Funded Projects

Inhaled nitrous oxide, N₂O, is used in emergency departments in Europe to treat pain associated with sickle cell disease as well as for labor, painful fractures, and to manage serious gynecological pain. It is not a viable therapeutic option for home use for reasons such as poor dosing control, potential inhalation equipment issues, and variability in patient ventilation and lung absorption. This project seeks to optimize, characterize, and develop an oral formulation of N₂O that could be used by patients at home for unpredictable and severe episodes of pain associated sickle cell disease. Once developed, the new oral formulation of N₂O will be evaluated to determine whether it or an optimized version is ready for more clinical testing.

The medication monomethyl fumarate, approved for treating multiple sclerosis, has pain-relieving properties, but it also has side effects that affect the digestive tract and decrease levels of white blood cells, a problem known as leukopenia. This project will limit the availability of monomethyl fumarate to areas in the central nervous system associated with pain. Targeting the delivery of this drug to pain-related regions may improve its safety profile for treating neuropathic pain.

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.

Neuropathic corneal pain (NCP) causes patients to have severe discomfort and a compromised quality of life (QoL). The lack of signs observed by standard examination has resulted in misdiagnosis as dry eye disease (DED). An optical biopsy using laser in vivo confocal microscopy (IVCM) revealed that microneuromas (bulbs at the ends of severed nerves caused by buildup of molecular constituents) are present in NCP but not DED and may serve as a biomarker for NCP. The aims are to (1) use a database of more than 2,000 DED/NCP subjects and more than 500,000 IVCM images to confirm that the presence of microneuromas is an appropriate biomarker for NCP, (2) provide biological validation of microneuromas, (3) develop a validated artificial intelligence (AI) program for automated identification of microneuromas, and (4) establish the clinical utility of microneuromas observed by IVCM as a biomarker for NCP in a prospective, multicenter study.

The Philippine Mollusk Symbiont International Cooperative Biodiversity Group harnesses the vast biodiversity of the Philippines to discover new drugs to treat bacterial infections, parasitic infections, pain, and other neurological conditions and cancer, all of which are serious health problems in both the Philippines and the United States. The Republic of the Philippines represents a unique nexus of exceptional biodiversity, dense human population with pressing societal needs, consequent urgent need for conservation, and government commitment to education and technology to harness national human and natural resources for a sustainable future. Mollusks are one of the most diverse groups of marine animals, and their associated bacteria represent an unexplored trove of chemical diversity. Researchers will use an increasing understanding of the interactions between mollusk symbionts and their hosts to discover the most novel and useful molecules. The project will document and describe Philippine mollusk biodiversity and support training and infrastructure that provide the foundation for conservation of Philippine biodiversity.

The cannabis plant contains many active compounds known collectively as cannabinoids that have been shown to possess analgesic and anti-inflammatory properties. These compounds exert their biological activity, in part, through the cannabinoid receptor. The cannabinoid receptor is a member of a class of proteins known as G-protein coupled receptors (GPCRs). This study will test whether a GPCR with unknown biological function, called Gpr149, has a role in the activity of cannabinoids. The study will identify and characterize Gpr149 expression in mouse cells, and deeply characterize the action of minor cannabinoids, endocannabinoids and products of inflammation to modulate Gpr149. This research will provide insight into the analgesic and anti-inflammatory action of minor cannabinoids and into the role of Gpr149 in nociception and the sensitization of nociceptors to inflammatory mediators.

This project will build overdose models for fentanyl, methadone, codeine, and morphine in a multi-organ system and evaluate the acute and repeat dose, or chronic effects, of overdose treatments as well as off-target toxicity. Researchers developed a system using human cells in a pumpless multi-organ platform that allows continuous recirculation of a blood surrogate for up to 28 days. They will develop two overdose models for male and female phenotypes based on pre-B?tzinger Complex neurons and will integrate functional immune components that enable organ-specific or systemic monocyte actuation. Models for cardiomyopathy and infection will be utilized. Researchers will establish a pharmacokinetic/pharmacodynamic model of overdose and treatment to enable prediction for a range of variables. We will use a serum-free medium with microelectrode arrays and cantilever systems integrated on chip that allow noninvasive electronic and mechanical readouts of organ function.

Immune checkpoint proteins regulate the immune system to prevent it from indiscriminately attacking cells. Some cancers activate these immune checkpoints to avoid attack, and drugs that target certain immune checkpoints are approved for cancer treatment. The same pathway may also be involved in pain because immune checkpoint proteins, such as programmed death 1 (PD-1) and the molecule that binds to it (programmed death ligand 1 [PD-L1]), also are found in sensory neurons, microglia, and macrophages. This project will investigate PD-1/PD-L1 in different cell populations to determine their contribution to pain and to the effects of opioids such as morphine. This knowledge may help identify new drugs for pain management that modify immune checkpoint activity.

For patients with neuropathic pain refractory to therapy using small molecules, modulation of specific neural structures in the central or peripheral nervous system can provide effective alternative treatments. While current Food and Drug Administration–approved devices for dorsal root ganglion (DRG) stimulation are safe and effective, there have been an unfortunate number of adverse events associated with pulse generator infections and lead migration. The research team will develop a wireless, millimeter-sized nerve stimulator that can be delivered through the vasculature and stimulate the DRG to alleviate symptoms of neuropathic pain and the associated minimally invasive delivery method. This endovascular nerve stimulation (EVNS) system depends on development and integration of key novel technologies into an endovascular stent. The magnetoelectric transducers and electronic circuits will convert wireless power and data into stimulus patterns that can trigger neural activity in the DRG via miniature electrodes. After chronic demonstration of safety and functionality in large animal models, the team will prepare for regulatory discussions with the FDA. If successful, the EVNS will provide a technology platform for treating other neuropathic pain syndromes. 

Opioids and other addictive substances have powerful rewarding properties that drive the development of addiction. They also have aversive properties that motivate their avoidance and protect against addiction. This project will explore the role of Type 2 Taste Receptor proteins (Tas2Rs or T2Rs) in regulating the aversive properties of opioids, potentially establishing an entirely new class of receptors that can be targeted for the development of novel addiction therapeutics.

Neuropilin 1 receptor (NRP1) is a protein receptor that is active in neurons and is hypothesized to be a key mediator of sensory neuron sensitization that can lead to pain. This project will study the cellular mechanisms by which NRP1 leads to sensitization and which cell types—sensory neurons, microglia, or both—are responsible for NRP1’s role in pain. The findings can help validate NRP1 in sensory neurons and the spinal cord as a target to treat pain following nerve injury.

Chronic pain is a debilitating condition for which there is a pressing need for safe, effective treatments. Neurostimulation therapies that target nerve structures such as the dorsal root ganglion (DRG) and the spinal cord, have shown promising results for treating chronic pain, but researchers don’t know how they work. This project focuses on two prevailing models used to explain the therapeutic effects of neurostimulation: the gate-control model in which pain signals are blocked from reaching the brain and the T-junction filtering model in which pain signals are blocked from reaching the spinal cord. Strategies will include innovative behavioral, electrophysiological, imaging, and computational modeling techniques. The results of these studies will help explain why neurostimulation therapies work and potentially offer new treatment strategies for improved pain relief.

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.