Discovery and Characterization of an Endogenous CXCR4 Antagonist

CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPIX4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation

Mineral content of menus offered by social welfare home

Background: The aging of the population in Poland and globally has increased interest in nutrition for the elderly. Their diets are inappropriate, but modifications should be introduced gradually. This is important in hospital settings, sanatoriums or social care homes, where patients have few choices. Aim of the study: The study aimed to assess the content of the selected mineral salts in ten day menus offered by the Social Welfare Home based on season of the year. Material and methods: The study included 40 menus offered in four seasons of the year for the residents of the Social Welfare Home in Lower Silesia. The mineral content of the foods on the menus were assessed. We considered the physical activity of the elderly (1.4—Physical Activity Level) using norms developed by the Food and Nutrition Institute, and calculated the average norms of the analysed nutrients for people over 60 years of age. Results: The diets were low in minerals such as calcium and potassium, and contained an excessive amount of phosphorus, sodium, iron and zinc in all seasons. Although magnesium levels in the spring and summer were appropriate, deficits appeared in autumn and winter diets. Conclusions: The evaluated menus showed inadequate supplies of the assessed mineral salts. More analysis and adjustments to planned meals is recommended

Discovery and Characterization of an Endogenous CXCR4 Antagonist

CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation