The glycoprotein hormones, ACTH, TSH, FSH, and LH regulate diverse functions in endocrine cells. Although cAMP and PKA have long been shown to mediate specific intracellular signaling events including the transcription of specific genes via the CREB-CBP complex, recent observations have indicated that PKA does not account for all of the intracellular targets of cAMP. For example, TSH stimulation of thyroid cell proliferation is not completely blocked by PKA inhibitors. TSH and FSH can stimulate PKB phosphorylation by a PKAindependent but PI3-K/PDK1-dependent pathway. An FSH inducible kinase, Sgk, has recently been shown to be a close relative of PKB. Sgk is also a target of PI3-K-PDK1 pathway, indicating that some effects previously ascribed to PKB may be mediated by this inducible kinase. The identification of novel cAMP-binding proteins that exhibit guanine nucleotide exchange (GEF) activity (cAMP-GEFS; Epacs) has open new doors for cAMP action that include activation of small GTPases such as Rap1a, Rap2, and possibly Ras. These GTPases are known activators of downstream kinase cascades, including p38MAPK and Erk1/2 as well as PI3-K. Thus, FSH and TSH activation of PKB and Sgk may occur via this alternative cAMP pathway that involves cAMP-GEFs and the activation of the PI3-K/PDK1 pathway.

/pdf/new-signaling-pathways-for-hormones-and-cyclic-adenosine-3-5-g5t76cp49p.pdf

New signaling pathways for hormones and cyclic adenosine 3',5'-monophosphate action in endocrine cells.

Three major phases compose spermatogenesis: mitotic proliferation of spermatogonia, meiosis of spermatocytes, and spermiogenesis, the restructuring of spermatids into flagellated spermatozoa. The process is fuelled by stem cells that, when dividing, either self-renew or produce spermatogonia that are committed to proliferation, meiosis, and spermiogenesis. During all phases, germ cells are in close contact with and require the structural and functional support of Sertoli cells. In contrast to germ cells, these somatic cells express receptors for sex steroids and follicle-stimulating hormone (FSH), the most important hormones that regulate spermatogenesis. A typical Sertoli cell response to an endocrine stimulus would be to change the release of a growth factor that would then mediate the hormone's effect to the germ cells. Recent studies in the Japanese eel have shown, for example, that in the absence of gonadotropin Sertoli cells produce a growth factor (an orthologue of anti-Mullerian hormone) that restricts stem cell divisions to the self-renewal pathway; also estrogens stimulate stem cell renewal divisions but not spermatogonial proliferation. Gonadotropin or 11-ketotestosterone (11-KT) stimulation, however, induces spermatogonial proliferation, which is in part mimicked by another Sertoli cell-derived growth factor (activin B). Since FSH (besides luteinizing hormone, LH) stimulates steroidogenesis in fish, and since FSH is the only gonadotropin detected in the plasma of sexually immature salmonids, increased FSH signalling may be sufficient to initiate spermatogenesis by activating both Sertoli cell functions and 11-KT production. Another important androgen is testosterone (T), which seems to act via feedback mechanisms that can compromise FSH-dependent signalling or steroidogenesis. The testicular production of T and 11-KT therefore needs to be balanced adequately. Further research is required to elucidate in what way(s) 11-KT stimulates later stages of development, such as entry into meiosis and spermiogenesis. At this period, LH becomes increasingly important for the regulation of androgen production. Results from mammalian models suggest that during the later phases, the control of germ cell apoptosis via Sertoli cell factors is an important regulatory mechanism. In many species, sperm cells cannot fertilize eggs until having passed a maturation process known as capacitation, which includes the acquisition of motility. Progestins that are produced under the influence of LH appear to play an important role in this context, which involves the control of the composition of the seminal plasma (e.g., pH values).

Spermatogenesis and its endocrine regulation

Evaluation of testicular functions (production of sperm and androgens) is an important aspect of preclinical safety assessment and testicular toxicity is comparatively far more common than ovarian toxicity This chapter focuses (1) on the histological sequelae of disturbed reproductive endocrinology in rat, dog and nonhuman primates and (2) provides a review of our current understanding of the roles of gonadotropins and androgens The response of the rodent testis to endocrine disturbances is clearly different from that of dog and primates with different germ cell types and spermatogenic stages being affected initially and also that the end-stage spermatogenic involution is more pronounced in dog and primates compared to rodents Luteinizing hormone (LH)/testosterone and follicle-stimulating hormone (FSH) are the pivotal endocrine factors controlling testicular functions The relative importance of either hormone is somewhat different between rodents and primates Generally, however, both LH/testosterone and FSH are necessary for quantitatively normal spermatogenesis, at least in non-seasonal species

https://www.tandfonline.com/doi/pdf/10.1080/21565562.2014.996025

Endocrine control of spermatogenesis: Role of FSH and LH/ testosterone.

In the past century, tremendous progress has been made in our understanding of the endocrine regulation of fertility. The identification and purification of peptide and steroid hormones and our knowledge of their actions in endocrine cells has led to major advances in contraceptive development, in vitro fertilization, and endocrine therapy. The advances in molecular biology have led to our understanding of how hormones and growth factors regulate the expression of specific genes in endocrine cells. Today, the disruption and deletion of selected genes in mice is becoming routine and null mutations for many proteins expressed in and regulating endocrine cell function have been generated. These mutant mice have brought molecular reproductive endocrinologists full circle. We have returned to ablation-replacement bioassays used by the early endocrinologists, albeit in a much more sophisticated way and with more elaborate and specific mechanisms. The new age endocrinology and our knowledge of endocrine cell function will expand even more explosively now that the cloning of the mouse and human genomes nears completion. In the next century, new hormones, new receptors, new signaling pathways for old receptors, and new transcription factors will no doubt be identified and our understanding of the complex pathways regulating endocrine cells should be markedly enhanced. The goal of this minireview is to highlight some recent advances in our knowledge of how hormones and growth factors impact the formation and growth as well as the termination of the ovarian follicle. Of particular relevance is the importance of the microenvironments that control oocytecumulus cell functions and granulosa-theca cell functions within the follicle and how hormones, such as FSH and LH, impact these microenvironments. Highlighting what we know about the ovarian follicle in 2001 may help us set goals for 2100. Hopefully, basic science and clinical discoveries in the next century will unravel the endocrine, molecular, and cellular bases of premature ovarian failure, polycystic ovarian syndrome, and ovarian cancer.

/pdf/perspective-the-ovarian-follicle-a-perspective-in-2001-245s9qggh2.pdf

Perspective: the ovarian follicle--a perspective in 2001.

Hormonal control of germ cell development and spermatogenesis.

Activation of Extracellular-regulated Kinase Pathways in Ovarian Granulosa Cells by the Novel Growth Factor Type 1 Follicle-stimulating Hormone Receptor: ROLE IN HORMONE SIGNALING AND CELL PROLIFERATION

In the highly organized and complex process of mammalian spermatogenesis, the development of an undifferentiated diploid germ cell into a fully differentiated and mature spermatozoon is orchestrated in a time frame unique for each species including man. If the various hormonal signals including environmental cues that play a critical part in initiating these events are not properly executed, various deficiencies including delay in sexual maturity or puberty are likely. In this study we have followed testicular development and spermatogenesis in the FSH receptor knockout (FORKO) mice from Day 7 onward by using histology and quantitative DNA flow cytometry. The drastic reduction in testicular weight and shrinkage of seminiferous tubules that occurred at this early age persisted into the adult stage in the FORKOs, suggesting inhibition of the initial developmental processes. The round spermatids that were clearly abundant on Day 21 in the wild-type and heterozygous males were few and present only in some tubules of the FORKOs. There were no elongated spermatids in FORKO males on Day 35. The sperm produced by Day 49 FORKOs were already aberrant, a feature that persisted into adulthood in these animals. As all these changes occurred in a background of normal circulating testosterone levels, we may conclude that the delay in testicular development is a consequence of the loss of FSH-receptor signaling. The delay in sexual maturity of FORKOs was accompanied by reduction in fertility as evidenced by mating studies. Based on these data we suggest that the FORKO mouse might be a useful experimental model to define the molecular mechanisms that underlie the delay in puberty.

https://bioone.org/journals/biology-of-reproduction/volume-65/issue-2/biolreprod65.2.522/Delay-in-Sexual-Maturity-of-the-Follicle-Stimulating-Hormone-Receptor/10.1095/biolreprod65.2.522.pdf

Delay in Sexual Maturity of the Follicle-Stimulating Hormone Receptor Knockout Male Mouse

Poultry is the biggest growing sector in our country. In terms of employment and food production, the poultry sector’s contribution to nation-building is enormous. Being one of the biggest sectors, it has its issues in terms of managing poultry waste. Even though poultry waste management companies are handling it well due to the enormous generation of waste in the present day, this seems to be a herculean task. To address this issue of managing poultry waste, this research proposes the usage of ML algorithms coupled with IoT. In this work, we propose an android application that acts as an interface between poultry farms and poultry waste management companies to reduce the amount of poultry waste. The IoT-powered devices are installed in waste containers which gives real-time data about the smart bin. Information and Communication Technology (ICT) makes the poultry farm exchange information with the poultry waste management companies and provide them with high-quality services. Therefore, the objective of this research is to explore and investigate the current condition of the poultry waste recycling system and study the problems faced by poultry waste management companies in handling them and build a use case diagram to design a computerized system to deal with the challenges of recycling poultry waste.

Poda Suresh Babu

Papers

Activation of Extracellular-regulated Kinase Pathways in Ovarian Granulosa Cells by the Novel Growth Factor Type 1 Follicle-stimulating Hormone Receptor: ROLE IN HORMONE SIGNALING AND CELL PROLIFERATION

Delay in Sexual Maturity of the Follicle-Stimulating Hormone Receptor Knockout Male Mouse

An IoT and ML-based Poultry Waste Management System