'Oxytocin' for the outwardly oriented: Evidence for interactive effects in placebo responding

Peripheral blood transcriptomic profiling indicates molecular mechanisms commonly regulated by binge-drinking and placebo-effects

Molecular changes associated with alcohol consumption arise from complex interactions between pharmacological effects of alcohol, psychological/placebo context surrounding drinking, and other environmental and biological factors. The goal of this study was to tease apart molecular mechanisms regulated by pharmacological effects of alcohol - particularly at binge-drinking, from underlying placebo effects. Transcriptome-wide RNA-seq analyses were performed on peripheral blood samples collected from healthy heavy social drinkers (N=16) enrolled in a 12-day randomized, double-blind, cross-over human laboratory trial testing three alcohol doses: Placebo, moderate (0.05g/kg (men), 0.04g/kg (women)), and binge (1g/kg (men), 0.9g/kg (women)), administered in three 4-day experiments, separated by minimum of 7-day washout periods. Effects of beverage doses on the normalized gene expression counts were analyzed within each experiment compared to its own baseline using paired-t-tests. Differential expression of genes (DEGs) across experimental sequences in which each beverage dose was administered, as well as responsiveness to regular alcohol compared to placebo (i.e., pharmacological effects), were analyzed using generalized linear mixed-effects models. The 10% False discovery rate-adjusted DEGs varied across experimental sequences in response to all three beverage doses. We identified and validated 22 protein coding DEGs potentially responsive to pharmacological effects of binge and medium doses, of which 11 were selectively responsive to binge dose. Binge-dose significantly impacted the Cytokine-cytokine receptor interaction pathway (KEGG: hsa04060) across all experimental-sequences that it was administered in, and during dose-extending placebo. Medium dose and placebo impacted pathways hsa05322, hsa04613, and hsa05034, in the first two and last experimental sequences, respectively. In summary, our findings add novel, and confirm previously reported data supporting dose-dependent effects of alcohol on molecular mechanisms and suggest that the placebo effects may induce molecular responses within the same pathways regulated by alcohol. Innovative study designs are required to validate molecular correlates of placebo effects underlying drinking.

The Temporal Modulation of Nocebo Hyperalgesia in a Model of Sustained Pain

BACKGROUND

The direction and the magnitude of verbal suggestions have been shown to be strong modulators of nocebo hyperalgesia, while little attention has been given to the role of their temporal content. Here, we investigate whether temporal suggestions modulate the timing of nocebo hyperalgesia in an experimental model of sustained pain.

METHODS

Fifty-one healthy participants were allocated to one of three groups. Participants received an inert cream and were instructed that the agent had either hyperalgesic properties setting in after 5 (Nocebo 5, N5) or 30 (Nocebo 30, N30) minutes from cream application, or hydrating properties (No Expectation Group, NE). Pain was induced by the Cold Pressure Test (CPT) which was repeated before cream application (baseline) and after 10 (Test10) and 35 (Test35) minutes. Changes in pain tolerance and in HR at each test point in respect to baseline were compared between the three groups.

RESULTS

Tolerance change at Test 10 (Δ10) was greater in N5 (MED = -36.8; IQR = 20.9) compared to NE (MED = -5.3; IQR = 22.4; p < 0.001) and N30 (MED = 0.0; IQR = 23.1; p < 0.001), showing that hyperalgesia was only present in the group that expected the effect of the cream to set in early. Tolerance change at Test 35 (Δ35) was greater in N5 (MED = -36.3; IQR = 35.3; p = 0.002) and in N30 (MED = -33.3; IQR = 34.8; p = 0.009) compared to NE, indicating delayed onset of hyperalgesia in N30, and sustained hyperalgesia in N5. No group differences were found for HR.

CONCLUSIONS

Our study demonstrated that temporal expectations shift nocebo response onset in a model of sustained pain.

The placebo and its effects: A psychoneuroendocrinological perspective

Placebos are usually employed deceptively in clinical trials in order to control for non-specific effects. However, since placebos themselves have been found to cause clinically relevant changes and in some cases are indistinguishable from the verum they are tested against, this theoretically inert, but practically effective intervention has become a scientific discipline in its own right. In this review, it is argued that placebos are generic and genuine biopsychosocial interventions and as such are highly interesting candidates for a psychoneuroendocrinological perspective. Yet, despite a considerable conceptual proximity between explanatory models of placebos and their effects with psychoneuroendocrine models and findings, placebos have thus far not been subject to systematic psychoneuroendocrine examination. Consequently, it would be highly interesting and informative to make placebos the target of psychoneuroendocrine scrutiny.

The neurobiology of placebo effects in sports: EEG frontal alpha asymmetry increases in response to a placebo ergogenic aid

The performance enhancing (ergogenic) placebo effect is elicited by an inert treatment and caused by positive affective appraisal of effort perception. Frontal alpha asymmetry (FAA) is a neurobiological correlate of positive affect. This study investigates, whether receiving an ergogenic placebo increases FAA and whether scores on the behavioral inhibition and activation system (BIS/BAS) scales affect this increase in FAA. Nineteen competitive male cyclists (37.26 ± 9.82 years) performed two maximum effort time trials. The first served as baseline for the second intervention time trial, where athletes received a placebo ergogenic aid or no treatment. We recorded FAA using EEG throughout all time trials and assessed BIS/BAS by questionnaire. There was a significant difference in change from baseline to intervention time trial in FAA during cycling in response to the placebo ergogenic aid compared to the control group. BIS, the BAS subscale Drive and the BAS-BIS difference score significantly co-varied with the change in FAA from baseline to intervention time trial in response to the placebo ergogenic aid. Administering a placebo ergogenic aid significantly influenced FAA during maximum effort cycling. Those athletes with a more pronounced goal seeking persistence and an overall dominance of the BAS over the BIS showed a significantly greater increase in FAA in response to a placebo ergogenic aid. A more pronounced BIS, however, seems to antagonize the increase in FAA associated with the ergogenic placebo response.

Effects and Components of Placebos with a Psychological Treatment Rationale - Three Randomized-Controlled Studies

In recent years, placebos have evolved from a mean to control for 'therapeutic chaff' to something that has clinically relevant effects with biological underpinning and that is considered to have clinical as well as scientific potential. However, the wealth of scientific placebo research is conceptualized in a biomedical context, i.e. based on placebos provided with a biomedical treatment rationale, whereas little is known about effects and mechanisms of placebos provided with a psychological treatment rationale. This has important repercussions not only on placebo research, but also on attempts to establish specificity of psychological interventions, such as psychotherapy. Therefore, we set out to assess the effects and possible components of placebos provided with a psychological treatment rationale in three experiments on healthy subjects. We show that placebos provided with a psychological treatment rationale are effective in short- as well as mid-term, but only when provided by a trustworthy, friendly and empathetic experimenter. These findings indicate that placebos are effective outside the medical context and thus need be controlled for in non-medical trials. Furthermore, it highlights and confirms the importance of a plausible psychological treatment rationale in the context of a therapeutic alliance for psychological interventions, such as psychotherapy.

A Randomized Controlled Study of the Yi Qi Gu Biao Pill in the Treatment of Frequent Exacerbator Phenotype in Chronic Obstructive Pulmonary Disease (Lung and Spleen Qi Deficiency Syndrome)

Objective

To evaluate the efficacy and safety of Yi Qi Gu Biao (YQGB) pill in treating frequent exacerbator phenotype in chronic obstructive pulmonary disease (lung and spleen qi deficiency syndrome) (FEPCOPD).

Methods

This prospective, randomized, double-blind, controlled study assessed 112 cases (64 included) of FEPCOPD treated at the outpatient department in our hospital in January–August 2016. The patients were randomly divided into YQGB and placebo (Pb) and treated for three months. Lung function, CAT, mMRC, and TCM symptom scores (TCMs) were observed.

Results

Compared with Pb, YQGB showed decreased wheezing symptom scores (WSs) and TCMs at one month and decreased CAT and TCMs at three months. From one to three months, CAT, cough, sputum, WSs, and TCMs in YQGB were lower than pretreatment values. But in Pb, CAT was lower than pretreatment values after one month; CAT, sputum, and TCMs were lower than pretreatment values after two months; CAT, cough, sputum, WSs, and TCMs were lower than pretreatment values after three months.

Conclusion

Yi Qi Gu Biao pill can improve wheezing, health status, and TCMs in FEPCOPD and also can shorten the durations of cough, sputum, and wheezing. This trial is registered in the Clinical Trials Registry of China: ChiCTR-IOR-15007542 (on 8 December 2015).