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1.
In Vivo ; 37(1): 149-162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36593026

RESUMO

BACKGROUND/AIM: This study evaluated the effect of blueberry leaf hot water extract (BLEx) on Sjögren's syndrome (SS)-like lacrimal hyposecretion in male non-obese diabetic (NOD) mice. MATERIALS AND METHODS: NOD or BALB/c mice were fed 1% BLEx or control (AIN-93G) for 2 weeks from the age of 4 to 6 weeks. Pilocarpine-induced tear volume was measured using a phenol red-impregnated thread. The lacrimal glands were evaluated histologically by H&E staining. The IL-1ß and TNF-α levels in the lacrimal gland tissue were measured by ELISA. The mRNA expression levels of secretion-related proteins were measured by real-time PCR. LC3 I/II and arginase 1 expression levels were measured by western blot. RESULTS: After feeding with BLEx, pilocarpine-induced tear secretion in NOD mice was increased. In contrast, the mRNA expression levels of the cholinergic muscarinic M3 receptor, aquaporin 5, and ion channels related to lacrimal secretion were not changed by BLEx administration. In addition, the protein expression of arginase 1, which was recently reported to be involved in tear hyposecretion in NOD mice, was also not improved by BLEx administration. Although infiltration in the lacrimal gland of NOD mice was not decreased, the levels of TNF-α and the autophagy-related protein LC3 were significantly suppressed by BLEx treatment. CONCLUSION: BLEx treatment may ameliorate lacrimal hyposecretion in NOD mice by delaying the progression of autoimmune disease by suppressing autophagy in lacrimal glands.


Assuntos
Mirtilos Azuis (Planta) , Diabetes Mellitus Experimental , Aparelho Lacrimal , Síndrome de Sjogren , Masculino , Animais , Camundongos , Síndrome de Sjogren/tratamento farmacológico , Aparelho Lacrimal/metabolismo , Aparelho Lacrimal/patologia , Camundongos Endogâmicos NOD , Mirtilos Azuis (Planta)/genética , Arginase/metabolismo , Arginase/farmacologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Pilocarpina/metabolismo , Pilocarpina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Extratos Vegetais/farmacologia , RNA Mensageiro/genética , Modelos Animais de Doenças
2.
Braz. J. Biol. ; 83: 1-10, 2023. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-765596

RESUMO

Only few studies have focus on animals that received Pilocarpine (Pilo) and did not develop behavioral status epilepticus (SE) and, whether they may become epileptic in the model's chronic phase. Previews works observed mossy fiber sprouting in the hippocampus of Non-SE (NSE) rats, while others observed spontaneous and recurrent seizures (SRS) 6 - 8 months after animals received Pilo. It is known that neuronal excitability is influenced by female hormones, as well as, the occurrence of SE in castrated and non-castrated female rats. However, it is not known whether females that received Pilo and did not show SE, may have SRS. The aim of this work was to investigate whether castrated and non-castrated female rats that did not show behavioral SE after Pilo, will develop SRS in the following one-year. For that, animals received 360 mg/kg of Pilo and were video monitored for 12 months. SE females from castrated and non-castrated groups became epileptic since the first month after drug injection. Epileptic behaviors were identified watching video monitoring recordings in the fast speed. Castrated and Non castrated NSE animals showed behaviors resembling seizures described by Racine Scale stages 1 - 3. Motor alterations showed by NSE groups could be observed only when recordings were analyzed in slow speed. In addition, behavioral manifestations as, rhythmic head movements, sudden head movements, whole body movements and immobility were also observed in both, SE and NSE groups. We concluded that NSE female rats may have become epileptic. Adding to it, slow speed analysis of motor alterations was essential for the observation of NSE findings, which suggests that possibly many motor alterations have been underestimated in epilepsy experimental research.(AU)


Poucos são os estudos com foco em animais que receberam Pilocarpina (Pilo) e não desenvolveram status epilepticus (SE) comportamental e, se os mesmos se tornarão epilépticos na fase crônica do modelo. Autores observaram o brotamento das fibras musgosas no hipocampo de ratos Não-SE (NSE), enquanto outros observaram crises espontâneas e recorrentes (CER) 6 - 8 meses após receberam a droga. A excitabilidade neuronal é influenciada pelos hormônios femininos e, da mesma forma, a ocorrência de SE em ratas castradas e não-castradas. Entretanto, não é sabido se as fêmeas que não apresentam SE terão CER. O objetivo deste trabalho foi investigar se fêmeas castradas e não castradas que não tiveram SE comportamental após a injeção de Pilo desenvolverão CER dentro de um ano. Para isto, os animais receberam 360 mg/kg de Pilo e foram videomonitorados por 12 meses. As fêmeas SE castradas e não-castradas se tornaram epilépticas desde o primeiro mês pós Pilo. O comportamento epiléptico foi identificado assistindo as gravações na velocidade rápida. As fêmeas NSE castradas e não-castradas apresentaram comportamentos similares aos estágios 1 - 3 da Escala de Racine. As alterações motoras nestes grupos (NSE) foram observadas apenas quando as videomonitoração foi analisada na velocidade lenta. Além destas, manifestações comportamentais como movimentos rítmicos da cabeça, movimentos súbitos da cabeça, movimentos de todo o corpo e imobilidade também foram observadas em ambos grupos, SE e NSE. Concluímos que as fêmeas NE podem ter se tornado epilépticas. Adicionado a isto, a análise das alterações motoras na velocidade lenta foi essencial para a observação dos achados das fêmeas NSE, o que sugere que possivelmente muitas alterações motoras têm sido subestimados na pesquisa em epilepsia experimental.(AU)


Assuntos
Animais , Feminino , Ratos , Epilepsia/induzido quimicamente , Epilepsia/veterinária , Pilocarpina/farmacologia , Pilocarpina/administração & dosagem , Pilocarpina/efeitos adversos , Modelos Animais
3.
Eur J Pharmacol ; 939: 175453, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516936

RESUMO

Status epilepticus (SE) triggered by lithium-pilocarpine is a model of epileptogenesis widely used in rats, reproducing many of the pathological features of human temporal lobe epilepsy (TLE). After the SE, a silent period takes place that precedes the occurrence of recurrent spontaneous seizures. This latent stage is characterized by brain glucose hypometabolism and intense neuronal damage, especially at the hippocampus. Importantly, interictal hypometabolism in humans is a predictive marker of epileptogenesis, being correlated to the extent and severity of neuronal damage. Among the potential mechanisms underpinning glucose metabolism impairment and the subsequent brain damage, a reduction of cerebral blood flow has been proposed. Accordingly, our goal was to evaluate the potential beneficial effects of naftidrofuryl (25 mg/kg i.p., twice after the insult), a vasodilator drug currently used for circulatory insufficiency-related pathologies. Thus, we measured the effects of naftidrofuryl on the short-term brain hypometabolism and hippocampal damage induced by SE in rats. 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET) neuroimaging along with various neurohistochemical assays aimed to assess brain damage were performed. SE led to both severe glucose hypometabolism in key epilepsy-related areas and hippocampal neuronal damage. Although naftidrofuryl showed no anticonvulsant properties, it ameliorated the short-term brain hypometabolism induced by pilocarpine. Strikingly, the latter was neither accompanied by neuroprotective nor by anti-inflammatory effects. We suggest that naftidrofuryl, by acutely enhancing brain blood flow around the time of SE improves the brain metabolic state but this effect is not enough to protect from the damage induced by SE.


Assuntos
Nafronil , Estado Epiléptico , Humanos , Ratos , Animais , Pilocarpina/farmacologia , Lítio/farmacologia , Nafronil/metabolismo , Nafronil/farmacologia , Vasodilatadores/farmacologia , Neuroproteção , Glucose/metabolismo , Modelos Animais de Doenças , Encéfalo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/tratamento farmacológico , Hipocampo , Convulsões/metabolismo
4.
Indian J Ophthalmol ; 70(12): 4174-4179, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36453309

RESUMO

Purpose: Indication of laser peripheral iridotomy (LPI) is often conjectural due to dependency on gonioscopy and strict dichotomous classification of occludability. Indentation gonioscopy is the gold standard but is under-utilized for various reasons. The prevalence of primary angle closure disease (PACD) in eastern India is 1.5-1.9%, with a 22% five-year progression rate. Many angle closure patients may go blind without timely diagnosis and iridotomy. General ophthalmologists need alternate, validated methods for diagnoses. Pilocarpine eye drop causes miosis, and flattens the iris, producing angle changes detectable by spectral domain optical coherence tomography (SD-OCT). We hypothesized that the amount of angle change may be a suitable indicator for iridotomy. Methods: Our prospective cross-sectional single-masked observational study evaluated pilocarpine-induced changes in angle parameters detected by SD-OCT. Out of 372 patients enrolled, 273 patients (539 eyes) remained, with a mean age of 48.6 years (SD = 10.36). All eyes were graded by the Van Herick (VH) method, gonioscopy, and anterior segment (AS) SD-OCT and reassessed after pilocarpine drops. Results: The sensitivity and specificity of tomography measurements against gonioscopy grades were 61% and 85%, respectively. The receiver operating characteristic (ROC) curve was 0.85. Pilocarpine-induced angle widening was significant in gonioscopically narrower angles. Low Van Herick grades (217 eyes), narrow gonioscopy grades (238 eyes), and a narrow OCT angle value (165 eyes) were candidates for iridotomy. Conclusion: Our study results showed that pilocarpine-induced angle widening detected by SD-OCT could be a strong objective indicator for LPI.


Assuntos
Pilocarpina , Tomografia de Coerência Óptica , Humanos , Pessoa de Meia-Idade , Pilocarpina/farmacologia , Estudos Transversais , Estudos Prospectivos , Iris/diagnóstico por imagem , Iris/cirurgia , Câmara Anterior/diagnóstico por imagem , Câmara Anterior/cirurgia , Lasers
5.
Pak J Biol Sci ; 25(10): 929-937, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36404747

RESUMO

<b>Background and Objective:</b> Epilepsy is one of the normal neurological problems that came about because of strange electrical movements and prompt serious and far-reaching cell misfortune in the mind. This study aimed to investigate if a nano-Chitosan formulation loaded with bovine milk lactoperoxidase (LPO) and lactoferrin (LF) could prevent Lithium Chloride/Pilocarpine-induced epilepsy in rats or not. <b>Materials and Methods:</b> Adult male rats (200-250 g) were partitioned into four groups (8 animals each) as follows: Group (1) Normal rats served as control group and received saline orally, group (2) Normal rats ingested with a daily oral dose of LPO and LF-NPS formulation at 50 mg kg<sup></sup><sup>1</sup>, group (3) Pilocarpine-induced epileptic rats and group (4) Epilepsy-modeled rats were treated with LPO+LF NPs (50 mg/kg/day, orally) for 6 weeks. <b>Results:</b> The results revealed that the administration of LPO+LF-NPs markedly improved the induced-epilepsy disorders, this was monitored from the significant reduction in the values of caspase-3, TNF-α, IL-1ß, CD4<sup>+</sup>, MDA and NO coupled with remarkable raise in AchE-ase, dopamine, serotonin, SOD and GPx, CAT and GSH values in both brain regions. <b>Conclusion:</b> This study supported the anti-epilepsy features of LPO+LF-NPS against Lithium Chloride/Pilocarpine-induced epilepsy in rats through the improvement of the immune response, reduction of inflammation and restoration of the impaired oxidative stress status.


Assuntos
Cloreto de Lítio , Pilocarpina , Animais , Ratos , Masculino , Pilocarpina/farmacologia , Cloreto de Lítio/farmacologia , Encéfalo , Estresse Oxidativo , Anticonvulsivantes
6.
Braz J Med Biol Res ; 55: e12381, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36350974

RESUMO

Glial cells have been implicated in temporal lobe epilepsy in humans and in its models. Astrocytes are lost in several brain regions after acute seizures induced by pilocarpine and may suffer hyperplasia at subsequent time points. This study investigated the effect of N-methyl-(2S,4R)-trans-4-hydroxy-L-proline (NMP) on astrocytes exposed to cytotoxic concentrations of pilocarpine. Astrocytes were incubated with pilocarpine (half maximal inhibitory concentration (IC50)=31.86 mM) for 24 h. Afterwards, they were treated with NMP at concentrations ranging from 3.12 to 100 µg/mL for 24 h. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cytoplasmic reactive oxygen species (ROS) and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry using 2',7'-dichlorofluorescein diacetate (DCFH-DA) and rhodamine-123 (Rho123), respectively. Expression of glial fibrillary acidic protein (GFAP) and voltage-dependent anion channel-1 (VDAC-1) were measured by western blot. Pilocarpine significantly decreased cell viability and mitochondrial potential and increased ROS concentration significantly by 6.7 times compared to the control. NMP concentrations ≥25 µg/mL protected astrocytes against pilocarpine-induced injury in a concentration-dependent manner. Concomitantly, NMP reduced cytoplasmic ROS accumulation to 27.3, 24.8, and 12.3% in the groups treated with 25, 50, and 100 µg/mL NMP, respectively. NMP also protected mitochondria from pilocarpine-induced depolarization. These effects were associated with improvement of pilocarpine-induced GFAP and VDAC-1 overexpression, which are important biomarkers of astrocyte dysfunction. In conclusion, the improvement of ROS accumulation, VDAC-1 overexpression, and mitochondrial depolarization are possible mechanisms of the NMP protective action on reactive astrocytes.


Assuntos
Pilocarpina , Sapotaceae , Humanos , Pilocarpina/farmacologia , Astrócitos , Espécies Reativas de Oxigênio/metabolismo , Sapotaceae/metabolismo
7.
Cell Mol Biol (Noisy-le-grand) ; 68(6): 73-78, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36227674

RESUMO

Corneal stability is essential for contact lenses and refractive surgery. It seems that paralyzing eye drops or expansion of the ciliary muscle affect the radius of curvature and the strength of the cornea, and this effect is to increase the strength of the cornea during muscle spasm and decrease it in the relaxed state of the muscle. On the other hand, different factors (such as contact lens wear, ocular surface disorders, trauma, dry eye, and immunosuppression) could alter the immune defense mechanisms of the outer eye and permit microorganisms to invade the cornea. Therefore, the present study compared Pilocarpine and tropicamide drop on corneal topography and their effect on IL-6 and TNF-α levels in tear. This prospective study was performed on sixty normal and healthy eyes of sixty volunteers with a mean age of 38.19 years and without any ocular pathology. Volunteers were divided into two groups of thirty. In the first group, corneal topography of both eyes was measured before and 30 minutes after instillation of topical tropicamide 1% in only one eye. The other eye was the control eye, and no drop was given. The same routine was performed in the second group, except that subject received one drop of Pilocarpine 2% in one eye. Statistical comparison between groups for the central corneal power, corneal radius, and corneal astigmatism was performed using paired t-test. IL-6 and TNF-α levels in tear were analyzed using two Luminex commercial assays with Bio-Plex 200TM System (Bio-Rad, Hercules, California, USA). In group 1, no significant changes were found in corneal radius, power, and astigmatism. However, in group 2 subjects who received pilocarpine eye drops, the mean corneal radius value decreased significantly by 0.05 mm. The mean corneal power increased by +0.32 D. There was no significant difference change in corneal astigmatism in both groups. Evaluation of IL-6 levels in tears showed a significant difference between the control and treatment groups (P = 0.041). But no significant difference was observed between the Pilocarpine and the Tropicamide groups (P = 0.761). Evaluation of TNF-α level in tears also showed no significant difference between these groups (P = 0.088). Pilocarpine induced ciliary muscle contraction, which may cause pressure on the corneal limbus and scleral spur, resulting in changes in corneal curvature. But tropicamide eye drop did not affect corneal radius and other corneal parameters, and corneal topography can be carried out after the installation of tropicamide eye drop.


Assuntos
Astigmatismo , Tropicamida , Adulto , Astigmatismo/patologia , Córnea/patologia , Topografia da Córnea , Humanos , Interleucina-6/farmacologia , Soluções Oftálmicas/farmacologia , Pilocarpina/farmacologia , Estudos Prospectivos , Tropicamida/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
8.
Front Endocrinol (Lausanne) ; 13: 960265, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105397

RESUMO

Introduction: Salivary gland dysfunction (e.g., sialadenitis and xerostomia) is the most common complication of radioactive iodine (RAI) therapy for differentiated thyroid cancer (DTC). Several methods have been used to reduce/prevent this adverse effect. We aimed to systematically review the effectiveness of non-pharmacological and pharmacological interventions in preventing RAI-induced salivary gland dysfunction in patients with DTC. Methods: A systematic review was conducted, according to PRISMA guidelines. The protocol was registered (PROSPERO: CRD42022295229). PubMed, Embase, Scopus, and the Cochrane Library electronic databases were searched from inception to November 2021. Inclusion criteria were randomized controlled trials of DTC patients who were older than 18 years and underwent RAI after thyroidectomy in which at least one studied group received an intervention to prevent salivary gland dysfunction. Results: Twelve studies (a total of 667 participants) were included. Among DTC patients who were treated with RAI, nonpharmacological treatment such as parotid gland massage and aromatherapy ameliorated salivary gland dysfunction. Antioxidants such as vitamin E and selenium demonstrated radioprotective effects on the salivary gland, while other antioxidants did not show radioprotective benefits. Vitamin C showed no significant effects on preventing salivary gland dysfunction. Amifostine had inconsistent outcomes among studies. Among cholinergic agonists, pilocarpine did not demonstrate the radioprotective effect on parotid glands, while bethanechol lowered salivary gland dysfunction. However, the negative results from pilocarpine may be explained by the strong sialorrheic effect of the Cincinnati regimen in both study arms. Conclusion: Among non-pharmacological and pharmacological methods, parotid gland massage, aromatherapy, vitamin E, selenium, amifostine, and bethanechol may have benefits in minimizing RAI-induced salivary gland dysfunction in patients with DTC. The results are limited by a small number of patients and should be confirmed in future larger randomized controlled trials. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=295229, PROSPERO, identifier CRD42022295229.


Assuntos
Adenocarcinoma , Amifostina , Selênio , Neoplasias da Glândula Tireoide , Adenocarcinoma/tratamento farmacológico , Amifostina/farmacologia , Betanecol/farmacologia , Humanos , Radioisótopos do Iodo/efeitos adversos , Pilocarpina/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Glândulas Salivares , Neoplasias da Glândula Tireoide/radioterapia , Vitamina E/farmacologia
9.
J Oral Pathol Med ; 51(9): 801-809, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35996988

RESUMO

BACKGROUND: Radiation damage to salivary gland is inevitable in head and neck cancer patients receiving radiotherapy. Safe and effective treatments for protecting salivary glands from radiation are still unavailable. Mitochondrial damage is a critical mechanism in irradiated salivary gland; however, treatment targeting mitochondria has not received much attention. Nicotinamide is a key component of the mitochondrial metabolism. Here, we investigated the effects and underlying mechanisms of nicotinamide on protecting irradiated submandibular gland. METHODS: Submandibular gland cells and tissues were randomly divided into four groups: control, nicotinamide alone, radiation alone, and radiation with nicotinamide pretreatment. Cell viability was detected by PrestoBlue cell viability reagent. Histopathological alterations were observed with HE staining. Pilocarpine-stimulated saliva was measured from Wharton's duct. Cell apoptosis was determined by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Nicotinamide phosphoribosyl transferase was examined with immunofluorescence. The levels of nicotinamide adenine dinucleotide, mitochondrial membrane potential, and adenosine triphosphate were measured with the relevant kits. The mitochondrial ultrastructure was observed under transmission electron microscopy. RESULTS: Nicotinamide significantly mitigated radiation damage both in vitro and in vivo. Also, nicotinamide improved saliva secretion and reduced radiation-induced apoptosis in irradiated submandibular glands. Moreover, nicotinamide improved nicotinamide phosphoribosyl transferase and the levels of nicotinamide adenine dinucleotide/adenosine triphosphate and mitochondrial membrane potential, all of which were decreased by radiation in submandibular gland cells. Importantly, nicotinamide protected the mitochondrial ultrastructure from radiation. CONCLUSION: These findings demonstrate that nicotinamide alleviates radiation damage in submandibular gland by replenishing nicotinamide adenine dinucleotide and maintaining mitochondrial function and ultrastructure, suggesting that nicotinamide could be used as a prospective radioprotectant for preventing radiation sialadenitis.


Assuntos
Lesões por Radiação , Glândula Submandibular , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , DNA Nucleotidilexotransferase/metabolismo , DNA Nucleotidilexotransferase/farmacologia , Humanos , Mitocôndrias , NAD/metabolismo , NAD/farmacologia , Niacinamida/metabolismo , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Pilocarpina/farmacologia , Estudos Prospectivos , Lesões por Radiação/metabolismo , Lesões por Radiação/patologia , Ratos , Ratos Wistar , Glândula Submandibular/metabolismo
10.
Cell Biol Int ; 46(11): 1775-1786, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35989486

RESUMO

The present study was conducted to determine the effects of the γ-aminobutyric acid B (GABAB ) receptor positive allosteric modulator BHF177 on refractory epilepsy (RE). An RE rat model was initially established via treatment with lithium-pilocarpine. The RE rats were then treated with BHF177 or the GABAB receptor antagonist CGP46381, followed by recording of their seizure rate and assessment of their spatial learning in the Morris water maze test. Treatment of BHF177 reduced the seizure intensity, whereas this effect was revered upoj treatment with CGP46381. Immunohistochemistry revealed that BHF177 treatment diminished P-glycoprotein (P-gp) expression in the hippocampal tissues of RE rats. Next, we found that BHF177 activated GABAB receptor, resulting in upregulated expression of insulin receptor substrate 1 (IRS-1) and PI3K, as well as antiapoptotic factors (Bcl-2 and mTOR), along with suppression of the apoptosis factors Bax and cleaved caspase-3 in the hippocampal tissues. Further, activation of GABAB receptors by BHF177 alleviated the inflammatory response in hippocampal tissues of RE rats, as evidenced by reduced VCAM-1, ICAM-1, and tumor necrosis factor-α levels. Next, we treated primary cultured rat hippocampal neurons with BHF177 and the IRS-1 selective inhibitor NT157. BHF177 inhibited hippocampal apoptosis in rat hippocampal neurons by regulating the IRS-1/PI3K/Akt axis through crosstalk between GABAB and insulin-like growth factor-1 receptors. Collectively, our findings indicate that the BHF177 inhibited neuron apoptosis, thus protecting against RE through the IRS-1/PI3K/Akt axis, which may present a new therapeutic channel for RE.


Assuntos
Epilepsia Resistente a Medicamentos , Receptores de GABA-B , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Apoptose , Caspase 3/metabolismo , Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia Resistente a Medicamentos/patologia , Hipocampo/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Lítio/metabolismo , Lítio/farmacologia , Lítio/uso terapêutico , Neurônios/metabolismo , Norbornanos , Fosfatidilinositol 3-Quinases/metabolismo , Pilocarpina/metabolismo , Pilocarpina/farmacologia , Pilocarpina/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas , Ratos , Receptores de GABA-B/metabolismo , Receptores de GABA-B/uso terapêutico , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Convulsões/patologia , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/farmacologia , Molécula 1 de Adesão de Célula Vascular/uso terapêutico , Proteína X Associada a bcl-2/metabolismo , Ácido gama-Aminobutírico/farmacologia
11.
Prog Neurobiol ; 218: 102337, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35934131

RESUMO

Decreased expression of the δ subunit of the GABAA receptor (GABAAR) has been found in the dentate gyrus in several animal models of epilepsy and other disorders with increased excitability and is associated with altered modulation of tonic inhibition in dentate granule cells (GCs). In contrast, other GABAAR subunits, including α4 and γ2 subunits, are increased, but the relationship between these changes is unclear. The goals of this study were to determine if viral transfection of δ subunits in dentate GCs could increase δ subunit expression, alter expression of potentially-related GABAAR subunits, and restore more normal network excitability in the dentate gyrus in a mouse model of epilepsy. Pilocarpine-induced seizures were elicited in DOCK10-Cre mice that express Cre selectively in dentate GCs, and two weeks later the mice were injected unilaterally with a Cre-dependent δ-GABAAR viral vector. At 4-6 weeks following transfection, δ subunit immunolabeling was substantially increased in dentate GCs on the transfected side compared to the nontransfected side. Importantly, α4 and γ2 subunit labeling was downregulated on the transfected side. Electrophysiological studies revealed enhanced tonic inhibition, decreased network excitability, and increased neurosteroid sensitivity in slices from the δ subunit-transfected side compared to those from the nontransfected side of the same pilocarpine-treated animal, consistent with the formation of δ subunit-containing GABAARs. No differences were observed between sides of eYFP-transfected animals. These findings are consistent with the idea that altering expression of key subunits, such as the δ subunit, regulates GABAAR subunit assemblies, resulting in substantial effects on network excitability.


Assuntos
Epilepsia , Neuroesteroides , Animais , Giro Denteado/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Pilocarpina/metabolismo , Pilocarpina/farmacologia , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/metabolismo
12.
Sci Rep ; 12(1): 14690, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36038626

RESUMO

The molecular mechanisms underlying circuit re-wiring in the mature brain remains ill-defined. An eloquent example of adult circuit remodelling is the hippocampal mossy fiber (MF) sprouting found in diseases such as temporal lobe epilepsy. The molecular determinants underlying this retrograde re-wiring remain unclear. This may involve signaling system(s) controlling axon specification/growth during neurodevelopment reactivated during epileptogenesis. Since adenosine A2A receptors (A2AR) control axon formation/outgrowth and synapse stabilization during development, we now examined the contribution of A2AR to MF sprouting. A2AR blockade significantly attenuated status epilepticus(SE)-induced MF sprouting in a rat pilocarpine model. This involves A2AR located in dentate granule cells since their knockdown selectively in dentate granule cells reduced MF sprouting, most likely through the ability of A2AR to induce the formation/outgrowth of abnormal secondary axons found in rat hippocampal neurons. These A2AR should be activated by extracellular ATP-derived adenosine since a similar prevention/attenuation of SE-induced hippocampal MF sprouting was observed in CD73 knockout mice. These findings demonstrate that A2AR contribute to epilepsy-related MF sprouting, most likely through the reactivation of the ability of A2AR to control axon formation/outgrowth observed during neurodevelopment. These results frame the CD73-A2AR axis as a regulator of circuit remodeling in the mature brain.


Assuntos
Adenosina , Epilepsia do Lobo Temporal , Receptor A2A de Adenosina/metabolismo , Animais , Epilepsia do Lobo Temporal/induzido quimicamente , Camundongos , Fibras Musgosas Hipocampais , Pilocarpina/farmacologia , Ratos , Sinapses/fisiologia
13.
Pharmacol Rep ; 74(4): 602-613, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35871445

RESUMO

BACKGROUND: Non-deleterious episodes of seizure preconditioning can efficiently increase the brain's resistance to the consequent severe status epilepticus (SE). In the present investigation, we intended to elucidate further (i) the effects of preconditioning with pentylenetetrazole (PTZ) in the lithium-pilocarpine model of SE in male rats, along with (ii) the possible contribution of opioid, N-Methyl-D-aspartate (NMDA) receptors, and nitric oxide (NO) signaling transduction. METHODS: In male Wistar rats, the SE was incited by lithium administration (127 mg/kg, ip) 20 h before pilocarpine (60 mg/kg, ip). PTZ preconditioning was induced via a low-dose injection of PTZ (25 mg/kg) for 5 repeated days. To investigate the underlying signaling pathway, naltrexone (NTX; a non-specific opioid receptor antagonist), MK-801 (NMDA antagonist), L-NAME (a non-specific nitric oxide synthase (NOS) inhibitor), aminoguanidine (AG; a specific inducible NOS inhibitor), and 7-Nitroindazole (7-NI; a specific neuronal NOS inhibitor) were administered 15 min before PTZ injection. RESULTS: Preconditioning with PTZ successfully ameliorates the increased SE scores due to lithium-pilocarpine-induced SE (p < 0.05). None of the drugs given without PTZ preconditioning had an impact on SE outcomes. The observed anti-convulsant effect of PTZ preconditioning is reversed by the opioid receptor antagonists and NOS inhibitors. Conversely, the NMDA receptor antagonist enhanced the anti-convulsion activity caused by PTZ preconditioning. Quantifying nitrite level in the hippocampus showed a significant NO level decline in the PTZ-preconditioned animals. CONCLUSIONS: Therefore, PTZ preconditioning generates endogenous protection against SE, possibly through targeting opioid/NMDA receptors and NO signaling transduction in the animal model of lithium-pilocarpine-induced SE.


Assuntos
Pentilenotetrazol , Estado Epiléptico , Analgésicos Opioides/uso terapêutico , Animais , Anticonvulsivantes/uso terapêutico , Inibidores Enzimáticos/farmacologia , Lítio/uso terapêutico , Masculino , N-Metilaspartato , Óxido Nítrico/metabolismo , Pentilenotetrazol/toxicidade , Pilocarpina/farmacologia , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato , Receptores Opioides/metabolismo , Transdução de Sinais , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/prevenção & controle
14.
Pest Manag Sci ; 78(11): 4599-4607, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35841135

RESUMO

BACKGROUND: Pest management requires continual identification of new physiological targets and strategies to control pests affecting agriculture and public/animal health. We propose the muscarinic system as a target for agrochemicals because of its physiological importance. Unlike the muscarinic system, gamma-amino butyric acid (GABA) receptors are an established insecticide target. Here, we investigated target-site synergism using small molecule probes (agonist and antagonist) against the muscarinic system and their ability to enhance the toxicity of GABAergic insecticides in Drosophila melanogaster (Meigen). RESULTS: Oral delivery of pilocarpine (muscarinic agonist) enhanced the toxicity of dieldrin, fipronil, and lindane, resulting in synergist ratios (SRs) between 4-32-fold (orally delivered) or between 2-67-fold when insecticides were topically applied. The synergism between pilocarpine and the GABA-insecticides was greater than the synergism observed with atropine (muscarinic antagonist), and was greater, or comparable, to the synergism observed with the metabolic inhibitor piperonyl butoxide. In addition to lethality, pilocarpine increased the knockdown of lindane. The mechanism of synergism was also investigated in the central nervous system using extracellular electrophysiology, where pilocarpine (3 µmo/L) lowered the half-maximal inhibitory concentration (IC50 ) of lindane from 1.3 (0.86-1.98) µmol/L to 0.17 (0.14-0.21) µmol/L and fipronil's IC50 from 2.2 (1.54-3.29) µmol/L to 0.56 (0.40-0.77) µmol/L. CONCLUSION: Convergence of the cellular function between the muscarinic and GABAergic systems enhanced the insecticidal activity of GABA receptor blocking insecticides through the modulation of the central nervous system (CNS). The future impact of the findings could be the reduction of the active ingredient needed in a formulation with the development of muscarinic synergists. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Inseticidas , Animais , Derivados da Atropina/metabolismo , Canais de Cloreto/metabolismo , Dieldrin/metabolismo , Dieldrin/farmacologia , Drosophila melanogaster , Hexaclorocicloexano/metabolismo , Inseticidas/metabolismo , Inseticidas/farmacologia , Agonistas Muscarínicos/metabolismo , Agonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/farmacologia , Pilocarpina/metabolismo , Pilocarpina/farmacologia , Butóxido de Piperonila , Receptores de GABA/genética , Receptores de GABA/metabolismo , Receptores Muscarínicos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologia
15.
Neurosci Lett ; 786: 136774, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35809878

RESUMO

Opioid use disorder mainly results from functional defects in the brain reward loop, which includs the ventral tegmental area (VTA) and nucleus accumbens (NAc; consisting of shell and core, NAcS and NAcC). Reward effects contribute to opioid use disorder. RMTg M3 receptors play a role in opioid reward by regulating the γ-aminobutyric acid (GABA) neuron activity. Dopamine D1 receptors expressed on GABA neurons regulate opioid reward by mediating the dopamine neuron activity in the VTA. Therefore, we investigated the effect of activating M3 receptors by microinjecting pilocarpine into the RMTg along with activating D1 receptors by microinjecting SKF38393 into the VTA on morphine-induced reward effect, using the conditioned place preference (CPP) paradigm (locomotion was also recorded). We also investigated whether the activation of M3 receptors in the RMTg influenced dopamine release in the NAcS. The results showed that the inhibitory role of RMTg pilocarpine (60 µg/rat) infusions in morphine-induced CPP was reversed by VTA SKF38393 (4 µg/rat) infusions. Moreover, morphine (5 mg/kg, i.p.) increased dopamine release in the NAcS, which was blunted by microinjecting pilocarpine (60 µg/rat) into the RMTg. These results indicate that RMTg M3 receptors mediate morphine-induced reward effect, which is probably related to the dopamine activity within the VTA and NAcS. The relationship between RMTg M3 receptors and the mesolimbic dopamine system could be a potential direction for the treatment of opioid use disorder, but further verification through more comprehensive techniques is needed.


Assuntos
Morfina , Transtornos Relacionados ao Uso de Opioides , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Analgésicos Opioides/farmacologia , Animais , Encéfalo , Colinérgicos/farmacologia , Dopamina/farmacologia , Neurônios Dopaminérgicos , Morfina/farmacologia , Núcleo Accumbens , Pilocarpina/farmacologia , Ratos , Receptores Muscarínicos , Recompensa , Área Tegmentar Ventral
16.
Neurosci Lett ; 782: 136690, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35598692

RESUMO

Our study aimed to determine the effects of pilocarpine and the mechanisms involving muscarinic acetylcholine receptors (mAChRs) on glycine receptors (GlyRs) in neurons of the spinal cord ventral horn. An enzymatic digestion combined with acute mechanical separation was applied to isolate neurons from the spinal cord ventral horn. Patch-clamp recording was then used to investigate the outcomes of pilocarpine. Our results indicate that pilocarpine increased the glycine currents in a concentration-dependent manner, which was blocked by the M3-AChR selective antagonists 4-DAMP and J104129. Pilocarpine also enhanced the glycine currents in nominally Ca2+-free extracellular solution. Conversely, the enhancement of glycine currents by pilocarpine disappeared when intracellular Ca2+ was chelated by BAPTA. Heparin and Xe-C, which are IP3 receptor antagonists, also totally abolished the pilocarpine effect. Furthermore, Bis-IV, a PKC inhibitor, eliminated the pilocarpine effect. Additionally, PMA, a PKC activator, mimicked the pilocarpine effect. These results indicate that pilocarpine may increase the glycine currents by activating the M3-AChRs and IP3/Ca2+/PKC pathways.


Assuntos
Células do Corno Anterior , Glicina , Células do Corno Anterior/metabolismo , Glicina/metabolismo , Glicina/farmacologia , Pilocarpina/farmacologia , Transdução de Sinais , Medula Espinal/metabolismo
17.
Biol Pharm Bull ; 45(4): 403-408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370264

RESUMO

Sjogren's syndrome and radiation therapy for head and neck cancers are often accompanied by xerostomia. Oral pilocarpine (PCP) to treat xerostomia produces systemic side effects, such as runny nose and lacrimation. To improve the therapeutic efficacy of PCP and reduce the aforementioned side effects, we developed a topical delivery system for PCP using freeze-dried sheets of hyaluronic acid (HA). The advantages of HA sheets over conventional oral formulations were examined through in vivo pharmacokinetic and pharmacodynamic studies after their application to oral tissues and salivary glands. The concentration of PCP in the submucosal tissue of the oral cavity was determined using the microdialysis (MD) method after buccal application of HA sheets containing PCP to hamsters. The concentration of PCP in the MD outflow was quite low after gastric administration, whereas the PCP concentration in plasma was high. In contrast, after buccal application of HA sheets containing PCP, the concentration of the drug in the MD outflow increased, despite the negligible concentration in plasma. These findings indicated that both enhancement of saliva secretion and the avoidance of systemic side effects could be achieved through buccal administration of PCP-loaded HA sheets. In addition, the pharmacodynamic study showed that when compared with intravenous and gastric administration, salivary application of HA sheets containing PCP resulted in similar volumes of saliva secretion and reduced lacrimal secretions. In conclusion, freeze-dried HA sheets allow for the development of a novel buccal delivery system with enhanced therapeutic efficacy and safety to treat xerostomia.


Assuntos
Neoplasias de Cabeça e Pescoço , Xerostomia , Neoplasias de Cabeça e Pescoço/induzido quimicamente , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Pilocarpina/farmacologia , Pilocarpina/uso terapêutico , Glândulas Salivares/efeitos da radiação , Salivação/efeitos da radiação , Xerostomia/induzido quimicamente , Xerostomia/tratamento farmacológico
18.
Exp Physiol ; 107(5): 441-449, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35340063

RESUMO

NEW FINDINGS: What is the central question of this study? Does inhibition of K+ channels modulate the exercise-training-induced augmentation in cholinergic and thermal sweating? What is the main finding and its importance? Iontophoretic administration of tetraethylammonium, a K+ channel blocker, blunted sweating induced by a low dose (0.001%) of the cholinergic agent pilocarpine, but not heat-induced sweating. However, no differences in the cholinergic sweating were observed between young endurance-trained and untrained men. Thus, while K+ channels play a role in the regulation of eccrine sweating, they do not contribute to the increase in sweating commonly observed in endurance-trained adults. Our findings provide important new insights into the mechanisms underlying the regulation of sweating by endurance conditioning. ABSTRACT: We evaluated the hypothesis that the activation of K+ channels mediates the exercise-training-induced augmentation of cholinergic and thermal sweating. On separate days, 11 endurance-trained and 10 untrained men participated in two experimental protocols. Prior to each protocol, we administered 2% tetraethylammonium (TEA, K+ channels blocker) and saline (Control) at forearm skin sites on both arms via transdermal iontophoresis. In protocol 1, low (0.001%) and high (1%) doses of pilocarpine were administered at the TEA-treated and Control sites over a 60-min period. In protocol 2, participants were passively heated by immersing their lower limbs in hot water (43°C) until core (rectal) temperature (Tc ) increased by 0.8°C above resting levels. Administration of TEA attenuated cholinergic sweating (P = 0.001) during the initial 20 min after the treatment of low dose of pilocarpine only whilst the response was similar between the groups (P = 0.163). Cholinergic and thermal sweating were higher in the trained relative to the untrained men (all P ≤ 0.033). Thermal sweating reached ∼90% of the response at a Tc elevation of 0.8°C during the initial 20 min of passive heating, which corresponds to the period wherein TEA attenuated cholinergic sweating in protocol 1. However, sweating did not differ between the Control and TEA sites in either group (P = 0.704). We showed that activation of K+ channels does not appear to mediate the elevated sweating response induced by a low dose of pilocarpine in trained men. We also demonstrated that K+ channels do not contribute to sweating during heat stress in either group.


Assuntos
Treino Aeróbico , Sudorese , Adulto , Colinérgicos , Humanos , Masculino , Pilocarpina/farmacologia , Tetraetilamônio/farmacologia
19.
Epilepsy Behav ; 130: 108649, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344809

RESUMO

BACKGROUND: Status epilepticus (SE) is a continuous episode of seizures which leads to hippocampal neurodegeneration, severe systemic inflammation, and extreme damage to the brain. Modafinil, a psychostimulant and wake-promoting agent, has exerted neuroprotective and anti-inflammatory effects in previous preclinical studies. The aim of this study was to assess effects of modafinil on the lithium-pilocarpine-induced SE rat model and to explore possible involvement of tumor necrosis factor-α (TNF-α) and nitric oxide (NO) pathways in this regard. METHODS: Status epilepticus was provoked by injection of lithium chloride (127 mg/kg, intraperitoneally [i.p]) and pilocarpine (60 mg/kg, i.p.) in rats. Animals received different modafinil doses (50, 75, 100, and 150 mg/kg, i.p.) and SE scores were documented over 3 hours of duration. Moreover, the role of the nitrergic pathway in the effects of modafinil was evaluated by injection of the non-selective NO synthase (NOS) inhibitor L-NG-Nitro arginine methyl ester (L-NAME, 10 mg/kg, i.p.), the selective neuronal NOS inhibitor 7-nitroindazole (30 mg/kg, i.p.), and the selective inducible NOS inhibitor aminoguanidine (100 mg/kg, i.p.) 15 min before saline/vehicle or modafinil. The ELISA method was used to quantify TNF-α and NO metabolite levels in the isolated hippocampus. RESULTS: Modafinil at 100 mg/kg significantly decreased SE scores (P < 0.01). Pre-treatment with L-NAME, 7-nitroindazole, and aminoguanidine significantly reversed the anticonvulsive effects of modafinil. Status epilepticus-induced animals showed significantly higher NO metabolite and TNF-α levels in their hippocampal tissues, an effect that was reversed by modafinil (100 mg/kg, i.p.) treatment. Administration of NOS inhibitors resulted in excessive NO level reduction but an escalation of TNF-α level in modafinil-treated SE-animals. CONCLUSION: Our study revealed anticonvulsive effects of modafinil in the lithium-pilocarpine-induced SE rat model via possible involvement of TNF-α and nitrergic pathways.


Assuntos
Pilocarpina , Estado Epiléptico , Animais , Humanos , Lítio/efeitos adversos , Modafinila/efeitos adversos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Pilocarpina/farmacologia , Ratos , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/patologia , Fator de Necrose Tumoral alfa
20.
Bioengineered ; 13(4): 8689-8698, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35322725

RESUMO

Hederagenin (HE) plays a protective role by inhibiting cell proliferation and ameliorating fibrosis. The current therapy for Chronic kidney disease (CKD) often result in the risks of side effects. The present study aimed to explore whether it can protect against renal fibrosis and unveil the underlying mechanism. Transforming growth factor (TGF)-ß was used to induce the fibroblasts NRK-49 F for the simulation of renal fibrosis. The cell viability and expression of fibrosis-related proteins in TGF-ß-treated NRK-49 F cells was, respectively, measured by Cell Counting Kit-8 (CCK-8) and western blot. After predicting the target genes of HE, M3 receptor was measured in NRK-49 F cells treated with TGF-ß alone or in combination with HE. Then, M3 receptor was silenced in TGF-ß-treated NRK-49 F cells for the detection of its role in proliferation and fibrosis. Muscarinic acetylcholine receptor M3 (M3 receptor) agonist pilocarpine was further added to determine the role of M3 receptor involved. HE inhibited the proliferation and fibrosis of TGF-ß-treated NRK-49 F cells. M3 receptor was predicted to be a target of HE. Moreover, interference of M3 receptor improved the proliferation and fibrosis of TGF-ß-treated NRK-49 F cells. Further addition of pilocarpine reversed the inhibitory effect of HE on proliferation and fibrosis of TGF-ß-treated NRK-49 F cells. HE protects against renal fibrosis in NRK-49 F cells by targeting Muscarinic acetylcholine receptor, which will provide theoretical basis for the clinical use of HE for kidney-related disease treatment.


Assuntos
Nefropatias , Ácido Oleanólico , Linhagem Celular , Fibrose , Humanos , Rim , Nefropatias/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , Pilocarpina/farmacologia , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Fator de Crescimento Transformador beta/farmacologia
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