Another approach was chosen by Aviello et al. 43 They used the carcinogen azoxymethane to induce colon cancer in mice. Treatment occurred using IP injections of 1 or 5 mg/kg CBD, three times a week for 3 weeks (including 1 week before carcinogen administration). After 3 months, the number of aberrant crypt foci, polyps, and tumors was analyzed. The high CBD concentration led to a significant decrease in polyps and a return to near-normal levels of phosphorylated Akt (elevation caused by the carcinogen). 42 No adverse effects were mentioned in the described study. 43
Forty-eight participants received subanxiolytic levels (32 mg) of CBD, either before or after the extinction phase in a double-blind, placebo-controlled design of a Pavlovian fear-conditioning experiment (recall with conditioned stimulus and context after 48 h and exposure to unconditioned stimulus after reinstatement). Skin conductance (=autonomic response to conditioning) and shock expectancy measures (=explicit aspects) of conditioned responding were recorded throughout. Among other scales, the Mood Rating Scale (MRS) and the Bond and Bodily Symptoms Scale were used to assess anxiety, current mood, and physical symptoms. “CBD given postextinction (active after consolidation phase) enhanced consolidation of extinction learning as assessed by shock expectancy.” Apart from the extinction-enhancing effects of CBD in human aversive conditioned memory, CBD showed a trend toward some protection against reinstatement of contextual memory. No side/adverse effects were reported. 53
Acute Clinical Data
Some studies indicate that under certain circumstances, CBD acute anxiolytic effects in rats were reversed after repeated 14-day administration of CBD. 2 However, this finding might depend on the used animal model of anxiety or depression. This is supported by a study, where CBD was administered in an acute and “chronic” (2 weeks) regimen, which measured anxiolytic/antidepressant effects, using behavioral and operative models (OBX=olfactory bulbectomy as model for depression). 18 The only observed side effects were reduced sucrose preference, reduced food consumption and body weight in the nonoperated animals treated with CBD (50 mg/kg). Nonetheless, the behavioral tests (for OBX-induced hyperactivity and anhedonia related to depression and open field test for anxiety) in the CBD-treated OBX animals showed an improved emotional response. Using microdialysis, the researchers could also show elevated 5-HT and glutamate levels in the prefrontal cortex of OBX animals only. This area was previously described to be involved in maladaptive behavioral regulation in depressed patients and is a feature of the OBX animal model of depression. The fact that serotonin levels were only elevated in the OBX mice is similar to CBD differential action under physiological and pathological conditions.
In addition, it is possible that CBD targets differ between humans and animals. Therefore, the same blood concentration might still lead to different effects. Even if the targets, to which CBD binds, are the same in both studied animals and humans, for example, the affinity or duration of CBD binding to its targets might differ and consequently alter its effects.
Various studies on CBD and psychosis have been conducted. 20 For instance, an animal model of psychosis can be created in mice by using the NMDAR antagonist MK-801. The behavioral changes (tested with the prepulse inhibition [PPI] test) were concomitant with decreased mRNA expression of the NMDAR GluN1 subunit gene (GRN1) in the hippocampus, decreased parvalbumin expression (=a calcium-binding protein expressed in a subclass of GABAergic interneurons), and higher FosB/ΔFosB expression (=markers for neuronal activity). After 6 days of MK-801 treatment, various CBD doses were injected intraperitoneally (15, 30, 60 mg/kg) for 22 days. The two higher CBD doses had beneficial effects comparable to the atypical antipsychotic drug clozapine and also attenuated the MK-801 effects on the three markers mentioned above. The publication did not record any side effects. 21
Evaluation of a Reiki Program for Healthcare Workers Negatively Impacted by the Pandemic
Women veterans with PTSD related to MST were recruited from two VA Medical Centers. We used virtual means for processes of informed consent, enrollment, data collection, and intervention facilitation. Participants were randomized to 10 weekly sessions of yoga or 12 weekly sessions of CPT. Encrypted email, phone, HIPAA-compliant REDCap, Zoom Video Teleconferencing, and VA Video Connect were used to accommodate in-person restrictions while maintaining confidentiality. Portable electrocardiogram machines, heart rate variability monitors, and finger-prick dried blood spot collection were used in conjunction with virtual staff-assistance to guide participants through self-administered collection of psychophysiological data. Data were collected at baseline, during the intervention, and at two follow-up timepoints.
Mattingly, Holly: P10.01
Liu, Xuehan: P06.09
1 Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
4 US Veterans Health Administration, Washington, District of Columbia
3 Health Equity Research Laboratory, Cambridge Health Alliance, Cambridge, Massachusetts