Effects of latroeggtoxin-VI on dopamine and α-synuclein in PC12 cells and the implications for Parkinson's disease

Background Parkinson's disease (PD) is characterized by death of dopaminergic neurons leading to dopamine deficiency, excessive α-synuclein facilitating Lewy body formation, etc. Latroeggtoxin-VI (LETX-VI), a proteinaceous neurotoxin discovered from the eggs of spider L. tredecimguttatus, was previously found to promote the synthesis and release of PC12 cells, showing a great potential as a drug candidate for PD. However, the relevant mechanisms have not been understood completely. The present study explored the mechanism underlying the effects of LETX-VI on dopamine and α-synuclein of PC12 cells and the implications for PD. Results After PC12 cells were treated with LETX-VI, the level of dopamine was significantly increased in a dose-dependent way within a certain range of concentrations. Further mechanism analysis showed that LETX-VI upregulated the expression of tyrosine hydroxylase (TH) and L-dopa decarboxylase to enhance the biosynthesis of dopamine, and downregulated that of monoamine oxidase B to reduce the degradation of dopamine. At the same time, LETX-VI promoted the transport and release of dopamine through modulating the abundance and/or posttranslational modification of vesicular monoamine transporter 2 (VMAT2) and dopamine transporter (DAT). While the level of dopamine was increased by LETX-VI treatment, α-synuclein content was reduced by the spider toxin. α-Synuclein overexpression significantly decreased the dopamine level and LETX-VI efficiently alleviated the inhibitory action of excessive α-synuclein on dopamine. In the MPTP-induced mouse model of PD, application of LETX-VI ameliorated parkinsonian behaviors of the mice, and reduced the magnitude of MPTP-induced α-synuclein upregulation and TH downregulation. In addition, LETX-VI displayed neuroprotective effects by inhibiting MPTP-induced decrease in the numbers of TH-positive and Nissl-stained neurons in mouse brain tissues. Conclusions All the results demonstrate that LETX-VI promotes the synthesis and release of dopamine in PC12 cells via multiple mechanisms including preventing abnormal α-synuclein accumulation, showing implications in the prevention and treatment of PD.

CRISPR-mediated base editing in mice using cytosine deaminase base editor 4

BACKGROUND: Many human genetic diseases arise from point mutations. These genetic diseases can theoretically be corrected through gene therapy. However, gene therapy in clinical application is still far from mature. Nearly half of the pathogenic single-nucleotide polymorphisms (SNPs) are caused by G:C>A:T or T:A>C:G base changes and the ideal approaches to correct these mutations are base editing. These CRISPR-Cas9-mediated base editing does not leave any footprint in genome and does not require donor DNA sequences for homologous recombination. These base editing methods have been successfully applied to cultured mammalian cells with high precision and efficiency, but BE4 has not been confirmed in mice. Animal models are important for dissecting pathogenic mechanism of human genetic diseases and testing of base correction efficacy in vivo. Cytidine base editor BE4 is a newly developed version of cytidine base editing system that converts cytidine (C) to uridine (U). RESULTS: In this study, BE4 system was tested in cells to inactivate GFP gene and in mice to introduce single-base substitution that would lead to a stop codon in tyrosinase gene. High percentage albino coat-colored mice were obtained from black coat-colored donor zygotes after pronuclei microinjection. Sequencing results showed that expected base changes were obtained with high precision and efficiency (56.25%). There are no off-targeting events identified in predicted potential off-target sites. CONCLUSIONS: Results confirm BE4 system can work in vivo with high precision and efficacy, and has great potentials in clinic to repair human genetic mutations.

Systems biology analysis of the radiation- attenuated schistosome vaccine reveals a role for growth factors in protection and hemostasis inhibition in parasite survival

In spite of several decades of research, an effective vaccine against schistosomiasis remains elusive. The radiation-attenuated (RA) cercarial vaccine is still the best model eliciting high protection levels, although the immune mechanisms have not yet been fully characterized. In order to identify genes and pathways underlying protection we investigated patterns of gene expression in PBMC and skin draining Lymph Nodes (LN) from mice using two exposure comparisons: vaccination with 500 attenuated cercariae versus infection with 500 normal cercariae; one versus three doses. Vaccinated mice were challenged with 120 normal parasites. Integration of PBMC and LN data from the infected group revealed early up-regulation of pathways associated with Th2 skewing and polarization of IgG antibody profiles. Additionally, hemostasis pathways were downregulated in infected mice, correlating with platelet reduction, potentially a mechanism to assist parasite migration through capillary beds. Conversely, up regulation of such mechanisms after vaccination may explain parasite blockade in the lungs. In contrast, a single exposure to attenuated parasites revealed early establishment of a Th1 bias (signaling of IL-1, IFN-γ; and Leishmania infection). Genes encoding chemokines and their receptors were more prominent in vaccinated mice, indicating an enhanced capacity for inflammation, potentially augmenting the inhibition of intravascular migration. Increasing the vaccinations from one to three did not dramatically elevate protection, but there was a clear shift towards antibody-mediated effectors. However, elements of the Th1 bias were still evident. Notable features after three vaccinations were markers of cytotoxicity (including IL-6 and NK cells) together with growth factors and their receptors (FGFR/VEGF/EGF) and the apoptosis pathway. Indeed, there is evidence for the development of anergy after three vaccinations, borne out by the limited responses detected in samples after challenge. We infer that persistence of a Th1 response puts a limit on expression of antibody-mediated mechanisms. This feature may explain the failure of multiple doses to drive protection towards sterile immunity. We suggest that the secretions of lung stage parasites would make a novel cohort of antigens for testing in protection experiments.

Differential proteomic analysis of children infected with respiratory syncytial virus

Respiratory syncytial virus (RSV) infection is the main cause of lower respiratory tract infection in children. However, there is no effective treatment for RSV infection. Here, we aimed to identify potential biomarkers to aid in the treatment of RSV infection. Children in the acute and convalescence phases of RSV infection were recruited and proteomic analysis was performed to identify differentially expressed proteins (DEPs). Subsequently, promising candidate proteins were determined by functional enrichment and protein-protein interaction network analysis, and underwent further validation by western blot both in clinical and mouse model samples. Among the 79 DEPs identified in RSV patient samples, 4 proteins (BPGM, TPI1, PRDX2, and CFL1) were confirmed to be significantly upregulated during RSV infection. Functional analysis showed that BPGM and TPI1 were mainly involved in glycolysis, indicating an association between RSV infection and the glycolysis metabolic pathway. Our findings provide insights into the proteomic profile during RSV infection and indicated that BPGM, TPI1, PRDX2, and CFL1 may be potential therapeutic biomarkers or targets for the treatment of RSV infection.

Decreased expression of microRNA-17 in hippocampal tissues and blood from mice with depression up-regulates the expression of PAI-1 mRNA and protein

This study determined the expression of plasminogen activator inhibitor-1 (PAI-1) and microRNA (miR)-17 in a mouse depression model. Forty male mice were divided evenly into control and depression groups. A chronic unpredictable mild stress (CUMS) model was constructed. qRT-PCR was used to determine the expression of PAI-1 mRNA and miR-17. Western blotting and ELISA were used to determine expression of PAI-1 protein. Dual luciferase reporter assay was carried out to identify direct interaction between miR-17 and PAI-1 mRNA. The mice with depression had elevated PAI-1 mRNA and protein in hippocampal tissues and blood. Expression of miR-17 was decreased in hippocampal tissues and blood from mice with depression. miR-17 bound with the 3′-UTR of PAI-1 mRNA to regulate its expression. This study demonstrated that miR-17 expression in hippocampal tissues and blood from mice with depression was decreased while expression of PAI-1 mRNA and protein was up-regulated. miR-17 participated in depression in mice by regulating PAI-1.

Chronic prostatitis alters the prostatic microenvironment and accelerates preneoplastic lesions in C57BL/6 mice

BACKGROUND: Chronic prostatitis has been supposed to be associated with preneoplastic lesions and cancer development. The objective of this study was to examine how chronic inflammation results in a prostatic microenvironment and gene mutation in C57BL/6 mice. METHODS: Immune and bacterial prostatitis mouse models were created through abdominal subcutaneous injection of rat prostate extract protein immunization (EAP group) or transurethral instillation of uropathogenic E. coli 1677 (E. coli group). Prostate histology, serum cytokine level, and genome-wide exome (GWE) sequences were examined 1, 3, and 6 months after immunization or injection. RESULT: In the EAP and E. coli groups, immune cell infiltrations were observed in the first and last months of the entire experiment. After 3 months, obvious proliferative inflammatory atrophy (PIA) and prostatic intraepithelial neoplasia (PIN) were observed accompanied with fibrosis hyperplasia in stroma. The decrease in basal cells (Cytokeratin (CK) 5+/p63+) and the accumulation of luminal epithelial cells (CK8+) in the PIA or PIN area indicated that the basal cells were damaged or transformed into different luminal cells. Hic1, Zfp148, and Mfge8 gene mutations were detected in chronic prostatitis somatic cells. CONCLUSION: Chronic prostatitis induced by prostate extract protein immunization or E. coli infection caused a reactive prostatic inflammation microenvironment and resulted in tissue damage, aberrant atrophy, hyperplasia, and somatic genome mutation.

Avances en las inmunoterapias para alergias alimentarias / New insights in immunotherapies for food allergies / Novas perspectivas em imunoterapias para alergias alimentares

Las enfermedades alérgicas son las inmunopatologías que con mayor prevalencia se presentan en el mundo. Pueden o no estar mediadas por anticuerpos IgE, sin embargo estas últimas son las que más intensamente se han estudiado por el riesgo que presentan para la vida del paciente. Si bien el único tratamiento que logra revertir estos mecanismos es la no exposición al alergeno, esto no siempre es posible. Por esta razón, y a partir del mayor conocimiento alcanzado del sistema inmune de mucosas junto al desarrollo de modelos animales de alergia, existe un marcado interés en la especialidad para el desarrollo de inmunoterapias que controlen y reviertan el estado de alergia. A partir de los ensayos pre-clínicos en animales y la aplicación de protocolos terapéuticos en ensayos clínicos, se han desarrollado terapias mucosales que logran inducir mecanismos de tolerancia específicos del alergeno, los cuales son capaces de revertir la sensibilización alérgica. Dado que el principal escollo siguen siendo las reacciones adversas inducidas durante el tratamiento, se requiere profundizar los estudios para desarrollar protocolos terapéuticos más seguros. En este punto la medicina traslacional encuentra un campo próspero para fortalecer las interacciones entre la ciencia básica, la aplicada y la clínica.

Allergic diseases are the most prevalent immunopathologies worldwide. Although different mechanisms -IgE-independent or IgE-dependent- can be involved in the immunopathogenesis, the latter are the most studied reactions since they can be life-threatening. Nowadays, allergen avoidance is the unique effective treatment for allergic patients. However, this is rather difficult to implement. For this reason, and based on the new insights into the mucosal immune system and the development of animal models of allergy, there is an increasing interest in developing novel therapies to control or reverse allergic disorders. Pre-clinical studies and clinical trials have been successful to prove that immunotherapies may accomplish mucosal mechanisms of allergen-specific tolerance, which are able to revoke the allergic sensitization. Since the main obstacle in these therapies still has adverse reactions induced during treatment, further studies are required to explore safe and effective therapeutic protocols. At this point, translational medicine is a flourishing field in the areas of basic science, applied science, and clinical research.

As doenças alérgicas são as imunopatologias mais prevalentes em todo o mundo. Embora possam estar mediadas ou não por anticorpos IgE, estas últimas são as reacções mais intensamente estudadas, devido ao risco que apresentam para a vida do paciente. Ainda que o único tratamento eficaz para reverter este mecanismos seja a não exposição dos pacientes ao alergeno, isto nem sempre é possível. Por este motivo, e com base nas novas perspectivas sobre o sistema imune de mucosas, junto com o desenvolvimento de modelos e para o animais de alergia, existe um interesse crescente na especialidade para o desenvolvimento de imunoterapias que controlem e revertam o estado de alergia. A partir de estudos pré-clínicos em animais e a aplicação de protocolos terapêuticos em ensaios clínico, foram desenvolvidas terapias mucosas que conseguem induzir mecanismos de tolerância específicos do alergeno, que são capazes de reverter a sensibilização alérgica. Devido a que o principal obstáculo nestas terapias continuam sendo as reações adversas induzidas durante o tratamento, é necessário realizar mais estudos para desenvolver protocolos terapêuticos mais seguros. Neste ponto, medicina translacional é um campo próspero para fortalecer as interações entre a ciência básica, a aplicada e a clínica.

Investigating the effect of the homeopathic immunomodulator, MODUL8® on Blood count, bronchial lavage and fibrin ultrastructure on experimental asthmatic BALB/c mice / Investigación del efecto del inmunomodulador homeopatico Modul8® sobre sangre, lavado bronquial y ultraestructura de la fibrina en ratones experimentales asmáticos BALB/c

Modul8® is a composite mixture of natural products that are known to be an immunomodulator. In the current study the effect of this immunomodulator is tested on an experimental asthmatic BALB/c mouse model to investigate its properties on the white blood cell count in the blood and bronchial lavage of the animals since white blood cells play a fundamental role in the inflammatory process involved in asthma. As it is known that platelets also play an important role in the immune system, the ultrastructure of platelets and fibrin networks were also investigated by scanning electron microscopy. The animals were sensitised, nebulized and treated over a period of 43 days until termination. Results from the blood smears as well as the bronchial lavage smears revealed significantly higher eosinophil counts in the asthmatic group compared to the control and treated groups. Changes in the ultrastructure of the platelets and fibrin networks could also be observed, with the Modul8® -treated group appearing similar to that of the control group where thick major and thin minor fibres could clearly be distinguished and a tight mass of platelet aggregate could be observed. Whereas the fibrin networks from the asthmatic animals appeared flimsy with a tight mass of thin fibres covering the thick major fibres. The asthmatic platelet aggregates appeared granular without the tight round appearance of the control platelet aggregates. It is therefore concluded that Modul8® positively influences the white blood cell counts by altering the asthmatic profile to look similar to that of the control. Also, it seems as if Modul8® has a stabilizing effect on the platelets and fibrin networks. From these results it can be suggested that Modul8® might successfully be used in the treatment of inflammatory conditions such as asthma.

Modul8® es una mezcla compuesta de productos naturales que es conocida por ser un inmunomodulador. En el presente estudio, el efecto de este inmunomodulador se prueba de forma experimental en el modelo de ratón asmáticos BALB/c, para investigar sus propiedades sobre el conteo de glóbulos blancos en la sangre y lavado bronquial de los animales, ya que los glóbulos blancos desempeñan un papel fundamental en el proceso de respuesta inflamatoria implicado en el asma. Como es sabido, también las plaquetas desempeñan un papel importante en el sistema inmunológico, así, la ultraestructura de las plaquetas y las redes de fibrina también fueron investigadas por microscopía electrónica de barrido. Los animales fueron sensibilizados, nebulizados y tratados durante un período de 43 días hasta el término. Los resultados de los frotis de sangre, así como los de lavado bronquial revelaron un número significativamente mayor de eosinófilos en el grupo de asmáticos en comparación con el control y grupos tratados. Cambios en la ultraestructura de las plaquetas y redes de fibrina también pueden ser observados, donde el grupo tratado con la Modul8® aparece similar a el grupo control, donde los fibras de mayor grosor y menor grosor pueden ser claramente distinguidas y además, puede ser observada una apretada masa de plaquetas aglutinadas. Considerando las redes de la fibrina en animales asmáticos parecen endebles con una apretada masa de fibras de menor grosor que cubren las fibras de mayor grosor. Los agregados de plaquetas en asmáticos aparecen granulares sin el aspecto apretado del agregado plaquetario que rodea al grupo control. Por tanto, se concluye que Modul8® positivamente influye en el conteo de glóbulos blancos mediante la alteración del perfil de asmáticos a un aspecto similar al del control. Además, parece como si Modul8® tuviera un efecto estabilizador en las plaquetas y las redes de fibrina. De estos resultados se puede sugerir que Modul8® puede ser utilizado...