Lipid profile in ?-thalassemia intermedia patients: correlation with erythroid bone marrow activity

Association of thalassemia, hemoglobinopathies, and vitamin D levels with lipid profile in adults: Community-based research in southern Thai population

This study explored the frequency of lipid-lowering drug use in the thalassemia population and investigated the association of thalassemia, hemoglobinopathies, and serum 25(OH)D levels with lipid profile and red blood cell parameters. A combination of cross-sectional and community-based studies was conducted with 615 participants from the southern Thai population. Thalassemia and hemoglobinopathies were diagnosed using hemoglobin analysis and polymerase chain reaction-based methods to genotype globin genes. Biochemical parameters such as lipid profile, fasting blood sugar (FBS), and serum 25(OH)D levels were assessed using standard enzymatic methods and electrochemiluminescence immunoassays. Differences in the means of hematological and biochemical parameters between the thalassemia and non-thalassemia groups were compared and analyzed. A significantly lower frequency of lipid-lowering drug use was observed in the thalassemia group. Thalassemia, with clearly defined abnormalities in red blood cells, is associated with a 4.72-fold decreased risk of taking lipid-lowering drugs. Among thalassemia participants, the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were significantly lower than those in non-thalassemia participants. The prevalence of hypovitaminosis D in carriers of thalassemia and/or hemoglobinopathies in the southern Thai population was 53 % in females and 21 % in males. The highest lipid profile was observed in samples without thalassemia and hypovitaminosis D. The genetics of thalassemia and hemoglobinopathies with obviously abnormal red blood cells could explain the variable lipid levels, in addition to lipid metabolism-related genes and environmental factors. However, the effect of thalassemia on lipid levels in each population may differ according to its prevalence. A larger sample size is required to confirm this association, especially in countries with a high prevalence of thalassemia.

Non-Transferrin-Bound Iron in the Spotlight: Novel Mechanistic Insights into the Vasculotoxic and Atherosclerotic Effect of Iron

Significance: While atherosclerosis is an almost inevitable consequence of aging, food preferences, lack of exercise, and other aspects of the lifestyle in many countries, the identification of new risk factors is of increasing importance to tackle a disease, which has become a major health burden for billions of people. Iron has long been suspected to promote the development of atherosclerosis, but data have been conflicting, and the contribution of iron is still debated controversially. Recent Advances: Several experimental and clinical studies have been recently published about this longstanding controversial problem, highlighting the critical need to unravel the complexity behind this topic. Critical Issues: The aim of the current review is to provide an overview of the current knowledge about the proatherosclerotic impact of iron, and discuss the emerging role of non-transferrin-bound iron (NTBI) as driver of vasculotoxicity and atherosclerosis. Finally, I will provide detailed mechanistic insights on the cellular processes and molecular pathways underlying iron-exacerbated atherosclerosis. Overall, this review highlights a complex framework where NTBI acts at multiple levels in atherosclerosis by altering the serum and vascular microenvironment in a proatherogenic and proinflammatory manner, affecting the functionality and survival of vascular cells, promoting foam cell formation and inducing angiogenesis, calcification, and plaque destabilization. Future Directions: The use of additional iron markers (e.g., NTBI) may help adequately predict predisposition to cardiovascular disease. Clinical studies are needed in the aging population to address the atherogenic role of iron fluctuations within physiological limits and the therapeutic value of iron restriction approaches. Antioxid. Redox Signal. 35, 387-414.

Subclinical atherosclerotic predictive value of inflammatory markers in thalassemia intermedia patients

BACKGROUND

A high incidence of thromboembolic events is observed in thalassemia patients. This study investigated the relationship between carotid intima-media thickness (CIMT) and lipid profile, iron metabolic indices (IMI), and inflammatory markers in β-thalassemia intermedia (β- TI) patients.

PATIENTS AND METHODS

Forty-five β-TI patients at Assiut University Hospital and 34 healthy individuals were enrolled in the study. We measured Lipid profile, IMI, high sensitive CRP (Hs-CRP), and interleukin-6 (IL-6) and compared the results between both groups. We used CIMT measurement as a marker for subclinical atherosclerosis. We used both univariate and multivariate analyses to test relations and independent predictors of CIMT.

RESULTS

β-TI patients had higher CIMT (P = 0.000). CIMT was positively correlated with absolute neutrophil count (ANC) (r = 0.320, p = 0.032), ferritin (r = 0.544, p = 0.000), Hs-CRP (r = 0.603, p = 0.000), and IL-6 (r = 0.520, p = 0.000). Hs-CRP was an independent predictor of CIMT (p = 0.000). Hs-CRP cut off value of 60.4 ug/dl has sensitivity of 63.3% and specificity of 93.3% in predicting premature atherosclerosis.

CONCLUSION

β-TI patients had higher CIMT despite the protective lipid profile. Hs-CRP was an independent predictor of CIMT.

Vasculo-toxic and pro-inflammatory action of unbound haemoglobin, haem and iron in transfusion-dependent patients with haemolytic anaemias

Increasing evidence suggests that free haem and iron exert vasculo‐toxic and pro‐inflammatory effects by activating endothelial and immune cells. In the present retrospective study, we compared serum samples from transfusion‐dependent patients with β‐thalassaemia major and intermedia, hereditary spherocytosis and sickle cell disease (SCD). Haemolysis, transfusions and ineffective erythropoiesis contribute to haem and iron overload in haemolytic patients. In all cohorts we observed increased systemic haem and iron levels associated with scavenger depletion and toxic ‘free’ species formation. Endothelial dysfunction, oxidative stress and inflammation markers were significantly increased compared to healthy donors. In multivariable logistic regression analysis, oxidative stress markers remained significantly associated with both haem‐ and iron‐related parameters, while soluble vascular cell adhesion molecule 1 (sVCAM‐1), soluble endothelial selectin (sE‐selectin) and tumour necrosis factor α (TNFα) showed the strongest association with haem‐related parameters and soluble intercellular adhesion molecule 1 (sICAM‐1), sVCAM‐1, interleukin 6 (IL‐6) and vascular endothelial growth factor (VEGF) with iron‐related parameters. While hereditary spherocytosis was associated with the highest IL‐6 and TNFα levels, β‐thalassaemia major showed limited inflammation compared to SCD. The sVCAM1 increase was significantly lower in patients with SCD receiving exchange compared to simple transfusions. The present results support the involvement of free haem/iron species in the pathogenesis of vascular dysfunction and sterile inflammation in haemolytic diseases, irrespective of the underlying haemolytic mechanism, and highlight the potential therapeutic benefit of iron/haem scavenging therapies in these conditions.

Body Composition in Egyptian Children With Transfusion-dependent Thalassemia: The Impact of Nutrition and Metabolic Profile

BACKGROUND

Growth failure is a common complication in children with beta-thalassemia major (β-TM) that has persisted despite major treatment advances. It could stem from malnutrition, especially in those who live in poor countries and who have inadequate nutrient intake.

AIM

The aim of this study was to assess the influence of nutrition on growth, total body composition, and metabolic profile in Egyptian children with β-TM.

SUBJECTS AND METHODS

This cross-sectional study included 200 children with β-TM and 50 age-matched and sex-matched healthy children. All subjects underwent full clinical assessment, which included assessment of growth and total body composition using anthropometric measurements (weight, height, mid-arm circumference, skinfold thickness, and body mass index) and bioelectric impedance analysis device (TANITA SC330). Nutritional assessment was performed using 24-hour dietary recall. Fasting serum insulin, C-peptide, and fasting serum lipid profile (high-density lipoprotein, low-density lipoprotein, cholesterol, and triglyceride) were measured.

RESULTS

Children with β-TM had a significantly lower mean value of the daily consumption of the studied nutrient elements including kilocalories, protein, carbohydrate, calcium, and phosphorus (P<0.001). β-TM had a negative impact on anthropometric measures; the mean of all measurements recorded in children with β-TM was significantly lower than that in the control group (P<0.001). Children with β-TM had a significant abnormality in lipid profile, with higher triglyceride levels and lower cholesterol, low-density lipoprotein, and high-density lipoprotein than controls. They had significantly lower serum insulin and C-peptide. Age, sex, serum ferritin, and caloric intake have a significant impact on body composition in children with β-TM.

CONCLUSION

Regular assessment of nutrition is crucial for the health of children with β-TM.

Premature atherosclerosis in children with beta-thalassemia major: New diagnostic marker

Background

Early vascular alteration, atherosclerosis and coronary artery disease have emerged as important cardiovascular complications among beta-thalassemia major (B-TM) patients. The aims of the current study were to assess the prevalence of premature atherosclerosis among our B-TM patients, and to investigate the diagnostic value of serum Osteoprotegerin assay as an early biomarker for atherosclerosis.

Methods

This cross-sectional study was conducted at Hematology unit - Pediatric Department, Zagazig University Children Hospital- Egypt in the period from March 2014 to March 2015. A total of 115 children were enrolled in the current study; as sixty-five (65) children with beta thalassemia major aged 5–18 years, on regular blood transfusion regimen represented the patient group. While fifty (50) healthy children, with comparable age and gender, were assigned as control group. All participants were subjected to history taking, thorough clinical examination and laboratory investigations including; complete blood count, liver and kidney function tests, C- reactive protein, lipid profile, serum ferritin and serum Osteoprotegerin (OPG) assay. Also, carotid artery intima media thickness (CAIMT) was performed by duplex ultrasound for patients and controls.

Results

Our B-TM patients were transfusion-dependent for as long as 8.5 ± 3.8 years with significantly higher serum ferritin levels (2490 ± 1579 ng/dl vs 83 ± 32 ng/dl, p = 0.001), C-reactive protein (5.7 ± 5.7 vs 0.9 ± 0.9), liver enzymes and bilirubin when compared to controls. Significantly higher serum triglyceride (128 ± 20 vs 101 ± 7 mg/dL, p = 0.009) and atherogenic index of plasma (0.45 ± 0.12 vs 0.22 ± 0.04, p = 0.001) were recorded in patients than comparisons. On the contrary, total serum cholesterol (116 ± 16 vs 143 ± 5, p < 0.001), low density lipoprotein-cholesterol (LDL-C) (44 ± 9 vs 73 ± 6, p < 0.001) and high density lipoprotein cholesterol (HDL-C) (39 ± 2 vs 61 ± 5, p < 0.001), were significantly lowered in patients versus normal peers. Carotid arteries intima media thickness (CAIMT) of both side were significantly increased for patients (Rt 0.62 ± 0.2 vs. 0.29 ± 0.07 mm, p = 0.001 & Lt 0.66 ± 0.17 vs 0.29 ± 0.05 mm, p = 0.001) when compared with healthy controls, and showed positive correlation with, serum triglyceride, atherogenic index of plasma, and serum Osteoprotegerin levels. ELISA assay of serum Osteoprotegerin (OPG) revealed significantly higher levels for thalassemia patients than matched healthy controls (427 ± 102 vs. 324 ± 126 pg/ml, p = 0.02). Of particular interest is the obvious positive correlation between OPG levels and CAIMT of both sides (Rt r 0.54, p = 0.001 &Lt r 0.479, p = 0.001) and also with serum triglycerides (r 0.374, p = 0.03).

Conclusions

Subclinical atherosclerosis started prematurely in children with beta- thalassemia. Carotid artery intima media thickness represented a simple, accurate and non-invasivemodality for early detection ofatherosclerosis. It was correlated well with serum Osteoprotegerin; this finding highlighted the possible validity of OPG assay as an early predictor of atherosclerosis in thalassemia children.

Endocrine and bone complications in β-thalassemia intermedia: current understanding and treatment

Thalassemia intermedia (TI), also known as nontransfusion dependent thalassemia (NTDT), is a type of thalassemia where affected patients do not require lifelong regular transfusions for survival but may require occasional or even frequent transfusions in certain clinical settings and for defined periods of time. NTDT encompasses three distinct clinical forms: β-thalassemia intermedia (β-TI), Hb E/β-thalassemia, and α-thalassemia intermedia (Hb H disease). Over the past decade, our understanding of the molecular features, pathophysiology, and complications of NTDT particularly β-TI has increased tremendously but data on optimal treatment of disease and its various complications are still lacking. In this paper, we shall review a group of commonly encountered complications in β-TI, mainly endocrine and bone complications.

Selenium and Vitamin E as antioxidants in chronic hemolytic anemia: Are they deficient? A case-control study in a group of Egyptian children

Accelerated oxidative damage is one of the hallmarks in both sickle cell disease (SCD) and thalassemia major (TM). A decreased antioxidant level is found in both diseases. Our study was carried out to evaluate the variation in serum levels of Selenium and Vitamin E among a group of transfusion dependant Egyptian SCD and TM patients, further more to correlate these levels with iron overload status or transfusion requirements. A case-control study was conducted at the Cairo University Pediatric Hospital to assess the serum levels of Selenium using Atomic Absorption Spectrometer and Vitamin E using commercially available ELISA Kit in transfusion dependent children, 30 with beta thalassemia and 30 with SCD in a steady state aged from 6 to 18 years, these findings were compared to 30 age/sex matched healthy controls. Our results revealed a depleted antioxidants level in the studied group of Egyptian children with TM and SCD relative to healthy controls (P < 0.05). A significant positive correlation was found between Vitamin E levels and ferritin (r = 0.26, p = 0.047) in SCD and TM patients. Nonsignificant correlation was detected between serum Selenium and Vitamin E. Moreover, values of these antioxidants did not correlate with indices of hemolysis nor with those of inflammation in chronically transfused TM and SCD patients.

Thalassemia intermedia is associated with a proatherogenic biochemical phenotype

OBJECTIVE

Unlike beta thalassemia major (β-TM) in which cardiac siderosis represents the leading cause of mortality and morbidity, in beta thalassemia intermedia (β-TI), pulmonary hypertension (PHT) and thrombosis seems to be the major cardiovascular complications. However, the mechanism underlying these complications in β-TI is still unclear. Endothelial dysfunction, the key early event in atherogenesis, is now emerging as an important cardiovascular risk determiner in β-TI patients. Among the factors known to affect endothelial function, iron and cholesterol merit particular consideration in β-TI patients. Therefore, with the aim to extend our knowledge on the mechanisms connecting atherosclerosis to β-TI, in this study, we compared lipid and iron metabolism in serum and in peripheral blood mononuclear cells (PBMCs) from β-TI and β-TM patients and controls.

METHODS AND RESULTS

In this study the iron status and the lipid profile in serum and in peripheral blood mononuclear cells (PBMCs) of 22 adult β-TI patients were examined, and compared with 70 adult β-TM, and 50 age-matched controls. Despite the great variability, levels of serum iron and transferrin saturation were significantly higher in β-TI compared to both controls and β-TM. By contrast, transferrin and hepcidin levels were lower in β-TI patients. Changes in serum indicators in β-TI patients were associated with altered expressions in PBMCs of hepcidin and IL-1α, involved in some way in the regulation of iron homeostasis. In addition β-TI exhibited a reduction of total and high density lipoprotein cholesterol in serum and of neutral cholesterol ester hydrolase in PBMCs, and an increase of cytoplasmic neutral lipids and mRNA levels of acetyl-coenzymeA:cholesterol acyltransferase.

CONCLUSIONS

Taken together, these findings provide experimental support for the idea that β-TI patients exhibit a proatherogenic biochemical phenotype which may contribute to enhance cardiovascular risk in these subjects.

Plasma lipids and lipoproteins in children and young adults with major β-thalassemia from western Iran: influence of genotype

To determine the plasma lipid and lipoprotein profiles and their possible association with the type of β-thalassemia mutation we studied 103 major β-thalassemia patients including 71 children and 32 young adults compared to 102 healthy subjects consisted of 90 children and 12 young healthy adults. The plasma lipid and lipoprotein levels were measured by conventional methods. Considering all of the patients the levels of total cholesterol (TC), LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C) were significantly lower compared to controls. However, the level of TG was significantly higher in cases than controls. Comparing thalassemic patients homozygous for a β0 type of mutation with those homozygous for a β+ type of mutation (IVSI.110 G:A) indicated that the levels of LDL-C, TC were significantly increased and TG concentration tended to be higher in the latter patients. In conclusion, our study indicates that hemolytic stress results in hypocholesterolemia in major β-thalassemia patients and the presence of more severe genotype in patients is correlated with more reduction in TG, TC, and LDL-C levels.

Hemoglobin H-constant spring in North America: an alpha thalassemia with frequent complications

Hemoglobin H-constant spring (Hb H-CS), the most common nondeletional alpha thalassemia in Asia is increasingly recognized in North America due to shifts in immigration patterns. In California, alpha (α)-thalassemia syndromes are the second most frequent finding among newborns screened for hemoglobinopathies with a two-fold increase compared to a decade earlier [1 ,2 ]. Though known to have a more severe anemia than Hb H disease, the other clinical findings of Hb H-CS are not well described. Moreover, beneficial therapies that have become available in the last decade are often not applied to their care. This analysis of 46 patients enrolled in the Thalassemia Clinical Research Network (TCRN) age 13+/− 10 years old, with Hb H-CS revealed moderate anemia (mean 8.7 ± 1.5 g/dl), regular transfusion therapy in 24% of patients, and splenomegaly or prior splenectomy in one-third of them. Serum transferin receptor (sTfr), was elevated; (44.4 ± 18 mcg/ml normal range 2.9–8.3 mcg/ml), reflecting ineffective erythropoiesis, which in turn leads to high iron absorption and increased ferritin levels in younger (median = 187 ng/ml) and older (median = 465 ng/ml) nontransfused patients. These findings along with moderate growth delay and low bone mass were more prevalent in Hb H-CS patients compared to deletional Hb H disease. Our results highlight the required monitoring of the extent of anemia, growth, splenomegaly, iron overload, gallstones, bone density and assessment of need for transfusions and specific treatments for disease complications.