Funded Projects

Masticatory and spontaneous pain associated with temporomandibular joint disorders (TMJD) is a significant contributor to orofacial pain, and current treatments for TMJD pain are unsatisfactory. Pain-related transient receptor potential (TRP) channels, expressed by trigeminal ganglion (TG) sensory neurons, have been implicated in both acute and chronic pain and represent possible targets for anti-pain strategies. Using bite force metrics, we found TMJ inflammation-induced masticatory pain to be significantly, but not fully, reversed in Trpv4 knockout mice, suggesting the residual pain might be mediated by other pain-TRPs. Our gene expression studies demonstrated that TRPV1 and TRPA1 were up-regulated in the TG in response to TMJ inflammation in a Trpv4-dependent manner. We hypothesize that TRPV1 and TRPA1, like TRPV4, contribute to TMJ pain. Our specific aims will examine the contribution of TRPV1, TRPV4, and TRPA1 to pathogenesis of TMJD pathologic pain including assessment of the role of neurogenic inflammation.

African American adults are less likely to receive analgesics, particularly opioids. Research in the pediatric surgical population is limited, but the pattern of disparate use of opioids appears consistent with adults. Furthermore, adolescent access to prescribed opioids has increased, both through physician prescribing and misuse of medications prescribed to family members or friends. This study will explore the interrelated impacts of policy, clinical need, and sociodemographic factors by combining Medicaid claims and electronic health record data with findings from a statewide opioid policy inventory. We will focus on discharge prescribing of opioids in three high-volume pediatric surgical procedures: tonsillectomy/adenoidectomy, supracondylar fracture, and appendectomy. We aim to 1) determine the extent of racial disparities in postoperative discharge opioid prescribing since the 2011 onset of enhanced opioid prescription reduction activities and 2) develop an expanded model to assess the linkage between differential opioid use for pediatric postoperative pain and opioid use-related outcomes.

An International Cooperative Biodiversity Group with an interdisciplinary leadership team of physicians, pharmacologists, evolutionary biologists, and chemists will discover and develop therapeutic agents produced by Brazilian symbiotic bacteria. The team will target three therapeutic areas: 1) infectious fungal pathogens, 2) Chagas disease and leishmaniasis, and 3) cancers of the blood. All three areas represent major threats to human health that need to be addressed with new therapeutic agents. Internationally, invasive fungal diseases kill more people than malaria or TB, while Chagas disease imposes a special burden on Brazil, killing as many Brazilians as TB. Leishmaniasis has now passed Chagas disease in the Brazilian population. Despite major improvements in cancer chemotherapy, cancer is projected to result in 8 million deaths internationally this year (13% of all deaths, WHO) and an estimated 13 million per year by 2030.

Functional selectivity is a term used to describe the ability of drugs to differentially regulate the activity of multiple signaling cascades coupled to the receptor. The underlying mechanism for functional selectivity is based upon the formation of ligand-specific receptor conformations that are dependent upon ligand structure. Functional selectivity has the potential to revitalize the drug discovery/development process. Ligands with high efficacy for specific signaling pathways (or specific patterns of signaling) that mediate beneficial effects, and with minimal activity at pathways that lead to adverse effects, are expected to have improved therapeutic efficacy. We propose to demonstrate that ligand efficacy for specific signaling pathways associated with antinociception can be finely tuned by structural modifications to a ligand. We propose to use U50,488 and Salvinorin-A (Sal-A) as scaffolds to develop functionally selective analogs that maintain high efficacy for signaling pathways that lead to antinociception and minimize activity toward anti-antinociceptive signaling pathways.

Cesarean deliveries are the most commonly performed surgical procedure in the United States. Opioids are almost universally used for post-cesarean analgesia management. Studies suggest that most women are prescribed more tablets at discharge than needed. These often go unused, providing an important reservoir contributing to the opioid crisis. Physicians struggle to prescribe and dose postoperative opioids appropriately while tackling the real needs of acute pain from surgery. Without literature to guide obstetric providers on appropriate amounts of opioids to prescribe upon discharge, actual prescription amounts nationally vary widely by up to 65 tablets. To improve post-cesarean opioid prescribing practices without compromising pain management, the study will test an individualized, patient-empowered approach for pain management and opioid prescription quantity. This is a noninferiority randomized trial of 5,500 women with a cesarean delivery who will be randomized prior to discharge.

Fibromyalgia (FM) is a chronic pain condition characterized by widespread musculoskeletal pain, tenderness, and stiffness associated with fatigue and sleep disturbance. The investigators have recently completed a trial that demonstrated efficacy of active transcutaneous electrical nerve stimulation (TENS) compared with placebo TENS or no treatment in women with FM. While physical therapists are trained in using TENS, it is underused in clinical practice. This application proposes a pragmatic clinical trial of TENS for patients with FM to determine if the addition of TENS to physical therapy (PT) reduces pain, increases PT adherence, and helps achieve functional goals with less drug use. This study will address the critical need for strategies to implement effective nonpharmacologic treatments for FM. Successful completion of this trial will provide generalizable effectiveness data for referring providers, physical therapists, and insurers and will inform future pragmatic trials of nonpharmacologic treatments conducted in PT practices.

Initial studies using positron emission tomography (PET) with [11C] carfentanil, a selective radiotracer for ?-opioid receptor (?OR), have demonstrated that there is a decrease in thalamic µOR availability (non-displaceable binding potential BPND) in the brains of TMD patients during masseteric pain compared to healthy controls. ?-opioid neurotransmission is arguably one of the mechanisms most centrally involved in pain regulation and experience. The main goals of our study are: first, to exploit the ?-opioidergic dysfunction in vivo in TMD patients compared to healthy controls; second, to determine whether 10 daily sessions of non-invasive and precise M1 HD-tDCS have a modulatory effect on clinical and experimental pain measures in TMD patients; and third, to investigate whether repetitive active M1 HD-tDCS induces/reverts ?OR BPND changes in the thalamus and other pain-related regions and whether those changes are correlated with TMD pain measures.

To enhance availability of cognitive behavioral therapy for chronic pain (CBT-CP), this study will 1) refine strategies to identify and recruit patients, finalize intervention procedures, and ensure data infrastructure and quality; 2) determine the effectiveness of online and telephonic CBT-CP on patients and pain severity and secondary outcomes, including depression, sleep, quality of life, and pain-related health care utilization, from the electronic health record; and 3) assess the cost and incremental cost-effectiveness of online and telephonic CBT-CP compared with usual care. Eligible participants will be randomized to one of two painTRAINER interventions or usual care. Interventions will be eight weekly 45-minute sessions of the online program or telehealth-style phone coaching by trained behavioral health specialists. Self-reported pain severity and secondary outcomes will be assessed at baseline and at three, six, and 12 months.

Genomic medicine offers hope for improved diagnostic methods and for more effective, patient-specific therapies. Genome-wide associated studies (GWAS) elucidate genetic markers that improve clinical understanding of risks and mechanisms for many diseases and conditions and that may ultimately guide diagnosis and therapy on a patient-specific basis. Previous phenome-wide association studies (PheWAS) established a systematic and efficient approach to identifying novel disease-variant associations and discovering pleiotropy using electronic health records (EHRs). This proposal will develop novel methods to identify associations based on patterns of phenotypes using a phenotype risk score (PheRS) methodology to systematically search for the influence of Mendelian disease variants on common disease. By doing so, it also creates a way to assess pathogenicity for rare variants and will identify patients at highest risk of having undiagnosed Mendelian disease. The project is enabled by large DNA biobanks coupled to de-identified copies of EHR.

Spinal cord injury (SCI) impairs sensory transmission and leads to chronic, debilitating neuropathic pain. While our understanding of the development of chronic pain has improved, the available therapeutics provide limited relief. We will examine the peripheral immune and inflammatory response. Secondary inflammation in response to SCI is a series of temporally ordered events: an acute, transient upregulation of chemokines, followed by the recruitment of monocytes/macrophages and generation of an inflammatory environment at the lesion site in the spinal cord, but also surrounding primary nociceptors in the dorsal root ganglia (DRG). These events precede neuropathic pain development. Previous work indicates that after SCI, macrophage presence in the DRG correlates with neuropathic pain. We propose to study: 1) whether the phenotype of macrophages that infiltrate the DRG is different than those that persist chronically after SCI and 2) how manipulation of macrophage phenotype affects nociceptor activity and pain development.

An important component of neuropathic pain is spontaneous or ongoing pain, such as burning pain or intermittent paroxysms of sharp and shooting pain, which may result from abnormal spontaneous activity in sensory nerves. However, due to technical limitations, spontaneous activity in sensory neurons in vivo has not been well studied. Using in vivo imaging in genetically-modified mice, preliminary findings identified spontaneously-firing clusters of neurons formed within the dorsal root ganglia (DRG) after traumatic nerve injury that exhibits increased spontaneous pain behaviors. Furthermore, preliminary evidence has been collected that cluster firing may be related to abnormal sympathetic sprouting in the sensory ganglia. This project will test the hypothesis that cluster firing is triggered by abnormal sympathetic inputs to sensory neurons, and that it underpins spontaneous paroxysmal pain in neuropathic pain models. Findings from this project will identify potential novel therapeutic targets for the treatment of neuropathic pain.

EPPIC-Net will provide a robust and readily accessible infrastructure for the rapid implementation and performance of high-quality comprehensive studies of patients with well-defined pain conditions, and the rapid design and performance of high-quality Phase 2 clinical trials to test promising novel therapeutics for pain. Using the Hospital of the University of Pennsylvania as a hub and five additional centers that are part of the UPenn Health System and the Children’s Hospital of Philadelphia (CHOP) as spokes, studies will be conducted as designed by the expertise of the EPPIC Network, which intends to bring intense focus to relatively small numbers of patients with clinically well-defined pain conditions and high unmet therapeutic needs. The UPenn Specialized Clinical Center (SCC) will test novel, efficient study designs including adaptive and platform designs, validation studies of biomarkers, and biomarker-informed proof of principle or target engagement studies in Phase 2 trials of interventions from academic and industry partners.

This project will examine the association between end plate pathology and chronic low back pain (cLBP) and improve patient selection by developing and translating new imaging tools, technologies, and/or methods (iTTM) that provide accurate, noninvasive measures of end plate pathologies. A search for clinically relevant biomarkers of end plate pathology will focus on novel imaging measures of end plate bone marrow lesion (BML) severity with IDEAL MRI and cartilage endplate (CEP) fibrosis/damage with UTE MRI, assess interactions with paraspinal muscles, and identify metrics that associate with pain, disability, and degeneration. The research will refine imaging and post-processing methodologies by leveraging and expanding existing cross-sectional cohorts and then deploy and validate the new end plate iTTM to other BACPAC sites to test the most promising metrics’ clinical utility. These studies will provide validated iTTM that are useful for addressing the end plates pathology’s role in cLBP, identifying sub-phenotypes, discovering pain mechanisms, uncovering treatment targets, and selecting patients.