A temporal and spatial map of axons in developing mouse prostate

Abstract

Prostate autonomic and sensory axons control glandular growth, fluid secretion, and smooth muscle contraction and are remodeled during cancer and inflammation. Morphogenetic signaling pathways reawakened during disease progression may drive this axon remodeling. These pathways are linked to proliferative activities in prostate cancer and benign prostate hyperplasia. However, little is known about which developmental signaling pathways guide axon investment into prostate. The first step in defining these pathways is pinpointing when axon subtypes first appear in prostate. We accomplished this by immunohistochemically mapping three axon subtypes (noradrenergic, cholinergic, and peptidergic) during fetal, neonatal, and adult stages of mouse prostate development. We devised a method for periprostatic axon density quantification and tested whether innervation is uniform across the proximo-distal axis of dorsal and ventral adult mouse prostate. Many axons directly interact with or innervate neuroendocrine cells in other organs, so we examined whether sensory or autonomic axons innervate neuroendocrine cells in prostate. We first detected noradrenergic, cholinergic, and peptidergic axons in prostate at embryonic day (E)14.5. Noradrenergic and cholinergic axon densities are uniform across the proximal-distal axis of adult mouse prostate while peptidergic axons are denser in the periurethral and proximal regions. Peptidergic and cholinergic axons are closely associated with prostate neuroendocrine cells whereas noradrenergic axons are not. These results provide a foundation for understanding mouse prostatic axon development and organization and provides strategies for quantifying axons during progression of prostate disease.

In utero and lactational PCB exposure drives anatomic changes in the juvenile mouse bladder

“…Multiple images (at least 2–3; encompassing the top, middle and bottom of the section) were acquired per bladder and averaged for analysis. Nerve density was quantified using Image J as described ( Turco et al, 2019 ). Briefly, within Image J, the entire stroma or muscle was outlined and saved in the region of interest manager tool within Image J for analysis.…”

A mechanism linking perinatal 2,3,7,8 tetrachlorodibenzo-p-dioxin exposure to lower urinary tract dysfunction in adulthood

“…3 A). We focused specifically on the periductal region, as it contains most of the prostate periductal smooth muscle ( Turco et al, 2019 ). In utero and lactational TCDD significantly increased noradrenergic axon density in the dorsal prostate, suggesting that TCDD modifies axon patterning during organ development ( Fig.…”

“…Exposure of the fetus to TCDD during the period when noradrenergic axons are recruited into the prostate (Turco et al, 2019) increases abundance of Artn, a neurotrophic factor driving noradrenergic axon guidance and growth. ARTN mediates sympathetic axon growth along vasculature at the time of initial axon extension, induces sympathetic axon outgrowth in vitro, and attracts sympathetic axons in vitro and in vivo (Enomoto et al, 2001;Glebova and Ginty, 2005).…”

“…Paraffin-embedded tissue sections (10 µm) were deparaffinized with xylene and rehydrated in a series of graded concentrations of ethanol. Immunofluorescence staining was conducted as described previously (Abler et al, 2011;Turco et al, 2019) using the antibodies listed in Table S1. Tissue sections were imaged using an SP8 confocal microscope (Leica) fitted with a 20× oil immersion objective (HC PL Apo CS2 NA=0.75; Leica).…”

“…We offer new evidence that the LUTD disease process can be initiated far earlier than previously considered. Using bulk RNA sequencing (RNA-seq) of the fetal prostate, we discovered that TCDD exposure coinciding with the onset of prostate innervation ( Turco et al, 2019 ) increases abundance of the neurotrophic/survival factor artemin ( Artn ), which was previously shown to be critical for noradrenergic axon development ( Baloh et al, 1998 ; Honma et al, 2002 ). TCDD rapidly increases noradrenergic axon density in the fetal prostate.…”