ABSTRACT
Obesity is currently one of the most alarming pathological conditions due to the progressive increase in its prevalence. In the last decade, it has been associated with fine particulate matter suspended in the air (PM2.5). The purpose of this study was to explore the mechanistic interaction of PM2.5 with a high-fat diet (HFD) through the differential regulation of transcriptional signatures, aiming to identify the association of these particles with metabolically abnormal obesity. The research design was observational, using bioinformatic methods and an explanatory approach based on Rothman's causal model. We propose three new transcriptional signatures in murine adipose tissue. The sum of transcriptional differences between the group exposed to an HFD and PM2.5, compared to the control group, were 0.851, 0.265, and -0.047 (p > 0.05). The HFD group increased body mass by 20% with two positive biomarkers of metabolic impact. The group exposed to PM2.5 maintained a similar weight to the control group but exhibited three positive biomarkers. Enriched biological pathways (p < 0.05) included PPAR signaling, small molecule transport, adipogenesis genes, cytokine-cytokine receptor interaction, and HIF-1 signaling. Transcriptional regulation predictions revealed CpG islands and common transcription factors. We propose three new transcriptional signatures: FAT-PM2.5-CEJUS, FAT-PM2.5-UP, and FAT-PM2.5-DN, whose transcriptional regulation profile in adipocytes was statistically similar by dietary intake and HFD and exposure to PM2.5 in mice; suggesting a mechanistic interaction between both factors. However, HFD-exposed murines developed moderate metabolically abnormal obesity, and PM2.5-exposed murines developed severe abnormal metabolism without obesity. Therefore, in Rothman's terms, it is concluded that HFD is a sufficient cause of the development of obesity, and PM2.5 is a component cause of severe abnormal metabolism of obesity. These signatures would be integrated into a systemic biological process that would induce transcriptional regulation in trans, activating obesogenic biological pathways, restricting lipid mobilization pathways, decreasing adaptive thermogenesis and angiogenesis, and altering vascular tone thus inducing a severe metabolically abnormal obesity.
ABSTRACT
Kuhn in 1962 establishes the revolutionary character of science: "new scientific theories are not born by verification or falsification, but by substitution." The objective of this review was to analyze the ideas and paradigms through which studies on obesity and its relationship with environmental pollutants, diet and epigenetics have passed, in order to illustrate the current situation of this object of study. Articles were managed in December 2020 from the Web of Science. The strategy was Obesity AND (pollution OR contamination) in the Title field, AND (epigenetic* OR obesity OR food OR nutrition OR diet) in the Themes field. 654 articles were obtained: 577 original investigations and 77 reviews. The documents were exported in BibTeXformat to be quantitatively analyzed with the Bibliometrix program. For the qualitative analysis, review articles were selected in whose titles, keywords and/or abstract, carried the word paradigm*, identifying 19 who underwent content analysis. From 1980 to 2020, four periods were recognized, the first and third are classified as normal science; the second and the fourth, crisis of knowledge or revolution. The evolution of the studies has been differentiated. First, the central theme was environmental pollution and secondarily, obesity. For the second and third period, the epigenetics related to environmental pollution and that associated with obesity are investigated separately and at present, causal relationships between environmental pollutants and obesity, nutrients and epigenetics are hypothesized.
Kuhn en 1962 establece el carácter revolucionario de la ciencia: "las nuevas teorías científicas no nacen por verificación ni por falsación, sino por sustitución". El objetivo de esta revisión fue analizar las ideas y los paradigmas por los que han transitado los estudios sobre obesidad, y su relación con contaminantes ambientales, alimentación y epigenética, con el propósito de ilustrar la situación actual de este objeto de estudio. Se gestionaron artículos en diciembre de 2020 de la Web of Science. La estrategia fue Obesity AND (pollution OR contamination) en el campo Title, AND (epigenetic* OR obesity OR alimentation OR nutrition OR diet) en el campo Themes. Se obtuvieron 654 artículos: 577 investigaciones originales y 77 revisiones. Los documentos se exportaron en formato BibTeX para ser analizados cuantitativamente con el programa Bibliometrix. Para el análisis cualitativo se seleccionaron artículos de revisión en cuyos títulos, palabras clave o resumen llevaran la palabra paradigm*, con lo que se identificaron 19, a los que se les realizó análisis de contenido. De 1980 a 2020 se reconocieron cuatro períodos; el primero y el tercero se clasifican como ciencia normal; el segundo y el cuarto, como crisis de conocimiento o revolución. La evolución de los estudios ha sido diferenciada. Primero, la temática central fue la contaminación ambiental y, de manera secundaria, la obesidad. Para el segundo y el tercer período se investigan por separado la epigenética relacionada con la contaminación ambiental y la asociada con la obesidad, y en la actualidad, se plantean hipótesis de relaciones causales entre contaminantes ambientales y obesidad, nutrientes y epigenética.
Subject(s)
Environmental Pollution , Obesity , World Health Organization , Diet , Environmental Pollutants , Evaluation Studies as Topic , Nutritional Sciences , EpigenomicsABSTRACT
This work discusses some of the important considerations of wild ostrich evolution, behaviour and ecology, as items included in ostrich production. In the process considerable research was conducted by collating information from peer-reviewed papers; textbooks; manuals; and PubMed and Agricola searches. Selected areas reviewed included activity of ostriches; feeding and water needs; sexual maturity; egg laying and natural incubation; selected physiological parameters; and predation. There is an immediate and urgent need to conserve and protect the rapidly declining populations of wild ostriches with the committed involvement of governments and funding bodies.
