Short-term effects of continuous positive airway pressure on oxidative stress in severe sleep apnea

Sleep and Breathing - Obstructive sleep apnea (OSA) is associated with oxidative stress that is involved in the pathogenesis of cardiovascular and metabolic complications. The concentrations of...     

Effects of testosterone and estradiol on anxiety and depressive-like behavior via a non-genomic pathway

Besides their known slow genomic effects, testosterone and estradiol have rapid effects in the brain. However, their impact on mood-related behavior is not clear. The aim of this study was to investigate the non-genomic pathway of testosterone and estradiol in the amygdala in relation to anxiety and depressive-like behavior. Sham-operated and gonadectomized male rats(GDX) supplemented with testosterone propionate, estradiol, or olive oil were used. Five minutes after administration, anxiety and depression-like behavior were tested. Estradiol increased anxiolytic behavior in the open-field test compared to the GDX group, but administration of testosterone had no significant effect. Besides, c-Fos expression in the medial nucleus of the amygdala significantly increased after testosterone treatment compared to the GDX group, while no significant difference was observed in the central and the basolateral nuclei of the amygdala in the testosterone-treated group compared to the GDX group. In conclusion, estradiol had an anxiolytic effect via a rapid pathway, but no rapid effect of testosterone on anxiety was found. Further studies elucidating whether the rapid effect is mediated by a non-genomic pathway are needed.     

Short‐term effects of continuous positive airway pressure on sex hormones in men and women with sleep apnoea syndrome

Patients with sleep apnoea syndrome (SAS) suffer from symptoms of hypogonadism. Besides surgical interventions, in some cases, the standard care of SAS for most patients is continuous positive airway pressure (CPAP). Studies focusing on the long‐term effects of CPAP on testosterone levels revealed conflicting results. None of the studies included female patients with SAS. The aim of our study was to analyse and compare sex hormone levels in saliva before and after a night without and with CPAP in women and men with SAS. The results were negative. One night with CPAP did not affect the dynamics of sex hormones, neither in men nor in women. Future studies should focus on long‐term effects of CPAP in both genders.     

Massive localized lymphedema: a reactive lesion simulating liposarcoma (case report

The authors present a case-history of massive localized lymphedema in a 54 year old female patient (height 167 cm, weight 113 kg). The history of the lymphedema lasted about 1 year. Its growth was not accompained with subjective complaints. It was diagnosed as a pendulous tumor of soft tissues in the thigh, 70 x 65 cm large. In preoperative diagnosis it was classified as a liposarcoma. The tumor lesion was removed and sent for bioptic examinations. Both histological and immunohistochemical biopsies denied benign or malignant nature of the soft tissue tumors and confirmed the diagnosis of a massive localized lymphedema.     

Massives lokalisiertes Lymphödem einer extrem fettleibigen Patientin

Soft tissue tumors are commonly encountered in all surgical departments. The authors present a case of a very rare large tumor lesion, with macroscopic signs of liposarcoma.     

Association between systemic lupus erythematosus and insertion/deletion polymorphism of the angiotensin converting enzyme (ACE) gene.

OBJECTIVE: ACE takes part in the renin-angiotensin and kallikrein-kininogen systems by creating angiotensin-II and inactivating bradykinin. ACE gene insertion/deletion polymorphism is associated with the level of circulating enzymes--subjects with the DD genotype have higher levels of circulating ACE than subjects with the II genotype and show an increased tendency towards impaired vascular function and structure. Patients with systemic lupus erythematosus (SLE) suffer from differentially expressed vascular pathology. We attempted to determine whether the type of ACE polymorphism could contribute to this pathology. METHODS: 101 SLE patients fulfilling the ACR criteria were investigated. The I/D polymorphism was ascertained by PCR, followed by electrophoresis of the amplified fragments and UV visualization. RESULTS: The frequency of the D allele was higher in the SLE group (0.623) than in the controls (0.520) (chi 2 test, p < 0.025). The distribution of the ACE genotype in SLE group was different from that in the control group (p < 0.05). An association between the DD genotype and visceral damage (p < 0.006) was observed. CONCLUSION: Our results suggest that in the multifactorially determined vascular pathology of SLE, changes associated with I/D polymorphism could influence vessel wall inflammation (monocyte adhesion and activation with cytokine release, T-lymphocyte metabolism), a tendency towards vascular impairment (neointimal proliferation, vasospasm, platelet activation, myocyte proliferation) and lead to the subsequent ischemia. The ACE gene could serve as the visceral damage indicator in SLE.     

Prenatal dietary load of Maillard reaction products combined with postnatal Coca-Cola drinking affects metabolic status of female Wistar rats

Aim

To assess the impact of prenatal exposure to Maillard reaction products (MRPs) -rich diet and postnatal Coca-Cola consumption on metabolic status of female rats. Diet rich in MRPs and consumption of saccharose/fructose sweetened soft drinks is presumed to impose increased risk of development of cardiometabolic afflictions, such as obesity or insulin resistance.

Methods

At the first day of pregnancy, 9 female Wistar rats were randomized into two groups, pair-fed either with standard rat chow (MRP-) or MRPs-rich diet (MRP+). Offspring from each group of mothers was divided into two groups and given either water (Cola-) or Coca-Cola (Cola+) for drinking ad libitum for 18 days. Oral glucose tolerance test was performed, and circulating markers of inflammation, oxidative stress, glucose and lipid metabolism were assessed.

Results

MRP+ groups had higher weight gain, significantly so in the MRP+/Cola- vs MRP-/Cola-. Both prenatal and postnatal intervention increased carboxymethyllysine levels and semicarbazide-sensitive amine oxidase activity, both significantly higher in MRP+/Cola + than in MRP-/Cola-. Total antioxidant capacity was lower in MRP+ groups, with significant decrease in MRP+/Cola + vs MRP-/Cola+. Rats drinking Coca-Cola had higher insulin, homeostatic model assessment of insulin resistance, heart rate, advanced oxidation of protein products, triacylglycerols, and oxidative stress markers measured as thiobarbituric acid reactive substances compared to rats drinking water, with no visible effect of MRPs-rich diet.

Conclusion

Metabolic status of rats was affected both by prenatal and postnatal dietary intervention. Our results suggest that combined effect of prenatal MRPs load and postnatal Coca-Cola drinking may play a role in development of metabolic disorders in later life.Maillard reaction products (MRPs), first described by French biochemist C. Maillard in the beginning of 20th century (1), are formed by nonenzymatic reactions of reactive sugars and proteins, giving thermally processed food its typical color, taste, and odor.Eight decades later Brownlee et al. recognized that same substances are formed naturally in human body, and named the in vivo analogues of MRPs “advanced glycation end products” (AGEs) (2,3). Except for classical pathway of their formation under hyperglycemic conditions, there are alternative pathways of AGEs formation effective – under oxidative- and carbonyl-stress, utilizing reactive aldehydes formed during lipid peroxidation and autooxidation of glucose. AGEs are implicated in pathophysiology of aging and different non-communicable diseases: AGE-modification alters the structure (physical and chemical properties) and thus function (biological properties) of proteins (4). Discovery of specific cell-surface receptor for AGEs (RAGE) enabled characterization of indirect harmful pathways leading to enhanced oxidative stress and pro-inflammatory, diabetogenic, and atherogenic effects (5,6).In 1997, Koschinsky et al (7) showed that dietary MRPs partially absorbed into the bloodstream were chemically and biologically active, exerting harmful health effects, which is why they were called “glycotoxins.” This finding prompted extensive research confirming that consumption of large amounts of dietary MRPs might induce or aggravate insulin resistance, renal impairment or atherosclerosis, activate inflammatory and oxidative stress pathways, and contribute to development of complications in diabetes and nephropathies (8-11). These findings raise the question on the role of MRPs-rich diet in prenatal programming. Evidence strongly suggests that maternal obesity and improper prenatal nutrition provide maladaptive intrauterine cues to developing offspring, predisposing organs for chronic disease later in life (12,13). Maternal dietary habits affect the fetus, outcome of pregnancy, and long term health of the child (14-16). Mericq et al found a direct relationship between newborn’s and maternal serum levels of several AGEs at the time of delivery, suggesting maternal transmission of AGEs (17). AGEs/RAGE axis activates in pregnancy-associated pathologies impacting fetus development, such as preeclampsia and preterm birth (18-20).Rising prevalence of obesity and obesity-associated (particularly metabolic) complications in youth (21,22) was linked, among others, to rising consumption of sugar-sweetened carbonated drinks such as cola beverages (23,24). Effects are attributed to multiple factors, including higher caloric intake, high fructose content rendering less satiety and compensation and resulting in elevated plasma uric acid, and a general effect of consuming refined carbohydrates (25,26). Moreover, cola beverages also contain MRPs and reactive AGE-precursors, most abundantly hydroimidazolone derived from arginine residues modified by methylglyoxal (27,28).To the best of our knowledge potential effects of MRPs-rich diet during pregnancy on prenatal programming have yet not been investigated. In this study we investigated the metabolic status of young adult rats – offspring of mothers consuming MRPs-rich diet during pregnancy. As drinking of cola beverages is increasingly popular among children and adolescents, our second aim was to investigate the additional impact of Coca-Cola consumption on prenatally affected young adult rats.     

Oxidative stress and electron spin resonance

The body constantly reacts with oxygen as part of the energy producing processes of cells. Oxidative stress is a dysbalance between the production of free radicals as products of these reactions and antioxidant properties of cells. The factors influencing the production of free radicals are physical agents, chemical agents and biological agents. Free radicals are paramagnetic molecules with short time-period for their detection by electron spin resonance (ESR) spectroscopy. The free radical stabilization can be gained by freezing a solution of an organic radical or bonding to spin trapping agents. The spin trapping agents are diamagnetic compounds which rapidly scavenge transient radicals to form stable paramagnetic spin adducts radicals. Because this secondary radical retains an unpaired electron, it can often be detected by electron spin resonance. From ESR spectra can be obtained structural information and kinetic information, information about the formation and decay of the radicals. To study the process of free radical generation is an important step towards reducing the deteriorating effects of oxidative stress.     

Physical activity induces depression-like behavior in intact male rats

Testosterone affects behavior. Whether regular physical training does influence these effects is unknown. The assumption that testosterone induces muscular hypertrophy if combined with physical training has not been confirmed experimentally. The aim of this study was to evaluate whether activity and/or testosterone treatment affects depression-like behavior and to observe the effects of activity and testosterone on muscle fiber diameter.Forty-three male rats were divided into 4 groups: two groups (TST act and TST lazy) were treated with testosterone (5 mg/kg) and two groups were used as control (CTRL act and CTRL lazy). Two of the groups (CTRL act and TST act) underwent 2 weeks of exercise. The forced swim test was used as a test of depression-like behavior. Sex steroids were measured and the diameter of skeletal muscle fibers was evaluated.Testosterone was significantly higher in both testosterone-treated groups (p < 0.001). Physically active groups had higher immobility times in the forced swim test than inactive groups. Groups CTRL act and TST lazy showed significantly larger diameter of muscle fibers in comparison to the TST act group.Our results suggest that physical activity induces depression-like behavior in rats. Controversial antagonistic effects of testosterone and physical activity on muscle fiber diameter were found.