCH QUESTION: Does supplementation with alpha-lipoic acid (ALA) enhance sperm parameters and/or the status of sperm lipid peroxidation and DNA fragmentation in men who have undergone microsurgical repair of a varicocele? DESIGN: Individuals with a varicocele who had undergone varicocelectomy were divided into two groups receiving either 600 mg of ALA or an identical placebo for 80 days. Semen samples obtained from the participants before surgery and after completion of the course of medication were analysed and compared. Participants, clinicians and data analysts were blinded to the randomization sequence. RESULTS: In the ALA group, total motility (P = 0.01) and progressive motility (P = 0.002) of the spermatozoa were significantly higher compared with the placebo group after surgery. Sperm lipid peroxidation and DNA damage (assessed by sperm chromatin structure assay) showed significant decreases in both the ALA and placebo groups (P ≤ 0.02) after treatment. CONCLUSIONS: An 80-day course of ALA medication after surgical repair improves total motility and progressive motility of the spermatozoa in individuals with a varicocele.


Assuntos
Motilidade dos Espermatozoides/efeitos dos fármacos , Ácido Tióctico/farmacologia , Varicocele/dietoterapia , Varicocele/cirurgia , Adulto , Terapia Combinada , Dano ao DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Infertilidade Masculina/dietoterapia , Infertilidade Masculina/etiologia , Infertilidade Masculina/cirurgia , Masculino , Microcirurgia , Pessoa de Meia-Idade , Período Pós-Operatório , Análise do Sêmen , Motilidade dos Espermatozoides/genética , Procedimentos Cirúrgicos Urogenitais , Varicocele/complicações , Adulto Jovem
3.
Andrologia ; 51(5): e13249, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30873668

RESUMO

Intracytoplasmic sperm injection (ICSI) is a technique developed to help attain successful fertilisation for couples with severe male factor. However, a small percentage of couples confront low or failed fertilisation, mainly due to failed oocyte activation. Several studies have introduced phospholipase Cζ (PLCζ) as the main sperm factor inducing oocyte activation and thereby has the potential to act as a biomarker for the prediction of ICSI fertilisation outcome. On the other hand, researchers have focused on novel sperm selection procedures based on cellular characteristics of spermatozoa such as surface electrical charge (Zeta potential) to isolate normal sperm subpopulation with intact chromatin. Therefore, we aimed to compare PLCζ between Zeta method and routine sperm preparation procedure: density gradient centrifugation (DGC). Our results showed that number of PLCζ-positive spermatozoa was significantly low in the Zeta method, but the intensity of PLCζ protein in such spermatozoa was significantly higher than DGC procedure. Therefore, the combination of DGC with Zeta procedure may allow selecting the population of spermatozoa with a high percentage of PLCζ which may also contain a high amount of PLCζ and with intact chromatin. This sperm selection procedure can open a new approach for infertile men with previously failed fertilisation.


Assuntos
Oócitos/fisiologia , Fosfoinositídeo Fosfolipase C/metabolismo , Análise do Sêmen/métodos , Espermatozoides/metabolismo , Centrifugação com Gradiente de Concentração , Humanos , Infertilidade Masculina/terapia , Masculino , Fosfoinositídeo Fosfolipase C/análise , Injeções de Esperma Intracitoplásmicas , Eletricidade Estática
4.
Int J Biol Macromol ; 130: 863-877, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30849467

RESUMO

Organic osmolytes, as major cellular compounds, cause protein stabilization in the native form. In the present study, the possible chaperone effects of the three naturally occurring osmolytes on the two-chain form of tenecteplase (tc-TNK), a recombinant, genetically engineered mutant tissue plasminogen activator, have been explored by using circular dichroism, steady-state fluorescence, UV-Visible spectroscopy, and in silico experiments. The tc-TNK is derived from the one-chain protein upon disruption of one peptide bond. Thermal denaturation experiments showed a slightly more stabilizing effect of the three co-solvents on the single-chain TNK (sc-TNK) in comparison to that on tc-TNK. Unlike single-chain tenecteplase, the two-chain form undergoes reversible denaturation which is somehow perturbed in some cases as the result of the presence of osmolytes. Very minor changes in the secondary structure and the tertiary structure were observed. The molecular dynamics simulations and comparative structural analysis of catalytic domain of the protein in the single-chain and two-chain forms in pure water, mannitol/water, trehalose/water, and sucrose/water showed that while the stabilizing effect of the three osmolytes on tc-TNK might be induced by preferential accumulation of these molecules around the nonpolar and aromatic residues, that is to say, fewer water-hydrophobic residues' interactions in tc-TNK, sc-TNK is stabilized by preferential exclusion effect.


Assuntos
Simulação de Dinâmica Molecular , Conformação Proteica , Tenecteplase/química , Animais , Ativação Enzimática , Peptídeos/química , Conformação Proteica/efeitos dos fármacos , Estabilidade Proteica , Análise Espectral , Termodinâmica
5.
Andrologia ; 51(2): e13189, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30474123

RESUMO

This study aimed to compare main molecular markers of hypoxia (HIF1-α and P53) and inflammation (TLR-2, TLR-4 and TNF-α) pathways between infertile men with varicocele and fertile individuals. Sperm parameters such as sperm concentration, motility and morphology were assessed according to World Health Organization (Laboratory manual for the examination and processing of human semen. Geneva, Switzerland, 2010) guideline in 20 infertile men with grade II or III varicocele, and 20 fertile men candidate of family balancing. In addition, sperm DNA fragmentation and molecular markers involved in hypoxia and inflammation pathways were evaluated by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay and real-time PCR respectively. Mean of sperm parameters (concentration, motility and morphology) and DNA integrity were significantly lower in infertile men with varicocele compared to fertile individuals. Unlike markers involved in inflammation pathway, mean expression of markers of hypoxia pathway (HIF1-α and P53) was significantly higher in infertile men with varicocele compared to fertile individuals (p < 0.05), and also a significant correlation was observed between expression of HIF1-α and P53 (r = 0.461; p = 0.003). Overall, the result of this study suggests higher likelihood of involvement of hypoxia pathway, in comparison with inflammation pathway, in pathogenesis varicocele associated with male infertility.


Assuntos
Hipóxia/metabolismo , Infertilidade Masculina/etiologia , Inflamação/metabolismo , Espermatozoides/metabolismo , Varicocele/complicações , Apoptose/fisiologia , Biomarcadores/metabolismo , Forma Celular/fisiologia , Fragmentação do DNA , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Infertilidade Masculina/metabolismo , Masculino , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/citologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Varicocele/metabolismo
6.
Andrologia ; 50(9): e13085, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30039556

RESUMO

Alpha-lipoic acid (ALA) is a disulphide compound with multifunctional antioxidant properties and is soluble in both water and lipid. Several recent studies evaluated efficacy of ALA in various diseases related to oxidative damage such as diabetes, multiple sclerosis and Alzheimer and concluded that ALA can reduce oxidative stress by quenching reactive oxygen and nitrogen species, restoring antioxidants such as glutathione, vitamins C and E, and/or improving activity of antioxidant enzymes. Varicocele, an enlargement of the veins in scrotum, is considered as the most common repairable cause of male infertility and is associated with high levels of oxidative stress. In this study, surgical varicocele was induced in 30 adult male Wistar rats with other 20 rats serving as sham-operated and nonoperated control. Varicocele caused significant worsening of sperm parameters, DNA damage and lipid peroxidation 2 and 4 months after surgery. A 2-month ALA administration after surgery was able to revert these effects. These results clearly showed that ALA can reduce the negative side effects of elevated testicular temperature and increased oxidative stress in varicocelised rats. This study warrants future clinical research to assess whether ALA is of help in the treatment of infertile men with varicocele.


Assuntos
Antioxidantes/uso terapêutico , Infertilidade Masculina/tratamento farmacológico , Espermatozoides/efeitos dos fármacos , Ácido Tióctico/uso terapêutico , Varicocele/complicações , Animais , Antioxidantes/farmacologia , Cromatina/efeitos dos fármacos , Suplementos Nutricionais , Avaliação Pré-Clínica de Medicamentos , Infertilidade Masculina/etiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos Wistar , Testículo/efeitos dos fármacos , Ácido Tióctico/farmacologia
7.
BJU Int ; 122(3): 480-489, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29752770

RESUMO

OBJECTIVES: To investigate whether micronutrients in support of the one-carbon cycle and glutathione synthesis are effective in improving sperm damage after surgical varicocoele induction in rats and whether any effect is achieved without a rebound reductive stress as seen with oral antioxidants. MATERIALS AND METHODS: Surgical varicocoele was induced in adult male Wistar rats and resulted in significant damage to the testis and sperm cells measured at 2 and 4 months after surgery. At 2 months after surgery, rats received a 2-month oral supplementation in support of the one-carbon cycle containing B vitamins (B2, B3, B6, folic acid and B12), N-acetyl-cysteine, zinc, small amounts of vitamin E, and a natural source of betalains and quercetine (Condensyl® ; Parthenogen SAGL, Lugano, Switzerland and Nurilia SARL, Lyon, France). RESULTS: One-carbon cycle supplementation, compared to untreated controls, significantly improved the morphometric characteristics of testis (P < 0.05), sperm concentration, motility and abnormal morphology (P < 0.001), sperm chromatin condensation (aniline blue staining, P < 0.05), sperm DNA damage (acridine orange staining, P < 0.05) and sperm lipid peroxidation (BODIPY C11, P < 0.001). The improvement in both nuclear condensation and DNA damage and the lack of excessive inhibition of lipid peroxidation confirmed that no reductive stress had occurred. CONCLUSIONS: Micronutrients in support of the one-carbon cycle are effective in the treatment of surgically induced varicocoele in rats, probably by activating natural antioxidant defences and epigenetics. These results support the idea that essential micronutrients including B vitamins may also have a positive influence in clinical varicocoele, which should be tested in prospective clinical trials.


Assuntos
Ciclo do Carbono/efeitos dos fármacos , Infertilidade Masculina/terapia , Micronutrientes/farmacologia , Espermatozoides/efeitos dos fármacos , Varicocele/complicações , Animais , Antioxidantes/farmacologia , Ciclo do Carbono/fisiologia , Suplementos Nutricionais , Infertilidade Masculina/etiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Análise do Sêmen/métodos , Espermatozoides/fisiologia , Testículo/fisiopatologia , Varicocele/terapia
8.
J Assist Reprod Genet ; 33(12): 1649-1655, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27612872

RESUMO

PURPOSE: We aimed to compare the expression of phospholipase C ζ (PLCζ), as one of the main sperm factors involved in oocyte activation, at both RNA and protein levels in fertile men and those with varicocele. METHODS: This study included 35 individuals with male factor infertility presenting primary infertility with grade II and III unilateral varicocele and 20 fertile men without varicocele. Semen parameters were assessed according to WHO 2010. Sperm DNA fragmentation, relative expression of PLCζ at messenger RNA, and protein levels were evaluated by sperm chromatin structure assay (SCSA), real-time PCR, and Western blot analysis, respectively. RESULTS: The results of this study reveal that the mean relative expression of PLCζ was significantly lower in individuals with varicocele compared to fertile men at both transcription and translation levels. In addition, the percentage of DNA fragmentation was significantly higher in infertile men with varicocele compared to fertile men. CONCLUSIONS: The findings of the present study illustrate that one of the etiologies of reduced fertility associated with varicocele is the low expression of PLCζ. This effect could subsequently reduce the sperm ability to induce oocyte activation. Therefore, these results hold promise to modify our understanding of reproductive physiology of varicocele state.


Assuntos
Infertilidade Masculina/genética , Fosfoinositídeo Fosfolipase C/biossíntese , Sêmen/metabolismo , Varicocele/genética , Fragmentação do DNA , Humanos , Infertilidade Masculina/patologia , Masculino , Oócitos/crescimento & desenvolvimento , Fosfoinositídeo Fosfolipase C/genética , Espermatozoides/patologia , Varicocele/patologia
9.
Nanomedicine ; 10(7): 1559-69, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24792217

RESUMO

Interactions between Schwann cells (SCs) and scaffolds are important for tissue development during nerve regeneration, because SCs physiologically assist in directing the growth of regenerating axons. In this study, we prepared electrospun scaffolds combining poly (3-hydroxybutyrate) (PHB) and poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) functionalized with either collagen I, H-Gly-Arg-Gly-Asp-Ser-OH (GRGDS), H-Tyr-Ile-Gly-Ser-Arg-NH2 (YIGSR), or H-Arg-Asn-Ile-Ala-Glu-Ile-Ile-Lys-Asp-Ile-OH (p20) neuromimetic peptides to mimic naturally occurring ECM motifs for nerve regeneration. Cells cultured on fibrous mats presenting these biomolecules showed a significant increase in metabolic activity and proliferation while exhibiting unidirectional orientation along the orientation of the fibers. Real-time PCR showed cells cultured on peptide-modified scaffolds had a significantly higher neurotrophin expression compared to those on untreated nanofibers. Our study suggests that biofunctionalized aligned PHB/PHBV nanofibrous scaffolds may elicit essential cues for SCs activity and could serve as a potential scaffold for nerve regeneration. From the clinical editor: Nanotechnology-based functionalized scaffolds represent one of the most promising approaches in peripheral nerve recovery, as well as spinal cord recovery. In this study, bio-functionalized and aligned PHB/PHBV nanofibrous scaffolds were found to elicit essential cues for Schwann cell activity, therefore could serve as a potential scaffold for nerve regeneration.


Assuntos
Nanofibras , Peptídeos/química , Poli-Hidroxialcanoatos/química , Células de Schwann/citologia , Alicerces Teciduais , Ensaio de Imunoadsorção Enzimática , Humanos , Microscopia Eletrônica de Varredura , Proibitinas , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Cell Reprogram ; 14(4): 295-304, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22862150

RESUMO

Despite widespread application of intracytoplasmic sperm injection (ICSI) in human-assisted reproductive techniques (ART), the efficiency of this method is still far from satisfactory in livestock, particularly in the bovine species with its unique sperm condensation. On the basis of the natural chemical structure of chromatin in condensed sperm, we developed a novel combined heparin-reduced glutathione (GSH) sperm pretreatment that improves the efficiency of bovine ICSI via selection of the most appropriate sperm at the time of ICSI. Assessment of sperm DNA integrity revealed that this pretreatment can be considered as a safe and efficient approach for in vitro sperm decondensation when compared to conventional sperm pretreatments with dithiothreitol (DTT). Injection of completely decondensed bull sperm derived from this pretreatment significantly improved fertilization and blastocyst formation rates compared to untreated or intact sperm injection (34.8 ± 2.7 and 29.1 ± 1.5 vs. 12.0 ± 3.2 and 15.9 ± 1.2%, respectively; p<0.05). Real-time PCR analysis revealed that expression of pluripotent and anti-apoptosis markers in blastocysts derived by injection of completely decondensed sperm from heparin-GSH pretreatment were comparable to IVF when compared to the DTT pretreatment and control ICSI groups (p<0.05). The results of this study suggested that the degree of sperm decondensation derived from heparin-GSH pretreatment may affect ICSI efficiency in bovine.


Assuntos
Anticoagulantes/farmacologia , Glutationa/farmacologia , Heparina/farmacologia , Injeções de Esperma Intracitoplásmicas/métodos , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Bovinos , Feminino , Humanos , Proteínas Inibidoras de Apoptose/biossíntese , Masculino , Espermatozoides/citologia , Espermatozoides/metabolismo
11.
Mol Reprod Dev ; 78(8): 576-84, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21721066

RESUMO

In this study, fibroblast cells were stably transfected with mouse POU5F1 promoter-driven enhanced green fluorescent protein (EGFP) to investigate the effect of S-adenosylhomocysteine (SAH), the reversible non-toxic inhibitor of DNA-methyltransferases (DNMTs), at different intervals post-fusion on in vitro development of cloned bovine embryos. Treatment with SAH for 12 hr resulted in 54.6 ± 7.7% blastocyst production, which was significantly greater than in vitro fertilized embryos (IVF: 37.2 ± 2.7%), cloned embryos treated with SAH for 72 hr (31.0 ± 7.6%), and control cloned embryos (34.6 ± 3.6%). The fluorescence intensities of the EGFP-POU5F1 reporter gene at all intervals of SAH treatment, except of 72 hr, were significantly higher than control somatic cell nuclear transfers (SCNT) embryos. The intensity of DNA-methylation in cloned embryos treated with SAH for 48 hr was similar to that of IVF embryos, and was significantly lower than the other SCNT groups. The levels of H3K9 acetylation in all SCNT groups were significantly lower than IVF embryos. Real-time PCR analysis of gene expression revealed significantly higher expression of POU5F1 in cloned versus IVF blastocysts. Neither embryo production method (SCNT vs. IVF) nor the SAH treatment interval affected expression of the BCL2 gene. Cloned embryos at all intervals of SAH treatment, except for 24 hr, had significantly increased VEGF transcript compared to IVF and control SCNT embryos. It was suggested that the time interval of DNMT inhibition may have important consequences on different in vitro features of bovine SCNT, and the improving effects of DNMT inhibition on developmental competency of cloned embryos are restricted to a specific period of time preceding de novo methylation.


Assuntos
Blastocisto/efeitos dos fármacos , Clonagem de Organismos/métodos , Embrião de Mamíferos/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , S-Adenosil-Homocisteína/farmacologia , Acetilação/efeitos dos fármacos , Animais , Blastocisto/metabolismo , Bovinos , Metilação de DNA/efeitos dos fármacos , Embrião de Mamíferos/fisiologia , Epigênese Genética , Feminino , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Histonas/metabolismo , Masculino , Camundongos , Microscopia de Fluorescência , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Transfecção
12.
Fertil Steril ; 89(4): 892-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17583699

RESUMO

OBJECTIVE: To evaluate the relationship between late spermiogenic events, including histone-protamine replacement, acrosome integrity, and sperm morphology, with fertilization rate after intracytoplasmic sperm injection (ICSI). DESIGN: Prospective study. SETTING: Isfahan Fertility and Infertility Center, Royan Institute, Tehran, Iran. PATIENT(S): Semen samples from 68 infertile couples undergoing ICSI at Isfahan Fertility and Infertility center were assessed during this study. INTERVENTION(S): Semen analysis was carried out according to World Health Organization criteria. Protamine deficiency, acrosin activity, sperm morphology, and acrosome size were assessed by chromomycin A3 (CMA3) staining, gelatinolysis test, and Papanicolaou staining (strict criteria), respectively. MAIN OUTCOME MEASURE(S): The correlation between protamine deficiency, sperm morphology, acrosin activity, and acrosome size with each other and fertilization rate were assessed. RESULT(S): Percentage CMA3 positivity and mean halo diameter show a significant correlation with fertilization rate. However, no correlation was found between sperm normal morphology and fertilization rate. The mean values of acrosome size and fertilization rate were significantly different when patients were grouped for CMA3 positivity of 40%. Multiple linear regression analysis revealed that only protamine deficiency has direct effect on fertilization rate. CONCLUSION(S): Protamine deficiency appears to have a more significant effect on fertilization after ICSI than acrosin activity and semen parameters.


Assuntos
Fertilização in vitro , Infertilidade Masculina/terapia , Sêmen , Injeções de Esperma Intracitoplásmicas , Espermatozoides , Acrosina/análise , Acrossomo/patologia , Adulto , Forma Celular , Feminino , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Estudos Prospectivos , Protaminas/análise , Sêmen/química , Sêmen/citologia , Espermatozoides/química , Espermatozoides/patologia , Falha de Tratamento
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