Calcium-phosphorus relationships in the combined course of stable ischemic heart disease in patients with obesity

The purpose of the study was to optimize the diagnosis and prediction of the development of structural and functional disorders of bone tissue in patients with SCHD and obesity. Thus, lipid profile analysis showed a clinically significant increase in total cholesterol and triglycerides in patients with SCHD. Serum bone mineral status did not exceed normal values, but serum total calcium levels were significantly higher in patients with SCHD and obesity compared to other groups. The indicators of calcium-phosphorus metabolism in the daily urine of patients with SCHD were significantly higher. When conducting densitometric studies in patients with SCHD with normal weight, osteopenic conditions were diagnosed more often than in patients with overweight and obesity. That is, the comorbid course of SCHD and obesity is a high risk of osteodeficiency, which is confirmed by early changes in calcium-phosphorus metabolism.

Effects of competitive physical activity on serum irisin levels and bone turnover markers

Background Irisin, a myokine, is a polypeptide derived from the cleavage of the extracellular domain of fibronectin domain-containing protein 5, a receptor that is present on different tissues (skeletal muscle, pericardium, myocardium, and brain), whose functions are not yet fully defined. Purpose The main aim of our study was to evaluate the effect of competitive physical activity on serum irisin levels and bone turnover markers. Methods Fifteen male footballers and an equal number of subjects of the same age and gender, but with a predominantly sedentary lifestyle, had their serum levels of irisin and bone turnover markers measured. Bone mineral status was evaluated in both groups by quantitative bone ultrasound of the calcaneus. In addition, only in footballers, biochemical analyses were repeated after 3 months. Results We did not observe significant differences in the serum levels of calcium, phosphorus, and parathyroid hormone between the two groups. The footballers had significantly higher quantitative bone ultrasound, 25-OH vitamin D, and creatinine values than the controls. There were also no significant differences in the bone alkaline phosphatase, carboxy-terminal telopeptide of type I collagen, osteoprotegerin, sclerostin or Dkk-1 values, while the irisin levels (+ 89%, p < 0.001) and RANKL were significantly higher in the footballers compared to those in the controls. Conclusion Our study shows that footballers have significantly higher serum irisin values than the general population. Irisin could be the "trait d’union" between bone health and physical activity.

Pseudohypoparathyroidism: application of the Italian common healthcare-pathway for a homogeneous clinical approach and a shared follow up

Background Pseudohypoparathyroidism (PHP) represents a heterogeneous group of rare endocrine disorders caused by (epi) genetic abnormalities affecting the GNAS locus. It is mainly characterized by resistance to PTH and TSH, and by peculiar clinical features such as short stature, obesity, cognitive impairment, subcutaneous ossifications and brachydactyly. Delayed puberty, GHRH and calcitonin resistances have also been described. The healthcare-pathway recently proposed by the Italian Society of Pediatric Endocrinology and Diabetology (ISPED) has provided a standardized clinical approach to these conditions. The purpose of the present study was to evaluate its application in clinical practice, and to collect data for setting future specific studies. Methods Through a semi-structured survey, based on the indications of the care-pathway, data on PHP clinical management were collected. The compilation of each data in the survey was read as an index of the adoption of the healthcare-pathway in clinical practice. Results In addition to the proposing Center, 4 Centers joined the study, thus obtaining a large collection of data on 48 PHP patients. Highest rates in the completion of data were obtained for diagnostic history, auxological measurements and subcutaneous ossifications evaluation. As expected, the availability of data for the other investigated fields was lower, coming from recent research studies. More information has been obtained on hormonal resistance classically involved in PHP (PTH, TSH, GHRH and GnRH) and on cognitive impairment, while a few data has been collected on bone mineral status, calcitonin levels and glucolipid metabolism. Conclusions The presented data show that the ISPED healthcare-pathway could represent a valid tool both to confirm the clinical approach to PHP patients and to allow homogeneous data collection; however, it has not yet been fully adopted. The strengthening of the network among the major Italian Endocrine Centers will contribute to improve its application in clinical practice, optimizing the follow-up of these patients and increasing knowledge on PHP.

The effect of Irisin on bone cells in vivo and in vitro

The myokine Irisin, produced during physical exercise, has an anabolic effect on bone, both in vitro and in vivo. Very recently, using a controlled in vitro 3D cell model to mimic the bone microenvironment aboard the International Space Station, it has been shown that Irisin treatment in microgravity prevents the down-regulation of the transcription factors Atf4, Runx2 and Osterix, as well as Collagen I and Osteoprotegerin proteins, crucial for osteoblast differentiation in physiologic conditions. Irisin action has also been investigated in human subjects, in which it correlates with bone health status, supporting its physiological importance also in human bone, both in healthy subjects and in patients suffering from diseases related to bone metabolism, such as hyperparathyroidism and type 1 diabetes. Low levels of circulating Irisin have been found in post-menopausal women affected by hyperparathyroidism. Furthermore, Irisin is positively correlated with bone strength in athletes and bone mineral density in football players. Moreover, in healthy children, Irisin is positively associated with bone mineral status and in children with type 1 diabetes, Irisin is positively correlated with improved glycemic control and skeletal health. In this review, we will focus on recent findings about Irisin action on microgravity induced bone loss and on osteocyte activity and survival through its αV/β5 integrin receptor.

Bone Mineral Status in Sub-clinical Hypothyroidism: A Case-control Study

Introduction: Hypothyroidism is the most common thyroid disorder which results in various metabolic disturbances. The disturbance in the bone minerals, calcium and phosphorus contribute to the most common imbalance. This is commonly overlooked in sub-clinical hypothyroidism, based on the absence of symptoms in patients related to thyroid hormone imbalance. The diagnosis of sub-clinical hypothyroidism is generally incidental and is based on the Thyroid Stimulating Hormone (TSH) level. The concentration of the circulating thyroid hormones, T3 (Triiodothyronine) and T4 (Thyroxine) are not altered in this condition. Aim: To study the Ca/P ratio, an early indicator of osteoporotic marker among the patients with hypothyroidism. Materials and Methods: The present study was designed as a case-control study and involved 35 controls with normal thyroid function and 35 subjects with sub-clinical hypothyroidism, of age group 20-45 years. The serum samples were analysed for calcium and phosphorus by their respective methods. The samples were analysed on the same day to maintain the stability of the parameters. Calcium/Phosphorus ratio (Ca/P) was calculated. Results: Serum Calcium was found to be less (8.33±0.30) and serum phosphorus was more (6.61±0.88) in sub-clinical hypothyroidism when compared to control group. Therefore, a reversal of Ca/P ratio was (1.26±0.34) was noted. Conclusion: This study underlines the necessity for patients with sub-clinical hypothyroidism to be monitored for bone mineral status to avoid complications in bone health.

Risk Factors of Bone Loss in Spondyloarthritis

We aimed to determine the bone mineral status in patients with spondyloarthritis (SA), and to assess the impact of parameters associated with bone loss on bone mineral density (BMD). Seventy-five patients (62 men) with SA fulfilling the modified New York criteria were included in a cross-sectional study during one year. BMD was assessed in all patients using dual-energy X-ray absorptiometry. The patient’s average age was 36.8 years. Sixty-five patients (86.6%) had bone loss. The lumbar spine was the site most affected by osteoporosis (37%). Bone loss was significantly associated with low BMI, peripheral joint involvement, active disease (high ASDASESR and BASDAI), vitamin D insufficiency, elevated erythrocyte sedimentation rate (ESR) and c-reactive protein, as well as high BASRI, high BASMI, and with the use of csDMARDs or anti-TNF alpha therapy. The disease activity, biologic inflammation, low vitamin D level, peripheral joint involvement, and structural damage were the major factors that induce bone loss in SA patients. Multivariate analysis showed that only high ESR level (AOR 19.9, 95% CI) and peripheral arthritis (AOR 14.5, 95% IC) were independent risk factors of bone loss. Our study shows that bone loss was a multifactorial complication of SA.

Sclerostin and osteoprotegerin: new markers of chronic kidney disease mediated mineral and bone disease in children

BackgroundSclerostin and osteoprotegerin (OPG) are new markers of chronic kidney disease (CKD) mediated mineral bone disease (CKD-MBD) which were extensively evaluated in adult population. We aimed to evaluate the associations between serum levels of sclerostin/OPG and parameters of bone turnover and compare the serum levels of sclerostin/OPG in different stages of CKD in children.Methods70 children with CKD stage 1-5, aged 2-21 years were examined. Serum levels of alkaline phosphatase (ALP), creatinine, total calcium, phosphorus , intact parathyroid hormone (iPTH) and vitamin D were measured. Serum sclerostin and OPG levels were measured in children with different levels of CKD stage and their association with bone turnover parameters were noted.ResultsWe did not observe any significant correlation between serum levels of sclerostin and OPG and stages of CKD. A negative relationship was present between serum sclerostin and 25-OH vitamin D levels. Osteoprotegerin was positively and significantly correlated with ALP but serum sclerostin was negatively correlated with ALP.ConclusionOur study, which includes only children and adolescents with a growing skeleton under uremic conditions and excluding diabetes and atherosclerosis interference, is very valuable. We couldn't find any significant relationship between either sclerostin or OPG levels among different stages of CKD. Also our study demonstared a strong negative relationship between ALP and sclerostin levels and a strong positive relationship between ALP and OPG levels, reminding the importance of ALP levels to predict the bone-mineral status of the children with CKD.

Modulation of the Paracrine Kynurenic System in Bone as a New Regulator of Osteoblastogenesis and Bone Mineral Status in an Animal Model of Chronic Kidney Disease Treated with LP533401

An increase in the peripheral synthesis of serotonin and kynurenine, observed during the chronic kidney disease (CKD) course, is negatively associated with bone health. Serotonin and kynurenine are connected by the common precursor, tryptophan. LP533401 is an inhibitor of peripheral serotonin synthesis. This study aimed to establish if the inhibition of serotonin synthesis by LP533401 may affect the kynurenine pathway activity in bone tissue and its potential consequence with regard to osteogenesis and bone mineral status. Nephrectomized rats were treated with LP533401 at a dose of 30 and 100 mg/kg daily for eight weeks. Tryptophan and kynurenine concentrations were determined, and tryptophan 2,3-dioxygenase (TDO) expression was assessed. We discovered the presence of a TDO-dependent, paracrine kynurenic system in the bone of rats with CKD. Its modulation during LP533401 treatment was associated with impaired bone mineral status. Changes in TDO expression affecting the kynurenine pathway activity were related to the imbalance between peripheral serotonin and 25-hydroxyvitamin D. There were also close associations between the expression of genes participating in osteoblastogenesis and activation of the kynurenine pathway in the bones of LP53301-treated rats. Our results represent the next step in studying the role of tryptophan metabolites in renal osteodystrophy.

P1477EFFECT OF INTRADIALYTIC EXERCISE IN A MEXICAN MAINTENANCE HEMODIALYSIS POPULATION

Background and Aims The use of intradialytic exercise has been associated with improved clearance, oxygen consumption, quality of life, and physical performance. The aim of this study was to describe the association between of intradialytic exercise and some outcomes in a Mexican maintenance hemodialysis (HD) population. Method Observational comparative study that included 84 maintenance HD patients from one HD center in Mexico City. The population was grouped according to the intradialytic exercise local record. The aerobic intradialytic exercise protocol includes cycling for 30-45 min during the first 2 hours of the HD according to each patient’s ability. A retrospective registry of clinical and biochemical parameters was realized. Also, the hemodynamic parameters of the last six HD sessions for each patient was included. Data analysis was carried out through descriptive and inferential statistics. Results Of the total population, 45.2% were men (n= 38) and the mean age was 53.6 + 17 years. Fifty one percent (n= 43) had diabetes mellitus (DM), which resulted more prevalent in the subgroup of patients without intradialytic exercise (p=0.03) No differences between groups were present in age, history of previous peritoneal dialysis or kidney transplant. The rest of baseline data are shown in Table 1. The subgroup of patients who underwent intradialytic exercise presented higher levels of serum albumin (p=0.03) and lower levels of parathormone (p=0.03). A total of 504 HD sessions were analysed and intradialytic exercise was performed in 64.3% (n=324). Patients in the intradialytic exercise program presented high levels of systolic and diastolic blood pressure (graphic 1). Intradialytic hypotension occurred in 5.2% (n=26) and no differences are shown between groups (p=0.78). No mayor side effects were reported. Conclusion The intradialytic exercise could improve nutritional and bone-mineral status markers. The patients in an intradialytic exercise program presented higher levels of blood pressure.