Calcium regulation and bone mineral metabolism in elderly patients with chronic kidney disease

Association of urinary calcium excretion with chronic kidney disease in patients with type 2 diabetes

PURPOSE

Herein, we investigated the correlation between urinary calcium excretion (UCaE) and chronic kidney disease (CKD) in patients with type 2 diabetes mellitus (T2DM).

METHODS

From August 2018 to January 2023, a total of 2031 T2DM patients providing 24-h urine samples were included in the final analyses. Patients were separated into four cohorts, based on the UCaE quartiles. We then analyzed renal functional indicators like estimated glomerular filtration rate (eGFR) and urinary albumin excretion (UAE) among the four groups. Lastly, we utilized multivariable logistic regression models to investigate the correlation between UCaE and CKD.

RESULTS

After adjusting for confounding factors, we observed a decreasing trend in CKD prevalence (36.3%, 13.0%, 7.5%, and 6.6%, respectively, P < 0.001) across the UCaE quartiles. Albuminuria (55.5% vs. 40.0%, 36.5%, 37.4%) and macroalbuminuria prevalence (20.0% vs. 9.3%, 5.2%, 5.7%) in the lowest quartile were markedly elevated, compared to the remaining three quartiles (P < 0.001). Meanwhile, the eGFR level (P < 0.001) showed a clearly increasing trend across the UCaE quartiles, and patients with moderate-to-severe decreases in eGFR levels (with cutoff limits at 30-59, 15-30, and < 15 mL/min/1.73m2) were mostly found in the lowest quartile (P < 0.001). Logistic regression analysis revealed that patients in the lowest quartile experienced an enhanced prevalence of CKD, relative to those in the highest quartile (odds ratio: 5.90, 95% confidence interval: 3.60-9.67, P < 0.001).

CONCLUSION

Decreased UCaE was independently associated with the CKD prevalence in T2DM patients.

Nutritional Status and Serum Levels of Micronutrients in an Elderly Group Who Participate in the Program for Complementary Food in Older People (PACAM) from the Metropolitan Region, Santiago de Chile

The increase in the Chilean elderly population has promoted public policies to favor an adequate nutrition in later life. This study evaluated the nutritional status, micronutrients intake and serum micronutrients levels of an elderly group beneficiary of the PACAM from the Metropolitan Region, Santiago de Chile. Anthropometric and dietary survey (24 h food recalls) were assessed in 182 elderly individuals (60 and 80 years old). Blood serum collection was used to measure the micronutrient status. The sample was comprised by 12.6%, 46.1%, 28.0% and 13.2% of underweight, normal weight, overweight and obese subjects, respectively. Women presented 11% of underweight, 45% of normal weight and 44% of overweight and obese, while men—18%, 50% and 32%, respectively. Only the 63% of the elderlies consumed PACAM foods, reaching average daily intakes below (50%) the recommended daily serving. Serum deficiencies of 25-hydroxyvitamin D (88%), vitamin B₁₂ (33%) and calcium (36%) were observed, being the highest ones in the PACAM foods women (60–75 years old). Chilean elderlies presented mainly a normal weight; however, an important proportion of overweight/obese subjects was observed. Although PACAM foods consumption significantly increased the micronutrient intake, it was not enough to ensure an adequate serum micronutrient levels in the elderly.

Association between metabolic parameters and risks of anemia and electrolyte disturbances among stages 3-5 chronic kidney disease patients in Taiwan

Background

Anemia and electrolyte disturbances are adverse outcomes of chronic kidney disease (CKD). This study explored the association between metabolic parameters with anemia and electrolyte and mineral disorders among CKD patients in Taiwan.

Methods

This cross-sectional study with a total of 2176 CKD stages 3–5 patients were collected from the Department of Nephrology at Shuang Ho Hospital, Taipei Medical University through the “Chronic Kidney Disease Common Care Network” database from December 2008 to April 2019. A multivariable-adjusted logistic regression expressed as odd ratios (OR) was performed to assess the association of metabolic parameters with anemia and electrolyte and mineral disorders.

Results

Elevated diastolic blood pressure, fasting blood glucose, and glycated hemoglobin A1c (HbA1c) were associated with presence of anemia. Similarly, elevated fasting blood glucose and HbA1c were associated with hyponatremia (OR = 1.59 and 1.58, P for both < 0.01) and hypercalcemia (OR = 1.38 and 1.33, P for both < 0.05). There was no significant association in serum lipid levels with presence of anemia. However, total triglycerides, total cholesterol and low-density lipoprotein-cholesterol were only associated with presence of hypercalcemia (OR = 1.43, 1.95 and 3.08, respectively, P for all < 0.05).

Conclusions

Elevated diastolic blood pressure, fasting blood glucose, HbA1c and blood lipids are associated with anemia or electrolyte and mineral disorders in CKD patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02590-w.

Safety and efficacy of etelcalcetide, an intravenous calcimimetic, for up to 52 weeks in hemodialysis patients with secondary hyperparathyroidism: results of a post-marketing surveillance in Japan

Background

Etelcalcetide is a second-generation calcimimetic for the management of secondary hyperparathyroidism (SHPT) in patients on dialysis. We performed a post-marketing surveillance (PMS) to obtain information on the safety and efficacy of etelcalcetide in clinical practice in Japan.

Methods

This PMS enrolled SHPT patients who started initial treatment with etelcalcetide between April 1, 2017 and February 28, 2018 in Japan. Safety [adverse drug reactions (ADRs)] and efficacy [serum intact parathyroid hormone (iPTH), corrected calcium (cCa), phosphorous (P), and alkaline phosphatase (ALP)] were recorded for up to 52 weeks or until treatment discontinuation. Treatment decisions were at the physician’s discretion.

Results

Of 1226 patients enrolled across 282 centers, safety and efficacy data were available for 1195 and 1192, respectively, while 933 continued treatment to Week 52. The starting dose was 5 mg in 82.0% of patients. There were 218 ADRs in 169 patients (14.1%). Metabolism and nutrition disorders (8.8%), adverse laboratory test results (1.8%), and gastrointestinal disorders (1.6%) were the most frequent classes of ADRs. Hypocalcemia-related ADRs occurred in 104 patients (8.7%). The percentage of patients with iPTH levels within the target range (60–240 pg/mL) steadily increased from 19.5% at Week 0 to 64.1% at Week 52 or last dose. cCa, P, and ALP levels remained well controlled.

Conclusion

This was the first real-world, large-scale, long-term observational PMS of etelcalcetide in Japan. We did not observe any new safety concerns. Etelcalcetide was associated with clinically relevant improvements in serum iPTH and maintenance of serum cCa, P, and ALP levels.

Electronic supplementary material

The online version of this article (10.1007/s10157-020-01936-2) contains supplementary material, which is available to authorized users.

Calcimimetic compound NPS R-467 protects against chronic cadmium-induced mouse kidney injury by restoring autophagy process

In the kidney, disturbance of calcium homeostasis can cause renal hemodynamic changes, leading to glomerulonephritis, tubular damage and renal vascular disease, and thus promotes the development of chronic kidney disease (CKD). Cadmium (Cd) is a toxic heavy metals proved to induce disturbances of calcium homeostasis and nephrotoxicity. Calcium sensing receptor (CaSR) is abundantly expressed in the kidney and plays an important role in maintaining body calcium homeostasis. Our previous study suggested that the activation of CaSR could act as a protective pathway to reduce Cd-induced cytotoxicity in renal proximal tubular cells. However, its application in animal models, its treatment efficacy and underlying mechanisms are still unclear. Therefore, an in vivo animal model (ICR male mouse, n = 5) subjected to Cd-induced nephrotoxicity was used in this study. In the present study, the results indicated that long-term (4 weeks) but not short-term (7 days) Cd exposure induced kidney injury, including induced glomerular atrophy, renal proximal tubule damage, increased malondialdehyde (MDA) level, elevated urine protein quantity, and upregulated kidney injury molecule 1 (KIM-1). It was further observed that chronic Cd exposure induced inhibition of autophagy flux, which triggered kidney apoptosis and injury. However, NPS R-467 restored Cd-inhibited autophagy flux and reduced Cd-induced kidney apoptosis and injury. Finding from this study indicated that activation of CaSR in prevention from nephrotoxicity and kidney injury caused by Cd, which might be helpful for the treatment of clinical CKD.

Bone Mineral Metabolism Status, Quality of Life, and Muscle Strength in Older People

As the relationship between vitamin D and various diseases or health conditions has become known, interest in the contribution of vitamin D to overall health-related quality of life (QoL) has increased. We examined the relationship between vitamin D status and QoL in 273 participants aged 65 years and older. Serum levels of total calcium, phosphorus, intact parathyroid hormone, albumin, and 25-hydroxyvitaminD3 were analyzed. We also recruited data for QoL, physical activity, nutritional impairment, and muscular strength. Ninety percent of the subjects were classified as vitamin D deficient or insufficient. Participants with higher serum 25(OH)D3, calcium, phosphorous, and Alb levels were significantly less likely to self-report depression or anxiety after adjustment (p = 0.009, p = 0.005, p = 0.003, and p = 0.005, respectively). Additionally, we found an association between lower levels of albumin and self-reported problems with mobility or usual activities (p = 0.01). We also found associations between better muscle strength and higher levels of vitamin D, calcium, phosphorous, and albumin (p = 0.006, p = 0.003, p = 0.004 and p = 0.002, respectively). Overall, our data provide evidence that serum vitamin D and Alb levels are negatively related to self-reported anxiety or depression, usual activities, mobility, and three dimensions of QoL in older adults. Furthermore, vitamin D levels are positively related to hand grip strength in adults over 65 years old.

Correlation Between Serum miR-154-5p and Osteocalcin in Males and Postmenopausal Females of Type 2 Diabetes With Different Urinary Albumin Creatinine Ratios

Purpose: To investigate the serum levels of miR-154-5p, osteocalcin (OC), and other clinical parameters in male and post-menopausal female type 2 diabetes mellitus (T2DM) patients with different urinary albumin creatinine ratio (UACR) levels and to discuss the relationship between miR-154-5p and glycolipid metabolism, bone metabolism, and different urinary albumin excretion rate in T2DM. Methods: Seven hundred thirty-eight T2DM patients were categorized into six groups, including 374 men and 364 post-menopausal women who were sub-divided into three groups based on albumin excretion that involved normal albuminuria, microalbuminuria, and large amount of albuminuria (138, 127, 109, 135, 125, and 104 cases, UACR<30, 30-300, and >300 mg/g, M1, M2, M3, F1, F2, and F3). Measurement of circulating miR-154-5p, OC, and other biochemical indicators were performed by real-time PCR, ELISA, and chemiluminescence assays in T2DM patients and in 141 M0 and 139 F0 control subjects. Results: There are few differences appeared between groups. Comparing with men, women had higher age, waist-to-hip ratio (WHR), adiponectin (ADPN), connective tissue growth factor (CTGF), UACR, procollagen type 1 N-terminal propeptide (P1NP), β-C-terminal telopeptide of type I collagen (β-CTx), OC, and miR-154-5p, but lower FPG, HOMA-IR, and HbA1c. T2DM patients with albuminuria (micro or macro) had lower bone turnover markers (P1NP, β-CTx, and OC) and adiponectin, but higher HbA1c, CTGF, and miR-154-5p. In addition, after regression analysis, UACR was positively correlated with CTGF, HbA1c, and miR-154-5p, and negatively correlated with ADPN and bone turnover markers (P1NP, β-CTx, and OC). However, OC showed a positive correlation with ADPN and other bone turnover markers (P1NP and β-CTx), but negative correlation with CTGF, UACR, and miR-154-5p in all three groups. Conclusion: These findings suggested that increased serum levels of miR-154-5p and decreased OC levels may influence osteogenesis and proteinuria in T2DM and may identify novel targets for diagnosis and treatment of diabetic kidney disease and osteoporosis.

Hepatic Osteodystrophy-Molecular Mechanisms Proposed to Favor Its Development

Almost all patients with chronic liver diseases (CLD) show altered bone metabolism. Depending on the etiology, this manifests in a severe osteoporosis in up to 75% of the affected patients. Due to high prevalence, the generic term hepatic osteodystrophy (HOD) evolved, describing altered bone metabolism, decreased bone mineral density, and deterioration of bone structure in patients with CLD. Once developed, HOD is difficult to treat and increases the risk of fragility fractures. Existing fractures affect the quality of life and, more importantly, long-term prognosis of these patients, which presents with increased mortality. Thus, special care is required to support the healing process. However, for early diagnosis (reduce fracture risk) and development of adequate treatment strategies (support healing of existing fractures), it is essential to understand the underlying mechanisms that link disturbed liver function with this bone phenotype. In the present review, we summarize proposed molecular mechanisms favoring the development of HOD and compromising the healing of associated fractures, including alterations in vitamin D metabolism and action, disbalances in transforming growth factor beta (TGF-β) and bone morphogenetic protein (BMP) signaling with histone deacetylases (HDACs) as secondary regulators, as well as alterations in the receptor activator of nuclear factor kappa B ligand (RANKL)–osteoprotegerin (OPG) system mediated by sclerostin. Based on these mechanisms, we give an overview on the limitations of early diagnosis of HOD with established serum markers.

Vitamin D and cardiovascular disease

Vitamin D, a soluble steroid hormone synthesized in the skin after sun exposure, plays a crucial role in calcium metabolism and is also involved in cardiovascular pathophysiology. The aim of this review is to summarize the available evidence (a) on the association between endogenous vitamin D status and cardiovascular disease, and (b) on the effect of vitamin D supplementation on cardiovascular outcomes. Most studies have shown an inverse association between vitamin D levels and cardiovascular outcomes. Randomized controlled trials, however, do not consistently support a beneficial effect of vitamin D administration on cardiovascular health. Population characteristics, comorbid conditions such as diabetes, the overall population prevalence of cardiovascular disease, vitamin D status and the regimen of vitamin D supplementation may account for the conflicting results.

Cardiac Calcified Amorphous Tumors in a Patient with Hemodialysis for Diabetic Nephropathy

Calcified amorphous tumor (CAT) is a rare, non-neoplastic tumor involving calcium deposition in amorphous materials. Although its etiology is unknown, cases have frequently been reported in patients with hemodialysis for chronic kidney disease. We herein describe a case of cardiac CAT in a 64-year-old woman who had been on hemodialysis for diabetic nephropathy for 20 years, and the findings of the present patient, in association with the findings of previous case reports, suggest that end-stage renal disease seems to play an important role in the onset of CAT, especially in CAT formation at the mitral annulus, which appears to differ from CAT occurring at other sites.

Analysis of mandibular changes using panoramic-based indices in patients with chronic renal failure

INTRODUCTION

Chronic renal failure (CRF) is a progressive disease affecting many systems and causing dental and periodontal problems, in particular a decrease or loss in the amount of cortical bone that is visible on radiographs. Panoramic radiography is useful for determining these changes. The aim of this study was to evaluate cortical parts of the mandible using panoramic-based indices in patients with CRF.

METHODS

70 subjects with CRF were included in the study. The measurements of panoramic indices were made according to the visibility (mandibular cortical index, MCI) and thickness (mental index, MI) of the inferior cortex of the mandible. Then, these indices, obtained from 70 healthy controls of the same age and gender, were assessed and the results were compared. The effects of dental status and hemodialysis duration on MCI and MI were also investigated.

RESULTS

The frequency of an eroded cortex was significantly elevated in patients with CRF (p<0.05). The mean MI was lower in patients with CRF than in healthy subjects (5.53 ± 1.62 and 5.73 ± 1.31 mm, respectively), but the difference was not statistically significant (p>0.05). No correlation was found between hemodialysis duration and mandibular indices (p>0.05). Dental status was not associated with mandibular indices (p>0.05).

CONCLUSIONS

These results suggest that MCI might be a useful radiographic parameter for evaluating changes occurring in the cortical parts of the mandible in CRF patients. Clinicians should be aware of these changes while planning invasive dental treatments in CRF patients.

Electrolyte and Acid-Base Disorders in Chronic Kidney Disease and End-Stage Kidney Failure

The kidneys play a pivotal role in the regulation of electrolyte and acid-base balance. With progressive loss of kidney function, derangements in electrolytes and acid-base inevitably occur and contribute to poor patient outcomes. As chronic kidney disease (CKD) has become a worldwide epidemic, medical providers are increasingly confronted with such problems. Adequate diagnosis and treatment will minimize complications and can potentially be lifesaving. In this review, we discuss the current understanding of the disease process, clinical presentation, diagnosis and treatment strategies, integrating up-to-date knowledge in the field. Although electrolyte and acid-base derangements are significant causes of morbidity and mortality in CKD and end-stage renal disease patients, they can be effectively managed through a timely institution of combined preventive measures and pharmacological therapy. Exciting advances and several upcoming outcome trials will provide further information to guide treatment and improve patient outcomes.

Induction of renal senescence marker protein-30 (SMP30) expression by testosterone and its contribution to urinary calcium absorption in male rats

The aim of this study was to investigate the involvement of androgen, mainly testosterone, in the expression of renal senescence marker protein-30 (SMP30) in male rats. We found that the renal SMP30 expression was up-regulated by endogenous testosterone stimulation during puberty. Interestingly, androgen-deficient orchidectomized (ORX) rats exhibited lower SMP30 mRNA and protein expression in the kidney, and that was restored by testosterone propionate (TP) replacement. Abrogation of androgen receptor (AR) activity by co-treatment with flutamide abolished testosterone-induced SMP30 expression in the kidney as well as in the NRK52E cells. However, SMP30 expression was unaltered in the liver of ORX rats. We also showed a positive correlation between renal SMP30 expression and plasma testosterone level during the aging process. TP-induced SMP30 expression in ovariectomized (OVX) rats was observed and was an evidence to explain the gender difference of SMP30 levels. Immunofluorescence assay showed that renal SMP30 was specifically expressed in the proximal tubular segments of the kidney. The urinary Ca(2+) level was increased in both ORX and male aging rats. Taken together, our results indicate a novel role of testosterone in regulating SMP30 expression specifically in the kidney to contribute to urinary calcium absorption.

The association of neutrophil/lymphocyte ratio and platelet/lymphocyte ratio with clinical outcomes in geriatric patients with stage 3-5 chronic kidney disease

OBJECTIVE

The purpose of this study was to investigate the association of the neutrophil/lymphocyte ratio and platelet/lymphocyte ratio with the clinical outcomes in geriatric patients with stage 3-5 chronic kidney disease (CKD).

MATERIAL AND METHODS

A total of 165 patients over the age of 65, with stage 3-5 CKD, were enrolled in the study. The primary endpoints were all-cause of deaths and requirement of renal replacement therapy. The patients were divided into two groups according to delta neutrophil/lymphocyte ratio such as increased (group 1) and decreased or stable (group 2) groups.

RESULTS

The mean age was 73.8 ± 6.1 years and the mean follow-up was 30 ± 13 months. Thirty-one (18.7%) patients died during the follow-up period and 21 (13.4%) patients required renal replacement therapy. The neutrophil/lymphocyte ratio increased in 95 (57.5%) patients. The mortality rate (24.2%, 11.4%; p = 0.03) and requirement of renal replacement therapy (19.1%, 5.7%; p = 0.01) were higher in group 1 compared to group 2. In the Cox regression analysis, the basal neutrophil/lymphocyte ratio was the independent predictor of death (HR: 1.23 (95% CI 1.02-1.47), p = 0.02), and the basal eGFR was the independent predictor of requirement of renal replacement therapy (HR:0.938, 95% CI: 0.888-0.991, p = 0.02). However, platelet/lymphocyte ratio was not associated with death and requirement of renal replacement therapy independently.

CONCLUSION

The neutrophil/lymphocyte ratio predicts all-cause of mortality in geriatric patients with chronic kidney disease.

Crucial Role of Vitamin D in the Musculoskeletal System

Vitamin D is well known to exert multiple functions in bone biology, autoimmune diseases, cell growth, inflammation or neuromuscular and other immune functions. It is a fat-soluble vitamin present in many foods. It can be endogenously produced by ultraviolet rays from sunlight when the skin is exposed to initiate vitamin D synthesis. However, since vitamin D is biologically inert when obtained from sun exposure or diet, it must first be activated in human beings before functioning. The kidney and the liver play here a crucial role by hydroxylation of vitamin D to 25-hydroxyvitamin D in the liver and to 1,25-dihydroxyvitamin D in the kidney. In the past decades, it has been proven that vitamin D deficiency is involved in many diseases. Due to vitamin D’s central role in the musculoskeletal system and consequently the strong negative impact on bone health in cases of vitamin D deficiency, our aim was to underline its importance in bone physiology by summarizing recent findings on the correlation of vitamin D status and rickets, osteomalacia, osteopenia, primary and secondary osteoporosis as well as sarcopenia and musculoskeletal pain. While these diseases all positively correlate with a vitamin D deficiency, there is a great controversy regarding the appropriate vitamin D supplementation as both positive and negative effects on bone mineral density, musculoskeletal pain and incidence of falls are reported.

The osseous and dental changes of patients with chronic renal failure by CBCT

OBJECTIVES

The aim of the present study was to evaluate the osseous changes of the jaws of patients with chronic renal failure (CRF) by CBCT.

METHODS

On CBCT scans obtained from 15 patients with CRF and 15 control patients (7 males and 8 females), the mean was calculated for the antegonial index (AI), mental index (MI), panoramic mandibular index (PMI) and mandibular cortical index (MCI). The MI, AI and PMI, pulp chamber size, number of teeth with pulp calcification and lamina dura loss were compared using the paired t-test, and the MCI values were analysed using the χ(2) test.

RESULTS

There were no statistically significant differences in the PMI, MI and AI values in patients with CRF and the control group. With regard to MCI, the cortical margins of the mandible were more porous in patients with CRF than in the control group, and also soft-tissue calcifications, lamina dura loss and radiolucent defects were more common in patients with CRF. There were no statistically significant differences in pulp chamber size and pulp calcifications between patients with CRF and the control group.

CONCLUSIONS

Radiographic changes in the jawbones of patients with CRF may be commonly seen. CBCT is a valuable diagnostic tool for the evaluation of osseous findings, pulp chamber, soft-tissue calcifications and MCIs and allows indices measurement in three dimensions without any superposition.

Mood disorder as a manifestation of primary hypoparathyroidism: a case report

Introduction

Primary hypoparathyroidism is a rare condition caused by parathyroid hormone deficiency and characterized by hypocalcemia. The clinical manifestations of primary hypoparathyroidism include tetany, seizures, paresthesias, dementia, and parkinsonism. Psychiatric manifestations such as mood disorders are unusual and may constitute a major diagnostic challenge, especially if the typical manifestations caused by hypocalcemia are absent.

Case presentation

The patient was a 22-year-old Caucasian man with a history of chronic omeprazole use and periodic seizures, who presented to the emergency department of a secondary hospital in Southern Brazil with symptoms of major depression (sadness, anhedonia, loss of appetite, insomnia, and fatigue) associated with paresthesias affecting his toes. The initial electrocardiogram revealed a prolonged QTc interval. A computed tomography scan of his brain revealed bilateral, nonenhancing hyperdense calcifications involving the putamen and caudate nucleus. An electroencephalogram showed generalized bursts of slow spikes. Blood laboratory study results indicated serum hypocalcemia, hypomagnesemia, and hyperphosphatemia associated with a low parathyroid hormone level. His serum levels of albumin, 25-hydroxyvitamin D, thyroid-stimulating hormone, T3 and T4 thyroid hormones, as well as the results of kidney function tests, were normal. The definitive diagnosis was primary hypoparathyroidism with psychiatric manifestations due to chronic hypomagnesemia induced by proton pump inhibitor use.

Conclusions

In some cases, to differentiate between a primary psychiatric disorder and primary hypoparathyroidism with neuropsychiatric symptoms may represent a challenge given that the classical manifestations of hypocalcemia, especially tetany, may be absent in the setting of chronic hypoparathyroidism. Clinicians and psychiatrists should consider primary hypoparathyroidism part of the differential diagnosis during the evaluation of patients with mood symptoms, especially in the context of atypical presentations associated with hypocalcemia.

Chronic CCl4 intoxication causes liver and bone damage similar to the human pathology of hepatic osteodystrophy: a mouse model to analyse the liver-bone axis

Patients with chronic liver diseases frequently exhibit decreased bone mineral densities (BMD), which is defined as hepatic osteodystrophy (HOD). HOD is a multifactorial disease whose regulatory mechanisms are barely understood. Thus, an early diagnosis and therapy is hardly possible. Therefore, the aim of our study consisted in characterizing a mouse model reflecting the human pathomechanism. Serum samples were collected from patients with chronic liver diseases and 12-week old C57Bl6/N mice after 6-week treatment with carbon tetrachloride (CCl4). Repetitive injections of CCl4 induced liver damage in mice, resembling liver fibrosis in patients, as assessed by serum analysis and histological staining. Although CCl4 did not affect primary osteoblast cultures, μCT analysis revealed significantly decreased BMD, bone volume, trabecular number and thickness in CCl4-treated mice. In both HOD patients and CCl4-treated mice, an altered vitamin D metabolism with decreased CYP27A1, CYP2R1, vitamin D-binding protein GC and increased 7-dehydrocholesterol reductase hepatic gene expression, results in decreased 25-OH vitamin D serum levels. Moreover, both groups exhibit excessively high active transforming growth factor-beta (TGF-β) serum levels, inhibiting osteoblast function in vitro. Summarizing, our mouse model presents possible mediators of HOD, e.g. altered vitamin D metabolism and increased active TGF-β. Liver damage and significant changes in bone structure and mineralization are already visible by μCT analysis after 6 weeks of CCl4 treatment. This fast response and easy transferability makes it an ideal model to investigate specific gene functions in HOD.

Vascular calcification in Mexican hemodialysis patients

BACKGROUND AND AIMS

Vascular calcification (VC) is a predictor of poor survival and cardiovascular outcome in end-stage renal disease (ESRD) patients; however, there is scarce information of VC in Latin America, and virtually no data in our setting. We undertook this study to evaluate the prevalence and characteristics of VC in a hemodialysis (HD) population from western Mexico and to determine possible associated factors.

METHODS

This was a cross-sectional study performed in 52 patients. VC was evaluated using plain X-ray films (Adragao's score) of hands and pelvis; clinical and biochemical variables were also collected. Statistical analysis was carried out with Student t and χ(2) tests performed as appropriate and logistic regression to determine predictors of VC.

RESULTS

Mean age was 43 years, 48% were female, 23% had diabetes mellitus (DM), and median time on dialysis was 46 months. Percentage prevalence was 52% with a mean calcification score of 2.0 ± 2.6; 23% of patients had severe calcification. VC was present in about 23-37% among the different vascular territories evaluated (radial, digital, femoral and iliac). Patients with calcification were significantly older, had a higher frequency of DM, higher alkaline phosphatase and lower HDL lipoproteins than those without VC. In the multivariate analysis, VC in these patients was significantly predicted only by an older age (OR [95% CI]: 1.15 [1.01-1.31], p = 0.04); lower HDL-cholesterol and higher alkaline phosphatase were marginal predictors.

CONCLUSIONS

Half of our HD patients had VC. Territories of radial, iliac, femoral and digital arteries were roughly equally affected, and 25% of patients had a calcification considered as severe. Older age was the only significant predicting variable for VC, with low HDL-cholesterol and high alkaline phosphatase as marginal predictors.