Genotoxicity of Marijuana in Mono-Users

Abstract

Marijuana (Cannabis sp.) is among the most recurred controlled substances in the world, and there is a growing tendency to legalize its possession and use; however, the genotoxic effects of marijuana remain under debate. A clear definition of marijuana's genotoxic effects remains obscure by the simultaneous consumption of tobacco and other recreational substances. In order to assess the genotoxic effects of marijuana and to prevent the bias caused by the use of substances other than cannabis, we recruited marijuana users that were sub-divided into three categories: (1) users of marijuana-only (M), (2) users of marijuana and tobacco (M+T), and (3) users of marijuana plus other recreative substances or illicit drugs (M+O), all the groups were compared against a non-user control group. We quantified DNA damage by detection of γH2AX levels and quantification of micronuclei (MN), one of the best-established methods for measuring chromosomal DNA damage. We found increased levels of γH2AX in peripheral blood lymphocytes from the M and M+T groups, and increased levels of MNs in cultures from M+T group. Our results suggest a DNA damage increment for M and M+T groups but the extent of chromosomal damage (revealed here by the presence of MNs and NBuds) might be related to the compounds found in tobacco. We also observed an elevated nuclear division index in all marijuana users in comparison to the control group suggesting a cytostatic dysregulation caused by cannabis use. Our study is the first in Mexico to assess the genotoxicity of marijuana in mono-users and in combination with other illicit drugs.

Amelioration of Cytogenotoxic Damage in Drug Abusers Supplemented with Folic Acid

“…It has been demonstrated that smoked marijuana, either alone or in combination with tobacco, is capable of inducing genetic damage and cytotoxicity in the cells of the oral mucosa and peripheral blood of consumers. This is evidenced by a study conducted by Souza DV et al, where there was an increase in MNs and KL, as well as by a study carried out by Fabian-Morales E et al, in which genotoxic damage was also demonstrated through an increase in MNs and BUDs [24,55].…”

Cytotoxic and genotoxic effects of cigarette and waterpipe tobacco smoking on buccal mucosa: A systematic review and meta-analysis

“…After the removal of duplicates, 32 were evaluated for the inclusion and exclusion criteria. After careful analysis, 20 articles were included[ 4 5 13 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 ] and after comprehensive evaluation of the titles, abstracts, resulted in the exclusion of 12 articles[ 1 3 9 12 34 35 36 37 38 39 40 41 ] The reason for exclusion was due to incomplete articles, conference abstracts, articles other than the English language, retrospective studies, animal studies, editorial letters, studies on Marijuana and Nargile users and studies on blood and saliva, gingiva and those not following inclusion criteria were excluded, as shown in Figure 1 , according to PICO framework.…”

Genotoxic Aspects of Psychoactive Substances

“…Recently, the genotoxicity observed in the peripheral lymphocytes from marijuana monousers was compared with those presented in marijuana and tobacco users. While the increase in the formation of γ-H2AX (early biomarker that reflects the formation of double-strand breaks) was present in both groups, the formation of MN was only present in the individuals concomitantly exposed to both agents [10]. Marijuana smoke condensates displayed positive results in the cytokinesis-block micronucleus assay and comet assay in human lung cancer cells with differential p53 expression [11].…”