Exosomes derived from human umbilical cord mesenchymal stem cells alleviate Parkinson's disease and neuronal damage through inhibition of microglia

Microglia-mediated inflammatory responses have been shown to play a crucial role in Parkinson's disease. In addition, exosomes derived from mesenchymal stem cells have shown anti-inflammatory effects in the treatment of a variety of diseases. However, whether they can protect neurons in Parkinson's disease by inhibiting microglia-mediated inflammatory responses is not yet known. In this study, exosomes were isolated from human umbilical cord mesenchymal stem cells and injected into a 6-hydroxydopamine-induced rat model of Parkinson's disease. We found that the exosomes injected through the tail vein and lateral ventricle were absorbed by dopaminergic neurons and microglia on the affected side of the brain, where they repaired nigral-striatal dopamine system damage and inhibited microglial activation. Furthermore, in an in vitro cell model, pretreating lipopolysaccharide-stimulated BV2 cells with exosomes reduced interleukin-1β and interleukin-18 secretion, prevented the adoption of pyroptosis-associated morphology by BV2 cells, and increased the survival rate of SH-SY5Y cells. Potential targets for treatment with human umbilical cord mesenchymal stem cells and exosomes were further identified by high-throughput microRNA sequencing and protein spectrum sequencing. Our findings suggest that human umbilical cord mesenchymal stem cells and exosomes are a potential treatment for Parkinson's disease, and that their neuroprotective effects may be mediated by inhibition of excessive microglial proliferation.

Active compounds of herbs ameliorate impaired cognition in APP/PS1 mouse model of Alzheimer's disease

Alzheimer's disease (AD), the most common cause of dementia, is a neurodegenerative disorder characterized by amyloid plaque accumulations, intracellular tangles and neuronal loss in certain brain regions. It has been shown that a disturbance of normal iron metabolism contributes to the pathophysiology of AD. However, the mechanism underlying abnormal iron load in the brain of AD patients is unclear. The frontal cortex, an important brain structure for executive function, is one of the regions affected by AD. We investigated the beneficial effects of active compounds of Epimedium, Astragaoside and Puerarin on iron metabolism in the frontal cortex of six-month-old APPswe/PS1_ΔE9 (APP/PS1) double transgenic mouse, a model of AD. Treatment with the active compounds reduced cognitive and memory deficits and damaged cell ultrastructure in APP/PS1 mice. These beneficial effects were associated with changes in expression levels of iron metabolism proteins in the frontal cortex, including divalent metal transporter with iron response element (DMT1-with IRE), divalent metal transporter without iron response element (DMT1-without IRE), transferrin (TF) and transferring receptor 1 (TfR1); three release proteins including the exporter ferroportin 1 (Fpn1), ceruloplasmin (CP) and hephaestin (HEPH), one increased storage iron protein ferritin and one iron regulating hormone hepcidin. These findings suggest that the active compounds improve cognition and memory in brain neurodegenerative disorders and these beneficial effects are associated with reduced impairment of iron metabolism. This study may provide a new strategy for developing novel drugs to treat AD.

Compound of icariin, astragalus, and puerarin mitigates iron overload in the cerebral cortex of Alzheimer's disease mice

Increasing evidence indicates that disruption of normal iron homeostasis may contribute to pathological development of Alzheimer's disease. Icariin, astragalus, and puerarin have been shown to suppress iron overload in the cerebral cortex and improve spatial learning and memory disorders in Alzheimer's disease mice, although the underlying mechanism remains unclear. In the present study, APPswe/PS1ΔE9 transgenic mice were administered icariin, astragalus, and puerarin (120, 80, and 80 mg/kg, respectively, once a day, for 3 months). Iron levels were detected by flame atomic absorption spectroscopy. Interleukin-1β, interleukin-6, and tumor necrosis factor-α levels were measured in the cerebral cortex by enzyme linked immunosorbent assay. Glutathione peroxidase and superoxide dismutase activity and malondialdehyde content were determined by colorimetry. Our results demonstrate that after treatment, iron levels and malondialdehyde content are decreased, while glutathione peroxidase and superoxide dismutase activities are increased. Further, interleukin-1β, interleukin-6, and tumor necrosis factor-α levels were reduced. These results confirm that compounds of icariin, astragalus, and puerarin may alleviate iron overload by reducing oxidative stress and the inflammatory response.

Effective components of Chinese herbs reduce central nervous system function decline induced by iron overload

Abnormally increased levels of iron in the brain trigger cascade amplification in Alzheimer’s disease patients, resulting in neuronal death. This study investigated whether components extracted from the Chinese herbs epimedium herb, milkvetch root and kudzuvine root could relieve the abnormal expression of iron metabolism-related protein in Alzheimer’s disease patients. An APP_swe/PS1_ΔE9 double transgenic mouse model of Alzheimer’s disease was used. The intragastric administration of compounds from epimedium herb, milkvetch root and kudzuvine root improved pathological alterations such as neuronal edema, increased the number of neurons, downregulated divalent metal transporter 1 expression, upregulated ferroportin 1 expression, and inhibited iron overload in the cerebral cortex of mice with Alzheimer’s disease. These compounds reduced iron overload-induced impairment of the central nervous system, indicating a new strategy for developing novel drugs for the treatment of Alzheimer’s disease.

Neuroprotective effect of the active components of three Chinese herbs on brain iron load in a mouse model of Alzheimer's disease

Alzheimer’s disease (AD) is a neurodegenerative brain disorder and the most common cause of dementia. New treatments for AD are required due to its increasing prevalence in aging populations. The present study evaluated the effects of the active components of Epimedium, Astragalus and Radix Puerariae on learning and memory impairment, β-amyloid (Aβ) reduction and brain iron load in an APP_swe/PS1_ΔE9 transgenic mouse model of AD. Increasing evidence indicates that a disturbance of normal iron homeostasis may contribute to the pathology of AD. However, the underlying mechanisms resulting in abnormal iron load in the AD brain remain unclear. It has been hypothesized that the brain iron load is influenced by the deregulation of certain proteins associated with brain iron metabolism, including divalent metal transporter 1 (DMT1) and ferroportin 1 (FPN1). The present study investigated the effects of the active components of Epimedium, Astragalus and Radix Puerariae on the expression levels of DMT1 and FPN1. The treatment with the active components reduced cognitive deficits, inhibited Aβ plaque accumulation, reversed Aβ burden and reduced the brain iron load in AD model mice. A significant increase was observed in the levels of DMT1-iron-responsive element (IRE) and DMT1-nonIRE in the hippocampus of the AD mouse brain, which was reduced by treatment with the active components. In addition, the levels of FPN1 were significantly reduced in the hippocampus of the AD mouse brain compared with those of control mice, and these levels were increased following treatment with the active components. Thus, the present study indicated that the active components of Epimedium, Astragalus and Radix Puerariae may exert a neuroprotective effect against AD by reducing iron overload in the AD brain and may provide a novel approach for the development of drugs for the treatment of AD.

Effect of Tα1 on ESCC RNA-transfected human cord blood dendritic cells induced antitumor activity of cytotoxic T lymphocytes

AIM: To investigate effect of human cord blood dendritic cells (DCs) transfected with RNA of esophageal carcinoma cells on the proliferation of T lymphocyte and on the antitumor activity of cytotoxic T lymphocytes (CTL), and immunoa-djuvant effect of Tα1 on human cord blood dendritic cells.

METHODS: The RNA of T.Tn cells were prepared by TRIzol reagent. The cord blood monocytes were cultured to produce DCs with rhSCF, rhGM-CSF and rhlL-4. The DCs were collected and transfected with tumor cell total RNA. Tα1 was added in culture system to enhance the DCs vaccine. MHC-I, MHC-II and co-stimulatory molecules, CD54, CD80 and CD86 on the surface of DCs were analyzed by FCM. The mixed lymphocyte reaction (MLR) and cytotoxicity of CTLs to T.Tn cells was assayed using MTT colorimetry.

RESULTS: Compared with pre-transfection group, expressions of MHC-I, MHC-II, CD54, CD80 and CD86 (MHC-I: 70.36 ± 6.09vs 8.17 ± 1.93; MHC-II: 72.03 ± 5.32 vs 7.64 ± 5.33; CD54: 69.36 ± 7.33 vs 2.05 ± 2.03; CD80: 67.21 ± 6.77 vs 2.33 ± 1.65; CD86: 68.85 ± 7.41 vs 6.73 ± 1.97, P < 0.01) were significantly higher in DCs transfected with RNA of esophageal carcinoma cells; T cell proliferation was markedly enhanced (10 : 1: 4.77 ± 0.79 vs 1.65 ± 0.71; 50 : 1: 3.85 ± 0.57 vs 1.56 ± 0.13; 100 : 1: 2.89 ± 0.59 vs 1.19 ± 0.21, P < 0.05); and tumor cytolytic activities of cytotoxic T lymphocyte were effectively induced (10 : 1: 27.36 ± 8.93 vs 10.35 ± 2.93; 20 : 1: 44.55 ± 2.36 vs 11.77 ± 1.03; 50 : 1: 51.08 ± 4.92 vs 12.75 ± 1.49, P < 0.05). Tα1 enhanced significantly the surface molecule expression (MHC-I: 87.88 ± 9.13 vs 70.36 ± 6.09; MHC-II: 93.16 ± 3.34 vs 72.03 ± 5.32; CD54: 91.75 ± 3.84 vs 69.36 ± 7.33; CD80: 87.27 ± 8.68 vs 67.21 ± 6.77; CD86: 89.09 ± 6.86 vs 68.85 ± 7.41, P < 0.05), stimulation of proliferation (10 : 1: 8.31 ± 1.78 vs 4.77 ± 0.79; 50 : 1: 5.97 ± 0.14 vs 3.85 ± 0.57; 100 : 1: 4.03 ± 0.13vs 2.89 ± 0.59, P < 0.05) and activity of cytotoxic T lymphocytes (10 : 1: 47.66 ± 4.12 vs 27.36 ± 8.93; 20 : 1: 56.72 ± 7.24 vs44.55 ± 2.36; 50 : 1: 76.48 ± 3.47 vs 51.08 ± 4.92, P < 0.05).

CONCLUSION: DCs from human cord blood monocytes exhibit high expression of MHC and co-stimulatory molecules and enhances T lymphocyte capability after transfection with RNA of esophageal carcinoma. The vaccine of cord blood DCs with adjuvant of Tα1 may provide an effective and specific way for immunotherapy of esophageal carcinoma.

[Effect of yiqi jianpi drugs on apoptosis and relevant gene expression in cultured vascular smooth muscle cell]

OBJECTIVE

To explore the effect of Yiqi Jianpi (YQJP, supplementing Qi and invigorating Spleen) recipe on vascular smooth muscle cells (VSMC) apoptosis and it's mechanisms.

METHODS

VSMC apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nicked labeling (TUNEL) analysis, transmission electron microscope (TEM), flow cytometry and DNA agarose electrophoresis. The expression activity of bcl-2, c-myc and p53 genes were determined using Northern blotting.

RESULTS

The typical characteristics of apoptotic VSMC was observed following treatment by the YQJP drug serum. The DNA extracted from VSMC revealed a ladder pattern in electrophoresis. Flow cytometric analysis revealed G0/G1 stage cell blocking phenomena, the hypodiploid apoptotic cell increased, displayed typical peak of apoptosis, the rate of cell apoptosis and YQJP serum concentration were in a dose-dependent manner. The result of hybridization showed that 30% of YQJP serum could inhibit apoptotic gene bcl-2 expression, upregulated the level of apoptogenous gene c-myc and p53 mRNA.

CONCLUSION

VSMC apoptosis could be induced by YQJP recipe and its mechanism might be through affecting the apoptosis related gene expression activity.