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Alzheimer's disease (AD) is a progressive neurodegenerative disorder associated with synaptic dysfunction, pathological accumulation of β-amyloid peptide 1-42 (Aβ1-42 ), and neuronal loss. The self-association of Aβ1-42 monomers (Aβ-M) into soluble oligomers seems to be crucial for the development of neurotoxicity. Previous publications have shown that Aβ oligomers and dimers might play key roles in inducing AD. The role of Aβ-M was rarely investigated and still unclear in AD. To understand the effects of Aβ-M on neurons and other cell types in the brain could be the key to understand its function. In our study, we found that Aβ-M expression slowly induced cell apoptosis within 48 hours after transfection, β2 adrenergic receptor (β2AR) interacted with Aβ-M in the pull-down and the yeast two-hybrid assays, and Aβ-M played a major role in inducing phosphorylation of Tau at Ser-214, c-Jun N-terminal kinase (JNK) at Thr-183/Tyr-185, p70 ribosomal protein S6 kinase (p70S6K) at Thr-389. We also discovered that β2AR, G protein-coupled receptor kinase 2 (GRK2), and protein kinase A (PKA) mediated the phosphorylation of Tau and JNK. Aβ-M induced phosphorylation of Tau at Ser-214 through both β2AR-cAMP/PKA-JNK and β2AR-GRK signaling pathways. Mitogen-activated protein kinase kinase (MEK) mediated the phosphorylation of p70S6K induced by Aβ-M.

Keap1 is deemed as a suppressor of Nrf2 in cytoplasm by sequestrating Nrf2 to proteolysis as an adapter of the Cul3-Rbx1 E3 ubiquitin ligase complex. In the study, it was proposed that post-translational modification might affect the interaction between Nrf2 and Keap1, and the profiles of the phosphorylation of amino acid residues of Keap1 and its effects on the binding of Keap1 to Nrf2 was investigated. A mass spectrometry analysis revealed that S53 and S293 were phosphorylated upon an oxidative stress. Using Keap1 proteins with amino acid residues mutated to glutamate to simulate the introduction of a negative charge by phosphorylation, it was found that a potential phosphorylation of S53 affected Keap1-Nrf2 binding in the pull-down assay, and induced nuclear translocation of Nrf2 in the electrophoretic mobility shift assay. Sequence homology analysis showed that S53 was highly conserved. Structural modeling around BTB domain of wild type and S53E-mutant Keap1 showed that the negative charge introduced by S53E mutation generates a salt bridge between E53 and ionized guanidine group of Arg50. Real-time qRT-PCR for transcription levels of antioxidant genes that are modulated by Nrf2 further proved the effects of the potential phosphorylation of S53 under an oxidative stress condition. In summary, S53 is a potential phosphorylation site of Keap1, and the phosphorylation could enhance the antioxidative capacity of cells in response to an oxidative stress.

Alzheimer's disease (AD) is a lifelong progressive neurodegenerativa disease related with accumulation of amyloid β peptide (Aβ) produced by processing of amyloid precursor protein (APP) in the brain. In spite of several-decades effort on AD, there is still no medicine used to intervene with its pathological processes. Our previous studies made in transgenic animal models harboring familial AD genes of mutant presenilin 1 and amyloid precursor protein (APP) showed that β2AR gene knock-out (β2AR-KO) is beneficial in senile AD animals. Consistently, an epidemiological study lasted for two decades showed that the sole usage of β blockers as antihypertensive medicines is associated with fewer brain lesions and less brain shrinkage seen in senile AD patients. In order to understand why senile β2AR-KO AD mice had better learning and memory, genomic effects of β2AR-KO in the double transgenic AD mice were investigated. In the analysis, major genomic significance of β2AR-KO was directed to influence protein-processing and presentation involving membrane structure and MHC class I and II protein complex, and lysosome and hydrolase activity for protein degradation, which are critical for accumulation of amyloid β peptide, the hallmark of AD.

Troxerutin, a semi-synthetic derivative of the natural bioflavanoid rutin, has been reported to possess many beneficial effects in human bodies, such as vasoprotection, immune support, anti-inflammation and anti-aging. However, the effects of troxerutin on genome-wide transcription in blood cells are still unknown. In order to find out effects of troxerutin on gene transcription, a high-throughput RNA sequencing was employed to analysis differential gene expression in blood cells consisting of leucocytes, erythrocytes and platelets isolated from the mice received subcutaneous injection of troxerutin. Transcriptome analysis demonstrated that the expression of only fifteen genes was significantly changed by the treatment with troxerutin, among which 5 genes were up-regulated and 10 genes were down-regulated. Bioinformatic analysis of the fifteen differentially expressed genes was made by utilizing the Gene Ontology (GO), and the differential expression induced by troxerutin was further evaluated by real-time quantitative PCR (Q-PCR).

Regulatory T cells (Tregs) restrict over-exuberant lymphocyte activation. While close proximity between Tregs and their suppression targets is important for optimal inhibition, and literature indicates that draining lymph nodes may serve as a prime location for the suppression, signaling details orchestrating this event are not fully characterized. Using a protocol to enable peripheral generation of inducible antigen-specific Tregs (asTregs) to control allergen-induced asthma, we have identified an antigen-specific mechanism that locks asTregs within hilar LNs which in turn suppresses airway inflammation. The suppressive asTregs, upon antigen stimulation in the lymph node, downregulate S1p1 (Sphingosine-1-phosphate receptor 1) egress receptor expression. These asTregs in turn mediate the downregulation of the same receptor on incoming effector T cells. Therefore, asTregs and effector T cells are locked in these draining lymph nodes for prolonged interactions. Disruption of individual steps of this retention sequence abolishes the inflammation controlled by asTregs. Collectively, this study identifies a new requirement of spatial congregation with their suppression targets essential for asTreg functions, and suggests therapeutic programs via Treg traffic control.

Pet allergens are major causes for asthma and allergic rhinitis. Fel d 1 protein, a key pet allergen from domestic cat, can sensitize host and trigger asthma attack. In this study, we report that co-immunization with recombinant Fel d 1 protein (rFel d 1) plus plasmid DNA that contains Fe1 d 1 gene was effective in preventing and treating the natural Fel d 1 (nFel d 1) induced allergic airway inflammation in mice. A population of T regulatory cells (iTreg) exhibiting a CD4+CD25-Foxp3+ phenotype and expressing IL-10 and TGF-β was induced by this co-immunization strategy. Furthermore, after adoptive transfers of the iTreg cells, mice that were pre-sensitized and challenged with nFel d 1 exhibited less signs of allergic inflammation, AHR and a reduced allergic immune response. These data indicate that co-immunization with DNA and protein mixture vaccine may be an effective treatment for cat allergy.

Adrenocorticotropic hormone (ACTH) is the only medicine for treating infantile spasms, however, it is catabolized rapidly. In order to make an ACTH derivative with prolonged effects, we prepared genetically engineered wild type (WT) and mutant ACTH candidates based on protease database analysis, and compared their stability and pharmacological effects. For analysis of stability, serum concentration of WT and mutant ACTH candidates were tested at different time after intravenous injection, and elimination curves were calculated to compare pharmacokinetic properties of WT and E5D-mutant ACTH. For comparison of their pharmacological effects, levels of glucocorticoids (GC) in the blood serum and secreted from cultured Y1 mouse adrenal cells were tested, and their effects on the signaling pathway mediating the expression of genes critical for GC synthesis were analyzed. The effects of ACTHs on transcription levels of the genes involved in GC synthesis were tested by qPCR. The blood concentration of E5D ACTH is higher than the WT after injection, and E5D mutation increased the t1/2 and AUC of ACTH. Pharmacological experiments showed that the effects of E5D and Y2S mutant ACTH on the production of GC and the critical signal transduction were equivalent to those of WT. WT, E5D and Y2S ACTH also have similar effects on the transcriptional levels of the genes for GC synthesis, including STAR, P450-scc, 3β-HSD, and SF-1. The stability of E5D mutant ACTH is higher than WT ACTH. The pharmacological effects of E5D ACTH is equivalent to those of WT ACTH.