scholarly journals Probiotics combined with rifaximin influence the neurometabolic changes in a rat model of type C HE

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Emmanuelle Flatt ◽  
Valérie A. McLin ◽  
Olivier Braissant ◽  
Katarzyna Pierzchala ◽  
Paola Mastromarino ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Brain Metabolism ◽  
Treatment Options ◽  
Multimodal Approach ◽  
Ultra High Field ◽  
Neuropsychiatric Disease ◽  
Important Challenge ◽  
Type C ◽  
The Brain

AbstractType C hepatic encephalopathy (HE) is a neuropsychiatric disease caused by chronic liver disease. Management of type C HE remains an important challenge because treatment options are limited. Both the antibiotic rifaximin and probiotics have been reported to reduce the symptoms of HE, but longitudinal studies assessing their effects on brain metabolism are lacking and the molecular mechanisms underpinning their effects are not fully understood. Therefore, we evaluated in detail the effects of these different treatments on the neurometabolic changes associated with type C HE using a multimodal approach including ultra-high field in vivo 1H MRS. We analyzed longitudinally the effect of rifaximin alone or in combination with the probiotic Vivomixx on the brain metabolic profile in the hippocampus and cerebellum of bile duct ligated (BDL) rats, an established model of type C HE. Overall, while rifaximin alone appeared to induce no significant effect on the neurometabolic profile of BDL rats, its association with the probiotic resulted in more attenuated neurometabolic alterations in BDL rats followed longitudinally (i.e. a smaller increase in Gln and milder decrease in Glu and Cr levels). Given that both rifaximin and some probiotics are used in the treatment of HE, the implications of these findings may be clinically relevant.

scholarly journals Unraveling the neurotoxicity of titanium dioxide nanoparticles: focusing on molecular mechanisms

2016 ◽  
Vol 7 ◽  
pp. 645-654 ◽  
Author(s):  
Bin Song ◽  
Yanli Zhang ◽  
Jia Liu ◽  
Xiaoli Feng ◽  
Ting Zhou ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Titanium Dioxide ◽  
Molecular Mechanisms ◽  
Titanium Dioxide Nanoparticles ◽  
Brain Dysfunction ◽  
In Vivo Studies ◽  
Cell Components ◽  
New Perspective ◽  
The Brain

Titanium dioxide nanoparticles (TiO2 NPs) possess unique characteristics and are widely used in many fields. Numerous in vivo studies, exposing experimental animals to these NPs through systematic administration, have suggested that TiO2 NPs can accumulate in the brain and induce brain dysfunction. Nevertheless, the exact mechanisms underlying the neurotoxicity of TiO2 NPs remain unclear. However, we have concluded from previous studies that these mechanisms mainly consist of oxidative stress (OS), apoptosis, inflammatory response, genotoxicity, and direct impairment of cell components. Meanwhile, other factors such as disturbed distributions of trace elements, disrupted signaling pathways, dysregulated neurotransmitters and synaptic plasticity have also been shown to contribute to neurotoxicity of TiO2 NPs. Recently, studies on autophagy and DNA methylation have shed some light on possible mechanisms of nanotoxicity. Therefore, we offer a new perspective that autophagy and DNA methylation could contribute to neurotoxicity of TiO2 NPs. Undoubtedly, more studies are needed to test this idea in the future. In short, to fully understand the health threats posed by TiO2 NPs and to improve the bio-safety of TiO2 NPs-based products, the neurotoxicity of TiO2 NPs must be investigated comprehensively through studying every possible molecular mechanism.

TMOD-02. GENERATION OF A NOVEL MOUSE MODEL FOR BRAIN TUMORS OF THE DNA METHYLATION CLASS “GBM MYCN”

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi215-vi216
Author(s):  
Melanie Schoof ◽  
Carolin Göbel ◽  
Dörthe Holdhof ◽  
Sina Al-Kershi ◽  
Ulrich Schüller
Keyword(s):  
Dna Methylation ◽  
Brain Tumors ◽  
Molecular Mechanisms ◽  
Treatment Options ◽  
Tumor Development ◽  
Model Systems ◽  
Preclinical Research ◽  
Human Gbm

Abstract DNA methylation based classification of brain tumors has revealed a high heterogeneity between tumors and led to the description of multiple distinct subclasses. The increasing subdivision of tumors can help to understand molecular mechanisms of tumor development and to improve therapy if appropriate model systems for preclinical research are available. Multiple recent publications have described a subgroup of pediatric glioblastoma which is clearly separable from other pediatric and adult glioblastoma in its DNA methylation profile (GBM MYCN). Many cases in this group are driven by MYCN amplifications and harbor TP53 mutations. These tumors almost exclusively occur in children and were further described as highly aggressive with a median overall survival of only 14 months. In order to further investigate the biology and treatment options of these tumors, we generated hGFAP-cre::TP53 Fl/Fl ::lsl-MYCN mice. These mice carry a loss of TP53 and show aberrant MYCN expression in neural precursors of the central nervous system. The animals develop large forebrain tumors within the first 80 days of life with 100 % penetrance. These tumors resemble human GBM MYCN tumors histologically and are sensitive to AURKA and ATR inhibitors in vitro. We believe that further characterization of the model and in vivo treatment studies will pave the way to improve treatment of patients with these highly aggressive tumors.

Model construction of Niemann-Pick type C disease in zebrafish

2018 ◽  
Vol 399 (8) ◽  
pp. 903-910 ◽  
Author(s):  
Yusheng Lin ◽  
Xiaolian Cai ◽  
Guiping Wang ◽  
Gang Ouyang ◽  
Hong Cao
Keyword(s):  
Molecular Mechanisms ◽  
Treatment Options ◽  
Lipid Profiling ◽  
Zebrafish Model ◽  
Reduced Body ◽  
Significant Difference ◽  
Abnormal Accumulation ◽  
Purkinje Cell Death ◽  
Type C ◽  
Niemann Pick

Abstract Niemann-Pick type C disease (NPC) is a rare human disease, with limited effective treatment options. Most cases of NPC disease are associated with inactivating mutations of the NPC1 gene. However, cellular and molecular mechanisms responsible for the NPC1 pathogenesis remain poorly defined. This is partly due to the lack of a suitable animal model to monitor the disease progression. In this study, we used CRISPR to construct an NPC1−/− zebrafish model, which faithfully reproduced the cardinal pathological features of this disease. In contrast to the wild type (WT), the deletion of NPC1 alone caused significant hepatosplenomegaly, ataxia, Purkinje cell death, increased lipid storage, infertility and reduced body length and life span. Most of the NPC1−/− zebrafish died within the first month post fertilization, while the remaining specimens developed slower than the WT and died before reaching 8 months of age. Filipin-stained hepatocytes of the NPC1−/− zebrafish were clear, indicating abnormal accumulation of unesterified cholesterol. Lipid profiling showed a significant difference between NPC1−/− and WT zebrafish. An obvious accumulation of seven sphingolipids was detected in livers of NPC1−/− zebrafish. In summary, our results provide a valuable model system that could identify promising therapeutic targets and treatments for the NPC disease.

scholarly journals Nutraceuticals for the Treatment of Diabetic Retinopathy

Nutrients ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 771 ◽  
Author(s):  
Maria Grazia Rossino ◽  
Giovanni Casini
Keyword(s):  
Diabetic Retinopathy ◽  
Molecular Mechanisms ◽  
Treatment Options ◽  
Vitreoretinal Surgery ◽  
In Vivo Studies ◽  
Early Diabetes ◽  
Advanced Stages ◽  
Endothelial Growth Factor

Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus and is characterized by degeneration of retinal neurons and neoangiogenesis, causing a severe threat to vision. Nowadays, the principal treatment options for DR are laser photocoagulation, vitreoretinal surgery, or intravitreal injection of drugs targeting vascular endothelial growth factor. However, these treatments only act at advanced stages of DR, have short term efficacy, and cause side effects. Treatment with nutraceuticals (foods providing medical or health benefits) at early stages of DR may represent a reasonable alternative to act upstream of the disease, preventing its progression. In particular, in vitro and in vivo studies have revealed that a variety of nutraceuticals have significant antioxidant and anti-inflammatory properties that may inhibit the early diabetes-driven molecular mechanisms that induce DR, reducing both the neural and vascular damage typical of DR. Although most studies are limited to animal models and there is the problem of low bioavailability for many nutraceuticals, the use of these compounds may represent a natural alternative method to standard DR treatments.

Estrogens and progestins: molecular effects on brain cells

2010 ◽  
Vol 4 (3) ◽  
Author(s):  
Paolo Mannella ◽  
Tommaso Simoncini ◽  
Andrea Riccardo Genazzani
Keyword(s):  
Sex Steroids ◽  
Molecular Mechanisms ◽  
Neural Cells ◽  
Protective Effects ◽  
Complete Knowledge ◽  
Molecular Effects ◽  
In Vivo Effects ◽  
The Brain

AbstractSex steroids are known to regulate brain function and their role is so important that several diseases are strictly correlated with the onset of menopause when estrogen-progesterone deficiency makes neural cells much more vulnerable to toxic stimuli. Although in the past years several scientists have focused their studies on in vitro and in vivo effects of sex steroids on the brain, we are still far from complete knowledge. Indeed, contrasting results from large clinical trials have made the entire issue much more complicated. Currently we know that protective effects exerted by sex steroids depend on several factors among which the dose, the health of the cells and the type of molecule being used. In this review, we present an overview of the direct and indirect effects of estrogen and progesterone on the brain with specific focus on the molecular mechanisms by which these molecules act on neural cells.

scholarly journals Using zebrafish larval models to study brain injury, locomotor and neuroinflammatory outcomes following intracerebral haemorrhage

F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 1617
Author(s):  
Siobhan Crilly ◽  
Alexandra Njegic ◽  
Sarah E. Laurie ◽  
Elisavet Fotiou ◽  
Georgina Hudson ◽  
...  
Keyword(s):  
Brain Injury ◽  
Intracerebral Haemorrhage ◽  
Treatment Options ◽  
Brain Cell ◽  
Human Condition ◽  
Fluorescent Reporter ◽  
High Fecundity ◽  
Zebrafish Larvae ◽  
The Brain

Intracerebral haemorrhage (ICH) is a devastating condition with limited treatment options, and current understanding of pathophysiology is incomplete. Spontaneous cerebral bleeding is a characteristic of the human condition that has proven difficult to recapitulate in existing pre-clinical rodent models. Zebrafish larvae are frequently used as vertebrate disease models and are associated with several advantages, including high fecundity, optical translucency and non-protected status prior to 5 days post-fertilisation. Furthermore, other groups have shown that zebrafish larvae can exhibit spontaneous ICH. The aim of this study was to investigate whether such models can be utilised to study the pathological consequences of bleeding in the brain, in the context of pre-clinical ICH research. Here, we compared existing genetic (bubblehead) and chemically inducible (atorvastatin) zebrafish larval models of spontaneous ICH and studied the subsequent disease processes. Through live, non-invasive imaging of transgenic fluorescent reporter lines and behavioural assessment we quantified brain injury, locomotor function and neuroinflammation following ICH. We show that ICH in both zebrafish larval models is comparable in timing, frequency and location. ICH results in increased brain cell death and a persistent locomotor deficit. Additionally, in haemorrhaged larvae we observed a significant increase in macrophage recruitment to the site of injury. Live in vivo imaging allowed us to track active macrophage-based phagocytosis of dying brain cells 24 hours after haemorrhage. Morphological analyses and quantification indicated that an increase in overall macrophage activation occurs in the haemorrhaged brain. Our study shows that in zebrafish larvae, bleeding in the brain induces quantifiable phenotypic outcomes that mimic key features of human ICH. We hope that this methodology will enable the pre-clinical ICH community to adopt the zebrafish larval model as an alternative to rodents, supporting future high throughput drug screening and as a complementary approach to elucidating crucial mechanisms associated with ICH pathophysiology.

scholarly journals Effects of Red Ginseng on Neural Injuries with Reference to the Molecular Mechanisms

J ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 116-127
Author(s):  
Pengxiang Zhu ◽  
Masahiro Sakanaka
Keyword(s):  
Molecular Mechanisms ◽  
Bioactive Molecules ◽  
Red Ginseng ◽  
Promising Candidate ◽  
Neuroprotective Effects ◽  
Chemical Structures ◽  
Brain And Spinal Cord ◽  
The Brain

Red ginseng, as an effective herbal medicine, has been traditionally and empirically used for the treatment of neuronal diseases. Many studies suggest that red ginseng and its ingredients protect the brain and spinal cord from neural injuries such as ischemia, trauma, and neurodegeneration. This review focuses on the molecular mechanisms underlying the neuroprotective effects of red ginseng and its ingredients. Ginsenoside Rb1 and other ginsenosides are regarded as the active ingredients of red ginseng; the anti-apoptotic, anti-inflammatory, and anti-oxidative actions of ginsenosides, together with a series of bioactive molecules relevant to the above actions, appear to account for the neuroprotective effects in vivo and/or in vitro. Moreover, in this review, the possibility is raised that more effective or stable neuroprotective derivatives based on the chemical structures of ginsenosides could be developed. Although further studies, including clinical trials, are necessary to confirm the pharmacological properties of red ginseng and its ingredients, red ginseng and its ingredients could be promising candidate drugs for the treatment of neural injuries.

scholarly journals What Are the Molecular Mechanisms by Which Functional Bacterial Amyloids Influence Amyloid Beta Deposition and Neuroinflammation in Neurodegenerative Disorders?

2020 ◽  
Vol 21 (5) ◽  
pp. 1652 ◽  
Author(s):  
Robert P. Friedland ◽  
Joseph D. McMillan ◽  
Zimple Kurlawala
Keyword(s):  
Amyloid Beta ◽  
Neurodegenerative Disorders ◽  
Innate Immune System ◽  
Molecular Mechanisms ◽  
Innate Immune ◽  
Know How ◽  
Unique Distribution ◽  
The Brain

Despite the enormous literature documenting the importance of amyloid beta (Ab) protein in Alzheimer's disease, we do not know how Ab aggregation is initiated and why it has its unique distribution in the brain. In vivo and in vitro evidence has been developed to suggest that functional microbial amyloid proteins produced in the gut may cross-seed Ab aggregation and prime the innate immune system to have an enhanced and pathogenic response to neuronal amyloids. In this commentary, we summarize the molecular mechanisms by which the microbiota may initiate and sustain the pathogenic processes of neurodegeneration in aging.

Glioblastoma therapeutic approaches were established utilizing contemporary discoveries in delivering medicines to the brain as smart nanoparticles for focused therapy

2021 ◽  
Author(s):  
Moataz Dowaidar
Keyword(s):  
Brain Tumor ◽  
Molecular Mechanisms ◽  
Therapeutic Potential ◽  
Treatment Options ◽  
Brain Targeting ◽  
Cns Drug Delivery ◽  
Blood Brain ◽  
Medication Delivery ◽  
Prospective Application ◽  
The Brain

The blood-brain barrier (primary) and the blood-brain tumor barrier (secondary) are the main barriers for Glioblastoma (GBM) treatment options. Brain design is connected to a critical barrier that restricts medicine delivery to a specific brain region, leaving the rest of the brain without therapeutic chemicals. This requires moving to a different treatment strategy to reach effective therapeutic concentration in brain tumor tissue. Due to more accurate controlled release of medication to the affected area, a continual shift from standard treatment to targeted administration of medication to the brain is attracting more attention these days. GBM's therapeutic approach was established utilizing contemporary discoveries in delivering medicines to the brain as smart nanoparticles for focused therapy. Better knowledge of molecular mechanisms involved in brain targeting and receptor-based therapeutic potential can boost the therapy results. Nonetheless, the most promising technology is still under development, and continual attempts to infer the fundamental process involved in medication delivery will assist hasten nanoparticles' translation into clinical application. Furthermore, numerous complex nanoparticles, including multifunctional smart nanoparticles, have been created to overcome such challenges for CNS drug delivery and their prospective application has been clinically demonstrated or is in the trial phase.

scholarly journals Improved temporal resolution for mapping brain metabolism using functional PET and anatomical MRI knowledge

2020 ◽  
Author(s):  
Viswanath P. Sudarshan ◽  
Shenpeng Li ◽  
Sharna D. Jamadar ◽  
Gary F. Egan ◽  
Suyash P. Awate ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Brain Metabolism ◽  
Visual Stimulation ◽  
Brain Activity ◽  
Brain Activation ◽  
Partial Volume ◽  
Noise Characteristics ◽  
Positron Emission ◽  
The Brain

AbstractFunctional positron emission tomography (fPET) imaging using continuous infusion of [18F]-fluorodeoxyglucose (FDG) is a novel neuroimaging technique to track dynamic glucose utilization in the brain. In comparison to conventional static PET, fPET maintains a sustained supply of glucose in the blood plasma which improves sensitivity to measure dynamic glucose changes in the brain, and enables mapping of dynamic brain activity in task-based and resting-state fPET studies. However, there is a trade-off between temporal resolution and spatial noise due to the low concentration of FDG and the limited sensitivity of multi-ring PET scanners. Images from fPET studies suffer from partial volume errors and residual scatter noise that may cause the cerebral metabolic functional maps to be biased. Gaussian smoothing filters used to denoise the fPET images are suboptimal, as they introduce additional partial volume errors. In this work, a post-processing framework based on a magnetic resonance (MR) Bowsher-like prior was used to improve the spatial and temporal signal to noise characteristics of the fPET images. The performance of the MR guided method was compared with conventional Gaussian filtering using both simulated and in vivo task fPET datasets. The results demonstrate that the MR guided fPET framework reduces the partial volume errors, enhances the sensitivity of identifying brain activation, and improves the anatomical accuracy for mapping changes of brain metabolism in response to a visual stimulation task. The framework extends the use of functional PET to investigate the dynamics of brain metabolic responses for faster presentation of brain activation tasks, and for applications in low dose PET imaging.

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