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1.
Arch Toxicol ; 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38494580

RESUMO

Cannabis is the most used illicit substance for recreational purposes around the world. However, it has become increasingly common to witness the use of approved cannabis preparations for symptoms management in various diseases. The aim of this study was to investigate the effects of cannabis nano emulsion in the liver of Wistar rats, with different proportions of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). For this, a total of 40 male Wistar rats were distributed into 5 groups, as follows (n = 8 per group): Control: G1, Experimental group (G2): treated with cannabis nano emulsion (THC and CBD) at a dose of 2.5 mg/kg, Experimental group (G3): treated with cannabis nano emulsion (THC and CBD) at a dose of 5 mg/kg, Experimental group (G4): treated with cannabis nano emulsion (CBD) at a dose of 2.5 mg/kg; Experimental group (G5): treated with cannabis nano emulsion (CBD) at a dose of 5 mg/kg. Exposure to the nano emulsion was carried out for 21 days, once a day, orally (gavage). Our results showed that cannabis nano emulsions at higher doses (5 mg/kg), regardless of the composition, induced histopathologic changes in the liver (G3 and G5) in comparison with the control group. In line with that, placental glutathione S-transferase (GST-P) positive foci increased in both G3 and G5 (p < 0.05), as well as the immune expression of Ki-67, vascular endothelial growth factor (VEGF) and p53 (p < 0.05). Also, the nano emulsion intake induced an increase in the number of micronucleated hepatocytes in G5 (p < 0.05) whereas G3 showed an increase in binucleated cells (p < 0.05). As for metanuclear alterations, karyolysis and pyknosis had an increased frequency in G3 (p < 0.05). Taken together, the results show that intake of cannabis nano emulsion may induce degenerative changes and genotoxicity in the liver in higher doses, demonstrating a clear dose-response relationship.

2.
Neurobiol Learn Mem ; 209: 107902, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336097

RESUMO

Calorie restriction (CR) is a non-invasive and economic approachknown to increase healthspan and life expectancy, through a decrease in oxidative stress, an increase in neurotrophins, among other benefits. However, it is not clear whether its benefit could be noted earlier, as at the beginning of middle-age. Hence, weaimed to determine whether six months of long-term CR, from early adulthood to the beginning of middle age (10 months of age) could positively affect cognitive, neurochemical, and behavioral parameters. Male C57BL6/J mice were randomly distributed into Young Control (YC, ad libitum food), Old Control (OC, ad libitum food), and Old Restricted (OR, 30 % of caloric restriction) groups. To analyze the cognitive and behavioral aspects, the novel object recognition task (NOR), open field, and elevated plus maze tests were performed. In addition, immunohistochemistry targetingΔFosB (neuronal activity), brain-derived neurotrophic factor (BDNF) and the DNA oxidative damage (8OHdG) in hippocampal subfields CA1, CA2, CA3, and dentate gyrus (DG), and in basolateral amygdala and striatum were performed. Our results showed that long-term CR prevented short-term memory impairment related to aging and increased 8OHdG in hippocampal DG. BDNF was not involved in the effects of either age or CR on memory at middle-age, as it increased in CA3 of the OC group but was not altered in OR. Regarding anxiety-type behavior, no parameter showed differences between the groups. In conclusion, while the effects of long-term CR on anxiety-type behavior were inconclusive, it mitigated the memory deficit related to aging, which was accompanied by an increase in hippocampal 8OHdG in DG. Future studies should investigate whether the benefits of CR would remain if the restriction were interrupted after this long-term protocol.


Assuntos
Restrição Calórica , Estresse Oxidativo , Camundongos , Animais , Masculino , 8-Hidroxi-2'-Desoxiguanosina , Hipocampo/fisiologia , DNA , Transtornos da Memória/prevenção & controle , Giro Denteado
3.
Exp Brain Res ; 240(12): 3107-3140, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36264315

RESUMO

This systematic review (SR) was aimed at answering two questions: (1) how sex and ovarian hormones alter behavior associated with cocaine use; (2) which possible neurobiological mechanisms explain behavioral differences. Three different researchers conducted a search in PUBMED for all kinds of articles published between the years of 1991 to 2021 on the theme "reproductive cycle and cocaine", "estrous cycle and cocaine", "menstrual cycle and cocaine", "fluctuation of ovarian hormones and cocaine", "estrogen and cocaine" and "progesterone and cocaine". Sixty original studies were identified and subdivided into experimental rodent studies and clinical trials. Experimental studies were characterized by author/year, species/strain, sex/number, age/weight, dose/route/time of administration, hormonal assessment, or administration. Clinical trials were characterized by author/year, sex/number, age, exclusion criterion, dose/route of administration/time of cocaine, and hormonal assessment. Results gathered showed that rodent females develop increased consumption, seeking behavior, craving, relapse, locomotion, increases in stress and anxiety, among other behavioral alterations during peaks of estrogen. These observations are related to the direct effects played by ovarian hormones (in particularly estradiol), in dopamine, but also in serotonin neurons, and in brain regions such as the tegmental area, the nucleus accumbens, the hypothalamus, the amygdala and the prefrontal cortex. Increased sensitization to cocaine presented by high estradiol females was linked to the activation of a CBR1-mediated mechanism and GABA-A-dependent suppression of inhibitory synaptic activity of the prelimbic prefrontal cortex. Estradiol facilitation of cocaine-increased locomotion and self-administration was shown to require the release of glutamate and the activation of metabotropic glutamate receptors subtype 5. Clinical studies also tend to point to a stimulatory effect of estradiol on cocaine sensitization and a neuroprotective effect of progesterone. In conclusion, the results of the present review indicate a need for further preclinical and clinical trials and neurobiological studies to better understand the relationship between sex and ovarian hormones on cocaine sensitization.


Assuntos
Cocaína , Humanos , Feminino , Cocaína/farmacologia , Progesterona/farmacologia , Ovariectomia , Estradiol/farmacologia , Estrogênios/farmacologia
4.
Environ Sci Pollut Res Int ; 29(43): 64392-64403, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35854069

RESUMO

The systematic review (SR) with meta-analysis aimed to infer if micronucleus assay using oral mucosal cells a useful biomarker for biomonitoring populations continuously exposed to pesticides (EP). The SR has been made in accordance with the PRISMA-P guidelines. The PICOS strategy has focused to answer the following question: "Does exposure to pesticides cause genetic damage in oral cells?" The literature search was made in the following scientific databases: Web of Science, PubMed/Medline, and Scopus. The approach was defined as follows: standardized mean difference (SMD) and 95% confidence intervals (CI). The quality assessment of manuscripts was obtained by the EPHPP (Effective Public Health Practice Project). The GRADE tool was chosen for assessing the quality of evidence. A total of 108 articles were selected in this setting. After screening abstracts and titles, 23 manuscripts were evaluated for eligibility. After reviewing the studies, two were considered weak and 22 were classified as moderate or strong. The meta-analysis data pointed out statistically significant differences in volunteers exposed to EP (SMD = 1.23, 95% CI, 0.69 to 1.77, p < 0.001), with a Tau2 = 1.44; Chi2 = 566.38, and p < 0.001, so that the selected manuscripts were considered heterogeneous and the I2 of 97% indicated high heterogeneity. Taken together, this review was able to validate the micronucleus assay in oral exfoliated cells as a useful biomarker in individuals continuously exposed to EP because the studies categorized as moderate and strong have demonstrated positive response related to mutagenesis.


Assuntos
Praguicidas , Humanos , Monitoramento Biológico , Biomarcadores , Metanálise como Assunto , Testes para Micronúcleos , Praguicidas/toxicidade
5.
Pathol Res Pract ; 232: 153828, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35279481

RESUMO

This systematic review (SR) with meta-analysis aimed to evaluate the scientific data related to cytogenetic damage in oral exfoliated cells of patients diagnosed with oral potentially malignant disorders (OPMDs). The SR was conducted according to the PRISMA-P guidelines. The PICOS (Participants, Intervention, Comparison, Outcome, and Study Design) strategy was used to answer the question: "Is micronucleus assay in oral exfoliated cells a suitable biomarker for predicting cancer risk in individuals with OPMDs?" The search strategy was performed in the following electronic databases: PubMed, Medline, Scopus and Web of Science. The comparisons were defined as standardized mean difference (SMD), and 95% confidence intervals (CI). The quality of included studies was assessed using the EPHPP (Effective Public Health Practice Project). The GRADE tool was also utilized to assess the quality of evidence of the SR. A total of 110 potentially relevant studies were selected through the search strategy. After screening titles and abstracts, 20 full-text manuscripts were assessed for eligibility and three observational studies were included in the meta-analysis. After reviewing the 20 studies, 13 were considered weak. The meta-analysis data revealed a statistically significant difference in oral micronucleated cells by patients with OPMDs when compared to control (SMD=1.77, 95% CI, 0.36-3.18, p = 0.01), with a Tau2 = 1.97; Chi2 = 66.64, and p < 0.001. Patients with OPMDs had a positive response related to mutagenicity in oral cells compared to control patients. However, SR was not able to validate the micronucleus assay as a putative biomarker in individuals with oral potentially malignant disorders since the majority of studies were considered weak based on high risk of bias.


Assuntos
Neoplasias Bucais , Lesões Pré-Cancerosas , Biomarcadores , Humanos , Testes para Micronúcleos
6.
Exp Brain Res ; 239(4): 1179-1191, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33569614

RESUMO

Crack cocaine is the crystal form of cocaine, produced by adding sodium bicarbonate to cocaine base paste. Brazil is the largest consumer of crack cocaine in the world. Users of crack cocaine show important physiological and behavioral alterations, including neuropsychiatric symptoms, such as anxiety-related symptoms. Nevertheless, few pre-clinical studies have been previously performed to understand the neurobiological effects of crack cocaine. The purpose of the present study was to investigate effects of the subchronic treatment (5 days, IP) of rats with crack cocaine in an animal model of anxiety/panic, the elevated T-maze (ETM). The ETM model allows the measurement of two behavioral defensive responses, avoidance and escape, in clinical terms, respectively, associated to generalized anxiety and panic disorder, the two main psychiatric conditions that accompany substance use disorders. Immediately after the ETM model, animals were tested in an open field for locomotor activity assessment. Analysis of delta FosB protein immunoreactivity was used to map areas activated by crack cocaine exposure. Results showed that crack treatment selectively altered escape displayed by rats in the ETM test, inducing either a panicolytic (18 mg/kg IP) or a panicogenic-like effect (25 and 36 mg/kg IP). These effects were followed by the altered functioning of panic-modulating brain regions, i.e., the periaqueductal gray and the dorsal region and lateral wings of the dorsal raphe nucleus. Treatment with 36 mg/kg of crack cocaine also increased locomotor activity. These are the first observations performed with crack cocaine in a rodent model of anxiety/panic and contribute to a better understanding of the behavioral and neurobiological effects of crack cocaine.


Assuntos
Cocaína Crack , Animais , Ansiedade/induzido quimicamente , Núcleo Dorsal da Rafe , Reação de Fuga , Aprendizagem em Labirinto , Proteínas Proto-Oncogênicas c-fos , Ratos , Ratos Wistar
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