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1.
J Nepal Health Res Counc ; 21(1): 50-56, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37742149

RESUMO

BACKGROUND: Surgical site infection is one of the common complication following abdominal surgery. It causes great morbidity and mortality, further increasing prevalence of multidrug resistant bacteria have made its management very challenging. The current study aims to identify causative agent responsible for surgical site infection and their antibiotic resistance patterns. METHODS: This study was conducted among patients developing surgical site infection following gastrointestinal surgery in Tribhuvan university teaching hospital over a period of one year. The samples were collected and processed according to standard methods. The bacterial pathogens with their antimicrobial susceptibility were determined and resistant pattern like methicillin resistant Staphylococcus aureus and extended spectrum beta lactamase were further detected. RESULTS: A total of 832 patients had under gone gastrointestinal surgery during the study period. Among them, 162 cases (19.5%) developed surgical site infection and 125 cases showed growth in culture. A total of 160 aerobic bacteria were isolated; Escherichia coli (29.9%) was the commonest organism with 40.8% being extended spectrum beta lactamase producer and 47.4% of Staphylococcus aureus were methicillin resistant. About 75.9% (85/112) of gram negative bacteria and 60.4% (29/48) gram positive bacteria were multi drug resistant. CONCLUSIONS: The burden of multi drug resistant bacteria causing surgical site infection is high which needs to be addressed timely. Good surveillance of bacterial antibiogram and rational antimicrobial use is necessary to reduce emergence and spread of resistant bacteria.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Staphylococcus aureus Resistente à Meticilina , Humanos , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/epidemiologia , Nepal/epidemiologia , Testes de Sensibilidade Microbiana , Escherichia coli , beta-Lactamases
2.
JCI Insight ; 8(17)2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37535424

RESUMO

The growth of skeletal muscle relies on a delicate equilibrium between protein synthesis and degradation; however, how proteostasis is managed in the endoplasmic reticulum (ER) is largely unknown. Here, we report that the SEL1L-HRD1 ER-associated degradation (ERAD) complex, the primary molecular machinery that degrades misfolded proteins in the ER, is vital to maintain postnatal muscle growth and systemic energy balance. Myocyte-specific SEL1L deletion blunts the hypertrophic phase of muscle growth, resulting in a net zero gain of muscle mass during this developmental period and a 30% reduction in overall body growth. In addition, myocyte-specific SEL1L deletion triggered a systemic reprogramming of metabolism characterized by improved glucose sensitivity, enhanced beigeing of adipocytes, and resistance to diet-induced obesity. These effects were partially mediated by the upregulation of the myokine FGF21. These findings highlight the pivotal role of SEL1L-HRD1 ERAD activity in skeletal myocytes for postnatal muscle growth, and its physiological integration in maintaining whole-body energy balance.


Assuntos
Degradação Associada com o Retículo Endoplasmático , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Proteínas/genética , Músculos/metabolismo , Metabolismo Energético , Hipertrofia/metabolismo
3.
J Am Coll Health ; : 1-7, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37437177

RESUMO

Objective: Empathic concern (EC) for others may be related to COVID-19 pandemic responses. Participants and methods: The purpose of this survey study was to examine differences in pandemic responses in 1,778 college students rated as low (LE) versus high (HE) on the EC subscale of the Interpersonal Reactivity Index. Results: HE participants reported greater concerns in numerous pandemic-related domains, including acquiring COVID-19; access to COVID-19 treatment; number of COVID-19 cases, hospitalizations, and deaths reported; staying employed; and being isolated for long periods of time. Generalized anxiety symptoms, depressive symptoms, and perceived stress scores were significantly higher for individuals in the HE group compared to the LE group. The HE group reported being significantly more adherent to health and safety recommendations than the LE group. Conclusions: Empathic concern for others is important for promoting college student prosocial behavior but is associated with anxiety and depression symptomatology during times of traumatic stress.

4.
Int J Mol Sci ; 24(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298359

RESUMO

Oral cancer is primarily squamous-cell carcinoma with a 5-year survival rate of approximately 50%. Lysyl oxidase (LOX) participates in collagen and elastin maturation. The propeptide of LOX is released as an 18 kDa protein (LOX-PP) in the extracellular environment by procollagen C-proteinases and has tumor-inhibitory properties. A polymorphism in the propeptide region of LOX (rs1800449, G473A) results in a single amino acid substitution of Gln for Arg. Here we investigated the frequency of rs1800449 in OSCC employing TCGA database resources and determined the kinetics and severity of precancerous oral lesion development in wildtype and corresponding knockin mice after exposure to 4-nitroquinoline oxide (4 NQO) in drinking water. Data show that the OSCC is more common in humans carrying the variant compared to the wildtype. Knockin mice are more susceptible to lesion development. The immunohistochemistry of LOX in mouse tissues and in vitro studies point to a negative feedback pathway of wildtype LOX-PP on LOX expression that is deficient in knockin mice. Data further demonstrate modulations of T cell phenotype in knockin mice toward a more tumor-permissive condition. Data provide initial evidence for rs1800449 as an oral cancer susceptibility biomarker and point to opportunities to better understand the functional mechanism of LOX-PP cancer inhibitory activity.


Assuntos
Neoplasias Bucais , Proteína-Lisina 6-Oxidase , Animais , Humanos , Camundongos , Carcinógenos , Colágeno/genética , Neoplasias Bucais/genética , Polimorfismo Genético , Proteína-Lisina 6-Oxidase/metabolismo
5.
Subst Use Misuse ; 58(10): 1177-1186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37259841

RESUMO

BACKGROUND: This study examined changes in reported alcohol use among women during the early stages of the COVID-19 pandemic and the relations to adverse changes in employment (e.g. job loss, furlough, reduced pay). Further, this study assessed how the relation between changes in alcohol use and experiencing an adverse change in employment was moderated by four theoretically relevant dimensions of conformity to masculine norms (CMNI, i.e. risk-taking, winning, self-reliance, and primacy of work). METHODS: The sample for the present study is a subset of a survey that was conducted in the spring of 2020 among U.S. adults and includes 509 participants who met the inclusion criteria. We assessed pandemic-related employment change status, changes in reported frequency and quantity of alcohol consumed, and four CMNI dimensions. Relations between these variables were assessed with a multinomial logistic regression path model. RESULTS: Experiencing an adverse change in employment early in the pandemic was related to increased alcohol use when moderated by the CMNI dimension primacy of work. For people higher on primacy of work, an adverse change in employment was associated with a higher likelihood of reporting an increase in frequency, but not quantity, of drinking (rather than a decrease or no change). Not experiencing an adverse change in employment early in the pandemic was associated with an increased likelihood of reporting an increase for quantity but not frequency. CONCLUSION: The results highlight the importance of considering how work-oriented women may be at risk for increasing alcohol use when confronted with changes in work status.


Assuntos
COVID-19 , Pandemias , Adulto , Humanos , Feminino , Comportamento Social , Emprego , Consumo de Bebidas Alcoólicas/epidemiologia
6.
Polymers (Basel) ; 15(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36904404

RESUMO

Self-assembly is a growth mechanism in nature to apply local interactions forming a minimum energy structure. Currently, self-assembled materials are considered for biomedical applications due to their pleasant features, including scalability, versatility, simplicity, and inexpensiveness. Self-assembled peptides can be applied to design and fabricate different structures, such as micelles, hydrogels, and vesicles, by diverse physical interactions between specific building blocks. Among them, bioactivity, biocompatibility, and biodegradability of peptide hydrogels have introduced them as versatile platforms in biomedical applications, such as drug delivery, tissue engineering, biosensing, and treating different diseases. Moreover, peptides are capable of mimicking the microenvironment of natural tissues and responding to internal and external stimuli for triggered drug release. In the current review, the unique characteristics of peptide hydrogels and recent advances in their design, fabrication, as well as chemical, physical, and biological properties are presented. Additionally, recent developments of these biomaterials are discussed with a particular focus on their biomedical applications in targeted drug delivery and gene delivery, stem cell therapy, cancer therapy and immune regulation, bioimaging, and regenerative medicine.

7.
J Adult Dev ; : 1-12, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36811122

RESUMO

The purpose of this study was to assess differences in mental health symptoms, pandemic-related concerns, and maladaptive coping behaviors among adults in the United States across generations during the initial period of the COVID-19 pandemic. A social media campaign was used to recruit 2696 U.S. individuals to participate in an online survey in April 2020, assessing various validated psychosocial factors, including major depressive disorder, generalized anxiety disorder (GAD), perceived stress, loneliness, quality of life, and fatigue, along with pandemic-specific concerns and changes in alcohol use and substance use. Participants were grouped based on generation status (Gen Z, Millennial, Gen X, and Baby Boomer) and statistical comparisons were conducted based on demographics, psychosocial factors, pandemic-related concerns, and substance use. During the initial period of the COVID-19 pandemic, the younger cohorts (Gen Z and Millennials) rated significantly worse on mental health indices, including major depression, GAD, perceived stress, loneliness, quality of life, and fatigue. Further, the participants in the Gen Z and Millennial generational groups exhibited greater increase in maladaptive coping with substance use, specifically alcohol use and increased use of sleep aids. Our results indicate that during the initial period of the COVID-19 pandemic, members of the Gen Z and Millennial generational cohorts were considered a psychologically vulnerable population due to their mental health and maladaptive coping behaviors. Improving access to mental health resources during early stages of a pandemic is an emerging public health concern.

8.
J Clin Invest ; 133(1)2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36346671

RESUMO

Three principal ER quality-control mechanisms, namely, the unfolded protein response, ER-associated degradation (ERAD), and ER-phagy are each important for the maintenance of ER homeostasis, yet how they are integrated to regulate ER homeostasis and organellar architecture in vivo is largely unclear. Here we report intricate crosstalk among the 3 pathways, centered around the SEL1L-HRD1 protein complex of ERAD, in the regulation of organellar organization in ß cells. SEL1L-HRD1 ERAD deficiency in ß cells triggers activation of autophagy, at least in part, via IRE1α (an endogenous ERAD substrate). In the absence of functional SEL1L-HRD1 ERAD, proinsulin is retained in the ER as high molecular weight conformers, which are subsequently cleared via ER-phagy. A combined loss of both SEL1L and autophagy in ß cells leads to diabetes in mice shortly after weaning, with premature death by approximately 11 weeks of age, associated with marked ER retention of proinsulin and ß cell loss. Using focused ion beam scanning electron microscopy powered by deep-learning automated image segmentation and 3D reconstruction, our data demonstrate a profound organellar restructuring with a massive expansion of ER volume and network in ß cells lacking both SEL1L and autophagy. These data reveal at an unprecedented detail the intimate crosstalk among the 3 ER quality-control mechanisms in the dynamic regulation of organellar architecture and ß cell function.


Assuntos
Degradação Associada com o Retículo Endoplasmático , Endorribonucleases , Camundongos , Animais , Endorribonucleases/metabolismo , Proinsulina/genética , Proinsulina/metabolismo , Ubiquitina-Proteína Ligases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas/metabolismo
9.
J Am Coll Health ; : 1-8, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36170460

RESUMO

Objective: This study examined acculturation with positive alcohol expectancies (PAE) and alcohol use intentions among college-bound Latinas using a bidimensional (ie U.S. acculturation/enculturation) and bidomain (ie behaviors/values) acculturation framework. Participants: A total of 298 Latina young adults between 18 and 20 years old were included in this analysis. Methods: Data were collected the summer before participants began college for the first time. We used an online survey to assess acculturation, PAE, and alcohol use expectancies. Results: Path analyses showed that U.S. acculturation values were related to more PAE and alcohol use intentions. U.S. acculturation behaviors were related to more alcohol use intentions, and the pathway was moderated by PAE. There was also an interaction between U.S. acculturation and enculturation behaviors predicting alcohol use intentions. Conclusion: This study sheds light on how acculturating Latina young women think about alcohol use prior to beginning college, which is an opportune window for targeted prevention programs.

10.
Acta Biomater ; 140: 561-572, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34923097

RESUMO

Nanoparticle-based oral drug delivery systems have the potential to target inflamed regions in the gastrointestinal tract by specifically accumulating at disrupted colonic epithelium. But, delivery of intact protein drugs at the targeted site is a major challenge due to the harsh gastrointestinal environment and the protective mucus layer. Biocompatible nanoparticles engineered to target the inflamed colonic tissue and efficiently penetrate the mucosal layer can provide a promising approach for orally delivering monoclonal antibodies to treat inflammatory bowel disease. The study aims to develop mucus-penetrating nanoparticles composed of poly(lactic-co-glycolic acid, PLGA) polymers with two different polyethylene glycol (PEG) chain lengths (2 kDa and 5kDa) to encapsulate monoclonal antibody against tumor necrosis factor-α (TNF-α). The impact of different PEG chain lengths on the efficacy of the nanosystems was evaluated in vitro, ex vivo, and in vivo. Both PLGA-PEG2k and PLGA-PEG5k nanoparticles successfully encapsulated the antibody and significantly reduced TNF-α secretion from activated macrophages and intestinal epithelial cells. However, only antibody-loaded PLGA-PEG2k nanoparticles were able to alleviate the experimental acute colitis in mice demonstrated by improved colon weight/length ratio, histological score, and reduced tissue-associated myeloperoxidase activity and expression of proinflammatory cytokine TNF-α levels compared with the control group. The results suggest that despite having no significant differences in the in vitro cell-based assays, PEG chain length has a significant impact on the in vivo performance of the mucus penetrating nanoparticles. Overall, PLGA-PEG2k nanoparticles were presented as a promising oral delivery system for targeted antibody delivery to treat inflammatory bowel disease. STATEMENT OF SIGNIFICANCE: There is an unmet therapeutic need for oral drug delivery systems for safe and effective antibody therapy of inflammatory bowel disease. Therefore, we have developed PEGylated PLGA-based nanoparticulate drug delivery systems for oral targeted delivery of anti-TNF-α antibody as a potential alternative treatment strategy. The PEG chain length did not affect encapsulation efficiency or interaction with mucin in vitro but resulted in differences in in vitro release profile and in vivo efficacy study. We demonstrated the superiority of anti-TNF-α mAb-PLGA-PEG2k over mAb-PLGA-PEG5k nanoparticles to effectively exhibit anti-inflammatory responses in an acute murine colitis model. These nanoparticle-based formulations may be adjusted to encapsulate other drugs that could be applied to a number of disorders at different mucosal surfaces.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Nanopartículas , Animais , Colite/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Camundongos , Sistemas de Liberação de Fármacos por Nanopartículas , Polietilenoglicóis/metabolismo , Inibidores do Fator de Necrose Tumoral
11.
Front Endocrinol (Lausanne) ; 12: 650158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967960

RESUMO

The notion that in diabetes pancreatic ß-cells express endoplasmic reticulum (ER) stress markers indicative of increased unfolded protein response (UPR) signaling is no longer in doubt. However, what remains controversial is whether this increase in ER stress response actually contributes importantly to the ß-cell failure of type 2 diabetes (akin to 'terminal UPR'), or whether it represents a coping mechanism that represents the best attempt of ß-cells to adapt to changes in metabolic demands as presented by disease progression. Here an intercontinental group of experts review evidence for the role of ER stress in monogenic and type 2 diabetes in an attempt to reconcile these disparate views. Current evidence implies that pancreatic ß-cells require a regulated UPR for their development, function and survival, as well as to maintain cellular homeostasis in response to protein misfolding stress. Prolonged ER stress signaling, however, can be detrimental to ß-cells, highlighting the importance of "optimal" UPR for ER homeostasis, ß-cell function and survival.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Estresse do Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Endorribonucleases/metabolismo , Regulação da Expressão Gênica , Células Secretoras de Insulina/citologia , Proteínas Serina-Treonina Quinases/metabolismo , Resposta a Proteínas não Dobradas/fisiologia , Animais , Sobrevivência Celular , Estudo de Associação Genômica Ampla , Homeostase , Humanos , Camundongos , Fenótipo , Desnaturação Proteica , Dobramento de Proteína , Transporte Proteico , RNA Mensageiro/metabolismo , Transdução de Sinais
12.
Adv Drug Deliv Rev ; 175: 113795, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33989702

RESUMO

Oral administration is the most commonly used route for drug delivery owing to its cost-effectiveness, ease of administration, and high patient compliance. However, the absorption of orally delivered compounds is a complex process that greatly depends on the interplay between the characteristics of the drug/formulation and the gastrointestinal tract. In this contribution, we review the different preclinical models (in vitro, ex vivo and in vivo) from their development to application for studying the transport of drugs across intestinal barriers. This review also discusses the advantages and disadvantages of each model. Furthermore, the authors have reviewed the selection and validation of these models and how the limitations of the models can be addressed in future investigations. The correlation and predictability of the intestinal transport data from the preclinical models and human data are also explored. With the increasing popularity and prevalence of orally delivered drugs/formulations, sophisticated preclinical models with higher predictive capacity for absorption of oral formulations used in clinical studies will be needed.


Assuntos
Absorção Intestinal , Mucosa Intestinal/metabolismo , Administração Oral , Animais , Humanos , Farmacocinética
14.
Drug Deliv Transl Res ; 11(2): 524-545, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33575972

RESUMO

The potential of nanoemulsions for the oral administration of peptides is still in its early stage. The aim of the present work was to rationally design, develop, and fully characterize a new nanoemulsion (NE) intended for the oral administration of hydrophobically modified insulin (HM-insulin). Specific components of the NE were selected based on their enhancing permeation properties as well as their ability to improve insulin association efficiency (Miglyol 812, sodium taurocholate), stability in the intestinal fluids, and mucodiffusion (PEGylated phospholipids and poloxamer 407). The results showed that the NE co-existed with a population of micelles, forming a mixed system that exhibited a 100% of HM-insulin association efficiency. The nanosystem showed good stability and miscibility in different bio-relevant media and displayed an acceptable mucodiffusive behavior in porcine mucus. In addition, it exhibited a high interaction with cell mono-cultures (Caco -2 and C2BBe1 human colon carcinoma Caco-2 clone cells) and co-cultures (C2BBe1 human colon carcinoma Caco-2 clone/HT29-MTX cells). The internalization in Caco-2 monolayers was also confirmed by confocal microscopy. Finally, the promising in vitro behavior of the nanosystem in terms of overcoming the biological barriers of the intestinal tract was translated into a moderate, although significant, hypoglycemic response (≈ 20-30%), following intestinal administration to both healthy and diabetic rat models. Overall, this information underlines the crucial steps to address when designing peptide-based nanoformulations to successfully overcome the intestinal barriers associated to the oral modality of administration.


Assuntos
Insulina , Nanopartículas , Administração Oral , Animais , Células CACO-2 , Sistemas de Liberação de Medicamentos , Humanos , Micelas , Ratos , Suínos
15.
Semin Cell Dev Biol ; 103: 59-67, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32402517

RESUMO

Type 1 and type 2 diabetes are associated with loss of ß cell function. Optimal ß cell function is linked to protein homeostasis in the endoplasmic reticulum (ER). Here, we review the roles of ER protein quality-control mechanisms, including the unfolded protein response (UPR), autophagy (specifically ER-phagy) and ER-associated degradation (ERAD), in ß cells. We propose that different quality control mechanisms may control different aspects of ß cell biology (i.e. function, survival, and identity), thereby contributing to disease pathogenesis.


Assuntos
Diabetes Mellitus/metabolismo , Retículo Endoplasmático/metabolismo , Células Secretoras de Insulina/metabolismo , Proteínas de Membrana/metabolismo , Humanos
16.
J Mater Chem B ; 8(19): 4340-4356, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32363370

RESUMO

One of the long-standing challenges in materials science involves synthesizing biomaterials that recapitulate important features of native biological tissues. Even though, the number of available biomaterials at the moment are virtually limitless, few of them has unlocked all the secrets of the human body by mimicking the combinatorial-like material properties of our tissues and organs. Inspired by the human body, we have developed a polymeric gum, which combines stretchability, toughness, strength, flexibility, and self-healing. It also exhibits a high bioactivity that can target and eliminate bacterial infections fast and reliably. Notably, this material is moldable into almost any complex shape, and therefore suitable as a building block for wearables designed to conform directly with the curved and personalized anatomy of patients. It also exhibits excellent drug retention and release capacity, which altogether makes it suitable for applications in personalized wearable drug-delivery devices.


Assuntos
Materiais Biocompatíveis/farmacologia , Sistemas de Liberação de Medicamentos , Álcool de Polivinil/farmacologia , Taninos/farmacologia , Dispositivos Eletrônicos Vestíveis , Cicatrização/efeitos dos fármacos , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Humanos , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula , Álcool de Polivinil/síntese química , Álcool de Polivinil/química , Propriedades de Superfície , Taninos/síntese química , Taninos/química
17.
J Control Release ; 322: 486-508, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32276004

RESUMO

Oral drug administration is one of the most preferred and simplest routes among both patients and formulation scientists. Nevertheless, orally delivery of some of the most widely used therapeutic agents (e.g., anticancer drugs, peptides, proteins and vaccines) is still a major challenge due to the limited oral bioavailability associated with them. The poor oral bioavailability of such drugs is attributed to one or many factors, such as poor aqueous solubility, poor permeability, and enzymatic degradation. Various technological strategies (such as permeation enhancers, prodrugs and nanocarriers) have been developed to enhance the bioavailability of these drugs after oral administration. Among the different approaches, advanced and innovative drug delivery systems, especially targeting-based strategies, have garnered tremendous attention. Furthermore, the presence of numerous types of cells and solute carrier transporters throughout the gastrointestinal tract represents numerous potential targeting sites for successful oral delivery that have not yet been exploited for their full potential. This review describes different targeting strategies towards different targeting sites in the gastrointestinal tract. Additionally, exciting improvements in oral drug delivery systems with different targeting strategies (e.g., M cells for oral vaccination and L cells for type 2 diabetes mellitus) are also discussed.


Assuntos
Diabetes Mellitus Tipo 2 , Administração Oral , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Humanos , Solubilidade
18.
J Clin Invest ; 130(7): 3499-3510, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182217

RESUMO

ß Cell apoptosis and dedifferentiation are 2 hotly debated mechanisms underlying ß cell loss in type 2 diabetes; however, the molecular drivers underlying such events remain largely unclear. Here, we performed a side-by-side comparison of mice carrying ß cell-specific deletion of ER-associated degradation (ERAD) and autophagy. We reported that, while autophagy was necessary for ß cell survival, the highly conserved Sel1L-Hrd1 ERAD protein complex was required for the maintenance of ß cell maturation and identity. Using single-cell RNA-Seq, we demonstrated that Sel1L deficiency was not associated with ß cell loss, but rather loss of ß cell identity. Sel1L-Hrd1 ERAD controlled ß cell identity via TGF-ß signaling, in part by mediating the degradation of TGF-ß receptor 1. Inhibition of TGF-ß signaling in Sel1L-deficient ß cells augmented the expression of ß cell maturation markers and increased the total insulin content. Our data revealed distinct pathogenic effects of 2 major proteolytic pathways in ß cells, providing a framework for therapies targeting distinct mechanisms of protein quality control.


Assuntos
Retículo Endoplasmático , Células Secretoras de Insulina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas/metabolismo , Proteólise , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adulto , Idoso , Animais , Sobrevivência Celular/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Células HEK293 , Humanos , Células Secretoras de Insulina/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Proteínas/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Fator de Crescimento Transformador beta/genética , Ubiquitina-Proteína Ligases/genética
19.
Eur J Pharm Sci ; 137: 104967, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31252052

RESUMO

Poorly water-soluble drugs continue to be a problematic, yet important class of pharmaceutical compounds for treatment of a wide range of diseases. Their prevalence in discovery is still high, and their development is usually limited by our lack of a complete understanding of how the complex chemical, physiological and biochemical processes that occur between administration and absorption individually and together impact on bioavailability. This review defines the challenge presented by these drugs, outlines contemporary strategies to solve this challenge, and consequent in silico and in vitro evaluation of the delivery technologies for poorly water-soluble drugs. The next steps and unmet needs are proposed to present a roadmap for future studies for the field to consider enabling progress in delivery of poorly water-soluble compounds.


Assuntos
Sistemas de Liberação de Medicamentos , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Animais , Humanos , Preparações Farmacêuticas/química , Solubilidade , Água/química
20.
Nat Immunol ; 20(6): 677-686, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31110312

RESUMO

Consumption of a high-energy Western diet triggers mild adaptive ß cell proliferation to compensate for peripheral insulin resistance; however, the underlying molecular mechanism remains unclear. In the present study we show that the toll-like receptors TLR2 and TLR4 inhibited the diet-induced replication of ß cells in mice and humans. The combined, but not the individual, loss of TLR2 and TLR4 increased the replication of ß cells, but not that of α cells, leading to enlarged ß cell area and hyperinsulinemia in diet-induced obesity. Loss of TLR2 and TLR4 increased the nuclear abundance of the cell cycle regulators cyclin D2 and Cdk4 in a manner dependent on the signaling mediator Erk. These data reveal a regulatory mechanism controlling the proliferation of ß cells in diet-induced obesity and suggest that selective targeting of the TLR2/TLR4 pathways may reverse ß cell failure in patients with diabetes.


Assuntos
Células Secretoras de Insulina/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Animais , Proliferação de Células , Ciclina D2/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Insulina/sangue , Insulina/metabolismo , Células Secretoras de Insulina/ultraestrutura , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Knockout , Complexos Multiproteicos/metabolismo , Obesidade/tratamento farmacológico , Parabiose , Ligação Proteica , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
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