The Anti-Atopic Dermatitis Effects of Mentha arvensis Essential Oil Are Involved in the Inhibition of the NLRP3 Inflammasome in DNCB-Challenged Atopic Dermatitis BALB/c Mice.

The NLRP3 inflammasome is upregulated by various agents, such as nuclear factor-kappa B (NF-κB), lipopolysaccharide (LPS), and adenosine triphosphate (ATP). The NLRP3 inflammasome facilitations the maturation of interleukin (IL)-1ß, a proinflammatory cytokine that is critically involved in the pathogenesis of atopic dermatitis (AD). Although the NLRP3 inflammasome clearly exacerbates AD symptoms such as erythema and pruritus, drugs for AD patients targeting the NLRP3 inflammasome are still lacking. Based on the previous findings that Mentha arvensis essential oil (MAEO) possesses strong anti-inflammatory and anti-AD properties through its inhibition of the ERK/NF-κB signaling pathway, we postulated that MAEO might be capable of modulating the NLRP3 inflammasome in AD. The aim of this research was to investigate whether MAEO affects the inhibition of NLRP3 inflammasome activation in murine bone marrow-derived macrophages (BMDMs) stimulated with LPS + ATP in vitro and in a murine model displaying AD-like symptoms induced by 2,4-dinitrochlorobenzene (DNCB) in vivo. We found that MAEO inhibited the expression of NLRP3 and caspase-1, leading to the suppression of NLRP3 inflammasome activation and IL-1ß production in BMDMs stimulated with LPS + ATP. In addition, MAEO exhibited efficacy in ameliorating AD symptoms in a murine model induced by DNCB, as indicated by the reduction in dermatitis score, ear thickness, transepidermal water loss (TEWL), epidermal thickness, and immunoglobulin E (IgE) levels. Furthermore, MAEO attenuated the recruitment of NLRP3-expressing macrophages and NLRP3 inflammasome activation in murine dorsal skin lesions induced by DNCB. Overall, we provide evidence for the anti-AD effects of MAEO via inhibition of NLRP3 inflammasome activation.

S1P1 Regulates M1/M2 Polarization toward Brain Injury after Transient Focal Cerebral Ischemia.

M1/M2 polarization of immune cells including microglia has been well characterized. It mediates detrimental or beneficial roles in neuroinflammatory disorders including cerebral ischemia. We have previously found that sphingosine 1-phospate receptor subtype 1 (S1P1) in post-ischemic brain following transient middle cerebral artery occlusion (tMCAO) can trigger microglial activation, leading to brain damage. Although the link between S1P1 and microglial activation as a pathogenesis in cerebral ischemia had been clearly demonstrated, whether the pathogenic role of S1P1 is associated with its regulation of M1/M2 polarization remains unclear. Thus, this study aimed to determine whether S1P1 was associated with regulation of M1/M2 polarization in post-ischemic brain. Suppressing S1P1 activity with its functional antagonist, AUY954 (5 mg/kg, p.o.), attenuated mRNA upregulation of M1 polarization markers in post-ischemic brain at 1 day and 3 days after tMCAO challenge. Similarly, suppressing S1P1 activity with AUY954 administration inhibited M1-polarizatioin-relevant NF-κB activation in post-ischemic brain. Particularly, NF-κB activation was observed in activated microglia of post-ischemic brain and markedly attenuated by AUY954, indicating that M1 polarization through S1P1 in post-ischemic brain mainly occurred in activated microglia. Suppressing S1P1 activity with AUY954 also increased mRNA expression levels of M2 polarization markers in post-ischemic brain, further indicating that S1P1 could also influence M2 polarization in post-ischemic brain. Finally, suppressing S1P1 activity decreased phosphorylation of M1-relevant ERK1/2, p38, and JNK MAPKs, but increased phosphorylation of M2-relevant Akt, all of which were downstream pathways following S1P1 activation. Overall, these results revealed S1P1-regulated M1/M2 polarization toward brain damage as a pathogenesis of cerebral ischemia.

Drosophila melanogaster Parkin ubiquitinates peanut and septin1 as an E3 ubiquitin-protein ligase.

Autosomal recessive juvenile parkinsonism (AR-JP), a common familial form of Parkinson's disease, is caused by mutations of human Parkin. To deepen the understanding of Parkin biology in an in vivo model of Drosophila, we attempted to characterize the function of Drosophila melanogaster Parkin and found that D. melanogaster Parkin exhibited UbcH8-dependent E3 ubiquitin-protein ligase activity. Using E2 binding and in vitro ubiquitination assays, UbcH8 preferentially was found to bind to Parkin mutants harboring functional RING1 domains, but failed to bind to mutants harboring point mutants with complete loss of function. This inability of UbcH8 binding to such mutants was accompanied by abrogation of an E3 ligase activity, indicating that D. melanogaster Parkin as an E3 ligase interacts with UbcH8 through its RING1 domain. An in vivo ubiquitination assay revealed that D. melanogaster Parkin existed in ubiquitinated form in vivo. Moreover, peanut and septin1, D. melanogaster septin proteins, were also ubiquitinated by D. melanogaster Parkin. Co-immunoprecipitation with membrane protein Syntaxin indicated direct binding of septin proteins to syntaxin, implicating their relevance in the exocytosis of dopamine in cells. Western blot analysis and DNA fragmentation indicated that the rate and efficiency of p53-dependent apoptosis were significantly higher in the presence of dopamine than without the septin proteins. Therefore, our findings in the present study demonstrate that Parkin possibly influences septin protein effects on p53-mediated apoptosis, helping to extend the utility of Drosophila as a model system for the study of neurodegeneration.

Genomic organization and expression of parkin in Drosophila melanogaster.

We report here the isolation, characterization on genomic structure and expression of the D. melanogaster homolog of human parkin. The 2,122 bp parkin gene sequence contains six exons that form a 1,449 bp transcript encoding a protein of 482 amino acids. 151 bp of 5' and 112 bp of 3' untranslated regions were identified by a combination of 5'-RACE/primer extension and 3'-RACE, respectively. The 5' UTR contains three transcription initiation sites. Neither a classical TATA nor a CAAT box was found in the putative promoter sequence. However, binding sites for AhR-Arnt, AP4, NF1 and GATA transcription factors were identified. Transient transfection analysis of the 5' UTR confirmed its promoter activity in HEK 293 cells and SH-SY5Y neuronal cells using a dual luciferase reporting system. The amino acid sequence of D. melanogaster Parkin exhibits 42%, 43% and 43% identity to that of human, mouse and rat, respectively, representing a 54 kDa protein band via western blot analysis. It shows a high degree of conservation in the Ubiquitin-like domain at the N-terminus (34%), the In-Between RING finger domains (IBR, 65-69%), and the RING finger domains at the C-terminus (56-57%). The expression pattern of D. melanogaster parkin varies during the developmental stages, with the highest expression in the adult stage as measured by competitive RT-PCR. From immunostainings of the embryo, D. melanogaster parkin was expressed slightly higher in the central nervous system (brain and nerve cord) during the late embryonic stage.

[The protective factors of suicide probability in religious male high school students].

PURPOSE: This study was conducted to identify the protective factors that influence suicide probability in religious male high school students. METHODS: The data was collected from Nov. 5 to Dec. 10, 2009. Data were collected by self-report questionnaire from 255 students selected from 2 religious male high schools in B city. The instruments for this study were the Suicide Probability Scale for Adolescence (SPS-A), Inventory Parents Peer Attachment-Revision (IPPA-R), Spiritual Well-being Scale (SWBS), and Ego-identity Scale. The data were analyzed using t-test, one-way ANOVA, Scheffe test, Pearson correlation coefficients and stepwise multiple regression with the SPSS 14.0 program. RESULTS: The protective factors of suicide probability in religious male high school students were identified as existential spiritual well-being (ß= -.46, p<.001), self-identity (ß= -.30, p<.001), and mother attachment (ß= -.21, p<.001). These three factors explained 61.5% of the variance in suicide probability. CONCLUSIONS: The results suggest that improvement in spirituality, ego-identity, and mother attachment for religious male high school students is important to reduce the probability of suicide.