Exploring the Role of Estrogens in Lizard Spermatogenesis through the Study of Clomiphene and FSH Effects

International Journal of Endocrinology ◽

10.1155/2017/4760638 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Mariailaria Verderame ◽

Rosaria Scudiero ◽

Ermelinda Limatola

Keyword(s):

Natural Condition ◽

Biological Process ◽

Clomiphene Citrate ◽

Active Role ◽

Sex Hormone ◽

Podarcis Sicula ◽

Mating Period ◽

Agonist And Antagonist ◽

Experimental Approaches

Spermatogenesis is a fascinating biological process aiming to generate haploid spermatozoa from diploid spermatogonia through a specific hormonal network between gonadotropins and steroids. Increasing evidence suggests that the primary female sex hormone estrogen plays an active role in this process. This research points out on the role of estrogen during lizard spermatogenesis by using three experimental approaches: (1) exposure to an analogue of nonsteroidal estrogen as Clomiphene citrate that acts both as estrogen agonist and antagonist; (2) exposure to the gonadotropin FSH; and (3) exposures to FSH followed by Clomiphene. Histological and immunohistochemical results demonstrate that in the lizard Podarcis sicula during the mating period, Clomiphene as well as FSH determines the breakdown of spermatogenesis and the epididymal regression, presumably through estrogens input as indirectly demonstrated by the appearance of ERα and vitellogenin in the liver. The ability of Clomiphene to restore the gonadal natural condition after FSH treatment is also demonstrated. Finally, data indicate that lizard testis and epididymis control their morphophysiology regulating the intracellular presence of ERα.

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Natural Compounds in Sex Hormone-Dependent Cancers: The Role of Triterpenes as Therapeutic Agents

Frontiers in Endocrinology ◽

10.3389/fendo.2020.612396 ◽

2021 ◽

Vol 11 ◽

Author(s):

Codruţa Şoica ◽

Mirela Voicu ◽

Roxana Ghiulai ◽

Cristina Dehelean ◽

Roxana Racoviceanu ◽

...

Keyword(s):

Molecular Mechanisms ◽

Therapeutic Potential ◽

Treatment Options ◽

Active Role ◽

Structural Features ◽

Sex Hormone ◽

Ongoing Research ◽

New Treatment ◽

Highly Correlated

Sex hormone-dependent cancers currently contribute to the high number of cancer-related deaths worldwide. The study and elucidation of the molecular mechanisms underlying the progression of these tumors was a double-edged sword, leading to the expansion and development of new treatment options, with the cost of triggering more aggressive, therapy resistant relapses. The interaction of androgen, estrogen and progesterone hormones with specific receptors (AR, ER, PR) has emerged as a key player in the development and progression of breast, ovarian, prostate and endometrium cancers. Sex hormone-dependent cancers share a common and rather unique carcinogenesis mechanism involving the active role of endogenous and exogenous sex hormones to maintain high mitotic rates and increased cell proliferation thus increasing the probability of aberrant gene occurrence and accumulation highly correlated with abnormal cell division and the occurrence of malignant phenotypes. Cancer related hormone therapy has evolved, currently being associated with the blockade of other signaling pathways often associated with carcinogenesis and tumor progression in cancers, with promising results. However, despite the established developments, there are still several shortcomings to be addressed. Triterpenes are natural occurring secondary metabolites biosynthesized by various pathways starting from squalene cyclization. Due to their versatile therapeutic potential, including the extensively researched antiproliferative effect, these compounds are most definitely a cornerstone in the research and development of new natural/semisynthetic anticancer therapies. The present work thoroughly describes the ongoing research related to the antitumor activity of triterpenes in sex hormone-dependent cancers. Also, the current review highlights both the biological activity of various triterpenoid compounds and their featured mechanisms of action correlated with important chemical structural features.

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Spermatogenic Waves and Expression of AR and ERs in Germ Cells ofPodarcis sicula

International Journal of Zoology ◽

10.1155/2014/965617 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Mariailaria Verderame ◽

Francesco Angelini ◽

Ermelinda Limatola

Keyword(s):

Germ Cells ◽

Late Summer ◽

Early Summer ◽

Podarcis Sicula ◽

Mating Period ◽

Late Pachytene ◽

Seasonal Breeder ◽

Almost All

Androgens are considered the main hormones that regulate spermatogenesis, but a lot of evidence confers to estrogen a key role in this process. In the testis of the seasonal breeder lizardPodarcis siculawe analyzed by means ofin situhybridization the expression of the androgen receptor (AR) and of the two types,αandβ, of the estrogen receptors (ERs) throughout the three periods of the annual cycle: mating (spring-early summer), postmating-refractory (late summer), and autumnal recrudescence. The results show that during the mating period AR and ERs are expressed in all germ cells present in the tubules from spermatogonia to spermatozoa. During the postmating-refractory period, when only spermatogonia are present in the tubules, almost all express ERs and very few AR mRNA. During the autumnal recrudescence the localization of AR and ERs is the same of the mating period except for the population of the primary spermatocytes. The expression of the investigated receptors is peculiar in these cells that are positive in the middle-late pachytene stage of the meiotic prophase and negative in preleptotene. A possible functional role of the observed differences during spermatogenesis and in the spermatozoa is also discussed.

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The Involvement of the Androgen Receptor in the Secretion of the Epididymalcorpusin the LizardPodarcis sicula

International Journal of Zoology ◽

10.1155/2014/457830 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Mariailaria Verderame

Keyword(s):

Androgen Receptor ◽

Estrogen Receptors ◽

Expression Pattern ◽

Crucial Role ◽

Secretory Activity ◽

Seasonal Breeding ◽

Podarcis Sicula ◽

Mating Period

A crucial role in the maintenance of male reproductive functions is carried out by the androgen through its receptor in balance with the estrogen receptors (ERs). The distribution of the androgen receptor (AR) is well documented in the testis and in the reproductive tissues of mammals but the findings about the AR in nonmammalian vertebrates and in particular in reptiles are very scarce. Here by means ofin situhybridization (ISH) we investigated the AR expression along the epididymal channel (efferent ductules,corpus, andcauda) ofPodarcis siculaduring the mating and nonmating period. The results show that in this seasonal breeding species the AR expression pattern is always constant throughout the epididymis. The administration of estradiol-17βin the mating period does not affect the AR expression but inhibits the secretory activity of the epididymalcorpus. To verify the expression pattern of ERs, we also conducted ISH investigations on adjacent sections with ERs probes. The findings suggest that AR induces the secretory activity in the epithelial cells of the epididymalcorpusand confirm our previous results that showed the role of ERalpha (ERα) as switch off for the secretion of this compartment.

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Role of spectrin in membrane fusion and in shape change of human erythrocyte ghost

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082509 ◽

1978 ◽

Vol 36 (2) ◽

pp. 328-329

Author(s):

Hideo Hayashi ◽

Yoshikazu Hirai ◽

John T. Penniston

Keyword(s):

Conformational Changes ◽

Human Erythrocyte ◽

Shape Change ◽

Membrane Surface ◽

Slight Modification ◽

Active Role ◽

Main Role ◽

Bank Blood ◽

Human Erythrocyte Ghost

Spectrin is a membrane associated protein most of which properties have been tentatively elucidated. A main role of the protein has been assumed to give a supporting structure to inside of the membrane. As reported previously, however, the isolated spectrin molecule underwent self assemble to form such as fibrous, meshwork, dispersed or aggregated arrangements depending upon the buffer suspended and was suggested to play an active role in the membrane conformational changes. In this study, the role of spectrin and actin was examined in terms of the molecular arrangements on the erythrocyte membrane surface with correlation to the functional states of the ghosts.Human erythrocyte ghosts were prepared from either freshly drawn or stocked bank blood by the method of Dodge et al with a slight modification as described before. Anti-spectrin antibody was raised against rabbit by injection of purified spectrin and partially purified.

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Elucidation of block boundaries as the dissolution channels in hydrated cement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109562 ◽

1978 ◽

Vol 36 (1) ◽

pp. 484-485

Author(s):

N.V. Belov ◽

U.I. Papiashwili ◽

B.E. Yudovich

Keyword(s):

Liquid Phase ◽

Grain Boundaries ◽

Benzoyl Peroxide ◽

Phase Contrast ◽

Active Role ◽

Point Of View ◽

Hardened Cement ◽

Hydrated Cement ◽

Hardened Cement Paste

It has been almost universally adopted that dissolution of solids proceeds with development of uniform, continuous frontiers of reaction.However this point of view is doubtful / 1 /. E.g. we have proved the active role of the block (grain) boundaries in the main phases of cement, these boundaries being the areas of hydrate phases' nucleation / 2 /. It has brought to the supposition that the dissolution frontier of cement particles in water is discrete. It seems also probable that the dissolution proceeds through the channels, which serve both for the liquid phase movement and for the drainage of the incongruant solution products. These channels can be appeared along the block boundaries.In order to demonsrate it, we have offered the method of phase-contrast impregnation of the hardened cement paste with the solution of methyl metacrylahe and benzoyl peroxide. The viscosity of this solution is equal to that of water.

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Potential Uses of Vinegar as a Medicine and Related in vivo Mechanisms

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000440 ◽

2016 ◽

Vol 86 (3-4) ◽

pp. 127-151 ◽

Cited By ~ 3

Author(s):

Zeshan Ali ◽

Zhenbin Wang ◽

Rai Muhammad Amir ◽

Shoaib Younas ◽

Asif Wali ◽

...

Keyword(s):

Chemical Structure ◽

Review Paper ◽

Heart Diseases ◽

Folk Medicine ◽

Active Role ◽

Current Review ◽

Different Types ◽

Positive Effect

While the use of vinegar to fi ght against infections and other crucial conditions dates back to Hippocrates, recent research has found that vinegar consumption has a positive effect on biomarkers for diabetes, cancer, and heart diseases. Different types of vinegar have been used in the world during different time periods. Vinegar is produced by a fermentation process. Foods with a high content of carbohydrates are a good source of vinegar. Review of the results of different studies performed on vinegar components reveals that the daily use of these components has a healthy impact on the physiological and chemical structure of the human body. During the era of Hippocrates, people used vinegar as a medicine to treat wounds, which means that vinegar is one of the ancient foods used as folk medicine. The purpose of the current review paper is to provide a detailed summary of the outcome of previous studies emphasizing the role of vinegar in treatment of different diseases both in acute and chronic conditions, its in vivo mechanism and the active role of different bacteria.

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Russia’s Market of Mergers and Acquisitions: Stages, Features and Prospects

Voprosy Ekonomiki ◽

10.32609/0042-8736-2009-10-23-45 ◽

2009 ◽

pp. 23-45 ◽

Cited By ~ 2

Author(s):

A. Radygin

Keyword(s):

Open Access ◽

Mergers And Acquisitions ◽

Corporate Control ◽

Active Role ◽

Data Bases ◽

2008 Financial Crisis ◽

Legal Norms ◽

Role Of The State ◽

Access Data

The article deals with key tendencies in the development of Russia’s market of mergers and acquisitions in the first decade of the 21st century. Quantitative parameters are analyzed by using available in the open access data bases for the years 2003-2008 taking into consideration new tendencies relating to 2008 financial crisis. An active role of the state played in the market of corporate control represents an important factor. Special attention is given to issues of development of Russia’s system of legal norms regulating the market of mergers and acquisitions.

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