Normality ranges of urine oxidative stress markers (8-OHdG and isoprostane) in Italian people free from respiratory diseases-Preliminary results

BACKGROUND: The study of oxidative stress (OxS) is becoming increasingly important in respiratory disease research. To our knowledge, the reference ranges of urinary 8-hydroxy-deoxy-guanosine (8-OHdG) and 8-isoprostane (isoprostane), a DNA and a lipid oxidation product respectively, have not yet been determined in subjects without respiratory diseases. AIM: To assess the reference range of OxS markers in Italian people aged 20-64 free from respiratory diseases (controls). METHODS: 8-OHdG and isoprostane were measured in spot-urine samples collected in the frame of Gene-Environment Interactions in Respiratory Diseases (GEIRD) study, a nested multi-case control survey. The biomarkers levels were corrected on creatinine concentration. Only controls (n=239) were considered for the aim of this work. The possible effects of potential determinants on OxS-biomarkers were studied before determining the normality range in selected subgroups of controls. Multiple linear regression was fitted to data using the logarithm of 8OHdG or isoprostane as dependent variables and sex, age, season, smoke, body mass index, as covariates. The appropriate percentiles were calculated. RESULTS: Both 8OHdG and isoprostane concentrations were significantly higher in smokers than in non smokers (p=0.025 and 0.047 respectively), while the other covariates did not influence OxS. The 95% 8OHdG normality range in non smokers varied from 0.26 to 25.94 ng/mg. The 95% isoprostane reference interval was 0.03 -5.42 ng/mg in non smokers. CONCLUSION: Provisional 95% normality range for urinary 8OHdG and isoprostane were determined in subjects free from respiratory diseases

Measurement of a urinary marker (8-hydroxydeoxy-guanosine, 8-OHdG) of DNA oxidative stress in epidemiological surveys: a pilot study

Background: 8-Hydroxydeoxyguanosine (8-OHdG) is a commonly used marker of DNA oxidative stress in epidemiological studies. The aim of this study was to establish whether the urinary concentration of 8-OHdG varies during the first part of the day, when clinical tests are usually performed, and whether it can therefore be measured without bias in spot urine samples. Material and methods: Spot urine samples were collected using a convenience sample. A linear mixed-effects model for repeated measurements was used to analyze 8-OHdG levels. Results: A significant increasing trend in time in the 8-OHdG concentration was found among smokers, but not in the case of nonsmokers. Conclusions: In epidemiological studies on oxidative stress, all participants should collect their early morning urine specimens – before their first cigarette if they are smokers – to gather information on individual background oxidation levels

Interspecies somatic T cell hybrids as biological tools for studying gene expression during T cell development.

Interspecies somatic cell hybrids were generated by fusing the mouse thymic lymphoma cell line, BW5147, with normal human T lymphocytes at different stages of differentiation. Thymocytes, activated peripheral T lymphocytes, or an activated T cell clone were used as human partners, respectively, in three independent fusions. Phenotype and genetic analysis demonstrated that these hybrids preferentially segregated human chromosomes while retaining a complete mouse genetic complement, irrespective of the human partner used for fusion. A large number of T cell differentiation antigens constitutively expressed throughout the T lymphocyte development remained consitutively expressed in the hybrids, irrespective of the maturation stage of human partner used for fusion. In contrast, the expression of other antigens related to a specific stage of T cell development (CD2, CD8), or to an activated state of T lymphocytes (HLA-DR, CD25), was to observed in the hybrids, with no apparent correlation with the segregation of human chromosomes other than, of course, the encoding chromosome. From these results we suggest that the developmental stage of the fusion partners strongly influences the pattern of expression by activating or silencing genes programmed to be expressed in distinct phases of T cell ontogeny

BIOMARKERS OF OXIDATIVE STRESS IN CHRONIC RESPIRATORY DISEASES.

It is known that, during oxidative stress process, reactive oxygen species (ROS) suppress antioxidant capacity in vivo. As a result, DNA, lipids, and proteins get damaged [1, 2]. Last investigations show that some respiratory diseases are associated with DNA- and lipid-derived oxidative stress [3, 4]. By this reason the study of oxidative stress (OxS) is becoming increasingly important in respiratory disease research. An elevated level of oxidative stress may be associated with development of asthma, chronic bronchitis or airway obstruction

Divergent evolution in the mechanisms controlling MHC class II gene transcription in mouse and human.

The expression of the major histocompatibility complex (MHC) class II gene family is developmentally regulated and, in generaI, in a coordinate manner. In this study, we show that the expression of the entire repertoire of human class II genes, otherwise transcriptionally silent in the bare Iymphocyte syndrome derived BLSI celI line, can be rescued by somatic celI hybridization with normal mouse spleen celIs. The analysis of the interspecies celI hybrids revealed a particularly important and unprecedented aspect. A return to the BLSI-like, human MHC class Il-negative phenotype due to segregation of mouse chromosomes was accompanied in certain hybrids by loss of lE, but not lA cell surface antigen expression. At the molecular level, this was the result of lack of Ea-specific mRNA in the presence of E beta-, A alpha- and A beta- specific mRNA. Thus, the mouse trans-acting function operating across species barriers and able to complement the defect of human BLSI cells diverged in mice to control Ea, but not Eb, Aa and Ab gene expression. These findings suggest that evolutionary pressure has maintained the expression of the MHC class II multigene family under the control of quite distinct species-specific transcriptionai mechanisms

Lack of association of metastasis-associated lung adenocarcinoma transcript 1 variants with melanoma skin cancer risk

The long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been implicated in melanoma. Polymorphisms in MALAT1 may play a vital role in the progress of melanoma by its regulative function. However, potential genetic variants in MALAT1 affecting the risk of melanoma onset have not been explored. In this study, two single nucleotide polymorphisms (rs3200401 and rs619586) in MALAT1 were selected for genotyping of 334 melanoma patients and 291 cancer-free controls in an Italian population. The results showed that MALAT1 rs3200401 and rs619586 were not associated with melanoma risk. A further breakdown analysis by sex stratification also indicated a lack of association between these polymorphisms and melanoma. In addition, we tested 450\u2009bp of the proximal 5' flanking region of the gene for the presence of polymorphisms that could be associated with melanoma risk and found no variants in 96 melanoma patients. In conclusion, our results suggest that there is no contribution of MALAT1 rs3200401 and rs619586 polymorphisms or polymorphisms in the core promoter that could be associated with the risk of melanoma skin cancer in this specific study setting. Further validation will be required in larger studies involving different settings/larger populations in order to reach conclusive results

Ruolo dell’infezione da poliomavirus nel cancro del colon in un’area del Nord Est d’Italia

OBIETTIVI: I poliomavirus JCV, BKV, SV40 e Merkel Cell Poliomavirus (MCPy) sono virus oncogeni con un’elevata omologia strutturale e di sequenza. Mentre i poliomavirus BKV/JCV e Merkel sono definiti virus umani e ubiquitari, SV40 è un virus delle scimmie introdotto nel contesto umano attraverso la somministrazione accidentale del vaccino antipoliomielitico contaminato. Le modalità di trasmissione inter-umana non sono ancora ben definite sebbene la presenza virale nelle tonsille e nel tratto gastro-intestinale depongono sia per una trasmissione per via respiratoria che oro-fecale. Dal punto di vista della patomorfosi, sono stati associati a specifici istiotipi tumorali quali osteosarcomi, mesoteliomi, linfomi, tumori cerebrali e della pelle. Attualmente, sono disponibili dati contrastanti circa il ruolo causale di questi virus nel cancro del colon-retto (CRC). Obiettivo del presente studio è individuare il ruolo dell’infezione da poliomavirus nella genesi del cancro del colon retto attraverso uno studio caso-controllo molecolare. MATERIALI: 64 campioni di tumore, (età media 69.9±11.0 anni; 40 maschi) e 80 campioni provenienti dal gruppo di controllo costituito da familiari conviventi (età media 53.7±8.6 anni; 43 uomini; 55 figli/figlie, 23 fratelli/sorelle, e 2 parenti) sono stati analizzati con Rt-qPCR e sequenziamento per regioni specifiche dell’AgT caratterizzanti ciascun genoma virale. RIASSUNTO: SV40 è stato rilevato, con bassa carica virale, in 6adenocarcinomi (6.4%) (OR=3.91; p=0.115) mentre MCPyV è stato identificato nel 6.3% dei 64 pazienti con tumore e nell’8.8% dei controlli. Inquesto gruppo, il 12.5% dei campioni positivi erano classificati come adenoma/polipo. Anche in questo caso non è stata osservata nessunaassociazione statisticamente significativa tra le lesioni precancerose e il tessuto normale. Non è stata invece evidenziata nessuna infezione daJCV/BKV. CONCLUSIONI: Sebbene in questo studio è stata dimostrata la presenzadi SV40 e di MCPyV in tumori del colon retto e in lesione precancerose, l’ipotesi di una relazione etiopatogenetica non è sostenuta da significativitàstatistica in relazione al gruppo di controllo. Questi dati suggeriscono che l’infezione del tratto gastroenterico è dovuta alla trasmissione di tipo feco-orale e che il supposto ruolo dei poliomavirus nella genesi di questo tumore dovrebbe essere ridiscusso

Natural pollen exposure increases in a dose-dependent way Fraction of exhaled Nitric Oxide (FeNO) levels in patients sensitized to one or more pollen species

Background: Co-exposures and polysensitization to several pollen species are very common in real life practice. However, little information exists on allergic symptoms and airway inflammation related to natural pollen exposure in large general population samples. Objective: To assess the combined effect of sensitization and/or exposure to one or more pollen species on Fraction of exhaled Nitric Oxide (FeNO) levels. Methods: Within Gene Environment Interactions in Respiratory Diseases (GEIRD) multicase-control study, 1070 adults from the general population of Verona, Italy, underwent a clinical evaluation including standardized interview, spirometry, skin prick test to inhalants and FeNO measurement. Pollen exposure was assumed, when the mean pollen concentration in the previous week was above the cutoff established by the Italian Aerobiological Monitoring Network. Results: Subjects sensitized to one or more pollen species were respectively 15.5% and 29.6%. FeNO levels were directly related to the number of both pollen species around and pollen-related sensitizations. Median FeNO levels were directly related to number of pollen species around and pollen sensitization. FeNO levels increased from 15.4 ppb (p. 25-p. 75 = 9.9-21.0) outside the pollen season to 17.5 ppb (11.2-30.5) when there were ≥3 pollen species around. Likewise FeNO levels rose from 14.8 ppb (10.0-22.3) in not sensitized subjects, to 16.7 (10.1-25.0) in monosensitized and further to 20.4 (12.3-40.6) in poly-sensitized. According to multivariable quantile regression, median FeNO was 17.9 ppb higher (p. 25-p. 75 = 12.5-23.3) for subjects sensitized and exposed to more than one pollen species, compared to subjects who were neither sensitized nor exposed. Differences in FEV1/FVC between groups were less pronounced (-2.0%, -4.1 to 0.1). Median FeNO level was 15.1 ppb (p. 25-p. 75 = 10.0-23.2) in subjects without pollen-related symptoms, 17.8 ppb (12.1-40.2) in those with nasal symptoms only, and 22.7 ppb (14.7-43.0) in those with asthma-like symptoms (p < 0.001). Conclusion and clinical relevance: Airways inflammation, evaluated by FeNO, increases in dose-dependent manner from subjects monosensitized to pollen species to those poly-sensitized, especially when asthma-like symptoms on pollen exposure are also reported. This should be considered by allergists during natural pollen seasons when evaluating both pulmonary function and airways inflammation