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1.
J Sci Food Agric ; 104(7): 3913-3925, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38345161

RESUMO

BACKGROUND: Food adulteration has long been considered a major problem. It compromises the quality, safety, and nutritional value of food, posing significant risks to public health. Novel techniques are required to control it. RESULTS: A graphene-based T-shaped monopole antenna sensor was tested for its ability to detect adulteration in liquid foods. Mustard oil was the pure reference sample used for product quality analysis. Olive oil and rice bran oil were adulterants added to the pure sample. It was found that the sensor could be immersed easily in the liquid sample and provided precise results. CONCLUSION: The graphene-based T-shaped monopole antenna sensor can be used for the quality assessment of liquid food products and is suitable for real-time monitoring. © 2024 Society of Chemical Industry.


Assuntos
Grafite , Azeite de Oliva/análise , Contaminação de Alimentos/análise , Óleo de Farelo de Arroz/análise
2.
J Ethnopharmacol ; 324: 117704, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38176664

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation and arthritic pain. Sinomenine (SIN), derived from the rhizome of Chinese medical herb Qing Teng (scientific name: Sinomenium acutum (Thunb.) Rehd. Et Wils), has a longstanding use in Chinese traditional medicine for treating rheumatoid arthritis. It has been shown to possess anti-inflammatory, analgesic, and immunosuppressive effects with minimal side-effects clinically. However, the mechanisms governing its effects in treatment of joint pathology, especially on fibroblast-like synoviocytes (FLSs) dysfunction, and arthritic pain remains unclear. AIM: This study aimed to investigate the effect and underlying mechanism of SIN on arthritic joint inflammation and joint FLSs dysfunctions. MATERIALS AND METHODS: Collagen-induced arthritis (CIA) was induced in rats and the therapeutic effects of SIN on joint pathology were evaluated histopathologically. Next, we conducted a series of experiments using LPS-induced FLSs, which were divided into five groups (Naïve, LPS, SIN 10, 20, 50 µg/ml). The expression of inflammatory factors was measured by qPCR and ELISA. The invasive ability of cells was detected by modified Transwell assay and qPCR. Transwell migration and cell scratch assays were used to assess the migration ability of cells. The distribution and content of relevant proteins were observed by immunofluorescence and laser confocal microscopy, as well as Western Blot and qPCR. FLSs were transfected with plasmids (CRMP2 T514A/D) to directly modulate the post-translational modification of CRMP2 protein and downstream effects on FLSs function was monitored. RESULTS: SIN alleviated joint inflammation in rats with CIA, as evidenced by improvement of synovial hyperplasia, inflammatory cell infiltration and cartilage damage, as well as inhibition of pro-inflammatory cytokines release from FLSs induced by LPS. In vitro studies revealed a concentration-dependent suppression of SIN on the invasion and migration of FLSs induced by LPS. In addition, SIN downregulated the expression of cellular CRMP2 that was induced by LPS in FLSs, but increased its phosphorylation at residue T514. Moreover, regulation of pCRMP2 T514 by plasmids transfection (CRMP2 T514A/D) significantly influenced the migration and invasion of FLSs. Finally, SIN promoted nuclear translocation of pCRMP2 T514 in FLSs. CONCLUSIONS: SIN may exert its anti-inflammatory and analgesic effects by modulating CRMP2 T514 phosphorylation and its nuclear translocation of FLSs, inhibiting pro-inflammatory cytokine release, and suppressing abnormal invasion and migration. Phosphorylation of CRMP2 at the T514 site in FLSs may present a new therapeutic target for treating inflammatory joint's destruction and arthritic pain in RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Morfinanos , Sinoviócitos , Ratos , Animais , Fosforilação , Lipopolissacarídeos/farmacologia , Movimento Celular , Artrite Reumatoide/patologia , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/metabolismo , Citocinas/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Fibroblastos , Dor/tratamento farmacológico , Células Cultivadas , Proliferação de Células
3.
Neurobiol Dis ; 183: 106164, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37217103

RESUMO

Phototherapy is an emerging non-pharmacological treatment for depression, circadian rhythm disruptions, and neurodegeneration, as well as pain conditions including migraine and fibromyalgia. However, the mechanism of phototherapy-induced antinociception is not well understood. Here, using fiber photometry recordings of population-level neural activity combined with chemogenetics, we found that phototherapy elicits antinociception via regulation of the ventral lateral geniculate body (vLGN) located in the visual system. Specifically, both green and red lights caused an increase of c-fos in vLGN, with red light increased more. In vLGN, green light causes a large increase in glutamatergic neurons, whereas red light causes a large increase in GABAergic neurons. Green light preconditioning increases the sensitivity of glutamatergic neurons to noxious stimuli in vLGN of PSL mice. Green light produces antinociception by activating glutamatergic neurons in vLGN, and red light promotes nociception by activating GABAergic neurons in vLGN. Together, these results demonstrate that different colors of light exert different pain modulation effects by regulating glutamatergic and GABAergic subpopulations in the vLGN. This may provide potential new therapeutic strategies and new therapeutic targets for the precise clinical treatment of neuropathic pain.


Assuntos
Neuralgia , Nociceptividade , Camundongos , Animais , Nociceptividade/fisiologia , Neurônios GABAérgicos , Corpos Geniculados/fisiologia , Fototerapia , Neuralgia/terapia
4.
Br J Pharmacol ; 180(9): 1267-1285, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36245395

RESUMO

BACKGROUND AND PURPOSE: Postoperative pain occurs in as many as 70% of surgeries performed worldwide. Postoperative pain management still relies on opioids despite their negative consequences, resulting in a public health crisis. Therefore, it is important to develop alternative therapies to treat chronic pain. Natural products derived from medicinal plants are potential sources of novel biologically active compounds for development of safe analgesics. In this study, we screened a library of natural products to identify small molecules that target the activity of voltage-gated sodium and calcium channels that have important roles in nociceptive sensory processing. EXPERIMENTAL APPROACH: Fractions derived from the Native American medicinal plant, Parthenium incanum, were assessed using depolarization-evoked calcium influx in rat dorsal root ganglion (DRG) neurons. Further separation of these fractions yielded a cycloartane-type triterpene identified as argentatin C, which was additionally evaluated using whole-cell voltage and current-clamp electrophysiology, and behavioural analysis in a mouse model of postsurgical pain. KEY RESULTS: Argentatin C blocked the activity of both voltage-gated sodium and low-voltage-activated (LVA) calcium channels in calcium imaging assays. Docking analysis predicted that argentatin C may bind to NaV 1.7-1.9 and CaV 3.1-3.3 channels. Furthermore, argentatin C decreased Na+ and T-type Ca2+ currents as well as excitability in rat and macaque DRG neurons, and reversed mechanical allodynia in a mouse model of postsurgical pain. CONCLUSION AND IMPLICATIONS: These results suggest that the dual effect of argentatin C on voltage-gated sodium and calcium channels supports its potential as a novel treatment for painful conditions.


Assuntos
Canais de Cálcio Tipo T , Canais de Sódio Disparados por Voltagem , Camundongos , Ratos , Animais , Canais de Cálcio Tipo T/metabolismo , Ratos Sprague-Dawley , Sódio/metabolismo , Cálcio/metabolismo , Gânglios Espinais/metabolismo , Dor Pós-Operatória/tratamento farmacológico , Canais de Sódio Disparados por Voltagem/metabolismo
5.
Brain ; 145(8): 2894-2909, 2022 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-35325034

RESUMO

Migraine headache results from activation of meningeal nociceptors, however, the hypothalamus is activated many hours before the emergence of pain. How hypothalamic neural mechanisms may influence trigeminal nociceptor function remains unknown. Stress is a common migraine trigger that engages hypothalamic dynorphin/kappa opioid receptor (KOR) signalling and increases circulating prolactin. Prolactin acts at both long and short prolactin receptor isoforms that are expressed in trigeminal afferents. Following downregulation of the prolactin receptor long isoform, prolactin signalling at the prolactin receptor short isoform sensitizes nociceptors selectively in females. We hypothesized that stress may activate the kappa opioid receptor on tuberoinfundibular dopaminergic neurons to increase circulating prolactin leading to female-selective sensitization of trigeminal nociceptors through dysregulation of prolactin receptor isoforms. A mouse two-hit hyperalgesic priming model of migraine was used. Repeated restraint stress promoted vulnerability (i.e. first-hit priming) to a subsequent subthreshold (i.e. second-hit) stimulus from inhalational umbellulone, a TRPA1 agonist. Periorbital cutaneous allodynia served as a surrogate of migraine-like pain. Female and male KORCre; R26lsl-Sun1-GFP mice showed a high percentage of KORCre labelled neurons co-localized in tyrosine hydroxylase-positive cells in the hypothalamic arcuate nucleus. Restraint stress increased circulating prolactin to a greater degree in females. Stress-primed, but not control, mice of both sexes developed periorbital allodynia following inhalational umbellulone. Gi-DREADD activation (i.e. inhibition through Gi-coupled signalling) in KORCre neurons in the arcuate nucleus also increased circulating prolactin and repeated chemogenetic manipulation of these neurons primed mice of both sexes to umbellulone. Clustered regularly interspaced short palindromic repeats-Cas9 deletion of the arcuate nucleus KOR prevented restraint stress-induced prolactin release in female mice and priming from repeated stress episodes in both sexes. Inhibition of circulating prolactin occurred with systemic cabergoline, a dopamine D2 receptor agonist, blocked priming selectively in females. Repeated restraint stress downregulated the prolactin receptor long isoform in the trigeminal ganglia of female mice. Deletion of prolactin receptor in trigeminal ganglia by nasal clustered regularly interspaced short palindromic repeats-Cas9 targeting both prolactin receptor isoforms prevented stress-induced priming in female mice. Stress-induced activation of hypothalamic KOR increases circulating prolactin resulting in trigeminal downregulation of prolactin receptor long and pain responses to a normally innocuous TRPA1 stimulus. These are the first data that provide a mechanistic link between stress-induced hypothalamic activation and the trigeminal nociceptor effectors that produce trigeminal sensitization and migraine-like pain. This sexually dimorphic mechanism may help to explain female prevalence of migraine. KOR antagonists, currently in phase II clinical trials, may be useful as migraine preventives in both sexes, while dopamine agonists and prolactin/ prolactin receptor antibodies may improve therapy for migraine, and other stress-related neurological disorders, in females.


Assuntos
Transtornos de Enxaqueca , Nociceptores , Animais , Neurônios Dopaminérgicos , Feminino , Hiperalgesia , Hipotálamo , Masculino , Camundongos , Dor , Prolactina , Receptores Opioides kappa , Receptores da Prolactina
6.
Pain ; 163(2): e368-e381, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35029600

RESUMO

ABSTRACT: Mechanistic studies principally focusing on primary afferent nociceptive neurons uncovered the upregulation of collapsin response mediator protein 2 (CRMP2)-a dual trafficking regulator of N-type voltage-gated calcium (Cav2.2) as well as Nav1.7 voltage-gated sodium channels-as a potential determinant of neuropathic pain. Whether CRMP2 contributes to aberrant excitatory synaptic transmission underlying neuropathic pain processing after peripheral nerve injury is unknown. Here, we interrogated CRMP2's role in synaptic transmission and in the initiation or maintenance of chronic pain. In rats, short-interfering RNA-mediated knockdown of CRMP2 in the spinal cord reduced the frequency and amplitude of spontaneous excitatory postsynaptic currents, but not spontaneous inhibitory postsynaptic currents, recorded from superficial dorsal horn neurons in acute spinal cord slices. No effect was observed on miniature excitatory postsynaptic currents and inhibitory postsynaptic currents. In a complementary targeted approach, conditional knockout of CRMP2 from mouse neurons using a calcium/calmodulin-dependent protein kinase II alpha promoter to drive Cre recombinase expression reduced the frequency and amplitude of spontaneous excitatory postsynaptic currents, but not miniature excitatory SCss. Conditional knockout of CRMP2 from mouse astrocytes using a glial fibrillary acidic protein promoter had no effect on synaptic transmission. Conditional knockout of CRMP2 in neurons reversed established mechanical allodynia induced by a spared nerve injury in both male and female mice. In addition, the development of spared nerve injury-induced allodynia was also prevented in these mice. Our data strongly suggest that CRMP2 is a key regulator of glutamatergic neurotransmission driving pain signaling and that it contributes to the transition of physiological pain into pathological pain.


Assuntos
Astrócitos , Neuralgia , Animais , Feminino , Masculino , Camundongos , Neuralgia/genética , Neuralgia/metabolismo , Neurônios/metabolismo , Nociceptividade , Ratos , Transmissão Sináptica
7.
J Pain ; 22(12): 1646-1656, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34157406

RESUMO

Benefits of phototherapy were characterized in multiple diseases including depression, circadian rhythm disruptions, and neurodegeneration. Studies on migraine and fibromyalgia patients revealed that green light-emitting diodes (GLED) exposure provides a pragmatic and safe therapy to manage chronic pain. In rodents, GLED reversed hypersensitivity related to neuropathic pain. However, little is known about the underlying mechanisms of GLED efficacy. Here, we sought to understand how green light modulates the endogenous opioid system. We first characterized how exposure to GLED stimulates release of ß-endorphin and proenkephalin in the central nervous system of male rats. Moreover, by individually editing each of the receptors, we found that µ- and δ-opioid receptors are required for green light's antinociceptive effect in naïve rats and a model of HIV-induced peripheral neuropathy. We investigated how GLED could increase pain thresholds, and explored its potential in reversing hypersensitivity in a model of HIV-related neuropathy. Through behavioral and gene editing approaches, we identified that green light provides antinociception via modulation of the endogenous opioid system in the spinal cord. This work identifies a previously unknown mechanism by which GLED can improve pain management. Clinical translation of these results will advance the development of an innovative therapy devoid of adverse effects. PERSPECTIVE: Development of new pain management therapies, especially for HIV patients, is crucial as long-term opioid prescription is not recommended due to adverse side effects. Green light addresses this necessity. Characterizing the underlying mechanisms of this potentially groundbreaking and safe antinociceptive therapy will advance its clinical translation.


Assuntos
Encefalinas/metabolismo , Neuralgia/metabolismo , Neuralgia/terapia , Fototerapia , Precursores de Proteínas/metabolismo , Medula Espinal/metabolismo , beta-Endorfina/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Ratos
8.
Neurobiol Dis ; 149: 105224, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33359140

RESUMO

The TATA-box binding protein associated factor 1 (TAF1) is part of the TFIID complex that plays a key role during the initiation of transcription. Variants of TAF1 are associated with neurodevelopmental disorders. Previously, we found that CRISPR/Cas9 based editing of the TAF1 gene disrupts the morphology of the cerebral cortex and blunts the expression as well as the function of the CaV3.1 (T-type) voltage gated calcium channel. Here, we tested the efficacy of SAK3 (ethyl 8'-methyl-2', 4-dioxo-2-(piperidin-1-yl)-2'H-spiro [cyclopentane-1, 3'-imidazo [1, 2-a] pyridine]-2-ene-3-carboxylate), a T-type calcium channel enhancer, in an animal model of TAF1 intellectual disability (ID) syndrome. At post-natal day 3, rat pups were subjected to intracerebroventricular (ICV) injection of either gRNA-control or gRNA-TAF1 CRISPR/Cas9 viruses. At post-natal day 21, the rat pups were given SAK3 (0.25 mg/kg, p.o.) or vehicle for 14 days (i.e. till post-natal day 35) and then subjected to behavioral, morphological, and molecular studies. Oral administration of SAK3 (0.25 mg/kg, p.o.) significantly rescued locomotion abnormalities associated with TAF1 gene editing. SAK3 treatment prevented the loss of cortical neurons and GFAP-positive astrocytes observed after TAF1 gene editing. In addition, SAK3 protected cells from apoptosis. SAK3 also restored the Brain-derived neurotrophic factor/protein kinase B/Glycogen Synthase Kinase 3 Beta (BDNF/AKT/GSK3ß) signaling axis in TAF1 edited animals. Finally, SAK3 normalized the levels of three GSK3ß substrates - CaV3.1, FOXP2, and CRMP2. We conclude that the T-type calcium channel enhancer SAK3 is beneficial against the deleterious effects of TAF1 gene-editing, in part, by stimulating the BDNF/AKT/GSK3ß signaling pathway.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Modelos Animais de Doenças , Histona Acetiltransferases/deficiência , Imidazóis/administração & dosagem , Deficiência Intelectual/tratamento farmacológico , Deficiência Intelectual/metabolismo , Compostos de Espiro/administração & dosagem , Fatores Associados à Proteína de Ligação a TATA/deficiência , Fator de Transcrição TFIID/deficiência , Animais , Animais Recém-Nascidos , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Histona Acetiltransferases/genética , Injeções Intraventriculares , Deficiência Intelectual/genética , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética
9.
Cephalalgia ; 41(2): 135-147, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32903062

RESUMO

BACKGROUND: Pharmacological management of migraine can be ineffective for some patients. We previously demonstrated that exposure to green light resulted in antinociception and reversal of thermal and mechanical hypersensitivity in rodent pain models. Given the safety of green light emitting diodes, we evaluated green light as a potential therapy in patients with episodic or chronic migraine. MATERIAL AND METHODS: We recruited (29 total) patients, of whom seven had episodic migraine and 22 had chronic migraine. We used a one-way cross-over design consisting of exposure for 1-2 hours daily to white light emitting diodes for 10 weeks, followed by a 2-week washout period followed by exposure for 1-2 hours daily to green light emitting diodes for 10 weeks. Patients were allowed to continue current therapies and to initiate new treatments as directed by their physicians. Outcomes consisted of patient-reported surveys. The primary outcome measure was the number of headache days per month. Secondary outcome measures included patient-reported changes in the intensity and frequency of the headaches over a two-week period and other quality of life measures including ability to fall and stay asleep, and ability to perform work. Changes in pain medications were obtained to assess potential reduction. RESULTS: When seven episodic migraine and 22 chronic migraine patients were analyzed as separate cohorts, white light emitting diodes produced no significant change in headache days in either episodic migraine or chronic migraine patients. Combining data from the episodic migraine and chronic migraine groups showed that white light emitting diodes produced a small, but statistically significant reduction in headache days from (days ± SEM) 18.2 ± 1.8 to 16.5 ± 2.01 days. Green light emitting diodes resulted in a significant decrease in headache days from 7.9 ± 1.6 to 2.4 ± 1.1 and from 22.3 ± 1.2 to 9.4 ± 1.6 in episodic migraine and chronic migraine patients, respectively. While some improvement in secondary outcomes was observed with white light emitting diodes, more secondary outcomes with significantly greater magnitude including assessments of quality of life, Short-Form McGill Pain Questionnaire, Headache Impact Test-6, and Five-level version of the EuroQol five-dimensional survey without reported side effects were observed with green light emitting diodes. Conclusions regarding pain medications reduction with green light emitting diode exposure were not possible. No side effects of light therapy were reported. None of the patients in the study reported initiation of new therapies. DISCUSSION: Green light emitting diodes significantly reduced the number of headache days in people with episodic migraine or chronic migraine. Additionally, green light emitting diodes significantly improved multiple secondary outcome measures including quality of life and intensity and duration of the headache attacks. As no adverse events were reported, green light emitting diodes may provide a treatment option for those patients who prefer non-pharmacological therapies or may be considered in complementing other treatment strategies. Limitations of this study are the small number of patients evaluated. The positive data obtained support implementation of larger clinical trials to determine possible effects of green light emitting diode therapy.This study is registered with clinicaltrials.gov under NCT03677206.


Assuntos
Transtornos de Enxaqueca , Qualidade de Vida , Estudos Cross-Over , Cefaleia , Humanos , Luz , Transtornos de Enxaqueca/terapia , Dor , Resultado do Tratamento
10.
Pain Med ; 22(1): 118-130, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33155057

RESUMO

OBJECTIVE: Fibromyalgia is a functional pain disorder in which patients suffer from widespread pain and poor quality of life. Fibromyalgia pain and its impact on quality of life are not effectively managed with current therapeutics. Previously, in a preclinical rat study, we demonstrated that exposure to green light-emitting diodes (GLED) for 8 hours/day for 5 days resulted in antinociception and reversal of thermal and mechanical hypersensitivity associated with models of injury-related pain. Given the safety of GLED and the ease of its use, our objective is to administer GLED as a potential therapy to patients with fibromyalgia. DESIGN: One-way crossover clinical trial. SETTING: United States. METHOD: We enrolled 21 adult patients with fibromyalgia recruited from the University of Arizona chronic pain clinic who were initially exposed to white light-emitting diodes and then were crossed over to GLED for 1 to 2 hours daily for 10 weeks. Data were collected by using paper surveys. RESULTS: When patients were exposed to GLED, but not white light-emitting diodes, they reported a significant reduction in average pain intensity on the 10-point numeric pain scale. Secondary outcomes were assessed by using the EQ-5D-5L survey, Short-Form McGill Pain Questionnaire, and Fibromyalgia Impact Questionnaire and were also significantly improved in patients exposed to GLED. GLED therapy was not associated with any measured side effects in these patients. CONCLUSION: Although the mechanism by which GLED elicits pain reduction is currently being studied, these results supporting its efficacy and safety merit a larger clinical trial.


Assuntos
Fibromialgia , Adulto , Animais , Fibromialgia/terapia , Humanos , Dor , Medição da Dor , Qualidade de Vida , Ratos , Inquéritos e Questionários , Resultado do Tratamento
11.
Mol Brain ; 13(1): 73, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393368

RESUMO

Chronic pain can be the result of an underlying disease or condition, medical treatment, inflammation, or injury. The number of persons experiencing this type of pain is substantial, affecting upwards of 50 million adults in the United States. Pharmacotherapy of most of the severe chronic pain patients includes drugs such as gabapentinoids, re-uptake blockers and opioids. Unfortunately, gabapentinoids are not effective in up to two-thirds of this population and although opioids can be initially effective, their long-term use is associated with multiple side effects. Therefore, there is a great need to develop novel non-opioid alternative therapies to relieve chronic pain. For this purpose, we screened a small library of natural products and their derivatives in the search for pharmacological inhibitors of voltage-gated calcium and sodium channels, which are outstanding molecular targets due to their important roles in nociceptive pathways. We discovered that the acetylated derivative of the ent-kaurane diterpenoid, geopyxin A, 1-O-acetylgeopyxin A, blocks voltage-gated calcium and tetrodotoxin-sensitive voltage-gated sodium channels but not tetrodotoxin-resistant sodium channels in dorsal root ganglion (DRG) neurons. Consistent with inhibition of voltage-gated sodium and calcium channels, 1-O-acetylgeopyxin A reduced reduce action potential firing frequency and increased firing threshold (rheobase) in DRG neurons. Finally, we identified the potential of 1-O-acetylgeopyxin A to reverse mechanical allodynia in a preclinical rat model of HIV-induced sensory neuropathy. Dual targeting of both sodium and calcium channels may permit block of nociceptor excitability and of release of pro-nociceptive transmitters. Future studies will harness the core structure of geopyxins for the generation of antinociceptive drugs.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Gânglios Espinais/efeitos dos fármacos , Limoninas/farmacologia , Neuralgia/tratamento farmacológico , Preparações Farmacêuticas/administração & dosagem , Bloqueadores dos Canais de Sódio/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Feminino , Gânglios Espinais/citologia , Gânglios Espinais/fisiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Hiperalgesia/virologia , Limoninas/administração & dosagem , Limoninas/química , Neuralgia/metabolismo , Neuralgia/virologia , Nociceptores/efeitos dos fármacos , Preparações Farmacêuticas/metabolismo , Ratos , Ratos Sprague-Dawley , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/fisiologia , Tetrodotoxina/farmacologia
12.
ACS Chem Neurosci ; 10(12): 4834-4846, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31697467

RESUMO

Naringenin (2S)-5,7-dihydroxy-2-(4-hydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-4-one is a natural flavonoid found in fruits from the citrus family. Because (2S)-naringenin is known to racemize, its bioactivity might be related to one or both enantiomers. Computational studies predicted that (2R)-naringenin may act on voltage-gated ion channels, particularly the N-type calcium channel (CaV2.2) and the NaV1.7 sodium channel-both of which are key for pain signaling. Here we set out to identify the possible mechanism of action of naringenin. Naringenin inhibited depolarization-evoked Ca2+ influx in acetylcholine-, ATP-, and capsaicin-responding rat dorsal root ganglion (DRG) neurons. This was corroborated in electrophysiological recordings from DRG neurons. Pharmacological dissection of each of the voltage-gated Ca2+ channels subtypes could not pinpoint any selectivity of naringenin. Instead, naringenin inhibited NaV1.8-dependent and tetrodotoxin (TTX)-resistant while sparing tetrodotoxin sensitive (TTX-S) voltage-gated Na+ channels as evidenced by the lack of further inhibition by the NaV1.8 blocker A-803467. The effects of the natural flavonoid were validated ex vivo in spinal cord slices where naringenin decreased both the frequency and amplitude of sEPSC recorded in neurons within the substantia gelatinosa. The antinociceptive potential of naringenin was evaluated in male and female mice. Naringenin had no effect on the nociceptive thresholds evoked by heat. Naringenin's reversed allodynia was in mouse models of postsurgical and neuropathic pain. Here, driven by a call by the National Center for Complementary and Integrative Health's strategic plan to advance fundamental research into basic biological mechanisms of the action of natural products, we advance the antinociceptive potential of the flavonoid naringenin.


Assuntos
Analgésicos/farmacologia , Flavanonas/farmacologia , Gânglios Espinais/citologia , Canal de Sódio Disparado por Voltagem NAV1.8/efeitos dos fármacos , Nociceptividade/efeitos dos fármacos , Células Receptoras Sensoriais/efeitos dos fármacos , Bloqueadores dos Canais de Sódio/farmacologia , Sódio/metabolismo , Analgésicos/química , Analgésicos/uso terapêutico , Animais , Canais de Cálcio/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Flavanonas/química , Flavanonas/metabolismo , Flavanonas/uso terapêutico , Hiperalgesia/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Neuralgia/tratamento farmacológico , Dor Pós-Operatória/tratamento farmacológico , Conformação Proteica , Mapeamento de Interação de Proteínas , Ratos , Ratos Sprague-Dawley , Células Receptoras Sensoriais/classificação , Células Receptoras Sensoriais/metabolismo , Bloqueadores dos Canais de Sódio/química , Bloqueadores dos Canais de Sódio/uso terapêutico , Organismos Livres de Patógenos Específicos , Relação Estrutura-Atividade
13.
Channels (Austin) ; 13(1): 498-504, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31680630

RESUMO

We have previously reported that the microtubule-associated collapsin response mediator protein 2 (CRMP2) is necessary for the expression of chronic pain. CRMP2 achieves this control of nociceptive signaling by virtue of its ability to regulate voltage-gated calcium and sodium channels. To date, however, no drugs exist that target CRMP2. Recently, the small molecule edonerpic maleate (1 -{3-[2-(1-benzothiophen-5-yl)ethoxy]propyl}azetidin-3-ol maleate), a candidate therapeutic for Alzheimer's disease was reported to be a novel CRMP2 binding compound with the potential to decrease its phosphorylation level in cortical tissues in vivo. Here we sought to determine the mechanism of action of edonerpic maleate and test its possible effect in a rodent model of chronic pain. We observed: (i) no binding between human CRMP2 and edonerpic maleate; (ii) edonerpic maleate had no effect on CRMP2 expression and phosphorylation in dorsal root ganglion (DRG) neurons; (iii) edonerpic maleate-decreased calcium but increased sodium current density in DRG neurons; and (iv) edonerpic maleate was ineffective in reversing post-surgical allodynia in male and female mice. Thus, while CRMP2 inhibiting compounds remain a viable strategy for developing new mechanism-based pain inhibitors, edonerpic maleate is an unlikely candidate.


Assuntos
Hiperalgesia/tratamento farmacológico , Maleatos/administração & dosagem , Proteínas do Tecido Nervoso/antagonistas & inibidores , Tiofenos/administração & dosagem , Animais , Cálcio/metabolismo , Avaliação Pré-Clínica de Medicamentos , Feminino , Gânglios Espinais/metabolismo , Humanos , Hiperalgesia/genética , Hiperalgesia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fosforilação
14.
Indian Pediatr ; 56(5): 369-373, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31102378

RESUMO

OBJECTIVE: To document the impact of neonatal resuscitation capacity building of birth attendants at district and sub-district level on fresh stillbirth within the public health system in India. DESIGN: An implementation research using pre-post study design. SETTING: 3 high-infant and neonatal mortality districts (Gonda, Aligarh and Raebareli) of Uttar Pradesh, India. PARTICIPANTS: Pregnant women who delivered at the health facilities and their newborns. INTERVENTIONS: An intervention package with (i) training on essential newborn care resuscitation; (ii) skill laboratories establishment for peer-interactive learning; (iii) better documentation; and (iv) supportive supervision was implemented at all health facilities in the districts. MAIN OUTCOME MEASURES: Impact on fresh stillbirth rates and resuscitation practices were documented at 42 health facilities (Gonda-17, Aligarh-8 and Raebareli-17) over 12-18 months. RESULTS: Out of the 3.3% (4431/133627) newborns requiring resuscitation, 58.5% (n=2599) were completely revived, 19% (n=842) had some features of hypoxic insult after birth and 1.4% (n=62) were stillbirths. There was 15.6% reduction in still birth rate in the three districts with the intervention package. CONCLUSIONS: The reduction in still birth rate and improvement in newborn resuscitation efforts in the three districts indicated feasibility of implementation and scalability of the intervention package. However sustenance of the impact over longer period needs documentation.


Assuntos
Fortalecimento Institucional , Educação Médica Continuada/métodos , Educação Continuada em Enfermagem/métodos , Hospitais de Distrito , Tocologia/educação , Ressuscitação/educação , Natimorto/epidemiologia , Educação Médica Continuada/organização & administração , Educação Continuada em Enfermagem/organização & administração , Estudos de Viabilidade , Feminino , Humanos , Índia/epidemiologia , Lactente , Mortalidade Infantil , Recém-Nascido , Avaliação de Processos e Resultados em Cuidados de Saúde , Gravidez
15.
Pain ; 160(1): 117-135, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30169422

RESUMO

The Federal Pain Research Strategy recommended development of nonopioid analgesics as a top priority in its strategic plan to address the significant public health crisis and individual burden of chronic pain faced by >100 million Americans. Motivated by this challenge, a natural product extracts library was screened and identified a plant extract that targets activity of voltage-gated calcium channels. This profile is of interest as a potential treatment for neuropathic pain. The active extract derived from the desert lavender plant native to southwestern United States, when subjected to bioassay-guided fractionation, afforded 3 compounds identified as pentacyclic triterpenoids, betulinic acid (BA), oleanolic acid, and ursolic acid. Betulinic acid inhibited depolarization-evoked calcium influx in dorsal root ganglion (DRG) neurons predominantly through targeting low-voltage-gated (Cav3 or T-type) and CaV2.2 (N-type) calcium channels. Voltage-clamp electrophysiology experiments revealed a reduction of Ca, but not Na, currents in sensory neurons after BA exposure. Betulinic acid inhibited spontaneous excitatory postsynaptic currents and depolarization-evoked release of calcitonin gene-related peptide from lumbar spinal cord slices. Notably, BA did not engage human mu, delta, or kappa opioid receptors. Intrathecal administration of BA reversed mechanical allodynia in rat models of chemotherapy-induced peripheral neuropathy and HIV-associated peripheral sensory neuropathy as well as a mouse model of partial sciatic nerve ligation without effects on locomotion. The broad-spectrum biological and medicinal properties reported, including anti-HIV and anticancer activities of BA and its derivatives, position this plant-derived small molecule natural product as a potential nonopioid therapy for management of chronic pain.


Assuntos
Canais de Cálcio Tipo N/metabolismo , Canais de Cálcio Tipo T/metabolismo , Infecções por HIV/complicações , Neuralgia/tratamento farmacológico , Neuralgia/etiologia , Paclitaxel/toxicidade , Triterpenos/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Células CHO , Cricetulus , Diprenorfina/farmacocinética , Modelos Animais de Doenças , Feminino , Gânglios Espinais/citologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Triterpenos Pentacíclicos , Traumatismos dos Nervos Periféricos/induzido quimicamente , Traumatismos dos Nervos Periféricos/complicações , Traumatismos dos Nervos Periféricos/etiologia , Traumatismos dos Nervos Periféricos/virologia , Ratos , Ratos Sprague-Dawley , Trítio/farmacocinética , Ácido Betulínico
17.
Pain ; 158(2): 347-360, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28092651

RESUMO

Treatments for chronic pain are inadequate, and new options are needed. Nonpharmaceutical approaches are especially attractive with many potential advantages including safety. Light therapy has been suggested to be beneficial in certain medical conditions such as depression, but this approach remains to be explored for modulation of pain. We investigated the effects of light-emitting diodes (LEDs), in the visible spectrum, on acute sensory thresholds in naive rats as well as in experimental neuropathic pain. Rats receiving green LED light (wavelength 525 nm, 8 h/d) showed significantly increased paw withdrawal latency to a noxious thermal stimulus; this antinociceptive effect persisted for 4 days after termination of last exposure without development of tolerance. No apparent side effects were noted and motor performance was not impaired. Despite LED exposure, opaque contact lenses prevented antinociception. Rats fitted with green contact lenses exposed to room light exhibited antinociception arguing for a role of the visual system. Antinociception was not due to stress/anxiety but likely due to increased enkephalins expression in the spinal cord. Naloxone reversed the antinociception, suggesting involvement of central opioid circuits. Rostral ventromedial medulla inactivation prevented expression of light-induced antinociception suggesting engagement of descending inhibition. Green LED exposure also reversed thermal and mechanical hyperalgesia in rats with spinal nerve ligation. Pharmacological and proteomic profiling of dorsal root ganglion neurons from green LED-exposed rats identified changes in calcium channel activity, including a decrease in the N-type (CaV2.2) channel, a primary analgesic target. Thus, green LED therapy may represent a novel, nonpharmacological approach for managing pain.


Assuntos
Analgésicos/uso terapêutico , Dor Crônica/terapia , Fototerapia/métodos , Animais , Canais de Cálcio Tipo N/genética , Canais de Cálcio Tipo N/metabolismo , Cor , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Feminino , Gânglios Espinais/citologia , Gânglios Espinais/efeitos dos fármacos , Masculino , Bulbo , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Limiar da Dor/efeitos da radiação , Estimulação Física/efeitos adversos , Células do Corno Posterior/efeitos dos fármacos , Células do Corno Posterior/efeitos da radiação , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Tempo de Reação/efeitos da radiação
18.
Transl Neurosci ; 4(3)2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24260711

RESUMO

Vertebrate brains share many features in common. Early in development, both the hindbrain and diencephalon are built similarly. Only later in time do differences in morphology occur. Factors that could potentially influence such changes include certain physiological properties of neurons. As an initial step to investigate this problem, embryonic Alligator brain neurons were cultured and calcium responses were characterized. The present report is the first to document culture of Alligator brain neurons in artificial cerebrospinal fluid (ACSF) as well as in standard mammalian tissue culture medium supplemented with growth factors. Alligator brain neuron cultures were viable for at least 1 week with unipolar neurites emerging by 24 hours. Employing Fura-2 AM, robust depolarization-induced calcium influx, was observed in these neurons. Using selective blockers of the voltage-gated calcium channels, the contributions of N-, P/Q-, R-, T-, and L-type channels in these neurons were assessed and their presence documented. Lastly, Alligator brain neurons were challenged with an excitotoxic stimulus (glutamate + glycine) where delayed calcium deregulation could be prevented by a classical NMDA receptor antagonist.

19.
Indian J Pediatr ; 77(3): 291-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20431966

RESUMO

Health research can be utilized to improve the policies, interventions and outputs of the health systems, and ultimately the health of individuals and population. This requires systematic evaluation of evidence and its integration into national policies and programs after suitable adoption at the local level. It has been noted that there has been limited focus upon strengthening health research in India, due to weak research systems or institutional mechanisms, lack of trained human resources and enabling environment, absence of well defined priorities, perceived low quality of research, and inadequate funding. Though various vertical and integrated health programs for improving child survival in the country have been introduced, the decline in child mortality has been excessively slow. Operational research, a sub theme of health research, which uses systematic research techniques to provide evidence to the policymakers and program managers, can be used to assess programmatic issues and improve their effectiveness. This article analyzes the current situation of health research in India, describes briefly the process of operational research, and summarizes the areas of programmatic concern and priority topics for future research in five key fields of child health (Newborn health, Immunization, Malnutrition, Disease prevention and control, health systems strengthening). Finally, it outlines the immediate need of strengthening health research system in the country for improving child survival through increased funding, development of institutional mechanisms, building pool of talented researchers and provision of an enabling environment, to facilitate health and operational research in a scientifically credible manner and to ensure wider dissemination of results.


Assuntos
Proteção da Criança , Prioridades em Saúde , Pesquisa sobre Serviços de Saúde , Criança , Serviços de Saúde da Criança , Humanos , Índia
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