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Sarcopenia is a condition of multifaceted etiology arising in many elderly people. In patients with chronic kidney, the loss of muscle mass is much more intensive and the first signs of sarcopenia are observed in younger patients than it is expected. It is associated with the whole-body protein-energy deficiency called protein-energy wasting (PEW). It seems to be one of the major factors limiting patient's autonomy as well as decreasing the quality of life. If it cannot be treated with the simple methods requiring some knowledge and devotion, we will fail to save patients who die due to cardiovascular disease and infection, despite proper conduction of renal replacement therapy. Many factors influencing the risk of sarcopenia development have been evaluated in number of studies. Many studies also were conducted to assess the efficacy of different therapeutic strategies (diet, physical activity, hormones). Nevertheless, there is still no consensus on treatment the patients with PEW. Therefore, in the paper we present the reasons and pathophysiology of sarcopenia as an important element of protein energy wasting (PEW) in elderly patients suffering from chronic kidney disease. We also analyze possible options for treatment according to up-to-date knowledge.

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Organised nanotopography mimicking the natural extracellular matrix can be used to control morphology, cell motility, and differentiation. However, it is still unknown how specifi c cell types react with specifi c patterns. Both initial adhesion and preferential cell migration may be important to initiate and increase cell locomotion and coverage with cells, and thus achieve an enhanced wound healing response around an implantable material. Therefore, the aim of this study was to evaluate how MC3T3-E1 osteoblast initial adhesion and directional migration are infl uenced by nanogrooves with pitches ranging from 150 nm up to 1000 nm. In this study, we used a multipatterned substrate with fi ve different groove patterns and a smooth area with either a concentric or radial orientation. Initial cell adhesion measurements after 10 s were performed using atomic force spectroscopy-assisted single-cell force spectroscopy, and demonstrated that nascent cell adhesion was highly induced by a 600 nm pitch and reduced by a 150 nm pitch. Addition of RGD peptide signifi cantly reduced adhesion, indicating that integrins and cell adhesive proteins (e.g. fi bronectin or vitronectin) are key factors in specifi c cell adhesion on nanogrooved substrates. Also, cell migration was highly dependent on the groove pitch; the highest directional migration parallel to the grooves was observed on a 600 nm pitch, whereas a 150 nm pitch restrained directional cell migration. From this study, we conclude that grooves with a pitch of 600 nm may be favourable to enhance fast wound closure, thereby promoting tissue regeneration.

The incidence and diagnosis of chronic kidney disease (CKD) is on the rise all over the world. CKD is related to ageing of the society and high morbidity due to lifestyle diseases like diabetes, atherosclerosis, and hypertension. CKD is associated with increased oxidative stress generated by uremic toxicity, chronic inflammatory state, lack of vitamins and microelements, parenteral iron administration, and dialysis procedure itself. In terms of cellular physiology, erythrocytes and blood platelets in particular have effective enzymatic and non-enzymatic antioxidative system. The most efficient enzymatic antioxidants include superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase. Glutathione is the leading non-enzymatic free radical scavenger. In CKD, antioxidative defense is impaired and the abnormal activity of the enzymes and glutathione concentration is described in literature. The imbalance between the formation of reactive oxygen species and antioxidative system efficiency takes part in the pathogenesis of cardiovascular complications. It contributes to increased morbidity and mortality in patients with CKD. The severity of these processes depends on the type of renal replacement therapy; haemodialysis (HD) is more predisposing to such disorders than peritoneal dialysis (PD), or even conservative treatment. This can influence the outcome and the possibility of kidney transplantation. Moreover, the early function of kidney allograft seems to be dependent on perioperative antioxidative ability of platelets, which can play a potential protective role in kidney transplantation.