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.

Ostarine blunts the effect of endurance training on submaximal endurance in rats.

The purpose of this study is to study the effects of ostarine alone and in combination with endurance training in sexually mature, male Wistar rats. The rats were divided into a treadmill-trained group and a sedentary group. Half of each group received either ostarine or vehicle for 8 weeks (n = 10 each, in total n = 40). We examined some functional, hormonal, and anthropometric parameters and the myogenic gene expression of myostatin, insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor-A (VEGF-A) in m. gastrocnemius. Ostarine decreased submaximal endurance and increased myogenic gene expression of myostatin but had no effect on maximal time to exhaustion and grip strength. Training increased submaximal endurance, maximal time to exhaustion, and grip strength. Our results indicate that both exercise and ostarine treatment had no significant effects on serum levels of luteinizing hormone, follicle-stimulating hormone, and testosterone, or on the myogenic gene expression of IGF-1 and VEGF-A. Neither ostarine nor the training had a significant effect on the testis, liver, and heart weights. In conclusion, ostarine had no effect on anthropometric and hormonal parameters but increased the myostatin gene expression in muscle. The SARM treatment decreased submaximal endurance without affecting maximal time to exhaustion, and training increased both metrics.

Selective Androgen Receptor Modulators Combined with Treadmill Exercise Have No Bone Benefit in Healthy Adult Rats.

The effects of combination treatments using the selective androgen receptor modulators (SARMs) ostarine (OST) or ligandrol (LIG) with treadmill exercise (TE) were studied in healthy adult rats. Fifteen-week-old male Wistar rats were divided into groups (n = 10/group). Experiment 1 consisted of (1) Control group: sedentary rats receiving vehicle; (2) OST: sedentary rats receiving OST; (3) TE: training rats receiving vehicle; (4) OST + TE: training rats receiving OST. Experiment 2 consisted of (1) LIG: sedentary group receiving LIG; (2) LIG + TE: training group receiving LIG. The TE regime was as follows: 25 m/min, 5° elevation, 40 min, five times/week, and the sedentary regime was 5 min, three times/week. OST and LIG were administered subcutaneously (0.4 mg/kg body weight/day, five times/week). After eight weeks, bone samples underwent microcomputed tomographical, biomechanical, histological, and ashing analyses. All the treatments had weak effects on the bone structure without affecting bone biomechanics. The OST + TE improved bone structure, while the LIG + TE had unfavorable effects. In serum, OST, OST + TE, and LIG + TE altered cholesterol and lipoprotein levels; TE did not change the serum parameters. The SARM treatments had no clear bone benefit, and the serum effects can be considered as side effects. TE represents a safe treatment. Because SARMs are increasingly applied in gyms along with physical activities, attention should be paid to possible side effects.

Rhythm and conduction complications after COVID-19 infection in physiological hypertrophy of myocardium (athlete's heart).

The term 'athletic heart syndrome' (AHS) is used to describe specific circulatory and morphological changes in individuals who participate in sports competitions. The syndrome is characterized by normal cardiac function and reversible myocardial remodelling.The incidence and severity of the post-COVID-19 cardiac pathology in active athletes are so far unclear. One of the complications involving the heart is myocarditis. We present a case of a 23-year-old rower after having a moderate COVID-19 infection. Electrocardiograms showed evidence of a shift in conduction and rhythm disturbances ranging from Group 1 (normal ECG findings) to Group 2 (abnormal ECG findings) on the background of an AHS. Echocardiography (with new methods of evaluating deformity - Global Longitudinal Strain) revealed an area with mildly reduced left ventricular deformity around the apex. To assess the subtle alterations in the myocardium, magnetic resonance imaging was used and focal myocarditis was detected. In our patient, considering the degree of severity of his COVID-19 infection - a moderate one, a decision was taken to perform a clinical and instrumental reassessment of his cardiovascular complications 6 months after the infection.This clinical case presents two substantial issues. First, is the AHS more susceptible to rhythm and conduction disturbances after a COVID-19 infection than that of a person who does not actively participate in sports? Second, what the reversibility or the definitive nature of these disturbances is, and how this impacts the prognosis associated with an active sporting activity.

Aronia melanocarpa Fruit Juice Modulates ACE2 Immunoexpression and Diminishes Age-Related Remodeling of Coronary Arteries in Rats.

The aim of the study is to evaluate the effect of Aronia melanocarpa fruit juice (AMJ) supplementation on age-related coronary arteries remodeled in aged rat hearts. Male Wistar rats (n = 24) were divided into three groups: (1) young controls (CY), aged 2 months, without AMJ supplementation; (2) old controls (CO), aged 27 months, without AMJ supplementation; and (3) the AMJ group (A), which used 27-month old animals, supplemented orally with AMJ for 105 days. AMJ supplementation did not influence the wall-to-diameter parameter (Kernohan index) of the coronary arteries of test animals. Aged rats supplemented with AMJ showed a significant decrease in the amount of collagen fibers in their coronary tunica media, as compared with the old controls. The intensity of the immunoreaction for alpha smooth muscle actin (αSMA) in the coronary tunica media was significantly lower in the supplemented group than in the old controls. The intensity of the angiotensin-converting enzyme 2 (ACE2) immunoreaction in the coronary tunica media of the supplemented group was significantly higher than the one observed in the old controls. These results indicate the positive effects of AMJ supplementation on the age-dependent remodeling of coronary arteries and support for the preventive potential of antioxidant-rich functional food supplementation in age-related diseases.

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.

Black Chokeberry (Aronia melanocarpa) Functional Beverages Increase HDL-Cholesterol Levels in Aging Rats.

Plant-based foods rich in phenolic phytochemicals are among the promising strategies to counteract age-related changes in lipid profile. Aronia melanocarpa (AM) fruits are a rich source of phenolic compounds possessing lipid-modulating effects. The present study investigated the effect of 3-month supplementation of AM-based functional beverages on the lipid profile of healthy aging rats. Male Wistar rats (n = 40) were separated into five groups: (YC) young controls (2-month-old); (AC) adult controls (13-month-old); (A) adult animals supplemented with pure AM extract; (A + P) adult animals supplemented with pectin-enriched (1%) AM extract; (A + H) adult animals supplemented with AM extract enriched with a herbal mixture. Total cholesterol (TC), triglycerides (TG), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C) and atherogenic indices were investigated at the end of the study. Adult controls demonstrated age-related dyslipidemia resulting in decreased HDL-C, and increased TG and TC/HDL index. The supplemented groups showed a significant increase in HDL-C levels: A + P (1.49 mmol/L) and A + H (1.61 mmol/L), respectively, vs. AC (1.09 mmol/L), p < 0.05. The TC/HDL-C and LDL-C/HDL-C indices were decreased in the A + P and A + H groups in comparison to the AC group (p < 0.05). These results indicate that supplementation with polyphenol-rich AM beverages can successfully alter HDL-C levels and this effect is further potentiated by pectin and herbs.

Aronia melanocarpa (Michx.) Elliot fruit juice reveals neuroprotective effect and improves cognitive and locomotor functions of aged rats.

The aim of the study was to investigate the effect of polyphenol-rich Aronia melanocarpa (Michx.) Elliot juice (AMJ) on learning ability and memory, and brain morphology of aged rats. A model of healthy male Wistar rats (24 months of age) divided in 2 groups was used: AMJ group supplemented orally with AMJ (10 mL/kg for 105 days) and old control (CO) group without supplementation. Activity cage test showed that AMJ supplemented rats increased the number of vertical movements compared with old controls (p < 0.05). In active avoidance test, supplemented rats increased the number of avoidances on 3rd, 4th and 5th days of learning session, compared with the respective day of old controls (p < 0.05). AMJ supplementation did not affect the mean neuronal number in the dentate gyrus but significantly increased the density of nerve fibers in the perforant path of the hippocampus (p < 0.05). AMJ supplementation increased acetylcholinesterase activity in hippocampus, which is a marker of improved functional activity of the cholinergic neurons. These results indicate that AMJ induced ameliorating changes in the ability of old rats to learn tasks and improved their locomotor functions. AMJ showed a neuroprotective effect by increasing the density of nerve fibers in the hippocampal perforant pathway.

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.

The effect of flutamide on the physical working capacity and activity of some of the key enzymes for the energy supply in adult rats.

The aim of the study was to assess the effects of androgen receptor antagonists on the physical working capacity and activity of some of the key muscle enzymes for the energy supply in rats. Young adult male Wistar rats were divided into two groups. One group received 15 mg kg-1 of flutamide daily for 6 days a week and the other group served as control for 8 weeks. At the beginning and at the end of the experiment, all rats were subjected to submaximal running endurance (SRE), maximum time to exhaustion (MTE), and maximal sprinting speed (MSS) tests. At the end of the trial, maximum oxygen consumption (VO2max) test was performed and the levels of testosterone, erythrocytes, hemoglobin as well as enzyme activity of succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), and NAD.H2-cytochrome-c reductase (NAD.H2) of the gastrocnemius muscle were measured. Serum testosterone of the flutamide-treated rats was higher than that of the controls, which verifies the effectiveness of the dose chosen. MTE and SRE of the anti-androgen-treated group were lower compared with the initial values. Flutamide treatment decreased the activity of SDH and NAD.H2 compared with the controls. We found no effect of the anti-androgen treatment on MSS, VO2max, running economy, LDH activity, and hematological variables. Our findings indicate that the maintenance of the submaximal and maximal running endurance as well as the activity of some of the key enzymes associated with muscle oxidative capacity is connected with androgen effects mediated by androgen receptors.

Antiatherogenic and Cardioprotective Effects of Black Chokeberry (Aronia melanocarpa) Juice in Aging Rats.

Age-related diseases are a social problem of global significance and their prevention by natural products is a research area of particular interest. The present study is an approach to counteract the risk factors for atherosclerosis arising in the aging process by supplementation of chokeberry juice. It employed a model of healthy adult rats monitored for a number of somatometric, serum lipidogram, and histopathological parameters, related to risk factors and their response to supplementation with antioxidant-rich chokeberry juice. The results were used to calculate different atherogenic and cardioprotective indices, and all results were compared to those of young healthy rats. Chokeberry juice proved an extremely rich source of polyphenols resulting in very high antioxidant activity. Treatment with Aronia juice significantly lowered the proatherogenic low-density lipoprotein fraction of the animals studied and led to a 16.5% decrease in their total cholesterol. Atherogenic indices in Aronia-supplemented animals clearly showed lower atherogenic risk and cardioprotective indices indicated protection of the cardiovascular system. Besides that, chokeberry juice retarded the age-related changes in the aortic wall and can be recommended as a prophylactic tool for healthy aging.

Changes of Bcl-2, Bax and Caspase-3 expression in the dermal microvascular endothelial cells and the epidermal layers of the eschar (tache noire) in patients with Mediterranean spotted fever.

Mediterranean spotted fever (MSF) is widely prevalent in many endemic regions in Bulgaria. The disease is still not quite thoroughly studied as to some aspects of its pathogenesis and especially to issues that concern the crucial signals for apoptosis in the target microvascular endothelial cells. To study the expression of Bcl-2 family proteins and Caspase-3 in the dermal capillary endothelial cells from skin papules and in the eschar (tache noire) epidermal layers of patients with MSF so that we can establish apoptotic processes and the time of their occurrence and deployment. Immunohistochemical reactions for Bcl-2, Bax and Caspase-3 were obtained in slices of punch-biopsies taken from papules of the skin rash and from the eschars of eight patients with MSF. The average intensity of the reactions was compared with that in control punch-biopsy slices from four healthy subjects. MSF was etiologically confirmed in all patients by positive antibody response to a specific antigen, Rickettsia conorii, with indirect immunofluorescent assay performed by the Rickettsial Reference Laboratory. The immune reaction for Bcl-2 was found to be poorly expressed in the capillary endothelial cells of skin papules of patients without any differences from controls. The expression of Bax and Caspase-3 was strongly upregulated in comparison with the controls. The Bcl-2/Bax ratio was significantly decreased. Microvascular endothelial cells of the eschar showed similar changes. While the Bcl-2/Bax ratio decreased in the epidermal layers of the eschar "tache noire", there were no changes in the intensity of the immunoreactivity of Caspase-3 as compared with controls. The upregulation of Bax and Caspase-3 is an indication of ongoing apoptotic processes in the dermal microvascular endothelial cells of MSF patients. The epidermal layers of the eschar showed increased sensitivity to apoptosis, however, executive phase of apoptosis did not occur.

Exercise performance and muscle contractile properties after creatine monohydrate supplementation in aerobic-anaerobic training rats.

The purpose of this study was to investigate the effects of creatine monohydrate supplementation on exercise performance and contractile variables in aerobic-anaerobic training rats. Twenty 90-day-old male Sprague Dawley rats were divided into two groups - creatine (Cr) and controls (K). The creatine group received creatine monohydrate as a nutritional supplement, whereas the control group was given placebo. Both groups were trained 5 days a week on a treadmill for 20 days in a mixed (aerobic-anaerobic) metabolic working regimen (27 m·min(-1), 15% elevation for 40 min). The exercise performance (sprint-test), contractile properties (m. tibialis anterior), oxidative enzyme activity (SDH, LDH, NADH2) in m. soleus and blood hematological and chemical variables were assessed in the groups at the end of the experiment. It was found out that creatine supplementation improved the exercise performance after 20 days of administration in a dose of 60 mg per day on the background of a mixed (aerobic-anaerobic) exercise training. At the end of the trial the Cr-group demonstrated better values for the variables which characterize the contractile properties of m. tibialis anterior containing predominantly types IIA and IIB muscle fibers. On the other hand, a higher oxidative capacity was found out in m. soleus (type I muscle fibers) as a result of 20-day creatine supplementation. No side effects of creatine monohydrate supplementation were assessed by the hematological and blood biochemical indices measured in this study. Key pointsThe creatine monohydrate supplementation of the rats diet improves their exercise performance after 20 days administration in a dose of 60 mg per day on the background of a mixed (aerobic-anaerobic) exercise training.The creatine supplemented rats demonstrate better contractile properties of m. tibialis anterior which muscle contains predominantly types IIA and IIB muscle fibers.The soleus muscle (type I muscle fibers) demonstrates a higher oxidative capacity as a result of 20-days creatine supplementation.

Bcl-2/Bax ratio, mitochondrial membranes and aerobic enzyme activity in cardiomyocytes of rats after submaximal training.

INTRODUCTION: Mitochondria are an active and continuous source of reactive oxygen species (ROS) during respiration. The ROS increased production during endurance training is a result of an augmented electron transport through the respiratory chains, making in this way the mitochondria a potential target for oxidative damage. The Bcl-2 protein family plays a central role in the transition of apoptotic signals towards the mitochondria in stress-induced apoptosis. AIM: The present work studied the effect of endurance training on the expression of the apoptotic proteins Bcl-2 and Bax in rat cardiomyocytes, as well as the concomitant changes in the ultrastructure of the mitochondria and activity of some enzymes residing there. MATERIAL AND METHODS: Two groups of male Wistar rats were used. One was the control and the other was trained on treadmill with submaximal loading for eight weeks. At the end of the trial, samples of the myocardium of all the experimental animals were obtained. Immunohistochemical reactions for Bcl-2 and Bax and enzymehistochemical reactions for succinate dehydrogenase and NADH2-cytochrome C-reductase were done. The results were analyzed using specialized software. Transmission electron microscopical study was carried out too. RESULTS: In the myocardium of the trained animals the expression of Bcl-2 and Bcl-2/Bax ratio were significantly higher compared to the controls. The mitochondria had intact outer and inner membranes, with no signs of swelling. Mitochondria with denser packed cristae were found predominantly. No significant differences were found in the activity of the investigated enzymes in the cardiomyocytes of the animals from both groups. CONCLUSIONS: In the myocardium of the experimental animals endurance training for eight weeks does not lead to activation of apoptotic processes via the mitochondrial pathway. This type of exercise training could be used for cardioprotection in order to elevate apoptotic threshold of cardiomyocytes.

ATP and LPL histochemical activity of rat cardiomyocytes and adipocytes treated with androgenic anabolic steroids.

AIM: To study the effect of short-term and long-term treatment with retabolil, an androgenic anabolic steroid, on the activity of the enzymes ATP and LPL in rat cardiomyocytes and adipocytes. MATERIAL AND METHODS: Six male Wistar rats (mean weight 195-200 g.) were given retabolil 50 mg/kg once subcutaneously, another six were treated with retabolil at the same dose subcutaneously once a week for 6 weeks and another six were used as controls treating them with physiological saline in the same way. After six weeks the animals were sacrificed. Fragments of the left ventricle of the heart and of the subcutaneous tissue from the gluteal region were resected and enzyme-histochemical reactions for ATP and LPL were performed on fresh cryostat sections. RESULTS: The cardiomyocytes of the rats treated only once with retabolil showed no changes in the ATP and LPL activity in comparison with the controls. In the rats given a long-term treatment with retabolil, the enzyme-histochemical reaction for ATP was better expressed while that for LPL was weak. The subcutaneous adipose tissue of the long-term retabolil-treated animals contained some adipocytes that expressed positive LPL and ATP activity. CONCLUSIONS: Our data suggest that androgenic anabolic steroids exert an effect on the activity of the enzymes ATP and LPL in rat cardiomyocytes and adipocytes which depends on the duration of treatment.

Effects of submaximal training and anabolic androgenic steroids administration on steroidogenic enzyme activity in rat Leydig cells.

The purpose of the present study was to investigate the single and combined effects of submaximal training and anabolic androgenic steroids (AAS) treatment on the activity of 3beta hydroxysteroid dehydrogenase (3betaHSD) in rat Leydig cells (LC). Forty male Wistar rats were distributed into 4 groups. Half of them exercised on treadmill. After 2 weeks half of the trained and sedentary rats received weekly either 10 mg x kg(-1) Nandrolone Decanoate (ND) or Placebo (Pl) i.m. for 6 weeks. The day after the last exercises all the groups: 1) sedentary + Pl (SP); 2) sedentary + ND (SND); 3) trained + Pl (TP) and 4) trained + ND (TND) were decapitated. On fresh cryostat sections of the testes of each animal enzymehistochemical reaction for the activity of 3betaHSD was carried out. Our results demonstrate that in sedentary rats ND treatment decreased the activity of 3betaHSD in the LC in comparison to SP. Endurance training also decreased the activity of 3betaHSD in TP group compared to SP. On sections of the testes of group TND a pronounced reduction in the enzyme activities of 3betaHSD in the LC was found in comparison with the other groups. In conclusion we suggest that submaximal endurance training and/or administration of AAS downregulate the steroidogenic enzyme activity of rat Leydig cells.