A pain killer without analgesic tolerance designed by co-targeting PSD-95-nNOS interaction and α2-containning GABAARs

Tat-NR2B9c attenuates oxidative stress via inhibition of PSD95-NR2B-nNOS complex after subarachnoid hemorrhage in rats

Oxidative stress plays important roles in the pathogenesis of early brain injury (EBI) after subarachnoid hemorrhage (SAH). Tat-NR2B9c has shown efficacy as a neuroprotective agent in several studies. Here, we identified the neuroprotective role of Tat-NR2B9c after SAH and its related mechanisms. The results showed that Tat-NR2B9c treatment attenuated oxidative stress, therefore alleviated neuronal apoptosis and neurological deficits after SAH. Tat-NR2B9c treatment could alleviate mitochondrial vacuolization induced by SAH. Compared to SAH + vehicle group, Tat-NR2B9c resulted in the decrease of Acetylated superoxide dismutase2 (Ac-SOD2), Bcl-2-associated X protein (Bax) and cleaved-caspase3 (CC3) protein expression, and the up-regulation of Sirtunin 3 (Sirt3) and Bcl-2 protein level. Moreover, Tat-NR2B9c attenuated excitotoxicity by inhibiting the interaction of PSD95-NR2B-nNOS. Our results demonstrated that Tat-NR2B9c inhibited oxidative stress via inhibition of PSD95-NR2B-nNOS complex formation after SAH. Tat-NR2B9c may serve as a potential treatment for SAH induced brain injury.

SIRT3 facilitates mitochondrial structural repair and functional recovery in rats after ischemic stroke by promoting OPA1 expression and activity

BACKGROUND

Optical atrophy 1 (OPA1), a protein accountable for mitochondrial fusion, facilitates the restoration of mitochondrial structure and function following cerebral ischemia/reperfusion (I/R) injury. The OPA1-conferred mitochondrial protection involves its expression and activity, which can be improved by SIRT3 in non-cerebral ischemia. Nevertheless, it remains obscure whether SIRT3 enhances the expression and activity of OPA1 after cerebral I/R injury.

METHODS

Mature male Sprague Dawley rats were intracranially injected with adeno-associated viral-Sirtuin-3(AAV-SIRT3) and AAV-sh_OPA1, followed by a 90-min temporary blockage of the middle cerebral artery and subsequent restoration of blood flow. Cultured cortical neurons of rats were transfected with LV-SIRT3 or LV-sh_OPA1 before a 2-h oxygen-glucose deprivation and reoxygenation. The rats and neurons were subsequently treated with a selective OPA1 activity inhibitor (MYLS22). The interaction between SIRT3 and OPA1 was assessed by molecular dynamics simulation technology and co-immunoprecipitation. The expression, function, and specific protective mechanism of SIRT3 were examined by various analyses.

RESULTS

SIRT3 interacted with OPA1 in the rat cerebral cortex before and after cerebral I/R. After cerebral I/R damage, SIRT3 upregulation increased the OPA1 expression, which enhanced deacetylation and OPA1 activity, thus alleviating cerebral infarct volume, neuronal apoptosis, oxidative pressure, and impairment in mitochondrial energy production; SIRT3 upregulation also improved neuromotor performance, repaired mitochondrial ultrastructure and membrane composition, and promoted the mitochondrial biogenesis. These neuroprotective effects were partly reversed by OPA1 expression interference and OPA1 activity inhibitor MYLS22.

CONCLUSION

In rats, SIRT3 enhances the expression and activity of OPA1, facilitating the repair of mitochondrial structure and functional recovery following cerebral I/R injury. These findings highlight that regulating SIRT3 may be a promising therapeutic strategy for ischemic stroke.

Rationale and design of Treatment of Acute Ischaemic Stroke with Edaravone Dexborneol II (TASTE-2): a multicentre randomised controlled trial

BACKGROUND

Edaravone dexborneol is believed to be a novel cytoprotective drug, demonstrating a synergistic combination of antioxidative and anti-inflammatory properties in animal models. The Treatment of Acute Ischaemic Stroke with Edaravone Dexborneol (TASTE) trial demonstrated its superior efficacy over edaravone alone for acute ischaemic stroke (AIS) patients. However, its efficacy in individuals undergoing endovascular therapy (EVT) remains uncertain.

AIM

To clarify the rationale and design of the TASTE II (TASTE-2) trial.

DESIGN

The TASTE-2 is a multicentre, double-blind, randomised, placebo-controlled trial designed to evaluate the efficacy and safety of edaravone dexborneol in patients with AIS and large-vessel occlusion in the anterior circulation. The eligible participants, presenting with a National Institute of Health Stroke Scale score between 6 and 25 (range 0-42, with larger values suggesting severe neurological dysfunction) and an Alberta Stroke Program Early Computed Tomography Score ranging from 6 to 10 (range 0-10, with smaller values suggesting larger infarction) within the initial 24 hours after symptom onset, will be randomly allocated to either the edaravone dexborneol group or the placebo group in equal proportions prior to thrombectomy. The treatment will be continuously administered for a duration of 10-14 days. A follow-up period of 90 days will be implemented for all participants.

STUDY OUTCOMES

The primary efficacy outcome is defined as achieving favourable functional independence, measured by a modified Rankin Scale of 0-2 at 90 days. The primary safety outcome focuses on the incidence of serious adverse events.

DISCUSSION

The TASTE-2 trial will provide evidence to determine whether the administration of edaravone dexborneol in AIS patients undergoing EVT could yield significant improvements in neurological function.

Heat Shock Protein 22 Attenuates Nerve Injury-induced Neuropathic Pain Via Improving Mitochondrial Biogenesis and Reducing Oxidative Stress Mediated By Spinal AMPK/PGC-1α Pathway in Male Rats

Heat shock protein 22 (hsp22) plays a significant role in mitochondrial biogenesis and redox balance. Moreover, it's well accepted that the impairment of mitochondrial biogenesis and redox imbalance contributes to the progress of neuropathic pain. However, there is no available evidence indicating that hsp22 can ameliorate mechanical allodynia and thermal hyperalgesia, sustain mitochondrial biogenesis and redox balance in rats with neuropathic pain. In this study, pain behavioral test, western blotting, immunofluorescence staining, quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and Dihydroethidium staining are applied to confirm the role of hsp22 in a male rat model of spared nerve injury (SNI). Our results indicate that hsp22 was significantly decreased in spinal neurons post SNI. Moreover, it was found that intrathecal injection (i.t.) with recombinant heat shock protein 22 protein (rhsp22) ameliorated mechanical allodynia and thermal hyperalgesia, facilitated nuclear respiratory factor 1 (NRF1)/ mitochondrial transcription factor A (TFAM)-dependent mitochondrial biogenesis, decreased the level of reactive oxygen species (ROS), and suppressed oxidative stress via activation of spinal adenosine 5'monophosphate-activated protein kinase (AMPK)/ peroxisome proliferative activated receptor γ coactivator 1α (PGC-1α) pathway in male rats with SNI. Furthermore, it was also demonstrated that AMPK antagonist (compound C, CC) or PGC-1α siRNA reversed the improved mechanical allodynia and thermal hyperalgesia, mitochondrial biogenesis, oxidative stress, and the decreased ROS induced by rhsp22 in male rats with SNI. These results revealed that hsp22 alleviated mechanical allodynia and thermal hyperalgesia, improved the impairment of NRF1/TFAM-dependent mitochondrial biogenesis, down-regulated the level of ROS, and mitigated oxidative stress through stimulating the spinal AMPK/PGC-1α pathway in male rats with SNI.

Preclinical evaluation of ZL006-05, a new antistroke drug with fast-onset antidepressant and anxiolytic effects

BACKGROUND

Poststroke depression and anxiety, independent predictor of poor functional outcomes, are common in the acute phase of stroke. Up to now, there is no fast-onset antidepressive and anxiolytic agents suitable for the management of acute stroke. ZL006-05, a dual-target analgesic we developed, dissociates nitric oxide synthase from postsynaptic density-95 while potentiates α2-containing γ-aminobutyric acid type A receptor. This study aims to determine whether ZL006-05 can be used as an antistroke agent with fast-onset antidepressant and anxiolytic effects.

METHODS

Photothrombotic stroke and transient middle cerebral artery occlusion were induced in rats and mice. Infarct size was measured by TTC(2,3,5-Triphenyltetrazolium chloride) staining or Nissl staining. Neurological defects were assessed by four-point scale neurological score or modified Neurological Severity Scores. Grid-walking, cylinder and modified adhesive removal tasks were conducted to assess sensorimotor functions. Spatial learning was assessed using Morris water maze task. Depression and anxiety were induced by unpredictable chronic mild stress. Depressive behaviours were assessed by tail suspension, forced swim and sucrose preference tests. Anxiety behaviours were assessed by novelty-suppressed feeding and elevated plus maze tests. Pharmacokinetics, toxicokinetics and long-term toxicity studies were performed in rats.

RESULTS

Administration of ZL006-05 in the acute phase of stroke attenuated transient and permanent ischaemic injury and ameliorated long-term functional impairments significantly, with a treatment window of 12 hours after ischemia, and reduced plasminogen activato-induced haemorrhagic transformation. ZL006-05 produced fast-onset antidepressant and anxiolytic effects with onset latency of 1 hour in the normal and CMS mice, had antidepressant and anxiolytic effects in stroke mice. ZL006-05 crossed the blood-brain barrier and distributed into the brain rapidly, and had a high safety profile in toxicokinetics and long-term toxicological studies.

CONCLUSION

ZL006-05 is a new neuroprotectant with fast-onset antidepressant and anxiolytic effects and has translational properties in terms of efficacy, safety and targeting of clinical issues.

Reperfusion and cytoprotective agents are a mutually beneficial pair in ischaemic stroke therapy: an overview of pathophysiology, pharmacological targets and candidate drugs focusing on excitotoxicity and free radical

Stroke is the second-leading cause of death and the leading cause of disability in much of the world. In particular, China faces the greatest challenge from stroke, since the population is aged quickly. In decades of clinical trials, no neuroprotectant has had reproducible efficacy on primary clinical end points, because reperfusion is probably a necessity for neuroprotection to be clinically beneficial. Fortunately, the success of thrombolysis and endovascular thrombectomy has taken us into a reperfusion era of acute ischaemic stroke (AIS) therapy. Brain cytoprotective agents can prevent detrimental effects of ischaemia, and therefore 'freeze' ischaemic penumbra before reperfusion, extend the time window for reperfusion therapy. Because reperfusion often leads to reperfusion injury, including haemorrhagic transformation, brain oedema, infarct progression and neurological worsening, cytoprotective agents will enhance the efficacy and safety of reperfusion therapy by preventing or reducing reperfusion injuries. Therefore, reperfusion and cytoprotective agents are a mutually beneficial pair in AIS therapy. In this review, we outline critical pathophysiological events causing cell death within the penumbra after ischaemia or ischaemia/reperfusion in the acute phase of AIS, focusing on excitotoxicity and free radicals. We discuss key pharmacological targets for cytoprotective therapy and evaluate the recent advances of cytoprotective agents going through clinical trials, highlighting multitarget cytoprotective agents that intervene at multiple levels of the ischaemic and reperfusion cascade.

nNOS and Neurological, Neuropsychiatric Disorders: A 20-Year Story

In the central nervous system, nitric oxide (NO), a free gas with multitudinous bioactivities, is mainly produced from the oxidation of L-arginine by neuronal nitric oxide synthase (nNOS). In the past 20 years, the studies in our group and other laboratories have suggested a significant involvement of nNOS in a variety of neurological and neuropsychiatric disorders. In particular, the interactions between the PDZ domain of nNOS and its adaptor proteins, including post-synaptic density 95, the carboxy-terminal PDZ ligand of nNOS, and the serotonin transporter, significantly influence the subcellular localization and functions of nNOS in the brain. The nNOS-mediated protein-protein interactions provide new attractive targets and guide the discovery of therapeutic drugs for neurological and neuropsychiatric disorders. Here, we summarize the work on the roles of nNOS and its association with multiple adaptor proteins on neurological and neuropsychiatric disorders.

Glutamate-releasing BEST1 channel is a new target for neuroprotection against ischemic stroke with wide time window

Many efforts have been made to understand excitotoxicity and develop neuroprotectants for the therapy of ischemic stroke. The narrow treatment time window is still to be solved. Given that the ischemic core expanded over days, treatment with an extended time window is anticipated. Bestrophin 1 (BEST1) belongs to a bestrophin family of calcium-activated chloride channels. We revealed an increase in neuronal BEST1 expression and function within the peri-infarct from 8 to 48 h after ischemic stroke in mice. Interfering the protein expression or inhibiting the channel function of BEST1 by genetic manipulation displayed neuroprotective effects and improved motor functional deficits. Using electrophysiological recordings, we demonstrated that extrasynaptic glutamate release through BEST1 channel resulted in delayed excitotoxicity. Finally, we confirmed the therapeutic efficacy of pharmacological inhibition of BEST1 during 6-72 h post-ischemia in rodents. This delayed treatment prevented the expansion of infarct volume and the exacerbation of neurological functions. Our study identifies the glutamate-releasing BEST1 channel as a potential therapeutic target against ischemic stroke with a wide time window.

Enhanced AMPAR-dependent synaptic transmission by S-nitrosylation in the vmPFC contributes to chronic inflammatory pain-induced persistent anxiety in mice

Chronic pain patients often have anxiety disorders, and some of them suffer from anxiety even after analgesic administration. In this study, we investigated the role of AMPAR-mediated synaptic transmission in the ventromedial prefrontal cortex (vmPFC) in chronic pain-induced persistent anxiety in mice and explored potential drug targets. Chronic inflammatory pain was induced in mice by bilateral injection of complete Freund's adjuvant (CFA) into the planta of the hind paws; anxiety-like behaviours were assessed with behavioural tests; S-nitrosylation and AMPAR-mediated synaptic transmission were examined using biochemical assays and electrophysiological recordings, respectively. We found that CFA induced persistent upregulation of AMPAR membrane expression and function in the vmPFC of anxious mice but not in the vmPFC of non-anxious mice. The anxious mice exhibited higher S-nitrosylation of stargazin (an AMPAR-interacting protein) in the vmPFC. Inhibition of S-nitrosylation by bilaterally infusing an exogenous stargazin (C302S) mutant into the vmPFC rescued the surface expression of GluA1 and AMPAR-mediated synaptic transmission as well as the anxiety-like behaviours in CFA-injected mice, even after ibuprofen treatment. Moreover, administration of ZL006, a small molecular inhibitor disrupting the interaction of nNOS and PSD-95 (20 mg·kg-1·d-1, for 5 days, i.p.), significantly reduced nitric oxide production and S-nitrosylation of AMPAR-interacting proteins in the vmPFC, resulting in anxiolytic-like effects in anxious mice after ibuprofen treatment. We conclude that S-nitrosylation is necessary for AMPAR trafficking and function in the vmPFC under chronic inflammatory pain-induced persistent anxiety conditions, and nNOS-PSD-95 inhibitors could be potential anxiolytics specific for chronic inflammatory pain-induced persistent anxiety after analgesic treatment.

(+)-Borneol enantiomer ameliorates epileptic seizure via decreasing the excitability of glutamatergic transmission

Epilepsy is one common brain disorder, which is not well controlled by current pharmacotherapy. In this study we characterized the therapeutic potential of borneol, a plant-derived bicyclic monoterpene compound, in the treatment of epilepsy and elucidated the underlying mechanisms. The anti-seizure potency and properties of borneol were assessed in both acute and chronic mouse epilepsy models. Administration of (+)-borneol (10, 30, 100 mg/kg, i.p.) dose-dependently attenuated acute epileptic seizure in maximal-electroshock seizure (MES) and pentylenetetrazol (PTZ)-induced seizure models without obvious side-effect on motor function. Meanwhile, (+)-borneol administration retarded kindling-induced epileptogenesis and relieved fully kindled seizures. Importantly, (+)-borneol administration also showed therapeutic potential in kainic acid-induced chronic spontaneous seizure model, which was considered as a drug-resistant model. We compared the anti-seizure efficacy of 3 borneol enantiomers in the acute seizure models, and found (+)-borneol being the most satisfying one with long-term anti-seizure effect. In electrophysiological study conducted in mouse brain slices containing the subiculum region, we revealed that borneol enantiomers displayed different anti-seizure mechanisms, (+)-borneol (10 μM) markedly suppressed the high frequency burst firing of subicular neurons and decreased glutamatergic synaptic transmission. In vivo calcium fiber photometry analysis further verified that administration of (+)-borneol (100 mg/kg) inhibited the enhanced glutamatergic synaptic transmission in epilepsy mice. We conclude that (+)-borneol displays broad-spectrum anti-seizure potential in different experimental models via decreasing the glutamatergic synaptic transmission without obvious side-effect, suggesting (+)-borneol as a promising anti-seizure compound for pharmacotherapy in epilepsy.

Inhibition of Prostaglandin E2 Receptor EP3 Attenuates Oxidative Stress and Neuronal Apoptosis Partially by Modulating p38MAPK/FOXO3/Mul1/Mfn2 Pathway after Subarachnoid Hemorrhage in Rats

Oxidative stress and neuronal apoptosis contribute to pathological processes of early brain injury (EBI) after subarachnoid hemorrhage (SAH). Previous studies demonstrated that the inhibition of prostaglandin E2 receptor EP3 suppressed oxidative stress and apoptotic effects after Alzheimer's disease and intracerebral hemorrhage. This study is aimed at investigating the antioxidative stress and antiapoptotic effect of EP3 inhibition and the underlying mechanisms in a rat mode of SAH. A total of 263 Sprague-Dawley male rats were used. SAH was induced by endovascular perforation. Selective EP3 antagonist L798106 was administered intranasally at 1 h, 25 h, and 49 h after SAH induction. EP3 knockout CRISPR and FOXO3 activation CRISPR were administered intracerebroventricularly at 48 h prior to SAH, while selective EP3 agonist sulprostone was administered at 1 h prior to SAH. SAH grade, neurological deficits, western blots, immunofluorescence staining, Fluoro-Jade C staining, TUNEL staining, 8-OHdG staining, and Nissl staining were conducted after SAH. The expression of endogenous PGES2 increased and peaked at 12 h while the expression of EP1, EP2, EP3, EP4, and Mul1 increased and peaked at 24 h in the ipsilateral brain after SAH. EP3 was expressed mainly in neurons. The inhibition of EP3 with L798106 or EP3 KO CRISPR ameliorated the neurological impairments, brain tissue oxidative stress, and neuronal apoptosis after SAH. To examine potential downstream mediators of EP3, we examined the effect of the increased expression of activated FOXO3 following the administration of FOXO3 activation CRISPR. Mechanism studies demonstrated that L798106 treatment significantly decreased the expression of EP3, p-p38, p-FOXO3, Mul1, 4-HNE, Bax, and cleaved caspase-3 but upregulated the expression of Mfn2 and Bcl-2 in SAH rats. EP3 agonist sulprostone or FOXO3 activation CRISPR abolished the neuroprotective effects of L798106 and its regulation on expression of p38MAPK/FOXO3/Mul1/Mfn2 in the ipsilateral brain after SAH. In conclusion, the inhibition of EP3 by L798106 attenuated oxidative stress and neuronal apoptosis partly through p38MAPK/FOXO3/Mul1/Mfn2 pathway post-SAH in rats. EP3 may serve as a potential therapeutic target for SAH patients.

PSD-95 in the anterior cingulate cortex contributes to neuropathic pain by interdependent activation with NR2B

Studies suggest that the scaffolding protein, postsynaptic density protein-95 (PSD-95), is involved in multiple neurological dysfunctions. However, the role of PSD-95 in the anterior cingulate cortex (ACC) in neuropathic pain (NP) has not been investigated. The current study addressed the role of PSD-95 in the ACC in NP and its modulating profile with NMDA receptor subunit 2B (NR2B). The NP model was established by chronic constriction injury (CCI) of the sciatic nerve, and mechanical and thermal tests were used to evaluate behavioral hyperalgesia. Protein expression and distribution were evaluated using immunohistochemistry and western blotting. The results showed that PSD-95 and NR2B were co-localized in neurons in the ACC. After CCI, both PSD-95 and NR2B were upregulated in the ACC. Inhibiting NR2B with Ro 25-6981 attenuated pain hypersensitivity and decreased the over-expression of PSD-95 induced by CCI. Furthermore, intra-ACC administration of PSD-95 antisense oligonucleotide not only attenuated pain hypersensitivity but also downregulated the NR2B level and the phosphorylation of cyclic AMP response element-binding protein. These results demonstrated that PSD-95 in the ACC contributes to NP by interdependent activation of NR2B.

NMDARs mediate peripheral and central sensitization contributing to chronic orofacial pain

Peripheral and central sensitizations of the trigeminal nervous system are the main mechanisms to promote the development and maintenance of chronic orofacial pain characterized by allodynia, hyperalgesia, and ectopic pain after trigeminal nerve injury or inflammation. Although the pathomechanisms of chronic orofacial pain are complex and not well known, sufficient clinical and preclinical evidence supports the contribution of the N-methyl-D-aspartate receptors (NMDARs, a subclass of ionotropic glutamate receptors) to the trigeminal nociceptive signal processing pathway under various pathological conditions. NMDARs not only have been implicated as a potential mediator of pain-related neuroplasticity in the peripheral nervous system (PNS) but also mediate excitatory synaptic transmission and synaptic plasticity in the central nervous system (CNS). In this review, we focus on the pivotal roles and mechanisms of NMDARs in the trigeminal nervous system under orofacial neuropathic and inflammatory pain. In particular, we summarize the types, components, and distribution of NMDARs in the trigeminal nervous system. Besides, we discuss the regulatory roles of neuron-nonneuronal cell/neuron-neuron communication mediated by NMDARs in the peripheral mechanisms of chronic orofacial pain following neuropathic injury and inflammation. Furthermore, we review the functional roles and mechanisms of NMDARs in the ascending and descending circuits under orofacial neuropathic and inflammatory pain conditions, which contribute to the central sensitization. These findings are not only relevant to understanding the underlying mechanisms, but also shed new light on the targeted therapy of chronic orofacial pain.

An Injectable Hydrogel for Treatment of Chronic Neuropathic Pain

Current treatments for chronic neuropathic pain often fall short. A small-molecular compound ZL006 can suppress N-Methyl-D-aspartate receptor (NMDAR)-mediated neuropathic pain behaviors without blocking essential NMDAR function and brings new hope for neuropathic pain therapy. The persistent nature of neuropathic pain mandates the long-term treatment. However, similar to existing analgesics, ZL006 has only a short duration of action. To unleash the therapeutic potential of ZL006, the stability of ZL006 in aqueous solutions is investigated, and a ZL006-incorporated P407-based thermo-responsive injectable hydrogel is developed. The computational analysis is performed to help achieve the desired ZL006-loaded hydrogel system and elucidate the gelation mechanism. The hydrogel matrix can be loaded with ZL006 in an aqueous phase at room temperature without costly specialized equipment and no organic solvent, where the sol is formed and injectable. On subcutaneous administration and subsequent rapid warming to physiological temperature, the sol is converted to a gel. The thermo-responsive hydrogel at body temperature enables the extended release of encapsulated ZL006, and therefore a single subcutaneous injection of ZL006-hydrogel produces a prolonged and stable analgesic action in mice with spinal nerve ligation. Our study provides a practical chronic neuropathic pain therapy and a new perspective on future applications of ZL006. This article is protected by copyright. All rights reserved.

A Compound Mitigates Cancer Pain and Chemotherapy-Induced Neuropathic Pain by Dually Targeting nNOS-PSD-95 Interaction and GABAA Receptor

Metastatic bone pain and chemotherapy-induced peripheral neuropathic pain are the most common clinical symptoms in cancer patients. The current clinical management of these two disorders is ineffective and/or produces severe side effects. The present study employed a dual-target compound named as ZL006-05 and examined the effect of systemic administration of ZL006-05 on RM-1-induced bone cancer pain and paclitaxel-induced neuropathic pain. Intravenous injection of ZL006-05 dose-dependently alleviated RM-1-induced mechanical allodynia, heat hyperalgesia, cold hyperalgesia, and spontaneously ongoing nociceptive responses during both induction and maintenance periods, without analgesic tolerance, affecting basal/acute pain and locomotor function. Similar behavioral results were observed in paclitaxel-induced neuropathic pain. This injection also decreased neuronal and astrocyte hyperactivities in the lumbar dorsal horn after RM-1 tibial inoculation or paclitaxel intraperitoneal injection. Mechanistically, intravenous injection of ZL006-05 potentiated the GABAA receptor agonist-evoked currents in the neurons of the dorsal horn and anterior cingulate cortex and also blocked the paclitaxel-induced increase in postsynaptic density-95-neuronal nitric oxide synthase interaction in dorsal horn. Our findings strongly suggest that ZL006-05 may be a new candidate for the management of cancer pain and chemotherapy-induced peripheral neuropathic pain.