Synthetic α-Tocopherol, Compared with Natural α-Tocopherol, Downregulates Myelin Genes in Cerebella of Adolescent Ttpa-null Mice.
RRR α-tocopherol
Ttpa-null mouse
RNA-sequencing
adolescent
all-rac α-tocopherol
brain
gene expression
myelin
vitamin E
Journal
The Journal of nutrition
ISSN: 1541-6100
Titre abrégé: J Nutr
Pays: United States
ID NLM: 0404243
Informations de publication
Date de publication:
01 05 2020
01 05 2020
Historique:
received:
10
09
2019
revised:
01
10
2019
accepted:
09
12
2019
pubmed:
29
12
2019
medline:
17
9
2020
entrez:
29
12
2019
Statut:
ppublish
Résumé
Vitamin E (α-tocopherol; α-T) deficiency causes spinocerebellar ataxia. α-T supplementation improves neurological symptoms, but little is known about the differential bioactivities of natural versus synthetic α-T during early life. We assessed the effects of dietary α-T dose and source on tissue α-T accumulation and gene expression in adolescent α-tocopherol transfer protein-null (Ttpa-/-) mice. Three-week-old male Ttpa-/- mice (n = 7/group) were fed 1 of 4 AIN-93G-based diets for 4 wk: vitamin E deficient (VED; below α-T limit of detection); natural α-T, 600 mg/kg diet (NAT); synthetic α-T, 816 mg/kg diet (SYN); or high synthetic α-T, 1200 mg/kg diet (HSYN). Male Ttpa+/+ littermates fed AIN-93G [75 mg synthetic α-T (CON)] served as controls (n = 7). At 7 wk of age, tissue α-T concentrations and stereoisomer profiles were measured for all groups. RNA-sequencing was performed on cerebella of Ttpa-/- groups. Ttpa-/- mice fed VED had undetectable brain α-T concentrations. Cerebral cortex α-T concentrations were greater in Ttpa-/- mice fed NAT (9.1 ± 0.7 nmol/g), SYN (10.8 ± 1.0 nmol/g), and HSYN (13.9 ± 1.6 nmol/g) compared with the VED group but were significantly lower than in Ttpa+/+ mice fed CON (24.6 ± 1.2 nmol/g) (P < 0.001). RRR-α-T was the predominant stereoisomer in brains of Ttpa+/+ mice (∼40%) and Ttpa-/- mice fed NAT (∼94%). α-T stereoisomer composition was similar in brains of Ttpa-/- mice fed SYN and HSYN (2R: ∼53%; 2S: ∼47%). Very few of the 16,774 genes measured were differentially expressed. However, compared with the NAT diet, HSYN significantly downregulated 20 myelin genes, including 2 transcription factors: SRY-box transcription factor 10 (Sox10) and myelin regulatory factor (Myrf), and several downstream target genes (false discovery rate <0.05). High-dose synthetic α-T compared with natural α-T alters myelin gene expression in the adolescent mouse cerebellum, which could lead to morphological and functional abnormalities later in life.
Sections du résumé
BACKGROUND
Vitamin E (α-tocopherol; α-T) deficiency causes spinocerebellar ataxia. α-T supplementation improves neurological symptoms, but little is known about the differential bioactivities of natural versus synthetic α-T during early life.
OBJECTIVE
We assessed the effects of dietary α-T dose and source on tissue α-T accumulation and gene expression in adolescent α-tocopherol transfer protein-null (Ttpa-/-) mice.
METHODS
Three-week-old male Ttpa-/- mice (n = 7/group) were fed 1 of 4 AIN-93G-based diets for 4 wk: vitamin E deficient (VED; below α-T limit of detection); natural α-T, 600 mg/kg diet (NAT); synthetic α-T, 816 mg/kg diet (SYN); or high synthetic α-T, 1200 mg/kg diet (HSYN). Male Ttpa+/+ littermates fed AIN-93G [75 mg synthetic α-T (CON)] served as controls (n = 7). At 7 wk of age, tissue α-T concentrations and stereoisomer profiles were measured for all groups. RNA-sequencing was performed on cerebella of Ttpa-/- groups.
RESULTS
Ttpa-/- mice fed VED had undetectable brain α-T concentrations. Cerebral cortex α-T concentrations were greater in Ttpa-/- mice fed NAT (9.1 ± 0.7 nmol/g), SYN (10.8 ± 1.0 nmol/g), and HSYN (13.9 ± 1.6 nmol/g) compared with the VED group but were significantly lower than in Ttpa+/+ mice fed CON (24.6 ± 1.2 nmol/g) (P < 0.001). RRR-α-T was the predominant stereoisomer in brains of Ttpa+/+ mice (∼40%) and Ttpa-/- mice fed NAT (∼94%). α-T stereoisomer composition was similar in brains of Ttpa-/- mice fed SYN and HSYN (2R: ∼53%; 2S: ∼47%). Very few of the 16,774 genes measured were differentially expressed. However, compared with the NAT diet, HSYN significantly downregulated 20 myelin genes, including 2 transcription factors: SRY-box transcription factor 10 (Sox10) and myelin regulatory factor (Myrf), and several downstream target genes (false discovery rate <0.05).
CONCLUSIONS
High-dose synthetic α-T compared with natural α-T alters myelin gene expression in the adolescent mouse cerebellum, which could lead to morphological and functional abnormalities later in life.
Identifiants
pubmed: 31883016
pii: S0022-3166(22)02172-1
doi: 10.1093/jn/nxz330
doi:
Substances chimiques
Carrier Proteins
0
alpha-tocopherol transfer protein
0
alpha-Tocopherol
H4N855PNZ1
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Langues
eng
Sous-ensembles de citation
IM
Pagination
1031-1040Informations de copyright
Copyright © The Author(s) 2019.