Differential expression of FABP 3, 5, 7 in infantile and adult monkey cerebellum.

To clarify the involvement of fatty acid binding proteins (FABPs) in cerebellar development and function, we explored the distribution of three brain-expressed FABPs, FABP 3, 5 and 7, by comparing three animal groups--infantile, normal and postischemic adult monkeys. Immunoblotting analysis revealed intense expression of FABP 3 and 7, but not of FABP5, in the control and postischemic adult cerebellum. The protein levels of FABP7, but not of FABP 3 or 5, gradually increased until 2 weeks after the insult.

Expression of fatty acid-binding proteins in adult hippocampal neurogenic niche of postischemic monkeys.

Intracellular fatty acid (FA) chaperones known as FA-binding proteins (FABPs) are a group of molecules known to participate in cellular metabolic processes such as lipid storage, membrane synthesis, and β-oxidation or to coordinate transcriptional programs. However, their role in adult neurogenesis still remains obscure. The FABPs expressed in the central nervous system (CNS) are heart-type (FABP3), epidermal-type (FABP5), and brain-type (FABP7).

Expression of neurotrophin receptors by proliferating glia in postischemic hippocampal CA1 sector of adult monkeys.

Transient global cerebral ischemia elicits a nearly total neuronal cell death in the hippocampal CA1 sector, accompanied by a marked microglial and astroglial proliferation. The molecular mechanisms regulating the postischemic glial reaction in the primate brain remain obscure. Here we present in situ evidence that proliferating postischemic microglia in adult monkey CA1 sector express the neurotrophin receptor TrkA, while activated astrocytes were labeled for the TrkA ligand nerve growth factor (NGF) and the tyrosine kinase TrkB, a receptor for brain-derived neurotrophic factor (BDNF).

Expression of matrix metalloproteinases in the neurogenic niche of the adult monkey hippocampus after ischemia.

Matrix metalloproteinases (MMPs), zinc-dependent endopeptidases capable of remodeling extracellular matrix and regulating cellular signals, have been implicated in various neurological functions and diseases. However, the role of MMPs in the adult neurogenesis still remains to be clarified, particularly in the primate. Here, we studied differential expression of MMP9/2 in the neurogenic niche of the hippocampal dentate gyrus (DG) after transient global brain ischemia in young adult macaque monkeys.

Expression of free fatty acid receptor GPR40 in the neurogenic niche of adult monkey hippocampus.

Polyunsaturated free fatty acids (PUFAs) are known to play critical roles for the development, maintenance, and function of the brain. Recently, we reported that G-protein coupled receptor 40 (GPR40), one type of PUFA receptors, is expressed throughout the adult primate central nervous system including the hippocampus. This opens a possibility that PUFA might act as extracellular signaling molecules at the GPR40 receptor to regulate neuronal function.

Expression of free fatty acid receptor GPR40 in the central nervous system of adult monkeys.

The G-protein coupled receptor 40 (GRP40) is a transmembrane receptor for free fatty acids, and is known for its relation to insulin secretion in the pancreas. Recent studies demonstrated that spatial memory and hippocampal long-term potentiation of rodents and cognitive function of humans are improved by a dietary supplementation with arachidonic and/or docosahexaenoic acids, which are possible ligands for GPR40. While free fatty acid effects on the brain might be related to GPR40 activation, the role of GPR40 in the central nervous system (CNS) is at present not known.