Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Microcirculation ; 27(1): e12584, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390104

RESUMO

OBJECTIVES: The aim of this study was to investigate the response of a tumor and parent vessels to stimulating factors in the tumor microenvironment in different configurations. How a tumor grows and induces angiogenesis in different distances of a parent vessel is investigated. Moreover, interstitial fluid pressure and its effects on tumor cell phenotype are considered in the model. METHODS: A multiscale continuum-discrete model of a vascular tumor is utilized to simulate the growth of a cluster of tumor cells positioned in different distances of parent vessels. An agent-based probabilistic angiogenesis model is coupled to a discrete tumor model to simulate branching, anastomosis, blood flow, wall shear stress, and interstitial tumor pressure in which tumor cells are divided to necrotic, hypoxic, and proliferative. RESULTS: Starting the simulations from 9 initial tumor cells, the model proved that tumors grow to a certain size and also reach to a certain distance before being able to induce sprouting. For tumors placed 2 and 2.5 mm away from a parent vessel, initiation of angiogenesis is delayed significantly in comparison with closer distances. For the initial cluster positioned in a distance of 2.5 mm away, first sprout is seen after 47 days. Moreover, dendritic shape of the tumor is seen prior to angiogenesis which is a sign of cells being starved and wandered in the domain to reach the oxygen source. The trend of tumor growth obeys power law function which aligns with the experimental results. DISCUSSION: The mathematical model revealed the importance of geometry and position of an initial tumor cluster in determining the behavior and final architecture of a vascular tumor. As a tumor cell appears in farther distances from a parent vessel, duration of its growth and inducing angiogenesis becomes longer and the chance of suppressing the tumor in the initial days of growth is higher. Also, the importance of angiogenesis in making tumors devastating is again corroborated by mathematical models.


Assuntos
Modelos Cardiovasculares , Neovascularização Patológica/fisiopatologia , Neoplasias Vasculares , Animais , Humanos , Neoplasias Vasculares/irrigação sanguínea , Neoplasias Vasculares/fisiopatologia
2.
BMC Med Genet ; 21(1): 127, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517708

RESUMO

BACKGROUND: Hearing loss (HL) is the most common sensorineural disorder with high phenotypic and genotypic heterogeneity, which negatively affects life quality. Autosomal recessive non-syndromic hearing loss (ARNSHL) constitutes a major share of HL cases. In the present study, Whole exome sequencing (WES) was applied to investigate the underlying etiology of HL in an Iranian patient with ARNSHL. METHODS: A proband from an Iranian consanguineous family was examined via WES, following GJB2 sequencing. WES was utilized to find possible genetic etiology of the disease. Various Bioinformatics tools were used to assess the pathogenicity of the variants. Co-segregation analysis of the candidate variant was carried out. Interpretation of variants was performed according to the American College of Medical Genetics and Genomics (ACMG) guidelines. RESULTS: WES results showed a novel frameshift (16 bp deletion) variant (p.Ala170Alafs*20) in the LRTOMT gene. This variant, which resides in exon 6, was found to be co-segregating in the family. It fulfils the criteria set by the ACMG guidelines of being pathogenic. CONCLUSION: Here, we report successful application of WES to identify the molecular pathogenesis of ARNSHL, which is a genetically heterogeneous disorder, in a patient with ARNSHL.


Assuntos
Genes Recessivos , Perda Auditiva Neurossensorial/genética , Mutação/genética , Proteínas/genética , Sequência de Aminoácidos , Sequência de Bases , Pré-Escolar , Família , Humanos , Irã (Geográfico) , Masculino , Modelos Moleculares , Proteínas/química
3.
Mol Biol Rep ; 47(7): 5355-5364, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32623615

RESUMO

Autosomal recessive non-syndromic hearing loss (ARNSHL) is a highly heterogeneous disease, for which more than 70 genes have been identified. MYO15A mutations have been reported to cause congenital severe-to-profound HL. In this study, we applied the whole exome sequencing (WES) to find the cause of HL in an Iranian family. A proband from an Iranian non-consanguineous family with hearing impaired parents, was examined via WES, after excluding GJB2 mutations as the most common ARNSHL gene via Sanger sequencing. Co-segregation analysis of the candidate variant was done in the family members. Interpretation of variants was according to the American College of Medical Genetics and Genomics (ACMG) guidelines. WES results showed novel compound heterozygous variants (p.Arg1507Ter and p.Val2815Valfs*10) in the MYO15A gene. These two variants, residing in highly conserved regions, were found to be co-segregating in the family and fulfill the criteria of being categorized as pathogenic, according to the ACMG guidelines. Here, we report successful application of WES to identify the molecular pathogenesis of ARNSHL in a patient with ARNSHL, as an example of an extremely heterogeneous disease. In agreement with previous studies, MYO15A is regarded to be important in causing HL in Iran.


Assuntos
Surdez/genética , Miosinas/genética , Adulto , Criança , Exoma/genética , Feminino , Genes Recessivos/genética , Genômica/métodos , Perda Auditiva/genética , Humanos , Irã (Geográfico) , Masculino , Mutação/genética , Miosinas/metabolismo , Linhagem , Sequenciamento do Exoma/métodos
4.
Biol Trace Elem Res ; 202(3): 1288-1304, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37392361

RESUMO

As a leading global cause of mortality, cancer continues to pose a significant challenge. The shortcomings of prevalent cancer treatments, such as surgery, radiation therapy, and chemotherapy, necessitate the exploration of alternative therapeutic strategies. Selenium nanoparticles (SeNPs) have emerged as a promising solution, with their synthesis being widely researched due to their potential applications. Among the diverse synthesis methods for SeNPs, the green chemistry approach holds a distinctive position within nanotechnology. This research delves into the anti-proliferative and anticancer properties of green-synthesized SeNPs via the cell-free supernatant (CFS) of Lactobacillus casei (LC-SeNPs), with a specific focus on MCF-7 and HT-29 cancer cell lines. SeNPs were synthesized employing the supernatant of L. casei. The characterization of these green-synthesized SeNPs was performed using TEM, FE-SEM, XRD, FT-IR, UV-vis, energy-dispersive X-ray spectroscopy, and DLS. The biological impact of LC-SNPs on MCF-7 and HT-29 cancer cells was examined via MTT, flow cytometry, scratch tests, and qRT-PCR. Both FE-SEM and TEM images substantiated the spherical shape of the synthesized nanoparticles. The biosynthesized LC-SNPs reduced the survival of MCF-7 (by 20%) and HT-29 (by 30%) cells at a concentration of 100 µg/mL. Flow cytometry revealed that LC-SNPs were capable of inducing 28% and 23% apoptosis in MCF-7 and HT-29 cells, respectively. In addition, it was found that LC-SNPs treated MCF-7 and HT-29 cells were arrested in the sub-G1 phase. Gene expression analysis indicated that the expression levels of the CASP3, CASP9, and BAX genes were elevated after treating MCF-7 and HT-29 cells with LC-SNPs. Further, SeNPs were observed to inhibit migration and invasion of MCF-7 and HT-29 cancer cells. The SeNPs, produced via L. casei, demonstrated strong anticancer effects on MCF-7 and HT-29 cells, suggesting their potential as biological agents in cancer treatment following additional in vivo experiments.


Assuntos
Neoplasias da Mama , Neoplasias do Colo , Lacticaseibacillus casei , Nanopartículas , Selênio , Humanos , Feminino , Selênio/metabolismo , Neoplasias da Mama/tratamento farmacológico , Células HT29 , Células MCF-7 , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química , Neoplasias do Colo/tratamento farmacológico , Apoptose , Pontos de Checagem do Ciclo Celular
5.
BMC Med Genomics ; 17(1): 173, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38956522

RESUMO

BACKGROUND: Autosomal recessive non-syndromic hearing loss (NSHL) and cone dystrophies (CODs) are highly genetically and phenotypically heterogeneous disorders. In this study, we applied the whole exome sequencing (WES) to find the cause of HL and COD in an Iranian consanguineous family with three affected individuals. METHODS: Three members from an Iranian consanguineous family who were suffering from NSHL and visual impairment were ascertained in this study. Comprehensive clinical evaluations and genetic analysis followed by bioinformatic and co-segregation studies were performed to diagnose the cause of these phenotypes. Data were collected from 2020 to 2022. RESULTS: All cases showed congenital bilateral NSHL, decreased visual acuity, poor color discrimination, photophobia and macular atrophy. Moreover, cornea, iris and anterior vitreous were within normal limit in both eyes, decreased foveal sensitivity, central scotoma and generalized depression of visual field were seen in three cases. WES results showed two variants, a novel null variant (p.Trp548Ter) in the PDE6C gene causing COD type 4 (Achromatopsia) and a previously reported variant (p.Ile84Thr) in the PDZD7 gene causing NSHL. Both variants were found in the cis configuration on chromosome 10 with a genetic distance of about 8.3 cM, leading to their co-inheritance. However, two diseases could appear independently in subsequent generations due to crossover during meiosis. CONCLUSIONS: Here, we could successfully determine the etiology of a seemingly complex phenotype in two adjacent genes. We identified a novel variant in the PDE6C gene, related to achromatopsia. Interestingly, this variant could cooperatively cause visual disorders: cone dystrophy and cone-rod dystrophy.


Assuntos
Defeitos da Visão Cromática , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6 , Linhagem , Adulto , Criança , Feminino , Humanos , Masculino , Defeitos da Visão Cromática/genética , Consanguinidade , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/genética , Sequenciamento do Exoma , Proteínas do Olho , Perda Auditiva/genética , Irã (Geográfico) , Mutação , Fenótipo
6.
J Genet ; 1022023.
Artigo em Inglês | MEDLINE | ID: mdl-37731250

RESUMO

Intellectual disability (ID) is a highly heterogeneous disorder, affecting 1-3% of the world's population, which is associated with a significant disorder in cognitive development, adaptive functioning and behavioural problems in human life. In this study, due to the genetic heterogeneity of the disease, the whole-exome sequencing (WES) was performed on a 13-year-old boy suffering from microcephaly. In addition, Sanger sequencing, cosegregation analysis, and structural modelling were performed to identify and verify the causative variant in the proband and obligate carriers in the family. WES revealed a novel, homozygote 10-bp deletion in the donor splice site of 2nd exon of METTL5 gene (NM_014168:c.223_224?8del), which was found segregating with the phenotype in the pedigree. This variant meets the criteria of being pathogenic according to the American College of Medical Genetics (ACMG) variant interpretation guideline. Up to now, four pathogenic homozygous variants of the METTL5 gene have been reported that are associated with ID. A comparison of the clinical characteristics of our patient with previously reported cases revealed variability in the disease severity and some clinical presentations, including overall growth, dysmorphic facial features and behavioural psychiatric manifestations. The clinical findings of the case reported in this study extend the spectrum of genetic variations and phenotypes associated with ID and provide a better insight of the disease pathogenesis.


Assuntos
Deficiência Intelectual , Microcefalia , Masculino , Humanos , Adolescente , Deficiência Intelectual/genética , Irã (Geográfico) , Microcefalia/genética , Cognição , Éxons
7.
PLoS One ; 18(2): e0282304, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36848337

RESUMO

Metachromatic leukodystrophy (MLD) is a neurodegenerative lysosomal storage disease caused by a deficiency in the arylsulfatase A (ARSA). ARSA deficiency leads to sulfatide accumulation, which involves progressive demyelination. The profound impact of early diagnosis on MLD treatment options necessitates the development of new or updated analysis tools and approaches. In this study, to identify the genetic etiology in a proband from a consanguineous family with MLD presentation and low ARSA activity, we employed Whole-Exome Sequencing (WES) followed by co-segregation analysis using Sanger sequencing. Also, MD simulation was utilized to study how the variant alters the structural behavior and function of the ARSA protein. GROMACS was applied and the data was analyzed by RMSD, RMSF, Rg, SASA, HB, atomic distance, PCA, and FEL. Variant interpretation was done based on the American College of Medical Genetics and Genomics (ACMG) guidelines. WES results showed a novel homozygous insertion mutation, c.109_126dup (p.Asp37_Gly42dup), in the ARSA gene. This variant is located in the first exon of ARSA, fulfilling the criteria of being categorized as likely pathogenic, according to the ACMG guidelines and it was also found to be co-segregating in the family. The MD simulation analysis revealed this mutation influenced the structure and the stabilization of ARSA and led to the protein function impairment. Here, we report a useful application of WES and MD to identify the causes of a neurometabolic disorder.


Assuntos
Leucodistrofia Metacromática , Doenças por Armazenamento dos Lisossomos , Humanos , Leucodistrofia Metacromática/genética , Simulação de Dinâmica Molecular , Sequenciamento do Exoma , Cerebrosídeo Sulfatase/genética , Esterases
8.
Cancers (Basel) ; 15(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37296861

RESUMO

The association between oral microbiota and cancer development has been a topic of intense research in recent years, with compelling evidence suggesting that the oral microbiome may play a significant role in cancer initiation and progression. However, the causal connections between the two remain a subject of debate, and the underlying mechanisms are not fully understood. In this case-control study, we aimed to identify common oral microbiota associated with several cancer types and investigate the potential mechanisms that may trigger immune responses and initiate cancer upon cytokine secretion. Saliva and blood samples were collected from 309 adult cancer patients and 745 healthy controls to analyze the oral microbiome and the mechanisms involved in cancer initiation. Machine learning techniques revealed that six bacterial genera were associated with cancer. The abundance of Leuconostoc, Streptococcus, Abiotrophia, and Prevotella was reduced in the cancer group, while abundance of Haemophilus and Neisseria enhanced. G protein-coupled receptor kinase, H+-transporting ATPase, and futalosine hydrolase were found significantly enriched in the cancer group. Total short-chain fatty acid (SCFAs) concentrations and free fatty acid receptor 2 (FFAR2) expression levels were greater in the control group when compared with the cancer group, while serum tumor necrosis factor alpha induced protein 8 (TNFAIP8), interleukin-6 (IL6), and signal transducer and activator of transcription 3 (STAT3) levels were higher in the cancer group when compared with the control group. These results suggested that the alterations in the composition of oral microbiota can contribute to a reduction in SCFAs and FFAR2 expression that may initiate an inflammatory response through the upregulation of TNFAIP8 and the IL-6/STAT3 pathway, which could ultimately increase the risk of cancer onset.

9.
Mol Genet Genomic Med ; 10(10): e2034, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35962714

RESUMO

BACKGROUND: X-linked mental retardation-hypotonic facies syndrome-1 (MRXFH1), caused by a mutation in the ATRX gene, is a rare syndromic form of X-linked mental retardation (XLMR) that is mainly characterized by severe intellectual disability, dysmorphic facies, and skewed X-inactivation pattern in carrier women. METHOD: In this study, due to the genetic heterogeneity of the disease, we performed exome sequencing (ES) on a 15-year-old boy with primary microcephaly and intellectual disability. Also, Sanger sequencing, cosegregation analysis, and structural modeling were done to identify and verify the causative variant in the proband and other affected individuals in the family. In addition, we collected data from previously reported cases to compare with our patients' phenotypes. RESULTS: ES revealed a previously reported missense variant in the ATRX gene (c.5182G > C, p.Ala1728Pro), segregating with the new clinical characteristic including primary microcephaly in the pedigree. This variant meets the criteria of being likely pathogenic based on the ACMG variant interpretation guideline. CONCLUSIONS: The findings of this study extend the spectrum of phenotypes associated with the identified variant and provide further details on its clinical features.


Assuntos
Deficiência Intelectual , Deficiência Intelectual Ligada ao Cromossomo X , Microcefalia , Surdez , Exoma , Feminino , Transtornos do Crescimento , Humanos , Hipogonadismo , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Microcefalia/genética , Mutação , Proteína Nuclear Ligada ao X/genética
10.
Microb Biotechnol ; 15(3): 817-831, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33729663

RESUMO

Endothermic mammals have a high energy cost to maintain a stable and high body temperature (Tb , around 37°C). Thyroid hormones are a major regulator for energy metabolism and Tb . The gut microbiota is involved in modulating host energy metabolism. However, whether the interaction between the gut microbiota and thyroid hormones is involved in metabolic and thermal regulations is unclear. We hypothesized that thyroid hormones via an interaction with gut microbiota orchestrate host thermogenesis and Tb . l-thyroxine-induced hyperthyroid Mongolian gerbils (Meriones unguiculatus) increased resting metabolic rate (RMR) and Tb , whereas Methimazole-induced hypothyroid animals decreased RMR. Both hypothyroid and hyperthyroid animals differed significantly in faecal bacterial community. Hyperthyroidism increased the relative abundance of pathogenic bacteria, such as Helicobacter and Rikenella, and decreased abundance of beneficial bacteria Butyricimonas and Parabacteroides, accompanied by reduced total bile acids and short-chain fatty acids. Furthermore, the hyperthyroid gerbils transplanted with the microbiota from control donors increased type 2 deiodinase (DIO2) expression in the liver and showed a greater rate of decline of both serum T3 and T4 levels and, consequently, a more rapid recovery of normal RMR and Tb . These findings indicate that thyroid hormones regulate thermogenesis depending on gut microbiota and colonization with normal microbiota by caecal microbial transplantation attenuates hyperthyroid-induced thermogenesis. This work reveals the functional consequences of the gut microbiota-thyroid axis in controlling host metabolic physiology and Tb in endotherms.


Assuntos
Hipertireoidismo , Termogênese , Animais , Ceco/microbiologia , Gerbillinae/metabolismo , Hipertireoidismo/terapia , Termogênese/fisiologia , Hormônios Tireóideos/metabolismo
11.
Neuromuscul Disord ; 32(9): 776-784, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35989179

RESUMO

Muscular dystrophy (MD) is a group of multiple muscle diseases, which causes severely impaired motor ability, degeneration and dysfunctions in the musculoskeletal system, respiratory failure and feeding difficulties. LAMA2-related MD is caused by pathogenic variants in the LAMA2 gene, encoding laminin a2 chain, a component of the skeletal muscle extracellular matrix protein laminin-α2ß1γ1. We performed clinical examination and molecular genetic analysis in a patient with congenital MD (CMD), and autism-like phenotype. We performed whole exome sequencing (WES) to find possible genetic etiology of CMD in an Iranian non-consanguineous patient. The pathogenicity of the variants was assessed using various Bioinformatics tools. American College of Medical Genetics and Genomics (ACMG) guidelines were used to interpret the variant and Sanger sequencing in the patient and her family was applied for the confirmation of the variant. WES results showed a novel frameshift homozygous variant (p.Tyr1313LeufsTer4) in the LAMA2 gene leading to the CMD phenotype. This variant resides in a highly conserved region and was found to be co-segregating in the family. It fulfils the criteria of being pathogenic. We successfully identified a novel LAMA2 pathogenic variant in an Iranian patient suffering from CMD and autism using WES. Identification of disease-causing variant in autosomal recessive disorders such as CMD can be useful in genetic counseling, prenatal diagnosis, and predicting prognosis of the disease.


Assuntos
Transtorno Autístico , Cardiomiopatias , Laminina/genética , Distrofias Musculares , Feminino , Mutação da Fase de Leitura , Humanos , Irã (Geográfico) , Distrofias Musculares/complicações , Distrofias Musculares/congênito , Distrofias Musculares/genética , Sequenciamento do Exoma
12.
NPJ Biofilms Microbiomes ; 8(1): 16, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379849

RESUMO

Regulating sodium and water balances is crucial for survival of small, desert mammals. Studies demonstrate that the gut microbiota and their metabolites are involved in host energy homeostasis, but little is known on the interactions among salt loading, gut microbiota, and osmoregulation. The aim of this study was to fill this gap. Mongolian gerbils (Meriones unguiculatus) were offered drinking water (Con) and either water containing moderate (4%, MS) or high NaCl (8%, HS) ad libitum. Intake of HS reduced α diversity of the microbial community and, at the genus level, reduced the relative abundances of Rikenella and Christensenella but increased Atopobium. To confirm the function of gut microbiota in host osmoregulation, we transplanted caecal microbiota in HS gerbils. To cope with salt loading, the gerbils concentrated urine, resulting in negative energy balance and systemic inflammation. The HS gerbils increased hypothalamic arginine vasopressin and intestinal and renal aquaporin 2 to support water retention, and reduced intestinal and renal epithelial sodium channel α to promote sodium excretion. However, HS gerbils with caecal microbiota transplant (CMT) from Con donors maintained energy balance and osmoregulation, and had a much reduced systemic inflammation. Further, CMT from Con donors to HS recipients reshaped the gut microbiota, particularly by reducing Parabacteroides distasonis and Prevotella copri, and increasing Lactobacillus reuteri abundances, with a resulting increase in bacterial metabolites such as butyrate. These findings highlight a vital role of the microbiota-gut-kidney axis in mediating salt-related osmoregulation, allowing small mammals to adapt to high salt loads in a desert habitat.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Rim , Mamíferos , Osmorregulação
13.
Dig Dis Sci ; 56(12): 3577-82, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21847566

RESUMO

BACKGROUND: Esophageal cancer accounts for a considerable proportion of carcinomas of the upper gastrointestinal tract in African Americans. Our aim was to describe the epidemiology of esophageal squamous cell cancer (ESCC) and esophageal adenocarcinoma (EA) among African Americans in the last five decades. METHODS: A total of 601 records of patients with documented esophageal cancer between 1959 and 2007 at Howard University Hospital were reviewed. Demographic characteristics, risk factors, clinical stage and histological findings were reviewed. The change in prevalence of the disease and the interaction between main risk factors with tumor stage of the patients were assessed over the years of this study. RESULT: A total of 552 patients (91.8%) had ESCC while 49 patients (8.2%) had EA. The mean age at diagnosis was 60.1 and 60.6 years for ESCC and EA, respectively (P = 0.8). The peak incidence was in the 1980-1989 decade. Out of 136 ESCC patients with TNM staging information, 130 (95.6%) were diagnosed in stage 2 and above. The majority (73%) of the ESCC were in the mid- and upper third of the esophagus and associated with smoking and alcohol exposure. The majority (81%) of the EA were in the mid- and lower third. The most common presenting symptoms were dysphagia (77.7%), and weight loss (31.9%). CONCLUSION: ESCC is the predominant esophageal cancer in African Americans and diagnosed in late stages, and its diagnosis in our institution has decreased since 1990. A combination of genetic factors, environmental influences (e.g., those related to diet), and the deleterious changes associated with smoking and alcohol consumption, and differences in tumor histology, are the obvious parameters that should be the focus of future studies, and early diagnosis at an earlier stage should be considered among blacks.


Assuntos
Negro ou Afro-Americano , Carcinoma de Células Escamosas/etnologia , Neoplasias Esofágicas/etnologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , District of Columbia/epidemiologia , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
14.
J Comp Physiol B ; 190(5): 641-654, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32556536

RESUMO

Desert rodents are faced with many challenges such as high dietary salt in their natural habitats and they have evolved abilities to conserve water and tolerate salt. However, the physiological and molecular mechanisms involved in water and salt balances in desert rodents are unknown. We hypothesized that desert rodents regulated water and salt balances by altering the expression of AQP2 and α-ENaC in the kidney. Mongolian gerbils (Meriones unguiculatus), a desert species, were acclimated to drinking water with different salt contents: (0, control; 4% NaCl, moderate salt, MS; 8% NaCl, high salt, HS) for 4 weeks. The gerbils drinking salty water had lower body mass, food intake, water intake, metabolic water production and urine volume. The HS gerbils increased the expression of arginine vasopressin (AVP) in the hypothalamus, and also enhanced the expression of AQP2 and cAMP/PKA/CREB signaling pathway in the kidney. In addition, these gerbils reduced serum aldosterone levels and α-ENaC expression in the kidney. Creatinine clearance was lower in the HS group than that in the control group, but serum and urine creatinine levels did not change. These data indicate that desert rodents rely on AVP-dependent upregulation of AQP2 and aldosterone-dependent downregulation of α-ENaC in the kidney to promote water reabsorption and sodium excretion under high salt intake.


Assuntos
Gerbillinae/metabolismo , Cloreto de Sódio na Dieta/administração & dosagem , Equilíbrio Hidroeletrolítico , Aldosterona/sangue , Animais , Aquaporina 2/metabolismo , Arginina Vasopressina/metabolismo , Metabolismo Basal , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ingestão de Líquidos , Ingestão de Alimentos , Canais Epiteliais de Sódio/metabolismo , Fezes/química , Gerbillinae/sangue , Gerbillinae/urina , Hipotálamo/metabolismo , Rim/anatomia & histologia , Rim/metabolismo , Masculino , Concentração Osmolar , Água/metabolismo
15.
mSystems ; 5(5)2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082280

RESUMO

Ambient temperature (Ta ) is an important factor in shaping phenotypic plasticity. Plasticity is generally beneficial for animals in adapting to their environments. Gut microbiota are crucial in regulating host physiological and behavioral processes. However, whether the gut microbiota play a role in regulating host phenotypic plasticity under the conditions of repeated fluctuations in environmental factors has rarely been examined. We used intermittent Ta acclimations to test the hypothesis that the plasticity of gut microbiota confers on the host a metabolic adaptation to Ta fluctuations. Mongolian gerbils (Meriones unguiculatus) were acclimated to intermittent 5°C to 23°C, 37°C to 23°C or 23°C to 23°C conditions for 3 cycles (totally 3 months). Intermittent Ta acclimations induced variations in resting metabolic rate (RMR), serum thyroid hormones, and core body temperature (Tb ). We further identified that the ß-diversity of the microbial community varied with Ta and showed diverse responses during the 3 cycles. Some specific bacteria were more sensitive to Ta and were associated with host dynamic metabolic plasticity during Ta acclimations. In addition, depletion of gut microbiota in antibiotic-treated gerbils impaired metabolic plasticity, particularly at low Ta , whereas supplementation with propionate as an energy resource improved the inhibited thermogenic capacity and increased the survival rate in the cold. These findings demonstrate that both gut microbiota and their host were more adaptive after repeated acclimations, and dynamic gut microbiota and their metabolites may confer host plasticity in thermoregulation in response to Ta fluctuations. It also implies that low Ta is a crucial cue in driving symbiosis between mammals and their gut microbiota during evolution.IMPORTANCE Whether gut microbiota play a role in regulating host phenotypic plasticity in small mammals living in seasonal environments has rarely been examined. The present study, through an intermittent temperature acclimation model, indicates that both gut microbiota and their host were more adaptive after repeated acclimations. It also demonstrates that dynamic gut microbiota confer host plasticity in thermoregulation in response to intermittent temperature fluctuations. Furthermore, low temperature seems to be a crucial cue in driving the symbiosis between mammals and their gut microbiota during evolution.

16.
Adv Biomed Res ; 9: 25, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072637

RESUMO

BACKGROUND: Diabetes mellitus (DM) is a group of metabolic disorders in the body, accompanied with increasing blood sugar levels. Diabetes is classified into three groups: Type 1 DM (T1DM), Type 2 DM (T2DM), and monogenic diabetes. Maturity-onset diabetes of the young (MODY) is a monogenic diabetes that is frequently mistaken for T1D or T2D. The aim of this study was to diagnose MODY and its subtype frequency in a diabetic population in Iran. MATERIALS AND METHODS: In this study among ten diabetic families that were highly suspected to MODY by nongenetic biomarkers and without any pathogenic mutation in GCK and HNF1A genes, two patients from two unrelated families were examined via whole-exome sequencing (WES) in order to detect the causative gene of diabetes. Co-segregation analysis of the identified variant was performed using Sanger sequencing. RESULTS: In this study, no pathogenic variant was found in GCK and HNF1A genes (MODY2 and MODY3), while these two types of MODY were introduced as the most frequent in other studies. By using WES, a pathogenic variant (p.I488T) was found in one of the patients in CEL gene causing MODY8 that its frequency is very rare in other studied populations. A high-risk variant associated with diabetes was found in another patient. CONCLUSION: WES was applied in this study to reveal the cause of MODY in 1 family. This pathogenic mutation was previously reported as a disease causing mutation.

17.
Iran J Public Health ; 49(10): 1947-1953, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33346226

RESUMO

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most important types of oral malignancies. DKK gene family members as well as DKK2/4 have critical roles in regulation of Wnt signaling as one of the main determining pathway in oral carcinogenesis. This study aimed to identify promoter methylation status of DKK2/4 genes to provide possible biomarkers for early detection and treatment of OSCC patients. METHODS: A case control study was performed on 31 fresh tissues obtained from oral cavity of patients affected by OSCC and 31 fresh corresponding tissues from normal healthy controls in Tehran and, between the years of 2016-2018. Purified DNA from tissue samples was subjected to bisulfite treatment and then methylation specific polymerase chain reaction (MSP-PCR) was carried out on treated DNA samples. RESULTS: DKK4 promoter was methylated in none of OSCC samples while it was methylated in 16.1% of healthy controls. 16.1% of OSCC samples were detected to be semimethylated and 22.6% of healthy normal samples were methylated for DKK2 promoter gene. Meaningful difference was found in DKK4 promoter methylation among OSCC patients and healthy controls. Significant correlation was found between DKK4 promoter methylation and tumor grade. The age of all enrolled samples was demonstrated to have strong effect on promoter methylation of studied genes. CONCLUSION: Hypomethylation of DKK2 and DKK4 genes in higher grades of OSCC samples may indicate the pivotal role of their expression in tumor cells invasion and progression through modulation of Wnt signaling pathway. Further study required to determine simultaneous expression of those genes and Wnt signaling elements at mRNA and protein levels.

18.
Artigo em Inglês | MEDLINE | ID: mdl-30476595

RESUMO

Oxidative damage is a potential physiological cost of thermoregulation during seasonal adjustments to air temperature (Ta) in small mammals. Here, we hypothesized that Ta affects serum thyroid hormone levels and these hormones can mediate the changes in metabolic rate and oxidative damage. Mongolian gerbils (Meriones unguiculatus) were acclimated at different Tas (5 °C, 23 °C and 37 °C) for 3 weeks. Serum tri-iodothyronine (T3) levels increased at 5 °C but decreased at 37 °C compared to the control (23 °C). Protein carbonyls increased in liver at 37 °C compared with control, however, lipid damage (malonaldehyde, MDA) in both serum and liver was unrelated to Ta. After the effects of different Tas on thyroid hormone levels and oxidative damage markers were determined, we further investigate whether thyroid hormones mediated metabolic rate and oxidative damage. Another set of gerbils received 0.0036% L-thyroxin (hyperthyroid), 0.04% Methylimazol (hypothyroid) or water (control). Hypothyroid group showed a 34% reduction in resting metabolic rate (RMR) also 42% and 26% increases in MDA and liver protein carbonyl respectively, whereas hyperthyroid group had higher RMR, liver mass and superoxide dismutase (SOD) compared to control. Serum T3 or T3/T4 levels were correlated positively with RMR, liver mass, and SOD, but negatively with MDA and uncoupling protein 2 (UCP2). We concluded that high Ta induced hypothyroidism, decreased RMR and increased oxidative damage, whereas low Ta induced hyperthyroidism, increased RMR and unchanged oxidative damage. These data supported our hypothesis that thyroid hormones can be a cue to mediate metabolic rate and different aspects of oxidative and antioxidant activities at different Tas.


Assuntos
Metabolismo Basal/fisiologia , Gerbillinae/fisiologia , Oxirredução , Hormônios Tireóideos/fisiologia , Animais , Antioxidantes/metabolismo , Gerbillinae/metabolismo , Fígado/metabolismo , Malondialdeído/metabolismo , Carbonilação Proteica/fisiologia , Superóxido Dismutase/metabolismo , Temperatura , Proteína Desacopladora 2/metabolismo
19.
Int Immunopharmacol ; 74: 105730, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31299610

RESUMO

BACKGROUND: RIF is clinically defined as the failure of good quality embryos to implant into the uterus following at least three cycles of In Vitro Fertilization/Embryo Transfer (IVF/ET). During human pregnancy, a genetically different fetus is allowed to survive within the uterus despite the maternal recognition of fetal alloantigens. Compared with normal pregnant women, early loss of embryo is associated with systemic lower levels of Treg cells in IVF. Moreover, several lines of evidence have indicated that differentiation of naive T cells into Th17 is deleterious for normal pregnancy and may cause implantation failure. Sirolimus as the most common mTOR (mammalian target of Rapamycin) inhibitor is able to effectively prevent allograft rejection. Here we aimed to evaluate Sirolimus effects on Th17/Treg axis and subsequently on pregnancy outcome. METHODS AND MATERIALS: 121 patients with a history of at least 3 implatation failures were selected and enrolled in this clinical trial. Blood was drawn between days 5 and 10 of the cycle prior to the index IVF/ET cycle to assess baseline value of Th17 cells and regulatory T cells ratios using flowcytometry. A Th17/Treg cell ratio equal or >0.74 was considered to be the elevated Th17/Treg cell ratio. In 76 patients with elevated Th17/Treg ratios, 43 individuals were treated with Sirolimus and 33 remained untreated. RESULTS: Our results demonstrated that Sirolimus treatment led to an increase in Treg cells number and function in treated group and reduced the frequency and function of Th17 cells. Moreover Th17/Treg cell ratio, significantly reduced from 1.18 ±â€¯0.46% to 0.9 ±â€¯0.45% following Sirolimus intervention (P = 0.024). In contrast, no significant difference in Th17 and Treg cell frequencies and Th17/Treg cell ratio was observed in untreated control subjects before and after ET. Finally our data showed a significantly higher clinical pregnancy rate (55.81%) in Sirolimus-treated patients compared with control group (24.24%) (P < 0.0005). We also found a significantly increased live birth rate (48.83%) in RIF women who received Sirolimus compared with control group (21.21%) (P < 0.0001). CONCLUSION: The findings of the current study revealed the fact that Sirolimus exhibit potent immunosuppressive effects by blocking intracellular immune responses downstream of co-stimulatory signals, also is able to improve reproductive outcome in RIF women with imbalanced Th17/Treg ratio by modulate of Th17 /Treg axis, thus representing a new approach for the potential treatment of patients with embryo implantation failure.


Assuntos
Aborto Habitual/tratamento farmacológico , Imunossupressores/uso terapêutico , Sirolimo/uso terapêutico , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Adulto , Método Duplo-Cego , Implantação do Embrião , Feminino , Fertilização in vitro , Humanos , Tolerância Imunológica , Gravidez , Taxa de Gravidez
20.
Med Sci (Basel) ; 6(2)2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29751685

RESUMO

Probiotics have beneficial effects on management of type 2 diabetes (T2D). The major hallmarks of T2D are insulin deficiency and insulin resistance which emphasize insulin therapy in onset of disease. Lactobacilli such as Lactobacillus acidophilus (L. acidophilus) have well known properties on prevention of T2D and insulin resistance but not on insulin degradation. Insulin-degrading enzyme (IDE) degrades insulin in the human body. We studied the effects of cell-free supernatant (CFS) and ultraviolet (UV)-killed L. acidophilus (ATCC 314) on IDE activity and insulin degradation in vitro. Cell growth inhibition by CFS and UV-killed L. acidophilus (ATCC 314) was studied and Western blotting and a fluoregenic assay was performed to determine IDE expression and its activity, respectively. Insulin degradation was evaluated by sandwich enzyme-linked immunosorbent assay(ELISA). IDE expression and activity was reduced by CFS and UV-killed L. acidophilus (ATCC 314). Although, decreased enzyme expression and activity was not significant for CFS in contrast to MRL (MRS with same pH as CFS). Also, reduction in IDE activity was not statistically considerable when compared to IDE expression. Insulin degradation was increased by CFS but decreased by UV-killed L. acidophilus (ATCC 314).

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa