Catequinas del té verde: efectos antigenotóxicos y genotóxicos. Revisión sistemática / Green tea catechins: antigenotoxic and genotoxic effects. Systematic review

Las catequinas del té verde (Camellia sinensis) (CTV) presentan efectos benéficos para la salud asociados a su potencial antioxidante. Por otra parte, el estrés oxidante es una de las vías de inducción de daño genotóxico. De ahí que, en la presente revisión se realizó un análisis de los efectos antigenotóxicos y genotóxicos de las CTV, haciendo énfasis en las vías implicadas en estos procesos y sus efectos en la salud. Se realizó una revisión de artículos indexados en las bases de datos de PubMed® y Science Direct® (2021) con las palabras clave "green tea" y "green tea catechins". Se delimitaron los estudios utilizando los operadores booleanos "AND", "OR" y "NOT" ("antigenotoxic", "genotoxic", "antioxidant" y "prooxidant"). En su mayoría se consideraron las publicaciones del 2016 al 2021. Se observó que los efectos benéficos en la salud de las CTV están relacionados con: a) su actividad antioxidante mediante la captura, inhibición y prevención de la formación de las especies reactivas de oxígeno; b) la regulación del sistema antioxidante endógeno; c) la activación de los mecanismos de reparación al contribuir en la eliminación del aducto 8-hidroxi-2'-desoxiguanosina; d) la inducción de apoptosis en células con daño al ADN; y e) la inhibición de la inflamación relacionada con su actividad antiapoptótica. Si bien, en algunos de los estudios se reportaron efectos genotóxicos, estos a su vez contribuyeron en la eliminación de células con daño genético, por lo que, no se puede considerar del todo a la actividad genotóxica de las CTV como perjudiciales para la salud(AU)

The green tea catechins (Camellia sinensis) (CTV) have beneficial effects for health associated with their antioxidant potential. Moreover, oxidative stress is one of the pathways for inducing genotoxic damage. Hence, in this review, an analysis of the antigenotoxic and genotoxic effects of CTV was carried out, emphasizing the pathways involved in these processes and their effects on health. A review of articles indexed in the PubMed® and ScienceDirect® (2021) databases with the keywords "green tea" and "green tea catechins" was carried out. Studies were delimited using the Boolean operators "AND", "OR" and "NOT" ("antigenotoxic", "genotoxic", "antioxidant" and "prooxidant"). For the most part, publications from 2016 to 2021 were considered. It was observed that the beneficial health effects of CTVs are related to: a) their antioxidant activity through the capture, inhibition and prevention of the formation of reactive oxygen species; b) the regulation of the endogenous antioxidant system; c) the activation of the repair mechanisms by contributing to the elimination of the 8-hydroxy-2'-deoxyguanosine adduct; d) the induction of apoptosis in cells with DNA damage; and e) the inhibition of inflammation related to its antiapoptotic activity. Although some of the studies reported genotoxic effects, these in turn contributed to the elimination of cells with genetic damage. Therefore, the genotoxic activity of CTV cannot be considered as harmful to health

Chemopreventive activity of phenylalanine against damage mutagenic prompted by the acute administration of cyclophosphamide in pregnant and non-pregnant mice using the micronucleus test / Atividade quimiopreventiva da fenilalanina contra danos mutagênicos pela administração aguda de ciclofosfamida em ratas grávidas e não grávidas, utilizando o teste do micronúcleo

This study aimed to evaluate the quimiopreventive ability of phenylalanine. We used pregnant and non-pregnant female mice divided into the following groups: G1-PBS, (0.1 mL/kg b.w); G2, cyclophosphamide (35 mg/kg p.c.-i.p.); G3 and G4, phenylalanine (150 and 300 mg/kg b.w respectively-v.o.) and G5 and G6, association between the two doses of phenylalanine and cyclophosphamide, respectively. The peripheral blood samples were taken at T0, before the administration of any drug test and / or vehicles, also at T24 and T48 where the collections were made 24 and 48 h after administration of cyclophosphamide, respectively. A general analysis has found that, for the group of non-pregnant female, the antimutagenic evaluation showed reduction percentages of damage of 57.24 percent and 31.64 percent for G5 and G6, respectively, at T24, and 29.32 percent and 24.13 percent for G5 and G6, respectively, at T48. Antimutagenic pregnant animals in the 24 h quimiopreventive efficiency shown only for the lower dose (G5) and the percentages of reduction were 43.25 percent in G5 and G6 at 18.47 percent. At T48 the harm-reduction percentages were 44.67 percent and 37.76 percent for G5 and G6, respectively.

A presente pesquisa teve por objetivo avaliar a capacidade quimiopreventiva da fenilalanina. Utilizou-se um lote de fêmeas prenhes e não prenhes divididas nos seguintes grupos experimentais: G1, PBS (0,1 mL/kg p.c.); G2, ciclofosfamida (35 mg/kg p.c.-i.p.); G3, fenilalanina (150 mg/kg p.c.-v.o.) e G4, fenilalanina (300 mg/kg p.c.-v.o.) e G5 (150 mg/kg p.c. de fenilalanina e 35 mg/kg de ciclofosfamida); G6, (300 mg/kg p.c. de fenilalanina e 35 mg/kg de ciclofosfamida). As coletas de sangue periférico foram realizadas em T0, antes da administração de qualquer substância teste e/ou veículos, e igualmente em T24 e T48, onde as coletas foram realizadas respectivamente 24 e 48 h após a administração da ciclofosfamida. Em uma análise geral verificou-se que, para o grupo de fêmeas não prenhes, a avaliação da antimutagenicidade demonstrou porcentagens de redução de danos de 57,24 por cento e 31,64 por cento para G5 e G6, respectivamente, em T24, e 29,32 por cento e 24,13 por cento para G5 e G6, respectivamente, em T48. Nos animais prenhes a antimutagenicidade de 24 h demonstrou eficiência quimiopreventiva apenas para a menor dose (G5) e as porcentagens de redução de danos foram de 43,25 por cento em G5 e 18,47 por cento em G6. No momento T48 as porcentagens de redução de danos foram de 44,67 por cento e 37,76 por cento para G5 e G6, respectivamente.