Abstract
Obesity and high fat intake induce alterations in vascular function and structure. Aberrant O-GlcNAcylation (O-GlcNAc) of vascular proteins has been implicated in vascular dysfunction associated with cardiovascular and metabolic diseases. In the present study, we tested the hypothesis that high-fat diet (HFD)-mediated increases in O-GlcNAc-modified proteins contribute to cerebrovascular dysfunction. O-GlcNAc-protein content was increased in arteries from male Wistar rats treated with a HFD (45% fat) for 12 weeks compared with arteries from rats on control diet (CD). HFD augmented body weight [(g) 550± 10 compared with 502± 10 CD], increased plasma triacylglycerols [(mg/dl) 160± 20 compared with 95± 15 CD] and increased contractile responses of basilar arteries to serotonin [5-hydroxytryptamine (5-HT)] [(pD2) 7.0± 0.1 compared with 6.7±0.09 CD] and the thromboxane analogue 9,11-dideoxy-9α,11α-methanoepoxy prostaglandin F2α (U-46619) [(pD2) 7.2± 0.1 compared with 6.8± 0.09 CD]. Of importance, increased levels of O-GlcNAc [induced by 24 h-incubation of vessels with a potent inhibitor of O-GlcNAcase (OGA), O-(2-acetamido-2-deoxy-D-glucopyranosylidene)amino-N-phenylcarbamate (PugNAc)] increased basilar artery contractions in response to U-46619 [(pD2) 7.4± 0.07 compared with 6.8± 0.08 CD] and 5-HT [(pD2) 7.5± 0.06 compared with 7.1± 0.1 CD]. Vessels from rats on the HFD for 12 weeks and vessels treated with PugNAc displayed increased phosphorylation of p38 (Thr180/182) and extracellular signal-regulated kinase 1/2 (Erk1/2) (Ser180/221). Increased 5HT-induced contractions in arteries from rats on the HFD or in arteries incubated with PugNAc were abrogated by mitogen-activated protein kinase (MAPK) inhibitors. Our data show that HFD augments cerebrovascular O-GlcNAc and this modification contributes to increased contractile responses and to the activation of the MAPK pathway in the rat basilar artery.
Original language | English (US) |
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Pages (from-to) | 871-880 |
Number of pages | 10 |
Journal | Clinical Science |
Volume | 130 |
Issue number | 11 |
DOIs | |
State | Published - 2016 |
Keywords
- Basilar artery
- Cerebral artery
- High fat
- O-GlcNAc
- Vascular contraction
ASJC Scopus subject areas
- Medicine(all)