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Introduction: The prostate is densely innervated like many visceral organs and glands. However, studies to date have focused on sympathetic and parasympathetic nerves and little attention has been given to the presence or function of sensory nerves in the prostate. Recent studies have highlighted a role for sensory nerves beyond perception of noxious stimuli, as anterograde release of neuropeptides from sensory nerves can affect vascular tone and local immune responses. Methods: To identify the degree of sensory innervation in the prostate, we utilized state-of-the-art tissue clearing and microscopy to visualize sensory innervation in the different lobes of the mouse prostate. To determine whether sensory nerves have a role in regulating proliferation within the prostate, we used an intersectional genetic and toxin approach to ablate peptidergic sensory nerves systemically. Results: We found that sensory neurons are abundant in the prostate both in nerve bundles along the vasculature and as independent nerve fibers wrapped around prostatic acini in a net-like fashion. In addition to the dense innervation of the prostate, we found that Calca haploinsufficiency, the genotype control for our intersectional ablation model, results in a diminished level of Ki67 staining in the stromal compartment of the dorsal lobe and a diminishing Ki67 trend in other lobes. Discussion: These findings suggest that sensory neurons might have developmental or homeostatic effects within the prostate. Further studies are warranted to assess the role of sensory neurons and the sensory neuropeptides on prostatic development and on proliferation in the presence of pro-inflammatory stimuli such as bacterial infection or tumor cells. [ABSTRACT FROM AUTHOR]

We discuss and present new data regarding the physiological and molecular mechanisms of nuclear receptor activation in pain control, with a particular emphasis on non-genomic effects of ligands at peroxisome proliferator-activated receptor (PPAR), GPR30, and classical estrogen receptors. PPARalpha agonists rapidly reduce both acute and chronic pain in a number of pain assays. These effects precede transcriptional anti-inflammatory actions, and are mediated in part by IK(ca) and BK(ca) channels on DRG neurons. In contrast to the peripheral site of action of PPARalpha ligands, the dorsal horn supports the expression of PPARgamma. Intrathecal administration of PPARgamma ligands rapidly (< or =5 min) attenuated mechanical and thermal hypersensitivity associated with nerve injury in a dose-dependent manner that could be blocked with PPARgamma antagonists. By contrast, a PPARgamma antagonist itself rapidly increased the mechanical allodynia associated with nerve injury. These data suggest that ligand-dependent, non-genomic activation of spinal PPARgamma decreases behavioral signs of inflammatory and neuropathic pain. We also report that the GPR30 is expressed on cultured sensory neurons, that activation of the receptor elicits signaling to increase calcium accumulation. This signaling may contribute to increased neuronal sensitivity as treatment with the GPR30 agonist induces hyperalgesia. Finally, application of the membrane-impermeable 17beta-E(2)-BSA rapidly (within 15 min) enhanced BK-stimulated inositol phosphate (IP) accumulation and PGE(2)-mediated cAMP accumulation in trigeminal ganglion cultures. We conclude that nuclear receptor ligands may operate through rapid, non-genomic mechanisms to modulate inflammatory and neuropathic pain.

The use of N-type voltage-gated calcium channel (CaV2.2) blockers to treat pain is limited by many physiological side effects. Here we report that inflammatory and neuropathic hypersensitivity can be suppressed by inhibiting the binding of collapsin response mediator protein 2 (CRMP-2) to CaV2.2 and thereby reducing channel function. A peptide of CRMP-2 fused to the HIV transactivator of transcription (TAT) protein (TAT-CBD3) decreased neuropeptide release from sensory neurons and excitatory synaptic transmission in dorsal horn neurons, reduced meningeal blood flow, reduced nocifensive behavior induced by formalin injection or corneal capsaicin application and reversed neuropathic hypersensitivity produced by an antiretroviral drug. TAT-CBD3 was mildly anxiolytic without affecting memory retrieval, sensorimotor function or depression. At doses tenfold higher than that required to reduce hypersensitivity in vivo, TAT-CBD3 caused a transient episode of tail kinking and body contortion. By preventing CRMP-2-mediated enhancement of CaV2.2 function, TAT-CBD3 alleviated inflammatory and neuropathic hypersensitivity, an approach that may prove useful in managing chronic pain. [ABSTRACT FROM AUTHOR]

Introduction: The prostate is densely innervated like many visceral organs and glands. However, studies to date have focused on sympathetic and parasympathetic nerves and little attention has been given to the presence or function of sensory nerves in the prostate. Recent studies have highlighted a role for sensory nerves beyond perception of noxious stimuli, as anterograde release of neuropeptides from sensory nerves can affect vascular tone and local immune responses., Methods: To identify the degree of sensory innervation in the prostate, we utilized state-of-the-art tissue clearing and microscopy to visualize sensory innervation in the different lobes of the mouse prostate. To determine whether sensory nerves have a role in regulating proliferation within the prostate, we used an intersectional genetic and toxin approach to ablate peptidergic sensory nerves systemically., Results: We found that sensory neurons are abundant in the prostate both in nerve bundles along the vasculature and as independent nerve fibers wrapped around prostatic acini in a net-like fashion. In addition to the dense innervation of the prostate, we found that Calca haploinsufficiency, the genotype control for our intersectional ablation model, results in a diminished level of Ki67 staining in the stromal compartment of the dorsal lobe and a diminishing Ki67 trend in other lobes., Discussion: These findings suggest that sensory neurons might have developmental or homeostatic effects within the prostate. Further studies are warranted to assess the role of sensory neurons and the sensory neuropeptides on prostatic development and on proliferation in the presence of pro-inflammatory stimuli such as bacterial infection or tumor cells., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xia, Jerde and Fehrenbacher.)

A role for oxidative stress in the etiology of myriad neuropathologies is well accepted. However, the specific effects of oxidative DNA damage in the onset or promotion of neuronal dysfunction have been less studied. In our recent publication by Behrouzi et al . (Oxidative DNA Damage and Cisplatin Neurotoxicity Is Exacerbated by Inhibition of OGG1 Glycosylase Activity and APE1 Endonuclease Activity in Sensory Neurons), inhibition of enzymes that play a role in repairing oxidative DNA damage exacerbated neurotoxic effects of the chemotherapeutic agent, cisplatin. In this Commentary, we aim to expand on the contribution of oxidative DNA damage to other neuropathologies within the peripheral and central nervous systems, including irritable bowel disease, aging and Alzheimer's disease, amyotrophic lateral sclerosis, and other neurodegenerative diseases. Consistently, clinical neuropathology and disease progression correlates with increases in oxidative DNA damage within clinical biopsies. Progress in animal models of these diseases has elucidated a causative role for oxidative DNA damage in disease progression, as dampening the DNA repair response exacerbates disease, whereas promoting DNA repair mitigates disease. Overall, this Commentary highlights the importance of expanding our studies on oxidative DNA damage in the nervous system, as enhancing oxidative DNA repair might prove to be a potential therapeutic target for the mitigation of neurodegeneration.