Funded Projects

This project will design and test optimized temporal patterns of stimulation to improve the efficacy of commercially available spinal cord stimulation (SCS) systems to treat chronic neuropathic pain. Researchers will build upon a validated biophysical model of the effects of SCS on sensory signal processing in neurons within the dorsal horn of the spinal cord to better understand how to improve the electrical stimulus patterns applied to the spinal cord. They will use sensitivity analyses to determine the robustness of stimulation patterns to variations in electrode positioning, selectivity of stimulation, and biophysical properties of the dorsal horn neural network. Researchers will demonstrate improvements from these new stimulus patterns by 1) measuring their effects on pain-related behavioral outcomes in a rat model of chronic neuropathic pain and by 2) quantifying the effects of optimized temporal patterns on spinal cord neuron activity. The outcome will be mechanistically derived and validated stimulus patterns that are significantly more efficacious than the phenomenologically derived standard of care patterns; these patterns could be implemented with either a software update or minor hardware modifications to existing SCS products.

Approximately 3.6 million Americans live with an amputated extremity, and the majority of these individuals are likely to suffer from chronic post-amputation pain. There is no consensus as to a recommended therapy for such pain, and many treatments do not provide sufficient pain control. Some studies have shown effective pain suppression from delivering an anesthetic agent directly to an injured nerve. This research aims to develop a device that can be implanted near the injured nerves of an amputated limb to deliver an anesthetic. Findings from this preclinical study will optimize design and delivery features to maximize its effect on pain control for as long as possible without needing a drug refill. The research is expected to advance eligibility for further testing in large animals and humans.

This project will use a variety of technologies to create a comprehensive, 3D map of how sensory neurons activate knee joints in both mice and humans. The research will use imaging techniques and molecular approaches that measure gene expression. The findings will help create a comprehensive gene expression profile map of individual cells in the nerve fibers leading to the knee, as well as describe how nerve cells and joint cells interact at the most fundamental level. This research will generate a rich anatomical and molecular resource to understand the molecular basis of joint pain and guide the development of novel pain-relieving strategies.

 Quell Therapeutics uses the Optopatch platform for making all-optical electrophysiology measurements in neurons at a throughput sufficient for phenotypic screening. Using engineered optogenetic proteins, blue and red light can be used to stimulate and record neuronal activity, respectively. Custom microscopes enable electrophysiology recordings from 100’s of individual neurons in parallel with high sensitivity and temporal resolution, a capability currently not available with any other platform screening technology. Here, researchers combine the Optopatch platform with an in vitro model of chronic pain, where dorsal root ganglion (DRG) sensory neurons are bathed in a mixture of inflammatory mediators found in the joints of osteoarthritis patients. The neurons treated with the inflammatory mixture become hyperexcitable, mimicking the anticipated cellular pain response. Investigators calculate the functional phenotype of arthritis pain, which captures the difference in action potential shape and firing rate in response to diverse stimuli. The team will screen for small molecule compounds that reverse the pain phenotype while minimizing perturbation of neuronal behavior orthogonal to the pain phenotype, the in vitro “side effects.” The highest ranking compounds will be chemically optimized and their pharmacokinetic, drug metabolism, and in vivo efficacy will be characterized. The goal is to advance therapeutic discovery for pain, which may ultimately help relieve the US opioid crisis.

The goal of this proposal is to conduct a randomized controlled trial to evaluate the comparative effectiveness of conservative behavioral and nonopioid pharmacological treatments (Phase I) and, among nonresponders, the benefits of nonsurgical procedural interventions (Phase II). Aim 1 will evaluate the effectiveness of individual and combined online cognitive behavioral therapy (painTRAINER) and pharmacologic treatment (duloxetine) in improving pain and function for knee osteoarthritis (KOA) patients compared with standard of care. Aim 2 will determine if genicular nerve radiofrequency ablation or intra-articular injection of hyaluronic acid and steroid is more effective in improving outcomes than local anesthetic nerve block or standard of care and help establish the role of these interventional treatments in the overall management of pain in KOA patients. Aim 3 will test whether clinical and psychosocial phenotypes predict short- and long-term treatment response.

Inhibitors of the epigenetic enzymes histone deacetylases (HDACs) produce analgesic responses and are therefore therapeutic targets for pain. The research team recently resolved a PET imaging agent, [11C]Martinostat, that selectively binds to a subset of HDAC enzymes. A series of initial proof-of-concept clinical validation studies will be conducted to evaluate whether [11C]Martinostat PET is a sensitive biomarker to detect the typical (axial) chronic low back pain (cLBP). The research team will validate [11C]Martinostat PET’s ability to differentiate subtypes of pain by comparing axial cLBP and other cLBP patients with radiculopathy and longitudinally study subacute LBP patients (sLBP) to investigate whether there is a unique imaging signature that differentiates patients who develop cLBP and those who recover from low back pain. Using [11C]Martinostat to understand HDAC expression changes in chronic pain patients will validate an epigenetic drug target, refine patient selection based on HDAC expression, and facilitate proof of mechanism in developing novel analgesics.

The University of Pittsburgh Low Back Pain: Biological, Biomechanical, and Behavioral Phenotypes (LB3P) Mechanistic Research Center (MRC) will to perform in-depth phenotyping of patients with chronic low back pain (cLBP), using a multimodal approach to characterize patients and provide insight into the phenotypes associated with experience of cLBP to direct targeted and improved treatments. The LB3P MRC will be formed of three Research Cores, three support cores, and one research project. This approach will leverage and integrate distinctive resources at the University of Pittsburgh laboratories to deliver quantified biomechanical, biological, and behavioral characteristics; functional assessments; and patient-reported outcomes, coupled with advanced data analytics using a novel Network Phenotyping Strategy (NPS). By eliminating isolated and disconnected approaches to treatment and focusing on personalized patient-centric approaches, this approach will yield improved outcomes and patient satisfaction.

Therapeutic virtual reality (VR) has emerged as a promising and evidence-based treatment modality for musculoskeletal pain, including chronic low back pain (cLBP). Users of VR wear a pair of goggles with a close-proximity stereoscopic screen that creates a sensation of being transported into lifelike, three-dimensional worlds. By stimulating the visual cortex while engaging other senses, VR modulates the user’s processing of nociceptive stimuli. Functional magnetic resonance imaging (fMRI) of the brain reveals that VR has similar effects on the sensory and insular cortex as opioids, and head-to-head trials show that VR achieves similar or greater analgesia as hydromorphone. Since there are few data regarding long-term efficacy and safety of VR in cLBP, this study will measure patient-reported outcomes, biometric outcomes, and opioid use in nonspecific cLBP patients under various experimental conditions using VR therapy.

There are numerous pharmacological and non-pharmacological interventions for chronic low back pain, yet no treatment is universally effective. This award supports an early career physician to develop skills to prepare for a career in clinical pain research in an environment aiming to understand patient characteristics that predict differential responses to pain interventions and thus allow for tailored treatments. This research assesses the impact of mindfulness-based stress reduction on pain interference reported by people with chronic low back pain and explores neurobiological effects of mindfulness-based stress reduction through advanced imaging and clinical assessments.

Identifying optimal chronic low back pain treatments on a patient-specific basis is an important and unresolved challenge. Tailoring interventions according to patient movement characteristics is one option. This research is characterizing patients based on spinal motion during functional tasks and daily activities and will use artificial intelligence to objectively characterize motions of the spine during both clinical assessments and day-to-day life. During clinical assessments, participants will be asked to perform functional tasks while wearing motion sensors. Data collected from the sensors will be used to identify tasks of interest, such as activities of daily living and aberrant/painful motions. An artificial intelligence approach will then interpret data collected continuously during assessment in patients’ homes over a 7-day testing period. Ultimately, this data could be used to help clinicians tailor treatments that are responsive to a patient’s real-world functional impairments.

Patients with chronic low back pain, often have depressive and anxiety symptoms and use opioids all of which are associated with stigma. In turn stigma leads to decreased treatment seeking and adherence, increased depression and pain, and poor treatment outcomes. Intersection of these health-related stigmas may have synergistic effects. This study aims to enhance the findings of a clinical trial to test antidepressant medication and Enhanced Fear Avoidance Rehabilitation in patients with chronic low back pain and high levels of depression and anxiety. The effects of these intersecting types of stigma on the efficacy of the interventions will be evaluated to better understand the needs of the patient population and to inform development of a stigma reducing intervention that can be implemented care providers.

Multiple factors, including inflammation contribute to chronic low back pain. Inflammation is mediated by numerous genes. The study aims to determine how variations in the genes encoding key inflammatory mediators impact the response of patients with chronic low back pain to physical therapy treatment. Gene variations that are known to be linked to inflammation and pain will be tested against their possible association on physical therapy treatment outcomes, to inform clinical decisions on optimal care. This study will support training in clinical research on pain within the context of the HEAL BACPAC Mechanistic Research Center. It will provide resources for a research project relevant to the parent grant and the career development of an individual in the field of pain research. The ability to identify a set of genetic variations and classify patients according to treatment response might enable use of DNA testing as a screening tool for targeted treatments for patients with CLBP.

There are numerous non-pharmacological interventions for chronic low back pain, yet no treatment is invariably effective for all. Understanding patient characteristics that predict differential responses to these non-pharmacological interventions will allow for tailored treatments to maximize positive patient impact. This supplement supports a training experience for an individual in clinical pain research, including exploring differential response to psychotherapeutic interventions. The aim of the project is to provide an extensive systematic literature review examining baseline phenotypic factors that predict differential responsiveness to the some of the most commonly used psychotherapeutic interventions for chronic low back pain.