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International Journal of Nanomedicine 2024Opioids are irreplaceable analgesics owing to the lack of alternative analgesics that offer opioid-like pain relief. However, opioids have many undesirable central side...
BACKGROUND
Opioids are irreplaceable analgesics owing to the lack of alternative analgesics that offer opioid-like pain relief. However, opioids have many undesirable central side effects. Restricting opioids to peripheral opioid receptors could reduce those effects while maintaining analgesia.
METHODS
To achieve this goal, we developed Tet1-LNP (morphine), a neural-targeting lipid nanoparticle encapsulating morphine that could specifically activate the peripheral opioid receptor in the dorsal root ganglion (DRG) and significantly reduce the side effects caused by the activation of opioid receptors in the brain. Tet1-LNP (morphine) were successfully prepared using the thin-film hydration method. In vitro, Tet1-LNP (morphine) uptake was assessed in differentiated neuron-like PC-12 cells and dorsal root ganglion (DRG) primary cells. The uptake of Tet1-LNP (morphine) in the DRGs and the brain was assessed in vivo. Von Frey filament and Hargreaves tests were used to assess the antinociception of Tet1-LNP (morphine) in the chronic constriction injury (CCI) neuropathic pain model. Morphine concentration in blood and brain were evaluated using ELISA.
RESULTS
Tet1-LNP (morphine) had an average size of 131 nm. Tet1-LNP (morphine) showed high cellular uptake and targeted DRG in vitro. CCI mice treated with Tet1-LNP (morphine) experienced prolonged analgesia for nearly 32 h compared with 3 h with free morphine ( < 0.0001). Notably, the brain morphine concentration in the Tet1-LNP (morphine) group was eight-fold lower than that in the morphine group ( < 0.0001).
CONCLUSION
Our study presents a targeted lipid nanoparticle system for peripheral neural delivery of morphine. We anticipate Tet1-LNP (morphine) will offer a safe formulation for chronic neuropathic pain treatment, and promise further development for clinical applications.
Topics: Animals; Morphine; Ganglia, Spinal; Nanoparticles; Rats; PC12 Cells; Analgesics, Opioid; Male; Neuralgia; Mice; Lipids; Proto-Oncogene Proteins; Peripheral Nerves; Mixed Function Oxygenases; DNA-Binding Proteins; Liposomes
PubMed: 38828199
DOI: 10.2147/IJN.S453608 -
Drug Design, Development and Therapy 2024Oxycodone is a potent μ- and κ-opioid receptor agonist that can relieve both somatic and visceral pain. We assessed oxycodone- vs sufentanil-based multimodal analgesia... (Randomized Controlled Trial)
Randomized Controlled Trial Clinical Trial
PURPOSE
Oxycodone is a potent μ- and κ-opioid receptor agonist that can relieve both somatic and visceral pain. We assessed oxycodone- vs sufentanil-based multimodal analgesia on postoperative pain following major laparoscopic gastrointestinal surgery.
METHODS
In this randomised double-blind controlled trial, 40 adult patients were randomised (1:1, stratified by type of surgery) to receive oxycodone- or sufentanil-based multimodal analgesia, comprising bilateral transverse abdominis plane blocks, intraoperative dexmedetomidine infusion, flurbiprofen axetil, and oxycodone- or sufentanil-based patient-controlled analgesia. The co-primary outcomes were time-weighted average (TWA) of visceral pain (defined as intra-abdominal deep and dull pain) at rest and on coughing during 0-24 h postoperatively, assessed using the numerical rating scale (0-10) with a minimal clinically important difference of 1.
RESULTS
All patients completed the study (median age, 64 years; 65% male) and had adequate postoperative pain control. The mean (SD) 24-h TWA of visceral pain at rest was 1.40 (0.77) in the oxycodone group vs 2.00 (0.98) in the sufentanil group (mean difference=-0.60, 95% CI, -1.16 to -0.03; =0.039). Patients in the oxycodone group had a significantly lower 24-h TWA of visceral pain on coughing (2.00 [0.83] vs 2.98 [1.26]; mean difference=-0.98, 95% CI, -1.66 to -0.30; =0.006). In the subgroup analyses, the treatment effect of oxycodone vs sufentanil on the co-primary outcomes did not differ in terms of age (18-65 years or >65 years), sex (female or male), or type of surgery (colorectal or gastric). Secondary outcomes (24-h TWA of incisional and shoulder pain, postoperative analgesic usage, rescue analgesia, adverse events, and patient satisfaction) were comparable between groups.
CONCLUSION
For patients undergoing major laparoscopic gastrointestinal surgery, oxycodone-based multimodal analgesia reduced postoperative visceral pain in a statistically significant but not clinically important manner.
TRIAL REGISTRATION
Chinese Clinical Trial Registry (ChiCTR2100052085).
Topics: Humans; Oxycodone; Double-Blind Method; Middle Aged; Male; Female; Laparoscopy; Pain, Postoperative; Visceral Pain; Aged; Analgesics, Opioid; Adult; Digestive System Surgical Procedures; Dexmedetomidine; Sufentanil; Analgesia, Patient-Controlled; Flurbiprofen
PubMed: 38828025
DOI: 10.2147/DDDT.S464518 -
Drug Design, Development and Therapy 2024Mechanistic studies showed that morphine may impair the antiplatelet effect of P2Y12 inhibitors. However, Several clinical studies with cardiovascular events as an...
PURPOSE
Mechanistic studies showed that morphine may impair the antiplatelet effect of P2Y12 inhibitors. However, Several clinical studies with cardiovascular events as an outcome are contradictory, and the broader impact of this drug interaction on additional organ systems remains uncertain. With multisource data, this study sought to determine the effects of morphine interaction with P2Y12 inhibitors on major adverse outcomes comprehensively, and identify the warning indicators.
PATIENTS AND METHODS
Interaction signals were sought in 187,919 safety reports from the FDA Adverse Event Reporting System (FAERS) database, utilizing reporting odds ratios (repOR). In a cohort of 5240 acute coronary syndrome patients, the analyses were validated, and the biological effects of warning indicators were further studied with Mendelian randomization and mediation analysis.
RESULTS
Potential risk of renal system adverse events in patients cotreated with morphine is significantly higher in FAERS (repOR 4.83, 95% CI 4.42-5.28, false discovery rate adjusted- =3.55*10). The analysis of in-house patient cohorts validated these results with an increased risk of acute kidney injury (adjusted OR: 1.65; 95% CI: 1.20 to 2.26), and we also found a risk of myocardial infarction in patients treated with morphine (adjusted OR: 1.55; 95% CI: 1.14 to 2.11). The Morphine group exhibited diminished Plateletcrit (PCT) levels post-surgery and lower PCT levels were associated with an increased risk of AKI.
CONCLUSION
The administration of morphine in patients treated with P2Y12 receptor inhibitors should be carefully evaluated. PCT may serve as a potential warning indicator for morphine-related renal injury.
Topics: Humans; Morphine; Purinergic P2Y Receptor Antagonists; Acute Coronary Syndrome; Male; Female; Middle Aged; Aged; Platelet Aggregation Inhibitors; Analgesics, Opioid
PubMed: 38828024
DOI: 10.2147/DDDT.S458299 -
Therapeutic Advances in... 2024This case report examines the possible correlation between the clozapine/norclozapine ratio and the occurrence of constipation and paralytic ileus. We present the case...
This case report examines the possible correlation between the clozapine/norclozapine ratio and the occurrence of constipation and paralytic ileus. We present the case of a 42-year-old patient diagnosed with schizoaffective disorder undergoing clozapine therapy. Despite intensive treatment with clozapine, haloperidol, valproic acid and biweekly electroconvulsive therapy sessions for over a year, florid psychotic symptoms and fluctuating mood swings persisted. Therefore, valproic acid was replaced by carbamazepine, a potent inducer of several CYP450-enzymes. To maintain clozapine plasma levels, fluvoxamine, a CYP1A2-inhibitor, was introduced at a dose of 25 mg before this switch. After addition of carbamazepine, there was a significant decline in clozapine levels, necessitating an increase in fluvoxamine dosage to 50 mg. Five weeks later the patient was admitted to a general hospital with a diagnosis of paralytic ileus. Treatment with enemas proved effective. Drug concentration analysis revealed a 2.5-fold increase in norclozapine levels in the weeks preceding hospital admission, resulting in an inverted clozapine/norclozapine ratio. Treatment with clozapine, carbamazepine and fluvoxamine was continued as the patient demonstrated clinical improvement on carbamazepine. Concurrently, an intensive laxative regimen was initiated. Two weeks later, the patient was readmitted to the general hospital due to suspected paralytic ileus and faecal vomiting, once again displaying an inverted clozapine/norclozapine ratio. We discuss potential mechanisms contributing to the occurrence of the paralytic ileus in this patient, including the antagonism of muscarinic M3 receptors by both clozapine and norclozapine, as well as the agonism of delta-opioid receptors by norclozapine. This case highlights the potential significance of both the clozapine/norclozapine ratio and absolute norclozapine levels as risk factors for constipation and paralytic ileus in patients on clozapine therapy.
PubMed: 38827014
DOI: 10.1177/20451253241255487 -
The Pharmacogenomics Journal Jun 2024The aim was to determine if opioid neuroimmunopharmacology pathway gene polymorphisms alter serum morphine, morphine-3-glucuronide and morphine-6-glucuronide...
The aim was to determine if opioid neuroimmunopharmacology pathway gene polymorphisms alter serum morphine, morphine-3-glucuronide and morphine-6-glucuronide concentration-response relationships in 506 cancer patients receiving controlled-release oral morphine. Morphine-3-glucuronide concentrations (standardised to 11 h post-dose) were higher in patients without pain control (median (interquartile range) 1.2 (0.7-2.3) versus 1.0 (0.5-1.9) μM, P = 0.006), whereas morphine concentrations were higher in patients with cognitive dysfunction (40 (20-81) versus 29 (14-60) nM, P = 0.02). TLR2 rs3804100 variant carriers had reduced odds (adjusted odds ratio (95% confidence interval) 0.42 (0.22-0.82), P = 0.01) of opioid adverse events. IL2 rs2069762 G/G (0.20 (0.06-0.52)), BDNF rs6265 A/A (0.15 (0.02-0.63)) and IL6R rs8192284 carrier (0.55 (0.34-0.90)) genotypes had decreased, and IL6 rs10499563 C/C increased (3.3 (1.2-9.3)), odds of sickness response (P ≤ 0.02). The study has limitations in heterogeneity in doses, sampling times and diagnoses but still suggests that pharmacokinetics and immune genetics co-contribute to morphine pain control and adverse effects in cancer patients.
Topics: Humans; Morphine; Male; Female; Cancer Pain; Middle Aged; Analgesics, Opioid; Delayed-Action Preparations; Aged; Pharmacogenetics; Polymorphism, Single Nucleotide; Morphine Derivatives; Adult; Pharmacogenomic Variants; Toll-Like Receptor 2
PubMed: 38824169
DOI: 10.1038/s41397-024-00339-w -
Pharmacological Research Jul 2024Targeting the CCL2/CCR2 chemokine axis has been shown to be effective at relieving pain in rodent models of inflammatory and neuropathic pain, therefore representing a...
Targeting the CCL2/CCR2 chemokine axis has been shown to be effective at relieving pain in rodent models of inflammatory and neuropathic pain, therefore representing a promising avenue for the development of non-opioid analgesics. However, clinical trials targeting this receptor for inflammatory conditions and painful neuropathies have failed to meet expectations and have all been discontinued due to lack of efficacy. To overcome the poor selectivity of CCR2 chemokine receptor antagonists, we generated and characterized the function of intracellular cell-penetrating allosteric modulators targeting CCR2, namely pepducins. In vivo, chronic intrathecal administration of the CCR2-selective pepducin PP101 was effective in alleviating neuropathic and bone cancer pain. In the setting of bone metastases, we found that T cells infiltrate dorsal root ganglia (DRG) and induce long-lasting pain hypersensitivity. By acting on CCR2-expressing DRG neurons, PP101 attenuated the altered phenotype of sensory neurons as well as the neuroinflammatory milieu of DRGs, and reduced bone cancer pain by blocking CD4 and CD8 T cell infiltration. Notably, PP101 demonstrated its efficacy in targeting the neuropathic component of bone cancer pain, as evidenced by its anti-nociceptive effects in a model of chronic constriction injury of the sciatic nerve. Importantly, PP101-induced reduction of CCR2 signaling in DRGs did not result in deleterious tumor progression or adverse behavioral effects. Thus, targeting neuroimmune crosstalk through allosteric inhibition of CCR2 could represent an effective and safe avenue for the management of chronic pain.
Topics: Animals; Receptors, CCR2; Chronic Pain; Ganglia, Spinal; Neuralgia; Humans; Cancer Pain; Bone Neoplasms; Analgesics; Male; Mice; Female; Mice, Inbred C57BL
PubMed: 38823470
DOI: 10.1016/j.phrs.2024.107242 -
Neurobiology of Disease Aug 2024Opioid system dysregulation in response to stress is known to lead to psychiatric disorders including major depression. Among three different types of opioid receptors,...
Opioid system dysregulation in response to stress is known to lead to psychiatric disorders including major depression. Among three different types of opioid receptors, the mu-type receptors (mORs) are highly expressed in the habenula complex, however, the action of mORs in this area and its interaction with stress exposure is largely unknown. Therefore, we investigated the roles of mORs in the habenula using male rats of an acute learned helplessness (aLH) model. First, we found that mOR activation decreased both excitatory and inhibitory synaptic transmission onto the lateral habenula (LHb). Intriguingly, this mOR-induced synaptic depression was reduced in an animal model of depression compared to that of controls. In naïve animals, we found an unexpected interaction between mORs and the endocannabinoid (eCB) signaling occurring in the LHb, which mediates presynaptic alteration occurring with mOR activation. However, we did not observe presynaptic alteration by mOR activation after stress exposure. Moreover, selective mOR activation in the habenula before, but not after, stress exposure effectively reduced helpless behaviors compared to aLH animals. Our observations are consistent with clinical reports suggesting the involvement of mOR signaling in depression, and additionally reveal a critical time window of mOR action in the habenula for ameliorating helplessness symptoms.
Topics: Animals; Habenula; Male; Receptors, Opioid, mu; Helplessness, Learned; Synaptic Transmission; Rats; Depression; Rats, Sprague-Dawley; Stress, Psychological; Disease Models, Animal
PubMed: 38821376
DOI: 10.1016/j.nbd.2024.106543 -
Drugs & Aging Jun 2024Most drugs have not been evaluated in the older population. Recognizing physiological alterations associated with changes in drug disposition and with the ultimate... (Review)
Review
Most drugs have not been evaluated in the older population. Recognizing physiological alterations associated with changes in drug disposition and with the ultimate effect, especially in central nervous system-acting drugs, is fundamental. While considering pharmacokinetics, it should be noted that the absorption of most drugs from the gastrointestinal tract does not change in advanced age. There are only few data about the effect of age on the transdermal absorption of medications such as fentanyl. Absorption from an intramuscular injection may be similar in older adults as in younger patients. The distribution of lipophilic drugs (such as diazepam) is increased owing to a relative increase in the percentage of body fat, causing drug accumulation and prolonged drug elimination following cessation. Phase I drug biotransformation is variably decreased in aging, impacting elimination, and hepatic drug clearance has been shown to decrease in older individuals by 10-40% for most drugs studied. Lower doses of phenothiazines, butyrophenones, atypical antipsychotics, antidepressants (citalopram, mirtazapine, and tricyclic antidepressants), and benzodiazepines (such as diazepam) achieve the same extent of exposure. For renally cleared drugs with no prior metabolism (such as gabapentin), the glomerular filtration rate appropriately estimates drug clearance. Important pharmacodynamic changes in older adults include an increased sedative effect of benzodiazepines at a given drug exposure, and a higher sensitivity to mu opiate receptor agonists and to opioid adverse effects. Artificial intelligence, physiologically based pharmacokinetic modeling and simulation, and concentration-effect modeling enabling a differentiation between the pharmacokinetic and the pharmacodynamic effects of aging might help to close some of the gaps in knowledge.
Topics: Humans; Aged; Central Nervous System Agents; Aging
PubMed: 38814377
DOI: 10.1007/s40266-024-01117-w -
Journal of Medicinal Chemistry Jun 2024Despite the availability of numerous pain medications, the current array of Food and Drug Administration-approved options falls short in adequately addressing pain...
Despite the availability of numerous pain medications, the current array of Food and Drug Administration-approved options falls short in adequately addressing pain states for numerous patients and consequently worsens the opioid crisis. Thus, it is imperative for basic research to develop novel and nonaddictive pain medications. Toward addressing this clinical goal, nalfurafine (NLF) was chosen as a lead and its structure-activity relationship (SAR) systematically studied through design, syntheses, and characterization of 24 analogues. Two analogues, and , showed longer durations of action than NLF in a warm-water tail immersion assay, produced effects primarily mediated by KOR and DOR, penetrated the blood-brain barrier, and did not function as reinforcers. Additionally, produced fewer sedative effects than NLF. Taken together, these results aid the understanding of NLF SAR and provide insights for future endeavors in developing novel nonaddictive therapeutics to treat pain.
Topics: Structure-Activity Relationship; Spiro Compounds; Animals; Morphinans; Mice; Male; Humans; Receptors, Opioid, kappa; Pain Management; Pain; Analgesics
PubMed: 38814086
DOI: 10.1021/acs.jmedchem.4c00646 -
PloS One 2024The vertebrate enteric nervous system (ENS) is a crucial network of enteric neurons and glia resident within the entire gastrointestinal tract (GI). Overseeing essential...
The vertebrate enteric nervous system (ENS) is a crucial network of enteric neurons and glia resident within the entire gastrointestinal tract (GI). Overseeing essential GI functions such as gut motility and water balance, the ENS serves as a pivotal bidirectional link in the gut-brain axis. During early development, the ENS is primarily derived from enteric neural crest cells (ENCCs). Disruptions to ENCC development, as seen in conditions like Hirschsprung disease (HSCR), lead to the absence of ENS in the GI, particularly in the colon. In this study, using zebrafish, we devised an in vivo F0 CRISPR-based screen employing a robust, rapid pipeline integrating single-cell RNA sequencing, CRISPR reverse genetics, and high-content imaging. Our findings unveil various genes, including those encoding opioid receptors, as possible regulators of ENS establishment. In addition, we present evidence that suggests opioid receptor involvement in the neurochemical coding of the larval ENS. In summary, our work presents a novel, efficient CRISPR screen targeting ENS development, facilitating the discovery of previously unknown genes, and increasing knowledge of nervous system construction.
Topics: Animals; Enteric Nervous System; Zebrafish; CRISPR-Cas Systems; Zebrafish Proteins; Neural Crest; Hirschsprung Disease
PubMed: 38809858
DOI: 10.1371/journal.pone.0303914