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International Journal of Molecular... Dec 2020β-Endorphins are peptides that exert a wide variety of effects throughout the body. Produced through the cleavage pro-opiomelanocortin (POMC), β-endorphins are the... (Review)
Review
β-Endorphins are peptides that exert a wide variety of effects throughout the body. Produced through the cleavage pro-opiomelanocortin (POMC), β-endorphins are the primarily agonist of mu opioid receptors, which can be found throughout the body, brain, and cells of the immune system that regulate a diverse set of systems. As an agonist of the body's opioid receptors, β-endorphins are most noted for their potent analgesic effects, but they also have their involvement in reward-centric and homeostasis-restoring behaviors, among other effects. These effects have implicated the peptide in psychiatric and neurodegenerative disorders, making it a research target of interest. This review briefly summarizes the basics of endorphin function, goes over the behaviors and regulatory pathways it governs, and examines the variability of β-endorphin levels observed between normal and disease/disorder affected individuals.
Topics: Animals; Behavior; Behavior, Animal; Brain; Energy Metabolism; Humans; Inflammation; Stress, Physiological; beta-Endorphin
PubMed: 33396962
DOI: 10.3390/ijms22010338 -
Pain Sep 2023The efficacy of acupuncture in treating pain diseases has been recognized in clinical practice, and its mechanism of action has been a hot topic in academic acupuncture...
The efficacy of acupuncture in treating pain diseases has been recognized in clinical practice, and its mechanism of action has been a hot topic in academic acupuncture research. Previous basic research on acupuncture analgesia has focused mostly on the nervous system, with few studies addressing the immune system as a potential pathway of acupuncture analgesia. In this study, we investigated the effect of electroacupuncture (EA) on the β-endorphins (β-END) content, END-containing leukocyte type and number, sympathetic neurotransmitter norepinephrine (NE), and chemokine gene expression in inflamed tissues. To induce inflammatory pain, about 200 µL of complete Frester adjuvant (CFA) was injected into the unilateral medial femoral muscle of adult Wistar rats. Electroacupuncture treatment was performed for 3 days beginning on day 4 after CFA injection, with parameters of 2/100 Hz, 2 mA, and 30 minutes per treatment. The weight-bearing experiment and enzyme-linked immunosorbent assay showed that EA treatment significantly relieved spontaneous pain-like behaviors and increased the level of β-END in inflamed tissue. Injection of anti-END antibody in inflamed tissue blocked this analgesic effect. Flow cytometry and immunofluorescence staining revealed that the EA-induced increase in β-END was derived from opioid-containing ICAM-1 + /CD11b + immune cells in inflamed tissue. In addition, EA treatment increased the NE content and expression of β2 adrenergic receptor (ADR-β2) in inflammatory tissues and upregulated Cxcl1 and Cxcl6 gene expression levels. These findings provide new evidence for the peripheral analgesic effect of acupuncture treatment by recruiting β-END-containing ICAM-1 + /CD11b + immune cells and increasing the β-END content at the site of inflammation.
Topics: Rats; Animals; beta-Endorphin; Intercellular Adhesion Molecule-1; Electroacupuncture; Neutrophils; Rats, Wistar; Pain; Analgesics; Acupuncture Analgesia
PubMed: 37027145
DOI: 10.1097/j.pain.0000000000002892 -
Neuroscience Letters Jan 2021We examined the association between endogenous opioid β-endorphin, cancer progression and pain in a transgenic mouse model of breast cancer, with a rat C3(1) simian...
We examined the association between endogenous opioid β-endorphin, cancer progression and pain in a transgenic mouse model of breast cancer, with a rat C3(1) simian virus 40 large tumor antigen fusion gene (C3TAg). C3TAg mice develop ductal epithelial atypia at 8 weeks, progression to intra-epithelial neoplasia at 12 weeks, and invasive carcinoma with palpable tumors at 16 weeks. Consistent with invasive carcinoma at 4 months of age, C3TAg mice demonstrate a significant increase in hyperalgesia compared to younger C3TAg or control FVBN mice without tumors. Our data show that the growing tumor contributes to circulating β-endorphin. As an endogenous ligand of mu opioid receptor, β-endorphin has analgesic activity. Paradoxically, we observed an increase in pain in transgenic breast cancer mice with significantly high circulating and tumor-associated β-endorphin. Increased circulating β-endorphin correlates with increasing tumor burden. β-endorphin induced the activation of mitogenic and survival-promoting signaling pathways, MAPK/ERK 1/2, STAT3 and Akt, observed by us in human MDA-MB-231 cells suggesting a role for β-endorphin in breast cancer progression and associated pain.
Topics: Animals; Biomarkers; Breast Neoplasms; Cancer Pain; Cell Line, Tumor; Disease Progression; Female; Humans; Mice; Mice, Transgenic; beta-Endorphin
PubMed: 33387660
DOI: 10.1016/j.neulet.2020.135601 -
Journal of Affective Disorders Jan 2021Beta-endorphin (BE) has been suggested to play a central role as to why people engage in NSSI. To our knowledge, no study has systematically assessed this potential...
BACKGROUND
Beta-endorphin (BE) has been suggested to play a central role as to why people engage in NSSI. To our knowledge, no study has systematically assessed this potential relationship in adolescents with NSSI.
METHODS
94 adolescents with NSSI (according to DSM-5 criteria) and 35 healthy controls (HC) were enrolled. All participants received heat pain stimulation, with pain threshold and tolerance measured in °C. Plasma BE levels were assessed. Sociodemographic and clinical characteristics were obtained via semi-structured interviews and self-report questionnaires.
RESULTS
Adolescents with NSSI showed increased pain thresholds (t=2.071, p=.040), lower pain intensity (t==2.122, p=.036) and lower plasma BE levels (t==3.182, p=.002) compared to HC. Groups did not differ on pain tolerance (t=0.911, p=.364). Greater pain threshold correlated positively with borderline personality disorder (BPD) symptoms (r=0.182, p=.039), while pain intensity (r=-0.206, p=.033) and BE levels (r=-0.246, p=.007) correlated negatively with depression severity. No significant relationship was found between pain threshold and plasma BE (r=-0.013, p=.882).
LIMITATIONS
Future studies should implement repeated plasma BE measures to assess BE release in association with pain in NSSI. Validity of plasma BE measures compared to central measures should be considered. Assessing the association between pain sensitivity (PS) and BE in a naturalistic setting presents a promising avenue for future research in NSSI.
CONCLUSIONS
Findings support both reduced PS and basal opioid deficiency as independent biological correlates and potential risk-factors for NSSI. Further longitudinal and experimental studies are needed to investigate the role of BE levels and PS as well as their potential association.
Topics: Adolescent; Borderline Personality Disorder; Humans; Pain; Pain Threshold; Plasma; Self-Injurious Behavior; beta-Endorphin
PubMed: 32961416
DOI: 10.1016/j.jad.2020.09.036 -
Archives of Gynecology and Obstetrics Jul 2018To compare the concentrations of beta endorphin in serum and follicular fluid (FF) of PCOS- and non-PCOS women. Secondarily, to investigate associations between beta...
PURPOSE
To compare the concentrations of beta endorphin in serum and follicular fluid (FF) of PCOS- and non-PCOS women. Secondarily, to investigate associations between beta endorphin and other parameters.
METHODS
Fifty-nine women undergoing in vitro fertilization (IVF) were included in the study. Sixteen were stratified to the PCOS group using the Rotterdam criteria. The remaining 43 women served as controls. Follicular fluid was collected during oocyte retrieval and peripheral blood sampling was performed on the same day. Beta endorphin concentrations in serum and follicular fluid, serum levels of insulin, glucose, LH, estradiol and progesterone were measured. Additionally, testosterone was measured before starting the stimulation protocol.
RESULTS
There was no difference in beta endorphin levels between PCOS- and non-PCOS women. The concentration of the peptide was higher in serum than in FF, likely due to collection of FF after ovulation induction and corresponding to the early luteal phase. We found a significant correlation between the number of mature Metaphase II (MII) oocytes retrieved and beta endorphin concentration in FF. In women with biochemical hyperandrogenemia, beta endorphin levels in FF correlated with testosterone levels.
CONCLUSION
Beta Endorphin concentrations in serum and FF do not differ between PCOS- and non PCOS-women undergoing IVF. However, together with sex hormones, beta endorphin might play a key role in oocyte maturation.
Topics: Adult; Female; Follicular Fluid; Humans; Polycystic Ovary Syndrome; Young Adult; beta-Endorphin
PubMed: 29808249
DOI: 10.1007/s00404-018-4793-6 -
Nature Communications Nov 2023Although beta-endorphinergic neurons in the hypothalamic arcuate nucleus (ARC) synthesize beta-endorphin (β-EP) to alleviate nociceptive behaviors, the underlying...
Although beta-endorphinergic neurons in the hypothalamic arcuate nucleus (ARC) synthesize beta-endorphin (β-EP) to alleviate nociceptive behaviors, the underlying regulatory mechanisms remain unknown. Here, we elucidated an epigenetic pathway driven by microRNA regulation of β-EP synthesis in ARC neurons to control neuropathic pain. In pain-injured rats miR-203a-3p was the most highly upregulated miRNA in the ARC. A similar increase was identified in the cerebrospinal fluid of trigeminal neuralgia patients. Mechanistically, we found histone deacetylase 9 was downregulated following nerve injury, which decreased deacetylation of histone H3 lysine-18, facilitating the binding of NR4A2 transcription factor to the miR-203a-3p gene promoter, thereby upregulating miR-203a-3p expression. Further, increased miR-203a-3p was found to maintain neuropathic pain by targeting proprotein convertase 1, an endopeptidase necessary for the cleavage of proopiomelanocortin, the precursor of β-EP. The identified mechanism may provide an avenue for the development of new therapeutic targets for neuropathic pain treatment.
Topics: Animals; Humans; Rats; Arcuate Nucleus of Hypothalamus; beta-Endorphin; Epigenesis, Genetic; MicroRNAs; Neuralgia; Neurons; Rodentia
PubMed: 37945654
DOI: 10.1038/s41467-023-43022-7 -
Anesthesia Progress 1991Beta-endorphin is a peptide with morphine-like effects produced primarily in the anterior lobe of the pituitary gland. After its cleavage from the parent molecule,... (Review)
Review
Beta-endorphin is a peptide with morphine-like effects produced primarily in the anterior lobe of the pituitary gland. After its cleavage from the parent molecule, proopiomelanocortin, beta-endorphin is circulated via the blood stream to interact with specific opioid receptors located throughout the body. The peptide produces analgesia by inhibiting the firing of peripheral somatosensory fibers. It also affects other senses, such as vision, hearing, and smell. Whereas the ability to increase beta-endorphin secretion during times of surgical stress is positively correlated with amelioration of pain, the administration of exogenous opioids, such as fentanyl, reduces plasma beta-endorphin. Decreased beta-endorphin concentrations may play a role in trigeminal neuralgia, migraine headache, and rheumatoid arthritis.
Topics: Humans; Nociceptors; Pain; beta-Endorphin
PubMed: 1814247
DOI: No ID Found -
Disease Markers 2016Background. Allergic rhinitis (AR) significantly impairs the quality of life of the patients; however, a questionnaire alone is an insufficient and subjective measure of...
Background. Allergic rhinitis (AR) significantly impairs the quality of life of the patients; however, a questionnaire alone is an insufficient and subjective measure of this condition. Obtaining an objective clinical assessment of the level of impairment will be valuable for its treatment. β-Endorphin is one of the most important mediators of both mental state and specific immunity. Thus, we investigated the possibility of using β-endorphin as a biomarker for evaluating the impairment level in AR. Methods. This study included 48 patients with AR and 32 healthy volunteers. The serum β-endorphin level was determined by enzyme immunoassay, and the serum-specific IgE and total IgE levels were determined by immunoblot assay. The Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) was used to assess the impairment level in the symptom duration. Results. The β-endorphin concentration was significantly decreased in AR patients compared to the healthy controls (p = 0.000, p < 0.05). There was significant negative correlation between the impairment level and serum β-endorphin level (correlation coefficient: -0.468; p = 0.001; p < 0.05), but there was no association between the serum β-endorphin and total IgE levels (p = 0.947, p > 0.05). Conclusion. β-Endorphin is a systemic biomarker that has the potential to assess the impairment level in AR and may therefore be a novel therapeutic target for the treatment of AR.
Topics: Adolescent; Adult; Aged; Biomarkers; Case-Control Studies; Female; Humans; Male; Middle Aged; Quality of Life; Rhinitis, Allergic; beta-Endorphin
PubMed: 27647946
DOI: 10.1155/2016/2025418 -
Scientific Reports Jul 2023Asthma, a chronic respiratory disease is characterized by airway inflammation, remodelling, airflow limitation and hyperresponsiveness. At present, it is considered as...
Asthma, a chronic respiratory disease is characterized by airway inflammation, remodelling, airflow limitation and hyperresponsiveness. At present, it is considered as an umbrella diagnosis consisting several variable clinical presentations (phenotypes) and distinct pathophysiological mechanisms (endotypes). Recent evidence suggests that oxidative stress participates in airway inflammation and remodelling in chronic asthma. Opioids resembled by group of regulatory peptides have proven to act as an immunomodulator. β-Endorphin a natural and potent endogenous morphine produced in the anterior pituitary gland play role in pain modulation. Therapeutic strategy of many opioids including β-Endorphin as an anti‑inflammatory and antioxidative agent has not been yet explored despite its promising analgesic effects. This is the first study to reveal the role of β-Endorphin in regulating airway inflammation, cellular apoptosis, and oxidative stress via Nrf-2 in an experimental asthmatic model. Asthma was generated in balb/c mice by sensitizing with 1% Toulene Diisocyanate on day 0, 7, 14 and 21 and challenging with 2.5% Toulene Diisocyanate from day 22 to 51 (on every alternate day) through intranasal route. β-Endorphin (5 µg/kg) was administered through the nasal route 1 h prior to sensitization and challenge. The effect of β-Endorphin on pulmonary inflammation and redox status along with parameters of oxidative stress were evaluated. We found that pre-treatment of β-Endorphin significantly reduced inflammatory infiltration in lung tissue and cell counts in bronchoalveolar lavage fluid. Also, pre-treatment of β-Endorphin reduced reactive oxygen species, Myeloperoxidase, Nitric Oxide, Protein and protein carbonylation, Glutathione Reductase, Malondialdehyde, IFN-γ, and TNF-α. Reversely, β-Endorphin significantly increased Superoxide dismutase, Catalase, glutathione, Glutathione-S-Transferase, and activation of NF-E2-related factor 2 (Nrf-2) via Kelch-like ECH-associated protein 1 (Keap1), independent pathway in the lung restoring architectural alveolar and bronchial changes. The present findings reveal the therapeutic potency of β-END in regulating asthma by Keap-1 independent regulation of Nrf-2 activity. The present findings reveal the therapeutic potency of β-Endorphin in regulating asthma.
Topics: Mice; Animals; Analgesics, Opioid; beta-Endorphin; Kelch-Like ECH-Associated Protein 1; Disease Models, Animal; NF-E2-Related Factor 2; Asthma; Oxidative Stress; Inflammation; Bronchoalveolar Lavage Fluid; Glutathione; Apoptosis; Mice, Inbred BALB C
PubMed: 37524754
DOI: 10.1038/s41598-023-38366-5 -
Medical Science Monitor : International... Sep 2020BACKGROUND Increased levels of endogenous opioids have been observed in patients with schizophrenia; however, the influence of these endogenous opioids on the biology of...
BACKGROUND Increased levels of endogenous opioids have been observed in patients with schizophrenia; however, the influence of these endogenous opioids on the biology of schizophrenia remains unclear. The aim of this study was to evaluate the impact of beta-endorphin (BE) on the course of schizophrenia and risk of relapse. MATERIAL AND METHODS The study included 25 patients hospitalized with schizophrenia and 47 controls. Their symptoms were evaluated using Positive and Negative Syndrome Scale (PANSS) and composite index at five points: at the onset of hospitalization; after 4, 6 and 10 weeks of treatment; and after 12 months. ß-endorphin plasma concentrations were assessed in patients at study enrollment and after 6 weeks of treatment. Data regarding rehospitalization during follow-up were also collected. RESULTS Patients had higher BE concentration than controls at study enrollment (P=0.002) and after 6 weeks (P=0.000). BE levels increased during treatment (mean 0.538ng/mL vs. mean 0.624 ng/mL; P=0.007). No correlation was found between BE concentration and PANSS subscale score at any stage of the study. A higher BE level at study enrollment was related to a predominance of negative symptoms after 1 year, measured with composite index (R=-0.404; P=0.045). Patients who were later hospitalized again were significantly more likely to demonstrate an increase in BE levels over 6 weeks (P=0.001). CONCLUSIONS Individuals with schizophrenia demonstrated higher BE concentrations than healthy controls; this tendency was particularly apparent in those affected by negative symptoms. The imbalance in the endogenous opioid system might adversely alter the course of disease and predispose patients to persistence of negative symptoms, despite antipsychotic treatment.
Topics: Adult; Antipsychotic Agents; Female; Follow-Up Studies; Humans; Male; Middle Aged; Recurrence; Schizophrenia; Treatment Outcome; beta-Endorphin
PubMed: 32892205
DOI: 10.12659/MSM.924307