Anti-inflammatory effects of a fluorovinyloxyacetamide compound KT-15087 in microglia cells

The microglial activation plays an important role in the progression of neurodegenerative diseases by secreting various proinflammatory cytokines and neurotoxic factors. Inhibition of microglial activation may alleviate neurodegenerative processes. To search for novel therapeutic agents against neuroinflammatory diseases, several fluorovinyloxyacetamide derivatives were screened for anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated microglial cells. From cell-based screening, it was found that a novel synthetic compound KT-15087 markedly attenuated the production of nitric oxide (NO) and tumor necrosis factor (TNF)-α in microglial cells. KT-15087 also suppressed the gene expression of inducible nitric oxide synthase (iNOS), TNF-α and interleukin (IL)-1β. The compound inhibited the nuclear translocation and DNA binding of NF-κB as well as the phosphorylation of p38 mitogen-activated protein kinases (MAPK) and c-jun N-terminal kinase (JNK). Moreover, KT-15087 showed a neuroprotective activity by reducing the cytotoxicity of LPS-stimulated microglia toward B35 neuroblastoma cells in the coculture. The neuroprotective activity of the compound was most effective when microglia were pretreated with the compound prior to LPS challenge. Taken collectively, KT-15087 has an anti-inflammatory activity in microglia, and might have a therapeutic potential for the treatment of neuroinflammatory diseases.     

Microglia signaling as a target of donepezil

Donepezil is a reversible and noncompetitive cholinesterase inhibitor. The drug is considered as a first-line treatment in patients with mild to moderate Alzheimer's disease. Recently, anti-inflammatory and neuroprotective effects of the drug have been reported. “Cholinergic anti-inflammation pathway” has major implications in these effects. Here, we present evidence that donepezil at 5-20 μM directly acts on microglial cells to inhibit their inflammatory activation. Our conclusion is based on the measurement of nitric oxide and proinflammatory mediators using purified microglia cultures and microglia cell lines: donepezil attenuated microglial production of nitric oxide and tumor necrosis factor (TNF)-α, and suppressed the gene expression of inducible nitric oxide synthase, interleukin-1β, and TNF-α. Subsequent studies showed that donepezil inhibited a canonical inflammatory NF-κB signaling. Microglia/neuroblastoma coculture and animal experiments supported the anti-inflammatory effects of donepezil. Based on the studies using nicotinic acetylcholine receptor antagonists, the donepezil inhibition of microglial activation was independent of acetylcholine and its receptor. Thus, inflammatory activation signaling of microglia may be one of the direct targets of donepezil in the central nervous system. It should be noted, however, that there is a large gap between the therapeutic dose of the drug used clinically and the concentration of the drug that exerts the direct action on microglial cells.     

Melatonin alleviates intestinal injury,neuroinflammation and cognitive dysfunction caused by intestinal ischemia/reperfusion

Intestinal ischemia/reperfusion (I/R) can cause multiple organ damage with extremely high morbidity and mortality. Melatonin has anti-inflammatory, anti-oxidative and anti-apoptotic effects against various diseases. This study aimed to explore whether melatonin had a protective effect against intestinal I/R-induced neuroinflammation and cognitive dysfunction, and investigate its potential mechanisms. In this study, melatonin was administered to the rats with intestinal I/R, then histological changes in intestine and brain (frontal cortex and hippocampal CA1 area) tissues and cognitive function were detected, respectively. The encephaledema and blood–brain barrier (BBB) permeability were observed. Moreover, the alterations of proinflammatory factors (tumor necrosis factor-α, interleukin-6 and interleukin-1β), oxidative response (malondialdehyde, superoxide dismutase, and reactive oxygen species), apoptosis and proteins associated with inflammation, including Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (Myd88) and phosphorylated nuclear factor kappa beta (NF-κB), and apoptosis (cleaved caspase-3) in brain tissues were examined. Furthermore, the expressions of TLR4, Myd88, and microglial activity were observed by multiple immunofluorescence staining. The results showed that intestinal I/R-induced abnormal neurobehavior and cerebral damage were ameliorated after melatonin treatment, which were demonstrated by improved cognitive dysfunction and aggravated histology. Furthermore, melatonin decreased the levels of proinflammatory factors and oxidative stress in plasma, intestine and brain tissues, attenuated apoptotic cell, and inhibited the expressions of related proteins and the immunoreactivity of TLR4 or Myd88 in microglia in brain tissues. These findings showed that melatonin might relieve neuroinflammation and cognitive dysfunction caused by intestinal I/R, which could be, at least partially, related to the inhibition of the TLR4/Myd88 signaling in microglia.     

Microglial dysfunction in brain aging and Alzheimer's disease

Microglia, the immune cells of the central nervous system, have long been a subject of study in the Alzheimer's disease (AD) field due to their dramatic responses to the pathophysiology of the disease. With several large-scale genetic studies in the past year implicating microglial molecules in AD, the potential significance of these cells has become more prominent than ever before. As a disease that is tightly linked to aging, it is perhaps not entirely surprising that microglia of the AD brain share some phenotypes with aging microglia. Yet the relative impacts of both conditions on microglia are less frequently considered in concert. Furthermore, microglial “activation” and “neuroinflammation” are commonly analyzed in studies of neurodegeneration but are somewhat ill-defined concepts that in fact encompass multiple cellular processes. In this review, we have enumerated six distinct functions of microglia and discuss the specific effects of both aging and AD. By calling attention to the commonalities of these two states, we hope to inspire new approaches for dissecting microglial mechanisms.     

A novel SIRT6 activator ameliorates neuroinflammation and ischemic brain injury via EZH2/FOXC1 axis

Ischemic stroke is the second leading cause of death worldwide with limited medications and neuroinflammation was recognized as a critical player in the progression of stroke, but how to control the overactive neuroinflammation is still a long-standing challenge. Here, we designed a novel SIRT6 activator MDL-811 which remarkably inhibited inflammatory response in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and primary mouse microglia, which were abolished by silencing SIRT6. RNA-seq screening identified the forkhead box C1 (Foxc1) is a key gene evoked by MDL-811 stimulation and is required for the anti-inflammatory effects of MDL-811. We found MDL-811-activated SIRT6 directly interacted with enhancer of zeste homolog 2 (EZH2) and promoted deacetylation of EZH2 which could bind to the promoter of Foxc1 and upregulate its expression to modulate inflammation. Moreover, our data demonstrated that MDL-811 not only ameliorated sickness behaviors in neuroinflammatory mice induced by LPS, but also markedly reduced the brain injury in ischemic stroke mice in addition to promoting long-term functional recovery. Importantly, MDL-811 also exhibited strong anti-inflammatory effects in human monocytes isolated from ischemic stroke patients, underlying an interesting translational perspective. Taken together, MDL-811 could be an alternative therapeutic candidate for ischemic stroke and other brain disorders associated with neuroinflammation.     

Amantadine protects dopamine neurons by a dual action: reducing activation of microglia and inducing expression of GNDF in astroglia

Amantadine is commonly given to alleviate L-DOPA-induced dyskinesia of Parkinson’s disease (PD) patients. Animal and human evidence showed that amantadine may also exert neuroprotection in several neurological disorders. Additionally, it is generally believed that this neuroprotection results from the ability of amantadine to inhibit glutamatergic NMDA receptor. However, several lines of evidence questioned the neuroprotective capacity of NMDA receptor antagonists in animal models of PD. Thus the cellular and molecular mechanism of neuroprotection of amantadine remains unclear. Using primary cultures with different composition of neurons, microglia, and astroglia we investigated the direct role of these glial cell types in the neuroprotective effect of amantadine. First, amantadine protected rat midbrain cultures from either MPP⁺ or lipopolysaccharide (LPS), two toxins commonly used as PD models. Second, our studies revealed that amantadine reduced both LPS- and MPP⁺-induced toxicity of dopamine neurons through 1) the inhibition of the release of microglial pro-inflammatory factors, 2) an increase in expression of neurotrophic factors such as GDNF from astroglia. Lastly, differently from the general view on amantadine’s action, we provided evidence suggesting that NMDA receptor inhibition was not crucial for the neuroprotective effect of amantadine. In conclusion, we report that amantadine protected dopamine neurons in two PD models through a novel dual mechanism, namely reducing the release of pro-inflammatory factors from activated microglia and increasing the expression of GNDF in astroglia.     

KR-25018: A novel,orally active analgesic with non-narcotic properties

Among the new series of phenylacetamides, one of capsaicin derivatives, KR-25018 was found to have a very potent analgesic activity. Thus, the pharmacological properties of KR-25018 were compared with those of morphine, capsaicin, and nonsteroidal antiinflammatory drugs (NSAIDs). The analgesic activities were evaluated in several animal models, using different stimuli, such as phenylbenzoquinone(PBQ)-induced writhing test, tail-flick test in mice and adjuvant arthritic flexion test in rat. The relationship of pharmacological properties of KR-25018 to that of centrally acting opioids was assessed by the blocking test using naloxone. The analgesic potency of the KR-25018 (MPED₅₀=0.89 p.o. in PBQ-induced writhing test, MPED₅₀ =0.61 s.c. in tail-flick test in mice), with different action mechanism from morphine and NSAIDs, was comparable to that of morphine.     

The role of TLR4/NF-κB signaling pathway in activated microglia of rats with chronic high intraocular pressure and vitro scratch injury-induced microglia

Glaucoma is a kind of blind-causing disease with structural damages of optic nerve and defection of visual field. It is believed that the death of retinal ganglion cell (RGC) is a consequential event of over-reactive immune orchestral cells such as microglia. Previous evidences in animal and clinical studies show the innate immunity plays a pivotal role in neuro-inflammation of glaucoma. Toll-like receptor 4 (TLR4) is expressed on microglia and mediates many neuroinflammatory diseases. We aimed to explore the impacts of high intraocular pressure (IOP) on rat microglia in retina and the regulation of TLR4/NF-κB signaling pathway in scratched microglia cells. In our study, we successfully established chronic high IOP rat model by episcleral vein cauterization (EVC) which behaved like the chronic glaucoma. Besides, we set up an in vitro scratch-induced injury model in rat microglia cells. We found the level of activated microglia cells were significantly increased in the retina of chronic high IOP groups. Moreover, the inhibition of TLR4/NF-κB signaling pathway suppressed the expression of TLR4 protein and mRNA levels of P50, IL-6 and TNF-α. Our original study provided a theoretical basis on targeting TLR4/NF-κB to suppress pro-inflammatory factors releasing in activated microglia and it might be a good treatment target to prevent glaucoma from progressing.     

Tissue transglutaminase: a novel pharmacological target in preventing toxic protein aggregation in neurodegenerative diseases

Alzheimer's disease, Parkinson's disease and Huntington's disease are neurodegenerative diseases, characterized by the accumulation and deposition of neurotoxic protein aggregates. The capacity of specific proteins to self-interact and form neurotoxic aggregates seems to be a common underlying mechanism leading to pathology in these neurodegenerative diseases. This process might be initiated and/or accelerated by proteins that interact with these aggregating proteins. The transglutaminase (TG) family of proteins are calcium-dependent enzymes that catalyze the formation of covalent ε-(γ-glutamyl)lysine isopeptide bonds, which can result in both intra- and intermolecular cross-links. Intramolecular cross-links might modify self-interacting proteins, and make them more prone to aggregate. In addition, intermolecular cross-links could link self-aggregating proteins and thereby initiate and/or stimulate the aggregation process. So far, increased levels and activity of tissue transglutaminase (tTG), the best characterized member of the TG family, have been observed in many neurodegenerative diseases, and the self-interacting proteins, characteristic of Alzheimer's disease, Parkinson's disease and Huntington's disease, are known substrates of tTG. Here, we focus on the role of tTG in the initiation of the aggregation process of self-interacting proteins in these diseases, and promote the notion that tTG might be an attractive novel target for treatment of neurodegenerative diseases.     

Matrix Metalloproteinases,New Insights into the Understanding of Neurodegenerative Disorders

Matrix metalloproteinases (MMPs) are a subfamily of zinc-dependent proteases that are responsible for degradation and remodeling of extracellular matrix proteins. The activity of MMPs is tightly regulated at several levels including cleavage of prodomain, allosteric activation, compartmentalization and complex formation with tissue inhibitor of metalloproteinases (TIMPs). In the central nervous system (CNS), MMPs play a wide variety of roles ranging from brain development, synaptic plasticity and repair after injury to the pathogenesis of various brain disorders. Following general discussion on the domain structure and the regulation of activity of MMPs, we emphasize their implication in various brain disorder conditions such as Alzheimer’s disease, multiple sclerosis, ischemia/reperfusion and Parkinson’s disease. We further highlight accumulating evidence that MMPs might be the culprit in Parkinson’s disease (PD). Among them, MMP-3 appears to be involved in a range of pathogenesis processes in PD including neuroinflammation, apoptosis and degradation of α-synuclein and DJ-1. MMP inhibitors could represent potential novel therapeutic strategies for treatments of neurodegenerative diseases.     

Protecting the Synapse: Evidence for a Rational Strategy to Treat HIV-1 Associated Neurologic Disease

Loss of synaptic integrity and function appears to underlie neurologic deficits in patients with HIV-1-associated dementia (HAD) and other chronic neurodegenerative diseases. Because synaptic injury often long precedes neuronal death and surviving neurons possess a remarkable capacity for synaptic repair and functional recovery, we hypothesize that therapeutic intervention to protect synapses has great potential to improve neurologic function in HAD and other diseases. We discuss findings from both HAD and Alzheimer's disease to demonstrate that the disruption of synaptic structure and function that can occur during excitotoxic injury and neuroinflammation represents a likely substrate for neurologic deficits. Based on available evidence, we provide a rationale for future studies aimed at identifying molecular targets for synaptic protection in neurodegenerative disease. Whereas patients with HAD beginning antiretroviral therapy have shown reversal of neurologic symptoms that is unique for patients with chronic neurodegenerative conditions, we propose that the potential for such reversal is not unique.     

新型查尔酮类化合物TPY的抗氧化及抗菌活性研究

目的 研究查尔酮类化合物TPY的抗氧化、抗菌活性.方法 测定TPY对DPPH·清除能力和总还原能力,测定TPY对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、沙门氏菌和变形杆菌等菌种的体外抑菌作用.结果 TPY的抗氧化能力呈现出明显的剂量依赖关系,具有良好的抗氧化活性.TPY对5种病菌具有不同程度的抑制作用.结论 TPY可作为一种理想的抗氧化和抑菌添加剂.     

新型有机硒类抗肿瘤化合物WB硒啉在体内组织分布研究(英文)

本研究首次对新型有机硒类抗肿瘤化合物1,2-[bis(1,2-benzisoselenazolone-3(2H)-ketone)]pentane(WB)进行组织分布特点研究。将H22荷瘤小鼠单次和连续多次灌胃给药WB(120 mg/kg/d)4小时后,用氢化物发生原子荧光光谱法(AFS)测定组织、血浆、肿瘤中的硒含量,考察WB的组织分布特点。经测定发现肝脏和胃肠道的硒含量显著升高,心、脾、肺、胰、血浆、肿瘤的硒含量也有不同程度的升高,脑和肾的硒含量基本无变化,两种给药方式引起的各组织硒含量变化无显著性差异。结果表明:WB及其代谢物在肝和胃肠道有靶向摄入,在其他器官也有不同程度的摄入,但WB无明显蓄积表现。     

A novel compound from Hedysarum polybotrys

A polyhydroxyl constituent (1), named as polybotrin, along with two known compounds, were isolated from the roots of Hedysarum polybotrys. Their structures were identified based on chemical and spectroscopic evidence.     

T-817MA,a novel neurotrophic compound,ameliorates phencyclidine-induced disruption of sensorimotor gating

Rationale Neurodegenerative changes have been suggested to provide a basis for the pathophysiology of schizophrenia. T-817MA (1-{3-[2-(1-benzothiophen-5-yl) ethoxy] propyl} azetidin-3-ol maleate) is a novel compound with neuroprotective and neurite-outgrowth effects, as elicited in rat primary cultured neurons. Objectives We examined the effect of T-817MA on phencyclidine (PCP)-induced disruption of prepulse inhibition (PPI), a measure of sensorimotor gating, in male Wistar rats. Materials and methods In chronic experiments, male Wistar rats were injected intermittently with PCP (2.0 mg/kg, i.p., three times per week) or vehicle (saline, 2.0 ml/kg) for 1 month. T-817MA (0.21 or 0.07 mg/ml, p.o.) or distilled water was administered throughout the study period. In an acute experiment, T-817MA (8.4 mg/kg, p.o.) or distilled water was administered, followed by treatment with PCP (2.0 mg/kg, i.p.) or vehicle (saline, 2.0 ml/kg), before PPI measurements. Results Intermittent administration of PCP for 1 month induced persistent disruption of PPI. Coadministration of T-817MA at 0.21 mg/ml but not 0.07 mg/ml completely blocked PCP-induced disruption of PPI, whereas T-817MA (0.21 mg/ml) by itself did not show a significant effect on PPI in control rats. On the other hand, single administration of T-817MA did not affect PPI disruption by acute treatment with PCP. Conclusions These results suggest that T-817MA is effective in ameliorating sensorimotor gating deficits caused by chronic PCP treatment, possibly via neuroprotective actions. Our findings provide a novel therapeutic approach for patients with schizophrenia.     

A novel phenolic compound from Pinus yunnanensis

A rare type of phenolic compound, namely, planchol E (1), was isolated from the cones and seeds of Pinus yunnanensis together with 16 known abietane diterpenoids (2–17). The structure of planchol E was established on the basis of extensive spectroscopic analysis, and it was found that the new compound did not show cytotoxic activity against several cancer cell lines.     

A novel berberine‐metformin hybrid compound exerts therapeutic effects on obese type 2 diabetic rats

In this study, we investigated the biological activities of a novel berberine‐metformin hybrid compound (BMH473) as an anti‐diabetic agent. BMH473 exhibited significant anti‐hyperglycaemic and anti‐hyperlipidaemic effects on T2DM rats. In white adipose tissue, BMH473 reduced the perirenal and epididymal adipose tissue mass and modulated the lesions in perirenal adipose tissue, by inhibiting the protein expressions of PPAR‐?, C/EBP‐α and SREBP‐1c as well as the mRNA expressions of lipogenic genes. Moreover, BMH473 downregulated the levels of pro‐inflammatory cytokines in perirenal adipose tissue through the suppression of p‐NF‐κB. In liver, BMH473 reduced liver ectopic fat accumulation, by regulating the protein expression levels of SREBP‐1c and PPAR‐α as well as the mRNA expression levels of lipogenic genes. In addition, BMH473 inhibited hepatic gluconeogenesis by promoting the phosphorylation levels of AMPK α and ACC, and down‐regulating the mRNA expression levels of FBPase, G6Pase and PEPCK. Furthermore, BMH473 exhibited significant inhibitory effects on lipogenesis and lipid accumulation in 3T3‐L1 adipocytes by modulating the protein expression levels of PPAR‐?, C/EBP‐α and SREBP‐1 c as well as the mRNA expression levels of lipogenic genes. In conclusion, our results suggest that the newly synthesized BMH473 is beneficial for maintaining glucose and lipid homeostasis in type 2 diabetic rats, and exhibits better anti‐hyperlipidaemic effects compared to metformin and berberine.     

复方银杏叶口服液的制备与临床观察

目的：配制复方银杏叶口服液并观察其临床疗效。方法：以银杏叶提取物、人参浸膏、五味子提取物等组方制成复方银杏叶口服液，高效液相色谱法测定银杏总黄酮醇苷；选择174例冠心病患者，采取随机方法分为治疗组（复方银杏叶口服液组）84例，对照组（银杏叶口服液组）90例。结果：本品1mL含银杏总黄酮醇苷不得少于3．6mg；治疗两周后，治疗组与对照组总有效率分别为97．62％和81．11％（P〈0．05）。结论：复方银杏叶口服液配方合理、制备工艺简单易行、质量可控；加用复方银杏叶口服液治疗冠心病疗效明显优于加用银杏叶口服液。