In-ovo feeding with creatine monohydrate: implications for chicken energy reserves and breast muscle development during the pre-post hatching period

The most dynamic period throughout the lifespan of broiler chickens is the pre-post-hatching period, entailing profound effects on their energy status, survival rate, body weight, and muscle growth. Given the significance of this pivotal period, we evaluated the effect of in-ovo feeding (IOF) with creatine monohydrate on late-term embryos’ and hatchlings’ energy reserves and post-hatch breast muscle development. The results demonstrate that IOF with creatine elevates the levels of high-energy-value molecules (creatine and glycogen) in the liver, breast muscle and yolk sac tissues 48 h post IOF, on embryonic day 19 (p < 0.03). Despite this evidence, using a novel automated image analysis tool on day 14 post-hatch, we found a significantly higher number of myofibers with lower diameter and area in the IOF creatine group compared to the control and IOF NaCl groups (p < 0.004). Gene expression analysis, at hatch, revealed that IOF creatine group had significantly higher expression levels of myogenin (MYOG) and insulin-like growth factor 1 (IGF1), related to differentiation of myogenic cells (p < 0.01), and lower expression of myogenic differentiation protein 1 (MyoD), related to their proliferation (p < 0.04). These results imply a possible effect of IOF with creatine on breast muscle development through differential expression of genes involved in myogenic proliferation and differentiation. The findings provide valuable insights into the potential of pre-hatch enrichment with creatine in modulating post-hatch muscle growth and development

A comparative analysis of high-throughput platforms for validation of a circulating microRNA signature in diabetic retinopathy

MicroRNAs are now increasingly recognized as biomarkers of disease progression. Several quantitative real-time PCR (qPCR) platforms have been developed to determine the relative levels of microRNAs in biological fluids. We systematically compared the detection of cellular and circulating microRNA using a standard 96-well platform, a high-content microfluidics platform and two ultra-high content platforms. We used extensive analytical tools to compute inter- and intra-run variability and concordance measured using fidelity scoring, coefficient of variation and cluster analysis. We carried out unprejudiced next generation sequencing to identify a microRNA signature for Diabetic Retinopathy (DR) and systematically assessed the validation of this signature on clinical samples using each of the above four qPCR platforms. The results indicate that sensitivity to measure low copy number microRNAs is inversely related to qPCR reaction volume and that the choice of platform for microRNA biomarker validation should be made based on the abundance of miRNAs of interest

A miR-19 regulon that controls NF-κB signaling

Fine-tuning of inflammatory responses by microRNAs (miRNAs) is complex, as they can both enhance and repress expression of pro-inflammatory mediators. In this study, we investigate inflammatory responses following global miRNA depletion, to better define the overall contribution of miRNAs to inflammation. We demonstrate that miRNAs positively regulate Toll-like receptor signaling using inducible Dicer1 deletion and global miRNA depletion. We establish an important contribution of miR-19b in this effect, which potentiates nuclear factor-κB (NF-κB) activity in human and mouse cells. Positive regulation of NF-κB signaling by miR-19b involves the coordinated suppression of a regulon of negative regulators of NF-κB signaling (including A20/Tnfaip3, Rnf11, Fbxl11/Kdm2a and Zbtb16). Transfection of miR-19b mimics exacerbated the inflammatory activation of rheumatoid arthritis primary fibroblast-like synoviocytes, demonstrating its physiological importance in the pathology of this disease. This study constitutes, to our knowledge, the first description of a miR-19 regulon that controls NF-κB signaling, and suggests that targeting this miRNA and linked family members could regulate the activity of NF-κB signaling in inflammation