Social distancing and changes in drug use: Results from a cross-sectional study during the COVID-19 pandemic in Brazil.

Background: The outbreak of coronavirus disease 19 has led to measures of social distancing and quarantine worldwide. This stressful period may lead to psychological problems, including changes in substance use. In addition, sociodemographic factors are linked to changed levels of drug use and abuse observed during the COVID-19 pandemic, which are also associated with increased anxiety, depression, and other disorders. Thus, the aim of the study was to investigate (i) changes in drug use during the COVID-19 pandemic associated with social distancing, and (ii) to verify factors associated with those changes. Methods: A web-based cross-sectional observational survey was completed by a self-selected adult general population in Brazil (N = 2,435) during September/October 2020 (first wave) before and throughout the pandemic. Key outcomes: social distancing, self-reported drug use (ASSIST), and emotional states (DASS-21). Results: High social distancing was associated with fewer chances (prevalence ratio) of increased drug use for alcohol (0.71, CI95%: 0.64-0.80), tobacco (0.72; CI95%: 0.60-0.87), cannabis (0.65; CI95%: 0.55-0.78), and others. Low social distancing presented a higher DASS-21 score for anxiety (P = 0.017). Concerning covariates analysis by a general linear model, men (alcohol: 1. 71; cannabis: 3.86), younger age (alcohol: 0.97), less education (alcohol, tobacco, cannabis and cocaine/crack comparing several lower schooling categories vs. higher education), lower income (alcohol: 0.42; tobacco: 0.47; and cannabis: 0.36), and higher depression DASS-21 score (alcohol: 1.05; tobacco: 1.08; cannabis: 1.07; and cocaine/crack: 1.07) were associated with higher use prevalence of several drugs. Conclusions: Individuals reporting low social distancing increased the use of most drugs during the pandemic, while high social distancing significantly decreased drug use. Anxiety and depressive states and several sociodemographic factors (men; lower income; less education) were associated with higher drug use patterns.

Low-cost apparatus for cigarette smoke exposure in rats.

BACKGROUND: The effects of tobacco smoke on the central nervous system are usually studied with isolated nicotine, ignoring other compounds present in cigarette smoke. The few studies that use in vivo whole-body cigarette smoke exposure are usually performed in expensive commercial apparatus. NEW METHOD: We presented a feasible, safe, and low-cost apparatus for cigarette smoke exposure in rodents. RESULTS: Rats exposed to cigarette smoke in this apparatus showed cotinine levels similar to human active smokers. Additional results showed that cigarette smoke exposure increased glutamate and aspartic acid levels and decreased leucine, isoleucine, ornithine, phenylalanine, and tryptophan levels in the cerebrospinal fluid of rats. COMPARISON WITH EXISTING METHOD(S): Our apparatus is feasible, safe, and costs 67-fold less than a commercial automatized smoking machine. Beyond the low cost, it does not require specialized knowledge for building or maintenance. CONCLUSIONS: We concluded that our low-cost apparatus is reliable and reproduces cigarette smoke use in humans.

Levamisole, a cocaine cutting agent, induces acute and subchronic systemic alterations in Wistar rats.

The use of the anthelmintic levamisole as a cocaine adulterant has been increasing worldwide. Complications caused by this association include systemic vasculitis, agranulocytosis, neutropenia, tissue necrosis, pulmonary hemorrhage, and renal injury. Data about toxicity of levamisole are scarce, therefore the aim of this study was to evaluate the acute and subchronic toxic effects of levamisole in rats. Male Wistar rats received saline or levamisole by intraperitoneal route at the doses of 12, 24 and 36 mg/kg in the acute toxicity test; and at 3, 6 and 12 mg/kg in the subchronic toxicity test. Toxicity was evaluated using behavioral, cognitive, renal, hematological, biochemical and histopathological parameters. Acute administration of levamisole caused behavioral and histopathological alterations. Subchronic administration caused behavioral, cognitive and hematological alterations (p < 0.0001 and p < 0.05, respectively), impairment of liver and kidney functions (p < 0.05), and changes of antioxidant defenses (p ≤ 0.0001). Both administrations produced toxic effects of clinical relevance, which make levamisole a dangerous cutting agent. Furthermore, the knowledge of these effects can contribute to the correct diagnosis and treatment of cocaine dependents with unusual systemic alterations.

Sintocalmy, a Passiflora incarnata Based Herbal, Attenuates Morphine Withdrawal in Mice.

Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.

Taurine enhances voluntary alcohol intake and promotes anxiolytic-like behaviors in rats.

Taurine is an amino acid usually added to energy drinks. In rodents, acute taurine administration decreases voluntary alcohol intake, and subchronic administration restores different behavioral features impaired by alcohol withdrawal. In the present study, we evaluated the effects of chronic taurine treatment on voluntary alcohol consumption and changes in behavioral parameters in rats. Adult male Wistar rats were divided into two groups and were allowed to choose from two bottles containing 20% alcohol or 0.08% saccharin (vehicle solution), or two bottles containing vehicle, 24 h per day, for 5 weeks. After 3 weeks, rats received 100 mg/kg taurine (TAU) or saline (SAL) intraperitoneally once a day for 2 weeks, and daily alcohol consumption was monitored. On days 22 and 33, rats were tested in the open-field, and on day 34, they were exposed to the light/dark task (LDT). Our results show for the first time that chronic taurine treatment enhanced voluntary alcohol intake and preference in rats, and that these changes were accompanied by an anxiolytic-like phenotype in alcohol-treated rats, possibly due to its synergistic effect with alcohol on the dopaminergic and GABAergic systems.