02168naa a2200277 a 450000100080000000500110000800800410001902400520006010000260011224501540013826000090029252013190030165000110162065300230163165300240165465300180167865300240169670000160172070000200173670000190175670000190177570000220179470000130181670000200182977300410184921542862023-08-22       2023    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s11756-023-01325-62DOI1 aSIQUEIRA, J. T. da C.  aChromosomal aberrations and changes in the methylation patterns of Lactuca sativa L. (Asteraceae) exposed to carbon nanotubes.h[electronic resource]  c2023  aCarbon nanotubes (CNTs) are one of the most important nanomaterials, with applications in several areas. The exponential increase in the production and use of CNTs, however, increases the likelihood of their release into the environment and potential impacts on environmental systems. We evaluated the cytogenotoxic potential of carboxylated multi-walled carbon nanotubes (MWCNT-COOH) as well as its influence in the methylation patterns of Lactuca sativa meristematic cells. Root elongation was observed at concentrations of 1.0; 10.0; 50.0 and 100.0 μg/mL, and decreased seed germination at the highest concentration evaluated (100 ug/mL). Cytogenetic analysis revealed that MWCNT-COOH induced increases in the chromosomal aberration index and micronucleus frequency. Accumulations of cells in the sub G1 phase were also observed at low concentrations (0.1 μg / mL), which may be related to increased programmed cell death. Cytosine methylation profile analysis revealed cytosine hypermethylation at MWCNT-COOH concentrations of 1.0 and 10.0 μg / mL and cytosine hypomethylation at MWCNT-COOH concentrations of 50.0 and 100.0 μg / mL as compared to controls. We conclude that, in addition to cytogenotoxic effects, MWCNT-COOH alters cytosine methylation profiles and promotes root elongation.  aAlface  aCitogenotoxicidade  aCitometria de fluxo  aMorte celular  aNanotubo de carbono1 aREIS, A. C.1 aLOPES, J. M. L.1 aLADEIRA, L. O.1 aVICCINI, L. F.1 aBRANDAO, H. de M.1 aMUNK, M.1 aSOUSA, S. M. de  tBiologiagv. 78, p. 1991-2002, 2023.