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sion="1.0" encoding="utf-8"?> RD Reproduction, Fertility and Development Reprod. Fertil. Dev. 1031-3613 1448-5990 CSIRO Publishing 36 Gardiner Road Clayton 3168 Victoria Australia RD24134 10.1071/RD24134 Foreword Dedication to Jim Cummins Spermatology and testis biology - honouring the contributions of James M. Cummins M. Yeste and G. B. Martin https://orcid.org/0000-0002-2209-340X Yeste Marc A * https://orcid.org/0000-0002-1905-7934 Martin Graeme B. B Department of Biology, Faculty of Sciences, University of Girona , Girona , Spain . Faculty of Agriculture and Natural Sciences, University of Western Australia , Stirling Highway , Crawley , WA , Australia . * Correspondence to: Marc Yeste Department of Biology, Faculty of Sciences, University of Girona, Girona, Spain Email: marc.yeste@udg.edu 12 September 2024 36 15 Collection: Dedication to Jim Cummins RD24134 17 August 2024 Received: 17 August 2024 20 August 2024 Accepted: 20 August 2024 12 September 2024 Published: 12 September 2024 © 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing 2024 The Author(s) (or their employer(s)). This collection celebrates the important contributions James (Jim) Michael Cummins made to the field of reproductive biology. It covers a variety of topics but with a clear focus on spermatology where Jim's impact, as a scientist and teacher, was most profound. As a core member of the Editorial Board of Reproduction, Fertility and Development , for a series of Editors-in-Chief, he was a font of wisdom for all aspects of the field, including reproductive technology in humans, and acted as a guardian of editorial principles and ethics. This article belongs to the Collection Dedication to Jim Cummins.
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Testículo , Masculino , Testículo/fisiología , Humanos , Historia del Siglo XX , Historia del Siglo XXI , Espermatogénesis/fisiología , Australia , AnimalesRESUMEN
Extracellular membrane proteins are crucial for mediating cell attachment, recognition, and signal transduction in the testicular microenvironment, particularly germline stem cells. Cadherin 18 (CDH18), a type II classical cadherin, is primarily expressed in the nervous and reproductive systems. Here, we investigated the expression of CDH18 in neonatal porcine prospermatogonia (ProSGs) and murine spermatogonial stem cells (SSCs). Disruption of CDH18 expression did not adversely affect cell morphology, proliferation, self-renewal, or differentiation in cultured porcine ProSGs, but enhanced cell adhesion and prolonged cell maintenance. Transcriptomic analysis indicated that the down-regulation of CDH18 in ProSGs significantly up-regulated genes and signaling pathways associated with cell adhesion. To further elucidate the function of CDH18 in germ cells, Cdh18 knockout mice were generated, which exhibited normal testicular morphology, histology, and spermatogenesis. Transcriptomic analysis showed increased expression of genes associated with adhesion, consistent with the observations in porcine ProSGs. The interaction of CDH18 with ß-catenin and JAK2 in both porcine ProSGs and murine SSCs suggested an inhibitory effect on the canonical Wnt and JAK-STAT signaling pathways during CDH18 deficiency. Collectively, these findings highlight the crucial role of CDH18 in regulating cell adhesion in porcine ProSGs and mouse SSCs. Understanding this regulatory mechanism provides significant insights into the testicular niche.
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Cadherinas , Adhesión Celular , Animales , Masculino , Porcinos , Adhesión Celular/fisiología , Ratones , Cadherinas/metabolismo , Cadherinas/genética , Ratones Noqueados , Espermatogonias/metabolismo , Espermatogonias/fisiología , Testículo/metabolismo , Testículo/fisiología , Células Madre Germinales Adultas/metabolismo , Células Madre Germinales Adultas/fisiología , Regulación de la Expresión Génica , Células Madre/fisiología , Células Madre/metabolismoRESUMEN
Osteoglossomorpha, the bony tongue fishes, show great variation in morphology, behavioural strategies, reproductive biology and gamete ultrastructure. The order Osteoglossiformes is the only vertebrate taxon, in which four types of sperm (monoflagellate, biflagellate and aflagellate aquasperm and the complex introsperm) have been described. It is also the only vertebrate lineage in which aflagellate spermatozoa exist. The aim of this study was to analyse the structure of the testis and the process of spermiogenesis in the mormyrid Campylomormyrus compressirostris during the breeding season using light and electron microscopy (transmission and scanning). Males of this species have a single testis of the anastomosing tubular type. The tubules of the anterior part of the testis contain cysts with developing germ cells, and this region is much wider than the posterior part, which consists of efferent ducts filled with sperm cells. The cysts are filled with single or mitotic spermatogonia, primary and secondary spermatocytes and early spermatids. At the stage of spermatids with fine granular chromatin, the cysts rupture and successive stages of spermatid differentiation take place in the testicular lumen; we therefore characterise this process as 'extracystic spermiogenesis'. Sperm development in C. compressirostris is extremely simple and involves chromatin condensation in the central region of the nucleus, a slight decrease in nuclear volume, the appearance of numerous vesicles in the cytoplasm that form a tubular-vesicular system at the base of the nucleus. Both centrioles and mitochondria are translocated to the peripheral region of the midpiece, which forms the opposite pole to the nucleus. There are many differences between the types of spermiogenesis described so far in teleosts and that found in C. compressirostris, including the loss of flagellum formation. This unique type of spermiogenesis is restricted to species of the families Mormyridae and Gymnarchidae, all of which possess aflagellate spermatozoa. Our data demonstrate that the spermatid differentiation and existence of the aflagellate spermatozoon are a unique phenomena not only among teleosts but also in the whole vertebrate lineage.
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Peces , Espermatogénesis , Espermatozoides , Testículo , Animales , Masculino , Espermatogénesis/fisiología , Espermatozoides/fisiología , Espermatozoides/ultraestructura , Testículo/ultraestructura , Testículo/fisiología , Peces/fisiologíaRESUMEN
Daurian ground squirrels (Spermophilus dauricus) experience various stress states during winter hibernation, but the impact on testicular function remains unclear. This study focused on the effects of changes in testicular autophagy, apoptosis, and mitochondrial homeostasis signaling pathways at various stages on the testes of Daurian ground squirrels. Results indicated that: (1) During winter hibernation, there was a significant increase in seminiferous tubule diameter and seminiferous epithelium thickness compared to summer. Spermatogonia number and testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels were higher during inter-bout arousal, suggesting that the testes remained stable during hibernation. (2) An increased number of mitochondria with intact morphology were observed during hibernation, indicating that mitochondrial homeostasis may contribute to testicular stability. (3) DNA fragmentation was evident in the testes during the hibernation and inter-bout arousal stages, with the highest level of caspase3 enzyme activity detected during inter-bout arousal, together with elevated levels of Bax/Bcl-2 and Lc3 II/Lc3 I, indicating an up-regulation of apoptosis and autophagy signaling pathways during hibernation. (4) The abundance of DRP1, MFF, OPA1, and MFN2 proteins was increased, suggesting an up-regulation of mitochondrial dynamics-related pathways. Overall, testicular autophagy, apoptosis, and mitochondrial homeostasis-related signaling pathways were notably active in the extreme winter environment. The well-maintained mitochondrial morphology may favor the production of reproductive hormones and support stable testicular morphology.
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Apoptosis , Autofagia , Hibernación , Dinámicas Mitocondriales , Sciuridae , Testículo , Animales , Masculino , Sciuridae/fisiología , Sciuridae/metabolismo , Hibernación/fisiología , Testículo/metabolismo , Testículo/fisiología , Autofagia/fisiología , Mitocondrias/metabolismo , Estaciones del Año , Testosterona/metabolismo , Hormona Folículo Estimulante/metabolismo , Hormona Luteinizante/metabolismoRESUMEN
The testis serves as the reproductive gland in male mammals, primarily tasked with the production of sperm and synthesis of androgens. A complex signaling network consisting of various cell types, including germ cells, Sertoli cells, and Leydig cells, supports the structure and maintains the function of the testis. Apart from the hypothalamic-pituitary-gonadal axis, various sex hormones and cytokines are also implicated in the regulation of testicular function. The fibroblast growth factor (FGF) represents a crucial class of active cytokines that stimulate cell proliferation, induce tissue differentiation, and govern organ development. This review summarizes the molecular mechanisms of FGF regulating testicular development and spermatogenesis and maintaining male fertility.
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Factores de Crecimiento de Fibroblastos , Espermatogénesis , Testículo , Masculino , Espermatogénesis/fisiología , Testículo/metabolismo , Testículo/fisiología , Humanos , Factores de Crecimiento de Fibroblastos/metabolismo , Factores de Crecimiento de Fibroblastos/fisiología , Animales , Reproducción/fisiologíaRESUMEN
PURPOSE: The gubernaculum seems to be the most important anatomical structure in the testicular migration process. The objective of this paper is to review current literature regarding the role of gubernaculum testis nerves in testicular migration. We conducted a comprehensive literature review about the gubernaculum testis innervation. A PubMed database search was performed in April 2024, focusing on gubernaculum testis and cryptorchidism and genitofemoral nerve (GFN) and calcitonin gene-related peptide (CGRP) gene. The gubernaculum has its own nerve supply, the GFN, descending on the anteromedial surface of the psoas muscle from L1-L2 segments. The second phase of testicular descent is regulated by androgens and CGRP, released from the sensory nucleus of the GFN. The GFN doesn't directly play a role in testicular migration but there is a theory that shows a regulatory function of this nerve in hormonal action during this process. The gubernaculum testis has important structural alterations during the testicular migration and the genitofemoral nerve and CGRP gene are of great importance in this process. The genitofemoral nerve provides motor innervation to the cremaster muscle and gubernaculum, which helps regulate the position of the testes within the scrotum.
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Criptorquidismo , Gubernáculo , Testículo , Humanos , Masculino , Testículo/fisiología , Testículo/embriología , Gubernáculo/fisiología , Gubernáculo/embriología , Péptido Relacionado con Gen de Calcitonina/fisiología , Feto/fisiologíaRESUMEN
The Temminck's pangolin (Smutsia temminckii) is one of eight pangolin species worldwide and the only pangolin present in southern Africa. Historically, pangolins have not been able to reproduce successfully in captivity and this may be in part due to the lack of knowledge and understanding with regards to the pangolin reproductive system (anatomy, physiology, biology) in all eight species. This original study describes the gross anatomy of the male Temminck's pangolin from three adult individuals investigated. The male Temminck's pangolin presented a short, conical penis with ascrotal (internal) testes, similar to many other myrmecophagous mammals such as the aardvark (Orycteropus sp.) and anteaters (suborder: Vermilingua). However, the orientation of the penis of the Temminck's pangolin differed in that it was oriented cranioventrally, in contrast to the caudal orientation of the giant anteater. The testes were found to be bilaterally flattened with an elongate oval shape, similar to the aardvark. The specific characteristics of the reproductive tract of the male Temminck's pangolins are thought to be adaptations to their peculiar lifestyle as the male portrays characteristics that indicate adaptation to a lower basal metabolic rate and body temperature as well as to their defensive mechanism of rolling up into a ball. Our study suggests the male Temminck's pangolin reproductive anatomy is most similar and comparable to the Xenarthrans and the aardvark that display the same fossorial activities as pangolins, and the male morphology is not comparable to the phylogenetically closely-related Carnivora.
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Pangolines , Pene , Testículo , Animales , Masculino , Testículo/anatomía & histología , Testículo/fisiología , Pangolines/anatomía & histología , Pangolines/fisiología , Pene/anatomía & histología , Genitales Masculinos/anatomía & histología , Reproducción/fisiologíaRESUMEN
Dimensions of linear type traits facilitate selection of livestock for breeding and rearing. To date, use of linear type traits for selection of breeding bulls is highly concentric to scrotal circumference (SC), with probable overlook to other important traits. Present study reported the importance of various gonadal linear type traits on spermatozoa production, age-related changes in gonadal linear type traits of bulls and predictive ability of these traits on bulls' reproductive potentials. Among all gonadal traits, testicular density (TD), scrotal volume (SV), paired testicular weight (PWT) and SC were found most important predictor variables in order, which can discriminate between good/poor breeding bulls, that is, produced frozen semen doses (FSD) or not. Dimensions of gonadal traits increased significantly up to 36 months age and thereafter, development became slow and negligible. In contrast, TD decreased by 30%, 51%, 64%, 68% and 71% at 12, 24, 36, 48 and >49 months age, respectively, from its base value at 6 months. Bulls of lower TD (≤0.88 g/cm3) had significantly higher ejaculate volume (+9%), sperm motility, sperm concentration (+100 million/mL) and sperm output (+26%)/ejaculate as compared to bulls of higher TD (>0.88 g/cm3). Discriminant function was developed using TD, SV, PWT and SC to identify bulls of superior reproductive potentials. It was concluded that among the investigated traits, TD was the strongest to discriminate between FSD and Non-FSD bulls. Therefore, our findings suggested that TD could be more potential trait than SC for dairy bulls' breeding soundness evaluation and assessment of reproductive ability.
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Cruzamiento , Escroto , Testículo , Animales , Masculino , Bovinos/fisiología , Testículo/fisiología , Testículo/anatomía & histología , Escroto/anatomía & histología , Escroto/fisiología , Reproducción/fisiología , Motilidad Espermática , Análisis de Semen/veterinaria , Tamaño de los Órganos , Espermatozoides/fisiología , Recuento de Espermatozoides/veterinaria , Preservación de Semen/veterinaria , Industria LecheraRESUMEN
Although the order Rodentia does not present a high risk of extinction compared to mammals as a whole, several families demonstrate high levels of threat and/or data deficiency, therefore highlighting the need for targeted research and the application of ecological and reproductive data to the development of conservation actions. The order Rodentia, the largest among mammals, includes 9 families, and the family Cricetidae is the most diverse of the Brazilian rodents. In Brazil, 12 of the 16 genera of Oecomys are found. Oecomys bicolor is known in Brazil as the 'arboreal rat' and is, found in dry, deciduous and tropical forests. The mean body weight of Oecomys bicolor was 35.8 g and the gonadal, tubular and epithelial somatic indexes were, 0.53%, 0.47% and 0.37%, respectively. Seminiferous tubules volume density was 89.72% and the mitotic and meiotic indexes corresponded to 8.59 and 2.45 cells, respectively, and the yield of spermatogenesis was 23.83 cells. The intertubular compartment represented 10.28% of the testis parenchyma and around 5% of the interstitial space was occupied by Leydig cells, whose number per gram of testis was 11.10 × 107 cells. By evaluating the biometric and histomorphometric characteristics of the testis, there is evidence that this species has a high investment in reproduction. Due to the high contribution of the seminiferous epithelium and the intertubular compartment in this species, compared to the others of the same family, it is possible to infer that the species Oecomys bicolor has a promiscuous reproductive behaviour.
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Arvicolinae , Células Intersticiales del Testículo , Espermatogénesis , Testículo , Animales , Espermatogénesis/fisiología , Masculino , Testículo/anatomía & histología , Testículo/fisiología , Células Intersticiales del Testículo/citología , Células Intersticiales del Testículo/fisiología , Arvicolinae/anatomía & histología , Arvicolinae/fisiología , Túbulos Seminíferos/anatomía & histología , BrasilRESUMEN
In avian species, male fertility significantly impacts reproductive success. This study investigates the relationship between proctodeal gland size in male Japanese quails and sperm function, as well as female fertility duration. Six hundred adult Japanese quails were selected and housed in individual cages. Males (n = 300) were divided into 6 groups (50/group) based on the size of their proctodeal glands. Females (n = 300) were randomly assigned to corresponding groups. After acclimatization, sperm kinematics and the frequency and weight of foam discharge were evaluated. Males were paired with females for 24 h, and eggs were collected for 20 d postcopulation. Eggs were incubated to assess fertility duration. Fresh eggs (n = 20/group/d) were used to assess sperm penetration into the perivitelline membrane on the 2nd, 9th, and 16th d postinsemination. Plasma testosterone levels and the testes' relative weight were determined. The results indicated a significant increase (p < 0.0001) in sperm concentration, total and progressive motility, and nearly all sperm kinematic parameters such as VSL, VCL, VAP, LIN, WOB, and STR values as the size of the proctodeal gland increased. Quails copulated with males having a small and average proctodeal gland area (<400 mm2) laid fertile eggs for a shorter period and had significantly fewer sperm penetration holes than those mated with males having a larger proctodeal gland area (>400 mm2). The proctodeal gland size was positively correlated with testicular weight, plasma testosterone concentrations, and sperm kinetic variables. The results indicate that the size of the proctodeal gland in males can be used to predict sperm function and the duration of fertility in Japanese quail.
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Coturnix , Fertilidad , Interacciones Espermatozoide-Óvulo , Animales , Masculino , Coturnix/fisiología , Coturnix/anatomía & histología , Femenino , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/fisiología , Testículo/fisiología , Testículo/anatomía & histologíaRESUMEN
Sperm mobility (SM) is an objective index for measuring sperm motility; however, the mechanisms underlying its regulation in geese remain unclear. The present study sought to elucidate the genetic mechanism underlying SM traits in Zi geese (Anser cygnoides L.). To this end, three successive experiments were performed. In Experiment I, SM was determined in 40 ganders; the 3 ganders with the highest mobility and three with the lowest mobility were assigned to the high and low sperm mobility rank (SMR) groups, respectively. In Experiment II, the differences in fertility between the two SMR groups were assessed within two breeding flocks comprising the selected six ganders from Experiment I and 30 females (each flock had 3 ganders and 15 females). In Experiment III, the testes of the 6 ganders were harvested for histological observation and whole-transcriptome sequencing. Results revealed better fertility, well-developed seminiferous tubules, and abundant mature sperm in the high-SMR-flock compared to those of the low-SMR-flock (89 vs. 81%) (P < 0.05). Differential expression (DE) analysis identified 76 mRNAs, 344 lncRNAs, and 17 miRNAs between the SMR groups, with LOC106049708, XPNPEP3, GNB3, ADCY8, PRKAG3, oha-miR-182-5p, and ocu-miR-10b-5p identified as key mRNAs and miRNAs contributing to SM. Enrichment analysis implicated these DE RNAs in pathways related to ATP binding, cell metabolism, apelin signaling, Wnt signaling, and Adherens junctions. Additionally, competing endogenous RNA (ceRNA) networks comprising 9 DE mRNAs, 17 DE miRNAs, and 169 DE lncRNAs were constructed. Two ceRNA network pathways (LOC106049708-oha-miR-182-5p-MSTRG.2479.6 and PRKAG3-ocu-miR-10b-5p-MSTRG.9047.14) were identified as key regulators of SM in geese. These findings offer crucial insights into the identification of key genes and ceRNA pathways influencing sperm mobility in geese.
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Gansos , MicroARNs , ARN Largo no Codificante , ARN Mensajero , Motilidad Espermática , Testículo , Animales , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Gansos/genética , Gansos/fisiología , Testículo/metabolismo , Testículo/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Fertilidad/genética , Espermatozoides/fisiologíaRESUMEN
In general snakes show differentiate anatomical, biological and behavioral particularities compared to other species. Basic information about the snakes anatomy, physiology and reproductive biology is scarce in several species, making the reproduction a challenge. Thus, the present work aims to evaluate morphological aspects of the Corallus hortulanus testes, correlating these findings with environmental factors and reproductive aspects. The testes of three specimens of Corallus hortulanus were cut to a thickness of 3µm in microtome, stained with 1% toluidine blue, photo documented and described. Seasonality was observed in the sperm production of Corallus hortulanus, with the presence of mature spermatozoa in the wettest and hottest periods of the year, as well as the largest testicular volume in these periods.
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Estaciones del Año , Testículo , Masculino , Testículo/anatomía & histología , Testículo/fisiología , Animales , Reproducción/fisiología , Espermatozoides/fisiología , Espermatozoides/citología , Colubridae/anatomía & histología , Colubridae/fisiologíaRESUMEN
During the 1890s, animal development became associated with glandular activity, with profound implications for pediatric nosology and treatment. The significance of this endocrinological turn of developmental physiology and pathophysiology in part hinges on an often-overlooked continuity with ubiquitous early modern medical thought concerning semen as a recrementitious (reabsorbed) nutrient or stimulant. Mid-19th-century interests in adult sexual physiology were increasingly nerve-centered and antihumoral. Scattered empirical, particularly veterinarian, interests in gonadal developmental functions failed to moderate these explanatory trends. While Brown-Séquard's rejuvenation experiments still offered no clear starting point for a developmental endocrinology, in 1892 Gaston Variot and Paul Bezançon more explicitly deduced a testicular developmental endocrinological function from various observations on testicular ectopy and a local form of animal "demi-castration." Ensuing interest in the thyroid, the thymus and in the testicles led to various working conceptions of their respective and putatively reciprocal developmental properties, including the idea of a thyroid-testis axis. From 1896, the pubertal affliction of chlorosis became the subject of multiple opotherapeutic approaches, providing an experimental basis for theories of ovarian internal secretion. Polyglandular therapy, piloted for divergent developmental conditions, remained routine until the 1930s despite the biological inefficacy of many endocrine products.
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Endocrinología , Historia del Siglo XIX , Masculino , Animales , Endocrinología/historia , Semen/fisiología , Desarrollo Sexual , Femenino , Humanos , Historia del Siglo XX , Testículo/fisiologíaRESUMEN
Scrotal surface thermography is a non-invasive method for assessing testicular thermoregulation in stallions; however, few studies have explored the application of this technique concerning the thermal physiology of equine reproductive systems. This study aimed to evaluate the consistency of testicular thermoregulation in stallions over a year using thermography to measure the scrotal surface temperature (SST). Moreover, we assessed the best region for measuring the surface body temperature compared with the SST. Ten light-breed stallions were used in the experiment. Thermographic images of the scrotal and body surfaces (neck and abdomen) were captured. Fresh, cooled and frozen-thawed semen samples were evaluated to verify the impact of thermoregulation on semen quality. Testicular thermoregulation was maintained throughout the year in stallions amidst changes in the external temperature, as evidenced by the weak correlation between the SST and ambient temperature. A lower correlation was observed between the environmental temperature and body surface temperature (BTS) obtained from the abdomen (BTS-A; R = .4772; p < .0001) than with that obtained from the neck (BTS-N; R = .7259; p < .0001). Moreover, both BTS-A and SST were simultaneously captured in a single image. The consistent quality of the fresh, cooled and frozen semen suggests efficient thermoregulation in stallions throughout the year.
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Análisis de Semen , Termografía , Animales , Caballos , Masculino , Temperatura , Termografía/veterinaria , Termografía/métodos , Análisis de Semen/veterinaria , Escroto/fisiología , Testículo/fisiología , Semen/fisiologíaRESUMEN
As testicular mesenchymal stromal cells, stem Leydig cells (SLCs) show great promise in the treatment of male hypogonadism. The therapeutic functions of mesenchymal stromal cells are largely determined by their reciprocal regulation by immune responses. However, the immunoregulatory properties of SLCs remain unclear. Here, we observe that SLCs transplantation restore male fertility and testosterone production in an ischemiaâreperfusion injury mouse model. SLCs prevent inflammatory cascades through mitochondrial transfer to macrophages. Reactive oxygen species (ROS) released from activated macrophages inducing mitochondrial transfer from SLCs to macrophages in a transient receptor potential cation channel subfamily member 7 (TRPM7)-mediated manner. Notably, knockdown of TRPM7 in transplanted SLCs compromised therapeutic outcomes in both testicular ischemiaâreperfusion and testicular aging mouse models. These findings reveal a new mechanism of SLCs transplantation that may contribute to preserve testis function in male patients with hypogonadism related to immune disorders.
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Hipogonadismo , Canales Catiónicos TRPM , Humanos , Masculino , Ratones , Animales , Células Intersticiales del Testículo , Testículo/fisiología , Testosterona , Hipogonadismo/terapia , Macrófagos , Proteínas Serina-Treonina QuinasasRESUMEN
The present study evaluated the effects of heat stress on reproductive parameters of hairy rams. Six animals were subjected to scrotal insulation during four consecutive nights (6 PM - 6 AM). Day (D) 0 was the first day of insulation. Scrotal circumference increased from 30.5 ± 0.3â¯cm (at pre-insulation) to 31.8 ± 0.4â¯cm on D4, decreased 3.9â¯cm on D28, returning to 30.6 ± 0.6â¯cm on D57. Sperm concentration decreased from 3.7 ± 0.12 ×109 sperm/mL before insulation to 2.6 ± 0.1 ×109 on D23, returning to normal on D57. Sperm motility averaged 75 ± 2.9% before insulation, was undetectable on D23, and became normal on D77. Sperm with normal morphology reached 5.9 ± 2.6% on D35 but recovered (86.8 ± 2.1%) on D91. Sperm DNA integrity decreased from 86.5 ± 4.7% before insulation to 11.1 ± 3.7% on D63, returning to pre-insulation values on D120. Sperm BSP immunostaining was reduced after scrotal insulation. Variations in seminal protein abundances coincided with changes in sperm parameters. Seminal plasma superoxide dismutase, carboxypeptidase Q-precursor and NPC intracellular cholesterol transporter 2 decreased on D18, returning to normal after D28. Albumin, inhibitor of carbonic anhydrase precursor, EGF-like repeat and discoid I-like domain-containing protein 3 and polymeric immunoglobulin receptor increased after insulation. In summary, intermittent scrotal insulation drastically altered ram sperm attributes and seminal proteins, especially those associated with oxidative stress. Knowledge of animal´s response to thermal stress is vital in the scenario of climate changes.
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Proteoma , Semen , Masculino , Ovinos , Animales , Semen/fisiología , Proteoma/metabolismo , Testículo/fisiología , Motilidad Espermática , Espermatozoides/fisiología , Oveja DomésticaRESUMEN
Semen morphology evaluation in the field should always be performed at 1000× with oil immersion. The development of a spermiogram will aid the practitioner to interpret potential fertility of semen at the time of sampling as well as determine potential causes of an abnormal spermiogram. Bulls, which experience stress or impairment of thermoregulation of the testes for any reason, often experience a transitory decrease in the quality of sperm morphology. This can be recognized by a sequence of appearances of morphologic defects coupled with a thorough patient history.
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Semen , Espermatozoides , Masculino , Bovinos , Animales , Espermatozoides/fisiología , Semen/fisiología , Testículo/anatomía & histología , Testículo/fisiología , Fertilidad/fisiologíaRESUMEN
The histology of blood vessels shows they are structured in three layers or tunics: tunica intima, which includes the internal limiting lamina with high elastin content; tunica media of smooth muscles fibers of circular disposition, which includes the external limiting lamina; and tunica adventitia of connective tissue. The vascular system is essential in regulating body temperature, especially in the scrotum and testis. This study aimed to analyze the histology of the scrotal arteries and their possible relationship to testicular temperature homeostasis. This study used scrotal samples from human adults, anonymized and obtained from the University of Chile's teaching bank. The control group corresponds to an arteriole of muscle tissue. The results show that the middle layer of the scrotal artery is made up of smooth muscle fibers distributed in two layers: a longitudinal inner sublayer and a circular outer sublayer, different from the findings in muscle tissue arteries, with a single, circularly arranged muscle layer. This arrangement could be related to testicular temperature homeostasis by reducing the temperature of the testis and seminiferous tubules. The results described in this work suggest that these anatomical adaptations may be very significant in the face of the constant increase in global temperature. Further and better research is required to understand the mechanisms of thermoregulation in human reproduction and the histological particularities of the tissues that form the scrotum. RESEARCH HIGHLIGHTS: The human scrotal artery has a histological composition adapted for regulation of testicular temperature. The muscular double middle layer of the scrotal artery retains intravascular temperature.
Asunto(s)
Adventicia , Escroto , Masculino , Adulto , Humanos , Escroto/fisiología , Biodiversidad , Temperatura , Testículo/fisiología , Arterias/fisiología , Regulación de la Temperatura Corporal/fisiologíaRESUMEN
Seasonality of reproductive activity in rams and bucks is the major constraint in temperate and subtropical zones. Rapid alternation between 1 month of short days and 1 month of long days (LD) over three years in lightproof buildings eliminates this seasonality. We examined if this would also work in open barns, using only supplementary light. Over two years, one group of bucks (n = 7) was subjected to alternate 1 month of LD and 1 month of permanent light (LD-LL) and another group (n = 7) to alternate 1 month of LD and 1 month of natural light (LD-NL). A simultaneous control group, used for both experiments (CG1, n = 6; CG2, n = 6), remained under natural photoperiod. BW, testis weight (TW), plasma testosterone (T) and cortisol (C) were evaluated in all bucks. CG1 and CG2 bucks showed identical dramatic seasonal variations in BW (stable or decreasing in summer), TW (from 85 ± 12 g in February to 127 ± 7 g in July) and T (from 2.7 ± 1.2 ng/mL in January-April to 24.3 ± 3.2 ng/mL in June-October). By contrast, BW of LD-LL and LD-NL bucks increased regularly during the experiment. From 5 and 9 months after the experiment onset, LD-LL and LD-NL bucks, respectively, maintained constant TW of 115 ± 5 g until the experiment end. After the first 3 months <5 ng/mL, T of LD-LL bucks remained constant (5-10 ng/mL) until the experiment end. By contrast, T of LD-NL bucks showed four periods of low (<5 ng/mL) and two periods of high concentrations (18.1 ± 2.6 and 11.9 ± 3.4 ng/mL). Plasma C remained low (5-8 ng/mL) and did not change with group or light treatment. These results show for the first time in any seasonal photoperiodic species that it is possible to maintain the sexual activity of males all year round in open buildings using alternating periods of LD and LL. By contrast, return to NL instead of LL every other month does not prevent seasonality in T concentration. These results raise interesting questions about the photoperiodic control of neuroendocrine regulation of seasonal sexual activity and suggest that these treatments can be used to manage males in open barns in farms and in artificial insemination centres. (Spanish and French versions of the full text are available as Supplementary Materials S1 and S2).
Asunto(s)
Ritmo Circadiano , Fotoperiodo , Animales , Ovinos , Masculino , Estaciones del Año , Testículo/fisiología , Testosterona , Oveja Doméstica , Cabras/fisiologíaRESUMEN
Studying testicular genes' expression may give key insights into precise regulation of its functions that influence epididymal sperm quality. The current study aimed to investigate the abundance of candidate genes involved in the regulation of testicular functions specially those regulate sperm function (PLA2G4D, SPP1, and CLUAP1), testicular steroidogenic function (ESR1 and AR), materials transport (AQP12B and LCN15), and defense mechanisms (DEFB110, GPX5, SOCS3, and IL6). Therefore, blood samples and testes with epididymis were collected from mature middle-aged (5-10 years) dromedary camels (n = 45) directly prior and after their slaughtering, respectively, during breeding season. Sera were evaluated for testosterone level and testicular biometry was measured with caliper. The epididymal tail semen was evaluated manually. Samples were distinguished based on testosterone level, testicular biometry, as well as epididymal semen features into high and low fertile groups. Total RNA was isolated from testicular tissues and gene expression was done using Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR). Results revealed that testosterone levels were significantly (P < 0.005) higher in camels with good semen quality than those of low quality. There was a significant (P < 0.0001) increase in testicular weight, length, width, thickness, and volume in high fertile than low fertile camels. PLA2G4D, SPP1, CLUAP1, ESR1, AR, AQP12B, LCN15, DEFB110, GPX5, and SOCS3 genes were upregulated (P < 0.001), and IL6 gene was downregulated (P < 0.01) in the testes of high fertile camels compared to the low fertile one. Thus, it could be concluded that examined genes might be valuable monitors of testicular functional status and fertility in dromedary camels.