Background: Latent chronic inflammation has been proposed as a key mediator of multiple derangements in metabolic syndrome (MetS), which are increasingly becoming recognized as risk factors for age-related cognitive decline. However, the question remains whether latent chronic inflammation indeed induces brain inflammation and cognitive decline.
Methods: A mouse model of latent chronic inflammation was constructed by a chronic subcutaneous infusion of low dose lipopolysaccharide (LPS) for four weeks.
Morphologically dynamic dendritic spines are the major sites of neuronal plasticity in the brain; however, the molecular mechanisms underlying their morphological dynamics have not been fully elucidated. Phldb2 is a protein that contains two predicted coiled-coil domains and the pleckstrin homology domain, whose binding is highly sensitive to PIP. We have previously demonstrated that Phldb2 regulates synaptic plasticity, glutamate receptor trafficking, and PSD-95 turnover.
View Article and Find Full Text PDFInterleukin-18 (IL18) is an inflammatory cytokine that is related to psychiatric disorders such as depression and cognitive impairment. We previously found that IL18 deficiency may cause hippocampal impairment, resulting in depression-like behavioral changes. However, the potential role of IL18 in stressful conditions remains uncertain.
View Article and Find Full Text PDFStem cell therapy is used to restore neurological function in stroke patients. We have previously reported that ischemia-induced multipotent stem cells (iSCs), which are likely derived from brain pericytes, develop in poststroke human and mouse brains. Although we have demonstrated that iSCs can differentiate into neural lineage cells, the factors responsible for inducing this differentiation remain unclear.
View Article and Find Full Text PDFNerves in the renal parenchyma comprise sympathetic nerves that act on renal arteries and tubules to decrease blood flow and increase primary urine reabsorption, respectively. Synaptic vesicles release neurotransmitters that activate their effector tissues. However, the mechanisms by which neurotransmitters exert individual responses to renal effector cells remain unknown.
View Article and Find Full Text PDFInterleukin-18 (IL-18) is an inflammatory cytokine that has been linked to energy homeostasis and psychiatric symptoms such as depression and cognitive impairment. We previously revealed that deficiency in IL-18 led to hippocampal abnormalities and resulted in depression-like symptoms. However, the impact of IL-18 deficiency on other brain regions remains to be clarified.
View Article and Find Full Text PDFCoordination of skilled movements and motor planning relies on the formation of regionally restricted brain circuits that connect cortex with subcortical areas during embryonic development. Layer 5 neurons that are distributed across most cortical areas innervate the pontine nuclei (basilar pons) by protrusion and extension of collateral branches interstitially along their corticospinal extending axons. Pons-derived chemotropic cues are known to attract extending axons, but molecules that regulate collateral extension to create regionally segregated targeting patterns have not been identified.
View Article and Find Full Text PDFVibration is detected by mechanoreceptors, including Pacinian corpuscles (PCs), which are widely distributed in the human body including the adventitia of large blood vessels. Although the distribution of PCs around large limb vessels has been previously reported, there remains no consensus on their distribution in the adventitia of the human deep blood vessels in the upper arm. In addition, the physiological functions of PCs located around the deep limb blood vessels remain largely unknown.
View Article and Find Full Text PDFInterleukin-18 (IL-18) is an inflammatory cytokine linked to major depressive disorder (MDD). MDD is closely related to metabolic disorders, such as diabetes mellitus (DM) and obesity. Moreover, DM is associated with cognitive impairment and promotes apoptosis of hippocampal cells by activating pro-apoptotic and inhibiting anti-apoptotic factors.
View Article and Find Full Text PDFThe essential involvement of phosphoinositides in synaptic plasticity is well-established, but incomplete knowledge of the downstream molecular entities prevents us from understanding their signalling cascades completely. Here, we determined that Phldb2, of which pleckstrin-homology domain is highly sensitive to PIP, functions as a phosphoinositide-signalling mediator for synaptic plasticity. BDNF application caused Phldb2 recruitment toward postsynaptic membrane in dendritic spines, whereas PI3K inhibition resulted in its reduced accumulation.
View Article and Find Full Text PDFBiochem Biophys Res Commun
March 2019
Transcription of the platelet-derived growth factor receptor α (PDGFRA/Pdgfra) gene is considered to be precisely regulated. We have previously reported that the PDGFRA/Pdgfra gene is regulated by a dual promoter system in human and mouse, in which a novel PDGFRA/Pdgfra transcript has a first exon (exon 1β) different from that of the canonical PDGFRA/Pdgfra transcript (exon 1α). To elucidate the function of each transcript, we first investigated the contribution of different PDGFRA transcripts to final protein levels.
View Article and Find Full Text PDFPacinian corpuscles are vibration-sensing mechanoreceptors that are densely distributed in the dermis of the human hand. Although they are also known to occur in various other regions/structures throughout the human body, including the adventitia of large vessels, their precise distribution and function in arteries remain unclear. In the present study, we identified Pacini-like lamellar corpuscles (LCs) adjacent to the femoral artery, and investigated their distribution with respect to that structure via a histological analysis.
View Article and Find Full Text PDFAMPK is a widely expressed intracellular energy sensor that monitors and modulates energy expenditure. Transient receptor potential ankyrin 1 (TRPA1) channel is a widely recognized chemical and thermal sensor that plays vital roles in pain transduction. In this study, we discovered a functional link between AMPK and TRPA1 in dorsal root ganglion (DRG) neurons, in which AMPK activation rapidly resulted in downregulation of membrane-associated TRPA1 and its channel activity within minutes.
View Article and Find Full Text PDFThe renal nerve plexus comprises efferent and afferent fibers. It controls urine production and bodily fluid homeostasis. Efferent fibers to the kidney include sympathetic nerve fibers from their main ganglia, the prevertebral suprarenal ganglia (SrG), and the paravertebral sympathetic chain ganglia (ChG).
View Article and Find Full Text PDFA network of myelinated nerve fibers in the peritoneum covers the abdominal wall. We studied the topographic distribution of this network, explored the fibers' destination in the central nervous system, and examined the markers in these fibers in order to identify the nature of the sensation conveyed by the network of nerve fibers in rats. We used Sihler's method, which stains myelinated fibers in whole mount materials, and observed a dense nerve network and endings toward the peritoneal cavity in the peritoneum that covers the abdomen's lateral bulge.
View Article and Find Full Text PDFInterleukin-18 (IL-18) is a pro-inflammatory cytokine and an important mediator of peripheral inflammation and host immune response. IL-18 functions through its binding with the IL-18 receptor (IL-18R), which consists of two chains, an IL-18-binding α chain (IL-18Rα) and a signaling β chain. IL-18 and IL-18R are expressed in the brain; however, limited information is available on IL-18R expression and the role of IL-18 in neurosecretory cells.
View Article and Find Full Text PDFThe neuronal spine is a small, actin-rich dendritic or somatic protrusion that serves as the postsynaptic compartment of the excitatory synapse. The morphology of the spine reflects the activity of the synapse and is regulated by the dynamics of the actin cytoskeleton inside, which is controlled by actin binding proteins such as non-muscle myosin. Previously, we demonstrated that the subcellular localization and function of myosin IIb are regulated by its binding partner, filamin-A interacting protein (FILIP).
View Article and Find Full Text PDFInterleukin-18 (IL-18), which is involved in the inflammatory response, is also found in the cerebral cortex. IL-18 receptor-immunoreactive (IL-18R-ir) neurons are present in layer V of the retrosplenial cortex (RSC). In the adult IL-18 knock out (KO) mice, no IL-18R-ir neurons but many degenerated neurons are present in layer V of the RSC, suggesting that any changes in the neurons of layer V have occurred during postnatal development.
View Article and Find Full Text PDFInterleukin 18 (IL-18) participates in the inflammatory immune response of lymphocytes. Delay in learning or memory are common in the IL-18 knockout mouse. Many IL-18-immunoreactive neurons are found in the retrosplenial cortex (RSC) and the subiculum.
View Article and Find Full Text PDFPeripheral nerve injury induces proliferation of microglia in the spinal cord, which can contribute to neuropathic pain conditions. However, candidate molecules for proliferation of spinal microglia after injury in rats remain unclear. We focused on the colony-stimulating factors (CSFs) and interleukin-34 (IL-34) that are involved in the proliferation of the mononuclear phagocyte lineage.
View Article and Find Full Text PDFBackground: Microglia are the resident macrophage population of the central nervous system (CNS) and play essential roles, particularly in inflammation-mediated pathological conditions such as ischemic stroke. Increasing evidence shows that the population of vascular cells located around the blood vessels, rather than circulating cells, harbor stem cells and that these resident vascular stem cells (VSCs) are the likely source of some microglia. However, the precise traits and origins of these cells under pathological CNS conditions remain unclear.
View Article and Find Full Text PDFThe callosal connections between the two hemispheres of the neocortex are altered in certain psychiatric disorders including schizophrenia. However, how and why the callosal connection is impaired in patients suffering from psychiatric diseases remain unclear. Filamin A interacting protein (FILIP), whose alteration through mutation relates to schizophrenic pathogenesis, binds to actin-binding proteins and controls neurotransmission.
View Article and Find Full Text PDFBackground: Artemin, a member of the glial cell line-derived neurotrophic factor family, is known to have a variety of neuronal functions, and has been the subject of attention because it has interesting effects, including bi-directional results in modulation in neuropathic and inflammatory pain. It has been shown that the overexpression of artemin is associated with an increase in the expression of TRP family channels in primary afferents and subsequent hyperalgesia, and an increase in neuronal activity. The purpose of this study was to examine the peripheral synthesis of artemin in inflammatory and neuropathic pain models, and to demonstrate the effects of long-term or repeated application of artemin in vivo on pain behaviors and on the expression of TRP family channels.
View Article and Find Full Text PDFCell positioning and neuronal network formation are crucial for proper brain function. Disrupted-in-Schizophrenia 1 (DISC1) is anterogradely transported to the neurite tips, together with Lis1, and functions in neurite extension via suppression of GSK3β activity. Then, transported Lis1 is retrogradely transported and functions in cell migration.
View Article and Find Full Text PDFLearning and memory depend on morphological and functional changes to neural spines. Non-muscle myosin 2b regulates actin dynamics downstream of long-term potentiation induction. However, the mechanism by which myosin 2b is regulated in the spine has not been fully elucidated.
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