Alexander Kokkinos - Academia.edu (original) (raw)
Papers by Alexander Kokkinos
Journal of Molecular and Cellular Cardiology, 2008
Archives of Cardiovascular Diseases Supplements, 2010
Journal of Hypertension, 2015
ABSTRACT
Antioxidants in Health and Disease, 2015
Diabetologie und Stoffwechsel, 2006
Experimental Diabetes Research, 2011
Diabetologie und Stoffwechsel, 2009
Endocrine, 2007
Thyroid hormone plays a critical role in energy homeostasis through mechanisms, which are not ful... more Thyroid hormone plays a critical role in energy homeostasis through mechanisms, which are not fully understood. In the present study, we investigated possible alterations of important energy regulators such as leptin, adiponectin, and ghrelin in relation to changes in thyroid hormones. Thyroid hormone (250 microg/kg) was administered in male Wistar rats for 2 weeks (THYR), while hypothyroidism (HYPO) was induced by propylthiouracil administration (0.05% in drinking water) for 3 weeks. Untreated animals served as controls (NORM). Leptin and adiponectin were measured in plasma by ELISA, while total ghrelin was measured with RIA. Body weight was significantly reduced both in THYR and HYPO rats, while food intake was significantly increased in THYR and decreased in HYPO. This response was associated with various changes in leptin, adiponectin, and ghrelin in plasma. In fact, in THYR rats, leptin levels (mean +/- SEM) were 240 +/- 55 pg/ml as compared to 819 +/- 70 pg/ml in untreated rats (P < 0.05), while no changes were observed in ghrelin and adiponectin. In HYPO rats, leptin levels were 1400 +/- 200 pg/ml vs. 819 +/- 70 pg/ml in untreated rats (P < 0.05), while ghrelin and adiponectin were significantly increased in HYPO rats as compared to untreated rats (P < 0.05). Furthermore, T(3) and T(4) levels were inversely correlated to leptin (P = 0.014), while ghrelin and adiponectin were inversely correlated to weight changes (P = 0.05 and P = 0.03, respectively). In conclusion, leptin seems mainly to be involved in the thyroid hormone effects on energy homeostasis. Ghrelin and adiponectin may serve a compensatory physiological role in hypothyroidism.
European Journal of Nutrition, 2014
The aim of the present study was to examine the effects of consumption of desserts with low glyce... more The aim of the present study was to examine the effects of consumption of desserts with low glycemic index (GI) and low glycemic load (GL), as part of a balanced hypo-caloric diet, on anthropometric and biochemical parameters in patients with type 2 diabetes mellitus (T2DM). A total of 61 subjects with T2DM were randomly assigned to the intervention (n = 30) or to the control group (n = 31). Both groups followed the same hypo-caloric (-500 kcal) diet for 12 weeks. Consumption of four portions of low-GI/low-GL desserts/week was included in the diet in the intervention group while one portion of a favorite usual sweet/week was allowed to be consumed in the control group. Thirty subjects in the control and 28 subjects in the intervention group completed the trial. Body weight, body mass index, and waist circumference were reduced significantly in both groups. Arterial blood pressure, fasting blood glucose, glycosylated hemoglobin, insulin, and γ-GT were reduced significantly only in the intervention group; however, there were no significant differences between the two groups at endpoint. C-reactive protein was reduced in the intervention, and HDL cholesterol was also reduced in the control group; the reductions were significantly different at the end of the trial. No significant changes were observed in the other plasma lipids, uric acid, leptin, adiponectin, and interleukin-6 in either study group. Consumption of desserts with low GI/GL in a balanced hypo-caloric diet has a positive impact on anthropometric and metabolic parameters of patients with T2DM.
Rheumatology International, 2014
Giant cell arteritis (GCA) has been previously associated with cranial mononeuritis (usually opti... more Giant cell arteritis (GCA) has been previously associated with cranial mononeuritis (usually optic neuritis). We hereby describe a 68-year-old man who presented due to fever and diplopia of acute onset. Physical examination revealed left abducens nerve palsy and a hearing defect in the right ear. Brain imaging and cerebrospinal fluid analysis were not diagnostic. GCA was suspected, and treatment with high-dose methylprednisolone was initiated, leading to marked improvement. Temporal artery biopsy confirmed the presence of GCA. While considering corticosteroid tapering, the patient experienced hoarseness due to right laryngeal nerve palsy. Addition of cyclophosphamide to the treatment resulted in full response. GCA mainly affects large vessels, but one or more cranial nerve palsies may also occur. Following a review of the literature, this is the first report of three cranial nerve palsies in the setting of histologically proven GCA. The role of cyclophosphamide in this entity is also discussed.
International Journal of Peptides, 2010
Obesity Surgery, 2013
Morbidly obese patients display cardiac abnormalities which are partially reversed after weight l... more Morbidly obese patients display cardiac abnormalities which are partially reversed after weight loss. The aim of the present study was to assess the potential difference in cardiovascular disease indices between patients who underwent either gastric bypass surgery or sleeve gastrectomy. Thirty-seven morbidly obese patients who underwent either Roux-en-Y gastric bypass (RYGB) (n = 14) or SG (n = 23) were examined before, 3 and 6 months after surgery. Indices of cardiac autonomic nervous system activity were evaluated, namely baroreflex sensitivity (BRS) and heart rate variability (HRV). A complete echocardiographic study was performed in a subgroup of 17 patients (RYGB 8, SG 9) preoperatively and 6 months after surgery, evaluating epicardial fat thickness, aortic distensibility, left ventricular (LV) Tei index, left atrium diameter, ejection fraction, and LV mass. All subjects experienced significant (p < 0.001) and similar weight loss independently of the type of operation. BRS and HRV indices improved significantly and to the same degree after surgery in both groups. In the echocardiographic study, all parameters improved significantly at 6 months in comparison with the baseline values. In addition, the RYGB group displayed significantly greater reduction in epicardial fat thickness (p = 0.007) and also tended to have a better LV performance as expressed by the lower values of the Tei index (p = 0.06) compared to the SG group 6 months after surgery. Both RYGB and SG exert comparable effects on weight loss and improvement of cardiovascular parameters. RYGB displays a more beneficial influence on epicardial fat thickness and left ventricular performance than SG.
Nutrition, 2011
To examine differences in meal-induced thermogenesis and macronutrient oxidation between lean and... more To examine differences in meal-induced thermogenesis and macronutrient oxidation between lean and obese women after consumption of two different isocaloric meals, one rich in carbohydrate (CHO) and one rich in fat. A total of 19 lean and 22 obese women were studied on two occasions, 1 wk apart. In one visit they consumed a CHO-rich meal and in the other visit a fat-rich meal. The two meals were isocaloric and were given in random order. Resting energy expenditure and macronutrient oxidation rates were measured and calculated in the fasting state and every hour for 3 h after meal consumption. Meal-induced thermogenesis was not different between lean and obese subjects after the CHO-rich (P = 0.89) or fat-rich (P = 0.32) meal, but it was significantly higher after the CHO-rich compared with the fat-rich meal in the lean and the obese individuals (P < 0.05). Protein oxidation rate increased slightly but significantly after the test meals in both groups (P < 0.01). Fat oxidation rate decreased after consumption of the CHO-rich meal (P < 0.001), whereas it increased after consumption of the fat-rich meal in both groups (P < 0.01). CHO oxidation rate increased in both groups after consumption of the CHO-rich meal (P < 0.001). Oxidation rates of protein, fat, and CHO during the experiment were not significantly different between lean and obese participants. Meal-induced thermogenesis and macronutrient oxidation rates were not significantly different between lean and obese women after consumption of a CHO-rich or a fat-rich meal.
Molecular and Cellular Biochemistry, 2012
Journal of Diabetes and its Complications, 2006
Background and aimsThe interlead variation of QT duration in surface electrocardiogram [ECG; QT d... more Background and aimsThe interlead variation of QT duration in surface electrocardiogram [ECG; QT dispersion (QTd)] has been shown to predict mortality in both diabetic and general population. Diabetic cardiac autonomic neuropathy (CAN) is a common complication of diabetes, and it is also associated with worse prognosis among the diabetic population. In this study, we investigated the association between QTd duration and CAN, as well as other complications of diabetes in participants with Types 1 and 2 diabetes.
Journal of Diabetes and its Complications, 2011
Cardiac autonomic neuropathy (CAN) is a common diabetes complication associated with poor prognos... more Cardiac autonomic neuropathy (CAN) is a common diabetes complication associated with poor prognosis. This cross-sectional study aimed to examine for associations between CAN and metabolic and other parameters in patients with either type 1 (T1DM) or type 2 (T2DM) diabetes. A total of 600 patients (T1DM, n=200; T2DM, n=400) were recruited. Participants with overt nephropathy, macrovascular complications, and treated hypertension were excluded. CAN was diagnosed when two of the four classical autonomic function tests were abnormal. CAN was diagnosed in 42.0% and in 44.3% of the participants with T1DM and T2DM, respectively. Multivariate logistic regression analysis demonstrated that, in T1DM, the odds [OR (95% confidence intervals)] of CAN increased with higher waist circumference [1.36 (1.01-2.02)], systolic blood pressure [1.16 (1.03-1.31)], hypertension [1.19 (1.03-2.67)], smoking [1.10 (1.12-1.40], fasting glucose [1.01 (1.00-1.01)], HbA(1c) [1.69 (1.07-2.76)], pubertal diabetes onset [1.08 (1.03-1.24)], LDL cholesterol [1.01(1.00-1.02)], triglycerides [1.58 (1.24-1.48)], retinopathy [1.13 (1.04-1.41)], peripheral neuropathy [2.53 (1.07-2.99)], glomerular filtration rate [0.93 (0.87-0.99)], and microalbuminuria [1.24 (1.12-1.36)]. The same analysis in T2DM demonstrated that the odds of CAN increased with higher waist circumference [1.08 (1.00-1.39)], systolic blood pressure [1.06 (1.02-1.12)], hypertension [1.50 (1.24-2.03)], smoking [1.22 (1.14-1.49)], diabetes duration [1.20 (1.09-1.34)], fasting glucose [1.21 (1.12-1.31)], HbA(1c) [1.25 (1.08-1.45)], LDL cholesterol [1.35 (1.04-1.75)], triglycerides [1.30 (1.00-1.68)], retinopathy [1.24 (1.16-1.35)], peripheral neuropathy [1.79 (1.07-2.01)], glomerular filtration rate [0.96 (0.95-0.97)], and microalbuminuria [1.20 (1.14-1.36)]. CAN is common in diabetes and is associated with modifiable factors including central fat distribution, hypertension, dyslipidemia, worse diabetes control, and smoking, and with the other microvascular complications of diabetes. Our findings emphasize the need for a multifactorial intervention for the prevention of CAN.
Journal of Molecular and Cellular Cardiology, 2008
Archives of Cardiovascular Diseases Supplements, 2010
Journal of Hypertension, 2015
ABSTRACT
Antioxidants in Health and Disease, 2015
Diabetologie und Stoffwechsel, 2006
Experimental Diabetes Research, 2011
Diabetologie und Stoffwechsel, 2009
Endocrine, 2007
Thyroid hormone plays a critical role in energy homeostasis through mechanisms, which are not ful... more Thyroid hormone plays a critical role in energy homeostasis through mechanisms, which are not fully understood. In the present study, we investigated possible alterations of important energy regulators such as leptin, adiponectin, and ghrelin in relation to changes in thyroid hormones. Thyroid hormone (250 microg/kg) was administered in male Wistar rats for 2 weeks (THYR), while hypothyroidism (HYPO) was induced by propylthiouracil administration (0.05% in drinking water) for 3 weeks. Untreated animals served as controls (NORM). Leptin and adiponectin were measured in plasma by ELISA, while total ghrelin was measured with RIA. Body weight was significantly reduced both in THYR and HYPO rats, while food intake was significantly increased in THYR and decreased in HYPO. This response was associated with various changes in leptin, adiponectin, and ghrelin in plasma. In fact, in THYR rats, leptin levels (mean +/- SEM) were 240 +/- 55 pg/ml as compared to 819 +/- 70 pg/ml in untreated rats (P < 0.05), while no changes were observed in ghrelin and adiponectin. In HYPO rats, leptin levels were 1400 +/- 200 pg/ml vs. 819 +/- 70 pg/ml in untreated rats (P < 0.05), while ghrelin and adiponectin were significantly increased in HYPO rats as compared to untreated rats (P < 0.05). Furthermore, T(3) and T(4) levels were inversely correlated to leptin (P = 0.014), while ghrelin and adiponectin were inversely correlated to weight changes (P = 0.05 and P = 0.03, respectively). In conclusion, leptin seems mainly to be involved in the thyroid hormone effects on energy homeostasis. Ghrelin and adiponectin may serve a compensatory physiological role in hypothyroidism.
European Journal of Nutrition, 2014
The aim of the present study was to examine the effects of consumption of desserts with low glyce... more The aim of the present study was to examine the effects of consumption of desserts with low glycemic index (GI) and low glycemic load (GL), as part of a balanced hypo-caloric diet, on anthropometric and biochemical parameters in patients with type 2 diabetes mellitus (T2DM). A total of 61 subjects with T2DM were randomly assigned to the intervention (n = 30) or to the control group (n = 31). Both groups followed the same hypo-caloric (-500 kcal) diet for 12 weeks. Consumption of four portions of low-GI/low-GL desserts/week was included in the diet in the intervention group while one portion of a favorite usual sweet/week was allowed to be consumed in the control group. Thirty subjects in the control and 28 subjects in the intervention group completed the trial. Body weight, body mass index, and waist circumference were reduced significantly in both groups. Arterial blood pressure, fasting blood glucose, glycosylated hemoglobin, insulin, and γ-GT were reduced significantly only in the intervention group; however, there were no significant differences between the two groups at endpoint. C-reactive protein was reduced in the intervention, and HDL cholesterol was also reduced in the control group; the reductions were significantly different at the end of the trial. No significant changes were observed in the other plasma lipids, uric acid, leptin, adiponectin, and interleukin-6 in either study group. Consumption of desserts with low GI/GL in a balanced hypo-caloric diet has a positive impact on anthropometric and metabolic parameters of patients with T2DM.
Rheumatology International, 2014
Giant cell arteritis (GCA) has been previously associated with cranial mononeuritis (usually opti... more Giant cell arteritis (GCA) has been previously associated with cranial mononeuritis (usually optic neuritis). We hereby describe a 68-year-old man who presented due to fever and diplopia of acute onset. Physical examination revealed left abducens nerve palsy and a hearing defect in the right ear. Brain imaging and cerebrospinal fluid analysis were not diagnostic. GCA was suspected, and treatment with high-dose methylprednisolone was initiated, leading to marked improvement. Temporal artery biopsy confirmed the presence of GCA. While considering corticosteroid tapering, the patient experienced hoarseness due to right laryngeal nerve palsy. Addition of cyclophosphamide to the treatment resulted in full response. GCA mainly affects large vessels, but one or more cranial nerve palsies may also occur. Following a review of the literature, this is the first report of three cranial nerve palsies in the setting of histologically proven GCA. The role of cyclophosphamide in this entity is also discussed.
International Journal of Peptides, 2010
Obesity Surgery, 2013
Morbidly obese patients display cardiac abnormalities which are partially reversed after weight l... more Morbidly obese patients display cardiac abnormalities which are partially reversed after weight loss. The aim of the present study was to assess the potential difference in cardiovascular disease indices between patients who underwent either gastric bypass surgery or sleeve gastrectomy. Thirty-seven morbidly obese patients who underwent either Roux-en-Y gastric bypass (RYGB) (n = 14) or SG (n = 23) were examined before, 3 and 6 months after surgery. Indices of cardiac autonomic nervous system activity were evaluated, namely baroreflex sensitivity (BRS) and heart rate variability (HRV). A complete echocardiographic study was performed in a subgroup of 17 patients (RYGB 8, SG 9) preoperatively and 6 months after surgery, evaluating epicardial fat thickness, aortic distensibility, left ventricular (LV) Tei index, left atrium diameter, ejection fraction, and LV mass. All subjects experienced significant (p < 0.001) and similar weight loss independently of the type of operation. BRS and HRV indices improved significantly and to the same degree after surgery in both groups. In the echocardiographic study, all parameters improved significantly at 6 months in comparison with the baseline values. In addition, the RYGB group displayed significantly greater reduction in epicardial fat thickness (p = 0.007) and also tended to have a better LV performance as expressed by the lower values of the Tei index (p = 0.06) compared to the SG group 6 months after surgery. Both RYGB and SG exert comparable effects on weight loss and improvement of cardiovascular parameters. RYGB displays a more beneficial influence on epicardial fat thickness and left ventricular performance than SG.
Nutrition, 2011
To examine differences in meal-induced thermogenesis and macronutrient oxidation between lean and... more To examine differences in meal-induced thermogenesis and macronutrient oxidation between lean and obese women after consumption of two different isocaloric meals, one rich in carbohydrate (CHO) and one rich in fat. A total of 19 lean and 22 obese women were studied on two occasions, 1 wk apart. In one visit they consumed a CHO-rich meal and in the other visit a fat-rich meal. The two meals were isocaloric and were given in random order. Resting energy expenditure and macronutrient oxidation rates were measured and calculated in the fasting state and every hour for 3 h after meal consumption. Meal-induced thermogenesis was not different between lean and obese subjects after the CHO-rich (P = 0.89) or fat-rich (P = 0.32) meal, but it was significantly higher after the CHO-rich compared with the fat-rich meal in the lean and the obese individuals (P < 0.05). Protein oxidation rate increased slightly but significantly after the test meals in both groups (P < 0.01). Fat oxidation rate decreased after consumption of the CHO-rich meal (P < 0.001), whereas it increased after consumption of the fat-rich meal in both groups (P < 0.01). CHO oxidation rate increased in both groups after consumption of the CHO-rich meal (P < 0.001). Oxidation rates of protein, fat, and CHO during the experiment were not significantly different between lean and obese participants. Meal-induced thermogenesis and macronutrient oxidation rates were not significantly different between lean and obese women after consumption of a CHO-rich or a fat-rich meal.
Molecular and Cellular Biochemistry, 2012
Journal of Diabetes and its Complications, 2006
Background and aimsThe interlead variation of QT duration in surface electrocardiogram [ECG; QT d... more Background and aimsThe interlead variation of QT duration in surface electrocardiogram [ECG; QT dispersion (QTd)] has been shown to predict mortality in both diabetic and general population. Diabetic cardiac autonomic neuropathy (CAN) is a common complication of diabetes, and it is also associated with worse prognosis among the diabetic population. In this study, we investigated the association between QTd duration and CAN, as well as other complications of diabetes in participants with Types 1 and 2 diabetes.
Journal of Diabetes and its Complications, 2011
Cardiac autonomic neuropathy (CAN) is a common diabetes complication associated with poor prognos... more Cardiac autonomic neuropathy (CAN) is a common diabetes complication associated with poor prognosis. This cross-sectional study aimed to examine for associations between CAN and metabolic and other parameters in patients with either type 1 (T1DM) or type 2 (T2DM) diabetes. A total of 600 patients (T1DM, n=200; T2DM, n=400) were recruited. Participants with overt nephropathy, macrovascular complications, and treated hypertension were excluded. CAN was diagnosed when two of the four classical autonomic function tests were abnormal. CAN was diagnosed in 42.0% and in 44.3% of the participants with T1DM and T2DM, respectively. Multivariate logistic regression analysis demonstrated that, in T1DM, the odds [OR (95% confidence intervals)] of CAN increased with higher waist circumference [1.36 (1.01-2.02)], systolic blood pressure [1.16 (1.03-1.31)], hypertension [1.19 (1.03-2.67)], smoking [1.10 (1.12-1.40], fasting glucose [1.01 (1.00-1.01)], HbA(1c) [1.69 (1.07-2.76)], pubertal diabetes onset [1.08 (1.03-1.24)], LDL cholesterol [1.01(1.00-1.02)], triglycerides [1.58 (1.24-1.48)], retinopathy [1.13 (1.04-1.41)], peripheral neuropathy [2.53 (1.07-2.99)], glomerular filtration rate [0.93 (0.87-0.99)], and microalbuminuria [1.24 (1.12-1.36)]. The same analysis in T2DM demonstrated that the odds of CAN increased with higher waist circumference [1.08 (1.00-1.39)], systolic blood pressure [1.06 (1.02-1.12)], hypertension [1.50 (1.24-2.03)], smoking [1.22 (1.14-1.49)], diabetes duration [1.20 (1.09-1.34)], fasting glucose [1.21 (1.12-1.31)], HbA(1c) [1.25 (1.08-1.45)], LDL cholesterol [1.35 (1.04-1.75)], triglycerides [1.30 (1.00-1.68)], retinopathy [1.24 (1.16-1.35)], peripheral neuropathy [1.79 (1.07-2.01)], glomerular filtration rate [0.96 (0.95-0.97)], and microalbuminuria [1.20 (1.14-1.36)]. CAN is common in diabetes and is associated with modifiable factors including central fat distribution, hypertension, dyslipidemia, worse diabetes control, and smoking, and with the other microvascular complications of diabetes. Our findings emphasize the need for a multifactorial intervention for the prevention of CAN.