Introduction: Antimicrobial peptides (AMP) are a large group of innate immune effectors, which apart from antimicrobial activity show immunomodulative properties. Platelet-rich plasma (PRP) is a source of autologous growth factors and is used for stimulation of bone and soft tissue healing. The purpose of this study was to assess the influence of PRP and AMP extract on ovine monocyte-derived macrophage cultures. Material and Methods: The study was conducted on ovine macrophages (Mfs) previously stimulated with LPS or dexamethasone and then with preparations of PRP or AMP. Following activation of the Mfs their morphological and functional features were assessed. Results: The study revealed pro-inflammatory influence of both examined preparations on Mfs cultures on the basis of morphology, ROS generation and arginase activity. Both preparations enhanced the pro-inflammatory response of cultured Mfs. Conclusion: This activity may intensify the antimicrobial action of Mfs, however, in cases of excessive and prolonged inflammation the use of these preparations should be limited.

For many years, scientists have been pursuing research on skeletal muscle ageing both in humans and animals. Studies on animal models have extended our knowledge of this mechanism in humans. Most researchers agree that the major processes of muscle ageing occur in the mitochondria as the major energy production centres in muscle cells. It is believed that decisive changes occur at the enzymatic activity level as well as in protein synthesis and turnover ability. Deregulation of ion channels and oxidative stress also play significant roles. In particular, in recent years the free radical theory of ageing has undergone considerable modification; researchers are increasingly highlighting the partly positive effects of free radicals on processes occurring in cells. In addition, the influence of diet and physical activity on the rate of muscle cell ageing is widely debated as well as the possibility of delaying it through appropriate physical exercise and diet programmes. Numerous studies, especially those related to genetic processes, are still being conducted, and in the near future the findings could provide valuable information on muscle ageing. The results of ongoing research could answer the perennial question of whether and how we can influence the rate of ageing both in animals and humans.

Introduction: Peroxiredoxin 6 (Prdx6) is a bifunctional protein with glutathione peroxidase activity and phospholipase A2 activity. Previous studies have shown a significant positive correlation between the intracellular survival ability of Brucella and Prdx6. Here, the Prdx6 enzyme with a single activity was constructed to facilitate study of the relationship between the single function of Prdx6 and Brucella infection. Material and Methods: The target open reading frame (ORF) DNAs of Prdx6 with a single active centre were prepared using gene splicing by overlap extension PCR (SOE-PCR), and the recombinant eukaryotic expression plasmids inserted by Prdx6 with the single activity centre were constructed and transfected into murine Raw264.7 macrophages. The glutathione peroxidase activity and phospholipase A2 activity of the constructed Prdx6 were examined. Results: The core centres (Ser³² and Cys⁴⁷) of Prdx6 were successfully mutated by changing the 94ᵗʰ nucleotide from T to G and the 140ᵗʰ nucleotide from G to C in the two enzyme activity cores, respectively. The constructed recombinant plasmids of Prdx6 with the single active centre were transfected into murine macrophages showing the expected single functional enzyme activity, which MJ33 or mercaptosuccinate inhibitors were able to inhibit. Conclusion: The constructed mutants of Prdx6 with the single activity cores will be a benefit to further study of the biological function of Prdx6 with different enzyme activity.

The aim of this study was to evaluate potential protective effects of propolis on furan-induced hepatic damage by assessing the levels of malondialdehyde (MDA) and reduced glutathione (GSH), antioxidant enzyme activities, and histopathological changes in the liver. Albino Wistar rats were divided into six groups: a control, propolis-treated (100 mg/kg b.w./day), low-dose furan-treated (furan-L group; 2 mg/kg b.w./day), high-dose furan-treated (furan-H group; 16 mg/kg b.w./day), furan-L+propolis treated, and furan-H+propolis treated group. Propolis and furan were applied by gavage; propolis for 8 days, and furan for 20 days in furan-L groups and 10 days in furan-H groups. While MDA levels were elevated in furan-treated groups, levels of GSH and activities of antioxidant enzymes decreased (p < 0.001). The levels of MDA and GSH and activities of antioxidant enzymes were normal in the furan+propolis groups, especially in the furan-L+propolis group (p < 0.001). While the aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate pdehydrogenase activities were elevated in the furan-H treated group (p < 0.05 and p < 0.001), they were unchanged in the furan-L treated group. Histopathologically, several lesions were observed in the liver tissues of the furan-treated groups, especially in the higher-dose group. It was determined that these changes were milder in both of the furan+propolis groups. The results indicate that propolis exhibits good hepatoprotective and antioxidant potential against furan-induced hepatocellular damage in rats.