The ribosomal protein L2 in S. cerevisiae controls the level of accumulation of its own mRNA

The expression of the yeast L2 r-protein gene is controlled at the level of mRNA accumulation. The product of the gene appears to participate in this regulation by an autogenous feedback mechanism. This control does not operate at the level of transcription but instead affects L2 mRNA accumulation. This autogenous regulation of mRNA accumulation provides an interesting analogy to the autogenous translational regulation of r-proteins in Escherichia coli

SMA human iPSC-derived motor neurons show perturbed differentiation and reduced miR-335-5P expression

Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by mutations in the Survival Motor Neuron 1 gene, resulting in very low levels of functional Survival of Motor Neuron (SMN) protein. SMA human induced Pluripotent Stem Cells (hiPSCs) represent a useful and valid model for the study of the disorder, as they provide in vitro the target cells. MicroRNAs (miRNAs) are often reported as playing a key role in regulating neuronal differentiation and fate specification. In this study SMA hiPSCs have been differentiated towards early motor neurons and their molecular and immunocytochemical profile were compared to those of wild type cells. Cell cycle proliferation was also evaluated by fluorescence-activated cell sorting (FACS). SMA hiPSCs showed an increased proliferation rate and also higher levels of stem cell markers. Moreover; when differentiated towards early motor neurons they expressed lower levels of NCAM and MN specific markers. The expression of miR-335-5p; already identified to control self-renewal or differentiation of mouse embryonic stem cells (mESCs); resulted to be reduced during the early steps of differentiation of SMA hiPSCs compared to wild type cells. These results suggest that we should speculate a role of this miRNA both in stemness characteristic and in differentiation efficiency of these cells

Control of neoplastic cell proliferation and differentiation by restoration of 4-hydroxynonenal physiological concentrations

Several studies point to the existence of an inverse correlation between cellular lipid peroxidation and both cell proliferation and neoplastic transformation. In anaplastic cell lines products of membrane lipid peroxidation are very low or undetectable. Furthermore numerous results demonstrate effect of lipid peroxidation products on central biochemical pathways and intracellular signalling at physiological concentrations. 4-hydroxynonenal (HNE) is one of the most active products of lipid peroxidation. The restoration of HNE physiological concentrations in neoplastic cells may inhibit cell proliferation and modulate cell re-differentiation. This review try to summarize and critically discuss the effects of physiological concentrations of HNE on normal and neoplastic cell line

The relations between atrial natriuretic factor release and adrenergic activation in hypertrophic cardiomyopathy

Atrial natriuretic factor (ANF) is a potent natriuretic and vasoactive (vasorelaxant) peptide localized in the secretory-like atrial specific granules. The main peptide in this storage granules is the 126 amino acid proatrial natriuretic peptide, but the principal circulating form in human plasma is the 28 amino acid, alpha-human natriuretic peptide. Animal and in vitro studies have suggested that ANF modulates autonomic circulatory control, probably with a dose-dependent mechanism. Moreover, recent human studies have resulted contradictory. In particular, it is still unclear if high circulating levels of ANF, which are present in congestive heart diseases constantly, may be correlated with sympathetic nervous system activity in man. Previously we have shown that in congestive diseases there is a relation between ANF and catecholamine secretion. From these basis, the aim of this study was to investigate on the pathophysiological relations between atrial natriuretic factor (ANF) release and adrenergic activation in patients with obstructive hypertrophic cardiomyopathy (n = 6) and non obstructive hypertrophic cardiomyopathy (n = 4). Sympathetic activation in physiologic way was induced by cycloergometer sub-maximal exercise. Then specimens of venous blood were achieved for plasma determination of ANF and catecholamines pre- and post-exercise. Results have shown that in obstructive hypertrophic cardiomyopathy patients basal levels of ANF and catecholamines were higher than levels of these parameters in non obstructive hypertrophic cardiomyopathy patient

High prevalence of myocardial ischemia and vasoconstrictive hormonal release in hypertension during chronic renal failure

Indexes of myocardial ischemia and vasoconstrictive hormonal release were evaluated in order to investigate the difference between essential hypertension and hypertension during chronic renal failure

Regulation of the p27Kip1 tumor suppressor by miR-221 and miR-222 promotes cancer cell proliferation

MicroRNAs (miRNAs) are potent post-transcriptional regulators of protein coding genes. Patterns of misexpression of miRNAs in cancer suggest key functions of miRNAs in tumorigenesis. However, current bioinformatics tools do not entirely support the identification and characterization of the mode of action of such miRNAs. Here, we used a novel functional genetic approach and identified miR-221 and miR-222 (miR-221&222) as potent regulators of p27Kip1, a cell cycle inhibitor and tumor suppressor. Using miRNA inhibitors, we demonstrate that certain cancer cell lines require high activity of miR-221&222 to maintain low p27Kip1 levels and continuous proliferation. Interestingly, high levels of miR-221&222 appear in glioblastomas and correlate with low levels of p27Kip1 protein. Thus, deregulated expression of miR-221&222 promotes cancerous growth by inhibiting the expression of p27Kip1