Plasma visfatin levels are positively associated with circulating interleukin-6 in apparently healthy Korean women.

Even though visfatin has been suggested as a proinflammatory adipokine, there are few studies of the relationship between plasma visfatin concentrations and proinflammatory markers in the nondiabetic population. We showed that plasma visfatin concentrations were positively associated with circulating interleukin-6 levels and diastolic blood pressure independent of obesity in nondiabetic healthy Korean women. These results suggest that circulating visfatin may be related with some proinflammatory condition even in a nondiabetic state.

Prevalence of prehypertension and hypertension in a Korean population: Korean National Health and Nutrition Survey 2001.

OBJECTIVE: The present study aimed to determine the prevalence of prehypertension and hypertension, and their association with the risk factors in a Korean population. DESIGN: The Korean Nation Health and Nutrition Survey 2001, a cross-sectional survey, was a nationally representative survey in which a stratified multistage sampling design was used. METHODS: Data from a comprehensive questionnaire, together with a physical examination and blood sample, were obtained from 6074 Korean adults (2620 men and 3454 women) aged > or = 20 years, and analysed. RESULTS: The estimated age-adjusted prevalence of hypertension and prehypertension was 22.9% (26.9% in men, 20.5% in women) and 31.6% (41.9% in men, 25.9% in women), respectively, in the Korean population according to Joint National Committee 7 criteria. Multivariate analysis revealed that age, gender, body mass index, fasting plasma glucose, total-cholesterol and alcohol consumption were significantly associated with hypertension. Overall, only 30.2% of the hypertensive individuals had been previously diagnosed. Furthermore, 22.9% of the hypertensive individuals were being treated with antihypertensive medication, but only 10.7% had their blood pressure adequately controlled. The rates of awareness, treatment and control were higher for the women than for the men, and these rates increased with age. CONCLUSION: Hypertension and prehypertension are common in Korea, and more than one-half of the hypertensive patients have not been diagnosed. These results place great emphasis on the urgent need for a public health program to improve the detection, prevention and treatment of hypertension and prehypertension.

Effect of rosiglitazone on plasma adiponectin levels and arterial stiffness in subjects with prediabetes or non-diabetic metabolic syndrome.

OBJECTIVE: Thiazolidinediones have favorable influences on surrogate markers of atherosclerosis such as adiponectin, and arterial stiffness in diabetic patients. However, it is not well known whether these beneficial effects occur in subjects without diabetes, such as prediabetes or the non-diabetic metabolic syndrome (MetS). The present study was therefore designed to evaluate the effectiveness of the insulin-sensitizing agent rosiglitazone on circulating adipocytokine levels and brachial-ankle pulse wave velocity (baPWV) in non-diabetics. DESIGN AND METHODS: Ninety-nine subjects with prediabetes or non-diabetic MetS were randomly assigned to either rosiglitazone or an untreated control group (50 and 49 subjects respectively). The rosiglitazone group was treated daily for 12 weeks with 4 mg rosiglitazone. All subjects received a 75 g oral glucose test (OGTT) before and after treatment. In addition, baPWV, together with the levels of adiponectin, resistin, and high sensitivity C-reactive protein (hsCRP) were determined. RESULTS: Rosiglitazone treatment significantly increased circulating adiponectin levels (P < 0.001) relative to the control group (P = 0.21). Plasma resistin levels were unchanged in both the rosiglitazone-treated and -untreated groups, but baPWV and hsCRP were significantly decreased (P < 0.001 and P = 0.003 respectively) in the rosiglitazone group only. Multiple linear regression analysis showed that changes in plasma adiponectin and baPWV were significantly affected by rosiglitazone treatment. CONCLUSIONS: These data suggest that rosiglitazone may have an anti-atherogenic effect in subjects with prediabetes or non-diabetic MetS.

Vascular endothelial growth factor (VEGF) and soluble VEGF receptor FLT-1 in diabetic nephropathy.

BACKGROUND: Vascular endothelial growth factor (VEGF) and its receptors have been implicated in the pathogenesis of diabetic nephropathy. The objective of this study was to determine whether alterations of the plasma and urinary VEGF and sFLT-1 levels were related to the stages and risk factors of diabetic nephropathy. In addition, we also examined the regulation of the VEGF/sFLT-1 expression by various stimuli in cultured human proximal tubule cells (HPTC). METHODS: A total of 107 type 2 diabetic patients and 47 healthy control subjects were studied. The expression and protein levels of VEGF and sFLT-1 were measured by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). RESULTS: The urinary VEGF and sFLT-1 excretions were significantly increased in the microalbuminuric and proteinuric diabetic patients. The urinary VEGF levels were positively correlated with the urinary albumin to creatinine ratio (ACR), urinary sFLT-1 levels, and negatively correlated with creatinine clearance. The urinary sFLT-1 levels also showed a positive relationship with the urinary ACR. In cultured HPTC, high glucose stimuli rapidly up-regulated VEGF synthesis without having any effect on sFLT-1 synthesis. Interestingly, angiotensin II (Ang II) induced a dose-dependent increase in the synthesis of both VEGF and sFLT-1, which was significantly blocked by losartan. CONCLUSION: The urinary excretion of VEGF and sFLT-1 increased at a relatively early stage in diabetic nephropathy associated with urinary albumin excretion. A marked increase in both VEGF/sFLT-1 synthesis in response to Ang II was observed in HPTC, which was different from the response to glucose stimuli. These findings may imply that VEGF and sFLT-1 can actively take part in the pathogenesis of diabetic nephropathy.

Clinical study of adrenal incidentaloma in Korea.

BACKGROUND: This study was designed to evaluate the clinical, endocrinological and histological characteristics of adrenal incidentalomas. METHODS: Eighty patients (41, males; 38, females; age range 17-80 years) who were diagnosed with adrenal incidentaloma at Korea University Hospital from 1992 to 2003 were studied retrospectively. RESULTS: Endocrinological investigation revealed 16 pheochromocytomas (20%), nine Cushing's syndromes (11%), eight primary aldosteronism (10%) and 46 non-functioning tumors (58%). Forty-four patients received operations, and biopsies were performed on two patients. Pathologic examination revealed 16 adrenocortical adenomas (20%), five carcinomas (6%), 13 pheochromocytomas (16%), three metastatic cancers (4%), and other tumors (10%). The diameter of the carcinomas (mean: 10.8 cm, range: 5-19 cm) were significantly larger than the diameter of benign adenomas (mean: 2.84 cm, range: 1-6 cm) (p=0.002). According to the receiver operating charactenstic (ROC) curve analysis, the cut-off value of tumor size for discriminate malignant tumor was 4.75 cm (sensitivity 90%, specificity 58%). Twenty-four patients with non-functioning tumors were followed up for a period of 3 to 72 months. During the follow up period, two patients showed an increase in tumor size of more than 1 cm, and one patient developed Cushing's syndrome. Changes in mass size and function were observed only between 10 and 26 months after the initial diagnosis. CONCLUSIONS: These data show that an endocrine evaluation should be performed in all adrenal incidentalomas, and an adrenalectomy is recommended for tumors 5 cm or greater or tumors with adrenocortical hyperfunction. In addition, these tumors should be monitored for changes in mass size and function for a follow up period of approximately 26 months.