Selenium and its relationship to cancer: an update

Selenomethionine (Semet) is the major seleno-compound in cereal grains and enriched yeast whereas Se-methylselenocysteine (SeMCYS) is the major seleno-compound in Se-accumulator plants and some plants of economic importance such as garlic and broccoli exposed to excess Se. Animals can metabolize both Semet and SeMCYS. Epidemiological studies have indicated an inverse relationship between Se intake and the incidence of certain cancers. Blood or plasma levels of Se are usually lower in patients with cancer than those without this disorder, but inconsistent results have been found with toenail-Se values and the incidence of cancer. There have been eight trials with human subjects conducted on the influence of Se on cancer incidence or biomarkers, and except for one, all have shown a positive benefit of Se on cancer reduction or biomarkers of this disorder. This is consistent with about 100 small-animal studies where Se has been shown to reduce the incidence of tumours in most of these trials. Se-enriched yeast is the major form of Se used in trials with human subjects. In the mammary-tumour model, SeMCYS has been shown to be the most effective seleno-compound identified so far in reduction of tumours. Several mechanisms have been proposed on the mechanism whereby Se reduces tumours. Even though SeMCYS was shown to be the most effective seleno-compound in the reduction of mammary tumours, it may not be the most effective seleno-compound for reduction of colon tumours.

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Nutritional programming of gastrointestinal tract development. Is the pig a good model for man?

Nutrition Research Reviews ◽

10.1017/s0954422410000077 ◽

2010 ◽

Vol 23 (1) ◽

pp. 4-22 ◽

Cited By ~ 172

Author(s):

Paul Guilloteau ◽

Romuald Zabielski ◽

Harald M. Hammon ◽

Cornelia C. Metges

Keyword(s):

Gastrointestinal Tract ◽

Animal Models ◽

Animal Studies ◽

Reference Model ◽

Human Subjects ◽

Mammalian Species ◽

Epidemiological Studies ◽

Long Term Effects ◽

Nutritional Programming ◽

The Impact

The consequences of early-life nutritional programming in man and other mammalian species have been studied chiefly at the metabolic level. Very few studies, if any, have been performed in the gastrointestinal tract (GIT) as the target organ, but extensive GIT studies are needed since the GIT plays a key role in nutrient supply and has an impact on functions of the entire organism. The possible deleterious effects of nutritional programming at the metabolic level were discovered following epidemiological studies in human subjects, and confirmed in animal models. Investigating the impact of programming on GIT structure and function would need appropriate animal models due to ethical restrictions in the use of human subjects. The aim of the present review is to discuss the use of pigs as an animal model as a compromise between ethically acceptable animal studies and the requirement of data which can be interpolated to the human situation. In nutritional programming studies, rodents are the most frequently used model for man, but GIT development and digestive function in rodents are considerably different from those in man. In that aspect, the pig GIT is much closer to the human than that of rodents. The swine species is closely comparable with man in many nutritional and digestive aspects, and thus provides ample opportunity to be used in investigations on the consequences of nutritional programming for the GIT. In particular, the ‘sow–piglets’ dyad could be a useful tool to simulate the ‘human mother–infant’ dyad in studies which examine short-, middle- and long-term effects and is suggested as the reference model.

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Nutrition and its contribution to obesity and diabetes: a life-course approach to disease prevention?

Proceedings of The Nutrition Society ◽

10.1017/s0029665108008872 ◽

2008 ◽

Vol 68 (1) ◽

pp. 71-77 ◽

Cited By ~ 11

Author(s):

Michael E. Symonds

Keyword(s):

Animal Studies ◽

Dietary Intervention ◽

Human Subjects ◽

Disease Onset ◽

Small Animal ◽

Extended Period ◽

Major Influence ◽

Relative Contribution ◽

Obesity And Diabetes

Whilst previously type 2 diabetes occurred in older adults, its incidence, together with obesity, has increased rapidly in children. An improved understanding of this disease pathway from a developmental view point is critical. It is likely that subtle changes in dietary patterns over an extended period of time contribute to diabetes, although this type of rationale is largely ignored in animal studies aimed at determining the mechanisms involved. Small-animal studies in which large, and often extreme, changes in the diet are imposed at different stages of the life cycle can have substantial effects on fat mass and/or pancreatic functions. These responses are not representative of the much more gradual changes seen in the human population. An increasing number of studies indicate that it is growth rate per se, rather than the type of dietary intervention that determines pancreatic function during development. Epigenetic mechanisms that regulate insulin secretion by the pancreas can be re-set by more extreme changes in dietary supply in early life. The extent to which these changes may contribute to more subtle modulations in glucose homeostasis that can accompany excess fat growth in childhood remains to be established. For human subjects there is much less information as to whether specific dietary components determine disease onset. Indeed, it is highly likely that genotype has a major influence, although recent data relating early diet to physical activity and the FTO gene indicate the difficulty of establishing the relative contribution of diet and changes in body mass to diabetes.

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’Animal Studies‘, Disziplinarität und die (Post-)Humanities

Zeitschrift für Medien- und Kulturforschung ◽

10.28937/1000106387 ◽

2013 ◽

Vol 4 (1) ◽

Author(s):

Cary Wolfe

Keyword(s):

Social Communication ◽

Animal Studies ◽

Human Subjects

Der Text von Cary Wolfe ist eine gekürzte Übersetzung des Kapitels »Animal Studies«, Disciplinarity, and the (Post)Humanities aus der Monographie What is Posthumanism? (Minnesota 2009). Wolfe diskutiert die Beziehung zwischen (Trans-)Disziplinarität und Posthumanismus im Rückgriff auf Konzepte von Derrida, Foucault und Luhmann, die eine Form von gesellschaftlicher Kommunikation zu denken erlauben, an der menschliche Subjekte zwar noch teilhaben, aber deren souveräne Urheber sie nicht mehr sind </br></br>The paper by Cary Wolfe is an abridged translation of the chapter »Animal Studies«, Disciplinarity, and the (Post)Humanities from the monograph (Minnesota 2009). Wolfe discusses the relation between (trans-)disciplinarity and posthumanism with reference to concepts by Derrida, Foucault and Luhmann, allowing to consider a form of social communication in which human subjects still may participate, but no longer are their sovereign initiators.

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Antidiabetic Properties of Naringenin: A Citrus Fruit Polyphenol

Biomolecules ◽

10.3390/biom9030099 ◽

2019 ◽

Vol 9 (3) ◽

pp. 99 ◽

Cited By ~ 16

Author(s):

Danja J. Den Hartogh ◽

Evangelia Tsiani

Keyword(s):

Insulin Resistance ◽

Animal Studies ◽

Citrus Fruit ◽

Epidemiological Studies ◽

Personal Health ◽

Current Review ◽

Vegetables And Fruits

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by insulin resistance and hyperglycemia and is associated with personal health and global economic burdens. Current strategies/approaches of insulin resistance and T2DM prevention and treatment are lacking in efficacy resulting in the need for new preventative and targeted therapies. In recent years, epidemiological studies have suggested that diets rich in vegetables and fruits are associated with health benefits including protection against insulin resistance and T2DM. Naringenin, a citrus flavanone, has been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, immunomodulatory and antidiabetic properties. The current review summarizes the existing in vitro and in vivo animal studies examining the anti-diabetic effects of naringenin.

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Development of the Biostator Glucose clamping algorithm.

Clinical Chemistry ◽

10.1093/clinchem/28.9.1899 ◽

1982 ◽

Vol 28 (9) ◽

pp. 1899-1904 ◽

Cited By ~ 24

Author(s):

A H Clemens ◽

D L Hough ◽

P A D'Orazio

Keyword(s):

Animal Studies ◽

Insulin Infusion ◽

Blood Glucose Concentration ◽

Human Subjects ◽

Pancreatic Beta Cell ◽

Model System ◽

Exogenous Insulin ◽

Maturity Onset Diabetes ◽

Beta Cell Response ◽

Infusion System

Abstract The "glucose clamping" technique has been proposed as a method for the early detection of a beginning derangement of glucose homeostasis and thus for the possible prevention of maturity-onset diabetes. This technique interrupts the physiological glucose-insulin relationship by placing a patient's blood glucose concentration under an investigator's control, for quantification of the pancreatic beta-cell response during hyperglycemic clamps and of sensitivity of body tissue to exogenous insulin during normoglycemic clamps. We report the development of a glucose clamping algorithm for use with the Biostator glucose-controlled insulin-infusion system (Horm. Metab. Res., Suppl. 8: 23-33, 1977). This algorithm adds simplicity and precision to the glucose clamping procedure and reduces operator effort to a minimum. We describe the early development of the algorithm with a model system and report evaluations made during animal studies and preliminary investigations with human subjects.

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Inverse Relationship Between Serum Bilirubin and Atherosclerosis in Men: A Meta-Analysis of Published Studies

Experimental Biology and Medicine ◽

10.1177/15353702-0322805-29 ◽

2003 ◽

Vol 228 (5) ◽

pp. 568-571 ◽

Cited By ~ 211

Author(s):

Ladislav Novotný ◽

Libor Vítek

Keyword(s):

Inverse Relationship ◽

Serum Bilirubin ◽

Linear Trend ◽

Meta Analysis ◽

Negative Relationship ◽

Epidemiological Studies ◽

Atherosclerotic Disease ◽

Categorical Variables ◽

History Of ◽

Stratified Analysis

Bilirubin, a major intravascular product of heme catabolism, is a potent antioxidant compound. Numerous studies have been published showing the relationship between serum bilirubin levels and atherosclerosis. In the present investigation all the epidemiological studies available on the effect of serum bilirubin levels and atherosclerotic disease were analyzed. Studies on the epidemiology of atherosclerotic diseases in relation to serum bilirubin levels were searched in the MEDLINE database. Selected studies were subdivided according to serum bilirubin levels and severity of atherosclerotic disease. Because of the limited number of females involved in the studies, only males were included into meta-analysis. Associations for ordered categorical variables (bilirubin and natural history of graded atherosclerosis) were assessed to find correlation and linear trend between analyzed variables. A stratified analysis was conducted to compare risks of clinical outcomes. Eleven relevant studies were used for analysis. A close negative relationship was found between serum bilirubin levels and severity of atherosclerosis (Spearman rank coefficient r = −0.31, P < 0.0001). The linear trend was confirmed in analysis of proportions with x2 values for both disease conditions to be very significant ( P < 0.0001). Unambiguous inverse relationship between serum bilirubin levels and atherosclerosis was demonstrated in this preliminary meta-analytic study. These results indicate the importance of hem oxygenase-related products in the prevention of oxidative stress-mediated diseases.

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Prenatal exposure to persistent organic pollutants as a risk factor of offspring metabolic syndrome development during childhood

Reviews on Environmental Health ◽

10.1515/reveh-2020-0113 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Marlene Cervantes González

Keyword(s):

Metabolic Syndrome ◽

Organic Pollutants ◽

Prenatal Exposure ◽

Persistent Organic Pollutants ◽

Animal Studies ◽

Polychlorinated Biphenyl ◽

Environmental Pollutants ◽

Epidemiological Studies ◽

Experimental Findings

Abstract Persistent Organic Pollutants (POPs) are exogenous, artificially made chemicals that can disrupt the biological system of individuals and animals. POPs encompass a variety of chemicals including, dioxins, organochlorines (OCs), polychlorinated biphenyl (PCBs), and perfluoroalkyl substances (PFASs) that contain a long half-life and highly resistant to biodegradation. These environmental pollutants accumulate over time in adipose tissues of living organisms and alter various insulin function-related genes. Childhood Metabolic Syndrome (MetS) consists of multiple cardiovascular risk factors, insulin function being one of them. Over the years, the incidence of the syndrome has increased dramatically. It is imperative to explore the role of persistent organic pollutants in the development of Childhood Metabolic Syndrome. Some epidemiological studies have reported an association between prenatal exposure to POPs and offspring MetS development throughout childhood. These findings have been replicated in animal studies in which these pollutants exercise negative health outcomes such as obesity and increased waist circumference. This review discusses the role of prenatal exposure to POPs among offspring who develop MetS in childhood, the latest research on the MetS concept, epidemiological and experimental findings on MetS, and the POPs modes of action. This literature review identified consistent research results on this topic. Even though the studies in this review had many strengths, one major weakness was the usage of different combinations of MetS criteria to measure the outcomes. These findings elucidate the urgent need to solidify the pediatric MetS definition. An accurate definition will permit scientists to measure the MetS as a health outcome properly and allow clinicians to diagnose pediatric MetS and provide individualized treatment appropriately.

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