Development of a novel in vitro assay to screen for neuroprotective drugs against iatrogenic neurite shortening

This work tries to help overcome the lack of relevant translational screening assays, as a limitation for the identification of novel analgesics for neuropathic pain. Hyperexcitability and neurite shortening are common adverse effects of antiviral and antitumor drugs, leading to neuropathic pain. Now, as seen in the drug screening that we developed here, a high-content microscopy-based assay with immortalized dorsal root ganglia (DRG) neurons (differentiated F11 cells) allowed to identify drugs able to protect against the iatrogenic neurite shortening induced by the antitumor drug vincristine and the antiviral drug rilpivirine. We observed that vincristine and rilpivirine induced a significant reduction in the neurite length, which was reverted by α-lipoic acid. We had also evidenced protective effects of pregabalin and melatonin, acting through the α2δ-2 subunit of the voltage-dependent calcium channels and the MT1 receptor, respectively. Additionally, two hits originated from a previous primary screening aimed to detect inhibitors of hyperexcitability to inflammatory mediators in DRG neurons (nitrendipine and felodipine) also prevented neurite shortening in our model. In summary, in this work we developed a novel secondary assay for identifying hits with neuroprotective effect against iatrogenic neurite shortening, consistent with the anti-hyperexcitability action previously tested: highlighting nitrendipine and felodipine against iatrogenic damage in DRG neurons.

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Isorhynchophylline Protects PC12 Cells Against Beta-Amyloid-Induced Apoptosis via PI3K/Akt Signaling Pathway

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/163057 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 19

Author(s):

Yan-Fang Xian ◽

Zhi-Xiu Lin ◽

Qing-Qiu Mao ◽

Jian-Nan Chen ◽

Zi-Ren Su ◽

...

Keyword(s):

Signaling Pathway ◽

Pc12 Cells ◽

Molecular Mechanisms ◽

Glycogen Synthase ◽

Neuroprotective Effect ◽

Protective Action ◽

Protective Effects ◽

Phosphorylated Akt ◽

Induced Apoptosis

The neurotoxicity of amyloid-β(Aβ) has been implicated as a critical cause of Alzheimer’s disease. Isorhynchophylline (IRN), an oxindole alkaloid isolated fromUncaria rhynchophylla,exerts neuroprotective effect againstAβ25–35-induced neurotoxicityin vitro. However, the exact mechanism for its neuroprotective effect is not well understood. The present study aimed to investigate the molecular mechanisms underlying the protective action of IRN againstAβ25–35-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. Pretreatment with IRN significantly increased the cell viability, inhibited the release of lactate dehydrogenase and the extent of DNA fragmentation inAβ25–35-treated cells. IRN treatment was able to enhance the protein levels of phosphorylated Akt (p-Akt) and glycogen synthase kinase-3β(p-GSK-3β). Lithium chloride blockedAβ25–35-induced cellular apoptosis in a similar manner as IRN, suggesting that GSK-3βinhibition was involved in neuroprotective action of IRN. Pretreatment with LY294002 completely abolished the protective effects of IRN. Furthermore, IRN reversedAβ25–35-induced attenuation in the level of phosphorylated cyclic AMP response element binding protein (p-CREB) and the effect of IRN could be blocked by the PI3K inhibitor. These experimental findings unambiguously suggested that the protective effect of IRN againstAβ25–35-induced apoptosis in PC12 cells was associated with the enhancement of p-CREB expression via PI3K/Akt/GSK-3βsignaling pathway.

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Neuroprotective Effect of Bergamot Juice in 6-OHDA-Induced SH-SY5Y Cell Death, an In Vitro Model of Parkinson’s Disease

Pharmaceutics ◽

10.3390/pharmaceutics12040326 ◽

2020 ◽

Vol 12 (4) ◽

pp. 326 ◽

Cited By ~ 3

Author(s):

Nadia Ferlazzo ◽

Santa Cirmi ◽

Alessandro Maugeri ◽

Caterina Russo ◽

Giovanni Enrico Lombardo ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cell Death ◽

Nuclear Translocation ◽

Neuroprotective Effect ◽

Neuroblastoma Cells ◽

Specific Cell ◽

Protective Effects ◽

Human Neuroblastoma

Much evidence suggests that both oxidative stress and apoptosis play a key role in the pathogenesis of Parkinson’s disease (PD). The present study aims to evaluate the protective effect of bergamot juice (BJ) against 6-hydroxydopamine (6-OHDA)- or H2O2-induced cell death. Treatment of differentiated SH-SY5Y human neuroblastoma cells with 6-OHDA or H2O2 resulted in cell death that was significantly reduced by the pre-treatment with BJ. The protective effects of BJ seem to correlate with the reduction of intracellular reactive oxygen species and nitric oxide generation caused by 6-OHDA or H2O2. BJ also attenuated mitochondrial dysfunction, caspase-3 activation, imbalance of pro- and anti-apoptotic proteins, MAPKs activation and reduced NF-ĸB nuclear translocation evoked by neurotoxic agents. Additionally, BJ exhibited excellent antioxidant capability in cell-free assays. Collectively, our results suggest that BJ exerts neuroprotective effect through the interplay with specific cell targets and its antioxidant activity, making it worthy of consideration for the management of neurodegenerative diseases.

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Identification of the target of gabapentinoid action in neuropathic pain

10.1093/med/9780198834359.003.0070 ◽

2018 ◽

Author(s):

Turo J. Nurmikko

Keyword(s):

Neuropathic Pain ◽

Scientific Community ◽

Oral Absorption ◽

Molecular Target ◽

Wild Type ◽

Seminal Paper ◽

Voltage Gated ◽

Voltage Dependent ◽

Voltage Dependent Calcium Channels

The landmark paper discussed in this chapter is ‘Identification of the α‎2-δ‎-1 subunit of voltage-dependent calcium channels as a molecular target for pain mediating the analgesic actions of pregabalin’, published by Field et al. in 2006. In this seminal paper, Field et al. demonstrated that the anti-allodynic effect of pregabalin is related to its binding to the α‎2δ‎-1 subunit of the voltage-gated calcium channel. In transgenic mice lacking this subunit, pregabalin had no effect on allodynia induced by sciatic nerve ligation, whereas, in wild-type mice, there was a substantial anti-allodynic response. This discovery was well received by the scientific community and was considered to conclusively establish the mechanism of action of pregabalin, which has remarkably similar properties to gabapentin but with increased potency and oral absorption. This exciting result acted as an impetus for further studies on the role of the subunit in the development and maintenance of neuropathic pain.

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Voltage-dependent calcium channels in ventricular cells of rainbow trout: effect of temperature changes in vitro

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2000.278.6.r1524 ◽

2000 ◽

Vol 278 (6) ◽

pp. R1524-R1534 ◽

Cited By ~ 3

Author(s):

Catherine S. Kim ◽

Mary D. Coyne ◽

Judith K. Gwathmey

Keyword(s):

Rainbow Trout ◽

Calcium Channels ◽

Temperature Sensitivity ◽

Calcium Currents ◽

Temperature Dependency ◽

Patch Clamp Technique ◽

Ventricular Cells ◽

Voltage Dependent ◽

Voltage Dependent Calcium Channels

Voltage-dependent calcium channels (VDCC) in ventricular myocytes from rainbow trout ( Oncorhynchus mykiss) were investigated in vitro using the perforated patch-clamp technique, which maintains the integrity of the intracellular milieu. First, we characterized the current using barium as the charge carrier and established the doses of various pharmacological agents to use these agents in additional studies. Second, we examined the current at several physiological temperatures to determine temperature dependency. The calcium currents at 10°C (acclimation temperature) were identified as l-type calcium currents based on their kinetic behavior and response to various calcium channel agonists and antagonists. Myocytes were chilled (4°C) and warmed (18 and 22°C), and the response of VDCC to varying temperatures was observed. There was no significant dependency of the current amplitude and kinetics on temperature. Amplitude decreased 25–36% at 4°C (Q10 ∼1.89) and increased 18% at 18°C (Q10 ∼1.23) in control, Bay K8644 (Bay K)-, and forskolin-enhanced currents. The inactivation rates (τi) did not demonstrate a temperature sensitivity for the VDCC (Q10 1.23–1.92); Bay K treatment, however, increased temperature sensitivity of τi between 10 and 18°C (Q10 3.98). The low Q10 values for VDCC are consistent with a minimal temperature sensitivity of trout myocytes between 4 and 22°C. This low-temperature dependency may provide an important role for sarcolemmal calcium channels in adaptation to varying environmental temperatures in trout.

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Role of calcium and calmodulin in release of kallikrein and tonin from rat submandibular gland

AJP Cell Physiology ◽

10.1152/ajpcell.1986.250.3.c480 ◽

1986 ◽

Vol 250 (3) ◽

pp. C480-C485 ◽

Cited By ~ 11

Author(s):

S. R. Maitra ◽

O. A. Carretero ◽

S. W. Smith ◽

S. F. Rabito

Keyword(s):

Submandibular Gland ◽

Incubation Medium ◽

High Concentration ◽

Calcium Blockers ◽

Control Value ◽

Voltage Dependent ◽

Voltage Dependent Calcium Channels ◽

Intracellular Mediators

We investigated the role of calcium and calmodulin as intracellular mediators of kallikrein and tonin release induced by norepinephrine (NE). We studied the secretion rate of kallikrein and tonin from submandibular gland of rat in response to NE in the presence or absence of calcium, two calcium blockers, and four different calmodulin antagonists. Submandibular gland slices were incubated in vitro, and glandular kallikrein and tonin secreted into the incubation medium were determined by direct radioimmunoassays and expressed as nanograms per minute per milligram tissue. NE (10(-5) and 10(-4) M) increased the kallikrein secretion from the control value of 8.2 +/- 2.6 to 134.9 +/- 41.4 (P less than 0.05) and to 191.2 +/- 62.7 (P less than 0.05), and the release of tonin from a basal rate of 3.5 +/- 0.6 to 51.5 +/- 9.1 (P less than 0.05) and to 64.4 +/- 13.7 (P less than 0.05). The deletion of calcium and addition of EGTA into the incubation medium significantly attenuated the secretion of kallikrein and tonin induced by NE. Nifedipine, at concentrations which inhibit voltage-dependent calcium channels, did not affect the release of kallikrein and tonin, and only a high concentration (10(-4) M) reduced the release. TMB-8, a blocker of intracellular calcium, had no effect either. Phenothiazines, triflupromazine (10(-6) M) and trifluoperazine (10(-4) M), decreased significantly the kallikrein release elicited by 10(-5) M NE.(ABSTRACT TRUNCATED AT 250 WORDS)

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DHEA Attenuates Microglial Activation via Induction of JMJD3 in Experimental Subarachnoid Haemorrhage

Journal of Neuroinflammation ◽

10.1186/s12974-019-1641-y ◽

2019 ◽

Vol 16 (1) ◽

Cited By ~ 7

Author(s):

Tao Tao ◽

Guang-Jie Liu ◽

Xuan Shi ◽

Yan Zhou ◽

Yue Lu ◽

...

Keyword(s):

Subarachnoid Haemorrhage ◽

Microglial Activation ◽

Neuronal Damage ◽

Neuroprotective Effect ◽

Early Brain Injury ◽

Protective Effects ◽

In Vivo Models ◽

The Brain

Abstract Background Microglia are resident immune cells in the central nervous system and central to the innate immune system. Excessive activation of microglia after subarachnoid haemorrhage (SAH) contributes greatly to early brain injury, which is responsible for poor outcomes. Dehydroepiandrosterone (DHEA), a steroid hormone enriched in the brain, has recently been found to regulate microglial activation. The purpose of this study was to address the role of DHEA in SAH. Methods We used in vivo models of endovascular perforation and in vitro models of haemoglobin exposure to illustrate the effects of DHEA on microglia in SAH. Results In experimental SAH mice, exogenous DHEA administration increased DHEA levels in the brain and modulated microglial activation. Ameliorated neuronal damage and improved neurological outcomes were also observed in the SAH mice pretreated with DHEA, suggesting neuronal protective effects of DHEA. In cultured microglia, DHEA elevated the mRNA and protein levels of Jumonji d3 (JMJD3, histone 3 demethylase) after haemoglobin exposure, downregulated the H3K27me3 level, and inhibited the transcription of proinflammatory genes. The devastating proinflammatory microglia-mediated effects on primary neurons were also attenuated by DHEA; however, specific inhibition of JMJD3 abolished the protective effects of DHEA. We next verified that DHEA-induced JMJD3 expression, at least in part, through the tropomyosin-related kinase A (TrkA)/Akt signalling pathway. Conclusions DHEA has a neuroprotective effect after SAH. Moreover, DHEA increases microglial JMJD3 expression to regulate proinflammatory/anti-inflammatory microglial activation after haemoglobin exposure, thereby suppressing inflammation.

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Neuropathic pain: Role of voltage-dependent calcium channels

Regional Anesthesia and Pain Medicine ◽

10.1016/s1098-7339(00)90012-9 ◽

2000 ◽

Vol 25 (3) ◽

pp. 283-285 ◽

Cited By ~ 2

Author(s):

S CHAPLAN

Keyword(s):

Neuropathic Pain ◽

Calcium Channels ◽

Voltage Dependent ◽

Voltage Dependent Calcium Channels

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Neuropharmacological Effects of Quercetin: A Literature-Based Review

Frontiers in Pharmacology ◽

10.3389/fphar.2021.665031 ◽

2021 ◽

Vol 12 ◽

Author(s):

Md. Shahazul Islam ◽

Cristina Quispe ◽

Rajib Hossain ◽

Muhammad Torequl Islam ◽

Ahmed Al-Harrasi ◽

...

Keyword(s):

Neurodegenerative Diseases ◽

Neuroprotective Effect ◽

Animal Experiments ◽

Amyloid Β ◽

Neuronal Injury ◽

Amyloid Β Peptide ◽

Protective Effects ◽

Neuroprotective Effects

Quercetin (QUR) is a natural bioactive flavonoid that has been lately very studied for its beneficial properties in many pathologies. Its neuroprotective effects have been demonstrated in many in vitro studies, as well as in vivo animal experiments and human trials. QUR protects the organism against neurotoxic chemicals and also can prevent the evolution and development of neuronal injury and neurodegeneration. The present work aimed to summarize the literature about the neuroprotective effect of QUR using known database sources. Besides, this review focuses on the assessment of the potential utilization of QUR as a complementary or alternative medicine for preventing and treating neurodegenerative diseases. An up-to-date search was conducted in PubMed, Science Direct and Google Scholar for published work dealing with the neuroprotective effects of QUR against neurotoxic chemicals or in neuronal injury, and in the treatment of neurodegenerative diseases. Findings suggest that QUR possess neuropharmacological protective effects in neurodegenerative brain disorders such as Alzheimer’s disease, Amyloid β peptide, Parkinson’s disease, Huntington's disease, multiple sclerosis, and amyotrophic lateral sclerosis. In summary, this review emphasizes the neuroprotective effects of QUR and its advantages in being used in complementary medicine for the prevention and treatment o of different neurodegenerative diseases.

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The contractile action of platelet-activating factor on gallbladder smooth muscle

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2000.279.1.g67 ◽

2000 ◽

Vol 279 (1) ◽

pp. G67-G72 ◽

Cited By ~ 5

Author(s):

Henry P. Parkman ◽

Arlene N. James ◽

James P. Ryan

Keyword(s):

Pertussis Toxin ◽

Contractile Response ◽

Calcium Influx ◽

Platelet Activating Factor ◽

Extracellular Calcium ◽

Motor Dysfunction ◽

Gallbladder Contraction ◽

Voltage Dependent ◽

Voltage Dependent Calcium Channels

Platelet-activating factor (PAF) may be a mediator of some sequelae of cholecystitis, a disorder with gallbladder motor dysfunction. The aims of this study were to determine the effect and mechanism of PAF on gallbladder muscle. Exogenous administration of PAF-16 or PAF-18 caused dose-dependent contractions of gallbladder muscle strips in vitro with threshold doses of 1 ng/ml and 10 ng/ml, respectively. The PAF-induced contractions were not significantly reduced by TTX, atropine, or hexamethonium but were significantly inhibited with the PAF receptor antagonists ginkolide B and CV-3988. The PAF-induced contraction was reduced by indomethacin. Preventing influx of extracellular calcium with a calcium-free solution nearly abolished the PAF contractile response. Nifedipine inhibited the PAF contractile response, whereas ryanodine had no effect. Pertussis toxin reduced the PAF contractile response. In conclusion, PAF causes gallbladder contraction through specific PAF receptors on gallbladder muscle. These PAF receptors appear to be linked to a prostaglandin-mediated mechanism and to pertussis toxin-sensitive G proteins. The contractile response is largely mediated through the utilization of extracellular calcium influx through voltage-dependent calcium channels.

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