Key role of MIF-related neuroinflammation in neurodegeneration and cognitive impairment in Alzheimer's disease.

BACKGROUND: Macrophage Migration Inhibitory Factor (MIF) is a potent proinflammatory cytokine that promotes the production of other immune mediators. MIF is produced by most cell types in the brain including microglia, astrocytes and neurons. Enhanced expression of MIF might contribute to the persistent activation of glial, chronic neuroinflammation and neurodegeneration. Here, we investigated the effect of MIF on inflammatory markers and spatial learning in a mouse model of sporadic AD and on tau pathology in AD patients. METHODS: We examined the effects of MIF deficiency and pharmacological MIF inhibition in vitro and in vivo. In vitro, quantitative PCR and ELISA were used to assess cytokine production of STZ-treated glial cells. In vivo, C57BL/6 mice were subjected to intracerebroventricular streptozotocin injection (3 mg/kg, ICV-STZ). Neuroinflammation and contextual learning performance were assessed using quantitative PCR and fear conditioning, respectively. Pharmacological MIF inhibition was achieved with intraperitoneal injections of ISO-1 (daily, IP, 20 mg/kg in 5% DMSO in 0.9% NaCl) for 4 weeks following ICV-STZ injection. The findings from ISO-1 treated mice were confirmed in MIF knockout C57BL/6. To assess the role of MIF in human AD, cerebrospinal fluid levels of MIF and hyperphosphorylated tau were measured using ELISA. RESULTS: Administration ICV-STZ resulted in hippocampal dependent cognitive impairment. MIF inhibition with ISO-1 significantly improved the STZ-induced impairment in contextual memory performance, indicating MIF-related inflammation as a major contributor to ICV-STZ-induced memory deficits. Furthermore, inhibition of the MIF resulted in reduced cytokine production in vitro and in vivo. In human subjects with AD at early clinical stages, cerebrospinal fluid levels of MIF were increased in comparison with age-matched controls, and correlated with biomarkers of tau hyper-phosphorylation and neuronal injury hinting at MIF levels as a potential biomarker for early-stage AD. CONCLUSIONS: The present study indicates the key role of MIF in controlling the chronic cytokine release in neuroinflammation related to tau hyperphosphorylation, neurodegeneration, and clinical manifestations of AD, suggesting the potential of MIF inhibition as therapeutic strategy to slow down neurodegeneration and clinical disease progression.

Influence of Mechanical Skin Treatments on Dermal Penetration Efficacy of Active Ingredients.

The effective dermal penetration of active ingredients (AI) is a major task in the formulation of topical products. Besides the vehicle, the mechanical skin treatments are also considered to impact the penetration efficacy of AI. In particular, professional skin treatments, i.e., professional cosmetic skin treatments, are considered to be optimal for the dermal delivery of AI. However, a systematic study that proves these theories is not yet available and was therefore performed in this study while utilizing an ex vivo porcine ear model with subsequent digital image analysis. Hydrophilic and lipophilic fluorescent dyes were used as AI surrogates and were applied onto the skin without and with professional skin treatments. The skin hydration and the penetration efficacy were determined, respectively. Results showed that professional skin treatments with massage were able to increase the skin hydration, whereas a professional skin treatment without massage could not increase the skin hydration when compared to skin without professional skin treatment. Regarding the penetration efficacy, it was found that all parameters tested, i.e., type of professional skin treatment, lipophilicity of the AI, and the time point at which the AI are applied onto the skin, can have a tremendous impact on the penetration efficacy of the AI. The most effective penetration and the most effective skin hydration is achieved with a professional skin treatment that includes a professional skin massage. This kind of skin treatment can therefore be used to improve dermal drug delivery.

Assessing the Dermal Penetration Efficacy of Chemical Compounds with the Ex-Vivo Porcine Ear Model.

(1) Background: The ex vivo porcine ear model is often used for the determination of the dermal penetration efficacy of chemical compounds. This study investigated the influence of the post-slaughter storage time of porcine ears on the dermal penetration efficacy of chemical compounds. (2) Methods: Six different formulations (curcumin and different fluorescent dyes in different vehicles and/or nanocarriers) were tested on ears that were (i) freshly obtained, (ii) stored for 24 or 48 h at 4 °C after slaughter before use and (iii) freshly frozen and defrosted 12 h before use. (3) Results: Results showed that porcine ears undergo post-mortem changes. The changes can be linked to rigor mortis and all other well-described phenomena that occur with carcasses after slaughter. The post-mortem changes modify the skin properties of the ears and affect the penetration efficacy. The onset of rigor mortis causes a decrease in the water-holding capacity of the ears, which leads to reduced penetration of chemical compounds. The water-holding capacity increases once the rigor is released and results in an increased penetration efficacy for chemical compounds. Despite different absolute penetration values, no differences in the ranking of penetration efficacies between the different formulations were observed between the differently aged ears. (4) Conclusions: All different types of ears can be regarded to be suitable for dermal penetration testing of chemical compounds. The transepidermal water loss (TEWL) and/or skin hydration of the ears were not correlated with the ex vivo penetration efficacy because both an impaired skin barrier and rigor mortis cause elevated skin hydration and TEWL values but an opposite penetration efficacy. Other additional values (for example, pH and/or autofluorescence of the skin) should, therefore, be used to select suitable and non-suitable skin areas for ex vivo penetration testing. Finally, data from this study confirmed that smartFilms and nanostructured lipid carriers (NLC) represent superior formulation strategies for efficient dermal and transdermal delivery of curcumin.

Nanocrystals for improved dermal drug delivery.

Nanocrystals are composed of 100% active and possess an increased aqueous solubility and dissolution velocity when compared to larger sized materials. Nanocrystals can be used to improve the bioavailability of poorly soluble actives not only for oral, but also for topical application. In this study nanocrystals of different sizes were produced and the influence of size on dermal penetration was investigated. The influence of different excipients and vehicles on the penetration efficacy upon dermal application was also investigated. Results confirm that dermal penetration of poorly soluble actives increases with decreasing size of the nanocrystals. Unexpectedly, it was observed that many classical penetration enhancers failed to promote the penetration of actives from nanocrystals. Also hydrogels were found to be non-suitable vehicles for the formulation of nanocrystals. As most suitable vehicles for nanocrystals oleogels and creams were identified.

Association study of mitochondrial genetic polymorphisms in asthmatic children.

It has been suggested that mitochondrial dysfunction plays a role in the pathogenesis of asthma. To test whether mitochondrial variants influence the risk of asthma, we analyzed 16,158 mtSNPs in a sample of 372 asthmatic children and 395 healthy children using the DNA pooling technique and genome wide association analysis. Stratified analysis by sex was performed to explain the differences observed between sexes in the etiology of asthma. Different variants were detected to be significant in the sample of girls and boys with the smallest adjusted p values being 1.4 × 10(-09) (mt5295) and 3.6 × 10(-12) (mt16158), respectively. Most of the significant locations found in boys are within the CYB gene and the non-coding region. For girls, most of the significant mtSNPs lie within NADH-dehydrogenase-subunits. The variants reported here have not previously been described in connection with asthma. Although further studies in other cohorts are needed to confirm these findings our study highlights the importance of the mitochondria among the factors that contribute to the risk of asthma.

Exogenous supply of glutamine and active cytokinin to the roots reduces NO3- uptake rates in poplar.

The present study shows for the first time the influence of exogenously applied amino acids and cytokinin on the physiological and molecular aspects of N metabolism in poplar trees. In a short-term feeding experiment, glutamine or trans-zeatin riboside (tZR) was added directly to the nutrient solution. NO3- net uptake declined significantly in response to both treatments. Feeding with glutamine brought about an increase in concentrations of different amino compounds in the roots (glutamine, glutamate, alanine, gamma-amino butyric acid (GABA) and NH4+, which negatively correlated with the net NO3- uptake. The plants showed a reduction of cytosolic glutamine synthetase 1 (GS1) transcript level in the roots. In addition, glutamine feeding changed the root-to-shoot distribution on N assimilation in favour of the leaves and plant internal N cycling. tZR treatment resulted in expansion of zeatin-type (Z-type) cytokinins in the roots and increased nitrate reductase (NR)-mRNA level. The results indicate that both particular amino acids and active cytokinins are involved in the feedback regulation of N uptake and metabolism in poplar. We propose that inhibition of N uptake by cytokinins in poplar is more complex than that mediated by amino compounds, and other effectors are involved in this regulation.

Association of uteroglobulin-related protein 1 with bronchial asthma.

BACKGROUND: Chromosomal region 5q31 harbours a number of genes associated with atopic phenotypes, for example the genes coding for interleukin (IL) 4, IL13 and the beta(2)-adrenoreceptor. A new gene within this region was identified only very recently. The encoded protein - uteroglobin-related protein 1 (UGRP1) - is thought to act as an anti-inflammatory agent and is mainly expressed in the lung and trachea. The functional promoter polymorphism A-112G in UGRP1 was shown to be associated with bronchial asthma in a Japanese population. We were thus interested in finding out whether the polymorphism so far identified or others within UGRP1 were associated with bronchial asthma in a German Caucasian population. METHODS: We performed direct genomic sequencing of the promoter and coding region of UGRP1 in 15 asthmatic children and 15 controls. The identified polymorphisms were genotyped by means of RFLP. Statistical analysis was performed with the Armitage trend test. RESULTS: We identified 5 non-coding variants, 4 of which being described for the first time. Three polymorphisms were common and typed in 182 asthmatic children and 270 controls. None of the polymorphisms were associated with bronchial asthma in our population. CONCLUSIONS: We conclude from our data that UGRP1 does not play a major role in the development of bronchial asthma in our Caucasian population.

Multilocus haplotype analyses reveal association between 5 novel IL-15 polymorphisms and asthma.

BACKGROUND: IL-15 is a T(H)1-related cytokine that is involved in the inflammatory response in various infectious and autoimmune diseases. IL-15 has recently been shown to be upregulated in T-cell-mediated inflammatory disorders. The observations suggest a potential role for this cytokine in a variety of pathologic conditions, including T(H)1-mediated and T(H)2-mediated inflammatory diseases. OBJECTIVE: In this study, we searched for single nucleotide polymorphisms in the whole IL-15 gene and investigated their association with inflammatory and/or atopic phenotypes. METHODS: The screening for single nucleotide polymorphisms was performed by single-strand conformation polymorphism analysis. Genotyping of the identified polymorphisms was performed by restriction fragment length polymorphism. Genotypic association analysis used the Armitage trend test. Haplotype frequency estimation and subsequent testing for differences between cases and controls were performed by using the programs FASTEHPLUS and FAMHAP. RESULTS: We identified 5 novel noncoding nucleotide sequence variants, all of which were typed in our asthmatic, our atopic, and our control population. According to the Armitage trend test, none of the 5 polymorphisms is associated with the phenotype bronchial asthma or atopy. However, multilocus haplotype analysis based on simulations to find out whether the haplotype frequencies differed between cases and controls by using the program FAMHAP yielded a P value of 6.1 x 10(-5) in the asthmatic versus the control population, which is highly significant. Furthermore, we obtained a nominally significant result of P=.0232 for the atopic versus the control population by using FAMHAP. CONCLUSION: These results strongly underscore previous findings that suggest a potential role of this cytokine in allergic diseases.