Oxidative and DNA damage in obese patients undergoing bariatric surgery: A one-year follow-up study.

The pathogenesis of obesity and related comorbidities has long been associated with oxidative stress. The excess of adipose tissue contributes to the production of free radicals that sustain both a local and a systemic chronic inflammatory state, whereas its reduction can bring to an improvement in inflammation and oxidative stress. In our work, using the fluorescent lipid probe BODIPY® 581/591 C11 and the γH2AX foci assay, a well-known marker of DNA double strand breaks (DSB), we evaluated the extent of cell membrane oxidation and DNA damage in peripheral blood lymphocytes of normal weight (NW) controls and obese patients sampled before and after bariatric surgery. Compared to NW controls, we observed a marked increase in both the frequencies of oxidized cells or nuclei exhibiting phosphorylation of histone H2AX in preoperatory obese patients. After bariatric surgery, obese patients, resampled over one-year follow-up, improved oxidative damage and reduced the presence of DSB. In conclusion, the present study highlights the importance for obese patients undergoing bariatric surgery to also monitor these molecular markers during their postoperative follow-up.

IL-10 Overexpression After BCG Vaccination Does Not Impair Control of Mycobacterium tuberculosis Infection.

Control of tuberculosis depends on the rapid expression of protective CD4+ T-cell responses in the Mycobacterium tuberculosis (Mtb)-infected lungs. We have recently shown that the immunomodulatory cytokine IL-10 acts intrinsically in CD4+ T cells and impairs their parenchymal migratory capacity, thereby preventing control of Mtb infection. Herein, we show that IL-10 overexpression does not impact the protection conferred by the established memory CD4+ T-cell response, as BCG-vaccinated mice overexpressing IL-10 only during Mtb infection display an accelerated, BCG-induced, Ag85b-specific CD4+ T-cell response and control Mtb infection. However, IL-10 inhibits the migration of recently activated ESAT-6-specific CD4+ T cells into the lung parenchyma and impairs the development of ectopic lymphoid structures associated with reduced expression of the chemokine receptors CXCR5 and CCR7. Together, our data support a role for BCG vaccination in preventing the immunosuppressive effects of IL-10 in the fast progression of Mtb infection and may provide valuable insights on the mechanisms contributing to the variable efficacy of BCG vaccination.

High level of γH2AX phosphorylation in the cord-blood cells of large-for-gestational-age (LGA) newborns.

Newborns can experience adverse effects as a consequence of maternal or in utero exposure, altered growth of the fetus, or placental dysfunctions. Accurate characterization of gestational age allows monitoring of fetal growth, identification of deviations from the normal growth trajectory, and classification of babies as adapted, small, or large for gestational age (AGA, SGA, or LGA). The aim of this work was to evaluate nuclear and oxidative damage in umbilical cord-blood cells of newborns (sampled at birth), by applying the γH2AX assay and the fluorescent probe BODIPY581/591 C11, to detect DNA DSB and cell membrane oxidation, respectively. No statistically significant differences were observed in the proportion of oxidized cord-blood cells among the groups of newborns, although the LGA group showed the highest value. With regard to genome damage, elevated levels of γH2AX foci were detected in the cell nuclei from LGA newborns as compared to AGA or SGA babies, whose values did not differ from each other. Considering that the observed DNA damage, although still repairable, can represent a risk factor for obesity, metabolic diseases, or other pathologies, monitoring genome and cell integrity at birth can provide useful information for prevention of diseases later in life.

UCTD and SLE patients show increased levels of oxidative and DNA damage together with an altered kinetics of DSB repair.

Immunological tolerance is a critical feature of the immune system; its loss might lead to an abnormal response of lymphocytes causing autoimmune diseases. One of the most important groups belonging to autoimmune disorders is the connective tissue diseases (CTD). CTD are classified among systemic rheumatic diseases and include pathologies such as systemic lupus erythematosus (SLE), and undifferentiated CTD (UCTD). In this study, we evaluated oxidative and genome damage in peripheral blood lymphocytes from patients with SLE and UCTD, further classified on the basis of disease activity and the presence/absence of a serological profile. Oxidative damage was evaluated in cell membrane using the fluorescent fatty acid analogue BODIPY581/591 C11. The percentage of oxidised lymphocytes in both SLE and UCTD patients was higher than in the control group, and the oxidative stress correlated positively with both disease activity and autoantibody profile. The γH2AX focus assay was used to quantify the presence of spontaneous double strand breaks (DSBs), and to assess the abilities of DSBs repair system after T cells were treated with mitomycin C (MMC). Subjects with these autoimmune disorders showed a higher number of γH2AX foci than healthy controls, but no correlation with diseases activity and presence of serological profile was observed. In addition, patients displayed an altered response to MMC-induced DSBs, which led their peripheral cells to greatly increase apoptosis. Taken together our results confirmed an interplay among oxidative stress, DNA damage and impaired DNA repair, which are directly correlated to the aggressiveness and clinical progression of the diseases. We propose the evaluation of these molecular markers to better characterise SLE and UCTD, aiming to improve the treatment plan and the quality of the patients' life.

Role of oxidative stress, genome damage and DNA methylation as determinants of pathological conditions in the newborn: an overview from conception to early neonatal stage.

Increasing evidence suggests that early-life events can predispose the newborn to a variety of health issues in later life. In adverse pre- and perinatal conditions, oxidative stress appears to play an important role in the development of future pathological outcomes. From a molecular point of view, oxidative stress can result in genome damage and changes in DNA methylation that can in turn prime pathogenic mechanisms. Interestingly, both alterations have been related to a reciprocal regulation of oxidative stress. The aim of this review is to give a brief overview of the complex relationship linking oxidative stress to DNA damage and methylation and to go through the different sources of exposure that a neonate can encounter in utero or shortly after birth. In this context, the setup of methodologies to monitor the extent of oxidative stress, genomic damage and instability or the presence of altered methylation patterns contributes to the understanding on how the complex events occurring in early life can lead to either a healthy status or a pathological condition.