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1.
Proc Natl Acad Sci U S A ; 120(12): e2213093120, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36920928

RESUMEN

Dopamine (DA) loss in Parkinson's disease (PD) causes debilitating motor deficits. However, dopamine is also widely linked to reward prediction and learning, and the contribution of dopamine-dependent learning to movements that are impaired in PD-which often do not lead to explicit rewards-is unclear. Here, we used two distinct motor tasks to dissociate dopamine's acute motoric effects vs. its long-lasting, learning-mediated effects. In dopamine-depleted mice, motor task performance gradually worsened with task exposure. Task experience was critical, as mice that remained in the home cage during the same period were relatively unimpaired when subsequently probed on the task. Repeated dopamine replacement treatments acutely rescued deficits and gradually induced long-term rescue that persisted despite treatment withdrawal. Surprisingly, both long-term rescue and parkinsonian performance decline were task specific, implicating dopamine-dependent learning. D1R activation potently induced acute rescue that gradually consolidated into long-term rescue. Conversely, reduced D2R activation potently induced parkinsonian decline. In dopamine-depleted mice, either D1R activation or D2R activation prevented parkinsonian decline, and both restored balanced activation of direct vs. indirect striatal pathways. These findings suggest that reinforcement and maintenance of movements-even movements not leading to explicit rewards-are fundamental functions of dopamine and provide potential mechanisms for the hitherto unexplained "long-duration response" by dopaminergic therapies in PD.


Asunto(s)
Dopamina , Enfermedad de Parkinson , Ratones , Animales , Dopamina/metabolismo , Neuronas/metabolismo , Cuerpo Estriado/metabolismo , Aprendizaje/fisiología , Enfermedad de Parkinson/metabolismo
2.
Molecules ; 29(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38474465

RESUMEN

The pharmacological activity and medicinal significance of Amauroderma rugosum (AR) have rarely been documented. We examined the antioxidant and neuroprotective effects of AR on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in an SH-SY5Y human neuroblastoma cell model of Parkinson's disease (PD) and explored the active ingredients responsible for these effects. The results showed that the AR aqueous extract could scavenge reactive oxygen species and reduce SH-SY5Y cell death induced by 6-OHDA. In addition, the AR aqueous extract increased the survival of Caenorhabditis elegans upon juglone-induced toxicity. Among the constituents of AR, only polysaccharides and gallic acid exhibited antioxidant and neuroprotective effects. The AR aqueous extract reduced apoptosis and increased the expression of phospho-Akt, phospho-mTOR, phospho-MEK, phospho-ERK, and superoxide dismutase-1 in 6-OHDA-treated SH-SY5Y cells. The polysaccharide-rich AR extract was slightly more potent than the aqueous AR extract; however, it did not affect the expression of phospho-Akt or phospho-mTOR. In conclusion, the AR aqueous extract possessed antioxidant and neuroprotective properties against 6-OHDA-induced toxicity in SH-SY5Y cells. The mechanism of action involves the upregulation of the Akt/mTOR and MEK/ERK-dependent pathways. These findings indicate the potential utility of AR and its active ingredients in preventing or treating neurodegenerative disorders associated with oxidative stress such as PD.


Asunto(s)
Neuroblastoma , Fármacos Neuroprotectores , Enfermedad de Parkinson , Polyporaceae , Humanos , Oxidopamina/farmacología , Fármacos Neuroprotectores/farmacología , Antioxidantes/farmacología , Ácido Gálico/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Línea Celular Tumoral , Neuroblastoma/tratamiento farmacológico , Apoptosis , Especies Reactivas de Oxígeno/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Serina-Treonina Quinasas TOR , Quinasas de Proteína Quinasa Activadas por Mitógenos
3.
J Foot Ankle Surg ; 63(2): 140-144, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37806484

RESUMEN

Hammertoes with greater preoperative transverse plane deformity are more likely to recur after corrective surgery; however, it is unclear whether this represents an inherent (fixed, nonmodifiable) risk, or whether steps can be taken intraoperatively to mitigate this risk. In this study, we examined whether transverse plane transposition and/or shortening of the second metatarsal during second hammertoe surgery influenced recurrence. We performed a secondary analysis of pre-existing data from patients that had previously undergone second hammertoe surgery at our institution between January 1, 2011 and December 31, 2013. One hundred two patients (137 toes) were followed for a mean 28 ± 7.8 months postoperatively. Thirty-seven toes required, at the surgeon's discretion, an additional/concomitant Weil metatarsal osteotomy. Magnitude of transverse plane transposition and shortening of the second metatarsal, and joint angular measurements were obtained from the second metatarsophalangeal joint on weightbearing AP radiographs preoperatively and at 6 to 10 weeks postoperatively. Cox regression analysis was used to identify predictors of hammertoe recurrence using these new variables and a set of known predictors. In the final regression model, failure to establish a satisfactory postoperative metatarsal parabola (i.e., long second metatarsal; Nilsonne values <-4 mm, multivariate hazards ratio [HR] 1.96, p = .097), and intraoperative lateral transposition of the metatarsal head (multivariate HR 3.45, p = .028) seemed to confer additional risk for hammertoe recurrence. We conclude that shortening osteotomies may be assistive in some individuals, while further inquiry is still needed to determine whether similar benefits can be derived from medial head transposition in medial toe deformities.


Asunto(s)
Deformidades del Pie , Síndrome del Dedo del Pie en Martillo , Huesos Metatarsianos , Articulación Metatarsofalángica , Humanos , Huesos Metatarsianos/diagnóstico por imagen , Huesos Metatarsianos/cirugía , Articulación Metatarsofalángica/diagnóstico por imagen , Articulación Metatarsofalángica/cirugía , Síndrome del Dedo del Pie en Martillo/diagnóstico por imagen , Síndrome del Dedo del Pie en Martillo/cirugía , Osteotomía , Estudios Retrospectivos
4.
PLoS Genet ; 16(6): e1008829, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32502151

RESUMEN

Ion channels are present at specific levels within subcellular compartments of excitable cells. The regulation of ion channel trafficking and targeting is an effective way to control cell excitability. The BK channel is a calcium-activated potassium channel that serves as a negative feedback mechanism at presynaptic axon terminals and sites of muscle excitation. The C. elegans BK channel ortholog, SLO-1, requires an endoplasmic reticulum (ER) membrane protein for efficient anterograde transport to these locations. Here, we found that, in the absence of this ER membrane protein, SLO-1 channels that are seemingly normally folded and expressed at physiological levels undergo SEL-11/HRD1-mediated ER-associated degradation (ERAD). This SLO-1 degradation is also indirectly regulated by a SKN-1A/NRF1-mediated transcriptional mechanism that controls proteasome levels. Therefore, our data indicate that SLO-1 channel density is regulated by the competitive balance between the efficiency of ER trafficking machinery and the capacity of ERAD.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiología , Proteínas de Unión al ADN/metabolismo , Degradación Asociada con el Retículo Endoplásmico/genética , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Terminales Presinápticos/metabolismo , Factores de Transcripción/metabolismo , Aldicarb/farmacología , Animales , Animales Modificados Genéticamente , Caenorhabditis elegans/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Acoplamiento Excitación-Contracción/efectos de los fármacos , Acoplamiento Excitación-Contracción/genética , Retroalimentación Fisiológica/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Músculos/inervación , Terminales Presinápticos/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal , Isoformas de Proteínas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
5.
Molecules ; 27(19)2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36235070

RESUMEN

Keratinocytes form the physical barrier of the skin and play an important role in the inflammatory process. Amauroderma rugosum is an edible mushroom; however, its pharmacological properties have seldom been studied. Although the anti-inflammatory effect of the organic solvent extract of Amauroderma rugosum has been previously reported, it is not known whether the aqueous extract has a similar effect. In addition, the effect of Amauorderma rugosum extract on skin has never been explored. Therefore, the objectives of the present study were to evaluate the anti-inflammatory effects of the aqueous extract of Amauroderma rugosum on HaCaT keratinocytes, to explore its mechanisms of action, and to study the possible active ingredients involved. The results showed that the aqueous extract of Amauroderm rugosum at a concentration of 1.5 mg/mL was non-toxic to HaCaT cells and inhibited the release of cytokine interleukin-1ß, and chemokines interleukin-8 and monocyte chemoattractant protein-1 in tumor necrosis factor (TNF)-α- and interferon (IFN)-γ-stimulated HaCaT cells. Amauroderma rugosum extract reduced the intracellular levels of reactive oxygen species. In addition, Amauroderma rugosum extract reduced the total protein expression of nuclear factor-kappa B (NF-κB) and B-cells inhibitor alpha in HaCaT keratinocytes and inhibited the phosphorylation of mitogen-activated protein kinase kinase (MEK) 1/2, extracellular signal-regulated kinase (ERK) 1/2, protein kinase B (Akt), and mammalian target of rapamycin (mTOR) in TNF-α- and INF-γ-stimulated HaCaT keratinocytes. Chemical analysis revealed that the aqueous extract of Amauroderma rugosum contains polysaccharides, triterpenes, and phenolic compounds. Anti-inflammatory compounds, such as gallic acid, guanosine, and uridine, were also present. The anti-inflammatory effect of Amauroderma rugosum could be mimicked by a combination of gallic acid, guanosine, and uridine. In conclusion, our study suggests that the aqueous extract of Amauroderma rugosum exerts anti-inflammatory effects on keratinocytes through its antioxidant and inhibitory effects on MEK/ERK-, Akt/mTOR-, and NF-κB-dependent signaling pathways.


Asunto(s)
Triterpenos , Factor de Necrosis Tumoral alfa , Antiinflamatorios/metabolismo , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Quimiocina CCL2/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ácido Gálico/farmacología , Guanosina/metabolismo , Interferón gamma/metabolismo , Interferón gamma/farmacología , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Queratinocitos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Polyporaceae , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Solventes/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Triterpenos/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Uridina/farmacología
6.
Intern Med J ; 48(7): 864-868, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29984505

RESUMEN

Accurate chest X-ray (CXR) interpretation is an essential skill in clinical practice. Previous studies have shown poor accuracy and confidence rates (CR) of CXR interpretation by junior doctors and medical students. We presented 10 chest radiographs via an online questionnaire to Australian medical students and junior doctors, who were asked to identify the radiographic abnormality from a list of 15 options and to rate their confidence for each answer. Of 67 complete responses, junior doctors achieved a mean score of 57.6% and medical students 56.1%, with CR of 67 versus 58% respectively. There was a significant positive relationship between accuracy and CR among junior doctors (Pearson's coefficient + 0.798, P = 0.006) and students (Pearson's coefficient + 0.716, P = 0.020). This study identified similarities in strength and weakness in CXR interpretation between medical students and junior doctors. There was a positive association between test scores and self-rated confidence scores.


Asunto(s)
Competencia Clínica , Cuerpo Médico de Hospitales , Radiografía Torácica/normas , Estudiantes de Medicina , Australia , Humanos , Encuestas y Cuestionarios
7.
Proc Natl Acad Sci U S A ; 111(10): 3793-8, 2014 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-24567377

RESUMEN

Toll-like receptors (TLRs) play key roles in innate immune recognition of pathogen-associated molecular patterns of invading microbes. Among the 10 TLR family members identified in humans, TLR10 remains an orphan receptor without known agonist or function. TLR10 is a pseudogene in mice and mouse models are noninformative in this regard. Using influenza virus infection in primary human peripheral blood monocyte-derived macrophages and a human monocytic cell line, we now provide previously unidentified evidence that TLR10 plays a role in innate immune responses following viral infection. Influenza virus infection increased TLR10 expression and TLR10 contributed to innate immune sensing of viral infection leading to cytokine induction, including proinflammatory cytokines and interferons. TLR10 induction is more pronounced following infection with highly pathogenic avian influenza H5N1 virus compared with a low pathogenic H1N1 virus. Induction of TLR10 by virus infection requires active virus replication and de novo protein synthesis. Culture supernatants of virus-infected cells modestly up-regulate TLR10 expression in nonvirus-infected cells. Signaling via TLR10 was activated by the functional RNA-protein complex of influenza virus leading to robust induction of cytokine expression. Taken together, our findings identify TLR10 as an important innate immune sensor of viral infection and its role in innate immune defense and immunopathology following viral and bacterial pathogens deserves attention.


Asunto(s)
Inmunidad Innata/inmunología , Subtipo H5N1 del Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Receptor Toll-Like 10/inmunología , Animales , Benzotiazoles , Western Blotting , Cartilla de ADN/genética , Diaminas , Perros , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Humanos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Macrófagos , Células de Riñón Canino Madin Darby , Ratones , Compuestos Orgánicos , Quinolinas , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 10/metabolismo
8.
Immunol Rev ; 244(1): 169-87, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22017438

RESUMEN

The tumor necrosis factor (TNF) receptor superfamily member herpesvirus entry mediator (HVEM) (TNFRSF14) regulates T-cell immune responses by activating both inflammatory and inhibitory signaling pathways. HVEM acts as both a receptor for the canonical TNF-related ligands, LIGHT [lymphotoxin-like, exhibits inducible expression, and competes with herpes simplex virus glycoprotein D for HVEM, a receptor expressed on T lymphocytes] and lymphotoxin-α, and as a ligand for the immunoglobulin superfamily proteins BTLA (B and T lymphocyte attenuator) and CD160, a feature distinguishing HVEM from other immune regulatory molecules. The ability of HVEM to interact with multiple ligands in distinct configurations creates a functionally diverse set of intrinsic and bidirectional signaling pathways that control both inflammatory and inhibitory responses. The HVEM system is integrated into the larger LTßR and TNFR network through extensive shared ligand and receptor usage. Experimental mouse models and human diseases indicate that dysregulation of HVEM network may contribute to autoimmune pathogenesis, making it an attractive target for drug intervention.


Asunto(s)
Herpes Simple/inmunología , Herpesvirus Humano 1/inmunología , Inmunidad Innata , Linfotoxina-alfa/inmunología , Miembro 14 de Receptores del Factor de Necrosis Tumoral , Transducción de Señal/inmunología , Linfocitos T/inmunología , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/inmunología , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos CD/metabolismo , Autoinmunidad , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/inmunología , Proteínas Ligadas a GPI/metabolismo , Expresión Génica/inmunología , Herpes Simple/metabolismo , Herpes Simple/virología , Humanos , Activación de Linfocitos , Receptor beta de Linfotoxina/genética , Receptor beta de Linfotoxina/inmunología , Receptor beta de Linfotoxina/metabolismo , Linfotoxina-alfa/genética , Linfotoxina-alfa/metabolismo , Ratones , Ratones Noqueados , Unión Proteica/inmunología , Receptor Cross-Talk/inmunología , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , Receptores Inmunológicos/metabolismo , Miembro 14 de Receptores del Factor de Necrosis Tumoral/genética , Miembro 14 de Receptores del Factor de Necrosis Tumoral/inmunología , Miembro 14 de Receptores del Factor de Necrosis Tumoral/metabolismo , Linfocitos T/metabolismo , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/metabolismo
9.
Artículo en Inglés | MEDLINE | ID: mdl-39240772

RESUMEN

Charcot's neuroarthropathy complicated by calcaneal osteomyelitis can be difficult to treat. Various surgical techniques describe how to manage these conditions. Eggshell-type debridement with application of antibiotic-impregnated bone substitute is a viable option that eliminates infected bone and allows staged reconstructive surgery. A 50-year-old woman with right midfoot Charcot's neuroarthropathy presented with osteomyelitis of the cuboid and fourth and fifth metatarsal bases after resection and failed antibiotic therapy. The patient eventually developed adductovarus, septic shock, and hematogenous osteomyelitis of the calcaneus, navicular, and lateral cuneiform. Vacuum-assisted eggshell-type debridement was performed, and the calcaneal defect was filled with antibiotic-impregnated calcium sulfate and calcium phosphate. Eight weeks after the initial surgery, the infection resolved; however, the patient had trouble walking. She underwent staged Charcot's reconstructive surgery with application of a dynamic multiplanar external fixator with gradual deformity and split-thickness skin graft to cover the residual plantar lateral foot wound. The second stage included septic fusion of the midfoot and subtalar joint from the frame. Twelve weeks postoperatively, radiographic union was achieved, the external fixator was removed, and the patient demonstrated a plantigrade foot. She was transitioned to a total-contact cast and allowed to bear weight as tolerated. Eighteen months after the initial procedure, the patient is wound-free and weightbearing in a CROW boot. This innovative eggshell-type debridement technique aspirates osteomyelitic cancellous bone while preserving cortical bone. It can be particularly useful in hematogenous osteomyelitis, where cortical integrity is not breached, or in situations where there is minimal cortical involvement. Specifically preserving the calcaneus, a major weightbearing bone, permits subsequent reconstructive surgical planning. At 18 months, there were no signs of osteomyelitis recurrence.


Asunto(s)
Antibacterianos , Sustitutos de Huesos , Calcáneo , Desbridamiento , Osteomielitis , Humanos , Femenino , Persona de Mediana Edad , Osteomielitis/cirugía , Osteomielitis/etiología , Calcáneo/cirugía , Desbridamiento/métodos , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Sustitutos de Huesos/uso terapéutico , Artropatía Neurógena/cirugía , Sulfato de Calcio/uso terapéutico , Procedimientos de Cirugía Plástica/métodos , Terapia de Presión Negativa para Heridas/métodos
10.
Artículo en Inglés | MEDLINE | ID: mdl-38758692

RESUMEN

BACKGROUND: Bone and periarticular tissue discoloration can be an unexpected finding that is often disconcerting for surgeons and may alter surgical plans and overall patient management. Common causes of bone discoloration include infection, avascular necrosis, and bone inflammation. Minocycline-induced black bone disease is a rare and relatively benign abnormality encountered in foot and ankle surgery that can cause significant black, blue, and gray discoloration of bone. METHODS: Unanticipated intraoperative findings of diffuse black, blue, and gray bone discoloration during an elective forefoot operation raised concern for a metabolically malignant process and prompted the conversion of plans for a first metatarsophalangeal joint implant arthroplasty to a Keller arthroplasty. The plan for proximal interphalangeal joint arthroplasties of the lesser digits were continued as planned. Bone specimens were sent for pathologic analysis. RESULTS: Postoperative analysis identified chronic use of a minocycline for acne vulgaris. Pathologic analysis of the specimens ruled out malignant processes. Altogether, the data available led to the diagnosis of minocycline-induced black bone disease. Since the last follow-up, the patient has healed well without complications. CONCLUSIONS: Our case report underscores the importance of including the chronic use of tetracyclines in medical history intake during preoperative visits to assist the surgeon in intraoperative decision-making.


Asunto(s)
Antibacterianos , Minociclina , Humanos , Acné Vulgar/tratamiento farmacológico , Antibacterianos/efectos adversos , Enfermedades Óseas/inducido químicamente , Minociclina/efectos adversos
11.
J Pharmacol Exp Ther ; 347(2): 410-23, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24018640

RESUMEN

Dopamine D3 receptor (D3R)-selective compounds may be useful medications for cocaine dependence. In this study, we identified two novel arylamide phenylpiperazines, OS-3-106 and WW-III-55, as partial agonists at the D3R in the adenylyl cyclase inhibition assay. OS-3-106 and WW-III-55 have 115- and 862-fold D3R:D2 receptor (D2R) binding selectivity, respectively. We investigated their effects (0, 3, 5.6, or 10 mg/kg) on operant responding by using a multiple variable-interval (VI) 60-second schedule that alternated components with sucrose reinforcement and components with intravenous cocaine reinforcement (0.375 mg/kg). Additionally, we evaluated the effect of OS-3-106 (10 mg/kg) on the dose-response function of cocaine self-administration and the effect of WW-III-55 (0-5.6 mg/kg) on a progressive ratio schedule with either cocaine or sucrose reinforcement. Both compounds were also examined for effects on locomotion and yawning induced by a D3R agonist. OS-3-106 decreased cocaine and sucrose reinforcement rates, increased latency to first response for cocaine but not sucrose, and downshifted the cocaine self-administration dose-response function. WW-III-55 did not affect cocaine self-administration on the multiple-variable interval schedule, but it reduced cocaine and sucrose intake on the progressive ratio schedule. Both compounds reduced locomotion at doses that reduced responding, and both compounds attenuated yawning induced by low doses of 7-OH-DPAT (a D3R-mediated behavior), but neither affected yawning on the descending limb of the 7-OH-DPAT dose-response function (a D2R-mediated behavior). Therefore, both compounds blocked a D3R-mediated behavior. However, OS-3-106 was more effective in reducing cocaine self-administration. These findings support D3Rs, and possibly D2Rs, as targets for medications aimed at reducing the motivation to seek cocaine.


Asunto(s)
Benzamidas/uso terapéutico , Trastornos Relacionados con Cocaína/tratamiento farmacológico , Cocaína/administración & dosificación , Agonistas de Dopamina/uso terapéutico , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Piperazinas/uso terapéutico , Receptores de Dopamina D3/agonistas , Animales , Benzamidas/administración & dosificación , Benzamidas/química , Cocaína/efectos adversos , Trastornos Relacionados con Cocaína/metabolismo , Trastornos Relacionados con Cocaína/psicología , Agonistas de Dopamina/administración & dosificación , Agonistas de Dopamina/química , Agonismo Parcial de Drogas , Células HEK293 , Humanos , Masculino , Estructura Molecular , Piperazinas/administración & dosificación , Piperazinas/química , Ratas , Ratas Sprague-Dawley , Refuerzo en Psicología , Autoadministración
12.
Synapse ; 67(12): 847-55, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23766142

RESUMEN

WC 44 and WC 10 are phenylpiperazines with low (23 fold) to moderate (42 fold) selectivity for dopamine D3 receptors (D3Rs) over D2Rs, respectively. WC 44 is a full D3R agonist in the forskolin-stimulated adenylyl cyclase (AC) assay, whereas WC 10 has little efficacy. In contrast to their opposite effects in the AC assay, these drugs often produce similar behavioral effects, suggesting that the AC assay does not predict the efficacy of these drugs in vivo. Here, we examined whether Fos protein expression induced by these drugs would be more consistent with their behavioral effects in vivo. Rats received either vehicle, WC 10 (5.6 mg/kg, i.p.), WC 44 (10.0 mg/kg, i.p), cocaine (10.0 mg/kg, i.p.), or cocaine with WC 10 (5.6 mg/kg, i.p.) or with WC 44 (10.0 mg/kg, i.p). Locomotion was monitored for 90 min and the brains were harvested for immunohistochemistry. Both WC 10 and WC 44 decreased spontaneous and cocaine-induced locomotion. Both compounds also increased Fos expression relative to saline in the dorsal striatum and nucleus accumbens core and shell, and relative to cocaine alone in the nucleus accumbens shell. The findings suggest that even though these compounds have different efficacy in the AC bioassy, they produce similar brain activation and attenuation of cocaine hyperlocomotion. Together with our previous research demonstrating that these compounds down-shift the cocaine self-administration dose-effect function, the findings support the idea that D3R-selective compounds may be useful for cocaine dependence medications development.


Asunto(s)
Cocaína/farmacología , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Animales , Cocaína/administración & dosificación , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Cuerpo Estriado/fisiología , Combinación de Medicamentos , Locomoción/efectos de los fármacos , Masculino , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiología , Piperazinas/administración & dosificación , Proteínas Proto-Oncogénicas c-fos/genética , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D3/agonistas
13.
Artículo en Inglés | MEDLINE | ID: mdl-36703567

RESUMEN

Therapeutic release from hydrogels is traditionally controlled by encapsulation within nanoparticles; however, this strategy is limited for the release of proteins due to poor efficiency and denaturation. To overcome this problem, we designed an encapsulation-free release platform where negatively charged proteins are adsorbed to the exterior of transiently cationic nanoparticles, thus allowing the nanoparticles to be formulated separately from the proteins. Release is then governed by the change in nanoparticle surface charge from positive to neutral. To achieve this, we synthesized eight zwitterionic poly(lactide-block-carboxybetaine) copolymer derivatives and formulated them into nanoparticles with differing surface chemistry. The nanoparticles were colloidally stable and lost positive charge at rates dependent on the hydrolytic stability of their surface ester groups. The nanoparticles (NPs) were dispersed in a physically cross-linked hyaluronan-based hydrogel with one of three negatively charged proteins (transferrin, panitumumab, or granulocyte-macrophage colony-stimulating factor) to assess their ability to control release. For all three proteins, dispersing NPs within the gels resulted in significant attenuation of release, with the extent modulated by the hydrolytic stability of the surface groups. Release was rapid from fast-hydrolyzing ester groups, reduced with slow-hydrolyzing bulky ester groups, and very slow with nonhydrolyzing amide groups. When positively charged lysozyme was loaded into the nanocomposite gel, there was no significant attenuation of release compared to gel alone. These data demonstrate that electrostatic interactions between the protein and NP are the primary driver of protein release from the hydrogel. All released proteins retained bioactivity as determined with in vitro cell assays. This release strategy shows tremendous versatility and provides a promising new platform for controlled release of anionic protein therapeutics.

14.
Structure ; 31(8): 958-967.e3, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37279757

RESUMEN

B and T lymphocyte attenuator (BTLA) is an attractive target for a new class of therapeutics that attempt to rebalance the immune system by agonizing checkpoint inhibitory receptors (CIRs). Herpesvirus entry mediator (HVEM) binds BTLA in both trans- and cis-orientations. We report here the development and structural characterization of three humanized BTLA agonist antibodies, 22B3, 25F7, and 23C8. We determined the crystal structures of the antibody-BTLA complexes, showing that these antibodies bind distinct and non-overlapping epitopes of BTLA. While all three antibodies activate BTLA, 22B3 mimics HVEM binding to BTLA and shows the strongest agonistic activity in functional cell assays and in an imiquimod-induced mouse model of psoriasis. 22B3 is also capable of modulating HVEM signaling through the BTLA-HVEM cis-interaction. The data obtained from crystal structures, biochemical assays, and functional studies provide a mechanistic model of HVEM and BTLA organization on the cell surface and informed the discovery of a highly active BTLA agonist.


Asunto(s)
Receptores Inmunológicos , Linfocitos T , Ratones , Animales , Linfocitos T/metabolismo , Receptores Inmunológicos/metabolismo , Anticuerpos/metabolismo
15.
Behav Brain Funct ; 8: 59, 2012 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-23237608

RESUMEN

BACKGROUND: Deficient operant extinction has been hypothesized to be constitutive of ADHD dysfunction. In order to elucidate the behavioral mechanisms underlying this deficit, the performance of an animal model of ADHD, the spontaneously hypertensive rat (SHR), was compared against the performance of a control strain, the Wistar-Kyoto rat (WKY) during extinction. METHOD: Following extensive training of lever pressing under variable interval schedules of food reinforcement (reported previously), SHR and WKY rats were exposed to two sessions of extinction training. Extinction data was analyzed using the Dynamic Bi-Exponential Refractory Model (DBERM) of operant performance. DBERM assumes that operant responses are organized in bouts separated by pauses; during extinction, bouts may decline across multiple dimensions, including frequency and length. DBERM parameters were estimated using hierarchical Bayesian modeling. RESULTS: SHR responded more than WKY during the first extinction session. DBERM parameter estimates revealed that, at the onset of extinction, SHR produced more response bouts than WKY. Over the course of extinction, response bouts progressively shortened for WKY but not for SHR. CONCLUSIONS: Based on prior findings on the sensitivity of DBERM parameters to motivational and schedule manipulations, present data suggests that (1) more frequent response bouts in SHR are likely related to greater incentive motivation, and (2) the persistent length of bouts in SHR are likely related to a slower updating of the response-outcome association. Overall, these findings suggest specific motivational and learning deficits that may explain ADHD-related impairments in operant performance.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Atención/fisiología , Condicionamiento Operante/fisiología , Extinción Psicológica/fisiología , Esquema de Refuerzo , Animales , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Conducta Animal/fisiología , Modelos Animales de Enfermedad , Masculino , Motivación/fisiología , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Especificidad de la Especie
16.
J Immunol ; 185(3): 1949-58, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20592286

RESUMEN

The TNF superfamily member homologous to lymphotoxins, exhibits inducible expression, and competes with HSV glycoprotein D for herpesvirus entry mediator (HVEM), a receptor expressed by T lymphocytes (LIGHT) [TNF superfamily (SF)-14], is a key cytokine that activates T cells and dendritic cells and is implicated as a mediator of inflammatory, metabolic, and malignant diseases. LIGHT engages the lymphotoxin-beta receptor (LTbetaR) and HVEM (TNFRSF14), but is competitively limited in activating these receptors by soluble decoy receptor-3 (DcR3; TNFRSF6B). Two variants in the human LIGHT alter the protein at E214K (rs344560) in the receptor-binding domain and S32L (rs2291667) in the cytosolic domain; however, the functional impact of these polymorphisms is unknown. A neutralizing Ab failed to bind the LIGHT-214K variant, indicating this position as a part of the receptor-binding region. Relative to the predominant reference variant S32/E214, the other variants showed altered avidity with LTbetaR and less with HVEM. Heterotrimers of the LIGHT variants decreased binding avidity to DcR3 and minimized the inhibitory effect of DcR3 toward LTbetaR-induced activation of NF-kappaB. In patients with immune-mediated inflammatory diseases, such as rheumatoid arthritis, DcR3 protein levels were significantly elevated. Immunohistochemistry revealed synoviocytes as a significant source of DcR3 production, and DcR3 hyperexpression is controlled by posttranscriptional mechanisms. The increased potential for LTbetaR signaling, coupled with increased bioavailability due to lower DcR3 avidity, provides a mechanism of how polymorphic variants in LIGHT could contribute to the pathogenesis of inflammatory diseases.


Asunto(s)
Variación Genética/inmunología , Polimorfismo de Nucleótido Simple/inmunología , Miembro 14 de Receptores del Factor de Necrosis Tumoral/metabolismo , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo , Secuencia de Aminoácidos , Disponibilidad Biológica , Técnicas de Cocultivo , Células HeLa , Humanos , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/fisiología , Modelos Inmunológicos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , FN-kappa B/antagonistas & inhibidores , Unión Proteica/genética , Unión Proteica/inmunología , Miembro 14 de Receptores del Factor de Necrosis Tumoral/fisiología , Miembro 6b de Receptores del Factor de Necrosis Tumoral/fisiología , Transducción de Señal/genética , Transducción de Señal/inmunología , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/fisiología
17.
Proc Natl Acad Sci U S A ; 106(15): 6244-9, 2009 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-19332782

RESUMEN

The herpesvirus entry mediator (HVEM; TNFRSF14) activates NF-kappaB through the canonical TNF-related cytokine LIGHT, serving as a costimulatory pathway during activation of T cells. HVEM also functions as a ligand for the Ig superfamily members B and T lymphocyte attenuator (BTLA) and CD160, both of which limit inflammatory responses initiated by T cells. Emerging evidence indicates BTLA also promotes T cell survival, but its structural differences from LIGHT intimate BTLA is unlikely to function as an activator of HVEM. We demonstrate here that BTLA, CD160, and herpes simplex virus envelope glycoprotein D (gD) function as activating ligands for HVEM, promoting NF-kappaB activation and cell survival. Membrane-expressed BTLA and CD160, as well as soluble dimeric receptor surrogates BTLA-Fc and gD-Fc specifically activated HVEM-dependent NF-kappaB. BTLA and CD160 engagement induced recruitment of TNF receptor-associated factor 2 (TRAF2), but not TRAF3, to HVEM that specifically activated the RelA but not the RelB form of NF-kappaB in a mucosal epithelial tumor cell line. Moreover, Btla(-/-) T cells survived poorly following activation but were rescued with BTLA-Fc, indicating HVEM-BTLA bidirectional signaling may serve as a critical cell-survival system for lymphoid and epithelial cells.


Asunto(s)
Miembro 14 de Receptores del Factor de Necrosis Tumoral/inmunología , Transducción de Señal/inmunología , Animales , Antígenos CD/inmunología , Línea Celular , Supervivencia Celular/inmunología , Proteínas Ligadas a GPI , Humanos , Inmunoglobulinas/inmunología , Ligandos , Activación de Linfocitos/inmunología , Ratones , Receptores Inmunológicos/inmunología , Linfocitos T/citología , Linfocitos T/inmunología , Factor 2 Asociado a Receptor de TNF/metabolismo , Factor de Transcripción ReIA/metabolismo , Proteínas del Envoltorio Viral/inmunología
18.
Kaohsiung J Med Sci ; 38(6): 509-516, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35548873

RESUMEN

Amauroderma rugosum (AR) is a basidiomycete in the Ganodermataceae family that has been used traditionally to prevent epileptic attacks and constant crying in babies. However, AR has not been widely studied scientifically. In this review, we summarize the phytochemical components and pharmacological properties of AR that have been reported in the literature. Chemical analyses have revealed that the components of AR include sterols, flavonoids, fatty acids and esters, aromatic acids and esters, phenols, polysaccharides, and triterpenes. Pharmacological properties of AR include antioxidant, anti-inflammatory, neuroprotective, anti-cancer, anti-hyperlipidemic, anti-epileptic, and antibacterial effects. These findings suggest that AR and its bioactive ingredients have potential therapeutic applications, particularly for age-related diseases.


Asunto(s)
Fitoquímicos , Extractos Vegetales , Antiinflamatorios/farmacología , Ésteres , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Extractos Vegetales/química , Polyporaceae
19.
Semin Vasc Surg ; 35(2): 219-227, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35672112

RESUMEN

The increasing prevalence of diabatic foot ulcers (DFUs) is not only costly, but carries a large mortality burden. In this article, we discuss important traditional concepts in the management of DFUs and elaborate on how new technologies have expanded our ability to treat DFUs effectively. New supplies and wound care products have been developed to target the following traditional areas of focus: tissue, infection/inflammation, moisture, and edge. Offloading strategies have grown from standard orthotics or insoles to total contact casting and three-dimensional-printed orthotics to produce the optimum material stiffness for each patient. The concepts of pressure and temperature monitoring have led to the development of multiple devices that transmit continuous monitoring in real time, giving a dynamic picture of plantar stress and training patients in new walking strategies for self-offloading. Surgical approaches have also evolved from the classic surgical debridement and correcting deformities that cause friction to creation of acellular and bio-printed cellular skin substitutes that can be used for grafting. Surveillance and long-term follow-up with a multidisciplinary team have also changed in the face of smartphones and watches that allow patients to monitor themselves in real time with daily prompts and reminders to shape desired behaviors in between clinic visits. Modern technology is changing management of DFUs by expanding on traditional concepts and improving standard therapies.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Pie Diabético/diagnóstico , Pie Diabético/terapia , Humanos , Zapatos
20.
Oxid Med Cell Longev ; 2022: 9266178, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35693699

RESUMEN

Clinical outcomes for doxorubicin (Dox) are limited by its cardiotoxicity but a combination of Dox and agents with cardioprotective activities is an effective strategy to improve its therapeutic outcome. Natural products provide abundant resources to search for novel cardioprotective agents. Ganoderma lucidum (GL) is the most well-known edible mushroom within the Ganodermataceae family. It is commonly used in traditional Chinese medicine or as a healthcare product. Amauroderma rugosum (AR) is another genus of mushroom from the Ganodermataceae family, but its pharmacological activity and medicinal value have rarely been reported. In the present study, the cardioprotective effects of the AR water extract against Dox-induced cardiotoxicity were studied in vitro and in vivo. Results showed that both the AR and GL extracts could potentiate the anticancer effect of Dox. The AR extract significantly decreased the oxidative stress, mitochondrial dysfunction, and apoptosis seen in Dox-treated H9c2 rat cardiomyocytes. However, knockdown of Nrf2 by siRNA abolished the protective effects of AR in these cells. In addition, Dox upregulated the expression of proapoptotic proteins and downregulated the Akt/mTOR and Nrf2/HO-1 signaling pathways, and these effects could be reversed by the AR extract. Consistently, the AR extract significantly prolonged survival time, reversed weight loss, and reduced cardiac dysfunction in Dox-treated mice. In addition, oxidative stress and apoptosis were suppressed, while Nrf2 and HO-1 expressions were elevated in the heart tissues of Dox-treated mice after treatment with the AR extract. However, the GL extract had less cardioprotective effect against Dox in both the cell and animal models. In conclusion, the AR water extract demonstrated a remarkable cardioprotective effect against Dox-induced cardiotoxicity. One of the possible mechanisms for this effect was the upregulation of the mTOR/Akt and Nrf2/HO-1-dependent pathways, which may reduce oxidative stress, mitochondrial dysfunction, and cardiomyocyte apoptosis. These findings suggested that AR may be beneficial for the heart, especially in patients receiving Dox-based chemotherapy.


Asunto(s)
Cardiotoxicidad , Factor 2 Relacionado con NF-E2 , Animales , Ratones , Ratas , Apoptosis , Cardiotoxicidad/tratamiento farmacológico , Cardiotoxicidad/genética , Cardiotoxicidad/prevención & control , Doxorrubicina/toxicidad , Hemo Oxigenasa (Desciclizante)/metabolismo , Hemo-Oxigenasa 1/metabolismo , Proteínas de la Membrana/metabolismo , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Polyporaceae , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
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