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PubMed2026

The analgesic efficacy of intrathecal morphine compared to peripheral regional analgesia in total hip arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Following elective total hip arthroplasty, pain continues to be a significant problem. Intrathecal morphine or peripheral regional analgesia, that is local infiltration analgesia or peripheral nerve block, are common analgesic modalities, but it is still not known which is superior. DESIGN: Systematic review and meta-analysis of randomised controlled trials. DATA SOURCES: The following electronic databases were searched from inception to 24 March 2026: CENTRAL; Ovid Embase; Ovid MEDLINE; Scopus; and Web of Science. ELIGIBILITY CRITERIA: Randomised controlled trials that compared intrathecal morphine to peripheral regional analgesia in patients scheduled for elective total hip arthroplasty under general or spinal anaesthesia. RESULTS: Eight trials and 471 patients were included. The peripheral regional analgesia was peripheral nerve block in six trials and local infiltration analgesia in two trials. No difference was demonstrated between intrathecal morphine and peripheral regional analgesia in regard to the first coprimary outcome, the pain score at rest at 24 h. The quality of evidence was moderate. Intrathecal morphine was found to be superior to peripheral regional analgesia with respect to the second coprimary outcome, the cumulative intravenous morphine equivalent consumption at 24 h. Mean difference (95% CI) was 11.38 mg (4.31-18.45; P  = 0.002, I2  = 81%). The quality of evidence was low. Intrathecal morphine was revealed to be superior to peripheral regional analgesia at 8-12 h for the pain score at rest, 1.24 (0.60-1.88); P  = 0.0001, I2  = 68%; pain score on movement, 1.15 (0.12-2.17), P  = 0.03, I2  = 65%; but the rate of in hospital pruritus was reduced with peripheral regional analgesia, 0.31 (0.17-0.58), P  = 0.0002, I2  = 0%. No differences in functional status were shown. CONCLUSIONS: We found no difference between intrathecal morphine and peripheral regional analgesia in regard to pain score at rest at 24 h. Intrathecal morphine may lead to a favourable effect on some but not all analgesic indices compared to peripheral regional analgesia in elective total hip arthroplasty. The quality of evidence for these positive effects was low. Intrathecal morphine reduced the systemic opioid consumption, but is not in itself an opioid free strategy. This notion is supported by the increased incidence of in hospital pruritus with intrathecal morphine. The quality of evidence for this was high. In view of the quality of evidence, high quality randomised controlled trials are required to substantiate these results.

Humans↗

PubMed2026

Comparison of analgesic efficacy of pericapsular group of nerve block versus anterior quadratus lumborum block in adult patients undergoing unilateral hip arthroplasty: A comparative randomized controlled trial.

BACKGROUND: Total hip arthroplasty is a painful surgical procedure; therefore, it is a challenge to manage effective pain control during the perioperative period. STUDY OBJECTIVES: We compared the analgesic efficacy of the pericapsular nerve group block and the anterior quadratus lumborum block in patients undergoing unilateral hip arthroplasty. DESIGN: Randomized controlled trial. SETTINGS: Operating room of a tertiary care center. PATIENTS: 92 adult patients of >18 years who underwent elective, unilateral total hip arthroplasty under spinal anesthesia were randomized to either Group P (USG guided PENG block with 30 ml 0.25% ropivacaine +4 mg dexamethasone) or Group Q (USG guided QL block with 30 ml 0.25% ropivacaine +4 mg dexamethasone) 20 min before surgery. MEASUREMENTS: We compared the total perioperative fentanyl consumption between the two groups in the first 24 h as the primary outcome. Other outcomes included time to first rescue analgesia in the postoperative period, NRS scores at rest and on movement at 0, 2, 4, 6, 12, and 24 h, incidence of intraoperative hemodynamic changes, and incidence of postoperative PONV. MAIN RESULTS: There was no significant difference in the total fentanyl consumption between the two groups: 237.5 (150-450) μg in the P group and 250 (125-400) μg in the Q group; p = 0.617. The time to first rescue analgesia was similar in both groups: the P group (198 [123-268] minutes) and the Q group (241 [180-318] minutes); p = 0.120. There was also no difference in pain scores, intraoperative hemodynamic changes, or PONV. CONCLUSION: There was no difference in the perioperative opioid consumption, pain scores, and adverse event rates between the pericapsular nerve group block and anterior quadratus lumborum block in adult patients undergoing unilateral hip arthroplasty. TRIAL REGISTRATION: Clinical Trials Registry of India (CTRI number: CTRI/2023/08/057157).

Humans↗

PubMed2026

Evaluation of the intraoperative analgesic effects of perioperative electroacupuncture: a randomised, blinded clinical trial in dogs.

OBJECTIVE: To evaluate the effect of perioperative electroacupuncture (EA) on intraoperative analgesic requirements in dogs undergoing tibial tuberosity advancement (TTA) surgery. STUDY DESIGN: Prospective, randomised, blinded, controlled clinical study. ANIMALS: A group of 29 client-owned dogs diagnosed with cranial cruciate ligament rupture that underwent TTA surgery. METHODS: Dogs were treated with EA at predefined acupuncture points (LI-4, ST-36, LIV-3, SP-6 and GB-34) perioperatively as additional analgesia (group EA, n = 14) or were allocated to the control group (group C, n = 15). All dogs were anaesthetised with a standardised protocol including methadone, dexmedetomidine, propofol and ketamine. The intraoperative delivery of sevoflurane and fentanyl was guided in response to signs of nociception by a purpose-designed flowchart, by the same anaesthetist who was blinded to treatment group. A Wilcoxon rank sum test was applied for the fentanyl consumption analysis. Heart rate, mean arterial blood pressure and end-tidal sevoflurane were descriptively analysed between groups for specific time points. A p value < 0.05 was considered significant. RESULTS: The EA group needed significantly less fentanyl with 0.7 (0-2.7) μg kg-1 hour-1 administered versus 2.0 (1.2-5.5) μg kg-1 hour-1 in group C (p = 0.031). Fifty percent of the EA group was not administered a fentanyl bolus, whereas all dogs in group C required at least one bolus. CONCLUSIONS AND CLINICAL RELEVANCE: Perioperative EA reduced mean fentanyl consumption by more than 60% in dogs undergoing TTA surgery.

Animals↗

PubMed2026

Application of SPI-guided analgesia in laparoscopic gynecologic surgery: a randomized controlled trial evaluating the remifentanil-sparing effect and predictive value of time-weighted SPI.

This study aimed to achieve two primary objectives: (1) to evaluate the opioid-sparing effect of Surgical Pleth Index (SPI)-directed analgesia during surgery via a randomized controlled trial (RCT), and (2) to propose and preliminarily assess a novel dynamic metric, Threshold-based Time-Weighted SPI (Tb-TW-SPI), which integrates stimulus intensity and duration, for its predictive efficacy regarding postoperative moderate-to-severe pain. Employing an RCT combined with exploratory analysis, 61 patients undergoing elective laparoscopic gynecologic surgery were randomized into an SPI-directed analgesia group or a conventional analgesia group. The primary outcome was total intraoperative remifentanil consumption. Postoperatively, an exploratory analysis of the control group data evaluated the correlation between Tb-TW-SPI and Numeric Rating Scale (NRS) pain scores in the post-anesthesia care unit (PACU), calculating its predictive value for moderate-to-severe pain (NRS ≥ 4). Results: The SPI-directed group required significantly less intraoperative remifentanil than the conventional group [median (IQR): 5.84(5.02,6.62)vs. 6.96(5.81,8.19)µg/kg/h; P = 0.016]. Postoperative pain scores did not differ significantly between groups (P > 0.05). Exploratory analysis of the conventional analgesia group revealed that Tb-TW-SPI values were significantly higher in patients with moderate-to-severe postoperative pain (NRS ≥ 4) compared to those without (P = 0.0417).The area under the ROC curve for Tb-TW-SPI predicting this pain was 0.74 (95% CI: 0.52-0.96), with 67% sensitivity and 76% specificity at an optimal cutoff of 1210. This RCT suggests that SPI-directed analgesia can safely and moderately reduce intraoperative remifentanil consumption. Furthermore, the proposed Tb-TW-SPI metric, in this exploratory analysis, suggests potential for predicting postoperative pain, though this finding requires validation in larger cohorts with higher-frequency SPI sampling, offering a new direction for SPI interpretation. Large-scale, multicenter trials are warranted to validate the predictive utility of Tb-TW-SPI. Clinical Trial Registration, China Clinical Trial Registry: ChiCTR2400088444.

Humans↗

PubMed2026

Evaluating the utility of melatonin in spine surgery: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Spine surgery is increasingly performed worldwide, and acute postoperative stressors such as pain and anxiety remain highly prevalent despite historical management with opioids and other pharmacological agents. Recently, interest has emerged in melatonin administration given its endogenous physiological roles, low cost, favorable adverse event profile, and documented benefits throughout surgical literature. PURPOSE: This study aims to consolidate the existing evidence on melatonin's utility specifically in spine surgery, an area not yet comprehensively evaluated, to inform clinical practice and enhance spine surgeon comprehension. STUDY DESIGN/SETTING: Preregistered on PROSPERO, this systematic review queried PubMed/MEDLINE, CINAHL, SPORTDiscus, and Web of Science on November 21st, 2025, for studies reporting outcomes following melatonin administration in patients undergoing spine surgery. METHODS: Study quality was assessed using the Cochrane Risk-of-Bias 2 tool. Extracted variables included demographics, comparator medications, dosages, and other relevant details. Statistical analyses included frequency-weighted means (FWMs), associated standard deviations, narrative syntheses, and limited meta-analyses, where appropriate. RESULTS: A total of 6 moderate-quality randomized trials were included from 749 screened. Melatonin (3-10 mg) was administered to 227 patients (FWM age=43.3±8.6 years; 46.2% male; BMI=26.6±3.2 kg/m2), placebo to 125 patients (age=43.2±10.1 years; 60% male; BMI=28.5±4.3 kg/m2), and active pharmacologic comparators (fentanyl, gabapentin, dexmedetomidine, zolpidem) to 151 patients (age=46.6±8.9 years; 40.5% male; BMI=26.3±3.5 kg/m2). Procedures primarily involved uncomplicated lumbar laminectomies (1-4 levels), with outcomes assessed up to 24 hours postoperatively. Melatonin was associated with significant improvements in early postoperative VAS-pain scores, blood-pressure-related, analgesic-related, and anxiety-related outcomes versus placebo across most reporting studies. Compared with active pharmacologic agents, significant benefits were observed only in select nausea- and anxiety-related instances. Limited meta-analysis (n=2) demonstrated higher 24-hour VAS-pain for melatonin versus gabapentin, though mean difference was near-negligible and harbored extensive statistical constraints. CONCLUSION: Melatonin demonstrates variable utility following spine surgery, with generally consistent anxiolysis and frequent benefit versus placebo but less consistent and comparatively weaker efficacy relative to active pharmacologic comparators. Future outcome-homogenous studies incorporating more granular, expansive comparator arms and more robust quantitative analyses are needed to further elucidate melatonin's role in advancing spine care. LEVEL OF EVIDENCE: Level II.

Humans↗

PubMed2026

Relationships between cannabis and cocaine use in a randomized trial of combined buprenorphine and naltrexone for DSM-IV cocaine dependence.

BACKGROUND: Cannabis is the most commonly used drug in the United States, and among people who use cannabis, polysubstance use is common and understudied. We aimed to examine the association of tetrahydrocannabinol (THC) positive urine drug screen (+UDS) with the odds of submitting a cocaine + UDS during cocaine use disorder treatment. METHODS: We conducted a secondary data analysis of a previously reported double-blind, placebo-controlled clinical trial, CTN0048. Participants meeting criteria for opioid abuse/dependence were assigned to receive extended-release naltrexone and one of three conditions of buprenorphine (placebo, 4 mg/day, 16 mg/day) for 8 weeks. Generalized estimating equations (GEE) were used to analyze urine samples (Liu et al., 2018) collected over time, examining the association between THC + UDS and cocaine + UDS during treatment. RESULTS: Participants (n = 301) averaged 46 (SD = 8.64) years of age, were majority male (78.41 %), non-Hispanic (89.70 %), and African American (66.45 %). GEE results indicated that patients who submitted THC + UDS had significantly higher odds of submitting cocaine + UDS compared to participants who submitted THC-negative UDS across the 25 time points examined (OR = 1.47, 95 % CI = 1.21-1.79, p = 0.00). Time (OR = 0.9998, 95 % CI: 0.9997, 0.9999, p = 0.018) and the covariate of sex assigned at birth (OR = 1.77, 95 % CI = 1.13-2.77, p = 0.013) were also significant in the model, indicating very small decreases in the odds of submitting a cocaine + UDS over time for all patients and 77 % higher odds of submitting cocaine + UDS for females. CONCLUSION: THC + UDS was associated with increased odds of submitting a cocaine + UDS during treatment. Further investigation is needed to discern whether decreasing THC use will result in reduced cocaine use; however, these results suggest that it may be beneficial to counsel patients on cannabis use cessation both before and during treatment for cocaine use, as it is related to cocaine use treatment outcomes. TRIAL REGISTRATION: Secondary data analysis of ClinicalTrials.gov, TRN: NCT01402492 ("A randomized study to test the safety and effectiveness of buprenorphine in the presence of naltrexone for the treatment of cocaine dependence"; National Drug Abuse Treatment Clinical Trials Network (CTN) clinical trial: CTN0048), Registration date: 27 July 2011.

Humans↗

PubMed2026

Impact on analgesia, diaphragmatic function, and recovery between erector spinae plane block versus superior trunk block in arthroscopic shoulder surgery: a randomized controlled trial.

BACKGROUND: Effective analgesia and preservation of diaphragmatic function are key considerations in analgesia for shoulder surgery. The superior trunk block provides analgesia with reduced phrenic nerve involvement, while the erector spinae plane block offers minimal impact on diaphragm motion. This randomized controlled trial compared the analgesic efficacy, impact on diaphragmatic motion, and postoperative recovery between the two blocks. METHODS: Sixty patients undergoing arthroscopic shoulder surgery were randomized to receive either erector spinae plane block or superior trunk block. Primary outcomes were postoperative VAS and changes in diaphragmatic excursion. Secondary outcomes included Quality of Recovery-15 (QoR-15) scores, morphine-equivalent consumption, and the handgrip strength motor blockade. RESULTS: The superior trunk block resulted in significantly lower dynamic VAS at 1-h postoperatively (0.1 [0.0, 0.2] vs. 5.7 [4.0, 7.6]; p < 0.001) and reduced 24-h morphine consumption (7.8 [2.5, 15.0] mg vs. 12.7 [7.5, 17.3] mg; p = 0.038) compared to the erector spinae plane block. However, diaphragmatic excursion was better preserved in the erector spinae plane block group (8.37% ± 20.7% vs. -20.09% ± 22.2%; p < 0.001), with a lower incidence of partial hemidiaphragm paresis (3.3% vs. 46.7%; p < 0.001). At 24 h postoperatively, QoR-15 scores were higher in the superior trunk block group (p = 0.047), and no patient in either group developed handgrip motor blockade. CONCLUSIONS: Superior trunk block offers superior early postoperative analgesia and better overall recovery, while erector spinae plane block minimizes diaphragmatic impairment. However, the erector spinae plane block may represent an option only in carefully selected patients at high respiratory risk, acknowledging its significantly poorer early analgesic profile.

Humans↗

PubMed2026

Safety Profile of the Non-steroidal Anti-inflammatory Drug Celecoxib in the Short-Term Management of Acute Non-cancer Pain: A Systematic Review with Meta-analysis of Randomised Controlled Trials.

OBJECTIVE: To summarise the literature regarding the safety of short-term use of the non-steroidal anti-inflammatory drug (NSAID) celecoxib. STUDY DESIGN: Systematic review with meta-analysis of randomised trials. Participants comprised individuals of all ages with acute non-cancer pain. Interventions included celecoxib at 200-400 mg/day for up to 10 days. The comparators were placebo, other NSAIDs (including cyclooxygenase-2 [COX-2] inhibitors and non-selective NSAIDS [nsNSAIDS]), or opioids. DATA SOURCES: Five databases were searched from inception to April 2025: Embase, Web of Science, MEDLINE, Cochrane Central Register of Controlled Trials, and Scopus. Additionally, a registry was searched: ClinicalTrials.gov. DATA SYNTHESIS: Meta-analyses using Mantel-Haenszel and random-effects model were used to calculate risk ratios (RRs) and 95% confidence intervals (CIs) for severe cardiovascular, respiratory, and gastrointestinal adverse events and secondary outcomes. The Cochrane Risk of Bias Tool for randomised trials (RoB-2) was used to assess bias risk. The Grading of Recommendation Assessment, Development and Evaluation (GRADE) was conducted to assess the certainty of evidence of each reported outcome. RESULTS: Title/abstract and full text screening comprised 3976 and 273 studies, respectively. Fifty studies were included with 10,693 participants. The RRs for adverse events were no different between celecoxib and placebo for severe events (3 studies) (RR 0.44 [95% CI 0.10-2.03]), cardiovascular (3 studies) (RR 0.84 [95% CI 0.24-2.92]), respiratory (4 studies) (RR 1.23 [95% CI 0.29-5.26]), and gastrointestinal events (33 studies) (RR 0.96 [95% CI 0.64-1.43]). There was no difference between celecoxib and NSAIDS for gastrointestinal adverse events, RR 0.89 (95% CI 0.68-1.17). Celecoxib had a lower risk compared to opioids for gastrointestinal events, RR 0.34 (95% CI 0.14-0.86), and showed a lower risk of nausea compared with placebo, RR 0.75 (95% CI 0.60-0.93), and nsNSAIDS, RR 0.80 (95% CI 0.64-0.99). Most studies had some risk of bias concerns, and the overall certainty of evidence for most outcomes was very low. Celecoxib appears to be safe for acute non-cancer pain when compared to placebo, NSAIDS, and opioids. It had a lower risk compared to opioids for gastrointestinal adverse events in general, nausea and vomiting, as well as a lower risk for nausea adverse events when compared to placebo and nsNSAIDS. REGISTRATION: PROSPERO-CRD42025642152.

Journal Article↗

PubMed2026

Identification of CD55 as a downstream factor of EP4 receptor signaling in colorectal cancer cells.

Prostaglandin E2 (PGE2) signaling through the E-type prostanoid 4 (EP4) receptor has been implicated in the pathophysiology of colorectal cancer (CRC). We herein identified decay-accelerating factor, also known as CD55, as a novel CRC-associated downstream factor of the EP4 receptor. The integration of transcriptomic profiling of PGE2-stimulated HCA-7 human colon cancer cells with analyses of cancer genomic databases predicted CD55 as a potential EP4 receptor-regulated target. Inhibitor-based experiments showed the induction of CD55 after a PGE2 stimulation required the EP4 receptor and Gi protein in HCA-7 cells, whereas protein kinase A signaling was dispensable. In combination with a toxicogenomic database analysis, p38 mitogen-activated protein kinase (MAPK) was identified as the predominant effector connecting the EP4 receptor to CD55 upregulation. A single-cell RNA-seq re-analysis of human CRC tissues revealed CD55 upregulation and p38 MAPK-related gene set enrichment in epithelial cells expressing the EP4 receptor, suggesting that this induction mechanism may operate in a subset of epithelial cells in clinical specimens. Collectively, these results delineate a PGE2/EP4 receptor/Gi protein/p38 MAPK signaling axis that induces CD55 expression in HCA-7 cells and epithelial tumor cells, provide new mechanistic clues for understanding the regulation of complement regulatory molecule CD55 expression by prostaglandin signaling.

Humans↗

PubMed2026

Effects of GLP-1 Receptor Agonists and Dual GIP/GLP-1 Receptor Agonists on Inflammatory and Metabolic Biomarkers in Type 2 Diabetes: A Systematic Review and Meta-Analysis.

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and dual GIP/GLP-1 receptor agonists improve cardiovascular outcomes in type 2 diabetes mellitus (T2DM), but their effects on inflammatory and oxidative biomarkers are not fully defined. MATERIALS AND METHODS: We searched PubMed, Ovid MEDLINE, Scopus, Web of Science and the Cochrane Library from inception to 19 February 2026 for randomised controlled trials (RCTs) in adults with T2DM comparing a GLP-1RA or dual GIP/GLP-1 agonist with placebo or active therapy, and reporting C-reactive protein (CRP or high-sensitivity CRP [hs-CRP]), interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), malondialdehyde (MDA) or adiponectin. Random-effects meta-analyses were conducted using standardised mean differences (SMDs). RESULTS: Forty-one RCTs were included. GLP-1RAs significantly reduced CRP/hs-CRP (27 studies, 1991 participants; SMD -0.37, 95% CI -0.59 to -0.14) and MDA (3 studies, 272 participants; SMD -0.98, 95% CI -1.65 to -0.30), and increased adiponectin (16 studies, 1327 participants; SMD 0.30, 95% CI 0.13 to 0.46). Pooled effects on IL-6 (17 studies, 1068 participants; SMD -0.14, 95% CI -0.37 to 0.10), TNF-α (16 studies, 1164 participants; SMD -0.25, 95% CI -0.61 to 0.12) and MCP-1 (7 studies, 450 participants; SMD -0.27, 95% CI -0.58 to 0.03) were not statistically significant, although MCP-1 decreased in sensitivity analyses. Across biomarkers, heterogeneity was moderate to high. Two tirzepatide RCTs (562 participants) showed a significant reduction in IL-6 (SMD -0.28, 95% CI -0.47 to -0.09) and a non-significant trend towards lower CRP/hs-CRP. CONCLUSIONS: In adults with T2DM, incretin-based therapies consistently lower CRP/hs-CRP, reduce oxidative stress (MDA) and increase adiponectin, while effects on IL-6 and TNF-α are more variable. These data support a selective anti-inflammatory and metabolic regulatory profile of GLP-1-based therapy, but heterogeneity and limited data for some biomarkers warrant cautious interpretation and further mechanistic studies. TRIAL REGISTRATION: PROSPERO number: CRD420261321430.

Humans↗

PubMed2026

Identification of CXCL13 as an agonist and CXCL11 as an inverse agonist for the viral G protein-coupled receptor ORF74.

Kaposi's sarcoma-associated herpesvirus (KSHV) establishes latent infection in humans, but under conditions of immune suppression, it may reactivate and contribute to severe diseases, including Kaposi's sarcoma (KS) and B-cell malignancies. The KSHV genome encodes a single G protein-coupled receptor (GPCR), open reading frame 74 (ORF74), which shows homology to human chemokine receptors. Since its identification in 1996, ORF74 has subsequently been shown to interact with a broad range of human CXC chemokines, as well as CCL1 and the viral chemokine vCCL2. Compared with many human chemokine receptors, ORF74 displays high basal activity. These properties allow ORF74 to deregulate host cellular pathways through constitutive and chemokine-modulated signaling. In this study, we evaluated several human chemokines that, to our knowledge, had not previously been tested in ORF74-dependent cellular assays. Whereas CXCL9, CXCL14, CXCL16 and CXCL17 did not interact with ORF74, CXCL13 was identified as an additional ORF74 agonist and CXCL11 as an inverse agonist. CXCL13 dose-dependently induced ORF74-mediated Ca2+ release, β-arrestin1/2 recruitment and chemotaxis, and enhanced basal nuclear factor κB (NF-κB) activity in ORF74-expressing cells. In contrast, CXCL11 showed no detectable ORF74 agonist activity in the calcium mobilization or chemotaxis assay, but antagonized CXCL1-induced responses in both readouts. CXCL11 also elicited inverse agonist-like responses in β-arrestin1/2 recruitment assays and reduced basal NF-κB signaling. Our study thus reveals CXCL13 and CXCL11 as two additional chemokine ligands for ORF74, further expanding the pharmacological profile of this viral GPCR.

Humans↗

PubMed2026

Genomic identification and functional characterization of the nuclear receptor gene family in relation to sex determination and gonad development in the Pacific oyster (Crassostrea gigas).

Nuclear receptors (NRs) are a large superfamily of transcription factors that control a wide range of physiological processes by modulating the expression of downstream target genes. Numerous studies have confirmed that NR family members play critical and conserved roles in sex determination and gonadal development across metazoans. However, in mollusks, systematic characterization of NRs and their potential functions in gonadal regulation remain largely unexplored. In this study, 46 NR gene family members in the Pacific oyster (Crassostrea gigas) were identified and assigned to eight subfamilies. All NR family members contain at least one of the two core domains (DNA-binding domain, DBD; ligand-binding domain, LBD), and conserved exon-intron structures were observed within the same subgroup, indicating their evolutionary conservation. Furthermore, expression profiling revealed high expression of CgNR2F, CgNR5A1-1, and CgNR0B1 in undifferentiated gonads, suggesting their potential involvement in sex determination. CgNR1A and CgNR2E5 were specifically expressed in female gonads and exhibited female-biased expression patterns, indicating a putative role in ovarian development. Moreover, CgNR3A and CgNR3B showed high expression levels during the undifferentiated stage and early male development stage, implying their possible participation in male gonadal development and gametogenesis. These results expand the understanding of the NR gene family in C. gigas and help elucidate the potential functions of NR genes in sex determination and gonadal development.

Animals↗

PubMed2026

Comparative analyses of olfactory receptor repertoires in Schizothorax fish based on the chromosome-level genomes: Implications for regulatory roles of dietary differentiation and ploidy variation.

The olfactory receptor (OR) genes constitute the molecular basis of fish olfaction, mediating survival behaviors and environmental adaptation while coevolving with habitat-driven evolution. Schizothorax, a cyprinid genus endemic to the Qinghai-Tibetan Plateau, exhibits remarkable dietary divergence and ploidy variation in response to plateau environmental changes, which presumably facilitates the adaptive evolution of OR genes. However, the evolutionary patterns of OR genes associated with trophic divergence and ploidy variation in this genus remain unclear. In this study, three species were selected: the herbivorous diploid S. macropogon, the carnivorous diploid S. lantsangensis, and the herbivorous tetraploid S. curvilabiatus. S. macropogon possessed 142 OR genes (92.25% functional), primarily located on chromosomes 14 and 24, with the fewest sequence clusters. Such compact gene repertoire and highly overlapping chromosomal clusters indicated specialization for a herbivorous olfactory niche. S. lantsangensis contained 127 OR genes (93.70% functional), concentrated on chromosomes 4 and 5, with fewer sequence clusters and a scattered distribution, reflecting evolution of OR genes under carnivorous feeding habits. The herbivorous tetraploid S. curvilabiatus exhibited striking features: 316 OR genes (94.30% functional), the most subfamilies, unique ε and κ OR subfamilies, and species-specific motifs. These characteristics revealed that ploidy, rather than herbivory, dominated OR gene evolution. In conclusion, dietary differentiation and ploidy variation together drove olfactory adaptive evolution in Schizothorax, providing new insights into vertebrate OR gene ecological adaptation.

Animals↗

PubMed2026

Structural and tissue-specific organisation of endocrine Fgf19 and Fgf21 signalling in rainbow trout.

Endocrine fibroblast growth factors (FGF19 subfamily) play a key role in regulating metabolic homeostasis in vertebrates. However, their functional diversification in salmonids remains poorly understood. In this study, we conducted an integrative characterisation of Fgf19 and Fgf21 signalling in rainbow trout (Oncorhynchus mykiss) by combining phylogenetic, structural and expression analyses. Phylogenetic analyses revealed the conservation of single fgf19 and fgf21 genes, despite the extensive expansion of receptors post-Ss4R (salmonid-specific fourth-round whole genome duplication). Structural modelling and molecular dynamics simulations demonstrated the stable interactions of both ligands to multiple Fgfr isoforms, with receptor-specific energetic profiles and conserved core interaction residues. Tissue expression profiling revealed clear differences from mammalian models, such as predominant hepatic fgf19 expression and the absence of hepatic fgf21 under basal conditions. In addition, there were complex and tissue-dependent distributions of fgfr and klotho transcripts. These findings support a receptor-driven diversification model of endocrine Fgf signalling in salmonids, suggesting enhanced endocrine plasticity associated with the retention of receptors following post-genomic duplication. Taken together, our findings provide new insights into the structural and regulatory organisation of endocrine Fgf signalling, as well as its potential role in metabolic regulation in rainbow trout.

Animals↗

PubMed2026

Identification and characterization of G protein-coupled receptors in the nocturnal halictid bee Megalopta genalis.

G protein-coupled receptors (GPCRs) are one of the largest families of membrane proteins in insects, regulating vision, neural signal transduction, and various physiological behaviors. Megalopta genalis exhibits a unique facultatively eusocial lifestyle and possesses adaptations for nocturnal activity; however, its GPCR family has not yet been systematically characterized. In this study, we performed genome-wide identification, phylogenetic analysis, and expression profiling of GPCRs in M. genalis by integrating genomic annotation and transcriptomic analysis. The results showed that a total of 99 GPCRs were identified in the genome of M. genalis, which were classified into four major families. Here, we show that M. genalis has undergone lineage-specific GPCR repertoire remodeling, marked by the expansion of novel orphan receptors and the systematic loss of multiple receptor subtypes, such as the neuropeptide receptors MIP-R and NPFR. Moreover, opsins have formed a diverse array of combinations and non-GPCR odorant receptors have undergone significant expansion via tandem duplication. Together, these features may represent part of the molecular repertoire associated with the adaptation of M. genalis to a nocturnal lifestyle. Furthermore, transcriptomic analysis revealed distinct spatiotemporal expression divergence within each of the Mth/Mthl and Fz GPCR families, suggesting functional specialization across development and adult tissues. This study provides the first systematic identification and initial functional characterization of GPCRs in M. genalis, revealing an evolutionary pattern characterized by the coexistence of contraction and expansion within the GPCR family. These findings lay a foundation for further studies aimed at elucidating the roles of these GPCRs in regulating M. genalis physiology and behavior.

Animals↗

PubMed2026

Insights from changes in NDEV biomarkers of metabolism: effects of PPARγ and GLP1 receptor agonists on brain metabolism.

BACKGROUND: Insulin resistance (IR) is implicated in central nervous system disorders, including depression and Alzheimer's disease (AD). METHODS: We analyzed biological samples from two cohorts of clinical trial participants: (1) participants with unremitted depression after six months of treatment as usual who received pioglitazone (PPARγ agonist, N = 12) or placebo and (2) middle-aged participants at genetic risk for AD who received liraglutide (glucagon-like peptide 1 [GLP1] receptor agonist, N = 15) or placebo. These cohorts, which previously showed treatment-related improvements in peripheral IR, were used to assess the effects of pioglitazone and liraglutide on CNS insulin signaling using neuron-derived extracellular vesicles (NDEVs) as biomarkers. We utilized biological samples to measure biomarkers of IR in NDEVs. Eleven Akt-mTOR pathway proteins were measured before and after 12 weeks of treatment in both groups. RESULTS: Participants who received pioglitazone experienced broader changes, with significant increases in GSK3β (Ser9), mTOR (Ser2448), and RPS6 (Ser235/Ser236; all P ≤ .02) compared with placebo, and 77% of participants showed mTOR (Ser2448) response. Participants who received liraglutide demonstrated significantly increased NDEV-associated phosphorylated Akt (Ser473) and mTOR (Ser2448; P = .04 and P = .025, respectively) compared with placebo, with 40% and 30% of participants in the liraglutide group showing biomarker response in both Akt (Ser473) and mTOR (Ser2448), respectively. These effects appeared relatively independent from changes in fasting plasma insulin and glucose concentration at 120-minutes during the oral glucose tolerance test. DISCUSSION: Our findings demonstrate CNS-specific biomarker responses to both PPARγ agonists and GLP1 receptor agonists.

Humans↗

PubMed2026

Naltrexone Is Superior to Placebo for Abstinence and Craving Reduction in Alcohol-Associated Cirrhosis: NAL-CI Trial.

BACKGROUND AND AIMS: Alcohol use disorder (AUD) coexisting with cirrhosis carries high morbidity and mortality, with no approved pharmacotherapy for AUD. We evaluated the safety and efficacy of naltrexone, an opioid receptor antagonist, in patients with compensated alcohol-associated cirrhosis (AaC) and AUD. METHODS: One hundred patients with compensated AaC and DSM-5 AUD were randomised 1:1 to naltrexone (50 mg/day) or placebo for 12 weeks. The primary endpoint was point-prevalence abstinence at 12 weeks, defined as no alcohol use in the four preceding weeks. Secondary endpoints included craving (Obsessive Compulsive Drinking Scale [OCDS]-Obsessive and Compulsive subscales), lapses, relapses, and hepatic safety. Standardised psychosocial support was provided to both arms. RESULTS: Baseline characteristics were well matched between groups (mean MELD 12.6 vs. 12.7; CTP score 5.9 vs. 6.2; age 42.9 vs. 44.3 years). AUDIT and OCDS scores were comparable between groups. Abstinence at 12 weeks was significantly higher with naltrexone: 64% (32/50) versus 22% (11/50), p < 0.001; OR 10.86 (95% CI: 1.89-62.2). Naltrexone significantly reduced lapses at 3 months (28% vs. 54%, p = 0.008) and showed a trend toward fewer heavy-drinking relapses (12% vs. 28%, p = 0.07). Maintenance of abstinence at 6 months favoured naltrexone (22% vs. 8%, p = 0.09). No patient developed hepatic decompensation attributable to study medication, and no AST/ALT elevation exceeding 5× ULN was observed in either group. Mean craving scores were lower with naltrexone by week 12 than with placebo: OCDS-O score (6.63 ± 1.16 vs. 9.29 ± 1.78, p < 0.01) and OCDS-C score (6.35 ± 1.23 vs. 9.02 ± 1.86, p < 0.01). Adverse events were comparable between the groups. CONCLUSION: Naltrexone is safe and effective in patients with compensated alcohol-associated cirrhosis, achieving a threefold higher abstinence rate and significantly reducing craving compared with placebo. These findings support the use of naltrexone as a pharmacological option in patients with compensated AaC and AUD. TRIAL REGISTRATION: NCT04391764.

Humans↗

PubMed2026

Meta-analysis of source identification and apportionment in soil: A systematic review of analytical procedures, receptor modeling, and environmental applications.

Soil pollution poses significant risks to ecosystems and human health, necessitating accurate source identification and apportionment to guide mitigation strategies. This systematic review evaluates the application of Positive Matrix Factorization (PMF) and other receptor models in soil pollution studies, focusing on analytical procedures, tracer indicators, and environmental applications. This review aims to provide a comprehensive framework for conducting soil source apportionment studies, aiding policymakers in designing effective, region-specific environmental management strategies by compiling global trends and methodological insights. The study addresses sampling protocols, emphasizing representativeness and quality control. Data from 500 peer-reviewed publications highlight the dominance of research in China, Eastern Europe, and South Asia, with agricultural soils being the most frequently studied. Key findings reveal that traffic emissions (20.8 %) and industrial activities (19.4 %) are the primary global contributors to soil contamination, with regional variations such as coal combustion in cold climates and agricultural inputs in developing regions. Policy recommendations include stricter industrial regulations, sustainable agricultural practices, and targeted remediation efforts based on source-specific risks.

Soil Pollutants↗