Antioxidant and Neuroprotective Effects Induced by Cannabidiol and Cannabigerol in Rat CTX-TNA2 Astrocytes and Isolated Cortexes

Cannabidiol (CBD) and cannabigerol (CBG) are Cannabis sativa terpenophenols. Although CBD’s effectiveness against neurological diseases has already been demonstrated, nothing is known about CBG. Therefore, a comparison of the effects of these compounds was performed in two experimental models mimicking the oxidative stress and neurotoxicity occurring in neurological diseases. Rat astrocytes were exposed to hydrogen peroxide and cell viability, reactive oxygen species production and apoptosis occurrence were investigated. Cortexes were exposed to K+ 60 mM depolarizing stimulus and serotonin (5-HT) turnover, 3-hydroxykinurenine and kynurenic acid levels were measured. A proteomic analysis and bioinformatics and docking studies were performed. Both compounds exerted antioxidant effects in astrocytes and restored the cortex level of 5-HT depleted by neurotoxic stimuli, whereas sole CBD restored the basal levels of 3-hydroxykinurenine and kynurenic acid. CBG was less effective than CBD in restoring the levels of proteins involved in neurotransmitter exocytosis. Docking analyses predicted the inhibitory effects of these compounds towards the neurokinin B receptor. Conclusion: The results in the in vitro system suggest brain non-neuronal cells as a target in the treatment of oxidative conditions, whereas findings in the ex vivo system and docking analyses imply the potential roles of CBD and CBG as neuroprotective agents.

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Ocular Toxoplasmosis: Mechanisms of Retinal Infection and Experimental Models

Parasitologia ◽

10.3390/parasitologia1020007 ◽

2021 ◽

Vol 1 (2) ◽

pp. 50-60

Author(s):

Veronica Rodriguez Fernandez ◽

Giovanni Casini ◽

Fabrizio Bruschi

Keyword(s):

Ex Vivo ◽

Cell Damage ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Treatment Strategies ◽

Experimental Models ◽

Ocular Toxoplasmosis ◽

Cell Infection

Ocular toxoplasmosis (OT) is caused by the parasite Toxoplasma gondii and affects many individuals throughout the world. Infection may occur through congenital or acquired routes. The parasites enter the blood circulation and reach both the retina and the retinal pigment epithelium, where they may cause cell damage and cell death. Different routes of access are used by T. gondii to reach the retina through the retinal endothelium: by transmission inside leukocytes, as free parasites through a paracellular route, or after endothelial cell infection. A main feature of OT is the induction of an important inflammatory state, and the course of infection has been shown to be influenced by the host immunogenetics. On the other hand, there is evidence that the T. gondii phenotype also has an impact on the distribution of the pathology in different areas. Although considerable knowledge has been acquired on OT, a deeper knowledge of its mechanisms is necessary to provide new, more targeted treatment strategies. In particular, in addition to in vitro and in vivo experimental models, organotypic, ex vivo retinal explants may be useful in this direction.

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Biochemical and Pharmacological Properties of SANORG 34006, a Potent and Long-Acting Synthetic Pentasaccharide

Blood ◽

10.1182/blood.v91.11.4197 ◽

1998 ◽

Vol 91 (11) ◽

pp. 4197-4205 ◽

Cited By ~ 151

Author(s):

J.M. Herbert ◽

J.P. Hérault ◽

A. Bernat ◽

R.G.M. van Amsterdam ◽

J.C. Lormeau ◽

...

Keyword(s):

Thrombin Generation ◽

Ex Vivo ◽

Thrombus Formation ◽

Factor Xa ◽

Therapeutic Index ◽

Inhibitory Effect ◽

Experimental Models ◽

Treatment And Prevention ◽

Long Acting

Abstract SANORG 34006 is a new sulfated pentasaccharide obtained by chemical synthesis. It is an analog of the “synthetic pentasaccharide” (SR 90107/ ORG 31540) which represents the antithrombin (AT) binding site of heparin. SANORG 34006 showed a higher affinity to human AT than SR 90107/ORG 31540 (kd = 1.4 ± 0.3 v 48 ± 11 nmol/L), and it is a potent and selective catalyst of the inhibitory effect of AT on factor Xa (1,240 ± 15 anti–factor Xa U/mg v850 ± 27 anti-factor Xa U/mg for SR 90107/ORG 31540). In vitro, SANORG 34006 inhibited thrombin generation occurring via both the extrinsic and intrinsic pathway. After intravenous (IV) or subcutaneous (SC) administration to rabbits, SANORG 34006 displayed a long-lasting anti–factor Xa activity and inhibition of thrombin generation (TG) ex vivo. SANORG 34006 was slowly eliminated after IV or SC administration to rats, rabbits, and baboons, showed exceptionally long half-lives (between 9.2 hours in rats and 61.9 hours in baboons), and revealed an SC bioavailability near 100%. SANORG 34006 displayed antithrombotic activity by virtue of its potentiation of the anti–factor Xa activity of AT. It strongly inhibited thrombus formation in experimental models of thromboplastin/stasis-induced venous thrombosis in rats (IV) and rabbits (SC) (ED50values = 40.0 ± 3.4 and 105.0 ± 9.4 nmol/kg, respectively). The duration of its antithrombotic effects closely paralleled the ex vivo anti–factor Xa activity. SANORG 34006 enhanced rt-PA–induced thrombolysis and inhibited accretion of125I-fibrinogen onto a preformed thrombus in the rabbit jugular vein suggesting that concomitant use of SANORG 34006 during rt-PA therapy might be helpful in facilitating thrombolysis and preventing fibrin accretion onto the thrombus under lysis. Contrary to standard heparin, SANORG 34006 did not enhance bleeding in a rabbit ear incision model at a dose that equals 10 times the antithrombotic ED50 in this species and, therefore, exhibited a favorable therapeutic index. We suggest that SANORG 34006 is a promising compound in the treatment and prevention of various thrombotic diseases.

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The effect of kynurenic acid on the synthesis of selected cytokines by murine splenocytes – in vitro and ex vivo studies

Central European Journal of Immunology ◽

10.5114/ceji.2016.58815 ◽

2016 ◽

Vol 1 ◽

pp. 39-46 ◽

Cited By ~ 15

Author(s):

Joanna Małaczewska ◽

Andrzej K. Siwicki ◽

Roman M. Wójcik ◽

Waldemar A. Turski ◽

Edyta Kaczorek

Keyword(s):

Kynurenic Acid ◽

Ex Vivo ◽

Murine Splenocytes

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Models and methods to characterise levonorgestrel release from intradermally administered contraceptives

Drug Delivery and Translational Research ◽

10.1007/s13346-021-01091-5 ◽

2021 ◽

Author(s):

Adnan Al Dalaty ◽

Benedetta Gualeni ◽

Sion A. Coulman ◽

James C. Birchall

Keyword(s):

Ex Vivo ◽

Extraction Procedure ◽

In Vitro Release ◽

Reversed Phase ◽

Experimental Models ◽

Detection Methods ◽

Hormonal Contraceptives ◽

Limit Of Quantification ◽

Long Acting

AbstractMicroneedle (MN)-based technologies have been proposed as a means to facilitate minimally invasive sustained delivery of long-acting hormonal contraceptives into the skin. Intradermal administration is a new route of delivery for these contraceptives and therefore no established laboratory methods or experimental models are available to predict dermal drug release and pharmacokinetics from candidate MN formulations. This study evaluates an in vitro release (IVR) medium and a medium supplemented with ex vivo human skin homogenate (SH) as potential laboratory models to investigate the dermal release characteristics of one such hormonal contraceptive that is being tested for MN delivery, levonorgestrel (LNG), and provides details of an accompanying novel two-step liquid–liquid drug extraction procedure and sensitive reversed-phase HPLC–UV assay. The extraction efficiency of LNG was 91.7 ± 3.06% from IVR medium and 84.6 ± 1.6% from the medium supplemented with SH. The HPLC–UV methodology had a limit of quantification of 0.005 µg/mL and linearity between 0.005 and 25 µg/mL. Extraction and detection methods for LNG were exemplified in both models using the well-characterised, commercially available sustained-release implant (Jadelle®). Sustained LNG release from the implant was detected in both media over 28 days. This study reports for the first time the use of biologically relevant release models and a rapid, reliable and sensitive methodology to determine release characteristics of LNG from intradermally administered long-acting drug delivery systems. Graphical abstract

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Optimising experimental research in respiratory diseases: an ERS statement

European Respiratory Journal ◽

10.1183/13993003.02133-2017 ◽

2018 ◽

Vol 51 (5) ◽

pp. 1702133 ◽

Cited By ~ 42

Author(s):

Philippe Bonniaud ◽

Aurélie Fabre ◽

Nelly Frossard ◽

Christophe Guignabert ◽

Mark Inman ◽

...

Keyword(s):

Experimental Research ◽

Task Force ◽

Ex Vivo ◽

Experimental Models ◽

Chronic Obstructive ◽

Ethical Perspective ◽

Validity Of Results ◽

Use Of Resources ◽

Research Recommendations

Experimental models are critical for the understanding of lung health and disease and are indispensable for drug development. However, the pathogenetic and clinical relevance of the models is often unclear. Further, the use of animals in biomedical research is controversial from an ethical perspective.The objective of this task force was to issue a statement with research recommendations about lung disease models by facilitating in-depth discussions between respiratory scientists, and to provide an overview of the literature on the available models. Focus was put on their specific benefits and limitations. This will result in more efficient use of resources and greater reduction in the numbers of animals employed, thereby enhancing the ethical standards and translational capacity of experimental research.The task force statement addresses general issues of experimental research (ethics, species, sex, age,ex vivoandin vitromodels, gene editing). The statement also includes research recommendations on modelling asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, lung infections, acute lung injury and pulmonary hypertension.The task force stressed the importance of using multiple models to strengthen validity of results, the need to increase the availability of human tissues and the importance of standard operating procedures and data quality.

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Antioxidant and Anti-Inflammatory Effects of Citrus Flavonoid Hesperetin: Special Focus on Neurological Disorders

Antioxidants ◽

10.3390/antiox9070609 ◽

2020 ◽

Vol 9 (7) ◽

pp. 609 ◽

Cited By ~ 2

Author(s):

Amjad Khan ◽

Muhammad Ikram ◽

Jong Ryeal Hahm ◽

Myeong Ok Kim

Keyword(s):

Neurodegenerative Disorders ◽

In Vitro Models ◽

Experimental Models ◽

Special Focus ◽

Neuroprotective Effects ◽

Beneficial Effects ◽

Wide Range ◽

Underlying Mechanisms

Neurodegenerative disorders have emerged as a serious health issue in the current era. The most common neurodegenerative disorders are Alzheimer’s disease (AD), Parkinson’s disease, multiple sclerosis, and amyotrophic lateral sclerosis (ALS). These diseases involve progressive impairment of neurodegeneration and memory impairment. A wide range of compounds have been identified as potential neuroprotective agents against different models of neurodegeneration both in vivo and in vitro. Hesperetin, a flavanone class of citrus flavonoid, is a derivative of hesperidin found in citrus fruits such as oranges, grapes, and lemons. It has been extensively reported that hesperetin exerts neuroprotective effects in experimental models of neurodegenerative diseases. In this systematic review, we have compiled all the studies conducted on hesperetin in both in vivo and in vitro models of neurodegeneration. Here, we have used an approach to lessen the bias in each study, providing a least biased, broad understanding of findings and impartial conclusions of the strength of evidence and the reliability of findings. In this review, we collected different papers from a wide range of journals describing the beneficial effects of hesperetin on animal models of neurodegeneration. Our results demonstrated consistent neuroprotective effects of hesperetin against different models of neurodegeneration. In addition, we have summarized its underlying mechanisms. This study provides the foundations for future studies and recommendations of further mechanistic approaches to conduct preclinical studies on hesperetin in different models.

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Natural Glycoside Salidroside Ameliorates Orthopedic Surgery-Induced Cognitive Dysfunction Through Activating Adenosine 5‘-Monophosphate-Activated Protein Kinase Signaling in Mice

10.21203/rs.3.rs-745010/v1 ◽

2021 ◽

Author(s):

Cai-Long Pan ◽

Guo-Liang Dai ◽

Hui-Wen Zhang ◽

Chen-Yang Zhang ◽

Qing-Hai Meng ◽

...

Keyword(s):

Cognitive Dysfunction ◽

Orthopedic Surgery ◽

Neurological Diseases ◽

Docking Studies ◽

Morris Water Maze Test ◽

Ampk Pathway ◽

Inflammatory Phenotype ◽

Anti Inflammatory

Abstract Background: Perioperative neurocognitive disorders (PND) are the most common postoperative complications with few therapeutic options. Salidroside, a plant-derived compound, has gained increased attention as treatment for various neurological diseases and particularly modifier of microglia-mediated neuroinflammation. However, the effect of salidroside on orthopedic surgery-induced cognitive dysfunction and the underlying mechanisms are largely unknown.Methods: The Morris water maze test was used to investigate potential effects of salidroside in the animal model of tibia fracturing with intramedullary fixation. Therapeutic mechanism and related signaling pathways of salidroside in PND were further investigated with animal tissues and microglial cultures in vitro by molecular biology tests.Results: Here we found that salidroside greatly attenuated cognitive impairment in mice after orthopedic surgery. Neuroinflammation in mouse hippocampus were also attenuated by salidroside. Meanwhile, salidroside treatment induced a switch in microglia polarization to the anti-inflammatory phenotype. In vitro, salidroside suppressed the expression of pro-inflammatory cytokines and induced a switch in microglial phenotype to the anti-inflammatory phenotype. Mechanically, molecular docking studies revealed potential AMPK activation activity of salidroside. And salidroside did up-regulated the AMPK pathway proteins. Moreover, AMPK antagonist abolished the effects of salidroside in vivo and in vitro.Conclusions: Taken together, our results demonstrated that salidroside effectively suppressed PND by suppressing microglia-mediated neuroinflammation through activating AMPK pathway, and it might be a novel therapeutic approach for PND.

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Engineering of a Spider Peptide via Conserved Structure-Function Traits Optimizes Sodium Channel Inhibition In Vitro and Anti-Nociception In Vivo

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.742457 ◽

2021 ◽

Vol 8 ◽

Author(s):

H. Hu ◽

S. E. Mawlawi ◽

T. Zhao ◽

J. R. Deuis ◽

S. Jami ◽

...

Keyword(s):

Structure Function ◽

Visceral Pain ◽

Neurological Diseases ◽

Docking Studies ◽

Voltage Sensor ◽

Voltage Gated ◽

Channel Inhibition ◽

Voltage Sensor Domain

Venom peptides are potent and selective modulators of voltage-gated ion channels that regulate neuronal function both in health and in disease. We previously identified the spider venom peptide Tap1a from the Venezuelan tarantula Theraphosa apophysis that targeted multiple voltage-gated sodium and calcium channels in visceral pain pathways and inhibited visceral mechano-sensing neurons contributing to irritable bowel syndrome. In this work, alanine scanning and domain activity analysis revealed Tap1a inhibited sodium channels by binding with nanomolar affinity to the voltage-sensor domain II utilising conserved structure-function features characteristic of spider peptides belonging to family NaSpTx1. In order to speed up the development of optimized NaV-targeting peptides with greater inhibitory potency and enhanced in vivo activity, we tested the hypothesis that incorporating residues identified from other optimized NaSpTx1 peptides into Tap1a could also optimize its potency for NaVs. Applying this approach, we designed the peptides Tap1a-OPT1 and Tap1a-OPT2 exhibiting significant increased potency for NaV1.1, NaV1.2, NaV1.3, NaV1.6 and NaV1.7 involved in several neurological disorders including acute and chronic pain, motor neuron disease and epilepsy. Tap1a-OPT1 showed increased potency for the off-target NaV1.4, while this off-target activity was absent in Tap1a-OPT2. This enhanced potency arose through a slowed off-rate mechanism. Optimized inhibition of NaV channels observed in vitro translated in vivo, with reversal of nocifensive behaviours in a murine model of NaV-mediated pain also enhanced by Tap1a-OPT. Molecular docking studies suggested that improved interactions within loops 3 and 4, and C-terminal of Tap1a-OPT and the NaV channel voltage-sensor domain II were the main drivers of potency optimization. Overall, the rationally designed peptide Tap1a-OPT displayed new and refined structure-function features which are likely the major contributors to its enhanced bioactive properties observed in vivo. This work contributes to the rapid engineering and optimization of potent spider peptides multi-targeting NaV channels, and the research into novel drugs to treat neurological diseases.

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Targeting CDK5 in Astrocytes Promotes Calcium Homeostasis Under Excitotoxic Conditions

Frontiers in Cellular Neuroscience ◽

10.3389/fncel.2021.643717 ◽

2021 ◽

Vol 15 ◽

Author(s):

Luisa Fernanda Toro-Fernández ◽

Juan Camilo Zuluaga-Monares ◽

Ana María Saldarriaga-Cartagena ◽

Gloria Patricia Cardona-Gómez ◽

Rafael Posada-Duque

Keyword(s):

Calcium Homeostasis ◽

Calcium Influx ◽

Ex Vivo ◽

Hippocampal Slices ◽

Glutamate Excitotoxicity ◽

Neural Cells ◽

Neuroprotective Effects ◽

Hippocampal Area ◽

Therapy Target

Glutamate excitotoxicity triggers overactivation of CDK5 and increases calcium influx in neural cells, which promotes dendritic retraction, spine loss, increased mitochondrial calcium from the endoplasmic reticulum, and neuronal death. Our previous studies showed that CDK5 knockdown (KD) in astrocytes improves neurovascular integrity and cognitive functions and exerts neuroprotective effects. However, how CDK5-targeted astrocytes affect calcium regulation and whether this phenomenon is associated with changes in neuronal plasticity have not yet been analyzed. In this study, CDK5 KD astrocytes transplanted in CA3 remained at the injection site without proliferation, regulated calcium in the CA1 hippocampal region after excitotoxicity by glutamate in ex vivo hippocampal slices, improving synapsin and PSD95 clustering. These CDK5 KD astrocytes induced astrocyte stellation and neuroprotection after excitotoxicity induced by glutamate in vitro. Also, these effects were supported by CDK5 inhibition (CDK5i) in vitro through intracellular stabilization of calcium levels in astrocytes. Additionally, these cells in cocultures restored calcium homeostasis in neurons, redistributing calcium from somas to dendrites, accompanied by dendrite branching, higher dendritic spines and synapsin-PSD95 clustering. In summary, induction of calcium homeostasis at the CA1 hippocampal area by CDK5 KD astrocytes transplanted in the CA3 area highlights the role of astrocytes as a cell therapy target due to CDK5-KD astrocyte-mediated synaptic clustering, calcium spreading regulation between both areas, and recovery of the intracellular astrocyte-neuron calcium imbalance and plasticity impairment generated by glutamate excitotoxicity.

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