Authors: PinFen Chua, William K Lim

Stroke causes death and disability globally but no neuroprotectant is approved for post-stroke neuronal injury. Neuroprotective compounds can be identified using oxygen glucose deprivation (OGD) of neuronal cells as an in vitro stroke model. Nerve growth factor (NGF)-differentiated PC12 pheochromocytoma cells are frequently used. However, investigators often find their clonal variant undifferentiable and are uncertain of optimal culture conditions. Hence we studied 3 commonly used PC12 variants: PC12 Adh, PC12 from Riken Cell Bank (PC12 Riken) and Neuroscreen-1 (NS-1) cells. We found DMEM the optimal media for PC12 Riken and NS-1 cells. Using a novel serum-free media approach, we identified collagen IV as the preferred adhesive substrate for both cell lines. We found PC12 Adh cells cannot attach without serum and is unable to differentiate using NGF. NS-1 cells differentiated to a maximal 72.7 ± 5.2% %, with substantial basal differentiation. We optimised differentiated NS-1 cells for an in vitro stroke model using 3 h of OGD resulting in ~ 70% viable cells. We screened 5 reported neuroprotectants and provide the first report that serotonin is antiapoptotic in a stroke model and the 5-HT agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) is neuroprotective in PC12 cells. Thus we demonstrate the optimisation and validation for a PC12 cell-based in vitro stroke model.

Topics: 8-Hydroxy-2-(di-n-propylamino)tetralin; Animals; Apoptosis; Cell Differentiation; Cell Hypoxia; Cell Survival; Culture Media, Serum-Free; Models, Biological; Neuroprotective Agents; PC12 Cells; Rats; Serotonin; Serotonin 5-HT1 Receptor Agonists; Stroke

PubMed: 33854099
DOI: 10.1038/s41598-021-87431-4

Authors: Mark P Maskery, Christian Holscher, Stephanie P Jones...

Stroke mortality and morbidity is expected to rise. Despite considerable recent advances within acute ischemic stroke treatment, scope remains for development of widely applicable neuroprotective agents. Glucagon-like peptide-1 receptor agonists (GLP-1RAs), originally licensed for the management of Type 2 Diabetes Mellitus, have demonstrated pre-clinical neuroprotective efficacy in a range of neurodegenerative conditions. This systematic scoping review reports the pre-clinical basis of GLP-1RAs as neuroprotective agents in acute ischemic stroke and their translation into clinical trials. We included 35 pre-clinical studies, 11 retrospective database studies, 7 cardiovascular outcome trials and 4 prospective clinical studies. Pre-clinical neuroprotection was demonstrated in normoglycemic models when administration was delayed by up to 24 h following stroke induction. Outcomes included reduced infarct volume, apoptosis, oxidative stress and inflammation alongside increased neurogenesis, angiogenesis and cerebral blood flow. Improved neurological function and a trend towards increased survival were also reported. Cardiovascular outcomes trials reported a significant reduction in stroke incidence with semaglutide and dulaglutide. Retrospective database studies show a trend towards neuroprotection. Prospective interventional clinical trials are on-going, but initial indicators of safety and tolerability are favourable. Ultimately, we propose that repurposing GLP-1RAs is potentially advantageous but appropriately designed trials are needed to determine clinical efficacy and cost-effectiveness.

Topics: Animals; Disease Models, Animal; Glucagon-Like Peptide-1 Receptor; Humans; Ischemic Stroke; Neuroprotective Agents; Prospective Studies; Retrospective Studies

PubMed: 32954901
DOI: 10.1177/0271678X20952011

Authors: Xiaohui Jia, Menglu Jia, Yuqin Yang...

Baicalein, a famously effective component of the traditional Chinese medicine Rhizoma Huang Qin ( L.), has been proved to have potent neuroprotection and anti-platelet aggregation effects with few side effects. Meanwhile, recent studies have revealed that the introduction of amino acid to baicalein could improve its neuroprotective activity. In the present study, a series of novel baicalein amino acid derivatives were designed, synthesized, and screened for their neuroprotective effect against -butyl, hydroperoxide-induced, SH-SY5Y neurotoxicity cells and toxicity on the normal H9C2 cell line by standard methylthiazol tetrazolium (MTT) assay. In addition, all of the newly synthesized compounds were characterized by H-NMR, C-NMR, and high resolution mass spectrometry (HR-MS). The results showed that most of the compounds provided more potent neuroprotection than baicalein, and were equivalent to the positive drug edaravin. They showed no obvious cytotoxicity on normal H9C2 cells. Notably, the most active compound displayed the highest protective effect (50% effective concentration (EC) = 4.31 μM) against -butyl, hydroperoxide-induced, SH-SY5Y neurotoxicity cells, which was much better than the baicalein (EC = 24.77 μM) and edaravin (EC = 5.62 μM). Further research on the chick chorioallantoic membrane (CAM) model indicated that compound could significantly increase angiogenesis, which might promote neurovascular proliferation. The detection of apoptosis analysis showed that compound could dramatically alleviate morphological manifestations of cell damage. Moreover, the benzyloxycarbonyl (cbz)-protected baicalein amino acid derivatives showed better neuroprotective activity than the -Butyloxy carbonyl (boc)-protected derivatives.

Topics: Amino Acids; Angiogenesis Inducing Agents; Animals; Apoptosis; Cell Line, Tumor; Cell Survival; Chemistry Techniques, Synthetic; Chick Embryo; Dose-Response Relationship, Drug; Flavanones; Humans; Inhibitory Concentration 50; Molecular Structure; Neuroprotective Agents; Structure-Activity Relationship

PubMed: 31601055
DOI: 10.3390/molecules24203647

Authors: Yi-Fan Chen, Chien-Huang Wu, Li-Hsien Chen...

Chemotherapy-induced neurotoxicity is a common adverse effect of cancer treatment. No medication has been shown to be effective in the prevention or treatment of chemotherapy-induced neurotoxicity. Using minoxidil as an initial template for structural modifications in conjunction with an in vitro neurite outgrowth assay, an image-based high-content screening platform, and mouse behavior models, an effective neuroprotective agent CN016 was discovered. Our results showed that CN016 could inhibit paclitaxel-induced inflammatory responses and infiltration of immune cells into sensory neurons significantly. Thus, the suppression of proinflammatory factors elucidates, in part, the mechanism of action of CN016 on alleviating paclitaxel-induced peripheral neuropathy. Based on excellent efficacy in improving behavioral functions, high safety profiles (MTD > 500 mg/kg), and a large therapeutic window (MTD/MED > 50) in mice, CN016 might have great potential to become a peripherally neuroprotective agent to prevent neurotoxicity caused by chemotherapeutics as typified by paclitaxel.

Topics: Animals; Antineoplastic Agents; Antineoplastic Agents, Phytogenic; Ganglia, Spinal; Mice; Neuroprotective Agents; Paclitaxel; Peripheral Nervous System Diseases

PubMed: 35234475
DOI: 10.1021/acs.jmedchem.1c01912

Authors: Geisa Gabriela da Silva, Lúcia Pinheiro Santos Pimenta, Júlio Onésio Ferreira Melo...

Avocado () is a widely consumed fruit and a rich source of nutrients and phytochemicals. Its industrial processing generates peels and seeds which represent 30% of the fruit. Environmental issues related to these wastes are rapidly increasing and likely to double, according to expected avocado production. Therefore, this work aimed to evaluate the potential of hexane and ethanolic peel (PEL-H, PEL-ET) and seed (SED-H, SED-ET) extracts from avocado as sources of neuroprotective compounds. Minerals, total phenol (TPC), total flavonoid (TF), and lipid contents were determined by absorption spectroscopy and gas chromatography. In addition, phytochemicals were putatively identified by paper spray mass spectrometry (PSMS). The extracts were good sources of Ca, Mg, Fe, Zn, ω-6 linoleic acid, and flavonoids. Moreover, fifty-five metabolites were detected in the extracts, consisting mainly of phenolic acids, flavonoids, and alkaloids. The in vitro antioxidant capacity (FRAP and DPPH), acetylcholinesterase inhibition, and in vivo neuroprotective capacity were evaluated. PEL-ET was the best acetylcholinesterase inhibitor, with no significant difference ( > 0.05) compared to the control eserine, and it showed neither preventive nor regenerative effect in the neuroprotection assay. SED-ET demonstrated a significant protective effect compared to the control, suggesting neuroprotection against rotenone-induced neurological damage.

Topics: Acetylcholinesterase; Antioxidants; Cholinesterase Inhibitors; Gas Chromatography-Mass Spectrometry; Neuroprotective Agents; Persea; Phytochemicals; Plant Extracts

PubMed: 35335256
DOI: 10.3390/molecules27061892

A Novel Synthetic Precursor of Styryl Sulfone Neuroprotective Agents Inhibits Neuroinflammatory Responses and Oxidative Stress Damage through the P38 Signaling Pathway in the Cell and Animal Model of Parkinson's Disease.

Authors: Ying Guo, Zhizhong Ma, Xianling Ning...

A novel class of styryl sulfones were designed and synthesized as CAPE derivatives by our work team, which showed a multi-target neuroprotective effect, including antioxidative and anti-neuroinflammatory properties. However, the underlying mechanisms remain unclear. In the present study, the anti-Parkinson's disease (PD) activity of 10 novel styryl sulfone compounds was screened by the cell viability test and the NO inhibition test in vitro. It was found that exhibited the highest activity against PD among them. In a MPTP-induced mouse model of PD, the biological activity of was validated through suppressing dopamine neurotoxicity, microglial activation, and astrocytes activation. With compound , we conducted the mechanistic studies about anti-inflammatory responses through inhibition of p38 phosphorylation to protect dopaminergic neurons, and antioxidant effects through promoting nuclear factor erythroid 2-related factor 2 (Nrf2). The results revealed that could significantly inhibit 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/1-methyl-4-phenylpyridinium (MPTP/MPP)-induced p38 mitogen-activated protein kinase (MAPK) activation in both in vitro and in vivo PD models, thus inhibiting the NF-κB-mediated neuroinflammation-related apoptosis pathway. Simultaneously, it could promote Nrf2 nuclear transfer, and upregulate the expression of antioxidant phase II detoxification enzymes HO-1 and GCLC, and then reduce oxidative damage.

Topics: Animals; Cells, Cultured; Disease Models, Animal; Inflammation; Neuroprotective Agents; Oxidative Stress; Parkinson Disease; Rats; Rats, Sprague-Dawley; Signal Transduction; Styrenes; Sulfones; p38 Mitogen-Activated Protein Kinases

PubMed: 34500807
DOI: 10.3390/molecules26175371

Authors: Tom Wiesen, Daphne Atlas

Parkinson's disease (PD) is characterized by a gradual degeneration of the dopaminergic neurons in the substantia nigra pars compacta (SNpC). Levodopa, the standard PD treatment, provides the missing dopamine in SNpC, but ultimately after a honeymoon with levodopa treatment the neurodegenerative process and the progression of the disease continue. Aimed at prolonging the life of dopaminergic cells, we prepared the levodopa precursors SuperDopa (SD) and SueprDopamide (SDA), in which levodopa is merged with the antioxidant N-acetylcysteine (NAC) into a single molecule. Rotenone is a mitochondrial complex inhibitor often used as experimental model of PD. In vivo, SD and SDA treatment show a significant relief of motor disabilities in rotenone-injected rats. SD and SDA also lower rotenone-induced-α-synuclein (α-syn) expression in human SH-SY5Y cells, and α-syn oligomerization in α-syn-overexpressing-HEK293 cells. In the neuronal SH-SY5Y cells, SD and SDA reverse oxidative stress-induced phosphorylation of cJun-N-terminal kinase (JNK) and p38-mitogen-activated kinase (p38). Attenuation of the MAPK-inflammatory/apoptotic pathway in SH-SY5Y cells concurrent with protection of rotenone-triggered motor impairment in rats, is a manifestation of the combined antioxidant/anti-inflammatory activity of SD and SDA together with levodopa release. The concept of joined therapies into a single molecule, where levodopa precursors confer antioxidant activity by enabling NAC delivery across the BBB, provides a potential disease-modifying treatment for slowing PD progression.

Topics: Animals; Antioxidants; Dopaminergic Neurons; HEK293 Cells; Humans; Levodopa; Neuroprotective Agents; Parkinson Disease; Rats; Rotenone

PubMed: 35277478
DOI: 10.1038/s41419-022-04667-2

Review

Authors: Khalil Mallah, Christine Couch, Davis M Borucki...

Neurological disorders are major contributors to death and disability worldwide. The pathology of injuries and disease processes includes a cascade of events that often involve molecular and cellular components of the immune system and their interaction with cells and structures within the central nervous system. Because of this, there has been great interest in developing neuroprotective therapeutic approaches that target neuroinflammatory pathways. Several neuroprotective anti-inflammatory agents have been investigated in clinical trials for a variety of neurological diseases and injuries, but to date the results from the great majority of these trials has been disappointing. There nevertheless remains great interest in the development of neuroprotective strategies in this arena. With this in mind, the complement system is being increasingly discussed as an attractive therapeutic target for treating brain injury and neurodegenerative conditions, due to emerging data supporting a pivotal role for complement in promoting multiple downstream activities that promote neuroinflammation and degeneration. As we move forward in testing additional neuroprotective and immune-modulating agents, we believe it will be useful to review past trials and discuss potential factors that may have contributed to failure, which will assist with future agent selection and trial design, including for complement inhibitors. In this context, we also discuss inhibition of the complement system as a potential neuroprotective strategy for neuropathologies of the central nervous system.

Topics: Animals; Anti-Inflammatory Agents; Brain Injuries, Traumatic; Central Nervous System; Central Nervous System Diseases; Clinical Trials as Topic; Humans; Neuroprotective Agents

PubMed: 33013859
DOI: 10.3389/fimmu.2020.02021

Authors: Catarina Oliveira, Donatella Bagetta, Fernando Cagide...

The discovery of new chemical entities endowed with potent and selective acetylcholinesterase (AChE) and/or butyrylcholinesterase (BChE) inhibitory activity is still a relevant subject for Alzheimer's disease therapy. Therefore, a small library of benzoic based amide nitrones (compounds 24 to 42) was synthesized and screened toward cholinesterase enzymes. SAR studies showed that the tert-butyl moiety is the most favourable nitrone pattern. In general, tert-butyl derivatives effectively inhibited AChE, being compound 33 the most potent (IC = 8.3 ± 0.3 μM; Ki 5.2 μM). The data pointed to a non-competitive inhibition mechanism of action, which was also observed for the standard donepezil. None of compounds showed BChE inhibitory activity. Molecular modelling studies provided insights into the enzyme-inhibitor interactions and rationalised the experimental data, confirming that the binding mode of nitrones 33 and 38 towards AChE has the most favourable binding free energy. The tert-butylnitrones 33 and 38 were not cytotoxic on different cell lines (SH-SY5Y and HepG2). Moreover, compound 33 was able to prevent t-BHP-induced oxidative stress in SH-SY5Y differentiated cells. Due to its AChE selectivity and promising cytoprotective properties, as well as its appropriate drug-like profile pointing toward blood-brain barrier permeability, compound 33 is proposed as a valid lead for a further optimization step.

Topics: Acetylcholinesterase; Benzamides; Cell Line, Tumor; Cell Survival; Cholinesterase Inhibitors; Humans; Imines; Kinetics; Molecular Docking Simulation; Molecular Structure; Neuroprotective Agents; Small Molecule Libraries; Structure-Activity Relationship

PubMed: 31029943
DOI: 10.1016/j.ejmech.2019.04.026

Authors: Ammar Jastaniah, Irina N Gaisina, Rachel C Knopp...

Calpain inhibitors have been proposed as drug candidates for neurodegenerative disorders, with ABT-957 entering clinical trials for Alzheimer's disease and mild cognitive impairment. The structure of ABT-957 was very recently disclosed, and trials were terminated owing to inadequate CNS concentrations to obtain a pharmacodynamic effect. The multistep synthesis of an α-ketoamide peptidomimetic inhibitor series potentially including ABT-957 was optimized to yield diastereomerically pure compounds that are potent and selective for calpain-1 over papain and cathepsins B and K. As the final oxidation step, with its optimized synthesis protocol, does not alter the configuration of the substrate, the synthesis of the diastereomeric pair (R)-1-benzyl-N-((S)-4-((4-fluorobenzyl)amino)-3,4-dioxo-1-phenylbutan-2-yl)-5-oxopyrrolidine-2-carboxamide (1 c) and (R)-1-benzyl-N-((R)-4-((4-fluorobenzyl)amino)-3,4-dioxo-1-phenylbutan-2-yl)-5-oxopyrrolidine-2-carboxamide (1 g) was feasible. This allowed the exploration of stereoselective inhibition of calpain-1, with 1 c (IC =78 nM) being significantly more potent than 1 g. Moreover, inhibitor 1 c restored cognitive function in amnestic mice.

Topics: Amnesia; Animals; Calpain; Glycoproteins; Mice; Molecular Structure; Neuroprotective Agents; Pyrrolidines; Scopolamine; Stereoisomerism

PubMed: 32840034
DOI: 10.1002/cmdc.202000385