Relations of human carotid atherosclerotic plaque with levels of adiponectin, tumor necrosis factor-a and interleukin-6

Objective To investigate the correlation between levels of adiponectin (APN) and tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and both formation and stability of human carotid atherosclerotic plaques.Methods Forty-eight specimens from patients with carotid atherosclerotic plaques (carotid plaque group),admitted to our hospital from April 2011 to July 2012 and performed carotid endarterectomy,and 25 specimens from patients with superior mesenteric artery and 25 healthy subjects (specimen control group and healthy control group,respectively) were collected in our study.The carotid atherosclerotic plaque specimens were sub-divided into soft plaque group (n=16),mixed plaque group (n=16) and hard plaque group (n=16) according to the results ofCT angiography (CTA).The serum TNF-α and IL-6 levels in the carotid plaque group and the healthy control group were measured by enzyme linked immunosorbent assay (ELISA),and the mRNA and protein expressions of APN in the carotid plaque group and the specimen control group were determined by reverse transcription-polymerase chain reaction(RT-PCR) and Western blotting.Results The levels of serum TNF-α and IL-6 in all patients with carotid atherosclerotic plaques were significantly increased as compared with those in the healthy control group (P＜0.05); those in soft plaque group was significantly higher than those in the hard plaque group (P＜0.05).The mRNA and protein expressions of APN in all patients with carotid atherosclerotic plaque were significantly decreased as compared with those in specimen control group (P＜0.05); soft plaque group exhibited lower mRNA and protein expressions of APN than hard plaque group (P＜0.05); there was a positive correlation between the serum TNF-α and IL-6 levels in the carotid plaque group (r=0.810,P=0.000); there was negative correlation between the levels of serum TNF-α and IL-6 and the protein expression of APN in the carotid plaque group (r=-0.760,P=0.000; r=-0.519,P=0.007,respectively).Conclusion APN,TNF-α and IL-6 are likely to participate in the formation and stability of human carotid atherosclerotic plaques. Key words: Atherosclerotic plaque;  Carotid;  Adiponectin;  Tumor necrosis factor-α; Interleukin-6