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1.
Am J Physiol Gastrointest Liver Physiol ; 325(5): G446-G452, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37697930

RESUMEN

Intestinal inflammation and diarrhea are often associated with SARS-CoV-2 infection. The angiotensin converting enzyme 2 (ACE2) receptor plays a key role in SARS-CoV-2 pathogenesis, facilitating entry of the virus into epithelial cells, while also regulating mucosal inflammatory responses. Here, we investigated roles for the nuclear bile acid receptor farnesoid X receptor (FXR) in regulating ACE2 expression and virally mediated inflammatory responses in intestinal epithelia. Human colonic or ileal enteroids and cultured T84 and Caco-2 monolayers were treated with the FXR agonists, obeticholic acid (OCA) or GW4064, or infected with live SARS-CoV-2 (2019-nCoV/USA_WA1/2020). Changes in mRNA, protein, or secreted cytokines were measured by qPCR, Western blotting, and ELISA. Treatment of undifferentiated colonic or ileal enteroids with OCA increased ACE2 mRNA by 2.1 ± 0.4-fold (n = 3; P = 0.08) and 2.3 ± 0.2-fold (n = 3; P < 0.05), respectively. In contrast, ACE2 expression in differentiated enteroids was not significantly altered. FXR activation in cultured epithelial monolayers also upregulated ACE2 mRNA, accompanied by increases in ACE2 expression and secretion. Further experiments revealed FXR activation to inhibit IL-6 release from both Caco-2 cells infected with SARS-CoV-2 and T84 cells treated with the viral mimic, polyinosinic:polycytidylic acid, by 46 ± 12% (n = 3, P < 0.05) and 35 ± 6% (n = 8; P < 0.01), respectively. By virtue of its ability to modulate epithelial ACE2 expression and inhibit virus-mediated proinflammatory cytokine release, FXR represents a promising target for the development of new approaches to prevent intestinal manifestations of SARS-CoV-2.NEW & NOTEWORTHY Activation of the nuclear bile acid receptor, farnesoid X receptor (FXR), specifically upregulates ACE2 expression in undifferentiated colonic epithelial cells and inhibits virus-induced proinflammatory cytokine release. By virtue of these actions FXR represents a promising target for the development of new approaches to prevent intestinal manifestations of SARS-CoV-2 infection.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Interleucina-6 , Humanos , Enzima Convertidora de Angiotensina 2/metabolismo , Células CACO-2 , Citocinas , Interleucina-6/metabolismo , ARN Mensajero , SARS-CoV-2 , Receptores Citoplasmáticos y Nucleares/metabolismo
2.
PLoS One ; 18(1): e0279556, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36701403

RESUMEN

The power harnessed by cattle traction was undeniably a valuable asset to Neolithic communities. However, data are still lacking on the timing, purposes, and intensity of exploitation of draught animals. This paper sheds new light on a region of Europe-Neolithic Ireland-for which our knowledge is particularly restricted as evidence from both Ireland and Britain in this period has been so far patchy and inconclusive. Using a suite of methods and refined criteria for traction identification, we present new and robust data on a large faunal assemblage from Kilshane, Co. Dublin that strongly support cattle traction in the middle 4th millennium BC in Ireland. Bone pathology data combined with osteometric analysis highlight specialised husbandry practices, producing large males, possibly oxen, for the purpose of cattle traction. This new technology has important implications for early agriculture in the region since it provides a key support for more extensive land management practices as well as for megalithic construction, which increased considerably in scale during this period. We argue that access to draught animals and the exploitation of associated resources were at the heart of wider changes that took place in Neolithic Ireland in the second half of the 4th millennium BC.


Asunto(s)
Agricultura , Tracción , Masculino , Animales , Bovinos , Historia Antigua , Irlanda , Europa (Continente) , Huesos , Arqueología
3.
J Biol Chem ; 298(11): 102569, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36209824

RESUMEN

The nuclear bile acid receptor, farnesoid X receptor (FXR), is an important regulator of intestinal and metabolic function. Previous studies suggest that pentacyclic triterpenes (PCTs), a class of plant-derived bioactive phytochemical, can modulate FXR activity and may therefore offer therapeutic benefits. Here, we investigated the effects of a prototypical PCT, hederagenin (HG), on FXR expression, activity, and antisecretory actions in colonic epithelial cells. T84 cells and murine enteroid-derived monolayers were employed to assess HG effects on FXR expression and activity in colonic epithelia. We measured mRNA levels by qRT-PCR and protein by ELISA and immunoblotting. Transepithelial Cl- secretion was assessed as changes in short circuit current in Ussing chambers. We determined HG treatment (5-10 µM) alone did not induce FXR activation but significantly increased expression of the receptor, both in T84 cells and murine enteroid-derived monolayers. This effect was accompanied by enhanced FXR activity, as assessed by FGF-15/19 induction in response to the synthetic, GW4064, or natural FXR agonist, chenodeoxycholic acid. Effects of HG on FXR expression and activity were mimicked by another PCT, oleanolic acid. Furthermore, we found FXR-induced downregulation of cystic fibrosis transmembrane conductance regulator Cl- channels and inhibition of transepithelial Cl- secretion were enhanced in HG-treated cells. These data demonstrate that dietary PCTs have the capacity to modulate FXR expression, activity, and antisecretory actions in colonic epithelial cells. Based on these data, we propose that plants rich in PCTs, or extracts thereof, have excellent potential for development as a new class of "FXR-targeted nutraceuticals".


Asunto(s)
Ácido Quenodesoxicólico , Colon , Ratones , Animales , Triterpenos Pentacíclicos/farmacología , Triterpenos Pentacíclicos/metabolismo , Colon/metabolismo , Ácido Quenodesoxicólico/farmacología , Células Epiteliales/metabolismo , Mucosa Intestinal/metabolismo
5.
Nature ; 608(7922): 336-345, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35896751

RESUMEN

In European and many African, Middle Eastern and southern Asian populations, lactase persistence (LP) is the most strongly selected monogenic trait to have evolved over the past 10,000 years1. Although the selection of LP and the consumption of prehistoric milk must be linked, considerable uncertainty remains concerning their spatiotemporal configuration and specific interactions2,3. Here we provide detailed distributions of milk exploitation across Europe over the past 9,000 years using around 7,000 pottery fat residues from more than 550 archaeological sites. European milk use was widespread from the Neolithic period onwards but varied spatially and temporally in intensity. Notably, LP selection varying with levels of prehistoric milk exploitation is no better at explaining LP allele frequency trajectories than uniform selection since the Neolithic period. In the UK Biobank4,5 cohort of 500,000 contemporary Europeans, LP genotype was only weakly associated with milk consumption and did not show consistent associations with improved fitness or health indicators. This suggests that other reasons for the beneficial effects of LP should be considered for its rapid frequency increase. We propose that lactase non-persistent individuals consumed milk when it became available but, under conditions of famine and/or increased pathogen exposure, this was disadvantageous, driving LP selection in prehistoric Europe. Comparison of model likelihoods indicates that population fluctuations, settlement density and wild animal exploitation-proxies for these drivers-provide better explanations of LP selection than the extent of milk exploitation. These findings offer new perspectives on prehistoric milk exploitation and LP evolution.


Asunto(s)
Arqueología , Industria Lechera , Enfermedad , Genética de Población , Lactasa , Leche , Selección Genética , Animales , Animales Salvajes , Bancos de Muestras Biológicas , Cerámica/historia , Estudios de Cohortes , Industria Lechera/historia , Europa (Continente)/epidemiología , Europa (Continente)/etnología , Hambruna/estadística & datos numéricos , Frecuencia de los Genes , Genotipo , Historia Antigua , Humanos , Lactasa/genética , Leche/metabolismo , Reino Unido
6.
Physiol Rep ; 8(12): e14456, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32562381

RESUMEN

Increased epithelial permeability is a key feature of IBD pathogenesis and it has been proposed that agents which promote barrier function may be of therapeutic benefit. We have previously reported the secondary bile acid, ursodeoxycholic acid (UDCA), to be protective in a mouse model of colonic inflammation and that its bacterial metabolism is required for its beneficial effects. The current study aimed to compare the effects of UDCA, LCA, and a non-metabolizable analog of UDCA, 6-methyl-UDCA (6-MUDCA), on colonic barrier function and mucosal inflammation in a mouse model of colonic inflammation. Bile acids were administered daily to C57Bl6 mice by intraperitoneal injection. Colonic inflammation, induced by addition of DSS (2.5%) to the drinking water, was measured as disease activity index (DAI) and histological score. Epithelial permeability and apoptosis were assessed by measuring FITC-dextran uptake and caspase-3 cleavage, respectively. Cecal bile acids were measured by HPLC-MS/MS. UDCA and LCA, but not 6-MUDCA, were protective against DSS-induced increases in epithelial permeability and colonic inflammation. Furthermore, UDCA and LCA inhibited colonic epithelial caspase-3 cleavage both in DSS-treated mice and in an in vitro model of cytokine-induced epithelial injury. HPLC-MS/MS analysis revealed UDCA administration to increase colonic LCA levels, whereas LCA administration did not alter UDCA levels. UDCA, and its primary metabolite, LCA, protect against intestinal inflammation in vivo, at least in part, by inhibition of epithelial apoptosis and promotion of barrier function. These data suggest that clinical trials of UDCA in IBD patients are warranted.


Asunto(s)
Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Mucosa Intestinal/efectos de los fármacos , Ácido Litocólico/farmacología , Sustancias Protectoras/farmacología , Ácido Ursodesoxicólico/farmacología , Animales , Apoptosis/efectos de los fármacos , Colagogos y Coleréticos/farmacología , Detergentes/farmacología , Modelos Animales de Enfermedad , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Permeabilidad
7.
Nature ; 580(7804): 506-510, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32322061

RESUMEN

Pottery is one of the most commonly recovered artefacts from archaeological sites. Despite more than a century of relative dating based on typology and seriation1, accurate dating of pottery using the radiocarbon dating method has proven extremely challenging owing to the limited survival of organic temper and unreliability of visible residues2-4. Here we report a method to directly date archaeological pottery based on accelerator mass spectrometry analysis of 14C in absorbed food residues using palmitic (C16:0) and stearic (C18:0) fatty acids purified by preparative gas chromatography5-8. We present accurate compound-specific radiocarbon determinations of lipids extracted from pottery vessels, which were rigorously evaluated by comparison with dendrochronological dates9,10 and inclusion in site and regional chronologies that contained previously determined radiocarbon dates on other materials11-15. Notably, the compound-specific dates from each of the C16:0 and C18:0 fatty acids in pottery vessels provide an internal quality control of the results6 and are entirely compatible with dates for other commonly dated materials. Accurate radiocarbon dating of pottery vessels can reveal: (1) the period of use of pottery; (2) the antiquity of organic residues, including when specific foodstuffs were exploited; (3) the chronology of sites in the absence of traditionally datable materials; and (4) direct verification of pottery typochronologies. Here we used the method to date the exploitation of dairy and carcass products in Neolithic vessels from Britain, Anatolia, central and western Europe, and Saharan Africa.


Asunto(s)
Arqueología/métodos , Cerámica/química , Cerámica/historia , Datación Radiométrica/métodos , Datación Radiométrica/normas , África del Norte , Arqueología/normas , Teorema de Bayes , Radioisótopos de Carbono , Europa (Continente) , Ácidos Grasos/química , Ácidos Grasos/aislamiento & purificación , Alimentos/historia , Historia Antigua , Lípidos/química , Lípidos/aislamiento & purificación , Espectrometría de Masas
8.
Sci Rep ; 9(1): 4559, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30872699

RESUMEN

Bog butters are large white or yellow waxy deposits regularly discovered within the peat bogs of Ireland and Scotland. They represent an extraordinary survival of prehistoric and later agricultural products, comprising the largest deposits of fat found anywhere in nature. Often found in wooden containers or wrapped in animal bladders, they are considered to have been buried intentionally by past farming communities. While previous analysis has determined that Irish bog butters derive from animal fat, their precise characterisation could not be achieved due to diagenetic compositional alterations during burial. Via compound-specific stable isotope analysis, we provide the first conclusive evidence of a dairy fat origin for the Irish bog butter tradition, which differs from bog butter traditions observed elsewhere. Our research also reveals a remarkably long-lived tradition of deposition and possible curation spanning at least 3500 years, from the Early Bronze Age (c. 1700 BC) to the 17th century AD. This is conclusively established via an extensive suite of both bulk and compound-specific radiocarbon dates.


Asunto(s)
Radioisótopos de Carbono/análisis , Productos Lácteos/análisis , Monitoreo del Ambiente/historia , Grasas/análisis , Datación Radiométrica/métodos , Contaminantes del Suelo/análisis , Suelo/química , Agricultura , Animales , Entierro , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia Medieval , Humedales
9.
Nature ; 527(7577): 226-30, 2015 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-26560301

RESUMEN

The pressures on honeybee (Apis mellifera) populations, resulting from threats by modern pesticides, parasites, predators and diseases, have raised awareness of the economic importance and critical role this insect plays in agricultural societies across the globe. However, the association of humans with A. mellifera predates post-industrial-revolution agriculture, as evidenced by the widespread presence of ancient Egyptian bee iconography dating to the Old Kingdom (approximately 2400 BC). There are also indications of Stone Age people harvesting bee products; for example, honey hunting is interpreted from rock art in a prehistoric Holocene context and a beeswax find in a pre-agriculturalist site. However, when and where the regular association of A. mellifera with agriculturalists emerged is unknown. One of the major products of A. mellifera is beeswax, which is composed of a complex suite of lipids including n-alkanes, n-alkanoic acids and fatty acyl wax esters. The composition is highly constant as it is determined genetically through the insect's biochemistry. Thus, the chemical 'fingerprint' of beeswax provides a reliable basis for detecting this commodity in organic residues preserved at archaeological sites, which we now use to trace the exploitation by humans of A. mellifera temporally and spatially. Here we present secure identifications of beeswax in lipid residues preserved in pottery vessels of Neolithic Old World farmers. The geographical range of bee product exploitation is traced in Neolithic Europe, the Near East and North Africa, providing the palaeoecological range of honeybees during prehistory. Temporally, we demonstrate that bee products were exploited continuously, and probably extensively in some regions, at least from the seventh millennium cal BC, likely fulfilling a variety of technological and cultural functions. The close association of A. mellifera with Neolithic farming communities dates to the early onset of agriculture and may provide evidence for the beginnings of a domestication process.


Asunto(s)
Apicultura/historia , Abejas , Ceras/análisis , Ceras/historia , África del Norte , Animales , Arqueología , Cerámica/química , Cerámica/historia , Europa (Continente) , Agricultores/historia , Mapeo Geográfico , Historia Antigua , Lípidos/análisis , Lípidos/química , Medio Oriente , Análisis Espacio-Temporal , Ceras/química
10.
Proc Biol Sci ; 281(1780): 20132372, 2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24523264

RESUMEN

The appearance of farming, from its inception in the Near East around 12 000 years ago, finally reached the northwestern extremes of Europe by the fourth millennium BC or shortly thereafter. Various models have been invoked to explain the Neolithization of northern Europe; however, resolving these different scenarios has proved problematic due to poor faunal preservation and the lack of specificity achievable for commonly applied proxies. Here, we present new multi-proxy evidence, which qualitatively and quantitatively maps subsistence change in the northeast Atlantic archipelagos from the Late Mesolithic into the Neolithic and beyond. A model involving significant retention of hunter-gatherer-fisher influences was tested against one of the dominant adoptions of farming using a novel suite of lipid biomarkers, including dihydroxy fatty acids, ω-(o-alkylphenyl)alkanoic acids and stable carbon isotope signatures of individual fatty acids preserved in cooking vessels. These new findings, together with archaeozoological and human skeletal collagen bulk stable carbon isotope proxies, unequivocally confirm rejection of marine resources by early farmers coinciding with the adoption of intensive dairy farming. This pattern of Neolithization contrasts markedly to that occurring contemporaneously in the Baltic, suggesting that geographically distinct ecological and cultural influences dictated the evolution of subsistence practices at this critical phase of European prehistory.


Asunto(s)
Industria Lechera , Actividades Humanas , Agricultura , Animales , Arqueología , Isótopos de Carbono , Peces , Humanos
12.
Laryngoscope ; 121(9): 1881-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21997727

RESUMEN

OBJECTIVES/HYPOTHESIS: Although treatment paradigms have shifted to recommend primary chemoradiation therapy (CRT) for advanced head and neck squamous cell carcinoma, few studies include any significant number of patients with N3 (>6 cm) neck disease. The objective of this study was to determine if primary chemoradiation therapy has equivalent overall survival (OS) and disease-free survival (DFS) when compared to primary surgical resection in patients with N3 neck disease. STUDY DESIGN: Nonrandomized, single-institution, retrospective cohort study. METHODS: Retrospective analysis of 100 patients treated for HNSCC with N3 neck disease between 1989 and 2009 was performed. RESULTS: Patients who received primary surgery had better OS and DFS than those who had primary chemoradiation (P = .047), with a 5-year OS of 68% (95% confidence interval [CI], 45%-84%) versus 32% (95% CI, 19%-45%), and a 5-year DFS of 64% (95% CI, 41%-80%) versus 32% (95% CI, 19%-45%). Neck dissection following primary treatment with CRT did not improve OS. For patients with nonoropharyngeal squamous cell carcinoma with N3 neck disease, those who underwent primary surgery (n = 14) had significantly better OS than those who had primary CRT (n = 32, P = .02). Patients with oropharyngeal disease had better outcomes than other sites regardless of treatment modality, with 5-year OS of 54% (95% CI, 38%-68%) versus 32% (95% CI, 17%-47%, P = .02), but there was no statistical difference between patients treated with primary surgery versus CRT. CONCLUSIONS: Patients with head and neck squamous cell cancer and N3 neck disease have at least equivalent survival with primary surgical treatment versus primary CRT. Primary surgical resection with appropriate adjuvant therapy should be considered for patients with resectable N3 disease, especially patients with nonoropharyngeal sites. Post-CRT neck dissections did not change the OS of patients with N3 disease.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Terapia Combinada , Femenino , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Disección del Cuello , Estudios Retrospectivos , Estadísticas no Paramétricas , Tasa de Supervivencia , Resultado del Tratamiento
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