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BACKGROUND: End-stage renal disease (ESRD) is a growing cause of morbidity worldwide. Protein malnutrition is common among patients with ESRD. Peritoneal dialysis (PD) offers greater lifestyle flexibility and independence compared to the widely used treatments for ESRD. This study aimed to assess the nutritional status and the quality of life (QOL) of Palestinian patients undergoing PD, as well as the variables affecting these two outcomes. METHODS: A cross-sectional study was conducted on patients receiving PD at An-Najah National University Hospital, Palestine. The malnutrition-inflammation scale (MIS) was used to measure malnutrition, and the QOL score was evaluated using the Dutch WHOQOL-OLD module. Univariate and multivariate linear regressions were performed to check the association between the QOL and MIS scores. RESULTS: The study included 74 patients who were undergoing PD, with an average age of 50.5 ± 16.38. The majority of the patients were females. The study found a significant correlation between malnutrition and lower quality of life (QOL) scores, as measured by the WHOQOL-OLD questionnaire (p < 0.001). Furthermore, younger patients and those who had an occupation were more likely to report a good QOL (p = 0.01). Conversely, patients with pitting edema and diabetes were at higher risk of reporting a lower QOL (p < 0.001). CONCLUSIONS: Given the elevated risk of malnutrition and diminished QOL among elderly patients, those with pitting edema, and individuals with diabetes, it is imperative to conduct thorough assessments for these groups. We strongly recommend that general practitioners, dietitians, and specialists collaborate to develop tailored programs and interventions to provide these patients with the focused care and attention they require.
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Diabetes Mellitus , Falência Renal Crônica , Desnutrição , Diálise Peritoneal , Feminino , Humanos , Idoso , Adulto , Pessoa de Meia-Idade , Masculino , Estado Nutricional , Qualidade de Vida , Estudos Transversais , Diálise Renal , Árabes , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Inflamação , EdemaRESUMO
Achieving glycemic control and sustaining functional pancreatic ß-cell activity remains an unmet medical need in the treatment of type 2 diabetes mellitus (T2DM). Glucokinase activators (GKAs) constitute a class of anti-diabetic drugs designed to regulate blood sugar levels and enhance ß-cell function in patients with diabetes. A significant progression in GKA development is underway to address the limitations of earlier generations. Dorzagliatin, a dual-acting GKA, targets both the liver and pancreas and has successfully completed two phase III trials, demonstrating favorable results in diabetes treatment. The hepato-selective GKA, TTP399, emerges as a strong contender, displaying clinically noteworthy outcomes with minimal adverse effects. This paper seeks to review the current literature, delve into the mechanisms of action of these new-generation GKAs, and assess their efficacy and safety in treating T2DM based on published preclinical studies and recent clinical trials.
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Diabetes Mellitus Tipo 2 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucoquinase , Pâncreas , Controle GlicêmicoRESUMO
Nivolumab is used to treat several different types of cancers. Although it is generally considered to be effective and well-tolerated, it has been associated with adverse effects requiring discontinuation of treatment, like many other drugs used for cancer. A 70-year-old male was switched from sunitinib to nivolumab for renal cell carcinoma. The patient developed persistent hypothyroidism, onycholysis, and pneumonitis at nivolumab cycle 6, 10, and 11, respectively. Using the Naranjo causality method, the likelihood of causality was deemed "probable" for pneumonitis and hypothyroidism and "possible" for onycholysis. Nivolumab was eventually discontinued due to disease progression, rather than safety concerns. Eudravigilance, the European pharmacovigilance database, was searched for all nivolumab-related individual case safety reports from Malta, up to September 4, 2023. Six reports were identified in Malta, although the 3 events identified in this case report were not reported, suggesting under-reporting in Malta. This case report identified an uncommon nivolumab adverse drug reaction (ADR), onycholysis and showed how, despite the occurrence of 3 ADRs, it was its lack of efficacy rather than its safety which led to its discontinuation in this particular patient.
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Class switch recombination (CSR) plays an important role in adaptive immune response by enabling mature B cells to switch from IgM expression to the expression of downstream isotypes. CSR is preceded by inducible germline (GL) transcription of the constant genes and is controlled by the 3' regulatory region (3'RR) in a stimulus-dependent manner. Why the 3'RR-mediated up-regulation of GL transcription is delayed to the mature B-cell stage is presently unknown. Here we show that mice devoid of an inducible CTCF binding element, located in the α constant gene, display a marked isotype-specific increase of GL transcription in developing and resting splenic B cells and altered CSR in activated B cells. Moreover, insertion of a GL promoter downstream of the CTCF insulator led to premature activation of the ectopic promoter. This study provides functional evidence that the 3'RR has a developmentally controlled potential to constitutively activate GL promoters but that this activity is delayed, at least in part, by the CTCF insulator, which borders a transcriptionally active domain established by the 3'RR in developing B cells.
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Fator de Ligação a CCCTC/genética , Cadeias Pesadas de Imunoglobulinas/genética , Regiões 3' não Traduzidas , Animais , Linfócitos B/metabolismo , Sequência de Bases , Fator de Ligação a CCCTC/metabolismo , Feminino , Células Germinativas , Switching de Imunoglobulina/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Masculino , Camundongos , Camundongos da Linhagem 129 , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Transcrição Gênica , Regulação para CimaRESUMO
Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) are a valuable tool in stem cell research due to their high proliferation rate, multi-lineage differentiation potential, and immunotolerance properties. However, fibroblast impurity during WJ-MSCs isolation is unavoidable because of morphological similarities and shared surface markers. Here, a proteomic approach was employed to identify specific proteins differentially expressed by WJ-MSCs in comparison to those by neonatal foreskin and adult skin fibroblasts (NFFs and ASFs, respectively). Mass spectrometry analysis identified 454 proteins with a transmembrane domain. These proteins were then compared across the different cell-lines and categorized based on their cellular localizations, biological processes, and molecular functions. The expression patterns of a selected set of proteins were further confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting, and immunofluorescence assays. As anticipated, most of the studied proteins had common expression patterns. However, EphA2, SLC25A4, and SOD2 were predominantly expressed by WJ-MSCs, while CDH2 and Talin2 were specific to NFFs and ASFs, respectively. Here, EphA2 was established as a potential surface-specific marker to distinguish WJ-MSCs from fibroblasts and for prospective use to prepare pure primary cultures of WJ-MSCs. Additionally, CDH2 could be used for a negative-selection isolation/depletion method to remove neonatal fibroblasts contaminating preparations of WJ-MSCs.
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Efrina-A2/metabolismo , Fibroblastos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Proteoma/análise , Proteoma/metabolismo , Pele/metabolismo , Geleia de Wharton/metabolismo , Biomarcadores , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Fibroblastos/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Receptor EphA2 , Pele/citologia , Geleia de Wharton/citologiaRESUMO
Class switch recombination (CSR) occurs between highly repetitive sequences called switch (S) regions and is initiated by activation-induced cytidine deaminase (AID). CSR is preceded by a bidirectional transcription of S regions but the relative importance of sense and antisense transcription for CSR in vivo is unknown. We generated three mouse lines in which we attempted a premature termination of transcriptional elongation by inserting bidirectional transcription terminators upstream of Sµ, upstream of Sγ3 or downstream of Sγ3 sequences. The data show, at least for Sγ3, that sense transcriptional elongation across S region is absolutely required for CSR whereas its antisense counterpart is largely dispensable, strongly suggesting that sense transcription is sufficient for AID targeting to both DNA strands.
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Citidina Desaminase/genética , DNA Antissenso/genética , Switching de Imunoglobulina/genética , Região de Troca de Imunoglobulinas/genética , Recombinação Genética , Transcrição Gênica , Animais , Linfócitos B/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunoglobulinas/genética , Camundongos , Poliadenilação , Reação em Cadeia da PolimeraseRESUMO
Germinal centers (GCs) are clusters of activated B cells that form in secondary lymphoid organs during a T-dependent immune response. B cells enter GCs and become rapidly proliferating centroblasts that express the enzyme activation-induced deaminase (AID) to undergo somatic hypermutation and class-switch recombination. Centroblasts then mature into centrocytes to undergo clonal selection. Within the GC, the highest affinity B cell clones are selected to mature into memory or plasma cells while lower affinity clones undergo apoptosis. We reported previously that murine Aicda(-/-) GC B cells have enhanced viability and accumulate in GCs. We now show that murine Aicda(-/-) GC B cells accumulate as centrocytes and inefficiently generate plasma cells. The reduced rate of plasma cell formation was not due to an absence of AID-induced DNA lesions. In addition, we show that the deletion of caspase 8 specifically in murine GC-B cells results in larger GCs and a delay in affinity maturation, demonstrating the importance of apoptosis in GC homeostasis and clonal selection.
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Apoptose/fisiologia , Síndrome Linfoproliferativa Autoimune/imunologia , Subpopulações de Linfócitos B/imunologia , Caspase 8/fisiologia , Seleção Clonal Mediada por Antígeno , Citidina Desaminase/fisiologia , Centro Germinativo/imunologia , Síndromes de Imunodeficiência/patologia , Transferência Adotiva , Animais , Antígenos/imunologia , Subpopulações de Linfócitos B/patologia , Caspase 8/genética , Divisão Celular , Citidina Desaminase/deficiência , Citidina Desaminase/genética , Quebras de DNA de Cadeia Dupla , Centro Germinativo/patologia , Imunização , Switching de Imunoglobulina , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmócitos/patologia , Quimera por Radiação , Receptores de Antígenos de Linfócitos B/imunologia , Hipermutação Somática de ImunoglobulinaRESUMO
Upon activation with T-dependent Ag, B cells enter germinal centers (GC) and upregulate activation-induced deaminase (AID). AID(+) GC B cells then undergo class-switch recombination and somatic hypermutation. Follicular dendritic cells (FDC) are stromal cells that underpin GC and require constitutive signaling through the lymphotoxin (LT) ß receptor to be maintained in a fully mature, differentiated state. Although it was shown that FDC can be dispensable for the generation of affinity-matured Ab, in the absence of FDC it is unclear where AID expression occurs. In a mouse model that lacks mature FDC, as well as other LT-sensitive cells, we show that clusters of AID(+)PNA(+)GL7(+) Ag-specific GC B cells form within the B cell follicles of draining lymph nodes, suggesting that FDC are not strictly required for GC formation. However, later in the primary response, FDC-less GC dissipated prematurely, correlating with impaired affinity maturation. We examined whether GC dissipation was due to a lack of FDC or other LTß receptor-dependent accessory cells and found that, in response to nonreplicating protein Ag, FDC proved to be more critical for long-term GC maintenance. Our study provides a spatial-temporal analysis of Ag-specific B cell activation and AID expression in the context of a peripheral lymph node that lacks FDC-M1(+) CD35(+) FDC and other LT-sensitive cell types, and reveals that FDC are not strictly required for the induction of AID within an organized GC-like environment.
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Linfócitos B/imunologia , Citidina Desaminase/metabolismo , Células Dendríticas Foliculares/metabolismo , Centro Germinativo/citologia , Animais , Diferenciação Celular , Células Cultivadas , Citidina Desaminase/biossíntese , Células Dendríticas Foliculares/citologia , Células Dendríticas Foliculares/imunologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Linfonodos/imunologia , Ativação Linfocitária/imunologia , Receptor beta de Linfotoxina/imunologia , Receptor beta de Linfotoxina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Complemento 3b/metabolismoRESUMO
Dysregulated metabolic dynamics are evident in both cancer and diabetes, with metabolic alterations representing a facet of the myriad changes observed in these conditions. This review delves into the commonalities in metabolism between cancer and type 2 diabetes (T2D), focusing specifically on the contrasting roles of oxidative phosphorylation (OXPHOS) and glycolysis as primary energy-generating pathways within cells. Building on earlier research, we explore how a shift towards one pathway over the other serves as a foundational aspect in the development of cancer and T2D. Unlike previous reviews, we posit that this shift may occur in seemingly opposing yet complementary directions, akin to the Yin and Yang concept. These metabolic fluctuations reveal an intricate network of underlying defective signaling pathways, orchestrating the pathogenesis and progression of each disease. The Warburg phenomenon, characterized by the prevalence of aerobic glycolysis over minimal to no OXPHOS, emerges as the predominant metabolic phenotype in cancer. Conversely, in T2D, the prevailing metabolic paradigm has traditionally been perceived in terms of discrete irregularities rather than an OXPHOS-to-glycolysis shift. Throughout T2D pathogenesis, OXPHOS remains consistently heightened due to chronic hyperglycemia or hyperinsulinemia. In advanced insulin resistance and T2D, the metabolic landscape becomes more complex, featuring differential tissue-specific alterations that affect OXPHOS. Recent findings suggest that addressing the metabolic imbalance in both cancer and diabetes could offer an effective treatment strategy. Numerous pharmaceutical and nutritional modalities exhibiting therapeutic effects in both conditions ultimately modulate the OXPHOS-glycolysis axis. Noteworthy nutritional adjuncts, such as alpha-lipoic acid, flavonoids, and glutamine, demonstrate the ability to reprogram metabolism, exerting anti-tumor and anti-diabetic effects. Similarly, pharmacological agents like metformin exhibit therapeutic efficacy in both T2D and cancer. This review discusses the molecular mechanisms underlying these metabolic shifts and explores promising therapeutic strategies aimed at reversing the metabolic imbalance in both disease scenarios.
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Accumulating evidence indicates that most primary Wharton's jelly mesenchymal stem cells (WJ-MSCs) therapeutic potential is due to their paracrine activity, i.e., their ability to modulate their microenvironment by releasing bioactive molecules and factors collectively known as secretome. These bioactive molecules and factors can either be released directly into the surrounding microenvironment or can be embedded within the membrane-bound extracellular bioactive nano-sized (usually 30-150 nm) messenger particles or vesicles of endosomal origin with specific route of biogenesis, known as exosomes or carried by relatively larger particles (100 nm-1 µm) formed by outward blebbing of plasma membrane called microvesicles (MVs); exosomes and MVs are collectively known as extracellular vesicles (EVs). The bioactive molecules and factors found in secretome are of various types, including cytokines, chemokines, cytoskeletal proteins, integrins, growth factors, angiogenic mediators, hormones, metabolites, and regulatory nucleic acid molecules. As expected, the secretome performs different biological functions, such as immunomodulation, tissue replenishment, cellular homeostasis, besides possessing anti-inflammatory and anti-fibrotic effects. This review highlights the current advances in research on the WJ-MSCs' secretome and its prospective clinical applications.
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Obesity is characterized by chronic low-grade inflammation. Obese people have higher levels of caveolin-1 (CAV1), a structural and functional protein present in adipose tissues (ATs). We aimed to define the inflammatory mediators that influence CAV1 gene regulation and the associated mechanisms in obesity. Using subcutaneous AT from 27 (7 lean and 20 obese) normoglycemic individuals, in vitro human adipocyte models, and in vivo mice models, we found elevated CAV1 expression in obese AT and a positive correlation between the gene expression of CAV1, tumor necrosis factor-alpha (TNF-α), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). CAV1 gene expression was associated with proinflammatory cytokines and chemokines and their cognate receptors (r ≥ 0.447, p ≤ 0.030), but not with anti-inflammatory markers. CAV1 expression was correlated with CD163, indicating a prospective role for CAV1 in the adipose inflammatory microenvironment. Unlike wild-type animals, mice lacking TNF-α exhibited reduced levels of CAV1 mRNA/proteins, which were elevated by administering exogenous TNF-α. Mechanistically, TNF-α induces CAV1 gene transcription by mediating NF-κB binding to its two regulatory elements located in the CAV1 proximal regulatory region. The interplay between CAV1 and the TNF-α signaling pathway is intriguing and has potential as a target for therapeutic interventions in obesity and metabolic syndromes.
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Caveolina 1 , NF-kappa B , Obesidade , Fator de Necrose Tumoral alfa , Animais , Humanos , Camundongos , Tecido Adiposo/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Inflamação/metabolismo , NF-kappa B/metabolismo , Obesidade/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Regulação para CimaRESUMO
Foamy and inflammatory macrophages play pathogenic roles in metabolic disorders. However, the mechanisms that promote foamy and inflammatory macrophage phenotypes under acute-high-fat feeding (AHFF) remain elusive. Herein, we investigated the role of acyl-CoA synthetase-1 (ACSL1) in favoring the foamy/inflammatory phenotype of monocytes/macrophages upon short-term exposure to palmitate or AHFF. Palmitate exposure induced a foamy/inflammatory phenotype in macrophages which was associated with increased ACSL1 expression. Inhibition/knockdown of ACSL1 in macrophages suppressed the foamy/inflammatory phenotype through the inhibition of the CD36-FABP4-p38-PPARδ signaling axis. ACSL1 inhibition/knockdown suppressed macrophage foaming/inflammation after palmitate stimulation by downregulating the FABP4 expression. Similar results were obtained using primary human monocytes. As expected, oral administration of ACSL1 inhibitor triacsin-C in mice before AHFF normalized the inflammatory/foamy phenotype of the circulatory monocytes by suppressing FABP4 expression. Our results reveal that targeting ACSL1 leads to the attenuation of the CD36-FABP4-p38-PPARδ signaling axis, providing a therapeutic strategy to prevent the AHFF-induced macrophage foaming and inflammation.
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Background: Animal and cell model studies have implicated CAV1 in the pathophysiology of metabolic disorders. Our previous studies demonstrated a potential association of CAV1 rs1997623 C/A variant with pediatric metabolic syndrome (MetS) in Arab children. In the present study, we evaluate whether the CAV1 variant associates with MetS Arab adults as well. The association signal is further examined for ancestry-specific variation by considering cohorts of other ethnicities. Method: The CAV1 rs1997623 was genotyped in three cohorts of Arab (n = 479), South Asian (n = 660), and South East Asian (n = 362) ethnic adults from Kuwait. MetS status of the individuals was diagnosed using the IDF criteria (presence of central obesity and at least two abnormalities out of: elevated TG, low HDL, hypertension, or T2D). The quantitative measure of MetS was calculated as siMS = 2 × WC/Height + FBG/5.6 + TG/1.7 + SBP/130-HDL/1.02 for males or HDL/1.28 for females. Allelic associations with quantitative and dichotomous MetS traits were assessed using linear and logistic regression models adjusted for age and sex. In addition, empirical p-values (P emp ) were generated using max(T) permutation procedure based on 10,000 permutations. Results: The CAV1 variant was significantly associated with MetS status (OR = 1.811 [1.25-2.61]; p-value = 0.0015; P emp = 0.0013) and with siMS (Effect size = 0.206; p-value = 0.0035; P emp = 0.0028) in the cohort of Arab individuals. The association was weak and insignificant in the South Asian and South East Asian cohorts (OR = 1.19 and 1.11; p-values = 0.25 and 0.67, respectively). Conclusion: The reported association of CAV1 rs1997623 C/A with MetS in Arab pediatric population is now demonstrated in an adult Arab cohort as well. The weak association signal seen in the Asian cohorts lead us to propose a certain extent of ethnic-specificity in CAV1 rs1997623 association with MetS.
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Caveolin-1 (CAV1) is implicated in the pathophysiology of diabetes and obesity. Previously, we demonstrated an association between the CAV1 rs1997623 C > A variant and metabolic syndrome (MetS). Here, we decipher the functional role of rs1997623 in CAV1 gene regulation. A cohort of 38 patients participated in this study. The quantitative MetS scores (siMS) of the participants were computed. CAV1 transcript and protein expression were tested in subcutaneous adipose tissue using RT-PCR and immunohistochemistry. Chromatin immunoprecipitation assays were performed using primary preadipocytes isolated from individuals with different CAV1 rs1997623 genotypes (AA, AC, and CC). The regulatory region flanking the variant was cloned into a luciferase reporter plasmid and expressed in human preadipocytes. Additional knockdown and overexpression assays were carried out. We show a significant correlation between siMS and CAV1 transcript levels and protein levels in human adipose tissue collected from an Arab cohort. We found that the CAV1 rs1997623 A allele generates a transcriptionally active locus and a new transcription factor binding site for early B-cell factor 1 (EBF1), which enhanced CAV1 expression. Our in vivo and in vitro combined study implicates, for the first time, EBF1 in regulating CAV1 expression in individuals harboring the rs1997623 C > A variant.
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Caveolina 1 , Síndrome Metabólica , Polimorfismo de Nucleotídeo Único , Transativadores , Humanos , Tecido Adiposo/metabolismo , Alelos , Sítios de Ligação , Caveolina 1/genética , Genótipo , Síndrome Metabólica/metabolismo , Transativadores/metabolismoRESUMO
Class switch recombination (CSR) is mediated by G-rich tandem repeated sequences termed switch regions. Transcription of switch regions generates single-stranded R loops that provide substrates for activation-induced cytidine deaminase. Mice deficient in MSH2 have a mild defect in CSR and analysis of their switch junctions has led to a model in which MSH2 is more critical for switch recombination events outside than within the tandem repeats. It is also known that deletion of the whole Sµ region severely impairs but does not abrogate CSR despite the lack of detectable R loops. Here, we demonstrate that deficiency of both MSH2 and the Sµ region completely abolishes CSR and that the abrogation occurs at the genomic level. This finding further supports the crucial role of MSH2 outside the tandem repeats. It also indicates that during CSR, MSH2 has access to activation-induced cytidine deaminase targets in R-loop-deficient Iµ-Cµ sequences rarely used in CSR, suggesting an MSH2-dependent DNA processing activity at the Iµ exon that may decrease with transcription elongation across the Sµ region.
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Linfócitos B/imunologia , Switching de Imunoglobulina/imunologia , Região de Troca de Imunoglobulinas/imunologia , Proteína 2 Homóloga a MutS/deficiência , Animais , Citometria de Fluxo , Ativação Linfocitária , Camundongos , Camundongos Knockout , Proteína 2 Homóloga a MutS/genética , Proteína 2 Homóloga a MutS/imunologia , Transcrição GênicaRESUMO
The fields of regenerative medicine and stem cell-based tissue engineering have the potential of treating numerous tissue and organ defects. The use of adult stem cells is of particular interest when it comes to dynamic applications in translational medicine. Recently, dental pulp stem cells (DPSCs) have been traced in third molars of adult humans. DPSCs have been isolated and characterized by several groups. DPSCs have promising characteristics including self-renewal capacity, rapid proliferation, colony formation, multi-lineage differentiation, and pluripotent gene expression profile. Nevertheless, genotypic, and phenotypic heterogeneities have been reported for DPSCs subpopulations which may influence their therapeutic potentials. The underlying causes of DPSCs' heterogeneity remain poorly understood; however, their heterogeneity emerges as a consequence of an interplay between intrinsic and extrinsic cellular factors. The main objective of the manuscript is to review the current literature related to the human DPSCs derived from the third molar, with a focus on their physiological properties, isolation procedures, culture conditions, self-renewal, proliferation, lineage differentiation capacities and their prospective advances use in pre-clinical and clinical applications.
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COVID-19 is challenging healthcare preparedness, world economies, and livelihoods. The infection and death rates associated with this pandemic are strikingly variable in different countries. To elucidate this discrepancy, we analyzed 2431 early spread SARS-CoV-2 sequences from GISAID. We estimated continental-wise admixture proportions, assessed haplotype block estimation, and tested for the presence or absence of strains' recombination. Herein, we identified 1010 unique missense mutations and seven different SARS-CoV-2 clusters. In samples from Asia, a small haplotype block was identified, whereas samples from Europe and North America harbored large and different haplotype blocks with nonsynonymous variants. Variant frequency and linkage disequilibrium varied among continents, especially in North America. Recombination between different strains was only observed in North American and European sequences. In addition, we structurally modelled the two most common mutations, Spike_D614G and Nsp12_P314L, which suggested that these linked mutations may enhance viral entry and replication, respectively. Overall, we propose that genomic recombination between different strains may contribute to SARS-CoV-2 virulence and COVID-19 severity and may present additional challenges for current treatment regimens and countermeasures. Furthermore, our study provides a possible explanation for the substantial second wave of COVID-19 presented with higher infection and death rates in many countries.
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Recombinação Genética , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Virulência/fisiologia , COVID-19/patologia , COVID-19/virologia , Bases de Dados Genéticas , Variação Genética , Haplótipos , Humanos , Desequilíbrio de Ligação , Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto , Análise de Componente Principal , Estrutura Terciária de Proteína , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
The imipramine ONC201 has antiproliferative effects in several cancer cell types and activates integrated stress response pathway associated with the induction of Damage Inducible Transcript 3 (DDIT3, also known as C/EBP homologous protein or CHOP). We investigated the signaling pathways through which ONC201/CHOP crosstalk is regulated in ONC201-treated nonmetastatic and metastatic cancer cell lines (Dukes' type B colorectal adenocarcinoma nonmetastatic SW480 and metastatic LS-174T cells, respectively). Cell proliferation and apoptosis were evaluated by MTT assays and flow cytometry, gene expression was assessed by Affymetrix microarray, signaling pathway perturbations were assessed in silico, and key regulatory proteins were validated by Western blotting. Unlike LS-174T cells, SW480 cells were resistant to ONC201 treatment; Gene Ontology analysis of differentially expressed genes showed that cellular responsiveness to ONC201 treatment also differed substantially. In both ONC201-treated cell lines, CHOP expression was upregulated; however, its upstream regulatory mechanisms were perturbed. Although, PERK, ATF6 and IRE1 ER-stress pathways upregulated CHOP in both cell types, the Bak/Bax pathway regulated CHOP only LS-174T cells. Additionally, CHOP RNA splicing profiles varied between cell lines; these were further modified by ONC201 treatment. In conclusion, we delineated the signaling mechanisms by which CHOP expression is regulated in ONC201-treated non-metastatic and metastatic colorectal cell lines. The observed differences could be related to cellular plasticity and metabolic reprogramming, nevertheless, detailed mechanistic studies are required for further validations.
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Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Imidazóis/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Piridinas/farmacologia , Pirimidinas/farmacologia , Fator de Transcrição CHOP/biossíntese , Processamento Alternativo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Biologia Computacional , Humanos , Metástase Neoplásica , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Transdução de Sinais , Sais de Tetrazólio , Tiazóis , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Microambiente Tumoral , Regulação para CimaRESUMO
The severity of the new COVID-19 pandemic caused by the SARS-CoV-2 virus is strikingly variable in different global populations. SARS-CoV-2 uses ACE2 as a cell receptor, TMPRSS2 protease, and FURIN peptidase to invade human cells. Here, we investigated 1,378 whole-exome sequences of individuals from the Middle Eastern populations (Kuwait, Qatar, and Iran) to explore natural variations in the ACE2, TMPRSS2, and FURIN genes. We identified two activating variants (K26R and N720D) in the ACE2 gene that are more common in Europeans than in the Middle Eastern, East Asian, and African populations. We postulate that K26R can activate ACE2 and facilitate binding to S-protein RBD while N720D enhances TMPRSS2 cutting and, ultimately, viral entry. We also detected deleterious variants in FURIN that are frequent in the Middle Eastern but not in the European populations. This study highlights specific genetic variations in the ACE2 and FURIN genes that may explain SARS-CoV-2 clinical disparity. We showed structural evidence of the functionality of these activating variants that increase the SARS-CoV-2 aggressiveness. Finally, our data illustrate a significant correlation between ACE2 variants identified in people from Middle Eastern origins that can be further explored to explain the variation in COVID-19 infection and mortality rates globally.
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It is estimated that in 2017 there were 451 million people with diabetes worldwide. These figures are expected to increase to 693 million by 2045; thus, innovative preventative programs and treatments are a necessity to fight this escalating pandemic disorder. Caveolin-1 (CAV1), an integral membrane protein, is the principal component of caveolae in membranes and is involved in multiple cellular functions such as endocytosis, cholesterol homeostasis, signal transduction, and mechanoprotection. Previous studies demonstrated that CAV1 is critical for insulin receptor-mediated signaling, insulin secretion, and potentially the development of insulin resistance. Here, we summarize the recent progress on the role of CAV1 in diabetes and diabetic complications.