Epistatic effects between variants of kappa-opioid receptor gene and A118G of mu-opioid receptor gene increase susceptibility to addiction in Indian population

Author(s):  
Deepak Kumar ◽  
Japashish Chakraborty ◽  
Sumantra Das
Author(s):  
Huiqun Wang ◽  
Danni Cao ◽  
James C Gillespie ◽  
Rolando E Mendez ◽  
Dana E Selley ◽  
...  

The modulation and selectivity mechanisms of seven mixed-action kappa opioid receptor (KOR)/mu opioid receptor (MOR) bitopic modulators were explored. Molecular modeling results indicated that the ‘message’ moiety of seven bitopic modulators shared the same binding mode with the orthosteric site of the KOR and MOR, whereas the ‘address’ moiety bound with different subdomains of the allosteric site of the KOR and MOR. The ‘address’ moiety of seven bitopic modulators bound to different subdomains of the allosteric site of the KOR and MOR may exhibit distinguishable allosteric modulations to the binding affinity and/or efficacy of the ‘message’ moiety. Moreover, the 3-hydroxy group on the phenolic moiety of the seven bitopic modulators induced selectivity to the KOR over the MOR.


CNS Spectrums ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 282-283
Author(s):  
Dev Patel ◽  
Ishandeep Gandhi ◽  
Faisal Malek ◽  
Camille Olechowski ◽  
Alan R. Hirsch

Abstract:Introduction:Choreaform movements provoked by opiates is an infrequent adverse event. Buprenorphine induction of chorea has not heretofore been described. Such a case is presented.METHOD:Case Study: A 38-year-old female presented with a decade long history of alcohol, cocaine, benzodiazepine, and heroin abuse. The patient was insufflating 1.5 grams of heroin daily. On presentation, she was actively withdrawing, scoring 17 on the Clinical Opioid Withdrawal Scale. Urine toxicology screening was positive for opiates, cocaine, and cannabinoids. Buprenorphine 4 mg sublingual was initiated. Within one hour, she observed, “My legs were moving uncontrollably as if I was a marionette.” These dance-like movements were isolated to both legs and gradually resolved after discontinuation of buprenorphine: most of the movements manifested in the first 8 hours, and dissipated over the next 2 days. She did have similar movements after treatment with quetiapine during a previous hospitalization, years earlier.RESULTS:Abnormalities in physical examination: General: goiter, bilateral palmar erythema. Neurological examination: Cranial Nerve (CN) Examination: CN I: Alcohol Sniff Test: 2 (anosmia). Motor Examination: Drift testing: mild right pronator drift. Reflexes: 3+ bilateral lower extremities. Neuropsychiatric Examination: Clock Drawing Test: 3 (abnormal). Animal Fluency Test: 18 (normal). Go-No-Go Test 6/6 (normal).DISCUSSION:Buprenorphine induced chorea could be a result of partial mu-opioid agonism, or kappa and delta receptor antagonism (Burke, 2018; Cowan, 1977). Mu-opioid receptor activation causes increased dopamine turnover in the nigrostriatum, which is responsible for locomotor sensitization (Campos-Jurado, 2017). With the addition of mu-opioid receptor modulation of dopamine release, kappa-opioid receptor alters various neurotransmitters in the basal ganglia, potentiating hyperkinetic movements. Buprenorphine’s choreiformogenic action may be due to kappa-opioid receptors ability to augment neurotransmission in the striatum (Escobar, 2017; Bonnet, 1998). The combination of simultaneous activity of these three opioid receptors may cause chorea, since they act to modulate dopamine, glutamate, and GABA in the direct and indirect pathways within the basal ganglia (Abin, 1989; Cui, 2013; Allouche, 2014; Trifilieff, 2013). This patient’s history of heroin and cocaine use may have caused supersensitization of dopamine receptors (Memo, 1981), provoking hyperkinesia. Involvement of substance-induced sensitization with concurrent kappa-opioid receptor neurotransmitter augmentation in direct and indirect pathways in the basal ganglia may have primed our patient to the development of chorea after buprenorphine administration. Further investigation for the presence of extrapyramidal movements in those undergoing buprenorphine treatment is warranted.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Alan M. Daniel ◽  
Brenda G. Rushing ◽  
Karla Y. Tapia Menchaca

AbstractUnderstanding the emotional reaction to loss, or frustration, is a critical problem for the field of mental health. Animal models of loss have pointed to the opioid system as a nexus of frustration, physical pain, and substance abuse. However, few attempts have been made to connect the results of animal models of loss to human behavior. Allelic differences in the human mu opioid receptor gene, notably the A118G single nucleotide polymorphism, have been linked to individual differences in pain sensitivity, depressive symptoms, and reward processing. The present study explored the relationship between A118G and behavior in two frustrating tasks in humans. Results showed that carriers of the mutant G-allele were slower to recover behavior following a reward downshift and abandoned a frustrating task earlier than those without the mutation. Additionally, G-carriers were more sensitive to physical pain. These results highlight the overlap between frustration and pain, and suggest that genetic variation in opioid tone may contribute to individual differences in vulnerability and resilience following emotional disturbances.


Neuroscience ◽  
2008 ◽  
Vol 151 (4) ◽  
pp. 1034-1041 ◽  
Author(s):  
S.W. Park ◽  
Y. He ◽  
S.G. Ha ◽  
H.H. Loh ◽  
L.-N. Wei

2008 ◽  
Vol 109 (3) ◽  
pp. 520-526 ◽  
Author(s):  
Alex T. Sia ◽  
Yvonne Lim ◽  
Eileen C. P. Lim ◽  
Rachelle W. C. Goh ◽  
Hai Yang Law ◽  
...  

Background Previous studies have shown that genetic variability at position 118 of the human mu-opioid receptor gene altered patients' response to intravenous morphine. The purpose of this study was to investigate whether this polymorphism contributes to the variability in response to morphine for postcesarean analgesia. Methods After investigators obtained informed consent, 588 healthy women received 0.1 mg intrathecal morphine for postcesarean analgesia. Their blood samples were genotyped for the A118G polymorphism-A118 homozygous (AA), heterozygous (AG), or homozygous for the G allele (GG). Pain scores, the severity of nausea and vomiting, the incidence of pruritus, and the total self-administered intravenous morphine were recorded for the first 24 postoperative hours. Results Two hundred seventy women (46%) were AA, 234 (40%) were AG, and 82 (14%) were GG. The 24-h self-administered intravenous morphine consumption was lowest in the AA group (P = 0.001; mean, 5.9; 95% confidence interval, 5.1-6.8) versus the AG (8.0; 6.9-9.1) and GG groups (9.4; 7.3-11.5). Pain scores were lowest in the AA group and highest in the GG group, with a statistically significant difference detected between AA, AG, and GG (P = 0.049). Total morphine consumption was also influenced by patients' age and paying status. AA group was associated with the highest incidence of nausea (26 of 272 [9.6%]; P = 0.02) versus the other two groups (13 of 234 [5.6%] and 1 of 82 [1.2%] for AG and GG, respectively). Conclusion Genetic variation at position 118 of the mu-opioid receptor is associated with interindividual differences in pain scores, self-administered intravenous morphine, and the incidence of nausea postoperatively.


2021 ◽  
Author(s):  
Nicholas S. Akins ◽  
Nisha Mishra ◽  
Hannah M. Harris ◽  
Narendar Dudhipala ◽  
Seong Jong Kim ◽  
...  

Analgesia is commonly mediated through the mu or kappa opioid receptor agonism. Unfortunately, selective mu or kappa receptor agonists often cause harmful side effects. Recently, ligands exhibiting dual agonism to the opioid receptors, such as to mu and kappa, or to mu and delta, have been suggested to temper undesirable adverse effects while retaining analgesic activity. Herein we report an introduction of various 6,5-fused rings to C2 of the salvinorin scaffold <i>via</i> an ester linker. <i>In vitro</i> studies showed that some of these compounds have dual agonism on kappa and mu opioid receptors, while some have triple agonism on kappa, mu, and delta. <i>In vivo </i>studies on the lead dual kappa and mu opioid receptor agonist, compound <b>10</b>, showed that it<b> </b>produced analgesic activity while avoiding anxiogenic effects in murine models, thus providing further strong evidence for the therapeutic advantages of dual opioid receptor agonists over selective opioid receptor agonists.


Sign in / Sign up

Export Citation Format

Share Document