Excessive microglial activation and subsequent neuroinflammation lead to neuronal cell death, which are involved in the pathogenesis and progression of several neurodegenerative diseases such as Parkinson's disease. The objective of this study was to determine the involvement of chlorpyrifos (CPF) in the activation of microglia and production of inflammatory factors in response to CPF stimulation and the influence on the viability of dopaminergic (DA) neurons. We detected the change of BV-2 cells morphology and expression of inducible nitric oxide (iNOS), cyclooxygenase-2 (COX-2) mRNA and protein level upon CPF stimulation (0, 1, 3, 6, 12, 24 h) in BV-2 (mouse brain microglia) cells by reverse transcription polymerase chain reaction (RT-PCR) or Western blot. We randomly assigned BV-2 cells into CPF, menstruum dimethysulfoxide (DMSO) and normal saline (NS) groups. We stimulated The BV-2 cells in the CPF group with CPF, and we stimulated the two control groups with DMSO or NS for 12 hours, respectively. We then collected the used culture media from the culture dishes and centrifuged it to remove the detached cells. Then, we used the supernatants as microglial conditioned media. We treated SH-SY5Y neurons with various groups of microglial conditioned media for 24 hours. We observed the effect of conditioned media collected from BV-2 cell on the viability of dopaminergic cell lines SH-SY5Y using MTT assay. We found that inflammatory factors iNOS, COX-2 mRNA and protein levels were up-regulated upon CPF stimulation. Conditioned media from BV-2 upon CPF stimulation is toxic to SH-SY5Y. It might be concluded that the exposure to CPF may induce dopaminergic neuronal damage by the activation of inflammatory response, and a mechanism may be involved in Parkinson's disease pathogenesis.
1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (Sal) is a kind of catechol isoquinoline compound, which mainly exists in mammalian brain and performs a variety of biological functions. Through in vivo metabolism, Sal can be transformed into endogenous neurotoxins and can participate the occurrence of Parkinson’s disease (PD). This has attracted widespread concern of researchers. Recently, many research works have shown that Sal may lead to alcohol addiction and regulate hormone release of the neuroendocrine system, which indicated that it is a potential regulator of dopaminergic neurons. In this paper, we discuss the neural functions of Sal on the above aspects, and wish to provide some theoretical supports for further research on its mechanism.
ObjectiveTo prepare dopamine modified and cartilage derived morphogenetic protein 1 (CDMP1) laden polycaprolactone-hydroxyapatite (PCL-HA) composite scaffolds by three-dimensional (3D) printing and evaluate the effect of 3D scaffolds on in vitro chondrogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs).MethodsA dimensional porous PCL-HA scaffold was fabricated by 3D printing. Dopamine was used to modify the surface of PCL-HA and then CDMP-1 was loaded into scaffolds. The surface microstructure was observed by scanning electron microscope (SEM) and porosity and water static contact angle were also detected. The cytological experiment in vitro were randomly divided into 3 groups: group A (PCL-HA scaffolds), group B (dopamine modified PCL-HA scaffolds), and group C (dopamine modified and CDMP-1 laden PCL-HA scaffolds). The hBMSCs were seeded into three scaffolds, in chondrogenic culture conditions, the cell adhesive rate, the cell proliferation (MTT assay), and cell activity (Live-Dead staining) were analyzed; and the gene expressions of collagen type Ⅱ and Aggrecan were detected by real-time fluorescent quantitative PCR.ResultsThe scaffolds in 3 groups were all showed a cross-linked and pore interconnected with pore size of 400–500 μm, porosity of 56%, and fiber orientation of 0°/90°. For dopamine modification, the scaffolds in groups B and C were dark brown while in group A was white. Similarly, water static contact angle was from 76° of group A to 0° of groups B and C. After cultured for 24 hours, the cell adhesion rate of groups A, B, and C was 34.3%±3.5%, 48.3%±1.5%, and 57.4%±2.5% respectively, showing significant differences between groups (P<0.05). Live/Dead staining showed good cell activity of cells in 3 groups. MTT test showed that hBMSCs proliferated well in 3 groups and the absorbance (A) value was increased with time. The A value in group C was significantly higher than that in groups B and A, and in group B than in group A after cultured for 4, 7, 14, and 21 days, all showing significant differences (P<0.05). The mRNA relative expression of collagen type Ⅱ and Aggrecan increased gradually with time in 3 groups. The mRNA relative expression of collagen type Ⅱafter cultured for 7, 14, and 21 days, and the mRNA relative expression of Aggrecan after cultured for 14 and 21 days in group C were significantly higher than those in groups A and B, and in group B than in group A, all showing significant differences (P<0.05).ConclusionCo-culture of dopamine modified and CDMP1 laden PCL-HA scaffolds and hBMSCs in vitro can promote hBMSCs’ adhesion, proliferation, and chondrogenic differentiation.
Objective To develop a drug-loaded composite microsphere that can simultaneously release the berberine (BBR) and naringin (NG) to repair infectious bone defects. MethodsThe NG was loaded on mesoporous microspheres (MBG) to obtain the drug-loaded microspheres (NG-MBG). Then the dual drug-loaded compound microspheres (NG-MBG@PDA-BBR) were obtained by wrapping NG-MBG with polydopamine (PDA) and modifying the coated PDA with BBR. The composite microspheres were characterized by scanning electron microscopy, X-ray diffraction, specific surface area and pore volume analyzer, and Fourier transform infrared spectroscopy; the drug loading rate and release of NG and BBR were measured; the colony number was counted and the bacterial inhibition rate was calculated after co-culture with Staphylococcus aureus and Escherichia coli for 12 hours to observe the antibacterial effect; the biocompatibility was evaluated by live/dead cell fluorescence staining and cell counting kit 8 assay after co-culture with rat’s BMSCs for 24 and 72 hours, respectively, and the osteogenic property was evaluated by alkaline phosphatase (ALP) staining and alizarin red staining after 7 and 14 days, respectively. Results NG-MBG@PDA-BBR and three control microspheres (MBG, MBG@PDA, and NG-MBG@PDA) were successfully constructed. Scanning electron microscopy showed that NG-MBG@PDA-BBR had a rough lamellar structure, while MBG had a smooth surface, and MBG@PDA and NG-MBG@PDA had a wrapped agglomeration structure. Specific surface area analysis showed that MBG had a mesoporous structure and had drug-loading potential. Low angle X-ray diffraction showed that NG was successfully loaded on MBG. The X-ray diffraction pattern contrast showed that all groups of microspheres were amorphous. Fourier transform infrared spectroscopy showed that NG and BBR peaks existed in NG-MBG@PDA-BBR. NG-MBG@PDA-BBR had good sustained drug release ability, and NG and BBR had early burst release and late sustained release. NG-MBG@PDA-BBR could inhibit the growth of Staphylococcus aureus and Escherichia coli, and the antibacterial ability was significantly higher than that of MBG, MBG@PDA, and NG-MBG@PDA (P<0.05). But there was a significant difference in biocompatibility at 72 hours among microspheres (P<0.05). ALP and alizarin red staining showed that the ALP positive area and the number of calcium nodules in NG-MBG@PDA-BBR were significantly higher than those of MBG and NG-MBG (P<0.05), and there was no significant difference between NG-MBG@PDA and NG-MBG@PDA (P>0.05). Conclusion NG-MBG@PDA-BBR have sustained release effects on NG and BBR, indicating that it has ideal dual performance of osteogenesis and antibacterial property.