Expression of the G protein-coupled receptor (GPR) 37 and GPR37L1 in the mouse digestive system

Abstract

G protein-coupled receptor (GPR) 37 and GPR37L1 are known to modulate the dopaminergic neuron activity, and recently, they are identified as candidate prosaposin receptors. Intercellular prosaposin is proteolytically processed into four saposins, each of which acts as a sphingolipid hydrolase activator in the lysosome. In contrast, extracellular prosaposin exerts a trophic effect on neurons via GPR37 and GPR37L1. In this study, the expression patterns of GPR37 and GPR37L1 in the mouse digestive system were examined immunohistochemically. The islets of Langerhans of the pancreas showed intense immunoreactivity for GPR37 and GPR37L1. Weak immunoreactivity for GPR37 and GPR37L1 was found in the nerve plexuses of the esophagus and small and large intestines. Colocalization of GPR37 and tyrosine hydroxylase immunoreactivity was observed in the neuron of the nerve plexus of the large intestine. This study suggests the possibility that prosaposin affects the function of islet-secreting cells. Also, the expression of GPR37 and GPR37L1 in the nerve plexus suggests that prosaposin exerts a trophic effect not only in the central nervous system, but also in the enteric nervous system.

Orphan G Protein-Coupled Receptor GPR37 as an Emerging Therapeutic Target

“…By expressing GPR37, REG4 contributes to peritoneal metastasis and establishes a positive feedback loop in gastric cancer. 133 These findings indicate that targeting GPR37 holds promise as a potential therapeutic approach for the development of novel treatments for various types of cancers and their metastasis.…”

Impaired Aversive Memory Formation in GPR37L1KO Mice

“…GPR37L1 is an orphan G-protein-coupled receptor enriched in oligodendrocyte progenitors and astrocytes [1][2][3]. Even though it is predominately expressed in the brain [4], GPR37L1 can be found in the heart and gastrointestinal tract [5][6][7]. GPR37L1 is known for its neuroprotective and glioprotective properties [8].…”

Expression of prosaposin and its G protein-coupled receptor (GPR) 37 in mouse cochlear and vestibular nuclei

“…Finally, the sections were colorized for 10 min in 0.1 M Tris–HCl buffer (pH 7.4) containing 0.02% diaminobenzidine (DAB) and 0.003% H 2 O 2 , and then counterstained with hematoxylin, dehydrated, and coverslipped. The antibody specificities were reported previously [ 33 ]. For immunofluorescence, the sections were incubated with 2% normal donkey serum at RT for 30 min, and then incubated with guinea pig anti-PGP9.5 polyclonal antibody (GTX10410, GeneTex) diluted 1:500 or goat anti-GFAP polyclonal antibody (GTX89226, GeneTex) diluted 1:500, and anti-prosaposin antibody (GTX101064) diluted 1:250 or anti-GPR37 antibody (bs-13534R) diluted 1:250 at 4°C for 48 hr.…”