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1.
J Orthop Translat ; 48: 39-52, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39087139

RESUMO

Background: Osteocytes are the main stress-sensing cells in bone. The substances secreted by osteocytes under mechanical loading play a crucial role in maintaining body homeostasis. Osteocytes have recently been found to release exosomes into the circulation, but whether they are affected by mechanical loading or participate in the regulation of systemic homeostasis remains unclear. Methods: We used a tail-suspension model to achieve mechanical unloading on osteocytes. Osteocyte-specific CD63 reporter mice were used for osteocyte exosome tracing. Exosome detection and inhibitor treatment were performed to confirm the effect of mechanical loading on exosome secretion by osteocytes. Co-culture, GW4869 and exosome treatment were used to investigate the biological functions of osteocyte-derived exosomes on brown adipose tissue (BAT) and primary brown adipocytes. Osteocyte-specific Dicer KO mice were used to screen for loading-sensitive miRNAs. Dual luciferase assay was performed to validate the selected target gene. Results: Firstly, we found the thermogenic activity was increased in BAT of mice subjected to tail suspension, which is due to the effect of unloaded bone on circulating exosomes. Further, we showed that the secretion of exosomes from osteocytes is regulated by mechanical loading, and osteocyte-derived exosomes can reach BAT and affect thermogenic activity. More importantly, we confirmed the effect of osteocyte exosomes on BAT both in vivo and in vitro. Finally, we discovered that let-7e-5p contained in exosomes is under regulation of mechanical loading and regulates thermogenic activity of BAT by targeting Ppargc1a. Conclusion: Exosomes derived from osteocytes are loading-sensitive, and play a vital role in regulation on BAT, suggesting that regulation of exosomes secretion can restore homeostasis. The translational potential of this article: This study provides a biological rationale for using osteocyte exosomes as potential agents to modulate BAT and even whole-body homeostasis. It also provides a new pathological basis and a new treatment approach for mechanical unloading conditions such as spaceflight.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39147897

RESUMO

Considering the growing use of permeable pavements, the prediction of runoff passing through this pavement model is of considerable importance. The prediction of rainfall-runoff relationships can be a challenge because of several factors including data uncertainty, non-linear relationships, and high temporal and spatial variability. To deal with these challenges, intelligent algorithms are often used to predict such complex phenomena. In this research, runoff control parameters were investigated in two types of permeable pavements (permeable interlocking concrete pavement (PICP) and high strength clogging resistant permeable pavement (CRP)) using support vector machine (SVM), support vector machine-bat (SVM-BA) and support vector machine-grasshopper (SVM-GOA). Variables used in the models included percentage of coverage by permeable pavement (A), rainfall intensity (I), slope (S), and pavement type coefficient (K) as input data, and runoff coefficient (C), time to runoff (Tr), and peak discharge (Qp) as output data. In this research, from the total of 108 data extracted from the experimental results, 86 data were used in the training period, and 22 data were used in the test period. The results of the test period show that the SVM-BA model has the best performance with values of MAE = 0.010 in predicting C, MAE = 1.330 min in predicting Tr, and MAE = 0.029 lit/min in predicting Qp. The SVM-GOA model is ranked second with values of MAE = 0.051 in predicting C, MAE = 3.285 min in predicting Tr, and MAE = 0.097 lit/min in predicting Qp. Also, the SVM model is ranked third with values of MAE = 0.063 in predicting C, MAE = 4.470 min in predicting Tr, and MAE = 0.121 lit/min in predicting Qp. In summary, the SVM-BA algorithm showed the best performance and the SVM algorithm showed the weakest performance in predicting runoff characteristics in permeable pavements.

4.
J Cell Physiol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138923

RESUMO

The physical characteristics of brown adipose tissue (BAT) are defined by the presence of multilocular lipid droplets (LDs) within the brown adipocytes and a high abundance of iron-containing mitochondria, which give it its characteristic color. Normal mitochondrial function is, in part, regulated by organelle-to-organelle contacts. For example, the contact sites that mediate mitochondria-LD interactions are thought to have various physiological roles, such as the synthesis and metabolism of lipids. Aging is associated with mitochondrial dysfunction, and previous studies show that there are changes in mitochondrial structure and the proteins that modulate organelle contact sites. However, how mitochondria-LD interactions change with aging has yet to be fully clarified. Therefore, we sought to define age-related changes in LD morphology and mitochondria-lipid interactions in BAT. We examined the three-dimensional morphology of mitochondria and LDs in young (3-month) and aged (2-year) murine BAT using serial block face-scanning electron microscopy and the Amira program for segmentation, analysis, and quantification. Our analyses showed reductions in LD volume, area, and perimeter in aged samples in comparison to young samples. Additionally, we observed changes in LD appearance and type in aged samples compared to young samples. Notably, we found differences in mitochondrial interactions with LDs, which could implicate that these contacts may be important for energetics in aging. Upon further investigation, we also found changes in mitochondrial and cristae structure for the mitochondria interacting with LDs. Overall, these data define the nature of LD morphology and organelle-organelle contacts during aging and provide insight into LD contact site changes that interconnect biogerontology with mitochondrial function, metabolism, and bioactivity in aged BAT.

5.
Front Endocrinol (Lausanne) ; 15: 1440070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145314

RESUMO

Previous studies indicate that CNS administration of oxytocin (OT) reduces body weight in high fat diet-induced obese (DIO) rodents by reducing food intake and increasing energy expenditure (EE). We recently demonstrated that hindbrain (fourth ventricular [4V]) administration of OT elicits weight loss and elevates interscapular brown adipose tissue temperature (TIBAT, a surrogate measure of increased EE) in DIO mice. What remains unclear is whether OT-elicited weight loss requires increased sympathetic nervous system (SNS) outflow to IBAT. We hypothesized that OT-induced stimulation of SNS outflow to IBAT contributes to its ability to activate BAT and elicit weight loss in DIO mice. To test this hypothesis, we determined the effect of disrupting SNS activation of IBAT on the ability of 4V OT administration to increase TIBAT and elicit weight loss in DIO mice. We first determined whether bilateral surgical SNS denervation to IBAT was successful as noted by ≥ 60% reduction in IBAT norepinephrine (NE) content in DIO mice. NE content was selectively reduced in IBAT at 1-, 6- and 7-weeks post-denervation by 95.9 ± 2.0, 77.4 ± 12.7 and 93.6 ± 4.6% (P<0.05), respectively and was unchanged in inguinal white adipose tissue, pancreas or liver. We subsequently measured the effects of acute 4V OT (1, 5 µg ≈ 0.99, 4.96 nmol) on TIBAT in DIO mice following sham or bilateral surgical SNS denervation to IBAT. We found that the high dose of 4V OT (5 µg ≈ 4.96 nmol) elevated TIBAT similarly in sham mice as in denervated mice. We subsequently measured the effects of chronic 4V OT (16 nmol/day over 29 days) or vehicle infusions on body weight, adiposity and food intake in DIO mice following sham or bilateral surgical denervation of IBAT. Chronic 4V OT reduced body weight by 5.7 ± 2.23% and 6.6 ± 1.4% in sham and denervated mice (P<0.05), respectively, and this effect was similar between groups (P=NS). OT produced corresponding reductions in whole body fat mass (P<0.05). Together, these findings support the hypothesis that sympathetic innervation of IBAT is not necessary for OT-elicited increases in BAT thermogenesis and reductions of body weight and adiposity in male DIO mice.


Assuntos
Tecido Adiposo Marrom , Adiposidade , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Obesidade , Ocitocina , Sistema Nervoso Simpático , Animais , Ocitocina/farmacologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/inervação , Masculino , Camundongos , Obesidade/metabolismo , Sistema Nervoso Simpático/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Adiposidade/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos , Camundongos Obesos , Metabolismo Energético/efeitos dos fármacos , Norepinefrina/metabolismo
6.
Proc Biol Sci ; 291(2026): 20241137, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981525

RESUMO

Torpor is widespread among bats presumably because most species are small, and torpor greatly reduces their high mass-specific resting energy expenditure, especially in the cold. Torpor has not been recorded in any bat species larger than 50 g, yet in theory could be beneficial even in the world's largest bats (flying-foxes; Pteropus spp.) that are exposed to adverse environmental conditions causing energy bottlenecks. We used temperature telemetry to measure body temperature in wild-living adult male grey-headed flying-foxes (P. poliocephalus; 799 g) during winter in southern Australia. We found that all individuals used torpor while day-roosting, with minimum body temperature reaching 27°C. Torpor was recorded following a period of cool, wet and windy weather, and on a day with the coldest maximum air temperature, suggesting it is an adaptation to reduce energy expenditure during periods of increased thermoregulatory costs and depleted body energy stores. A capacity for torpor among flying-foxes has implications for understanding their distribution, behavioural ecology and life history. Furthermore, our discovery increases the body mass of bats known to use torpor by more than tenfold and extends the documented use of this energy-saving strategy under wild conditions to all bat superfamilies, with implications for the evolutionary maintenance of torpor among bats and other mammals.


Assuntos
Quirópteros , Torpor , Animais , Quirópteros/fisiologia , Torpor/fisiologia , Masculino , Metabolismo Energético , Telemetria , Temperatura Corporal , Estações do Ano , Austrália do Sul
7.
PeerJ ; 12: e17651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993980

RESUMO

Background: Genomic resource development for non-model organisms is rapidly progressing, seeking to uncover molecular mechanisms and evolutionary adaptations enabling thriving in diverse environments. Limited genomic data for bat species hinder insights into their evolutionary processes, particularly within the diverse Myotis genus of the Vespertilionidae family. In Mexico, 15 Myotis species exist, with three-M. vivesi, M. findleyi, and M. planiceps-being endemic and of conservation concern. Methods: We obtained samples of Myotis vivesi, M. findleyi, and M. planiceps for genomic analysis. Each of three genomic DNA was extracted, sequenced, and assembled. The scaffolding was carried out utilizing the M. yumanensis genome via a genome-referenced approach within the ntJoin program. GapCloser was employed to fill gaps. Repeat elements were characterized, and gene prediction was done via ab initio and homology methods with MAKER pipeline. Functional annotation involved InterproScan, BLASTp, and KEGG. Non-coding RNAs were annotated with INFERNAL, and tRNAscan-SE. Orthologous genes were clustered using Orthofinder, and a phylogenomic tree was reconstructed using IQ-TREE. Results: We present genome assemblies of these endemic species using Illumina NovaSeq 6000, each exceeding 2.0 Gb, with over 90% representing single-copy genes according to BUSCO analyses. Transposable elements, including LINEs and SINEs, constitute over 30% of each genome. Helitrons, consistent with Vespertilionids, were identified. Values around 20,000 genes from each of the three assemblies were derived from gene annotation and their correlation with specific functions. Comparative analysis of orthologs among eight Myotis species revealed 20,820 groups, with 4,789 being single copy orthogroups. Non-coding RNA elements were annotated. Phylogenomic tree analysis supported evolutionary chiropterans' relationships. These resources contribute significantly to understanding gene evolution, diversification patterns, and aiding conservation efforts for these endangered bat species.


Assuntos
Quirópteros , Genoma , Genômica , Filogenia , Animais , México , Genoma/genética , Quirópteros/genética , Genômica/métodos
8.
Sci Rep ; 14(1): 15124, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956387

RESUMO

Power systems exhibit nonlinearity. causing dynamic instability and complex power oscillations. This research proposes an innovative strategy using the Novel Bat Algorithm (NBA) to achieve ideal Power System Stabilizers (PSSs) in a multimachine power system. The approach shifts electromechanical modes to specific areas in the s-plane. Enhancing the multi-machine power system and establishing stabilizer parameters for dynamic performance. The study examines the designed approach aptitude for standard lead-lag PSSs configurations. In order to elevate the global search problem and transfer some static operators for the optimum optimization process. the chaos mapping. also known as CNBA. is introduced into NBA. Four different forms of chaos maps are compared in experiments to resolve unconstrained mathematical issues in order to illustrate CNBA performance. In any other case. the challenge of designing PSS under a wide range of loading situations is transformed into an optimization challenge with the damping ratio of electromechanical modes with low damping as the target function. The optimal stabilizers' gains are gotten by employing the CNBA algorithm. Second plan. an effective technique is astutely established to delineate the PSS location and quantity using CNBA and another side using participation factor. To examine the efficacy of the proposed CNBA-based PSS on a large system; it is tested on the interconnected of New-England/New-York (16 generators and 68 buses) power grid. and verified by comparative study with NBA through eigenvalue analysis and nonlinear simulation to provide evidence the algorithmic competence of CNBA. The CNBA approach yields a minimum damping ratio of 37%. which is consistent with the its eigenvalue. In contrast, the NBA approach achieves a minimum damping ratio of 31%. The simulation results reveal the fine performance of the proposed CNBA-PSS in a convincing manner and its capacity to provide an excellent damping for inter-area and local oscillations under diverse operating cases compared to NBA-PSS then in the case of PSS location.

9.
Elife ; 132024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037770

RESUMO

Bats have unique characteristics compared to other mammals, including increased longevity and higher resistance to cancer and infectious disease. While previous studies have analyzed the metabolic requirements for flight, it is still unclear how bat metabolism supports these unique features, and no study has integrated metabolomics, transcriptomics, and proteomics to characterize bat metabolism. In this work, we performed a multi-omics data analysis using a computational model of metabolic fluxes to identify fundamental differences in central metabolism between primary lung fibroblast cell lines from the black flying fox fruit bat (Pteropus alecto) and human. Bat cells showed higher expression levels of Complex I components of electron transport chain (ETC), but, remarkably, a lower rate of oxygen consumption. Computational modeling interpreted these results as indicating that Complex II activity may be low or reversed, similar to an ischemic state. An ischemic-like state of bats was also supported by decreased levels of central metabolites and increased ratios of succinate to fumarate in bat cells. Ischemic states tend to produce reactive oxygen species (ROS), which would be incompatible with the longevity of bats. However, bat cells had higher antioxidant reservoirs (higher total glutathione and higher ratio of NADPH to NADP) despite higher mitochondrial ROS levels. In addition, bat cells were more resistant to glucose deprivation and had increased resistance to ferroptosis, one of the characteristics of which is oxidative stress. Thus, our studies revealed distinct differences in the ETC regulation and metabolic stress responses between human and bat cells.


Assuntos
Quirópteros , Fibroblastos , Quirópteros/metabolismo , Humanos , Fibroblastos/metabolismo , Animais , Metabolômica , Espécies Reativas de Oxigênio/metabolismo , Proteômica/métodos , Linhagem Celular , Consumo de Oxigênio , Multiômica
10.
Wellcome Open Res ; 9: 107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39022322

RESUMO

We present a genome assembly from an individual male Myotis daubentonii (Daubenton's bat; Chordata; Mammalia; Chiroptera; Vespertilionidae). The genome sequence is 2,127.8 megabases in span. Most of the assembly is scaffolded into 23 chromosomal pseudomolecules, including the X and Y sex chromosomes. The mitochondrial genome has also been assembled and is 17.34 kilobases in length.

11.
J Mammal ; 105(4): 823-837, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39081265

RESUMO

Although Mexico holds the southernmost hibernating bats in North America, information on winter behavior and hibernacula microclimate use of temperate Mexican bats is limited. We studied hibernating bats at high altitudes (>1,000 m a.s.l.) in northern and central Mexico during 5 consecutive winters. Our aims were to document and describe the hibernacula, winter behavior (such as abundance and roost pattern), and microclimates (estimated as adjacent substrate temperature) of cave-hibernating bats in Mexico. We found 78 hibernacula and 6,089 torpid bats of 10 vespertilionid species, increasing by over 50% the number of cave-hibernating bat species and quadrupling the number of hibernacula for Mexico. Hibernacula were at altitudes between 1,049 and 3,633 m a.s.l., located in 3 mountain ranges, mainly in oak and conifer forests. Myotis velifer was the most common species, followed by Corynorhinus townsendii and C. mexicanus. We recorded the adjacent substrate temperatures from 9 species totaling 1,106 torpid bats and found differences in microclimate use among the 3 most common species. In general, abundance of torpid bats in our region of study was similar to those in the western United States, with aggregations of tens to a few hundred individuals per cave, and was lower than in the eastern United States where a cave may hold thousands of individuals. Knowledge of bat hibernation is crucial for developing conservation and management strategies on current conditions while accommodating environmental changes and other threats such as emerging diseases.


Aunque México tiene los murciélagos hibernantes más sureños en Norteamérica, la información sobre el comportamiento invernal y el uso de microclimas en los refugios de hibernación de los murciélagos templados mexicanos es limitada. Estudiamos a los murciélagos hibernantes en altitudes altas (>1000 msnm) en el norte y centro de México durante cinco inviernos consecutivos. Nuestros objetivos fueron documentar y describir las cuevas de hibernación, el comportamiento invernal (como la abundancia y patrón de percha), y el uso de microclimas (estimado como la temperatura del sustrato adyacente), de los murciélagos que hibernan en cuevas en México. Encontramos 78 cuevas de hibernación con 6089 murciélagos en torpor de 10 especies de vespertiliónidos, incrementando en más del 50% el número de especies de murciélagos que hibernan en cuevas y cuadriplicando el número de cuevas de hibernación para México. Las cuevas de hibernación estuvieron en elevaciones entre 1049 y 3633 msnm, localizadas en tres cadenas montañosas, principalmente en bosques de encinos y coníferas. Myotis velifer fue la especie más común, seguida por Corynorhinus townsendii y C. mexicanus. Reportamos las temperaturas del sustrato adyacente de 1106 murciélagos en torpor de nueve especies y encontramos diferencias en el uso de microclimas entre las tres especies más comunes. Aquí proveemos información relevante para especies de murciélagos templados en la ocurrencia más sureña de hibernación de murciélagos en Norteamérica. En general, la abundancia de murciélagos en torpor que encontramos fue similar a las del oeste de Estados Unidos, con agregaciones de decenas y algunos cientos de individuos por cueva; y fue menor que las del este de Estados Unidos, donde las cuevas pueden albergar miles de murciélagos. El conocimiento de la hibernación de murciélagos es crucial para el desarrollo de estrategias de conservación y manejo adecuadas en la actualidad y mientras se adaptan a los cambios ambientales y a otras amenazas tales como las enfermedades emergentes.

12.
Parasitol Res ; 123(7): 269, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995426

RESUMO

Nycteribiidae encompasses a specialized group of wingless blood-sucking flies that parasitize bats worldwide. Such relationships are frequently species- or genus-specific, indicating unique eco-evolutionary processes. However, despite this significance, comprehensive studies on the relationships of these flies with their hosts, particularly in the New World, have been scarce. Here, we provide a detailed description of the parasitological patterns of nycteribiid flies infesting a population of Myotis lavali bats in the Atlantic Forest of northeastern Brazil, considering the potential influence of biotic and abiotic factors on the establishment of nycteribiids on bat hosts. From July 2014 to June 2015, we captured 165 M. lavali bats and collected 390 Basilia travassosi flies. Notably, B. travassosi displayed a high prevalence and was the exclusive fly species parasitizing M. lavali in the surveyed area. Moreover, there was a significant predominance of female flies, indicating a female-biased pattern. The distribution pattern of the flies was aggregated; most hosts exhibited minimal or no parasitism, while a minority displayed heavy infestation. Sexually active male bats exhibited greater susceptibility to parasitism compared to their inactive counterparts, possibly due to behavioral changes during the peak reproductive period. We observed a greater prevalence and abundance of flies during the rainy season, coinciding with the peak reproductive phase of the host species. No obvious correlation was observed between the parasite load and bat body mass. Our findings shed light on the intricate dynamics of nycteribiid-bat interactions and emphasize the importance of considering various factors when exploring bat-parasite associations.


Assuntos
Quirópteros , Dípteros , Interações Hospedeiro-Parasita , Animais , Quirópteros/parasitologia , Dípteros/fisiologia , Brasil , Masculino , Feminino , Prevalência , Estações do Ano
13.
J Wildl Dis ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39053909

RESUMO

It has been proposed that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that spread through human populations as a pandemic originated in Asian bats. There is concern that infected humans could transmit the virus to native North American bats; therefore, the susceptibility of several North American bat species to the pandemic virus has been experimentally assessed. Big brown bats (Eptesicus fuscus) were shown to be resistant to infection by SARS-CoV-2, whereas Mexican free-tailed bats (Tadarida brasiliensis) became infected and orally excreted moderate amounts of virus for up to 18 d postinoculation. Little brown bats (Myotis lucifugus) frequently contact humans, and their populations are threatened over much of their range due to white-nose syndrome, a fungal disease that is continuing to spread across North America. We experimentally challenged little brown bats with SARS-CoV-2 to determine their susceptibility and host potential and whether the virus presents an additional risk to this species. We found that this species was resistant to infection by SARS-CoV-2. These findings provide reassurance to wildlife rehabilitators, biologists, conservation scientists, and the public at large who are concerned with possible transmission of this virus to threatened bat populations.

14.
Trop Med Infect Dis ; 9(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39058193

RESUMO

Lyssaviruses are neurotropic viruses capable of inducing fatal encephalitis. While rabies virus has been successfully eradicated in Belgium, the prevalence of other lyssaviruses remains uncertain. In this study, we conducted a survey on live animals and passive surveillance to investigate the presence of lyssaviruses in Belgium. In 2018, a total of 113 saliva samples and 87 blood samples were collected from bats. Saliva was subjected to RT-qPCR to identify lyssavirus infections. Additionally, an adapted lyssavirus neutralisation assay was set up for the detection of antibodies neutralising EBLV-1 in blood samples. Furthermore, we examined 124 brain tissue samples obtained from deceased bats during passive surveillance between 2016 and 2018. All saliva samples tested negative for lyssaviruses. Analysis of the blood samples uncovered the presence of lyssavirus-neutralising antibodies in five bat species and 32% of samples with a wide range depending on bat species, suggesting past exposure to a lyssavirus. Notably, EBLV-1 was detected in brain tissue samples from two Eptesicus serotinus specimens collected in 2016 near Bertrix and 2017 near Étalle, confirming for the first time the presence of EBLV-1 in Belgium and raising awareness of the potential risks associated with this species of bats as reservoirs of the virus.

15.
Horm Behav ; 164: 105606, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39059233

RESUMO

Several polygynous mammals exhibit reproductive skew in which only a few males reproduce. Successful males need strength, stamina and fighting ability to exclude competitors. Consequently, during the mating season their androgens and glucocorticoids are expected to increase to support spermatogenesis and aggressive behavior. But, during the nonmating season these hormones should decline to minimize deleterious effects, such as reduced immune function. Bats that exhibit harem polygyny in which males aggressively defend large groups of females year-round are ideal for assessing hormonal and other consequences of extreme polygyny. Here we use DNA methylation to estimate age and gas chromatography, tandem mass spectrometry to profile steroid metabolites in urine of wild greater spear-nosed bats, Phyllostomus hastatus, across seasons. We find that condition, measured by relative weight, is lower during the mating season for both sexes, although it remains high in harem males during the mating season. Average age of females is greater than males, and females exhibit substantial seasonal differences in androgens, estrogens and glucocorticoids with higher levels of all hormones during the mating season. Males, however, show little seasonal differences but substantial age-associated increases in most steroid metabolites. Harem males have larger, persistently scrotal testes and are older than bachelor males. While cortisone generally declines with age, harem males maintain higher amounts of biologically active cortisol than bachelor males all year and cortisol levels increase more quickly in response to restraint in males than in females. Taken together, these results suggest that attaining reproductive dominance requires hormone levels that reduce lifespan.

16.
Wellcome Open Res ; 9: 246, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39045151

RESUMO

We present a genome assembly from a female Plecotus auritus (Brown Long-eared bat; Chordata; Mammalia; Chiroptera; Vespertilionidae). The genome sequence is 2163.2 megabases in span. Most of the assembly is scaffolded into 16 chromosomal pseudomolecules, including the X sex chromosome. The mitochondrial genome has also been assembled and is 16.91 kilobases in length.

17.
Viruses ; 16(7)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39066178

RESUMO

Hepatitis B virus (HBV) infection leads to around 800,000 deaths yearly and is considered to be a major public health problem worldwide. However, HBV origins remain poorly understood. Here, we looked for bat HBV (BtHBV) in different bat species in Gabon to investigate the role of these animals as carriers of ancestral hepadnaviruses because these viruses are much more diverse in bats than in other host species. DNA was extracted from 859 bat livers belonging to 11 species collected in caves and villages in the southeast of Gabon and analyzed using PCRs targeting the surface gene. Positive samples were sequenced using the Sanger method. BtHBV DNA was detected in 64 (7.4%) individuals belonging to eight species mainly collected in caves. Thirty-six (36) sequences among the 37 obtained after sequencing were phylogenetically close to the RBHBV strain recently isolated in Gabonese bats, while the remaining sequence was close to a rodent HBV strain isolated in America. The generalized linear mixed model showed that the variable species best explained the occurrence of BtHBV infection in bats. The discovery of a BtHBV strain homologous to a rodent strain in bats raises the possibility that these animals may be carriers of ancestral hepadnaviruses.


Assuntos
Quirópteros , Variação Genética , Vírus da Hepatite B , Hepatite B , Filogenia , Quirópteros/virologia , Animais , Gabão/epidemiologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Prevalência , Hepatite B/virologia , Hepatite B/epidemiologia , Hepatite B/veterinária , DNA Viral/genética , Análise de Sequência de DNA
18.
Viruses ; 16(7)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39066279

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of COVID-19 and responsible for the global coronavirus pandemic which started in 2019. Despite exhaustive efforts to trace its origins, including potential links with pangolins and bats, the precise origins of the virus remain unclear. Bats have been recognized as natural hosts for various coronaviruses, including the Middle East respiratory coronavirus (MERS-CoV) and the SARS-CoV. This study presents a comparative analysis of the SARS-CoV-2 nucleocapsid protein (N) interactome in human and bat cell lines. We identified approximately 168 cellular proteins as interacting partners of SARS-CoV-2 N in human cells and 196 cellular proteins as interacting partners with this protein in bat cells. The results highlight pathways and events that are both common and unique to either bat or human cells. Understanding these interactions is crucial to comprehend the reasons behind the remarkable resilience of bats to viral infections. This study provides a foundation for a deeper understanding of host-virus interactions in different reservoirs.


Assuntos
COVID-19 , Quirópteros , Proteínas do Nucleocapsídeo de Coronavírus , Fosfoproteínas , Proteômica , SARS-CoV-2 , Quirópteros/virologia , Humanos , SARS-CoV-2/metabolismo , Animais , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Linhagem Celular , Proteômica/métodos , Fosfoproteínas/metabolismo , COVID-19/virologia , COVID-19/metabolismo , Interações Hospedeiro-Patógeno , Mapas de Interação de Proteínas
19.
Int J Mol Sci ; 25(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063092

RESUMO

Obesity, a global pandemic, poses a major threat to healthcare systems worldwide. Adipose tissue, the energy-storing organ during excessive energy intake, functions as a thermoregulator, interacting with other tissues to regulate systemic metabolism. Specifically, brown adipose tissue (BAT) is positively associated with an increased resistance to obesity, due to its thermogenic function in the presence of uncoupled protein 1 (UCP1). Recently, studies on climate change and the influence of environmental pollutants on energy homeostasis and obesity have drawn increasing attention. The reciprocal relationship between increasing adiposity and increasing temperatures results in reduced adaptive thermogenesis, decreased physical activity, and increased carbon footprint production. In addition, the impact of climate change makes obese individuals more prone to developing type 2 diabetes mellitus (T2DM). An impaired response to heat stress, compromised vasodilation, and sweating increase the risk of diabetes-related comorbidities. This comprehensive review provides information about the effects of climate change on obesity and adipose tissue, the risk of T2DM development, and insights into the environmental pollutants causing adipose tissue dysfunction and obesity. The effects of altered dietary patterns on adiposity and adaptation strategies to mitigate the detrimental effects of climate change are also discussed.


Assuntos
Tecido Adiposo , Poluição do Ar , Mudança Climática , Diabetes Mellitus Tipo 2 , Obesidade , Humanos , Poluição do Ar/efeitos adversos , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Obesidade/metabolismo , Obesidade/etiologia , Obesidade/epidemiologia , Animais , Tecido Adiposo/metabolismo , Termogênese , Tecido Adiposo Marrom/metabolismo , Metabolismo Energético , Adiposidade
20.
Environ Health Insights ; 18: 11786302241266051, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39071234

RESUMO

This research intricately explores the dynamics surrounding the coexistence of humans and roosting bats in urban areas, meticulously examining both the advantageous and detrimental aspects of their living arrangement. The study conducted a comprehensive survey with 286 residents in Iwo and Ogbomoso, where Eidolon helvum bats are known to roost, generating a robust dataset for thorough analysis. Rigorous statistical assessments, including the KMO and Bartlett's tests, confirmed the data's reliability at a significance level of P < .05. The respondent demographic revealed a predominance of 65% male participants, with an overwhelming 85% claiming familiarity with bats in their respective domains. Utilizing factor analysis, the study identified 8 salient variables from the initial 26, shedding light on diverse perceptions regarding bats: (i) Urban roosting (16.729%); (ii) Impact on tree growth (12.607%); (iii) Failed dislodgement attempts (11.504%); (iv) Medicinal value (10.240%); (v) Co-habitation preference (9.963%); (vi) Costly dislodgment consequences (9.963%); (vii) Beautification disruption (5.615%); and (viii) Structure defacement (5.510%). These factors were systematically categorized into 4 distinct themes: (A) Forced cohabitation (26.762%); (B) Environmental degradation by bats (23.732%); (C) Consequences of dislodging bats (21.477%); and (D) Acknowledged benefits of bats (10.240%). Co-habitation with bats becomes a necessity for ecological balance and, importantly, to safeguard the livelihood of roosting bats within their natural ecology, which man has encroached upon through urbanization, making all negatives arising from such existence self-inflicted by man. However, this study underscores the importance of human-bat cohabitation for mutual benefits, emphasizing potential detrimental consequences, including significant costs, associated with displacing bats from their natural ecosystem. These consequences may exacerbate the impacts of climate change, environmental degradation, and ecological imbalance. Further research is recommended to explore the positive aspects of the sustainable roosting bats' existence in the natural environment.

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