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Lipopolysaccharides released during bacterial infections induce the expression of pro-inflammatory cytokines and lead to complications such as neuronal damage in the CNS and septic shock in the periphery. While the initial infection is treated by antibiotics, anti-inflammatory agents would be advantageous add-on medications. In order to identify such compounds, we have compared 29 commercially available polyphenol-containing plant extracts and pure compounds for their ability to prevent LPS-induced up-regulation of NO production. Among the botanical extracts, bearberry and grape seed were the most active preparations, exhibiting IC(50) values of around 20 mug/mL. Among the pure compounds, IC(50) values for apigenin, diosmetin and silybin were 15, 19 and 12 muM, in N-11 murine microglia, and 7, 16 and 25 muM, in RAW 264.7 murine macrophages, respectively. In addition, these flavonoids were also able to down-regulate LPS-induced tumour necrosis factor production. Structure-activity relationships of the flavonoids demonstrated three distinct principles: (i) flavonoid-aglycons are more potent than the corresponding glycosides, (ii) flavonoids with a 4'-OH substitution in the B-ring are more potent than those with a 3'-OH-4'-methoxy substitution, (iii) flavonoids of the flavone type (with a C2=C3 double bond) are more potent than those of the flavanone type (with a at C2-C3 single bond).

Alzheimer's disease is the most common cause of dementia in the elderly population. The most widely used treatment for Alzheimer's disease at present is acetylcholinesterase inhibitors, which aim to prolong cognitive function through increased synaptic activity, without providing neuroprotection. This treatment is only symptomatic and provides modest outcomes for patients. The recent elucidation of the inflammatory pathways involved in Alzheimer's disease however, has opened doors for better treatment and prevention by identification of areas of therapeutic intervention that target the cause of the disease rather than the symptoms. This review describes the inflammatory pathways that are thought to be present in Alzheimer's disease and some of the new therapies that have shown promise, via alteration or inhibition of these pathways. Some of the therapies included in this review, which have already demonstrated beneficial effects in the treatment of Alzheimer's disease, or have the potential to do so, are nonsteroidal anti-inflammatory drugs, statins, RAGE antagonists and antioxidants.

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Transfection of mammalian cell lines is a widely used technique that requires significant optimization, including transfection method or product used, DNA vector, cell density, media composition and incubation time. Generation and isolation of stable transfectants from the large pool of untransfected or only transiently transfected cells can be laborious and time-consuming. Transfection of DNA is usually performed with a non-linearized plasmid, since it is assumed that cutting the plasmid beforehand leads to a lower efficiency of transfection or the degradation of linearized DNA by cytosolic nucleases. However, the transfected circular plasmid will be linearized by a random cut within the cell and it might be possible that sensitive parts of the plasmid such as the resistance gene or the gene of interest are destroyed upon linearization. On the other hand, linearizing a plasmid before transfection by a single, defined cut with a selected restriction enzyme in a non-coding area of the gene has the advantage of ensuring the integrity of all necessary gene elements of the plasmid. In this study, we have compared these different methods in order to increase both transient and stable transfection efficiency in mammalian cells. We report that linearization of plasmid DNA prior to transfection can increase both the efficiency of stable clone generation and target gene expression, but is dependant on the site of linearization within the vector.

In many chronic neurodegenerative diseases including Frontotemporal Dementia and Alzheimer's disease (AD), microglial activation is suggested to be involved in pathogenesis or disease progression. Activated microglia secrete a variety of cytokines, including interleukin-1beta, interleukin-6, and tumor necrosis factor as well as reactive oxygen and nitrogen species (ROS/RNS). ROS and RNS contribute to alterations in neuronal glucose uptake, inhibition of mitochondrial enzymes, a decrease in mitochondrial membrane potential, impaired axonal transport, and synaptic signaling. In addition, ROS act as signaling molecules in pro-inflammatory redox-active signal transduction pathways. To establish a high throughput screening system for anti-inflammatory and neuroprotective compounds, we have constructed an "Enhanced Green Fluorescent protein" (EGFP) expressing neuronal cell line and set up a murine microglia/neuron co-culture system with these EGFP expressing neuronal cells. We show that microglia activation leads to neuronal cell death, which can be conveniently measured by loss of neuronal EGFP fluorescence. Moreover, we used this system to test selected polyphenolic compounds for their ability to downregulate inflammatory markers and to protect neurons against microglial insult. We suggest that this system might allow accelerated drug discovery for the treatment of inflammation-mediated neurodegenerative diseases.