The pathophysiological role of physical inactivity and fat-diet to development of metabolic syndrome in an animal model

RESUMO Esta tese é suportada por uma revisão narrativa da literatura, perspetivando fornecer uma visão geral dos principais aspetos etiológicos, fisiopatológicos e clínicos da síndrome metabólica, assim como por três artigos originais, utilizando um modelo animal, que objetivaram identificar a contribuição isolada e conjugada da inatividade física e de uma dieta hiperlipídica no desenvolvimento da síndrome metabólica. Para tal, ratos Wistar machos foram alimentados com dieta hiperlipídica e/ou tiveram a atividade física restrita ao espaço da gaiola por 21 semanas. Os resultados revelaram que a dieta hiperlipídica e a inatividade física induziram um característico fenótipo adulto, com ratos maiores e mais leves, possuindo órgãos mais leves e uma expressiva deposição de gordura retroperitoneal sem, contudo, ganho de peso. Os trabalhos empíricos também revelaram a predominância da dieta gorda sobre a inatividade física na indução de desarranjos metabólicos, uma vez que apenas os animais alimentados com dieta gorda desenvolveram síndrome metabólica, independentemente dos níveis de atividade física, com maladaptações hepáticas e do pâncreas endócrino evidenciando uma intensa resposta inflamatória, aumento do conteúdo local de colágeno e da apoptose celular em ambos os órgãos. Estes resultados permitem concluir que a dieta rica em gordura é um fator patogénico predominante na indução da síndrome metabólica e das maladaptações hepáticas e pancreáticas em um modelo animal, comparativamente à inatividade física. Ainda assim, comparativamente à dieta gorda, mais determinante na indução da intolerância à glicose, a inatividade física parece ser mais decisiva no comprometimento da sensibilidade à insulina. Níveis mais elevados de atividade física não parecem prevenir o desenvolvimento da síndrome metabólica e das alterações orgânicas associadas após 21 semanas de protocolo experimental, mas atenuam os transtornos metabólicos e estruturais induzidos pela dieta gorda. Palavras Chave: Physical inactivity, fat diet, metabolic syndrome, liver disorder, and endocrine pancreas disarrangement.This thesis is supported by a literature narrative review aiming to provide an overview of the metabolic syndrome main etiological, pathophysiological and clinical aspects, as well as three original articles using an animal model that aimed to identify the physical inactivity and the hyperlipidic diet isolated and conjugated contribution in the metabolic syndrome development. For this, male Wistar rats were fed with a high-fat diet and/or had the physical activity restricted to the cage space for 21 weeks. The results revealed that the high-fat diet and physical inactivity induced a singular adult phenotype, with larger and lighter rats, having lighter organs and an expressive retroperitoneal fat deposition without, however, gaining weight. The empirical studies also revealed the high-fat diet predominance over physical inactivity in inducing metabolic disorders, since only high-fat diet fed-animals developed metabolic syndrome, regardless of physical activity levels, with the hepatic and endocrine pancreas maladaptations evidencing an intense inflammatory response, increased local collagen content and cellular apoptosis in both organs. These results allow us to conclude that the high-fat diet is a predominant pathogenic factor in inducing the metabolic syndrome and the hepatic and pancreatic maladaptations in an animal model, compared to physical inactivity. Nevertheless, in comparison to the high-fat diet, which is more important in the glucose intolerance induction, physical inactivity seems to be more decisive in the impairment of insulin sensitivity. Higher levels of physical activity do not seem to prevent the metabolic syndrome development and related organic changes after 21 weeks of experimental protocol but attenuate the metabolic and structural disorders induced by the high-fat diet

Spine Lifting Biomechanics Between Varying Occupational Activity Levels And Recreational Physical Activity Levels

Background: Moderate to vigorous physical activity as the optimum movement patterns for health have continued to be the dominant focus of health and fitness research. Yet, emerging evidence of deleterious, adverse health effects of prolonged inactivity, independent of regular physical activity, presents a new element to establishing the ideal model of movement patterns for health. The musculoskeletal trunk of the body becomes unbalanced as a result of prolonged inactivity, and a biomechanical analysis can help to identify high-risk loading behavior associated with these unbalances. Moreover, poor spine biomechanics can indicate a need for adjustment to present recommendations for optimum movement patterns. Some research of spine biomechanics associated with sedentary occupation or lifestyle exists. However, up to the author’s knowledge, no research exists on sedentary lifestyle independent of recreational physical fitness in respect to spine biomechanics. Purpose: The purpose of this study was to identify biomechanical patterns and significant differences in lifting biomechanics among individuals who are occupationally inactive and active, as well as recreationally active and inactive. Methods: Participants were divided into four groups using the Cambridge EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk Physical Activity Questionnaire (EPAQ2): inactive, moderately inactive, moderately active, and active. A total of 23 participants completed the protocol. Spine kinematics of lifting was collected through VICON motion capture system. Additionally, ground reaction forces (GRF) and ground reaction moments (GRM) were collected by forceplate. Kinematic dependent variables were calculated from joint angle curves of trunk segments; included was maximum angular displacement of the middle trunk and lower trunk. Kinetic dependent variables were calculated from the GRF and GRM data, including maximum anterior excursion, maximum anterior velocity, and sway area of the center of pressure (COP) trajectories. Difference of each dependent variable between groups was detected by 1-way ANOVA. When difference existed, post-hoc pair-wise comparisons were conducted and Bonferroni correction was applied to minimize family-wise errors. The significance level was set at α = 0.05. Hypothesis: Participants who maintain an inactive lifestyle, regardless of recreational physical activity, will exhibit significantly different lifting biomechanics when compared to the lifting biomechanics of an active population performing the same lifting tasks. Results: Results indicated a statistically significant difference in flexion range of motion for the inactive group compared to all other groups (p=0.014). The inactive group had a significantly lower degree of flexion range of motion. Joint kinematic data indicated little difference between groups for the reaching phase and lift up phase of straight leg lifts. For bent leg lifts, the active population had significantly greater middle trunk flexion displacement during the reaching phase (p=0.005) and lifting phase (p=0.023) of bent leg lifts. No other significant differences existed between the other groups. Analysis of force platform data produced no significant differences between groups. Percent flexion range of motion was significantly different for the active population during the bent leg reaching phase and lifting phase compared with all other groups. The active population used a much larger degree of their total flexion range of motion to reach and lift up the box from the ground. Discussion: The current study aimed to investigate the effect of a largely inactive lifestyle, independent of regular participation in planned physical exercise, on spine kinematics, center of pressure, and range of motion. Results show evidence of a tendency for greater range of motion and greater flexion displacement of the active sample. Although not statistically significant, the inactive sample findings unexpectedly indicated a tendency for increased flexion displacement compared with the moderately active and moderately inactive groups. The moderately inactive group did not have any significant differences when compare to the moderately active group, which did not support the original hypothesis. However, the inactive group had poorer range of motion compared with all other groups, which supports the initial predictions. In summary, the inactive group presented some evidence of poor biomechanics. The active group shosigns of increased range of motion and flexibility. Finally, the moderately active and moderately inactive groups were very similar among all calculated variables. These findings support previous evidence of regular activity improving range of motion and flexibility. Occupational inactivity coupled with regular recreational activity appears to reduce the risk of developing poor lifting biomechanics

Impacts of Diet and Exercise on Maternal Gut Microbiota Are Transferred to Offspring

Background: It is well established that maternal exercise during pregnancy improves metabolic outcomes associated with obesity in mothers and offspring, however, its effects on the gut microbiota of both mother and offspring, are unknown. Here, we investigated whether wheel running exercise prior to and during pregnancy and prolonged feeding of an obesogenic diet were associated with changes in the gut microbiomes of Sprague-Dawley rat dams and their offspring. Female rats were fed either chow or obesogenic diet, and half of each diet group were given access to a running wheel 10 days before mating until delivery, while others remained sedentary. 16S rRNA gene amplicon sequencing was used to assess gut microbial communities in dams and their male and female offspring around the time of weaning.Results: Statistical analyses at the operational taxonomic unit (OTU) level revealed that maternal obesogenic diet decreased gut microbial alpha diversity and altered abundances of bacterial taxa previously associated with obesity such as Bacteroides and Blautia in dams, and their offspring of both sexes. Distance based linear modeling revealed that the relative abundances of Bacteroides OTUs were associated with adiposity measures in both dams and offspring. We identified no marked effects of maternal exercise on the gut microbiota of obesogenic diet dams or their offspring. In contrast, maternal exercise decreased gut microbial alpha diversity and altered the abundance of 88 microbial taxa in offspring of control dams. Thirty of these taxa were altered in a similar direction in offspring of sedentary obesogenic vs. control diet dams. In particular, the relative abundances of Oscillibacter OTUs were decreased in offspring of both exercised control dams and sedentary obesogenic diet dams, and associated with blood glucose concentrations and adiposity measures. Analyses of predicted bacterial metabolic pathways inferred decreased indole alkaloid biosynthesis in offspring of both obesogenic diet and exercised control dams.Conclusions: Our data suggest that maternal exercise prior to and during pregnancy resulted in gut dysbiosis in offspring of control dams. Importantly, alterations in the maternal gut microbiota by obesogenic diet or obesity were transferred to their offspring

Role of a Critical Visceral Adipose Tissue Threshold (CVATT) in Metabolic Syndrome: Implications for Controlling Dietary Carbohydrates: A Review

There are likely many scenarios and pathways that can lead to metabolic syndrome. This paper reviews mechanisms by which the accumulation of visceral adipose tissue (VAT) may contribute to the metabolic syndrome, and explores the paradigm of a critical VAT threshold (CVATT). Exceeding the CVATT may result in a number of metabolic disturbances such as insulin resistance to glucose uptake by cells. Metabolic profiles of patients with visceral obesity may substantially improve after only modest weight loss. This could reflect a significant reduction in the amount of VAT relative to peripheral or subcutaneous fat depots, thereby maintaining VAT below the CVATT. The CVATT may be unique for each individual. This may help explain the phenomena of apparently lean individuals with metabolic syndrome, the so-called metabolically normal weight (MONW), as well as the obese with normal metabolic profiles, i.e., metabolically normal obese (MNO), and those who are "fit and fat." The concept of CVATT may have implications for prevention and treatment of metabolic syndrome, which may include controlling dietary carbohydrates. The identification of the CVATT is admittedly difficult and its anatomical boundaries are not well-defined. Thus, the CVATT will continue to be a work in progress

Periodontal disease severity-correlation with diabetes and obesity measures?

This paper studies the correlation between three widely common chronic diseases, periodontal disease, diabetes, and obesity. The three diseases share one key factor; they not only affect human's health but also the style and quality of life. This paper evaluated the current literature regarding periodontal disease, diabetes, obesity, and their triangular relationship. The studies showed that the three chronic diseases are related to each other in a triangular relationship. Increased adiposity manifested by BMI greater than 30, leads to increased systemic inflammation through the release of inflammatory adipokines from the fatty deposits, this leads to the development of diabetes mellitus by different mechanisms, partly by destruction of the islet cells of Langerhans and partly by insulin resistance. One of the complications of diabetes mellitus is periodontal disease, which is a list of clinical conditions that adversely affect the health of the periodontium. Moreover, current literature provides evidence that the relationship between diabetes and periodontal disease is bidirectional. Evidence from current studies is showing that periodontal disease might lead to the development of diabetes by increasing the systemic inflammation, this occurs by the invasion of periodontal pathogens of the endothelial cells where they elicit an exacerbated systemic inflammation which might lead to the development of diabetes and other chronic conditions. This paper shows the importance of collaborative work between the dental and the medical professionals to ensure the overall health of an individual. Primary care physicians are encouraged to refer patients with poor glycemic control to dentists for an assessment of the health of their oral cavity and vice versa; dentists should be more aware of the systemic complications of oral diseases and should educate their patients about such relationships

25(OH)D levels in trained versus sedentary university students at 64° north

Purpose: 25-hydroxyvitamin D (25[OH]D) deficiency is associated with compromised bone mineralisation, fatigue, suppressed immune function and unsatisfactory skeletal muscle recovery. We investigated the risk of 25(OH)D insufficiency or deficiency in endurance athletes compared to sedentary non-athletes living at 64° north. Methods: University student-athletes (TS) and sedentary students (SS) volunteered to participate in this study. TS engaged in regular exercise while SS exercised no more than 20 minutes/week. Metabolic Equivalent of Task (MET) scores for participants were determined. Vitamin D intake was assessed using the National Cancer Institute’s 24-hour food recall (ASA24). Fasting plasma 25(OH)D levels were quantified via enzyme-linked immunosorbent assay. Results: TS reported higher activity levels than SS as assessed with MET-minutes/week and ranking of physical activity levels (p < 0.05). The reported mean daily intake of vitamin D was higher in TS compared to SS (p < 0.05) while 25(OH)D plasma levels were lower in TS than in SS (p < 0.05). In total, 43.8% of the TS were either insufficient (31.3%) or deficient (12.5%) in 25(OH)D, while none of the SS were insufficient and 13.3% were deficient. Conclusion: TS are at increased risk of 25(OH)D insufficiency or deficiency compared to their sedentary counterparts residing at the same latitude, despite higher vitamin D intake

Influence of Perceived Stressful Homework on Lifestyle Habits and Subsequently on Adiposity : a QUALITY Study

Contexte : Les devoirs perçus stressants semblent avoir un effet négatif sur l’adiposité des enfants entre 8-10 ans et l’activité physique d’intensité moyenne-élevée (APMV) et le temps-écran sont des médiateurs dans cette relation. Objectifs : 1) Examiner si un facteur nutritionnel pourrait aussi être un médiateur, 2) Étudier les associations et médiateurs présents à l’âge de 10-12 ans, et 3) Prendre une approche longitudinale sur ces résultats pour étudier ces relations. Méthodes : Les données suivantes de l’étude de QUALITY ont été extraites : durée des devoirs, niveau de stresse et temps-écran, durée de sommeil et APMV, facteurs nutritionnels, et profil d’adiposité. « Process Macro » a été utilisé pour faire les analyses statistiques. Résultats principaux : Les devoirs perçus étant stressants étaient positivement associés avec l’adiposité seulement à 8-10 ans chez les enfants, particulièrement les filles. La consommation de breuvage sucré était un médiateur partiel entre les devoirs perçus étant stressants et le pourcentage de gras abdominal des enfants de 8-10 ans. À 10-12 ans, le temps-écran était le seul médiateur entre les devoirs et l’index de masse corporelle. Le changement dans la durée de sommeil était le seul médiateur entre les changements de devoirs perçus étant stressant et pourcentage de gras abdominal qui s’est produit depuis l’âge de 8-10 ans chez les enfants, particulièrement les filles. Conclusions : Avec l’avancée de l’âge et augmentation des devoirs, les habitudes d’écran changent. Dans l’aspect préventif de l’obésité pédiatrique, le temps-écran et la durée de sommeil pourraient être surveillés de près.Background: Perceived stressful homework was shown to be associated with poor adiposity profile in children aged 8-10 years old, and this was mediated by a decrease in moderate-to-vigorous physical activity (MVPA) and an increase in screen time. Objectives: 1) Explore if any dietary factors could be potential mediator, 2) Observe the associations and mediators present at 10-12 years of age, and 3) Examine from a longitudinal perspective these associations (from 8-10 years old to 10-12 years old). Methods: The following information on the QUALITY cohort children were extracted: homework duration, stress level and screen time, sleep and MVPA duration, dietary factors, and adiposity profile. Process Macro for SPSS was used for the statistical analysis. Main Results: Perceived stressful homework was positively associated with adiposity at 8-10 years old only in all children, particularly in girls. High-sugar drink was a partial mediator between perceived stressful homework and trunk fat percentage in children at 8-10 years old. Screen time mediated the relationship between homework and body mass index of children at 10-12 years old. Sleep duration change mediated the association between perceived stressful homework duration and trunk fat percentage changes in children since ages 8-10 years old, especially in girls. Discussion: As children grow and perform a lot of homework, screen habits changes. In prevention aspect of paediatric obesity, screen time and sleep duration are the two major habits to monitor

So depression is an inflammatory disease, but where does the inflammation come from?

BACKGROUND: We now know that depression is associated with a chronic, low-grade inflammatory response and activation of cell-mediated immunity, as well as activation of the compensatory anti-inflammatory reflex system. It is similarly accompanied by increased oxidative and nitrosative stress (O&NS), which contribute to neuroprogression in the disorder. The obvious question this poses is 'what is the source of this chronic low-grade inflammation?' DISCUSSION: This review explores the role of inflammation and oxidative and nitrosative stress as possible mediators of known environmental risk factors in depression, and discusses potential implications of these findings. A range of factors appear to increase the risk for the development of depression, and seem to be associated with systemic inflammation; these include psychosocial stressors, poor diet, physical inactivity, obesity, smoking, altered gut permeability, atopy, dental cares, sleep and vitamin D deficiency. SUMMARY: The identification of known sources of inflammation provides support for inflammation as a mediating pathway to both risk and neuroprogression in depression. Critically, most of these factors are plastic, and potentially amenable to therapeutic and preventative interventions. Most, but not all, of the above mentioned sources of inflammation may play a role in other psychiatric disorders, such as bipolar disorder, schizophrenia, autism and post-traumatic stress disorder

Effect of oral insulin and hyperlipidic diet on intestinal epithelium and adipose tissue / Efeito da insulina oral e da dieta hiperlipídica no epitélio intestinal e tecido adiposo

O uso de insulina oral vem sendo estudado por seu potencial na reversão da hipertrofia intestinal característica de pacientes diabéticos e obesos. O presente estudo, avaliou a influência da insulina oral na hipertrofia e hiperplasia em adipócitos viscerais e alterações intestinais de ratos Wistar, tratados com dieta hiperlipidica e dieta padrão. Foram divididos 60 ratos em quatro grupos de animais, onde dois grupos foram tratados com ração hiperlipidica e dois grupos com dieta padrão; um grupo de cada tipo de ração recebeu todos os dias 20 UI de insulina oral. Durante 60 dias os animais foram pesados semanalmente e após este período eles foram eutanasiados e coletadas as gorduras e intestino foram realizadas. Houve influência positiva da insulina oral no peso dos animais, nos pesos das gorduras e na redução da hipertrofia dos adipócitos, possivelmente por alterações na microbiota e camada de muco do epitélio intestinal, propiciando um maior efeito incretínico; houve diferença no peso, altura e largura dos vilos intestinais relacionado possivelmente com a ação sensibilidade à insulina. Diante dos resultados encontrados podemos concluir que a insulina oral tem efeito positivo nas alterações intestinais e dos adipócitos em animais alimentados com dietas ricas em gordura