Genotoxicity and hypomethylation of LINE-1 induced by electronic cigarettes

Currently, the marketing of electronic cigarettes as a safe alternative to smoking has increased, which is associated with greater use of these devices, especially among young people and smokers interested in quitting tobacco cigarettes. Given the growing use of this type of product, there is a need to determine the consequences of electronic cigarettes on human health, especially since many of the compounds contained in the aerosol and liquid of these devices have a high potential to be carcinogenic and genotoxic. Additionally, many of these compounds' aerosol concentrations exceed the safe limits. We have evaluated the levels of genotoxicity and changes in DNA methylation patterns associated with vaping. We analyzed a total of 90 peripheral blood samples from a population of vapers (n = 32), smokers (n = 18), and controls (n = 32), in which the frequencies of genotoxicity were determined by the cytokinesis-blocking micronuclei (CBMN) assay and the patterns of methylation of the repetitive elements of LINE-1 through the Quantitative Methylation Specific PCR (qMSP) assay. Here we show an increase in genotoxicity levels associated with vaping habits. Additionally, the group of vapers showed changes at the epigenetic level specifically associated with the loss of methylation of the LINE-1 elements. These changes in LINE-1 methylation patterns were reflected in its representative RNA expression detected in vapers.

Correlation of the Glomerular Filtration Rate Measured With the Use of DTPA-Tc99m in Live Kidney Donors With Equations Based on Creatinine and Cystatin C

BACKGROUND

Renal donation leads to a risk of developing chronic kidney disease, with an incidence of 0.47%. To evaluate for its presence, formulas based on serum creatinine are used, but up to 80% of these formulas underestimate the glomerular filtration rate (GFR) in donors. The aim of this work was to confirm the highest correlation of the GFR as measured with the use of DTPA-Tc99m with the GFR as estimated by means of the formula based on serum cystatin C (CKD-EPI creatinine-cystatin C) in healthy kidney donors.

METHODS

In this observational, analytic, cross-sectional study, the GFR of kidney donors was determined ≥1 year after donation by means of DTPA gammagram and estimation with the use of conventional formulations and with cystatin C.

RESULTS

Of 112 donors, 38 (34%) were included, 20 (60%) were female, with an overall average age of 40 years, 36.5 months after donation, and body mass index of 25.5 kg/m². Correlation with the GFR as measured by means of DTPA gammagram was better with the use of CKD-EPI cystatin C (0.402; P = .020) and CKD-EPI creatinine-cystatin (0.549; P < .001) than the conventional formulas. Linear correlation with serum cystatin C was 0.825 (P < .001; 95% confidence interval, -105.3 to -63.2) for the CKD-EPI cystatin C formula, 0.77 (P < .001; -89.9 to -48.1) for the CKD-EPI creatinine-cystatin formula, and 0.525 (P = .002; -91.1 to -23.2) for DTPA-Tc99m scintigraphy.

CONCLUSIONS

There is a strong correlation between estimate the GFR by equations based on cystatin C and the measurement of the GFR by DTPA-Tc99m gammagram.