Alterations in Red Blood Cells and Plasma Properties after Acute Single Bout of Exercise

The aim of this study was to investigate alterations in haemoglobin conformation and parameters related to oxidative stress in whole erythrocytes, membranes, and plasma after a single bout of exercise in a group of young untrained men. Venous blood samples from eleven healthy young untrained males (age = 22 ± 2 years, BMI = 23 ± 2.5 kg/m2) were taken from the antecubital vein before an incremental cycling exercise test, immediately after exercise, and 1 hour after exercise. Individual heart rate response to this exercise was 195 ± 12 beats/min and the maximum wattage was 292 ± 27 W. Immediately after exercise, significant increase in standard parameters (haemoglobin, haematocrit, lactate levels, and plasma volume) of blood was observed as well as plasma antioxidant capacity one hour after exercise. Reversible conformational changes in haemoglobin, measured using a maleimide spin label, were found immediately following exercise. The concentration of ascorbic acid inside erythrocytes significantly decreased after exercise. A significant decline in membrane thiols was observed one hour after exercise, but simultaneously an increase in plasma thiols immediately after and 1 h after exercise was also observed. This study shows that a single bout of exercise can lead to mobilization of defensive antioxidant systems in blood against oxidative stress in young untrained men

Differing Effects of Younger and Older Human Plasma on C2C12 Myocytes in Vitro

Ageing is associated with a general reduction of physiological function and a reduction of muscle mass and strength. Endocrine factors such as myostatin, activin A, growth and differentiation factor 11 (GDF-11) and their inhibitory peptides influence muscle mass in health and disease. We hypothesised that myocytes cultured in plasma from older and younger individuals would show an ageing effect, with reduced proliferation and differentiation in older environments. C2C12 myoblasts were grown as standard and stimulated with media conditioned with 5% plasma from healthy male participants that were either younger (n = 6, 18–35 years of age) or older (n = 6, >57 years of age). Concentration of plasma myostatin (total and free), follistatin-like binding protein (FLRG), GDF-11 and activin A were quantified by ELISA. Both FLRG and activin A were elevated in older individuals (109.6 and 35.1% increase, respectively), whilst myostatin (free and total) and GDF-11 were not. Results indicated that plasma activin A and FLRG were increased in older vs. younger participants, GDF11 and myostatin did not differ. Myoblasts in vitro showed no difference in proliferation rate between ages, however scratch closure was greater in younger vs. older plasma stimulated myoblasts (78.2 vs. 87.2% of baseline scratch diameter, respectively). Myotube diameters were larger in cells stimulated with younger plasma than with older at 24 and 48 h, but not at 2 h. A significant negative correlation was noted between in vivo plasma FLRG concentration and in vitro myotube diameter 48 h following plasma stimulation (r2 = 0.392, p = 0.030). Here we show that myoblasts and myotubes cultured in media conditioned with plasma from younger or older individuals show an ageing effect, and further this effect moderately correlates with circulating FLRG concentration in vivo. The effect of ageing on muscle function may not be innate to the tissue, but involve a general cellular environment change. Further work is needed to examine the effect of increased FLRG concentration on muscle function in ageing populations

Loss of oxidative defense and potential blockade of satellite cell maturation in the skeletal muscle of patients with cancer but not in the healthy elderly

Purpose: Muscle wasting in old age or cancer may result from failure of myofibre regeneration and /or accelerated apoptosis both of which may be up-regulated by oxidative stress or inflammation. The aim of this study was to determine from the transcriptome in human skeletal muscle whether there is evidence for oxidative stress and its relationship with satellite cell differentiation or apoptosis in the muscle of patients with cancer (weight-stable: CWS or weight-losing: CWL) or healthy elderly (HE) when compared with healthy middle aged controls (HMAC) . Design: 28 patients with resectable upper GI/pancreatic cancer (CWS: 14 and CWL14), 17 HE and 22 HMAC underwent biopsy of the quadriceps muscle. Markers of muscle regeneration, inflammation, oxidative stress and apoptosis were measured by qPCR. Results: The expression of transcription factors responsible for muscle regeneration (Pax3, Pax7 and MyoD) were increased in the skeletal muscle of CWS and HE when compared with HMAC (P<0.001). In contrast, the expression of myogenic differentiation markers (MyoG and Myh2) was reduced in CWS and CWL but increased in HE when compared with HMAC (P<0.0001). The expression of the pro-apoptotic gene Bax was significantly increased in CWS, CWL and HE compared with HMAC (P<0.0001). Pro-inflammatory cytokine expression was variable with increased expression of TNF in CWS and HE, increased Il-6 in CWS and increased Il-1 in CWL when compared with HMAC. Expression of the oxidative defense genes SOD2, GCLM, and NRF2 was decreased in CWS and CWL but increased in HE when compared with HMA (P<0.0001). Conclusion: There is evidence for blockade of satellite cell maturation, upregulation of apoptosis and reduced oxidative defense in the skeletal muscle of cancer patients. In contrast, in muscle from healthy elderly the potential for myotube differentiation and oxidative defense is maintained

Characteristics of stomach diseases

The paper describes different diseases of the human stomach with regard to the activity of Helicobacter pylori associated with them. It is believed that the Helicobacter pylori infection is always connected with damage of the surface of epithelium, which is accompanied by different degrees of inflammation. It was found, that the bacteria plays a crucial role in the patophysiology of most of stomach and duodenum diseases. Helicobacter pylori is most frequently reported to be the cause of stomach inflammations and cancer disease. It is also believed to cause stomach and duodenum ulcers. Helicobacter pylori has been detected in 60-80% of patients with ulcer disease and in about 90-100% patients with duodenum disease. The presence of Helicobacter pylori was observed in 50% of patients with dyspepsia and epigastric pains.Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 dofinansowane zostało ze środków MNiSW w ramach działalności upowszechniającej naukę