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1.
Background
Airway epithelium is an active and important component of the immunological response in the pathophysiology of obstructive lung diseases. Recent studies suggest an important role for vitamin D3 in asthma severity and treatment response.Objective
Our study evaluated the influence of an active form of vitamin D3 on the expression of selected mediators of allergic inflammation in the respiratory epithelium.Material and Methods
Primary nasal and bronchial epithelial cells were exposed to1,25D3 for 1 hour and were then stimulated or not with IL-4, TNF-α, LPS, and poly I:C. After 24 hours TSLP, IL-33, and IL-25 protein levels were measured in culture supernatants usingELISAandmRNAlevels in cells by real time PCR.Results
1,25D3 increased TSLP concentration in unstimulated nasal epithelial cells, but did not influence IL-33 and IL-25 expression. In IL-4-stimulated epithelial cell cultures 1,25D3 mostly inhibited TSLP and IL-33 expression. In LPS-treated cultures 1,25D3 decreased IL-33 expression. Simultaneously 1,25D3 augmented IL-25 production in the same model of stimulation.Conclusion
Our study revealed the dual nature of vitamin D3 manifested in both pro- and anti-inflammatory properties observed in airway epithelial cells.2.
Background
Mitochondria exhibit a dynamic morphology in cells and their biogenesis and function are integrated with the nuclear cell cycle. In mitotic cells, the filamentous network structure of mitochondria takes on a fragmented form. To date, however, whether mitochondrial fusion activity is regulated in mitosis has yet to be elucidated.Findings
Here, we report that mitochondria were found to be fragmented in G2 phase prior to mitotic entry. Mitofusin 1 (Mfn1), a mitochondrial fusion protein, interacted with cyclin B1, and their interactions became stronger in G2/M phase. In addition, MARCH5, a mitochondrial E3 ubiquitin ligase, reduced Mfn1 levels and the MARCH5-mediated Mfn1 ubiquitylation were enhanced in G2/M phase.Conclusions
Mfn1 is degraded through the MARCH5-mediated ubiquitylation in G2/M phase and the cell cycle-dependent degradation of Mfn1 could be facilitated by interaction with cyclin B1/Cdk1 complexes.3.
4.
Carmine Mancone Alessio Grimaldi Giulia Refolo Isabella Abbate Gabriella Rozera Dario Benelli Gian Maria Fimia Vincenzo Barnaba Marco Tripodi Mauro Piacentini Fabiola Ciccosanti 《Proteome science》2017,15(1):18
Background
Changes in iron metabolism frequently accompany HIV-1 infection. However, while many clinical and in vitro studies report iron overload exacerbates the development of infection, many others have found no correlation. Therefore, the multi-faceted role of iron in HIV-1 infection remains enigmatic.Methods
RT-qPCR targeting the LTR region, gag, Tat and Rev were performed to measure the levels of viral RNAs in response to iron overload. Spike-in SILAC proteomics comparing i) iron-treated, ii) HIV-1-infected and iii) HIV-1-infected/iron treated T lymphocytes was performed to define modifications in the host cell proteome. Data from quantitative proteomics were integrated with the HIV-1 Human Interaction Database for assessing any viral cofactors modulated by iron overload in infected T lymphocytes.Results
Here, we demonstrate that the iron overload down-regulates HIV-1 gene expression by decreasing the levels of viral RNAs. In addition, we found that iron overload modulates the expression of many viral cofactors. Among them, the downregulation of the REV cofactor eIF5A may correlate with the iron-induced inhibition of HIV-1 gene expression. Therefore, we demonstrated that eiF5A downregulation by shRNA resulted in a significant decrease of Nef levels, thus hampering HIV-1 replication.Conclusions
Our study indicates that HIV-1 cofactors influenced by iron metabolism represent potential targets for antiretroviral therapy and suggests eIF5A as a selective target for drug development.5.
Peter M Huelsmann Andreas D Hofmann Stefanie A Knoepfel Jasmin Popp Pia Rauch Francesca Di Giallonardo Christina Danke Eva Gueckel Axel Schambach Horst Wolff Karin J Metzner Christian Berens 《BMC biotechnology》2011,11(1):4
Background
Regulated expression of suicide genes is a powerful tool to eliminate specific subsets of cells and will find widespread usage in both basic and applied science. A promising example is the specific elimination of human immunodeficiency virus type 1 (HIV-1) infected cells by LTR-driven suicide genes. The success of this approach, however, depends on a fast and effective suicide gene, which is expressed exclusively in HIV-1 infected cells. These preconditions have not yet been completely fulfilled and, thus, success of suicide approaches has been limited so far. We tested truncated Bid (tBid), a human pro-apoptotic protein that induces apoptosis very rapidly and efficiently, as suicide gene for gene therapy against HIV-1 infection.Results
When tBid was introduced into the HIV-1 LTR-based, Tat- and Rev-dependent transgene expression vector pLRed(INS)2R, very efficient induction of apoptosis was observed within 24 hours, but only in the presence of both HIV-1 regulatory proteins Tat and Rev. Induction of apoptosis was not observed in their absence. Cells containing this vector rapidly died when transfected with plasmids containing full-length viral genomic DNA, completely eliminating the chance for HIV-1 replication. Viral replication was also strongly reduced when cells were infected with HIV-1 particles.Conclusions
This suicide vector has the potential to establish a safe and effective gene therapy approach to exclusively eliminate HIV-1 infected cells before infectious virus particles are released.6.
Background
A majority of autoimmune diseases, including systemic lupus erythematosus (SLE), occur predominantly in females. Recent studies have identified specific dysregulated microRNAs (miRNAs) in both human and murine lupus, implying an important contribution of these miRNAs to lupus pathogenesis. However, to date, there is no study that examined sex differences in miRNA expression in immune cells as a plausible basis for sex differences in autoimmune disease. This study addresses this aspect in NZB/WF1 mice, a classical murine lupus model with marked female bias, and further investigates estrogen regulation of lupus-associated miRNAs.Methods
The Taqman miRNA assay system was used to quantify the miRNA expression in splenocytes from male and female NZB/WF1 mice at 17–18, 23, and 30 weeks (wks) of age. To evaluate potential estrogen's effect on lupus-associated miRNAs, 6-wk-old NZB/WF1 male mice were orchidectomized and surgically implanted with empty (placebo) or estrogen implants for 4 and 26 wks, respectively. To assess the lupus status in the NZB/WF1 mice, serum anti-dsDNA autoantibody levels, proteinuria, and renal histological changes were determined.Results
The sex differences in the expression of lupus-associated miRNAs, including the miR-182-96-183 cluster, miR-155, miR-31, miR-148a, miR-127, and miR-379, were markedly evident after the onset of lupus, especially at 30 wks of age when female NZB/WF1 mice manifested moderate to severe lupus when compared to their male counterparts. Our limited data also suggested that estrogen treatment increased the expression of aforementioned lupus-associated miRNAs, with the exception of miR-155, in orchidectomized male NZB/WF1 mice to a similar level in age-matched intact female NZB/WF1 mice. It is noteworthy that orchiectomy, itself, did not affect the expression of lupus-associated miRNAs.Conclusion
To our knowledge, this is the first study that demonstrated sex differences in the expression of lupus-associated miRNAs in splenocytes, especially in the context of autoimmunity. The increased expression of lupus-associated miRNA in female NZB/WF1 mice and conceivably in estrogen-treated orchidectomized male NZB/WF1 mice was associated with lupus manifestation. The notable increase of lupus-associated miRNAs in diseased, female NZB/WF1 mice may be a result of both lupus manifestation and the female gender.7.
Jonathan M. Wagner Sum Chan Timothy J. Evans Sara Kahng Jennifer Kim Mark A. Arbing David Eisenberg Konstantin V. Korotkov 《BMC structural biology》2016,16(1):5
Background
The ESX-1 type VII secretion system is an important determinant of virulence in pathogenic mycobacteria, including Mycobacterium tuberculosis. This complicated molecular machine secretes folded proteins through the mycobacterial cell envelope to subvert the host immune response. Despite its important role in disease very little is known about the molecular architecture of the ESX-1 secretion system.Results
This study characterizes the structures of the soluble domains of two conserved core ESX-1 components – EccB1 and EccD1. The periplasmic domain of EccB1 consists of 4 repeat domains and a central domain, which together form a quasi 2-fold symmetrical structure. The repeat domains of EccB1 are structurally similar to a known peptidoglycan binding protein suggesting a role in anchoring the ESX-1 system within the periplasmic space. The cytoplasmic domain of EccD1has a ubiquitin-like fold and forms a dimer with a negatively charged groove.Conclusions
These structures represent a major step towards resolving the molecular architecture of the entire ESX-1 assembly and may contribute to ESX-1 targeted tuberculosis intervention strategies.8.
Asrin Rahimi Iraj Amiri Amaneh Mohammadi Roushandeh Zoleikha Golipour Choshali Zohreh Alizadeh Tayebeh Artimani Saeid Afshar Sara Soleimani Asl 《Biotechnology letters》2018,40(3):609-615
Objective
To investigate the effect of H2O2 on the migration and antioxidant defense of mesenchymal stem cells (MSCs) and the neurotrophic effects of H2O2-treated MSCs on spinal cord injury (SCI).Results
Sublethal concentrations of H2O2 decreased cell migration and expression of CXCR4 and CCR2 as well as Nrf2 expression in MSCs. In the second phase, transplantation of treated and untreated MSCs to SCI caused minor changes in locomotor dysfunction. There was a significantly difference between cell-treated and spinal cord injury groups in expression of BDNF (brain-derived neurotrophic factor). Transplantation of H2O2-treated cells caused an increase in BDNF expression compared to non-treated cells.Conclusion
Transplantation of H2O2-treated stem cells may have protective effects against SCI through by increasing neurotrophic factors.9.
10.
Simone Vassiliadis Kim M. Plummer Kevin S. Powell Simone J. Rochfort 《Metabolomics : Official journal of the Metabolomic Society》2018,14(10):133
Introduction
The aphid Rhopalosiphum padi L. is a vector of Barley yellow dwarf virus (BYDV) in wheat and other economically important cereal crops. Increased atmospheric CO2 has been shown to alter plant growth and metabolism, enhancing BYDV disease in wheat. However, the biochemical influences on aphid metabolism are not known.Objectives
This work aims to determine whether altered host-plant quality, influenced by virus infection and elevated CO2, impacts aphid weight and metabolism.Methods
Untargeted 1H NMR metabolomics coupled with multivariate statistics were employed to profile the metabolism of R. padi reared on virus-infected and non-infected (sham-inoculated) wheat grown under ambient CO2 (aCO2, 400 µmol mol?1) and future, predicted elevated CO2 (eCO2, 650 µmol mol?1) concentrations. Un-colonised wheat was also profiled to observe changes to host-plant quality (i.e., amino acids and sugars).Results
The direct impacts of virus or eCO2 were compared. Virus presence increased aphid weight under aCO2 but decreased weight under eCO2; whilst eCO2 increased non-viruliferous (sham) aphid weight but decreased viruliferous aphid weight. Discriminatory metabolites due to eCO2 were succinate and sucrose (in sham wheat), glucose, choline and betaine (in infected wheat), and threonine, lactate, alanine, GABA, glutamine, glutamate and asparagine (in aphids), irrespective of virus presence. Discriminatory metabolites due to virus presence were alanine, GABA, succinate and betaine (in wheat) and threonine and lactate (in aphids), irrespective of CO2 treatment.Conclusion
This study confirms that virus and eCO2 alter host-plant quality, and these differences are reflected by aphid weight and metabolism.11.
Background
Despite the durable viral suppression afforded by antiretroviral therapy, HIV-1 eradication will require strategies to target latently infected cells that persist in infected individuals. Protein kinase C (PKC) activation is a promising strategy to reactivate latent proviruses and allow for subsequent recognition and clearance of infected cells by the immune system. Ingenol derivatives are PKC agonists that induce latency reversal but also lead to T cell activation and the release of pro-inflammatory cytokines, which would be undesirable in vivo. In this work, we sought to identify compounds that would suppress pro-inflammatory cytokine production in the context of PKC activation.Design and methods
We performed an in vitro screen to identify compounds that could dampen pro-inflammatory cytokine release associated with T cell activation, using IL-6 as a model cytokine. We then tested the ability of the most promising screening hit, the FDA-approved Janus Kinase (JAK) inhibitor ruxolitinib, to diminish release of multiple cytokines and its effect on latency reversal using cells from HIV-1-positive, aviremic participants.Results
We demonstrate that co-administration of ruxolitinib with ingenol-3,20-dibenzoate significantly reduces pro-inflammatory cytokine release without impairing latency reversal ex vivo.Conclusion
The combination of ingenol compounds and JAK inhibition represents a novel strategy for HIV-1 eradication.12.
Background
One of the major functions of Nef is in the enhancement of the infectivity of the human and simian immunodeficiency viruses (HIV and SIV, respectively). However, the detailed mechanism of the enhancement of viral infectivity by Nef remains unclear. Additionally, studies of mechanisms by which Nef enhances the infectivity of SIV are not as intensive as those of HIV-1.Methods
We generated short-lived Nef constructed by fusing Nef to a proteasome-mediated protein degradation sequence to characterize the Nef role in viral infectivity.Results
The apparent expression level of the short-lived Nef was found to be extremely lower than that of the wild-type Nef. Moreover, the expression level of the short-lived Nef increased with the treatment with a proteasome inhibitor. The infectivity of HIV-1 with the short-lived Nef was significantly lower than that with the wild-type Nef. On the other hand, the short-lived Nef enhanced the infectivity of SIVmac239, an ability observed to be interestingly equivalent to that of the wild-type Nef. The short-lived Nef was not detected in SIVmac239, but the wild-type Nef was, suggesting that the incorporation of Nef into SIVmac239 is not important for the enhancement of SIVmac239 infectivity.Conclusions
Altogether, the findings suggest that the mechanisms of infectivity enhancement by Nef are different between HIV-1 and SIVmac239. Lastly, we propose the following hypothesis: even when the expression level of a protein is extremely low, the protein may still be sufficiently functional.13.
Xiaoying Zhang Wei Chen Ruth Guillermo Gudiseva Chandrasekher Radhey S Kaushik Alan Young Hesham Fahmy Chandradhar Dwivedi 《BMC research notes》2010,3(1):220
Background
α-Santalol, an active component of sandalwood oil, has shown chemopreventive effects on skin cancer in different murine models. However, effects of α-santalol on cell cycle have not been studied. Thus, the objective of this study was to investigate effects of α-santalol on cell cycle progression in both p53 mutated human epidermoid carcinoma A431 cells and p53 wild-type human melanoma UACC-62 cells to elucidate the mechanism(s) of action.Methods
MTT assay was used to determine cell viability in A431 cells and UACC-62; fluorescence-activated cell sorting (FACS) analysis of propidium iodide staining was used for determining cell cycle distribution in A431 cells and UACC-62 cells; immunoblotting was used for determining the expression of various proteins and protein complexes involved in the cell cycle progression; siRNA were used to knockdown of p21 or p53 in A431 and UACC-62 cells and immunofluorescence microscopy was used to investigate microtubules in UACC-62 cells.Results
α-Santalol at 50-100 μM decreased cell viability from 24 h treatment and α-santalol at 50 μM-75 μM induced G2/M phase cell cycle arrest from 6 h treatment in both A431 and UACC-62 cells. α-Santalol altered expressions of cell cycle proteins such as cyclin A, cyclin B1, Cdc2, Cdc25c, p-Cdc25c and Cdk2. All of these proteins are critical for G2/M transition. α-Santalol treatment up-regulated the expression of p21 and suppressed expressions of mutated p53 in A431 cells; whereas, α-santalol treatment increased expressions of wild-type p53 in UACC-62 cells. Knockdown of p21 in A431 cells, knockdown of p21 and p53 in UACC-62 cells did not affect cell cycle arrest caused by α-santalol. Furthermore, α-santalol caused depolymerization of microtubules similar to vinblastine in UACC-62 cells.Conclusions
This study for the first time identifies effects of α-santalol in G2/M phase arrest and describes detailed mechanisms of G2/M phase arrest by this agent, which might be contributing to its overall cancer preventive efficacy in various mouse skin cancer models.14.
Background
Latent reservoirs of HIV-1 provide a major challenge to its cure. There are increasing reports of interplay between HIV-1 replication and host miRNAs. Several host miRNAs, which potentially target the nef-3′LTR region of HIV-1 RNA, including miR-29a, are proposed to promote latency.Findings
We used two established cellular models of HIV-1 latency – the U1 monocytic and J1.1 CD4+ T cell lines to show an inverse relationship between HIV-1 replication and miR-29a levels, which was mediated by the HIV-1 Nef protein. Using a miR-29a responsive luciferase reporter plasmid, an expression plasmid and an anti-miR29a LNA, we further demonstrate increased miR-29a levels during latency and reduced levels following active HIV replication. Finally, we show that miR-29a levels in the PBMCs and plasma of HIV infected persons also correlate inversely with latency and active viral replication.Conclusions
The levels of miR-29a correlate inversely with active HIV-1 replication in cell culture models and in HIV infected persons. This links miR-29a to viral latency and suggests another approach to activate and destroy latent HIV-1 reservoirs.15.
Zeinab Panahi Asghar Abdoli Ghasem Mosayebi Mehdi Mahdavi Fariborz Bahrami 《Biotechnology letters》2018,40(3):527-533
Objective
To evaluate the combined effects of CpG oligodeoxynucleotides (CpG-ODNs) adjuvant and subcutaneous injection route on efficacy of a HIV-1-tat DNA vaccine candidate using BALB/c mice as an animal model.Results
Evaluation of cellular and humoral immunity of mice injected subcutaneously with HIV-1-tat gene cloned into a pcDNA3.1 vector indicated that significant levels of IFN-γ cytokine secretion (900 pg/ml), lymphocyte proliferation (2.5 stimulation index) and IgG2a (1.45 absorbance 450 nm) production could be achieved. These indicators of stimulated cellular immunity were elicited 2 weeks after the last injection (P < 0.05).Conclusions
Formulation of HIV-1-tat DNA vaccine candidate with CpG-ODNs as an adjuvant while administrated subcutaneously are a promising approach to induce effective cellular immunity responses against HIV-1 infection.16.
Background
Stress urinary incontinence (SUI) is a relatively common disorder that significantly affects the quality of life. Many conservative and surgical treatment methods have been recommended for SUI, but they have major limitations.Aims
To assess the use of the CO2 fractional laser in the treatment of SUI.Methods
This clinical trial included 55 patients with confirmed SUI. Patients underwent fractional CO2 laser treatment 3 times at 30-day intervals. Data on age, smoking history, sexual activity, menopause, and history of hormone replacement therapy (HRT) were collected. Response to treatment was assessed by SUI severity and the level of sexual satisfaction was assessed using the visual analog scale (VAS). Patients were evaluated at 3 different time points: before treatment, and 45 days and 6 months after the last laser treatment.Results
The mean patient age was 44.4±11.4 years (range: 28 to 68 years). Smoking history was positive in 6 patients (9.1%); 19 (54.3%) were menopausal on HRT. The SUI severity score at baseline (before treatment) was 8.56±0.62 and decreased to 2.28 6 months after treatment (p<0.0001). The sexual satisfaction score was 3±0.94 at baseline and increased to 7.87±0.93 6 months after treatment (day 180) (p<0.0001, slope = + 2.2)Conclusion
Our findings are in line with a previous study that showed the value of transvaginal CO2 fractional laser treatment for alleviation of SUI symptoms and its potential as an alternative treatment. We also observed improved sexual satisfaction in SUI patients.17.
Background
The recently discovered small-molecule BI-2 potently blocks HIV-1 infection. BI-2 binds to the N-terminal domain of HIV-1 capsid. BI-2 utilizes the same capsid pocket used by the small molecule PF74. Although both drugs bind to the same pocket, it has been proposed that BI-2 uses a different mechanism to block HIV-1 infection when compared to PF74.Findings
This work demonstrates that BI-2 destabilizes the HIV-1 core during infection, and prevents the binding of the cellular factor CPSF6 to the HIV-1 core.Conclusions
Overall this short-form paper suggests that BI-2 is using a similar mechanism to the one used by PF74 to block HIV-1 infection.18.
E. Vamvaka A. Evans K. Ramessar L. R. H. Krumpe R. J. Shattock B. R. O’Keefe P. Christou T. Capell 《Plant cell reports》2016,35(6):1309-1319
Key message
Cyanovirin-N produced in rice endosperm provides efficient pre-exposure prophylaxis against HIV-1 BaL infection in vitro.Abstract
Cyanovirin-N (CV-N) is a lectin with potent antiviral activity that has been proposed as a component of microbicides for the prevention of infection with Human immunodeficiency virus (HIV). The production of protein-based microbicide components requires a platform that is sufficiently economical and scalable to meet the demands of the large at-risk population, particularly in resource poor developing countries. We, therefore, expressed CV-N in rice endosperm, because the dried seed is ideal for storage and transport and crude extracts could be prepared locally and used as a microbicide component without further purification. We found that crude extracts from rice seeds expressing up to 10 µg CV-N per gram dry seed weight showed dose-dependent gp120 binding activity, confirming that the protein was soluble, correctly folded and active. The recombinant lectin (OSCV-N) reduced the infectivity of HIV-1BaL (an R5 virus strain representing the majority of transmitted infections) by ~90 % but showed only weak neutralization activity against HIV-1RF (representative of X4 virus, rarely associated with transmission), suggesting it would be highly effective for pre-exposure prophylaxis against the vast majority of transmitted strains. Crude extracts expressing OSCV-N showed no toxicity towards human cells at working dilutions indicating that microbicide components produced in rice endosperm are safe for direct application as topical microbicides in humans.19.
Background
In HIV-1 infected patients, production of interleukin-10 (IL-10), a highly immunosuppressive cytokine, is associated with progression of infection toward AIDS. HIV-1 Tat protein, by interacting with TLR4-MD2 at the membrane level, induces IL-10 production by primary human monocytes and macrophages. In the present study we evaluated the effect of the TLR4 antagonist Eritoran tetrasodium (E5564) on HIV-1 Tat-induced IL-10 production.Findings
Here, we confirm that the recombinant HIV-1 Tat protein and the GST-Tat 1–45 fusion protein efficiently stimulate IL-10 production by primary monocytes and macrophages and that this stimulation is inhibited by blocking anti-TLR4 mAbs. We show that a similar inhibition is observed by preincubating the cells with the TLR4 antagonist E5564.Conclusion
This study provides compelling data showing for the first time that the TLR4 antagonist E5564 inhibits the immunosuppressive cytokine IL-10 production by primary human monocytes and macrophages incubated in the presence of HIV-1 Tat protein.20.