Biology subjects

Goddard, C. M.

Publications and source records attributed to Goddard, C. M..

3 recordsLinked to original sources

bioRxiv2024

The neurovascular coupling response of the aged brain is brain-state dependent.

Brain aging lead to reduced cerebral blood flow and cognitive decline, but how normal aging affects neurovascular coupling (NVC) in the awake brain is unclear. Here, we investigated NVC in relation to calcium changes in vascular mural cells (VMCs) in awake adult and aged mice. We show that NVC responses are reduced and prolonged in the aged brain and that this is more pronounced at the capillary level than in arterioles. However, the overall NVC response, measured as the time integral of vasodilation, is the same in two age groups. In adult, but not in aged mice, the NVC response correlated with Ca2+ signaling in VMCs, while the overall Ca2+ kinetics were slower in aged than in adult mice. In particular, the rate of Ca2+ transport, and the Ca2+ sensitivity of VMCs were reduced in aged mice, explaining the reduced and prolonged vasodilation. Spontaneous locomotion was less frequent and reduced in aged mice as compared to young adult mice, and this was reflected in the slow but prolonged NVC and vascular Ca2+ responses. Taken together, our data characterize the NVC in the aged awake brain as slow but prolonged, and underscoring the importance of brain state in understanding age-related mechanisms.

neuroscience↗

bioRxiv2024

Venom-inspired somatostatin receptor 4 (SSTR4) agonists as new drug leads for peripheral pain conditions

Persistent pain affects one in five people worldwide, often with severely debilitating consequences. Current treatment options, which can be effective for mild or acute pain, are ill-suited for moderate-to-severe persistent pain, resulting in an urgent need for new therapeutics. In recent years, the somatostatin receptor 4 (SSTR4), which is expressed in sensory neurons of the peripheral nervous system, has emerged as a promising target for pain relief. However, the presence of several closely related receptors with similar ligand-binding surfaces complicates the design of receptor-specific agonists. In this study, we report the discovery of a potent and selective SSTR4 peptide, consomatin Fj1, derived from extensive venom gene datasets from marine cone snails. Consomatin Fj1 is a mimetic of the endogenous hormone somatostatin and contains a minimized binding motif that provides stability and drives peptide selectivity. Peripheral administration of synthetic consomatin Fj1 provided analgesia in mouse models of postoperative and neuropathic pain. Using structure-activity studies, we designed and functionally evaluated several Fj1 analogs, resulting in compounds with improved potency and selectivity. Our findings present a novel avenue for addressing persistent pain through the design of venom-inspired SSTR4-selective pain therapeutics. One Sentence SummaryVenom peptides from predatory marine mollusks provide new leads for treating peripheral pain conditions through a non-opioid target.

pharmacology and toxicology↗

bioRxiv2023

mPD5, an efficacious PICK1 inhibitor for treating chronic pain

Chronic pain is a complex, debilitating, and escalating health problem worldwide, impacting one in five adults. Current treatment is compromised by dose-limiting side effects including high abuse liability, loss of ability to function socially and professionally, fatigue, drowsiness, and apathy. PICK1 has emerged as a promising target for the treatment of chronic pain conditions. Here, we develop and characterize a cell-permeable fatty acid conjugated bivalent peptide inhibitor of PICK1 and assess its effects on acute and chronic pain. The myristoylated myr-NPEG4-(HWLKV)2, (mPD5), self-assembles into core-shell micelles that provide favourable pharmacodynamic properties and relieves ongoing and evoked mechanical hypersensitivity, thermal hypersensitivity as well as anxio-depressive symptoms in mouse models of neuropathic and inflammatory pain following subcutaneous administration. No overt no side effects were associated with mPD5 administration, and it has no effect on acute nociception. Finally, neuropathic pain is relieved far into the chronic phase (18 weeks post SNI surgery) and while the effect of a single injection ceases after a few hours, repeated administration provides pain relief lasting up to 20 hours after the last injection.

pharmacology and toxicology↗