Background: A comparison of the amino acid (AA) plasma profile and markers of intestinal absorption-inflammation between healthy subjects aged 65-70 years and age-matched patients affected by stage 3b-4 chronic kidney disease (CKD3b-4) was performed. Methods: eleven healthy volunteers were compared with 12 CKD3b-4 patients at their first outpatient control (T0) and after 12-months (T12). Adherence to a low protein diet (LPD, 0.6±0.1 g/kg/day) was assessed by Urea Nitrogen Appearance. The following parameters were assessed: renal function, nutritional parameters, bioelectrical impedance analysis, plasma levels of 20 total aminoacids (TAAs), both essential (EAAs) including branched-chain amino acids (BCAAs) and non-essential (NEAAs). Zonulin and faecal Calprotectin markers were used to evaluate intestinal permeability/inflammation. Results: Four patients dropped out of the study; in the remaining 8 residual kidney function (RKF) remained stable, their LPD adherence had risen to 0.89g/kg/day, anaemia had worsened and extracellular body fluid had increased. In comparison to healthy subjects, TAA levels of histidine, arginine, asparagine, threonine, glycine, and glutamine had all increased. No variation in BCAAs was observed. A significant increase was detected in faecal calprotectin and zonulin levels in CKD patients as the disease progressed. Conclusions: This study confirms the finding in aged patients of an alteration in levels of several AAs secondary to uraemia. Intestinal markers provide confirmation of a relevant alteration to the intestinal function in CKD patients.

Chronic diseases are characterised by cell’s autophagy and proteins disarrangement resulting in sarcopenia, hypoalbuminemia and hypo-haemoglobinaemia. Hypo-haemoglobinaemia couses worse prognosis independentely of the principal disease. Currently, the cornerstone of therapy of anaemia is iron supplementation, with or without erythropoietin for the stimulation of hematopoiesis. However, treatment strategies should incorporate the addition of heme, the principal biochemical constituent of haemoglobin. Heme synthesis follows a complex biochemical pathway. The limiting step of heme synthesis is D-ALA availability which, for its synthesis, requires Glycine and Succinil-CoA. Consequently, treatment of anaemia should not be based only on iron availability, but also on the availability of the molecules fundamental for heme synthesis. Therefore, an adequate clinical therapeutic strategy should integrate the standard iron infusion and the supply of essential amino acids and vitamins involved in the heme synthesis. We report preliminary data in selected elderly anaemic patients with congestive heart failure (CHF) and catabolic disarrangement, who, in addition to standard iron therapy, received personalized therapy with essential-AAs and vitamins involved in the maintenance of heme. Notably, such individualized therapy resulted in a significant increase in the serum concentration of haemoglobin after 30 days of treatment compared to standard iron therapy.

Graviera is a very popular yellow hard cheese produced in mainland Greece and the Aegean islands, and in three PDO (Protected Denomination of Origin) locations. Apart from geographic location, milk type and production practices are also factors that affect cheese composition, and make this dairy product unique in taste and aroma. In this work, 1H NMR spectroscopy in combination with chemometrics has been used to determine the metabolite profile (40 compounds) of graviera cheese produced in different geographic locations, with emphasis on cheeses produced on the island of Crete. Organic acids and amino acids were the main components quantified in the polar cheese fraction, while the fatty acid composition of the lipid fraction was also obtained. Analysis of Variance (Anova) of the dataset showed that γ-aminobutyric acid (GABA), conjugated linoleic acids (CLA) and linoleic acid differentiate gravieras produced in different areas of Crete, and that total amino acid content was higher in cheeses produced in eastern Crete. Targeted Discriminant Analysis models classified gravieras produced in mainland Greece, Cyclades and Crete based on differences in 1,2-diglycerides, sterols, GABA and fatty acid composition. Targeted and untargeted OPLS-DA models were capable of differentiating between gravieras produced in the island of Crete and hold promise as the basis for the authentication of PDO graviera products.