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Cytochrome P450 enzymes (CYPs) are involved in phase I of metabolism of many xenobiotics, including drugs. The CYPs belonging to the family 2 are known to be responsible for about 20% of the total drugs metabolism and it underlines the importance of understanding the structural properties of these enzymes in correlation with their biological functions. This paper compares structural properties of the members of subfamily 2C of the human cytochrome P450: CYP2C8, CYP2C9 and CYP2C19. It also analyzes the effects of point mutations corresponding to polymorphic variants of these enzymes on the local hydrophobicity and flexibility of the proteins chains. The three enzymes share high sequence identities, similar global physicochemical properties and a high resemblance of their global spatial structures. Despite their global structural similarity, there are local conformational differences concerning the binding sites with direct consequences on the specificity of every enzyme. The genetic polymorphism of the cytochromes belonging to the subfamily 2C is reflected by some amino acid mutations that significantly affect the local hydrophobicity and/or flexibility of the proteins chains and resulting in their poor ability to metabolize some drug or prodrug compounds. [ABSTRACT FROM AUTHOR]

Parkinson’s disease (PD) is one of the most common and investigated neurodegenerative disorders, the molecular pathology of which is still not fully understood. Excepting the minority of monogenic forms of PD, there are no reliable diagnostic, prognostic and therapy evaluation biomarkers available. Furthermore, basically all PD-related mRNA molecules have been shown to be modulated by microRNAs, substantiating the role of microRNAs in PD pathogenic processes like mitochondrial damage, programmed cell death, and autophagy. The studies attempting to characterize the profile of circulant microRNAs associated to PD have shown a wide variety of data, quite often contradictory, most probably due to the heterogeneity of the disease and the differences in the technical platforms have been used to analyze the different fractions of the blood. Here we describe a two-step qRT-PCR biomarker analysis of plasma microRNAs associated with PD, based on PCR array (discovery step) and TaqMan assays (validation step) and propose a set of 5 plasma microRNAs as being specifically associated with PD. We show data validating three of these microRNAs not only as putative diagnostic biomarkers, but also as therapy-monitoring markers in a cohort of patients diagnosed with sporadic PD. Furthermore, we combine miRWalk machine learning prediction algorithms with clustering and topological community detection (CTCD) approach to describe the signaling pathways putatively targeted by the changes in the expression of the three microRNAs in LEVODOPA/CARBIDOPA treated PD patients. [ABSTRACT FROM AUTHOR]

Member of the miR-15 precursor family, mmu-miR-195 is a conserved small non-coding RNA known for its role in cell cycle and cell death/apoptosis regulation. miR-195 is differentially expressed in various organs and tissues of the postnatal mouse. Recent analyses have associated miR-195 with different diseases such as cancer, chronic obstructive pulmonary disease, heart failure, Parkinson disease. We evaluated the expression of the mature and precursor mmu-miR-195 in the heart of male and female, wild-type mice at different stages of pre-natal and post-natal life. Quantitative Real-Time PCR (qRT-PCR) analysis revealed coordinated, concordant changes of the mature form, which are not paralleled by the pri-miRNA changes. Furthermore, we used a combined machine learning algorithm for miR targets prediction, and a clustering and topological community detection (CTCD) approach followed by gene ontology analysis to describe the impact of miR-195 changes upon heart transcriptome. We show that miR-195 regulates multiple novel signaling pathways associated with cardiac maturation and provide data validating - both at mRNA and protein level – our predictions. [ABSTRACT FROM AUTHOR]

Background. Saliva sampling is a non-invasive, cheap, easy-to-access alternative to traditional tissue and blood sampling. Saliva is an accurate indicator of bodily conditions, and salivary biomarkers may serve as early diagnostic tools. In this study we aimed to validate the salivary expression of a panel of 5 microRNAs, identified from a literature screen as potential noninvasive biomarkers for oral squamous cell carcinoma (OSCC) diagnosis, prediction and therapy monitoring. Materials and methods. The research subjects included patients diagnosed with oral squamous cell carcinoma hospitalized at the Clinic of Oral & Maxillofacial Surgery in Timişoara. The biological samples (saliva) were collected from the patients before the biopsy procedure. We included in this study a group of 4 patients and a control group of 4 individuals without OSCC. For microRNA quantification, we performed reverse transcription using the TaqMan® MicroRNA Reverse Transcription Kit (Thermofisher) followed by quantitative Real-Time PCR (qRTPCR) using TaqMan™ MicroRNA Assays (Thermofisher); all qRT-PCR reactions were performed in triplicate. Results. With the exception of miR-181b, all the investigated microRNAs were found to have deregulated expression in OSCC patients' saliva. Hsa-miR-137 was found to be up-regulated in the saliva of OSCC patients while hsa-miR-205 was found to be strongly down-regulated. However, we were able to confirm the activation of expression of hsa-miR-127-5b and the strong repression of hsa-miR-375 in the saliva of OSCC patients. The data upon hsa-miR-181 expression in OSCC have been conflicting, ranging from strong down-regulation in tissue samples and possible usage as therapeutic tool to correlation with metastasis propensity; however, we have not detected changes in the expression levels in saliva. Conclusions. Detection of deregulated miRNA biomarkers in saliva samples is a promising noninvasive assay for risk assessment of oral malignancy, which may add value to the histologic diagnosis. [ABSTRACT FROM AUTHOR]