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BioRxiv : the Preprint Server For... May 202430% of people in the United States have diabetes or pre-diabetes. Many of these individuals will develop diabetic neuropathy as a comorbidity, which is often treated...
30% of people in the United States have diabetes or pre-diabetes. Many of these individuals will develop diabetic neuropathy as a comorbidity, which is often treated with exogenous opioids like morphine, oxycodone, or tramadol. Although these opioids are effective analgesics, growing evidence indicates that they may directly impact the endocrine pancreas function in human and preclinical models. One common feature of these exogenous opioid ligands is their preference for the mu opioid receptor (MOPR), so we aimed to determine if endogenous MOPRs directly regulate pancreatic islet metabolism and hormone secretion. We show that pharmacological antagonism of MOPRs enhances glucagon secretion, but not insulin secretion, from human islets under high glucose conditions. This increased secretion is accompanied by increased cAMP signaling. mRNA expression of MOPRs is enriched in human islet α-cells, but downregulated in T2D islet donors, suggesting a link between metabolism and MOPR expression. Conditional genetic knockout of MOPRs in murine α-cells increases glucagon secretion in high glucose conditions without increasing glucagon content. Consistent with downregulation of MOPRs during metabolic disease, conditional MOPR knockout mice treated with a high fat diet show impaired glucose tolerance, increased glucagon secretion, increased insulin content, and increased islet size. Finally, we show that MOPR-mediated changes in glucagon secretion are driven, in part, by K channel activity. Together, these results demonstrate a direct mechanism of action for endogenous opioid regulation of endocrine pancreas.
PubMed: 38798528
DOI: 10.1101/2024.05.13.593899 -
BioRxiv : the Preprint Server For... Apr 2024Opioid use disorder is heritable, yet its genetic etiology is largely unknown. Analysis of addiction model traits in rodents (e.g., opioid behavioral sensitivity and...
Opioid use disorder is heritable, yet its genetic etiology is largely unknown. Analysis of addiction model traits in rodents (e.g., opioid behavioral sensitivity and withdrawal) can facilitate genetic and mechanistic discovery. C57BL/6J and C57BL/6NJ substrains have extremely limited genetic diversity, yet can show reliable phenotypic diversity which together, can facilitate gene discovery. The C57BL/6NJ substrain was less sensitive to oxycodone (OXY)-induced locomotor activity compared to the C57BL/6J substrain. Quantitative trait locus (QTL) mapping in an F2 cross identified a distal chromosome 1 QTL explaining 7-12% of the variance in OXY locomotor sensitivity and anxiety-like withdrawal in the elevated plus maze. We identified a second QTL for withdrawal on chromosome 5 near the candidate gene Gabra2 (alpha-2 subunit of GABA-A receptor) explaining 9% of the variance. Next, we generated recombinant lines from an F2 founder spanning the distal chromosome 1 locus (163-181 Mb), captured the QTL for OXY sensitivity and withdrawal, and fine-mapped a 2.45-Mb region (170.16-172.61 Mb). There were five striatal cis-eQTL transcripts in this region (Pcp4l1, Ncstn, Atp1a2, Kcnj9, Igsf9), two of which were confirmed at the protein level (KCNJ9, ATP1A2). Kcnj9, a.k.a., GIRK3, codes for a potassium channel that is a major effector of mu opioid receptor signaling. Atp1a2 codes for a subunit of a Na+/K+ ATPase enzyme that regulates neuronal excitability and shows adaptations following chronic opioid administration. To summarize, we identified genetic sources of opioid behavioral differences in C57BL/6 substrains, two of the most widely and often interchangeably used substrains in opioid addiction research.
PubMed: 38798314
DOI: 10.1101/2024.04.16.589731 -
Journal of Personalized Medicine May 2024Severe cancer pain substantially affects patients' quality of life, increasing the burden of the disease and reducing the disability-adjusted life years. Although opioid... (Review)
Review
Severe cancer pain substantially affects patients' quality of life, increasing the burden of the disease and reducing the disability-adjusted life years. Although opioid analgesics are effective, they may induce opioid-induced bowel dysfunction (OIBD). Oxycodone/naloxone combination therapy has emerged as a promising approach to mitigate opioid-induced constipation (OIC) while providing effective pain relief. This review provides an updated analysis of the literature of the last decade regarding the use of oxycodone/naloxone in the management of severe cancer pain. Through a comprehensive search of databases, studies focusing on the efficacy, safety, and patient experience of oxycodone/naloxone's prolonged release in severe cancer pain management were identified. Furthermore, the literature discusses the mechanism of action of naloxone in mitigating OIC without compromising opioid analgesia. Overall, the evidence suggests that oxycodone/naloxone combination therapy offers a valuable option for effectively managing severe cancer pain while minimizing opioid-induced constipation, thereby improving patients' quality of life. However, further research is needed to optimize dosing regimens, evaluate long-term safety, and assess patient outcomes in diverse cancer populations.
PubMed: 38793067
DOI: 10.3390/jpm14050483 -
Molecular Pharmacology May 2024Opioid analgesics are widely used as a treatment option for pain management and relief. However, the misuse of opioid analgesics has contributed to the current opioid...
Opioid analgesics are widely used as a treatment option for pain management and relief. However, the misuse of opioid analgesics has contributed to the current opioid epidemic in the United States. Prescribed opioids such as morphine, codeine, oxycodone, and fentanyl are mu-opioid receptor (MOR) agonists primarily used in the clinic to treat pain or during medical procedures, but development of tolerance limits their utility for treatment of chronic pain. Here we explored the effects of biasing Gβγ-signaling on tolerance development following chronic morphine treatment We hypothesized that biasing Gβγ-signaling with gallein could prevent activation of regulatory signaling pathways that result in tolerance to antinociceptive effects of MOR agonists. Gallein has been shown to bind to Gβγ and inhibit interactions of Gβγ with PLCβ3 or GRK2 but not GIRK channels. In mice, morphine-induced antinociception was evaluated in the 55{degree sign}C warm water tail withdrawal assay. We used two paradigms for gallein treatment: administration during and after 3x daily morphine administration. Our results show that gallein cotreatment during repeated administration of morphine decreased opioid tolerance development, and gallein treatment in an opioid-tolerant state enhanced the potency of morphine. Mechanistically, our data suggest that PLCβ3 is necessary for potentiating effects of gallein in an opioid-tolerant state but not in preventing the development of tolerance. These studies demonstrate that small molecules that target Gβγ-signaling could reduce the need for large doses of opioid analgesics to treat pain by producing an opioid-sparing effect. Biasing Gβγ-signaling prevents tolerance to repeated morphine administration and potentiates the antinociceptive effects of morphine in an opioid-tolerant state. Mechanistically, PLCβ is necessary for potentiating effects of gallein in an opioid-tolerant state but not in preventing the development of tolerance. This study identifies a novel treatment strategy to decrease the development of tolerance to the analgesic effects of MOR agonists, which are necessary to improve pain treatment and decrease the incidence of OUD.
PubMed: 38769020
DOI: 10.1124/molpharm.124.000875 -
Orthopaedic Journal of Sports Medicine May 2024Although several studies have noted that patients are routinely overprescribed opioids, few have reported usage after arthroscopic surgery.
BACKGROUND
Although several studies have noted that patients are routinely overprescribed opioids, few have reported usage after arthroscopic surgery.
PURPOSE
To determine opioid consumption and allocation for unused opioids after common arthroscopic surgeries.
STUDY DESIGN
Case series; Level of evidence, 4.
METHODS
Patients between the ages of 15 and 40 years who were scheduled to undergo anterior cruciate ligament reconstruction (ACLR), labral repair of the hip or shoulder, meniscectomy, or meniscal repair were prospectively enrolled. Patients were prescribed either 5 mg hydrocodone-325 mg acetaminophen or 5 mg oxycodone-325 mg acetaminophen based on surgeon preference. Patients completed a daily opioid usage survey during the 2-week postoperative period. In addition, patients completed a survey on postoperative day 21 inquiring about continued opioid use and medication disposal, if applicable. Opioid medication consumption was converted to morphine milligram equivalents (MMEs).
RESULTS
Of the 200 patients who were enrolled in the study, 176 patients had sufficient follow-up after undergoing 85 (48%) ACLR, 26 (14.8%) hip labral repair, 34 (19.3%) shoulder labral repair, 18 (10.2%) meniscectomy, and 13 (7.4%) meniscal repair procedures. Mean age was 26.1 years (SD, 7.38); surgeons prescribed a mean of 26.6 pills whereas patients reported consuming a mean of 15.5 pills. The mean MME consumption in the 14 days after each procedure was calculated: ACLR (95.7; 44% of prescription), hip labral repair (84.8; 37%), shoulder labral repair (57.2; 35%), meniscectomy (18.4; 27%), and meniscal repair (32.1; 42%). This corresponded to approximately 39% of the total opioid prescription being utilized across all procedures. Mean MME consumption was greatest on postoperative day 1 in hip, shoulder, and meniscal procedures and on postoperative day 2 in ACLR. Only 7.04% of patients reported continued opioid use in the third postoperative week. Patients had a mean of 11 unused pills or 77.7 MMEs remaining. Of the patients with remaining medication, 24.7% intended to keep their medication for future use.
CONCLUSION
The results of our study indicate that patients who undergo the aforementioned arthroscopic procedures consume <75 MMEs in the 2-week postoperative period, translating into a mean of 10 to 15 pills consumed. Approximately 60% of total opioids prescribed went unused, and one-fourth of patients intended to keep their remaining medication for future usage. We have provided general prescribing guidelines and recommend that surgeons carefully consider customizing their opioid prescriptions on the basis of procedure site to balance optimal postoperative analgesia with avoidance of dissemination of excess opioids.
PubMed: 38757068
DOI: 10.1177/23259671241249688 -
Gynecologic Oncology Reports Jun 2024Across specialties, surgeons over-prescribe opioids to patients after surgery. We aimed to develop and implement an evidence-based calculator to inform post-discharge...
INTRODUCTION
Across specialties, surgeons over-prescribe opioids to patients after surgery. We aimed to develop and implement an evidence-based calculator to inform post-discharge opioid prescription size for gynecologic oncology patients after laparotomy.
METHODS
In 2021, open surgical gynecologic oncology patients were called 2-4 weeks after surgery to ask about their home opioid use. This data was used to develop a calculator for post-discharge opioid prescription size using two factors: 1) age of the patient, 2) oral morphine equivalents (OME) used by patients the day before hospital discharge. The calculator was implemented on the inpatient service from 8/21/22 and patients were contacted 2-4 weeks after surgery to again assess their opioid use at home.
RESULTS
Data from 95 surveys were used to develop the opioid prescription size calculator and are compared to 95 post-intervention surveys. There was no difference pre- to post-intervention in demographic data, surgical procedure, or immediate postoperative recovery. The median opioid prescription size decreased from 150 to 37.5 OME (p < 0.01) and self-reported use of opioids at home decreased from 22.5 to 7.5 OME (p = 0.05). The refill rate did not differ (12.6 % pre- and 11.6 % post-intervention, p = 0.82). The surplus of opioids our patients reported having at home decreased from 1264 doses of 5 mg oxycodone tabs in the pre-intervention cohort, to 490 doses in the post-intervention cohort, a 61 % reduction.
CONCLUSIONS
An evidence-based approach for prescribing opioids to patients after laparotomy decreased the surplus of opioids we introduced into our patients' communities without impacting refill rates.
PubMed: 38725997
DOI: 10.1016/j.gore.2024.101396 -
Anesthesiology and Pain Medicine Feb 2024Total hip replacement (THR) is frequently associated with intense post-surgical pain. Effective pain management is of crucial importance to improving patient's condition...
BACKGROUND
Total hip replacement (THR) is frequently associated with intense post-surgical pain. Effective pain management is of crucial importance to improving patient's condition and increasing his/her satisfaction in the post-operative time.
OBJECTIVES
This study aimed to compare the analgesic effect and safety of oxycodone and fentanyl after THR.
METHODS
Seventy-two cases scheduled for elective THR were included in this randomized, triple-blind trial. The patients were equally randomized into 2 groups: Fentanyl group (50 ug of fentanyl) and oxycodone group (oxycodone 4 mg). Drugs were received 20 min prior to the end of the operation.
RESULTS
Post-operative visual analog scale (VAS) measurements at rest and movement at the post-anesthesia care unit (PACU) and in the ward, 2 h, 4 h, and 8 h post-operatively exhibited a significantly reduced value in the oxycodone group compared to the fentanyl group (P-value < 0.05). Time to first rescue for analgesia was delayed significantly in the oxycodone compared to the fentanyl group (P-value < 0.001). Fentanyl consumption (ug) in the 1st post-operative 12 h, 24 h, and 48 h decreased significantly in the oxycodone group compared to the fentanyl group (P-value < 0.001). Post-operative nausea, vomiting, headache, and pruritus were matched between the 2 groups (P > 0.05).
CONCLUSIONS
A bolus dose of 4 mg of oxycodone provided superior analgesic efficacy than 50 ug fentanyl as evidenced by significantly lower pain score, delayed onset to first request for analgesia, and the smaller amount of fentanyl consumption at 12, 24, and 48 h post-total hip arthroplasty compared to fentanyl. The incidence of adverse events was comparable between the 2 groups.
PubMed: 38725916
DOI: 10.5812/aapm-142710 -
Frontiers in Surgery 2024We aimed to compare the anesthesia induction effects of oxycodone and sufentanil on postoperative pain in patients undergoing laparoscopic gallbladder-preserving...
Comparison of the analgesic effects of oxycodone vs. sufentanil on postoperative pain after laparoscopic gallbladder-preserving cholecystolithotomy: a prospective randomized controlled trial.
BACKGROUND
We aimed to compare the anesthesia induction effects of oxycodone and sufentanil on postoperative pain in patients undergoing laparoscopic gallbladder-preserving cholecystolithotomy, as well as changes in serum levels of inflammatory factors (TNF-α, IL-6, and IL-10) in the perioperative period.
METHODS
Sixty patients who underwent laparoscopic gallbladder-preserving cholecystolithotomy were evenly divided into oxycodone (O) and sufentanil (S) groups. In groups O and S, oxycodone (0.3 mg/kg) and sufentanil (0.3 ug/kg) were administered, respectively, followed by propofol (2 mg/kg) and rocuronium (0.6 mg/kg). In both groups, the intraoperative electroencephalography double-frequency index was used to guide the use of sedative and analgesic drugs, assessing the follow-up analgesic effect (VAS), degree of sedation (Ramsey), and postoperative complications at seven different time points (0, 0.5, 2, 4, 6, 8, and 24 h postoperatively).
RESULTS
Compared with the S group, patients in the O group exhibited lower VAS scores within 24 h postoperatively ( < 0.001), but there was no statistical difference between wound and shoulder pain scores (> 0.05). Regarding postoperative awakening and extubation duration, O group patients experienced shorter times and better remedial analgesia ( < 0.05). In terms of the degree of sedation, the Ramsay score decreased at 0 h postoperatively compared with the S group ( < 0.001).
CONCLUSION
Compared with sufentanil, oxycodone anesthesia induced better postoperative analgesia and less inflammatory responses in patients undergoing laparoscopic gallbladder-preserving cholecystolithotomy.
CLINICAL TRIAL REGISTRATION
This study has been approved by the Ethics Committee of Peking University Shougang Hospital, with ethical approval (No. IRBK-2020-009), and has completed registration in the Chinese Clinical Trials Register (http://www.chictr.org.cn/) (ChiCTR2000031230).
PubMed: 38721023
DOI: 10.3389/fsurg.2024.1382759 -
The Journal of Innovations in Cardiac... Apr 2024Providing adequate analgesia perioperatively during subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation can be a challenge. The objective of our...
Providing adequate analgesia perioperatively during subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation can be a challenge. The objective of our study was to assess the efficacy and safety of the erector spinae plane (ESP) block technique in providing analgesia and minimizing the risk of opioid use in high-risk patient populations. We enrolled consecutive patients >18 years of age undergoing S-ICD implantation from February 2020 to February 2022 at our center prospectively. Patients were randomly assigned to receive the ESP block or traditional wound infiltration. A total of 24 patients were enrolled, including 13 patients randomized to ESP block and 11 patients as controls who received only wound infiltration. The primary outcome assessed was the overall use of perioperative analgesic medications in the ESP block group versus the surgical wound infiltration group. A significant reduction in intraoperative fentanyl use was observed [median ([interquartile range]) in the ESP block group (0 [0-50] μg) compared to the wound infiltration block group (75 [50-100] μg) ( = .001). The overall postoperative day (POD) 0 fentanyl use was also significantly decreased (75 [50-100] μg) in the ESP block group compared to the surgical wound infiltration group (100 [87.5-150] μg) ( = .049). There was also a trend of decreased POD 0 oxycodone-acetaminophen use. Finally, the number of days to discharge was less in the ESP block group. These results indicate that ESP block is an innovative, safe, and effective technique that decreases intraoperative and postoperative opioid consumption and may be a useful adjunct pain-management technique in these high-risk patients. Larger studies are needed to further validate its use.
PubMed: 38715552
DOI: 10.19102/icrm.2024.15043