Effects of lanosterol on in vitro maturation of porcine oocytes

[EN] FF-MAS and T-MAS sterols, intermediaries in the cholesterol biosynthetic pathway present in all cells, may represent the physiological signal that instructs the crocyte to reinitiate meiosis. The purpose of this study was to examine the hypothesis that exogenous lanosterol could be included in the sterol biosynthetic pathway from acetate to cholesterol and induce resumption of meiosis in oocytes cultured in vitro. Porcine oocytes were in vitro matured in medium supplemented with different concentrations of lanosterol. First, after 22 h of in vitro maturation, cumulus cells were recovery and Delta 7-Reductase gene expression was quantified using real-time PCR. Second, after 44 h of in vitro maturation, chromatin configuration was evaluated using Hoechst 33342. Lipid content was also evaluated at 22 and 44 In of in vitro maturation using Nile red staining. The results showed that the addition of lanosterol increased the Delta 7-Reductase gene expression and influenced resumption of meiosis using 50 and 100 mu M, as well as enhancing higher cytoplasmic lipid accumulation after in vitro maturation. The results demonstrate that exogenous lanosterol acts in the sterol biosynthetic pathway from acetate to cholesterol and it was responsible for a higher resumption of meiosis in porcine oocytes cultured in vitro. (C) 2009 Elsevier B.V. All rights reserved.Supported by the Universidad Politecnica de Valencia (Project 20081166).Marco Jiménez, F.; Llobat, L.; Vicente Antón, JS. (2010). Effects of lanosterol on in vitro maturation of porcine oocytes. Animal Reproduction Science. 117(3-4):288-294. https://doi.org/10.1016/j.anireprosci.2009.04.008S2882941173-

NPHP4 is necessary for normal photoreceptor ribbon synapse maintenance and outer segment formation, and for sperm development

Nephronophthisis (NPHP) is an autosomal recessive kidney disease that is often associated with vision and/or brain defects. To date, 11 genes are known to cause NPHP. The gene products, while structurally unrelated, all localize to cilia or centrosomes. Although mouse models of NPHP are available for 9 of the 11 genes, none has been described for nephronophthisis 4 (Nphp4). Here we report a novel, chemically induced mutant, nmf192, that bears a nonsense mutation in exon 4 of Nphp4. Homozygous mutant Nphp4nmf192/nmf192 mice do not exhibit renal defects, phenotypes observed in human patients bearing mutations in NPHP4, but they do develop severe photoreceptor degeneration and extinguished rod and cone ERG responses by 9 weeks of age. Photoreceptor outer segments (OS) fail to develop properly, and some OS markers mislocalize to the inner segments and outer nuclear layer in the Nphp4nmf192/nmf192 mutant retina. Despite NPHP4 localization to the transition zone in the connecting cilia (CC), the CC appear to be normal in structure and ciliary transport function is partially retained. Likewise, synaptic ribbons develop normally but then rapidly degenerate by P14. Finally, Nphp4nmf192/nmf192 male mutants are sterile and show reduced sperm motility and epididymal sperm counts. Although Nphp4nmf192/nmf192 mice fail to recapitulate the kidney phenotype of NPHP, they will provide a valuable tool to further elucidate how NPHP4 functions in the retina and male reproductive organs