Telomere length elongation after weight loss intervention in obese adults.

INTRODUCTION: Telomeres may be considered markers of biological aging, shorter telomere length is associated with some age-related diseases; in several studies short telomere length has also been associated to obesity in adults and adolescents. However the relationship between telomere complex functions and obesity is still not clear. Aim of the study was to assess telomere length (TL) in adults' obese subjects before and after weight loss obtained by placement of bioenteric intragastric balloon (BIB) for 6months. METHODS: We enrolled 42 obese subjects before and after BIB placement as weight loss intervention. Blood samples were collected in order to obtain DNA from leukocyte to measure TL by quantitative PCR. RESULTS: Data were analyzed only in 37 subjects with complete data; all presented important body weight loss (124.06±26.7 vs 105.40±23.14, p<0.001) and more interesting they presented a significant increase in TL (3.58±0.83 vs 5.61±3.29, p<0.001). Moreover we observed a significant positive correlation between TL elongation and weight loss (r=0.44, p=0.007) as well as an inverse correlation between TL at baseline and TL elongation (r=-0.35, p=0.03).The predictors of TL elongation were once again weight loss and short TL at baseline (respectively p=0.007 and p=0.003). CONCLUSIONS: Our study shows that weight loss is associated to telomere lengthening in a positive correlation: the greater weight loss the greater telomere lengthening; moreover telomere lengthening is more significant in those subjects with shortest telomeres at baseline.

Increased appearance rate of 27-hydroxycholesterol in vivo in hypercholesterolemia: a possible compensatory mechanism.

BACKGROUND AND AIMS: The first step in the alternative pathway of bile acid biosynthesis is the 27-hydroxylation of cholesterol, which takes place both in liver and extrahepatic tissues. This pathway is believed to play a role in peripheral cholesterol degradation. Aim of this study was to investigate the impact of hyperlipidemia on 27-hydroxycholesterol appearance rate, and to assess the effects induced by treatment with statins. METHODS AND RESULTS: Seven patients with familial hypercholesterolemia and eight patients with familial combined hyperlipidemia underwent determination of 27-hydroxylation rates in vivo by i.v. infusion of deuterated 27-hydroxycholesterol. Isotope enrichment was assayed by gas chromatography-mass spectrometry, allowing to calculate 27-hydroxycholesterol appearance rates. Six normocholesterolemic subjects were regarded as controls. In some hypercholesterolemic patients the infusions were repeated during treatment with atorvastatin or rosuvastatin. Hydroxylation rates were higher in hypercholesterolemic patients (8.7 ± 2.5 mg/h; controls, 3.4 ± 2.0 mg/h; combined hyperlipidemia, 4.4 ± 1.6 mg/h; mean ± SD, P < 0.01 vs both). After statin treatment, both plasma cholesterol levels and hydroxylation rates dropped by nearly 50%. No difference was detectable between the two statins. A linear correlation was shown between plasma cholesterol and 27-hydroxylation rates. CONCLUSION: Hypercholesterolemia associates with increased 27-hydroxycholesterol appearance rates, which decrease during hypocholesterolemic treatment. The correlation with cholesterol levels supports the view that 27-hydroxylation may act as a compensatory mechanism in a condition of larger plasma cholesterol pool. A regulatory role for hepatic and extrahepatic nuclear receptors seems reasonable. These data prompt novel pharmacological approaches for the management of hypercholesterolemia and the prevention of atherosclerosis.

Concomitant high gene copy number and protein overexpression of IGF1R and EGFR negatively affect disease-free survival of surgically resected non-small-cell-lung cancer patients.

BACKGROUND: Insulin-like growth factor 1 receptor (IGF1R) represents a novel molecular target in non-small-cell-lung cancer (NSCLC). IGF1R and epidermal growth factor receptor (EGFR) activation are essential to mediate tumor cell survival, proliferation, and invasion. This study investigates the prognostic role of IGF1R and EGFR in surgically resected NSCLC. MATERIALS AND METHODS: IGF1R and EGFR copy number gain (CNG) were tested by fluorescence in situ hybridization (FISH) and protein expression by immunohistochemistry (IHC) in 125 stage I-II-IIIA NSCLC patients. RESULTS: Fourty-six tumors (40.3%) were IGF1R FISH-positive (FISH+), and 76 (67.2%) were EGFR FISH+. Tumors with concomitant IGF1R/EGFR FISH+ were observed in 34 cases (30.1%). IGF1R and EGFR FISH+ were associated with SCC histology (p = 0.01 and p = 0.04, respectively). IGF1R and EGFR protein over-expression (IHC+) were detected in 45 (36.0%) and 69 (55.2%) cases, respectively. Tumors with concomitant IGF1R/EGFR IHC+ were detected in 31 (24.8%) patients. IGF1R/EGFR FISH+ and IGF1R/EGFR IHC+ were significantly associated (χ(2) = 4.02, p = 0.04). Patients with IGF1R/EGFR FISH+ and IGF1R/EGFR IHC+ were associated with shorter disease-free survival (DFS) (p = 0.05 and p = 0.05, respectively). Patients with concomitant IGF1R/EGFR FISH+/IHC+ had a worse DFS and overall survival (p = 0.005 and p = 0.01, respectively). The multivariate model confirmed that IGF1R/EGFR FISH+/IHC+ (hazard ratio (HR), 4.08; p = 0.01) and tumor stage (II-III vs I) (HR, 4.77; p = 0.003) were significantly associated with worse DFS. CONCLUSIONS: IGF1R/EGFR FISH+ correlates with IGF1R/EGFR IHC+. IGF1R/EGFR FISH+/IHC+ is an independent negative prognostic factor for DFS in early NSCLC. These features may have important implications for future anti-IGF1R therapeutic approaches.

Optimization of patient selection for EGFR-TKIs in advanced non-small cell lung cancer by combined analysis of KRAS, PIK3CA, MET, and non-sensitizing EGFR mutations.

BACKGROUND: We present a comprehensive analysis of KRAS, PIK3CA, MET, and non-sensitizing EGFR mutations in advanced non-small cell lung cancer (NSCLC) patients treated with tyrosine kinase inhibitors (TKIs), with the aim of clarifying the relative contribution of these molecular alterations to resistance. PATIENTS AND METHODS: One hundred and sixty-six patients with advanced NSCLC treated with EGFR-TKIs with available archival tissue specimens were included. EGFR (exons 18-21), KRAS (exons 2, 3), PIK3CA (exons 9, 20), and MET (exons 14, 15) mutations were analyzed using PCR-based sequencing. Among all the mutations evaluated, only KRAS, PIK3CA, MET, and non-sensitizing EGFR mutations, defined as "TKI non-sensitizing mutations" were used for response, time to progression (TTP), and overall survival (OS) analysis. RESULTS: TKI non-sensitizing mutations were associated with disease progression (p = 0.001), shorter TTP (p < 0.0001), and worse OS (p = 0.03). Cox's multivariate analysis including histology and performance status showed that TKI non-sensitizing mutations were independent factors for shorter TTP (p < 0.0001) and worse OS (p = 0.01). CONCLUSIONS: When KRAS, PIK3CA, MET, and non-sensitizing EGFR mutations are concomitant, up to 96.0% of NSCLC patients unlikely to respond to TKIs can be identified, and they represented independent negative prognostic factors. Comprehensive molecular dissection of EGFR signaling pathways should be considered to select advanced NSCLC patients for TKIs therapies.

Are maternal mitochondria the selfish entities that are masters of the cells of eukaryotic multicellular organisms?

The Energide concept, as well as the endosymbiotic theory of eukaryotic cell organization and evolution, proposes that present-day cells of eukaryotic organisms are mosaics of specialized and cooperating units, or organelles. Some of these units were originally free-living prokaryotes, which were engulfed during evolutionary time. Mitochondria represent one of these types of previously independent organisms, the Energide, is another type. This new perspective on the organization of the cell has been further expanded to reveal the concept of a public milieu, the cytosol, in which Energides and mitochondria live, each with their own private internal milieu. The present paper discusses how the endosymbiotic theory implicates a new hypothesis about the hierarchical and communicational organization of the integrated prokaryotic components of the eukaryotic cell and provides a new angle from which to consider the theory of evolution and its bearing upon cellular complexity. Thus, it is proposed that the "selfish gene" hypothesis of Dawkins1 is not the only possible perspective for comprehending genomic and cellular evolution. Our proposal is that maternal mitochondria are the selfish "master" entities of the eukaryotic cell with respect not only to their propagation from cell-to-cell and from generation-to-generation but also to their regulation of all other cellular functions. However, it should be recognized that the concept of "master" and "servant" cell components is a metaphor; in present-day living organisms their organellar components are considered to be interdependent and inseparable.

On the key role played by altered protein conformation in Parkinson's disease.

On the basis of the previously proposed hierarchic organisation of the central nervous system (CNS) and of its syntropic behaviour, a view of neurodegenerative diseases focusing on the assemblage of abnormal multimeric proteins (pathologic protein mosaics (PMs)) is proposed. Thus, the main focus of the present paper is on Parkinson's disease (PD) as a neurodegenerative disease, which has as crucial feature protein conformational alterations and formation of pathological PMs. Two interconnected cellular dysfunctions are discussed as main pathogenic factors of PD syndromes, namely mitochondrial deficits (i.e. energy failure, especially critical for Substantia Nigra DA neurons) and conformational protein alterations (due to genetic or environmental causes). Conformational protein alterations can trigger pathological phenomena via the loss and/or the gain of new functions. In particular, altered proteins can lead to the formation of abnormal PMs, which can, inter alia, cause distortion of cellular structures, toxic functions and/or formation of improper membrane ion channels. In view of the fact that disordered proteins can easily acquire unwanted conformation, the "disorder index" (DI) for proteins involved in PD has been evaluated. It has been found that both alpha-synuclein and tau-protein have high DI. This datum is in agreement with the observation that these two proteins synergistically promote polymerisation of each other into amyloid fibrils, favouring the formation of Lewy bodies.