Male animal sterilization: history, current practices, and potential methods for replacing castration.

Sterilization and castration have been synonyms for thousands of years. Making an animal sterile meant to render them incapable of producing offspring. Castration or the physical removal of the testes was discovered to be the most simple but reliable method for managing reproduction and sexual behavior in the male. Today, there continues to be global utilization of castration in domestic animals. More than six hundred million pigs are castrated every year, and surgical removal of testes in dogs and cats is a routine practice in veterinary medicine. However, modern biological research has extended the meaning of sterilization to include methods that spare testis removal and involve a variety of options, from chemical castration and immunocastration to various methods of vasectomy. This review begins with the history of sterilization, showing a direct link between its practice in man and animals. Then, it traces the evolution of concepts for inducing sterility, where research has overlapped with basic studies of reproductive hormones and the discovery of testicular toxicants, some of which serve as sterilizing agents in rodent pests. Finally, the most recent efforts to use the immune system and gene editing to block hormonal stimulation of testis function are discussed. As we respond to the crisis of animal overpopulation and strive for better animal welfare, these novel methods provide optimism for replacing surgical castration in some species.

PTBP1 mediates Sertoli cell actin cytoskeleton organization by regulating alternative splicing of actin regulators.

Spermatogenesis is a biological process within the testis that produces haploid spermatozoa for the continuity of species. Sertoli cells are somatic cells in the seminiferous epithelium that orchestrate spermatogenesis. Cyclic reorganization of Sertoli cell actin cytoskeleton is vital for spermatogenesis, but the underlying mechanism remains largely unclear. Here, we report that RNA-binding protein PTBP1 controls Sertoli cell actin cytoskeleton reorganization by programming alternative splicing of actin cytoskeleton regulators. This splicing control enables ectoplasmic specializations, the actin-based adhesion junctions, to maintain the blood-testis barrier and support spermatid transport and transformation. Particularly, we show that PTBP1 promotes actin bundle formation by repressing the inclusion of exon 14 of Tnik, a kinase present at the ectoplasmic specialization. Our results thus reveal a novel mechanism wherein Sertoli cell actin cytoskeleton dynamics is controlled post-transcriptionally by utilizing functionally distinct isoforms of actin regulatory proteins, and PTBP1 is a critical regulatory factor in generating such isoforms.

Cryptorchidism and testicular cancer in the dog: unresolved questions and challenges in translating insights from human studies†.

Cryptorchidism, the failure of one or both testes to descend into the scrotum, and testicular cancer show a strong correlation in both dogs and humans. Yet, long-standing medical debates persist about whether the location of undescended testes directly causes testicular cancer in humans or if both conditions stem from a common origin. Although testicular cancer is a prevalent disease in dogs, even less is known about its cause and correlation with testicular descent in this species. This review investigates the relation between these two disorders in dogs, drawing insights from human studies, and examines key biomarkers identified thus far. In addition, it explores potential causal links, including the impact of temperature on maturing testicular cells and a potential shared genetic origin. Notably, this literature review reveals significant differences between men and dogs in reproductive development, histological and molecular features of testicular tumors, and the prevalence of specific tumor types, such as Sertoli cell tumors in cryptorchid dogs and germ cell tumors in humans. These disparities caution against using dogs as models for human testicular cancer research and underscore the limitations when drawing comparisons between species. The paper concludes by suggesting specific research initiatives to enhance our understanding of the complex interplay between cryptorchidism and testicular cancer in dogs.

Prenatal exposure to Di(2-ethylhexyl) phthalate and high-fat diet synergistically disrupts gonadal function in male mice†.

Prenatal exposure to Di (2-ethylhexyl) phthalate (DEHP) impairs the reproductive system and causes fertility defects in male offspring. Additionally, high-fat (HF) diet is a risk factor for reproductive disorders in males. In this study, we tested the hypothesis that prenatal exposure to a physiologically relevant dose of DEHP in conjunction with HF diet synergistically impacts reproductive function and fertility in male offspring. Female mice were fed a control or HF diet 7 days prior to mating and until their litters were weaned on postnatal day 21. Pregnant dams were exposed to DEHP or vehicle from gestational day 10.5 until birth. The male offspring's gross phenotype, sperm quality, serum hormonal levels, testicular histopathology, and testicular gene expression pattern were analyzed. Male mice born to dams exposed to DEHP + HF had smaller testes, epididymides, and shorter anogenital distance compared with those exposed to HF or DEHP alone. DEHP + HF mice had lower sperm concentration and motility compared with DEHP mice. Moreover, DEHP + HF mice had more apoptotic germ cells, fewer Leydig cells, and lower serum testosterone levels than DEHP mice. Furthermore, testicular mRNA expression of Dnmt1 and Dnmt3a was two to eight-fold higher than in DEHP mice by qPCR, suggesting that maternal HF diet and prenatal DEHP exposure additively impact gonadal function by altering the degree of DNA methylation in the testis. These results suggest that the combined exposure to DEHP and high-fat synergistically impairs reproductive function in male offspring, greater than exposure to DEHP or HF diet alone.

GEPRO: Gene Expression Profiler for DNA microarray data / GEPRO: Analizador de Expresión Genética para datos provenientes demicroarreglos de DNA / GEPRO: Analisador de Expressão Gênica para dados provenientes de microarranjosde DNA

The DNA microarray technology has been widely employed in recent biological research. However,the unprecedented large amount of data produced by the technology has presented inevitable challengesto biological scientists, forcing individual researchers to take extensive training or rely on databasespecialists for the use of the data. Microsoft Excel® has a number of convenient functions and may be themost widely used spreadsheet package for data storage and manipulation. Therefore, we developed a userfriendly,Excel spreadsheet-based microarray data-managing program. The program, gene expressionprofiler (GEPRO), is designed to facilitate organizing miocroarray data, performing statistical analysis,and displaying the results. Using GEPRO’s filtering and sorting capabilities, a user can easily identifydifferentially expressed genes, display the expression profiles of the genes of interest, and present andsave the analyzed data in a user-defined way. The versatility and utility of GEPRO should enable benchwork researchers to maximize the use of their microarray data. The GEPRO is freely available for noncommercialusers at http://www.mc.uky.edu/cls/ko/gepro1.html.

La tecnología de microarreglos de DNA es actualmente empleada de manera amplia en investigaciónbiológica. Sin embargo, el manejo de la enorme cantidad de datos generados por la misma representa un desafió para los investigadores, forzándolos a invertir valioso tiempo en capacitación sobre dicho manejo, o aconfiar el uso de la misma a especialistas en bases de datos. El programa Excel® de Microsoft, la hoja de calculomas ampliamente utilizada a nivel mundial, que cuenta con muchas funciones útiles para almacenamiento ymanipulación de datos, fue utilizado por nosotros para desarrollar una aplicación amigable para el manejode datos generados por microarreglos de DNA. Nuestro programa, llamado “Gene Expression Profiler”(GEPRO), esta diseñado para facilitar la organización de datos de microarreglos, realizar su análisisestadístico, y presentar los resultados. Utilizando la posibilidad de filtrado y ordenamiento de datos queofrece GEPRO, el usuario puede identificar fácilmente diferentes genes, observar los perfiles de expresión delos genes de interés, así como presentar y guardar los datos de diversas maneras. La versatilidad y utilidad deGEPRO ayuda a los investigadores a maximizar la utilización de sus datos de microarreglos. GEPRO es unaaplicación gratuita, disponible para uso no comercial en http://www.mc.uky.edu/cls/ko/gepro1.html.

A Tecnologia dos Mircroarranjos de DNA é muito empregada em pesquisa biológica. Mas o manejo dagrande quantidade de dados gerados é um desafio para os pesquisadores, os quais estão sendo forçados arealizar grandes investimentos econômicos e de tempo para sua capacitação ou em confiar em expertos dainformática para analisar seus dados. O programa Excel® da Microsoft, amplamente utilizada no mundofoi utilizado para desenvolver uma aplicação amigável para o manejo de dados gerados por Mircroarranjosde DNA. O nosso programa, chamado “Gene Expression Profiler” (GEPRO), está desenhado para facilitara organização de dados, permite realizar as respectivas análises estatísticas e apresentar os resultados.Utilizando a possibilidade de filtrar e organizar os dados que oferece GEPRO, o usuário pode identificarpares de genes, observarem os perfis da expressão dos genes de interesse, assim como a possibilidadede apresentar e salvar os dados de diferentes formas. A versatilidade e a utilidade do programa, ajudaaos pesquisadores a maximizar a utilização dos dados. GEPRO é uma aplicação gratuita para uso nãocomercial, disponível em http://www.mc.uky.edu/cls/ko/gepro1.html.