High plasma C-reactive protein (CRP) is related to low paraoxonase-I (PON-I) activity independently of high leptin and low adiponectin in type 2 diabetes mellitus.
OBJECTIVE
In type 2 diabetes mellitus, circulating C-reactive protein (CRP) is increased, whereas the high density lipoprotein (HDL)-associated, anti-oxidative and anti-inflammatory enzyme, paraoxonase-I, is decreased. Both high CRP and low paraoxonase-I activity may predict cardiovascular disease. It is unknown whether lower paraoxonase-I activity contributes to higher CRP levels in diabetes. In type 2 diabetic and control subjects, we determined the relationship of CRP with paraoxonase-I when taking account of plasma levels of pro- and anti-inflammatory adipokines.


METHODS
In 81 type 2 diabetic patients and 89 control subjects, plasma high-sensitive CRP, serum paraoxonase-I activity (arylesterase activity, assayed as the rate of hydrolysis of phenyl acetate into phenol), plasma leptin, adiponectin, resistin and lipids were determined.


RESULTS
Body mass index (BMI), waist, insulin resistance, triglycerides, CRP, leptin and resistin levels were higher (P < 0.05 to P < 0.001), whereas HDL cholesterol, paraoxonase-I activity and adiponectin levels were lower (P = 0.02 to P < 0.001) in diabetic compared to control subjects. Multiple linear regression analysis demonstrated that, after controlling for age and gender, CRP was inversely related to paraoxonase-I activity (beta = -0.15, P = 0.028) and adiponectin (beta = -0.18, P = 0.009), and positively to leptin (beta = 0.33, P < 0.001) and BMI (beta = 0.22, P = 0.007), independently of the diabetic state (or of fasting glucose or HbA1c), insulin resistance and lipids (P > 0.20 for all).


CONCLUSIONS
Low paraoxonase-I activity is related to higher CRP, independently of adipokines, as well as of obesity and lipids. Low paraoxonase-I activity in type 2 diabetes mellitus may contribute to increased cardiovascular risk via an effect on enhanced systemic low-grade inflammation.
Dullaart
Robin P F
RP
Department of Endocrinology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands. r.p.f.dullaart@int.umcg.nl
de Vries
Rindert
R
Sluiter
Wim J
WJ
Voorbij
Hieronymus A M
HA
D052242:Adiponectin / Q000097:blood*; D000368:Aged; D043303:Aryldialkylphosphatase / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000453:epidemiology; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D020738:Leptin / Q000097:blood*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D052243:Resistin / Q000097:blood; D012307:Risk Factors
D052242:Adiponectin; D020738:Leptin; D052243:Resistin; D002097:C-Reactive Protein; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human