2-THE N6-METHYLADENOSINE READER YTHDF2 REGULATES THE LNCRNA TCONS_00006193 TO CONTROL SMOOTH MUSCLE CELL PROLIFERATION VERSUS QUIESCENCE
de la Cruz-Thea B1, Peinado VI2, Ho XH3, Volpini X1, Meister G3, Musri MM1,4,5
1Instituto de Investigación Médica M y M Ferreyra (INIMEC-CONICET-UNC), Córdoba, Argentina, 2Department of Pulmonary Diseases Hospital Clinic, Barcelona, Spain, 3RNA Biology, Facultät VorKlinikum and Medizin, Universität Regensburg, Germany, 4 Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Argentina, 5Instituto Universitario de Ciencias Biomédicas Córdoba (IUCBC), Córdoba, Argentina.
Smooth muscle cells (SMC) are an essential component of the arterial wall. SMC display an intrinsic phenotypic plasticity that allow them to change between a quiescent, contractile or differentiated state with high expression of SMC specific proteins, to a de-differentiated, proliferative and migratory state in response to micro-environmental cues. SMC phenotypic plasticity alteration constitutes a key factor in the onset of cardiovascular diseases. It has been shown that long non-coding RNAs (lncRNAs) regulates a number of physiological and pathological processes, but little is known about these molecules in SMC biology. Our aim was to identify and evaluate the role of lncRNAs in SMC phenotypic switch. We used an in vitro model of human SMC differentiation and a number of biochemist and molecular biology tools, including RNA deep sequencing (Illumina Seq), specific candidate knock down by siPool-RNA and gene expression evaluation by quantitative PCR, western blot and northern blot. Our results show a number of lncRNAs that significantly change expression during SMC differentiation. Among them, the lncRNA4 (TCONS_00006193) is almost not detected in proliferative SMC and its levels increases significanlty in quiescent-differentiated cells. LncRNA4 knockdown leads to both differentiation defects and increased SMC proliferation. Interestingly, we found that the N6-methyladenosine (m6A) reader YTHDF2, which target specific RNAs to degradation, regulates post-transcriptionally lncRNA4 expression. M6A is the most abundant internal RNA modification that controls RNA metabolism and function. We conclude that lncRNA4 and YTHDF2 have key functions in SMC homeostasis and might have a role in the development of cardiovascular diseases.
3-SEXUAL DIMORPHISM IN BLOOD PRESSURE REGULATION DURING ANG II INFUSION:
INVOLVEMENT OF SEX CHROMOSOME COMPLEMENT AND HORMONAL EFFECTS
Dadam, Florencia1; Vivas, Laura1,2; Caeiro, Ximena E1.
1Instituto de Investigación Médica M. y M. Ferreyra, INIMEC-CONICET-Universidad Nacional Córdoba.
2Catedra de Fisiologia Animal, Facultad de Ciencia Exactas, Fisicas y Naturales-Universidad Nacional de Corodoba. e-mail: mariafdadam@gmail.com; xcaeiro@immf.uncor.edu
The pressor response to Ang II infusion is sexually dimorphic under physiological and pathophysiological circumstances. But why do male and female show differences in rennin angiotensin system (RAS) activation and inhibition? Sex steroids can induce organizational (long-lasting or permanent) effect during critical periods of development but can also impart (temporary or reversible) activational effects. Furthermore, males and females also carry different sex chromosome complements (SCC:XY/XX) and thus are influenced throughout life by different genomes.
In the present study we evaluated the involvement of SCC, organizational and activational hormonal effects on changes in mean arterial pressure (MAP) in a 10 min Ang II infusion protocol. For this purpose, we used gonadectomized (GDX) mice of the "four core genotype" model, in which the effect of gonadal sex and SCC is dissociated, allowing comparisons of sexually dimorphic traits between XX and XY females as well as in XX and XY males. For hormonal replacement experiments GDX mice were daily injected with ß-estradiol (E2) or testosterone propionate (TP) (2ug/g) for a 4 day period.
The statistical analysis reveal an interaction of SCC, organizational and activational hormonal effect during Ang II infusion {F(7,39=2,60 p<0,01)}. In GDX mice without hormonal replacement, Ang II infusion resulted in an increase in MAP in XX-male, XX/XY-female mice, while no changes were observed in XY-male mice. Furthermore, β-estradiol replacement (E2) resulted in a decrease in blood pressure in XX-male, XX/XY-female (indicating an activational β-estradiol effect) however no changes were observed in XY-male group. Moreover testosterone propionate replacement showed a greater increase in blood pressure in XY-male mice when compared to XX-male and XX-female/GDX-TP groups; demonstrating an activational hormonal effect of testosterone in XY-male mice. Thus, our data demonstrate the contribution and interaction of SCC, activational and organizational hormonal effects in sex differences in Ang II-blood pressure regulation.
meostasis and might have a role in the development of cardiovascular diseases.
4-SEX-FRAILTY DIFFERENCES IN AGING MICE: NEUROPATHOLOGIES AND THERAPEUTIC PROJECTIONS
Herrera, MLab, Basmadjian, OMa, Falomir-Lockhart, Eb, Dolcetti, FJCab, Hereñú, CBa* and Bellini, MJb*
a. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacología. Instituto de Farmacología Experimental Córdoba (IFEC-CONICET).Córdoba, Argentina.
b. Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP-CONICET).Buenos Aires, Argentina.
* equally contribution
In the present study, we evaluate possible frailty predictors in older mice in a sex-specific manner. We also observe the effects of IGF-1 gene therapy and its correlation with the expression of these frailty and emotionality. In order to evaluate frailty index we employed two different approaches, we perform a frailty assessment through a 31-Item Clinical Frailty Index and through a Performance-Based Eight-Item Frailty Index. Both indexes are in concordance to evaluate sex differences, but they do not correlate when evaluating IGF-1 therapy effects. Moreover, to reduced test-to-test variability for measures of dependent variables, in this aging model we compared open field results across studies of sex and treatment evaluation using z-score normalization. Our data show that regular open field parameters submitted to Z-score normalization analysis could be a useful tool to identify sex differences in aging mice after growth factors therapies. Considering that gender is a factor that influences the incidence and/or nature of all major complex diseases, our work is one of the first ones that compares the use of different frailty indices calculations to identify sex differences and therapy efficiency in aging models, specifically by the use of noninvasive therapeutical strategies.
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