69 research outputs found
Temporal profile of serum mitochondrial DNA (mtDNA) in patients with aneurysmal subarachnoid hemorrhage (aSAH)
Aneurysmal subarachnoid hemorrhage (aSAH) is a highly complex disease. Majority of aSAH survivors confront post-SAH complications including cerebral vasospasm (CVS) and delayed cerebral ischemia (DCI) that mainly influence the clinical outcome. Tissue damage during early brain injury may lead to release of damage associated molecular pattern molecules (DAMPs) that may initiate and sustain inflammation during the course of aSAH through activation of pattern recognition receptors. Mitochondrial DNA (mtDNA) due to unmethylated CpG motifs acts as a DAMP via binding to toll-like receptor-9. The aim of this study was to investigate the cell free circulating mtDNA in the systemic circulation of aSAH patients and its association with post-SAH complications and clinical outcome. The DNA was extracted from the serum of 80 aSAH patients at days 1, 3, 5, 7, 9, 11, 13 and from 18 healthy controls. Three representative mitochondrial gene fragments including Cytochrome B (CytB), D-Loop and Cytochrome c oxidase subunit-1 (COX-1) were quantified using a Taqman-probes based qPCR. Levels of mtDNA were quantified from standard curves generated using mtDNA extracted from HepG2 cell mitochondria. Clinical outcome of the patients was assessed by Glasgow outcome scale (GOS) and modified Rankin scale (mRS). Clinical data and post-SAH complications were recorded from patient's record file. Serum D-Loop and COX-1 were significantly elevated early after aSAH and remained high over first 2 weeks. CytB levels were however, initially unchanged but elevated later at day 7 as compared to healthy controls. Cumulative levels measured over two weeks showed significant correlations with post-SAH complications including a negative correlation of D-Loop with pneumonia infection, hydrocephalus and occurrence of epilepsy, a positive correlation of Cyt B with occurrence of CVS and a negative correlation of COX-1 with occurrence of systemic infections and seizures. Cumulative D-Loop values negatively correlated with clinical outcome. Our data suggest that mtDNA may directly or indirectly influence post-SAH complications and clinical outcome.Peer reviewe
Role of Damage Associated Molecular Pattern Molecules (DAMPs) in Aneurysmal Subarachnoid Hemorrhage (aSAH)
Aneurysmal subarachnoid hemorrhage (aSAH) represents only a small portion of all strokes, but accounts for almost half of the deaths caused by stroke worldwide. Neurosurgical clipping and endovascular coiling can successfully obliterate the bleeding aneurysms, but ensuing complications such as cerebral vasospasm, acute and chronic hydrocephalus, seizures, cortical spreading depression, delayed ischemic neurological deficits, and delayed cerebral ischemia lead to poor clinical outcomes. The mechanisms leading to these complications are complex and poorly understood. Early brain injury resulting from transient global ischemia can release molecules that may be critical to initiate and sustain inflammatory response. Hence, the events during early brain injury can influence the occurrence of delayed brain injury. Since the damage associated molecular pattern molecules (DAMPs) might be the initiators of inflammation in the pathophysiology of aSAH, so the aim of this review is to highlight their role in the context of aSAH from diagnostic, prognostic, therapeutic, and drug therapy monitoring perspectives. DAMPs represent a diverse and a heterogenous group of molecules derived from different compartments of cells upon injury. Here, we have reviewed the most important DAMPs molecules including high mobility group box-1 (HMGB1), S100B, hemoglobin and its derivatives, extracellular matrix components, IL-1α, IL-33, and mitochondrial DNA in the context of aSAH and their role in post-aSAH complications and clinical outcome after aSAH.Peer reviewe
Elevated Systemic IL-10 Levels Indicate Immunodepression Leading to Nosocomial Infections after Aneurysmal Subarachnoid Hemorrhage (SAH) in Patients
Background: Aneurysmal subarachnoid hemorrhage (SAH) is a highly complex disease with very high mortality and morbidity. About one-third of SAH patients suffer from systemic infections, predominantly pneumonia, that can contribute to excess mortality after SAH. Immunodepression is probably the most important mechanism leading to infections. Interleukin-10 (IL-10) is a master regulator of immunodepression, but it is still not clear if systemic IL-10 levels contribute to immunodepression, occurrence of infections and clinical outcome after SAH. Methods: This explorative study included 76 patients with SAH admitted to our neurointensive care unit within 24 h after ictus. A group of 24 patients without any known intracranial pathology were included as controls. Peripheral venous blood was withdrawn on day 1 and day 7 after SAH. Serum was isolated by centrifugation and stored at â80 °C until analysis. Serum IL-10 levels were determined by enzyme-linked immunoassay (ELISA). Patient characteristics, post-SAH complications and clinical outcome at discharge were retrieved from patientsâ record files. Results: Serum IL-10 levels were significantly higher on day 1 and day 7 in SAH patients compared to controls. Serum IL-10 levels were significantly higher on day 7 in patients who developed any kind of infection, cerebral vasospasm (CVS) or chronic hydrocephalus. Serum IL-10 levels were significantly higher in SAH patients discharged with poor clinical outcome (modified Rankin Scale (mRS) 3â6 or Glasgow Outcome Scale (GOS) 1â3). Conclusion: Serum IL-10 might be an additional useful parameter along with other biomarkers to predict post-SAH infections
<Abstract of Published Report>Biodegradable Nanoparticles for Targeted Ddrug Delivery in Treatment of Inflammatory Bowel Disease.
A presynaptic phosphosignaling hub for lasting homeostatic plasticity
Stable function of networks requires that synapses adapt their strength to levels of neuronal activity, and failure to do so results in cognitive disorders. How such homeostatic regulation may be implemented in mammalian synapses remains poorly understood. Here we show that the phosphorylation status of several positions of the active-zone (AZ) protein RIM1 are relevant for synaptic glutamate release. Position RIMS1045 is necessary and sufficient for expression of silencing-induced homeostatic plasticity and is kept phosphorylated by serine arginine protein kinase 2 (SRPK2). SRPK2-induced upscaling of synaptic release leads to additional RIM1 nanoclusters and docked vesicles at the AZ and is not observed in the absence of RIM1 and occluded by RIMS1045E. Our data suggest that SRPK2 and RIM1 represent a presynaptic phosphosignaling hub that is involved in the homeostatic balance of synaptic coupling of neuronal networks
Multiparticulate systems containing 5-aminosalicylic acid for the treatment of inflammatory bowel disease
In recent years, many achievements have been realized in the therapy of inflammatory bowel disease (IBD) although its etiology remains unknown. Thus IBD treatment is symptomatic and targets general inflammatory mechanisms. Oral formulations containing 5-aminosalicylic acid (5-ASA) have become the standard therapy for mild-to-moderate IBD
Les systÚmes microparticulaires pour la libération colonique
La maladie de Crohn et la rectocolite hĂ©morragique font partie des maladies inflammatoires chroniques de l'intestin (MICI). Le principal objectif des traitements anti-inflammatoires est de favoriser la dĂ©livrance du principe actif localement, spĂ©cifiquement sur les zones enflammĂ©es et de limiter les effets indĂ©sirables. Ainsi, plusieurs systĂšmes Ă libĂ©ration colonique de molĂ©cules actives ont Ă©tĂ© dĂ©veloppĂ©s. Parmi eux, les pellets prĂ©sentent de nombreux avantages par rapport aux formes solides unitaires conventionnelles. Dans un premier temps, des pellets comptant une substance anti-inflammatoire naturelle et nutritive, la rutine, ont Ă©tĂ© dĂ©veloppĂ©s. L'intĂ©rĂȘt de cette molĂ©cule est de rĂ©duire considĂ©rablement les effets secondaires qui constituent un vĂ©ritable problĂšme dans les traitements actuels des MICI. Les pellets ont Ă©tĂ© enrobĂ© avec les polysaccharides naturels se dĂ©gradant avec la flore colonique. Les Ă©tudes in vitro ont dĂ©montrĂ© une libĂ©ration minimale du principe actif au niveau de l'estomac et du petit intestin. Par contre, une libĂ©ration rapide et totale a Ă©tĂ© observĂ©e lors de l'exposition des pellets dans les conditions du milieu colonique. Les rĂ©sultats des tests in vivo ont dĂ©montrĂ© que la rutine a attĂ©nuĂ© considĂ©rablement l'inflammation au niveau de colon et les pellets enrobĂ©s ont Ă©tĂ© aussi efficaces que les pellets d'acide 5-aminosalicylique (5-ASA) commercialisĂ©s. L'administration orale de rutine via les pellets enrobĂ©s et prĂ©parĂ©s avec le chitosan semble ĂȘtre une approche prometteuse, permettant la libĂ©ration du principe actif au niveau des zones enflammĂ©es, pour le traitement des MICI tout en rĂ©duisant les effets secondaires. Le deuxiĂšme but de notre travail Ă©tait d'Ă©lucider l'impact du chitosan, un polymĂšre mucoadhĂ©sif, sur l'efficacitĂ© thĂ©rapeutique. Les pellets de 5-ASA ont Ă©tĂ© prĂ©parĂ©s Ă partir de cellulose microcristalline avec ou sans chitosan. Un enrobage constituĂ© d'un polymĂšre pH dĂ©pendant,1' EudragitÂź FS, a ensuite Ă©tĂ© rĂ©alisĂ© autour du noyau. Les tests de dissolution ont montrĂ© que le principe actif n'Ă©tait pas libĂ©rĂ© du pellet aprĂšs 2 h en milieu acide. En revanche,la libĂ©ration Ă©tait rapide dans un milieu simulant l'environnement colonique. Les tests ex vivo avec les pellets contenant le chitosan ont montrĂ© des propriĂ©tĂ©s mucoadhĂ©sives importantes qui ont Ă©tĂ© confirmĂ©es par la concentration Ă©levĂ©e du mĂ©tabolite de 5-ASA dans les tissus coloniques des rats. De plus, nous avons a dĂ©montrĂ© que les pellets permettaient d'attĂ©nuer de façon significative l'inflammation du cĂŽlon. Ainsi, les pellets bioadhĂ©sifs enrobĂ©s possĂšdent des propriĂ©tĂ©s bĂ©nĂ©fiques supplĂ©mentaires pour la libĂ©ration du 5-ASA au niveau du cĂŽlon par rapport Ă des formes multidoses commercialisĂ©es pour le traitement des MICI.Crohn's disease and ulcerative colitis are two related but distinct chronic inflammatory disorders of gastrointestinal tract (GIT), commonly denoted as inflammatory bowel disease(IBD). The main goal of the anti-inflammatory treatment of this disorder is to achieve maximal drug concentration in inflamed area and reduce systemic adverse effects. For this purpose several colon-spĂ©cifie drug delivery systems have been investigated. In addition, the design of pellets as oral drug delivery systems may provide many advantages over single unit preparations and thus improve patient compliance. It is well known that most existing treatments of IBD are associated with significant side effects and for this reason the formulation with a " food like " composition was designed. In the first part of our study, therapeutic efficiency of rutin/chitosan pellets with coatings based on natural polysaccharides degraded by colonie microbiota compared to commercialized 5-aminosalicylic acid (5-ASA) pellets was investigated. Release profiles ofcoated pellets showed a minimal drug release in simulated stomach and small intestine following by rapid drug release upon exposure to the colonie fluid. The results from in vivo testing showed that rutin attenuated efficiently inflammation in the colon and coated pellets were as effective as 5-ASA pellets in mitigating experimental colitis. The studies demonstrated that rutin administration via chitosan core coated pellets seems to be apromising approach for colon-specific delivery since they could interact easily with the mucin layer and deliver drug especially to the inflamed colonie area to relieve symptoms of IBD omitting side effects related to conventional treatment. The second objective of this thesis was to explore the impact of additional mucoadhesive polymer chitosan in the pellets core on the therapeutic efficiency. For this purpose, 5-ASA loaded pellets were produced by extrusion/spheronisation method and subsequently coated with pH-sensitive polymer EudragitÂź FS. No drug release at pH 1.2within 2 h, and release as intended in the simulated distal ileum and colon was observed. Chitosan-core pellets showed efficient mucoadhesive properties in ex vivo bioadhesion testing which were also confirmed by increased concentration of 5-ASA metabolite in the colonie tissues in rats. The pellets were tested in preexisting colitis and the results revealed significant attenuation of the colonie inflammation. We can conclude, that bioadhesive chitosan-corepellets showed additional beneficial properties for colonie 5-ASA delivery in the treatment of IBD over marketed dosage formulation.BESANCON-Bib. Electronique (250560099) / SudocSudocFranceF
Muscle Tissue as a Surrogate for In Vitro Drug Release Testing of Parenteral Depot Microspheres
Despite the importance of drug release testing of parenteral depot formulations, the current in vitro methods still require ameliorations in biorelevance. We have investigated here the use of muscle tissue components to better mimic the intramuscular administration. For convenient handling, muscle tissue was used in form of a freeze-dried powder, and a reproducible process of incorporation of tested microspheres to an assembly of muscle tissue of standardized dimensions was successfully developed. Microspheres were prepared from various grades of poly(lactic-co-glycolic acid) (PLGA) or ethyl cellulose, entrapping flurbiprofen, lidocaine, or risperidone. The deposition of microspheres in the muscle tissue or addition of only isolated lipids into the medium accelerated the release rate of all model drugs from microspheres prepared from ester-terminated PLGA grades and ethyl cellulose, however, not from the acid-terminated PLGA grades. The addition of lipids into the release medium increased the solubility of all model drugs; nonetheless, also interactions of the lipids with the polymer matrix (ad- and absorption) might be responsible for the faster drug release. As the in vivo drug release from implants is also often faster than in simple buffers in vitro, these findings suggest that interactions with the tissue lipids may play an important role in these still unexplained observations
CRISPR/Cas9 Delivery Potentials in Alzheimerâs Disease Management: A Mini Review
Alzheimer’s disease (AD) is the most common dementia disorder. While genetic mutations account for only 1% of AD cases, sporadic AD resulting from a combination of genetic and risk factors constitutes >90% of the cases. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated protein (Cas9) is an impactful gene editing tool which identifies a targeted gene sequence, creating a double-stranded break followed by gene inactivation or correction. Although CRISPR/Cas9 can be utilized to irreversibly inactivate or correct faulty genes in AD, a safe and effective delivery system stands as a challenge against the translation of CRISPR therapeutics from bench to bedside. While viral vectors are efficient in CRISPR/Cas9 delivery, they might introduce fatal side effects and immune responses. As non-viral vectors offer a better safety profile, cost-effectiveness and versatility, they can be promising for the in vivo delivery of CRISPR/Cas9 therapeutics. In this minireview, we present an overview of viral and non-viral vector based CRISPR/Cas9 therapeutic strategies that are being evaluated on pre-clinical AD models. Other promising non-viral vectors that can be used for genome editing in AD, such as nanoparticles, nanoclews and microvesicles, are also discussed. Finally, we list the formulation and technical aspects that must be considered in order to develop a successful non-viral CRISPR/Cas9 delivery vehicle
Nanotechnology as a Platform for the Development of Injectable Parenteral Formulations: A Comprehensive Review of the Know-Hows and State of the Art
Within recent decades, the development of nanotechnology has made a significant contribution to the progress of various fields of study, including the domains of medical and pharmaceutical sciences. A substantially transformed arena within the context of the latter is the development and production of various injectable parenteral formulations. Indeed, recent decades have witnessed a rapid growth of the marketed and pipeline nanotechnology-based injectable products, which is a testimony to the remarkability of the aforementioned contribution. Adjunct to the ability of nanomaterials to deliver the incorporated payloads to many different targets of interest, nanotechnology has substantially assisted to the development of many further facets of the art. Such contributions include the enhancement of the drug solubility, development of long-acting locally and systemically injectable formulations, tuning the onset of the drugâs release through the endowment of sensitivity to various internal or external stimuli, as well as adjuvancy and immune activation, which is a desirable component for injectable vaccines and immunotherapeutic formulations. The current work seeks to provide a comprehensive review of all the abovementioned contributions, along with the most recent advances made within each domain. Furthermore, recent developments within the domains of passive and active targeting will be briefly debated
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