Dysregulated microRNAs in sapje and sapje-like zebrafish
ABSTRACT: MicroRNAs were isolated from wild type (SW and SLW; sapje-wild type littermates, sapje-like-wild type littermates) and sapje and sapje-like fish at 5 and 30 days post fertilization (dpf) Comparison of wildtype and sapje and sapje-like fish at 5 and 30 dpf to identify commonly dysregulated microRNA biosignature This experiment includes 2 groups per cohort (SW1, 2 vs S1, S2 at 5 and 30 dpf) and (SLW1,2 vs SL1, 2 at 5 and 30 dpf)
Project description:Background: There is a limited capacity to repair damage in the mammalian heart after birth, which is primarily due to the inability of cardiomyocytes to proliferate after birth. This is in contrast to zebrafish and salamander, in which cardiomyocytes retain the ability to proliferate throughout life and can regenerate their heart after significant damage. Recent studies in zebrafish and rodents implicate microRNAs (miRNAs) in the regulation of genes responsible for cardiac cell cycle progression and regeneration, in particular, miR-133a, the miR-15 family, miR-199a and miR-590. However, the significance of these miRNAs and miRNA in general in the regulation of cardiomyocyte proliferation in large mammals, including humans, where the timing of heart development relative to birth is very different than in rodents, is unclear. To determine the involvement of miRNAs in the down-regulation of cardiomyocyte proliferation occurring before birth in large mammals, we investigated miRNA and target gene expression in sheep hearts before and after birth. The experimental approach included targeted transcriptional profiling of miRNA and target mRNA previously identified in rodent studies as well as genome-wide miRNA profiling using microarrays. Results: The cardiac expression of miR-133a increased and its target gene IGF1R decreased with increasing age, reaching their respective maximum and minimum abundance when the majority of ovine cardiomyocytes were quiescent. The expression of the miR-15 family members was variable with age, however, four of their target genes decreased with age. These latter profiles are inconsistent with the direct involvement of this family of miRNA in cardiomyocyte quiescence in late gestation sheep. The expression patterns of ‘pro-proliferative’ miR-199a and miR-590 were also inconsistent with their involvement in cardiomyocyte quiescence. Consequently, miRNA microarray analysis was undertaken, which identified six discrete clusters of miRNA with characteristic developmental profiles. The functions of predicted target genes for the miRNA in four of the six clusters were enriched for aspects of cell division and regulation of cell proliferation suggesting a potential role of these miRNA in regulating cardiomyocyte proliferation. Conclusion: The results of this study show that the expression of miR-133a and one of its target genes is consistent with it being involved in the suppression of cardiomyocyte proliferation, which occurs across the last third of gestation in sheep. The expression patterns of the miR-15 family, miR-199a and miR-590 were inconsistent with direct involvement in the regulation cardiomyocyte proliferation in sheep, despite studies in rodents demonstrating that their manipulation can influence the degree of cardiomyocyte proliferation. miRNA microarray analysis suggests a coordinated and potentially more complex role of multiple miRNA in the regulation of cardiomyocyte quiescence and highlights significant differences between species that may reflect their substantial differences in the timing of this developmental process. RNA, (2 µg) from three heart samples from each of the 91 d (fetus), 141 d (fetus), 5 d (postnatal) and 173 d (postnatal) groups, was used for analysis according to standard procedures. The experimental design included three biological replicates from each of the four normal developmental ages in sheep and thus a total of 12 samples was analyzed.
Project description:We determined pattern of miRNAs of mild-to-severe human pulmonary arterial hypertension and compared the with health controls using microarray and subsequently validated by QPCRs Manuscript Title: Circulating miRNAs as novel marker for pulmonary hypertension. (Under Revision Plos One Manuscript ID: PONE-D-12-38535) Performed microRNA microarray from one healthy and one severe PH patient and compared the results using additional samples by qPCR for other miRNAs
Project description:BACKGROUND - MicroRNAs (miRs) are a class of small non-coding RNAs that regulate gene expression. Transgenic models have proved that a single miR can induce pathological cardiac hypertrophy and failure. The roles of miRs in the genesis of physiologic left ventricular hypertrophy (LVH), however, are not well elucidated. OBJECTIVE - To evaluate miRs expression in an experimental model of exercise-induced LVH. METHODS - Male Balb/c mice were divided into sedentary (SED) and exercise (EXE) groups. Voluntary exercise was performed in odometer-monitored metal wheels during 35 days. Analyses were performed after 7 and 35 days of training, and consisted of transthoracic echocardiography, maximal exercise test, miRs microarray (miRBase v.16) and real-time qRT-PCR analysis. RESULTS - Left ventricular weight/body weight ratio increased by 7% in the EXE group at day 7 (p<0.01) and by 11% at 35 days of training (p<0.001) After 7 days of training, microarray identified 35 deregulated miRs: 20 had an increase in their expression and 15 were down-regulated (p=0.01). At day 35 of training, 25 miRs were deregulated: 15 were up-regulated and 10 had decreased their expression compared to the SED group (p<0.01). qRT-PCR confirmed an increase in miR-150 levels at both time points and a decrease in miR-26b, miR-27a and miR-143 after 7 days of voluntary exercise. CONCLUSIONS – We unraveled new miRs that can modulate physiological cardiac hypertrophy, particularly miR-26b, -150, 27a and -143. Our data also indicate that previously established regulatory gene pathways involved in pathological LVH are not deregulated in physiologic LVH. Experimental model of left ventricular hypertrophy induced by voluntary exercise Male Balb/c mice, 8-10 weeks old, 4 groups analyzed, each group consisted of a pool from 4 animals
Project description:Poor maternal nutrition during pregnancy causes intrauterine growth retardation, which, in turn, is associated with increased risk of cardiovascular and metabolic diseases in later life Fetal hearts were collected from baboon fetuses born to regularly fed and undernurished mothers. Total RNA was isolated, and fetal cardiac miRNA were profiled
Project description:The adult vertebrate red spotted newt is a champion of regeneration, demonstrating an amazing ability to regenerate damaged organs and tissues back to an uninjured state without the formation of scar or reduction in function. By developing a novel cardiac resection strategy, our group recently demonstrated that newt hearts could morphologically and functionally regenerate, without scarring, within a period of 2-3 months following injury. MicroRNAs (miRs) have been widely publicized as essential post-transcriptional gene regulators in a variety of biological processes, including regeneration. We have conducted a microarray screen for vertebrate miRs, with several candidate miRs showing significant differential expression at important time-points following injury to the newt heart. The newt microRNA expression between uninjured hearts and regenerating hearts, 7 and 21 days post-injury (dpi), was compared by microarray analysis. Three paired samples were analyzed: Uninjured, 7dpi and 21dpi newt hearts. Three arrays were hybridized comparing two-paired samples each time.
Project description:Using a TWIST1-inducible epithelial-to-mesenchymal transition (EMT) model in HMLE cells, miRNA changes were profiled at different time points during an active EMT. This experiment includes a total of 12 samples consisting of 2 experimental groups at 2 matching time points (day 4, day 12), each with 3 biological repeats: 3 control empty vector samples as controls and 3 inducible TWIST1 samples as the experimental condition.
Project description:UB cells FACS sorted from E15.5 mouse kidneys were analyzed for miRNAs expression. E15.5 UB cells FACS sorted from Rosa26YFP; Hoxb7Cre mice, total RNAs including miRNAs were purified and used for miRNA microarray
Project description:This is the microRNA experiment from the study of ethanol effects on the cultured cell line MCF-7, which is derived from a human malignancy. Cells were cultured in 6 well plates for a period of 4 weeks in the presence or absence of 25 mM ethanol. Cells were washed once with phosphate buffered saline pH 7.4, and RNA was extracted using the Mirvana kit for total RNA extraction. RNA samples were analyzed for microRNA prevalence by LC Sciences of Houston, Tx, USA. The results from 2 separate experiments were normalized and collected as the MultiArray Analysis Data presented here. The miR values are on an arbitrary scale. There are 2 experiments, each containing a control (no ethanol) sample and a sample that was exposed to 25 mM ethanol for 4 weeks.
Project description:Spontaneous paroxysmal atrial fibrillation (PAF) is one of the very common heart rhythm disorders. The molecular mechanisms underlying PAF susceptibility and persistence are multiple and incompletely understood. To study the contribution of microRNAs (miRNAs) to the development and perpetuation of PAF, we used microarray/qPCR analyses to search for changes in miRNA expression in atrial myocardium upon pacing-induced PAF. The miRNA microarray analysis was performed at LC Sciences (Houston, TX, USA). Following screening-microarray, several miRNAs were selected for detailed real-time qPCR assay. Our results suggest that immediate-early miR remodeling of LAA underlies the development and persistence of PAF. A closed-chest model of PAF was established in postnatal pigs via a rapid atrial electrical stimulation with a controlled ventricular response rate. A pacing catheter (delivered into the right atrium via femoral vein access under fluoroscopic guidance) was connected with an external pulse generator for programmed pacing rates. The burst-pacing stimuli were repeated several times, and the induced PAF occurrence rates and durations were recorded. Burst pacing was not performed in sham-operated group. Animals were euthanized 24 hours after cessation of pacing. Given that the right atrium might have been damaged by catheter insertion, we studied miRNA expression changes associated with PAF in the left atrial appendage (LAA) from paced vs control pigs. Six piglet were randomized in two groups, the PAF group (3 replicates) and the sham-control group (3 replicates)