Regulation of neural stem cells by choroid plexus cells population

N-methyl-D-aspartate receptor antibody and the choroid plexus in schizophrenia patients with tardive dyskinesia

BACKGROUND

Immune disturbance has been postulated to be one of the mechanisms underlying the pathogenesis of tardive dyskinesia (TD). Recently, the role of autoimmune abnormality in TD has been increasingly recognized. Autoantibodies against neuronal N-methyl-D-aspartate receptor (NMDAR) may be cross-reactive in the brain in neuropsychiatric disorders, and the choroid plexus (CP) is a crucial immune barrier in the central nervous system (CNS). We supposed that NMDAR antibodies might underlie the pathophysiological process of TD through the mediation of CP.

METHODS

Serum NMDAR antibody levels were assessed by enzyme-linked immunosorbent assay, CP and ventricle volumes were assessed by magnetic resonance imaging in schizophrenia patients with TD (n = 61), without TD (NTD, n = 61), and in healthy controls (n = 74). Psychopathology and TD severity were assessed by the Positive and Negative Syndrome Scale and Abnormal Involuntary Movement Scale (AIMS).

RESULTS

NMDAR antibody levels were significantly higher, CP volumes were larger in the TD group than in the NTD group (p = 0.022; p = 0.019, respectively). In the TD group, higher NMDAR antibody level was correlated with larger CP volume (β = 0.406, p = 0.002). An elevated NMDAR antibody level and enlarged CP volume were correlated with orofacial AIMS score (β = 0.331, p = 0.011; β = 0.459, p = 3.34 × 10^-4, respectively). In a mediation model, the effect of NMDAR antibody level on the orofacial AIMS score was mediated by the CP volume (indirect effect: β = 0.08, 95% confidence interval = 0.002-0.225; direct effect: β = 0.14, p = 0.154).

CONCLUSIONS

Our findings highlight a potential NMDAR antibody-associated mechanism in orofacial TD, which may be mediated by increased CP volume.

Mechanism of the neuroprotective effect of injecting brain cells on ST36 in an animal model of Parkinson's disease

In Parkinson's disease, the dopaminergic neurons of the brain are destroyed. Dopamine is an important neurotransmitter that acts on the basal ganglia of the brain, allowing precise body movement. In the early stages of Parkinson's disease, levodopa appears to alleviate clinical symptoms; however, during long-term use, motor complications occur. There is no clear treatment or remedy for Parkinson's disease; therefore, the development of novel therapies is urgently required. In the present study, mouse choroid plexus cells were transplanted into ST36 in a mouse model of Parkinson's disease to determine whether the motor function could be restored. Pole tests showed changes in motor dysfunction in the mice. The athletic ability of the mice was significantly lowered after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) injection and significantly increased after choroidal neuron cell treatment. Injection of di-alkyl indocarbocyanine (DiI) (as a trace substance) confirmed that the choroid plexus cells injected into acupuncture point ST36 were transferred to the brain. In the Parkinson's disease model, choroid plexus cell injection into ST36 inhibited the decrease in tyrosine hydroxylase (TH) expression and decreased the activation of inflammatory factors mitochondrial cytochrome C oxidase (COX2) and inducible NO synthase (iNOS). Apoptosis factors Cytochrome C and BCL2 associated X, apoptosis regulator (BAX) levels were decreased and B-Cell CLL/Lymphoma 2 (BCL2) levels were increased. Taken together, these results suggest that the injection of choroid plexus cell at ST36 had neuroprotective effects in the Parkinson's disease mouse model. The results suggest new possibilities for the treatment of Parkinson's disease.

Association of Choroid Plexus Enlargement With Cognitive, Inflammatory, and Structural Phenotypes Across the Psychosis Spectrum

OBJECTIVE

The choroid plexus is an important physiological barrier and produces CSF and neurotrophic, angiogenic, and inflammatory factors involved in brain development. Choroid plexus abnormalities have been implicated in both schizophrenia and bipolar disorder. A previous choroid plexus transcriptomic analysis of schizophrenia identified an upregulation of immune and inflammatory genes that correlated with peripheral inflammatory markers. The purpose of this study was to examine choroid plexus volume in probands across the psychosis spectrum and in their first-degree and axis II cluster A relatives, as well as choroid plexus familiality and choroid plexus covariance with clinical, cognitive, brain, and peripheral marker measures.

METHODS

Choroid plexus volume was quantified (using FreeSurfer) in psychosis probands, their first-degree and axis II cluster A relatives, and healthy control subjects, organized by DSM-IV-TR diagnosis. Analyte, structural connectivity, and genotype data were collected from a subset of study subjects.

RESULTS

Choroid plexus volume was significantly larger in probands compared with first-degree relatives or healthy control subjects; first-degree relatives had intermediate enlargement compared with healthy control subjects; and total choroid plexus volume was significantly heritable. Larger volume was associated with worse cognition, smaller total gray matter and amygdala volume, larger lateral ventricle volume, and lower structural connectivity in probands. Associations between larger volume and higher levels of interleukin 6 in probands was also observed.

CONCLUSIONS

These findings suggest the involvement of the choroid plexus across the psychosis spectrum with a potential pathophysiological mechanism involving the neuroimmune axis, which functions in maintaining brain homeostasis and interacting with the peripheral immune and inflammatory system. The choroid plexus may be an important target in future research.

Stromal cells/telocytes and endothelial progenitors in the perivascular niches of the trigeminal ganglion

Stromal cells/telocytes (SCs/TCs) were recently described in the human adult trigeminal ganglion (TG). As some markers are equally expressed in SCs/TCs and endothelial cells, we hypothesized that a subset of the TG SCs/TCs is in fact represented by endothelial progenitor cells of a myelomonocytic origin. This study aimed to evaluate whether the interstitial cells of the human adult TG correlate with the myelomonocytic lineage. We used primary antibodies for c-erbB2/HER-2, CD31, nestin, CD10, CD117/c-kit, von Willebrand factor (vWF), CD34, Stro-1, CD146, α-smooth muscle actin (α-SMA), CD68, VEGFR-2 and cytokeratin 7 (CK7). The TG pial mesothelium and subpial vascular microstroma expressed c-erbB2/HER-2, CK7 and VEGFR-2. SCs/TCs neighbouring the neuronoglial units (NGUs) also expressed HER-2, which suggests a pial origin. These cells were also positive for CD10, CD31, CD34, CD68 and nestin. Endothelial cells expressed CD10, CD31, CD34, CD146, nestin and vWF. We also found vasculogenic networks with spindle-shaped and stellate endothelial progenitors expressing CD10, CD31, CD34, CD68, CD146 and VEGFR-2. Isolated mesenchymal stromal cells expressed Stro-1, CD146, CK7, c-kit and nestin. Pericytes expressed α-SMA and CD146. Using transmission electron microscopy (TEM), we found endothelial-specific Weibel-Palade bodies in spindle-shaped stromal progenitors. Our study supports the hypothesis that an intrinsic vasculogenic niche potentially involved in microvascular maintenance and repair might be present in the human adult trigeminal ganglion and that it might be supplied by either the pial mesothelium or the bone marrow niche.

Cerebrospinal fluid-stem cell interactions may pave the path for cell-based therapy in neurological diseases

Recent studies have suggested that the regulation of endogenous neural stem cells (NSCs) or transplanting of exogenous nerve cells are the newest and most promising methods for the treatment of dementia and other neurological diseases. The special location and limited number of endogenous NSCs, however, restrict their clinical application. The success in directional differentiation of exogenous stem cells from other tissue sources into neural cells has provided a novel source for NSCs. Study on the relative mechanisms is still at the preliminary stage. Currently the induction methods include: 1) cell growth factor induction; 2) chemical induction; 3) combined growth factor-chemical induction; or 4) other induction methods such as traumatic brain tissue homogenate, gene transfection, traditional Chinese medicine, and coculture induction. Cerebrospinal fluid (CSF), as a natural medium under physiological conditions, contains a variety of progrowth peptide factors that can promote the proliferation and differentiation of mesenchymal stromal cells (MSCs) into neural cells through the corresponding receptors on the cell surface. This suggests that CSF can not only nourish the nerve cells, but also become an effective and suitable inducer to increase the yield of NSCs. However, some other studies believed that CSF contained certain inhibitory components against the differentiation of primary stem cells into mature neural cells. Based on the above background, here we review the relative literature on the influence of the CSF on stem cells in order to provide a more comprehensive reference for the wide clinical application of NSCs in the future.