Latest ArticlesThe main ingredient of extractable petroleum ether of Polyrhachis vicina Roger (EPPR) is octadecene unsaturated fatty acids.Mounting evidence supports that N-3 polyunsaturated fatty acids can attenuate neuroinflammation, reduce oxidative stress, then protect neurons.In order to explore the effect of EPPR on the inflammatory response of depressed rats, the model of depression was established by chronic unpredictable mild stress (CUMS).Sucrose preference test, forced swimming test were employed to investigate the anti-depressive effect of EPPR in rat.The activation of glial cells and astrocytes in the prefrontal cortex of depressed rats was observed by immunofluorescence.The levels of inflammatory factors were measured by Quantitative Real-time PCR.NF-κB was detected by immunoblotting.EPPR could significantly improve the depressive behavior of rats, decrease NF-κB translocation to the compartment of nucleus, down-regulate the pro-inflammatory cytokines IL-1β, TNF-α and indoleamine 2, 3-dioxygenase (IDO) gene expression levels, inhibit the activation of microglia and astrocytes in depressed rats.These results suggest that EPPR could notably ameliorate inflammation induced by chronic stress, and the protective effect might be linked to the regulation of NF-κB p65.
Drug-resistance is a challenge in the treatment of epilepsy, and traditional Chinese medicine (TCM) prescription may have a potential in therapy of the epilepsy.Here we established a modified 6 Hz corneal kindled mouse model of epilepsy, and verified its drug-resistance to four commonly used western medicines.We evaluated the efficacy of three classical TCM prescriptions in this drug-resistant epilepsy model.The results showed that:① most C57BL/6J mice with stimulation current intensity at 44 mA (8 out of 10) were fully kindled, while none ICR mice with stimulation current intensity at 44 mA or C57BL/6J mice with stimulation current intensity at 24 mA were fully kindled.Fully kindled mice exhibited epileptic electroencephalograms after 44 mA and 6 Hz corneal kindling stimulation and increased activation of astrocytes in the hippocampus (by staining the glial fibrillary acidic protein); ② 50 mg·kg-1 phenytoin sodium, 100 mg·kg-1 valproic acid sodium and 15 mg·kg-1 lamotrigine had no significant effects on the drug-resistant seizures in 6 Hz corneal kindled C57BL/6J mice, while 100 mg·kg-1 levetiracetam significantly reduced the seizure stage (P < 0.05) and incidence of generalized seizure (P < 0.05) in it; ③ TCM prescriptions, Chai-Hu Plus Long-Gu Mu-Li decoction (9.36 or 28.08 g·kg-1) and Tian-Ma Gou-Teng decoction (14.82 or 44.46 g·kg-1), had no significant effects on the drug-resistant seizures in 6 Hz corneal kindled C57BL/6J mice, while TCM prescription Feng-Yin decoction (19.11 g·kg-1) significantly reduced both the seizure stage (P < 0.01) and incidence of generalized seizure (P < 0.05) in it.Thus, the modified 6 Hz corneal kindled C57BL/6J mouse model is an excellent drug-resistant epilepsy model, Feng-Yin decoction have antiepileptic effects on it, suggesting Feng-Yin decoction may be an effective TCM prescription for clinical treatment of drug-resistant epilepsy.
Alzheimer's disease (AD) is the most common neurodegenerative disease in the aging population.Abnormal hyperphosphorylation of tau is the main cause of AD.Protein phosphatases 2A (PP2A) can increase the hyperphosphorylation of tau.Cornel iridoid glycoside (CIG) is one of the main components extracted from Cornus of ficinalis.The aim of the present study was to investigate the effects and the underlying mechanisms of CIG on enhancing PP2A activity.SK-N-SH cells were exposed to 20 nmol·L-1 okadaic acid (OA, an inhibitor of PP2A) for 6 h to induce the hyper-phosphorylation of tau, in order to define the effect of CIG on the activity of PP2A and posttranslational modification of PP2A catalytic subunit C (PP2Ac).We found that OA significantly decreased PP2A activity, increased the phosphorylation of PP2Ac, and enhanced tau hyper-phosphorylation.Pre-incubation of CIG significantly attenuated the OA-induced tau hyper-phosphorylation at Ser 199/202 and Ser 396, and recovered the activity of PP2A.CIG inhibited PP2Ac phosphorylation at Tyr 307 and increased Src phosphorylation.In conclusion, the mechanism of CIG inhibition of tau hyper-phosphorylation was activation of PP2A to reduce the level of p-Src for a reduction of PP2Ac phosphorylation at Tyr307.
Alzheimer's disease (AD) is a type of common neurodegenerative disease.The main clinical symptom of the disease is progressive cognitive dysfunction, which has no effective therapy yet.With the in-depth immunology study in the central nervous system, studies in different fields such as preclinical phase, genetics and bioinformatics have shown that immune dysfunction contribute to the pathogenesis of AD, including the beginning, maintenance and deterioration stage in AD.China has a wealth of natural medicine resources and clinical experiences.A large number of natural drugs and effective components both can regulate the immune function and ameliorate the symptoms in AD.This review summarizes the researches of ameliorating the symptoms in AD through immunization regulation in recent years with an aim to provide new ideas and clues in the study of new anti-AD drugs using natural medicines.
The discussion on pathophysiological of multiple sclerosis (MS) mainly focuses on T and B cells in adaptive immune response, but less involve in the myeloid cells (dendritic cells, monocytes, macrophages and microglia) in the innate immune system, which also play an important role in the pathogenesis of MS. The myeloid cell population acts as antigen-presenting cells and effector cells in neuroinflammation in the innate immune system. The interactions between T cells and myeloid cells form a vicious cycle which makes the disease continuous deterioration. At present, the studies on the therapeutic drugs for MS mainly are focused on the adaptive immune system, but pay less attention to myeloid cells. In this article, we reviewed the sub-types and functions of myeloid cells, their changes in MS patients and animal models, as well as the effects of some therapeutic drugs for MS on myeloid cells, in the purpose of finding new targets and strategies for development for MS therapy.
Progressive accumulation of the amyloid-β peptide (Aβ) in the brain plays a central role in the pathogenesis of Alzheimer's disease (AD).The animal model of intracerebral injection of Aβ oligomers not only provides a method for further exploring the mechanism of Aβ in AD, but also can be used to screen drug candidates targeting Aβ oligomers.This animal model has been widely used in the study of anti-AD drugs and mechanism of AD.In this paper, we summarize the research progress in the animal model of intracerebral injection of soluble Aβ oligomers, including experimental animals, the types of Aβ, the preparation of Aβ oligomers in vitro, injection sites and doses, the duration of modeling, animal behavioral changes, and the pathological mechanisms relating to this animal model, which will contribute to the application of the animal model to various conditions.
Stroke is the leading cause of death in Chinese currently, characterized by high incidence, high morbidity and high mortality, of which ischemic stroke accounted for 87%.However, it still lacks the ideal treatment.Stem cells are a class of cells with self-renewal ability and high differentiation potential.Stem cell transplantation breaks the irreversibility of nerve injury to post-stroke infarct area.However, stem cells also requiring specific chemokines to promote their directional migration to the injured tissue site after transplanted.Stromal cell-derived factor-1α (SDF-1α) is one of the typical chemokines.SDF-1α and its specific receptor CXCR4 can induce its migration, increase its proliferation and promote angiogenesis.In this paper, the role of SDF-1α/CXCR4 axis in the treatment of ischemic stroke in stem cells is reviewed in order to provide a theoretical basis for enhancing the efficacy of stem cell transplantation in the treatment of ischemic stroke.
Macrolide antibiotics have been widely utilized in the treatment of bacterial infections due to their strengths, low toxicity, and high efficacy. Because of the widespread application of macrolide drugs, the emergence of antibacterial resistance against antibiotics has become prominent. Ketolides, as the third generation macrolides, display improvement in activities against macrolide-resistant pathogens with broad antibacterial spectrum. Due to hepatotoxicity, the use of telithromycin has been limited. It is urgent to identify the novel sources of ketolides. So the structural modification of ketolides become the main research field of macrolide. This review introduces the recent progress in the structural modification of ketolide, with the purpose of providing support to development of new ketolide antibiotics.
Shikimate kinase is a key protein of the shikimic pathway, which is essential for the survival of Mycobacterium tuberculosis. In this study, a screening assay for Mycobacterium tuberculosis shikimate ki-nase (MtSK) inhibitor was developed. A 120 000-compound library was screened by the enzyme assay and the phenotype screening using Mycobacterium smegmatis. A hit compound named IMB-T5297[(E)-3-(3-(3-chloro-5-methoxy-4-(prop-2-yn-1-yloxy)phenyl)acryloyl)-6-methyl-2H-pyran-2, 4(3H)-dione] was identified to be a selective inhibitor of MtSK with a half maximal inhibitory concentration (IC50) value of 1.745 μg·mL-1, which also showed antibacterial activity. The interaction between compound and protein was analyzed by surface plasmon resonance (SPR) experiment, which showed the KD value was 2.151×10-5 mol·L-1. The binding model of MtSK and compound was simulated by the computer program. Five key amino acids in the binding pocket were indispensable site-directed mutated to verify the model. IMB-T5297 inhibited Mycobacterium tuberculosis H37Rv with a minimum inhibitory concentration (MIC) value of 49.723 μg·mL-1 and displayed low cytotoxicity to mammalian cells. In this study, IMB-T5297 was identified as a selective inhibitor of MtSK enzyme with anti-tuberculosis activity. With additional structural modification, the compound has a potential to become a novel anti-tuberculosis compound.
9-Acetoxycycloberberine (1) with a unique skeleton was first identified to display a potent antimicrobial profile against methicillin-resistant Staphylococcus aureus (MRSA) with MIC values of 1-16 μg·mL-1. Taking the compound as a lead, 14 target cycloberberine analogues with diverse structures, such as berberine and chelerythrine derivatives, were synthesized and evaluated for their anti-bacterial activities. Analysis of the structure-activity relationship revealed that:① ring E was essential for the activity; ② the removing of ring B decreased the activity against MRSA. However, the antimicrobial activity against vancomycin-resistant Enterococcus faecium (VRE) was improved; ③ the introduction of a suitable rigid substituent at the 9-position was beneficial for the activity. Among them, compound 9a showed the most potential activity against methicillin-sensitive Staphylococcus aureus (MSSA) and MRSA isolates with MIC values of 0.5-1 μg·mL-1, suggesting a different mechanism from clinical drugs. It displayed higher stability in blood. Therefore, we consider 9a worthy of further investigation. The results provide key scientific evidence for development of such compounds into a new type of anti-MRSA candidates.