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Hestehave, S.

Publications and source records attributed to Hestehave, S..

13 recordsLinked to original sources

Vertical climbing in mice: a translationally relevant measure of pain-related impact on natural behaviour

Despite urgent need for better analgesics, drug development has been complicated by incomplete bench-to-bedside translation. A likely contributing factor is the poor connection between the experimenter-evoked pain-related measures often used in preclinical models, and the clinical symptoms, like broader functional impairment, reported by patients. Here, we asked whether vertical climbing, a species-specific elective behaviour in mice, could serve as a measure of pain-related impairment. We tested male and female mice in a wide range of pain-related models including models of post-operative pain, inflammatory injury, osteoarthritis, rheumatoid arthritis, cancer-induced bone pain, fibrous dysplasia, neuropathic pain, migraine-related pain and facial neuropathy. Vertical climbing was reduced in all models, across five different laboratories, demonstrating the robustness and consistency of this type of behaviour as a novel pain-related outcome measure. Reduced climbing correlated significantly with established pain-related measures, but its time course diverged from that of evoked mechanical allodynia, while aligned more closely with other non-evoked behaviours, like burrowing, home cage activity, wheel running or weight bearing. Pharmacological validation was bidirectional: gabapentin restored climbing in mice with neuropathic injury, and naltrexone reinstated the climbing deficit in mice that had recovered from intraplantar CFA, consistent with persistent pain held in remission by endogenous opioid signalling. Overall, our results indicate that voluntary vertical climbing is a stable, elective behaviour that provides a robust and translationally relevant measure of pain-related functional impairment in mice.

neuroscience↗

Evaluating home-cage-activity metrics for detecting postprocedural pain in a plantar incision mouse model

Detection of postoperative pain in mice is challenging, and there is a need for unbiased, automated methods. Home-cage monitoring systems are promising, but their ability to detect mild pain remains unclear. We evaluated whether home-cage activity measures can be used to detect pain-related changes in a plantar incision model of postoperative pain. First, we confirmed the presence of local hypersensitivity using von Frey filaments on 48 C57BL/6JRj mice (24 males, 24 females). Subsequently, we pair-housed 64 mice (32 males, 32 females) and allocated them to receive either a 4 mm plantar incision on the hind paw under anaesthesia, or anaesthesia alone. Baseline locomotion and voluntary wheel-running activity were recorded over five days, followed by four days of postprocedural monitoring in the home cages. Both procedure groups (incision and anaesthesia-only) showed reduced locomotion and running wheel activity relative to baseline. However, activity measures did not differ between incised and anaesthesia-only mice, and we detected no sex-related effects. Under these conditions, home cage activity measures did not reliably discriminate pain-related behavioural changes in the model, despite the model showing local mechanical hypersensitivity in the von Frey test. Together, these findings indicate that, given the mild and localised nature of the plantar incision mouse model, commonly used home-cage metrics cannot yet reliably detect subtle pain-related behavioural changes.

animal behavior and cognition↗

Neonatal surgical injury alters social behaviour and cortical network responses to adult incision

Early-life painful events can influence brain development and behaviour later in life, yet the neural mechanisms underlying these long-term effects remain poorly understood. In particular, exposure to pain or tissue injury during early postnatal life has been associated with altered sensory processing, emotional regulation and behavioural responses later in life. Here we investigated whether early-life surgical pain alters adult behavioural and cortical network responses to injury. Using a rat model of neonatal hindpaw incision followed by repeat adult surgical incision, we combined behavioural analysis with continuous electrophysiological recordings from the medial prefrontal cortex (mPFC) and primary somatosensory cortex (S1) in freely moving animals. Early-life incision did not produce an overt alteration in adult social behaviour under baseline conditions. However, following adult injury, rats with prior neonatal incision showed altered social behavioural responses compared with animals receiving an incision only in adulthood. At the network level, adult incision increased beta-gamma phase-amplitude coupling within the mPFC and S1-mPFC theta coherence in animals experiencing their first injury, but not in those incised neonatally. Our evidence indicates that the relationship between mPFC coupling and social interaction differed according to neonatal injury history, revealing a lasting reorganisation of cortical network recruitment and brain-behaviour coupling after repeat injury.

neuroscience↗

Voluntary wheel running provides pain relief but transiently exacerbates gait impairments in male and female mice with unilateral osteoarthritis

ObjectivePhysical activity is a first-line therapeutic intervention for managing osteoarthritis-related pain and functional impairment. However, the growing literature questions the long-term relevance of exercise-induced improvements in patients, while pre-clinical research evidence base is limited by reliance on stressful, forced exercise paradigms which do not reflect voluntary engagement. Here, we aimed to investigate the effects of voluntary wheel running on the pain experience in mice with joint pain. DesignWe investigated the impact of free access to a running wheel on sensory, functional and affective outcomes following unilateral intra-articular injection of monoiodoacetate in single-housed male and female C57Bl/6J mice. ResultsMonoiodoacetate injection transiently reduced running activity in both sexes; however, females rapidly resumed and sustained high activity levels over a two-month period, while males showed a progressive decline in running distance. Active males and females showed improvements in the monoiodoacetate-induced hindpaw secondary mechanical hypersensitivity. Moreover, mechanical thresholds positively correlated with the distance ran after injury, suggesting a functional relationship between exercise and secondary pain relief. However, access to a wheel temporarily exacerbated several monoiodoacetate-induced gait impairments in both sexes. Finally, while there were no obvious effects of running on anxio-depressive-like behaviours or cognitive functioning, exercise significantly impacted stress-induced faecal output and phenotypic regulation of body weight. ConclusionsOur findings suggest that persistent loading of an injured knee joint may compromise functional outcomes independently of pain relief away from the joint, underscoring a critical consideration for exercise-based therapeutic strategies in osteoarthritis.

animal behavior and cognition↗

Pre-injury subchronic stress confers sex-specific protection against pain-associated symptoms in osteoarthritic mice

Exposure to stress in adulthood alters the manifestation of persistent pain, yet its role in chronic pain vulnerability remains unclear. Here, we report that sub-chronic restraint stress experienced two weeks before unilateral osteoarthritis (OA) induction via intra-articular mono-iodoacetate (MIA) promoted the emergence of a resilient-like phenotype in adult male mice. This was evidenced by decreased MIA-induced mechanical hypersensitivity, improved gait dynamics and lower anxiety-like behaviour. In contrast, stress exposed females exhibited augmented pain-associated symptoms. In males, sub-chronic stress mitigated several MIA-induced molecular changes, including reduced adult hippocampal neurogenesis, increased glucocorticoid receptor levels in the hypothalamic paraventricular nucleus (PVN) and elevated c-Fos expression in deep spinal laminae, periaqueductal gray (PAG) and PVN. RNA sequencing suggested that restraint stress in males primed the spinal cord for an exacerbated GABAergic response post-MIA and pre-empted some pro-nociceptive MIA-induced transcriptional changes. However, the combination of stress and injury disrupted longevity-associated programs and shifted neurons toward a stress-vulnerable state. These findings reveal that prior stress exposure can modulate the long-term pain experience in osteoarthritis, with sexually dimorphic outcomes. Importantly, these results challenge the notion of stress as inherently maladaptive and underscore its potential to foster resilience to chronic pain.

neuroscience↗

Transient silencing of spinal nociceptive neurons leads to a long-term reduction in joint pain mediated by recruitment of opioid activity.

Chronic inflammatory joint pain remains inadequately treated despite current therapies, creating urgent clinical need for non-addictive alternatives in an era of heightened opioid-related concerns. A promising new approach involves conjugates of botulinum toxin and substance P (SP-BOT), which, when infused locally or spinally, have been shown to produce temporary pain relief in neuropathic mouse models, with its effects declining after approximately 100 days as the construct loses activity. However, its long-term efficacy in inflammatory pain models was unknown. Unexpectedly, in a mouse model of ankle inflammatory arthritis, a single intrathecal injection of SP-BOT at the peak of pain sensitivity produced a persistent reduction in mechanical hyperalgesia that lasted for weeks beyond the loss of construct activity. Furthermore, this late-phase pain relief exhibited a striking mechanism in that a single injection of the opioid antagonist naltrexone partially reversed the anti-hyperalgesia generated by SP-BOT. These data indicate that SP-BOT-mediated neuronal silencing initiates two distinct phases of pain relief. An initial, direct phase is followed by a second, sustained phase that maintains pain alleviation and is driven by endogenous opioid mechanisms.

pharmacology and toxicology↗

Refining the adjuvant-induced rat model of monoarthritis by optimizing the induction volume and injection site

Arthritis is a highly prevalent and disabling condition characterized by pathological joint-damage, clinical symptoms of pain and loss of normal joint function. Monoarthritis can be modelled in rodents via intraarticular injection of complete Freund's Adjuvant (CFA), inducing both joint inflammation and pain-like behaviours. This study aimed to compare the outcome of different injection-volumes and joint-locations, to refine the model's use and to improve its validity. Male and female rats were injected with CFA into the ankle (10, 20 or 50 {micro}l) or knee (10, 50 or 100 {micro}l), and assessed on dynamic weight bearing, locomotor activity, depressive- and anxiety-like behaviours, histology, and a variety of welfare and model-specific parameters. Induction of monoarthritis resulted in relatively similar behavioural profiles regardless of the injected joint. The animals were highly affected in the acute phase, while less in the chronic phase. Greater volumes of CFA were associated with more profound behavioural changes and joint swelling. The largest volumes induced a pronounced local spread of inflammation to adjacent joints, which was reduced with intermediate volumes without attenuating the model validity. Reducing induction volumes to 20 and 50 {micro}l CFA for ankle and knee injections, respectively, appears to be valuable refinement of these models.

neuroscience↗

Stress, Epigenetic Remodeling and FKBP51: Pathways to Chronic Pain Vulnerability

Stress is thought to contribute to the persistence of pain and comorbid anxiety, yet the underlying mechanisms remain unclear. In our pre-clinical model, sub-chronic stress exacerbated subsequently induced inflammatory pain and accelerated the development of comorbid anxiety. DNA methylation analysis of spinal cord tissue after stress exposure revealed hypomethylation in the Fkbp5 promoter site for the canonical FKBP51 transcript and other stress-related genes. However, most epigenetic changes in key regulatory regions did not correlate with changes in gene expression assessed by RNA sequencing, suggesting that stress exposure had remodeled the epigenome without altering gene activity and primed genes for hyper-responsiveness to future challenges. FKBP51 inhibition during stress exposure reduced the exacerbation of inflammatory pain by stress and reversed several stress-induced DNA methylation changes in promoter regions of genes associated with stress and nociception, including Rtn4, Cdk5 and Nrxn1, but not Fkbp5. These results indicate that sub-chronic stress leads to the hypomethylation of Fkbp5 and increased susceptibility to chronic pain driven by FKBP51, but reversing Fkbp5 hypomethylation is not necessary to prevent chronic pain vulnerability, which is likely driven by complex epigenetic regulation of multiple stress-regulated genes.

neuroscience↗

Acute and early stress axis modulation in joint disease permanently reduces pain and emotional comorbidities

Chronic pain affects 20-30% of the population and imposes a significant socio-economic burden as it is often accompanied by substantial emotional comorbidities such as anxiety and depression. Yet, the mechanisms underlying the interactions between the sensory and emotional aspects of chronic pain remain poorly understood. Here, we investigated the role of FKBP51, a regulator of the stress response, in mediating both sensory and emotional symptoms of chronic pain. Inhibition of FKBP51, via genetic deletion or pharmacological blockade, in persistent joint pain reduced fast-onset sensory, functional and activity-related symptoms, as well as late anxio-depressive comorbidities. FKBP51 inhibition after the establishment of the hypersensitive state provided only temporary symptoms relief, while acute inhibition at disease onset protected from the full development of sensory and anxio-depressive symptoms for up to 6 months. Our results also indicated that early pain symptoms could predict the late sensory and emotional outcomes of chronic pain. RNA sequencing of spinal cord tissue revealed that late FKBP51 inhibition transiently altered nociceptive genes associated with mechanical hypersensitivity. In contrast, early inhibition persistently downregulated the Naaa gene, a key regulator of the transition to chronic pain, and reorganized spinal cilia. Our results indicate that early FKBP51 inhibition after injury can persistently reduce chronic pain and prevent the onset of associated emotional comorbidities by modulating critical spinal neurobiological pathways that play pivotal roles in the transition to chronic pain. Significance statementOur study reveals that early inhibition of FKBP51, a modulator in the stress axis, at the onset of joint damage provides sustained pain relief and significantly delays or prevents emotional comorbidities in a sex-dependent manner. In contrast, FKBP51 inhibition initiated after chronic pain is established results in only temporary symptoms improvement. These findings highlight a critical therapeutic window during which timely intervention can prevent the transition from acute to chronic pain. By establishing a predictive link between early therapeutic response and long-term outcomes, this work has important clinical implications for proactive and personalized chronic pain management.

neuroscience↗

Uncoupling the CRMP2-CaV2.2 interaction reduces pain-like behavior in a preclinical osteoarthritis model

Osteoarthritis (OA) represents a significant pain challenge globally, as current treatments are limited and come with substantial and adverse side effects. Voltage-gated calcium channels have proved to be pharmacologically effective targets, with multiple FDA-approved CaV2.2 modulators available for the treatment of pain. Although effective, drugs targeting CaV2.2 are complicated by the same obstacles facing other pain therapeutics-invasive routes of administration, narrow therapeutic windows, side effects, and addiction potential. We have identified a key regulator of CaV2.2 channels, collapsing response mediator protein 2 (CRMP2), that allows us to indirectly regulate CaV2.2 expression and function. We developed a peptidomimetic modulator of CRMP2, CBD3063, that effectively reverses neuropathic and inflammatory pain without negative side effects by reducing membrane expression of CaV2.2. Using a rodent model of OA, we demonstrate the intraperitoneal administration of CBD3063 alleviates both evoked and non-evoked behavioral hallmarks of OA pain. Further, we reveal that CBD3063 reduces OA-induced increased neural activity in the parabrachial nucleus, a key supraspinal site modulating the pain experience. Together, these studies suggest CBD3063 is an effective analgesic for OA pain.

neuroscience↗

Predicting hypersensitivity and comorbid depressive-like behavior in late stages of joint disease using early weight bearing deficit

Chronic pain is a hallmark of joint diseases and is often accompanied by negative affective symptoms such as low mood, anxiety and memory dysfunction. Whether these may be the results of the more obvious sensory and functional symptoms of joint pain is poorly understood and this likely contributes to the difficulty in adequately managing this condition. Here, we have used two mouse models to address this lack of knowledge. Using a model of ankle inflammation and a model of knee osteoarthritis, we found that these models of joint pain induced weight bearing deficits of different magnitude but relatively similar mechanical allodynia that lasted at least 3 months. However, the models were accompanied by very different affective outcomes, as only the model of knee osteoarthritis, that led to significant early changes in activity and sleep patterns, was accompanied by an increase in negative affective behaviors, including cognitive impairments and depressive-like behavior. The models also had different molecular profiles at both spinal and hippocampal levels. Importantly, the functional outcomes measured in the early stages of the disease stage strongly correlated with sensory and emotional profiles at 3 months, suggesting that early functional measures may be used as predictors of the long-term symptoms associated with persistent joint pain. In conclusion, the predictive value of early measures of functional impact of joint disease could prove useful in the clinics for adapted therapeutic approaches for the prevention of emotional comorbidities and better pain management for patients with joint pain.

neuroscience↗

Reliability of sucrose preference testing following short or no food and water deprivation. A Systematic Review and Meta-analysis of rat models of chronic unpredictable stress

The sucrose preference test is a popular test for anhedonia in the chronic unpredictable stress model of depression. Yet, the test does not always produce consistent results. Long food and water deprivation before the test, while often implemented, confounds the results by introducing unwanted drives in the form of hunger and thirst. We assessed the reliability of the test when only short or no fasting was used. We searched PubMed, Embase, and Web of Science for studies in rats exposed to chronic unpredictable stress that used no more than six hours of food and/or water deprivation before the test. Sweet consumptions, for stressed and control/antidepressant-treated animals, in 132 studies were pooled using random effects models. We found a decrease in sweet consumption in stressed rats, compared to controls, that was halved when a non-caloric sweetener was used and significantly reduced when sucrose consumption was corrected for body weight. What is more, the length of food and water deprivation was found to confound the effect. The effect was reversed when the stressed rats were treated with antidepressants. Methodological strategies meant to control for recognized sources of bias when conducting the test were often missing, and so was a clear and complete report of essential study information. Our results indicate that not only is food and water deprivation before the test unnecessary, but not recommended. Even in absence of long fasting, we found evidence of an additional effect on sweet consumption that is unrelated to anhedonia. Without properly controlling for non-hedonic drivers of consumption, the test is unreliable as a proxy measure of anhedonia. Strengthening the methodological rigor and addressing the confounding effect of metabolic factors in the sucrose preference test prevents misleading conclusions that harm the translatability of the associated research and perpetuates the use of animals for little gain.

animal behavior and cognition↗

Hair glucocorticoids are not a historical marker of stress - exploring the time-scale of corticosterone incorporation into hairs in a rat model

Hair glucocorticoids are increasingly popular biomarkers, used across numerous research fields as a measure of stress. Although they are suggested to be a proxy of the average HPA axis activity spanning a period of weeks or months into the past, this theory has never been tested. In the present study, adrenalectomized rats with no endogenous (adrenal) glucocorticoid production were used to study how circulating glucocorticoid levels would be reflected in the glucocorticoid levels found in hair samples. By dosing the animals daily with high levels of corticosterone for seven days, while sampling hairs before, during, and after treatments, a timeline for glucocorticoid uptake into hairs was constructed. This kinetic profile was compared to two hypothetical models, and the theory that hair glucocorticoids are a record of historical stress had to be rejected. Corticosterone concentrations in hairs were found to increase within three hours of the first injection, the highest concentrations were found on the seventh day of treatments, and the decrease in concentrations post-treatment suggests rapid elimination. We speculate that hair glucocorticoid levels can only be used to characterize a stress-response for a few days following a postulated stressor. An updated model, where glucocorticoids diffuse into, along, and out of hairs needs to be adopted to reconcile the experimentally obtained data. The inescapable consequence of this updated model is that hair glucocorticoids become a marker of - and can only be used to study - recent, or ongoing, stress, as opposed to historical events, weeks or months in the past.

physiology↗