Treatment patterns and outcomes in light chain amyloidosis: An institutional registry of amyloidosis report in Argentina

Light chain (AL) amyloidosis is a form of systemic amyloidosis, causing organ dysfunction, mainly affecting the heart and kidney. Patient-tailored and risk-adapted decision making is critical in AL amyloidosis management. There is limited real-world evidence data from Argentina and Latin America regarding the treatment approaches for AL amyloidosis. This retrospective cohort study aimed to describe the treatment patterns and outcomes in adult patients (>18 years) diagnosed with AL amyloidosis at the Hospital Italiano in Buenos Aires, Argentina, using a 10-yearfollow-up data (June 1, 2010 to May 31, 2019) from the institutional registry of amyloidosis (IRA). The study population had a mean age of 63 years and 54.4% weremale. Heart and kidney were the most frequently affected organs. Of the 90 eligible patients included in the study, 70underwent treatment. Bortezomib-based regimen was the preferred first-line treatment (75.7% patients). Overall,54.4% of the patients presented a deep response (complete or very good partial response). Median overall survival (OS) was 5years, the 1-year OS and progression free survival rates were 80% (95% confidence interval [CI]: 68–87) and 80% (95%CI 68–87)), respectively. This study provides vital real-world evidence for the long-term treatment patterns and survival in a large cohort of AL amyloidosis patients in Argentina.

[Recommendations for the treatment of AL amyloidosis]

INTRODUCTION

Immunoglobulin light chain (AL) amyloidosis is a rare disease. Treatment is challenging, justified in part by systemic compromise and limited scientific evidence.

OBJECTIVES

Develop evidencebased recommendations that allow adequate treatment of patients with amyloidosis AL.

METHODS

A list of PICO format questions focused on the effectiveness and safety of amyloidosis AL treatment was generated. PubMed, Cochrane and Epistemonikos were searched. The levels of evidence and grades of recommendation were based on the GRADE system.

RESULTS

11 recommendations were generated. In selected patients with amyloidosis AL, autologous hematopoietic stem cell transplantation (ASCT) is recommended after induction with bortezomibbased regimens and conditioning with melphalan, since it could deepen the hematological and organ response, its durability and improve survival. In patients not eligible for ASCT, first-line treatment with bortezomib-based regimens is recommended, since it is likely to achieve a higher rate of hematological and organ response and improve survival. In patients with a contraindication or inaccessibility to bortezomib, treatment with alkylating agents and corticosteroids is recommended, since they are likely to achieve haematological and organ response and improve survival.

DISCUSSION

These treatment recommendations are based on the available evidence and the experience of the panel of experts, in a scenario of limited available resources, according to developing countries.

Vascular inflammation and impaired reverse cholesterol transport and lipid metabolism in obese children and adolescents

BACKGROUND AND AIMS

Childhood obesity is associated to complications such as insulin resistance and dyslipidemia. High density lipoproteins (HDL) constitute the only lipoprotein fraction with ateroprotective properties. The aim of the present study was to analyze inflammatory markers, carbohydrate metabolism, lipid profile and HDL functionality in obese children and adolescents compared to healthy controls.

METHODS AND RESULTS

Twenty obese children and adolescents (Body mass index z score >3.0) (9-15 years old) and 20 age and sex similar controls were included in the study. Triglyceride (TG), total cholesterol (TC), HDL-C, LDL-C, apolipoproteins (apo) A-I and B, glucose and insulin levels were quantified. Lipid indexes and HOMA-IR were calculated. Cholesterol efflux (CEC), lipoprotein associated phospholipase A₂ (Lp-PLA₂), lecithin-cholesterol acyl transferase (LCAT) and cholesteryl ester transfer protein, plus paraoxonase and arylesterase (ARE) activities were evaluated. Obese children and adolescents showed significantly higher TG [69 (45-95) vs 96 (76-121); p < 0.05], non-HDL-C [99 ± 34 vs 128 ± 26; p < 0.01], TC/HDL-C [2.8 ± 0.6 vs 4.7 ± 1.5; p < 0.01], TG/HDL-C [1.1 (1.0-1.8) vs 2,2 (1.4-3.2); p < 0.01], and HOMA-IR [1.5 (1.1-1.9) vs. 2.6 (2.0-4.5); p < 0.01] values, plus Lp-PLA₂ activity [8.3 ± 1.9 vs 7.1 ± 1.7 umol/ml.h; p < 0,05] in addition to lower HDL-C [57 ± 10 vs 39 ± 9; p < 0.01], apo A-I [143 ± 25 vs 125 ± 19; p < 0.05], and CEC [6.4 (5.1-6.8) vs. 7.8 (5.7-9.5); p < 0.01] plus LCAT [12.6 ± 3.3 vs 18.7 ± 2.6; p < 0.05] and ARE [96 ± 19 vs. 110 ± 19; p < 0.05] activities. Lp-PLA₂ activity correlated with LDL-C (r = 0.72,p < 0.01), non-HDL-C (r = 0.76,p < 0.01), and apo B (r = 0.60,p < 0.01). LCAT activity correlated with triglycerides (r = -0.78,p < 0.01), HDL-C (r = 0.64,p < 0.01), and apo A-I (r = 0.62, p < 0.05). ARE activity correlated with HDL-C (r = 0.32,p < 0.05) and apoA-I (r = 0.43,p < 0.01). CEC was negatively associated with BMI z-score (r = -0.36,p < 0.05), and triglycerides (r = -0.28,p < 0.05), and positively with LCAT activity (r = 0.65,p < 0.05). In multivariate analysis, BMI z-score was the only parameter significantly associated to CEC (r2 = 0.43, beta = -0.38, p < 0.05).

CONCLUSION

The obese group showed alterations in carbohydrate and lipid metabolism, which were associated to the presence of vascular specific inflammation and impairment of HDL atheroprotective capacity. These children and adolescents would present qualitative alterations in their lipoproteins which would determine higher risk of suffering premature cardiovascular disease.

[Practice guideline for the treatment of familial amyloid polyneuropathy]

This clinical practice guideline for the treatment of familial amyloid polyneuropathy is based on the best available evidence of clinical effectiveness. A list of questions was generated with a PICO format focused on the effectiveness and safety of the treatment of familial amyloid polyneuropathy. The search was carried out in PubMed, Cochrane and Epistemonikos. The levels of evidence and grades of recommendation were based on the GRADE system. Recommendations were graded according to their direction and their strength and were evaluated with the GLIA tool for their implementation. In patients with familial amyloid polyneuropathy and stage I and II neuropathy, it is suggested: inotersen 300 mg subcutaneous weekly or patisirán 0.3 mg/kg intravenously once every 3 weeks, since they probably stabilize or slow the progression of neuropathy and worsening quality of life (moderate quality of evidence; strength of recommendation weak). In patients with familial amyloid polyneuropathy and stage I neuropathy, treatment with tafamidis 20 mg orally, once a day, is suggested, as it could slow the progression of neuropathy and worsen quality of life (low quality of evidence; strength of recommendation weak). In patients with familial amyloid polyneuropathy and symptomatic neuropathy and in the absence of other treatments with approved efficacy, treatment with oral diflunisal 250 mg twice daily is suggested, as it could prevent the progression of neuropathy (quality evidence low; strength of recommendation weak).

Epidemiology of variant transthyretin amyloidosis at a reference center in Argentina

Background

In Argentina, there is limited data of prevalence of variant transthyretin amyloidosis (ATTRv) and phenotype‐genotype correlation. The laboratory of Hospital Italiano de Buenos Aires (HIBA) is a reference center for transthyretin (TTR) gene sequencing. The Institutional Amyloidosis Registry (RIA) enable us to characterize people with ATTRv. Our aim was to describe the prevalence of TTR mutations at a reference center in Argentina and the phenotypic presentations of patients with ATTRv included in an institutional registry.

Methods

Retrospective cohort study of consecutive patients with genetic variants in the TTR gene identified from 2012 to 2019 in the laboratory. We collected all phenotypic characteristics of patients who were clinically evaluated by HIBA doctors.

Results

Five hundred seventy‐six patients tested, 141 positive: p.Val50Met 107, p.Thr80Ala 16, p.Ala117Ser 9, p.Phe84Leu 2, p.Ile127Val 2, p.Tyr134Cys 2, p.Ala56Pro 2, p.Val142Ile 1. Only 20 patients were clinically evaluated. The mean age at diagnosis was 54 years; 70% had family history with a pedigree median of 4. Mutations were p.Thr80Ala 9, p.Val50Met 6, p.Ala56Pro 2, p.Val142Ile 1, p.Phe84Leu 1, and p.Tyr134Cys 1. Eleven patients presented polyneuropathy, 11 had gastrointestinal compromise, six patients had autonomic compromise, six presented cardiac symptoms and four patients presented ocular involvement.

Conclusion

We present the first prevalence report of TTR mutations in a reference center of amyloidosis in Argentina. The most frequent genetic variant was p.Val50Met. Our data show considerable phenotypic heterogeneity in the patients with ATTRv.

Effect of Tocilizumab on LDL and HDL Characteristics in Patients with Rheumatoid Arthritis. An Observational Study

BACKGROUND

In patients with rheumatoid arthritis (RA), qualitative alterations of low and high-density lipoproteins (LDL and HDL, respectively) might partially explain their increased cardiovascular risk. Tocilizumab has been associated with an increase in lipids, including triglyceride (TG) and cholesterol levels. The aim of this study is to evaluate the effect of tocilizumab on certain LDL and HDL characteristics (oxidized LDL levels, HDL-associated enzymes, chemical composition of both total HDL and HDL3c subpopulation, and their capacity to promote cellular cholesterol efflux) at baseline and 3 months after the start of treatment in patients with RA.

METHODS

Twenty-eight RA patients (ACR/EULAR 2010 criteria) with indication of treatment with tocilizumab were included in the present study. Clinical assessment [Health assessment questionnaire (HAQ)], disease activity score 28 (DAS28), high-sensitivity C reactive protein (hsCRP) concentration, lipid profile, and lipoprotein (a) [Lp(a)] levels were evaluated in all patients at baseline and after 3 months of treatment with tocilizumab. Lipoprotein characteristics were evaluated through the levels of oxidized LDL (OxLDL), the activity of paraoxonase (PON) 1, the composition of total HDL and small, dense HDL3c subpopulation, and their ability to promote cellular cholesterol efflux.

RESULTS

After 3 months of treatment with tocilizumab, HAQ (- 23%, p < 0.05), DAS28 (- 49%, p < 0.001), and hsCRP (- 94%, p < 0.01) levels decreased significantly. Total cholesterol (TC), LDL-C, non-HDL-C, and apo B levels showed a significant increase after treatment (TC: + 7.0%, p < 0.01; LDL-C: + 10%, p < 0.01; non-HDL-C: + 9.9%, p < 0.01; and apo B: + 9.6%, p < 0.05). Decreases in Lp(a) and OxLDL levels were also observed after treatment [Lp(a): - 50%, p < 0.01; and oxLDL: - 5.4%, p < 0.05]. The latter was in accordance with the increment detected in PON activity. No changes were observed in HDL capacity to promote cholesterol efflux (p > 0.05) in the whole group.

CONCLUSIONS

Treatment with tocilizumab reduced hsCRP levels and displayed positive effects on certain lipoprotein-related parameters, such as a potent decrease inLp(a) and a reduction in OxLDL levels. Moreover, HDL capacity to promote cellular cholesterol efflux was maintained after 3 months of treatment.

Effect of Roux-en-Y Gastric Bypass on Lipoprotein Metabolism and Markers of HDL Functionality in Morbid Obese Patients

PURPOSE

Morbid obesity represents the most severe form of obesity and surgical intervention would be its only successful treatment. Bariatric surgery could generate modifications in carbohydrate metabolism and in lipid profile plus lipoprotein-associated proteins and enzymes, such as lipoprotein-associated phoslipase A₂ (Lp-PLA₂), cholesteryl ester transfer protein (CETP), and paraoxonase (PON) 1. The aim of the present study was to analyze changes in inflammation markers, carbohydrate metabolism, and lipid parameters in patients who underwent bariatric surgery.

METHODS

Thirty-seven patients with morbid obesity were recruited. Evaluations were performed before (T0) and 1 (T1) and 6 (T2) months after surgery. Glucose, insulin, high-sensitivity C-reactive protein (hsCRP), triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, apolipoproteins (apo) A-I, and B plus Interleukin 1β and 6 levels in addition to CETP, Lp-PLA2, and PON 1 activities were determined.

RESULTS

Body mass index decreased at T1 and T2 (p < 0.01). An improvement in all markers of insulin resistance (p < 0.05) was observed at T1. hsCRP levels diminished at T2 (p < 0.05). Triglyceride levels decreased at T1 and T2 (p < 0.05). HDL-C and apo A-I showed a decrease at T1 which was completely reversed at T2 (p < 0.05). Lp-PLA₂ activity increased at T1, which was reversed at T2 (p < 0.05), and CETP activity was diminished at T2 (p < 0.05). PON and ARE activities decreased at T1 and partially recovered at T2 (p < 0.05).

CONCLUSIONS

These results would be indicative of a favorable effect of bariatric surgery on markers of carbohydrate metabolism and cardiovascular disease lipid risk factors.

[AA amyloidosis. A single institution cohort study]

There is limited epidemiological information on AA amyloidosis in Argentina, so the objective of this study was to describe the epidemiological characteristics of this disease in a tertiary hospital in our country. We designed a prospective clinical cohort of all consecutive patients with AA amyloidosis confirmed by immunohistochemistry in tissue from the Institutional Registry of Amyloidosis of the Hospital Italiano de Buenos Aires, in the period 04/01/2012- 12/31/2017. Of the 121 patients in the registry, 18 were included with AA for the analysis. Of the total included, 50% (9) were female, with a median age of 53.5 (interquartile range, RII 46-61) years. The 88.9% (16) of cohort presented renal compromise, all had proteinuria, and 6 required dialysis. Six had amyloid infiltration of the digestive system. The latency between the onset of the underlying disease and the diagnosis of AA had a median of 27 (RII 8-35) years. The underlying disease was of inflammatory origin in 6 cases. In 50% (9) of the patients the cause of AA amyloidosis was unknown. In the remaining 50%, these causes resemble those observed in developed countries. Furthermore, our results highlight the importance of their differential diagnosis to identify the most appropriate treatment or follow-up according to the situation presented by each patient.

Markers of inflammation and cardiovascular disease in recently diagnosed celiac disease patients

AIM

To evaluate novel risk factors and biomarkers of cardiovascular disease in celiac disease (CD) patients compared with healthy controls.

METHODS

Twenty adult patients with recent diagnosis of CD and 20 sex, age and body mass index-matched healthy controls were recruited during a period of 12 mo. Indicators of carbohydrate metabolism, hematological parameters and high sensitive C reactive protein were determined. Moreover, lipoprotein metabolism was also explored through evaluation of the lipid profile and the activity of cholesteryl ester transfer protein and lipoprotein associated phospholipase A2, which is also considered a specific marker of vascular inflammation. The protocol was approved by the Ethic Committee from School of Pharmacy and Biochemistry, University of Buenos Aires and from Buenos Aires Italian Hospital, Buenos Aires, Argentina.

RESULTS

Regarding the indicators of insulin resistance, CD patients showed higher plasma insulin levels [7.2 (5.0-11.3) mU/L vs 4.6 (2.6-6.7) mU/L, P < 0.05], increased Homeostasis Model Assessment-Insulin Resistance [1.45 (1.04-2.24) vs 1.00 (0.51-1.45), P < 0.05] and lower Quantitative Sensitive Check index [0.33 (0.28-0.40) vs 0.42 (0.34-0.65), P < 0.05] indexes. Folic acid concentration [5.4 (4.4-7.9) ng/mL vs 12.2 (8.0-14.2) ng/mL, P < 0.01] resulted to be lower and High-sensitivity C reactive protein levels higher (4.21 ± 6.47 mg/L vs 0.98 ± 1.13 mg/L, P < 0.01) in the patient group. With respect to the lipoprotein profile, CD patients showed lower high density lipoprotein-cholesterol (HDL-C) (45 ± 15 mg/dL vs 57 ± 17 mg/dL, P < 0.05) and apo A-I (130 ± 31 mg/dL vs 155 ± 29 mg/dL, P < 0.05) levels, as well as higher total cholesterol/HDL-C [4.19 (3.11-5.00) vs 3.52 (2.84-4.08), P < 0.05] and apo B/apo A-I (0.75 ± 0.25 vs 0.55 ± 0.16, P < 0.05) ratios in comparison with control subjects. No statistically significant differences were detected in lipoprotein-associated lipid transfer protein and enzymes.

CONCLUSION

The presence and interaction of the detected alterations in patients with CD, would constitute a risk factor for the development of atherosclerotic cardiovascular disease.

Poor glycemic control in type 2 diabetes enhances functional and compositional alterations of small, dense HDL3c

High-density lipoprotein (HDL) possesses multiple biological activities; small, dense HDL3c particles displaying distinct lipidomic composition exert potent antiatherogenic activities which can be compromised in dyslipidemic, hyperglycemic insulin-resistant states. However, it remains indeterminate (i) whether such functional HDL deficiency is related to altered HDL composition, and (ii) whether it originates from atherogenic dyslipidemia, dysglycemia, or both. In the present work we analyzed compositional characteristics of HDL subpopulations and functional activity of small, dense HDL3c particles in treatment-naïve patients with well-controlled (n=10) and poorly-controlled (n=8) type 2 diabetes (T2D) and in normolipidemic age- and sex-matched controls (n=11). Our data reveal that patients with both well- and poorly-controlled T2D displayed dyslipidemia and low-grade inflammation associated with altered HDL composition. Such compositional alterations in small, dense HDL subfractions were specifically correlated with plasma HbA1c levels. Further analysis using a lipidomic approach revealed that small, dense HDL3c particles from T2D patients with poor glycemic control displayed additional modifications of their chemical composition. In parallel, antioxidative activity of HDL3c towards oxidation of low-density lipoprotein was diminished. These findings indicate that defective functionality of small, dense HDL particles in patients with T2D is not only affected by the presence of atherogenic dyslipidemia, but also by the level of glycemic control, reflecting compositional alterations of HDL.

Oxidative stress, HDL functionality and effects of intravenous iron administration in women with iron deficiency anemia

BACKGROUND AND AIMS

Iron deficiency anemia (IDA) affects around 20-30% of adults worldwide. An association between IDA and cardiovascular disease (CVD) has been reported. Oxidative stress, inflammation and low concentration of high-density lipoproteins (HDL) were implicated on endothelial dysfunction and CVD in IDA. We studied the effects of iron deficiency and of an intravenous iron administration on oxidative stress and HDL characteristics in IDA women.

METHODS

Two studies in IDA women are presented: a case-control study, including 18 patients and 18 age-matched healthy women, and a follow-up study 72hr after the administration of intravenous iron (n = 16). Lipids, malondialdehyde, cholesteryl ester transfer protein (CETP), paraoxonase-1 (PON-1) and HDL chemical composition and functionality (cholesterol efflux and antioxidative activity) were measured. Cell cholesterol efflux from iron-deficient macrophages to a reference HDL was also evaluated.

RESULTS

IDA patients showed higher triglycerides and CETP activity and lower HDL-C than controls (all p < 0.001). HDL particles from IDA patients showed higher triglyceride content (+30%,p < 0.05) and lower antioxidative capacity (-23%,p < 0.05). Although HDL-mediated cholesterol efflux was similar between the patients and controls, iron deficiency provoked a significant reduction in macrophage cholesterol efflux (-25%,p < 0.05). Arylesterase activity of PON-1 was significantly lower in IDA patients than controls (-16%,p < 0.05). The intravenous administration of iron was associated with a decrease in malondialdehyde levels and an increase in arylesterase activity of PON-1 (-22% and +18%, respectively, p < 0.05).

CONCLUSION

IDA is associated with oxidative stress and functionally deficient HDL particles. It remains to be determined if such alterations suffice to impair endothelial function in IDA.

Altered lipidome and antioxidative activity of small, dense HDL in normolipidemic rheumatoid arthritis: relevance of inflammation

OBJECTIVE

High-density lipoprotein (HDL) particles exert potent antiatherogenic activities, including antioxidative actions, which are relevant to attenuation of atherosclerosis progression. Such activities are enriched in small, dense HDL and can be compromised under conditions of chronic inflammation like rheumatoid arthritis (RA). However, structure-function relationships of HDL largely remain indeterminate.

METHODS

The relationships between HDL structure and function were evaluated in normolipidemic patients with active RA (DAS28 > 3.2; n = 12) and in normolipidemic age-matched controls (n = 10). Small, dense HDL3b and 3c particles were isolated from plasma or serum by density gradient ultracentrifugation and their physicochemical characteristics, lipidome (by LC/MS/MS) and antioxidative function (as protection of normolipidemic LDL from free radical-induced oxidation) were evaluated.

RESULTS

As expected, active RA patients featured significantly elevated plasma levels of high-sensitivity C-reactive protein (hsCRP; p < 0.001) and serum amyloid A (SAA; p < 0.01) relative to controls. Antioxidative activity and weight % chemical composition of small, dense HDL did not differ between RA patients and controls (p > 0.05), whereas HDL phosphosphingolipidome was significantly altered in RA. Subgroup analyses revealed that RA patients featuring high levels of inflammation (hsCRP>10 mg/l) possessed small, dense HDL with reduced antioxidative activities (p < 0.01). Furthermore, antioxidative activity of HDL was inversely correlated with plasma hsCRP (p < 0.01).

CONCLUSIONS

These data revealed that (i) despite normolipidemic state, the lipidome of small, dense HDL was altered in RA and (ii) high levels of inflammation can be responsible for the functional deficiency of small, dense HDL in RA.

Endocrine and inflammatory profiles in type 2 diabetic patients with and without major depressive disorder

Background

There is a high prevalence of depression in individuals with type 2 diabetes mellitus. Depressive disorders are associated with increased medical morbidity and mortality in individuals with diabetes. It has been demonstrated that there is a higher prevalence of diabetic complications among individuals with diabetes and depression compared to those without depression. Several biological alterations have been reported in individuals with depressive disorders, particularly abnormal levels of endocrine-inflammatory markers.

This study aims to determine the prevalence of major depressive disorder (MDD) in type 2 diabetes patients, the prevalence of cardiovascular events in individuals with and without MDD and to compare the endocrine-inflammatory profile between groups.

Methods

The study was approved by the “Comité de Etica de Protocolos de Investigación del Departamento de Docencia e Investigación del Hospital Italiano de Buenos Aires” with the number “1262” and included only patients who provided written informed consent. The study was conducted in accordance with the Declaration of Helsinki and the Habeas Data law on protection of personal data (Law Nª 25326, Argentina).

Type 2 diabetes patients (n = 61) were included and they were classified as having MDD or not according to DSM-IV. Macrovascular disease was obtained from the medical history. Additionally, the intima-media thickness of the common carotid, carotid bifurcations and internal carotid arteries was measured non-invasively by two-dimensional ultrasound imaging. Fasting glucose, fasting lipid profile, inflammatory (CRP, TNF-α) and endocrine (urine free cortisol and saliva cortisol) markers. Student t tests were used to compare means for normally distributed variables and Mann-Whitney test for variables without normal distribution. Relative frequencies were calculated and a chi-square analysis was conducted. Data were expressed as mean ± standard deviation (SD) or median and interquartile range. Multivariable logistic regression was used to determine the relative odds of clinical cardiovascular disease in individuals with compared to those without depression. Differences were considered significant using a two-sided p < 0.05.

Results

21 patients (34%) had MDD and 40 patients (66%) didn’t have MDD. Diabetic patients with MDD had significantly higher CRP levels (4.1(1.9-7.6) vs 1.5(0.5-4.4) mg/l; p = 0.02) and 24-hour urine free cortisol (71.4 ± 21.3 vs 59.8 ± 29.3 ug/24 h; p = 0.03). The other metabolic and inflammatory parameters were not statistically different between groups. There was a significantly higher prevalence of cardiovascular events in individuals with MDD: 38% for the depressive group vs 15% for non-depressive group, p = 0.04). Patients with MDD had a 3.5-fold greater odd of having cardiovascular disease.

Conclusions

Diabetic patients with depression are more likely to have cardiovascular events, and different factors can determine this high association.

Doxorubicin and NRG-1/erbB4-Deficiency Affect Gene Expression Profile: Involving Protein Homeostasis in Mouse

The accumulating evidence demonstrates the essential role of neuregulin-1 signaling in the adult heart, and, moreover, indicates that an impaired neuregulin signaling exacerbates the doxorubicin-mediated cardiac toxicity. Despite this strong data, the specific cardiomyocyte targets of the active erbB2/erbB4 heterodimer remain unknown. In this paper, we examined pathways involved in cardiomyocyte damage as a result of the cardiac sensitization to anthracycline toxicity in the ventricular muscle-specific erbB4 knockout mouse. We performed morphological analyses to evaluate the ventricular remodeling and employed a cDNA microarray to assess the characteristic gene expression profile, verified data by real-time RT-PCR, and then grouped into functional categories and pathways. We confirm the upregulation of genes related to the classical signature of a hypertrophic response, implicating an erbB2-dependent mechanism in doxorubicin-treated erbB4-KO hearts. Our results indicate the remarkable downregulation of IGF-I/PI-3′ kinase pathway and extends our current knowledge by uncovering an altered ubiquitin-proteasome system leading to cardiomyocyte autophagic vacuolization.

High risk of cardiovascular disease in iron overload patients

INTRODUCTION

Iron overload (IO) is defined as an increase in storage iron, regardless of the presence or absence of tissue damage. Whether increased iron stores are involved in the pathogenesis of cardiovascular disease remains controversial.

OBJECTIVES

 To study insulin resistance markers, lipoprotein profile, activities of anti and prooxidant enzymes and cholesteryl ester transfer protein (CETP) in patients with IO.

METHODS

Twenty male patients with IO were compared with 20 sex- and age-matched controls. General biochemical parameters, lipoprotein profile, and activities of paraoxonase 1, employing two substrates, paraoxon (PON) and phenylacetate (ARE), lipoprotein-associated phospholipase A(2) (Lp-PLA(2) ) and CETP were determined.

RESULTS

IO patients showed higher levels of HOMA-IR and triglycerides [median (Q1-Q3)] [128 (93-193) vs. 79(51-91) mg dL(-1) , P < 0·0005] while lower high-density lipoprotein (HDL) cholesterol (mean ± SD) (41 ± 9 vs. 52 ± 10 mg dL(-1) , P < 0·0005) in comparison with controls. Moreover, the triglycerides/HDL-cholesterol [3·2 (2·0-5·1) vs. 1·5 (1·0-1·9), P < 0·0005] ratio and oxidized low-density lipoprotein levels [94 (64-103) vs. 68 (59-70) IU L(-1) , P < 0·05] were increased in the patient group. Although no difference was observed in ARE activity, PON activity was decreased in IO patients [246 (127-410) vs. 428 (263-516) nmol mL(-1) min(-1) , P < 0·05]. In addition, CETP and Lp-PLA(2) activities were also increased in the patients (189 ± 31 vs. 155 ± 36% ml(-1)  h(-1) , P < 0·005; and 10·1 ± 2·9 vs. 8·2 ± 2·4 μmol mL(-1) h(-1) , P < 0·05, respectively). Associations between ferritin concentration and the alterations in lipid metabolism were also found. Multiple regression analyses identified HOMA-IR as independent predictor of CETP activity (B = 65·9, P < 0·0001, r(2) = 0·35), as well as ferritin concentration of Lp-PLA(2) activity (B = 3·7, P < 0·0001, r(2) = 0·40) after adjusting for confounding variables.

CONCLUSIONS

  IO patients presented not only insulin resistance but also metabolic alterations that were related to elevated iron stores and are associated with high risk of cardiovascular disease.

[Increased iron store and its relationship with cardiovascular disease]

In the last years, great advance has been achieved in the control of several of the classic atherogenic risk factors; nonetheless, the incidence of cardiovascular disease (CVD) still remains high. Among the disorders which are associated with CVD, increased iron stores have been described as one of them. Its study gained relevance since the "iron hypothesis", which postulates that low iron levels exert a protective effect on cardiovascular system, was elaborated. In spite of the numerous studies carried out to test this hypothesis, the results have been controversial. On the other hand, much knowledge regarding iron metabolism has been gained since the description of the regulatory hormone, hepcidin. The studies on hepcidin physiologic functions allowed the elaboration of new hypothesis that could explain the results formerly conceived as inconsistent. The aim of the present review is to describe, in light of the newest advances in iron metabolism regulation and its association with inflammation, the current state of knowledge regarding the possible role of iron overload as a risk factor of CVD.

A study on strategies for improving growth and body composition after renal transplantation

Allograft function and metabolic effects of four treatment regimens, namely, methylprednisone (MP) standard dose (MP-STD), deflazacort (DFZ), MP-late steroid withdrawal (MP-LSW), and MP-very low dose (MP-VLD), were evaluated in prepubertal patients. MP was decreased by month 4 post-transplantation to 0.2 mg/kg/day in MP-STD and DFZ patients and to <0.1 mg/kg/day in MP-LSW and MP-VLD patients. Starting in month 16 post-transplant, MP was switched to DFZ in the DFZ group and totally withdrawn in the MP-LSW group. Creatinine clearance diminished in the MP-STD and MP-LSW groups from 77 +/- 6 to 63 +/- 6 ml/min/1.73 m(2)and from 103 +/- 5 to 78 +/- 3 ml/min/1.73 m(2), respectively (p < 0.01 and p < 0.001, respectively). Height increased >0.5 SDS only in the MP-LSW and MP-VLD groups. The body mass index and fat body mass for height-age increased only in the MP-STD patients (p < 0.05 and p < 0.01, respectively). Fat body mass decreased in the DFZ group (p < 0.05), total cholesterol and LDL-cholesterol increased in the MP-STD group, while LDL-cholesterol and total cholesterol/HDL-cholesterol ratio decreased in the DFZ group (p < 0.01). Lumbar spine bone mineral density (BMD) for height-age showed an increase in the MP-LSW and MP-VLD groups (p < 0.01). Our data suggest that MP-LSW and MP-VLD strategies improve linear growth, BMD, the peripheral distribution of fat, and preservation of the bone-muscle unit and maintain the normal lipid profile. The MP-LSW patients had a concerning rate of acute rejections and graft function deterioration in prepubertal patients.

Effects of deflazacort vs. methylprednisone: a randomized study in kidney transplant patients

Metabolic effects of deflazacort vs. methylprednisone were studied in prepubertal patients after kidney transplantation. Thirty-one patients participated: 15 received deflazacort and 16 remained on methylprednisone. The study started at a mean of 2.1 years after transplantation, when patients were randomized to either continue with methylprednisone or switch to deflazacort. Height velocity increased more in the deflazacort than in the methylprednisone group only during the first 2 years: 5.4 +/- 0.5 vs. 3.5 +/- 0.3 cm/year, and 4.2 +/- 0.8 vs. 2.2 +/- 0.4 cm/year p=0.007, [by two-way analysis of variance (ANOVA)]. After 2 and 3 years, the number of patients who were overweight increased in the methylprednisone group and decreased in the deflazacort group; p<0.01. Lean body mass increased more in the deflazacort than in the methylprednisone group (p=0.003). Fat body mass increased only in the methylprednisone group (p<0.01). Total cholesterol and low-density-lipoprotein (LDL) cholesterol increased in the methylprednisone group (p<0.05 and p<0.01, respectively). Total and LDL cholesterol were reduced (p<0.01 and p<0.001, respectively), whereas high-density-lipoprotein (HDL) cholesterol increased (p<0.001) during deflazacort therapy. Lumbar spine bone mineral density (BMD) decreased in both groups, but total skeleton BMD decreased only in the methylprednisone group (p<0.001). Finally, normal glucose/insulin ratio, defined as > 7, was associated (p<0.05) with the deflazacort group. Our data suggest that deflazacort therapy might improve linear growth and lean body mass and prevent excessive bone loss and fat accumulation. It also leads to an improvement in lipoprotein profile without reduction in insulin sensitivity.

[Seasonal variations in 25-hydroxyvitamin D in young and elderly and populations in Buenos Aires City]

The purpose of this study was to evaluate the level of hypovitaminosis D in elderly and young outpatients populations of the City of Buenos Aires, and to establish its impact on bone remodeling. A total of 83 elderly and 76 young patients aged 71.9 +/- 8.1 and 29.8 +/- 6.6 years respectively, were evaluated by measuring 25-hydroxyvitamin D, 25 (OH)D, middle-molecular parathyroid hormone, and biochemical measurements of bone and mineral metabolism markers. In winter, insufficient values of 25(OH)D were observed both in elderly and young populations: 14.2% of the elderly and 15.9% of young people showed deficient values of 25(OH)D. In summer, an increase in the two groups was observed. Parathyroid hormone levels were higher in the elderly group. Secondary hyperparathyroidism was reported only in the aged group (28.1% in winter, and 20.5% in summer). The increased levels of parathyroid hormone and the presence of secondary hyperparathyroidism in the elderly would be conditioned by this deficiency and other additional factors such as age, renal insufficiency and nutrition degree. In winter, there was an increase in the bone remodeling markers, with higher values in the elderly group. In the City of Buenos Aires decreased levels of 25(OH)D were seen both in young and elderly individuals, with seasonal variations. Sanitary policies are necessary to prevent hypovitaminosis D, because this condition predisposes for osteoporosis.

Ammonium detoxification performed by porcine hepatocyte spheroids in a bioartificial liver for pediatric use: preliminary report

Bioartificial liver devices are alternative therapies for patients suffering from acute hepatic failure or metabolic defects. Here, we show a bioartificial device, developed with a cartridge used for pediatric hemofiltration and spheroids of porcine hepatocytes housed in the extracapillary space of the cartridge. The cartridge was attached to a robotic arm that supplied a continuous, oscillatory movement. It was connected through the capillary circulation to a neonatal membrane oxygenator contain-ing human blood supplemented with ammonium and diazepam. A decrease in ammonium concentration was observed, reaching an almost 70% decrease upon 9 h of operation. In addition, urea was detected and diazepam metabolism proved from the fourth hour of operation. It is worth mentioning that the system described was assembled with commercially available components for current clinical use. The setup may be done in a short period, thus eliminating long-term culture times and the need for cell anchoring to matrices.

Use of atorvastatin in hyperlipidemic hypertensive renal transplant recipients

The aim of the present short-term study was to evaluate the use of a new HMG-CoA reductase inhibitor, atorvastatin, in the treatment of hyperlipidemia and the effect on blood pressure in a group of hypertensive stable renal transplant recipients with hypercholesterolemia who received kidney grafts before 18 years of age. Eight patients (aged 10.8-30.1 years) with inadequately controlled total cholesterol (TC) levels by a lipid-lowering diet (8 weeks) were treated daily for 12 weeks with atorvastatin at an initial dose of 2.5 mg. The dose was increased monthly by 2.5 mg in order to lower TC levels to less than 200 mg/dl. Serum lipoprotein profile, cyclosporin A (CsA), serum creatinine (SCr), and liver and muscle enzyme levels were measured before starting the lipid-lowering diet, at the start of treatment (baseline), and during treatment. Ambulatory blood pressure monitoring (ABPM) (24-h) was carried out in each patient at both baseline and the end of the follow-up. During the lipid-lowering diet, no significant changes in lipoprotein parameters were observed. Atorvastatin was tolerated well and no clinical side effects were noted during the follow-up. The final dose of atorvastatin ranged from 2.5 to 7.5 mg/day. At the end of the study, TC was reduced by 32.2% ( P<0.05), low-density lipoprotein cholesterol (LDL-C) by 41.8% ( P<0.05), and apo B by 29.5% ( P<0.05). No significant changes in HDL-C, VLDL-C, apolipoprotein AI, and lipoprotein(a) were observed. SCr and CsA levels were unaffected. Overall, no significant changes in mean 24-h, daytime, and nighttime ABPM values between the first and the second recordings were observed. However, both daytime and nighttime systolic and diastolic ABPM values dropped in four patients. In conclusion, low-dose atorvastatin appears to be safe, well tolerated, and effective in the treatment of post-transplant hyperlipidemia. In addition, the capacity of atorvastatin to reduce blood pressure, whether or not related to its lipid-lowering action, deserves further investigation.

Culture of porcine hepatocytes: the dogma of exogenous matrix revisited

The use of exogenous matrices has been described as an essential component in securing the viability and functionality of hepatocytes in vitro whether cultured for extracorporeal devices or cell transplantation. Here we report on the in vitro culture of porcine hepatocytes in polystyrene tissue-culture flasks without exogenous matrices showing adequate attachment and viability. Cell proliferation was evidenced by uptake of 5-bromo-2'-deoxyuridine, with peaks at Days 2 (19.7 +/- 8.5%), 15 (20.8 +/- 3.3%), and 35 (21.4 +/- 0.3%). Detoxification capacity was assessed by determination of monoethylglycinexylidide, a product of lidocaine metabolism (highest value 156.5 +/- 10.1 ng/ml at Day 4), and by diazepam clearance (maximum clearance 66.2% at Day 6). Diazepam metabolite levels were highest at Day 4 both for temazepam and oxazepam (6.5 +/- 0.1 and 0.10 +/- 0.01, respectively). These results suggest that the need for an exogenous matrix to achieve sustained proliferative activity and differentiated hepatocyte function should not necessarily be considered a sine qua non condition.

Hyperhomocysteinemia in stable pediatric, adolescents, and young adult renal transplant recipients

BACKGROUND

High total plasma homocysteine (tHcy) levels are accompanied by an increased risk for premature development of atherosclerosis and atherothrombosis. Adult renal transplant recipients have elevated tHcy levels. Corresponding data in pediatric, adolescent, and young adult renal transplant recipients are scarce. We investigated whether tHcy levels were elevated in stable renal transplant recipients who received kidney grafts before age 18.

METHODS

This cross-sectional study was conducted during routine posttransplantation follow-up. Fasting tHcy levels, serum creatinine, and lipoprotein profile were measured in 38 clinically stable renal transplant recipients with different degrees of renal function. No patient was receiving B vitamin or folic acid supplementation. Estimated glomerular filtration rate (GFR) was assessed according to Schwartz's formula. All patients followed a triple-drug immunosuppressive regimen, with the exception of three patients (deflazacort and azathioprine). Forty-one apparently healthy subjects constituted the control group. tHcy levels were determined by fluorescence polarization immunoassay in an IMx analyzer.

RESULTS

Mean tHcy levels in transplant recipients were significantly higher than in controls (16.8+/-8.7 micromol/L and 9.5+/-2.3 micromol/L, respectively; P<0.01). A significant positive correlation between tHcy and serum creatinine levels was observed for both transplant recipients (rS=0.70, P<0.01) and controls (rS=0.54, P<0.01). In transplant recipients, tHcy correlated negatively with estimated GFR (rS=[minus]0.47, P<0.05). Fasting tHcy levels in excess of 14.6 micromol/L (>95th percentile in controls) were present in 19 (50%) patients; 14 of these patients had an estimated GFR<60 ml/min per 1.73 m2. When the renal transplant recipients were analyzed by renal function, mean tHcy was significantly higher in patients with an estimated GFR<60 ml/min per 1.73 m2 compared with patients with an estimated GFR> or =60 ml/min per 1.73 m2 (20.5+/-9.9 vs. 13.2+/-5.8 micromol/L, P<0.01). Both groups were significantly different from controls (P<0.01). No relationship was found between tHcy level and either cumulative cyclosporine or cumulative methylprednisone doses. No differences were observed in tHcy levels or lipoprotein profile between patients who were receiving deflazacort and those on methylprednisone.

CONCLUSIONS

Hyperhomocysteinemia in renal transplant recipients is a common condition. Testing for fasting tHcy level might be a useful tool to identify patients at increased risk for development of vascular disease.

Effect of deflazacort versus methylprednisone on growth, body composition, lipid profile, and bone mass after renal transplantation. The Deflazacort Study Group

Kidney function, growth velocity, weight/height ratio, body composition, lipid profile, and bone mass were studied in a randomized, multicenter trial of deflazacort versus methylprednisone in 27 prepubertal patients with kidney transplantation. Methylprednisone (0.20+/-0.03) was replaced by deflazacort (13 patients, 0.30+/-0.03 mg/kg per day). After 12 months, creatinine clearance decreased significantly only during methylprednisone therapy. Growth velocity increased only in patients treated with deflazacort from 3.3+/-0.6 to 5.6+/-0.5 cm/year. Serum levels of several components of the insulin-like growth factor axis did not change. Weight/height ratio was increased in methylprednisone-treated patients (P<0.05) and decreased in deflazacort-treated patients (P<0.005). Lean body mass increased in both groups (P<0.005). Fat body mass and serum leptin increased only in methylprednisone-treated patients (P<0.025). Total cholesterol and low-density lipoprotein-cholesterol increased in methylprednisone-treated patients by 9.9% (P<0.05) and 12.5% (P<0.025). High-density lipoprotein-cholesterol increased by 21% (P<0.005) and apolipoprotein B decreased by 11% (P<0.005) in deflazacort-treated patients. Total skeleton and lumbar spine bone mineral density decreased in both groups, but at 1 year methylprednisone-treated patients had lost 50% more bone. Bone mineral content decreased only in methylprednisone-treated patients (P<0.01). Our data suggest that substituting deflazacort for maintenance methylprednisone might prevent height loss, excessive bone loss, and fat accumulation; and leads to an improvement in the lipoproteins of these children.

Von Willebrand factor could be an index of endothelial dysfunction in patients with cirrhosis: relationship to degree of liver failure and nitric oxide levels

BACKGROUND/AIMS

The aim of this study was to evaluate the relationship between plasma levels of von Willebrand factor (vWF), a marker of endothelial cell activation, and nitric oxide, a powerful vasodilator synthesized by endothelial cells, in 27 patients with cirrhosis at different stages of the disease. These results were compared with those of age-matched normal, healthy subjects (n=10).

METHODS

vWF:antigen was measured by electro-immunodiffusion test and serum nitrite and nitrate levels, the stable end products of nitric oxide metabolism, were determined by an enzymatic procedure.

RESULTS

vWF:antigen and nitrite/nitrate levels were significantly higher in cirrhotic patients (367+/-185% and 29.3+/-10.8 micromol/l) than in healthy subjects (92+/-20% and 19.2+/-8.3 micromol/l, p<0.05, respectively). Higher levels of vWF:antigen and nitrites/nitrates were observed in patients with more advanced degrees of liver failure, as reflected by quantitative Child-Pugh's score (516+/-154% and 38.3+/-7.8 micromol/l in Child-Pugh > or = 9 vs 227+/-61% and 21.0+/-6.1 micromol/l in Child-Pugh <9, p<0.001, respectively). Moreover, both endothelial-related factors were higher in patients with ascites than those without ascites (543+/-158% and 37.8+/-8.9 micromol/l vs 262+/-103% and 24.4+/-8.8 micromol/l, p<0.001, respectively). In the overall series, a highly significant linear correlation between nitrites/nitrates and vWF:antigen levels was observed in patients with cirrhosis (r=0.79, p<0.001).

CONCLUSIONS

These results support a cirrhosis-related endothelial dysfunction and suggest that plasma vWF measurement could be useful as a marker of endothelial disturbance in patients with cirrhosis.

Effect of therapy with deflazacort on dyslipoproteinemia after pediatric renal transplantation

Deflazacort is an oxazolone compound derived from prednisolone, with similar immunosuppressive action but fewer side effects. Kidney function, weight/height ratio, serum triglycerides, cholesterol, high-density lipoprotein (HDL) cholesterol, very-low-density lipoprotein cholesterol, low-density lipoprotein (LDL) cholesterol, apolipoprotein A, apolipoprotein B, and lipoprotein (a) were studied before and 6 months after substitution of deflazacort (mean +/- SEM, 0.3 +/- 0.1 mg/kg per day) for methylprednisone (0.2 +/- 0.1 mg/kg per day) in 14 patients treated with cyclosporine, aged 3.1 to 20.3 years, 3 years after renal transplantation. Serum creatinine and calculated creatinine clearance did not change significantly, and weight/height ratio decreased from 20.0% +/- 7.1% to 12.5% +/- 6.5% (P < .005) during deflazacort therapy. Total cholesterol was reduced by 15.9% (from 233 +/- 15 mg/dL to 196 +/- 13 mg/dL, P < .01), LDL cholesterol by 25.5% (from 153 +/- 14 mg/dL to 114 +/- 12 mg/dL, P < .01), and TC/HDL cholesterol ratio by 28.3% (from 5.3 +/- 0.4 to 3.8 +/- 0.4, P < .01), whereas HDL cholesterol increased 18% (from 45 +/- 2 mg/dL to 53 +/- 2 mg/dL) and apolipoprotein A by 8.3% (from 122 +/- 5 mg/dL to 132 +/- 5 mg/dL, P < .05) during deflazacort therapy. Our data suggest that substituting deflazacort for maintenance methylprednisone therapy leads to an improvement in the lipoprotein profile of children after renal transplantation.

Serum alkaline phosphatase isoenzymes in hepatobiliary disorders resolved by use of immobilized pH gradients

This new method for fractionating alkaline phosphatase isoforms in hepatobiliary disorders is based on isoelectric focusing on a mixed-type polyacrylamide support containing an immobilized pH gradient with a superimposed carrier-ampholyte gradient. The high-Mr alkaline phosphatase forms typical of hepatobiliary disease (greater than 1 mega-dalton), which cannot migrate into the Immobiline gel, are disaggregated in zwitterionic detergents (the most effective being sulfobetaine 3-12)--20 g/L in the sample, 5 g/L in the gel--suggesting that they are still complexed with membrane fragments or that they tend to aggregate spontaneously in solution. These isoforms focus in the pI 5-6 range (while alkaline phosphatases in normal serum focus in the pI 4-5 interval) in immobilized pH gradients, but behave as strongly acidic components by agarose isoelectric focusing in the presence of carrier ampholytes, suggesting that they are strongly complexed with the latter. On treatment with neuraminidase, the low-pI isoforms in normal serum focus in the pI 5-6 range typical of the hepatobiliary isoforms, suggesting that the latter are poorly glycosylated. By a second-dimension run, in a porosity gradient, followed by activity staining, all alkaline phosphatase forms that have entered the Immobiline gel in the first dimension (normal forms and high-Mr species) exhibit the same Mr (ca. 140,000 Da), suggesting that no new chains are synthesized in hepatobiliary disorders.

Serum alkaline phosphatase isoenzymes in hepatobiliary disorders resolved by use of immobilized pH gradients

This new method for fractionating alkaline phosphatase isoforms in hepatobiliary disorders is based on isoelectric focusing on a mixed-type polyacrylamide support containing an immobilized pH gradient with a superimposed carrier-ampholyte gradient. The high-Mr alkaline phosphatase forms typical of hepatobiliary disease (greater than 1 mega-dalton), which cannot migrate into the Immobiline gel, are disaggregated in zwitterionic detergents (the most effective being sulfobetaine 3-12)--20 g/L in the sample, 5 g/L in the gel--suggesting that they are still complexed with membrane fragments or that they tend to aggregate spontaneously in solution. These isoforms focus in the pI 5-6 range (while alkaline phosphatases in normal serum focus in the pI 4-5 interval) in immobilized pH gradients, but behave as strongly acidic components by agarose isoelectric focusing in the presence of carrier ampholytes, suggesting that they are strongly complexed with the latter. On treatment with neuraminidase, the low-pI isoforms in normal serum focus in the pI 5-6 range typical of the hepatobiliary isoforms, suggesting that the latter are poorly glycosylated. By a second-dimension run, in a porosity gradient, followed by activity staining, all alkaline phosphatase forms that have entered the Immobiline gel in the first dimension (normal forms and high-Mr species) exhibit the same Mr (ca. 140,000 Da), suggesting that no new chains are synthesized in hepatobiliary disorders.