Hydrohysteroid Dehydrogenases – Biological Role and Clinical Importance – Review

Communications engineering / telecommunication

Loss and recovery of androgen receptor protein expression in the adult rat testis following androgen withdrawal by ethane dimethanesulfonate.

Androgens are especially important for the maintenance of spermatogenesis in adulthood and the experimental withdrawal of testosterone (T) production by ethane dimenthanesulfonate (EDS) is a valuable tool for studying androgen-dependent events of spermatogenesis. The aim of the present study was to investigate the specific changes in immunoexpression of androgen receptor (AR) in the testis in relation to degeneration and regeneration of Leydig cell (LC) population and seminiferous epithelium. Immunohistochemistry for AR and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) as well as TUNEL assay for apoptosis were performed on testicular sections of control and EDS-treated rats. Serum LH and T levels were measured by RIA. Our results revealed a total loss of AR immunoexpression from the nuclei of Sertoli (SCs), LCs and peritubular cells during the first week after EDS administration and that coincided with severe drop in T levels. Two weeks after EDS administration, the AR expression was recovered in these cells but normal stage-specificity in SCs was replaced by uniform intensity of AR immunostaining at all the stages of the spermatogenic cycle. The stage-specific pattern of androgen expression in SCs with a maximum at stages VII-VIII appeared 5 weeks after treatment. LC immunoreactivity for 3beta-HSD at different time points after EDS administration correlated with values of T concentration. The maximal germ cell apoptosis on day 7 was followed by total loss of elongated spermatids 2 weeks after EDS treatment. Regeneration of seminiferous epithelium 3 weeks after EDS administration and onwards occurred in tandem with the development of new LC population indicated by the appearance of 3beta-HSD-positive cells and gradual increase in T production. The specific changes in AR after EDS including their loss and recovery in Sertoli cells paralleled with degenerative and regenerative events in Leydig and germ cell populations, confirming close functional relationship between Sertoli, Leydig and germ cells

The testicular form of angiotensin converting enzyme as a marker for human sperm quality assessment

Introduction: Spermatozoa are rapidly changing cellular structures that are highly dependent on their interaction with the environment. These interactions cause fundamental changes in the spermatozoa’s cells and membrane. All physiological changes that a spermatozoon goes through are required for fertilization. One of the proteins that are essential for the physiological processes in the spermatozoon membrane is the testicular angiotensin-converting enzyme (tACE). In human ejaculated spermatozoa, tACE is found on sperm plasma membrane in the head, neck, and midpiece of the tail having an active role in the capacitation and acrosome reaction. Aim: Immuno-histochemical and fluorescent testing of the testicular isoform of the angiotensin-converting enzyme during spermiogenesis and acrosome membrane of spermatozoa. Materials and methods: Testis biopsies from infertile males have used immunohistochemical testing and fixed spermatozoa for the immunofluorescence assay of tACE. Results: The immunohistochemical test showed tACE expression during spermiogenesis and its participation in the stages of spermatid differentiation in the testis. The immunofluorescent test follows the manifestation of tACE in untreated, capacitated, and acrosome-reacting spermatozoa. In the process of capacitation and acrosome reaction, we found considerable dynamics accompanied by a change in the expression of tACE on the sperm membrane. Conclusions: tACE expression during spermiogenesis and its visualization in the acrosome region confirms the active role of the enzyme in the processes of maturation, capacitation, and acrosome reaction, which determines the enzyme as a reliable marker for the selection of quality spermatozoa in assisted reproduction

Chapter Hydrohysteroid Dehydrogenases – Biological Role and Clinical Importance – Review

Communications engineering / telecommunication

Stage specific expression of angiotensin-converting enzyme and thickened lamina propria in relation to male fertility

Introduction: The testis is an immune privileged organ that provides a specific environment for germ cell development. Various factors responsible for inflammatory changes can lead to deterioration of the immune tolerant model found in the testis. As a result, the thickness of the proper membrane of seminiferous tubules changes and the process of spermatogenesis is disturbed. Aim: The purpose of the present study was to find the connection between the changes in the level of testis-specific isoform of angiotensin-converting enzyme (tACE) expression and the morphological changes of the seminiferous tubule wall of the testis in patients with infertility. Materials and methods: The study included 24 infertile men who underwent a testicular biopsy. Routine histological techniques, immunohistochemical reactions for tACE, α-smooth muscle actin, and morphometric analysis were performed to examine the biopsy preparations. Results: By using testicular biopsy to diagnose patients with infertility, a stage-specific pattern of the processes associated with thickened proper membrane of seminiferous tubules was established and a decreased or absent spermatogenic activity was observed. Conclusions: A significant increase in the proper membrane thickness of the seminiferous tubules in the testis was found in patients with infertility. This finding shows that the processes take place gradually over time, correlating with the degree of pathology, and that changes do not depend on the factors causing them. We also found that the degree of proper membrane thickening correlated with disturbances of spermatogenesis, using tACE expression as a marker for spermatogenic epithelium differentiation

Experimental Investigations. Neurotrophic Factor Receptors trkB and trkC in Experimental Model of Lesion in Rat Brain Structures in Schizophrenia / Рецепторы Нейротрофических Факторов trkB И trkC В Эксперимен- Тальной Модели Для Исследования Повреждений В Мозговых Структурах Крысы При Шизофрении

ВВЕДЕНИЕ: Модель шизофрении, связанной с нарушениями в развитии постулирует патологические отклонения в эмбриональном нейрогенезе в качестве этиопатогенетической основы шизофренических психозов. Гипотеза о нейротрофических факторах объясняет данные нейропатологические отклонения как результат нарушений в системе нейротрофинов, вызванных различными генетическими, инфекциозными и травматическими факторами. Тирозинкиназные рецепторы trkB и trkC опосредуют эффекты нейротрофинов, стимулирующих рост и соответствуют изменениям в их наличности. ЦЕЛЬ: Целью настоящего исследования является установление модели экспрессии trkB и trkC в мозговых структурах крысы при экспериментальной модели шизофрении. МАТЕРИАЛЫ И МЕТОДЫ: На криостатных срезах мозга контрольных и испытуемых крыс (после билатеральной инфузии изибутановой кислоты в гиппокампальную формацию) была прослежена иммунореактивность на trkB и trkC. РЕЗУЛЬТАТЫ: Наш анализ выявил заниженную экспрессию рецепторов trkB и trkC в гиппокампальной формации испытуемых животных по сравнению с контрольными. Количественное измерение интенсивности иммуногистохимических реакций и статистический анализ подтвердили понижение иммунореактивности исследуемых антигенов (trkB и trkC) в позитивных гиппокампальных нейронах у испытуемых крыс 56-дневного возраста по сравнению с иммунореактивностью контрольных животных. ЗАКЛЮЧЕНИЕ: Установленное понижение в экспрессии рецепторов нейротрофических факторов можно рассматривать в связи с нарушением функции и пластичности гиппокампальной формации в мозге при шизофрении

The testicular form of angiotensin converting enzyme as a marker for human sperm quality assessment

Introduction: Spermatozoa are rapidly changing cellular structures that are highly dependent on their interaction with the environment. These interactions cause fundamental changes in the spermatozoa’s cells and membrane. All physiological changes that a spermatozoon goes through are required for fertilization. One of the proteins that are essential for the physiological processes in the spermatozoon membrane is the testicular angiotensin-converting enzyme (tACE). In human ejaculated spermatozoa, tACE is found on sperm plasma membrane in the head, neck, and midpiece of the tail having an active role in the capacitation and acrosome reaction. Aim: Immuno-histochemical and fluorescent testing of the testicular isoform of the angiotensin-converting enzyme during spermiogenesis and acrosome membrane of spermatozoa. Materials and methods: Testis biopsies from infertile males have used immunohistochemical testing and fixed spermatozoa for the immunofluorescence assay of tACE. Results: The immunohistochemical test showed tACE expression during spermiogenesis and its participation in the stages of spermatid differentiation in the testis. The immunofluorescent test follows the manifestation of tACE in untreated, capacitated, and acrosome-reacting spermatozoa. In the process of capacitation and acrosome reaction, we found considerable dynamics accompanied by a change in the expression of tACE on the sperm membrane. Conclusions: tACE expression during spermiogenesis and its visualization in the acrosome region confirms the active role of the enzyme in the processes of maturation, capacitation, and acrosome reaction, which determines the enzyme as a reliable marker for the selection of quality spermatozoa in assisted reproduction

11beta-hydroxysteroid dehydrogenase type 2 expression in the newly formed Leydig cells after ethane dimethanesulphonate treatment of adult rats.

The enzyme 11beta-hydroxysteroid dehydrogenase (11beta-HSD) catalyzes the reversible conversion of physiologically active corticosterone to the biologically inert 11beta-dehydrocorticosterone in rat testis and protect the Leydig cells (LCs) against the suppressive effect of glucocorticoids. The developmental pathway of the adult LCs population is accompanied with an increase in the 11beta-HDS activity. Thus, 11beta-HDS together with its role in controlling the toxicological effect of glucocorticoids on LCs can be used as a marker for their functional maturity. Ethane 1,2-dimethanesulphonate (EDS) treatment of adult rats become unique appropriate model, which enable to answer many questions related to the differentiation of adult LCs in the prepubertal rat testis. The aim of the present study was to investigate the specific changes in the 11beta-HDS type 2 immunoreactivity in tandem with the expression of androgen receptor (AR) during renewal of LCs population after EDS treatment. In the present study, we observed the first appearance of immunostaining for 11beta-HSD2 in new LCs population on day 14 after EDS administration when the progenitor LCs were detected. Our immunohistochemical analysis revealed progressive increases in the 11beta-HSD2 reaction intensity on 21 days after EDS treatment and reached a maximum on day 35. AR immunoexpression was found in new LCs on day 14 and 21 after EDS injection with an increasing curve of intensity. The most prominent AR immunostaining in new population LCs was evident by 35 days after EDS and that coincided with the increased number of LCs and restoration of adult LCs population. Our results demonstrated similar pattern of immunoreactivity for 11beta-HSD2 and AR in new LCs population after EDS treatment and suggested that the changes in 11beta-HSD2 expression can be used for evaluation of adult LCs differentiation in rat testis

Age-related changes in the expression of 11beta-hydroxysteroid dehydrogenase type 2 in rat Leydig cells.

Previous studies in rats have shown that the ability of Leydig cells (LCs) to produce testosterone significantly declines with age. To address the possible mechanisms by which aging LCs lose their steroidogenic function, we determined the effect of aging on the expression of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) type 2. The enzyme plays a protective role in blunting the suppressive effects of glucocorticoids on LCs steroidogenesis. Our immunohistochemical analysis revealed progressive decline in 11beta-HDS type 2 expression in LCs of the 18 months of age rats and the most significant reduction in 11beta-HSD2 immunoreactivity was evident in the testicular interstitium of 24- month-old rats. The decrease in the 11beta-HDS type 2 immunostaining in LCs during aging coincided with decline in insulin-like 3/relaxin-like factor (INSL3/RLF) expression, an independent marker for LCs differentiation status. Concomitant with the age-related decrease of 11beta-HDS type 2 immunoreactivity in the LCs population, the immunoexpression of 3beta-hydroxysteroid dehydrogenase (3beta-HSD), marker for LCs steroidogenic activity, was greatly reduced at 24 months compared to 3-month-old control. Similar pattern of expression exhibited also androgen receptor (AR) which is localized in the nuclei of Sertoli cells (SCs), LCs, and peritubular cells. During ages we observed progressive decrease in the immunoreactivity for AR in the testicular types and there was a loss of stage specificity in SCs at age of 24 months. It now seems evident that a variety of factors are likely to be involved in age-related decreases in LCs steroidogenesis, including 11beta-HSD type 2. The observed reduction in 11beta-HSD type 2 expression in aging LCs reflects the decline in their protection ability, opposing the suppressive effect of glucocorticoids on testosterone production