Funded Projects

This International Cooperative Biodiversity Group application aims to discover and develop small molecule drug leads from cultured marine microbes and diverse coral reef organisms collected from Fiji and the Solomon Islands. Drug discovery efforts will focus on four major disease areas of relevance to the United States and low- and middle-income countries: infectious disease, including tuberculosis and drug-resistant pathogens; neglected tropical diseases, including hookworms and roundworms; cancer; and neurodegenerative and central nervous system disorders. Screening in these therapeutic areas will be performed in collaboration with two major pharmaceutical companies, two highly respected academic groups, and various testing centers and government resources that are available to facilitate drug discovery and development. The acquisition of source material for this program will be linked to biotic surveys, informed by ecological investigations addressing the chemical mediation of biotic interactions, and enriched using ecology-based strategies designed to maximize secondary metabolite production and detection.

Spinal cord stimulators (SCS) and related devices are commonly used for hard-to-treat pain conditions, but how they work remains unclear. This knowledge is important for improving device design and stimulation patterns, as well as for determining which patients will benefit. Through a series of clinical studies in patients with SCS devices, this project will explore the hypothesis that SCS devices reduce pain by changing the excitability of peripheral sensory nerve fibers in the spinal cord. The results should guide development of biomarkers to advance research further.

Peripheral nerve injury-induced upregulation of three axonal guidance phosphoproteins correlates with the development of neuropathic pain through an unidentified mechanism: 1) collapsin response mediator protein 2 (CRMP2); 2) the N-type voltage-gated calcium (CaV2.2); 3) the NaV1.7 voltage-gated sodium channel. Injury induced phosphorylated-CRMP2/CaV2.2 and phosphorylated-CRMP2/NaV1.7 upregulation in the sensory pathway may promote abnormal excitatory synaptic transmission in spinal cord that leads to neuropathic pain states. This project will validate CRMP2 phosphorylation as a novel target in neuropathic pain using innovative tools. Examples include a genetic approach (crmp2S522A) in mice as well as a non-opioid pharmacological approach (a novel CRMP2-phsphorylation targeting compound). Demonstrating that inhibition of CRMP2 phosphorylation reverses or prevents neuropathic pain will promote the discovery and validation of a novel therapeutic target (CRMP2-phosphorylation) to facilitate the development of novel pain therapeutics.

This project aims to develop and clinically validate a 64-channel spinal cord stimulation therapy for treating chronic neuropathic pain of the lower extremities, groin, and lower back. With an increased channel count and the ability to precisely target medial and lateral structures of the spinal cord, the system will treat chronic pain with greater efficacy and reduced side effects. This project will pursue a safe, effective, and non-addictive treatment for neuropathic pain through the testing of enhanced HD64 active leads to be manufactured under GMP regulations. The leads will then undergo electrical, mechanical, biocompatibility, and sterilization testing before being tested in a 10-subject early feasibility study.

The research team will develop HD64—a high-resolution, 64-channel spinal cord stimulation therapy to provide more pain relief for those suffering from chronic neuropathic pain and opioid dependence. HD64 provides an ultra-thin conformal blanket of stimulation contacts across the width of the spinal cord and enables more precise targeting of the lateral structures of the spinal cord to enhance pain relief. A cadaveric pilot run followed by a non-significant risk intraoperative study will be performed to inform the design parameters of HD64 arrays. The study will evaluate activation of medial and lateral spinal targets. At the end of Phase 1, the clinical feasibility of HD64 surgical leads will be established. In Phase 2, researchers will develop an external active lead pulse generator and charger. They will perform an early feasibility study human trial using active HD64 and mechanical and electrical design verification testing and chronic safety studies in large animals.

Currently, there are no adequate therapies for abdominal pain in patients with Irritable Bowel Syndrome (IBS), a gastrointestinal disorder affecting 14-20% of the US population. More than 40% of IBS patients regularly use opioid narcotics. An alternative treatment for IBS that has been shown to be an effective pain management strategy is electroacupuncture. However its drawbacks include infrequent administration, unclear mechanistic understanding, and lack of methodology optimization. This study will use a noninvasive method of transcutaneous electrical acustimulation (TEA) by replacing needles with surface electrodes and testing acupoints that target peripheral nerves. Based on prior mechanistic and clinical studies, two stimulation parameters and effective acupoints will be tested. In the UG3 phase, the TEA device and a cell phone app will be optimized for use in IBS abdominal pain, and an acute clinical study will determine the best stimulation locations and parameters. During the UH3 phase, an early feasibility clinical study will be performed in 160 IBS patients in treating abdominal pain. Participants will self-administer the therapy at home/work and will be randomized across four treatment groups to determine the therapeutic potential of the TEA system.

This project will identify molecular characteristics of human sensory neurons and non-neuronal cells from the human dorsal root ganglia. This structure located outside the spinal cord is integrally involved in communicating pain signals to and from the brain. The research will use molecular approaches to characterize tissues obtained from organ donors and in patients who experience chronic pain. The findings will also help generate a connectivity map, or “connectome,” of nerve cell connections between the dorsal root ganglia of the spinal cord and the brain.

This project focuses on identifying and validating a new central analgesic circuit in the brain, based on a highly innovative hypothesis that the strong analgesic effects of general anesthesia (GA) are in part carried out by GA-mediated activation of the endogenous analgesic circuits. Preliminary discovery studies found that a subset of GABAergic neurons located in the central amygdala (CeA) become strongly activated and express high levels of the immediate early gene Fos under GA (hereafter referred to as CeAGA neurons). Furthermore, activation of these neurons exert profound pain-suppressing effects in an acute pain model and a chronic orofacial neuropathic pain model in mice. Based on these exciting preliminary findings, this project will identify and validate CeAGA neurons’ analgesic functions utilizing multiple mouse pain models. Identification of these shared common pathways that need to be suppressed by specific subtypes of CeAGA analgesic neurons will be highly critical for developing precise CeAGA-targeted therapies to treat chronic pain.

The goal of this project is to generate data and reagents that help uncover critical functions of the poorly characterized members of ion channels. It focuses on co-perturbation of ion channel genes and their interacting genetic components as opposed to singly altering ion channel genes in mouse models. This approach will validate our proteomics approaches in the most definitive manner: in vivo. We see in vivo exploration as an essential step to evaluate ion channel function. Our major aims include mapping ion channel interactions and complexes using a high-throughput proteomics platform at UCSF. These data will be interrogated using integrative approaches established by the Monarch Initiative, where biochemical interactions will be validated and prioritized for further study. Another major aim is function-centric: We use mouse models for elucidation of human disease mechanisms, where we embrace a genetic interaction scheme to uncover ion channel redundancy and polygenic effects.

The research team will develop an implantable neural stimulation system to provide natural and intuitive sensation for prosthesis users. The nerve cuff technology meets the requirements for a sensory feedback system capable of providing consistent and controlled electrical stimulation. Coupled with a multichannel implantable stimulator, this electrode array will offer substantial improvement over existing options to treat phantom limb pain (PLP). In Phase I, researchers will finalize array architectures for evaluation in cadaver studies, complete integration of electrodes with our stimulator, conduct benchtop verification of electrical and mechanical performance, send implants for third-party evaluation of system biocompatibility, and complete a Good Laboratory Practice animal study to validate safety and efficacy. In Phase II, researchers will conduct a 5-subject clinical study to test the implantable stimulation system. Each unilateral prosthesis user will be implanted for one year as researchers evaluate the safety and efficacy of this implantable device to treat PLP.

There is a continued need to discover and validate new targets for potential therapeutic strategies for effective and safe treatment of pain. This project focuses on the protein metadherin, also known as astrocyte elevated gene-1 protein (AEG-1), as a possible new target for pain treatment. Preliminary studies have shown that mice genetically engineered to lack metadherin had significantly lower inflammation and chronic pain-related behaviors. This project aims to further validate AEG-1 as a pain target and test whether reducing levels in white blood cells called macrophages might work as a therapeutic strategy to reduce chronic inflammatory and/or neuropathic pain using an innovative nanoparticle approach to target specific cells.

The clinical utility of opioids for pain treatment is limited by its risk for developing opioid usage disorders (OUD). These untoward effects impose a severe burden on society and present difficult therapeutic challenges for clinicians. We propose to extend our cerebral organoid MPS to facilitate the investigation of neuronal response to opioids and identify cellular and molecular signatures in patients vulnerable to OUD. We have assembled a team with complementary expertise in clinical characterization of OUD, cerebral organoid MPS modeling, single cell RNA-seq technology, and functional characterization of neurons in a mesolimbic reward system to test the hypothesis that midbrain MPS is a clinically relevant pre-clinical model for study of opioid usage disorder.

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.