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1.
Res Vet Sci ; 173: 105257, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636324

RESUMO

Decellularization is an innovative method to create natural scaffolds by removing all cellular materials while preserving the composition and three-dimensional ultrastructure of the extracellular matrix (ECM). The obtention of decellularized reproductive organs in cats might facilitate the development of assisted reproductive techniques not only in this species but also in other felids. The aim was to compare the efficiency of three decellularization protocols on reproductive organs (ovary, oviduct, and uterine horn) in domestic cats. The decellularization protocol involved 0.1% sodium dodecyl sulfate and 1%Triton X-100. Protocol 1 (P1) entailed 2-cycles of decellularization using these detergents. Protocol 2 (P2) was like P1 but included 3-cycles. Protocol 3 (P3) was similar to P2, with the addition of deoxyribonuclease incubation. Reproductive organs from nine cats were separated into two sides. One side served as the control (non-decellularized organ) while the contralateral side was the treated group (decellularized organ). The treated organs were subdivided into 3 groups (n = 3 per group) for each protocol. Both control and treated samples were analyzed for DNA content, histology (nuclear and ECM (collagen, elastin, and glycosaminoglycans (GAGs)) density), ultrastructure by electron microscopy, and cytotoxicity. The results of the study showed that P3 was the only protocol that displayed no nucleus residue and significantly reduced DNA content in decellularized samples (in all the studied organs) compared to the control (P < 0.05). The ECM content in the ovaries remained similar across all protocols compared with controls (P > 0.05). However, elastic fibers and GAGs decreased in decellularized oviducts (P < 0.05), while collagen levels remained unchanged (P > 0.05). Regarding the uterus, the ECM content decreased in decellularized uterine horns from P3 (P < 0.05). Electron microscopy revealed that the microarchitecture of the decellularized samples was maintained compared to controls. The decellularized tissues, upon being washed for 24 h, showed cytocompatibility following co-incubation with sperm. In conclusion, when comparing different decellularization methods, P3 proved to be the most efficient in removing nuclear material from reproductive organs compared to P1 and P2. P3 demonstrated its success in decellularizing ovarian samples by significantly decreasing DNA content while maintaining ECM components and tissue microarchitecture. However, P3 was less effective in maintaining ECM contents in decellularized oviducts and uterine horns.


Assuntos
Matriz Extracelular , Útero , Animais , Feminino , Gatos , Útero/citologia , Ovário/citologia , Ovário/ultraestrutura , Oviductos/citologia , Oviductos/ultraestrutura , DNA/análise , Octoxinol , Dodecilsulfato de Sódio , Glicosaminoglicanos/análise , Matriz Extracelular Descelularizada/química
2.
Zoology (Jena) ; 160: 126109, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37586295

RESUMO

Ovaries in earthworms belonging to the family Megascolecidae are paired structures attached to the septum in the anterior part of the XIII segment. They are fan to rosette shaped with numerous rows of growing oocytes, known as egg strings, radiating from the ovary center towards the segmental cavity. The histological and ultrastructural ovary organization in megascolecids and the course of oogenesis remain unknown. The paper presents the results of light and electron microscopy analyses of ovaries in six megascolecid species, three from the genus Amynthas and three from Metaphire. Both parthenogenetic and sexually reproducing species were included in the study. The organization and ultrastructure of ovaries in all studied species are broadly similar. Considering the histological organization of ovaries, they could be divided into two zones. Zone I (proximal, close to the connection with the septum) is tightly packed with germline and somatic cells. Germ cells are interconnected via intercellular bridges and thin strands of the central cytoplasm (known as cytophore) and form syncytial cysts. Cysts unite oogonia, early meiotic cells (till diplotene), and clustering cells develop synchronously. During diplotene, interconnected cells lose developmental synchrony; most probably, one cell per cyst grows faster than others, detaches from the cysts, and becomes an oocyte. The remaining cells grow slightly and are still interconnected via the thin and reticular cytophore; these cells are considered nurse cells. Zone II has a form of egg strings where growing oocytes are isolated one from another by thin somatic cells and form short cords. We present the ultrastructural details of germline and somatic cells. We propose the term "Amynthas" type of ovaries for this ovary organization. We suppose that such ovaries are characteristic of other megascolecids and related families.


Assuntos
Oligoquetos , Ovário , Humanos , Feminino , Animais , Ovário/ultraestrutura , Oócitos , Oogênese , Células Germinativas
3.
Toxicology ; 467: 153099, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35066102

RESUMO

Alginic acid (AA) is a kind of polysaccharide extracted from brown seaweeds and has been widely used in food industry. Certain positive effects of AA, such as anti-inflammation and anti-allergy, have been reported. Nevertheless, as a potential chemical contaminant of the environment, its impact on female reproductive system remains to be investigated. The purpose of this study is to explore the impact of AA on ovary and to investigate the further cellular mechanism. Primarily, in vitro cultured mouse ovary granulosa cells (GCs) were treated with AA at a concentration of 10µM for 24 h. The cells and supernatant were collected and subjected to further measures. The results demonstrated that after being treated with 10µM AA for 24 h the levels of estradiol and progesterone in supernatant were down-regulated. And excessive reactive oxygen species (ROS) and declined antioxidant capacity were also determined. Additionally, a large number of apoptotic bodies and autophagic vesicles were found in the experimental cells, and the mitochondria-mediated apoptotic pathway was demonstrated to play a main role in GCs apoptosis. To further investigate the effect of AA on ovary, the female ICR mice were administered with AA (10 mg/ kg bodyweight) intraperitoneally for successive 35 days, and the estrus phase was recorded simultaneously. After exposure, the ovaries and blood samples were collected for further analysis. The results revealed that the estrus period of the mice was shortened and the interestrus period was extended after being treated with AA for 35 days. At the organismal level, the numbers of antral follicles and atresia follicles increased and the levels of pro-apoptosis and autophagy-related proteins were detected upregulated after AA treatment. Taken together, both in vivo and in vitro data suggested that AA has toxicity on female reproduction by disrupting estrogen production and inducing oxidative stress, mitochondria-mediated apoptosis and autophagy. Our results provide new scientific basis and the concern for controlling the increasing use of AA.


Assuntos
Ácido Algínico/toxicidade , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Hormônios Esteroides Gonadais/metabolismo , Células da Granulosa/efeitos dos fármacos , Ovário/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Células Cultivadas , Estradiol/sangue , Ciclo Estral/sangue , Ciclo Estral/efeitos dos fármacos , Feminino , Hormônios Esteroides Gonadais/sangue , Células da Granulosa/metabolismo , Células da Granulosa/ultraestrutura , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Ovário/metabolismo , Ovário/ultraestrutura , Progesterona/sangue , Via Secretória , Fatores de Tempo
4.
Cells ; 10(10)2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34685641

RESUMO

Worldwide, dairy cows of the type of high-producing cattle (HPC) suffer from health and fertility problems at a young age and therefore lose productivity after an average of only three lactations. It is still contentious whether these problems are primarily due to genetics, management, feeding or other factors. Vascularization plays a fundamental role in the cyclic processes of reproductive organs, as well as in the regeneration of tissues. In a previous study, HPC were shown to have a greater ovarian corpus luteum vascularization compared to dual-purpose breeds. We hypothesize that this activated angiogenesis could likely lead to an early exhaustion of HPC's regenerative capacity and thus to premature reproductive senescence. The objective of this study was to investigate if a HPC breed (Holstein-Friesian, HF) exhibits higher ovarian angiogenesis than a dual-purpose breed (Polish Red cow, PR) and if this is related to early ovarian aging and finally reproductive failure. For this purpose, we assessed the degree of vascularization by means of ovarian blood vessel characterization using light microscopy. As indicators for aging, we measured ovarian mitochondrial size and telomere length in peripheral leukocytes. We report in this study that in both breeds the distance between capillaries became smaller with increasing age and that the mean telomere length decreased with increasing age. The only difference between the two breeds was that PR developed larger capillaries than HF. Neither a relationship between telomere length, nor the morphology of the mitochondrial apparatus and nor angiogenesis in HF was proven. Although the data trends indicated that the proportion of shortened telomeres in HF was higher than in the PR, no significant difference between the two breeds was detected.


Assuntos
Envelhecimento/fisiologia , Cruzamento , Capilares/fisiologia , Mitocôndrias/metabolismo , Ovário/irrigação sanguínea , Homeostase do Telômero , Animais , Bovinos , Feminino , Leucócitos Mononucleares/metabolismo , Mitocôndrias/ultraestrutura , Tamanho do Órgão , Folículo Ovariano/irrigação sanguínea , Folículo Ovariano/ultraestrutura , Ovário/ultraestrutura
5.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206462

RESUMO

Human fetal gonads acquire endocrine steroidogenic capabilities early during their differentiation. Genetic studies show that this endocrine function plays a central role in the sexually dimorphic development of the external genitalia during fetal development. When this endocrine function is dysregulated, congenital malformations and pathologies are the result. In this review, we explain how the current knowledge of steroidogenesis in human fetal gonads has benefited from both the technological advances in steroid measurements and the assembly of detailed knowledge of steroidogenesis machinery and its expression in human fetal gonads. We summarise how the conversion of radiolabelled steroid precursors, antibody-based assays, mass spectrometry, ultrastructural studies, and the in situ labelling of proteins and mRNA have all provided complementary information. In this review, our discussion goes beyond the debate on recommendations concerning the best choice between the different available technologies, and their degrees of reproducibility and sensitivity. The available technologies and techniques can be used for different purposes and, as long as all quality controls are rigorously employed, the question is how to maximise the generation of robust, reproducible data on steroid hormones and their crucial roles in human fetal development and subsequent functions.


Assuntos
Feto/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Gônadas/metabolismo , Pesquisa , Feminino , Humanos , Imunoensaio , Masculino , Espectrometria de Massas , Ovário/metabolismo , Ovário/ultraestrutura , Pesquisa/tendências , Desenvolvimento Sexual/genética , Testículo/metabolismo , Testículo/ultraestrutura
6.
J Assist Reprod Genet ; 38(10): 2581-2590, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34331619

RESUMO

PURPOSE: To investigate whether mitochondrial content, activity, and morphology differ in prepubertal versus adult ovarian follicles. METHODS: Ovarian tissue was collected from 7 prepubertal girls (age 1-10 years) and 6 adult women (age 20-35 years). Primordial and primary follicles were isolated from frozen-thawed prepubertal and adult ovarian tissue and their viability was assessed. Mitochondrial content was investigated by TOMM20 immunostaining of prepubertal and adult ovarian tissue, while mitochondrial activity in isolated follicles was analyzed by MitoTracker CM-H2XRos and JC-1. Frozen-thawed ovarian tissue from the same patients was also evaluated by transmission electron microscopy to examine mitochondrial morphology. RESULTS: Higher TOMM20 staining was detected in prepubertal follicles compared to their adult counterparts, indicating the presence of more mitochondria in prepubertal follicles. Analysis of mitochondrial activity by MitoTracker showed higher fluorescence intensity in prepubertal follicles, suggesting that follicles in this group are more active than adult follicles. JC-1 analysis did not reveal any statistically significant difference in the inactive/active ratio between the two groups. Moreover, ultrastructural analysis by TEM detected morphological differences in the shape and cristae of prepubertal mitochondria, probably suggesting a mechanism of response to autophagy. CONCLUSION: Differences in the number, activity, and morphology of mitochondria were reported, suggesting that consequential modifications might occur during puberty, which could be the window of opportunity required by mitochondria to undergo changes needed to reach maturity, and hence the capacity for ovulation and fertilization.


Assuntos
Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Doenças Ovarianas/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Puberdade/metabolismo , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Criopreservação , Feminino , Humanos , Lactente , Microscopia Eletrônica de Transmissão , Doenças Ovarianas/patologia , Folículo Ovariano/ultraestrutura , Ovário/ultraestrutura , Adulto Jovem
7.
Commun Biol ; 4(1): 710, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112923

RESUMO

Immunocytochemistry visualizes the exact spatial location of target molecules. The most common strategy for ultrastructural immunocytochemistry is the conjugation of nanogold particles to antibodies as probes. However, conventional nanogold labelling requires time-consuming nanogold probe preparation and ultrathin sectioning of cell/tissue samples. Here, we introduce an in situ strategy involving nanogold nucleation in immunoenzymatic products on universal paraffin/cryostat sections and provide unique insight into nanogold development under hot-humid air conditions. Nanogold particles were specifically localized on kidney podocytes to target synaptopodin. Transmission electron microscopy revealed secondary growth and self-assembly that could be experimentally controlled by bovine serum albumin stabilization and phosphate-buffered saline acceleration. Valuable retrospective nanogold labelling for gastric H+/K+-ATPase was achieved on vintage immunoenzymatic deposits after a long lapse of 15 years (i.e., 15-year-old deposits). The present in situ nanogold labelling is anticipated to fill the gap between light and electron microscopy to correlate cell/tissue structure and function.


Assuntos
Ouro/análise , Nanopartículas Metálicas/análise , Animais , Feminino , Imuno-Histoquímica , Rim/ultraestrutura , Masculino , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/análise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Ovário/ultraestrutura , Coelhos , Ratos Wistar , Coloração e Rotulagem
8.
Reprod Biomed Online ; 42(5): 859-869, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33832866

RESUMO

RESEARCH QUESTION: Are there differences in the composition and structure of the basal lamina surrounding follicles in prepubertal versus adult human ovarian tissue? DESIGN: Frozen-thawed human ovarian tissue from six prepubertal and seven adult patients was divided into three fragments in each case: two for non-grafted tissue evaluation and one for long-term xenografting to mice. Collagen IV and laminin expression were investigated by immunohistochemistry before and after grafting. The basal lamina was analysed by transmission electron microscopy on frozen-thawed tissue. RESULTS: In frozen-thawed tissue, collagen IV was significantly less expressed around prepubertal follicles than around adult follicles (primordial, P = 0.02; intermediate/growing follicles, P = 0.03), while laminin was significantly more expressed (primordial, P = 0.03; intermediate, P = 0.01). Collagen IV expression was significantly higher around prepubertal primordial follicles in grafted tissue than in non-grafted tissue, reaching similar levels to those in adult tissue. Ultrastructure analysis showed the basal lamina around follicles in prepubertal frozen-thawed tissue to be rather patchy and thinner than around adult follicles (primordial/intermediate, P = 0.001; primary, P = 0.02). CONCLUSIONS: In frozen-thawed tissue, the basal lamina around prepubertal follicles is less mature than around adult follicles, but it becomes similar in both prepubertal and adult subjects after grafting. Grafting could therefore induce maturation of the basal lamina around prepubertal follicles.


Assuntos
Membrana Basal/ultraestrutura , Criopreservação , Ovário/ultraestrutura , Desenvolvimento Sexual , Transplante Heterólogo , Adulto , Animais , Membrana Basal/crescimento & desenvolvimento , Membrana Basal/metabolismo , Criança , Pré-Escolar , Colágeno Tipo IV/metabolismo , Feminino , Humanos , Lactente , Laminina/metabolismo , Camundongos SCID , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Adulto Jovem
9.
Methods Mol Biol ; 2346: 79-90, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33460026

RESUMO

The Drosophila ovary is an exceptional model for studying cell-cell interactions in vivo. Cells communicate with each other in a highly coordinated manner. Accurate spatiotemporal regulation of cell-cell interaction is critical for the development of eggs. Ultrastructural analysis using electron microscopy (EM) permits the visualization of both cells and subcellular signaling structures with high resolution. Here we describe a method for the processing of intact fly ovaries by scanning electron microscopy (SEM).


Assuntos
Ovário/ultraestrutura , Animais , Comunicação Celular , Drosophila , Feminino , Ovário/citologia
10.
Front Endocrinol (Lausanne) ; 12: 791071, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975760

RESUMO

The number of mitochondria in the oocyte along with their functions (e.g., energy production, scavenger activity) decline with age progression. Such multifaceted functions support several processes during oocyte maturation, ranging from energy supply to synthesis of the steroid hormones. Hence, it is hardly surprising that their impairment has been reported in both physiological and premature ovarian aging, wherein they are crucial players in the apoptotic processes that arise in aged ovaries. In any form, ovarian aging implies the progressive damage of the mitochondrial structure and activities as regards to ovarian germ and somatic cells. The imbalance in the circulating hormones and peptides (e.g., gonadotropins, estrogens, AMH, activins, and inhibins), active along the pituitary-ovarian axis, represents the biochemical sign of ovarian aging. Despite the progress accomplished in determining the key role of the mitochondria in preserving ovarian follicular number and health, their modulation by the hormonal signalling pathways involved in ovarian aging has been poorly and randomly explored. Yet characterizing this mechanism is pivotal to molecularly define the implication of mitochondrial dysfunction in physiological and premature ovarian aging, respectively. However, it is fairly difficult considering that the pathways associated with ovarian aging might affect mitochondria directly or by altering the activity, stability and localization of proteins controlling mitochondrial dynamics and functions, either unbalancing other cellular mediators, released by the mitochondria, such as non-coding RNAs (ncRNAs). We will focus on the mitochondrial ncRNAs (i.e., mitomiRs and mtlncRNAs), that retranslocate from the mitochondria to the nucleus, as active players in aging and describe their role in the nuclear-mitochondrial crosstalk and its modulation by the pituitary-ovarian hormone dependent pathways. In this review, we will illustrate mitochondria as targets of the signaling pathways dependent on hormones and peptides active along the pituitary/ovarian axis and as transducers, with a particular focus on the molecules retrieved in the mitochondria, mainly ncRNAs. Given their regulatory function in cellular activities we propose them as potential diagnostic markers and/or therapeutic targets.


Assuntos
Estrogênios/fisiologia , Gonadotropinas Hipofisárias/fisiologia , Mitocôndrias/fisiologia , Ovário/fisiologia , RNA não Traduzido/fisiologia , Envelhecimento/fisiologia , Androgênios/fisiologia , Animais , Núcleo Celular/fisiologia , DNA Mitocondrial/genética , DNA Mitocondrial/fisiologia , Feminino , Atresia Folicular , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Mutação , Ovário/ultraestrutura , Transdução de Sinais
11.
J Morphol ; 282(1): 98-114, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33074563

RESUMO

Ovaries of Haplotaxis sp. were studied in active and nonactive states, that is, in a sexually mature specimen and in specimens outside of the reproductive period. Two pairs of ovaries were found in segments XI and XII. Especially in the nonactive state, they were in close contact with copulatory glands. Each ovary was composed of germ cells interconnected with syncytial cysts, which were enveloped by a layer of somatic cells. Within cysts each germ cell had one ring canal connecting it to the common anuclear cytoplasmic mass called a cytophore. During oogenesis clustering germ cells differentiated into nurse cells and oocytes; thus, the oogenesis was recognized as meroistic. Vitellogenic oocytes were detached from the ovaries and continued yolk absorption within the body cavity. Because recent studies have shown the variety of ovaries and germ line cyst organization in clitellates and suggest their evolutionary conservatism at the family or subfamily level, the data presented here can be valid in understanding the phylogenetic relationships among Clitellata. In this context, ovaries found in Haplotaxis sp. resembled those of the "Tubifex" type. "Tubifex" ovaries are characteristic for numerous microdrile taxa (tubificines, limnodriloidines, propappids, lumbriculids, and leech-like branchiobdellids) and can be regarded as the primary character for these Clitellata in which germ-line cysts are formed during early oogenesis. As the family Haplotaxidae is currently considered to be paraphyletic and the species studied here belongs to Haplotaxidae sensu stricto, our results support the close relationship of Haplotaxidae sensu stricto to the clade consisting of Lumbriculidae, Branchiobdellida, and Hirudinida, in which lumbriculids are sister to the latter two.


Assuntos
Oligoquetos/fisiologia , Oogênese/fisiologia , Ovário/anatomia & histologia , Ovário/fisiologia , Animais , Feminino , Células Germinativas/citologia , Oligoquetos/ultraestrutura , Oócitos/citologia , Oócitos/ultraestrutura , Ovário/ultraestrutura , Filogenia
12.
Protoplasma ; 258(1): 191-207, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33033944

RESUMO

This study reveals the ovary micromorphology and the course of oogenesis in the leech Batracobdella algira (Glossiphoniidae). Using light, fluorescence, and electron microscopies, the paired ovaries were analyzed. At the beginning of the breeding season, the ovaries were small, but as oogenesis progressed, they increased in size significantly, broadened, and elongated. A single convoluted ovary cord was located inside each ovary. The ovary cord was composed of numerous germ cells gathered into syncytial groups, which are called germ-line cysts. During oogenesis, the clustering germ cells differentiated into two functional categories, i.e., nurse cells and oocytes, and therefore, this oogenesis was recognized as being meroistic. As a rule, each clustering germ cell had one connection in the form of a broad cytoplasmic channel (intercellular bridge) that connected it to the cytophore. There was a synchrony in the development of the clustering germ cells in the whole ovary cord. In the immature leeches, the ovary cords contained undifferentiated germ cells exclusively, from which, previtellogenic oocytes and nurse cells differentiated as the breeding season progressed. Only the oocytes grew considerably, gathered nutritive material, and protruded at the ovary cord surface. The vitellogenic oocytes subsequently detached from the cord and filled tightly the ovary sac, while the nurse cells and the cytophore degenerated. Ripe eggs were finally deposited into the cocoons. A comparison of the ovary structure and oogenesis revealed that almost all of the features that are described in the studied species were similar to those that are known from other representatives of Glossiphoniidae, which indicates their evolutionary conservatism within this family.


Assuntos
Anfíbios/fisiologia , Sanguessugas/ultraestrutura , Oogênese/fisiologia , Ovário/ultraestrutura , Animais , Feminino
13.
Dev Biol ; 469: 111-124, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33141038

RESUMO

Although somatic cells play an integral role in animal gametogenesis, their organization and function are usually poorly characterized, especially in non-model systems. One such example is a peculiar cell found in leech ovaries - the apical cell (AC). A single AC can be found at the apical tip of each ovary cord, the functional unit of leech ovaries, where it is surrounded by other somatic and germline cells. The AC is easily distinguished due to its enormous size and its numerous long cytoplasmic projections that penetrate the space between neighboring cells. It is also characterized by a prominent accumulation of mitochondria, Golgi complexes and electron-dense vesicles. ACs are also enriched in cytoskeleton, mainly in form of intermediate filaments. Additionally, the AC is connected to neighboring cells via junctions that structurally resemble hemidesmosomes. In spite of numerous descriptive data about the AC, its functions remain poorly understood. Its suggested functions include a role in forming skeleton for the germline cells, and a role in defining a niche for germline stem cells. The latter is more speculative, since germline stem cells have not been identified in leech ovaries. Somatic cells with similar morphological properties to those of the AC have been found in gonads of nematodes - the distal tip cell - and in insects - Verson's cell, hub cells and cap cells. In the present article we summarize information about the AC structure and its putative functions. AC is compared with other well-described somatic cells with potentially similar roles in gametogenesis.


Assuntos
Sanguessugas/citologia , Ovário/citologia , Animais , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Feminino , Oogênese , Ovário/fisiologia , Ovário/ultraestrutura , Nicho de Células-Tronco
14.
J Ovarian Res ; 13(1): 121, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33054849

RESUMO

BACKGROUND: Accurate evaluation of primordial follicle numbers in mouse ovaries is an essential endpoint for studies investigating how endogenous and exogenous insults, such as maternal aging and chemotherapy, impact the ovarian reserve. In this study, we compared and contrasted two methods for counting healthy primordial follicles following exposure to cyclophosphamide (75 mg/kg), a well-established model of follicle depletion. The first was the fractionator/optical dissector technique, an unbiased, assumption-free stereological approach for quantification of primordial follicle numbers. While accurate, highly reproducible and sensitive, this method relies on specialist microscopy equipment and software, requires specific fixation, embedding and sectioning parameters to be followed, and is largely a manual process that is tedious and time-consuming. The second method was the more widely used serial section and direct count approach, which is relatively quick and easy. We also compared the impacts of different fixatives, embedding material and section thickness on the overall results for each method. RESULTS: Direct counts resulted in primordial follicle numbers that were significantly lower than those obtained by stereology, irrespective of fixation and embedding material. When applied to formalin fixed tissue, the direct count method did not detect differences in follicle numbers between saline and cyclophosphamide treated groups to the same degree of sensitivity as the gold standard stereology method (referred to as the Reference standard). However, when Bouin's fixative was used, direct counts and stereology were comparable in their ability to detect follicle depletion caused by cyclophosphamide. CONCLUSIONS: This work indicates that the direct count method can produce similar results to stereology when Bouin's fixative is used instead of formalin. The findings presented here will assist others to select the most appropriate experimental approach for accurate follicle enumeration, depending on whether the primary objective of the study is to determine absolute primordial follicle numbers or relative differences between groups.


Assuntos
Folículo Ovariano/ultraestrutura , Ovário/ultraestrutura , Animais , Feminino , Camundongos
15.
Micron ; 138: 102929, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32896812

RESUMO

This is the first report that describes histological and ultrastructural details of ovary organization in haemadipsid leeches. In Haemadipsa japonica, the female reproductive system is organized similar to that of other haemadipsids. Each of the paired and oval ovaries of H. japonica is comprised of the ovary wall (ovisac), which encloses two elongated, thread-like ovarian units termed ovary cords. Ovary cords are comprised of germ-line cells and associated somatic cells. Each cord is polarized and contains germ-line cells in the consecutive developmental stages that are sequentially located along the long cord axis. There were three zones in each cord: the club-shaped apical part, the thread-like middle part, and the basal-most end, which contains degenerating germ cells. Outside of the reproductive period, the middle part of the cord in leeches is smooth, and no growing oocytes are visible; alternatively, in mature specimens, several growing oocytes protrude from the cord, and several huge vitellogenic oocytes that are completely detached from the cord occur within the ovisac. Ovary cord organization and functioning in H. japonica are very similar to the 'Hirudo' type cords that were found in several hirudiniform leeches. This conclusion supports the view that all hirudiniform leeches have conservative ovary cord organization and a similar pattern of oogenesis. Germ-line cyst composition, architecture, and functioning were also found to be evolutionarily conservative characteristics when compared with all previously examined Clitellata. In the germ-line cysts found in H. japonica each cell is connected to the central and anuclear cytoplasmic mass (cytophore) via one intercellular bridge, and, as oogenesis progresses, the fate of interconnected cell diversifies: some of them (oocytes) grow and complete oogenesis, but the majority become nurse cells and finally degenerate. Thus, oogenesis in H. japonica, similar to other clitellates, can be considered meroistic.


Assuntos
Sanguessugas/anatomia & histologia , Microscopia Eletrônica de Transmissão/métodos , Ovário/citologia , Ovário/ultraestrutura , Animais , Feminino , Células Germinativas , Sanguessugas/ultraestrutura , Oócitos/ultraestrutura , Oogênese , Ovário/anatomia & histologia
16.
Tissue Cell ; 66: 101395, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32933718

RESUMO

The ovarian development of Callinectes ornatus and Arenaeus cribrarius was described using histochemistry and ultrastructure. Both species shows the same ovarian stages, which are the juvenile (JUV), adult rudimentary (RUD), developing (DEV), intermediary (INT), mature (MAT), and spent (OV) stages. The JUV and RUD stages showed similar characteristics, and previtellogenesis is characterized by meiotic prophase chromosomes. In the primary vitellogenesis, the oocyte cytoplasm shows many small and large cytoplasmic glycoprotein vesicles. These vesicles correspond to the dilated cisternae of the rough endoplasmic reticulum (RER), which produces the immature (endogenous) yolk. Secondary vitellogenesis (exogenous phase) begins at the DEV stage with the fusion of pinocytic vesicles and vesicles with immature yolks to form mature yolk granules. At the INT stage, the formation of the chorion begins, and the mature yolks increase in size and number, while the RER diminishes. In the MAT stage, the oocytes are completely formed, and the cytoplasm is filled with mature yolk, lipid droplets, and glycogen. There are no significant variations between the gonadosomatic and hepatosomatic indices, which allows us to infer that the transfer of reserves from the hepatopancreas is nearly constant during ovarian development, since we observed primiparous and multiparous females in the same sampled population.


Assuntos
Braquiúros/ultraestrutura , Ovário/ultraestrutura , Natação , Exoesqueleto/ultraestrutura , Animais , Feminino , Oócitos/citologia , Oócitos/ultraestrutura , Oogônios/citologia , Oogônios/ultraestrutura , Vitelogênese
17.
Gynecol Oncol ; 159(2): 527-533, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32977988

RESUMO

OBJECTIVE: Measure the size and shape of talc particles in talcum powder and compare this data to the size and shape of talc particles found in surgically resected tissues from patients with ovarian carcinoma. METHODS: Using polarized light microscopy (PLM) and scanning electron microscopy (SEM), we measured the size and shape of talc particles in samples of talc-containing baby powder (TCBP) and surgically resected pelvic tissues (hysterectomies) from talc-exposed patients with ovarian carcinoma. RESULTS: The most frequent class of particles in TCBP can be unequivocally identified as talc, using both polarized light microscopy and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDX). The talc particles found in resected tissues from ovarian carcinoma patients are similar in size and shape to the most abundant morphological class of particles in TCBP. CONCLUSIONS: This finding, combined with previous epidemiological literature and tissue-based analytical studies, provides further evidence that the small, isodiametric particles that dominate TCBP can migrate from the perineum and become lodged in distal structures in the female reproductive tract, where they may lead to an increased risk of developing ovarian carcinoma.


Assuntos
Linfonodos/química , Omento/química , Ovário/química , Talco/análise , Adulto , Idoso , Carcinoma Epitelial do Ovário/patologia , Feminino , Humanos , Linfonodos/ultraestrutura , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Omento/ultraestrutura , Neoplasias Ovarianas/patologia , Ovário/ultraestrutura , Talco/efeitos adversos , Talco/farmacocinética
18.
Ticks Tick Borne Dis ; 11(6): 101507, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32993927

RESUMO

The present study was carried out to assess the effects on the ovary of fed female Argas persicus following spraying of the ticks with spores of the fungus Beauveria bassiana suspended in triton X100 at a concentration of 107 conidia/mL. Scanning and transmission electron microscopy observations provided evidence that B. bassiana invaded the ovary, causing extensive morphological damage and deterioration of the developing oocytes. Destruction of the shape and internal organelles of young and previtellogenic oocytes and complete inhibition of vitellogenesis was evident. This histopathological study is the first demonstration of ultrastructural damage in the ovaries of A. persicus after infection with B. bassiana. The data presented confirm that B. bassiana affects the ovary either directly by entering the oocytes and/or indirectly by producing toxins in the haemolymph that interfere with the development of oocytes, thus potentially contributing to the control of this tick in a way that is safe for its host and the environment.


Assuntos
Argas/ultraestrutura , Beauveria/fisiologia , Controle Biológico de Vetores , Controle de Ácaros e Carrapatos , Animais , Argas/microbiologia , Feminino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Ovário/microbiologia , Ovário/ultraestrutura
19.
Ecotoxicol Environ Saf ; 206: 111190, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32871518

RESUMO

Radiotherapy represents a critical component in cancer treatment. However, premature ovarian failure (POF) is a major hurdle of deleterious off-target effects in young females, which, therefore, call for an effective radioprotective agent. The present study aimed to explore the molecular mechanism underlying the protective effects of N-acetyl-L-cysteine (NAC) against γ-radiation-provoked POF. Immature female Sprague-Dawley rats were orally-administered NAC (50 mg/kg) and were exposed to a single whole-body dose of 3.2 Gy ϒ-radiation. NAC administration remarkably reversed abnormal serum estradiol and anti-Müllerian hormone levels by 73% and 40%, respectively while ameliorating the histopathological and ultrastructural alterations-triggered by γ-radiation. Mechanistically, NAC alleviated radiation-induced oxidative damage through significantly increased glutathione peroxidase activity by 102% alongside with decreasing NADPH oxidase subunits (p22 and NOX4) gene expressions by 48% and 38%, respectively compared to the irradiated untreated group. Moreover, NAC administration achieved its therapeutic effect by inhibiting ovarian apoptosis-induced by radiation through downregulating p53 and Bax levels by 33% and 16%, respectively while increasing the Bcl-2 mRNA expression by 135%. Hence, the Bax/Bcl2 ratio and cytochrome c expression were subsequently reduced leading to decreased caspase 3 activity by 43%. Importantly, the anti-apoptotic property of NAC could be attributed to inactivation of MAPK signaling molecules; p38 and JNK, and enhancement of the ovarian vascular endothelial growth factor (VEGF) expression. Taken together, our results suggest that NAC can inhibit radiotherapy-induced POF while preserving ovarian function and structure through upregulating VEGF expression and suppressing NOX4/MAPK/p53 apoptotic signaling.


Assuntos
Acetilcisteína/farmacologia , Raios gama/efeitos adversos , Ovário/efeitos dos fármacos , Insuficiência Ovariana Primária/prevenção & controle , Protetores contra Radiação/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos da radiação , NADPH Oxidase 4/metabolismo , Ovário/metabolismo , Ovário/efeitos da radiação , Ovário/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Insuficiência Ovariana Primária/etiologia , Insuficiência Ovariana Primária/metabolismo , Insuficiência Ovariana Primária/patologia , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
J Morphol ; 281(10): 1160-1172, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32808691

RESUMO

Pseudoscorpiones (pseudoscorpions, false scorpions) is an order of small terrestrial chelicerates. While most chelicerates are lecithotrophic, that is, embryos develop due to nutrients (mostly yolk) deposited in the oocyte cytoplasm, pseudoscorpions are matrotrophic, that is, embryos are nourished by the female. Pseudoscorpion oocytes contain only a small amount of yolk. The embryos develop within a brood sac carried on the abdominal site of the female and absorb nutrients by a pumping organ. It is believed that in pseudoscorpions nutrients for developing embryos are produced in the ovary during a postovulatory (secretory) phase of the ovarian cycle. The goal of our study was to analyze the structure of the female reproductive system during the secretory phase in the pseudoscorpion Chelifer cancroides, a representative of the family Cheliferidae, considered to be one of the most advanced pseudoscorpion taxa. We use diverse microscopic techniques to document that the nutritive fluid is produced not only in the ovaries but also by the epithelial cells in the oviducts. The secretory active epithelial cells are hypertrophic and polyploid and release their content by fragmentation of apical parts. Our observations also indicate that fertilization occurs in the oviducts. Moreover, in contrast to previous findings, we show that secretion of the nutritive material starts when the fertilized oocytes reach the brood sac and thus precedes formation of the pumping organ. Summing up, we show that C. cancroides exhibits traits of advanced adaptations for matrotrophy due to coordinated secretion of the nutritive fluid by the ovarian and oviductal epithelial cells, which substantially increases the efficiency of nutritive fluid formation. Since the secretion of nutrients starts before formation of the pumping organ, we suggest that the embryos are able to absorb the nutritive fluid also in the early embryonic stages.


Assuntos
Adaptação Fisiológica , Aracnídeos/anatomia & histologia , Genitália Feminina/anatomia & histologia , Animais , Aracnídeos/embriologia , Aracnídeos/ultraestrutura , Desenvolvimento Embrionário , Células Epiteliais/citologia , Feminino , Genitália Feminina/ultraestrutura , Lipídeos/análise , Oócitos/citologia , Ovário/anatomia & histologia , Ovário/embriologia , Ovário/ultraestrutura , Oviductos/anatomia & histologia , Oviductos/ultraestrutura , Ovulação , Polissacarídeos/análise , Proteínas/análise
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