Neural basis of anxiolytic effects of cannabidiol (CBD) in generalized social anxiety disorder: a preliminary report

Animal and human studies indicate that cannabidiol (CBD), a major constituent of cannabis, has anxiolytic properties. However, no study to date has investigated the effects of this compound on human pathological anxiety and its underlying brain mechanisms. The aim of the present study was to investigate this in patients with generalized social anxiety disorder (SAD) using functional neuroimaging. Regional cerebral blood flow (rCBF) at rest was measured twice using (99m)Tc-ECD SPECT in 10 treatment-naive patients with SAD. In the first session, subjects were given an oral dose of CBD (400 mg) or placebo, in a double-blind procedure. In the second session, the same procedure was performed using the drug that had not been administered in the previous session. Within-subject between-condition rCBF comparisons were performed using statistical parametric mapping. Relative to placebo, CBD was associated with significantly decreased subjective anxiety (p < 0.001), reduced ECD uptake in the left parahippocampal gyrus, hippocampus, and inferior temporal gyrus (p < 0.001, uncorrected), and increased ECD uptake in the right posterior cingulate gyrus (p < 0.001, uncorrected). These results suggest that CBD reduces anxiety in SAD and that this is related to its effects on activity in limbic and paralimbic brain areas.

The frontal assessment battery (FAB) reveals neurocognitive dysfunction in substance-dependent individuals in distinct executive domains: Abstract reasoning, motor programming, and cognitive flexibility

Substance-dependence is highly associated with executive cognitive function (ECF) impairments. However. considering that it is difficult to assess ECF clinically, the aim of the present study was to examine the feasibility of a brief neuropsychological tool (the Frontal Assessment Battery FAB) to detect specific ECF impairments in a sample of substance-dependent individuals (SDI). Sixty-two subjects participated in this study. Thirty DSM-IV-diagnosed SDI, after 2 weeks of abstinence, and 32 healthy individuals (control group) were evaluated with FAD and other ECF-related tasks: digits forward (DF), digits backward (DB), Stroop Color Word Test (SCWT), and Wisconsin Card Sorting Test (WCST). SDI did not differ from the control group on sociodemographic variables or IQ. However, SDI performed below the controls in OF, DB, and FAB. The SDI were cognitively impaired in 3 of the 6 cognitive domains assessed by the FAB: abstract reasoning, motor programming, and cognitive flexibility. The FAB correlated with DF, SCWT, and WCST. In addition, some neuropsychological measures were correlated with the amount of alcohol, cannabis, and cocaine use. In conclusion, SDI performed more poorly than the comparison group on the FAB and the FAB`s results were associated with other ECF-related tasks. The results suggested a negative impact of alcohol, cannabis, and cocaine use on the ECF. The FAB may be useful in assisting professionals as an instrument to screen for ECF-related deficits in SDI. (C) 2010 Elsevier Ltd. All rights reserved.

Cannabidiol was ineffective for manic episode of bipolar affective disorder

The pharmacological profile of cannabidiol (CBD) has several characteristics in common with drugs known to benefit bipolar affective disorder (BAD), leading to the hypothesis that CBD may have therapeutic properties in BAD. Therefore, the aim of the present report was to directly investigate for the first time the efficacy and safety of CBD in two patients with BAD. Both patients met DSM IV criteria for bipolar I disorder experiencing a manic episode without comorbid conditions. This was an inpatient study, and the efficacy, tolerability and side effects were assessed. Both patients received placebo for the initial 5 days and CBD from the 6th to 30th day (initial oral dose of 600 mg reaching 1200 mg/day). From the 6th to the 20th day, the first patient (a 34-year-old woman) received adjunctive olanzapine (oral dose of 10-15 mg). On day 31, CBD treatment was discontinued and replaced by placebo for 5 days. The first patient showed symptoms improvement while on olanzapine plus CBD, but showed no additional improvement during CBD monotherapy. The second patient (a 36-year-old woman) had no symptoms improvement with any dose of CBD during the trial. Both patients tolerated CBD very well and no side-effects were reported. These preliminary data suggest that CBD may not be effective for the manic episode of BAD.

Modulation of Auditory and Visual Processing by Delta-9-Tetrahydrocannabinol and Cannabidiol: an fMRI Study

Although the effects of cannabis on perception are well documented, little is known about their neural basis or how these may contribute to the formation of psychotic symptoms. We used functional magnetic resonance imaging (fMRI) to assess the effects of Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) during visual and auditory processing in healthy volunteers. In total, 14 healthy volunteers were scanned on three occasions. Identical 10mg THC, 600mg CBD, and placebo capsules were allocated in a balanced double-blinded pseudo-randomized crossover design. Plasma levels of each substance, physiological parameters, and measures of psychopathology were taken at baseline and at regular intervals following ingestion of substances. Volunteers listened passively to words read and viewed a radial visual checkerboard in alternating blocks during fMRI scanning. Administration of THC was associated with increases in anxiety, intoxication, and positive psychotic symptoms, whereas CBD had no significant symptomatic effects. THC decreased activation relative to placebo in bilateral temporal cortices during auditory processing, and increased and decreased activation in different visual areas during visual processing. CBD was associated with activation in right temporal cortex during auditory processing, and when contrasted, THC and CBD had opposite effects in the right posterior superior temporal gyrus, the right-sided homolog to Wernicke`s area. Moreover, the attenuation of activation in this area (maximum 61, -15, -2) by THC during auditory processing was correlated with its acute effect on psychotic symptoms. Single doses of THC and CBD differently modulate brain function in areas that process auditory and visual stimuli and relate to induced psychotic symptoms. Neuropsychopharmacology (2011) 36, 1340-1348; doi:10.1038/npp.2011.17; published online 16 March 2011

Cytotoxic and genotoxic effects of two medicinal species of Verbenaceae

Lantana camara L. and Lippia alba (Mill.) N. E. Br. are two important species of Verbenaceae family and are commonly used in folk medicine in many countries of Central and Southern America. The aim of this study was to investigate, for the first time, the cytotoxic and genotoxic effects of aqueous extracts from leaves of both species on Lactuca sativa (lettuce) root tip meristem cells using a cytogenetic approach. Seeds of lettuce were separately treated during 72h with different concentrations of L. camara and L. alba aqueous extracts (5, 10, 20 and 30g/L). The percentage of germination, root development and cellular behavior were analyzed and the results showed that the highest concentration of aqueous extracts reduced the mitotic index, the seeds germination and the root development of lettuce. The extracts also induced chromosome aberrations and cellular death in roots cells of L. sativa. The cytogenotoxicity of L. camara and L. alba extracts was comparatively described.

A randomized controlled trial of homeopathic treatment of weaned piglets in a commercial swine herd

Aim: To evaluate the zootechnic performance and occurrence of diarrhea in piglets in the week post-weaning comparing supplementation with sucrose saline which contained or did not contain added homeopathic medicine. Method. Animals were randomly divided into three groups of 24 piglets each. The control group did not receive any treatment. Another group received sucrose saline, and the third group received sucrose saline with homeopathic medicine added, in the period of zero to seven days post-weaning. The homeopathic treatment consisted of Echinacea angustifolia, Avena sativa, Ignatia amara, Calcarea carbonica, all 6cH. Piglets were weighed daily for weight gain or loss, and observed for diarrhea and feed intake. Results: Animals receiving sucrose saline alone and sucrose saline with homeopathy had less weight loss than control (p = 0.017, p = 0.0001 respectively). There was no statistical difference in relation to overall incidence of diarrhea or food consumption. These data suggest that the supplementation with sucrose saline with added homeopathic medicine in the first seven days post-weaning may be an useful option to reduce weight loss in weaned piglets. Homeopathy (2008) 97, 202-205.