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1.
Cell ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38959890

RESUMEN

Hypothalamic neural circuits regulate instinctive behaviors such as food seeking, the fight/flight response, socialization, and maternal care. Here, we identified microdeletions on chromosome Xq23 disrupting the brain-expressed transient receptor potential (TRP) channel 5 (TRPC5). This family of channels detects sensory stimuli and converts them into electrical signals interpretable by the brain. Male TRPC5 deletion carriers exhibited food seeking, obesity, anxiety, and autism, which were recapitulated in knockin male mice harboring a human loss-of-function TRPC5 mutation. Women carrying TRPC5 deletions had severe postpartum depression. As mothers, female knockin mice exhibited anhedonia and depression-like behavior with impaired care of offspring. Deletion of Trpc5 from oxytocin neurons in the hypothalamic paraventricular nucleus caused obesity in both sexes and postpartum depressive behavior in females, while Trpc5 overexpression in oxytocin neurons in knock-in mice reversed these phenotypes. We demonstrate that TRPC5 plays a pivotal role in mediating innate human behaviors fundamental to survival, including food seeking and maternal care.

2.
J Neurosci ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38897723

RESUMEN

Light plays an essential role in a variety of physiological processes, including vision, mood, and glucose homeostasis. However, the intricate relationship between light and an animal's feeding behavior has remained elusive. Here, we found that light exposure suppresses food intake, whereas darkness amplifies it in male mice. Interestingly, this phenomenon extends its reach to diurnal male Nile grass rats and healthy humans. We further show that lateral habenula (LHb) neurons in mice respond to light exposure, which in turn activates 5-HT neurons in the dorsal Raphe nucleus (DRN). Activation of the LHb → 5-HTDRN circuit in mice blunts darkness-induced hyperphagia, while inhibition of the circuit prevents light-induced anorexia. Together, we discovered a light responsive neural circuit that relays the environmental light signals to regulate feeding behavior in mice.Significance statement Feeding behavior is influenced by a myriad of sensory inputs, but the impact of light exposure on feeding regulation has remained enigmatic. Here, we showed that light exposure diminishes food intake across both nocturnal and diurnal species. Delving deeper, our findings revealed that the LHb → 5-HTDRN neural circuit plays a pivotal role in mediating light-induced anorexia in mice. These discoveries not only enhance our comprehension of the intricate neuronal mechanisms governing feeding in response to light but also offer insights for developing innovative strategies to address obesity and eating disorders.

3.
Sci Adv ; 10(26): eadl2675, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941473

RESUMEN

Declined memory is a hallmark of Alzheimer's disease (AD). Experiments in rodents and human postmortem studies suggest that serotonin (5-hydroxytryptamine, 5-HT) plays a role in memory, but the underlying mechanisms are unknown. Here, we investigate the role of 5-HT 2C receptor (5-HT2CR) in regulating memory. Transgenic mice expressing a humanized HTR2C mutation exhibit impaired plasticity of hippocampal ventral CA1 (vCA1) neurons and reduced memory. Further, 5-HT neurons project to and synapse onto vCA1 neurons. Disruption of 5-HT synthesis in vCA1-projecting neurons or deletion of 5-HT2CRs in the vCA1 impairs neural plasticity and memory. We show that a selective 5-HT2CR agonist, lorcaserin, improves synaptic plasticity and memory in an AD mouse model. Cumulatively, we demonstrate that hippocampal 5-HT2CR signaling regulates memory, which may inform the use of 5-HT2CR agonists in the treatment of dementia.


Asunto(s)
Enfermedad de Alzheimer , Memoria , Ratones Transgénicos , Plasticidad Neuronal , Receptor de Serotonina 5-HT2C , Animales , Humanos , Receptor de Serotonina 5-HT2C/metabolismo , Receptor de Serotonina 5-HT2C/genética , Memoria/efectos de los fármacos , Memoria/fisiología , Ratones , Plasticidad Neuronal/efectos de los fármacos , Enfermedad de Alzheimer/metabolismo , Hipocampo/metabolismo , Hipocampo/efectos de los fármacos , Serotonina/metabolismo , Modelos Animales de Enfermedad , Región CA1 Hipocampal/metabolismo , Región CA1 Hipocampal/efectos de los fármacos , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Agonistas del Receptor de Serotonina 5-HT2/farmacología
4.
Endocrinology ; 165(7)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38815086

RESUMEN

The serotonin 2C receptor (5-HT2CR)-melanocortin pathway plays well-established roles in the regulation of feeding behavior and body weight homeostasis. Dysfunctions in this system, such as loss-of-function mutations in the Htr2c gene, can lead to hyperphagia and obesity. In this study, we aimed to investigate the potential therapeutic strategies for ameliorating hyperphagia, hyperglycemia, and obesity associated with a loss-of-function mutation in the Htr2c gene (Htr2cF327L/Y). We demonstrated that reexpressing functional 5-HT2CR solely in hypothalamic pro-opiomelanocortin (POMC) neurons is sufficient to reduce food intake and body weight in Htr2cF327L/Y mice subjected to a high-fat diet (HFD). In addition, 5-HT2CR expression restores the responsiveness of POMC neurons to lorcaserin, a selective agonist for 5-HT2CR. Similarly, administration of melanotan II, an agonist of the melanocortin receptor 4 (MC4R), effectively suppresses feeding and weight gain in Htr2cF327L/Y mice. Strikingly, promoting wheel-running activity in Htr2cF327L/Y mice results in a decrease in HFD consumption and improved glucose homeostasis. Together, our findings underscore the crucial role of the melanocortin system in alleviating hyperphagia and obesity related to dysfunctions of the 5-HT2CR, and further suggest that MC4R agonists and lifestyle interventions might hold promise in counteracting hyperphagia, hyperglycemia, and obesity in individuals carrying rare variants of the Htr2c gene.


Asunto(s)
Dieta Alta en Grasa , Hiperfagia , Obesidad , Proopiomelanocortina , Receptor de Melanocortina Tipo 4 , Receptor de Serotonina 5-HT2C , Animales , Receptor de Serotonina 5-HT2C/metabolismo , Receptor de Serotonina 5-HT2C/genética , Masculino , Ratones , Hiperfagia/metabolismo , Hiperfagia/genética , Proopiomelanocortina/metabolismo , Proopiomelanocortina/genética , Obesidad/metabolismo , Obesidad/genética , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/metabolismo , Receptor de Melanocortina Tipo 4/agonistas , alfa-MSH/farmacología , alfa-MSH/análogos & derivados , Mutación con Pérdida de Función , Hipotálamo/metabolismo , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Ingestión de Alimentos/genética , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Modelos Animales de Enfermedad , Hiperglucemia/metabolismo , Hiperglucemia/genética , Ratones Endogámicos C57BL , Benzazepinas , Péptidos Cíclicos
5.
bioRxiv ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38746314

RESUMEN

Obesity is a growing global health epidemic with limited effective therapeutics. Serotonin (5-HT) is one major neurotransmitter which remains an excellent target for new weight-loss therapies, but there remains a gap in knowledge on the mechanisms involved in 5-HT produced in the dorsal Raphe nucleus (DRN) and its involvement in meal initiation. Using a closed-loop optogenetic feeding paradigm, we showed that the 5-HTDRN→arcuate nucleus (ARH) circuit plays an important role in regulating meal initiation. Incorporating electrophysiology and ChannelRhodopsin-2-Assisted Circuit Mapping, we demonstrated that 5-HTDRN neurons receive inhibitory input partially from GABAergic neurons in the DRN, and the 5-HT response to GABAergic inputs can be enhanced by hunger. Additionally, deletion of the GABAA receptor subunit in 5-HT neurons inhibits meal initiation with no effect on the satiation process. Finally, we identified the instrumental role of dopaminergic inputs via dopamine receptor D2 in 5-HTDRN neurons in enhancing the response to GABA-induced feeding. Thus, our results indicate that 5-HTDRN neurons are inhibited by synergistic inhibitory actions of GABA and dopamine, which allows for the initiation of a meal.

6.
Front Plant Sci ; 15: 1344143, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38410736

RESUMEN

Protein, oil content, linoleic acid, and lignan are several key indicators for evaluating the quality of flaxseed. In order to optimize the testing methods for flaxseed's nutritional quality and enhance the efficiency of screening high-quality flax germplasm resources, we selected 30 flaxseed species widely cultivated in Northwest China as the subjects of our study. Firstly, we gathered hyperspectral information regarding the seeds, along with data on protein, oil content, linoleic acid, and lignan, and utilized the SPXY algorithm to classify the sample set. Subsequently, the spectral data underwent seven distinct preprocessing methods, revealing that the PLSR model exhibited superior performance after being processed with the SG smoothing method. Feature wavelength extraction was carried out using the Successive Projections Algorithm (SPA) and the Competitive Adaptive Reweighted Sampling (CARS). Finally, four quantitative analysis models, namely Partial Least Squares Regression (PLSR), Support Vector Regression (SVR), Multiple Linear Regression (MLR), and Principal Component Regression (PCR), were individually established. Experimental results demonstrated that among all the models for predicting protein content, the SG-CARS-MLR model predicted the best, with and of 0.9563 and 0.9336, with the corresponding Root Mean Square Error Correction (RMSEC) and Root Mean Square Error Prediction (RMSEP) of 0.4892 and 0.5616, respectively. In the optimal prediction models for oil content, linoleic acid and lignan, the Rp2 was 0.8565, 0.8028, 0.9343, and the RMSEP was 0.8682, 0.5404, 0.5384, respectively. The study results show that hyperspectral imaging technology has excellent potential for application in the detection of quality characteristics of flaxseed and provides a new option for the future non-destructive testing of the nutritional quality of flaxseed.

7.
Front Immunol ; 14: 1225557, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38130718

RESUMEN

Introduction: The World Health Organization (WHO) has assessed the global public risk of monkeypox as moderate, and 71 WHO member countries have reported more than 14,000 cases of monkeypox infection. At present, the identification of clinical symptoms of monkeypox mainly depends on traditional medical means, which has the problems of low detection efficiency and high detection cost. The deep learning algorithm is excellent in image recognition and can extract and recognize image features quickly and reliably. Methods: Therefore, this paper proposes a residual convolutional neural network based on the λ function and contextual transformer (LaCTResNet) for the image recognition of monkeypox cases. Results: The average recognition accuracy of the neural network model is 91.85%, which is 15.82% higher than that of the baseline model ResNet50 and better than the classical convolutional neural networks models such as AlexNet, VGG16, Inception-V3, and EfficientNet-B5. Discussion: This method realizes high-precision identification of skin symptoms of the monkeypox virus to provide a fast and reliable auxiliary diagnosis method for monkeypox cases for front-line medical staff.


Asunto(s)
Mpox , Humanos , Mpox/diagnóstico , Redes Neurales de la Computación , Algoritmos
8.
J Clin Invest ; 133(14)2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37261917

RESUMEN

Glucose is the basic fuel essential for maintenance of viability and functionality of all cells. However, some neurons - namely, glucose-inhibited (GI) neurons - paradoxically increase their firing activity in low-glucose conditions and decrease that activity in high-glucose conditions. The ionic mechanisms mediating electric responses of GI neurons to glucose fluctuations remain unclear. Here, we showed that currents mediated by the anoctamin 4 (Ano4) channel are only detected in GI neurons in the ventromedial hypothalamic nucleus (VMH) and are functionally required for their activation in response to low glucose. Genetic disruption of the Ano4 gene in VMH neurons reduced blood glucose and impaired counterregulatory responses during hypoglycemia in mice. Activation of VMHAno4 neurons increased food intake and blood glucose, while chronic inhibition of VMHAno4 neurons ameliorated hyperglycemia in a type 1 diabetic mouse model. Finally, we showed that VMHAno4 neurons represent a unique orexigenic VMH population and transmit a positive valence, while stimulation of neurons that do not express Ano4 in the VMH (VMHnon-Ano4) suppress feeding and transmit a negative valence. Together, our results indicate that the Ano4 channel and VMHAno4 neurons are potential therapeutic targets for human diseases with abnormal feeding behavior or glucose imbalance.


Asunto(s)
Glucosa , Hipoglucemia , Animales , Ratones , Anoctaminas , Glucemia , Glucosa/farmacología , Hipoglucemia/genética , Hipotálamo/metabolismo , Neuronas/metabolismo , Núcleo Hipotalámico Ventromedial/metabolismo
9.
Nat Metab ; 5(1): 147-164, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36593271

RESUMEN

Leptin acts on hypothalamic neurons expressing agouti-related protein (AgRP) or pro-opiomelanocortin (POMC) to suppress appetite and increase energy expenditure, but the intracellular mechanisms that modulate central leptin signalling are not fully understood. Here we show that growth factor receptor-bound protein 10 (Grb10), an adaptor protein that binds to the insulin receptor and negatively regulates its signalling pathway, can interact with the leptin receptor and enhance leptin signalling. Ablation of Grb10 in AgRP neurons promotes weight gain, while overexpression of Grb10 in AgRP neurons reduces body weight in male and female mice. In parallel, deletion or overexpression of Grb10 in POMC neurons exacerbates or attenuates diet-induced obesity, respectively. Consistent with its role in leptin signalling, Grb10 in AgRP and POMC neurons enhances the anorexic and weight-reducing actions of leptin. Grb10 also exaggerates the inhibitory effects of leptin on AgRP neurons via ATP-sensitive potassium channel-mediated currents while facilitating the excitatory drive of leptin on POMC neurons through transient receptor potential channels. Our study identifies Grb10 as a potent leptin sensitizer that contributes to the maintenance of energy homeostasis by enhancing the response of AgRP and POMC neurons to leptin.


Asunto(s)
Leptina , Proopiomelanocortina , Ratones , Masculino , Femenino , Animales , Proteína Relacionada con Agouti/metabolismo , Leptina/metabolismo , Proopiomelanocortina/metabolismo , Proteína Adaptadora GRB10/metabolismo , Pérdida de Peso
10.
Front Plant Sci ; 14: 1335194, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38304454

RESUMEN

Introduction: In the actual planting of wheat, there are often shortages of seedlings and broken seedlings on long ridges in the field, thus affecting grain yield and indirectly causing economic losses. Variety identification of wheat seedlings using physical methods timeliness and is unsuitable for universal dissemination. Recognition of wheat seedling varieties using deep learning models has high timeliness and accuracy, but fewer researchers exist. Therefore, in this paper, a lightweight wheat seedling variety recognition model, MssiapNet, is proposed. Methods: The model is based on the MobileVit-XS and increases the model's sensitivity to subtle differences between different varieties by introducing the scSE attention mechanism in the MV2 module, so the recognition accuracy is improved. In addition, this paper proposes the IAP module to fuse the identified feature information. Subsequently, training was performed on a self-constructed real dataset, which included 29,020 photographs of wheat seedlings of 29 varieties. Results: The recognition accuracy of this model is 96.85%, which is higher than the other nine mainstream classification models. Although it is only 0.06 higher than the Resnet34 model, the number of parameters is only 1/3 of that. The number of parameters required for MssiapNet is 29.70MB, and the single image Execution time and the single image Delay time are 0.16s and 0.05s. The MssiapNet was visualized, and the heat map showed that the model was superior for wheat seedling variety identification compared with MobileVit-XS. Discussion: The proposed model has a good recognition effect on wheat seedling varieties and uses a few parameters with fast inference speed, which makes it easy to be subsequently deployed on mobile terminals for practical performance testing.

11.
Nat Med ; 28(12): 2537-2546, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36536256

RESUMEN

Serotonin reuptake inhibitors and receptor agonists are used to treat obesity, anxiety and depression. Here we studied the role of the serotonin 2C receptor (5-HT2CR) in weight regulation and behavior. Using exome sequencing of 2,548 people with severe obesity and 1,117 control individuals without obesity, we identified 13 rare variants in the gene encoding 5-HT2CR (HTR2C) in 19 unrelated people (3 males and 16 females). Eleven variants caused a loss of function in HEK293 cells. All people who carried variants had hyperphagia and some degree of maladaptive behavior. Knock-in male mice harboring a human loss-of-function HTR2C variant developed obesity and reduced social exploratory behavior; female mice heterozygous for the same variant showed similar deficits with reduced severity. Using the 5-HT2CR agonist lorcaserin, we found that depolarization of appetite-suppressing proopiomelanocortin neurons was impaired in knock-in mice. In conclusion, we demonstrate that 5-HT2CR is involved in the regulation of human appetite, weight and behavior. Our findings suggest that melanocortin receptor agonists might be effective in treating severe obesity in individuals carrying HTR2C variants. We suggest that HTR2C should be included in diagnostic gene panels for severe childhood-onset obesity.


Asunto(s)
Obesidad Mórbida , Receptor de Serotonina 5-HT2C , Animales , Niño , Femenino , Humanos , Masculino , Ratones , Células HEK293 , Obesidad/genética , Receptor de Serotonina 5-HT2C/genética , Serotonina , Agonistas del Receptor de Serotonina 5-HT2/farmacología , Adaptación Psicológica
12.
Cell Biosci ; 12(1): 170, 2022 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-36210455

RESUMEN

BACKGROUND: Pro-opiomelanocortin (POMC) neurons play a sexually dimorphic role in body weight and glucose balance. However, the mechanisms for the sex differences in POMC neuron functions are not fully understood. RESULTS: We detected small conductance calcium-activated potassium (SK) current in POMC neurons. Secondary analysis of published single-cell RNA-Seq data showed that POMC neurons abundantly express SK3, one SK channel subunit. To test whether SK3 in POMC neurons regulates POMC neuron functions on energy and glucose homeostasis, we used a Cre-loxP strategy to delete SK3 specifically from mature POMC neurons. POMC-specific deletion of SK3 did not affect body weight in either male or female mice. Interestingly, male mutant mice showed not only decreased food intake but also decreased physical activity, resulting in unchanged body weight. Further, POMC-specific SK3 deficiency impaired glucose balance specifically in female mice but not in male mice. Finally, no sex differences were detected in the expression of SK3 and SK current in total POMC neurons. However, we found higher SK current but lower SK3 positive neuron population in male POMC neurons co-expressing estrogen receptor α (ERα) compared to that in females. CONCLUSION: These results revealed a sexually dimorphic role of SK3 in POMC neurons in both energy and glucose homeostasis independent of body weight control, which was associated with the sex difference of SK current in a subpopulation of POMC + ERα + neurons.

13.
Front Endocrinol (Lausanne) ; 13: 889122, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36120438

RESUMEN

Pro-opiomelanocortin (POMC) neurons are important for the regulation of body weight and glucose balance. The inhibitory tone to POMC neurons is mediated primarily by the GABA receptors. However, the detailed mechanisms and functions of GABA receptors are not well understood. The α5 subunit of GABAA receptor, Gabra5, is reported to regulate feeding, and we found that Gabra5 is highly expressed in POMC neurons. To explore the function of Gabra5 in POMC neurons, we knocked down Gabra5 specifically from mature hypothalamic POMC neurons using the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 strategy. This POMC-specific knock-down of Gabra5 did not affect body weight or food intake in either male or female mice. Interestingly, the loss of Gabra5 caused significant increases in the firing frequency and resting membrane potential, and a decrease in the amplitude of the miniature inhibitory postsynaptic current (mIPSC) in male POMC neurons. However, the loss of Gabra5 only modestly decreased the frequency of mIPSC in female POMC neurons. Consistently, POMC-specific knock-down of Gabra5 significantly improved glucose tolerance in male mice but not in female mice. These results revealed a sexually dimorphic role of Gabra5 in POMC neuron activity and glucose balance, independent of body weight control.


Asunto(s)
Glucosa , Proopiomelanocortina , Animales , Peso Corporal , Femenino , Masculino , Ratones , Ratones Transgénicos , Neuronas/metabolismo , Proopiomelanocortina/genética , Receptores de GABA-A
15.
Nat Neurosci ; 25(5): 646-658, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35501380

RESUMEN

Midbrain dopamine (DA) and serotonin (5-HT) neurons regulate motivated behaviors, including feeding, but less is known about how these circuits may interact. In this study, we found that DA neurons in the mouse ventral tegmental area bidirectionally regulate the activity of 5-HT neurons in the dorsal raphe nucleus (DRN), with weaker stimulation causing DRD2-dependent inhibition and overeating, while stronger stimulation causing DRD1-dependent activation and anorexia. Furthermore, in the activity-based anorexia (ABA) paradigm, which is a mouse model mimicking some clinical features of human anorexia nervosa (AN), we observed a DRD2 to DRD1 shift of DA neurotransmission on 5-HTDRN neurons, which causes constant activation of these neurons and contributes to AN-like behaviors. Finally, we found that systemic administration of a DRD1 antagonist can prevent anorexia and weight loss in ABA. Our results revealed regulation of feeding behavior by stimulation strength-dependent interactions between DA and 5-HT neurons, which may contribute to the pathophysiology of AN.


Asunto(s)
Dopamina , Serotonina , Animales , Anorexia , Neuronas Dopaminérgicas , Mesencéfalo , Ratones , Neuronas/fisiología
16.
Front Physiol ; 12: 714104, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34393830

RESUMEN

Perineuronal nets (PNNs) are widely present in the hypothalamus, and are thought to provide physical protection and ion buffering for neurons and regulate their synaptic plasticity and intracellular signaling. Recent evidence indicates that PNNs in the mediobasal hypothalamus play an important role in the regulation of glucose homeostasis. However, whether and how hypothalamic PNNs are regulated are not fully understood. In the present study, we examined whether PNNs in various hypothalamic regions in mice can be regulated by sex, gonadal hormones, dietary interventions, or their interactions. We demonstrated that gonadal hormones are required to maintain normal PNNs in the arcuate nucleus of hypothalamus in both male and female mice. In addition, PNNs in the terete hypothalamic nucleus display a sexual dimorphism with females higher than males, and high-fat diet feeding increases terete PNNs only in female mice but not in male mice. On the other hand, PNNs in other hypothalamic regions are not influenced by sex, gonadal hormones or dietary interventions. In summary, we demonstrated that hypothalamic PNNs are regulated in a region-specific manner and these results provide a framework to further investigate the potential functions of PNNs in regulating energy/glucose homeostasis at the interplay of sex, gonadal hormones and diets.

17.
MAbs ; 12(1): 1836714, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33151102

RESUMEN

Activation of T cells specific for insulin B chain amino acids 9 to 23 (B:9-23) is essential for the initiation of type 1 diabetes (T1D) in non-obese diabetic mice. We previously reported that peptide/MHC complexes containing optimized B:9-23 mimotopes can activate most insulin-reactive pathogenic T cells. A monoclonal antibody (mAb287) targeting these complexes prevented disease in 30-50% of treated animals (compared to 10% of animals given an isotype control). The incomplete protection is likely due to the relatively low affinity of the antibody for its ligand and limited specificity. Here, we report an enhanced reagent, mAb757, with improved specificity, affinity, and efficacy in modulating T1D. Importantly, mAb757 bound with nanomolar affinity to agonists of both "type A" and "type B" cells and suppressed "type B" cells more efficiently than mAb287. When given weekly starting at 4 weeks of age, mAb757 protected ~70% of treated mice from developing T1D for at least 35 weeks, while mAb287 only delayed disease in 25% of animals under the same conditions. Consistent with its higher affinity, mAb757 was also able to stain antigen-presenting cells loaded with B:9-23 mimotopes in vivo. We conclude that monoclonal antibodies that can block the presentation of pathogenic T cell receptor epitopes are viable candidates for antigen-specific immunotherapy for T1D.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Linfocitos T CD4-Positivos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Epítopos de Linfocito T/inmunología , Insulina/inmunología , Fragmentos de Péptidos/inmunología , Animales , Afinidad de Anticuerpos/inmunología , Especificidad de Anticuerpos/inmunología , Autoantígenos/inmunología , Ligandos , Ratones , Ratones Endogámicos NOD
18.
J Vis Exp ; (150)2019 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-31475985

RESUMEN

Type 1 Diabetes (T1D) is characterized by islet-specific autoimmunity leading to beta cell destruction and absolute loss of insulin production. In the spontaneous non-obese diabetes (NOD) mouse model, insulin is the primary target, and genetic manipulation of these animals to remove a single key insulin epitope prevents disease. Thus, selective elimination of professional antigen presenting cells (APCs) bearing this pathogenic epitope is an approach to inhibit the unwanted insulin-specific autoimmune responses, and likely has greater translational potential. Chimeric antigen receptors (CARs) can redirect T cells to selectively target disease-causing antigens. This technique is fundamental to recent attempts to use cellular engineering for adoptive cell therapy to treat multiple cancers. In this protocol, we describe an optimized T-cell retrovirus (RV) transduction and in vitro expansion protocol that generates high numbers of functional antigen-specific CD8 CAR-T cells starting from a low number of naive cells. Previously multiple CAR-T cell protocols have been described, but typically with relatively low transduction efficiency and cell viability following transduction. In contrast, our protocol provides up to 90% transduction efficiency, and the cells generated can survive more than two weeks in vivo and significantly delay disease onset following a single infusion. We provide a detailed description of the cell maintenance and transduction protocol, so that the critical steps can be easily followed. The whole procedure from primary cell isolation to CAR expression can be performed within 14 days. The general method may be applied to any mouse disease model in which the target is known. Similarly, the specific application (targeting a pathogenic peptide/MHC class II complex) is applicable to any other autoimmune disease model for which a key complex has been identified.


Asunto(s)
Antígenos/fisiología , Diabetes Mellitus Tipo 1/inmunología , Linfocitos T Citotóxicos/fisiología , Animales , Células Presentadoras de Antígenos/inmunología , Autoinmunidad , Epítopos , Humanos , Inmunoterapia Adoptiva/métodos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Ratones , Ratones Endogámicos NOD
19.
PLoS One ; 10(9): e0137583, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26335571

RESUMEN

BACKGROUND: Growing evidence indicates that oxidative stress (OS), a persistent state of excess amounts of reactive oxygen species (ROS) along with reactive nitrogen species (RNS), plays an important role in insulin resistance, diabetic complications, and dysfunction of pancreatic ß-cells. Pancreatic ß-cells contain exceptionally low levels of antioxidant enzymes, rendering them susceptible to ROS-induced damage. Induction of antioxidants has been proposed to be a way for protecting ß-cells against oxidative stress. Compared to other antioxidants that act against particular ß-cell damages, metallothionein (MT) is the most effective in protecting ß-cells from several oxidative stressors including nitric oxide, peroxynitrite, hydrogen peroxide, superoxide and streptozotocin (STZ). We hypothesized that MT overexpression in pancreatic ß-cells would preserve ß-cell function in C57BL/6J mice, an animal model susceptible to high fat diet-induced obesity and type 2 diabetes. RESEARCH DESIGN AND METHODS: The pancreatic ß-cell specific MT overexpression was transferred to C57BL/6J background by backcrossing. We studied transgenic MT (MT-tg) mice and wild-type (WT) littermates at 8 weeks and 18 weeks of age. Several tests were performed to evaluate the function of islets, including STZ in vivo treatment, intraperitoneal glucose tolerance tests (IPGTT) and plasma insulin levels during IPGTT, pancreatic and islet insulin content measurement, insulin secretion, and islet morphology assessment. Gene expression in islets was performed by quantitative real-time PCR and PCR array analysis. Protein levels in pancreatic sections were evaluated by using immunohistochemistry. RESULTS: The transgenic MT protein was highly expressed in pancreatic islets. MT-tg overexpression significantly protected mice from acute STZ-induced ROS at 8 weeks of age; unexpectedly, however, MT-tg impaired glucose stimulated insulin secretion (GSIS) and promoted the development of diabetes. Pancreatic ß-cell function was significantly impaired, and islet morphology was also abnormal in MT-tg mice, and more severe damage was detected in males. The unique gene expression pattern and abnormal protein levels were observed in MT-tg islets. CONCLUSIONS: MT overexpression protected ß-cells from acute STZ-induced ROS damages at young age, whereas it impaired GSIS and promoted the development of diabetes in adult C57BL/6J mice, and more severe damage was found in males.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Células Secretoras de Insulina/metabolismo , Metalotioneína/metabolismo , Estrés Oxidativo/fisiología , Factores de Edad , Animales , Diabetes Mellitus Experimental/genética , Femenino , Prueba de Tolerancia a la Glucosa , Insulina/sangre , Masculino , Metalotioneína/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Especies Reactivas de Oxígeno/metabolismo , Factores Sexuales
20.
Zhongguo Zhen Jiu ; 35(3): 253-6, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26062197

RESUMEN

Taken Huantiao (GB 30) as breakthrough point, acupuncture manipulations of generating various needling sensations by different physicians are sorted. Types of acupoint needling sensations and conducting directions after acupuncture and all kinds of factors that affect needling sensations are analyzed from new perspectives. It is considered that attention should be paid to acupoint location, postures of patients, manipulation methods, types of needling sensations, transmission lines and duration time of needling sensations, etc.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura/instrumentación , Sensación , Terapia por Acupuntura/métodos , Humanos , Agujas
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