Contributions
Abstract: P1010
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 17 Environmental factors
Background: The susceptibility to multiple sclerosis (MS) is regulated by a set of genetic, environmental and epigenetic factors. Among the environmental factors, the infection by Epstein-Barr virus (EBV), tobacco consumption and Vitamin D levels are critical for the disease onset. Cellular microRNAs (miRNAs), as an epigenetic mechanism, regulate several biological processes and have been widely studied in MS. Epstein-Barr virus encodes for 44 miRNAs that could exert their function by controlling the expression of cellular genes. The aim of this study was to investigate the relationship between the environmental factors of MS susceptibility.
Methods: Plasma was collected from a total of 70 Caucasian individuals positive for EBNA-1 IgG, including 30 relapse-onset MS patients and 40 controls. The proportion of women in the whole set of samples was 63.33%, and 67.5% in MS group. miRNAs were extracted from plasma using the mirVana™ PARIS™ RNA miRNA kit and quantified by qRT-PCR. Levels of 25-OH Vitamin D were assessed by electrochemiluminiscence and classified into deficiency (0-30 ng/ml) and adequacy (>30 ng/ml). Furthermore, tobacco smoking status was appropriately registered. Main differences in ebv-miRNAs expression were determined by U Mann-Whitney.
Results: A set of 14 EBV miRNAs was accurately selected and analyzed for the study. We found that ebv-miR-BART22 was detectable in 77.14% plasma samples. When we analyzed the expression of ebv-miR-BART22 depending on the levels of Vitamin D, no significant differences were found (p=0.489).
Otherwise, we reported an increase of ebv-miR-BART22 levels (p=0.020) in smokers in both controls and MS patients. When sample was stratified by sex, only female smokers showed an up-regulation of ebv-miR-BART22 (p=0.004) in contrast to male (p=0.645). Analyzing groups separately, MS patients presented ebv-miR-BART22 overexpression in smoker patients (p=0.035) but we did not find such effect when controls were studied (p=0.318). In particular, MS female smokers showed higher ebv-miR-BART22 expression (p=0.038) but this fact did not occur in males (p=0.383).
Conclusions: These results presented herein pointed out an overexpression of ebv-miR-BART22 in women diagnosed with MS who smoked tobacco. However, further research must be addressed in order to determine the underlying mechanisms altered by tobacco consumption and EBV in the pathogenesis of MS.
Disclosure:
Muñoz-San Martín M reports no disclosures.
Blay J reports no disclosures.
Robles-Cedeño R reports no disclosures.
Tomàs-Roig J reports no disclosures.
Gómez I reports no disclosures.
Perkal H reports no disclosures.
Quintana E reports no disclosures.
Ramió-Torrentà Ll has received compensation for consulting services and speaking honoraria from Biogen Idec, Novartis, Bayer, Merck-Serono, Genzyme, Teva Pharmaceutical Industries Ltd and Almirall.
Abstract: P1010
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 17 Environmental factors
Background: The susceptibility to multiple sclerosis (MS) is regulated by a set of genetic, environmental and epigenetic factors. Among the environmental factors, the infection by Epstein-Barr virus (EBV), tobacco consumption and Vitamin D levels are critical for the disease onset. Cellular microRNAs (miRNAs), as an epigenetic mechanism, regulate several biological processes and have been widely studied in MS. Epstein-Barr virus encodes for 44 miRNAs that could exert their function by controlling the expression of cellular genes. The aim of this study was to investigate the relationship between the environmental factors of MS susceptibility.
Methods: Plasma was collected from a total of 70 Caucasian individuals positive for EBNA-1 IgG, including 30 relapse-onset MS patients and 40 controls. The proportion of women in the whole set of samples was 63.33%, and 67.5% in MS group. miRNAs were extracted from plasma using the mirVana™ PARIS™ RNA miRNA kit and quantified by qRT-PCR. Levels of 25-OH Vitamin D were assessed by electrochemiluminiscence and classified into deficiency (0-30 ng/ml) and adequacy (>30 ng/ml). Furthermore, tobacco smoking status was appropriately registered. Main differences in ebv-miRNAs expression were determined by U Mann-Whitney.
Results: A set of 14 EBV miRNAs was accurately selected and analyzed for the study. We found that ebv-miR-BART22 was detectable in 77.14% plasma samples. When we analyzed the expression of ebv-miR-BART22 depending on the levels of Vitamin D, no significant differences were found (p=0.489).
Otherwise, we reported an increase of ebv-miR-BART22 levels (p=0.020) in smokers in both controls and MS patients. When sample was stratified by sex, only female smokers showed an up-regulation of ebv-miR-BART22 (p=0.004) in contrast to male (p=0.645). Analyzing groups separately, MS patients presented ebv-miR-BART22 overexpression in smoker patients (p=0.035) but we did not find such effect when controls were studied (p=0.318). In particular, MS female smokers showed higher ebv-miR-BART22 expression (p=0.038) but this fact did not occur in males (p=0.383).
Conclusions: These results presented herein pointed out an overexpression of ebv-miR-BART22 in women diagnosed with MS who smoked tobacco. However, further research must be addressed in order to determine the underlying mechanisms altered by tobacco consumption and EBV in the pathogenesis of MS.
Disclosure:
Muñoz-San Martín M reports no disclosures.
Blay J reports no disclosures.
Robles-Cedeño R reports no disclosures.
Tomàs-Roig J reports no disclosures.
Gómez I reports no disclosures.
Perkal H reports no disclosures.
Quintana E reports no disclosures.
Ramió-Torrentà Ll has received compensation for consulting services and speaking honoraria from Biogen Idec, Novartis, Bayer, Merck-Serono, Genzyme, Teva Pharmaceutical Industries Ltd and Almirall.