Preoperative anxiety-induced glucocorticoid signaling reduces GABAergic markers in spinal cord and promotes postoperative hyperalgesia by affecting neuronal PAS domain protein 4

Blocking brown adipocyte β3-adrenoceptor attenuates blood-spinal cord barrier impairment and chronic postsurgical pain in a rat model of preoperative stress

Preoperative stress has been recognized as an independent risk factor for chronic postsurgical pain (CPSP). However, the underlying mechanisms of CPSP influenced by preoperative stress remain elusive. Previous studies indicated that excessive stress could induce disruption of the blood-spinal cord barrier (BSCB). We wondered whether and how BSCB involves in CPSP by using a single prolonged stress (SPS) combining plantar incision model in male rats to mimic preoperative stress-related postsurgical pain. Here, we observed that preoperative SPS-exposed rats exhibited relentless incisional pain, which was accompanied by impairment of BSCB and persistent elevation of serum IL-6. Intraperitoneal injections of Tocilizumab (an IL-6 receptor monoclonal antibody) not only mitigated BSCB breakdown but also alleviated pain behaviors. In addition, intervening β3-adrenoceptor (ADRB3) signaling in brown adipocytes by SR59230a (a specific ADRB3 antagonist) treatment or removal of brown adipose tissues could effectively decrease serum IL-6 levels, ameliorate BSCB disruption, and alleviate incisional pain. Further results displayed that SI-exposed rats also showed markedly spinal microglia activation. And exogenous His-tagged IL-6 could pass through the disrupted BSCB, which might contribute to microglia activation. Injection of SR59230a or ablation of brown adipose tissues could effectively reduce the activation of spinal microglia. Thus, our findings suggest that serum IL-6 induced by brown adipocyte ADRB3 signaling contributed to BSCB disruption and spinal microglia activation, which might be involved in preoperative stress mediated CPSP. This work indicates a promising treatment strategy for preoperative stress induced CPSP by blocking ADRB3.

Effects of Perioperative Music Therapy on Patients with Postoperative Pain and Anxiety: A Systematic Review and Meta-Analysis

Background: As a mind-body therapy, music may have a positive effect on patients with postoperative pain and anxiety. Objective: The aim of this systematic review and meta-analysis was to explore the effects of perioperative music therapy on postoperative pain and anxiety based on existing clinical trials. Methods: The Cochrane Library, PubMed, and Embase were searched from their inception to August 2022, selected the literature according to the inclusion and exclusion criteria, and completed the meta-analysis using RevMan 5.3. Results: A total of 19 eligible randomized controlled trials were enrolled, including 1803 patients. The results of the meta-analysis showed that the scores of pain (standardized mean difference [SMD], -0.90; 95% confidence interval [CI], -1.26 to -0.53; p < 0.00001) and anxiety (SMD, -0.75; 95% CI, -1.19 to -0.31; p = 0.0008) decreased in the music group on postoperative day 1. The blood pressure (mean difference [MD], -5.29; 95% CI, -9.53 to -1.06; p = 0.01) and heart rate (MD, -6.13; 95% CI, -11.69 to -0.58; p = 0.03) also decreased on the same day. Further, the score of change in pain (SMD, 0.35; 95% CI, 0.01 to 0.68; p = 0.04) and anxiety (SMD, 1.35; 95% CI, 0.01 to 2.69; p = 0.05) increased between preoperative and postoperative days in the music group. However, the scores of hospital satisfaction (MD, -0.07; 95% CI, -1.40 to 1.27; p = 0.92) and incidences of postoperative nausea and vomiting (risk ratio, 0.41; 95% CI, 0.13 to 1.34; p = 0.14) did not decrease in the music group. Conclusion: Perioperative music therapy can significantly reduce postoperative pain and anxiety and avoid fluctuations in blood pressure and heart rate but does not improve patient hospital satisfaction or incidences of postoperative nausea and vomiting.

Prevalence and factors associated with surgery anxiety in hospitalized patients: a point-prevalence study

BACKGROUND

Preoperative anxiety is a challenging problem in the preoperative care of patients. Identifying risk factors helps nurses provide psychological support during the pre-operative visit so that stress can be reduced.

AIMS

This study aimed to determine the prevalence of surgical anxiety and related factors in hospitalized surgical patients.

METHODS

This research was designed as a point-prevalence study. The study was completed with 223 patients hospitalized in the surgical clinics of a tertiary hospital in Turkey. Surgical anxiety questionnaire (SAQ) and State-trait anxiety inventory (STAI) were used for the assessment of anxiety.

RESULTS

Preoperative anxiety prevalence was 69.5% according to the SAQ and 49.3% according to STAI. Women, participants with no primary school education, those who were unemployed and had low income, those with no previous surgery, those living in fear of surgery, the participants who underwent major surgery and general anesthesia, and those who did not have knowledge about the surgical procedure and anesthesia had higher anxiety according to the two scales. A highly significant and positive correlation was found between total STAI and total SAQ.

CONCLUSION

The importance of surgical anxiety for the health system, which affects two out of every three hospitalized patients, should not be underestimated. Therefore, national and global plans should be made to prevent and manage surgical anxiety.

Preoperative Anxiety in Patients with Pancreatic Cancer: What Contributes to Anxiety Levels in Patients Waiting for Surgical Intervention

Pancreatic cancer is one of the most lethal malignancies. Currently, the only treatment is surgical resection, which contributes to significant preoperative anxiety, reducing quality of life and worsening surgical outcomes. To date, no standard preventive or therapeutic methods have been established for preoperative anxiety in pancreatic patients. This observational study aims to identify which patients' socio-demographic, clinical and psychological characteristics contribute more to preoperative anxiety and to identify which are their preoperative concerns. Preoperative anxiety was assessed the day before surgery in 104 selected cancer patients undergoing similar pancreatic major surgery, by administering the STAI-S (State-Trait Anxiety Inventory Form) and the APAIS (Amsterdam Preoperative Anxiety and Information Scale). Our data suggest that patients with high STAI-S showed higher levels of APAIS and that major concerns were related to surgical aspects. Among psychological characteristics, depressive symptoms and trait anxiety appeared as risk factors for the development of preoperative anxiety. Findings support the utility of planning a specific psychological screening to identify patients who need more help, with the aim of offering support and preventing the development of state anxiety and surgery worries in the preoperative phase. This highlights also the importance of good communication by the surgeon on specific aspects related to the operation.

Stress-induced changes in nociceptive responding post-surgery in preclinical rodent models

Chronic post-surgical pain affects up to 85% of individuals depending on the type of surgery, the extent of inflammation, tissue and/or nerve damage. Pre-surgical stress is associated with greater pain intensity, prolonged recovery and is one of the main risk factors for the development of chronic post-surgical pain. Clinically valid animal models provide an important means of examining the mechanisms underlying the effects of stress on post-surgical pain and identifying potential novel therapeutic targets. This review discusses the current data from preclinical animal studies examining the effect of stress on post-surgical pain, the potential underlying mechanisms and gaps in the knowledge that require further investigation.

Duration of Reduction in Enduring Stress-Induced Hyperalgesia Via FKBP51 Inhibition Depends on Timing of Administration Relative to Traumatic Stress Exposure

Chronic pain development is a frequent outcome of severe stressor exposure, with or without tissue injury. Enduring stress-induced hyperalgesia (ESIH) is believed to play a central role, but the precise mechanisms mediating the development of chronic post-traumatic pain, and the time-dependency of these mechanisms, remain poorly understood. Clinical and preclinical data suggest that the inhibition of FK506-binding protein 51 (FKBP51), a key stress system regulator, might prevent ESIH. We evaluated whether peritraumatic inhibition of FKBP51 in an animal model of traumatic stress exposure, the single prolonged stress (SPS) model, reversed ESIH evaluated via daily mechanical von Frey testing. FKBP51 inhibition was achieved using SAFit2, a potent and specific small molecule inhibitor of FKBP51, administered to male and female Sprague-Dawley rats via intraperitoneal injection. To assess timing effects, FKBP51 was administered at different times relative to stress (SPS) exposure. SAFit2 administration immediately after SPS produced a complete reversal in ESIH lasting >7 days. In contrast, SAFit2 administration 72 hours following SPS produced only temporary hyperalgesia reversal, and administration 120h following SPS had no effect. Similarly, animals undergoing SPS together with tissue injury (plantar incision) receiving SAFit2 immediately post-surgery developed acute hyperalgesia but recovered by 4 days and did not develop ESIH. These data suggest that: 1) FKBP51 plays an important, time-dependent role in ESIH pathogenesis, 2) time windows of opportunity may exist to prevent ESIH via FKBP51 inhibition after traumatic stress, with or without tissue injury, and 3) the use of inhibitors of specific pathways may provide new insights into chronic post-traumatic pain development. PERSPECTIVE: The current work adds to a growing body of literature indicating that FKBP51 inhibition is a highly promising potential treatment strategy for reducing hyperalgesia. In the case of post-traumatic chronic pain, we show that such a treatment strategy would be particularly impactful if administered early after traumatic stress exposure.

Genetic and epigenetic mechanisms influencing acute to chronic postsurgical pain transitions in pediatrics: Preclinical to clinical evidence

Background

Chronic postsurgical pain (CPSP) in children remains an important problem with no effective preventive or therapeutic strategies. Recently, genomic underpinnings explaining additional interindividual risk beyond psychological factors have been proposed.

Aims

We present a comprehensive review of current preclinical and clinical evidence for genetic and epigenetic mechanisms relevant to pediatric CPSP.

Methods

Narrative review.

Results

Animal models are relevant to translational research for unraveling genomic mechanisms. For example, Cacng2, p2rx7, and bdnf mutant mice show altered mechanical hypersensitivity to injury, and variants of the same genes have been associated with CPSP susceptibility in humans; similarly, differential DNA methylation (H1SP) and miRNAs (miR-96/7a) have shown translational implications. Animal studies also suggest that crosstalk between neurons and immune cells may be involved in nociceptive priming observed in neonates. In children, differential DNA methylation in regulatory genomic regions enriching GABAergic, dopaminergic, and immune pathways, as well as polygenic risk scores for enhanced prediction of CPSP, have been described. Genome-wide studies in pediatric CPSP are scarce, but pathways identified by adult gene association studies point to potential common mechanisms.

Conclusions

Bench-to-bedside genomics research in pediatric CPSP is currently limited. Reverse translational approaches, use of other -omics, and inclusion of pediatric/CPSP endophenotypes in large-scale biobanks may be potential solutions. Time of developmental vulnerability and longitudinal genomic changes after surgery warrant further investigation. Emergence of promising precision pain management strategies based on gene editing and epigenetic programing emphasize need for further research in pediatric CPSP-related genomics.

Spinal microglial activation promotes perioperative social defeat stress-induced prolonged postoperative pain in a sex-dependent manner

Prolonged postsurgical pain, which is associated with multiple risk factors in the perioperative stage, is a common medical and social problem worldwide. Suitable animal models should be established to elucidate the mechanisms underlying the perioperative prolonged postsurgical pain. In this study, standard and modified social defeat stress mice models, including chronic social defeat stress (CSDS), chronic nondiscriminatory social defeat stress (CNSDS) and vicarious social defeat stress (VSDS), were applied to explore the effect of perioperative social defeat stress on postsurgical pain in male and female mice. Our results showed that exposure to preoperative CSDS could induce prolonged postsurgical pain in defeated mice regardless of susceptibility or resilience differentiated by the social interaction test. Similar prolongation of incision-induced mechanical hypersensitivity was also observed in both sexes upon exposing to CNSDS or VSDS in the preoperative period. Moreover, we found that using the modified CNSDS or VSDS models at different recovery stages after surgery could still promote abnormal pain without sex differences. Further studies revealed the key role of spinal microglial activation in the stress-induced transition from acute to prolonged postoperative pain in male but not female mice. Together, these data indicate that perioperative social defeat stress is a vital risk factor for developing prolonged postoperative pain in both sexes, but the promotion of stress-induced prolonged postoperative pain by spinal microglial activation is sexually dimorphic in mice.

Preoperative Anxiety Levels in Surgical Patients: A Comparison of Three Different Scale Scores

PURPOSE

The aim of this study was to compare Anxiety Specific to Surgery Questionnaire (ASSQ) with Spielberger State-Trait Anxiety Inventory (STAI) and Amsterdam Preoperative Anxiety and Information Scale (APAIS) in the assessment of preoperative anxiety level and to evaluate the fears associated with surgery and anesthesia in surgical patients.

DESIGN

This is descriptive, correlational, and cross-sectional study.

METHOD

The study sample included 507 surgical patients in four surgery wards who underwent elective surgery. All the data were collected using The Descriptive Characteristics and Clinical Information Form, STAI, APAIS and ASSQ.

FINDINGS

A majority (70.8%) of the participants had fears associated with surgery and anesthesia and nearly half of them had a moderate level of preoperative anxiety. Anxiety prevalence was 46.4% according to the APAIS, 44.4% according to STAI and 49.3% according to ASSQ. Women, participants with no primary school education, participants undergoing major surgery and general anesthesia who did not have knowledge about the surgical procedure, and surgical complications had higher anxiety according to three scale scores.

CONCLUSION

Nearly half of the participants had moderate/high preoperative anxiety, there were consistent results among the scales and the tools were interchangeable to evaluate the preoperative anxiety level in the surgical patients.

Essential Functions of the Transcription Factor Npas4 in Neural Circuit Development, Plasticity, and Diseases

Signaling from the synapse to nucleus is mediated by the integration and propagation of both membrane potential changes (postsynaptic potentials) and intracellular second messenger cascades. The electrical propagation of postsynaptic potentials allows for rapid neural information processing, while propagating second messenger pathways link synaptic activity to the transcription of genes required for neuronal survival and adaptive changes (plasticity) underlying circuit formation and learning. The propagation of activity-induced calcium signals to the cell nucleus is a major synapse-to-nucleus communication pathway. Neuronal PAS domain protein 4 (Npas4) is a recently discovered calcium-dependent transcription factor that regulates the activation of genes involved in the homeostatic regulation of excitatory–inhibitory balance, which is critical for neural circuit formation, function, and ongoing plasticity, as well as for defense against diseases such as epilepsy. Here, we summarize recent findings on the neuroprotective functions of Npas4 and the potential of Npas4 as a therapeutic target for the treatment of acute and chronic diseases of the central nervous system.