The effects of opioids and opioid analogs on animal and human endocrine systems

Restoring function to inactivating G protein-coupled receptor variants in the hypothalamic-pituitary-gonadal axis1

G protein-coupled receptors (GPCRs) are central to the functioning of the hypothalamic-pituitary-gonadal axis (HPG axis) and include the rhodopsin-like GPCR family members, neurokinin 3 receptor, kappa-opioid receptor, kisspeptin 1 receptor, gonadotropin-releasing hormone receptor, and the gonadotropin receptors, luteinizing hormone/choriogonadotropin receptor and follicle-stimulating hormone receptor. Unsurprisingly, inactivating variants of these receptors have been implicated in a spectrum of reproductive phenotypes, including failure to undergo puberty, and infertility. Clinical induction of puberty in patients harbouring such variants is possible, but restoration of fertility is not always a realisable outcome, particularly for those patients suffering from primary hypogonadism. Thus, novel pharmaceuticals and/or a fundamental change in approach to treating these patients are required. The increasing wealth of data describing the effects of coding-region genetic variants on GPCR function has highlighted that the majority appear to be dysfunctional as a result of misfolding of the encoded receptor protein, which, in turn, results in impaired receptor trafficking through the secretory pathway to the cell surface. As such, these intracellularly retained receptors may be amenable to 'rescue' using a pharmacological chaperone (PC)-based approach. PCs are small, cell permeant molecules hypothesised to interact with misfolded intracellularly retained proteins, stabilising their folding and promoting their trafficking through the secretory pathway. In support of the use of this approach as a viable therapeutic option, it has been observed that many rescued variant GPCRs retain at least a degree of functionality when 'rescued' to the cell surface. In this review, we examine the GPCR PC research landscape, focussing on the rescue of inactivating variant GPCRs with important roles in the HPG axis, and describe what is known regarding the mechanisms by which PCs restore trafficking and function. We also discuss some of the merits and obstacles associated with taking this approach forward into a clinical setting.

The diagnosis and prevalence of hypoprolactinemia in patients with panhypopituitarism and the effects on depression and sexual functions

PURPOSE

We aimed to investigate the prevalence and the diagnostic criteria of hypoprolactinemia in patients with panhypopituitarism and the effects of hypoprolactinemia on depression and sexual functions.

MATERIALS AND METHODS

Forty-eight patients with panhypopituitarism and 20 healthy volunteers were included. Basal hormone levels were measured and a TRH stimulation test was performed. For the evaluation of sexual functions, questionnaries of Female Sexual Functional Index (FSFI) for females and International Erectile Functional Index for males were performed to the subjects. Depressive symptoms were evaluated by Beck Depression Envontory score (BDI-II).

RESULTS

The peak PRL response to TRH stimulation test at 5th percentile in the control group was 18.6 ng/ml in males and 41.6 ng/ml in females and accepted as the cut-offs for sufficient response of PRL. Prolactin was insufficient in 42(87.5%) patients. A basal PRL level of ≤ 5.7 ng/ml in males and 7.11 ng/ml in females was 100% specific in predicting an inadequate response to TRH stimulation test with 80% and 70% sensitivity respectively. A basal PRL level of ≥ 8.5 ng/dl in males was 100% specific and 76% sensitive, and in females a level of ≥ 15.2 ng/dl was 96% specific and 66% sensitive in predicting an adequate response to TRH. PRL deficient patients with panhypopituitarism had higher depression scores compared to the controls, lower sexual function scores in males.

CONCLUSION

PRL deficiency is prevalent among individuals with panhypopituitarism, with the potential to result in elevated depression scores in both sexes and impaired sexual functions in males. A basal PRL level seems to be sufficient for the diagnosis of hypoprolactinemia in routine clinical practice.

Neuroendocrine mechanisms in the links between early life stress, affect, and youth substance use: A conceptual model for the study of sex and gender differences

Early life stress (ELS) is defined as an acute or chronic stressor that negatively impacts a child's development. ELS is associated with substance use and mental health problems. This narrative literature review focuses on sex and gender differences in the effects of ELS on 1) adolescent neuroendocrine development; 2) pubertal brain maturation; and 3) development of internalizing symptoms and subsequent substance use. We posit that ELS may generate larger hormonal dysregulation in females than males during puberty, increasing internalizing symptoms and substance use. Future research should consider sex and gender differences in neuroendocrine developmental processes when studying the link between ELS and negative health outcomes.

Opioid-induced hypogonadism in opioid use disorder, its role in negative reinforcement, and implications for treatment and retention

Hypogonadism is a highly prevalent complication of chronic opioid use associated with a constellation of affective, algesic, and cognitive symptoms as well as decreased quality of life. Given that the mainstays of pharmacologic opioid use disorder (OUD) treatment - methadone and buprenorphine - are themselves agonists or partial agonists at the mu opioid receptor, opioid-induced hypogonadism (OIH) remains an underappreciated clinical concern throughout the course of OUD treatment. Prominent theoretical frameworks for OUD emphasize the importance of negative reinforcement and hyperkatifeia, defined as the heightened salience of negative emotional and motivational states brought on by chronic opioid use. In this perspective article, we highlight the striking parallels between the symptom domains of hyperfakifeia and hypogonadism in males, who comprise the vast majority of existing clinical research on OIH. By extension we propose that future research and ultimately clinical care should focus on the identification and treatment of OIH in OUD patients to help address the longstanding paradox of poor treatment retention despite efficacious therapies, particularly in the setting of the current opioid overdose epidemic driven by high potency synthetic opioids such as fentanyl. We then review evidence from chronic pain patients that testosterone replacement provides clinically significant benefits to men with OIH. Finally, using this framework, we compare extant OUD therapeutics and discuss critical gaps in the clinical literature-including the relative dearth of data regarding hypothalamic-pituitary-gonadal function in females who use opioids-where future study should be focused.

Guidelines for Rational Clinical Use of Fentanyl Transdermal Patch

Pain is one of the most common clinical symptoms of cancer patients, seriously affecting the quality of life of patients and bringing heavy mental and economic burden to families and society. The treatment of cancer pain in China is facing numerous challenges, one of which includes the irrational usage of analgesic drugs in clinical practice. As a strong opioid analgesic, transdermal fentanyl patch has been widely used due to its convenient clinical application and obvious therapeutic effect. Several basic-level hospitals and even general hospitals in China fail to appropriate the application of drugs in clinical application due to the lack of understanding of the pharmacological characteristics and clinical application of fentanyl transdermal patch by medical staff, seriously affecting the treatment quality. Therefore, it is imperative to strengthen the rational use and management of fentanyl transdermal patches. Accordingly, the initiation by the Cancer Rehabilitation and Palliative Treatment Professional Committee of the Hubei Anti-cancer Association launched the compilation of the "Guidelines for Rational Clinical Use of Fentanyl Transdermal Patch" (from now on referred to as the "Guidelines") in Hubei Province, China. The experts in the preparation group are experts in many disciplines, such as medicine, pharmacy, and nursing. The expert group determines the outline, prepares the required regulations, and revises it repeatedly. Moreover, these experts put forward suggestions for revision to strictly control the accuracy and scientific authenticity of the contents of the "Guide". Finally, all experts of the preparation team certify and finalize the draft. This "Guide" prepared by experts of the Cancer Rehabilitation and Palliative Treatment Professional Committee of the Hubei Anti-cancer Association and the expert advisory group with joint efforts, aims to play a positive role in promoting the rational clinical use of fentanyl transdermal patch, reducing the mental and economic burden of patients, and ensuring medical quality and medical safety.

Herba Epimedii and Increased Opioid Cravings While on Buprenorphine: A Case Report

Herba Epimedii, commonly known as yin yang huo, inyokaku, and horny goat weed, is a traditional Chinese herbal medicine utilized for treating osteoporosis and enhancing libido. Studies conducted in vitro have demonstrated that Herba Epimedii interacts with the enzyme cytochrome P450 3A4 (CYP3A4). This interaction poses a potential risk for drug-drug interactions, particularly with medications metabolized by CYP3A4, such as buprenorphine. This paper presents a case of a patient experiencing exacerbated opioid cravings following the initiation of Herba Epimedii. This is the first reported case supporting this interaction, emphasizing the necessity of screening for alternative medicines in patients undergoing medication-assisted treatments for opioid use disorder.

Influence of general anaesthesia on circulating biomarkers of glucose metabolism in pigs

Pigs are widely used in metabolic research with procedures often requiring general anaesthesia. The aim was to investigate the effect of four different anaesthetic protocols: 1) isoflurane inhalation, 2) propofol infusion, 3) a mixture of tiletamine, zolazepam, medetomidine, ketamine and butorphanol (TZMKB)) and 4) ketamine combined with midazolam and xylazine (KMX)) on selected biomarkers during basal and glucose stimulated conditions. Eight domestic pigs were included in a cross-over design. Plasma concentrations of glucose, insulin, C-peptide, glucagon, cortisol, triglycerides, total cholesterol, aspartate amino transferase and alanine amino transferase, creatinine, urea, fructosamine, albumin, free fatty acids (FFAs) and glycerol were measured at baseline, during 2 h of anaesthesia and during 1 h of recovery. Intravenous glucose tolerance test (IVGTT, 0.5 g glucose/kg) was performed after 1 h of anaesthesia. Glucose disappearance rate and areas under the insulin, C-peptide and glucagon curves from the IVGTT were calculated. All four anaesthetic protocols affected glucose metabolism parameters significantly compared with un-anaesthetised pigs, which was particularly evident during IVGTT and for TZMKB and KMX anaesthesia. Propofol additionally influenced the plasma concentrations of triglycerides, FFAs and glycerol significantly. The remaining circulating biomarkers were largely unaffected by anaesthesia. These data underline the importance of considering the anaesthetic protocol in porcine studies of circulating metabolic biomarkers.

Association Between Incident Type 2 Diabetes and Opium Use: Mediation by Body Mass and Adiposity

Opiates can affect glucose metabolism and obesity, but no large prospective study (to our knowledge) has investigated the association between long-term opium use, body mass index (BMI; weight (kg)/height (m)2), and incident type 2 diabetes mellitus (T2DM). We analyzed prospective data from 50,045 Golestan Cohort Study participants in Iran (enrollment: 2004-2008). After excluding participants with preexisting diseases, including diabetes, we used adjusted Poisson regression models to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for T2DM in opium users compared with nonusers, using mediation analysis to assess the BMI-mediated association of opium use with incident T2DM. Of 40,083 included participants (mean age = 51.4 (standard deviation, 8.8) years; 56% female), 16% were opium users (median duration of use, 10 (interquartile range), 4-20) years). During follow-up (until January 2020), 5,342 incident T2DM cases were recorded, including 8.5% of opium users and 14.2% of nonusers. Opium use was associated with an overall decrease in incident T2DM (IRR = 0.83, 95% CI: 0.75, 0.92), with a significant dose-response association. Most (84.3%) of this association was mediated by low BMI or waist circumference, and opium use did not have a direct association with incident T2DM (IRR = 0.97, 95% CI: 0.87, 1.08). Long-term opium use was associated with lower incidence of T2DM, which was mediated by low body mass and adiposity.

Clinical efficacy and patients' perception of virtual reality during wound care in adults: A systematic review with meta-analysis of randomised clinical trials

This study was aimed to review Virtual Reality's (VR) impact on pain, anxiety, opioid usage, physiological and behavioural responses, and patients' experience during wound care (WC) in adults. We searched multiple databases (Embase, Medline ALL, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, CINAHL, Scopus and Google Scholar) from inception until January 27th, 2023. Included studies compared VR alone or as an adjunct to standard WC with standard WC or other distraction methods, in adults with burn or non-burn-related wounds. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomised parallel-group and crossover trials. The review followed PRISMA guidelines for reporting. Fourteen studies were eligible for inclusion. The meta-analysis was limited to studies comprising solely of adult participants. VR reduced pain intensity compared to standard WC in all study designs. Despite not being included in the meta-analysis due to reasons such as mixed population or lack of sufficient statistical data, other studies showed significant pain reduction using VR. Additionally, VR improved patients' experience of WC. No clear effect was found on other outcomes including anxiety, opioid usage and physiological and behavioural responses. VR shows promise in reducing acute pain and enhancing patients' experience of WC. The observed variations in the effects of VR at group and individual levels indicate the need for a personalised treatment plan by selecting the right VR for the right patient given at the right time.

Mechanisms and predictors of menses resumption once normal weight is reached in anorexia nervosa

BACKGROUND

In cases of Anorexia Nervosa (AN), achieving weight gain recovery beyond the lower limits set by the World Health Organization and normalizing classical nutritional markers appears to be essential for most patients. However, this is not always adequate to restore menstrual cycles. This discrepancy can cause concern for both patients and healthcare providers, and can impact the medical management of these individuals. Thus, the purpose of this study was to assess the ability of anthropometric and hormonal factors to predict the resumption of menstrual cycles in individuals with anorexia nervosa upon reaching a normal body weight.

METHOD

Patients with AN who had achieved a normal Body Mass Index but had not yet resumed their menstrual cycles (referred to as ANRec) were evaluated on two occasions: first at visit 1 and then again 6 months later, provided their body weight remained stable over this period (visit 2). Among the 46 ANRec patients who reached visit 2, they were categorized into two groups: 20 with persistent amenorrhea (PA-ANRec) and 26 who had regained their menstrual cycles (RM-ANRec). Anthropometric measurements, several hormone levels, Luteinizing Hormone (LH) pulsatility over a 4-h period, and LH response to gonadotropin-releasing hormone injection (LH/GnRH) were then compared between the two groups at visit 1.

RESULTS

Patients in the RM-ANRec group exhibited higher levels of follicular stimulating hormone, estradiol, inhibin B, LH/GnRH, and lower levels of ghrelin compared to those in the PA-ANRec group. Analysis of Receiver Operating Characteristic curves indicated that having ≥ 2 LH pulses over a 4-h period, LH/GnRH levels ≥ 33 IU/l, and inhibin B levels > 63 pg/ml predicted the resumption of menstrual cycles with a high degree of specificity (87%, 100%, and 100%, respectively) and sensitivity (82%, 80%, and 79%, respectively).

CONCLUSIONS

These three hormonal tests, of which two are straightforward to perform, demonstrated a high predictive accuracy for the resumption of menstrual cycles. They could offer valuable support for the management of individuals with AN upon achieving normalized weight. Negative results from these tests could assist clinicians and patients in maintaining their efforts to attain individualized metabolic targets.

TRIAL REGISTRATION

IORG0004981.

The effect of intranasal oxytocin on social reward processing in humans: a systematic review

Understanding the neurobiology of social reward processing is fundamental, holding promises for reducing maladaptive/dysfunctional social behaviors and boosting the benefits associated with a healthy social life. Current research shows that processing of social (vs. non-social) rewards may be driven by oxytocinergic signaling. However, studies in humans often led to mixed results. This review aimed to systematically summarize available experimental results that assessed the modulation of social reward processing by intranasal oxytocin (IN-OXY) administration in humans. The literature search yielded 385 results, of which 19 studies were included in the qualitative synthesis. The effects of IN-OXY on subjective, behavioral, and (neuro)physiological output variables are discussed in relation to moderating variables-reward phase, reward type, onset and dosage, participants' sex/gender, and clinical condition. Results indicate that IN-OXY is mostly effective during the consumption ("liking") of social rewards. These effects are likely exerted by modulating the activity of the prefrontal cortex, insula, precuneus, anterior cingulate cortex, amygdala, and striatum. Finally, we provide suggestions for designing future oxytocin studies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021278945, identifier CRD42021278945.

Long-term opioid treatment and endocrine measures in chronic non-cancer pain patients

BACKGROUND

The prevalence of chronic non-cancer pain (CNCP) has increased dramatically the past decades, which combined with indiscriminate use of prescribed opioids has become a public health problem. Endocrine dysfunction may be a complication of long-term opioid treatment (L-TOT), but the evidence is limited. This study aimed at investigating the associations between L-TOT and endocrine measures in CNCP patients.

METHODS

Cortisol (spot and after stimulation), thyrotropin (TSH), thyroxin (T4), insulin-like growth factor 1 (IGF-1), prolactin (PRL), 17-hydroxyprogesterone, androstenedione, dehydroepiandrosterone (DHEAS), sex hormone-binding globulin (SHBG), total testosterone (TT) and free testosterone (fT) were measured. Group comparisons were done between CNCP patients in L-TOT and controls as well as between patients on high- or low-dose morphine equivalents.

RESULTS

Eighty-two CNCP patients (38 in L-TOT and 44 controls not receiving opioids) were included. Low TT (p = 0.004) and fT concentrations (p < 0.001), high SHBG (p = 0.042), low DEAS (p = 0.017) and low IGF-1 (p = 0.003) in men were found when comparing those in L-TOT to controls and high PRL (p = 0.018), low IGF-1 standard deviation score (SDS) (p = 0.006) along with a lesser, but normal cortisol response to stimulation (p = 0.016; p = 0.012) were found when comparing L-TOT to controls. Finally, a correlation between low IGF-1 levels and high opioid dose was observed (p < 0.001).

CONCLUSIONS

Our study not only supports previous findings but even more interestingly disclosed new associations. We recommend future studies to investigate endocrine effects of opioids in larger, longitudinal studies. In the meanwhile, we recommend monitoring endocrine function in CNCP patients when prescribing L-TOT.

SIGNIFICANCE

This clinical study found associations between L-TOT, androgens, growth hormone and prolactin in patients with CNCP compared to controls. The results support previous studies as well as add new knowledge to the field, including an association between high opioid dose and low growth hormone levels. Compared to existing research this study has strict inclusion/exclusion criteria, a fixed time period for blood sample collection, and adjustments for potential confounders, which has not been done before.

Reproductive and developmental toxicity assessments of LPM3480392, a novel mu opioid receptor biased agonist in rats

Opioids remain the most powerful analgesics for moderate to severe pain but their clinical use, misuse and abuse has been an alarming medical problem, especially for those users at child-bearing age. Mu-opioid receptor (MOR) biased agonists have been suggested as superior alternatives with better therapeutic ratios. We recently discovered and characterized a novel MOR biased agonist, LPM3480392, which demonstrates robust analgesic effect, favorable pharmacokinetic performance, and mild respiratory suppression in vivo. To understand the safety profile of LPM3480392 on the reproductive system and embryonic development, this study evaluated the effects of LPM3480392 on the fertility and early embryonic development, embryo-fetal development, and pre- and postnatal development in rats. Results showed that LPM3480392 had mild effects on parental male and female animals, accompanied by subtle early embryonic loss and delayed ossification of fetal development during organogenesis period. In addition, although minor effects were found on normal developmental milestones and behaviors in the pups, there was no evidence of malformed effect. In conclusion, these results suggest that LPM3480392 has a favorable safety profile with only minor effects on the reproductive and developmental outcomes in animals, which support the development of LPM3480392 as a novel analgesic.

Mechanism associated with changes in male reproductive functions during ageing process

Ageing is a natural process with physiological changes in different body parts and has been associated with decreased reproductive capacity. Factors such as imbalance in the antioxidant defence system, vascular diseases, diabetes mellitus, accessory reproductive glands infection, obesity as well as buildup of toxic substances play a role in age-related male reproductive malfunction. Age is inversely proportional to volume of semen, sperm count, sperm progressive motility, sperm viability, normal sperm morphology. The observed negative correlation between ageing and semen indices contributes to male infertility and reproductive decline. Normal levels of ROS, plays crucial role in facilitating sperm function, such as capacitation, hyper-activation, acrosome reaction as well as sperm-oocyte fusion; however, a substantial elevation in the endogenous level of ROS, especially in reproductive tissues, usually instigates destruction of sperm cells and heightened male infertility. Contrarily, antioxidants, such as vitamins C and E, beta-carotene, and micronutrients like zinc and folate, have been found by researchers to facilitate normal semen quality and male reproductive function. Furthermore, the role of hormonal imbalance as a result of the compromised hypothalamic-pituitary-gonadal axis, Sertoli and Leydig cells disorder, and nitric oxide-medicated erectile dysfunction during ageing cannot be undermined.

New perspectives in functional hypogonadotropic hypogonadism: beyond late onset hypogonadism

Functional hypogonadotropic hypogonadism (FHH) is an increasingly frequent condition, whose pathological mechanisms are not yet fully clarified. The concept of FHH has now completely replaced that of late onset hypogonadism, that only concerned the ageing man. FHH is the result of an impairment of the hypothalamic-pituitary gonadal axis (HPG-A) function, resulting in decreased testosterone concentrations associated with low or inappropriately normal gonadotropin levels and infertility; it can be diagnosed once organic causes of hypogonadism are excluded. The growing occurrence of FHH derives from its association with widespread conditions, such as obesity and diabetes mellitus, but also to the increasing ease and frequency of use of several drugs, such as opioids, glucocorticoids, and sex steroids. Moreover, given the tendency of many subjects to excessive physical activity and drastic reduction in caloric intake, FHH may also be secondary to low energy availability. Finally, the association with HIV infection should not be overlooked. Therefore, there is an important variability in the diseases that can lead to FHH. Despite the heterogeneity of the underlying pathologies, the mechanisms leading to FHH would seem quite similar, with the initial event represented by the impairment at the HPG-A level. Nevertheless, many different biological pathways are involved in the pathogenesis of FHH, therefore the aim of the current paper is to provide an overview of the main relevant mechanisms, through a detailed analysis of the literature, focusing specifically on pathogenesis and clinical, diagnostic and therapeutic aspects.

Clinical application of electroacupuncture in enhanced recovery after surgery

Enhanced recovery after surgery (ERAS) is currently the recommended surgical strategy, the main content of which is to reduce perioperative stress response and postoperative complications through perioperative multimodal analgesia and intensive surgery. Since ERAS was introduced, many rehabilitation medicine teams have been deeply involved, including physical therapy, occupational therapy, nutrition therapy and psychological counseling. However, ERAS lacks several powerful means to address perioperative prognostic issues. Therefore, how to further improve the effects of ERAS, reduce perioperative complications and protect vital organ functions has become an urgent problem. With the continuous development of traditional Chinese medicine, electroacupuncture (EA) has been widely used in various clinical applications, and its efficacy and safety have been fully proved. Recent studies have shown that the application of EA in ERAS has had an important impact on rehabilitation researches. In terms of reducing complications, the therapeutic effects of EA treatment mainly include: reducing pain and the use of analgesics; Improvement of postoperative nausea and vomiting; Postoperative immune function treatment; Relieve anxiety and depression. In addition, EA also protects the recovery of physiological functions, including cardiovascular function, cerebrovascular function and gastrointestinal function, etc. To sum up, the complementary strengths of EA and ERAS will allow them to develop and combine. This review discusses the potential value and feasibility of EA in ERAS from the aspects of improving perioperative efficacy and protecting organ functions.

Engineering human spinal microphysiological systems to model opioid-induced tolerance

pioids are commonly used for treating chronic pain. However, with continued use, they may induce tolerance and/or hyperalgesia, which limits therapeutic efficacy. The human mechanisms of opioid-induced tolerance and hyperalgesia are significantly understudied, in part, because current models cannot fully recapitulate human pathology. Here, we engineered novel human spinal microphysiological systems (MPSs) integrated with plug-and-play neural activity sensing for modeling human nociception and opioid-induced tolerance. Each spinal MPS consists of a flattened human spinal cord organoid derived from human stem cells and a 3D printed organoid holder device for plug-and-play neural activity measurement. We found that the flattened organoid design of MPSs not only reduces hypoxia and necrosis in the organoids, but also promotes their neuron maturation, neural activity, and functional development. We further demonstrated that prolonged opioid exposure resulted in neurochemical correlates of opioid tolerance and hyperalgesia, as measured by altered neural activity, and downregulation of μ-opioid receptor expression of human spinal MPSs. The MPSs are scalable, cost-effective, easy-to-use, and compatible with commonly-used well-plates, thus allowing plug-and-play measurements of neural activity. We believe the MPSs hold a promising translational potential for studying human pain etiology, screening new treatments, and validating novel therapeutics for human pain medicine.

High-dose opioids for chronic non-cancer pain: an overview of Cochrane Reviews

BACKGROUND

This overview was originally published in 2017, and is being updated in 2022.  Chronic pain is typically described as pain on most days for at least three months. Chronic non-cancer pain (CNCP) is any chronic pain that is not due to a malignancy. Chronic non-cancer pain in adults is a common and complex clinical issue, for which opioids are prescribed by some physicians for pain management. There are concerns that the use of high doses of opioids for CNCP lacks evidence of effectiveness, and may increase the risk of adverse events.

OBJECTIVES

To describe the evidence from Cochrane Reviews and overviews regarding the efficacy and safety of high-dose opioids (defined as 200 mg morphine equivalent or more per day) for CNCP.

METHODS

We identified Cochrane Reviews and overviews by searching the Cochrane Database of Systematic Reviews in The Cochrane Library. The date of the last search was 21 July 2022. Two overview authors independently assessed the search results. We planned to analyse data on any opioid agent used at a high dose for two weeks or more for the treatment of CNCP in adults.

MAIN RESULTS

We did not identify any reviews or overviews that met the inclusion criteria. The excluded reviews largely reflected low doses or titrated doses, where all doses were analysed as a single group; we were unable to extract any data for high-dose use only.

AUTHORS' CONCLUSIONS

There is a critical lack of high-quality evidence, in the form of Cochrane Reviews, about how well high-dose opioids work for the management of CNCP in adults, and regarding the presence and severity of adverse events.  No evidence-based argument can be made on the use of high-dose opioids, i.e. 200 mg morphine equivalent or more daily, in clinical practice. Considering that high-dose opioids have been, and are still being used in clinical practice to treat CNCP, knowing about the efficacy and safety of these higher doses is imperative.

The Role of Physical Exercise in Opioid Substitution Therapy: Mechanisms of Sequential Effects

It is generally accepted that chronic opioid use is associated with structural and functional changes in the human brain that lead to an enhancement of impulsive behavior for immediate satisfaction. Interestingly, in recent years, physical exercise interventions have been used as an adjunctive treatment for patients with opioid use disorders (OUDs). Indeed, exercise has positive effects on both the biological and psychosocial basis of addiction, modifying neural circuits such as the reward, inhibition, and stress systems, and thus causing behavioral changes. This review focuses on the possible mechanisms that contribute to the beneficial effects of exercise on the treatment of OUDs, with emphasis placed on the description of a sequential consolidation of these mechanisms. Exercise is thought to act initially as a factor of internal activation and self-regulation and eventually as a factor of commitment. This approach suggests a sequential (temporal) consolidation of the functions of exercise in favor of gradual disengagement from addiction. Particularly, the sequence in which the exercise-induced mechanisms are consolidated follows the pattern of internal activation-self-regulation-commitment, eventually resulting in stimulation of the endocannabinoid and endogenous opioid systems. Additionally, this is accompanied by modification of molecular and behavioral aspects of opioid addiction. Overall, the neurobiological actions of exercise in combination with certain psychological mechanisms appear to promote its beneficial effects. Given the positive effects of exercise on both physical and mental health, exercise prescription is recommended as a complement to conventional therapy for patients on opioid maintenance treatment.

Endometriosis and Opioid Receptors: Are Opioids a Possible/Promising Treatment for Endometriosis?

Endometriosis (EM), defined as the presence of endometrial-like tissue with surrounding smooth muscle cells outside the uterus, is a disregarded gynecological disease reported to affect 6-10% of women of reproductive age, with 30-50% of them suffering from chronic pelvic pain and infertility. Since the exact pathogenic mechanisms of EM are still unclear, no curative therapy is available. As pain is an important factor in EM, optimal analgesia should be sought, which to date has been treated primarily with non-steroidal anti-inflammatory drugs (NSAIDs), metamizole or, in extreme cases, opioids. Here, we review the pain therapy options, the mechanisms of pain development in EM, the endogenous opioid system and pain, as well as the opioid receptors and EM-associated pain. We also explore the drug abuse and addiction to opioids and the possible use of NOP receptors in terms of analgesia and improved tolerability as a target for EM-associated pain treatment. Emerging evidence has shown a promising functional profile of bifunctional NOP/MOP partial agonists as safe and nonaddictive analgesics. However, until now, the role of NOP receptors in EM has not been investigated. This review offers a thought which still needs further investigation but may provide potential options for relieving EM-associated pain.

Endocrine-related adverse conditions in patients receiving immune checkpoint inhibition: an ESE clinical practice guideline

Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment but are associated with significant autoimmune endocrinopathies that pose both diagnostic and treatment challenges. The aim of this guideline is to provide clinicians with the best possible evidence-based recommendations for treatment and follow-up of patients with ICI-induced endocrine side-effects based on the Grading of Recommendations Assessment, Development, and Evaluation system. As these drugs have been used for a relatively short time, large systematic investigations are scarce. A systematic approach to diagnosis, treatment, and follow-up is needed, including baseline tests of endocrine function before each treatment cycle. We conclude that there is no clear evidence for the benefit of high-dose glucocorticoids to treat endocrine toxicities with the possible exceptions of severe thyroid eye disease and hypophysitis affecting the visual apparatus. With the exception of thyroiditis, most endocrine dysfunctions appear to be permanent regardless of ICI discontinuation. Thus, the development of endocrinopathies does not dictate a need to stop ICI treatment.

Immunomodulatory effects of fentanyl and morphine on DSS- and TNBS-induced colitis

BACKGROUND

Opioid prescription for inflammatory bowel disease (IBD)-related pain is on the rise. However, the use of strong opioids can result in severe complications, and even death, in IBD patients. This study aimed to define the role of fentanyl and morphine, two representative strong opioids, in the pathogenesis of dextran sodium sulfate (DSS)- and 2,4,6-trinitrobenzenesulfonic acid solution (TNBS)-induced colitis.

METHOD

DSS and TNBS models were induced in C57BL/6J and Balb/c mice, respectively. Disease activity index (DAI), histopathology, enzyme-linked immunosorbent assay (ELISA), multiplex ELISA, and flow cytometry were performed to evaluate the effects of fentanyl and morphine.

RESULT

Fentanyl exacerbated DSS- and TNBS-induced colitis, while morphine exhibited no significant immunomodulatory effect. Fentanyl and morphine had no obvious effects on the serum levels of adrenocorticotropic hormone (ACTH), glucocorticoid (GC), and prostaglandin E2 (PGE-2) in DSS and TNBS models. Fentanyl elevated the proportions of Th1 cells, μ-opioid receptor (MOR) + Th1 cells, and MOR + macrophages in the colonic mucosa of DSS-treated mice, and enhanced the proportions of Th1 cells, macrophages, MOR + Th1 cells, and MOR + macrophages in the colonic mucosa of TNBS-treated mice. We found that fentanyl upregulated the levels of inflammatory cytokines/chemokines in MOR + macrophages of the colonic lamina propria mononuclear cells (LPMCs) from DSS-treated mice, whereas it had no effect on the expression of most inflammatory cytokines/chemokines in MOR + macrophages in the colonic LPMCs from TNBS-treated mice.

CONCLUSION

Our findings suggest that fentanyl exacerbates murine colitis via Th1 cell- and macrophage-mediated mechanisms, while morphine exhibits no significant immunomodulatory effect.

Detection of vaping, cannabis use, and hazardous prescription opioid use among adolescents

There has been a global surge in adolescents' use of electronic nicotine delivery systems (vaping), cannabis (vaped and edible), and prescription opioids, collectively termed ECPO. The nature of ECPO use can make it difficult to detect due to few obvious immediate physical and behavioural signs, as well as subtle long-term effects that allow adolescents to transition from initial exploration into hazardous ECPO use without easy detection by care providers. Here, we address the nature of the presentation of ECPO use in adolescents (roughly age 13-18 years), including challenges in detecting use and related complications, which affect screening, prevention, and intervention. We begin by reviewing empirical data on these difficult to detect effects in adolescents, including acute effects at cellular and neural levels and long-term neurocognitive and developmental changes that precede outwardly detectable physical signs. We then provide concrete approaches for providers to screen for ECPO use in adolescents even in the absence of overt physical and behavioural symptoms. Finally, we conclude with direct practice recommendations for prevention and intervention.

Analgesia during Parturition in Domestic Animals: Perspectives and Controversies on Its Use

This article analyzes the physiological role of pain during parturition in domestic animals, discusses the controversies surrounding the use of opioids, non-steroidal anti-inflammatory drugs (NSAIDs), and local analgesics as treatments during labor, and presents the advantages and disadvantages for mother and offspring. Labor is a potentially stressful and painful event, due to the contractions that promote expulsion of the fetus. During labor, neurotransmitters such as the prostaglandins contribute to the sensitization of oxytocin receptors in the myometrium and the activation of nociceptive fibers, thus supporting the physiological role of pain. Endogenously, the body secretes opioid peptides that modulate harmful stimuli and, at the same time, can inhibit oxytocin's action in the myometrium. Treating pain during the different stages of parturition is an option that can help prevent such consequences as tachycardia, changes in breathing patterns, and respiratory acidosis, all of which can harm the wellbeing of offspring. However, studies have found that some analgesics can promote myometrial contractility, increase expulsion time, affect fetal circulation, and alter mother-offspring recognition due to hypnotic effects. Other data, however, indicate that reducing the number of uterine contractions with analgesics increases their potency, thus improving maternal performance. Managing pain during labor requires understanding the tocolytic properties of analgesics and their advantages in preventing the consequences of pain.

Evidence of alterations of Beta-endorphin levels and Mu-opioid receptor gene expression in bipolar disorder

Despite the well-recognized effects of endogenous opioids on mood and behavior, research on its role in bipolar disorder (BD) is still limited to small or anecdotal reports. Considering that Beta-endorphins (β-END) and Mu-opioid receptors (MOR), in particular, have a crucial activity in affective modulation, we hypothesized their alteration in BD. A cross-sectional study was conducted. We compared: (1) BD type I (BD-I) patients (n = 50) vs healthy controls (n = 27), (2) two BD-I subject subgroups: manic (MAN; n = 25) vs depressed (DEP; n = 25) subjects. Plasma levels of β-END and MOR gene expression in peripheral blood mononuclear cells were analyzed using ELISA Immunoassay qRT-PCR. We found that subjects with BD exhibited a significant upregulation of MOR gene expression and a decrease of β-END (p<0.0001 for both). MAN display higher MOR levels than DEP (p<0.001) and HC (p<0.0001). Plasma levels of β-END were lower in DEP compared to MAN (p<0.05) and HC (p<0.0001). The main limitations are the cross-sectional design and the lack of a group of euthymic subjects. Although preliminary, our results suggest a dysregulation of the endogenous opioid systems in BD. In particular, both MAN and DEP showed a reduction of β-END levels, whereas MAN was associated with MOR gene overexpression.

Impact of maternal substance use on offspring's cardiovascular health

Substance use (SU) during pregnancy is on the rise, posing significant risks to the developing fetus. The adverse impact of maternal alcohol and nicotine use during the perinatal period on offspring health has been well established, including their associations with adverse cardiovascular health in offspring. However, limited studies examine the impact of other well-known SU utilized during pregnancy on offspring's cardiovascular health. This review summarizes the proposed mechanism of action of four commonly utilized substances: cocaine, marijuana, methamphetamine, and opioids, and their cardiovascular impact. Furthermore, we will review the current understanding of the adverse impact of substance use during pregnancy on offspring's cardiovascular system based on existing studies. This review will also highlight possible molecular mechanisms underlying the in-utero adverse programming of offspring's cardiovascular system secondary to SU in pregnancy and address the gaps in current understanding of how SU adversely impacts the developing cardiovascular system of offspring in utero.

Management of opioid use disorder and associated conditions among hospitalized adults: A Consensus Statement from the Society of Hospital Medicine

Hospital-based clinicians frequently care for patients with opioid withdrawal or opioid use disorder (OUD) and are well-positioned to identify and initiate treatment for these patients. With rising numbers of hospitalizations related to opioid use and opioid-related overdose, the Society of Hospital Medicine convened a working group to develop a Consensus Statement on the management of OUD and associated conditions among hospitalized adults. The guidance statement is intended for clinicians practicing medicine in the inpatient setting (e.g., hospitalists, primary care physicians, family physicians, advanced practice nurses, and physician assistants) and is intended to apply to hospitalized adults at risk for, or diagnosed with, OUD. To develop the Consensus Statement, the working group conducted a systematic review of relevant guidelines and composed a draft statement based on extracted recommendations. Next, the working group obtained feedback on the draft statement from external experts in addiction medicine, SHM members, professional societies, harm reduction organizations and advocacy groups, and peer reviewers. The iterative development process resulted in a final Consensus Statement consisting of 18 recommendations covering the following topics: (1) identification and treatment of OUD and opioid withdrawal, (2) perioperative and acute pain management in patients with OUD, and (3) methods to optimize care transitions at hospital discharge for patients with OUD. Most recommendations in the Consensus Statement were derived from guidelines based on observational studies and expert consensus. Due to the lack of rigorous evidence supporting key aspects of OUD-related care, the working group identified important issues necessitating future research and exploration.

Long-term opioid treatment and endocrine measures in patients with cancer-related pain: a systematic review

OBJECTIVES

Opioid analgesics are the main stay for cancer pain management; however, long-term opioid treatment (L-TOT) may suppress the endocrine system. This systemic review aimed at investigating effects of L-TOT on the endocrine system in patients with cancer-related pain.

METHODS

A search on MEDLINE, EMBASE and Web of Science databases was performed. Inclusion criteria were clinical studies investigating endocrine measures in adult patients with cancer-related pain in L-TOT (≥4 weeks). Outcomes and quality of evidence were assessed.

RESULTS

A total of 252 abstracts were identified; out of which 247 were excluded and five cross-sectional studies were included and analyzed. L-TOT was associated with lower serum concentration levels of total- and free testosterone in males, follicular stimulating hormone in females, and luteinizing hormone in both sexes. Moreover, higher morphine equivalent daily doses (MEDDs) were correlated with higher levels of cortisol and lower levels of LH in both sexes, and lower levels of total- and free testosterone in males. Sexual dysfunction was associated with low sex hormone levels. Level of evidence was low/very low.

CONCLUSIONS

The studies identified demonstrated that patients with cancer-related pain in L-TOT may have gonadal hypofunction causing sexual dysfunction, which may be correlated with opioid dose level. In addition, high serum concentrations of cortisol were positively correlated with high opioid dose levels. However, the evidence was weak and further research is necessary. PROSPERO, ID-number: CRD42020213059.

[Adverse effects of opioids, antidepressants and anticonvulsants on sex hormones : Often unnoticed but clinically relevant]

Androgen insufficiency under treatment with opioids, antidepressants and anticonvulsants in chronic pain diseases is a side effect with a high prevalence. It can lead to clinical metabolic alterations, adynamia, stress intolerance, anemia or osteoporosis and has a significant impact on the quality of life. Opioids, antidepressants and anticonvulsants affect the hypothalamic-pituitary-gonadal axis of sex hormones. A urologist, andrologist or endocrinologist should be involved in the treatment at an early stage. The recommendation of a differential therapeutic selection of certain substances is only indicative and does not meet evidential criteria. The indications for androgen substitution must be individualized and in consideration of the risk-benefit profile. Awareness of this side effect of an otherwise lege artis medicinal pain therapy must be sharpened and compulsory included in the differential diagnostic considerations.

The Kappa Opioid Receptor: A Promising Therapeutic Target for Multiple Pathologies

Kappa-opioid receptors (KOR) are widely expressed throughout the central nervous system, where they modulate a range of physiological processes depending on their location, including stress, mood, reward, pain, inflammation, and remyelination. However, clinical use of KOR agonists is limited by adverse effects such as dysphoria, aversion, and sedation. Within the drug-development field KOR agonists have been extensively investigated for the treatment of many centrally mediated nociceptive disorders including pruritis and pain. KOR agonists are potential alternatives to mu-opioid receptor (MOR) agonists for the treatment of pain due to their anti-nociceptive effects, lack of abuse potential, and reduced respiratory depressive effects, however, dysphoric side-effects have limited their widespread clinical use. Other diseases for which KOR agonists hold promising therapeutic potential include pruritis, multiple sclerosis, Alzheimer’s disease, inflammatory diseases, gastrointestinal diseases, cancer, and ischemia. This review highlights recent drug-development efforts targeting KOR, including the development of G-protein–biased ligands, mixed opioid agonists, and peripherally restricted ligands to reduce side-effects. We also highlight the current KOR agonists that are in preclinical development or undergoing clinical trials.

Elastographic evaluation of the effect of sickle cell anemia on testicles: a prospective study

To quantitatively determine testicular tissue stiffness values using shear wave elastography (SWE) in males that have sickle cell anemia (SCA) and to evaluate the relationship between elastography results and semen analysis parameters and hormone levels. Fifty patients diagnosed with SCA and followed up in the hematology outpatient clinic were evaluated in the urology outpatient clinic as the study group. In addition, there were 88 patients without any SCA-related complaints in the control group. We compared these groups with respect to their values, spermiogram parameters, testicular volume, and SWE values. Among patients in the SCA group, 28% had impaired sperm parameters. When testicular elastography was assessed, the testicular volumes were materially lower in the SCA group in comparison to the control group [right testicular volume: 14.76 (12.77-18.12) and 19.68 (15.12-24.18), respectively, p < 0.001; left testicular volume: 14.11 (11.06-17.32) and 16.59 (13.38-20.13), respectively, p = 0.015]. Additionally, the left testis central stiffness and the left testis inferior stiffness were significantly higher in the SCA group (p < 0.001 and p = 0.014, respectively). The age and hydroxyurea use had a worse effect on sperm parameters in patients with SCA (odds ratio: -0.161 and -1.914, standard deviation: 0.071 and 0.921, and p = 0.024 and p = 0.038, respectively). We consider that the technique utilized in this study for SWE values is fast and can be adopted as a reliable diagnostic tool and follow-up practice in routine clinical practice to evaluate the acuteness of damage to the testicles in patients having SCA.

Genetic liability for prescription opioid use and risk of cardiovascular diseases: a multivariable Mendelian randomization study

BACKGROUND AND AIMS

Observational studies have yielded conflicting results on the association of prescription opioid use (POU) with the risk of cardiovascular diseases (CVD). Residual confounding and potential reverse causality are inevitable in such conventional observational studies. This study used Mendelian randomization (MR) design to estimate the causal effect of POU on the risk of CVD, including coronary heart disease (CHD), myocardial infarction (MI) and ischemic stroke (IS), as well as their common risk factors.

DESIGN

We estimated the causal effect of genetic liability for POU on CVD in a two-sample MR framework. Complementary sensitivity analyses were conducted to test the robustness of our results.

SETTING

Genome-wide association studies (GWAS) that were based on predominantly European ancestry.

PARTICIPANTS

The sample sizes of the GWAS used in this study ranged from 69 033 to 757 601 participants.

MEASUREMENTS

Genetic variants predictive of the POU and their corresponding summary-level information in the outcomes were retrieved and extracted from the respective GWAS.

FINDINGS

Using univariable MR, we found evidence for a causal effect of genetic liability for POU on an increased risk of CHD [odds ratio (OR) = 1.09; 95% confidence interval (CI) = 1.02-1.16; P = 0.008] and MI (OR = 1.13; 95% CI = 1.04-1.22; P = 0.002). In multivariable MR, the association remained after accounting for comorbid pain conditions, but was attenuated with adjustment for potential mediators, including body mass index (BMI), waist circumference (WC) and type 2 diabetes (T2D).

CONCLUSION

Mendelian randomization estimates provide robust evidence for the causal effects of genetic liability for prescription opioid use on an increased risk of coronary heart disease and myocardial infarction, which might be mediated by obesity-related traits.

Less Well-Known Consequences of the Long-Term Use of Opioid Analgesics: A Comprehensive Literature Review

BACKGROUND

The adverse effects of short-term opioid analgesics are well known and acknowledged; however, the spectrum of the sequelae of long-term use seems less clear. Some effects may remain undetected but still have the potential to cause harm and reduce patients' quality of life.

OBJECTIVE

To review the literature on the adverse effects of long-term opioid therapy.

METHODS

We performed a quasi-systematic search, analyzing articles published in the MEDLINE database between January 2000 and March 2021 that identified adverse effects of opioids used for chronic pain treatment.

RESULTS

Growing evidence indicates that there are multiple serious adverse effects of opioid treatment. Long-term opioid use may have significant effects on the endocrine, immune, cardiovascular, respiratory, gastrointestinal, and neural systems. Studies show that long-term opioid treatment increases the risk of fractures, infections, cardiovascular complications, sleep-disordered breathing, bowel dysfunction, overdose, and mortality. Opioids may potentially affect cancer development. Most consequences of the long-term use of opioids have been identified in studies of patients with non-malignant pain.

CONCLUSION

Studies indicate that long-term use of opioids increases the risk of drug-related events in a significant number of patients. Clinicians should be aware of these complications associated with prescribing opioids, discuss them with patients, prevent complications, if possible, and diagnose them early and manage adequately. More human studies are needed to assess the risk, including trials with individual opioids, because they have different adverse effect profiles.

Relevance of cortisol and copeptin blood concentration changes in an experimental pain model

The effect of pain and analgesics on stress biomarkers is not well studied. We evaluated the effect of acute pain and analgesics on serum cortisol and copeptin in an experimental pain model in healthy volunteers. Healthy volunteers presented at 8 a.m. for an experimental pain stimulation. Cortisol and copeptin levels were measured before, during and after electrophysiological stimulation, first before and then during opioid delivery. Difference in biomarker levels compared to baseline levels was calculated, and potential influencing factors were evaluated by linear regression analysis. Cortisol decreased by 13% during the 10 min of rest at baseline, but copeptin did not change significantly. Cortisol had a median decrease of −24% or −83 nmol/l (−44 to −124 nmol/l, p = 0.0002) during the electrophysiological stimulation training session, while the median difference for copeptin was −22% or −1.01 pmol/l (−2.35 to 0.08 pmol/l, p = 0.0003). After administration of opioids, cortisol did not decrease but increased by 3% (p = 0.043), indicating an increasing opioids effect on cortisol. This effect was not visible for copeptin (median change −0.003 pmol/l (−0.50 to 0.24), p = 0.45). In this experimental pain model performed in the morning, moderate pain did not have a relevant effect on cortisol or copeptin levels, whereas opioids led to a discrete peak of cortisol.

Clinicaltrials.gov identifier: NCT01975753 (registered on November 5, 2013, before start of recruitment).

The Effect of Different Opioids on Acid-Base Balance and Blood Gas Analysis in Hospitalized Dogs

Pain management is central to veterinary practice, contributing to successful case outcomes and enhancement of the veterinarian-client-patient relationship. Analgesic drugs represent one of the pillars of the multimodal approach to acute and chronic pain management. In dogs, the most used opioids are methadone, buprenorphine and tramadol. Several episodes of hypoglycemia in people treated with tramadol and methadone have recently been described. The aim of this work is to evaluate the changes in the glycemic and acid-base balance induced by tramadol, methadone and buprenorphine in hospitalized dogs. A retrospective review of the medical records of dogs hospitalized for both medical and surgical reasons was performed. During 2018-2020, a total of 876 canine patients were treated with opioids, including 228 with tramadol, 273 with methadone and 375 with buprenorphine. Of all these dogs, only a small percentage met the inclusion criteria presented in the initial design. All the hospitalized animals were monitored daily through clinical examination and blood sampling. Blood samples were obtained before opioid administration (T0), and 24 h (T1) and 48 h (T2) after °pioid administration. The following parameters were evaluated: blood gas value (pH, pCO₂), acid-base state (cHCO₃), oxymetric values (ctHb, haematocrit), electrolyte values (K+, Na+, iCa, Cl-) and metabolic values (glucose, lactate, anion GAP K+c). The glycemic value in enrolled dogs showed a decrease over time, regardless of the type of opioid used, but remained within the physiological range. The highest average glycemic drop was recorded for methadone, between T0 and T1, followed by tramadol between T1 and T2, while buprenorphine recorded the highest overall glycemic drop between T0-T2 when compared to the other two opioids. Female dogs showed the greatest drop in glycemic value. Lactate concentration always presented values beyond the physiological range at an early stage, which then normalized quickly. Measurement of electrolyte concentrations showed a consistent increase in the values of iCa, Na and Cl. In hospitalized dogs treated with opioids monitoring of gas analytic parameters is important and more attention should be paid to patients hospitalized with certain metabolic and endocrine diseases.

Changes of plasma concentration and gene expression of ghrelin and leptin in rats receiving kisspeptin and morphine

Kisspeptin is a hypothalamic peptide which stimulates hypothalamus- pituitary- gonadal (HPG) axis. Morphine is an alkaloid which suppresses reproduction. Ghrelin and leptin are metabolic peptides which play role in relaying information to the HPG axis. In the present study, the interaction effects of kisspeptin and morphine were investigated on plasma and gene expression levels of leptin and ghrelin. Twenty adult male Wistar rats randomized in four groups were received injection of saline, kisspeptin (1.00 nmol), morphine (5.00 mg kg^-1) or Kisspeptin + morphine. Rats were received kisspeptin and morphine via third cerebral ventricular and subcutaneous injection, respectively. Ten male rats in two groups were received intravenous injection of saline or kisspeptin (7.50 nmol). Blood samples, hypothalamic and adipose tissue samples were collected. Plasma and gene expression levels of ghrelin and leptin were measured using the methods of enzyme-linked immunosorbent assay and real time-PCR, respectively. Morphine significantly increased plasma concentration and hypothalamic mRNA levels of ghrelin compared to saline while kisspeptin significantly decreased them compared to saline. Morphine significantly decreased plasma and mRNA levels of leptin in adipose tissue compared to saline, however, kisspeptin did not increase plasma and mRNA levels of leptin in adipose tissue compared to saline. Kisspeptin significantly decreased the effects of morphine on plasma concentration and hypothalamic gene expression levels of ghrelin compared to morphine alone, however, it did not affect morphine influence on plasma and leptin gene expression levels compared to morphine alone. Kisspeptin and morphine might partly be involved in the regulation of reproductive activity via regulation the metabolic hormones synthesis.

Opioids and pituitary function: expert opinion

PURPOSE

Opioids are highly addictive potent analgesics and anti-allodynics whose use has dramatically increased in recent decades. The precipitous rise in opioid dependency and opioid use disorder is an important public health challenge given the risks for severely adverse health outcomes. The long-term opioid impact on hypothalamic-pituitary axes is particularly underappreciated among both endocrinologists and primary care physicians. We review the effects of opioids on hypothalamic-pituitary-target gland function and their implications for clinical practice.

METHODS

Experts in hypothalamic-pituitary disorders and opioid pharmacology reviewed recently published literature and considered strategies for diagnosing and managing these opioid-induced endocrine effects.

RESULTS

Opioid suppression of hypothalamic-pituitary axes can lead to hypogonadotropic hypogonadism, central adrenal insufficiency, and hyperprolactinemia. These important clinical manifestations are often under-estimated, poorly evaluated, and typically either untreated or not optimally managed. Data on biochemical testing for diagnosis and on the effect of hormone replacement in these patients is limited and prospective randomized controlled studies for guiding clinical practice are lacking.

CONCLUSIONS

Patients should be informed about risks for hypogonadism, adrenal insufficiency, and hyperprolactinemia, and encouraged to report associated symptoms. Based on currently available evidence, we recommend clinical and biochemical evaluation for potential central adrenal insufficiency, central hypogonadism, and/or hyperprolactinemia in patients chronically treated with opioids as well as the use of current expert guidelines for the diagnosis and treatment of these conditions.

Intergenerational effects of preconception opioids on glucose homeostasis and hepatic transcription in adult male rats

Adolescence represents a period of significant neurodevelopment during which adverse experiences can lead to prolonged effects on disease vulnerability, including effects that can impact future offspring. Adolescence is a common period for the initiation of drug use, including the use of opioids. Beyond effects on central reward, opioids also impact glucose metabolism, which can impact the risk of diabetes. Moreover, recent animal models suggest that the effects of adolescent opioids can effect glucose metabolism in future offspring. Indeed, we demonstrated that the adult male offspring of females exposed to morphine for 10 days during adolescence (referred to as MORF1 males) are predisposed to the adverse effects of an obesogenic diet. As adults, MORF1 males fed a high fat moderate sucrose diet (FSD) for just 6 weeks had increased fasting glucose and insulin levels when compared to age-matched offspring of females exposed to saline during adolescence (SALF1 males). Clinically, a similar profile of impaired fasting glucose has been associated with hepatic insulin resistance and an increased risk of non-alcoholic fatty liver disease. Thus, in the current study, we used RNA sequencing to determine whether adult MORF1 males demonstrate significant alterations in the hepatic transcriptome suggestive of alterations in metabolism. Age-matched SALF1 and MORF1 males were fed either FSD or control diet (CD) for 8 weeks. Similar to our previous observations, FSD-maintained MORF1 males gained more weight and displayed both fasting hyperglycemia and hyperinsulinemia when compared to FSD-maintained SALF1 males, with no significant effect on glucagon. No differences in bodyweight or fasting-induce glucose were observed in control diet (CD)-maintained F1 males, although there was a trend for CD MORF1 males to display elevated levels of fasting insulin. Unexpectedly, transcriptional analyses revealed profound differences in the hepatic transcriptome of CD-maintained MORF1 and SALF1 (1686 differentially expressed genes) with no significant differences between FSD-maintained MORF1 and SALF1 males. As changes in the hepatic transcriptome were not revealed under 8 weeks FSD conditions, we extended the feeding paradigm and conducted a glucose tolerance test to determine whether impaired fasting glucose observed in FSD MORF1 males was due to peripheral insulin resistance. Impaired glucose tolerance was observed in both CD and FSD MORF1 males, and to a more limited extent in FSD SALF1 males. These findings implicate intergenerational effects of adolescent morphine exposure on the risk of developing insulin resistance and associated comorbidities, even in the absence of an obesogenic diet.

Doping in Racing Pigeons (Columba livia domestica): A Review and Actual Situation in Belgium, a Leading Country in This Field

Pigeon racing is a sport in which trained homing pigeons (Columba livia domestica) are released between 60 and 1200 km from their loft and then have to return home as quickly as possible. The first race was held in 1818 in Belgium and since then, Belgium has led the world in pigeon breeding. Unfortunately, as in other sports, doping has become a major issue and doping controls have been implemented. This review provides information about pigeon racing, rules from the Royal Federation Colombophile of Belgium, and laws applicable in Belgium as doping control issues cannot be understood without including them as part of pigeon racing. The main pharmacological data concerning corticoids, non-steroidal anti-inflammatory drugs, anabolic steroids, pain relievers and narcotic analgesics, bronchodilators and β-agonists, drugs acting on the central nervous system and other performance-enhancing drugs, in addition to methods relevant to doping in pigeons are presented. Moreover, the chosen matrix and analytical methods are described.

The placenta as a target of opioid drugs†

Opioid drugs are analgesics increasingly being prescribed to control pain associated with a wide range of causes. Usage of pregnant women has dramatically increased in the past decades. Neonates born to these women are at risk for neonatal abstinence syndrome (also referred to as neonatal opioid withdrawal syndrome). Negative birth outcomes linked with maternal opioid use disorder include compromised fetal growth, premature birth, reduced birthweight, and congenital defects. Such infants require lengthier hospital stays necessitating rising health care costs, and they are at greater risk for neurobehavioral and other diseases. Thus, it is essential to understand the genesis of such disorders. As the primary communication organ between mother and conceptus, the placenta itself is susceptible to opioid effects but may be key to understanding how these drugs affect long-term offspring health and potential avenue to prevent later diseases. In this review, we will consider the evidence that placental responses are regulated through an endogenous opioid system. However, maternal consumption of opioid drugs can also bind and act through opioid receptors express by trophoblast cells of the placenta. Thus, we will also discuss the current human and rodent studies that have examined the effects of opioids on the placenta. These drugs might affect placental hormones associated with maternal recognition of pregnancy, including placental lactogens and human chorionic gonadotropin in rodents and humans, respectively. A further understanding of how such drugs affect the placenta may open up new avenues for early diagnostic and remediation approaches.

Whole Transcriptome Sequencing of Peripheral Blood Shows That Immunity/GnRH/PI3K-Akt Pathways Are Associated With Opioid Use Disorder

BACKGROUND

Opioid use disorder (OUD), which is most commonly exhibited as addiction, is a persistent chronic disease that places a burden on families and society. Various peripheral traits have been linked to OUD in the past, but research on this topic is insufficient.

METHODS

Seven male patients with OUD and 7 male healthy controls with matched demographic and clinical data were enrolled in this study. Peripheral blood RNA was used to construct an rRNA-removed library and a small RNA library. The peripheral transcriptomic differences between the two groups were investigated using RNA-seq. Differentially expressed messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs) were identified by bioinformatics methods, and functional enrichment analysis with differentially expressed RNAs was performed to investigate the potential biological mechanisms of OUD.

RESULTS

A total of 229 mRNAs (115 upregulated, 114 downregulated), 416 lncRNAs (191 upregulated, 225 downregulated), 17 circRNAs (16 upregulated, 1 downregulated) and 74 miRNAs (42 upregulated, 32 downregulated) were differentially expressed between the OUD group and the healthy control group. Functional enrichment analysis with differentially expressed mRNAs showed that immunity, GnRH secretion, and PI3K-Akt signaling pathways were associated with OUD. Immunity-, JAK-STAT-, and insulin-related pathways were enriched in functional enrichment analysis of target genes predicted by differentially expressed miRNAs.

CONCLUSION

We identified hundreds of differentially expressed genes that were enriched in immunity, GnRH secretion and PI3K-Akt signaling pathways. Some genes with significant changes might be used as potential biomarkers for progression and treatment of OUD.

The biochemical diagnosis of adrenal insufficiency with modern cortisol assays: Reappraisal in the setting of opioid exposure and hospitalization

OBJECTIVE

We aimed to (1) examine the diagnosis of opioid-induced adrenal insufficiency, and (2) investigate the diagnostic value of a morning cortisol <83 nmol/L (3 µg/dl) for the diagnosis of adrenal insufficiency, using newer more specific cortisol assays and cut-offs.

DESIGN

Retrospective study (5/2015-10/2020).

PARTICIPANTS

Cohort 1 (N = 75): adults who underwent cosyntropin stimulation testing and opioid exposure for >30 days. Cohort 2 (N = 854): adults, with or without opioid exposure, who had a morning cortisol level measured the same day as stimulation testing.

MEASUREMENTS

Peak cortisol during cosyntropin stimulation testing. Sensitivity and specificity of morning serum cortisol for adrenal insufficiency.

RESULTS

The prevalence of adrenal insufficiency in patients with chronic opioid exposure who underwent cosyntropin stimulation testing was 4.0% using a cortisol cutoff of <405 nmol/L (14.7 µg/dl) versus 19% using the traditional cutoff of <500 nmol/L (18.1 µg/dl). For hospitalized patients with and without opioid-exposure, 14 of 22 (64%) patients with morning cortisol levels of <83 nmol/L (3 µg/dl) passed cosyntropin stimulation testing. A morning cortisol level of <348 nmol/L (12.6 µg/dl) had 100% sensitivity (95% confidence interval: 84.5%-100%) for the diagnosis of adrenal insufficiency.

CONCLUSION

Applying a cutoff of <405 nmol/L (14.7 µg/dl), opioid-induced adrenal insufficiency is rare. Nearly 1 out of 6 patients would be reclassified as having adrenal insufficiency applying the guideline-recommended cutoff of <500 nmol/L (18.1 µg/dl). Serum morning cortisol <83 nmol/L (3 µg/dl) is not a valid diagnostic test for adrenal insufficiency in hospitalized patients, whether or not receiving opioids.

Testicular Tissue Banking for Fertility Preservation in Young Boys: Which Patients Should Be Included?

Due to the growing number of young patients at risk of germ cell loss, there is a need to preserve spermatogonial stem cells for patients who are not able to bank spermatozoa. Worldwide, more and more clinics are implementing testicular tissue (TT) banking programs, making it a novel, yet indispensable, discipline in the field of fertility preservation. Previously, TT cryopreservation was predominantly offered to young cancer patients before starting gonadotoxic chemo- or radiotherapy. Nowadays, most centers also bank TT from patients with non-malignant conditions who need gonadotoxic conditioning therapy prior to hematopoietic stem cell (HSCT) or bone marrow transplantation (BMT). Additionally, some centers include patients who suffer from genetic or developmental disorders associated with prepubertal germ cell loss or patients who already had a previous round of chemo- or radiotherapy. It is important to note that the surgical removal of TT is an invasive procedure. Moreover, TT cryopreservation is still considered experimental as restoration methods are not yet clinically available. For this reason, TT banking should preferably only be offered to patients who are at significant risk of becoming infertile. In our view, TT cryopreservation is recommended for young cancer patients in need of high-risk chemo- and/or radiotherapy, regardless of previous low-risk treatment. Likewise, TT banking is advised for patients with non-malignant disorders such as sickle cell disease, beta-thalassemia, and bone marrow failure, who need high-risk conditioning therapy before HSCT/BMT. TT retrieval during orchidopexy is also proposed for patients with bilateral cryptorchidism. Since patients with a medium- to low-risk treatment generally maintain their fertility, TT banking is not advised for this group. Also for Klinefelter patients, TT banking is not recommended as it does not give better outcomes than a testicular sperm extraction later in life.

The occurrence of opioid compounds in wastewater treatment plants and their receiving water bodies in Gauteng province, South Africa

The continuous influx of opioid compounds into aquatic environments has become an increasing and persistent concern, due to their extensive use. This is especially alarming as wastewater treatment plants (WWTPs) are unable to completely remove them. Despite the reported health concerns, the occurrence of opioid compounds in the environment has not received much attention. The present study investigates the occurrence of 19 opioids in four WWTPs and their respective receiving water bodies. All wastewater samples revealed opioids at concentration ranging from ng/L to μg/L with most influents having higher concentrations than effluents. WWTPs appeared to perform poorly (p > 0.05 between influents and effluents), and were unable to remove some opioids including Methadone (-27.3%) from the Leeuwkuil WWTP, Codeine (-21.7%) and Thebaine (-3.77%) from the Sandspruit WWTP, and Hydrocodone (-1.06%) from the Meyerton WWTP, respectively. Samples collected from the Leeuwkuil WWTP were the most contaminated, with eighteen out of nineteen opioid analogues exceeding 1 μg/L. Upstream surface water contained less opioids (most < LOQ) than downstream (p < 0.05), with Hydrocodone, Oxycodone, Hydromorphone, Fentanyl, Ketamine and Dihydrocodeine not detected. The occurrence of high concentrations of opioid analogues in downstream surface water (298 ng/L -10.8 μg/L for Klip River, 4.49 ng/L -13.1 μg/L for Vaal River, 70.5 ng/L -10.0 μg/L for Soutspruit River and 8.0 ng/L - 2.43 μg/L for Sun Spruit River) was directly linked to their mass loads in the respective wastewater effluent samples.

Wonder or evil?: Multifaceted health hazards and health benefits of Cannabis sativa and its phytochemicals

Cannabis sativa, widely known as 'Marijuana' poses a dilemma for being a blend of both good and bad medicinal effects. The historical use of Cannabis for both medicinal and recreational purposes suggests it to be a friendly plant. However, whether the misuse of Cannabis and the cannabinoids derived from it can hamper normal body physiology is a focus of ongoing research. On the one hand, there is enough evidence to suggest that misuse of marijuana can cause deleterious effects on various organs like the lungs, immune system, cardiovascular system, etc. and also influence fertility and cause teratogenic effects. However, on the other hand, marijuana has been found to offer a magical cure for anorexia, chronic pain, muscle spasticity, nausea, and disturbed sleep. Indeed, most recently, the United Nations has given its verdict in favour of Cannabis declaring it as a non-dangerous narcotic. This review provides insights into the various health effects of Cannabis and its specialized metabolites and indicates how wise steps can be taken to promote good use and prevent misuse of the metabolites derived from this plant.

Gonadotoxic effect of tramadol administration: A prospective controlled study

Objective

To detect the possible gonadotoxic effects of tramadol dependence on seminal fluid parameters, and prolactin and testosterone hormone levels.

Patients, Subjects, and Methods

There were 94 participants who were divided into a tramadol-dependent group (T-group; 56 patients) and a control group (C-group; 38 healthy volunteers). The following variables were evaluated: testosterone level, prolactin level, erectile function, libido, semen parameters, and effect of tramadol dose and dependence duration.

Results

There was a significant increase in erectile dysfunction (ED) and decreased libido in the T-group vs C-group. Also, the serum testosterone level was lower in the T-group vs the C-group, while the serum prolactin level was significantly higher in the T-group vs the C-group. All semen parameters were low in the T-group except for abnormal forms, which were high. As the dose of tramadol increased there was a more negative effect on the previous parameter, while ED, libido, semen volume and concentration showed no significant changes. When comparing tramadol doses of 400–1000 mg/day to >1000 mg/day, the tramadol blood level increased with high doses, while serum testosterone level decreased when the dose increased and the prolactin level increased when the dose increased. Progressive motility of the sperm decreased and abnormal forms increased. Also increased duration of tramadol administration was also accompanied by a more negative effect on these parameters

Conclusion

Tramadol administration has a negative effect on hormone levels, libido, erectile function, and semen characters.Abbreviations: ED: erectile dysfunction; EF: erectile function

Vitamin B12 ameliorate Tramadol-induced oxidative stress, endocrine imbalance, apoptosis and NO/iNOS/NF-κB expression in Sprague Dawley rats through regulatory mechanism in the pituitary-gonadal axis

This study aimed at the effect of vitamin B₁₂ (VB₁₂) on tramadol (TRM) induced pituitary-gonadal Axis toxicity. Thirty-two (32) adult male rats were randomized into four groups of eight (n = 8) rats each. Group A served as control was given 1 mL normal saline, group B received 50 mg /kg bwt TRM, group C received 0.5 mg/kg bwt VB₁₂ and group D received 50 mg /kg bwt TRM and 0.5 mg/kg bwt VB₁₂ through gastric gavage daily for 8 weeks. Parameters tested include sperm parameter, male reproductive hormone, testicular histology, glucose, lactate dehydrogenase (LDH), acid phosphate (ACP), and alkaline phosphate (ALP) activity, steroidogenic protein, cytochrome P450 A1, nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), nuclear factor- kappa B (NF-κB), oxidative and antioxidant makers. Tramadol significantly decreases sperm quality, hormone, steroidogenic protein, cytochrome P450 A1, ACP, ALP, and increases glucose, LDH, oxidative stress, mtTFA, and UCP2, p53 expression, NO, iNOS, NF-κB, IL-1β, IL-6, TNF-α, and caspase-3 activity. Degenerative alterations of the testes' and pituitary architecture and perturbation of spermatogenesis were observed in TRM-treated rats. The intervention of VB₁₂ downregulated testicular oxidative stress, inflammatory markers, glucose, lactate, LDH, p53, caspase-3, mtTFA, and UCP2. And upregulate antioxidant, sperm quality, hormone, and spermatogenic cells. Vitamin B₁₂ exhibited mitigation against TRM-induced testicular dysfunction via its antioxidant, anti-inflammatory and anti-apoptotic effects.

Dysregulation of the Hypothalamic-Pituitary-Testicular Axis due to Energy Deficit

CONTEXT

Although gonadal axis dysregulation from energy deficit is well recognized in women, the effects of energy deficit on the male gonadal axis have received much less attention.

EVIDENCE ACQUISITION

To identify relevant articles, we conducted PubMed searches from inception to May 2021.

EVIDENCE SYNTHESIS

Case series and mechanistic studies demonstrate that energy deficit (both acutely over days or chronically over months) either from inadequate energy intake and/or excessive energy expenditure can lower serum testosterone concentration as a result of hypothalamic-pituitary-testicular (HPT) axis dysregulation in men. The extent to which this has clinical consequences that can be disentangled from the effects of nutritional insufficiency, concomitant endocrine dysregulation (eg, adrenal and thyroid axis), and coexisting comorbidities (eg, depression and substance abuse) is uncertain. HPT axis dysfunction is primarily the result of loss of GnRH pulsatility resulting from a failure of leptin to induce kisspeptin signaling. The roles of neuroendocrine consequences of depression, hypothalamic-pituitary-adrenal axis activation, proinflammatory cytokines, Ghrelin, and genetic susceptibility remain unclear. In contrast to hypogonadism from organic pathology of the HPT axis, energy deficit-associated HPT dysregulation is functional, and generally reversible by restoring energy balance.

CONCLUSIONS

The clinical management of such men should aim to restore adequate nutrition and achieve and maintain a healthy body weight. Psychosocial comorbidities must be identified and addressed. There is no evidence that testosterone treatment is beneficial. Many knowledge gaps regarding epidemiology, pathophysiology, and treatment remain and we highlight several areas that require future research.

Complementary Role of Oxytocin and Vasopressin in Cardiovascular Regulation

The neurons secreting oxytocin (OXY) and vasopressin (AVP) are located mainly in the supraoptic, paraventricular, and suprachiasmatic nucleus of the brain. Oxytocinergic and vasopressinergic projections reach several regions of the brain and the spinal cord. Both peptides are released from axons, soma, and dendrites and modulate the excitability of other neuroregulatory pathways. The synthesis and action of OXY and AVP in the peripheral organs (eye, heart, gastrointestinal system) is being investigated. The secretion of OXY and AVP is influenced by changes in body fluid osmolality, blood volume, blood pressure, hypoxia, and stress. Vasopressin interacts with three subtypes of receptors: V1aR, V1bR, and V2R whereas oxytocin activates its own OXTR and V1aR receptors. AVP and OXY receptors are present in several regions of the brain (cortex, hypothalamus, pons, medulla, and cerebellum) and in the peripheral organs (heart, lungs, carotid bodies, kidneys, adrenal glands, pancreas, gastrointestinal tract, ovaries, uterus, thymus). Hypertension, myocardial infarction, and coexisting factors, such as pain and stress, have a significant impact on the secretion of oxytocin and vasopressin and on the expression of their receptors. The inappropriate regulation of oxytocin and vasopressin secretion during ischemia, hypoxia/hypercapnia, inflammation, pain, and stress may play a significant role in the pathogenesis of cardiovascular diseases.