OBJECTIVETo investigate the effect of rat Schwann cell secretion on the proliferation and differentiation of human embryonic neural stem cells (NSCs).

METHODSThe samples were divided into three groups. In Group One, NSCs were cultured in DMED/F12 in which Schwann cells had grown for one day. In Group Two, NSCs and Schwann cells were co-cultured. In Group Three, NSCs were cultured in DMEM/F12. The morphology of NSCs was checked and beta-tubulin, GalC, hoechst 33342 and GFAP labellings were detected.

RESULTSIn Group One, all neural spheres were attached to the bottom and differentiated. The majority of them were beta-tubulin positive while a few of cells were GFAP or GalC positive. In Group Two, neural spheres remained undifferentiated and their proliferation was inhibited in places where Schwann cells were robust. In places where there were few Schwann cells, NSCs performed in a similar manner as in Group One. In Group Three, the cell growth state deteriorated day after day. On the 7th day, most NSCs died.

CONCLUSIONThe secretion of rat Schwann cells has a growth supportive and differentiation-inducing effect on human NSCs.

Animals ; Brain ; cytology ; embryology ; Cell Differentiation ; drug effects ; Cell Division ; drug effects ; Coculture Techniques ; Humans ; Rats ; Rats, Sprague-Dawley ; Schwann Cells ; secretion ; Sciatic Nerve ; cytology ; Stem Cells ; cytology

BACKGROUNDThe development and maintenance of spiral ganglion cells (SGCs) appear to be supported by neurotrophins. Removal of this support leads to their gradual degeneration. Intracochlear infusion with neurotrophins can provide trophic support to SGCs in animal deafness models if given shortly after deafening. However, it is not known whether delayed intervention will provide similar protection, which might be clinically relevant. The present research was conducted to determine the effects of brain-derived neurotrophic factor (BDNF) administration on the capacity of the peripheral processes to resprout.

METHODSThe left cochlea of 20 profoundly deafened rats, which were divided into 2 groups equally, was implanted with an electrode and drug-delivery system 30 days after deafening. Either BDNF or artificial perilymph (AP) was delivered continuously for 28 days. Electrically evoked auditory brainstem responses (EABRs) were recorded during the period. SGC body and peripheral process density were measured.

RESULTSThe EABR thresholds of AP increase continually. Those of BDNF increase slowly at the beginning then decrease, and were significantly less than those of the AP group from day 14 to 28 (P < 0.01). In terms of SGC and peripheral process density, the difference between the treated and control ears of BDNF group was clearly significant (P < 0.01), but not in AP group (P > 0.05). Analysis of the left cochlea between the two groups demonstrated that SGC/peripheral process density of the BDNF group was significantly greater than that of the AP group. Finally, a functional formula was developed relating the last EABR threshold and SGC density and process density, which was as follows: T = 466.184 - 2.71 (F.B.L).

CONCLUSIONSUnder the conditions of delayed intervention following 30 days after deafening in rats, it can be concluded that BDNF enhances SGC bodies and peripheral processes survival after differentiation and so improves auditory sensitivity. SGC peripheral processes influence the auditory sensitivity.

Animals ; Brain-Derived Neurotrophic Factor ; administration & dosage ; Cell Survival ; drug effects ; Evoked Potentials, Auditory, Brain Stem ; drug effects ; Male ; Rats ; Rats, Sprague-Dawley ; Spiral Ganglion ; cytology ; drug effects

OBJECTIVETo study the flavanoids extracted from onion on the blood-brain barrier (BBB) permeation, and their effects on primary cultured neuron cell proliferation and apoptosis of SD rats using ethanol reflux method.

METHODSThe brain microvascular endothelial cells (BMVECs) were first successfully primary cultured. Then rats BMVECs and astrocytes (ACs) were co-cultured to establish the in vitro BBB model. The flavanoids were extracted from onion using ethanol reflux method. The model was verified by transmission electron microscopy (TEM) and trans-epithelial electric resistance (TEER). The flavanoids permeability was tested using high performance liquid chromatography (HPLC). Meanwhile, rat neuron cells were cultured and exposed to H2O2 and flavanoids. Their effects on the cell proliferation and apoptosis were observed using MTT assay. The injury of neuron DNA was analyzed using single-cell gel electrophoresis (SCGE) and immunofluorescent assay.

RESULTSThe in vitro BBB model was successfully established by TEM and TEER. Results of HPLC proved flavanoids extracts could effectively permeate the BBB with the permeability of 60.58%. The extractive at 10 - 20 microg/mL showed obvious inhibition on the apoptosis of neuron cells induced by H2O2, and attenuated the injury of neuron DNA.

CONCLUSIONSThe flavanoids extracted from onion ethanol reflux method could effectively penetrate the BBB. They also showed obvious inhibition on the H2O2 induced neuron cell apoptosis and DNA injury.

Animals ; Animals, Newborn ; Apoptosis ; Astrocytes ; cytology ; drug effects ; Blood-Brain Barrier ; drug effects ; Cells, Cultured ; DNA Damage ; Endothelial Cells ; cytology ; drug effects ; Flavonoids ; pharmacology ; Hydrogen Peroxide ; Neurons ; cytology ; drug effects ; Neuroprotective Agents ; pharmacology ; Onions ; chemistry ; Rats

Animals ; Apoptosis ; drug effects ; Brain Ischemia ; pathology ; Hippocampus ; cytology ; drug effects ; pathology ; Neurons ; drug effects ; pathology ; Rats ; Rats, Wistar ; Reperfusion Injury ; pathology ; Sulfinic Acids ; pharmacology

Many extracellular matrix molecules are expressed in the embryonic nervous system and there is some evidence that they are important regulators of neural development. Of these molecules, laminin appears to be the most potent, affecting virtually all neurons of the peripheral and central nervous system. This study was undertaken to investigate the effects of laminin on the proliferation and differentiation of cultured neuroepithelial cells taken from fetal rat forebrains (embryonic day 17-19). The results are summarized as follows. 1) Neuroepithelial cells cultivated in epidermal growth factors containing serum-free medium subsequently differentiated into neurons, astrocytes, and oligodendrocytes. 2) Neuronal cells derived from neuroepithelial cells were immunoreactive for gamma-aminobutyric acid (GABA) or substance P, but were not for serotonin and tyrosine hydroxylase. 3) In western blot analysis, the phosphorylated neurofilament content in neuronal cells was higher in culture on laminin than in culture on poly-L-lysine (PLL). 4) The proliferation rate of GABAergic neurons was higher in culture on laminin than in culture on PLL. These results suggest that GABAergic and substance P-ergic neurons can be differentiated from neuroepithelial cells and that laminin promotes the differentiation of neuronal cells from neuroepithelial cells and the increased proliferation rate of GABAergic cells.
Animal ; Brain/drug effects* ; Brain/cytology ; Cell Aging/drug effects ; Cell Differentiation/drug effects ; Cell Division/drug effects ; Cells, Cultured ; Epidermal Growth Factor/pharmacology* ; Epithelial Cells/drug effects ; Epithelial Cells/cytology ; GABA/physiology ; Laminin/pharmacology* ; Neurons/physiology ; Neurons/drug effects* ; Neurons/cytology* ; Rats/embryology

OBJECTIVETo investigate the differentiation of bone marrow stromal cells (BMSC) into neuron-like cells and to explore their potential use for neural transplantation.

METHODSBMSC from rats and adult humans were cultured in serum-containing media. Salvia miltiorrhiza was used to induce human BMSC (hBMSC) to differentiate. BMSC were identified with immunocytochemistry. Semi-quantitative RT-PCR was used to examine mRNA expression of neurofilamentl (NF1), nestin and neuron-specific enolase (NSE) in rat BMSC (rBMSC). Rat BMSC labelled by Hoschst33258 were transplanted into striatum of rats to trace migration and distribution.

RESULTSrBMSC expressed NSE, NF1 and nestin mRNA, and NF1 mRNA and expression was increased with induction of Salvia miltiorrhiza. A small number of hBMSC were stained by anti-nestin, anti-GFAP and anti-S100. Salvia miltiorrhiza could induce hBMSC to differentiate into neuron-like cells. Some differentiated neuron-like cells, that expressed NSE, beta-tubulin and NF-200, showed typical neuron morphology, but some neuron-like cells also expressed alpha smooth muscle protein, making their neuron identification complicated. rBMSC could migrate and adapted in the host brains after being transplanted.

CONCLUSIONBone marrow stromal cells could express phenotypes of neurons, and Salvia miltiorrhiza could induce hBMSC to differentiate into neuron-like cells. If BMSC could be converted into neurons instead of mesenchymal derivatives, they would be an abundant and accessible cellular source to treat a variety of neurological diseases.

Animals ; Bone Marrow Transplantation ; Brain ; cytology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Male ; Neurons ; cytology ; drug effects ; Plant Extracts ; Rats ; Rats, Sprague-Dawley ; Salvia miltiorrhiza ; Stromal Cells ; cytology ; drug effects ; transplantation

In this work, blank polylactic acid (PLA) nanoparticles with unstained surface were prepared by the nano-deposition method. On the basis of the preparation, the effect of surface modification on brain microvascular endothelial cells (BMECs) targeting was examined by in vivo experiments and fluorescence microscopy. The results showed that PLA nanoparticles are less toxic than PACA nanoparticles but their BMECs targeting is similar to PACA nanoparticles. The experiments suggest that drugs can be loaded onto the particles and become more stable through adsorption on the surface of PLA nanoparticles with high surface activity. The surface of PLA nanoparticles was obviously modified and the hydrophilicity was increased as well in the presence of non-ionic surfactants on PLA nanoparticles. As a targeting moiety, polysobate 80 (T-80) can facilitate BMECs targeting of PLA nanoparticles.
Brain/*blood supply ; Brain/drug effects ; Capillaries/cytology ; Capillary Permeability/drug effects ; Drug Delivery Systems ; Endothelium, Vascular/*cytology ; Lactic Acid/*pharmacology ; Mice, Inbred Strains ; Microscopy, Fluorescence ; Nanoparticles ; Polymers/*pharmacology

OBJECTIVETo explore the mechanism of borneol in opening the blood-brain barrier (BBB).

METHODSBorneol contained serum was prepared and using Matin-Darby canine kidney epithelium (MDCKE) cell line as the in vitro BBB model to observe the effects of borneol on intercellular tight junction (ICTJ) and pinocytosis vesicles of BBB model.

RESULTSBorneol reduced the ICTJ and caused increase of the number and enlarged the diameter of vesicles. The ICTJ was opened firstly 4 hrs after borneol treatment, then the pinocytosis was affected 24 hrs later. The effects disappeared 24 hrs after removal of the borneol contained serum, indicating that the above-mentioned effects were reversible.

CONCLUSIONBorneol could obviously loosen the ICTJ in BBB, accelerate the transportation of substance through the intercellular passage, it also could increase the number and volume of pinocytosis vesicles in BBB cells, thus to accelerate the transportation of substance by way of cell pinocytosis.

Animals ; Blood-Brain Barrier ; drug effects ; physiology ; Bornanes ; pharmacology ; Cell Line ; Cell Membrane Permeability ; Epithelial Cells ; cytology ; Kidney ; cytology ; Male ; Models, Neurological ; Pinocytosis ; drug effects ; Rabbits ; Tight Junctions ; drug effects

OBJECTIVETo study the effect of HIV-1 gp41 ectodomain (gp41-I90) on the cytoskeletal changes in human brain microvascular endothelial cells (HBMECs) induced by Cryptococcus neoformans.

METHODSHBMECs were cultured on collagen-coated chamber slide or transwell to allow the formation of cell monolayers. After pre-treatment with gp41-I90 and infection with Cryptococcus neoformans, the HBMECs were examined for the expression of actin or filamin by immunofluorescence assay. HRP permeability of the HBMECs treated with gp41-I90 was detected by ELISA. Transcytosis of Cryptococcus neoformans through the gp41-I90-treated HBMECs was detected by direct counting from a hemocytometer.

RESULTSgp41-I90 obviously enhanced the cytoskeletal changes of the HBMECs infected by Cryptococcus neoformans, causing curved and sparse filamentous arrangement of actin and filamin. gp41-I90 treatment also resulted in obviously increased HRP permeability of the cells and transcytosis of Cryptococcus neoformans.

CONCLUSIONgp41- I90 enhances Cryptococcus neoformans binding to HBMECs, which is related to its effect in enhancing Cryptococcus neoformans-induced cytoskeletal changes of the cells.

Brain ; blood supply ; Cells, Cultured ; Cryptococcosis ; pathology ; Cryptococcus neoformans ; pathogenicity ; Cytoskeleton ; drug effects ; metabolism ; Endothelial Cells ; cytology ; drug effects ; microbiology ; Endothelium, Vascular ; cytology ; drug effects ; metabolism ; HIV Envelope Protein gp41 ; pharmacology ; Humans ; Microcirculation

OBJECTIVE: To investigate the effect of brain tissue extracts in neonate rats with hypoxic-ischemic brain damage (HIBD) on the differentiation of bone marrow stromal cells (BMSCs) into neural cells. METHODS: Fifteen 7-day-old neonate rats were induced HIBD by left carotid artery ligation and hypoxia exposure, and another 15-day-old neonate rats were served as normal rats. The left and right brain tissue extracts of the normal and HIBD rats were prepared 24 h after the HIBD (8-day old), 72 h after the HIBD (10-day old), and 7 d after the HIBD (14-day old), respectively (n=5). The rat BMSCs of passage 3-5 were cultured in the medium with or without previous brain tissue extracts. The expressions of neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP) and O(4) marked oligodendrocyte were detected after 3 days by immunocytochemistry. RESULTS: The expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left or right brain tissue extracts of different day old normal rats were higher than those of BMSCs cultured without the extracts, respectively (P<0.01), and the expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left brain tissue extracts of 8 day old and 10 day old HIBD rats were higher than those of BMSCs cultured with right brain tissue extracts of the same day HIBD rats and BMSCs cultured with left or right brain tissue extracts of the same day normal rats (P<0.01 or P<0.05). The expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left brain tissue extracts of 8-day-old HIBD rats were higher than those of BMSCs cultured with left brain tissue extracts of 10-day-old and 14-day-old HIBD rats (P<0.01 or P<0.05). CONCLUSION The brain tissue extracts of normal and HIBD rats can induce BMSCS into neural cells, and the damaged brain tissue extracts of 8-day-old HIBD rats is the best inductor.
Animals ; Animals, Newborn ; Brain ; metabolism ; Cell Differentiation ; Cells, Cultured ; Hypoxia-Ischemia, Brain ; metabolism ; Mesenchymal Stem Cells ; cytology ; drug effects ; Neurons ; cytology ; drug effects ; Rats ; Rats, Sprague-Dawley ; Tissue Extracts ; pharmacology