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1.
PLoS Genet ; 20(7): e1011036, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38968323

RESUMO

Replicated clines across environmental gradients can be strong evidence of adaptation. House mice (Mus musculus domesticus) were introduced to the Americas by European colonizers and are now widely distributed from Tierra del Fuego to Alaska. Multiple aspects of climate, such as temperature, vary predictably across latitude in the Americas. Past studies of North American populations across latitudinal gradients provided evidence of environmental adaptation in traits related to body size, metabolism, and behavior and identified candidate genes using selection scans. Here, we investigate genomic signals of environmental adaptation on a second continent, South America, and ask whether there is evidence of parallel adaptation across multiple latitudinal transects in the Americas. We first identified loci across the genome showing signatures of selection related to climatic variation in mice sampled across a latitudinal transect in South America, accounting for neutral population structure. Consistent with previous results, most candidate SNPs were in putatively regulatory regions. Genes that contained the most extreme outliers relate to traits such as body weight or size, metabolism, immunity, fat, eye function, and the cardiovascular system. We then compared these results with the results of analyses of published data from two transects in North America. While most candidate genes were unique to individual transects, we found significant overlap among candidate genes identified independently in the three transects. These genes are diverse, with functions relating to metabolism, immunity, cardiac function, and circadian rhythm, among others. We also found parallel shifts in allele frequency in candidate genes across latitudinal gradients. Finally, combining data from all three transects, we identified several genes associated with variation in body weight. Overall, our results provide strong evidence of shared responses to selection and identify genes that likely underlie recent environmental adaptation in house mice across North and South America.


Assuntos
Adaptação Fisiológica , Polimorfismo de Nucleotídeo Único , Seleção Genética , Animais , Camundongos , Adaptação Fisiológica/genética , América do Sul , Genômica/métodos , Genoma , América , Peso Corporal/genética , Genética Populacional
2.
Extremophiles ; 28(3): 31, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020126

RESUMO

The present study investigates the low temperature tolerance strategies of thermophilic bacterium Anoxybacillus rupiensis TPH1, which grows optimally at 55 °C , by subjecting it to a temperature down-shift of 10 °C (45 °C) for 4 and 6 h followed by studying its growth, morphophysiological, molecular and proteomic responses. Results suggested that although TPH1 experienced increased growth inhibition, ROS production, protein oxidation and membrane disruption after 4 h of incubation at 45 °C yet maintained its DNA integrity and cellular structure through the increased expression of DNA damage repair and cell envelop synthesizing proteins and also progressively alleviated growth inhibition by 20% within two hours i.e., 6 h, by inducing the expression of antioxidative enzymes, production of unsaturated fatty acids, capsular and released exopolysaccharides and forming biofilm along with chemotaxis proteins. Conclusively, the adaptation of Anoxybacillus rupiensis TPH1 to lower temperature is mainly mediated by the synthesis of large numbers of defense proteins and exopolysaccharide rich biofilm formation.


Assuntos
Adaptação Fisiológica , Anoxybacillus , Proteínas de Bactérias , Anoxybacillus/metabolismo , Anoxybacillus/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Temperatura Baixa , Biofilmes/crescimento & desenvolvimento
3.
Bull Math Biol ; 86(8): 100, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958824

RESUMO

Establishing a mapping between the emergent biological properties and the repository of network structures has been of great relevance in systems and synthetic biology. Adaptation is one such biological property of paramount importance that promotes regulation in the presence of environmental disturbances. This paper presents a nonlinear systems theory-driven framework to identify the design principles for perfect adaptation with respect to external disturbances of arbitrary magnitude. Based on the prior information about the network, we frame precise mathematical conditions for adaptation using nonlinear systems theory. We first deduce the mathematical conditions for perfect adaptation for constant input disturbances. Subsequently, we translate these conditions to specific necessary structural requirements for adaptation in networks of small size and then extend to argue that there exist only two classes of architectures for a network of any size that can provide local adaptation in the entire state space, namely, incoherent feed-forward (IFF) structure and negative feedback loop with buffer node (NFB). The additional positiveness constraints further narrow the admissible set of network structures. This also aids in establishing the global asymptotic stability for the steady state given a constant input disturbance. The proposed method does not assume any explicit knowledge of the underlying rate kinetics, barring some minimal assumptions. Finally, we also discuss the infeasibility of certain IFF networks in providing adaptation in the presence of downstream connections. Moreover, we propose a generic and novel algorithm based on non-linear systems theory to unravel the design principles for global adaptation. Detailed and extensive simulation studies corroborate the theoretical findings.


Assuntos
Adaptação Fisiológica , Conceitos Matemáticos , Modelos Biológicos , Dinâmica não Linear , Biologia de Sistemas , Adaptação Fisiológica/fisiologia , Simulação por Computador , Retroalimentação Fisiológica , Biologia Sintética , Teoria de Sistemas , Cinética
4.
J Phys Chem B ; 128(28): 6838-6852, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38960927

RESUMO

One of the routes for adaptation to extreme environments is via remodeling of cell membrane structure, composition, and biophysical properties rendering a functional membrane. Collective studies suggest some form of membrane feedback in mycobacterial species that harbor complex lipids within the outer and inner cell wall layers. Here, we study the homeostatic membrane landscape of mycobacteria in response to high hydrostatic pressure and temperature triggers using high pressure fluorescence, mass and infrared spectroscopies, NMR, SAXS, and molecular dynamics simulations. Our findings reveal that mycobacterial membrane possesses unique and lipid-specific pressure-induced signatures that attenuate progression to highly ordered phases. Both inner and outer membrane layers exhibit phase coexistence of nearly identical lipid phases keeping residual fluidity over a wide range of temperature and pressure, but with different sensitivities. Lipidomic analysis of bacteria grown under pressure revealed lipidome remodeling in terms of chain length, unsaturation, and specific long-chained characteristic mycobacterial lipids, rendering a fluid bacterial membrane. These findings could help understand how bacteria may adapt to a broad spectrum of harsh environments by modulating their lipidome to select lipids that enable the maintenance of a fluid functional cell envelope.


Assuntos
Membrana Celular , Fluidez de Membrana , Simulação de Dinâmica Molecular , Membrana Celular/química , Membrana Celular/metabolismo , Temperatura , Parede Celular/metabolismo , Parede Celular/química , Adaptação Fisiológica , Pressão Hidrostática , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo
5.
Nat Commun ; 15(1): 5672, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971805

RESUMO

While the underlying genetic changes have been uncovered in some cases of adaptive evolution, the lack of a systematic study prevents a general understanding of the genomic basis of adaptation. For example, it is unclear whether protein-coding or noncoding mutations are more important to adaptive evolution and whether adaptations to different environments are brought by genetic changes distributed in diverse genes and biological processes or concentrated in a core set. We here perform laboratory evolution of 3360 Saccharomyces cerevisiae populations in 252 environments of varying levels of stress. We find the yeast adaptations to be primarily fueled by large-effect coding mutations overrepresented in a relatively small gene set, despite prevalent antagonistic pleiotropy across environments. Populations generally adapt faster in more stressful environments, partly because of greater benefits of the same mutations in more stressful environments. These and other findings from this model eukaryote help unravel the genomic principles of environmental adaptation.


Assuntos
Adaptação Fisiológica , Mutação , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Adaptação Fisiológica/genética , Estresse Fisiológico/genética , Genoma Fúngico , Meio Ambiente , Evolução Molecular , Loci Gênicos , Pleiotropia Genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
Wiad Lek ; 77(5): 950-956, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39008582

RESUMO

OBJECTIVE: Aim: To conduct a structural analysis of cardiological signs of adaptation to stressogenic cognitive loads by identifying factor features of correlations between heart rate variability (HRV) and coping-testing data indicators. PATIENTS AND METHODS: Materials and Methods: 43 people aged 19.7±1.8 years (23 boys and 20 girls) were monitored for their HRV. Methods included DC-06000 portable ECG recorder, 3X series "badge" type (single channel) and COPE Test. The study process includes four stages. RESULTS: Results: As a result of further factor correlation analysis, it was revealed that Factor 1 "HRV Stress Indicators" has a negative correlation (p<0.05) of "moderate" strength ρs= -0.363 with Factor 2 "Strategies to avoid problems and stresses" and a positive correlation of "weak" strength ρs=0.167 with Factor 3 "Psychoemotional Indicators". If two factors correlate with each other, it indicates they are related and can interact, which is important for adequate interpretation of the results of factor analysis. CONCLUSION: Conclusions: Structural analysis of the complex of cardiological signs of adaptivity to stressogenic cognitive loads and coping-testing data revealed the existence of three correlated factors: Factor 1 "HRV Stress Scores", Factor 2 "Strategies to avoid problems and stress", Factor 3 "Psychoemotional indicators". The revealed negative correlation of Factors 1 and 2 may indicate that in case the impact of Factor 2 "Strategies to avoid problems and stress" increases, the intensity of Factor 1 "HRV Stress Scores" (i.e., stress signs according to the indicators of heart rate variability) may decrease.


Assuntos
Adaptação Psicológica , Frequência Cardíaca , Estresse Psicológico , Humanos , Feminino , Masculino , Frequência Cardíaca/fisiologia , Adulto Jovem , Prognóstico , Adaptação Fisiológica , Adulto , Cognição/fisiologia , Sistema Cardiovascular/fisiopatologia
7.
Commun Biol ; 7(1): 866, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009734

RESUMO

Mycobacteria adapt to infection stresses by entering a reversible non-replicating persistence (NRP) with slow or no cell growth and broad antimicrobial tolerance. Hypoxia and nutrient deprivation are two well-studied stresses commonly used to model the NRP, yet little is known about the molecular differences in mycobacterial adaptation to these distinct stresses that lead to a comparable NRP phenotype. Here we performed a multisystem interrogation of the Mycobacterium bovis BCG (BCG) starvation response, which revealed a coordinated metabolic shift away from the glycolysis of nutrient-replete growth to depletion of lipid stores, lipolysis, and fatty acid ß-oxidation in NRP. This contrasts with BCG's NRP hypoxia response involving a shift to cholesterol metabolism and triglyceride storage. Our analysis reveals cryptic metabolic vulnerabilities of the starvation-induced NRP state, such as their newfound hypersensitivity to H2O2. These observations pave the way for developing precision therapeutics against these otherwise drug refractory pathogens.


Assuntos
Adaptação Fisiológica , Mycobacterium bovis , Mycobacterium bovis/metabolismo , Glicólise , Reprogramação Metabólica
8.
Commun Biol ; 7(1): 863, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009753

RESUMO

Genetic admixture introduces new variants at relatively high frequencies, potentially aiding rapid responses to environmental changes. Here, we evaluate its role in adaptive variation related to climatic conditions in bank voles (Clethrionomys glareolus) in Britain, using whole-genome data. Our results reveal loci showing excess ancestry from one of the two postglacial colonist populations inconsistent with overall admixture patterns. Notably, loci associated with climate adaptation exhibit disproportionate amounts of excess ancestry, highlighting the impact of admixture between colonist populations on local adaptation. The results suggest strong and localized selection on climate-adaptive loci, as indicated by steep clines and/or shifted cline centres, during population replacement. A subset, including a haemoglobin gene, is associated with oxidative stress responses, underscoring a role of oxidative stress in local adaptation. Our study highlights the important contribution of admixture during secondary contact between populations from distinct climatic refugia enriching adaptive diversity. Understanding these dynamics is crucial for predicting future adaptive capacity to anthropogenic climate change.


Assuntos
Arvicolinae , Mudança Climática , Animais , Arvicolinae/genética , Arvicolinae/fisiologia , Adaptação Fisiológica/genética , Variação Genética , Aclimatação/genética , Reino Unido , Genética Populacional , Clima , Polimorfismo de Nucleotídeo Único
9.
BMC Plant Biol ; 24(1): 675, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009992

RESUMO

Responses of turfgrass to shade vary in individual species, and the degree and quality of low light; therefore, the selection of low light tolerant cultivars of turfgrass is important and beneficial for turf management rather than other practices. The stolons of thirteen bermudagrass genotypes were planted with two treatments and three replications of each treatment to establish for one month in the Yangzhou University Jiangsu China greenhouse. The established plants were transferred outside of the greenhouse, and 50% shading was applied to them with a black net. After 30 days of stress treatment, the morpho-physiological and biochemical analyses were performed. The expression of genes such as HEMA, HY5, PIF4, and Cu/ZnSOD was assessed. Cynodon dactylon is a C4, and perennial that grows as lawn grass and is used as forage. Based on different indicator measurements, the most shade-tolerant germplasm was L01 and L06 along the longitudes and L09 and L10 along the latitudes. At the same time, L02 and L08 were more susceptible, respectively. However, germplasm showed greater tolerance in higher latitudes while longitudinal plants showed less stress response. The current study aimed (1) to screen out the most shade-tolerant Cynodon dactylon genotype among 13 along longitudinal and latitudinal gradients in China. (2) to examine morpho-physiological indicators of different bermudagrassgenotypes; (3) to evaluate if and how differences in various indicators of bermudagrass correlated with geographic region. This study will significantly advance the use of Cynodon germplasm in breeding, genomics, management, nomenclature, and phylogeographical study. It will decisively define whether natural selection and migration can drive evolutionary responses for populations to adapt to their new environments effectively.


Assuntos
Cynodon , Cynodon/genética , Cynodon/fisiologia , China , Genótipo , Adaptação Fisiológica/genética
10.
J Clin Invest ; 134(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38950317

RESUMO

Glucose plays a key role in shaping pancreatic ß cell function. Thus, deciphering the mechanisms by which this nutrient stimulates ß cells holds therapeutic promise for combating ß cell failure in type 2 diabetes (T2D). ß Cells respond to hyperglycemia in part by rewiring their mRNA metabolism, yet the mechanisms governing these changes remain poorly understood. Here, we identify a requirement for the RNA-binding protein PCBP2 in maintaining ß cell function basally and during sustained hyperglycemic challenge. PCBP2 was induced in primary mouse islets incubated with elevated glucose and was required to adapt insulin secretion. Transcriptomic analysis of primary Pcbp2-deficient ß cells revealed impacts on basal and glucose-regulated mRNAs encoding core components of the insulin secretory pathway. Accordingly, Pcbp2-deficient ß cells exhibited defects in calcium flux, insulin granule ultrastructure and exocytosis, and the amplification pathway of insulin secretion. Further, PCBP2 was induced by glucose in primary human islets, was downregulated in islets from T2D donors, and impacted genes commonly altered in islets from donors with T2D and linked to single-nucleotide polymorphisms associated with T2D. Thus, these findings establish a paradigm for PCBP2 in governing basal and glucose-adaptive gene programs critical for shaping the functional state of ß cells.


Assuntos
Diabetes Mellitus Tipo 2 , Glucose , Células Secretoras de Insulina , Insulina , Proteínas de Ligação a RNA , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Camundongos , Humanos , Glucose/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Insulina/metabolismo , Secreção de Insulina , Camundongos Knockout , Masculino , Adaptação Fisiológica
11.
Sci Rep ; 14(1): 15001, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951618

RESUMO

Daylight saving time (DST) is currently utilized in many countries with the rationale that it enhances the alignment between daylight hours and activity peaks in the population. The act of transitioning into and out of DST introduces disruptions to the circadian rhythm, thereby impacting sleep and overall health. Despite the substantial number of individuals affected, the consequences of this circadian disruption have often been overlooked. Here, we employ a mathematical model of the human circadian pacemaker to elucidate how the biological clock interacts with daytime and evening exposures to both natural and electrical light. This interaction plays a crucial role in determining the adaptation to the 1 hour time zone shift imposed by the transition to or from DST. In global discussions about DST, there is a prevailing assumption that individuals easily adjust to DST transitions despite a few studies indicating that the human circadian system requires several days to fully adjust to a DST transition. Our study highlights that evening light exposure changes can be the main driving force for re-entrainment, with chronobiological models predicting that people with longer intrinsic period (i.e. later chronotype) entrain more slowly to transitions to or from DST as compared to people with a shorter intrinsic period (earlier chronotype). Moreover, the model forecasts large inter-individual differences in the adaptation speed, in particular during the spring transition. The predictions derived from our model offer circadian biology-based recommendations for light exposure strategies that facilitate a more rapid adaptation to DST-related transitions or travel across a single time zone. As such, our study contributes valuable insights to the ongoing discourse on DST and its implications for human circadian rhythms.


Assuntos
Ritmo Circadiano , Fotoperíodo , Humanos , Ritmo Circadiano/fisiologia , Luz , Sono/fisiologia , Modelos Teóricos , Adaptação Fisiológica , Relógios Biológicos/fisiologia , Relógios Circadianos/fisiologia , Modelos Biológicos
12.
PLoS One ; 19(7): e0305067, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985810

RESUMO

Falls in older individuals often result from unexpected balance disturbances during walking, necessitating the analysis of recovery strategies for effective falls prevention. This becomes particularly crucial for individuals with cognitive impairment, who face a higher fall risk compared to cognitively healthy adults. Hence, our study aimed to compare the recovery response to standardized walking perturbations on a treadmill between older adults with cognitive impairment and cognitively healthy older adults. 36 individuals with a recent history of a severe fall, leading to an emergency department visit without subsequent admission, were stratified into two groups (with and without probable cognitive impairment) based on scores of the Montreal Cognitive Assessment. Recovery performance was quantified using force plate data from a perturbation treadmill (M-Gait, Motek Medical B.V., Amsterdam, the Netherlands), specifically evaluating the number of steps needed to restore step length and width to pre perturbation baseline across two trials of nine different perturbations. Individuals with cognitive impairment (n = 18, mean age: 74.7) required significantly (p = 0.045, Cohen's d = 0.69) more steps to recover total steps after perturbations compared to cognitively healthy individuals (n = 18, mean age: 69.7). While step width recovery was similar between the groups, those with probable cognitive impairment required significantly more steps to recover their step length (p = 0.039, Cohen's d = 0.72). Thus, our findings indicate that older adults with probable cognitive impairment manifest inferior gait adaptability, especially in adapting step length, potentially underscoring a critical aspect for effective falls prevention in this population.


Assuntos
Acidentes por Quedas , Disfunção Cognitiva , Equilíbrio Postural , Humanos , Acidentes por Quedas/prevenção & controle , Idoso , Masculino , Feminino , Equilíbrio Postural/fisiologia , Disfunção Cognitiva/fisiopatologia , Idoso de 80 Anos ou mais , Marcha/fisiologia , Caminhada/fisiologia , Adaptação Fisiológica/fisiologia , Teste de Esforço
13.
Funct Plant Biol ; 512024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38991103

RESUMO

Heliotropium thermophilum (Boraginaceae) plants have strong antioxidant properties. This study investigated the effectiveness of the antioxidant system in protecting the photosynthetic machinery of H. thermophilum . Plants were obtained from Kizildere geothermal area in Buharkent district, Aydin, Turkey. Plants in the geothermal area that grew at 25-35°C were regarded as the low temperature group, while those that grew at 55-65°C were regarded as the high temperature group. We analysed the physiological changes of these plants at the two temperature conditions at stage pre-flowering and flowering. We meaured the effect of high soil temperature on water potential, malondialdehyde, cell membrane stability, and hydrogen peroxide analysis to determine stress levels on leaves and roots. Changes in antioxidant enzyme activities, ascorbate and chlorophyll content, chlorophyll fluorescence, photosynthetic gas exchange parameters, and photosynthetic enzymes (Rubisco and invertase) activities were also determined. Our results showed minimal changes to stress levels, indicating that plants were tolerant to high soil temperatures. In general, an increase in antioxidant enzyme activities, ascorbat levels, and all chlorophyll fluorescence parameters except for non-photochemical quenching (NPQ) and F v /F m were observed. The pre-flowering and flowering stages were both characterised by decreased NPQ, despite F v /F m not changing. Additionally, there was a rise in the levels of photosynthetic gas exchange parameters, Rubisco, and invertase activities. High temperature did not affect photosynthetic yield because H. thermophilum was found to stimulate antioxidant capacity, which reduces oxidative damage and maintains its photosynthetic machinery in high temperature conditions and therefore, it is tolerant to high soil temperature.


Assuntos
Antioxidantes , Heliotropium , Fotossíntese , Solo , Antioxidantes/metabolismo , Solo/química , Heliotropium/metabolismo , Clorofila/metabolismo , Folhas de Planta/metabolismo , Temperatura Alta , Adaptação Fisiológica , Turquia , Temperatura , Malondialdeído/metabolismo
14.
PLoS One ; 19(7): e0306276, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38990816

RESUMO

Being able to adapt our movements to changing circumstances allows people to maintain performance across a wide range of tasks throughout life, but it is unclear whether visuomotor learning abilities are fully developed in young children and, if so, whether they remain stable in the elderly. There is limited evidence of changes in motor adaptation ability throughout life, and the findings are inconsistent. Therefore, our goal was to compare visuomotor learning abilities throughout the lifespan. We used a shorter, gamified experimental task and collected data from participants in 5 age groups. Young children (M = 7 years), older children (M = 11 years), young adults (M = 20 years), adults (M = 40 years) and older adults (M = 67 years) adapted to a 45° visuomotor rotation in a centre-out reaching task. Across measures of rate of adaptation, extent of learning, rate of unlearning, generalization, and savings, we found that all groups performed similarly. That is, at least for short bouts of gamified learning, children and older adults perform just as well as young adults.


Assuntos
Adaptação Fisiológica , Aprendizagem , Desempenho Psicomotor , Humanos , Adulto , Idoso , Masculino , Feminino , Criança , Adulto Jovem , Aprendizagem/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Pessoa de Meia-Idade , Envelhecimento/fisiologia
15.
Physiol Rep ; 12(13): e16132, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38993022

RESUMO

Different rat strains are used in various animal models of pulmonary hypertension and right ventricular (RV) failure. No systematic assessment has been made to test differences in RV response to pressure overload between rat strains. We compared RV adaptation to pulmonary trunk banding (PTB) in Wistar (W), Sprague Dawley (SD), and Fischer344 (F) rats by hemodynamic profiling focusing on diastolic function. Age-matched male rat weanlings were randomized to sham surgery (W-sham, n = 5; SD-sham, n = 4; F-sham, n = 4) or PTB (W-PTB, n = 8; SD-PTB, n = 8; F-PTB, n = 8). RV function was evaluated after 5 weeks by echocardiography, cardiac MRI, and invasive pressure-volume measurements. PTB caused RV failure and increased RV systolic pressures four-fold in all three PTB groups compared with sham. W- and SD-PTB had a 2.4-fold increase in RV end-systolic volume index compared with sham, while F-PTB rats were less affected. Diastolic and right atrial impairment were evident by increased RV end-diastolic elastance, filling pressure, and E/e' in PTB rats compared with sham, again F-PTB the least affected. In conclusions, PTB caused RV failure with signs of diastolic dysfunction. Despite a similar increase in RV systolic pressure, F-PTB rats showed less RV dilatation and a more preserved diastolic function compared with W- and SD-PTB.


Assuntos
Adaptação Fisiológica , Diástole , Ratos Sprague-Dawley , Ratos Wistar , Função Ventricular Direita , Animais , Masculino , Ratos , Diástole/fisiologia , Função Ventricular Direita/fisiologia , Adaptação Fisiológica/fisiologia , Disfunção Ventricular Direita/fisiopatologia , Disfunção Ventricular Direita/diagnóstico por imagem , Ratos Endogâmicos F344 , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/etiologia , Ventrículos do Coração/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Especificidade da Espécie
16.
Commun Biol ; 7(1): 853, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997445

RESUMO

SAR202 bacteria in the Chloroflexota phylum are abundant and widely distributed in the ocean. Their genome coding capacities indicate their potential roles in degrading complex and recalcitrant organic compounds in the ocean. However, our understanding of their genomic diversity, vertical distribution, and depth-related metabolisms is still limited by the number of assembled SAR202 genomes. In this study, we apply deep metagenomic sequencing (180 Gb per sample) to investigate microbial communities collected from six representative depths at the Bermuda Atlantic Time Series (BATS) station. We obtain 173 SAR202 metagenome-assembled genomes (MAGs). Intriguingly, 154 new species and 104 new genera are found based on these 173 SAR202 genomes. We add 12 new subgroups to the current SAR202 lineages. The vertical distribution of 20 SAR202 subgroups shows their niche partitioning in the euphotic, mesopelagic, and bathypelagic oceans, respectively. Deep-ocean SAR202 bacteria contain more genes and exhibit more metabolic potential for degrading complex organic substrates than those from the euphotic zone. With deep metagenomic sequencing, we uncover many new lineages of SAR202 bacteria and their potential functions which greatly deepen our understanding of their diversity, vertical profile, and contribution to the ocean's carbon cycling, especially in the deep ocean.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica , Metagenômica/métodos , Oceanos e Mares , Metagenoma , Água do Mar/microbiologia , Filogenia , Genoma Bacteriano , Chloroflexi/genética , Chloroflexi/classificação , Bermudas , Adaptação Fisiológica/genética , Microbiota/genética
17.
Am Nat ; 204(2): 121-132, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39008840

RESUMO

AbstractClimate change will alter interactions between parasites and their hosts. Warming may affect patterns of local adaptation, shifting the environment to favor the parasite or host and thus changing the prevalence of disease. We assessed local adaptation to hosts and temperature in the facultative ciliate parasite Lambornella clarki, which infects the western tree hole mosquito Aedes sierrensis. We conducted laboratory infection experiments with mosquito larvae and parasites collected from across a climate gradient, pairing sympatric or allopatric populations across three temperatures that were either matched or mismatched to the source environment. Lambornella clarki parasites were locally adapted to their hosts, with 2.6 times higher infection rates on sympatric populations compared with allopatric populations, but they were not locally adapted to temperature. Infection peaked at the intermediate temperature of 12.5°C, notably lower than the optimum temperature for free-living L. clarki growth, suggesting that the host's immune response can play a significant role in mediating the outcome of infection. Our results highlight the importance of host selective pressure on parasites, despite the impact of temperature on infection success.


Assuntos
Aedes , Interações Hospedeiro-Parasita , Larva , Temperatura , Animais , Aedes/parasitologia , Larva/parasitologia , Larva/crescimento & desenvolvimento , Adaptação Fisiológica , Apicomplexa/fisiologia
18.
Function (Oxf) ; 5(4)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38984994

RESUMO

While regular physical activity is a cornerstone of health, wellness, and vitality, the impact of endurance exercise training on molecular signaling within and across tissues remains to be delineated. The Molecular Transducers of Physical Activity Consortium (MoTrPAC) was established to characterize molecular networks underlying the adaptive response to exercise. Here, we describe the endurance exercise training studies undertaken by the Preclinical Animal Sites Studies component of MoTrPAC, in which we sought to develop and implement a standardized endurance exercise protocol in a large cohort of rats. To this end, Adult (6-mo) and Aged (18-mo) female (n = 151) and male (n = 143) Fischer 344 rats were subjected to progressive treadmill training (5 d/wk, ∼70%-75% VO2max) for 1, 2, 4, or 8 wk; sedentary rats were studied as the control group. A total of 18 solid tissues, as well as blood, plasma, and feces, were collected to establish a publicly accessible biorepository and for extensive omics-based analyses by MoTrPAC. Treadmill training was highly effective, with robust improvements in skeletal muscle citrate synthase activity in as little as 1-2 wk and improvements in maximum run speed and maximal oxygen uptake by 4-8 wk. For body mass and composition, notable age- and sex-dependent responses were observed. This work in mature, treadmill-trained rats represents the most comprehensive and publicly accessible tissue biorepository, to date, and provides an unprecedented resource for studying temporal-, sex-, and age-specific responses to endurance exercise training in a preclinical rat model.


Assuntos
Adaptação Fisiológica , Envelhecimento , Condicionamento Físico Animal , Ratos Endogâmicos F344 , Animais , Masculino , Feminino , Condicionamento Físico Animal/fisiologia , Adaptação Fisiológica/fisiologia , Ratos , Envelhecimento/fisiologia , Resistência Física/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Treino Aeróbico
19.
Int J Med Sci ; 21(9): 1689-1700, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006847

RESUMO

Introduction: There is evidence that aging and obesity are associated with increased oxidative stress and chronic inflammation. High-intensity interval training (HIIT) may be superior to moderate-intensity continuous training (MICT) in anti-inflammatory and anti-obesity benefits. Therefore, the objective of this study is to determine which HIIT prescriptions will be more effective in reducing fat accumulation, inflammation, and improving metabolic adaptation and exercise performance in middle-aged and older overweight adults. Methods: Thirty-six middle-aged with overweight adults were divided into one of three groups: 1. L-HIIT group: the long-interval HIIT group (4 × 4 min Exercise/4 min Rest), 2. M-HIIT group: the medium-interval HIIT group (8 × 2 min Exercise/2 min Rest), 3. Control group: no exercise training intervention. All groups underwent the training stage for eight weeks (three sessions per week), followed by a detraining stage of four weeks in order to investigate the effects induced by different HIIT interventions on inflammation, metabolic adaptation, anti-fatigue and exercise performance, and fat loss Results: There was a significant physiological response in the change rate of heart rate (HR) after an acute L-HIIT session compared with an acute M-HIIT session (ΔHR: ↑49.66±16.09% vs ↑33.22±14.37%, p=0.02); furthermore, systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased significantly following a single L-HIIT session. After an eight-week training stage, the L-HIIT and M-HIIT groups exhibited a significant increase in aerobic capacity (ΔVO2peak), with values of +27.93±16.79% (p<0.001) and +18.39±8.12% (p<0.001), respectively, in comparison to the control group. Furthermore, in the L-HIIT group, the anaerobic power of relative mean power (RMP) exhibited a significant increase (p=0.019). However, following a four-week detraining stage, the adiponectin concentration remained 1.78 times higher in the L-HIIT group than in the control group (p=0.033). The results of blood sugar, blood lipids, body composition, and inflammatory markers did not indicate any improved it did not indicate any improvements from the two different HIIT protocols. Conclusions: The results indicate that an eight-week L-HIIT or M-HIIT intervention (three sessions per week, 32 minutes per session) may be an effective approach for improving aerobic capacity. It can be posited that L-HIIT may be a more advantageous mode than M-HIIT for enhancing anaerobic power, adipokine levels, and improving blood pressure in an aged and overweight population due to the induced physiological responses.


Assuntos
Adaptação Fisiológica , Treinamento Intervalado de Alta Intensidade , Sobrepeso , Humanos , Treinamento Intervalado de Alta Intensidade/métodos , Pessoa de Meia-Idade , Masculino , Feminino , Sobrepeso/terapia , Sobrepeso/fisiopatologia , Sobrepeso/metabolismo , Idoso , Frequência Cardíaca/fisiologia , Exercício Físico/fisiologia , Inflamação
20.
Proc Natl Acad Sci U S A ; 121(30): e2402559121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012831

RESUMO

Microbes face many physical, chemical, and biological insults from their environments. In response, cells adapt, but whether they do so cooperatively is poorly understood. Here, we use a model social bacterium, Myxococcus xanthus, to ask whether adapted traits are transferable to naïve kin. To do so we isolated cells adapted to detergent stresses and tested for trait transfer. In some cases, strain-mixing experiments increased sibling fitness by transferring adaptation traits. This cooperative behavior depended on a kin recognition system called outer membrane exchange (OME) because mutants defective in OME could not transfer adaptation traits. Strikingly, in mixed stressed populations, the transferred trait also benefited the adapted (actor) cells. This apparently occurred by alleviating a detergent-induced stress response in kin that otherwise killed actor cells. Additionally, this adaptation trait when transferred also conferred resistance against a lipoprotein toxin delivered to targeted kin. Based on these and other findings, we propose a model for stress adaptation and how OME in myxobacteria promotes cellular cooperation in response to environmental stresses.


Assuntos
Adaptação Fisiológica , Myxococcus xanthus , Myxococcus xanthus/fisiologia , Myxococcus xanthus/metabolismo , Estresse Fisiológico , Interações Microbianas/fisiologia
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