Faculty Opinions recommendation of Interface of physical and emotional stress regulation through the endogenous opioid system and mu-opioid receptors.

Background: Activation of the immune-inflammatory response system (IRS) and the compensatory immune-regulatory system (CIRS) play a key role in SCZ and treatment resistant SCZ. There are only few data on immune and endogenous opioid system (EOS) interactions in SCZ and treatment resistant SCZ.Aim of the study: We examined serum β-endorphin, endomorphin-2 (EM2), mu-opioid (MOR) and kappa-opioid (KOR) receptors, and interleukin (IL)-6 and IL-10 in 60 non responders to treatment (NRTT), 55 partial RTT (PRTT) and 43 normal controls.Results: Serum EM2, KOR, MOR, IL-6 and IL-10 were significantly increased in SCZ as compared with controls. β-endorphin, EM2, MOR and IL-6 were significantly higher in NRTT than in PRTT. There were significant correlations between IL-6, on the one hand, and β-endorphin, EM2, KOR, and MOR, on the other, while IL-10 was significantly correlated with MOR only. A large part of the variance in negative symptoms, psychosis, hostility, excitation, mannerism, psychomotor retardation and formal thought disorders was explained by the combined effects of EM2 and MOR with or without IL-6 while increased KOR was significantly associated with all symptom dimensions. Increased MOR, KOR, EM2 and IL-6 were also associated with neurocognitive impairments including in episodic, semantic and working memory and executive functions.Conclusion: The EOS contributes to SCZ symptomatology, neurocognitive impairments and a non-response to treatment. In SCZ, EOS peptides/receptors may exert CIRS functions, whereas increased KOR levels may contribute to the pathophysiology of SCZ and EM2 and KOR to a non-response to treatment.

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Faculty Opinions recommendation of Placebo effects mediated by endogenous opioid activity on mu-opioid receptors.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.11637.469119 ◽

2006 ◽

Author(s):

Arne May

Keyword(s):

Opioid Receptors ◽

Placebo Effects ◽

Mu Opioid Receptors ◽

Endogenous Opioid ◽

Opioid Activity ◽

Mu Opioid

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Borderline personality disorder - a dysregulation of the endogenous opioid system?

European Psychiatry ◽

10.1016/s0924-9338(11)72713-4 ◽

2011 ◽

Vol 26 (S2) ◽

pp. 1008-1008

Author(s):

B. Bandelow ◽

C. Schmahl ◽

P. Falkai ◽

D. Wedekind

Keyword(s):

Borderline Personality Disorder ◽

Personality Disorder ◽

Opioid Receptors ◽

Borderline Personality ◽

Endogenous Opioids ◽

The Body ◽

Opioid System ◽

Endogenous Opioid System ◽

Endogenous Opioid ◽

Self Injury

The neurobiology of borderline personality disorder (BPD) remains unclear. Dysfunctions of several neurobiological systems have been discussed, including serotoninergic, dopaminergic, and other neurotransmitter systems.Here we present a theory that alterations in the sensitivity of opioid receptors or the availability of endogenous opioids constitute part of the underlying pathophysiology of BPD.1 The alarming symptoms and self-destructive behaviors of the affected patients may be explained by uncontrollable and unconscious attempts to stimulate their endogenous opioid system (EOS) and the dopaminergic reward system, regardless of the possible harmful consequences. Neurobiological findings that support this hypothesis are reviewed: Frantic efforts to avoid abandonment, frequent and risky sexual contacts, and attention-seeking behavior may be explained by attempts to make use of the rewarding effects of human attachment mediated by the EOS. Anhedonia and feelings of emptiness may be an expression of reduced activity of the EOS. Patients with BPD tend to abuse substances that target μ-opioid receptors. Self-injury, food-restriction, aggressive behavior, and sensation-seeking may be interpreted as a desperate attempt to artificially set the body to “survival mode”, in order to mobilize the last reserves of the EOS. BPD-associated symptoms, such as substance abuse, anorexia, self-injury, depersonalization, and sexual overstimulation, can be treated successfully with μ-opioid receptor antagonists.An understanding of the neurobiology of BPD may help in developing new treatments for patients with this severe disorder.

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