Correlation of 99mTc-DPD bone scintigraphy with histological amyloid load in patients with ATTR cardiac amyloidosis.

BACKGROUND: The significance of measuring 99mTc-labelled-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) in transthyretin (ATTR) cardiac amyloidosis has not been adequately studied. This single-centre observational study evaluated the correlation between 99mTc-DPD scintigraphy and histological amyloid load in endomyocardial biopsy (EMB). METHODS: Twenty-eight patients with biopsy-proven ATTR amyloidosis and concomitantly available 99mTc-DPD scintigraphy were included. Visual Perugini scoring, and (semi-)quantitative analysis of cardiac 99mTc-DPD uptake by planar whole-body imaging and single photon emission computed tomography (SPECT/CT) using regions of interest (ROI) were performed. From this, heart-to-whole-body ratio (H/WB) and heart-to-contralateral-chest ratio (H/CL) were calculated. The histological amyloid load was quantified using two different staining methods. RESULTS: Increased cardiac tracer uptake was documented in all patients (planar: ROImean 129 ± 37 cps; SPECT/CT: ROImean 369 ± 142 cps). Histological amyloid load (19 ± 13%) significantly correlated with Perugini score (r = 0.69, p < .001) as well as with cardiac 99mTc-DPD uptake (planar: r = 0.64, p < .001; H/WB: r = 0.50, p = .014; SPECT/CT: r = 0.53, p = .008; H/CL: r = 0.43, p = .037) (results are shown for correlations with Congo Red-staining). CONCLUSION: In ATTR, cardiac 99mTc-DPD uptake significantly correlated with histological amyloid load in EMB. Further studies are needed to implement thresholds in cardiac 99mTc-DPD uptake measurements for risk stratification and guidance of therapy.

Countervailing effects of rapamycin (sirolimus) on nuclear factor-kappa B activities in neointimal and medial smooth muscle cells.

OBJECTIVE: Local application of rapamycin (sirolimus) by drug-eluting stents prevents lumen obliteration after angioplasty by inhibition of neointimal hyperplasia. The effects of rapamycin on neointimal smooth muscle cells (niSMC) which are responsible for the occurrence of restenosis have not been investigated so far. METHODS AND RESULTS: Rat niSMC and medial SMC (mSMC) were obtained from balloon catheter-injured arteries. The niSMC exhibited higher basal NF-kappaB activity and TNF-alpha mRNA levels. Nuclear protein binding to NF-kappaB-DNA was attenuated in niSMC by incubation with rapamycin (0.1 and 1 microg/ml) for 24 and 48 h. In contrast in mSMC, 0.1 microg/ml rapamycin had no effect and at 1 microg/ml even increased nuclear protein binding to NF-kappaB-DNA. After 12 h incubation, rapamycin (0.001-10 microg/ml) induced IkappaB-alpha protein in niSMC, whereas in mSMC it stimulated IkappaB-alpha at much lower levels. Prolonged rapamycin treatment (1 microg/ml for 72 h) had no effect on TNF-alpha mRNA level and NF-kappaB activity in niSMC, whereas it led to their increase in mSMC. Vascular endothelial growth factor (VEGF) secretion was higher in mSMC than in niSMC; rapamycin decreased VEGF levels in both cell types. Ultrastructural analysis suggested that rapamycin caused early signs of degeneration in niSMC, but enhanced protein synthesis in mSMC. CONCLUSIONS: This study shows that rapamycin influences the inflammatory phenotypes of SMC in opposite directions: it reduces the high basal NF-kappaB activity in niSMC and enhances NF-kappaB activity and TNF-alpha expression in mSMC. In addition, rapamycin inhibits VEGF production regardless of the phenotype of SMC. These findings shed light on molecular mechanisms and structural changes underlying therapeutic applications of rapamycin in prevention of restenosis, inhibition of chronic transplant arteriosclerosis and reduction of secondary malignoma formation due to immunosuppression.

Effect of atorvastatin on circulating proinflammatory T-lymphocyte subsets and soluble CD40 ligand in patients with stable coronary artery disease--a randomized, placebo-controlled study.

BACKGROUND: Coronary atherosclerosis includes an activation of circulating T lymphocytes. Statins exert anti-inflammatory effects beyond lipid lowering. Whether these properties influence systemic T lymphocytes is unclear. METHODS: To investigate the effect of atorvastatin on circulating T-lymphocyte subsets producing proinflammatory and anti-inflammatory cytokines (interferon gamma [IFN-gamma(+)], interleukin 2 [IL-2(+)], IL-4(+), and IL-10(+)) and on the T-cell-activating soluble CD40 ligand (sCD40L), 30 hypercholesterolemic patients with angiographically documented stable coronary artery disease (CAD) were randomized to placebo or atorvastatin (20 mg/d) for 3 months. Eight healthy volunteers served as controls. Levels of peripheral cytokine-producing CD4+ and CD8+ T cells and their CD28- subsets were determined by FACS. Serum soluble CD40L was measured with ELISA. RESULTS: IL-2(+) T lymphocytes and sCD40L levels were higher in patients with CAD compared with controls, whereas IFN-gamma(+) and anti-inflammatory IL-4(+) and IL-10(+) T lymphocytes were similar. Levels of IL-2(+), IFN-gamma(+), IL-4(+), and IL-10(+) T-cell subsets as well as CD28- T lymphocytes were neither changed by atorvastatin nor by placebo, whereas sCD40L was lowered only in atorvastatin-treated patients (P < .01). CONCLUSION: Circulating IL-2(+) T lymphocytes are increased in patients with stable CAD reflecting an activation of the global immune system, but are not influenced by atorvastatin therapy. The elevated levels of platelet-derived T-lymphocyte-stimulating sCD40L are decreased by atorvastatin probably reflecting an atheroprotective effect. Hence, sCD40L may be an additional biomarker to be considered when evaluating the treatment effects of statins in patients with stable CAD.