Background:The mechanisms by which NF-B signaling is up-regulated in dystrophic muscles are unclear. Results: [Ca 2ϩ ] rest is elevated in mdx myotubes as a result of both sarcolemmal Ca 2ϩ entry and SR release, resulting in NF-B-induced iNOS expression. Conclusion: Ca 2ϩ alterations at rest modulate NF-B transcriptional activity and pro-inflammatory gene expression. Significance: This allows for understanding the mechanism that relates elevated resting calcium and altered gene expression in muscular dystrophy.
Summary Human embryos generated in vitro have a high incidence of chromosomal abnormalities that negatively affect pregnancy rate. Embryos generated in vitro secrete extracellular vesicles (EVs) into the culture medium that could be used potentially as indicators of embryo competence. This research aimed to evaluate the concentration and size of EVs and their gDNA content as an indicator of developmental competence in human embryos. Human embryos generated by intracytoplasmic sperm injection (ICSI) were classified morphologically as of either TOP, FAIR or POOR quality. Culture medium and developmentally arrested embryos (which were not able to be used for embryo transfer) were collected. Microvesicles, exosomes (MV/Exo) and apoptotic bodies (ABs) were isolated from culture medium. Nanoparticle tracking analysis (NTA) and array comparative genomic hybridization (aCGH) analysis were performed to evaluate EVs and their gDNA content. From NTA, the diameter (mean) of MVs/Exo from TOP quality embryos was higher (112.17 nm) compared with that of FAIR (108.02) and POOR quality embryos (102.78 nm) (P < 0.05). aCGH analysis indicated that MVs/Exo and ABs carried gDNA with the presence of 23 chromosome pairs. However, when arrested embryos were compared with their respective MVs/Exo and ABs, the latter had an increased rate of chromosomal abnormalities (24.9%) compared with embryos (8.7%) (P < 0.05). In conclusion, the size of EVs from culture medium might be an alternative for evaluating competence of human embryos, however more studies are needed to validate the use of gDNA from EVs as an indicator of embryo competence.
A B S T R A C T The main objective of this study was to determine whether the principal abnormality of thyroid function observed in patients with chronic renal failure, low serum triiodothyronine (T3) concentration, causes hypothyroidism at the tissue level. A partially nephrectomized (Nx) uremic rat model was developed and the following parameters of thyroid function were assessed: serum total thyroxine (TT4), total T3 (TT3), and thyrotropin and liver T3 content, and activity oftwo thyroid hormone-dependent enzymes, mitochondrial a-glycerophosphate dehydrogenase (aGPD) and cytosol malate dehydrogenase (MDH). The results were compared to those of intact control (C), thyroidectomized (Tx), and nephrectomized-thyroidectomized (NxTx) littermates.Results expressed as mean+SEM showed that Nx rats had a fivefold increase in blood urea nitrogen, (112±20 mg/dl in Nx, and 22±1 mg/dl in C) and manifested all the changes of of thyroid function observed in uremic men, including a low serum TT3 level (30±7 ng/dl in Nx and 50±6 ng/dl in C). In the liver, T3 was significantly reduced (18±2 ng/total liver in Nx and 35±3 ng/total liver in C) as well as the activities of aGPD (8.8± 1.0 and 16.1± 1.5 AOD/min per total liver in Nx and C, respectively) and MDH (6.3±1.6 and 12.6±2.2 U/total liver in Nx and C, respectively). The reduction in liver enzyme activities correlated significantly with the decrease in T3 content.The changes in Tx rats were as expected, showing a profound reduction in serum hormone levels, liver T3 content, and liver enzyme activities. Serum thyrotropin was markedly elevated to 2,390±212 ng/ml as compared to 703±61 in C and 441±87 ng/ml in Nx rats. 946The NxTx rats showed the combined effects ofnephrectomy and thyroidectomy; blood urea nitrogen was elevated to 203, and serum levels of TT4, TT3, and thyrotropin were 0.4, < 10, and 2,525, respectively. Total liver T3 and aGPD and MDH were strikingly low; the corresponding values were 3.5, 2.4, and 2.5.L-triiodothyronine replacement (0.4 ,ug/100 g body wt/d) for 4 wk in the Nx rats resulted in significant increases in liver enzyme activities, aGPD and MDH rose by 70 and 60% over their respective basal values without alteration in the severity of azotemia.From these data, we conclude that the reduction of liver T3 content in the uremic rats, accompanied by a decrease in aGPD and MDH activity, indicates the presence ofhypothyroidism at the tissue level. Restoration of enzyme activities toward normal levels after T3 administration provided further supporting evidence that the diminution in liver enzyme activity was causally related to tissue T3 deficiency.
Despite the increase in RRT services, the prevalence is lower than the Latin American average (660 pmp). Three quarters of HD and PD patients are under-dialysed. Obsolete RRT techniques are still used. The presence of Mesoamerican nephropathy influences the demographic characteristics (many young patients, two-thirds male, high prevalence in lowlands and coastlands).
Noninvasive methods are the clue to increase the efficiency of invitro-derived embryo selection without decreasing their competence. Embryos selection based on their morphology is the most used method but only 40% of selected embryos are able to implant and develop correctly. In humans, pre-implantation genetic diagnosis increases the efficiency of selection by excluding embryos with chromosomal abnormalities. However, pre-implantation genetic diagnosis needs embryonic cells, which might compromise embryo viability. On the other hand, embryos release extracellular vesicles (EVs: microvesicles and exosomes) to the culture medium that contain biological cargo-like proteins and mRNA lipids, and might contain genomic DNA (gDNA). For this study we evaluated the culture medium from embryos generated by intracytoplasmic sperm injection in a certified fertility clinic. Embryos were cultured in Global Total serum-free medium. The embryos were assessed at Day 3 of development and classified in three categories: top, fair, and poor quality. Corresponding medium was collected for isolation of EVs. The nature of EVs was confirmed by their size and concentration using nanoparticle tracking analysis (NTA), presence of surface markers (CD9, CD63, CD81, and CD40L), and morphology using transmission electron microscopy. A correlation analysis between NTA results (EV size and concentration) and embryo quality was performed. To evaluate chromosomal abnormalities of gDNA present in isolated EVs from embryo culture medium, microarray-based comparative genomic hybridization (aCGH) assay was performed. In a second experiment, aCGH analysis was performed and compared between arrested embryos and EVs isolated from corresponding culture medium. Isolated nanoparticles from embryo culture medium were positive to all markers CD9 (30.9%), CD63 (27.2%), CD81 (31.7%), CD40L (8.7%) and had a morphology accordingly to exosomes. The analysis of NTA data indicated that top-quality embryos had EVs with higher diameter (mean: 112.17nm, mode: 91.74nm) than embryos classified as fair (mean: 108.02nm, mode: 89.67nm) and poor quality (mean: 102.78nm, mode: 88.17 nm; P<0.05). The aCGH analysis showed the representation of the 23 pairs of chromosomes in EVs from culture medium and the chromosomal abnormalities were detected in chromosome 4 (C4: 6/15 (40%)) and chromosome 13 (C13: 6/15 (40%)). In the second experiment, the aCGH assay also showed abnormalities in different chromosomes from samples of EVs from culture medium (24.9%) and were more frequent than those observed in the arrested embryos (8.7%; P=0.03). However, the rate of similitude in chromosomal abnormalities between EVs and their respective embryo was 70-80%. In conclusion, the size and gDNA of EVs from culture medium might be an alternative to evaluate the competence of human embryos. This research was supported by FONDECYT-1170310 and Corfo 17Cote-72437, Chile.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.