Subcutaneous and total fat at L4-L5 and subcutaneous, visceral and total fat at L3-L4 are important contributors of fasting and postprandial adiponectin levels.

OBJECTIVES: Insulin resistance and central obesity have been implicated in the pathogenesis of hypoadiponectinemia in obesity. The aim of this study is to evaluate circulating post-prandial adiponectin in relation to glucose and insulin metabolism, indexes of insulin resistance and sensitivity and, indexes of body fat accumulation and distribution in obese men. METHODS: Twenty-eight non-diabetic men underwent an OGTT followed by an oral fat load and were studied at baseline and for 5 h post-prandially for serum adiponectin, glucose and insulin. Insulin resistance was estimated by Homeostasis model assessment (HOMA) and insulin sensitivity by Matsuda index. Body fat accumulation and distribution were evaluated by anthropometric indexes and multiple slices MRI of the abdomen and hip. RESULTS: Adiponectin was negatively correlated to insulin levels. Fasting and area under the curve (AUC) adiponectin levels were negatively correlated to HOMA (both p < 0.01) and positively to Matsuda index (both p < 0.05). Negative correlations between fasting adiponectin and total fat (r = -0.408, p < 0.05), AUC adiponectin and subcutaneous, visceral and total fat (r = -0.375, -0.413 and -0.475 respectively, all p < 0.05) at L3-L4 were found, and negative correlations between fasting adiponectin and subcutaneous (r = -0.402, p < 0.05) and total fat (r = -0.491, p < 0.05) and between AUC adiponectin and subcutaneous and total fat (r = -0.506 and -0.547, respectively, both p < 0.01) were present at L4-L5. CONCLUSIONS: Circulating adiponectin is inversely correlated to both visceral and subcutaneous fat in non-diabetic men, implying that both compartments are important for adiponectin levels. The best correlation is found at measurement site L4-L5.

High-intensity exercise and carbohydrate-reduced energy-restricted diet in obese individuals.

Continuous high glycemic load and inactivity challenge glucose homeostasis and fat oxidation. Hyperglycemia and high intramuscular glucose levels mediate insulin resistance, a precursor state of type 2 diabetes. The aim was to investigate whether a carbohydrate (CHO)-reduced diet combined with high-intensity interval training (HIIT) enhances the beneficial effects of the diet alone on insulin sensitivity and fat oxidation in obese individuals. Nineteen obese subjects underwent 14 days of CHO-reduced and energy-restricted diet. Ten of them combined the diet with HIIT (4 min bouts at 90% VO(2peak) up to 10 times, 3 times a week). Oral glucose insulin sensitivity (OGIS) increased significantly in both groups; [diet-exercise (DE) group: pre 377 ± 70, post 396 ± 68 mL min(-1) m(-2); diet (D) group: pre 365 ± 91, post 404 ± 87 mL min(-1) m(-2); P < 0.001]. Fasting respiratory exchange ratio (RER) decreased significantly in both groups (DE group: pre 0.91 ± 0.06, post 0.88 ± 0.06; D group: pre 0.92 ± 0.07, post 0.86 ± 0.07; P = 0.002). VO(2peak) increased significantly in the DE group (pre 27 ± 5, post 32 ± 6 mL kg(-1) min(-1); P < 0.001), but not in the D group (pre 26 ± 9, post 26 ± 8 mL kg(-1) min(-1)). Lean mass and resistin were preserved only in the DE group (P < 0.05). Fourteen days of CHO-reduced diet improved OGIS and fat oxidation (RER) in obese subjects. The energy-balanced HIIT did not further enhance these parameters, but increased aerobic capacity (VO(2peak)) and preserved lean mass and resistin.

Serum pattern of circulating adipokines throughout the physiological menstrual cycle.

This study investigated the serum levels of resistin, adiponectin and leptin during the physiological menstrual cycle. Sixteen women (age: 19-30 years; body mass index: 19.46-24.9) with regular menstrual cycles participated. Fasting blood samples were collected on alternate days throughout a full menstrual cycle. Mean resistin concentrations were slightly higher during the luteal phase (5.30+/-0.23 ng/ml) compared to the follicular (4.68+/-0.07 ng/ml) and midcycle (4.86+/-0.09 ng/ml) phases (p=0.032). Mean leptin concentrations during the follicular phase (18.14+/-0.28 ng/ml) were significantly lower compared to the midcycle (21.79+/-0.29 ng/ml, p=0.006) and luteal phases (23.75+/-0.64 ng/ml, p<0.001). The variation of adiponectin concentrations throughout the menstrual cycle was not significant. According to the results, circulating resistin, likewise leptin concentrations vary significantly during the physiological menstrual cycle presenting with higher values during the luteal phase. This pattern, although its physiological importance is not clear, suggests that resistin, likewise to leptin, may have a role in the regulation of cyclic female reproductive functions. The stable adiponectin concentrations throughout the menstrual cycle indicate that this adipokine probably does not play a considerable role in female reproductive functions.

Ghrelin in pathological conditions.

The recently identified gastric hormone ghrelin was initially described as a natural Growth Hormone Secretagogue Receptor ligand. Apart from ghrelin's first discovered action, which was the stimulation of Growth Hormone release, implications for many other functions have been reported. It seems that ghrelin exhibits an important role in conditions related to processes regulating nutrition, body composition and growth, as well as heart, liver, thyroid or kidney dysfunction. In this review, current available knowledge about ghrelin's role in various pathological conditions is presented.

Screening chest radiography: results from a Greek cross-sectional survey.

BACKGROUND: Public health authorities worldwide discourage the use of chest radiography as a screening modality, as the diagnostic performance of chest radiography does not justify its application for screening and may even be harmful, since people with false positive results may experience anxiety and concern. Despite the accumulated evidence, various reports suggest that primary care physicians throughout the world still prescribe chest radiography for screening. We therefore set out to index the use of chest radiography for screening purposes among the healthy adult population and to analyze its relationship with possible trigger factors. METHODS: The study was designed as a cross-sectional survey. Five thousand four hundred and ninety-nine healthy adults, coming from 26 Greek provinces were surveyed for screening practice habits in the nationwide anticancer study. Data were obtained for the use of screening chest radiography. Impact of age, gender, tobacco exposure, family history positive for malignancies and professional-risk for lung diseases was further analyzed. RESULTS: we found that 20% (n = 1099) of the surveyed individuals underwent chest radiography for screening purposes for at least one time during the previous three years. Among those, 24% do so with a frequency equal or higher than once yearly, and 48% with a frequency equal or higher than every three years. Screening for chest radiography was more commonly adopted among males (OR 1.130, 95% CI 0.988-1.292), pensioners (OR 1.319, CI 1.093-1.593) and individuals with a positive family history for lung cancer (OR 1.251, CI 0.988-1.583). Multivariate analysis confirmed these results. CONCLUSION: Despite formal recommendations, chest radiography for screening purposes was a common practice among the analyzed sample of Greek adults. This practice is of questionable value since the positive predictive value of chest radiography is low. The implementation of even a relatively inexpensive imaging study on a national scale would greatly burden health economics and the workload of radiology departments.

Colorectal cancer screening coverage in Greece. PACMeR 02.01 study collaboration.

BACKGROUND AND AIMS: Colorectal cancer is a major cause of cancer death in European countries and differences in screening implementation may in part explain USA vs European survival differences. Despite the evidence, no study has evaluated the population colorectal cancer screening (CCS) coverage in any European country. We aimed to index the current CCS practices among a large sample of Greek healthy adults. MATERIALS AND METHODS: The study was designed as a cross-sectional survey. Screening practice habits of 5,259 healthy adults, aged 50-80, were surveyed. Both overall and screening practices of stool occult blood test (SOBT), digital rectal examination (DRE), and colonoscopy or sigmoidoscopy (COL/SIG) were analyzed. RESULTS: Of the population analyzed, 90.1% declared that they were interested in cancer prevention activities. Overall SOBT practice rate within the last 2 years was 4.77%. When only screening procedures were analyzed, this percentage shrank to 1.73%. Overall and screening COL/SIG rates within the last 10 years were 8.76 and 1.74%, respectively. The respective proportions of individuals who underwent DRE were 14.54 and 5.2%. Evidence-based screening practices were influenced by age, family history of colorectal cancer, profession, and educational level; however, SOBT and colonoscopy/sigmoidoscopy did not overcome 4.1 and 4.6% in any subpopulation analyzed. CONCLUSION: The level of CCS coverage among the examined sample of Greek adults was discouraging. Surveys among other European countries are encouraged.

Colorectal cancer screening awareness in European primary care.

BACKGROUND: Adjustment for stage at diagnosis markedly reduces USA versus European colorectal cancer survival differences and a screening bias was therefore suspected. Moreover, little is known about colorectal cancer screening habits in European primary care and the history of guidelines implementation. The purpose of the study was to index the overall colorectal cancer screening attitudes of European physicians involved in primary care activities. METHODS: A systematic literature-search was performed in three major medical libraries: PubMed/MEDLINE, ISI web of science, and COCHRANE. RESULTS: We found only five eligible studies, but valuable data were presented only in four. Colorectal cancer screening was recommended by 65-95% of physicians, but the major part of them implemented it only among high-risk individuals; stool occult blood testing was advised by 42-83% and prescription of screening endoscopic modalities was inconsistent. Most European reports found were not eligible and were mainly focused on diagnostic delay in symptomatic subjects rather than on screening procedures among asymptomatic individuals. CONCLUSION: In comparison with European practice, colorectal cancer screening habits of American physicians are to a greater extent rational, evidence-based and well monitored and have a longer tradition in medical care thus allowing better prevention services for asymptomatic individuals.