Diet-Induced Early Inflammatory Response of Visceral Adipose Tissue in Healthy Male Wistar Rats.

The prolonged consumption of a high-fat diet (HFD) leads to abnormal growth of the visceral adipose tissue (VAT), increased macrophage infiltration, and altered secretion of biologically active molecules. This is considered as a precondition for the development of obesity, inflammation, and obesity-related disorders. Therefore, we studied HFD-induced changes in the tissue levels of the inflammatory markers C-reactive protein, serum amyloid-A, and interleukin-4 in healthy male Wistar rats. The animals were first divided at random into two groups subjected to either a standard or a high-fat diet. The initial effect of the diet was evaluated after fourteen weeks. In order to study the diet duration effect, the standard diet was given to twelve animals from the HFD group, while the remaining continued with the HFD for an additional four weeks. Our results showed that the HFD barely affected body mass index, conicity, relative fat mass, and Lee indices, whereas it provoked adipocyte hypertrophy and gradually increased the levels of both the pro- and anti-inflammatory markers. The switch from the high-fat to the standard diet resulted in the comparatively fast restoration of the baseline levels of the studied molecules. Although, the prolonged consumption of an HFD causes adipocyte hypertrophy in healthy male animals, the inflammatory process in VAT is well-coordinated, time-dependent, and reversible.

Changes in the levels of marker molecules salivary α-amylase and cortisol as a stress response to everyday activities of general practitioners in rural areas of the Republic of Bulgaria.

INTRODUCTION: Stress is a phenomenon accompanying everyday life. Various reactions of the body are activated during stress, including activation of the hypothalamo-pituitary-adrenal endocrine axis and the autonomous nervous system. Their activity could be assessed by the measurement of biological stress marker molecules - salivary α-amylase and cortisol - on one side and heart rate, and blood pressure monitoring, on the other. The aim of the present study is to determine whether the daily professional routines cause stress development among general practitioners (GPs) who work in rural, distant areas in the territory of the Republic of Bulgaria. METHODS: One hundred and twenty-eight GPs were asked to answer a questionnaire to assess their health conditions, habits, priority objectives and interests, as well as their moral and ethical relationships with the patients. On this basis 40 participants were selected and outlined for the present survey (n=40, mean age 55.92±8.8). Four salivary samples were collected from each participant during 1 week: two on Monday (one in the morning and one after work) and two on Friday, by the same mechanism. The salivary samples collection was followed by measurement of blood pressure and pulse. This non-invasive survey was based on an ELISA method for quantitative determination of the marker molecules in saliva. The blood pressure and pulse were measured by blood pressure monitor. RESULTS: The levels of the salivary α-amylase were significantly higher at the end of the working day, especially on Friday (142.28±23.34 U/mL, p=0.018), but not between the beginning and the end of the week. The normal cortisol awakening response, characterized by a peak in the levels of cortisol after wake-up, followed by a slow decrease during the day, was detected only at the beginning of the week. The data show a significant impairment of this regularity at the end of the week. Moreover, the levels of cortisol, measured for the morning samples, show a decrease at the end of the week (25.73±10.51 ng/mL) in comparison to the beginning of the week (30.1±10.84, p=0.033). The analyses on the effect of smoking (p=0.002) and alcohol consumption (p=0.036) on stress development show a significant increase in the levels of the salivary α-amylase, but not on the levels of salivary cortisol. The changes in the blood pressure indicate stress development at the end of the week (p=0.04), while the pulse showed changes within a day rather than during the week. The values of the pulse were higher at the end of the day. CONCLUSION: The professional lives of the GPs who work in distant and rural places are associated with stress development. Different habits from the daily routine, such as alcohol consumption, smoking and physical activity, could be considered as modulators of stress development.

Xylooligosaccharides and aerobic training regulate metabolism and behavior in rats with streptozotocin-induced type 1 diabetes.

Type 1 diabetes mellitus is characterized with decreased microbial diversity. Gut microbiota is essential for the normal physiological functioning of many organs, especially the brain. Prebiotics are selectively fermentable oligosaccharides [xylooligosaccharides (XOS), galactooligosaccharides, etc.] that promote the growth and activity of gut microbes and influence the gut-brain axis. Aerobic exercise is a non-pharmacological approach for the control of diabetes and could improve cognitive functions. The potential beneficial effect of XOS and/or aerobic training on cognition, the lipid profile and oxidative stress markers of experimental rats were evaluated in this study. Male Wistar rats were randomly divided into three streptozotocin-induced diabetic groups and a control group. Some of the rats, either on a XOS treatment or a standard diet, underwent aerobic training. The results showed that the aerobic training independently lowered the total cholesterol levels compared to the sedentary diabetic rats (p = 0.032), while XOS lowers the malondialdehyde levels in the trained diabetic rats (p = 0.034). What is more the exercise, independently or in combination with XOS beneficially affected all parameters of the behavioral tests. We conclude that aerobic exercises alone or in a combination with the prebiotic XOS could ameliorate the dyslipidemia, oxidative stress, and cognitive abilities in experimental type 1 diabetic animals.

High lipid diet and the expression of proinflammatory markers in testis.

Abstract.

Effect of oligosaccharides on the antioxidant, lipid and inflammatory profiles of rats with streptozotocin-induced diabetes mellitus.

Prebiotics, gut microbiota-fermentable substances, delay the development of type I diabetes. In the present study, we investigated the effect of two prebiotics (galacto-oligosaccharides and xylo-oligosaccharides) on the antioxidant protection, lipid profile, and inflammatory activity of rats with streptozotocin-induced diabetes. The following markers were studied - malondialdehyde, 8-hydroxy-2'-deoxyguanosine, ferric reducing ability of plasma (FRAP), triacylglycerols, total cholesterol (TC), high-density lipoproteins, C-reactive protein (CRP), and interleukin-6. Diabetes was induced in male Wistar experimental rats by streptozotocin injection, while the non-diabetic controls were injected with saline. Afterward the oligosaccharides were administered orally to the experimental animals. The blood collected following the decapitation was analyzed by ELISA. A modified protocol was used only for measuring the FRAP values. The galacto-oligosaccharides and xylo-oligosaccharides lowered the malondialdehyde levels in the diabetic rats (p < 0.05). The galacto-oligosaccharides decreased the serum levels of 8-hydroxy-2'-deoxyguanosine (p = 0.01), while the xylo-oligosaccharides increased the FRAP (p < 0.05) in the experimental animals. None of the oligosaccharides affected triacylglycerol and interleukin-6 concentrations, but the galacto-oligosaccharides decreased the TC and CRP levels in the diabetic animals. Both oligosaccharides exert a beneficial effect on the antioxidant protection of the diabetic rats, but have a minor effect on their lipid and inflammatory profiles.

Impact of a High-fat Diet on the Development of Chronic Inflammation in Heart of Wistar rats.

INTRODUCTION: Obesity is linked to the development of low-grade, chronic inflammation. Obesity-related inflammation appears to be a different type of inflammation, mainly due to excessive food intake and unusual homeostasis. It can be evaluated by measuring the concentration of pro- and anti-inflammatory marker molecules ­ C-reactive protein (CRP), serum amyloid-A (SAA) and interleukin-4. AIM: The aim of the present study is to evaluate the rate of the inflammatory process in heart, provoked by the consumption of a high-fat diet. MATERIALS AND METHODS: Sixty 8-week-old male Wistar rats were used in this experiment. The laboratory animals were fed orally with two different types of rodent food for 14 or 18 weeks ­ a high-fat diet (experimental groups) and standard rodent food (control groups). They all were kept under standard housing conditions. The levels of the pro- and anti-inflammatory markers in tissue homogenates from heart were analyzed using ELISA. Their expression in tissue samples was detected immunohistochemically by the biotin-streptavidin-peroxidase method. The total protein concentration was determined by the Lawry method. RESULTS: CRP levels showed no significant differences when the control group was compared with the groups fed with a high-fat diet (p>0.05). The SAA levels detected were also insignificantly changed. Only the IL-4 tissue levels showed tendency to increase (p<0.05) in the high-fat diet group. CONCLUSIONS: Our experiment indicates that there is a specific reaction of the heart to a high-fat diet. It also refers to the existence of adaptive mechanisms allowing the heart to counteract the development of dietary induced inflammation.