Banca de QUALIFICAÇÃO: FELIPE FERNANDES CORREIA
Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.DISCENTE : FELIPE FERNANDES CORREIA
DATA : 31/07/2019
HORA: 14:00
LOCAL: dados da sala: Sala S17, Terreo, Bl. Delta, Campus SBC, Alam. da Universidade. s/n, B. Anchieta - S. Bernardo do Campo - SP.
TÍTULO:
FUNCTIONAL CONSEQUENCES OF EZH2 EPIGENETICAL REGULATION IN THE NEURODEGENERATION AND LOCOMOTOR AFTER SPINAL CORD INJURY
PÁGINAS: 57
GRANDE ÁREA: Ciências Biológicas
ÁREA: Fisiologia
SUBÁREA: Fisiologia de Órgãos e Sistemas
ESPECIALIDADE: Neurofisiologia
RESUMO:
Spinal cord injury (SCI) is a traumatic neurologic disorder with clinical relevance due to the disruption of neuronal communication between the central nervous system (CNS) and peripheral nervous system. After the primary injury, often caused by mechanical trauma, the condition could aggravate by local tissue inflammation. Nowadays, it is already known that epigenetic-related processes contribute to the spread of CNS damage. Epigenetic regulation is often related to alterations in the chromatin structure, which are capable to change the genetic information, and includes histone acetylation and methylation. Within this context, global methylation and especially the methylation on lysine 27 of histone 3 produced by Enhancer of Zeste Homolog 2 (EZH2) was related to modulation of the inflammatory response and cellular death in CNS infections. However, the role of EZH2 after the neuronal injury is not well described. The aim of this project was to evaluate the role of EZH2 activity on inflammation progress and tissue regeneration through pharmacology inhibition and knockdown of EZH2 gene expression. To this end, we combined immunofluorescence (IF) analyses and western blotting (WB) with motor function evaluation as provided by Basso, Beattie, and Bresnahan (BBB) test and grid scale. Results were compared by student test T or two-way repeated measures ANOVA followed by appropriate posthoc test. All procedures were conducted in accordance with CEUA (2066300916). EZH2 is present on mature cells of the spinal cord and after trauma, it translocates to the nucleus (0.4 ± 0.09 vs. 0.115 ± 0.05, P<0.05), despite protein levels alterations. Furthermore, IF results in sections of the spinal cord revealed that after acute SCI (24h after injury) the number of CD86 positive cells changes in the white matter. When compared to controls (only vehicle) the treatment with GSK343 increases the number of CD86-positive cells (588 ± 251 vs. 1298±150; N= 5; P<0.01), while the pixel intensity analysis demonstrated a reduction on individual bright of this marker (15.5 ± 2.7 vs. 7.8 ± 1.3; N= 5; P<0.01). Moreover, when compared to controls, GSK343 treatment after SCI increased the score in BBB test 6 weeks after injury (7.28±1.68 vs. 14.55±2.25; N= 9; P<0.05), grid scale (0.0% ±33.3 vs. 83.33% ±36.07 vs.; N= 6; P<0.05) and subBBB scale (4.28±1.04 vs. 7.88±1.50; N= 9; P<0.05). IF results evidenced that when compared to controls, the pixel intensity of growth associated protein 43 (GAP43) is higher in the rostral region of the spinal cord after 6 weeks (8.64 ± 0.05 vs. 17.3±1.95; N=3; P>0.01). Also, the GSK343-treated animals presented a tendency towards increased remyelination and glial scar formation. All these data suggest the participation of EZH2 in the immunological innate response, especially in the control of CD86 expression. As a consequence, the presence of EZH2 may influence the adaptive response, which is related to the axonal regeneration and motor function recovery.
MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1675708 - DANIELE RIBEIRO DE ARAUJO
Membro Titular - Examinador(a) Externo ao Programa - 3066269 - VINICIUS DE ANDRADE OLIVEIRA
Membro Titular - Examinador(a) Externo à Instituição - LÚCIA MARIA ARMELIN CORREA - UNIFESP
Membro Suplente - Examinador(a) Interno ao Programa - 2605490 - SERGIO DAISHI SASAKI
Membro Suplente - Examinador(a) Externo ao Programa - 1872537 - MARCELA BERMUDEZ ECHEVERRY