Effect of chemokine CC ligand 2 (CCL2) on α‑synuclein‑induced microglia proliferation and neuronal apoptosis

The Function of NF-Kappa B During Epilepsy, a Potential Therapeutic Target

The transcriptional regulator nuclear factor kappa B (NF-κB) modulates cellular biological activity by binding to promoter regions in the nucleus and transcribing various protein-coding genes. The NF-κB pathway plays a major role in the expressing genes related to inflammation, including chemokines, interleukins, and tumor necrosis factor. It also transcribes genes that can promote neuronal survival or apoptosis. Epilepsy is one of the most common brain disorders and it not only causes death worldwide but also affects the day-to-day life of affected individuals. While epilepsy has diverse treatment options, there remain patients who are not sensitive to the existing treatment methods. Recent studies have implicated the critical role of NF-κB in epilepsy. It is upregulated in neurons, glial cells, and endothelial cells, due to neuronal loss, glial cell proliferation, blood-brain barrier dysfunction, and hippocampal sclerosis through the glutamate and γ-aminobutyric acid imbalance, ion concentration changes, and other mechanisms. In this review, we summarize the functional changes caused by the upregulation of NF-κB in the central nervous system during different periods after seizures. This review is the first to deconvolute the complicated functions of NF-κB, and speculate that the regulation of NF-κB can be a safe and effective treatment strategy for epilepsy.

Efficacy of Human Umbilical Cord Blood-Mononuclear Cell Transplantation for MSA Treatment and Its Effects on Changes in T-Cell Subsets in Peripheral Blood and Inflammatory Factors

Objective

This study is aimed at examining the efficacy of human umbilical cord blood-mononuclear cell (hUCB-MNCs) transplantation through lateral atlanto-occipital space puncture in multiple system atrophy (MSA) treatment and investigating changes in T-cell subsets in peripheral blood and inflammatory factors in patients before and after treatment.

Methods

A total of 20 patients with MSA who underwent hUCB-MNC transplantation through lateral atlanto-occipital space puncture in the Liaocheng People's Hospital were enrolled. Patients were followed up at 0, 1, 3, and 6 months after treatment, and the Unified Multiple System Atrophy Rating Scale (UMSARS) scores, TNF-α in the peripheral blood, IL-6, percentage of CD4, and CD4/CD8 ratio were evaluated and compared for each follow-up point; any adverse effects were recorded.

Results

UMSARS Part I scores were 20.55 ± 3.80, 19.20 ± 3.78, and 19.40 ± 4.11, 1, 3, and 6 months, respectively, after treatment and were significantly lower as compared to that before treatment (23.50 ± 4.72; P < 0.05). Similarly, UMSARS Part II scores 1, 3, and 6 months after treatment were 25.50 ± 5.01, 24.05 ± 5.01, and 24.25 ± 5.05, respectively, significantly lower as compared to that before treatment (30.15 ± 5.63; P < 0.05). The IL-6 values in the peripheral blood 1, 3, and 6 months after treatment were 5.25 ± 2.70 pg/m, 2.96 ± 1.75 pg/m, and 3.31 ± 1.62 pg/m, respectively, which were significantly lower (P < 0.05) than that before treatment (8.22 ± 4.69) pg/m. The TNF-α levels at 3 and 6 months after treatment were 13.08 ± 6.13 pg/m and 12.24 ± 4.76 pg/m, respectively, which were significantly lower than that before treatment (22.99 ± 13.30; P < 0.01). The CD4/CD8 ratios in the peripheral blood 1, 3, and 6 months after treatment were 1.09 ± 0.25, 1.30 ± 0.24, and 1.43 ± 0.22, respectively, which were significantly different than that before treatment (0.81 ± 0.24, P < 0.01). Similarly, the CD4 percentages 1, 3, and 6 months after treatment were 34.09 ± 1.79, 36.05 ± 1.50, and 36.47 ± 1.47, respectively, which were significantly different than that before treatment (0.81 ± 0.24; P < 0.01).

Conclusion

hUCB-MNC transplantation through lateral atlanto-occipital space puncture could significantly improve the symptoms and signs in patients with MSA and delay the disease progression. Thus, hUCB-MNCs may modulate immune activity and reduce the inflammatory response.

Microglia induce neurogenic protein expression in primary cortical cells by stimulating PI3K/AKT intracellular signaling in vitro

Emerging evidence suggests that microglia can support neurogenesis. Little is known about the mechanisms by which microglia regulate the cortical environment and stimulate cortical neurogenesis. We used an in vitro co-culture model system to investigate the hypothesis that microglia respond to soluble signals from cortical cells, particularly following mechanical injury, to alter the cortical environment and promote cortical cell proliferation, differentiation, and survival. Analyses of cortical cell proliferation, cell death, neurogenic protein expression, and intracellular signaling were performed on uninjured and injured cortical cells in co-culture with microglial cell lines. Microglia soluble cues enhanced cortical cell viability and proliferation cortical cells. Co-culture of injured cortical cells with microglia significantly reduced cell death of cortical cells. Microglial co-culture significantly increased Nestin + and α-internexin + cortical cells. Multiplex ELISA and RT-PCR showed decreased pro-inflammatory cytokine production by microglia co-cultured with injured cortical cells. Inhibition of AKT phosphorylation in cortical cells blocked microglial-enhanced cortical cell viability and expression of neurogenic markers in vitro. This in vitro model system allows for assessment of the effect of microglial-derived soluble signals on cortical cell viability, proliferation, and stages of differentiation during homeostasis or following mechanical injury. These data suggest that microglia cells can downregulate inflammatory cytokine production following activation by mechanical injury to enhance proliferation of new cells capable of neurogenesis via activation of AKT intracellular signaling. Increasing our understanding of the mechanisms that drive microglial-enhanced cortical neurogenesis during homeostasis and following injury in vitro will provide useful information for future primary cell and in vivo studies.

CCL2/CCR2 Chemokine System in Embryonic Hypothalamus: Involvement in Sexually Dimorphic Stimulatory Effects of Prenatal Ethanol Exposure on Peptide-Expressing Neurons

Maternal consumption of ethanol during pregnancy is known to increase the offspring's risk for developing alcohol use disorders and associated behavioral disturbances. Studies in adolescent and adult animals suggest the involvement of neuroimmune and neurochemical systems in the brain that control these behaviors. To understand the origin of these effects during early developmental stages, we examined in the embryo and neonate the effects of maternal intraoral administration of ethanol (2 g/kg/day) from embryonic day 10 (E10) to E15 on the inflammatory chemokine C-C motif ligand 2 (CCL2) and its receptor CCR2 in a specific, dense population of neurons in the lateral hypothalamus (LH), where they are closely related to an orexigenic neuropeptide, melanin-concentrating hormone (MCH), known to promote ethanol consumption and related behaviors. We found that prenatal ethanol exposure increases the expression and density of CCL2 and CCR2 cells along with MCH neurons in the LH and the colocalization of CCL2 with MCH. We also discovered that these effects are sexually dimorphic, consistently stronger in female embryos, and are blocked by maternal administration of a CCL2 antibody (1 and 5 µg/day, i.p., E10-E15) that neutralizes endogenous CCL2 and of a CCR2 antagonist INCB3344 (1 mg/day, i.p., E10-E15) that blocks CCL2's main receptor. These results, which in the embryo anatomically and functionally link the CCL2/CCR2 system to MCH neurons in the LH, suggest an important role for this neuroimmune system in mediating ethanol's sexually dimorphic, stimulatory effect on MCH neurons that may promote higher level of alcohol consumption described in females.

Critical Role of Monocyte Recruitment in Optic Nerve Damage Induced by Experimental Optic Neuritis

Neuroinflammatory diseases are characterized by blood-brain barrier disruption (BBB) and leukocyte infiltration. We investigated the involvement of monocyte recruitment in visual pathway damage provoked by primary optic neuritis (ON) induced by a microinjection of bacterial lipopolysaccharide (LPS) into the optic nerve from male Wistar rats. Increased Evans blue extravasation and cellularity were observed at 6 h post-LPS injection. In WT-GFPþ/WT chimeric rat optic nerves, the presence of GFP(+) neutrophils and GFP(+) monocytes, and in wild-type rat optic nerves, an increase in CD11b⁺CD45^low and CD11b⁺CD45^high cell number, were observed at 24 h post-LPS. Gamma-irradiation did not affect the increase in BBB permeability, but significantly lessened the decrease in pupil light reflex (PLR), and retinal ganglion cell (RGC) number induced by LPS. At 6 h post-LPS, an increase in chemokine (C-C motif) ligand 2 (CCL2) immunoreactivity co-localized with neutrophils (but not microglia/macrophages or astrocytes) was observed, while at 24 h post-injection, an increase in Iba-1-immunoreactivity and its co-localization with CCL2 became evident. The co-injection of LPS with bindarit (a CCL2 synthesis inhibitor) lessened the effect of LPS on PLR, and RGC loss. The treatment with etoposide or gadolinium chloride that significantly decreased peripheral monocyte (but not neutrophil or lymphocyte) percentage decreased the effect of LPS on PLR, and RGC number. Moreover, a negative correlation between PRL and monocyte (but not lymphocyte or neutrophil) percentage was observed at 7 days post-LPS. Taken together, these results support that monocytes are key players in the initial events that take place during primary ON.