The prevalence of chronic widespread pain (CWP) in individuals infected with the human immunodeficiency virus (HIV-1) includes regional and widespread musculoskeletal pain of neuropathic and inflammatory nature. HIV-related CWP leads to 10x greater odds of functional impairment. However, the specific mechanisms that contribute to CWP in HIV are not understood. Thus, pharmacological and non-pharmacological approaches to mitigate CWP have had minimal benefits, contributing to an overreliance on opioids and alarming rise in addiction and overdose. The overall objective of this study is to address the gap in the knowledge of the pathogenesis of HIV-related CWP. Specifically, the role of impaired endogenous opioid synthesis/release from leukocytes in people with HIV (PWH) who self-report CWP will be explored. Leukocytes (neutrophils, monocytes/macrophages, and lymphocytes) are a rich source of opioid peptides (Met-enkephalin, dynorphin A, β-endorphin) that inhibit nociception by binding to peripheral opioid receptors. Therefore, to establish whether decreased peripheral opioid peptides correlate with experimental pain measures in PWH with self-reported CWP, quantitative sensory testing (QST) will be completed before and after administration of methylnaltrexone bromide (RELISTOR), a clinically available, peripherally acting opioid receptor antagonist.
To determine if decreased production or release of endogenous opioid peptides by peripheral immune cells contributes to hypersensitivity in people with HIV