Objective       To detect the plasma level of C1q/TNF-related protein (CTRP)3 in the healthy

obesity and type 2 diabetes mellitus (T2DM) sub

jects

and investigate the association of plasma CTRP3 level with insulin resistance index and related factors.       Methods        Eighty-eight individuals with normal glucose tolerance (NGT) and eighty-six patients with newly diagnosed T2DM were enrolled in this study. Then they were divided into obese (OB) subgroup and normal weight subgroup (NW) according to their body mass index (BMI) ≥25 kg/m

2

or not. The relationship of plasma CTRP3 level with fasting plasma glucose (FPG)

2h plasma glucose (2hPG)

glycosylated hemoglobin (HbA1c)

fasting insulin (FINS)

lipids and interleukin-6 (IL-6)

BMI

waist-to-hip ratio (WHR) and blood pressure were evaluated. Homeostasis model assessment (HOMA) was used to calculate the insulin resistance index (HOMA-IR=FINS×FPG/22.5). Levels of CTRP3 and IL-6 were detected by ELISA.       Results       The plasma level of CTRP3 was significantly lower in T2DM group than NGT group (369.59±117.56 vs 445.42±124.03 ng/mL

P

0.01)

and the level was also obviously lower in OB subjects than in NW subjects (352.87±106.38 vs 464.29±120.71 ng/mL

P

0.01). Single factor correlation analysis showed that the plasma level of CTRP3 had no correlation with gender

age

blood pressure

TC and LDL-c (

P

0.05)

but had negative correlation with BMI

WC

WHR

FPG

2hPG

HbA1c

TG

FINS

HOMA-IR and IL-6 (

P

0.01)

and positive correlation with HDL-c (

P

0.05). Multiple linear regression showed that HbA1c

TG and HOMA-IR were independently associated with plasma CTRP3 level (

P

0.05).       Conclusion       The plasma level of CTRP3 is significantly lower in both the obese and T2DM patients than normal subjects. CTRP3 is closely associated with obesity

glycolipid disorder

inflammation and insulin resistance. HbA1c

TG and HOMA-IR are independent factors of plasma CTRP3. CTRP3 may contribute to the pathophysiology of obesity and T2DM.