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Prevailing hypotheses on the mechanisms of antidepressant action posit that antidepressants directly counteract deficiencies in major neurotransmitter signaling systems that underlie depression. The rapidly acting antidepressant ketamine has been postulated to correct excess glutamatergic signaling via glutamatergic antagonism leading to the rescue of neuronal structural deficits and reversal of behavioral symptoms. We studied this premise using systemic administration of the acetylcholinesterase inhibitor physostigmine, which has been shown to rapidly elicit a shorter-term period of depressed mood in humans via cholinergic mechanisms. We observed that physostigmine induces acute stress in tandem with long term depression of glutamate release in the hippocampus of mice. However, ketamine rapidly acts to re-establish glutamatergic synaptic efficacy via postsynaptic signaling and behaviorally masks the reduction in passive coping induced by physostigmine. These results underscore the divergence of synaptic signaling mechanisms underlying mood changes and antidepressant action and highlight how distinct synaptic mechanisms may underlie neuropsychiatric disorders versus their treatment.
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BACKGROUND: Stress profoundly affects physical and emotional well-being, extending its physiological influence to the female menstrual cycle, impeding the hypothalamus-pituitary-gonadal (HPG) axis, and affecting fertility by suppressing sex-stimulating hormones. METHODS: In this study, we meticulously analyzed menstrual cycles and corresponding hormonal fluctuations in three female Cynomolgus monkeys. RESULTS: The preliminary findings indicated lower-than-normal levels of cortisol, follicle-stimulating hormone (FSH), and estradiol. Anovulatory bleeding occurred in one monkey, which could be linked to stress. In contrast to cortisol, alkaline phosphatase (ALP), which is correlated to cortisol levels, was consistently elevated in menstruating monkeys, suggesting its potential as a stress indicator. The non-menstruating group exhibited stress-related weight loss, emphasizing the observed ALP trends. CONCLUSIONS: Non-menstruating monkeys may experience more stress than menstruating monkeys. The implications of this study extend beyond the confines of primate studies and offer a valuable method for enhancing the welfare of female Cynomolgus monkeys.
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Estradiol , Hidrocortisona , Macaca fascicularis , Ciclo Menstrual , Estresse Fisiológico , Animais , Macaca fascicularis/fisiologia , Feminino , Estradiol/sangue , Ciclo Menstrual/fisiologia , Hidrocortisona/sangue , Estresse Fisiológico/fisiologia , Hormônio Foliculoestimulante/sangue , Estresse PsicológicoRESUMO
Positive reinforcement and training for health optimization are pivotal for successful studies with monkeys. Potential food inclination is important for studies on crab-eating macaques in laboratory environments, but evaluations remain scarce. We explored crab-eating macaques' potential food inclination to establish a reward system for future behavioral assessments. Twelve male and three female monkeys underwent a food inclination assessment in which they were offered four food categories-fruits, vegetables, proteins, and nuts. The monkeys exhibited a higher inclination for plant-based foods, particularly fruits and vegetables, over animal-based proteins like chicken and tuna (p < 0.0001), with a notable inclination for nuts (eaten/provided = 100%). Additionally, the consistency of potential food inclination after repeated offerings was investigated, revealing a time-dependent increase in inclination for protein items. Food consumption ratios correlated positively with caloric intake (r = 0.59, p = 0.02), implying that individuals with a regular high caloric intake and increased body weight are more likely to accept food during positive reinforcement training. Our findings suggest fruits, vegetables, protein-rich foods, and nuts can help with health optimization. However, animal-based protein-rich foods initially had a low preference, which may increase over time. Our study can provide guidelines for positive reinforcement training and health optimization.
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Depression is a debilitating mood disorder that causes persistent feelings of sadness, emptiness, and a loss of joy. However, the clinical efficacy of representative drugs for depression, such as selective serotonin reuptake inhibitors, remains controversial. Therefore, there is an urgent need for more effective therapies to treat depression. Neuroinflammation and the hypothalamic-pituitary-adrenal (HPA) axis are pivotal factors in depression. Inulae Flos (IF), the flower of Inula japonica Thunb, is known for its antioxidant and anti-inflammatory effects. This study explored whether IF alleviates depression in both in vitro and in vivo models. For in vitro studies, we treated BV2 and PC12 cells damaged by lipopolysaccharides or corticosterone (CORT) with IF to investigate the mechanisms of depression. For in vivo studies, C57BL/6 mice were exposed to chronic restraint stress and were administered IF at doses of 0, 100, and 300 mg/kg for 2 weeks. IF inhibited pro-inflammatory mediators, such as nitric oxide, inducible nitric oxide synthase, and interleukins in BV2 cells. Moreover, IF increased the viability of CORT-damaged PC12 cells by modulating protein kinase B, a mammalian target of the rapamycin pathway. Behavioral assessments demonstrated that IF reduced depression-like behaviors in mice. We found that IF reduced the activation of microglia and astrocytes, and regulated synapse plasticity in the mice brains. Furthermore, IF lowered elevated CORT levels in the plasma and restored glucocorticoid receptor expression in the hypothalamus. Collectively, these findings suggest that IF can alleviate depression by mitigating neuroinflammation and recovering dysfunction of the HPA-axis.
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Post-traumatic stress disorder (PTSD) is a mental illness that can occur in individuals who have experienced trauma. Current treatments for PTSD, typically serotonin reuptake inhibitors, have limited effectiveness for patients and often cause serious adverse effects. Therefore, a novel class of treatment with better pharmacological profile is necessary. D-Pinitol has been reported to be effective for depression and anxiety disorders, but there are no reports associated with PTSD. In the present study, we investigated the effects of D-pinitol in a mouse model of PTSD induced by a single prolonged stress (SPS) protocol. We examined the therapeutic effects of D-pinitol on emotional and cognitive impairments in the SPS mouse model. We also investigated the effects of D-pinitol on fear memory formation. Mineralocorticoid receptor transactivation assay, Western blot, and quantitative PCR were employed to investigate how D-pinitol exerts its pharmacological activities. D-Pinitol ameliorated PTSD-like behaviors in a SPS mouse model. D-Pinitol also normalized the increased mRNA expression levels and protein levels of the mineralocorticoid receptor in the amygdala. A mineralocorticoid receptor agonist reversed the effects of D-pinitol on fear extinction and recall, and the antagonistic property of D-pinitol against the mineralocorticoid receptor was confirmed in vitro. Our findings suggest that D-pinitol could serve as a potential therapeutic agent for PTSD due to its antagonistic effect on the mineralocorticoid receptor.
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Inositol/análogos & derivados , Transtornos de Estresse Pós-Traumáticos , Camundongos , Humanos , Animais , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/psicologia , Medo/fisiologia , Extinção Psicológica , Receptores de Mineralocorticoides/metabolismo , Receptores de Mineralocorticoides/uso terapêutico , Modelos Animais de Doenças , Estresse Psicológico/psicologiaRESUMO
Major depressive disorder (MDD) is a leading cause of suicide in the world. Monoamine-based antidepressant drugs are a primary line of treatment for this mental disorder, although the delayed response and incomplete efficacy in some patients highlight the need for improved therapeutic approaches. Over the past two decades, ketamine has shown rapid onset with sustained (up to several days) antidepressant effects in patients whose MDD has not responded to conventional antidepressant drugs. Recent preclinical studies have started to elucidate the underlying mechanisms of ketamine's antidepressant properties. Herein, we describe and compare recent clinical and preclinical findings to provide a broad perspective of the relevant mechanisms for the antidepressant action of ketamine.
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Transtorno Depressivo Maior , Ketamina , Humanos , Ketamina/uso terapêutico , Depressão/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Antidepressivos/uso terapêutico , Aminas/uso terapêuticoRESUMO
BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid-ß (Aß) and excessive neuroinflammation, resulting in neuronal cell death and cognitive impairments. Eugenol, a phenylpropene, is the main component of Syzygium aromaticum L. (Myrtaceae) and has multiple therapeutic effects, including neuroprotective and anti-inflammatory effects, through multimodal mechanisms. PURPOSE: We aimed to investigate the effect of eugenol on AD pathologies using a 5× familiar AD (5×FAD) mouse model. METHODS: Eight-month-old 5×FAD and wild-type mice were administered with eugenol (10 or 30 mg/kg/day, p.o) for 2 months. Y-maze and Morris water maze tests were performed to assess the cognitive function of mice. After the behavioral test, molecular analysis was conducted to investigate the therapeutic mechanism of eugenol. RESULTS: Our findings indicate that eugenol treatment effectively mitigated cognitive impairments in 5×FAD mice. This beneficial effect was associated with a decrease in AD pathologies, including neuronal cell loss and Aß deposition. Specifically, eugenol inhibited necroptosis activation and increased microglial phagocytosis, which were the underlying mechanisms for the observed reductions in neuronal cell loss and Aß deposition, respectively. CONCLUSION: Overall, our data suggest that eugenol would be a potential therapeutic candidate for AD.
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Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Animais , Doença de Alzheimer/metabolismo , Eugenol/farmacologia , Eugenol/uso terapêutico , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de DoençasRESUMO
Acute administration of (R,S)-ketamine (ketamine) produces rapid antidepressant effects that in some patients can be sustained for several days to more than a week. Ketamine blocks N-methyl-d-asparate (NMDA) receptors (NMDARs) to elicit specific downstream signaling that induces a novel form of synaptic plasticity in the hippocampus that has been linked to the rapid antidepressant action. These signaling events lead to subsequent downstream transcriptional changes that are involved in the sustained antidepressant effects. Here we review how ketamine triggers this intracellular signaling pathway to mediate synaptic plasticity which underlies the rapid antidepressant effects and links it to downstream signaling and the sustained antidepressant effects.
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Ketamina , Humanos , Ketamina/farmacologia , Ketamina/uso terapêutico , Ketamina/metabolismo , Depressão/tratamento farmacológico , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Antidepressivos/metabolismo , Hipocampo , Transdução de SinaisRESUMO
Although the use of IVIg has increased in various immune-driven diseases and even in pregnancy, the exact action mechanisms of IVIg are not fully understood. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN) is a known receptor for α-2,6-sialylated IgG (sIVIg), which is responsible for the anti-inflammatory effect of IVIg. DC-SIGN is expressed on Hofbauer cells (HBCs) of the fetal villi of the placenta which act as an innate immune modulator at the maternal-fetal interface. Preeclampsia is a major complication in pregnancy and is related to IL-10, a cytokine with an important role in immune tolerance. DC-SIGN interaction with sIVIg in HBCs promoted IL-10 secretion through the activation of the caveolin-1/NF-κB pathway, especially in plasma lipid rafts. Consistent results were obtained for HBCs from patients with preeclampsia. Collectively, the stimulation of DC-SIGN+ HBCs with sIVIg enhanced immune tolerance in the feto-maternal environment, suggesting the therapeutic application of sIVIg to prevent preeclampsia.
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Imunoglobulinas Intravenosas , Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , NF-kappa B/metabolismo , Interleucina-10/metabolismo , Caveolina 1/metabolismo , Lectinas Tipo C/metabolismo , Tolerância Imunológica , Células DendríticasRESUMO
BACKGROUND: Two injectable anti-osteoporosis medications, denosumab and zoledronic acid, have been widely used to treat patients with severe osteoporosis. The purpose of this study was to evaluate the real-world effectiveness and adherence of denosumab compared to zoledronic acid in geriatric patients after a hip fracture. METHODS: A total of 282 patients treated with osteoporotic hip fracture between March 2014 and Aug 2022 were retrospectively reviewed. The patients were asked to select the anti-osteoporosis medication after surgery. Treatment persistence was monitored by follow-up visit to the outpatient clinic at postoperative 2 years. RESULTS: Of 282 individuals with baseline data, 162 patients took subcutaneous denosumab and 120 patients took intravenous zoledronic acid. At postoperative 2 years, the change in bone mineral density (BMD) from baseline was greater in the denosumab group compared with the zoledronic acid group (p < 0.001). The rate of persistence to denosumab was significantly higher than that for 12-months zoledronic acid (p = 0.01). Serious adverse events were similar in the two groups. CONCLUSIONS: Our study revealed the effectiveness and patients' persistence for two commonly used anti-osteoporosis agents after hip fracture. In this frail, elderly population, half-yearly denosumab was superior to yearly zoledronic acid in BMD and demonstrated significant higher persistence rate, indicating a potential therapeutic advantage that warrants further validation.
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Conservadores da Densidade Óssea , Fraturas do Quadril , Osteoporose Pós-Menopausa , Osteoporose , Fraturas por Osteoporose , Humanos , Idoso , Feminino , Ácido Zoledrônico/uso terapêutico , Denosumab/uso terapêutico , Estudos Retrospectivos , Osteoporose/complicações , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/cirurgia , Densidade Óssea , Fraturas do Quadril/cirurgia , Difosfonatos/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológicoRESUMO
The precise manipulation of the neural stem cell (NSC)-derived neural differentiation is still challenging, and there is a technological barrier to regulate the axonal regeneration in a controlled manner. Here, we developed a microfluidic chip integrated with a microelectrode array as an axonal guidance platform. The microfluidic electrode array chip consisted of two compartments and a bridge microchannel that could isolate and guide the axons. We demonstrated that the NSCs were largely differentiated into neural cells as the electric field was applied to the microfluidic electrode array chip. We also confirmed the synergistic effects of the electrical stimulation (ES) and neurotrophic factor (NF) on axonal outgrowth. This microfluidic electrode array chip can serve as a central nervous system (CNS) model for axonal injury and regeneration. Therefore, it could be a potentially powerful tool for an in vitro model of the axonal regeneration.
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Axônios , Microfluídica , Axônios/fisiologia , Estimulação Elétrica , Microeletrodos , Regeneração Nervosa/fisiologia , NeurôniosRESUMO
Photoplethysmography (PPG) is easy to measure and provides important parameters related to heart rate and arrhythmia. However, automated PPG methods have not been developed because of their susceptibility to motion artifacts and differences in waveform characteristics among individuals. With increasing use of telemedicine, there is growing interest in application of deep neural network (DNN) technology for efficient analysis of vast amounts of PPG data. This study is about an algorithm for measuring a patient's PPG and comparing it with their own data stored previously and with the average data of several groups. Six deep neural networks were used to normalize the PPG waveform according to the heart rate by removing uninformative regions from the PPG, distinguishing between heartbeat and reflection pulses, dividing the heartbeat waveform into 10 segments and averaging the values according to each segments. PPG data were measured using telemedicine in both groups. Group 1 consisted of healthy people aged 25 to 35 years, and Group 2 consisted of patients between 60 and 75 years of age taking antihypertensive medications. The proposed algorithm could accurately determine which group the subject belonged with the newly measured PPG data (AUC = 0.998). On the other hand, errors were frequently observed in identification of individuals (AUC = 0.819).
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Frequência Cardíaca , Movimento (Física) , Redes Neurais de Computação , Fotopletismografia , Processamento de Sinais Assistido por Computador , Adulto , Feminino , Humanos , MasculinoRESUMO
Prenatal exposure to valproic acid (VPA) has been implicated in the manifestation of autism spectrum disorder (ASD)-like behavioral and functional changes both in human and rodents including mice and rats. The objective of this study was to determine metabolomics profiling and biomarkers related to VPA-induced symptoms resembling ASD using proton nuclear magnetic resonance (1H-NMR) spectral data. VPA was administered to pregnant rats at gestation day 12.5 and effects measured subsequently in male 4-week-old offspring pups. The sociability of VPA-treated animals was significantly diminished and exhibited ASD-like behavior as evidenced by reduction of social adaptation disorder and lack of social interactions. To find biomarkers related to ASD, the following were collected prefrontal brain cortices, urine bladder and blood samples directly from heart puncture. In all samples, principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) displayed significant clustering pattern differences between control and treated groups. Valine, taurine, myo-inositol, 3-hydroxybutyrate and 1,3-dihydroxyacetone were significantly decreased in brain cortices in treated rats. Serum metabolites of glucose, creatine phosphate, lactate, glutamine and threonine were significantly increased in VPA-administered animals. Urinary metabolites of pimelate, 3-hydroxyisovalerate and valerate were significantly reduced in VPA-treated rat, whereas galactose and galactonate levels were elevated. Various metabolites were associated with mitochondrial dysfunction metabolism and central nervous system disorders. Data demonstrated that VPA-induced alterations in endogenous metabolites of serum, urine, and brain cortex which might prove useful as biomarkers for symptoms resembling ASD as a model of this disorder.
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Transtorno do Espectro Autista/metabolismo , Modelos Animais de Doenças , Ácido Valproico/toxicidade , Animais , Transtorno do Espectro Autista/etiologia , Biomarcadores/metabolismo , Encéfalo/metabolismo , Feminino , Masculino , Exposição Materna/efeitos adversos , Metabolômica , Espectroscopia de Prótons por Ressonância Magnética , RatosRESUMO
Ketamine is a noncompetitive glutamatergic N-methyl-d-aspartate receptor (NMDAR) antagonist that exerts rapid antidepressant effects. Preclinical studies identify eukaryotic elongation factor 2 kinase (eEF2K) signaling as essential for the rapid antidepressant action of ketamine. Here, we combine genetic, electrophysiological, and pharmacological strategies to investigate the role of eEF2K in synaptic function and find that acute, but not chronic, inhibition of eEF2K activity induces rapid synaptic scaling in the hippocampus. Retinoic acid (RA) signaling also elicits a similar form of rapid synaptic scaling in the hippocampus, which we observe is independent of eEF2K functioni. The RA signaling pathway is not required for ketamine-mediated antidepressant action; however, direct activation of the retinoic acid receptor α (RARα) evokes rapid antidepressant action resembling ketamine. Our findings show that ketamine and RARα activation independently elicit a similar form of multiplicative synaptic scaling that is causal for rapid antidepressant action.
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Antidepressivos/farmacologia , Região CA1 Hipocampal/efeitos dos fármacos , Ketamina/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Tretinoína/farmacologia , Animais , Região CA1 Hipocampal/metabolismo , Quinase do Fator 2 de Elongação/genética , Quinase do Fator 2 de Elongação/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Receptor alfa de Ácido Retinoico/agonistas , Receptor alfa de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico/metabolismo , Sinapses/metabolismo , Fatores de TempoRESUMO
The rapidly acting antidepressants ketamine and scopolamine exert behavioral effects that can last from several days to more than a week in some patients. The molecular mechanisms underlying the maintenance of these antidepressant effects are unknown. Here we show that methyl-CpG-binding protein 2 (MeCP2) phosphorylation at Ser421 (pMeCP2) is essential for the sustained, but not the rapid, antidepressant effects of ketamine and scopolamine in mice. Our results reveal that pMeCP2 is downstream of BDNF, a critical factor in ketamine and scopolamine antidepressant action. In addition, we show that pMeCP2 is required for the long-term regulation of synaptic strength after ketamine or scopolamine administration. These results demonstrate that pMeCP2 and associated synaptic plasticity are essential determinants of sustained antidepressant effects.
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Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Proteína 2 de Ligação a Metil-CpG/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Ketamina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasticidade Neuronal/fisiologia , Fosforilação , Escopolamina/farmacologiaRESUMO
Ketamine is a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist that produces rapid antidepressant action in some patients with treatment-resistant depression. However, recent data suggest that â¼50% of patients with treatment-resistant depression do not respond to ketamine. The factors that contribute to the nonresponsiveness to ketamine's antidepressant action remain unclear. Recent studies have reported a role for secreted glycoprotein Reelin in regulating pre- and postsynaptic function, which suggests that Reelin may be involved in ketamine's antidepressant action, although the premise has not been tested. Here, we investigated whether the disruption of Reelin-mediated synaptic signaling alters ketamine-triggered synaptic plasticity and behavioral effects. To this end, we used mouse models with genetic deletion of Reelin or apolipoprotein E receptor 2 (Apoer2), as well as pharmacological inhibition of their downstream effectors, Src family kinases (SFKs) or phosphoinositide 3-kinase. We found that disruption of Reelin, Apoer2, or SFKs blocks ketamine-driven behavioral changes and synaptic plasticity in the hippocampal CA1 region. Although ketamine administration did not affect tyrosine phosphorylation of DAB1, an adaptor protein linked to downstream signaling of Reelin, disruption of Apoer2 or SFKs impaired baseline NMDA receptor-mediated neurotransmission. These results suggest that maintenance of baseline NMDA receptor function by Reelin signaling may be a key permissive factor required for ketamine's antidepressant effects. Taken together, our results suggest that impairments in Reelin-Apoer2-SFK pathway components may in part underlie nonresponsiveness to ketamine's antidepressant action.
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Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Ketamina/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Proteína Reelina/fisiologia , Animais , Proteínas Relacionadas a Receptor de LDL/fisiologia , Masculino , Camundongos , Plasticidade Neuronal/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/fisiologiaRESUMO
Blended hydrogels play an important role in enhancing the properties (e.g., mechanical properties and conductivity) of hydrogels. In this study, we generated a conductive blended hydrogel, which was achieved by mixing gelatin methacrylate (GelMA) with collagen, and silver nanowire (AgNW). The ratio of GelMA, collagen and AgNW was optimized and was subsequently gelated by ultraviolet light (UV) and heat. The scanning electron microscope (SEM) image of the conductive blended hydrogels showed that collagen and AgNW were present in the GelMA hydrogel. Additionally, rheological analysis indicated that the mechanical properties of the conductive GelMA-collagen-AgNW blended hydrogels improved. Biocompatibility analysis confirmed that the human umbilical vein endothelial cells (HUVECs) encapsulated within the three-dimensional (3D), conductive blended hydrogels were highly viable. Furthermore, we confirmed that the molecule in the conductive blended hydrogel was released by electrical stimuli-mediated structural deformation. Therefore, this conductive GelMA-collagen-AgNW blended hydrogel could be potentially used as a smart actuator for drug delivery applications.
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The combination therapy based on multifunctional nanocomposites has been considered as a promising approach to improve cancer therapeutic efficacy. Herein, we report targeted multi-functional poly(N-isopropylacrylamide) (PNIPAM)-based nanocomposites for synergistic chemo-photothermal therapy toward breast cancer cells. To increase the transition temperature, acrylic acid (AAc) was added in synthetic process of PNIPAM, showing that the intrinsic lower critical solution temperature was changed to 42 °C . To generate the photothermal effect under near-infrared (NIR) laser irradiation (808 nm), polypyrrole (ppy) nanoparticles were uniformly decorated in PNIPAM-AAc. Folic acid (FA), as a cancer targeting ligand, was successfully conjugated on the surplus carboxyl groups in PNIPAM network. The drug release of PNIPAM-ppy-FA nanocomposites was efficiently triggered in response to the temperature change by NIR laser irradiation. We also confirmed that PNIPAM-ppy-FA was internalized to MDA-MB-231 breast cancer cells by folate-receptor-mediated endocytosis and significantly enhanced cancer therapeutic efficacy with combination treatment of chemo-photothermal effects. Therefore, our work encourages further exploration of multi-functional nanocarrier agents for synergistic therapeutic approaches to different types of cancer cells.
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Valproic acid is a clinically used mood stabilizer and antiepileptic drug. Valproic acid has been suggested as a teratogen associated with the manifestation of neurodevelopmental disorders, such as fetal valproate syndrome and autism spectrum disorders, when taken during specific time window of pregnancy. Previous studies proposed that prenatal exposure to valproic acid induces abnormal proliferation and differentiation of neural progenitor cells, presumably by inhibiting histone deacetylase and releasing the condensed chromatin structure. Here, we found valproic acid up-regulates the transcription of T-type calcium channels by inhibiting histone deacetylase in neural progenitor cells. The pharmacological blockade of T-type calcium channels prevented the increased proliferation of neural progenitor cells induced by valproic acid. Differentiated neural cells from neural progenitor cells treated with valproic acid displayed increased levels of calcium influx in response to potassium chloride-induced depolarization. These results suggest that prenatal exposure to valproic acid up-regulates T-type calcium channels, which may contribute to increased proliferation of neural progenitor cells by inducing an abnormal calcium response and underlie the pathogenesis of neurodevelopmental disorders.