Spermatogenesis

Why sex chromosomes turn over and remain undifferentiated in some taxa, whereas they degenerate in others, is still an area of ongoing research. The recurrent occurrence of homologous and homomorphic sex chromosomes in distantly related taxa suggests their independent evolution or continued recombination since their first emergence. Fishes display a great diversity of sex-determining systems. Here, we focus on sex chromosome evolution in haplochromines, the most species-rich lineage of cichlid fishes. We investigate sex-specific signatures in the Pseudocrenilabrus philander species complex, which belongs to a haplochromine genus found in many river systems and ichthyogeographic regions in northern, eastern, central, and southern Africa. Using whole-genome sequencing and population genetic, phylogenetic, and read-coverage analyses, we show that one population of P. philander has an XX–XY sex-determining system on LG7 with a large region of suppressed recombination. However, in a second bottlenecked population, we did not find any sign of a sex chromosome. Interestingly, LG7 also carries an XX–XY system in the phylogenetically more derived Lake Malawi haplochromine cichlids. Although the genomic regions determining sex are the same in Lake Malawi cichlids and P. philander , we did not find evidence for shared ancestry, suggesting that LG7 evolved as sex chromosome at least twice in haplochromine cichlids. Hence, our work provides further evidence for the labile nature of sex determination in fishes and supports the hypothesis that the same genomic regions can repeatedly and rapidly be recruited as sex chromosomes in more distantly related lineages.

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“…Among the other genes, we detected two genes involved in spermatogenesis, psmb2 (Gupta 2005) and kelch10 (Yan et al. 2004).…”

Section: Resultsmentioning

confidence: 99%

Repeated Evolution Versus Common Ancestry: Sex Chromosome Evolution in the Haplochromine CichlidPseudocrenilabrus philander

Böhne

Weber

Rajkov

et al. 2019

Genome Biology and Evolution

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“…Unlike somatic LDHA and LDHB, the C subunit of LDH designated as LDHC and a product of the LDHC ( Ldh-3 in murine) gene is mostly found in spermatogenic cells of the testis. LDHC is synthesised in the testis throughout sexual maturation, and it makes up the majority of mature spermatozoa [ 118 , 123 , 124 ]. While LDHA and LDHB are found in most somatic tissues, LDHC was detected in the testes’ germinal epithelium.…”

Section: Ldha: the Target Protein For Covid-19 Therapymentioning

confidence: 99%

The Lactate and the Lactate Dehydrogenase in Inflammatory Diseases and Major Risk Factors in COVID-19 Patients

Gupta

2022

Inflammation

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— Lactate dehydrogenase (LDH) is a terminating enzyme in the metabolic pathway of anaerobic glycolysis with end product of lactate from glucose. The lactate formation is crucial in the metabolism of glucose when oxygen is in inadequate supply. Lactate can also be formed and utilised by different cell types under fully aerobic conditions. Blood LDH is the marker enzyme, which predicts mortality in many conditions such as ARDS, serious COVID-19 and cancer patients. Lactate plays a critical role in normal physiology of humans including an energy source, a signaling molecule and a pH regulator. Depending on the pH, lactate exists as the protonated acidic form (lactic acid) at low pH or as sodium salt (sodium lactate) at basic pH. Lactate can affect the immune system and act as a signaling molecule, which can provide a “danger” signal for life. Several reports provide evidence that the serum lactate represents a chemical marker of severity of disease similar to LDH under inflammatory conditions. Since the mortality rate is much higher among COVID-19 patients, associated with high serum LDH, this article is aimed to review the LDH as a therapeutic target and lactate as potential marker for monitoring treatment response of inflammatory diseases. Finally, the review summarises various LDH inhibitors, which offer potential applications as therapeutic agents for inflammatory diseases, associated with high blood LDH. Both blood LDH and blood lactate are suggested as risk factors for the mortality of patients in serious inflammatory diseases.

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“…A possible explanation for the increase in sperm concentration could be given by the increased blood and seminal plasma levels of IGF-I. It is known, in fact, that this hormone, together with IGF-II and insulin has several effects on Sertoli cells, increasing proliferation, affecting steroidogenesis, and promoting spermatogonia differentiation into primary spermatocytes [ 11 , 46 ]. However, the effect of dietary CLA supplementation on the volume of the ejaculates is still unclear and needs further investigation.…”

Section: Resultsmentioning

confidence: 99%

“…The lack of significance could possibly be explained by the high variability between samples justified by the high standard error. Although ROS are known for their damaging effects on spermatozoa, low levels and controlled concentration are essential for participation in signal transduction of sperm capacitation and acrosome reaction [ 11 ]. The decrease in ROS could be probably due to increase in protective action of GSH, as result of the CLA supplementation, as supported by other studies [ 58 , 59 ].…”

Section: Resultsmentioning

confidence: 99%

“…In particular, insulin-like growth factor-I (IGF-I) seems to play a significant role in differentiation, proliferation and steroidogenesis, and its derangement may be involved in male infertility [ 7 , 9 , 10 ]. In fact, IGF-I and insulin-like growth factor II (IGF-II), which are produced in the liver, have been identified in the testicles [ 11 ]; they are secreted by Leydig and Sertoli cells [ 11 , 12 ], and receptors for IGF-I have been reported in the spermatogonia, spermatocytes, spermatids, and spermatozoa [ 13 , 14 ]. Furthermore, studies indicate the possible role of IGF-I on sperm viability and motility in mouse [ 15 ], cattle [ 14 ], and buffalo [ 16 , 17 ].…”

Section: Introductionmentioning

confidence: 99%

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Effects of Dietary Supplementation of Conjugated Linoleic Acids and Their Inclusion in Semen Extenders on Bovine Sperm Quality

Liman

Franco

Cardoso

et al. 2021

Animals

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Isomers of conjugated linoleic acid (CLA) enhances circulating insulin-like growth factor I (IGF-I) levels. Furthermore, fertility rate of breeding bulls is positively correlated to seminal plasma IGF-I concentration. Our objective was to evaluate the effect of dietary CLA supplementation and inclusion to the semen extender on bovine semen quality and freezability. Fourteen bulls, randomly assigned to control (CTL) and CLA (50 g/day) groups, were supplemented for 10 weeks. Samples were collected at Weeks −2 (before supplementation), 0, 4, 6 (during supplementation), 10, and 11 (after supplementation). Blood and seminal plasma were analyzed for IGF-I; the ejaculates were frozen in the following subgroups: CTL (no addition to semen extender), CLA c9, t11 (50 µM), CLA c9, t11 (100 µM), CLA t10, c12 (50 µM), CLA t10, c12 (100 µM), and CLA mix (50 µM each of CLA c9, t11 and CLA t10, c12). Sperm motility, morphology, viability, mitochondrial membrane potential, and reactive oxidative species were assessed. CLA supplementation decreased ejaculates’ total volume, increased sperm concentration, beat cross frequency, and decreased oxidative stress; it also increased plasma and seminal plasma IGF-I levels compared to the CTL. The inclusion of CLA c9, t11 100 µM and CLA mixture in the extender increased live spermatozoa percentage post-thawing compared to other groups. Our results show a beneficial effect of CLA supplementation on semen quality; however, further studies evaluating fertilization rates are necessary to corroborate the results.

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Spermatogenesis

Cited by 3 publications

References 70 publications

Repeated Evolution Versus Common Ancestry: Sex Chromosome Evolution in the Haplochromine CichlidPseudocrenilabrus philander

Repeated Evolution Versus Common Ancestry: Sex Chromosome Evolution in the Haplochromine CichlidPseudocrenilabrus philander

The Lactate and the Lactate Dehydrogenase in Inflammatory Diseases and Major Risk Factors in COVID-19 Patients

Effects of Dietary Supplementation of Conjugated Linoleic Acids and Their Inclusion in Semen Extenders on Bovine Sperm Quality

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