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1.
Biology (Basel) ; 13(4)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38666851

RESUMO

Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, great attention has been paid to the impact of chronic low-dose-rate (LDR) radiation exposure on biological systems. The reproductive system is sensitive to radiation, with implications connected to infertility. We investigated the testis ultrastructure of the wild large Japanese field mouse (Apodemus speciosus) from three areas contaminated after the FDNPP accident, with different levels of LDR radiation (0.29 µSv/h, 5.11 µSv/h, and 11.80 µSv/h). Results showed good preservation of the seminiferous tubules, comparable to the unexposed animals (controls), except for some ultrastructural modifications. Increases in the numerical density of lipid droplet clusters in spermatogenic cells were found at high levels of LDR radiation, indicating an antioxidant activity rising due to radiation recovery. In all groups, wide intercellular spaces were found between spermatogenic cells, and cytoplasmic vacuolization increased at intermediate and high levels and vacuolated mitochondria at the high-level. However, these findings were also related to the physiological dynamics of spermatogenesis. In conclusion, the testes of A. speciosus exposed to LDR radiation associated with the FDNPP accident showed a normal spermatogenesis, with some ultrastructural changes. These outcomes may add information on the reproductive potential of mammals chronically exposed to LDR radiation.

2.
Hematol Rep ; 16(1): 22-31, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38247993

RESUMO

Plasmacytoma is a neoplastic disorder originating from plasma cells, with bone and soft tissue being common sites of manifestation. This report presents the clinical and radiological findings of a 65-year-old female patient who presented with an exophytic lesion in the upper right lateral incisor region. The lesion appeared as a unilocular radiotransparent area in imaging tests. Following an excisional biopsy, histological and immunohistochemical evaluations confirmed the presence of mature plasmacellular elements and small infiltrates of B and T lymphocytes. The patient did not exhibit systemic manifestations of multiple myeloma. Surgical intervention, in the form of enucleation of the lesion combined with root canal treatment and apicoectomy, was performed. This case underscores the rare occurrence of plasmacytoma in the jaw region and highlights the importance of surgical management in cases where structural damage or functional impairment is present. Further research on novel treatment approaches is also mentioned, including targeted therapies, immunomodulatory agents, and monoclonal antibodies. The patient is currently under the care of a hematologist for further investigation and the choice of the most appropriate therapy.

3.
Cryobiology ; 110: 93-102, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36417967

RESUMO

Ovarian follicle depletion and premature ovarian failure are significant challenges in cancer patients subjected to radio- or chemotherapy. Ovarian tissue (OT) cryopreservation would be an option when other fertility preservation methods are not accessible. This study aimed to analyze the structure and ultrastructure of human OTs transplanted onto chick embryo chorioallantois membrane (CAM) after cryopreservation by vitrification or slow freezing. OTs from 10 cancer patients underwent cryopreservation. CAM transplantation was done on fresh and cryopreserved OTs, to assign samples to nine study groups as follows: 1) FI-FIII = fresh, 5- and 10-days post-CAM transplantation groups; 2) VI-VIII = vitrified, 5- and 10-days post-transplantation vitrified groups; 3) SFI-SFIII: slow frozen, 5- and 10-days post-transplantation slow freezing groups. Proliferation ability, folliculogenesis, and structural and ultrastructure were analyzed. The density of primordial follicles did not change after both freezing methods, but reduced after 5 (P ≥ 0.05) and 10 days (P ≤ 0.05) post-CAM transplantation. The follicular grade significantly decreased in all transplanted tissues (P ≤ 0.0). The proliferation marker increased after cryopreservation, but reduced after transplantation (P ≤ 0.05). TEM evaluation showed better follicular ultrastructure in the fresh group, after transplantation. Stromal ultrastructure appeared more preserved after vitrification compared with slow freezing. There was no sign of malignant cell contamination after transplantation. Some follicular TEM abnormalities were found in both methods of freezing, with a better transplantation rate after vitrification. Also, enhanced follicular activation resulted in faster follicular depletion in this method. The information regarding post grafting events would improve our knowledge for longer OTs' lifespans.


Assuntos
Neoplasias , Vitrificação , Feminino , Animais , Humanos , Embrião de Galinha , Congelamento , Criopreservação/métodos , Ovário , Folículo Ovariano
4.
Hum Mol Genet ; 31(15): 2535-2547, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35220430

RESUMO

Epidermal development and maintenance are finely regulated events requiring a strict balance between proliferation and differentiation. Alterations in these processes give rise to human disorders such as cancer or syndromes with skin and annexes defects, known as ectodermal dysplasias (EDs). Here, we studied the functional effects of two novel receptor-interacting protein kinase 4 (RIPK4) missense mutations identified in siblings with an autosomal recessive ED with cutaneous syndactyly, palmoplantar hyperkeratosis and orofacial synechiae. Clinical overlap with distinct EDs caused by mutations in transcription factors (i.e. p63 and interferon regulatory factor 6, IRF6) or nectin adhesion molecules was noticed. Impaired activity of the RIPK4 kinase resulted both in altered epithelial differentiation and defective cell adhesion. We showed that mutant RIPK4 resulted in loss of PVRL4/nectin-4 expression in patient epidermis and primary keratinocytes, and demonstrated that PVRL4 is transcriptionally regulated by IRF6, a RIPK4 phosphorylation target. In addition, defective RIPK4 altered desmosome morphology through modulation of plakophilin-1 and desmoplakin. In conclusion, this work implicates RIPK4 kinase function in the p63-IRF6 regulatory loop that controls the proliferation/differentiation switch and cell adhesion, with implications in ectodermal development and cancer.


Assuntos
Displasia Ectodérmica , Fatores Reguladores de Interferon , Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Displasia Ectodérmica/metabolismo , Homeostase , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Queratinócitos/metabolismo , Nectinas , Proteínas Serina-Treonina Quinases
5.
J Obstet Gynaecol Res ; 46(8): 1384-1392, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32500582

RESUMO

AIM: Scientists have tried to culture and transplant the ovarian tissues (OT), to preserve fertility in cancer patients. However, one of the main limitations to the applicability of this technique is the folliculogenesis disruption after transplantation. Due to the roles exerted by growth differentiation factor-9ß (GDF9ß), we decided to determine the most effective dose of GDF9ß on promotion of folliculogenesis and angiogenesis in sheep OT grafted onto the chick chorioallantoic membrane (CAM). METHODS: Fresh sheep OT were grafted onto the CAM for 5 days, and divided into four groups based on the addition of increasing doses of GDF9ß (0, 150, 200 and 250 ng/mL). Following culture, histological (hematoxylin and eosin [H&E] staining) and immunohistological studies (Ki-67) were done. Fibrotic and necrotic regions were measured using MICROVISIBLE software. For comparing the follicle development rates between the groups as well as differences in the Ki-67-positive follicles, analysis of variance was applied. RESULTS: In both 200 and 250 ng/mL GDF9ß groups, significantly higher rates of intermediary and primary follicles were observed, also the numbers of good quality follicles increased in the aforementioned groups and the rates of fibrotic and necrotic areas decreased. Moreover, in the 200 and 250 ng/mL GDF9ß groups, the number of capillaries and the proliferative activity increased. The lower dose of GDF9ß (150 ng/mL) neither activated the primordial follicles nor lead to an increase in the number of growing follicles. CONCLUSION: Addition of high dosages of GDF9ß to the OT, grafted onto the CAM resulted in higher folliculogenesis and better transplantation features due to improvement in angiogenesis.


Assuntos
Membrana Corioalantoide , Folículo Ovariano , Animais , Embrião de Galinha , Feminino , Fatores de Diferenciação de Crescimento , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Ovinos
6.
J Reprod Dev ; 66(4): 387-397, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32350229

RESUMO

Controlled ovarian hyperstimulation (COH) is routinary used in assisted reproductive technologies (ARTs) to increase the yields of mature oocytes. The possibility that patients with a history of failures or poor-responders may develop side-effects following these treatments is still debated. Epidemiological studies reported controversial results about pregnancy outcome and the risk of developing gynecological cancers. By using a mouse model, here we compared the ultrastructural features of fallopian tubes (FTs) obtained from mice undergoing or not (control, CTR) four (4R) and eight (8R) rounds of gonadotropin stimulation. Although the morphological characteristics of oviductal layers seemed unaffected by repeated treatments, dose-response ultrastructural alterations in the ampulla appeared in the 4R group and even more in the 8R group. The targets were oviductal ciliated (CCs) and non-ciliated (NCCs) cells, which showed damaged mitochondria and glycogen accumulations in the cytoplasm. The drastic reduction of CCs, evident after 4R, was supported by the absence of cilia. After 8R, glycogen granules were significantly reduced and massive degeneration of mitochondria, which appeared swollen and/or vacuolated, occurred in NCCs. Moreover, disintegrated mitochondria were found at the periphery of mitophagic vacuoles with evident signs of cristolysis. The morphometric analysis evidenced a significant increase in the density and frequency of damaged mitochondria after 4R and 8R. The absence of cilia, necessary to sustain oviductal transport of oocytes, spermatozoa and embryos, may originate from either mitochondrial dysfunction or glycogen consumption. These results suggest that repeated COH treatments could induce alterations impairing fertilization and embryo transport toward the uterus.


Assuntos
Cílios/ultraestrutura , Epitélio/ultraestrutura , Tubas Uterinas/ultraestrutura , Indução da Ovulação , Animais , Feminino , Camundongos , Mitocôndrias/ultraestrutura , Mitofagia/fisiologia , Vacúolos/ultraestrutura
7.
Int. j. morphol ; 38(1): 96-100, Feb. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1056404

RESUMO

During aging, usually graying of the hair occurs as a result of oxidative stress. Driven by social acceptance and self-perception of the exterior appearance, both men and women rely on hair dyeing products, in order to mask the graying hair. At the same time, a frequent use of synthetic products and treatment can damage the hair shaft; for this reason, this study aimed to evaluate the morphological effect of the herbal dye derived from Lawsonia inermis (henna), on hair. Dyed hairs were evaluated by means of SEM. Subsequently, they were compared, qualitatively and quantitatively, with undyed hairs. Results showed a positive impact on the cuticula pattern and on the diameters of the examined samples, after henna application. Different results, about the degree and the type of morphological changes occurring on pigmented hairs, may depend on the phenotype and on the health condition of hair, before dye treatment.


Durante el envejecimiento, generalmente se produce el envejecimiento del cabello como resultado del estrés oxidativo. Motivados por la aceptación social y la autopercepción de la apariencia, tanto hombres como mujeres confían en productos para teñir el cabello para enmascarar las canas. Al mismo tiempo, el uso frecuente de productos y tratamientos sintéticos puede dañar el tallo del cabello. Por esta razón, este estudio tuvo como objetivo evaluar el efecto morfológico del tinte derivado de Lawsonia inermis (henna) en el cabello. Los cabellos teñidos se evaluaron mediante SEM. Posteriormente, se compararon, cualitativa y cuantitativamente, con cabellos sin teñir. Los resultados mostraron un impacto positivo en el patrón de la cutícula y en los diámetros de las muestras examinadas, después de la aplicación de henna. Los diferentes resultados, sobre el grado y el tipo de cambios morfológicos que ocurren en los cabellos pigmentados, pueden depender del fenotipo y del estado de salud del cabello, antes del tratamiento con tinte.


Assuntos
Humanos , Microscopia Eletrônica de Varredura , Folículo Piloso/efeitos dos fármacos , Lawsonia (Planta) , Tinturas para Cabelo/farmacologia , Folículo Piloso/ultraestrutura , Cabelo/efeitos dos fármacos , Cabelo/ultraestrutura
8.
Mol Reprod Dev ; 87(1): 91-101, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31749232

RESUMO

Formation and subsequent break down of ovarian germ cell (GC) cysts is a key and an evolutionary-conserved developmental event, described in phylogenetically diverse species of invertebrates and vertebrates. In mammals, cyst break down (CBD) ends at the time of, or soon after, birth with the formation of primordial follicles enclosing single oocytes, which constitute the sole reservoir of gametes available through the whole female's reproductive life. In this study, we challenge this paradigm demonstrating the constitutive presence of a large number of cysts, enclosing two-thirty GCs, in the ovary of the adult armadillo Chaetophractus villosus, belonging to the superorder Xenarthra, one of the earliest offshoots among placentals. We also describe that (a) GCs enclosed within cysts are connected by intercellular bridges-intercellular bridges-markers of their clonal origin; (b) CBD occurs through four main phases, ending with primordial follicles containing single oocytes; (c) GCs encompass meiotic prophase I stages, from leptotene to diplotene; (d) seasonal variations in the number of GCs enclosed within cysts, suggesting the presence of a GC multiplying activity. The armadillo C. villosus''s ovary emerges as an extraordinary resource to investigate folliculogenesis and to explore the evolutionary past of the mammalian ovary.


Assuntos
Tatus/crescimento & desenvolvimento , Prófase Meiótica I/fisiologia , Oócitos/citologia , Oogênese/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Animais , Feminino , Folículo Ovariano/citologia , Estações do Ano
9.
Hum Reprod ; 34(4): 601-611, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30865267

RESUMO

STUDY QUESTION: Does the oxygen concentration in the culture medium [either physiologic (5%) or atmospheric (20%)] affect mitochondrial ultrastructure and function in preimplantation mouse embryos generated by IVF? SUMMARY ANSWER: Embryos cultured in 20% oxygen show increased mitochondrial abnormalities compared to embryos cultured in 5% oxygen. WHAT IS KNOWN ALREADY: ART are widely used and have resulted in the birth of more than 8 million children. A variety of media and oxygen concentrations are used to culture embryos. Embryos cultured under physiological O2 tension (5%) reach the blastocyst stage faster and have fewer alterations in gene expression when compared with embryos cultured under atmospheric oxygen conditions (20%). The mechanisms by which oxygen tension affects preimplantation development remain unclear, but mitochondria are believed to play an important role. The aim of this study was to evaluate how mitochondrial ultrastructure and function in IVF embryos were affected by culture under physiologic (5%) or atmospheric (20%) oxygen concentrations. STUDY DESIGN, SIZE, DURATION: Zygotes, 2-cell, 4-cell, morula and blastocyst were flushed out of the uterus after natural fertilization and used as controls. IVF was performed in CF1 x B6D2F1 mice and embryos were cultured in Potassium simplex optimized medium (KSOM) with amino acids (KAA) under 5% and 20% O2 until the blastocyst stage. Embryo development with the addition of antioxidants was also tested. PARTICIPANTS/MATERIALS, SETTING, METHODS: Mitochondrial function was assessed by measuring mitochondrial membrane potential, reactive oxygen species (ROS) production, ATP levels, and the expression of selected genes involved in mitochondrial function. Mitochondria ultrastructure was evaluated by transmission electron microscopy (TEM). MAIN RESULTS AND THE ROLE OF CHANCE: Embryos cultured under 20% O2 had fewer mitochondria and more vacuoles and hooded (abnormal) mitochondria compared to the other groups (P < 0.05). At the blastocyst stage the mitochondria of IVF embryos cultured in 20% O2 had lower mtDNA copy number, a denser matrix and more lamellar cristae than controls. Overall IVF-generated blastocysts had lower mitochondrial membrane potential, higher ROS levels, together with changes in the expression of selected mitochondrial genes (P < 0.05). ATP levels were significantly lower than controls only under 5% O2, with the 20% O2 IVF group having intermediate levels. Unexpectedly, adding antioxidant to the culture medium did not improve development. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Findings in mice embryos might be different from human embryos. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that changes in the mitochondria may be part of the mechanism by which lower oxygen concentration leads to better embryo development and further emphasize the importance of mitochondria as a locus of reprogramming. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by R01 HD 082039 to PFR, the Department of Life, Health and Environmental Sciences, University of L'Aquila, Italy (RIA 2016-2018) and the Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, La Sapienza University of Rome, Italy (University grants 2016-2017). The authors declare no competing interests.


Assuntos
Blastocisto/metabolismo , Técnicas de Cultura Embrionária/métodos , Fertilização in vitro/métodos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Oxigênio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Meios de Cultura/química , DNA Mitocondrial/genética , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Masculino , Potencial da Membrana Mitocondrial , Camundongos , Microscopia Eletrônica de Transmissão , Mitocôndrias/genética , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma , Vacúolos/metabolismo
10.
Cancer Biol Ther ; 19(8): 722-734, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29580188

RESUMO

It has become clear that non-tumor cells in the microenvironment, especially fibroblasts, actively participate in tumor progression. Fibroblasts conditioned by tumor cells become "activated" and, as such, are identified as CAFs (cancer-associated fibroblasts). These CAFs remodel the tumor stroma to make it more favourable for cancer progression. The aim of this work was to verify whether EVs (extracellular vesicles - whose role as mediators of information between tumor and stromal cells is well known) released from human ovarian cancer cells were able to activate fibroblasts. EVs isolated from SKOV3 (more aggressive) and CABA I (less aggressive) cells were administered to fibroblasts. The consequent activation was supported by morphological and molecular changes in treated fibroblasts; XTT assays, zymographies, wound healing tests and invasion assays also highlighted higher proliferation, motility, invasiveness and enzyme expression. The secretome of these "activated" fibroblasts was, in turn, able to modulate the responses (proliferation, motility and invasion) of fibroblasts, and of tumor and endothelial cells. These findings support the idea that ovarian cancer cells can modulate fibroblast behaviour through the release of EVs, activating them to a CAFs-like state; the latter are able, in turn, to stimulate the surrounding cells. EVs from SKOV3 rather than from CABA I seem to be more efficient in some processes.


Assuntos
Vesículas Extracelulares/metabolismo , Fibroblastos/metabolismo , Neoplasias Ovarianas/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Células Endoteliais/metabolismo , Vesículas Extracelulares/ultraestrutura , Feminino , Humanos , Neoplasias Ovarianas/patologia , Microambiente Tumoral
11.
J Reprod Dev ; 64(1): 75-82, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29225323

RESUMO

Mancozeb, an ethylene bis-dithiocarbamate, is widely used as a fungicide and exerts reproductive toxicity in vivo and in vitro in mouse oocytes by altering spindle morphology and impairing the ability to fertilize. Mancozeb also induces a premalignant status in mouse granulosa cells (GCs) cultured in vitro, as indicated by decreased p53 expression and tenuous oxidative stress. However, the presence and extent of ultrastructural alterations induced by mancozeb on GCs in vitro have not yet been reported. Using an in vitro model of reproductive toxicity, comprising parietal GCs from mouse antral follicles cultured with increasing concentrations of mancozeb (0.001-1 µg/ml), we sought to ascertain the in vitro ultrastructural cell toxicity by means of transmission (TEM) and scanning (SEM) electron microscopy. The results showed a dose-dependent toxicity of mancozeb on mouse GCs. Ultrastructural data showed intercellular contact alterations, nuclear membrane irregularities, and chromatin marginalization at lower concentrations, and showed chromatin condensation, membrane blebbing, and cytoplasmic vacuolization at higher concentrations. Morphometric analysis evidenced a reduction of mitochondrial length in GCs exposed to mancozeb 0.01-1 µg/ml and a dose-dependent increase of vacuole dimension. In conclusion, mancozeb induced dose-dependent toxicity against GCs in vitro, including ultrastructural signs of cell degeneration compatible with apoptosis, likely due to the toxic breakdown product ethylenethiourea. These alterations may represent a major cause of reduced/delayed/missed oocyte maturation in cases of infertility associated with exposure to pesticides.


Assuntos
Fungicidas Industriais/farmacologia , Células da Granulosa/efeitos dos fármacos , Maneb/farmacologia , Zineb/farmacologia , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Células da Granulosa/metabolismo , Células da Granulosa/ultraestrutura , Camundongos , Estresse Oxidativo/efeitos dos fármacos
12.
Reprod Biol ; 17(4): 349-356, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29030126

RESUMO

Lindane, which is one of the most persistent organochlorine pesticide contaminating the Aral Sea region, is associated with numerous pathologies of the female reproductive system, including infertility, due to its gap junction blocker activity. By using an in vitro model of reproductive toxicity consisting of mouse parietal granulosa cells (GCs) exposed to increasing concentrations of Lindane ranging from 1 to 100µM (L1; L10; L100), we aimed to ascertain the Lindane toxicity by evaluating the ultrastructure and expression of the cell death protein p53. GCs exposed to L1 showed an early sign of degeneration as chromatin marginalization and initial reduction of cell-to-cell contacts. Such effects increased at L10 with nuclear membrane invagination, cytoplasmic blebbing, reduction of microvilli and intercellular connections. L100 induced evident cellular damages with an extensive presence of vacuoles, cytoplasmic fragments, nuclear membrane vesiculation and abundant cellular debris. A dose-dependent increase of p53 expression was evident in the L1 and L10 groups but not in L100. These data provide evidence for a dose-dependent reproductive toxicity of the gap junction blocker Lindane, as seen in mouse GCs cultured in vitro by ultrastructural damage compatible with apoptosis. Since gap junctions may play a critical role in FSH-stimulated progesterone production, the ultrastructural damage here evidenced could explain the increase in the prevalence of reproductive pathologies and infertility in exposed women. Finally, this study provided a useful and repeatable model of reproductive toxicity in vitro, which is applicable to evaluate the detrimental effects of toxicants or the reversing effect of protective substances.


Assuntos
Morte Celular/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Hexaclorocicloexano/toxicidade , Inseticidas/toxicidade , Animais , Células Cultivadas , Feminino , Células da Granulosa/metabolismo , Células da Granulosa/ultraestrutura , Camundongos , Microscopia Eletrônica de Transmissão , Proteína Supressora de Tumor p53/metabolismo
13.
J Assist Reprod Genet ; 34(11): 1413-1426, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28822010

RESUMO

The use of immature oocytes subjected to in vitro maturation (IVM) opens interesting perspectives for fertility preservation where ovarian reserves are damaged by pathologies or therapies, as in PCO/PCOS and cancer patients. Human oocyte cryopreservation may offer some advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation and postponing childbirth. It also eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In addition, a successful oocyte cryopreservation program could eliminate the need for donor and recipient menstrual cycle synchronization. Recent advances in vitrification technology have markedly improved the oocyte survival rate after warming, with fertilization and implantation rates comparable with those of fresh oocytes. Healthy live births can be achieved from the combination of IVM and vitrification, even if vitrification of in vivo matured oocytes is still more effective. Recently, attention is given to highlight whether vitrification procedures are more successful when performed before or after IVM, on immature GV-stage oocytes, or on in vitro matured MII-stage oocytes. In this review, we emphasize that, even if there are no differences in survival rates between oocytes vitrified prior to or post-IVM, reduced maturation rates of immature oocytes vitrified prior to IVM can be, at least in part, explained by underlying ultrastructural and biomolecular alterations.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , Oogênese/genética , Vitrificação , Feminino , Humanos , Nascido Vivo , Oócitos/ultraestrutura , Gravidez
14.
Toxicol In Vitro ; 30(1 Pt B): 438-45, 2015 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-26407525

RESUMO

BACKGROUND: Mancozeb (MZ) is a fungicide that belongs to the subclass of metal (Mn/Zn) ethylene-bis-dithiocarbamate pesticides. In mouse and human granulosa cells (GCs) exposed to MZ (0.01 µg/ml), morphological modifications and significant alterations of p53 expression level in comparison with control GCs were recorded. OBJECTIVES: To investigate if MZ (0.01 µg/ml) induces oxidative stress and alters energy metabolism in exposed mouse GCs. RESULTS: Following fungicide exposure, GCs showed low p53 content, a depolarized mitochondrial membrane potential (ΔΨm), as well as low ATP and reduced glutathione (GSH) levels associated with increased reactive oxygen species (ROS) generation. No remarkable differences on other parameters such as ATP/ADP ratio, energy charge, as well as induction of apoptosis and DNA damage were found. The activation of AKT and PDK1 kinases in MZ-treated cells was observed. Inhibition of ROS generation by the antioxidant N-acetylcysteine (NAC) restored a normal expression level of p53. CONCLUSIONS: Our results demonstrate that the low dose of MZ here used induces a mild oxidative stress in GCs, and provides evidence for the possible involvement of AKT/PKB signaling pathway in triggering adaptive and survival response.


Assuntos
Trifosfato de Adenosina/biossíntese , Fungicidas Industriais/toxicidade , Células da Granulosa/efeitos dos fármacos , Maneb/toxicidade , Zineb/toxicidade , Animais , Células Cultivadas , Dano ao DNA , Feminino , Glutationa/metabolismo , Células da Granulosa/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteína Supressora de Tumor p53/análise
15.
PLoS One ; 10(4): e0124911, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25893245

RESUMO

Our aim is to verify if oocyte developmental potential is related to the timing of meiotic progression and to mitochondrial distribution and activity using prepubertal and adult oocytes as models of low and high developmental capacity respectively. Prepubertal and adult oocytes were incorporated in an in vitro maturation system to determine meiotic and developmental competence and to assess at different time points kinetic of meiotic maturation, 2D protein electrophoresis patterns, ATP content and mitochondria distribution. Maturation and fertilization rates did not differ between prepubertal and adult oocytes (95.1% vs 96.7% and 66.73% vs 70.62% respectively for prepubertal and adult oocytes). Compared to adults, prepubertal oocytes showed higher parthenogenesis (17.38% vs 2.08% respectively in prepubertals and adults; P<0.01) and polispermy (14.30% vs 2.21% respectively in prepubertals and adults; P<0.01), lower cleavage rates (60.00% vs 67.08% respectively in prepubertals and adults; P<0.05) and blastocyst output (11.94% vs 34.% respectively in prepubertals and adults; P<0.01). Prepubertal oocytes reached MI stage 1 hr later than adults and this delay grows as the first meiotic division proceeds. Simultaneously, the protein pattern was altered since in prepubertal oocytes it fluctuates, dropping and rising to levels similar to adults only at 24 hrs. In prepubertal oocytes ATP rise is delayed and did not reach levels comparable to adult ones. CLSM observations revealed that at MII, in the majority of prepubertal oocytes, the active mitochondria are homogenously distributed, while in adults they are aggregated in big clusters. Our work demonstrates that mitochondria and their functional aggregation during maturation play an active role to provide energy in terms of ATP. The oocyte ATP content determines the timing of the meiotic cycle and the acquisition of developmental competence. Taken together our data suggest that oocytes with low developmental competence have a slowed down energetic metabolism which delays later development.


Assuntos
Envelhecimento , Meiose/fisiologia , Mitocôndrias/metabolismo , Oócitos/citologia , Trifosfato de Adenosina/química , Animais , Blastocisto , Eletroforese em Gel Bidimensional , Feminino , Microscopia Eletrônica de Transmissão , Oócitos/crescimento & desenvolvimento , Ovário/metabolismo , Partenogênese/fisiologia , Maturidade Sexual , Ovinos , Carneiro Doméstico
16.
Reprod Biol Endocrinol ; 12: 115, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25421574

RESUMO

BACKGROUND: In vitro maturation (IVM) of immature oocytes retrieved from unstimulated ovaries may avoid side effects connected to hyperstimulation during IVF procedures, including the risk of cancer recurrence. In humans, the scarce availability of immature oocytes limits morphological studies. The monovular ovine may represent an experimental model for IVM studies. METHODS: To assess if the scarce developmental competence of prepubertal oocytes (PO) is related to morphological changes we analyzed, by light and transmission electron microscopy, cumulus-oocyte-complexes (COCs) from lambs (30-40 days old) and sheep (4-6 years old) at sampling and after 7 h, 19 h, 24 h of IVM. Meiotic progression was determined at the same time points. RESULTS: At sampling, the germinal vesicle (GV) of PO was round and centrally or slightly eccentrically located, whereas in adult oocytes (AO) it was irregularly shaped and flattened against the oolemma. PO, differently from AO, showed numerous trans-zonal projections. Organelles, including cortical granules (CGs), were more abundant in AO. After 7 h, the percentage of AO that underwent GVBD-MI transition increased significantly. In PO, the oolemma was juxtaposed to the ZP; in AO, it showed several spikes in correspondence of cumulus cells (CC) endings. In PO, organelles and isolated CGs were scattered in the ooplasm. In AO, groups of CGs were also present under the oolemma. After 19 h, PO underwent GVBD-MI transition; their oolemma showed several spikes, with CC projections retracted and detached from the ZP. AO underwent MI-MII transition; their oolemma regained a round shape. CGs were located beneath the plasmalemma, arranged in multiple, continuous layers, sometime discontinuous in PO. After 24 h, both groups reached the MII-stage, characterized by a regular oolemma and by expanded CCs. PO showed CGs distributed discontinuously beneath the oolemma, while AO showed a continuous monolayer of CGs. CONCLUSIONS: Even if PO were able of reaching morphological maturation after 24 h of IVM, our ultrastructural analysis allowed detecting the presumptive sequence of cytoplasmic alterations connected with the delay of nuclear maturation, that might explain the reduced developmental competence of such oocytes. Data from the sheep model are of interest for zootechny, and provide an experimental basis for improving human IVM technology.


Assuntos
Modelos Biológicos , Oócitos/crescimento & desenvolvimento , Oogênese , Desenvolvimento Sexual , Matadouros , Fatores Etários , Animais , Animais Endogâmicos , Polaridade Celular , Forma Celular , Células do Cúmulo/fisiologia , Células do Cúmulo/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Feminino , Técnicas de Maturação in Vitro de Oócitos , Itália , Meiose , Microscopia Eletrônica de Transmissão , Oócitos/citologia , Oócitos/ultraestrutura , Ovário/citologia , Ovário/crescimento & desenvolvimento , Ovário/ultraestrutura , Carneiro Doméstico , Fatores de Tempo
17.
Curr Pharm Des ; 20(34): 5388-97, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24502597

RESUMO

Unlike men, who have continuous spermatogenesis throughout most of their lifetime, women are born with a fixed supply of follicles, and this number progressively declines with age until the menopause. Beside age, the speed of follicle depletion can be regulated by genetic, hormonal and environmental influences. In the course of their lives, women are exposed to multiple chemicals and radiation sources that can increase the chance of developing permanent infertility and premature ovarian failure (POF). A wealth of experimental data indicate that iatrogenic (chemotherapy, radiotherapy) and xenobiotic agents (e.g., chemicals, pharmaceuticals) are potent ovotoxicants capable of accelerating ovarian reserve depletion. In the present review we reported the negative effects exerted on mammalian ovary by some widely diffused environmental chemicals, as polycyclic aromatic hydrocarbons (PAHs) and dithiocarbamate mancozeb, and by 1-3 butadiene and 4-vinylcycloexene, two occupational chemicals known to be capable of inducing ovarian cancer and infertility. Furthermore, attention has been devoted to the consequences of chemo- and radiotherapy on the ovary, both known to affect reproductive lifespan. Our increasing understanding of metabolic alterations induced by these agents is fundamental to individuate new therapeutic strategies aimed to prevent ovarian dysfunction in fertile women.


Assuntos
Antineoplásicos/efeitos adversos , Carcinógenos Ambientais/efeitos adversos , Exposição Ambiental/efeitos adversos , Ovário/efeitos dos fármacos , Animais , Antineoplásicos/toxicidade , Carcinógenos Ambientais/toxicidade , Feminino , Humanos , Doenças Ovarianas/induzido quimicamente , Doenças Ovarianas/metabolismo , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Ovário/metabolismo , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/metabolismo , Xenobióticos/efeitos adversos , Xenobióticos/toxicidade
18.
Reprod Fertil Dev ; 26(4): 562-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23622715

RESUMO

The aim of this study has been to determine the effects of in vivo post-ovulatory ageing (POA) on the distribution of spindle-associated proteins, histone H3/H4 post-translational modifications and on v-akt murine thymoma viral oncogene homolog 1 (Akt) expression levels. To this end, oocytes were retrieved 13, 29 and 33h after human chorionic gonadotrophin (hCG) treatment. The presence and distribution at the meiotic spindle of acetylated tubulin, γ-tubulin, polo kinase-1 and Ser473/Thr308 phosphorylated Akt (pAkt) as well as histone H3 and H4 acetylation and phosphorylation levels were assayed via immunofluorescence. Akt expression levels were determined via reverse transcription-polymerase chain reaction and western blotting analyses. Spindles from oocytes recovered 13h and 29h after hCG treatment showed similar levels of acetylated tubulin but ageing induced: (1) translocation of γ-tubulin from spindle poles to microtubules, (2) absence of Thr308- and Ser473-pAkt in 76% and 30% of oocytes, respectively, and (3) a significant reduction in phosphorylation levels of serine 10 on histone 3. At 29h, a significant decrease in Akt mRNA, but not in pAkt or Akt protein levels, was recorded. By contrast, protein content significantly decreased 33h after hCG. We conclude that POA impairs oocyte viability and fertilisability by altering the expression levels and spindle distribution of proteins that are implicated in cell survival and chromosome segregation. Together, these events could play a role in oocyte apoptosis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Senescência Celular , Oócitos/enzimologia , Ovulação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fuso Acromático/enzimologia , Acetilação , Animais , Sobrevivência Celular , Gonadotropina Coriônica/farmacologia , Regulação para Baixo , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Fertilização , Histonas/metabolismo , Camundongos , Oócitos/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/metabolismo , Fuso Acromático/efeitos dos fármacos , Fatores de Tempo , Tubulina (Proteína)/metabolismo , Quinase 1 Polo-Like
19.
Theriogenology ; 79(1): 116-26, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23122683

RESUMO

Thyroxine (T4) plus gonadotropins might stimulate ovarian follicular angiogenesis in immature infertile hypothyroid rdw rats by upregulating mRNA expression of major angiogenic factors. Development of growing corpus luteum (CL) is strongly related to angiogenesis and to morphofunctional development of microcirculation. Our aim was to investigate if T4 is involved in CL angiogenesis and in the activation of capillary cells and angiogenic factors after ovulation in a spontaneous model of hypothyroidism, the rdw rat. Rdw rats were treated with T4 plus gonadotropins (equine chorionic gonadotropin plus human chorionic gonadotropin; eCG+hCG) or gonadotropins alone in order to evaluate the effects of T4 on early luteal angiogenesis, on microvascular cells and on expression of major growth factors which are involved in the regulation of angiogenesis. Wistar-Imamichi rats treated with gonadotropins were used as controls. The ovaries were collected 4 days after hCG administration and analyzed using morphologic and molecular approaches. Thyroxine plus gonadotropins stimulated the growth of CLs and follicles as in controls, differently from rdw rats treated only with gonadotropins, in which CLs were not found and only small follicles, often atretic, could be recognized. In T4 plus gonadotropin-treated rdw rats CLs showed increased microvasculature, numerous activated capillaries characterized by sprouting and other angiogenic figures, and associated pericytes. Quantitative analysis revealed that the number of pericytes in T4 plus gonadotropin-treated rdw rats was comparable with that found in control rats and was significantly higher than that found in gonadotropin-treated rdw rats. The mRNA expression of vascular endothelial growth factor and basic fibroblast growth factor was significantly higher in control rats and in T4 plus gonadotropin-treated rdw rats than in gonadotropin-treated rdw rats. mRNA expression of tumor necrosis factor α, transforming growth factor ß, and epidermal growth factor did not show significant changes. Our data originally demonstrated that T4 promoted the growth of an active microcirculation in developing CLs of gonadotropin-primed hypothyroid rdw rats, mainly by inducing sprouting angiogenesis, pericyte recruitment, and upregulation of mRNA expression of vascular endothelial growth factor and basic fibroblast growth factor. In conclusion, we suggest that T4 plays a key role in restoring luteal angiogenesis in ovaries of immature hypothyroid rdw rats.


Assuntos
Corpo Lúteo/irrigação sanguínea , Corpo Lúteo/efeitos dos fármacos , Hipotireoidismo/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Tiroxina/farmacologia , Proteínas Angiogênicas/genética , Proteínas Angiogênicas/metabolismo , Animais , Contagem de Células , Corpo Lúteo/patologia , Corpo Lúteo/ultraestrutura , Feminino , Gonadotropinas/farmacologia , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/genética , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Pericitos/efeitos dos fármacos , Pericitos/patologia , Pericitos/ultraestrutura , Ratos , Ratos Mutantes , Ratos Wistar , Recuperação de Função Fisiológica/efeitos dos fármacos , Maturidade Sexual/genética , Maturidade Sexual/fisiologia , Tiroxina/uso terapêutico
20.
Iran J Reprod Med ; 11(1): 1-10, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24639686

RESUMO

 The use of ovarian stimulation for infertility treatment is associated with side effects of ovarian hyperstimulation syndrome (OHSS) and potential cancer risk. This is also true in high risk women such as those polycystic with ovary (PCO) and polycystic ovarian syndrome (PCOS). In vitro maturation (IVM) of oocytes was primarily developed to make IVF safe for women with PCO and at high risk of OHSS. The application of IVM of oocytes to assist clinical infertility treatment remains poor because of the reduced developmental competence of oocytes after IVM, despite several decades of research. Reduced meiotic maturation and fertilization rates, as well as low blastocyst production reveal short-term developmental insufficiency of oocytes when compared with in vivo-matured counterparts. In this review, the structural role of human oocytes, revealed by different technical approaches, to the success of IVM technology is highlighted.

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