Athanasios Papatheodorou
Hellenic Air Force
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Featured researches published by Athanasios Papatheodorou.
Metabolism-clinical and Experimental | 2013
Stergios A. Polyzos; Jannis Kountouras; Athanasios Papatheodorou; Kalliopi Patsiaoura; Evangelia Katsiki; Efthimia Zafeiriadou; Christos Zavos; Kyriaki Anastasiadou; Evangelos Terpos
OBJECTIVE Clinical data regarding Helicobacter pylori (Hp) infection in nonalcoholic fatty liver disease (NAFLD) are limited. The aim was the evaluation of Hp infection in patients with NAFLD and its association with disease severity. METHODS 28 patients with biopsy-proven NAFLD (15 with simple nonalcoholic fatty liver [NAFL], 13 with nonalcoholic steatohepatitis [NASH]) and 25 matched healthy controls were recruited. Blood samples for anti-Hp Immunoglobulin G (IgG) and standard biochemical tests were obtained after overnight fasting, and (13)C urea breath test was performed before liver biopsy in NAFLD group. RESULTS Higher rates of anti-Hp IgG (P=.038) were observed in NAFLD compared to control group. Only two NAFLD patients neither were Hp IgG seropositive nor did they have a history of eradication treatment compared to 11 control subjects (P=.002). Both Hp infection (assessed by history of Hp eradication treatment and/or Hp IgG seropositivity) (P=.034) and log(HOMA-IR) (P=.007) could independently predict NAFLD in logistic regression analysis. There were similar rates of Hp IgG seropositivity or positivity in (13)C urea breath test or their combination between NAFL and NASH patients. There were no significant differences in steatosis grade, fibrosis stage, lobular or portal inflammation, or ballooning, when NAFLD patients were divided according to Hp IgG seropositivity or (13)C urea breath test positivity. CONCLUSIONS Hp infection may represent one more hit contributing to the pathogenesis of NAFL, though not to the progression from NAFL to NASH. These results warrant further validation. If confirmed, eradicating Hp infection may have certain therapeutic perspectives in NAFLD treatment.
Clinical Endocrinology | 2009
Athanasios D. Anastasilakis; Stergios A. Polyzos; Avraam Avramidis; Konstantinos A. Toulis; Athanasios Papatheodorou; Evangelos Terpos
Objective Parathyroid hormone increases the differentiation of osteoblast precursors through canonical wingless (Wnt) signalling, resulting in an osteoanabolic effect. We aimed to evaluate serum levels of the Wnt‐inhibitor Dickkopf‐1 (Dkk‐1) in postmenopausal women with established osteoporosis and their changes with teriparatide (TPTD – human recombinant PTH 1–34).
Haematologica | 2009
Ersi Voskaridou; Dimitrios Christoulas; Charoula Xirakia; Konstantinos Varvagiannis; Georgios Boutsikas; Antonios Bilalis; Efstathios Kastritis; Athanasios Papatheodorou; Evangelos Terpos
Dickkopf-1 is an inhibitor of Wnt signaling, which is crucial for osteoblast differentiation. This study shows that serum levels of Dicckopf-1 are increased in patients with thalassemia and osteoporosis. Interestingly, in a placebo-controlled, randomized therapeutic trial a 12-months treatment with zoledronic acid reduced serum Dickkopf-1 levels and increased bone mineral density in these patients. Dickkopf-1 is an inhibitor of Wnt signaling, which is crucial for osteoblast differentiation. We evaluated serum levels of Dickkopf-1 in 66 patients with thalassemia-induced osteoporosis who received therapy with zoledronic acid in a placebo-controlled, randomized trial. At baseline, thalassemia patients had increased serum levels of Dickkopf-1 that correlated with reduced bone mineral density of the lumbar spine and the distal radius. High Dickkopf-1 also correlated with increased bone resorption and reduced bone formation markers. Zoledronic acid produced a reduction in serum Dickkopf-1, which was associated with bone mineral density increase after 12 months of therapy. On the contrary, placebo group showed a borderline increase of Dickkopf-1, which was higher in patients who showed deterioration in pain scores. These results suggest that Dickkopf-1 is implicated in the pathogenesis of osteoporosis in thalassemia and reveal Dickkopf-1 as a possible target for the development of novel agents for the management of thalassemia-induced osteoporosis (ClinicalTrials. govIdentifier: NCT00346242).
American Journal of Hematology | 2014
Evangelos Terpos; Dimitrios Christoulas; Efstathios Kastritis; Eirini Katodritou; Athanasios Papatheodorou; Anastasia Pouli; Marie-Christine Kyrtsonis; Eurydiki Michalis; Xenophon Papanikolaou; Maria Gkotzamanidou; Efstathios Koulieris; Maria Gavriatopoulou; Konstantinos Zervas; Meletios A. Dimopoulos
The combination of lenalidomide plus dexamethasone (RD) is very effective for patients with relapsed/refractory myeloma. However, the effect of RD on bone metabolism has not been previously evaluated in these patients. To address this issue, we initially performed a retrospective study in 106 consecutive patients with relapsed or refractory myeloma who received RD. We measured the following bone indices on Cycle 1/Day 1 and then on Cycles 3 and 6/Day 28: dickkopf‐1 (Dkk‐1), sRANKL, osteoprotegerin (OPG), bone resorption markers (C‐telopeptide of collagen type‐I, CTX and TRACP‐5b) and bone formation markers (bone‐specific alkaline phosphatase‐bALP and osteocalcin). RD produced a reduction of CTX only in responders, with no effect on bone formation. To validate these results, we then evaluated prospectively 99 patients who received either RD (n = 50) or VRD (bortezomib + RD, n = 49). RD reduced CTX, mainly in responders but showed no effect on bone formation, confirming the result of the retrospective study. However, the addition of bortezomib to RD (VRD arm) reduced Dkk‐1, sRANKL/OPG, and CTX, while it increased bALP and OC after six cycles of therapy. These changes were irrespective of treatment response, which was similar between treatment arms. No skeletal‐related events were observed in the VRD arm while two, nonresponding patients treated with RD developed a vertebral fracture. We conclude that RD reduces bone resorption only in responding patients with relapsed/refractory myeloma but has no effect on bone formation. Combination with bortezomib, which enhances bone formation, seems to be preferred for the management of myeloma patients with osteolytic disease. Am. J. Hematol. 89:34–40, 2014.
International Journal of Cancer | 2012
Evangelos Terpos; Konstantinos Anargyrou; Eirini Katodritou; Efstathios Kastritis; Athanasios Papatheodorou; Dimitrios Christoulas; Anastasia Pouli; Eurydiki Michalis; Sosana Delimpasi; Maria Gkotzamanidou; Nikitas Nikitas; Vasilios Koumoustiotis; Dimitrios Margaritis; Konstantinos Tsionos; Ekaterini Stefanoudaki; John Meletis; Konstantinos Zervas; Meletios A. Dimopoulos
The circulating levels of several angiogenic cytokines [angiopoietin‐1 (Ang‐1), angiopoietin‐2 (Ang‐2), vascular endothelial growth factor (VEGF), angiogenin and basic fibroblast growth factor (bFGF)] were evaluated in 174 consecutive patients with newly diagnosed, symptomatic, multiple myeloma (MM). Circulating levels of Ang‐1/Ang‐2 were reduced in myeloma patients compared to controls, whereas VEGF and angiogenin levels were increased. Reduced angiopoietin‐1/angiopoietin‐2 ratio correlated with advanced disease features including international staging system (ISS)‐3 stage, renal impairment and extensive bone disease. Based on immunohistochemical results in 20 patients (10 with the higher and 10 with the lower values of circulating angiopoietin‐2) we found that angiopoietin‐2 is expressed by myeloma cells and correlates with increased microvessel density in subsets of patients. Furthermore, Ang‐1/Ang‐2 ratio correlated with survival. Patients with circulating Ang‐1/Ang‐2 below or equal to the median value (6.03) had a median survival of 26.3 months compared to 53 months of all others (p = 0.002). Interestingly, this was mainly observed in patients who received first‐line therapy with novel agent‐based regimens (65% of our patients). Furthermore, a subset of ISS‐3 patients with serum Ang‐1/Ang‐2 above the median value had favourable prognosis (median survival: 45 months versus 17 months of all others; p = 0.0001). The multivariate analysis revealed that low Ang‐1/Ang‐2 ratio could independently predict for inferior survival in our cohort of patients (relative risk (RR) 2.07, 95% CI 1.50–2.42; p < 0.001). These results highlight the role of angiopoietins pathway in the biology of MM and reveal novel targets for the development of antimyeloma agents.
Hormone and Metabolic Research | 2009
Stergios A. Polyzos; Athanasios D. Anastasilakis; Zoe Efstathiadou; Marina Kita; Ioannis Litsas; Avraam Avramidis; Georgios Arsos; Efstratios Moralidis; Spyridon Gerou; V. Pavlidou; Athanasios Papatheodorou; Evangelos Terpos
Overexpression of dickkopf (DKK)-1 in pagetic osteoblast cultures resulted in stimulation of osteoclast proliferation and inhibition of osteoblast growth. The aim of this study was to evaluate for the first time in Pagets disease of bone (PDB): 1) the serum levels of DKK1; 2) the association of DKK-1 with receptor activator of nuclear factor kappa B (RANKL) and osteoprotegerin (OPG); and 3) the effect of zoledronic acid (ZOL) on serum DKK-1, RANKL, and OPG. The study was conducted as a prospective open-label cohort study. Eleven patients with PDB (median age 60 years) were recruited. Twelve age- gender- and body mass index (BMI)-matched healthy individuals were used as controls at baseline. Blood samples were obtained before treatment (baseline) and after 3, 6, 12, and 18 months following ZOL infusion in patients with PDB. Patients with PDB had significantly higher RANKL (p=0.002), OPG (p=0.001), and bone markers (total alkaline phosphatase and C-terminal cross-linking telopeptide of type I collagen) compared with controls at baseline. There was no difference between groups in DKK-1 at baseline. Bone markers were both significantly decreased after therapy. Serum OPG, RANKL, RANKL:OPG ratio, and DKK-1 remained unaffected throughout the study. No correlations were found between OPG, RANKL, RANKL:OPG ratio, and DKK-1 at baseline nor between their changes during the study. Although both OPG and RANKL were increased in patients with PDB, ZOL had no effect on their serum levels. Serum DKK-1 was neither increased in patients with PDB nor related to OPG and RANKL, and was unaffected by ZOL.
Journal of Bone and Mineral Metabolism | 2010
Stergios A. Polyzos; Athanasios D. Anastasilakis; Ioannis Litsas; Zoe Efstathiadou; Marina Kita; Georgios Arsos; Efstratios Moralidis; Athanasios Papatheodorou; Evangelos Terpos
Juvenile Paget’s disease (JPD) is a rare, autosomal recessive osteopathy. Although it has phenotypic overlap with Paget’s disease of bone (PDB), it is probably a distinct entity. Because of its rarity, optimal disease management has not yet been established by randomized controlled trials. However, clinical, biochemical, and radiographic improvement has been reported after treatment with antiresorptive agents, including calcitonin and bisphosphonates (BPs). Compared with other BPs, zoledronic acid (ZOL) has a higher affinity to bone mineral and is a stronger inhibitor of the enzyme farnesyl pyrophosphate synthase (the main target of nitrogen-containing BPs), properties that explain the prolonged effect of ZOL on bone turnover and render it a therapeutic option for JPD, similar to PDB. We describe hereby, for the first time in the literature, the case of a patient with JPD who developed severe hypocalcemia and secondary hyperparathyroidism following effective treatment with ZOL.
Hormones (Greece) | 2014
Eva Kassi; Spiros Stavropoulos; Panayiotis Kokkoris; Antonis Galanos; Paraskevi Moutsatsou; Cleanthi Dimas; Athanasios Papatheodorou; Christos Zafeiris; George P. Lyritis
OBJECTIVEWe aimed to determine the prevalence of 25(OH)D (D2 and D3 independently) inadequacy in healthy young/middle-aged men and to investigate its relationship with BMD, bone markers, demographic and lifestyle parameters such as age, BMI, smoking, alcohol consumption and dietary calcium intake.DESIGNWe determined 25(OH)D levels using LC-MS/MS, a robust method for measurement of both 25(OH)D3 and 25(OH)D2, iPTH, osteocalcin, beta C terminal cross-linked telopeptides of type I collagen (b-CTXs), procollagen type 1 amino-terminal propeptide (PINP), BMD at L2-L4 and proximal femur, smoking habits, daily dietary calcium intake and alcohol consumption in 181 randomly selected healthy men aged 20–50y.RESULTSThe prevalence of vitamin D deficiency (25(OH)D <20ng/ml) was 50.3%. Only 8.8% of the participants had vitamin D sufficiency (25(OH)D ≥30ng/ml). We found a strong correlation between 25(OH)D and smoking in the totality of participants (p<0.001). 25(OH)D level was lower by approximately 4.3 ng/dl (p<0.001) in a smoker compared to a non-smoker among the totality of participants, while this value increased to 9.2ng/ml in the 40–50y subgroup (p=0.003). A multinomial logistic regression model demonstrated that a young smoker (20–29y) had 58% increased likelihood of having vitamin D deficiency compared to a non-smoker of the same age group (p=0.041).CONCLUSIONSA high prevalence of vitamin D deficiency was identified in a young and middle-aged male population. Smoking is a significant determinant of serum 25(OH)D, while it increases significantly the likelihood of having vitamin D deficiency. In our hands, vitamin D levels are not a determinant of bone turnover and BMD in this population.
Clinical Endocrinology | 2013
Polyzois Makras; Stergios A. Polyzos; Athanasios Papatheodorou; Panagiotis Kokkoris; Daniel Chatzifotiadis; Athanasios D. Anastasilakis
Denosumab is a new potent antiresorptive treatment of osteoporosis that can potentially induce a compensatory increase in parathyroid hormone (PTH) levels. We aimed to evaluate the alteration of PTH 1 and 6 months after denosumabs administration with different regimens of calcium and vitamin D (Ca/D) supplementation.
Hormone and Metabolic Research | 2013
Athanasios D. Anastasilakis; Stergios A. Polyzos; Polyzois Makras; M. Savvides; Grigorios T. Sakellariou; Athina Gkiomisi; Athanasios Papatheodorou; Evangelos Terpos
Periostin is a secreted extracellular matrix protein preferentially expressed in bone by osteocytes and periosteal osteoblasts. Reduced periostin expression may affect osteoblast differentiation and collagen type I synthesis and predispose to osteoporosis and increased fracture risk. We aimed to evaluate circulating periostin levels in postmenopausal women with low bone mass, their possible correlations with clinical and laboratory parameters, as well as the 3-month effect of zoledronic acid. Serum samples for periostin, 25-hydroxyvitamin D, parathyroid hormone (PTH), C-terminal telopeptide of type I collagen (CTx), and total alkaline phosphatase (tALP) were obtained from 46 postmenopausal women with low bone mass at baseline and 3 months after zoledronic acid infusion and from 30 age-matched, postmenopausal controls with normal bone mass at baseline. There was no difference in periostin levels between women with normal and low bone mass (250±15 vs. 272±14 ng/ml, respectively; p=0.279). Periostin remained essentially unchanged after zoledronic acid infusion (262±18 ng/ml; p=0.130). Serum periostin levels at baseline were not affected by previous bisphosphonate treatment, and were correlated only to tALP (rs=0.351; p=0.018). In multiple linear regression analysis, tALP (B=3.17; 95% CI=0.59-5.79; p=0.018) was associated with serum periostin levels at baseline, independently from previous anti-osteoporotic treatment, age, body mass index, and 25-hydroxyvitamin D. In conclusion, serum periostin levels do not differ between postmenopausal women with normal and low bone mass and are not affected by zoledronic acid treatment. Women with higher tALP have independently higher periostin levels.