Caffeine Ingestion Reverses the Circadian Rhythm Effects on Neuromuscular Performance in Highly Resistance-Trained Men

Purpose: To investigate whether caffeine ingestion counteracts the morning reduction in neuromuscular performance associated with the circadian rhythm pattern. Methods: Twelve highly resistance-trained men underwent a battery of neuromuscular tests under three different conditions; i) morning (10:00 a.m.) with caffeine ingestion (i.e., 3 mg kg 21; AMCAFF trial); ii) morning (10:00 a.m.) with placebo ingestion (AMPLAC trial); and iii) afternoon (18:00 p.m.) with placebo ingestion (PMPLAC trial). A randomized, doubleblind, crossover, placebo controlled experimental design was used, with all subjects serving as their own controls. The neuromuscular test battery consisted in the measurement of bar displacement velocity during free-weight full-squat (SQ) and bench press (BP) exercises against loads that elicit maximum strength (75 % 1RM load) and muscle power adaptations (1 m s 21 load). Isometric maximum voluntary contraction (MVCLEG) and isometric electrically evoked strength of the right knee (EVOK LEG) were measured to identify caffeine’s action mechanisms. Steroid hormone levels (serum testosterone, cortisol and growth hormone) were evaluated at the beginning of each trial (PRE). In addition, plasma norepinephrine (NE) and epinephrine were measured PRE and at the end of each trial following a standardized intense (85 % 1RM) 6 repetitions bout of SQ (POST). Results: In the PM PLAC trial, dynamic muscle strength and power output were significantly enhanced compared with AM PLA

Botanical collections as an opportunity to explore nature through the time: An untargeted metabolomic study in historical and modern Nicotiana leaves

Living and dried specimens in botanical collections play an important role in society for scientific purposes, offering the opportunity to obtain both macroscopic and molecular information for individual plants, ecosystems, and environmental studies. Untargeted metabolomics is an analytical approach that permits the simultaneous study of multiple small molecules present in an organism, which allows us to statistically compare different conditions of interest. Metabolomic approaches have been used on living specimens in botanical collections, but until now, not on historical dried material. Using the Nicotiana genus herbaceous plant (tobacco) as a case study, we propose an untargeted metabolomic study to evaluate the potential of dried historical specimens as a source of metabolomic information for the past. The metabolomic profile from polar and less-polar/apolar aqueous extracts of four modern handmade tobacco cigars (split into wrapper, binder, and filler leaves), and a set of eight late-19th to early-20th century tobacco specimens (seven tobacco leaves and one snuff powder) from the collection of the Royal Botanical Gardens at Kew (London, UK) were analysed by liquid chromatography coupled to high resolution mass spectrometry. Results showed that a wide range of polar and less-polar/apolar molecules are preserved in dried botanical material providing information optimal for metabolomic studies. The metabolomic profiles of historical dried samples were distinct enough to classify as Nicotiana tabacum or Nicotiana rustica, and showed differences based on geographic provenance or transformation/processing. Statistical models based on the molecular data from the historical material permitted us to validate the labelling of the historical collection, which identified one possible mislabelled specimen and offered some clues as to the species of one unknown Nicotiana sample. Finally, metabolomic differences in profiles between Nicotiana tabacum and modern cigars showed that both share a large proportion of their metabolomic profile, where molecular differences could be possibly associated with both location of growth and/or anthropogenic transformation of the plant in the last two centuries. This study demonstrates that dry botanical collections are a feasible source of information, and, if applied to a large set of individuals, conclusions may be drawn about the possible evolution and anthropogenic modification over time in plant material. The results are significant for disciplines interested in the history of plants, such as botany, history and archaeology.</p

Botanical collections as an opportunity to explore nature through the time: An untargeted metabolomic study in historical and modern Nicotiana leaves

Living and dried specimens in botanical collections play an important role in society for scientific purposes, offering the opportunity to obtain both macroscopic and molecular information for individual plants, ecosystems, and environmental studies. Untargeted metabolomics is an analytical approach that permits the simultaneous study of multiple small molecules present in an organism, which allows us to statistically compare different conditions of interest. Metabolomic approaches have been used on living specimens in botanical collections, but until now, not on historical dried material. Using the Nicotiana genus herbaceous plant (tobacco) as a case study, we propose an untargeted metabolomic study to evaluate the potential of dried historical specimens as a source of metabolomic information for the past. The metabolomic profile from polar and less-polar/apolar aqueous extracts of four modern handmade tobacco cigars (split into wrapper, binder, and filler leaves), and a set of eight late-19th to early-20th century tobacco specimens (seven tobacco leaves and one snuff powder) from the collection of the Royal Botanical Gardens at Kew (London, UK) were analysed by liquid chromatography coupled to high resolution mass spectrometry. Results showed that a wide range of polar and less-polar/apolar molecules are preserved in dried botanical material providing information optimal for metabolomic studies. The metabolomic profiles of historical dried samples were distinct enough to classify as Nicotiana tabacum or Nicotiana rustica, and showed differences based on geographic provenance or transformation/processing. Statistical models based on the molecular data from the historical material permitted us to validate the labelling of the historical collection, which identified one possible mislabelled specimen and offered some clues as to the species of one unknown Nicotiana sample. Finally, metabolomic differences in profiles between Nicotiana tabacum and modern cigars showed that both share a large proportion of their metabolomic profile, where molecular differences could be possibly associated with both location of growth and/or anthropogenic transformation of the plant in the last two centuries. This study demonstrates that dry botanical collections are a feasible source of information, and, if applied to a large set of individuals, conclusions may be drawn about the possible evolution and anthropogenic modification over time in plant material. The results are significant for disciplines interested in the history of plants, such as botany, history and archaeology.</p

Metabolomics in archaeological science: A review of their advances and present requirements

Metabolomics, the study of metabolites (small molecules of <1500 daltons), has been posited as a potential tool to explore the past in a comparable manner to other omics, e.g., genomics or proteomics. Archaeologists have used metabolomic approaches for a decade or so, mainly applied to organic residues adhering to archaeological materials. Because of advances in sensitivity, resolution, and the increased availability of different analytical platforms, combined with the low mass/volume required for analysis, metabolomics is now becoming a more feasible choice in the archaeological sector. Additional approaches, as presented by our group, show the versatility of metabolomics as a source of knowledge about the human past when using human osteoarchaeological remains. There is tremendous potential for metabolomics within archaeology, but further efforts are required to position it as a routine technique.</p

Metabolomics in archaeological science: A review of their advances and present requirements

Metabolomics, the study of metabolites (small molecules of <1500 daltons), has been posited as a potential tool to explore the past in a comparable manner to other omics, e.g., genomics or proteomics. Archaeologists have used metabolomic approaches for a decade or so, mainly applied to organic residues adhering to archaeological materials. Because of advances in sensitivity, resolution, and the increased availability of different analytical platforms, combined with the low mass/volume required for analysis, metabolomics is now becoming a more feasible choice in the archaeological sector. Additional approaches, as presented by our group, show the versatility of metabolomics as a source of knowledge about the human past when using human osteoarchaeological remains. There is tremendous potential for metabolomics within archaeology, but further efforts are required to position it as a routine technique.</p

Examination of human osteoarchaeological remains as a feasible source of polar and apolar metabolites to study past conditions

Metabolomics is a modern tool that aids in our understanding of the molecular changes in organisms. Archaeological science is a branch of archaeology that explores different archaeological materials using modern analytical tools. Human osteoarchaeological material are a frequent finding in archaeological contexts and have the potential to offer information about previous human populations, which can be illuminating about our current condition. Using a set of samples comprising different skeletal elements and bone structures, here we explore for the first time the possibility of extracting metabolites from osteoarchaeological material. Here, a protocol for extraction and measurement of extracted polar and less-polar/apolar metabolites by ultra-high performance liquid chromatography hyphenated to high resolution mass spectrometry is presented to measure the molecules separated after a reversed phase and hydrophilic interaction liquid chromatography column. Molecular information was obtained, showing that osteoarchaeological material is a viable source of molecular information for metabolomic studies

Examination of human osteoarchaeological remains as a feasible source of polar and apolar metabolites to study past conditions

Metabolomics is a modern tool that aids in our understanding of the molecular changes in organisms. Archaeological science is a branch of archaeology that explores different archaeological materials using modern analytical tools. Human osteoarchaeological material are a frequent finding in archaeological contexts and have the potential to offer information about previous human populations, which can be illuminating about our current condition. Using a set of samples comprising different skeletal elements and bone structures, here we explore for the first time the possibility of extracting metabolites from osteoarchaeological material. Here, a protocol for extraction and measurement of extracted polar and less-polar/apolar metabolites by ultra-high performance liquid chromatography hyphenated to high resolution mass spectrometry is presented to measure the molecules separated after a reversed phase and hydrophilic interaction liquid chromatography column. Molecular information was obtained, showing that osteoarchaeological material is a viable source of molecular information for metabolomic studies

Characteristics of included studies.

<p>Characteristics of included studies.</p