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1.
bioRxiv ; 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39026883

ABSTRACT

Mounting evidence supports a critical role for central nervous system (CNS) glial cells in neuroinflammation and neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's Disease (PD), Multiple Sclerosis (MS), as well as neurovascular ischemic stroke. Previously, we found that loss of the PD-associated gene leucine-rich repeat kinase 2 ( Lrrk2 ) in macrophages, peripheral innate immune cells, induced mitochondrial stress and elevated basal expression of type I interferon (IFN) stimulated genes (ISGs) due to chronic mitochondrial DNA engagement with the cGAS/STING DNA sensing pathway. Here, we report that loss of LRRK2 results in a paradoxical response in microglial cells, a CNS-specific macrophage population. In primary murine microglia and microglial cell lines, loss of Lrrk2 reduces tonic IFN signaling leading to a reduction in ISG expression. Consistent with reduced type I IFN, mitochondria from Lrrk2 KO microglia are protected from stress and have elevated metabolism. These protective phenotypes involve upregulation of NRF2, an important transcription factor in the response to oxidative stress and are restricted by LRRK2 kinase activity. Collectively, these findings illustrate a dichotomous role for LRRK2 within different immune cell populations and give insight into the fundamental differences between immune regulation in the CNS and the periphery.

2.
Proc Natl Acad Sci U S A ; 121(9): e2312587121, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38381785

ABSTRACT

To ensure a robust immune response to pathogens without risking immunopathology, the kinetics and amplitude of inflammatory gene expression in macrophages need to be exquisitely well controlled. There is a growing appreciation for stress-responsive membraneless organelles (MLOs) regulating various steps of eukaryotic gene expression in response to extrinsic cues. Here, we implicate the nuclear paraspeckle, a highly ordered biomolecular condensate that nucleates on the Neat1 lncRNA, in tuning innate immune gene expression in murine macrophages. In response to a variety of innate agonists, macrophage paraspeckles rapidly aggregate (0.5 h poststimulation) and disaggregate (2 h poststimulation). Paraspeckle maintenance and aggregation require active transcription and MAPK signaling, whereas paraspeckle disaggregation requires degradation of Neat1 via the nuclear RNA exosome. In response to lipopolysaccharide treatment, Neat1 KO macrophages fail to properly express a large cohort of proinflammatory cytokines, chemokines, and antimicrobial mediators. Consequently, Neat1 KO macrophages cannot control replication of Salmonella enterica serovar Typhimurium or vesicular stomatitis virus. These findings highlight a prominent role for MLOs in orchestrating the macrophage response to pathogens and support a model whereby dynamic assembly and disassembly of paraspeckles reorganizes the nuclear landscape to enable inflammatory gene expression following innate stimuli.


Subject(s)
Paraspeckles , RNA, Long Noncoding , Humans , Animals , Mice , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Macrophages/metabolism
3.
Am J Kidney Dis ; 82(5): 543-558, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37356648

ABSTRACT

RATIONALE & OBJECTIVE: Vitamin D is widely used to manage chronic kidney disease-mineral and bone disorder (CKD-MBD). We evaluated the effects of vitamin D therapy on mortality, cardiovascular, bone, and kidney outcomes in adults with CKD. STUDY DESIGN: Systematic review of randomized controlled trials (RCT) with highly sensitive searching of MEDLINE, Embase, and CENTRAL, through February 25, 2023. SETTING & STUDY POPULATIONS: Adults with stage 3, 4, or 5 CKD, including kidney failure treated with dialysis. Recipients of a kidney transplant were excluded. SELECTION CRITERIA FOR STUDIES: RCTs with≥3 months of follow-up evaluating a vitamin D compound. DATA EXTRACTION: Data were extracted independently by three investigators. ANALYTICAL APPROACH: Treatment estimates were summarized using random effects meta-analysis. Primary review endpoints were all-cause death, cardiovascular death, and fracture. Secondary outcomes were major adverse cardiovascular events, hospitalization, bone mineral density, parathyroidectomy, progression to kidney failure, proteinuria, estimated glomerular filtration rate, hypercalcemia, hyperphosphatemia, biochemical markers of CKD-MBD, and various intermediate outcome measures of cardiovascular disease. Risk of bias was assessed using the Cochrane Risk of Bias (RoB) 2 tool. Evidence certainty was adjudicated using GRADE. RESULTS: Overall, 128 studies involving 11,270 participants were included. Compared with placebo, vitamin D therapy probably had no effect on all-cause death (relative risk [RR], 1.04; 95% CI, 0.84-1.24); and uncertain effects on fracture (RR, 0.68; 95% CI, 0.37-1.23) and cardiovascular death (RR, 0.73; 95% CI, 0.31-1.71). Compared with placebo, vitamin D therapy lowered serum parathyroid hormone and alkaline phosphatase, but increased serum calcium. LIMITATIONS: Data were limited by trials with short-term follow-up periods, small sample size, and the suboptimal quality. CONCLUSIONS: Vitamin D therapy did not reduce the risk of all-cause death in people with CKD. Effects on fracture and cardiovascular and kidney outcomes were uncertain. TRIAL REGISTRATION: Registered at PROSPERO with study number CRD42017057691. PLAIN-LANGUAGE SUMMARY: Chronic kidney disease (CKD) is associated with increased risk of death, cardiovascular disease, and fractures. This excess risk is thought to be related to changes in bone and mineral metabolism, leading to the development of CKD-mineral and bone disorder (CKD-MBD) which is characterized by vascular calcification and reduced bone quality. Vitamin D is commonly used in the treatment of this condition. We reviewed randomized controlled trials examining the effect of vitamin D therapy in CKD. We found that vitamin D therapy affects serum biomarkers, including an increase in serum calcium. However, it probably has no effect on risk of all-cause death in CKD, and the effects on other clinical bone, cardiovascular, and kidney outcomes are uncertain.

4.
Trends Cell Biol ; 33(9): 773-787, 2023 09.
Article in English | MEDLINE | ID: mdl-37062616

ABSTRACT

Since their discovery, members of the gasdermin (GSDM) family of proteins have been firmly established as executors of pyroptosis, with the N-terminal fragment of most GSDMs capable of forming pores in the plasma membrane. More recent findings suggest that some GSDMs can drive additional cell death pathways, such as apoptosis and necroptosis, through mechanisms independent of plasma membrane perforation. There is also emerging evidence that by associating with cellular compartments such as mitochondria, peroxisomes, endosomes, and the nucleus, GSDMs regulate cell death-independent aspects of cellular homeostasis. Here, we review the diversity of GSDM function across several cell types and explore how various cellular stresses can promote relocalization - and thus refunctionalization - of GSDMs.


Subject(s)
Gasdermins , Neoplasm Proteins , Humans , Neoplasm Proteins/metabolism , Apoptosis , Pyroptosis/physiology , Homeostasis , Inflammasomes/metabolism
5.
Eye (Lond) ; 37(8): 1652-1658, 2023 06.
Article in English | MEDLINE | ID: mdl-36028762

ABSTRACT

AIMS: To determine baseline visual acuity before the start of treatment for neovascular age-related macular degeneration (AMD), compare median and visual acuity states between treatment sites and investigate the association of socio-demographic and clinical characteristics with baseline acuity. METHODS: Anonymised demographic and clinical data, collected as part of routine clinical care, were extracted from electronic medical records at treating National Health Service (NHS) Trusts. Analyses were restricted to eyes with baseline visual acuity recorded at treatment initiation. Associations with baseline acuity were investigated using multivariate linear regression. RESULTS: Analysis included 12,414 eyes of 9116 patients at 13 NHS Trusts. Median baseline acuity was LogMAR 0.46 (interquartile range = 0.26-0.80) and 34.5% of eyes had good acuity, defined as LogMAR ≤0.3. Baseline acuity was positively associated with second-treated eye status, younger age, lower socio-economic deprivation, independent living, and female sex. There was little evidence of association between baseline acuity and distance to the nearest treatment centre, systemic or ocular co-morbidity. Despite case-mix adjustments, there was evidence of significant variation of baseline visual acuity between sites. CONCLUSIONS: Despite access to publicly funded treatment within the NHS, variation in visual acuity at the start of neovascular AMD treatment persists. Identifying the characteristics associated with poor baseline acuity, targeted health awareness campaigns, professional education, and pathway re-design may help to improve baseline acuity, the first eye gap, and visual acuity outcomes.


Subject(s)
Angiogenesis Inhibitors , Wet Macular Degeneration , Humans , Female , Angiogenesis Inhibitors/therapeutic use , Vascular Endothelial Growth Factor A , State Medicine , Visual Acuity , Wet Macular Degeneration/drug therapy
6.
Elife ; 112022 11 21.
Article in English | MEDLINE | ID: mdl-36409059

ABSTRACT

To mount a protective response to infection while preventing hyperinflammation, gene expression in innate immune cells must be tightly regulated. Despite the importance of pre-mRNA splicing in shaping the proteome, its role in balancing immune outcomes remains understudied. Transcriptomic analysis of murine macrophage cell lines identified Serine/Arginine Rich Splicing factor 6 (SRSF6) as a gatekeeper of mitochondrial homeostasis. SRSF6-dependent orchestration of mitochondrial health is directed in large part by alternative splicing of the pro-apoptosis pore-forming protein BAX. Loss of SRSF6 promotes accumulation of BAX-κ, a variant that sensitizes macrophages to undergo cell death and triggers upregulation of interferon stimulated genes through cGAS sensing of cytosolic mitochondrial DNA. Upon pathogen sensing, macrophages regulate SRSF6 expression to control the liberation of immunogenic mtDNA and adjust the threshold for entry into programmed cell death. This work defines BAX alternative splicing by SRSF6 as a critical node not only in mitochondrial homeostasis but also in the macrophage's response to pathogens.


Subject(s)
Alternative Splicing , Immunity, Innate , Mitochondria , bcl-2-Associated X Protein , Animals , Mice , bcl-2-Associated X Protein/genetics , DNA, Mitochondrial , Serine-Arginine Splicing Factors/metabolism
7.
BMJ Open Ophthalmol ; 7(1)2022 06.
Article in English | MEDLINE | ID: mdl-36161843

ABSTRACT

OBJECTIVE: To record visual acuity outcomes after 12 months of treatment for neovascular age-related macular degeneration (NvAMD), investigate variation between sites and explore associations with baseline characteristics and care processes. METHODS AND ANALYSIS: Anonymised demographic and clinical data were extracted from electronic medical records at treating National Health Service (NHS) Trusts. Associations with acuity outcomes were investigated using multivariate linear and logistic regression. RESULTS: Analysis included 9401 eyes (7686 patients) treated at 13 NHS Trusts. From baseline to month 12, median acuity improved from LogMAR 0.50 (IQR 0.30-0.80) to 0.40 (0.22-0.74) and the proportion of eyes with LogMAR ≥0.3 increased from 34.5% to 39.8%. Baseline visual acuity was the strongest predictor of visual acuity outcomes. For each LogMAR 0.1 worsening of baseline acuity, the acuity at 12 months was improved by LogMAR 0.074 (95% CI 0.073 to 0.074) and the odds of a 'poor' acuity outcome was multiplied by 1.66 (95% CI 1.61 to 1.70). Younger age, independent living status, lower socioeconomic deprivation, timely loading phase completion and higher number of injections were associated with better acuity outcomes. Despite case-mix adjustments, there was evidence of significant variation in acuity outcomes between sites. CONCLUSIONS: Even after adjustment for other variables, variation in acuity outcomes after NvAMD treatment within the NHS remains. Meaningful comparison of outcomes between different providers requires adjustment for a range of baseline characteristics, not visual acuity alone. Identifying best practice at sites with better outcomes and adapting local care processes are required to tackle this health inequality.


Subject(s)
Angiogenesis Inhibitors , Wet Macular Degeneration , Angiogenesis Inhibitors/therapeutic use , Health Status Disparities , Humans , State Medicine , Vascular Endothelial Growth Factor A , Visual Acuity , Wet Macular Degeneration/drug therapy
8.
Cell ; 185(17): 3214-3231.e23, 2022 08 18.
Article in English | MEDLINE | ID: mdl-35907404

ABSTRACT

Although mutations in mitochondrial-associated genes are linked to inflammation and susceptibility to infection, their mechanistic contributions to immune outcomes remain ill-defined. We discovered that the disease-associated gain-of-function allele Lrrk2G2019S (leucine-rich repeat kinase 2) perturbs mitochondrial homeostasis and reprograms cell death pathways in macrophages. When the inflammasome is activated in Lrrk2G2019S macrophages, elevated mitochondrial ROS (mtROS) directs association of the pore-forming protein gasdermin D (GSDMD) to mitochondrial membranes. Mitochondrial GSDMD pore formation then releases mtROS, promoting a switch to RIPK1/RIPK3/MLKL-dependent necroptosis. Consistent with enhanced necroptosis, infection of Lrrk2G2019S mice with Mycobacterium tuberculosis elicits hyperinflammation and severe immunopathology. Our findings suggest a pivotal role for GSDMD as an executer of multiple cell death pathways and demonstrate that mitochondrial dysfunction can direct immune outcomes via cell death modality switching. This work provides insights into how LRRK2 mutations manifest or exacerbate human diseases and identifies GSDMD-dependent necroptosis as a potential target to limit Lrrk2G2019S-mediated immunopathology.


Subject(s)
Mitochondria , Necroptosis , Phosphate-Binding Proteins/metabolism , Pore Forming Cytotoxic Proteins/metabolism , Animals , Humans , Inflammasomes , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 , Macrophages , Mice , Mitochondria/metabolism , Reactive Oxygen Species/metabolism
9.
Elife ; 92020 02 14.
Article in English | MEDLINE | ID: mdl-32057291

ABSTRACT

The Parkinson's disease (PD)-associated gene leucine-rich repeat kinase 2 (LRRK2) has been studied extensively in the brain. However, several studies have established that mutations in LRRK2 confer susceptibility to mycobacterial infection, suggesting LRRK2 also controls immunity. We demonstrate that loss of LRRK2 in macrophages induces elevated basal levels of type I interferon (IFN) and interferon stimulated genes (ISGs) and causes blunted interferon responses to mycobacterial pathogens and cytosolic nucleic acid agonists. Altered innate immune gene expression in Lrrk2 knockout (KO) macrophages is driven by a combination of mitochondrial stresses, including oxidative stress from low levels of purine metabolites and DRP1-dependent mitochondrial fragmentation. Together, these defects promote mtDNA leakage into the cytosol and chronic cGAS engagement. While Lrrk2 KO mice can control Mycobacterium tuberculosis (Mtb) replication, they have exacerbated inflammation and lower ISG expression in the lungs. These results demonstrate previously unappreciated consequences of LRRK2-dependent mitochondrial defects in controlling innate immune outcomes.


Parkinson's disease is a progressive nervous system disorder that causes tremors, slow movements, and stiff and inflexible muscles. The symptoms are caused by the loss of cells known as neurons in a specific part of the brain that helps to regulate how the body moves. Researchers have identified mutations in several genes that are associated with an increased risk of developing Parkinson's. The most common of these mutations occur in a gene called LRRK2. This gene produces a protein that has been shown to be important for maintaining cellular compartments known as mitochondria, which play a crucial role in generating energy. It remains unclear how these mutations lead to the death of neurons. Mutations in LRRK2 have also been shown to make individuals more susceptible to bacterial infections, suggesting that the protein that LRRK2 codes for may help our immune system. Weindel, Bell et al. set out to understand how this protein works in immune cells called macrophages, which 'eat' invading bacteria and produce type I interferons, molecules that promote immune responses. Mouse cells were used to measure the ability of normal macrophages and macrophages that lack the mouse equivalent to LRRK2 (referred to as Lrrk2 knockout macrophages) to make type I interferons. The experiments showed that the Lrrk2 knockout macrophages made type I interferons even when they were not infected with bacteria, suggesting they are subject to stress that triggers immune responses. It was possible to correct the behavior of the Lrrk2 knockout macrophages by repairing their mitochondria. When mice missing the gene equivalent to LRRK2 were infected with the bacterium that causes tuberculosis, they experienced more severe disease. The protein encoded by the LRRK2 gene is considered a potential target for therapies to treat Parkinson's disease, and several drugs that inhibit this protein are being tested in clinical trials. The findings of Weindel, Bell et al. suggest that these drugs may have unintended negative effects on a patient's ability to fight infection. This work also indicates that LRRK2 mutations may disrupt immune responses in the brain, where macrophage-like cells called microglia play a crucial role in maintaining healthy neurons. Future studies that examine how mutations in LRRK2 affect microglia may help us understand how Parkinson's disease develops.


Subject(s)
Homeostasis , Immunity, Innate , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Mitochondria/metabolism , Mycobacterium tuberculosis/metabolism , Animals , Humans , Interferon Type I/genetics , Interferon Type I/metabolism , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Mice , Mice, Knockout , Mutation , Mycobacterium tuberculosis/immunology , Parkinson Disease/metabolism , Sequence Analysis, RNA
10.
Article in English | MEDLINE | ID: mdl-31192157

ABSTRACT

Despite major strides in personalized genomics, it remains poorly understood why neurodegenerative diseases occur in only a fraction of individuals with a genetic predisposition and conversely, why individuals with no genetic risk of a disorder develop one. Chronic diseases like Alzheimer's, Parkinson's, and Multiple sclerosis are speculated to result from a combination of genetic and environmental factors, a concept commonly referred to as the "multiple hit hypothesis." A number of bacterial infections have been linked to increased risk of neurodegeneration, and in some cases, clearance of bacterial pathogens has been correlated with amelioration of central nervous system (CNS) deficits. Additionally, mutations in several genes known to contribute to CNS disorders like Parkinson's Disease have repeatedly been implicated in susceptibility to intracellular bacterial infection. Recent data has begun to demonstrate roles for these genes (PARK2, PINK1, and LRRK2) in modulating innate immune outcomes, suggesting that immune dysregulation may play an even more important role in neurodegeneration than previously appreciated. This review will broadly explore the connections between bacterial infection, immune dysregulation, and CNS disorders. Understanding this interplay and how bacterial pathogenesis contributes to the "multiple-hit hypothesis" of neurodegeneration will be crucial to develop therapeutics to effectively treat both neurodegeneration and infection.


Subject(s)
Bacterial Infections/complications , Bacterial Infections/immunology , Immunity, Innate , Neurodegenerative Diseases/physiopathology , Multiple Sclerosis/physiopathology , Parkinson Disease/physiopathology
12.
Cell Death Differ ; 26(2): 332-347, 2019 01.
Article in English | MEDLINE | ID: mdl-29786074

ABSTRACT

Interferons (IFNs) are critical determinants in immune-competence and autoimmunity, and are endogenously regulated by a low-level constitutive feedback loop. However, little is known about the functions and origins of constitutive IFN. Recently, lipopolysaccharide (LPS)-induced IFN was implicated as a driver of necroptosis, a necrotic form of cell death downstream of receptor-interacting protein (RIP) kinase activation and executed by mixed lineage kinase like-domain (MLKL) protein. We found that the pre-established IFN status of the cell, instead of LPS-induced IFN, is critical for the early initiation of necroptosis in macrophages. This pre-established IFN signature stems from cytosolic DNA sensing via cGAS/STING, and maintains the expression of MLKL and one or more unknown effectors above a critical threshold to allow for MLKL oligomerization and cell death. Finally, we found that elevated IFN-signaling in systemic lupus erythematosus (SLE) augments necroptosis, providing a link between pathological IFN and tissue damage during autoimmunity.


Subject(s)
Interferon-beta/metabolism , Macrophages/metabolism , Necroptosis , Protein Kinases/metabolism , Animals , Cell Survival/drug effects , Cells, Cultured , Cytosol/metabolism , DNA/metabolism , Gene Knockout Techniques , Humans , Interferon-beta/genetics , Interferon-beta/pharmacology , Lipopolysaccharides/pharmacology , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Nucleotidyltransferases/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics
13.
J Thromb Haemost ; 15(10): 1913-1922, 2017 10.
Article in English | MEDLINE | ID: mdl-28762617

ABSTRACT

Essentials Anticoagulants prevent venous thromboembolism but may be associated with greater bleeding risks. Bivariate analysis assumes a non-linear relationship between efficacy and safety outcomes. Extended full-dose betrixaban is favorable over standard enoxaparin in bivariate endpoint. Clinicians must weigh efficacy and safety outcomes in decision-making on thromboprophylaxis. SUMMARY: Background Among acutely ill hospitalized medical patients, extended-duration thromboprophylaxis reduces the risk of venous thromboembolism (VTE), but some pharmacologic strategies have been associated with greater risks of major bleeding, thereby offsetting the net clinical benefit (NCB). Methods To assess the risk-benefit profile of anticoagulation regimens, a previously described bivariate method that does not assume a linear risk-benefit tradeoff and can accommodate different margins for efficacy and safety was performed to simultaneously assess efficacy (symptomatic VTE) and safety (major bleeding) on the basis of data from four randomized controlled trials of extended-duration (30-46 days) versus standard-duration (6-14 days) thromboprophylaxis among 28 227 patients (EXCLAIM, ADOPT, MAGELLAN and APEX trials). Results Extended thromboprophylaxis with full-dose betrixaban (80 mg once daily) was superior in efficacy and non-inferior in safety to standard-duration enoxaparin, and showed a significantly favorable NCB, with a risk difference of - 0.51% (- 0.89% to - 0.10%) in the bivariate outcome. Extended enoxaparin was superior in efficacy and inferior in safety (bivariate outcome: 0.03% [- 0.37% to 0.43%]), whereas apixaban and rivaroxaban were non-inferior in efficacy and inferior in safety (- 0.20% [- 0.49% to 0.17%] and 0.23% [- 0.16% to 0.69%], respectively). Reduced-dose betrixaban did not show a significant difference in either efficacy or safety (0.41% [- 0.85% to 1.94%]). Conclusions In a bivariate analysis that assumes non-linear risk-benefit tradeoffs, extended prophylaxis with full-dose betrixaban was superior to standard-duration enoxaparin, whereas other regimens failed to simultaneously achieve both superiority and non-inferiority with respect to symptomatic VTE and major bleeding in the management of acutely ill hospitalized medical patients.


Subject(s)
Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Hemorrhage/chemically induced , Hospitalization , Venous Thromboembolism/prevention & control , Acute Disease , Benzamides/administration & dosage , Benzamides/adverse effects , Clinical Decision-Making , Clinical Trials, Phase III as Topic , Clinical Trials, Phase IV as Topic , Drug Administration Schedule , Enoxaparin/administration & dosage , Enoxaparin/adverse effects , Humans , Multivariate Analysis , Nonlinear Dynamics , Pyrazoles/administration & dosage , Pyrazoles/adverse effects , Pyridines/administration & dosage , Pyridines/adverse effects , Pyridones/administration & dosage , Pyridones/adverse effects , Randomized Controlled Trials as Topic , Risk Assessment , Risk Factors , Rivaroxaban/administration & dosage , Rivaroxaban/adverse effects , Time Factors , Treatment Outcome , Venous Thromboembolism/blood , Venous Thromboembolism/diagnosis , Venous Thromboembolism/etiology
14.
J Immunol ; 198(3): 1081-1092, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28031336

ABSTRACT

Individuals suffering from autoimmune disorders possess a hyperactive cellular phenotype where tolerance to self-antigens is lost. Autophagy has been implicated in both the induction and prevention of autoimmunity, and modulators of this cellular recycling process hold high potential for the treatment of autoimmune diseases. In this study, we determine the effects of a loss of autophagy in dendritic cells (DCs), as well as both B cells and DCs, in a TLR7-mediated model of autoimmunity, similar to systemic lupus erythematosus, where both cell types are critical for disease. Although a loss of DC autophagy slowed disease, the combined loss of autophagy in both cell types resulted in a lethal sepsis-like environment, which included tissue inflammation and hyperproduction of inflammasome-associated cytokines. Ablation of B cell signaling reversed this phenotype, indicating that activation of these cells is an essential step in disease induction. Thus, autophagy plays a dichotomous role in this model of disease.


Subject(s)
Autoimmunity , Autophagy/physiology , B-Lymphocytes/physiology , Dendritic Cells/physiology , Inflammation/etiology , Membrane Glycoproteins/physiology , Toll-Like Receptor 7/physiology , Animals , Interleukin-18/biosynthesis , Lupus Erythematosus, Systemic/etiology , Lymphadenopathy/etiology , Mice , Mice, Inbred C57BL , Splenomegaly/etiology
15.
Brachytherapy ; 15(2): 185-90, 2016.
Article in English | MEDLINE | ID: mdl-26796601

ABSTRACT

PURPOSE: Within a multifraction high-dose-rate vaginal cuff brachytherapy course, we determined if individual variations in organ at risk (OAR) volume and cylinder insertion geometry (CIG) impacted dose and whether planned minus fractional (P - F) differences led to a discrepancy between planned dose and delivered dose. METHODS AND MATERIALS: We analyzed vaginal cuff brachytherapy applications from consecutive patients treated with three fractions of 5 Gy after each undergoing a planning CT and three repeat fractional CTs (fCTs). Rectal and bladder D2ccs and volumes were recorded in addition to the x (in relationship to midplane) and y (in relationship to the table) angles of CIG. Paired t-tests and multiple regression analyses were performed. RESULTS: Twenty-seven patients were identified. In comparing the planning CT vs. mean fCT rectal volumes, bladder volumes, x angles, and y angles, only bladder volume was significantly different (planned volume higher, t = 2.433, p = 0.017). The cumulative mean planned OAR D2cc vs. delivered D2cc was only significantly different for the bladder (planned dose lower, t = -2.025, p = 0.053). Regression analysis revealed planned rectal D2cc (p < 0.0003) and a positive (posterior) y insertion angle (p = 0.015) to significantly impact delivered rectal D2cc. Additionally, P - F rectal volume (p = 0.037) was significant in determining rectal delivered dose. CONCLUSIONS: A more posterior y angle of insertion was found to increase rectal D2cc leading us to believe that angling the vaginal cylinder anteriorly may reduce rectal dose without significantly increasing bladder dose. Although attention should be paid to OAR volume and CIG to minimize OAR dose, the clinical significance of P - F changes remains yet to be shown.


Subject(s)
Brachytherapy/methods , Endometrial Neoplasms/radiotherapy , Organs at Risk/anatomy & histology , Rectum/anatomy & histology , Urinary Bladder/anatomy & histology , Brachytherapy/adverse effects , Dose Fractionation, Radiation , Female , Humans , Organ Size , Organs at Risk/diagnostic imaging , Radiation Dosage , Radiotherapy Planning, Computer-Assisted , Rectum/diagnostic imaging , Tomography, X-Ray Computed , Urinary Bladder/diagnostic imaging , Vagina
17.
Autophagy ; 11(7): 1010-24, 2015.
Article in English | MEDLINE | ID: mdl-26120731

ABSTRACT

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, defined by loss of B cell self-tolerance that results in production of antinuclear antibodies (ANA) and chronic inflammation. While the initiating events in lupus development are not well defined, overexpression of the RNA-recognizing toll-like receptor (TLR)7 has been linked to SLE in humans and mice. We postulated that autophagy plays an essential role in TLR7 activation of B cells for the induction of SLE by delivering RNA ligands to the endosomes, where this innate immune receptor resides. To test this hypothesis, we compared SLE development in Tlr7 transgenic (Tg) mice with or without B cell-specific ablation of autophagy (Cd19-Cre Atg5(f/f)). We observed that in the absence of B cell autophagy the 2 hallmarks of SLE, ANA and inflammation, were eliminated, thus curing these mice of lupus. This was also evident in the significantly extended survival of the autophagy-deficient mice compared to Tlr7.1 Tg mice. Furthermore, glomerulonephritis was ameliorated, and the serum levels of inflammatory cytokines in the knockout (KO) mice were indistinguishable from those of control mice. These data provide direct evidence that B cells require TLR7-dependent priming through an autophagy-dependent mechanism before autoimmunity is induced, thereafter involving many cell types. Surprisingly, hyper-IgM production persisted in Tlr7.1 Tg mice in the absence of autophagy, likely involving a different activation pathway than the production of autoantibodies. Furthermore, these mice still presented with anemia, but responded with a striking increase in extramedullary hematopoiesis (EMH), possibly due to the absence of pro-inflammatory cytokines.


Subject(s)
Autoimmunity/immunology , Autophagy/immunology , B-Lymphocytes/cytology , B-Lymphocytes/immunology , Inflammation/immunology , Inflammation/pathology , Membrane Glycoproteins/metabolism , Toll-Like Receptor 7/metabolism , Animals , Autoantibodies/immunology , Autophagy-Related Protein 5 , Breeding , Cytokines/metabolism , Dendritic Cells/metabolism , Genotype , Hematopoiesis , Immunoglobulin M/metabolism , Liver/metabolism , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/pathology , Macrophages/metabolism , Membrane Glycoproteins/agonists , Mice, Inbred C57BL , Mice, Knockout , Microtubule-Associated Proteins/metabolism , Signal Transduction/immunology , Spleen/metabolism , Toll-Like Receptor 7/agonists
18.
Z Naturforsch C J Biosci ; 69(7-8): 276-82, 2014.
Article in English | MEDLINE | ID: mdl-25265847

ABSTRACT

A new triterpene diastereomer, 1, of the previously reported 3beta,6beta,19alpha-trihydroxy-urs-12-en-28-oic acid-24-carboxylic acid methyl ester was obtained from the stem bark of Omphalocarpum elatum Miers (Sapotaceae) along with a-amyrin acetate (2), spinasterol (3), spinasterol 3-O-beta-D-glucopyranoside (4), and tormentic acid (5). The structures of the isolates were established on the basis of NMR and mass spectrometric data and by comparison with those previously reported in the literature. Compound 1 showed weak antibacterial activity against E. aerogenes ATCC13048 and EA3, K. pneumoniae ATCC29916, and P aeruginosa; it also displayed moderate cytotoxicity against CCRF-CEM, CEM/ADR5000, and MDA-MB231 cells.


Subject(s)
Sapotaceae/chemistry , Triterpenes/isolation & purification , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure , Spectrometry, Mass, Electrospray Ionization , Triterpenes/chemistry
19.
Genet Mol Res ; 13(2): 2683-90, 2014 Apr 08.
Article in English | MEDLINE | ID: mdl-24782057

ABSTRACT

White matter lesion (WML) in magnetic resonance imaging is commonly observed in patients with cerebral small vessel disease (SVD), but the pathological mechanism of WML in SVD is still unclear. We observed the metabolism and microscopic anatomy of white matter in SVD patients. Twelve subjects clinically diagnosed with SVD and 6 normal control subjects were examined with magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI). The white matter at the centrum semiovale level was selected as the region of interest (ROI). The ROI metabolism parameters, including N-acetyl-l-aspartic acid (NAA), creatine (Cr), and choline (Cho) were measured by MRS. Microscopic parameters such as mean diffusion (MD) and fractional anisotropy (FA) in ROI were obtained by DTI. Compared with the normal control group, bilateral MD values in the SVD group were significantly elevated, whereas bilateral FA values in SVD were decreased, but the difference was not statistically significant. Additionally, NAA/Cho, Cho/Cr, and NAA/Cr showed no significant statistical differences. Our study suggests that the mechanisms of the SVD cognitive impairment are related to damage of the white matter structures rather than to brain metabolism.


Subject(s)
Cerebral Small Vessel Diseases/diagnostic imaging , Diffusion Tensor Imaging , Magnetic Resonance Spectroscopy , White Matter/pathology , Adult , Aged , Aged, 80 and over , Brain/diagnostic imaging , Cerebral Small Vessel Diseases/pathology , Cognition Disorders/genetics , Cognition Disorders/pathology , Female , Humans , Male , Middle Aged , Radiography , White Matter/diagnostic imaging
20.
Diabetes ; 61(6): 1500-8, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22474026

ABSTRACT

Cytokines are upregulated in prediabetes, but their relationship with Enterovirus (EV) infection and development of islet autoimmunity is unknown. Cytokines (n = 65) were measured using Luminex xMAP technology in a nested case-control study of 67 children with a first-degree relative with type 1 diabetes: 27 with islet autoantibodies (Ab(+)) and 40 age-matched persistently autoantibody negative (Ab(-)) control subjects. Of 74 samples, 37 (50%) were EV-PCR(+) in plasma and/or stool (EV(+)) and the remainder were negative for EV and other viruses (EV(-)). Fifteen cytokines, chemokines, and growth factors were elevated (P ≤ 0.01) in Ab(+) versus Ab(-) children (interleukin [IL]-1ß, IL-5, IL-7, IL-12(p70), IL-16, IL-17, IL-20, IL-21, IL-28A, tumor necrosis factor-α, chemokine C-C motif ligand [CCL]13, CCL26, chemokine C-X-C motif ligand 5, granulocyte-macrophage colony-stimulating factor, and thrombopoietin); most have proinflammatory effects. In EV(+) versus EV(-) children, IL-10 was higher (P = 0.005), while IL-21 was lower (P = 0.008). Cytokine levels did not differ between Ab(+)EV(+) and Ab(+)EV(-) children. Heat maps demonstrated clustering of some proinflammatory cytokines in Ab(+) children, suggesting they are coordinately regulated. In conclusion, children with islet autoimmunity demonstrate higher levels of multiple cytokines, consistent with an active inflammatory process in the prediabetic state, which is unrelated to coincident EV infection. Apart from differences in IL-10 and IL-21, EV infection was not associated with a specific cytokine profile.


Subject(s)
Cytokines/blood , Diabetes Mellitus, Type 1/immunology , Enterovirus Infections/immunology , Prediabetic State/immunology , Autoimmunity , Case-Control Studies , Child, Preschool , Diabetes Mellitus, Type 1/blood , Enterovirus Infections/blood , Female , Humans , Infant , Male , Prediabetic State/blood , Prospective Studies
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