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1.
Environ Toxicol Chem ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837804

RESUMO

The on-going anthropogenic degradation of freshwater habitats has drastically altered the environmental supply of both nutrients and common pollutants. Most organisms living in these altered habitats experience interactive effects of various stressors that can initiate adjustments at multiple levels impacting their fitness. Hence, studies measuring response to a single environmental parameter fail to capture the complexities of the status quo. We tested both the individual and the interactive effect of arsenic (As) exposure, food quantity, and dietary phosphorus (P)-supply on six life-history traits (Juvenile Growth Rate; Adult Growth Rate; Age and Size at Maturity, Lifespan, and Fecundity) as surrogates for organismal fitness in the keystone aquatic grazer Daphnia pulex. We also tested the effect of food quantity and P-supply on somatic As accumulation in Daphnia. Our results indicated an influence of P-supply on neonatal growth and an influence of As and food quantity on growth and maintenance later in life. Maturation was strongly influenced by all three variables, with no reproduction observed in the presence of two or more environmental stressors. We found a strong interaction between As and dietary P, with increased P-supply intensifing the toxicity effect of As. No such effects were seen between As and food quantity, indicating a differential role of quantity versus quality on As toxicity. We found a nominal effect of diet on somatic As accumulation. The results from the present study emphasize the importance of considering such interactions between co-occurring environmental stressors and the dietary status of organisms, to better predict and manage impacts and risks associated with common environmental toxicants in highly vulnerable ecosystems. Environ Toxicol Chem 2024;00:1-13. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

2.
Mol Cancer Ther ; 23(6): 877-889, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38593239

RESUMO

Head and neck cancer radiotherapy often damages salivary glands and oral mucosa, severely negatively impacting patients' quality of life. The ability of FLASH proton radiotherapy (F-PRT) to decrease normal tissue toxicity while maintaining tumor control compared with standard proton radiotherapy (S-PRT) has been previously demonstrated for several tissues. However, its potential in ameliorating radiation-induced salivary gland dysfunction and oral mucositis and controlling orthotopic head and neck tumor growth has not been reported. The head and neck area of C57BL/6 mice was irradiated with a single dose of radiotherapy (ranging from 14-18 Gy) or a fractionated dose of 8 Gy × 3 of F-PRT (128 Gy/second) or S-PRT (0.95 Gy/second). Following irradiation, the mice were studied for radiation-induced xerostomia by measuring their salivary flow. Oral mucositis was analyzed by histopathologic examination. To determine the ability of F-PRT to control orthotopic head and neck tumors, tongue tumors were generated in the mice and then irradiated with either F-PRT or S-PRT. Mice treated with either a single dose or fractionated dose of F-PRT showed significantly improved survival than those irradiated with S-PRT. F-PRT-treated mice showed improvement in their salivary flow. S-PRT-irradiated mice demonstrated increased fibrosis in their tongue epithelium. F-PRT significantly increased the overall survival of the mice with orthotopic tumors compared with the S-PRT-treated mice. The demonstration that F-PRT decreases radiation-induced normal tissue toxicity without compromising tumor control, suggests that this modality could be useful for the clinical management of patients with head and neck cancer.


Assuntos
Modelos Animais de Doenças , Neoplasias de Cabeça e Pescoço , Terapia com Prótons , Glândulas Salivares , Estomatite , Animais , Camundongos , Estomatite/etiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Glândulas Salivares/efeitos da radiação , Glândulas Salivares/patologia , Terapia com Prótons/métodos , Humanos , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Xerostomia/etiologia , Feminino
3.
bioRxiv ; 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38014072

RESUMO

The global aquaculture industry has grown substantially, with consequences for coastal ecology and biogeochemistry. Oyster aquaculture can alter the availability of resources for microbes that live in sediments as oysters move large quantities of organic material to the sediments via filter feeding, possibly leading to changes in the structure and function of sediment microbial communities. Here, we use a chronosequence approach to investigate the impacts of oyster farming on sediment microbial communities over 7 years of aquaculture activity in a temperate coastal system. We detected shifts in bacterial composition (16S rRNA amplicon sequencing), changes in gene expression (meta-transcriptomics), and variations in sediment elemental concentrations (sediment geochemistry) across different durations of oyster farming. Our results indicate that both the structure and function of bacterial communities vary between control (no oysters) and farm sites, with an overall increase in diversity and a shift towards anoxic tolerance in farm sites. However, little to no variation was observed in either structure or function with respect to farming duration suggesting these sediment microbial communities are resilient to change. We also did not find any significant impact of farming on heavy metal accumulation in the sediments. The minimal influence of long-term oyster farming on sediment bacterial function and biogeochemical processes as observed here can bear important consequences for establishing best practices for sustainable farming in these areas. Importance: Sediment microbial communities drive a range of important ecosystem processes such as nutrient recycling and filtration. Oysters are well-known ecological engineers, and their presence is increasing as aquaculture expands in coastal waters globally. Determining how oyster aquaculture impacts sediment microbial processes is key to understanding current and future estuarine biogeochemical processes. Here, we use a multi-omics approach to study the effect of different durations of oyster farming on the structure and function of bacteria and elemental accumulation in the farm sediments. Our results indicate an increase in the diversity of bacterial communities in the farm sites with no such increases observed for elemental concentrations. Further, these effects persist across multiple years of farming with an increase of anoxic tolerant bacteria at farm sites. The multi-omics approach used in this study can serve as a valuable tool to facilitate understanding of the environmental impacts of oyster aquaculture.

4.
Nat Immunol ; 24(8): 1358-1369, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37365386

RESUMO

Following infection or vaccination, activated B cells at extrafollicular sites or within germinal centers (GCs) undergo vigorous clonal proliferation. Proliferating lymphocytes have been shown to undertake lactate dehydrogenase A (LDHA)-dependent aerobic glycolysis; however, the specific role of this metabolic pathway in a B cell transitioning from a naïve to a highly proliferative, activated state remains poorly defined. Here, we deleted LDHA in a stage-specific and cell-specific manner. We find that ablation of LDHA in a naïve B cell did not profoundly affect its ability to undergo a bacterial lipopolysaccharide-induced extrafollicular B cell response. On the other hand, LDHA-deleted naïve B cells had a severe defect in their capacities to form GCs and mount GC-dependent antibody responses. In addition, loss of LDHA in T cells severely compromised B cell-dependent immune responses. Strikingly, when LDHA was deleted in activated, as opposed to naïve, B cells, there were only minimal effects on the GC reaction and in the generation of high-affinity antibodies. These findings strongly suggest that naïve and activated B cells have distinct metabolic requirements that are further regulated by niche and cellular interactions.


Assuntos
Linfócitos B , Centro Germinativo , Linfócitos T , Ativação Linfocitária , Comunicação Celular
5.
Integr Cancer Ther ; 21: 15347354221128832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419372

RESUMO

BACKGROUND: Different parts of Dillenia pentagyna have long been used in traditional medicines to cure several diseases including cancer. However, the mechanism(s) of anti-cancer effects are still unknown. We aimed to elucidate the anti-metastatic potential of ethanolic extracts of leaves of D. pentagyna (EELDP) and active fractions of it in highly metastatic human cancer cells. METHODS: We screened different HPLC fractions of EELDP based on their anti-metastatic effect. We used TLC and ESI-MS for determining the presence of various phytochemicals in EELDP and fractions. We monitored in vitro anti-metastasis effect of EELDP (0-0.6 mg/ml) and active fractions (0-0.050 mg/ml) on various human cancer cells like A549, HeLa, and U2OS. RESULTS: EELDP significantly reduced cell viability and cell migration in A549, HeLa, and U2OS cells. However, higher sensitivity was observed in A549 cells. We screened 2 active HPLC fractions F6 and F8 having anti-MMPs activity. EELDP and active fractions reduced metastasis via the NF-κB pathway, decreased the expression of Vimentin, N-cadherin, and increased the expression of Claudin-1. CONCLUSION: Significant reduction of metastasis by EELDP at a dose of 0.1 mg/ml or by active fractions at 0.050 mg/ml implicates that the active compound(s) present in crude or fractions are extremely potent to control highly metastatic cancer.


Assuntos
Dilleniaceae , Neoplasias , Humanos , Dilleniaceae/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Células A549 , Movimento Celular , Neoplasias/tratamento farmacológico
6.
Front Microbiol ; 12: 666558, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512564

RESUMO

Terrestrial ecosystems are an important carbon store, and this carbon is vulnerable to microbial degradation with climate warming. After 30 years of experimental warming, carbon stocks in a temperate mixed deciduous forest were observed to be reduced by 30% in the heated plots relative to the controls. In addition, soil respiration was seasonal, as was the warming treatment effect. We therefore hypothesized that long-term warming will have higher expressions of genes related to carbohydrate and lipid metabolism due to increased utilization of recalcitrant carbon pools compared to controls. Because of the seasonal effect of soil respiration and the warming treatment, we further hypothesized that these patterns will be seasonal. We used RNA sequencing to show how the microbial community responds to long-term warming (~30 years) in Harvard Forest, MA. Total RNA was extracted from mineral and organic soil types from two treatment plots (+5°C heated and ambient control), at two time points (June and October) and sequenced using Illumina NextSeq technology. Treatment had a larger effect size on KEGG annotated transcripts than on CAZymes, while soil types more strongly affected CAZymes than KEGG annotated transcripts, though effect sizes overall were small. Although, warming showed a small effect on overall CAZymes expression, several carbohydrate-associated enzymes showed increased expression in heated soils (~68% of all differentially expressed transcripts). Further, exploratory analysis using an unconstrained method showed increased abundances of enzymes related to polysaccharide and lipid metabolism and decomposition in heated soils. Compared to long-term warming, we detected a relatively small effect of seasonal variation on community gene expression. Together, these results indicate that the higher carbohydrate degrading potential of bacteria in heated plots can possibly accelerate a self-reinforcing carbon cycle-temperature feedback in a warming climate.

7.
Immunity ; 53(5): 952-970.e11, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33098766

RESUMO

Precise targeting of activation-induced cytidine deaminase (AID) to immunoglobulin (Ig) loci promotes antibody class switch recombination (CSR) and somatic hypermutation (SHM), whereas AID targeting of non-Ig loci can generate oncogenic DNA lesions. Here, we examined the contribution of G-quadruplex (G4) nucleic acid structures to AID targeting in vivo. Mice bearing a mutation in Aicda (AIDG133V) that disrupts AID-G4 binding modeled the pathology of hyper-IgM syndrome patients with an orthologous mutation, lacked CSR and SHM, and had broad defects in genome-wide AIDG133V chromatin localization. Genome-wide analyses also revealed that wild-type AID localized to MHCII genes, and AID expression correlated with decreased MHCII expression in germinal center B cells and diffuse large B cell lymphoma. Our findings indicate a crucial role for G4 binding in AID targeting and suggest that AID activity may extend beyond Ig loci to regulate the expression of genes relevant to the physiology and pathology of activated B cells.


Assuntos
Cromatina/genética , Cromatina/metabolismo , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Quadruplex G , Síndrome de Imunodeficiência com Hiper-IgM/etiologia , Síndrome de Imunodeficiência com Hiper-IgM/metabolismo , Mutação , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biologia Computacional/métodos , Modelos Animais de Doenças , Suscetibilidade a Doenças , Ativação Enzimática , Imunofluorescência , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Antígenos HLA/genética , Antígenos HLA/imunologia , Humanos , Síndrome de Imunodeficiência com Hiper-IgM/diagnóstico , Switching de Imunoglobulina/genética , Switching de Imunoglobulina/imunologia , Imunofenotipagem , Ativação Linfocitária/genética , Linfoma Difuso de Grandes Células B/etiologia , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Transgênicos
8.
Ecol Lett ; 23(7): 1064-1072, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32301270

RESUMO

The growth rate hypothesis posits that the rate of protein synthesis is constrained by phosphorus (P) supply. P scarcity invokes differential expression of genes involved in processing of most if not all elements encompassing an individual (the ionome). Whether such ionome-wide adjustments to P supply impact growth and trophic interactions remains unclear. We quantified the ionomes of a resource-consumer pair in contrasting P supply conditions. Consumer growth penalty was driven by not only P imbalance between trophic levels but also imbalances in other elements, reflecting complex physiological adjustments made by both the resource and the consumer. Mitigating such imbalances requires energy and should impact the efficiency at which assimilated nutrients are converted to biomass. Correlated shifts in the handling of multiple elements, and variation in the supplies of such elements could underlie vast heterogeneity in the rates at which organisms and ecosystems accrue biomass as a function of P supply.


Assuntos
Daphnia , Fósforo , Animais , Biomassa , Ecossistema , Cadeia Alimentar
9.
Int J Radiat Biol ; 96(5): 651-660, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31914341

RESUMO

Purpose: Radiotherapy using gamma ray is still the main therapeutic modality for the treatment of various cancers. However, local recurrence and increase of metastasis after radiotherapy is still a major therapeutic challenge. Aim of this work was to check cell migration along with activity and expression of some marker proteins involved in epithelial-mesenchymal transition (EMT) pathway in three different human cancer cells after exposure with gamma radiation in combination with PARP inhibitor olaparib.Materials and methods: Here, we presented cell viability, in vitro cell migration, activity of MMPs by gelatin zymography, expression of few EMT marker proteins and the signaling cascade involved in transcriptional regulation of MMPs after gamma irradiation with and without olaparib pretreatment in highly metastatic three human cancer cell lines-A549, HeLa and U2OS.Results: We observed that gamma irradiation alone increased in vitro cell migration, MMP-2,-9 activity, expression of N-cadherin, vimentin and the signaling molecules EGFR, ERK1/2, Akt, p38 that enhanced NF-kB expression in all three cell types. Olaparib treatment alone reduced in vitro cell migration along with reduction of expression of all the above-mentioned marker proteins of the EMT pathway. However, 4 h olaparib pretreatment prevented gamma ray induced activation of all these marker proteins in all three cell types.Conclusions: This data implicates that olaparib treatment in combination with gamma therapy could be promising in protecting patients from gamma-induced metastasis.


Assuntos
Movimento Celular/efeitos da radiação , Raios gama , Metástase Neoplásica/prevenção & controle , Ftalazinas/farmacologia , Piperazinas/farmacologia , Células A549 , Movimento Celular/efeitos dos fármacos , Receptores ErbB/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Células HeLa , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
10.
Microbiol Resour Announc ; 8(42)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31624174

RESUMO

Little is known about the impact of oyster farming on sediment microbial communities. Here, we use 16S rRNA gene sequencing to identify bacterial communities in 24 sediment samples collected from an oyster farm in Ninigret Pond, RI. A total of 13,147 unique operational taxonomic units (OTUs) were assigned, with Proteobacteria being the dominant phyla across all samples.

11.
BMC Cancer ; 19(1): 829, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438892

RESUMO

BACKGROUND: Carbon ion (12C) radiotherapy is becoming very promising to kill highly metastatic cancer cells keeping adjacent normal cells least affected. Our previous study shows that combined PARP-1 inhibition with 12C ion reduces MMP-2,-9 synergistically in HeLa cells but detailed mechanism are not clear. To understand this mechanism and the rationale of using PARP-1 inhibitor with 12C ion radiotherapy for better outcome in controlling metastasis, we investigated metastatic potential in two non-small cell lung cancer (NSCLC) A549 and H1299 (p53-deficient) cells exposed with 12C ion in presence and absence of PARP-1 inhibition using siRNA or olaparib. METHODS: We monitored cell proliferation, in-vitro cell migration, wound healing, expression and activity of MMP-2, - 9 in A549 and p53-deficient H1299 cell lines exposed with 12C ion with and without PARP-1 inhibitor olaparib/DPQ. Expression and phosphorylation of NF-kB, EGFR, Akt, p38, ERK was also observed in A549 and H1299 cells exposed with 12C ion with and without PARP-1 inhibition using siRNA or olaparib. We also checked expression of few marker genes involved in epithelial-mesenchymal transition (EMT) pathways like N-cadherin, vimentin, anillin, claudin-1, - 2 in both NSCLC. To determine the generalized effect of 12C ion and olaparib in inhibition of cell's metastatic potential, wound healing and activity of MMP-2, - 9 was also studied in HeLa and MCF7 cell lines after 12C ion exposure and in combination with PARP-1 inhibitor olaparib. RESULTS: Our experiments show that 12C ion and PARP-1 inhibition separately reduces cell proliferation, cell migration, wound healing, phosphorylation of EGFR, Akt, p38, ERK resulting inactivation of NF-kB. Combined treatment abolishes NF-kB expression and hence synergistically reduces MMP-2, - 9 expressions. Each single treatment reduces N-cadherin, vimentin, anillin but increases claudin-1, - 2 leading to suppression of EMT process. However, combined treatment synergistically alters these proteins to suppress EMT pathways significantly. CONCLUSION: The activation pathways of transcription of MMP-2,-9 via NF-kB and key marker proteins in EMT pathways are targeted by both 12C ion and olaparib/siRNA. Hence, 12C ion radiotherapy could potentially be combined with olaparib as chemotherapeutic agent for better control of cancer metastasis.


Assuntos
Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Tolerância a Radiação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular/genética , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Radiação Ionizante , Cicatrização , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
J Cell Biochem ; 120(12): 19841-19857, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31318086

RESUMO

Despite the advancement of the pharmaceutical industry, medicinal plants are still a reliable source of traditional medicines to cure a number of diseases. Various parts of Dillenia pentagyna are used in traditional medicine in India for treatment of various disorders including cancers, but detailed mechanisms are still unknown. Dried leaves of D. pentagyna were extracted with ethanol and termed as an ethanolic extract of leaves of D. pentagyna (EELDP). Our aim was to elucidate the role of EELDP in in-vitro cell migration and apoptosis in highly metastatic human lung adenocarcinoma A549 cells. We measured cell viability and in-vitro cell migration in three different human cancer cells A549, HeLa and U2OS treated with EELDP (0-0.6 mg/mL). However, A549 cells showed higher sensitivity to EELDP treatment. Hence we studied several key markers of metastasis and apoptosis pathway in A549 cells treated with EELDP. EELDP treatment significantly reduced in-vitro cell migration, wound healing, expression and activity of MMP-2, MMP-9 via reduction of nuclear factor kappa Beta (NF-κß). EELDP also reduced vimentin, N-cadherin and increased claudin-1. The intrinsic pathway of apoptosis was triggered by EELDP via the NF-κß pathway through the increase of the Bax to Bcl2 ratio, leading to the fall of mitochondrial membrane potential and subsequently induced release of cytochrome c, activation of caspase-3 followed by nuclear fragmentation in A549 cells. Furthermore, we observed change of a few markers of metastasis and apoptosis in other two cell types HeLa and U2OS treated with EELDP. These data implicate that the effect of EELDP is not cell-specific. Since only 0.1 mg/mL EELDP significantly reduces in-vitro cell migration and increases apoptosis, the active compound(s) present in EELDP is very much potent to control highly metastatic cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Dilleniaceae/química , Extratos Vegetais/farmacologia , Células A549 , Antineoplásicos Fitogênicos/química , Apoptose/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Regulação para Baixo/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , NF-kappa B/metabolismo , Nitrilas/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais/química , Espécies Reativas de Oxigênio/metabolismo , Sulfonas/farmacologia
13.
Cell Rep ; 27(5): 1472-1486.e5, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31042474

RESUMO

The immunoglobulin heavy chain (Igh) locus features a dynamic chromatin landscape to promote class switch recombination (CSR), yet the mechanisms that regulate this landscape remain poorly understood. CHD4, a component of the chromatin remodeling NuRD complex, directly binds H3K9me3, an epigenetic mark present at the Igh locus during CSR. We find that CHD4 is essential for early B cell development but is dispensable for the homeostatic maintenance of mature, naive B cells. However, loss of CHD4 in mature B cells impairs CSR because of suboptimal targeting of AID to the Igh locus. Additionally, we find that CHD4 represses p53 expression to promote B cell proliferation. This work reveals distinct roles for CHD4 in B cell development and CSR and links the H3K9me3 epigenetic mark with AID recruitment to the Igh locus.


Assuntos
Linfócitos B/imunologia , Proliferação de Células , DNA Helicases/genética , Switching de Imunoglobulina , Animais , Linfócitos B/citologia , Linfócitos B/fisiologia , Diferenciação Celular , Células Cultivadas , Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Genes de Cadeia Pesada de Imunoglobulina , Camundongos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
14.
R Soc Open Sci ; 5(3): 172193, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29657812

RESUMO

Understanding how populations adapt to rising temperatures has been a challenge in ecology. Research often evaluates multiple populations to test whether local adaptation to temperature regimes is occurring. Space-for-time substitutions are common, as temporal constraints limit our ability to observe evolutionary responses. We employed a resurrection ecology approach to understand how thermal tolerance has changed in a Daphnia pulicaria population over time. Temperatures experienced by the oldest genotypes were considerably lower than the youngest. We hypothesized clones were adapted to the thermal regimes of their respective time periods. We performed two thermal shock experiments that varied in length of heat exposure. Overall trends revealed that younger genotypes exhibited higher thermal tolerance than older genotypes; heat shock protein (hsp70) expression increased with temperature and varied among genotypes, but not across time periods. Our results indicate temperature may have been a selective factor on this population, although the observed responses may be a function of multifarious selection. Prior work found striking changes in population genetic structure, and in other traits that were strongly correlated with anthropogenic changes. Resurrection ecology approaches should help our understanding of interactive effects of anthropogenic alterations to temperature and other stressors on the evolutionary fate of natural populations.

15.
Cell Biochem Biophys ; 76(1-2): 311-319, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29134494

RESUMO

Telomere DNA can form specialized nucleoprotein structure with telomere-associated proteins to hide free DNA ends or G-quadruplex structures under certain conditions especially in presence of G-quadruplex ligand. Telomere DNA is transcribed to form non-coding telomere repeat-containing RNA (TERRA) whose biogenesis and function is poorly understood. Our aim was to find the role of telomere-associated proteins and telomere structures in TERRA transcription. We silenced four [two shelterin (TRF1, TRF2) and two non-shelterin (PARP-1, SLX4)] telomere-associated genes using siRNA and verified depletion in protein level. Knocking down of one gene modulated expression of other telomere-associated genes and increased TERRA from 10q, 15q, XpYp and XqYq chromosomes in A549 cells. Telomere was destabilized or damaged by G-quadruplex ligand pyridostatin (PDS) and bleomycin. Telomere dysfunction-induced foci (TIFs) were observed for each case of depletion of proteins, treatment with PDS or bleomycin. TERRA level was elevated by PDS and bleomycin treatment alone or in combination with depletion of telomere-associated proteins.


Assuntos
RNA Longo não Codificante/metabolismo , Telômero/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Células A549 , Bleomicina/farmacologia , Quadruplex G , Humanos , Hibridização in Situ Fluorescente , Microscopia de Fluorescência , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Interferência de RNA , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Recombinases/antagonistas & inibidores , Recombinases/genética , Recombinases/metabolismo , Telômero/química , Proteína 1 de Ligação a Repetições Teloméricas/antagonistas & inibidores , Proteína 1 de Ligação a Repetições Teloméricas/genética , Proteína 2 de Ligação a Repetições Teloméricas/antagonistas & inibidores , Proteína 2 de Ligação a Repetições Teloméricas/genética , Regulação para Cima/efeitos dos fármacos
16.
J Clin Diagn Res ; 11(8): GR01-GR06, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28969156

RESUMO

Congenital limb anomalies are outcome of improper bone formation during embryonic development when cells divide, differentiate with high rate. So, telomerase activity is essential to maintain telomere length for such highly dividing cells. Here, we report four cases of congenital limb anomalies with detailed structures of limbs along with other clinical manifestations of age less than two years. We compared telomere length, expression of telomerase and telomere-associated genes of Peripheral Blood Mononuclear Cells (PBMC) in patient and four age-matched normal individual. Patient-1 was diagnosed with congenital limb hypogenesis ectrodactyly sequence, an autosomal dominant disorder, showing absence of digits and fibula in upper and lower limb respectively. Both mother and grandmother of Patient-1 showed similar hypogenesis of limbs. Patient-2 showed bilateral clenched hand with arthrogryposis, microcephaly and holoprosencephaly. Both Patient-3 and Patient-4 has no radius in upper limb. Additionally, Paient-3 showed right sided orbital Space Occupying Lesion (SOL) and Paranasal Sinuses (PNS) whereas Patient-4 showed fused kidney with fanconi anaemia. Furthermore, all the patients showed shorter telomere length, inactive telomerase and de-regulated expression of telomere-associated proteins in PBMC compared with age-matched control group. So, we can conclude that congenital limb anomalies may be linked with telomeropathy and a study with large number of samples is required to firmly establish such association.

17.
R Soc Open Sci ; 4(12): 170770, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29308224

RESUMO

The framework ecological stoichiometry uses elemental composition of species to make predictions about growth and competitive ability in defined elemental supply conditions. Although intraspecific differences in stoichiometry have been observed, we have yet to understand the mechanisms generating and maintaining such variation. We used variation in phosphorus (P) content within a Daphnia species to test the extent to which %P can explain variation in growth and competition. Further, we measured 33P kinetics (acquisition, assimilation, incorporation and retention) to understand the extent to which such variables improved predictions. Genotypes showed significant variation in P content, 33P kinetics and growth rate. P content alone was a poor predictor of growth rate and competitive ability. While most genotypes exhibited the typical growth penalty under P limitation, a few varied little in growth between P diets. These observations indicate that some genotypes can maintain growth under P-limited conditions by altering P use, suggesting that decomposing P content of an individual into physiological components of P kinetics will improve stoichiometric models. More generally, attention to the interplay between nutrient content and nutrient-use is required to make inferences regarding the success of genotypes in defined conditions of nutrient supply.

18.
Radiat Oncol ; 11(1): 126, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27659937

RESUMO

BACKGROUND: Hadron therapy is an innovative technique where cancer cells are precisely killed leaving surrounding healthy cells least affected by high linear energy transfer (LET) radiation like carbon ion beam. Anti-metastatic effect of carbon ion exposure attracts investigators into the field of hadron biology, although details remain poor. Poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors are well-known radiosensitizer and several PARP-1 inhibitors are in clinical trial. Our previous studies showed that PARP-1 depletion makes the cells more radiosensitive towards carbon ion than gamma. The purpose of the present study was to investigate combining effects of PARP-1 inhibition with carbon ion exposure to control metastatic properties in HeLa cells. METHODS: Activities of matrix metalloproteinases-2, 9 (MMP-2, MMP-9) were measured using the gelatin zymography after 85 MeV carbon ion exposure or gamma irradiation (0- 4 Gy) to compare metastatic potential between PARP-1 knock down (HsiI) and control cells (H-vector - HeLa transfected with vector without shRNA construct). Expression of MMP-2, MMP-9, tissue inhibitor of MMPs such as TIMP-1, TIMP-2 and TIMP-3 were checked by immunofluorescence and western blot. Cell death by trypan blue, apoptosis and autophagy induction were studied after carbon ion exposure in each cell-type. The data was analyzed using one way ANOVA and 2-tailed paired-samples T-test. RESULTS: PARP-1 silencing significantly reduced MMP-2 and MMP-9 activities and carbon ion exposure further diminished their activities to less than 3 % of control H-vector. On the contrary, gamma radiation enhanced both MMP-2 and MMP-9 activities in H-vector but not in HsiI cells. The expression of MMP-2 and MMP-9 in H-vector and HsiI showed different pattern after carbon ion exposure. All three TIMPs were increased in HsiI, whereas only TIMP-1 was up-regulated in H-vector after irradiation. Notably, the expressions of all TIMPs were significantly higher in HsiI than H-vector at 4 Gy. Apoptosis was the predominant mode of cell death and no autophagic death was observed. CONCLUSIONS: Our study demonstrates for the first time that PARP-1 inhibition in combination with carbon ion synergistically decreases MMPs activity along with overall increase of TIMPs. These data open up the possibilities of improvement of carbon ion therapy with PARP-1 inhibition to control highly metastatic cancers.

19.
Int J Environ Res Public Health ; 13(2): 215, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26891310

RESUMO

Arsenic contamination in drinking water has a detrimental impact on human health which profoundly impairs the quality of life. Despite recognition of the adverse health implications of arsenic toxicity, there have been few studies to date to suggest measures that could be taken to overcome arsenic contamination. After the statement in 2000 WHO Bulletin that Bangladesh has been experiencing the largest mass poisoning of population in history, we researched existing literature to assess the magnitude of groundwater arsenic contamination in Bangladesh. The literature reviewed related research that had been initiated and/or completed since the implementation of the Millennium Development Goals (MDGs) under four domains: (1) extent of arsenic contamination; (2) health consequences; (3) mitigation and technologies and (4) future directions. To this means, a review matrix was established for analysis of previous literature based on these four core domains. Our findings revealed that several high-quality research articles were produced at the beginning of the MDG period, but efforts have dwindled in recent years. Furthermore, there were only a few studies conducted that focused on developing suitable solutions for managing arsenic contamination. Although the government of Bangladesh has made its population's access to safe drinking water a priority agenda item, there are still pockets of the population that continue to suffer from arsenic toxicity due to contaminated water supplies.


Assuntos
Arsênio/análise , Água Potável/química , Água Subterrânea/química , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Arsênio/toxicidade , Intoxicação por Arsênico/epidemiologia , Intoxicação por Arsênico/etiologia , Intoxicação por Arsênico/prevenção & controle , Bangladesh/epidemiologia , Monitoramento Ambiental , Humanos , Qualidade de Vida , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/efeitos adversos , Poluição Química da Água/análise , Poluição Química da Água/prevenção & controle
20.
Mol Ecol ; 24(1): 123-35, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25410011

RESUMO

Little is known about the role of transcriptomic changes in driving phenotypic evolution in natural populations, particularly in response to anthropogenic environmental change. Previous analyses of Daphnia genotypes separated by centuries of evolution in a lake using methods in resurrection ecology revealed striking genetic and phenotypic shifts that were highly correlated with anthropogenic environmental change, specifically phosphorus (P)-driven nutrient enrichment (i.e. eutrophication). Here, we compared the transcriptomes of two ancient (~700-year-old) and two modern (~10-year-old) genotypes in historic (low P) and contemporary (high P) environmental conditions using microarrays. We found considerable transcriptomic variation between 'ancient' and 'modern' genotypes in both treatments, with stressful (low P) conditions eliciting differential expression (DE) of a larger number of genes. Further, more genes were DE between 'ancient' and 'modern' genotypes than within these groups. Expression patterns of individual genes differed greatly among genotypes, suggesting that different transcriptomic responses can result in similar phenotypes. While this confounded patterns between 'ancient' and 'modern' genotypes at the gene level, patterns were discernible at the functional level: annotation of DE genes revealed particular enrichment of genes involved in metabolic pathways in response to P-treatments. Analyses of gene families suggested significant DE in pathways already known to be important in dealing with P-limitation in Daphnia as well as in other organisms. Such observations on genotypes of a single natural population, separated by hundreds of years of evolution in contrasting environmental conditions before and during anthropogenic environmental changes, highlight the important role of transcriptional mechanisms in the evolutionary responses of populations.


Assuntos
Daphnia/genética , Genética Populacional , Genótipo , Fósforo/química , Transcriptoma , Animais , Evolução Molecular , Lagos/química , Anotação de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo
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