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1.
Food Res Int ; 186: 114379, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729702

RESUMEN

The relationship between the chemical composition and quality of Lushan Yunwu tea (LYT) from different geographical origins is not clear. Sensory evaluation, metabolomics analyses combined with chemometrics were conducted on LYT from 8 different geographical origins, and altitude was identified as the main factor responsible for the differences among LYT. A total of 32 non-volatile and 27 volatile compounds were identified as marker metabolites to distinguish the origins of high altitudes from those of low altitudes. LYT samples from higher altitude areas contained more free amino acids, sugars, and organic acids, and less catechins, which may contribute to the reduction of bitterness and astringency and the enhancement of umami. The contents of geranylacetone, ethyl hexanoate, ethyl caprylate, 3-carene, d-cadinene, linalool, nerol, and nerolidol in high altitude areas were higher than those in low altitude areas, indicating that LYT from high altitude had strong floral and fruity aroma. The altitudes were positively correlated with pH value, total flavonoids, soluble protein, total free amino acids, and the antioxidant capacities of the LYT. This study provided a theoretical basis for the study of the effect of altitude on tea quality.


Asunto(s)
Altitud , Metabolómica , , Compuestos Orgánicos Volátiles , Té/química , Compuestos Orgánicos Volátiles/análisis , Humanos , Odorantes/análisis , Gusto , Antioxidantes/análisis , Camellia sinensis/química , Aminoácidos/análisis , Flavonoides/análisis , Masculino , China , Femenino
2.
Food Res Int ; 187: 114392, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763654

RESUMEN

Variations in cultivars and cultivation altitudes have significant impacts on tea flavour compounds however lack of comprehensive understanding. This study provided insights into differential accumulation of crucial flavour compounds in response to cultivars, cultivation altitudes, and processing. Twelve flavonoids (262.4 âˆ¼ 275.4 mg•g-1) and 20 amino acids (AAs) (56.5 âˆ¼ 64.8 mg•g-1) were comparative analyzed in 'Longjing 43' and 'Qunti' fresh leaves harvested at low (80 m, LA) and high (500 m, HA) altitudes. Additionally, an in-depth correlation unravelling of 31 alkaloids, 25 fatty acids, 31 saccharides, 8 organic acids, and 7 vitamins and flavonoids/AAs during green tea (GT) and black tea (BT) processing was performed. Enhenced flavonoid accumulation alongside higher AAs and saccharides in HA GT promoted a sweet/mellow flavour. Abundant flavonoids, AAs, and saccharides derivates in LA BT gave rise to a sweet aftertaste. The study presents an integrated illustration of major flavour compounds' differential accumulation patterns and their interrelations, providing new insights into the influence of cultivation conditions on tea flavour.


Asunto(s)
Altitud , Camellia sinensis , Flavonoides , Hojas de la Planta , , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Flavonoides/análisis , Té/química , Camellia sinensis/química , Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/metabolismo , Gusto , Aminoácidos/análisis , Aminoácidos/metabolismo , Manipulación de Alimentos/métodos , Aromatizantes/análisis , Alcaloides/análisis , Alcaloides/metabolismo
3.
Nat Commun ; 15(1): 3970, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730227

RESUMEN

High-altitude hypoxia acclimatization requires whole-body physiological regulation in highland immigrants, but the underlying genetic mechanism has not been clarified. Here we use sheep as an animal model for low-to-high altitude translocation. We generate multi-omics data including whole-genome sequences, time-resolved bulk RNA-Seq, ATAC-Seq and single-cell RNA-Seq from multiple tissues as well as phenotypic data from 20 bio-indicators. We characterize transcriptional changes of all genes in each tissue, and examine multi-tissue temporal dynamics and transcriptional interactions among genes. Particularly, we identify critical functional genes regulating the short response to hypoxia in each tissue (e.g., PARG in the cerebellum and HMOX1 in the colon). We further identify TAD-constrained cis-regulatory elements, which suppress the transcriptional activity of most genes under hypoxia. Phenotypic and transcriptional evidence indicate that antenatal hypoxia could improve hypoxia tolerance in offspring. Furthermore, we provide time-series expression data of candidate genes associated with human mountain sickness (e.g., BMPR2) and high-altitude adaptation (e.g., HIF1A). Our study provides valuable resources and insights for future hypoxia-related studies in mammals.


Asunto(s)
Mal de Altura , Altitud , Regulación de la Expresión Génica , Hipoxia , Animales , Mal de Altura/genética , Mal de Altura/metabolismo , Ovinos , Hipoxia/genética , Hipoxia/metabolismo , Humanos , Aclimatación/genética , Transcripción Genética , Análisis de la Célula Individual , Femenino , Multiómica
4.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38731803

RESUMEN

This study explores the effects of normobaric hypoxia and intermittent hypoxic training (IHT) on the physiological condition of the cardiac muscle in swimmers. Hypoxia has been reported to elicit both beneficial and adverse changes in the cardiovascular system, but its impact on the myocardium during acute exercise and altitude/hypoxic training remains less understood. We aimed to determine how a single bout of intense interval exercise and a four-week period of high-intensity endurance training under normobaric hypoxia affect cardiac marker activity in swimmers. Sixteen young male swimmers were divided into two groups: one undergoing training in hypoxia and the other in normoxia. Cardiac markers, including troponin I and T (cTnI and cTnT), heart-type fatty acid-binding protein (H-FABP), creatine kinase-MB isoenzyme (CK-MB), and myoglobin (Mb), were analyzed to assess the myocardium's response. We found no significant differences in the physiological response of the cardiac muscle to intense physical exertion between hypoxia and normoxia. Four weeks of IHT did not alter the resting levels of cTnT, cTnI, and H-FABP, but it resulted in a noteworthy decrease in the resting concentration of CK-MB, suggesting enhanced cardiac muscle adaptation to exercise. In contrast, a reduction in resting Mb levels was observed in the control group training in normoxia. These findings suggest that IHT at moderate altitudes does not adversely affect cardiac muscle condition and may support cardiac muscle adaptation, affirming the safety and efficacy of IHT as a training method for athletes.


Asunto(s)
Atletas , Biomarcadores , Hipoxia , Humanos , Masculino , Hipoxia/metabolismo , Proyectos Piloto , Natación/fisiología , Adulto Joven , Miocardio/metabolismo , Mioglobina/metabolismo , Troponina I/metabolismo , Proteína 3 de Unión a Ácidos Grasos/metabolismo , Adolescente , Proteínas de Unión a Ácidos Grasos/metabolismo , Resistencia Física/fisiología , Forma MB de la Creatina-Quinasa/sangre , Forma MB de la Creatina-Quinasa/metabolismo , Adaptación Fisiológica , Altitud
5.
BMJ Open ; 14(5): e078018, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692719

RESUMEN

OBJECTIVE: To investigate the differences in myopia prevalence and ocular biometry in children and adolescents in Chongqing and Tibet, China. DESIGN: Cross-sectional study. SETTING: The study included children and adolescents aged 6-18 years in Chongqing, a low-altitude region, and in Qamdo, a high-altitude region of Tibet. PARTICIPANTS: A total of 448 participants in Qamdo, Tibet, and 748 participants in Chongqing were enrolled in this study. METHODS: All participants underwent uncorrected visual acuity assessment, non-cycloplegic refraction, axial length (AL) measurement, intraocular pressure (IOP) measurement and corneal tomography. And the participants were grouped according to age (6-8, 9-11, 12-14 and 15-18 years group), and altitude of location (primary school students: group A (average altitude: 325 m), group B (average altitude: 2300 m), group C (average altitude: 3250 and 3170 m) and group D (average altitude: 3870 m)). RESULTS: There was no statistical difference in mean age (12.09±3.15 vs 12.2±3.10, p=0.549) and sex distribution (males, 50.4% vs 47.6%, p=0.339) between the two groups. The Tibet group presented greater spherical equivalent (SE, -0.63 (-2.00, 0.13) vs -0.88 (-2.88, -0.13), p<0.001), shorter AL (23.45±1.02 vs 23.92±1.19, p<0.001), lower prevalence of myopia (39.7% vs 47.6%, p=0.008) and flatter mean curvature power of the cornea (Km, 43.06±1.4 vs 43.26±1.36, p=0.014) than the Chongqing group. Further analysis based on age subgroups revealed that the Tibet group had a lower prevalence of myopia and higher SE in the 12-14, and 15-18 years old groups, shorter AL in the 9-11, 12-14 and 15-18 years old groups, and lower AL to corneal radius of curvature ratio (AL/CR) in all age subgroups compared with the Chongqing group, while Km was similar between the two groups in each age subgroup. Simple linear regression analysis showed that SE decreased with age in both the Tibet and Chongqing groups, with the Tibet group exhibiting a slower rate of decrease (p<0.001). AL and AL/CR increased with age in both the Tibet and Chongqing groups, but the rate of increase was slower in the Tibet group (p<0.001 of both). Multiple linear regression analysis revealed that AL had the greatest effect on SE in both groups, followed by Km. In addition, the children and adolescents in Tibet presented thinner corneal thickness (CCT, p<0.001), smaller white to white distance (WTW, p<0.001), lower IOP (p<0.001) and deeper anterior chamber depth (ACD, p=0.015) than in Chongqing. Comparison of altitude subgroups showed that the prevalence of myopia (p=0.002), SE (p=0.031), AL (p=0.001) and AL/CR (p<0.001) of children at different altitudes was statistically different but the Km (p=0.189) were similar. The highest altitude, Tengchen County, exhibited the lowest prevalence of myopia and greatest SE among children, and the mean AL also decreased with increasing altitude. CONCLUSIONS: Myopia prevalence in Tibet was comparable with that in Chongqing for students aged 6-8 and 9-11 years but was lower and myopia progressed more slowly for students aged 12-14 and 15-18 years than in Chongqing, and AL was the main contributor for this difference, which may be related to higher ultraviolet radiation exposure and lower IOP in children and adolescents at high altitude in Tibet. Differences in AL and AL/CR between Tibet and Chongqing children and adolescents manifested earlier than in SE, underscoring the importance of AL measurement in myopia screening.


Asunto(s)
Altitud , Biometría , Miopía , Refracción Ocular , Humanos , Adolescente , Niño , Estudios Transversales , Masculino , Femenino , Tibet/epidemiología , Miopía/epidemiología , Prevalencia , China/epidemiología , Refracción Ocular/fisiología , Agudeza Visual , Longitud Axial del Ojo/diagnóstico por imagen , Presión Intraocular/fisiología , Córnea/diagnóstico por imagen , Córnea/patología , Córnea/anatomía & histología
6.
Gut Microbes ; 16(1): 2350151, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715346

RESUMEN

The extreme environmental conditions of a plateau seriously threaten human health. The relationship between gut microbiota and human health at high altitudes has been extensively investigated. However, no universal gut microbiota biomarkers have been identified in the plateau population, limiting research into gut microbiota and high-altitude adaptation. 668 16s rRNA samples were analyzed using meta-analysis to reduce batch effects and uncover microbiota biomarkers in the plateau population. Furthermore, the robustness of these biomarkers was validated. Mendelian randomization (MR) results indicated that Tibetan gut microbiota may mediate a reduced erythropoietic response. Functional analysis and qPCR revealed that butyrate may be a functional metabolite in high-altitude adaptation. A high-altitude rat model showed that butyrate reduced intestinal damage caused by high altitudes. According to cell experiments, butyrate may downregulate hypoxia-inducible factor-1α (HIF-1α) expression and blunt cellular responses to hypoxic stress. Our research found universally applicable biomarkers and investigated their potential roles in promoting human health at high altitudes.


Asunto(s)
Altitud , Biomarcadores , Butiratos , Microbioma Gastrointestinal , Subunidad alfa del Factor 1 Inducible por Hipoxia , Humanos , Tibet , Butiratos/metabolismo , Butiratos/análisis , Biomarcadores/análisis , Animales , Ratas , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , ARN Ribosómico 16S/genética , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Masculino , Adaptación Fisiológica , Análisis de la Aleatorización Mendeliana
7.
BMC Plant Biol ; 24(1): 371, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724940

RESUMEN

Variations in functional traits serve as measures of plants' ability to adapt to environment. Exploring the patterns of functional traits of desert plants along elevational gradients is helpful to understand the responses and adaptation strategies of species to changing environments. However, it is unknown whether the relationship between functional traits and elevation is affected by differences in the species' elevational distributions (elevation preference and species' range). Importantly, most researches have concerned with differences in mean trait values and ignored intraspecific trait variation. Here, we measured functional traits of desert plants along a wide elevational gradient in the Tibetan Plateau and adjacent areas and explored functional trait patterns over elevation in species with different elevational distributions. We decomposed trait variation and further investigated characterizations of intraspecific variation. Ultimately, the main drivers of trait variation were identified using redundancy analysis. We found that species' elevational distributions significantly influenced the relationship of functional traits such as plant height, leaf dry matter content, leaf thickness, leaf nitrogen and carbon content with elevation. Species with a lower elevational preference showed greater trait variation than species with a higher elevational preference, suggesting that species that prefer high elevation are more conservative facing environmental changes. We provide evidence that interspecific trait variation in leaf thickness and leaf carbon content decreased with increasing species' range, indicating that increased variations in resistance traits within species make greater responsiveness to environmental changes, enabling species a wider range. Elevation, temperature and precipitation were the main drivers of trait variation in species with a low elevational preference, while the effect of precipitation on trait variation in species with a high elevational preference was not significant. This study sheds new insights on how plants with different elevational distributions regulate their ecological strategies to cope with changing environments.


Asunto(s)
Altitud , Clima Desértico , Tibet , Hojas de la Planta/fisiología , Hojas de la Planta/anatomía & histología
8.
Sci Rep ; 14(1): 11585, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773195

RESUMEN

High-altitude cerebral edema (HACE) is a severe neurological condition that can occur at high altitudes. It is characterized by the accumulation of fluid in the brain, leading to a range of symptoms, including severe headache, confusion, loss of coordination, and even coma and death. Exosomes play a crucial role in intercellular communication, and their contents have been found to change in various diseases. This study analyzed the metabolomic characteristics of blood exosomes from HACE patients compared to those from healthy controls (HCs) with the aim of identifying specific metabolites or metabolic pathways associated with the development of HACE conditions. A total of 21 HACE patients and 21 healthy controls were recruited for this study. Comprehensive metabolomic profiling of the serum exosome samples was conducted using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC‒MS/MS). Additionally, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed to identify the metabolic pathways affected in HACE patients. Twenty-six metabolites, including ( +)-camphoric acid, choline, adenosine, adenosine 5'-monophosphate, deoxyguanosine 5'-monophosphate, guanosine, and hypoxanthine-9-ß-D-arabinofuranoside, among others, exhibited significant changes in expression in HACE patients compared to HCs. Additionally, these differentially abundant metabolites were confirmed to be potential biomarkers for HACE. KEGG pathway enrichment analysis revealed several pathways that significantly affect energy metabolism regulation (such as purine metabolism, thermogenesis, and nucleotide metabolism), estrogen-related pathways (the estrogen signaling pathway, GnRH signaling pathway, and GnRH pathway), cyclic nucleotide signaling pathways (the cGMP-PKG signaling pathway and cAMP signaling pathway), and hormone synthesis and secretion pathways (renin secretion, parathyroid hormone synthesis, secretion and action, and aldosterone synthesis and secretion). In patients with HACE, adenosine, guanosine, and hypoxanthine-9-ß-D-arabinofuranoside were negatively correlated with height. Deoxyguanosine 5'-monophosphate is negatively correlated with weight and BMI. Additionally, LPE (18:2/0:0) and pregnanetriol were positively correlated with age. This study identified potential biomarkers for HACE and provided valuable insights into the underlying metabolic mechanisms of this disease. These findings may lead to potential targets for early diagnosis and therapeutic intervention in HACE patients.


Asunto(s)
Biomarcadores , Edema Encefálico , Exosomas , Metabolómica , Humanos , Masculino , Femenino , Adulto , Metabolómica/métodos , Edema Encefálico/sangre , Edema Encefálico/metabolismo , Edema Encefálico/etiología , Biomarcadores/sangre , Exosomas/metabolismo , Espectrometría de Masas en Tándem , Mal de Altura/sangre , Mal de Altura/metabolismo , Persona de Mediana Edad , Redes y Vías Metabólicas , Metaboloma , Estudios de Casos y Controles , Altitud
9.
Sci Total Environ ; 932: 172829, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692332

RESUMEN

Permafrost serves as a natural cold reservoir for viral communities. However, little is known about the viromes in deep permafrost soil, as most studies of permafrost were restricted to shallow areas. Here, permafrost soil samples of up to 100 m in depth were collected from two sites in the Tuotuo River permafrost area on the Tibetan Plateau. We investigated the viral composition in these permafrost soil samples and analyzed the relationship of viral composition and diversity along with depths. Our study revealed that greater permafrost thickness corresponds to higher diversity within the viral community. Bacteriophages were found to be the dominant viral communities, with "kill the winner" dynamics observed within the Siphoviridae and Myoviridae. The abundance and diversity of viral communities may follow a potential pattern along soil layers and depths, influenced by pH, trace elements, and permafrost thickness. Notably, strong correlations were discovered between the content of inorganic elements, including B, Mg, Cr, Bi, Ti, Na, Ni, and Cu, and the viral composition. Moreover, we discovered highly conserved sequences of giant viruses at depth of 10, 20, and 50 m in permafrost, which play a crucial role in evolutionary processes. These findings provide valuable insights into the viral community patterns from shallow to 100-m-depth in high-elevation permafrost, offering crucial data support for the formulation of strategies for permafrost thaw caused by climate change and anthropogenic activities.


Asunto(s)
Hielos Perennes , Tibet , Microbiología del Suelo , Viroma , Altitud , Monitoreo del Ambiente , Suelo/química , Virus
10.
Sleep Med Clin ; 19(2): 327-337, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38692756

RESUMEN

In a variety of physiologic and pathologic states, people may experience both chronic sustained hypoxemia and intermittent hypoxemia ("combined" or "overlap" hypoxemia). In general, hypoxemia in such instances predicts a variety of maladaptive outcomes, including excess cardiovascular disease or mortality. However, hypoxemia may be one of the myriad phenotypic effects in such states, making it difficult to ascertain whether adverse outcomes are primarily driven by hypoxemia, and if so, whether these effects are due to intermittent versus sustained hypoxemia.


Asunto(s)
Altitud , Hipoxia , Síndromes de la Apnea del Sueño , Humanos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/terapia , Enfermedad Crónica , Enfermedades Pulmonares/complicaciones
11.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230116, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38705191

RESUMEN

Many insects depend on high-altitude, migratory movements during part of their life cycle. The daily timing of these migratory movements is not random, e.g. many insect species show peak migratory flight activity at dawn, noon or dusk. These insects provide essential ecosystem services such as pollination but also contribute to crop damage. Quantifying the diel timing of their migratory flight and its geographical and seasonal variation, are hence key towards effective conservation and pest management. Vertical-looking radars provide continuous and automated measurements of insect migration, but large-scale application has not been possible because of limited availability of suitable devices. Here, we quantify patterns in diel flight periodicity of migratory insects between 50 and 500 m above ground level during March-October 2021 using a network of 17 vertical-looking radars across Europe. Independent of the overall daily migratory movements and location, peak migratory movements occur around noon, during crepuscular evening and occasionally the morning. Relative daily proportions of insect migration intensity and traffic during the diel phases of crepuscular-morning, day, crepuscular-evening and night remain largely equal throughout May-September and across Europe. These findings highlight, extend, and generalize previous regional-scale findings on diel migratory insect movement patterns to the whole of temperate Europe. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Asunto(s)
Altitud , Migración Animal , Vuelo Animal , Insectos , Animales , Vuelo Animal/fisiología , Europa (Continente) , Insectos/fisiología , Estaciones del Año
12.
Reprod Domest Anim ; 59(5): e14582, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38715452

RESUMEN

Crossbred cattle are commonly used for milk production in the tropics, combining the potential benefits of pure breeds with the heterosis effects of the offspring. However, no comprehensive assessment of lifetime productivity for crossbred versus purebred cattle in low-altitude tropical environments has been carried out. The present study compares the lifetime productivity of purebred Holstein (HO, n = 17,269), Gyr (GY4, n = 435), and Brahman (BR4, n = 622) with crossbreds Gyr × Holstein (GY × HO, n = 5521) and Brahman×Holstein (BR × HO, n = 5429) cows from dairy farms located in low and medium altitude tropical regions in Costa Rica. The production traits of interest were age at first calving (AFC), days open (DO), milk production per lactation (TMP), lactation length (LLEN), age at culling (ACUL), and number of lactations (NLAC). Estimates of heterosis were also calculated. The AFC for GY × HO crosses (33-34 months) was not significantly different (p > .05) from HO (33.8 months). For BR × HO crosses, a significant (p < .05) decrease in AFC (BR3HO1 35.6 months, BR2HO2 34.5 months, and BR1H03 33.3 months) was observed as the fraction of HO breed increased. Estimates of heterosis for AFC were favourable for both crosses, of a magnitude close to 3%. The DO for F1 crosses (GY2HO2 94 days; BR2HO2 96 days) was significantly (p < .05) lower than HO (123 days). Estimates of heterosis for DO were also favourable and above 15% for both crosses. The TMP and LLEN were higher for HO (TMP = 5003 kg; LLEN = 324 days) compared with GY × HO (TMP = 4428 to 4773 kg; LLEN = 298 to 312 days) and BR × HO (TMP = 3950 to 4761 kg; LLEN = 273 to 313 days) crosses. Heterosis for TMP was favourable but low for both crosses, with a magnitude below 3.0%. The NLAC for HO (4.6 lactations) was significantly (p < .05) lower than F1 (GY2HO2, 5.8 lactations; BR2HO2, 5.4 lactations). Heterosis for NLAC was above 6.0% for both crosses. Overall, estimates of lifetime income over feed costs per cow on average were USD 2637 (30.3%) and USD 734 (8.4%) higher in F1 GY × HO and BR × HO, respectively, compared to HO. In conclusion, crossbred animals, specifically those with Gyr and Brahman genetics, extend the productive lifespan, increasing economic returns.


Asunto(s)
Vigor Híbrido , Lactancia , Leche , Clima Tropical , Animales , Bovinos/genética , Bovinos/fisiología , Lactancia/genética , Lactancia/fisiología , Femenino , Costa Rica , Cruzamiento , Hibridación Genética , Altitud , Cruzamientos Genéticos
13.
PeerJ ; 12: e17148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38708360

RESUMEN

One of the most vulnerable phases in the plant life cycle is sexual reproduction, which depends on effective pollen transfer, but also on the thermotolerance of pollen grains. Pollen thermotolerance is temperature-dependent and may be reduced by increasing temperature associated with global warming. A growing body of research has focused on the effect of increased temperature on pollen thermotolerance in crops to understand the possible impact of temperature extremes on yield. Yet, little is known about the effects of temperature on pollen thermotolerance of wild plant species. To fill this gap, we selected Lotus corniculatus s.l. (Fabaceae), a species common to many European habitats and conducted laboratory experiments to test its pollen thermotolerance in response to artificial increase in temperature. To test for possible local adaptation of pollen thermal tolerance, we compared data from six lowland (389-451 m a.s.l.) and six highland (841-1,030 m a.s.l.) populations. We observed pollen germination in vitro at 15 °C, 25 °C, 30 °C, and 40 °C. While lowland plants maintained a stable germination percentage across a broad temperature range (15-30 °C) and exhibited reduced germination only at extremely high temperatures (40 °C), highland plants experienced reduced germination even at 30 °C-temperatures commonly exceeded in lowlands during warm summers. This suggests that lowland populations of L. corniculatus may be locally adapted to higher temperature for pollen germination. On the other hand, pollen tube length decreased with increasing temperature in a similar way in lowland and highland plants. The overall average pollen germination percentage significantly differed between lowland and highland populations, with highland populations displaying higher germination percentage. On the other hand, the average pollen tube length was slightly smaller in highland populations. In conclusion, we found that pollen thermotolerance of L. corniculatus is reduced at high temperature and that the germination of pollen from plant populations growing at higher elevations is more sensitive to increased temperature, which suggests possible local adaptation of pollen thermotolerance.


Asunto(s)
Lotus , Polen , Termotolerancia , Polen/fisiología , Termotolerancia/fisiología , Lotus/fisiología , Lotus/crecimiento & desarrollo , Adaptación Fisiológica/fisiología , Calentamiento Global , Germinación/fisiología , Altitud , Cambio Climático , Temperatura , Aclimatación/fisiología
14.
Proc Natl Acad Sci U S A ; 121(21): e2313599121, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38739790

RESUMEN

The ecoevolutionary drivers of species niche expansion or contraction are critical for biodiversity but challenging to infer. Niche expansion may be promoted by local adaptation or constrained by physiological performance trade-offs. For birds, evolutionary shifts in migratory behavior permit the broadening of the climatic niche by expansion into varied, seasonal environments. Broader niches can be short-lived if diversifying selection and geography promote speciation and niche subdivision across climatic gradients. To illuminate niche breadth dynamics, we can ask how "outlier" species defy constraints. Of the 363 hummingbird species, the giant hummingbird (Patagona gigas) has the broadest climatic niche by a large margin. To test the roles of migratory behavior, performance trade-offs, and genetic structure in maintaining its exceptional niche breadth, we studied its movements, respiratory traits, and population genomics. Satellite and light-level geolocator tracks revealed an >8,300-km loop migration over the Central Andean Plateau. This migration included a 3-wk, ~4,100-m ascent punctuated by upward bursts and pauses, resembling the acclimatization routines of human mountain climbers, and accompanied by surging blood-hemoglobin concentrations. Extreme migration was accompanied by deep genomic divergence from high-elevation resident populations, with decisive postzygotic barriers to gene flow. The two forms occur side-by-side but differ almost imperceptibly in size, plumage, and respiratory traits. The high-elevation resident taxon is the world's largest hummingbird, a previously undiscovered species that we describe and name here. The giant hummingbirds demonstrate evolutionary limits on niche breadth: when the ancestral niche expanded due to evolution (or loss) of an extreme migratory behavior, speciation followed.


Asunto(s)
Migración Animal , Aves , Especiación Genética , Animales , Migración Animal/fisiología , Aves/genética , Aves/fisiología , Aves/clasificación , Ecosistema , Altitud , Evolución Biológica
15.
Sci Rep ; 14(1): 10206, 2024 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702334

RESUMEN

Cardiovascular function and adipose metabolism were markedly influenced under high altitudes. However, the interplay between adipokines and heart under hypoxia remains to be elucidated. We aim to explore alterations of adipokines and underlying mechanisms in regulating cardiac function under high altitudes. We investigated the cardiopulmonary function and five adipokines in Antarctic expeditioners at Kunlun Station (4,087 m) for 20 days and established rats exposed to hypobaric hypoxia (5,000 m), simulating Kunlun Station. Antarctic expeditioners exhibited elevated heart rate, blood pressure, systemic vascular resistance, and decreased cardiac pumping function. Plasma creatine phosphokinase-MB (CK-MB) and platelet-endothelial cell adhesion molecule-1 (sPecam-1) increased, and leptin, resistin, and lipocalin-2 decreased. Plasma leptin significantly correlated with altered cardiac function indicators. Additionally, hypoxic rats manifested impaired left ventricular systolic and diastolic function, elevated plasma CK-MB and sPecam-1, and decreased plasma leptin. Chronic hypoxia for 14 days led to increased myocyte hypertrophy, fibrosis, apoptosis, and mitochondrial dysfunction, coupled with reduced protein levels of leptin signaling pathways in myocardial tissues. Cardiac transcriptome analysis revealed leptin was associated with downregulated genes involved in rhythm, Na+/K+ transport, and cell skeleton. In conclusion, chronic hypoxia significantly reduced leptin signaling pathways in cardiac tissues along with significant pathological changes, thus highlighting the pivotal role of leptin in regulation of cardiac function under high altitudes.


Asunto(s)
Altitud , Hipoxia , Leptina , Transducción de Señal , Leptina/metabolismo , Leptina/sangre , Animales , Ratas , Masculino , Hipoxia/metabolismo , Hipoxia/fisiopatología , Humanos , Mal de Altura/metabolismo , Mal de Altura/fisiopatología , Miocardio/metabolismo , Miocardio/patología , Adulto , Corazón/fisiopatología
16.
J Ethnobiol Ethnomed ; 20(1): 54, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38764009

RESUMEN

BACKGROUND: In northwestern Pakistan, Lotkuh is a high-altitude terrain nestled within the eastern Hindu Kush region. Enclaved by towering peaks and harboring a unique culture, the region mirrors the geographical and cultural diversity of Pakistan. In this geographically isolated region, a treasure trove of ethnobotanical knowledge unfolds through generations of interaction between the inhabitants and indigenous plants, resulting in a profound understanding of the plant uses in nutritional, medicinal, cultural, and ritual contexts. Thus, the study seeks to gather, analyze, and document the indigenous knowledge of plant utilization of the distinct tribal culture. METHODS: Through semi-structured questionnaires, inventory interviews, and participatory workshops, data were collected by engaging a cohort of 120 local respondents. The collected data were then classified into nine distinct use categories, following which quantitative indices were calculated. RESULTS: The research identified a total of 150 plant species spanning across 59 different families and categorized them into 9 distinct usage groups. Among these, Astragalus oihorensis, Astragalus owirensis, Cicer nuristanicum, Geranium parmiricum, and Rochelia chitralensis stand out as novel species with distinctive applications. Notably, medicinal use garnered 600 reports, while animal feed, veterinary applications, human consumption, and toxicity recorded 500, 450, 425, and 104 reports, respectively. Informant consensus was high ranging between 0.8 and 0.9 with most agreement on human food and animal feed category. Platanus orientalis and Juglans regia, with RFC 0.91, were the most cited. The Family Importance Value (FIV) of Juglandaceae and Platanaceae, each with an FIV of 0.91, and Capparidaceae with an FIV of 0.83 indicate the intricate role the families play. CONCLUSIONS: In this study, we explore 150 ethnobotanical species, uncovering novel entries within ethnobotanical literature. Among these, several species showcase unique uses previously undocumented in Pakistani literature. Our research sheds light on the intricate interaction between plants and the distinct cultural landscape of the Lotkuh region.


Asunto(s)
Altitud , Etnobotánica , Plantas Medicinales , Pakistán , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Fitoterapia , Medicina Tradicional , Encuestas y Cuestionarios
17.
Sci Total Environ ; 931: 172930, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38701932

RESUMEN

Similarly to other European mountain areas, in Serra da Estrela the grazing pressure has been reducing due to social and economic drivers that have pushed shepherds and sheep to the foothill, or plainly out of the sector. Shrub encroachment on commons and other previously grazed land is one of the most tangible effects of pastoral abandonment in Serra de Estrela. The impacts of the resulting increase in landscape continuity and biomass availability were made clear in the severe fires of 2017 and 2022. As fire risk is likely to increase with climate change, it becomes urgent to understand what strategies can be deployed to keep fragmentation in these landscapes. Key actors such as shepherds should be involved in this discussion to understand their perceptions, points of view and reasons for abandoning upland pastures. In this study, we use fuzzy cognitive mapping to identify the key variables and mechanisms affecting the pastoral system according to local shepherds. In our study, we developed with local stakeholders a framework outlining the local pastoral system. Based on that, we carried out the fuzzy cognitive mapping collecting 14 questionnaires. We found that shepherds' income is a central issue, but that it is highly dependent on many factors. Increasing the Common Agricultural Policy payments alone is not enough to incentivise the use of upland pastures. More targeted strategies, such as more support for shrub clearing, and direct payments conditional to transhumance are more impactful. Despite a contentious discourse between conservation and shepherding values in Serra da Estrela, we find that shepherd's values are aligned with biodiversity conservation and a potential nature-based solution for minimizing fire risk through woody fuel management. This opens up possibilities for new governance strategies, that put Serra da Estrela's social, environmental and cultural values at its core.


Asunto(s)
Altitud , Conservación de los Recursos Naturales , Animales , España , Cambio Climático , Lógica Difusa , Agricultura , Pradera
18.
PeerJ ; 12: e17166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38563004

RESUMEN

Objectives: To test the hypothesis that 'live high-base train high-interval train low' (HiHiLo) altitude training, compared to 'live low-train high' (LoHi), yields greater benefits on performance and physiological adaptations. Methods: Sixteen young male middle-distance runners (age, 17.0 ± 1.5 y; body mass, 58.8 ± 4.9 kg; body height, 176.3 ± 4.3 cm; training years, 3-5 y; training distance per week, 30-60 km.wk-1) with a peak oxygen uptake averaging ~65 ml.min-1.kg-1 trained in a normobaric hypoxia chamber (simulated altitude of ~2,500 m, monitored by heart rate ~170 bpm; thrice weekly) for 3 weeks. During this period, the HiHiLo group (n = 8) stayed in normobaric hypoxia (at ~2,800 m; 10 h.day-1), while the LoHi group (n = 8) resided near sea level. Before and immediately after the intervention, peak oxygen uptake and exercise-induced arterial hypoxemia responses (incremental cycle test) as well as running performance and time-domain heart rate variability (5-km time trial) were assessed. Hematological variables were monitored at baseline and on days 1, 7, 14 and 21 during the intervention. Results: Peak oxygen uptake and running performance did not differ before and after the intervention in either group (all P > 0.05). Exercise-induced arterial hypoxemia responses, measured both at submaximal (240 W) and maximal loads during the incremental test, and log-transformed root mean square of successive R-R intervals during the 4-min post-run recovery period, did not change (all P > 0.05). Hematocrit, mean reticulocyte absolute count and reticulocyte percentage increased above baseline levels on day 21 of the intervention (all P < 0.001), irrespective of group. Conclusions: Well-trained runners undertaking base training at moderate simulated altitude for 3 weeks, with or without hypoxic residence, showed no performance improvement, also with unchanged time-domain heart rate variability and exercise-induced arterial hypoxemia responses.


Asunto(s)
Altitud , Tolerancia al Ejercicio , Masculino , Humanos , Adolescente , Consumo de Oxígeno/fisiología , Hipoxia , Adaptación Fisiológica , Oxígeno
19.
Glob Chang Biol ; 30(4): e17260, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38563236

RESUMEN

The impact of anthropogenic global warming has induced significant upward dispersal of trees to higher elevations at alpine treelines. Assessing vertical deviation from current uppermost tree distributions to potential treeline positions is crucial for understanding ecosystem responses to evolving global climate. However, due to data resolution constraints and research scale limitation, comprehending the global pattern of alpine treeline elevations and driving factors remains challenging. This study constructed a comprehensive quasi-observational dataset of uppermost tree distribution across global mountains using Google Earth imagery. Validating the isotherm of mean growing-season air temperature at 6.6 ± 0.3°C as the global indicator of thermal treeline, we found that around two-thirds of uppermost tree distribution records significantly deviated from it. Drought conditions constitute the primary driver in 51% of cases, followed by mountain elevation effect which indicates surface heat (27%). Our analyses underscore the multifaceted determinants of global patterns of alpine treeline, explaining divergent treeline responses to climate warming. Moisture, along with temperature and disturbance, plays the most fundamental roles in understanding global variation of alpine treeline elevation and forecasting alpine treeline response to ongoing global warming.


Asunto(s)
Ecosistema , Árboles , Árboles/fisiología , Temperatura , Frío , Clima , Altitud
20.
Genet Sel Evol ; 56(1): 26, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565986

RESUMEN

BACKGROUND: Chinese indigenous sheep are valuable resources with unique features and characteristics. They are distributed across regions with different climates in mainland China; however, few reports have analyzed the environmental adaptability of sheep based on their genome. We examined the variants and signatures of selection involved in adaptation to extreme humidity, altitude, and temperature conditions in 173 sheep genomes from 41 phenotypically and geographically representative Chinese indigenous sheep breeds to characterize the genetic basis underlying environmental adaptation in these populations. RESULTS: Based on the analysis of population structure, we inferred that Chinese indigenous sheep are divided into four groups: Kazakh (KAZ), Mongolian (MON), Tibetan (TIB), and Yunnan (YUN). We also detected a set of candidate genes that are relevant to adaptation to extreme environmental conditions, such as drought-prone regions (TBXT, TG, and HOXA1), high-altitude regions (DYSF, EPAS1, JAZF1, PDGFD, and NF1) and warm-temperature regions (TSHR, ABCD4, and TEX11). Among all these candidate genes, eight ABCD4, CNTN4, DOCK10, LOC105608545, LOC121816479, SEM3A, SVIL, and TSHR overlap between extreme environmental conditions. The TSHR gene shows a strong signature for positive selection in the warm-temperature group and harbors a single nucleotide polymorphism (SNP) missense mutation located between positions 90,600,001 and 90,650,001 on chromosome 7, which leads to a change in the protein structure of TSHR and influences its stability. CONCLUSIONS: Analysis of the signatures of selection uncovered genes that are likely related to environmental adaptation and a SNP missense mutation in the TSHR gene that affects the protein structure and stability. It also provides information on the evolution of the phylogeographic structure of Chinese indigenous sheep populations. These results provide important genetic resources for future breeding studies and new perspectives on how animals can adapt to climate change.


Asunto(s)
Genoma , Selección Genética , Ovinos/genética , Animales , China , Análisis de Secuencia de ADN , Altitud , Polimorfismo de Nucleótido Simple
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