Myocardial iron overload in thalassaemia major. How early to check?

The age at which it is necessary to start Cardiovascular Magnetic Resonance (CMR) T2* screening in thalassaemia major (TM) is still uncertain. To clarify this point, we evaluated the prevalence of myocardial iron overload (MIO), function and fibrosis by CMR in TM patients younger than 10 years. We retrospectively selected 35 TM patients enrolled in the Myocardial Iron Overload in Thalassaemia network. MIO was measured by T2* multislice multiecho technique. Biventricular function parameters were evaluated by cine images. To detect myocardial fibrosis, late gadolinium enhancement images were acquired. Patients' age ranged from 4·2 to 9·7 years. All scans were performed without sedation. Nine patients showed no MIO, 22 patients had heterogeneous MIO with a T2* global value ≥20 ms; two patients had heterogeneous MIO with a T2* global value <20 ms and two patients showed homogeneous MIO. No patient showed myocardial fibrosis. Among the patients with heart T2*<20 ms, the youngest was 6 years old, none showed heart dysfunction and the iron transfused was <35 g in all cases. Cardiac iron loading can occur much earlier than previously described. The first cardiac T2* assessment should be performed as early as feasible without sedation, especially if chelation is started late or if poor compliance is suspected.

Cardiac complications and diabetes in thalassaemia major: a large historical multicentre study.

The relationship between diabetes mellitus (DM) and cardiac complications has never been systematically studied in thalassaemia major (TM). We evaluated a large retrospective historical cohort of TM to determine whether DM is associated with a higher risk of heart complications. We compared 86 TM patients affected by DM with 709 TM patients without DM consecutively included in the Myocardial Iron Overload in Thalassaemia database where clinical/instrumental data are recorded from birth to the first cardiovascular magnetic resonance (CMR) exam. All of the cardiac events considered were developed after the DM diagnosis. In DM patients versus non-DM patients we found a significantly higher frequency of cardiac complications (46.5% vs. 16.9%, P < 0.0001), heart failure (HF) (30.2% vs. 11.7%, P < 0.0001), hyperkinetic arrhythmias (18.6% vs. 5.5%, P < 0.0001) and myocardial fibrosis assessed by late gadolinium enhancement (29.9% vs. 18.4%, P = 0.008). TM patients with DM had a significantly higher risk of cardiac complications [odds ratio (OR) 2.84, P < 0.0001], HF (OR 2.32, P = 0.003), hyperkinetic arrhythmias (OR 2.21, P = 0.023) and myocardial fibrosis (OR 1.91, P = 0.021), also adjusting for the absence of myocardial iron overload assessed by T2* CMR and for the covariates (age and/or endocrine co-morbidity). In conclusion, DM significantly increases the risk for cardiac complications, HF, hyperkinetic arrhythmias and myocardial fibrosis in TM patients.

Cardiac and hepatic iron and ejection fraction in thalassemia major: multicentre prospective comparison of combined deferiprone and deferoxamine therapy against deferiprone or deferoxamine monotherapy.

BACKGROUND: Due to the limited data available in literature, the aim of this multi-centre study was to prospectively compare in thalassemia major (TM) patients the efficacy of combined deferiprone (DFP) and deferoxamine (DFO) regimen versus either DFP and DFO in monotherapy by cardiovascular magnetic resonance (CMR) over a follow up of 18 months. METHODS: Among the first 1135 TM patients in the MIOT (Myocardial Iron Overload in Thalassemia) network, we evaluated those who had received either combined regimen (DFO + DFP, N=51) or DFP (N=39) and DFO (N=74) monotherapies between the two CMR scans. Iron overload was measured by T2* multiecho technique. Biventricular function parameters were quantitatively evaluated by cine images. RESULTS: The percentage of patients that maintained a normal global heart T2* value was comparable between DFP+DFO versus both monotherapy groups. Among the patients with myocardial iron overload at baseline, the changes in the global heart T2* and in biventricular function were not significantly different in DFP+DFO compared with the DFP group. The improvement in the global heart T2* was significantly higher in the DFP+DFO than the DFO group, without a difference in biventricular function. Among the patients with hepatic iron at baseline, the decrease in liver iron concentration values was significantly higher with combination therapy than with either monotherapy group. CONCLUSIONS: In TM patients at the dosages used in the real world, the combined DFP+DFO regimen was more effective in removing cardiac iron than DFO, and was superior in clearing hepatic iron than either DFO or DFP monotherapy. Combined therapy did not show an additional effect on heart function over DFP.

Multi-potent progenitors in freshly isolated and cultured human mesenchymal stem cells: a comparison between adipose and dermal tissue.

Mesenchymal stem cells (MSCs) from human adult adipose tissue (A-MSCs) have a better differentiative ability than MSCs derived from the derma (D-MSCs). To test whether this difference is associated with differences in the content of multi-potent progenitors in A-MSCs, the number and the differentiative properties of multi-potent progenitors have been analyzed in various preparations of A-MSCs and D-MSCs. Adipogenic and osteogenic differentiation performed on colony-forming units have revealed that adipogenic and osteogenic progenitors are similar in the two populations, with only a slighty better performance of A-MSCs over D-MSCs from passages p0 to p15. An analysis of the presence of tri-, bi-, uni- and nulli-potent progenitors isolated immediately after isolation from tissues (p0) has shown comparable numbers of tri-potent and bi-potent progenitors in MSCs from the two tissues, whereas a higher content in uni-potent cells committed to adipocytes and a lower content in nulli-potent cells has been observed in A-MSCs. Furthermore, we have characterized the progenitors present in A-MSCs after six passages in vitro to verify the way in which in vitro culture can affect content in progenitor cells. We have observed that the percentage of tri-potent cells in A-MSCs at p6 remains similar to that observed at p0, although bi-potent and uni-potent progenitors committed to osteogenic differentiation increase at p6, whereas nulli-potent cells decrease at p6. These data indicate that the greater differentiative ability of A-MSC populations does not correlate directly with the number of multi-potent progenitors, suggesting that other factors influence the differentiation of bulk populations of A-MSCs.

Effects of two organotin(IV)(sulfonatophenyl)porphinates on MAPKs and on the growth of A375 human melanoma cells.

Previously we showed apoptotic induction in A375 human melanoma cells using two complexes of the meso-tetra(4-sulfonatophenyl)porphinate (TPPS), (Bu2Sn)2TPPS and (Bu3Sn)4TPPS. To understand how these compounds activate apoptosis in melanoma cells we studied MAPKs and the (Bu2Sn)2TPPS and (Bu3Sn)4TPPS cellular uptake. Western blotting experiments showed activated protein kinases ERK 1/2, JNK and p38 in 10 microM (Bu2Sn)2TPPS- and 1 microM (Bu3Sn)4TPPS-treated melanoma cells, which suggests that the three MAP kinases are involved in the apoptotic death of A375-treated cells. By taking advantage of the porphyrin fluorescence, we found a fast concentration of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS in the nucleus and in the nucleoli compared to TPPS. A significantly reduced growth of A375 human melanoma cells was also observed after only 48 h treatment by using 500 nM of (Bu2Sn)2TPPS or 80 nM of (Bu3Sn)4TPPS. A strong slowdown of cell growth and loss of cell-cell interactions were visible by in vitro wound repair assay.