Health(care) in the Crisis: Reflections in Science and Society on Opioid Addiction

Aniquinazoline B, a Fungal Natural Product, Activates the μ-Opioid Receptor

The development of new μ-opioid receptor (MOR) agonists without the undesirable side effects, such as addiction or respiratory depression, has been a difficult challenge over the years. In the search for new compounds, we screened our chemical database of over 40.000 substances and further assessed the best 100 through molecular docking. We selected the top 10 compounds and evaluated them for their biological activity and potential to influence cyclic adenosine monophosphate (cAMP) levels. From the tested compounds, compound 7, called aniquinazoline B, belonging to the quinazolinone alkaloids class and isolated from the marine fungus Aspergillus nidulans, showed promising results, by inhibiting cAMP levels and in vitro binding to MOR, verified through microscale thermophoresis. Transcriptomic data investigation profiled the genes affected by compound 7 and discovered activation of different pathways compared to opioids. The western blot analysis revealed compound 7 as a balanced ligand, activating both p-ERK1/2 and β-arrestin1/2 pathways, showing this is a favorable candidate to be further tested.

Examining Racial/Ethnic Differences in Patterns of Opioid Prescribing: Results from an Urban Safety-Net Healthcare System

Prescription opioids still account for a large proportion of overdose deaths and contribute to opioid use dependence (OUD). Studies earlier in the epidemic suggest clinicians were less likely to prescribe opioids to racial/ethnic minorities. As OUD-related deaths have increased disproportionately amongst minority populations, it is essential to understand racial/ethnic differences in opioid prescribing patterns to inform culturally sensitive mitigation efforts. The purpose of this study is to estimate racial/ethnic differences in opioid medication use among patients prescribed opioids. Using electronic health records and a retrospective cohort study design, we estimated multivariable hazard models and generalized linear models, assessing racial/ethnic differences in OUD diagnosis, number of opioid prescriptions, receiving only one opioid prescription, and receiving ≥18 opioid prescriptions. Study population (N=22,201) consisted of adult patients (≥18years), with ≥3 primary care visits (ensuring healthcare system linkage), ≥1 opioid prescription, who did not have an OUD diagnoses prior to the first opioid prescription during the 32-month study period. Relative to racial/ethnic minority patients, White patients, in both unadjusted and adjusted analyses, had a greater number of opioid prescriptions filled, a higher proportion received ≥18 opioid prescriptions, and a greater hazard of having an OUD diagnosis subsequent to receiving an opioid prescription (all groups p<0.001). Although opioid prescribing rates have declined nationally, our findings suggest White patients still experience a high volume of opioid prescriptions and greater risk of OUD diagnosis. Racial/ethnic minorities are less likely to receive follow-up pain medications, which may signal low care quality. Identifying provider bias in pain management of racial/ethnic minorities could inform interventions seeking balance between adequate pain treatment and risk of opioid misuse/abuse.

[Narcotic Use under Probation and Parole Supervision - A longitudinal Study of Risk-group-specific Recidivism under Abstinence Conditions]

STUDY OBJECTIVE

The aim of this long-term study was to record substance-specific prevalences of illegal use of narcotics despite court-imposed abstinence requirements.

METHODS

Urine assays were obtained by a public health department on the basis of administrative assistance for the probation department of a district court. The individual and valid allocation of these urine samples was ensured using a proven marker system. After postal dispatch, laboratory chemical analyses for narcotics residues were carried out in an external laboratory via enzyme immunoassay and validation by mass spectrography in the case of positive narcotics results. On the basis of all available routine data, a pooled data set covering a total of fourteen consecutive calendar years (2006-2019) was generated digitally and evaluated anonymously.

RESULTS

From a total of 380 subjects (female: 13% versus male: 87%; average age: 30.4 years), 13,500 individual narcotic substance analyses from 2,941 urine samples were available. In 2.7% of all individual analyses, at least one of eight potential narcotic substances was detected, whereby the highest overall prevalences in the sense of a relapse were found for cannabis with 3.7% and for opiates with 2.4%. In contrast, there were almost no residues for barbiturates and LSD and no positive evidence for buprenorphine and PCP. As expected, most relapses in all narcotics groups were found in the age groups from 18 to 35 years. Strikingly, more women than men violated the court abstinence order with amphetamines, while relapses with the other seven narcotics groups occurred predominantly among men. In the course of the entire observation period, the most marked fluctuations in relapse rates were found for cannabis, opiates and cocaine.

CONCLUSION

The use of narcotic substances during probation and parole supervision does not appear to be a rare occurrence and has received little professional attention. Increased attention to this group-specific recidivism and more studies on this topic should help reduce this deficit.

The roles of ubiquitin-proteasome system and regulator of G protein signaling 4 in behavioral sensitization induced by a single morphine exposure

AIMS

Opioid addiction is a major public health issue, yet its underlying mechanism is still unknown. The aim of this study was to explore the roles of ubiquitin-proteasome system (UPS) and regulator of G protein signaling 4 (RGS4) in morphine-induced behavioral sensitization, a well-recognized animal model of opioid addiction.

METHODS

We explored the characteristics of RGS4 protein expression and polyubiquitination in the development of behavioral sensitization induced by a single morphine exposure in rats, and the effect of a selective proteasome inhibitor, lactacystin (LAC), on behavioral sensitization.

RESULTS

Polyubiquitination expression was increased in time-dependent and dose-related fashions during the development of behavioral sensitization, while RGS4 protein expression was not significantly changed during this phase. Stereotaxic administration of LAC into nucleus accumbens (NAc) core inhibited the establishment of behavioral sensitization.

CONCLUSION

UPS in NAc core is positively involved in behavioral sensitization induced by a single morphine exposure in rats. Polyubiquitination was observed during the development phase of behavioral sensitization, while RGS4 protein expression was not significantly changed, indicating that other members of RGS family might be substrate proteins in UPS-mediated behavioral sensitization.

Systems and Circuits Linking Chronic Pain and Circadian Rhythms

Research over the last 20 years regarding the link between circadian rhythms and chronic pain pathology has suggested interconnected mechanisms that are not fully understood. Strong evidence for a bidirectional relationship between circadian function and pain has been revealed through inflammatory and immune studies as well as neuropathic ones. However, one limitation of many of these studies is a focus on only a few molecules or cell types, often within only one region of the brain or spinal cord, rather than systems-level interactions. To address this, our review will examine the circadian system as a whole, from the intracellular genetic machinery that controls its timing mechanism to its input and output circuits, and how chronic pain, whether inflammatory or neuropathic, may mediate or be driven by changes in these processes. We will investigate how rhythms of circadian clock gene expression and behavior, immune cells, cytokines, chemokines, intracellular signaling, and glial cells affect and are affected by chronic pain in animal models and human pathologies. We will also discuss key areas in both circadian rhythms and chronic pain that are sexually dimorphic. Understanding the overlapping mechanisms and complex interplay between pain and circadian mediators, the various nuclei they affect, and how they differ between sexes, will be crucial to move forward in developing treatments for chronic pain and for determining how and when they will achieve their maximum efficacy.

Can eastern wisdom resolve western epidemics? Traditional Chinese medicine therapies and the opioid crisis

The widespread use of opioids to treat chronic pain led to a nation-wide crisis in the United States. Tens of thousands of deaths annually occur mainly due to respiratory depression, the most dangerous side effect of opioids. Non-opioid drugs and non-pharmacological treatments without addictive potential are urgently required. Traditional Chinese medicine (TCM) is based on a completely different medical theory than academic Western medicine. The scientific basis of acupuncture and herbal treatments as main TCM practices has been considerably improved during the past two decades, and large meta-analyses with thousands of patients provide evidence for their efficacy. Furthermore, opinion leaders in the United States favor non-pharmacological techniques including TCM for pain management to fight the opioid crisis. We advocate TCM as therapeutic option without addictive potential and without life-threatening side effects (e.g., respiratory depression) to treat chronic pain patients suffering from opioid misuse. The evidence suggests that: (1) opioid misuse cannot be satisfactorily managed with standard medication; (2) opinion leaders in the United States favor to consider non-opioid and non-pharmacological treatment strategies including those from TCM to treat acute and chronic pain conditions; (3) large meta-analyses provide scientific evidence for the clinical activity of acupuncture and herbal TCM remedies in the treatment of chronic pain. Future clinical trials should demonstrate the safety of TCM treatments if combined with Western medical practices to exclude negative interactions between both modalities.