Aim： To investigate if interleukin-6 （IL-6）, interleukin-8 （IL-8）, interleukin- 10 （IL-10）, interferon-gamma （IFN-γ） or tumor necrosis factor-alpha （TNF-α） are able to stimulate the level of lipid peroxid...Aim： To investigate if interleukin-6 （IL-6）, interleukin-8 （IL-8）, interleukin- 10 （IL-10）, interferon-gamma （IFN-γ） or tumor necrosis factor-alpha （TNF-α） are able to stimulate the level of lipid peroxidation of sperm membranes, either alone or in the presence of leukocytes. Methods： Semen samples from normozoospermic donors were prepared by density gradient. The sperms were exposed to the indicated cytokines, at physiological and infection-inflammation concentrations, in the absence or presence of leukocytes. Lipid peroxidation of the sperm membranes was determined by measuring malondialdehyde （MDA） and 4-hydroxialkenals （HAE） formation. Results： TNF-α, IL-8 and IFN-γ increased the level of sperm membrane lipid peroxidation when tested at physiological concentrations. At infectioninflammation concentrations, only IL-8 was able to produce a higher effect. When assayed in the presence of leucocytes, IL-8 and TNF-α showed a higher effect at infection-inflammation concentrations than at physiological concentrations. Finally, IL-8 showed a higher effect in the presence of leukocytes than in their absence at both physiological and infection-inflammation concentrations. TNF-α also showed a higher effect when assayed in the presence of leuko- cytes than in their absence, but only at infection-inflammation concentrations. There was no effect of IL-6 or IL-10 in any of the tested conditions. Conclusion： Several pro-inflammatory cytokines at physiological concentrations increase the level of lipid peroxidation of sperm membranes, which could be important for the sperm fecundation process. However, infection-inflammation concentrations of some cytokines, such as IL-8 and TNF-α, either alone or in the presence of leukocytes, could drive the lipid peroxidation of the spermatozoa plasma membrane to levels that can affect the sperm fertility capacity.展开更多
Hox and ParaHox genes constitute two families of developmental regulators that pattern the Anterior-Posterior body axis in all bilaterians. The members of these two groups of genes are usually arranged in genomic clus...Hox and ParaHox genes constitute two families of developmental regulators that pattern the Anterior-Posterior body axis in all bilaterians. The members of these two groups of genes are usually arranged in genomic clusters and work in a coordinated fashion, both in space and in time. While the mechanistic aspects of their action are relatively well known, it is still unclear how these systems evolved. For instance, we still need a proper model of how the Hox and ParaHox clusters were assembled over time. This problem is due to the shortage of information on gene complements for many taxa （mainly basal metazoans） and the lack of a consensus phylogenetic model of animal relationships to which we can relate our new findings. Recently, several studies have shown that the Acoelomorpha most probably represent the first offshoot of the Bilateria. This finding has prompted us, and others, to study the Hox and ParaHox complements in these animals, as well as their activity during development. In this review, we analyze how the current knowledge of Hox and ParaHox genes in the Acoelomorpha is shaping our view of bilaterian evolution.展开更多
文摘Aim： To investigate if interleukin-6 （IL-6）, interleukin-8 （IL-8）, interleukin- 10 （IL-10）, interferon-gamma （IFN-γ） or tumor necrosis factor-alpha （TNF-α） are able to stimulate the level of lipid peroxidation of sperm membranes, either alone or in the presence of leukocytes. Methods： Semen samples from normozoospermic donors were prepared by density gradient. The sperms were exposed to the indicated cytokines, at physiological and infection-inflammation concentrations, in the absence or presence of leukocytes. Lipid peroxidation of the sperm membranes was determined by measuring malondialdehyde （MDA） and 4-hydroxialkenals （HAE） formation. Results： TNF-α, IL-8 and IFN-γ increased the level of sperm membrane lipid peroxidation when tested at physiological concentrations. At infectioninflammation concentrations, only IL-8 was able to produce a higher effect. When assayed in the presence of leucocytes, IL-8 and TNF-α showed a higher effect at infection-inflammation concentrations than at physiological concentrations. Finally, IL-8 showed a higher effect in the presence of leukocytes than in their absence at both physiological and infection-inflammation concentrations. TNF-α also showed a higher effect when assayed in the presence of leuko- cytes than in their absence, but only at infection-inflammation concentrations. There was no effect of IL-6 or IL-10 in any of the tested conditions. Conclusion： Several pro-inflammatory cytokines at physiological concentrations increase the level of lipid peroxidation of sperm membranes, which could be important for the sperm fecundation process. However, infection-inflammation concentrations of some cytokines, such as IL-8 and TNF-α, either alone or in the presence of leukocytes, could drive the lipid peroxidation of the spermatozoa plasma membrane to levels that can affect the sperm fertility capacity.
文摘Hox and ParaHox genes constitute two families of developmental regulators that pattern the Anterior-Posterior body axis in all bilaterians. The members of these two groups of genes are usually arranged in genomic clusters and work in a coordinated fashion, both in space and in time. While the mechanistic aspects of their action are relatively well known, it is still unclear how these systems evolved. For instance, we still need a proper model of how the Hox and ParaHox clusters were assembled over time. This problem is due to the shortage of information on gene complements for many taxa （mainly basal metazoans） and the lack of a consensus phylogenetic model of animal relationships to which we can relate our new findings. Recently, several studies have shown that the Acoelomorpha most probably represent the first offshoot of the Bilateria. This finding has prompted us, and others, to study the Hox and ParaHox complements in these animals, as well as their activity during development. In this review, we analyze how the current knowledge of Hox and ParaHox genes in the Acoelomorpha is shaping our view of bilaterian evolution.
