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Luppi AI, Rosas FE, Noonan MP, Mediano PAM, Kringelbach ML, Carhart-Harris RL, Stamatakis EA, Vernon AC, Turkheimer FE. Oxygen and the Spark of Human Brain Evolution: Complex Interactions of Metabolism and Cortical Expansion across Development and Evolution. Neuroscientist 2024; 30:173-198. [PMID: 36476177 DOI: 10.1177/10738584221138032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Scientific theories on the functioning and dysfunction of the human brain require an understanding of its development-before and after birth and through maturation to adulthood-and its evolution. Here we bring together several accounts of human brain evolution by focusing on the central role of oxygen and brain metabolism. We argue that evolutionary expansion of human transmodal association cortices exceeded the capacity of oxygen delivery by the vascular system, which led these brain tissues to rely on nonoxidative glycolysis for additional energy supply. We draw a link between the resulting lower oxygen tension and its effect on cytoarchitecture, which we posit as a key driver of genetic developmental programs for the human brain-favoring lower intracortical myelination and the presence of biosynthetic materials for synapse turnover. Across biological and temporal scales, this protracted capacity for neural plasticity sets the conditions for cognitive flexibility and ongoing learning, supporting complex group dynamics and intergenerational learning that in turn enabled improved nutrition to fuel the metabolic costs of further cortical expansion. Our proposed model delineates explicit mechanistic links among metabolism, molecular and cellular brain heterogeneity, and behavior, which may lead toward a clearer understanding of brain development and its disorders.
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Affiliation(s)
- Andrea I Luppi
- Department of Clinical Neurosciences and Division of Anaesthesia, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Leverhulme Centre for the Future of Intelligence, University of Cambridge, Cambridge, UK
- The Alan Turing Institute, London, UK
| | - Fernando E Rosas
- Department of Informatics, University of Sussex, Brighton, UK
- Centre for Psychedelic Research, Department of Brain Science, Imperial College London, London, UK
- Centre for Complexity Science, Imperial College London, London, UK
- Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, UK
| | - MaryAnn P Noonan
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Pedro A M Mediano
- Department of Psychology, University of Cambridge, Cambridge, UK
- Department of Psychology, Queen Mary University of London, London, UK
- Department of Computing, Imperial College London, London, UK
| | - Morten L Kringelbach
- Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, UK
- Center for Music in the Brain, Aarhus University, Aarhus, Denmark
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Robin L Carhart-Harris
- Psychedelics Division-Neuroscape, Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Emmanuel A Stamatakis
- Department of Clinical Neurosciences and Division of Anaesthesia, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Anthony C Vernon
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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Zintel TM, Pizzollo J, Claypool CG, Babbitt CC. Astrocytes Drive Divergent Metabolic Gene Expression in Humans and Chimpanzees. Genome Biol Evol 2024; 16:evad239. [PMID: 38159045 PMCID: PMC10829071 DOI: 10.1093/gbe/evad239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 11/13/2023] [Accepted: 12/23/2023] [Indexed: 01/03/2024] Open
Abstract
The human brain utilizes ∼20% of all of the body's metabolic resources, while chimpanzee brains use <10%. Although previous work shows significant differences in metabolic gene expression between the brains of primates, we have yet to fully resolve the contribution of distinct brain cell types. To investigate cell type-specific interspecies differences in brain gene expression, we conducted RNA-seq on neural progenitor cells, neurons, and astrocytes generated from induced pluripotent stem cells from humans and chimpanzees. Interspecies differential expression analyses revealed that twice as many genes exhibit differential expression in astrocytes (12.2% of all genes expressed) than neurons (5.8%). Pathway enrichment analyses determined that astrocytes, rather than neurons, diverged in expression of glucose and lactate transmembrane transport, as well as pyruvate processing and oxidative phosphorylation. These findings suggest that astrocytes may have contributed significantly to the evolution of greater brain glucose metabolism with proximity to humans.
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Affiliation(s)
- Trisha M Zintel
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA, USA
| | - Jason Pizzollo
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA, USA
| | - Christopher G Claypool
- Organismic and Evolutionary Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA, USA
| | - Courtney C Babbitt
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA, USA
- Organismic and Evolutionary Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA, USA
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3
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Bryant KL, Hansen C, Hecht EE. Fermentation technology as a driver of human brain expansion. Commun Biol 2023; 6:1190. [PMID: 37996482 PMCID: PMC10667226 DOI: 10.1038/s42003-023-05517-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 10/27/2023] [Indexed: 11/25/2023] Open
Abstract
Brain tissue is metabolically expensive. Consequently, the evolution of humans' large brains must have occurred via concomitant shifts in energy expenditure and intake. Proposed mechanisms include dietary shifts such as cooking. Importantly, though, any new food source must have been exploitable by hominids with brains a third the size of modern humans'. Here, we propose the initial metabolic trigger of hominid brain expansion was the consumption of externally fermented foods. We define "external fermentation" as occurring outside the body, as opposed to the internal fermentation in the gut. External fermentation could increase the bioavailability of macro- and micronutrients while reducing digestive energy expenditure and is supported by the relative reduction of the human colon. We discuss the explanatory power of our hypothesis and survey external fermentation practices across human cultures to demonstrate its viability across a range of environments and food sources. We close with suggestions for empirical tests.
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Affiliation(s)
- Katherine L Bryant
- Laboratoire de Psychologie Cognitive, Aix-Marseille Université, Marseille, France.
| | - Christi Hansen
- Hungry Heart Farm and Dietary Consulting, Conley, GA, USA
| | - Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA.
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Sixtus RP, Bailey DM. Burning fuels burns the brain's bioenergetic bridges: On the importance of physiological resilience. Exp Physiol 2023; 108:1366-1369. [PMID: 37742138 PMCID: PMC10988455 DOI: 10.1113/ep091424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 09/11/2023] [Indexed: 09/25/2023]
Affiliation(s)
- Ryan P. Sixtus
- School of Biomedical Sciences, Sir Martin Evans BuildingCardiff UniversityGlamorganUK
| | - Damian M. Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesGlamorganUK
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Longman DP, Wells JCK, Stock JT. Human energetic stress associated with upregulation of spatial cognition. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 182:32-44. [PMID: 37494592 DOI: 10.1002/ajpa.24820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 06/12/2023] [Accepted: 07/09/2023] [Indexed: 07/28/2023]
Abstract
OBJECTIVES Evolutionary life history theory has a unique potential to shed light on human adaptive capabilities. Ultra-endurance challenges are a valuable experimental model allowing the direct testing of phenotypic plasticity via physiological trade-offs in resource allocation. This enhances our understanding of how the body prioritizes different functions when energetically stressed. However, despite the central role played by the brain in both hominin evolution and metabolic budgeting, cognitive plasticity during energetic deficit remains unstudied. MATERIALS We considered human cognitive plasticity under conditions of energetic deficit by evaluating variability in performance in three key cognitive domains. To achieve this, cognitive performance in a sample of 48 athletes (m = 29, f = 19) was assessed before and after competing in multiday ultramarathons. RESULTS We demonstrate that under conditions of energetic deficit, performance in tasks of spatial working memory (which assessed ability to store location information, promoting landscape navigation and facilitating resource location and calorie acquisition) increased. In contrast, psychomotor speed (reaction time) remained unchanged and episodic memory performance (ability to recall information about specific events) decreased. DISCUSSION We propose that prioritization of spatial working memory performance during conditions of negative energy balance represents an adaptive response due to its role in facilitating calorie acquisition. We discuss these results with reference to a human evolutionary trajectory centred around encephalisation. Encephalisation affords great plasticity, facilitating rapid responses tailored to specific environmental conditions, and allowing humans to increase their capabilities as a phenotypically plastic species.
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Affiliation(s)
- Daniel P Longman
- School of Sport, Health and Exercise Sciences, Loughborough University, Loughborough, UK
- ISSUL, Institute of Sport Science, University of Lausanne, Lausanne, Vaud, Switzerland
| | - Jonathan C K Wells
- Childhood Nutrition Research Centre, UCL Institute of Child Health, London, UK
| | - Jay T Stock
- Department of Anthropology, University of Western Ontario, London, Ontario, Canada
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Urlacher SS. The energetics of childhood: Current knowledge and insights into human variation, evolution, and health. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023. [PMID: 36866969 DOI: 10.1002/ajpa.24719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/22/2022] [Accepted: 02/10/2023] [Indexed: 03/04/2023]
Abstract
How organisms capture and ultimately use metabolic energy-a limiting resource of life-has profound implications for understanding evolutionary legacies and current patterns of phenotypic variation, adaptation, and health. Energetics research among humans has a rich history in biological anthropology and beyond. The energetics of childhood, however, remains relatively underexplored. This shortcoming is notable given the accepted importance of childhood in the evolution of the unique human life history pattern as well as the known sensitivity of childhood development to local environments and lived experiences. In this review, I have three objectives: (1) To overview current knowledge regarding how children acquire and use energy, highlighting work among diverse human populations and pointing to recent advances and remaining areas of uncertainty; (2) To discuss key applications of this knowledge for understanding human variation, evolution, and health; (3) To recommend future avenues for research. A growing body of evidence supports a model of trade-offs and constraint in childhood energy expenditure. This model, combined with advancements on topics such as the energetics of immune activity, the brain, and the gut, provides insights into the evolution of extended human subadulthood and the nature of variation in childhood development, lifetime phenotype, and health.
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Affiliation(s)
- Samuel S Urlacher
- Department of Anthropology, Baylor University, Waco, Texas, USA
- Child and Brain Development Program, CIFAR, Toronto, Canada
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Clemente-Suárez VJ, Mielgo-Ayuso J, Martín-Rodríguez A, Ramos-Campo DJ, Redondo-Flórez L, Tornero-Aguilera JF. The Burden of Carbohydrates in Health and Disease. Nutrients 2022; 14:3809. [PMID: 36145184 PMCID: PMC9505863 DOI: 10.3390/nu14183809] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
Foods high in carbohydrates are an important part of a healthy diet, since they provide the body with glucose to support bodily functions and physical activity. However, the abusive consumption of refined, simple, and low-quality carbohydrates has a direct implication on the physical and mental pathophysiology. Then, carbohydrate consumption is postulated as a crucial factor in the development of the main Western diseases of the 21st century. We conducted this narrative critical review using MedLine (Pubmed), Cochrane (Wiley), Embase, and CinAhl databases with the MeSH-compliant keywords: carbohydrates and evolution, development, phylogenetic, GUT, microbiota, stress, metabolic health, consumption behaviors, metabolic disease, cardiovascular disease, mental disease, anxiety, depression, cancer, chronic kidney failure, allergies, and asthma in order to analyze the impact of carbohydrates on health. Evidence suggests that carbohydrates, especially fiber, are beneficial for the well-being and growth of gut microorganisms and consequently for the host in this symbiotic relationship, producing microbial alterations a negative effect on mental health and different organic systems. In addition, evidence suggests a negative impact of simple carbohydrates and refined carbohydrates on mood categories, including alertness and tiredness, reinforcing a vicious circle. Regarding physical health, sugar intake can affect the development and prognosis of metabolic disease, as an uncontrolled intake of refined carbohydrates puts individuals at risk of developing metabolic syndrome and subsequently developing metabolic disease.
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Affiliation(s)
- Vicente Javier Clemente-Suárez
- Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, s/n, 28670 Madrid, Spain
- Grupo de Investigación en Cultura, Educación y Sociedad, Universidad de la Costa, Barranquilla 080002, Colombia
- Studies Centre in Applied Combat (CESCA), 45007 Toledo, Spain
| | - Juan Mielgo-Ayuso
- Department of Health Sciences, Faculty of Health Sciences, University of Burgos, 09001 Burgos, Spain
| | | | - Domingo Jesús Ramos-Campo
- LFE Research Group, Department of Health and Human Performance, Faculty of Physical Activity and Sport Science-INEF, Universidad Politécnica de Madrid, 28670 Madrid, Spain
| | - Laura Redondo-Flórez
- Department of Health Sciences, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, C/Tajo, s/n, Villaviciosa de Odón, 28670 Madrid, Spain
| | - Jose Francisco Tornero-Aguilera
- Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, s/n, 28670 Madrid, Spain
- Studies Centre in Applied Combat (CESCA), 45007 Toledo, Spain
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Saxena S, Hosken DJ, Dutta T. Digest: Brain or brawn: Trade-offs between brain size and flight mode in birds. Evolution 2022; 76:1916-1918. [PMID: 35767581 DOI: 10.1111/evo.14548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 06/15/2022] [Indexed: 01/22/2023]
Abstract
Brain size is extremely variable across species, and its evolution depends upon the calorific trade-offs between it and other organs and activities. Shiomi investigated potential brain size trade-offs with different flight modes in birds. Flight can be energetically expensive, and costs are especially high with powered flight. This comparative study indicated that migratory birds employing less energetic modes of flight had relatively larger brains than migratory birds using powered flight, suggesting that brain size is impacted by the energetic costs of flight.
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Affiliation(s)
- Swati Saxena
- Department of Zoology, University of Lucknow, Lucknow, 226007, India
| | - David J Hosken
- Centre for Ecology and Conservation, University of Exeter, Penryn, TR10 9EZ, United Kingdom
| | - Tusheema Dutta
- Vanasiri Evolutionary Ecology Lab, School of Biology, IISER, Thiruvananthapuram, 695551, India
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de Jager E, Prigge L, Amod N, Oettlé A, Beaudet A. Exploring the relationship between soft and hard tissues: The example of vertebral arteries and transverse foramina. J Anat 2022; 241:447-452. [PMID: 35468222 PMCID: PMC9296038 DOI: 10.1111/joa.13681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/23/2022] [Accepted: 04/12/2022] [Indexed: 11/29/2022] Open
Abstract
Understanding how the brain is provided with glucose and oxygen is of particular interest in human evolutionary studies. In addition to the internal carotid arteries, vertebral arteries contribute significantly to the cerebral and cerebellar blood flow. The size of the transverse foramina has been suggested to represent a reliable proxy for assessing the size of the vertebral arteries in fossil specimens. To test this assumption, here, we statistically explore spatial relationships between the transverse foramina and the vertebral arteries in extant humans. Contrast computed tomography (CT) scans of the cervical regions of 16 living humans were collected. Cross-sectional areas of the right and left transverse foramina and the corresponding vertebral arteries were measured on each cervical vertebra from C1 to C6 within the same individuals. The cross-sectional areas of the foramina and corresponding arteries range between 13.40 and 71.25 mm2 and between 4.53 and 29.40 mm2 , respectively. The two variables are significantly correlated except in C1. Using regression analyses, we generate equations that can be subsequently used to estimate the size of the vertebral arteries in fossil specimens. By providing additional evidence of intra- and inter-individual size variation of the arteries and corresponding foramina in extant humans, our study introduces an essential database for a better understanding of the evolutionary story of soft tissues in the fossil record.
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Affiliation(s)
- Edwin de Jager
- Department of Archaeology, University of Cambridge, Cambridge, UK
| | - Lané Prigge
- Department of Anatomy, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa.,Department of Anatomy, University of Pretoria, Pretoria, South Africa
| | - Nooreen Amod
- Department of Radiology, Dr George Mukhari Academic Hospital, Ga-Rankuwa, South Africa
| | - Anna Oettlé
- Department of Anatomy, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa.,Department of Anatomy, University of Pretoria, Pretoria, South Africa
| | - Amélie Beaudet
- Department of Archaeology, University of Cambridge, Cambridge, UK.,School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, South Africa.,Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Barcelona, Spain
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You W, Henneberg R, Saniotis A, Ge Y, Henneberg M. Total Meat Intake is Associated with Life Expectancy: A Cross-Sectional Data Analysis of 175 Contemporary Populations. Int J Gen Med 2022; 15:1833-1851. [PMID: 35228814 PMCID: PMC8881926 DOI: 10.2147/ijgm.s333004] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/30/2021] [Indexed: 01/08/2023] Open
Abstract
Background The association between a plant-based diet (vegetarianism) and extended life span is increasingly criticised since it may be based on the lack of representative data and insufficient removal of confounders such as lifestyles. Aim We examined the association between meat intake and life expectancy at a population level based on ecological data published by the United Nations agencies. Methods Population-specific data were obtained from 175 countries/territories. Scatter plots, bivariate, partial correlation and linear regression models were used with SPSS 25 to explore and compare the correlations between newborn life expectancy (e(0)), life expectancy at 5 years of life (e(5)) and intakes of meat, and carbohydrate crops, respectively. The established risk factors to life expectancy – caloric intake, urbanization, obesity and education levels – were included as the potential confounders. Results Worldwide, bivariate correlation analyses revealed that meat intake is positively correlated with life expectancies. This relationship remained significant when influences of caloric intake, urbanization, obesity, education and carbohydrate crops were statistically controlled. Stepwise linear regression selected meat intake, not carbohydrate crops, as one of the significant predictors of life expectancy. In contrast, carbohydrate crops showed weak and negative correlation with life expectancy. Conclusion If meat intake is not incorporated into nutrition science for predicting human life expectancy, results could prove inaccurate.
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Affiliation(s)
- Wenpeng You
- Biological Anthropology and Comparative Anatomy Research Unit (BACARU), Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- FAPAB Research Center, Avola SR, 96012, Sicily, Italy
- Correspondence: Wenpeng You, Adelaide Medical School, University of Adelaide, Adelaide, SA, 5005, Australia, Email
| | - Renata Henneberg
- Biological Anthropology and Comparative Anatomy Research Unit (BACARU), Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Arthur Saniotis
- Biological Anthropology and Comparative Anatomy Research Unit (BACARU), Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Department of Anthropology, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Yanfei Ge
- Australian Graduate School of Management (Executive MBA Candidate), University of New South Wales, Sydney, New South Wales, Australia
- Community Services, Health & Lifestyle, Technical and Further Education, Adelaide, South Australia, 5000, Australia
| | - Maciej Henneberg
- Biological Anthropology and Comparative Anatomy Research Unit (BACARU), Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Institute of Evolutionary Medicine, University of Zürich, Zurich, Switzerland
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11
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Evolution of cranial capacity revisited: A view from the late Middle Pleistocene cranium from Xujiayao, China. J Hum Evol 2022; 163:103119. [PMID: 35026677 DOI: 10.1016/j.jhevol.2021.103119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 12/11/2022]
Abstract
The Late Middle Pleistocene hominin fossils from the Xujiayao site in northern China have been closely studied in light of their morphological variability. However, all previous studies have focused on separated cranial fragments. Here, we report the first reconstruction of a fairly complete posterior cranium, Xujiayao 6 (XJY 6), confidently dated to ∼200-160 ka, which facilitated an assessment of its overall cranial size. XJY 6 was reconstructed from three of the original fragments-the PA1486 (No.7/XJY 6a) occipital bone, PA1490 (No.10/XJY 6b) right parietal bone, and PA1498 (No.17/XJY 15) left temporal bone-which originated from the same young adult individual. The XJY 6 endocranial capacity, estimated by measuring endocranial volume, was estimated using multiple regression formulae derived from ectocranial and endocranial measurements on select samples of Pleistocene hominins and recent modern humans. The results indicate that the larger pooled sample of both Pleistocene and recent modern humans was more robust for the endocranial capacity estimate. Based on the pooled sample using the ectocranial and endocranial measurements, we conservatively estimate the XJY 6 endocranial volume to be ∼1700 cm3 with a 95% confidence interval of 1555-1781 cm3. This is close to Xuchang 1, which dates to 125-105 ka and whose endocranial volume is ∼1800 cm3. Thus, XJY 6 provides the earliest evidence of a brain size that falls in the upper range of Neanderthals and modern Homo sapiens. XJY 6, together with Xuchang 1, Homo floresiensis, Homo luzonensis, and Homo naledi, challenge the general pattern that brain size gradually increases over geological time. This study also finds that hominin brain size expansion occurred at different rates across time and space.
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12
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Schrock JM, Sugiyama LS, Naidoo N, Kowal P, Snodgrass JJ. Greater chronic morbidity is associated with greater fatigue in six countries. Evol Med Public Health 2022; 10:156-169. [PMID: 35480567 PMCID: PMC9036556 DOI: 10.1093/emph/eoac011] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 03/15/2022] [Indexed: 11/15/2022] Open
Abstract
Background and objectives Human susceptibility to chronic non-communicable disease may be explained, in part, by mismatches between our evolved biology and contemporary environmental conditions. Disease-induced fatigue may function to reduce physical activity during acute infection, thereby making more energy available to mount an effective immune response. However, fatigue in the context of chronic disease may be maladaptive because long-term reductions in physical activity increase risks of disease progression and the acquisition of additional morbidities. Here, we test whether cumulative chronic morbidity is associated with subjective fatigue. Methodology We constructed a cumulative chronic morbidity score using self-reported diagnoses and algorithm-based assessments, and a subjective fatigue score based on four questionnaire items using cross-sectional survey data from the Study on global AGEing and adult health, which features large samples of adults from six countries (China, Ghana, India, Mexico, Russia and South Africa). Results In a mixed-effects linear model with participants nested in countries (N = 32 455), greater cumulative chronic morbidity is associated with greater subjective fatigue (β = 0.34, SE = 0.005, P < 2e−16). This association replicates within each country and is robust to adjustment for key sociodemographic and physical covariates (sex, age, household wealth, physical function score, habitual physical activity, BMI and BMI2). Conclusions and implications Fatigue is a common but perhaps maladaptive neuropsychological response to chronic morbidity. Disease-induced fatigue may mediate a self-perpetuating cycle, in which chronic morbidity reduces physical activity, and less physical activity increases cumulative chronic morbidity. Longitudinal research is needed to test whether chronic morbidity, fatigue and physical activity form a cyclical feedback loop. Lay Summary: Fatigue during acute illness may promote recovery, but persistent fatigue in the context of chronic disease may make matters worse. We present evidence from six countries that more chronic disease is associated with more fatigue. This fatigue may reduce physical activity, which increases risks of acquiring additional chronic health problems.
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Affiliation(s)
- Joshua M Schrock
- Institute for Sexual and Gender Minority Health and Wellbeing, Northwestern University, 625 N Michigan Avenue, Suite 14, Chicago, IL 60611, USA
- Department of Anthropology, Northwestern University, 1810 Hinman Avenue, Evanston, IL 60208, USA
- Department of Anthropology, 1218 University of Oregon, 308 Condon Hall, Eugene, OR 97403, USA
- Corresponding author. Institute for Sexual and Gender Minority Health and Wellbeing, Northwestern University, 625 N Michigan Avenue, Suite 14, Chicago, IL 60611, USA. Tel: (312) 503-5408; E-mail:
| | - Lawrence S Sugiyama
- Department of Anthropology, 1218 University of Oregon, 308 Condon Hall, Eugene, OR 97403, USA
| | - Nirmala Naidoo
- Study on global AGEing and adult health (SAGE), World Health Organization, Avenue Appia 20, Geneva 1211, Switzerland
| | - Paul Kowal
- Study on global AGEing and adult health (SAGE), World Health Organization, Avenue Appia 20, Geneva 1211, Switzerland
- Centre for Women’s Health Research, University Drive, Callaghan, NSW 2308, Australia
| | - J Josh Snodgrass
- Department of Anthropology, 1218 University of Oregon, 308 Condon Hall, Eugene, OR 97403, USA
- Center for Global Health, University of Oregon, 1585 E 13th Avenue, Eugene, OR 97403, USA
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13
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Cusick SE, Barks A, Georgieff MK. Nutrition and Brain Development. Curr Top Behav Neurosci 2022; 53:131-165. [PMID: 34622395 DOI: 10.1007/7854_2021_244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
All nutrients are essential for brain development, but pre-clinical and clinical studies have revealed sensitive periods of brain development during which key nutrients are critical. An understanding of these nutrient-specific sensitive periods and the accompanying brain regions or processes that are developing can guide effective nutrition interventions as well as the choice of meaningful circuit-specific neurobehavioral tests to best determine outcome. For several nutrients including protein, iron, iodine, and choline, pre-clinical and clinical studies align to identify the same sensitive periods, while for other nutrients, such as long-chain polyunsaturated fatty acids, zinc, and vitamin D, pre-clinical models demonstrate benefit which is not consistently shown in clinical studies. This discordance of pre-clinical and clinical results is potentially due to key differences in the timing, dose, and/or duration of the nutritional intervention as well as the pre-existing nutritional status of the target population. In general, however, the optimal window of success for nutritional intervention to best support brain development is in late fetal and early postnatal life. Lack of essential nutrients during these times can lead to long-lasting dysfunction and significant loss of developmental potential.
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Affiliation(s)
- Sarah E Cusick
- Department of Pediatrics, University of Minnesota School of Medicine, Minneapolis, MN, USA.
| | - Amanda Barks
- University of Minnesota Medical School, Minneapolis, MN, USA
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14
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DeSilva JM, Traniello JFA, Claxton AG, Fannin LD. When and Why Did Human Brains Decrease in Size? A New Change-Point Analysis and Insights From Brain Evolution in Ants. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.742639] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Human brain size nearly quadrupled in the six million years since Homo last shared a common ancestor with chimpanzees, but human brains are thought to have decreased in volume since the end of the last Ice Age. The timing and reason for this decrease is enigmatic. Here we use change-point analysis to estimate the timing of changes in the rate of hominin brain evolution. We find that hominin brains experienced positive rate changes at 2.1 and 1.5 million years ago, coincident with the early evolution of Homo and technological innovations evident in the archeological record. But we also find that human brain size reduction was surprisingly recent, occurring in the last 3,000 years. Our dating does not support hypotheses concerning brain size reduction as a by-product of body size reduction, a result of a shift to an agricultural diet, or a consequence of self-domestication. We suggest our analysis supports the hypothesis that the recent decrease in brain size may instead result from the externalization of knowledge and advantages of group-level decision-making due in part to the advent of social systems of distributed cognition and the storage and sharing of information. Humans live in social groups in which multiple brains contribute to the emergence of collective intelligence. Although difficult to study in the deep history of Homo, the impacts of group size, social organization, collective intelligence and other potential selective forces on brain evolution can be elucidated using ants as models. The remarkable ecological diversity of ants and their species richness encompasses forms convergent in aspects of human sociality, including large group size, agrarian life histories, division of labor, and collective cognition. Ants provide a wide range of social systems to generate and test hypotheses concerning brain size enlargement or reduction and aid in interpreting patterns of brain evolution identified in humans. Although humans and ants represent very different routes in social and cognitive evolution, the insights ants offer can broadly inform us of the selective forces that influence brain size.
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15
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Urlacher SS. Child growth and development: new insights from evolutionary energetics. Ann Hum Biol 2021; 48:371-373. [PMID: 34455872 DOI: 10.1080/03014460.2021.1974090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Samuel S Urlacher
- Department of Anthropology, Baylor University, Waco, TX, USA.,Child and Brain Development Program, CIFAR, Toronto, Canada
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16
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Cerrito P, DeCasien AR. The expression of care: Alloparental care frequency predicts neural control of facial muscles in primates. Evolution 2021; 75:1727-1737. [PMID: 34019303 DOI: 10.1111/evo.14275] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 05/02/2021] [Accepted: 05/04/2021] [Indexed: 11/30/2022]
Abstract
The adaptive value of facial expressions has been debated in evolutionary biology ever since Darwin's seminal work. Among mammals, primates, including humans, exhibit the most intricate facial displays. Although previous work has focused on the role of sociality in the evolution of primate facial expressions, this relationship has not been verified in a wide sample of species. Here, we examine the relationship between allomaternal care (paternal or alloparental) and the morphology of three orofacial brainstem nuclei (facial; trigeminal motor; hypoglossal) across primates to test the hypothesis that allomaternal care explains variation in the complexity of facial expressions, proxied by relative facial nucleus size and neuropil fraction. The latter represents the proportion of synaptically dense tissue and may, therefore, correlate with dexterity. We find that alloparental care frequency predicts relative neuropil fraction of the facial nucleus, even after controlling for social system organization, whereas allomaternal care is not associated with the trigeminal motor or hypoglossal nuclei. Overall, this work suggests that alloparenting requires increased facial dexterity to facilitate nonverbal communication between infants and their nonparent caregivers and/or between caregivers. Accordingly, alloparenting and complex facial expressions are likely to have coevolved in primates.
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Affiliation(s)
- Paola Cerrito
- Department of Anthropology, New York University, New York, New York, 10003.,New York Consortium in Evolutionary Primatology, New York, New York, 10024.,Department of Molecular Pathobiology, New York University College of Dentistry, New York, New York, 10010
| | - Alex R DeCasien
- Department of Anthropology, New York University, New York, New York, 10003.,New York Consortium in Evolutionary Primatology, New York, New York, 10024
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17
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Soulier MC. Exploring meat processing in the past: Insights from the Nunamiut people. PLoS One 2021; 16:e0245213. [PMID: 33439906 PMCID: PMC7806178 DOI: 10.1371/journal.pone.0245213] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/23/2020] [Indexed: 11/19/2022] Open
Abstract
Improving our knowledge of subsistence strategies and food processing techniques of past societies is of prime interest for better understanding human cultures as well as multiple aspects of human evolution. Beyond the simple matter of food itself, a substantial portion of socio-economic behavior is expressed in what, how, when, and with whom we eat. Over the last few decades, diverse methodologies for the analysis and interpretation of cut marks have progressively provided new insights for past butchery practices. For example, a recent study of the production of antelope biltong in South Africa concluded that the drying of meat generates high frequencies of longitudinal cut marks. This paper presents a cut mark analysis of faunal remains recovered by Lewis Binford from 8 campsites occupied by Nunamiut groups from the end of 19th to middle of the 20th century in the area around Anaktuvuk Pass, Alaska. The preparation of meat-primarily from caribou (Rangifer tarandus)-varied at these sites according to the season of occupation and was, depending on the site, either immediately consumed, processed after being stored in ice-cellars, or dried and stored. These faunal assemblages therefore provide a unique opportunity to explore the material traces of different meat preparation and preservation techniques in order to identify whether specific patterns can be identified and subsequently used to explore subsistence practices in the past. Binford's Nunamiut faunal assemblages, which were produced by individuals using traditional techniques and methods, were analyzed in order to 1) further test the hypothesis that meat drying produces high frequencies of longitudinal cut marks, 2) explore the common assumption that skilled butchers leave smaller numbers of cut marks on bones compared to less experienced individuals, and 3) test whether cut mark patterns vary as a function of the processing techniques employed. The introduction of a %cutL index represents a quicker alternative to geo-referencing cut marks on bones when exploring meat processing techniques and methods and can easily be integrated in zooarchaeological analyses. While the results obtained support processing techniques linked to meat drying to leave high numbers of longitudinal cut marks, they are inconsistent with cut mark frequencies varying as a function of the butcher's skill and experience. Analyzing cut mark patterns is therefore a reliable means for exploring food processing by past human societies and, by extension, their methods for safeguarding against unfavorable seasonal variations in both the abundance and condition of prey species. Identifying food storage in the archaeological record equally provides a unique window on to the social dynamics and potential inequalities of past societies.
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Affiliation(s)
- Marie-Cécile Soulier
- CNRS UMR 5608 TRACES, Université de Toulouse-Jean Jaurès, Maison de la Recherche, Toulouse, France
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18
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Crowley PH. Self-Deception about Fecundity in Women : Modeling the Burley Hypothesis. HUMAN NATURE (HAWTHORNE, N.Y.) 2020; 31:421-442. [PMID: 33538980 DOI: 10.1007/s12110-020-09384-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
Concealed fecundity and extended female sexual receptivity have evolved in some primates, including humans, conferring advantages both within primarily monogamous relationships (e.g., benefits from paternity assurance) and from extrapair liaisons (e.g., better access to good genes). As humans evolved the intellectual capacity for decision-making, women became capable of altering their own fertility. In some circumstances, they may choose to ameliorate risks and responsibilities associated with pregnancy by reducing sexual motivation near the perceived most fecund time of their menstrual cycle. But three findings-a general inability of women to accurately recognize their own intervals of fecundity, high variability in ovulation timing, and unconscious transmission and reception of cues associated with fecundity-constitute a physiological and behavioral syndrome that can be considered self-deception. In this study, I develop a descriptive model to determine implications of the hypothesis that these features of female and male physiology and behavior have been shaped by natural selection in response to female decision-making. My analysis shows that consensus motivation for coitus between partners influences both the importance of variable ovulation date and the probability of conception, under the influence of self-deception. It also identifies priorities for future empirical work.
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Affiliation(s)
- Philip H Crowley
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA.
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19
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Best AW. Why does strength training improve endurance performance? Am J Hum Biol 2020; 33:e23526. [PMID: 33089638 DOI: 10.1002/ajhb.23526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 09/29/2020] [Accepted: 10/11/2020] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE The specificity of training principle holds that adaptations to exercise training closely match capacity to the specific demands of the stimulus. Improvements in endurance sport performance gained through strength training are a notable exception to this principle. While the proximate mechanisms for how strength training produces muscular adaptations beneficial to endurance sports are increasingly well understood, the ultimate causes of this phenomenon remain unexplored. METHODS Using a holistic approach tying together exercise physiology and evolution, I argue that we can reconcile the apparent "endurance training specificity paradox." RESULTS AND CONCLUSIONS Competing selective pressures, inherited mammalian biology, and millennia of living in energy-scarce environments constrained our evolution as endurance athletes, but also imparted high muscular plasticity which can be exploited to improve endurance performance beyond what was useful in our evolutionary past.
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Affiliation(s)
- Andrew W Best
- Department of Anthropology, University of Massachusetts, Amherst, Massachusetts, USA
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20
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Bailey DM. Oxygen and brain death; back from the brink. Exp Physiol 2020; 104:1769-1779. [PMID: 31605408 DOI: 10.1113/ep088005] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/09/2019] [Indexed: 12/25/2022]
Abstract
NEW FINDINGS • What is the topic of this review? To explore the unique evolutionary origins of the human brain and critically appraise its energy budget, including limits of oxygen and glucose deprivation during anoxia and ischaemia. • What advances does it highlight? The brain appears to be more resilient to substrate depletion than traditionally thought, highlighting greater resilience and an underappreciated capacity for functional recovery. ABSTRACT The human brain has evolved into an unusually large, complex and metabolically expensive organ that relies entirely on a continuous supply of O2 and glucose. It has traditionally been assumed that its exorbitant energy budget, combined with little to no energy reserves, renders it especially vulnerable to anoxia and ischaemia, with substrate depletion and progression towards cell death largely irreversible and rapid. However, new and exciting evidence suggests that neurons can survive for longer than previously thought, highlighting an unexpected resilience and underappreciated capacity for functional recovery that has changed the way we think about brain cell death. Nature has the potential to unlock some of the mysteries underlying ischaemic survival, with select vertebrates having solved the problem of anoxia-hypoxia tolerance over millions of years of evolution. Better understanding of their survival strategies, including remarkable adaptations in brain physiology and redox homeostasis, might help to identify new therapeutic targets for human diseases characterized by O2 deprivation, ischaemia-reperfusion injury and ageing.
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Affiliation(s)
- Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, Glamorgan, UK
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21
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Bauernfeind AL, Babbitt CC. Metabolic changes in human brain evolution. Evol Anthropol 2020; 29:201-211. [PMID: 32329960 DOI: 10.1002/evan.21831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/30/2019] [Accepted: 03/13/2020] [Indexed: 12/23/2022]
Abstract
Because the human brain is considerably larger than those of other primates, it is not surprising that its energy requirements would far exceed that of any of the species within the order. Recently, the development of stem cell technologies and single-cell transcriptomics provides novel ways to address the question of what specific genomic changes underlie the human brain's unique phenotype. In this review, we consider what is currently known about human brain metabolism using a variety of methods from brain imaging and stereology to transcriptomics. Next, we examine novel opportunities that stem cell technologies and single-cell transcriptomics provide to further our knowledge of human brain energetics. These new experimental approaches provide the ability to elucidate the functional effects of changes in genetic sequence and expression levels that potentially had a profound impact on the evolution of the human brain.
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Affiliation(s)
- Amy L Bauernfeind
- Department of Neuroscience, Washington University Medical School, St. Louis, Missouri, USA.,Department of Anthropology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Courtney C Babbitt
- Department of Biology, University of Massachusetts Amherst, Amherst, Massachusetts, USA
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22
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Hale N. Inuit metabolism revisited: what drove the selective sweep of CPT1a L479? Mol Genet Metab 2020; 129:255-271. [PMID: 32088118 DOI: 10.1016/j.ymgme.2020.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 01/30/2020] [Indexed: 12/31/2022]
Abstract
This article reassesses historical studies of Inuit metabolism in light of recent developments in evolutionary genetics. It discusses the possible selective advantage of a variant of CPT1a, which encodes the rate limiting enzyme in hepatic fatty acid oxidation. The L479 variant of CPT1a underwent one of the strongest known selective sweeps in human history and is specific to Inuit and Yu'pik populations. Recent hypotheses predict that this variant may have been selected in response to possible detrimental effects of chronic ketosis in communities with very low carbohydrate consumption. Assessing these hypotheses alongside several alternative explanations of the selective sweep, this article challenges the notion that the selection of L479 is linked to predicted detrimental effects of ketosis. Bringing together for the first time data from biochemical, metabolic, and physiological studies inside and outside the Inuit sphere, it aims to provide a broader interpretative framework and a more comprehensive way to understand the selective sweep. It suggests that L479 may have provided a selective advantage in glucose conservation as part of a metabolic adaptation to very low carbohydrate and high protein consumption, but not necessarily a ketogenic state, in an extremely cold environment. A high intake of n-3 fatty acids may be linked to selection through the mitigation of a detrimental effect of the mutation that arises in the fasted state. The implications of these conclusions for our broader understanding of very low carbohydrate metabolism, and for dietary recommendations for Inuit and non-Inuit populations, are discussed.
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23
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Beaudet A, Clarke RJ, Heaton JL, Pickering TR, Carlson KJ, Crompton RH, Jashashvili T, Bruxelles L, Jakata K, Bam L, Van Hoorebeke L, Kuman K, Stratford D. The atlas of StW 573 and the late emergence of human-like head mobility and brain metabolism. Sci Rep 2020; 10:4285. [PMID: 32179760 PMCID: PMC7075956 DOI: 10.1038/s41598-020-60837-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 02/18/2020] [Indexed: 12/24/2022] Open
Abstract
Functional morphology of the atlas reflects multiple aspects of an organism’s biology. More specifically, its shape indicates patterns of head mobility, while the size of its vascular foramina reflects blood flow to the brain. Anatomy and function of the early hominin atlas, and thus, its evolutionary history, are poorly documented because of a paucity of fossilized material. Meticulous excavation, cleaning and high-resolution micro-CT scanning of the StW 573 (‘Little Foot’) skull has revealed the most complete early hominin atlas yet found, having been cemented by breccia in its displaced and flipped over position on the cranial base anterolateral to the foramen magnum. Description and landmark-free morphometric analyses of the StW 573 atlas, along with other less complete hominin atlases from Sterkfontein (StW 679) and Hadar (AL 333-83), confirm the presence of an arboreal component in the positional repertoire of Australopithecus. Finally, assessment of the cross-sectional areas of the transverse foramina of the atlas and the left carotid canal in StW 573 further suggests there may have been lower metabolic costs for cerebral tissues in this hominin than have been attributed to extant humans and may support the idea that blood perfusion of these tissues increased over the course of hominin evolution.
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Affiliation(s)
- Amélie Beaudet
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa. .,Department of Anatomy, University of Pretoria, PO Box 2034, Pretoria, 0001, South Africa.
| | - Ronald J Clarke
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa
| | - Jason L Heaton
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa.,Department of Biology, Birmingham-Southern College, 900 Arkadelphia Road, Birmingham, AL, 35254, United States.,Plio-Pleistocene Palaeontology Section, Department of Vertebrates, Ditsong National Museum of Natural History (Transvaal Museum), 432 Paul Kruger Street, Pretoria Central, Pretoria, South Africa
| | - Travis R Pickering
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa.,Department of Biology, Birmingham-Southern College, 900 Arkadelphia Road, Birmingham, AL, 35254, United States.,Department of Anthropology, University of Wisconsin, Madison, WI, 53706, United States
| | - Kristian J Carlson
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa.,Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, 1975 Zonal Avenue, Los Angeles, CA, 90033, United States
| | - Robin H Crompton
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa.,Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, William Henry Duncan Building, W Derby Street, Liverpool, L7 8TX, United Kingdom
| | - Tea Jashashvili
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa.,Molecular Imaging Center, Department of Radiology, Keck School of Medicine, University of Southern California, 2250 Alcazar Street, Los Angeles, CA, 90033, United States.,Department of Geology and Paleontology, Georgian National Museum, 3 Shota Rustaveli Ave, T'bilisi, 0105, Georgia
| | - Laurent Bruxelles
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa.,French National Institute for Preventive Archaeological Researches (INRAP), 561 rue Etienne Lenoir, 30900, Nîmes, France.,French Institute of South Africa (IFAS), USR 3336 CNRS, 62 Juta Street, Braamfontein, Johannesburg, 2001, South Africa
| | - Kudakwashe Jakata
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa
| | - Lunga Bam
- South African Nuclear Energy Corporation SOC Ltd. (Necsa), Elias Motsoaledi Street Ext. (Church Street West), R104, Pelindaba, North West Province, South Africa
| | - Luc Van Hoorebeke
- UGCT Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86/N12, B-9000, Gent, Belgium
| | - Kathleen Kuman
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa
| | - Dominic Stratford
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS, 2050, South Africa
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24
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Royer-Carenzi M, Didier G. Testing for correlation between traits under directional evolution. J Theor Biol 2019; 482:109982. [PMID: 31446022 DOI: 10.1016/j.jtbi.2019.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 05/24/2019] [Accepted: 08/19/2019] [Indexed: 10/26/2022]
Abstract
Being confounding factors, directional trends are likely to make two quantitative traits appear as spuriously correlated. By determining the probability distributions of independent contrasts when traits evolve following Brownian motions with linear trends, we show that the standard independent contrasts can not be used to test for correlation in this situation. We propose a multiple regression approach which corrects the bias caused by directional evolution. We show that our approach is equivalent to performing a Phylogenetic Generalized Least Squares (PGLS) analysis with tip times as covariables by providing a new and more general proof of the equivalence between PGLS and independent contrasts methods. Our approach is assessed and compared with three previous correlation tests on data simulated in various situations and overall outperforms all the other methods. The approach is next illustrated on a real dataset to test for correlation between hominin cranial capacity and body mass.
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25
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Amato KR, Mallott EK, McDonald D, Dominy NJ, Goldberg T, Lambert JE, Swedell L, Metcalf JL, Gomez A, Britton GAO, Stumpf RM, Leigh SR, Knight R. Convergence of human and Old World monkey gut microbiomes demonstrates the importance of human ecology over phylogeny. Genome Biol 2019; 20:201. [PMID: 31590679 PMCID: PMC6781418 DOI: 10.1186/s13059-019-1807-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 08/29/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Comparative data from non-human primates provide insight into the processes that shaped the evolution of the human gut microbiome and highlight microbiome traits that differentiate humans from other primates. Here, in an effort to improve our understanding of the human microbiome, we compare gut microbiome composition and functional potential in 14 populations of humans from ten nations and 18 species of wild, non-human primates. RESULTS Contrary to expectations from host phylogenetics, we find that human gut microbiome composition and functional potential are more similar to those of cercopithecines, a subfamily of Old World monkey, particularly baboons, than to those of African apes. Additionally, our data reveal more inter-individual variation in gut microbiome functional potential within the human species than across other primate species, suggesting that the human gut microbiome may exhibit more plasticity in response to environmental variation compared to that of other primates. CONCLUSIONS Given similarities of ancestral human habitats and dietary strategies to those of baboons, these findings suggest that convergent ecologies shaped the gut microbiomes of both humans and cercopithecines, perhaps through environmental exposure to microbes, diet, and/or associated physiological adaptations. Increased inter-individual variation in the human microbiome may be associated with human dietary diversity or the ability of humans to inhabit novel environments. Overall, these findings show that diet, ecology, and physiological adaptations are more important than host-microbe co-diversification in shaping the human microbiome, providing a key foundation for comparative analyses of the role of the microbiome in human biology and health.
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Affiliation(s)
- Katherine R. Amato
- Department of Anthropology, Northwestern University, 1810 Hinman Ave, Evanston, IL 60208 USA
| | - Elizabeth K. Mallott
- Department of Anthropology, Northwestern University, 1810 Hinman Ave, Evanston, IL 60208 USA
| | - Daniel McDonald
- Department of Pediatrics, University of California San Diego, San Diego, 92093 USA
- Center for Microbiome Innovation, University of California San Diego, San Diego, 92093 USA
| | | | - Tony Goldberg
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, 53706 USA
| | - Joanna E. Lambert
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, 80302 USA
| | - Larissa Swedell
- Department of Anthropology, City University of New York - Queens College, New York, 11367 USA
| | - Jessica L. Metcalf
- Department of Animal Sciences, Colorado State University, Fort Collins, 80521 USA
| | - Andres Gomez
- Department of Animal Sciences, University of Minnesota, Minneapolis, 55108 USA
| | | | - Rebecca M. Stumpf
- Department of Anthropology, University of Illinois at Urbana-Champaign, Urbana, 61801 USA
| | - Steven R. Leigh
- Department of Anthropology, University of Colorado Boulder, Boulder, 80302 USA
| | - Rob Knight
- Department of Pediatrics, University of California San Diego, San Diego, 92093 USA
- Center for Microbiome Innovation, University of California San Diego, San Diego, 92093 USA
- Department of Computer Science and Engineering, University of California San Diego, San Diego, 92093 USA
- Department of Bioengineering, University of California San Diego, San Diego, 92093 USA
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26
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DeCasien AR, Higham JP. Primate mosaic brain evolution reflects selection on sensory and cognitive specialization. Nat Ecol Evol 2019; 3:1483-1493. [PMID: 31548648 DOI: 10.1038/s41559-019-0969-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 07/26/2019] [Indexed: 02/06/2023]
Abstract
The mammalian brain is composed of numerous functionally distinct structures that vary in size within and between clades, reflecting selection for sensory and cognitive specialization. Primates represent a particularly interesting case in which to examine mosaic brain evolution since they exhibit marked behavioural variation, spanning most social structures, diets and activity periods observed across mammals. Although studies have consistently demonstrated a trade-off between visual and olfactory specialization in primates, studies of some regions (for example, the neocortex) have produced conflicting results. Here, we analyse the socioecological factors influencing the relative size of 33 brain regions, using updated statistical techniques and data from more species and individuals than previous studies. Our results confirm that group-living species and those with high-quality diets have expanded olfactory or visual systems, depending on whether they are nocturnal or diurnal. Conversely, regions associated with spatial memory are expanded in solitary species and those with low-quality diets, suggesting a trade-off between visual processing and spatial memory. Contrary to previous work, we show that diet quality predicts relative neocortex size at least as well as, if not better than, social complexity. Overall, our results demonstrate that primate brain structure is largely driven by selection on sensory and cognitive specializations that develop in response to divergent socioecological niches.
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Affiliation(s)
- Alex R DeCasien
- Department of Anthropology, New York University, New York, NY, USA. .,New York Consortium in Evolutionary Primatology, New York, NY, USA.
| | - James P Higham
- Department of Anthropology, New York University, New York, NY, USA.,New York Consortium in Evolutionary Primatology, New York, NY, USA
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27
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Bordone MP, Salman MM, Titus HE, Amini E, Andersen JV, Chakraborti B, Diuba AV, Dubouskaya TG, Ehrke E, Espindola de Freitas A, Braga de Freitas G, Gonçalves RA, Gupta D, Gupta R, Ha SR, Hemming IA, Jaggar M, Jakobsen E, Kumari P, Lakkappa N, Marsh APL, Mitlöhner J, Ogawa Y, Paidi RK, Ribeiro FC, Salamian A, Saleem S, Sharma S, Silva JM, Singh S, Sulakhiya K, Tefera TW, Vafadari B, Yadav A, Yamazaki R, Seidenbecher CI. The energetic brain - A review from students to students. J Neurochem 2019; 151:139-165. [PMID: 31318452 DOI: 10.1111/jnc.14829] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 07/03/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022]
Abstract
The past 20 years have resulted in unprecedented progress in understanding brain energy metabolism and its role in health and disease. In this review, which was initiated at the 14th International Society for Neurochemistry Advanced School, we address the basic concepts of brain energy metabolism and approach the question of why the brain has high energy expenditure. Our review illustrates that the vertebrate brain has a high need for energy because of the high number of neurons and the need to maintain a delicate interplay between energy metabolism, neurotransmission, and plasticity. Disturbances to the energetic balance, to mitochondria quality control or to glia-neuron metabolic interaction may lead to brain circuit malfunction or even severe disorders of the CNS. We cover neuronal energy consumption in neural transmission and basic ('housekeeping') cellular processes. Additionally, we describe the most common (glucose) and alternative sources of energy namely glutamate, lactate, ketone bodies, and medium chain fatty acids. We discuss the multifaceted role of non-neuronal cells in the transport of energy substrates from circulation (pericytes and astrocytes) and in the supply (astrocytes and microglia) and usage of different energy fuels. Finally, we address pathological consequences of disrupted energy homeostasis in the CNS.
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Affiliation(s)
- Melina Paula Bordone
- Facultad de Farmacia y Bioquímica, Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mootaz M Salman
- Department of Cell Biology, Harvard Medical School, and Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Haley E Titus
- Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Elham Amini
- Department of Medicine, University Kebangsaan Malaysia Medical Centre (HUKM), Cheras, Kuala Lumpur, Malaysia
| | - Jens V Andersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Artem V Diuba
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Tatsiana G Dubouskaya
- Institute of Biophysics and Cell Engineering, National Academy of Sciences of Belarus, Minsk, Belarus
| | - Eric Ehrke
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany
| | - Andiara Espindola de Freitas
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, California, USA
| | | | | | | | - Richa Gupta
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Sharon R Ha
- Baylor College of Medicine, Houston, Texas, USA
| | - Isabel A Hemming
- Brain Growth and Disease Laboratory, The Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia.,School of Medicine and Pharmacology, The University of Western Australia, Crawley, Australia
| | - Minal Jaggar
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Emil Jakobsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Punita Kumari
- Defense Institute of Physiology and allied sciences, Defense Research and Development Organization, Timarpur, Delhi, India
| | - Navya Lakkappa
- Department of Pharmacology, JSS college of Pharmacy, Ooty, India
| | - Ashley P L Marsh
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Jessica Mitlöhner
- Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany
| | - Yuki Ogawa
- The Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | | | | | - Ahmad Salamian
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Suraiya Saleem
- CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Sorabh Sharma
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Joana M Silva
- Life and Health Sciences Research Institute (ICVS), Medical School, University of Minho, Braga, Portugal
| | - Shripriya Singh
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Kunjbihari Sulakhiya
- Department of Pharmacy, Indira Gandhi National Tribal University, Amarkantak, India
| | - Tesfaye Wolde Tefera
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Behnam Vafadari
- Institute of environmental medicine, UNIKA-T, Technical University of Munich, Munich, Germany
| | - Anuradha Yadav
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Reiji Yamazaki
- Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.,Center for Behavioral Brain Sciences (CBBS), Otto von Guericke University, Magdeburg, Germany
| | - Constanze I Seidenbecher
- Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany.,Center for Behavioral Brain Sciences (CBBS), Otto von Guericke University, Magdeburg, Germany
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Larbey C, Mentzer SM, Ligouis B, Wurz S, Jones MK. Cooked starchy food in hearths ca. 120 kya and 65 kya (MIS 5e and MIS 4) from Klasies River Cave, South Africa. J Hum Evol 2019; 131:210-227. [DOI: 10.1016/j.jhevol.2019.03.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/13/2019] [Accepted: 03/14/2019] [Indexed: 01/12/2023]
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Quinn RL. Isotopic equifinality and rethinking the diet of
Australopithecus anamensis. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:403-421. [DOI: 10.1002/ajpa.23846] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 03/08/2019] [Accepted: 04/16/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Rhonda L. Quinn
- Department of Sociology, Anthropology and Social WorkSeton Hall University South Orange New Jersey
- Department of Earth and Planetary SciencesRutgers University Piscataway New Jersey
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30
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Multiple Components of Phylogenetic Non-stationarity in the Evolution of Brain Size in Fossil Hominins. Evol Biol 2019. [DOI: 10.1007/s11692-019-09471-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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31
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Understanding Human Physiological Limitations and Societal Pressures in Favor of Overeating Helps to Avoid Obesity. Nutrients 2019; 11:nu11020227. [PMID: 30678194 PMCID: PMC6412691 DOI: 10.3390/nu11020227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 01/10/2019] [Accepted: 01/11/2019] [Indexed: 12/27/2022] Open
Abstract
Fat gain in our United States (US) environment of over-abundant, convenient, and palatable food is associated with hypertension, cardiovascular disease, diabetes, and increased mortality. Fuller understanding of physiological and environmental challenges to healthy weight maintenance could help prevent these morbidities. Human physiological limitations that permit development of obesity include a predilection to overeat palatable diets, inability to directly detect energy eaten or expended, a large capacity for fat storage, and the difficulty of losing body fat. Innate defenses resisting fat loss include reduced resting metabolism, increased hunger, and high insulin sensitivity, promoting a regain of fat, glycogen, and lean mass. Environmental challenges include readily available and heavily advertised palatable foods, policies and practices that make them abundant, less-than-ideal recommendations regarding national dietary macronutrient intake, and a frequently sedentary lifestyle. After gaining excess fat, some metabolic burdens can be mitigated though thoughtful selection of nutrients. Reduced dietary salt helps lower hypertension, less dietary sugar lowers risk of cardiovascular disease and obesity, and reducing proportion of dietary carbohydrates lowers post-meal insulin secretion and insulin resistance. Food intake and exercise should also be considered thoughtfully, as exercise in a fasted state and before the meals raises glucose intolerance, while exercising shortly after eating lowers it. In summary, we cannot directly detect energy eaten or expended, we have a genetic predisposition to eat palatable diets even when not hungry, and we have a large capacity for fat storage and a difficult time permanently losing excess fat. Understanding this empowers individuals to avoid overeating and helps them avoid obesity.
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33
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Epigenetic Erosion in Adult Stem Cells: Drivers and Passengers of Aging. Cells 2018; 7:cells7120237. [PMID: 30501028 PMCID: PMC6316114 DOI: 10.3390/cells7120237] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 11/22/2018] [Accepted: 11/26/2018] [Indexed: 02/06/2023] Open
Abstract
In complex organisms, stem cells are key for tissue maintenance and regeneration. Adult stem cells replenish continuously dividing tissues of the epithelial and connective types, whereas in non-growing muscle and nervous tissues, they are mainly activated upon injury or stress. In addition to replacing deteriorated cells, adult stem cells have to prevent their exhaustion by self-renewal. There is mounting evidence that both differentiation and self-renewal are impaired upon aging, leading to tissue degeneration and functional decline. Understanding the molecular pathways that become deregulate in old stem cells is crucial to counteract aging-associated tissue impairment. In this review, we focus on the epigenetic mechanisms governing the transition between quiescent and active states, as well as the decision between self-renewal and differentiation in three different stem cell types, i.e., spermatogonial stem cells, hematopoietic stem cells, and muscle stem cells. We discuss the epigenetic events that channel stem cell fate decisions, how this epigenetic regulation is altered with age, and how this can lead to tissue dysfunction and disease. Finally, we provide short prospects of strategies to preserve stem cell function and thus promote healthy aging.
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34
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Bailey DM. Oxygen, evolution and redox signalling in the human brain; quantum in the quotidian. J Physiol 2018; 597:15-28. [PMID: 30315729 DOI: 10.1113/jp276814] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 09/27/2018] [Indexed: 12/20/2022] Open
Abstract
Rising atmospheric oxygen (O2 ) levels provided a selective pressure for the evolution of O2 -dependent micro-organisms that began with the autotrophic eukaryotes. Since these primordial times, the respiring mammalian cell has become entirely dependent on the constancy of electron flow, with molecular O2 serving as the terminal electron acceptor in mitochondrial oxidative phosphorylation. Indeed, the ability to 'sense' O2 and maintain homeostasis is considered one of the most important roles of the central nervous system (CNS) and probably represented a major driving force in the evolution of the human brain. Today, modern humans have evolved with an oversized brain committed to a continually active state and, as a consequence, paradoxically vulnerable to failure if the O2 supply is interrupted. However, our pre-occupation with O2 , the elixir of life, obscures the fact that it is a gas with a Janus face, capable of sustaining life in physiologically controlled amounts yet paradoxically deadly to the CNS when in excess. A closer look at its quantum structure reveals precisely why; the triplet ground state diatomic O2 molecule is paramagnetic and exists in air as a free radical, constrained from reacting aggressively with the brain's organic molecules due to its 'spin restriction', a thermodynamic quirk of evolutionary fate. By further exploring O2 's free radical 'quantum quirkiness', including emergent (quantum) physiological phenomena, our understanding of precisely how the human brain senses O2 deprivation (hypoxia) and the elaborate redox-signalling defence mechanisms that defend O2 homeostasis has the potential to offer unique insights into the pathophysiology and treatment of human brain disease.
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Affiliation(s)
- Damian Miles Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Wales, UK
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35
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Bailey DM. RETRACTED ARTICLE: The quantum physiology of oxygen; from electrons to the evolution of redox signaling in the human brain. Bioelectron Med 2018; 4:13. [PMID: 32232089 PMCID: PMC7098224 DOI: 10.1186/s42234-018-0014-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 09/19/2018] [Indexed: 12/11/2022] Open
Abstract
Rising atmospheric oxygen (O2) levels provided a selective pressure for the evolution of O2-dependent micro-organisms that began with the autotrophic eukaryotes. Since these primordial times, the respiring mammalian cell has become entirely dependent on the constancy of electron flow with molecular O2 serving as the terminal electron acceptor in mitochondrial oxidative phosphorylation. Indeed, the ability to “sense” O2 and maintain homeostasis is considered one of the most important roles of the central nervous system (CNS) and likely represented a major driving force in the evolution of the human brain. Today, modern humans have evolved with an oversized brain committed to a continually active state and as a consequence, paradoxically vulnerable to failure if the O2 supply is interrupted. However, our pre-occupation with O2, the elixir of life, obscures the fact that it is a gas with a Janus Face, capable of sustaining life in physiologically controlled amounts yet paradoxically deadly to the CNS when in excess. A closer look at its quantum structure reveals precisely why; the triplet ground state diatomic O2 molecule is paramagnetic and exists in air as a free radical, constrained from reacting aggressively with the brain’s organic molecules due to its “spin restriction”, a thermodynamic quirk of evolutionary fate. By further exploring O2’s free radical “quantum quirkiness” including emergent quantum physiological phenomena, our understanding of precisely how the human brain senses O2 deprivation (hypoxia) and the elaborate redox-signaling defense mechanisms that defend O2 homeostasis has the potential to offer unique insights into the pathophysiology and treatment of human brain disease.
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Affiliation(s)
- Damian Miles Bailey
- Neurovascular Research Laboratory, Alfred Russel Wallace Building, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT UK
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36
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Hawkes K, Finlay BL. Mammalian brain development and our grandmothering life history. Physiol Behav 2018; 193:55-68. [DOI: 10.1016/j.physbeh.2018.01.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 01/15/2018] [Accepted: 01/16/2018] [Indexed: 11/28/2022]
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37
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Simmen B, Pasquet P, Masi S, Koppert GJA, Wells JCK, Hladik CM. Primate energy input and the evolutionary transition to energy-dense diets in humans. Proc Biol Sci 2018; 284:rspb.2017.0577. [PMID: 28592672 DOI: 10.1098/rspb.2017.0577] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 05/08/2017] [Indexed: 01/08/2023] Open
Abstract
Humans and other large-brained hominins have been proposed to increase energy turnover during their evolutionary history. Such increased energy turnover is plausible, given the evolution of energy-rich diets, but requires empirical confirmation. Framing human energetics in a phylogenetic context, our meta-analysis of 17 wild non-human primate species shows that daily metabolizable energy input follows an allometric relationship with body mass where the allometric exponent for mass is 0.75 ± 0.04, close to that reported for daily energy expenditure measured with doubly labelled water in primates. Human populations at subsistence level (n = 6) largely fall within the variation of primate species in the scaling of energy intake and therefore do not consume significantly more energy than predicted for a non-human primate of equivalent mass. By contrast, humans ingest a conspicuously lower mass of food (-64 ± 6%) compared with primates and maintain their energy intake relatively more constantly across the year. We conclude that our hominin hunter-gatherer ancestors did not increase their energy turnover beyond the allometric relationship characterizing all primate species. The reduction in digestive costs due to consumption of a lower mass of high-quality food, as well as stabilization of energy supply, may have been important evolutionary steps enabling encephalization in the absence of significantly raised energy intakes.
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Affiliation(s)
- Bruno Simmen
- Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, UMR 7206-Eco-anthropologie et Ethnobiologie, 1 Avenue du Petit Château, 91800 Brunoy, France
| | - Patrick Pasquet
- Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, Musée de l'Homme, UMR 7206-Eco-anthropologie et Ethnologie, 17 Place du Trocadéro, 75116 Paris, France
| | - Shelly Masi
- Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, Musée de l'Homme, UMR 7206-Eco-anthropologie et Ethnologie, 17 Place du Trocadéro, 75116 Paris, France
| | - Georgius J A Koppert
- Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, UMR 7206-Eco-anthropologie et Ethnobiologie, 1 Avenue du Petit Château, 91800 Brunoy, France
| | - Jonathan C K Wells
- Childhood Nutrition Research Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK
| | - Claude Marcel Hladik
- Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, UMR 7206-Eco-anthropologie et Ethnobiologie, 1 Avenue du Petit Château, 91800 Brunoy, France
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38
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Boyer DM, Harrington AR. Scaling of bony canals for encephalic vessels in euarchontans: Implications for the role of the vertebral artery and brain metabolism. J Hum Evol 2017; 114:85-101. [PMID: 29447763 DOI: 10.1016/j.jhevol.2017.09.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 09/01/2017] [Accepted: 09/02/2017] [Indexed: 01/07/2023]
Abstract
Supplying the central nervous system with oxygen and glucose for metabolic activities is a critical function for all animals at physiologic, anatomical, and behavioral levels. A relatively proximate challenge to nourishing the brain is maintaining adequate blood flow. Euarchontans (primates, dermopterans and treeshrews) display a diversity of solutions to this challenge. Although the vertebral artery is a major encephalic vessel, previous research has questioned its importance for irrigating the cerebrum. This presents a puzzling scenario for certain strepsirrhine primates (non-cheirogaleid lemuriforms) that have reduced promontorial branches of the internal carotid artery and no apparent alternative encephalic vascular route except for the vertebral artery. Here, we present results of phylogenetic comparative analyses of data on the cross-sectional area of bony canals that transmit the vertebral artery (transverse foramina). These results show that, across primates (and within major primate subgroups), variation in the transverse foramina helps significantly to explain variation in forebrain mass even when variation in promontorial canal cross-sectional areas are also considered. Furthermore, non-cheirogaleid lemuriforms have larger transverse foramina for their endocranial volume than other euarchontans, suggesting that the vertebral arteries compensate for reduced promontorial artery size. We also find that, among internal carotid-reliant euarchontans, species that are more encephalized tend to have a promontorial canal that is larger relative to the transverse foramina. Tentatively, we consider the correlation between arterial canal diameters (as a proxy for blood flow) and brain metabolic demands. The results of this analysis imply that human investment in brain metabolism (∼27% of basal metabolic rate) may not be exceptional among euarchontans.
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Affiliation(s)
- Doug M Boyer
- Department of Evolutionary Anthropology, Duke University, Durham, NC, 27708, USA.
| | - Arianna R Harrington
- Department of Evolutionary Anthropology, Duke University, Durham, NC, 27708, USA
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39
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Said-Mohamed R, Pettifor JM, Norris SA. Life History theory hypotheses on child growth: Potential implications for short and long-term child growth, development and health. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 165:4-19. [PMID: 29072305 DOI: 10.1002/ajpa.23340] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 09/27/2017] [Accepted: 10/01/2017] [Indexed: 12/12/2022]
Abstract
Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms' strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade-off between linear growth and brain growth. Undernutrition in infancy and childhood may trigger adaptive physiological mechanisms prioritizing the brain at the expense of body growth. Another hypothesis is that the period from conception to infancy is a critical window of developmental plasticity of linear growth, the duration of which may vary between and within populations. The transition from infancy to childhood may mark the end of a critical window of opportunity for improving child growth. Both hypotheses emphasize the developmental plasticity of linear growth and the potential determinants of growth variability (including the role of parent-offspring conflict in maternal resources allocation). Implications of these hypotheses in populations with high burdens of undernutrition and infections are discussed. In South Africa, HIV/AIDS during pregnancy (associated with adverse birth outcomes, short duration of breastfeeding, and social consequences) may lead to a shortened window of developmental plasticity of growth. Furthermore, undernutrition and infectious diseases in children living in South Africa, a country undergoing a rapid nutrition transition, may have adverse consequences on individuals' cognitive abilities and risks of cardio-metabolic diseases. Studies are needed to identify physiological mechanisms underlying energy allocation between biological functions and their potential impacts on health.
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Affiliation(s)
- Rihlat Said-Mohamed
- Department of Paediatrics and Child Health, MRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Gauteng 2193, South Africa
| | - John M Pettifor
- Department of Paediatrics and Child Health, MRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Gauteng 2193, South Africa
| | - Shane A Norris
- Department of Paediatrics and Child Health, MRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Gauteng 2193, South Africa
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40
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Longman D, Stock JT, Wells JCK. A trade-off between cognitive and physical performance, with relative preservation of brain function. Sci Rep 2017; 7:13709. [PMID: 29057922 PMCID: PMC5651807 DOI: 10.1038/s41598-017-14186-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/19/2017] [Indexed: 01/08/2023] Open
Abstract
Debate surrounds the issue of how the large, metabolically expensive brains of Homo sapiens can be energetically afforded. At the evolutionary level, decreased investment in muscularity, adiposity and the digestive tract allow for a larger brain. Developmentally, high neo-natal adiposity and preferential distribution of resources to the brain provide an energetic buffer during times of environmental stress. Through an experimental design, we investigated the hypothesis of a trade-off involving brain and muscle at the acute level in humans. Mental performance was measured by a free-recall test, and physical performance by power output on an indoor rowing ergometer. Sixty-two male student rowers performed the two tests in isolation, and then again simultaneously. Paired samples t-tests revealed that both power output and mental performance reduced when tested together compared to in isolation (t(61) = 9.699, p < 0.001 and t(61) = 8.975, p < 0.001). Furthermore, the decrease in physical performance was greater than the decrease in mental performance (t(61) = -2.069, p = 0.043). This is the first investigation to demonstrate an acute level trade-off between these two functions, and provides support for the selfish brain hypothesis due to the relative preservation of cognitive function over physical power output. The underlying mechanism is unclear, and requires further work.
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Affiliation(s)
- Daniel Longman
- Department of Archaeology and Anthropology, University of Cambridge, Cambridge, CB2 3QG, UK.
| | - Jay T Stock
- Department of Archaeology and Anthropology, University of Cambridge, Cambridge, CB2 3QG, UK
- Department of Anthropology, University of Western Ontario, Ontario, Canada
| | - Jonathan C K Wells
- Childhood Nutrition Research Centre, UCL Institute of Child Health, London, WC1N 1EH, UK
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41
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Locomotion and basicranial anatomy in primates and marsupials. J Hum Evol 2017; 111:163-178. [DOI: 10.1016/j.jhevol.2017.07.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 06/27/2017] [Accepted: 07/07/2017] [Indexed: 01/19/2023]
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42
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León-Del-Río A, Valadez-Graham V, Gravel RA. Holocarboxylase Synthetase: A Moonlighting Transcriptional Coregulator of Gene Expression and a Cytosolic Regulator of Biotin Utilization. Annu Rev Nutr 2017; 37:207-223. [DOI: 10.1146/annurev-nutr-042617-104653] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Alfonso León-Del-Río
- Programa de Investigación de Cáncer de Mama y Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de Mexico 04500, México
| | - Viviana Valadez-Graham
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62250, México
| | - Roy A. Gravel
- Department of Biochemistry & Molecular Biology, the University of Calgary and the Alberta Children's Hospital Research Institute for Child and Maternal Health, Calgary, Alberta T2N 4N1, Canada
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Okerblom J, Varki A. Biochemical, Cellular, Physiological, and Pathological Consequences of Human Loss of N-Glycolylneuraminic Acid. Chembiochem 2017; 18:1155-1171. [PMID: 28423240 DOI: 10.1002/cbic.201700077] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Indexed: 12/15/2022]
Abstract
About 2-3 million years ago, Alu-mediated deletion of a critical exon in the CMAH gene became fixed in the hominin lineage ancestral to humans, possibly through a stepwise process of selection by pathogen targeting of the CMAH product (the sialic acid Neu5Gc), followed by reproductive isolation through female anti-Neu5Gc antibodies. Loss of CMAH has occurred independently in some other lineages, but is functionally intact in Old World primates, including our closest relatives, the chimpanzee. Although the biophysical and biochemical ramifications of losing tens of millions of Neu5Gc hydroxy groups at most cell surfaces remains poorly understood, we do know that there are multiscale effects functionally relevant to both sides of the host-pathogen interface. Hominin CMAH loss might also contribute to understanding human evolution, at the time when our ancestors were starting to use stone tools, increasing their consumption of meat, and possibly hunting. Comparisons with chimpanzees within ethical and practical limitations have revealed some consequences of human CMAH loss, but more has been learned by using a mouse model with a human-like Cmah inactivation. For example, such mice can develop antibodies against Neu5Gc that could affect inflammatory processes like cancer progression in the face of Neu5Gc metabolic incorporation from red meats, display a hyper-reactive immune system, a human-like tendency for delayed wound healing, late-onset hearing loss, insulin resistance, susceptibility to muscular dystrophy pathologies, and increased sensitivity to multiple human-adapted pathogens involving sialic acids. Further studies in such mice could provide a model for other human-specific processes and pathologies involving sialic acid biology that have yet to be explored.
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Affiliation(s)
- Jonathan Okerblom
- Biomedical Sciences Graduate Program, University of California in San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0687, USA
| | - Ajit Varki
- Glycobiology Research and Training Center, GRTC) and, Center for Academic Research and Training in Anthropogeny, CARTA), Departments of Medicine and Cellular and Molecular Medicine, University of California in San Diego, La Jolla, CA, 92093-0687, USA
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44
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Babbitt CC, Haygood R, Nielsen WJ, Wray GA. Gene expression and adaptive noncoding changes during human evolution. BMC Genomics 2017; 18:435. [PMID: 28583075 PMCID: PMC5460488 DOI: 10.1186/s12864-017-3831-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/31/2017] [Indexed: 01/14/2023] Open
Abstract
Background Despite evidence for adaptive changes in both gene expression and non-protein-coding, putatively regulatory regions of the genome during human evolution, the relationship between gene expression and adaptive changes in cis-regulatory regions remains unclear. Results Here we present new measurements of gene expression in five tissues of humans and chimpanzees, and use them to assess this relationship. We then compare our results with previous studies of adaptive noncoding changes, analyzing correlations at the level of gene ontology groups, in order to gain statistical power to detect correlations. Conclusions Consistent with previous studies, we find little correlation between gene expression and adaptive noncoding changes at the level of individual genes; however, we do find significant correlations at the level of biological function ontology groups. The types of function include processes regulated by specific transcription factors, responses to genetic or chemical perturbations, and differentiation of cell types within the immune system. Among functional categories co-enriched with both differential expression and noncoding adaptation, prominent themes include cancer, particularly epithelial cancers, and neural development and function. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3831-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Courtney C Babbitt
- Department of Biology, Duke University, Durham, NC, 27708, USA. .,Institute for Genome Sciences & Policy, Duke University, Durham, NC, 27708, USA. .,Present Address: Department of Biology, University of Massachusetts Amherst, Amherst, MA, 01003, USA.
| | | | | | - Gregory A Wray
- Department of Biology, Duke University, Durham, NC, 27708, USA.,Institute for Genome Sciences & Policy, Duke University, Durham, NC, 27708, USA.,Department of Evolutionary Anthropology, Duke University, Durham, NC, 27708, USA
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Wells JCK. Body composition and susceptibility to type 2 diabetes: an evolutionary perspective. Eur J Clin Nutr 2017; 71:881-889. [PMID: 28352118 DOI: 10.1038/ejcn.2017.31] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 01/27/2017] [Accepted: 01/31/2017] [Indexed: 12/13/2022]
Abstract
Type 2 diabetes is rapidly increasing in prevalence worldwide, in concert with epidemics of obesity and sedentary behavior that are themselves tracking economic development. Within this broad pattern, susceptibility to diabetes varies substantially in association with ethnicity and nutritional exposures through the life-course. An evolutionary perspective may help understand why humans are so prone to this condition in modern environments, and why this risk is unequally distributed. A simple conceptual model treats diabetes risk as the function of two interacting traits, namely 'metabolic capacity' which promotes glucose homeostasis, and 'metabolic load' which challenges glucose homoeostasis. This conceptual model helps understand how long-term and more recent trends in body composition can be considered to have shaped variability in diabetes risk. Hominin evolution appears to have continued a broader trend evident in primates, towards lower levels of muscularity. In addition, hominins developed higher levels of body fatness, especially in females in relative terms. These traits most likely evolved as part of a broader reorganization of human life history traits in response to growing levels of ecological instability, enabling both survival during tough periods and reproduction during bountiful periods. Since the emergence of Homo sapiens, populations have diverged in body composition in association with geographical setting and local ecological stresses. These long-term trends in both metabolic capacity and adiposity help explain the overall susceptibility of humans to diabetes in ways that are similar to, and exacerbated by, the effects of nutritional exposures during the life-course.
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Affiliation(s)
- J C K Wells
- Childhood Nutrition Research Centre, UCL Great Ormond Street Institute of Child Health, London, UK
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Seymour RS, Bosiocic V, Snelling EP. Fossil skulls reveal that blood flow rate to the brain increased faster than brain volume during human evolution. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160305. [PMID: 27853608 PMCID: PMC5108958 DOI: 10.1098/rsos.160305] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 07/29/2016] [Indexed: 05/12/2023]
Abstract
The evolution of human cognition has been inferred from anthropological discoveries and estimates of brain size from fossil skulls. A more direct measure of cognition would be cerebral metabolic rate, which is proportional to cerebral blood flow rate (perfusion). The hominin cerebrum is supplied almost exclusively by the internal carotid arteries. The sizes of the foramina that transmitted these vessels in life can be measured in hominin fossil skulls and used to calculate cerebral perfusion rate. Perfusion in 11 species of hominin ancestors, from Australopithecus to archaic Homo sapiens, increases disproportionately when scaled against brain volume (the allometric exponent is 1.41). The high exponent indicates an increase in the metabolic intensity of cerebral tissue in later Homo species, rather than remaining constant (1.0) as expected by a linear increase in neuron number, or decreasing according to Kleiber's Law (0.75). During 3 Myr of hominin evolution, cerebral tissue perfusion increased 1.7-fold, which, when multiplied by a 3.5-fold increase in brain size, indicates a 6.0-fold increase in total cerebral blood flow rate. This is probably associated with increased interneuron connectivity, synaptic activity and cognitive function, which all ultimately depend on cerebral metabolic rate.
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Affiliation(s)
- Roger S. Seymour
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
- Author for correspondence: Roger S. Seymour e-mail:
| | - Vanya Bosiocic
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Edward P. Snelling
- Brain Function Research Group, School of Physiology, University of the Witwatersrand, Johannesburg, Gauteng 2193, South Africa
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47
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Zamora TG, Guiang SF, Georgieff MK, Widness JA. Iron is prioritized to red blood cells over the brain in phlebotomized anemic newborn lambs. Pediatr Res 2016; 79:922-8. [PMID: 26866907 PMCID: PMC4899227 DOI: 10.1038/pr.2016.20] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 12/03/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND Critically ill preterm and term neonates are at high risk for negative iron balance due to phlebotomy that occurs with frequent laboratory monitoring, and the high iron demand of rapid growth. Understanding the prioritization of iron between red blood cells (RBCs) and brain is important given iron's role in neurodevelopment. METHODS Ten neonatal twin lamb pairs (n = 20) underwent regular phlebotomy for 11 d. Lambs were randomized to receive no iron or i.v. daily iron supplementation from 1 to 5 mg/kg. Serum hemoglobin concentration and reticulocyte count were assayed, iron balance calculated, and iron content of RBCs, liver, brain, muscle, and heart measured at autopsy. RESULTS Among phlebotomized lambs: (i) liver iron concentration was directly related to net iron balance (r = 0.87; P < 0.001) and (ii) brain iron concentration was reduced as a function of net iron balance (r = 0.63) only after liver iron was depleted. In animals with negative iron balance, total RBC iron was maintained while brain iron concentration decreased as a percentage of the iron present in RBCs (r = -0.70; P < 0.01) and as a function of reticulocyte count (r = -0.63; P < 0.05). CONCLUSION Phlebotomy-induced negative iron balance limits iron availability to the developing brain.
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Affiliation(s)
- Tara G Zamora
- Children’s Hospitals and Clinics of Minnesota. St. Paul, MN, USA,Department of Pediatrics, University of Minnesota School of Medicine. Minneapolis, MN, USA,Corresponding Author Contact: Tara G Zamora, MD, 347 N Smith Ave Suite 505 St. Paul MN 55102, P: 651-220-6264 F: 651-220-7777,
| | - Sixto F Guiang
- Department of Pediatrics, University of Minnesota School of Medicine. Minneapolis, MN, USA
| | - Michael K Georgieff
- Department of Pediatrics, University of Minnesota School of Medicine. Minneapolis, MN, USA
| | - John A Widness
- Department of Pediatrics, University of Iowa School of Medicine. Iowa City, Iowa, USA
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48
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Naya DE, Naya H, Lessa EP. Brain size and thermoregulation during the evolution of the genus Homo. Comp Biochem Physiol A Mol Integr Physiol 2016; 191:66-73. [DOI: 10.1016/j.cbpa.2015.09.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 08/18/2015] [Accepted: 09/24/2015] [Indexed: 11/16/2022]
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Lake NJ, Compton AG, Rahman S, Thorburn DR. Leigh syndrome: One disorder, more than 75 monogenic causes. Ann Neurol 2015; 79:190-203. [PMID: 26506407 DOI: 10.1002/ana.24551] [Citation(s) in RCA: 317] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 10/16/2015] [Accepted: 10/18/2015] [Indexed: 12/19/2022]
Abstract
Leigh syndrome is the most common pediatric presentation of mitochondrial disease. This neurodegenerative disorder is genetically heterogeneous, and to date pathogenic mutations in >75 genes have been identified, encoded by 2 genomes (mitochondrial and nuclear). More than one-third of these disease genes have been characterized in the past 5 years alone, reflecting the significant advances made in understanding its etiological basis. We review the diverse biochemical and genetic etiology of Leigh syndrome and associated clinical, neuroradiological, and metabolic features that can provide clues for diagnosis. We discuss the emergence of genotype-phenotype correlations, insights gleaned into the molecular basis of disease, and available therapeutic options.
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Affiliation(s)
- Nicole J Lake
- Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Alison G Compton
- Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Shamima Rahman
- Mitochondrial Research Group, Genetics and Genomic Medicine, Institute of Child Health, University College London and Metabolic Unit, Great Ormond Street Hospital, London, United Kingdom
| | - David R Thorburn
- Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.,Victorian Clinical Genetic Services, Royal Children's Hospital, Melbourne, Victoria, Australia
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50
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Amato KR, Yeoman CJ, Cerda G, Schmitt CA, Cramer JD, Miller MEB, Gomez A, Turner TR, Wilson BA, Stumpf RM, Nelson KE, White BA, Knight R, Leigh SR. Variable responses of human and non-human primate gut microbiomes to a Western diet. MICROBIOME 2015; 3:53. [PMID: 26568112 PMCID: PMC4645477 DOI: 10.1186/s40168-015-0120-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 09/29/2015] [Indexed: 05/28/2023]
Abstract
BACKGROUND The human gut microbiota interacts closely with human diet and physiology. To better understand the mechanisms behind this relationship, gut microbiome research relies on complementing human studies with manipulations of animal models, including non-human primates. However, due to unique aspects of human diet and physiology, it is likely that host-gut microbe interactions operate differently in humans and non-human primates. RESULTS Here, we show that the human microbiome reacts differently to a high-protein, high-fat Western diet than that of a model primate, the African green monkey, or vervet (Chlorocebus aethiops sabaeus). Specifically, humans exhibit increased relative abundance of Firmicutes and reduced relative abundance of Prevotella on a Western diet while vervets show the opposite pattern. Predictive metagenomics demonstrate an increased relative abundance of genes associated with carbohydrate metabolism in the microbiome of only humans consuming a Western diet. CONCLUSIONS These results suggest that the human gut microbiota has unique properties that are a result of changes in human diet and physiology across evolution or that may have contributed to the evolution of human physiology. Therefore, the role of animal models for understanding the relationship between the human gut microbiota and host metabolism must be re-focused.
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Affiliation(s)
- Katherine R Amato
- Department of Anthropology, Northwestern University, Evanston, USA.
- Department of Anthropology, University of Colorado Boulder, Boulder, USA.
- BioFrontiers Institute, University of Colorado Boulder, Boulder, USA.
| | - Carl J Yeoman
- Department of Range Sciences, Montana State University, Bozeman, USA.
| | - Gabriela Cerda
- Department of Anthropology, University of Illinois, Urbana, USA.
| | - Christopher A Schmitt
- Department of Anthropology, Boston University, Boston, USA.
- Center for Neurobehavioral Genetics, University of California, Los Angeles, CA, USA.
| | - Jennifer Danzy Cramer
- Department of Sociology, Anthropology, and Women's Studies, American Military University and American Public University, Charles Town, USA.
| | | | - Andres Gomez
- The Institute for Genomic Biology, University of Illinois, Urbana, IL, 61801, USA.
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Minneapolis, USA.
| | - Trudy R Turner
- Department of Anthropology, University of Wisconsin, Milwaukee, USA.
- Department of Genetics, University of the Free State, Bloemfontein, South Africa.
| | - Brenda A Wilson
- The Institute for Genomic Biology, University of Illinois, Urbana, IL, 61801, USA.
- Department of Microbiology, University of Illinois, Urbana, USA.
| | - Rebecca M Stumpf
- Department of Anthropology, University of Illinois, Urbana, USA.
- The Institute for Genomic Biology, University of Illinois, Urbana, IL, 61801, USA.
| | | | - Bryan A White
- The Institute for Genomic Biology, University of Illinois, Urbana, IL, 61801, USA.
- Department of Animal Sciences, University of Illinois, Urbana, USA.
| | - Rob Knight
- School of Medicine, University of California San Diego, La Jolla, USA.
| | - Steven R Leigh
- Department of Anthropology, University of Colorado Boulder, Boulder, USA.
- The Institute for Genomic Biology, University of Illinois, Urbana, IL, 61801, USA.
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