Glycogen metabolism in human fetal testes

Muscle glycogen synthase isoform is responsible for testicular glycogen synthesis: glycogen overproduction induces apoptosis in male germ cells.

Abstract: Glycogen is the main source of glucose for many biological events. However, this molecule may have other functions, including those that have deleterious effects on cells. The rate-limiting enzyme in glycogen synthesis is glycogen synthase (GS). It is encoded by two genes, GYS1, expressed in muscle (muscle glycogen synthase, MGS) and other tissues, and GYS2, primarily expressed in liver (liver glycogen synthase, LGS). Expression of GS and its activity have been widely studied in many tissues. To date, it is not clear which GS isoform is responsible for glycogen synthesis and the role of glycogen in testis. Using RT-PCR, Western blot and immunofluorescence, we have detected expression of MGS but not LGS in mice testis during development. We have also evaluated GS activity and glycogen storage at different days after birth and we show that both GS activity and levels of glycogen are higher during the first days of development. Using RT-PCR, we have also shown that malin and laforin are expressed in testis, key enzymes for regulation of GS activity. These proteins form an active complex that regulates MGS by poly-ubiquitination in both Sertoli cell and male germ cell lines. In addition, PTG overexpression in male germ cell line triggered apoptosis by caspase3 activation, proposing a proapoptotic role of glycogen in testis. These findings suggest that GS activity and glycogen synthesis in testis could be regulated and a disruption of this process may be responsible for the apoptosis and degeneration of seminiferous tubules and possible cause of infertility.

Effect of Thaumatococcus daniellii leaf rat-feed on potassium bromate induced testicular toxicity

Abstract: Objective To evaluated the antioxidant and protective effect of Thaumatococcus daniellii (T. daniellii) on rat feed on potassium bromate (KBrO3) toxicity in male rat testes. Methods Thirty male albino rats of average weight 140 ± 5 g were randomly grouped into 5 with six rats per group. The rats in group A (positive control) and test groups (C, D and E) were orally given 0.5 mL of 10 mg/kg body weight of KBrO3 daily. The animals in the negative control (group B) and positive control were fed with commercial rat feed while the animals in the tests groups were fed with 10%, 20% and 30% T. daniellii leaf rat feed respectively. The treatment was carried out for 14 days consecutively, and the animals were sacrificed 24 h after the last day of the treatment. Results Biochemical assays were carried out on the testicular homogenates. The results showed significant increase (P < 0.05) in malondialdhyde, total protein, and superoxide dismutase as well as testicular glycogen in the positive control compared to test groups. The histopathological result showed testicular cellular degeneration in the positive control compared to the test animals which showed normal cell due to protective effect of the leaf. Conclusions The biochemical and histopathological results in this present study showed testicular toxicity in the rats administered with KBrO3 and T. daniellii leaf protective effect on the testicular function toxicity in rats fed with T. daniellii leaf rat feed.

Assessment of Molybdenum Induced Alteration in Oxidative Indices, Biochemical Parameters and Sperm Quality in Testis of Wistar Male Rats

Abstract: The present study was carried out to investigate the effects of ammonium molybdate on lipid peroxidation, antioxidant, biochemical and semen parameters in male Wistar rats. Group I served as control while group II, III and IV received 50, 100 and 150 mg kgG b.wt. dayG ammonium molybdate orally respectively for 60 days. Group V rats received 150 mg kgG b.wt. dayG for 60 days and thereafter left for recovery study for 60 days. The present study examined the effects of ammonium molybdate on serum testosterone, Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) along with sperm parameters. Estimations were also made for marker biochemical and antioxidant parameters in testis. Ammonium molybdate treatment resulted in a dose dependent reduction in serum testosterone, FSH, LH, sperm count, motility and viability. The concentration of total protein and sialic acid as well as activities of acid phosphatase (ACP) and alkaline phosphatase (ALP) were decreased in a dose dependent manner while there was a significant increase in the glycogen and cholesterol level in testis. The level of Thiobarbituric Acid Reactive substance (TBARs) was increased while the activities of superoxide dismutase and concentration of glutathione and ascorboic acid was decreased significantly in testis of rats treated with ammonium molybdate. All the parameters showed significant improvement after 60 days of treatment withdrawal in highest dose group. The findings suggested that ammonium molybdate exerts a deleterious effect on testicular function by altering biochemical and antioxidant status of the testes.

The Many Faces of Carbohydrate Metabolism in Male Germ Cells: From Single Molecules to Active Polymers

Abstract: Spermatogenesis is a complex physiological process that involves cell proliferation, meiotic division and a final cell differentiation of post-meiotic cells into spermatozoa. During this process male germ cells also undergo a metabolic differentiation process, in which post-meiotic spermatogenic cells (spermatids) but not meiotic spermatogenic cells (spermatocytes) respond differentially to D-glucose metabolism, glucose transporters (GLUTs) distribution and utilization of non-hexose substrates, such as lactate/pyruvate or dihydroxyacetone. These differences might be explained by the requirement for a specific metabolic process to support cell differentiation or in some cases, cell viability. In addition, though glycogen is considered to be the main glucose store, in male germ cells this polymer may play a novel role in cell proliferation, acting as a new marker for apoptotic events in testicular tissue via a yet unknown mechanism. In this article, we summarize the main metabolic changes that occur during male germ differentiation, with a specific focus on metabolic sources during spermatocyte to spermatid transition. The latter considering that these cells come from the same cell linage as specialized cells, but are not isolated from their environment, describing the roles from single molecules to polymers on the viability of male germ cells.

Circular RNA profile in liver tissue of EpCAM knockout mice

Abstract: Epithelial cell adhesion molecule (EpCAM) is highly expressed during liver development and carcinogenesis, However, its functions and underlying mechanisms remain unclear. Clustered regularly interspaced short palindromic repeats (CRISPRs)/CRISPR‑associated protein 9 (Cas9) technology was used in the current study to establish EpCAM‑/‑ mice. The expression of EpCAM in the livers of the mice at embryonic day (E)18.5 and post‑natal day (P)0 was detected by immunofluorescence staining. The expression of genes associated with the development and glycogen metabolism was also assessed by reverse transcription‑quantitative PCR. Additionally, the liver tissue of the EpCAM‑/‑ and wild‑type mice was used for non‑coding RNA sequencing. The results of RNA sequencing revealed 11 up‑regulated and 12 downregulated circular RNAs (circRNAs). Kyoto Encyclopedia of Genes and Genomes analysis for resource genes determined that the top altered pathways included cell junctions, cell cycle, immune signaling and metabolism. This analysis was also utilized to predict the target association of the circRNA‑microRNA‑mRNA network. The comprehensive liver tissue circRNA expression profiles produced in the present study may help to elucidate the functions and mechanisms of EpCAM during liver development.

Protein Measurement with the Folin Phenol Reagent

Abstract: Since 1922 when Wu proposed the use of the Folin phenol reagent for the measurement of proteins, a number of modified analytical procedures utilizing this reagent have been reported for the determination of proteins in serum, in antigen-antibody precipitates, and in insulin. Although the reagent would seem to be recommended by its great sensitivity and the simplicity of procedure possible with its use, it has not found great favor for general biochemical purposes. In the belief that this reagent, nevertheless, has considerable merit for certain application, but that its peculiarities and limitations need to be understood for its fullest exploitation, it has been studied with regard to effects of variations in pH, time of reaction, and concentration of reactants, permissible levels of reagents commonly used in handling proteins, and interfering substances. Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.

Histochemistry, theoretical and applied

Abstract: A. G. E. Pearse is a relative newcomer to the field of histochemistry. He holds an M.D. degree from the University of Cambridge and is now Lecturer in Histochemistry at the Postgraduate Medical School, University of London. One of his first contributions to histochemistry consisted of a critical review of its methodology and interpretation, written for pathologists and appearing in the British Journal of Clinical Pathology 4: 1 (1951). He has also introduced a number of new or modified techniques. Perhaps those having the greatest interest for endocrinologists are presented in a series of papers concerning the demonstration of the glycoprotein hormones of the anterior pituitary gland (Nature 162: 651, 1948; J. Path. & Bad. 61: 195, 1949, 64: 791 & 811, 1952; Stain Technol. 25: 95, 1950). The present volume comprises 17 chapters, beginning with a brief but fairly inclusive history of the development of this branch of science and continuing with 2 chapters on methods of fixation and sectioning, 3 on the staining of proteins, 4 on the demonstration of enzymes, 1 on the use of enzymes as histochemical reagents, and 1 each on carbohydrates, lipids, aldehydes and ketones, pigments, inorganic substances, and physical methods. The book concludes with appendices which give the detailed steps of the histochemical techniques which Dr. Pearse has himself found most useful for demonstrating various tissue constituents. Complete author and subject indices follow. A further valuable feature of the book consists of numerous black-and-white and a few colored photomicrographs illustrating the appearance of sections prepared by some of the histochemical methods discussed. A rash of books devoted entirely or largely to histochemical techniques has appeared in the last few years. Outstanding are the treatises by Lillie (1948), Romeis (1948, 15th ed., German), Glick (1949), Gatenby and Beams (1950, 11th ed.), Gomori (1952), and Lison (1953, 2nd ed., French). In this reviewer's opinion, the new Pearse bids fair to become the leader, even amongst so notable a collection. In each chapter, Dr. Pearse reviews the chemistry and biological importance of the substances in question and then goes on to discuss critically the methods used for their demonstration and differentiation. The bibliographic references are numerous and appear to include most of the major contributions in each area. Pearse has omitted some references which appear fundamental, for example, the definitive experimental paper and review by Marcus Singer concerning the nature of acidic and basic staining of proteins (/. Biol. Chem. 75: 133, 1948; Internal. Rev. Cytol. I: 211, 1952). Likewise, the techniques which he has selected to give in detail represent his particular preferences, whereas numerous methods which are possibly equally satisfactory are barely mentioned. While Pearse's omissions in this respect are not serious, the usefulness of some methods which he has overlooked should not be lost sight of. Needless to say, in a field which is growing so rapidly and to which several journals are now entirely devoted, no book can long remain up-to-date.

Oxford reviews of reproductive biology

Abstract: Sex determination in mammals, A McLares metabolism of the pre-implantation mammalian embryo, Ho Leese the physiology of penile erection, KE Creed et al the biology of the placental prolactin growth hormone gene family, Isabel A Forsyth the development of the normal human breast, D Laurence et al hormones and breast cancer, RD Bulbrook the control of corpus luteum function in domestic ruminants, Hector W Alila and Joseph P Dowd nutrition and reproduction, H l'Anson et al

Oxford Reviews of Reproductive Biology

Abstract: Sex determination in mammals, A. McLares metabolism of the pre-implantation mammalian embryo, Ho Leese the physiology of penile erection, K.E. Creed et al the biology of the placental prolactin growth hormone gene family, Isabel A. Forsyth the development of the normal human breast, D. Laurence et al hormones and breast cancer, R.D. Bulbrook the control of corpus luteum function in domestic ruminants, Hector W. Alila and Joseph P. Dowd nutrition and reproduction, H. l'Anson et al.