The gut microbiota and developmental programming of the testis in mice

Nutrients and environmental chemicals, including endocrine disruptors, have been incriminated in the current increase in male reproductive dysfunction, but the underlying mechanisms remain unknown. The gastrointestinal tract represents the largest surface area exposed to our environment and thereby plays a key role in connection with exposure of internal organs to exogenous factors. In this context the gut microbiome (all bacteria and their metabolites) have been shown to be important contributors to body physiology including metabolism, cognitive functions and immunity. Pivotal to male reproduction is a proper development of the testis, including the formation of the blood-testis barrier (BTB) that encapsulates and protects germ cells from stress induced environmental cues, e.g. pathogenic organisms and xenobiotics. Here we used specific pathogen free (SPF) mice and germ-free (GF) mice to explore whether gut microbiota and/or their metabolites can influence testis development and regulation of BTB. Lumen formation in the seminiferous tubules, which coincides with the development of the BTB was delayed in the testes of GF mice at 16 days postpartum. In addition, perfusion experiments (Evans blue) demonstrated increased BTB permeability in these same mice. Reduced expressions of occludin, ZO-2 and E-cadherin in GF testis suggested that the microbiota modulated BTB permeability by regulation of cell-cell adhesion. Interestingly, exposure of GF mice to Clostridium Tyrobutyricum (CBUT), which secrete high levels of butyrate, restored the integrity of the BTB and normalized the levels of cell adhesion proteins. Moreover, the GF mice exhibited lower serum levels of gonadotropins (LH and FSH) than the SPF group. In addition, the intratesticular content of testosterone was lower in GF compared to SPF or CBUT animals. Thus, the gut microbiome can modulate the permeability of the BTB and might play a role in the regulation of endocrine functions of the testis.Scopu

Bortezomib treatment causes long-term testicular dysfunction in young male mice

Peer reviewe

Nash-wo-Numa (childhood growth & development) study protocol: Factors that impact linear growth in children 9 to 15 years of age in Matiari, Pakistan

Introduction: Adolescence is a time of significant physical and emotional change, and there is emerging concern that adolescents living in low- and middle-income countries (LMIC) may face substantial challenges in relation to linear growth and mental health. Data on the global burden of stunting after 5 years of age are limited, but estimates suggest up to 50 per cent of all adolescents in some LMIC are stunted. Additionally, many LMIC lack robust mental health care delivery systems. Pakistan has one of the world\u27s largest populations of adolescents (10 to 19 years) at approximately 40 million. The Nash-wo-Numa study\u27s primary objective is to assess the prevalence and risk factors for stunting among early adolescents in rural Pakistan. The study also aims to determine the prevalence of poor mental health and identify factors associated with common mental health concerns during the childhood to adulthood transition.Methods: This cross-sectional study will include girls (n= 738) 9.0 to 14.9 years of age and boys (n=687) 10.0 to 15.9 years of age who live in the rural district of Matiari, Pakistan. Participants will be assessed for anthropometrical measures, puberty development, nutritional biomarkers as well as symptoms of depression, anxiety and trauma using validated scales.Ethics and Dissemination: The proposed study aims to complete the picture of child and adolescent health concerning linear growth and mental health by including puberty indicators. Ethics approval has been granted by the Ethics Review Committee at the Aga Khan University, Karachi, Pakistan, #5251-WCH-ERC-18 and Research Ethics Board at SickKids Hospital, Toronto, Canada, #:1000060684. Study results will be presented at relevant conferences and published in peer-reviewed journals

Novel associations in disorders of sex development: findings from the I-DSD registry

Context: The focus of care in disorders of sex development (DSD) is often directed to issues related to sex and gender development. In addition, the molecular etiology remains unclear in the majority of cases.<p></p> Objective: To report the range of associated conditions identified in the international DSD (I-DSD) Registry.<p></p> Design, Setting, and Patients: Anonymized data were extracted from the I-DSD Registry for diagnosis, karyotype, sex of rearing, genetic investigations, and associated anomalies. If necessary, clarification was sought from the reporting clinician.<p></p> Results: Of 649 accessible cases, associated conditions occurred in 168 (26%); 103 (61%) cases had one condition, 31 (18%) had two conditions, 20 (12%) had three conditions, and 14 (8%) had four or more conditions. Karyotypes with most frequently reported associations included 45,X with 6 of 8 affected cases (75%), 45,X/46,XY with 19 of 42 cases (45%), 46,XY with 112 of 460 cases (24%), and 46,XX with 27 of 121 cases (22%). In the 112 cases of 46,XY DSD, the commonest conditions included small for gestational age in 26 (23%), cardiac anomalies in 22 (20%), and central nervous system disorders in 22 (20%), whereas in the 27 cases of 46,XX DSD, skeletal and renal anomalies were commonest at 12 (44%) and 8 (30%), respectively. Of 170 cases of suspected androgen insensitivity syndrome, 19 (11%) had reported anomalies and 9 of these had confirmed androgen receptor mutations.<p></p> Conclusions: Over a quarter of the cases in the I-DSD Registry have an additional condition. These associations can direct investigators toward novel genetic etiology and also highlight the need for more holistic care of the affected person.<p></p&gt

Novel associations in disorders of sex development: findings from the I-DSD registry

Context: The focus of care in disorders of sex development (DSD) is often directed to issues related to sex and gender development. In addition, the molecular etiology remains unclear in the majority of cases.<p></p> Objective: To report the range of associated conditions identified in the international DSD (I-DSD) Registry.<p></p> Design, Setting, and Patients: Anonymized data were extracted from the I-DSD Registry for diagnosis, karyotype, sex of rearing, genetic investigations, and associated anomalies. If necessary, clarification was sought from the reporting clinician.<p></p> Results: Of 649 accessible cases, associated conditions occurred in 168 (26%); 103 (61%) cases had one condition, 31 (18%) had two conditions, 20 (12%) had three conditions, and 14 (8%) had four or more conditions. Karyotypes with most frequently reported associations included 45,X with 6 of 8 affected cases (75%), 45,X/46,XY with 19 of 42 cases (45%), 46,XY with 112 of 460 cases (24%), and 46,XX with 27 of 121 cases (22%). In the 112 cases of 46,XY DSD, the commonest conditions included small for gestational age in 26 (23%), cardiac anomalies in 22 (20%), and central nervous system disorders in 22 (20%), whereas in the 27 cases of 46,XX DSD, skeletal and renal anomalies were commonest at 12 (44%) and 8 (30%), respectively. Of 170 cases of suspected androgen insensitivity syndrome, 19 (11%) had reported anomalies and 9 of these had confirmed androgen receptor mutations.<p></p> Conclusions: Over a quarter of the cases in the I-DSD Registry have an additional condition. These associations can direct investigators toward novel genetic etiology and also highlight the need for more holistic care of the affected person.<p></p&gt

Role of testicular interleukin-1alpha tIL-1alpha in testicular physiology and disease

This review focuses on the role of the cytokine interleukin-1alpha (IL-1alpha) in the testis; elaborating upon its importance during the complex process of spermatogenesis while relating this cytokine to some of the pathophysiological states affecting the testis. IL-1alpha, a proinflammatory cytokine, is expressed constitutively by the intact adult rat testis where it acts on germ, Sertoli and Leydig cells to regulate germ cell proliferation and steroidogenesis. The sequence identity of testicular IL-1alpha matches with the one secreted by activated macrophages in systemic immunity. The classical macrophage IL-1alpha is produced as 32 kDa precursor protein which is processed to mature 17 kDa IL-1alpha and a 16 kDa propiece. The rat testicular IL-1alpha, mainly secreted by Sertoli cells, was found to have molecular heterogeneity that can be observed both at the transcriptional and the translational levels. In the rat testis, two transcripts were found to be expressed with 941 bp and 767 bp (that lacks 174 bp) which were translated into 32 kDa and 24 kDa precursor proteins, respectively. The 32 kDa precursor protein is processed to the 17 kDa mature IL-1alpha. Identical transcripts are also shown to be present in cat, dog and pig. Most of the functional role is assigned to the mature 17 kDa IL-1alpha isoform. However, functional analysis of recombinant rat IL-1alpha isoforms showed that there was a clear biopotency difference between these forms in order of 17 kDa IL-1alpha\u3e32proIL-1alpha\u3e24proIL-1alpha. Furthermore, the mature 17 kDa tIL-1alpha has also been implicated in pathologies such as orchitis, relapse of acute lymphoblastic leukemia (ALL) in the testis and infertility disorders in men. Thus, tIL-1alpha may play an important functional role both in coordination of normal testicular physiology as well as in contributing to the disease states in the testis

Placental IGF-I, IGFBP-1, zinc, and iron, and maternal and infant anthropometry at birth

Aim:To correlate placental protein levels of insulin-like growth factor (IGF)-I and insulin-like growth factor binding protein (IGFBP)-1, with previously determined levels of IGF-I and IGF-II mRNA expression, and the micronutrients zinc and iron, and maternal and newborn anthropometry. Methods: Placental samples were collected from rural field sites in Pakistan. Samples were divided into small and large for gestational age groups (SGA and LGA, respectively). IGFBP-1 levels were assessed using Western immunoblotting. IGF-I protein levels were assessed using ELISA techniques. IGF mRNA expression, zinc, and iron, were quantified as previously described and were used for comparative Purposes only. Results: Thirty-three subjects were included (SGA, n = 12, LGA n = 21). Higher levels of IGFBP-1 were seen in the SGA group (p \u3c 0.01). IGFBP-1 correlated positively with maternal and infant triceps skin-fold thickness in the LGA and SGA groups, respectively (p \u3c 0.05). Significantly lower IGF-I protein levels were seen in the SGA group. IGF-I levels correlated significantly with maternal and newborn anthropometry. IGFBP-1 correlated significantly with IGF-II mRNA expression (p \u3c 0.05). Conclusion: Placental protein levels of IGF-I and IGFBP-1 appear to be associated with maternal anthropometry. Maternal anthropometry may thus influence IGFBP-1 and IGF-I levels and may possibly be used for screening of pregnancies, with the potential for timely identification of these high-risk pregnancies

A rapid method of Sertoli cell isolation by DSA lectin, allowing mitotic analyses

We have developed a rapid and convenient method of Sertoli cell preparation for studying the growth kinetics of these cells in in vitro culture. Datura Stramonium agglutinin (DSA)-coated dishes were used to rapidly purify single Sertoli cells from immature rat testis. We have monitored by immunohistochemical markers the degree of contamination of our Sertoli cell preparation by other cell types. The cell preparation is essentially free of germ cells and interstitial cells and contains a minimal percentage of myoid cells. Sertoli cells isolated with this method retain functional activities such as the FSH responsiveness in terms of cAMP production. In addition, we have studied the proliferative activity of Sertoli cells isolated by lectin binding from rats of different ages. Sertoli cells exhibited a characteristic pattern of proliferation which was a function of the donor animal age. The proliferative activity of isolated Sertoli cells decreased with age, being much higher in 3 day-old rats than in older animals. A similar pattern was observed when the mitotic activity of Sertoli cells in response to mitogens present in the testicular extracts from 5 day-old rats was evaluated. The method described here reduces or eliminates many of the drawbacks of the conventional procedures used to isolate Sertoli cells, thus providing a useful tool in studies of growth kinetics and regulation of cell proliferation in vitro. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved