Serum β-endorphin levels are associated with addiction to suicidal behavior: A pilot study

Progesterone receptor distribution in the human hypothalamus and its association with suicide

The human hypothalamus modulates mental health by balancing interactions between hormonal fluctuations and stress responses. Stress-induced progesterone release activates progesterone receptors (PR) in the human brain and triggers alterations in neuropeptides/neurotransmitters. As recent epidemiological studies have associated peripheral progesterone levels with suicide risks in humans, we mapped PR distribution in the human hypothalamus in relation to age and sex and characterized its (co-) expression in specific cell types. The infundibular nucleus (INF) appeared to be the primary hypothalamic structure via which progesterone modulates stress-related neural circuitry. An elevation of the number of pro-opiomelanocortin+ (POMC, an endogenous opioid precursor) neurons in the INF, which was due to a high proportion of POMC+ neurons that co-expressed PR, was related to suicide in patients with mood disorders (MD). MD donors who died of legal euthanasia were for the first time enrolled in a postmortem study to investigate the molecular signatures related to fatal suicidal ideations. They had a higher proportion of PR co-expressing POMC+ neurons than MD patients who died naturally. This indicates that the onset of endogenous opioid activation in MD with suicide tendency may be progesterone-associated. Our findings may have implications for users of progesterone-enriched contraceptives who also have MD and suicidal tendencies.

Assessment of Plasma-Endogenous Opioid Neuropeptide Levels and Psychometric Properties of Non-Suicidal Self-Injury in Adolescents

OBJECTIVE

Non-suicidal self-injury (NSSI) is one of the most common mental health problems and growing public-health issues, coupled with a significant population-level burden among adolescents in both developed and developing countries. We aimed to assess the role of endogenous opioid system-emotion regulation circuitry in NSSI through measurement of plasma beta-endorphin (β-EP), met-enkephalin (MENK) levels, and determination of psychometric features of Turkish adolescent subjects.

METHOD

In this research, we measured plasma β-EP and MENK levels of 49 adolescents with NSSI and 39 control subjects without NSSI between the ages of 12-18 years. All adolescent subjects were observed in the outpatient clinic, and their clinical and sociodemographic characteristics were examined. All subjects were assessed using the Brief Symptom Inventory (BSI) and Inventory of Statements About Self Injury (ISAS).

RESULTS

Plasma β-EP levels were statistically lower in adolescents with NSSI than control group, whereas there was no statistically significant difference in MENK levels. β-EP levels showed a negative correlation with depression severity. The data obtained from BSI and ISAS were not found to be associated with both β-EP and MENK levels, while subscale scores exhibited versatile correlations.

CONCLUSION

Our findings supported the salient role of β-EP in NSSI behavior. Also, decreased plasma β-EP could be assessed as a reliable indicator for NSSI. However, it is possible that measurement of basal plasma levels of neuropeptides might also bring many confounders and could cause bias. Therefore, repeated measurements of plasma-endogenous opioid neuropeptides in a time-dependent manner-concomitant to engage of NSSI behavior-might give more reliable results.

Biosignature of self-injury behaviors in adolescence: Role of β-endorphin in an acute inpatient unit

Self-injurious behavior (SIB) (either non-suicidal self-injury, NSSI; or suicide attempts, SA) is a common reason for adolescent psychiatric emergency hospitalizations. Altered basal serum β-endorphin (BE) levels have been reported in adults with a history of SIB, but information is lacking in adolescents. We analyzed the psychoclinical profile and serum BE level of 39 adolescents admitted to the acute unit at a hospital in Spain due to SIB. The Mean (SD) serum BE level was high (190.53 ± 74.83). Regarding time sequence, the onset age of NSSI and SA were related (p < 0.001). The older the onset age of NSSI, the shorter the transition between NSSI and the onset of SA behavior (p = 0.05), but this difference does not lead the variation of BE (p = 0.81). Patients diagnosed with depression had lower serum BE levels than adolescents with other diagnoses (p = 0.03). Although adolescents who seem to be addicted to SIB had higher levels of BE, this finding was not statistically significant. The relationship between serum BE levels and SIB in adolescents requires further investigation.

Non-Suicidal Self-Injury: An Observational Study in a Sample of Adolescents and Young Adults

Non-Suicidal Self-Injury (NSSI) is the self-inflicted destruction of body tissues without suicidal intent with a prevalence of 1.5% to 6.7% in the youth population. At present, it is not clear which emotional and behavioral components are specifically associated with it. Therefore, we studied NSSI in a clinical sample of youth using the Ottawa Self-injury Inventory and the Barratt Impulsiveness Scale 11. The Mann-Whitney test was used to compare the numerical responses provided to the tests. We found 54 patients with NSSI, with a mean age of 17 years. Scores were analyzed in the total sample and in four subgroups. In the total sample, Internal Emotion and External Emotion Regulation, Craving, Non-Planning and Total Impulsivity were significantly associated with NSSI. There were statistically significant differences in Craving between patients with multiple NSSI episodes, suicide attempts and multiple injury modes and patients of other corresponding subgroups, in Internal Emotion Regulation, Sensation Seeking and Motor Impulsivity between NSSI patients with suicide attempts and no suicide attempts, and in Cognitive Impulsivity between NSSI patients with multiple injury modes and one injury mode. It is necessary to carefully evaluate the components underlying NSSI in order to activate personalized treatment options.