Oxidative stress could precede endothelial dysfunction and insulin resistance in Indian Mauritians with impaired glucose metabolism.
OBJECTIVE
To measure oxidative stress, endothelial dysfunction and insulin resistance in Indian Mauritians at different stages of development of Type II (non-insulin-dependent) diabetes mellitus.


METHODS
Plasma total 8-epi-PGF2alpha, an indicator of oxidative stress, was determined in age-matched subjects with normal glucose metabolism (n = 39), impaired glucose tolerance (n = 14), newly diagnosed diabetes (n = 8) and established diabetes (n = 14). Plasma glucose and insulin were measured at baseline and 2 h following an oral glucose tolerance test. Endothelial function was assessed by non-invasive digital pulse wave photoplethysmography.


RESULTS
Plasma 8-epi-PGF2alpha increased in subjects with impaired glucose tolerance (p < 0.05) compared with control subjects, and was even higher in newly diagnosed diabetic patients (p < 0.01) and established (p < 0.01) diabetic patients. A tendency towards reduced endothelial function in subjects with impaired glucose tolerance became significant in patients with newly diagnosed and established diabetes (p < 0.01), and was correlated with 8-epi-PGF2alpha (r = 0.36, p < 0.01). Insulin resistance (homeostasis model assessment) did not change in subjects with impaired glucose tolerance compared with control subjects, but increased in newly diagnosed (p < 0.01) and established (p < 0.001) diabetic subjects. The 8-epi-PGF2alpha was correlated with fasting glucose (r = 0.50, p < 0.001), triglycerides (r = 0.40, p < 0.001) and insulin resistance (r = 0.35, p < 0.001).


CONCLUSIONS
Oxidant stress is an early event in the evolution of Type II diabetes and could precede the development of endothelial dysfunction and insulin resistance.
Gopaul
N K
NK
Department of Experimental Therapeutics, St Bartholomew and the Royal London School of Medicine and Dentistry, Queen Mary, UK.
Manraj
M D
MD
Hébé
A
A
Lee Kwai Yan
S
S
Johnston
A
A
Carrier
M J
MJ
Anggård
E E
EE
D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D015237:Dinoprost / Q000031:analogs & derivatives*; D004730:Endothelium, Vascular / Q000503:physiopathology*; D028441:F2-Isoprostanes / Q000097:blood; D005215:Fasting / Q000097:blood; D005260:Female; D005947:Glucose / Q000378:metabolism*; D018149:Glucose Intolerance; D006801:Humans; D007194:India / Q000208:ethnology; D007333:Insulin Resistance; D008297:Male; D008436:Mauritius; D008875:Middle Aged; D018384:Oxidative Stress; D012016:Reference Values; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D028441:F2-Isoprostanes; D014280:Triglycerides; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost; D005947:Glucose