Seasonal Oxy-Inflammation and Hydration Status in Non-Elite Freeskiing Racer: A Pilot Study by Non-Invasive Analytic Method.

Freeskiing is performed in an extreme environment, with significant physical effort that can induce reactive oxygen species (ROS) generation and dehydration. This study aimed to investigate the evolution of the oxy-inflammation and hydration status during a freeskiing training season with non-invasive methods. Eight trained freeskiers were investigated during a season training: T0 (beginning), T1-T3 (training sessions), and T4 (after the end). Urine and saliva were collected at T0, before (A) and after (B) T1-T3, and at T4. ROS, total antioxidant capacity (TAC), interleukin-6 (IL-6), nitric oxide (NO) derivatives, neopterin, and electrolyte balance changes were investigated. We found significant increases in ROS generation (T1A-B +71%; T2A-B +65%; T3A-B +49%; p < 0.05-0.01) and IL-6 (T2A-B +112%; T3A-B +133%; p < 0.01). We did not observe significant variation of TAC and NOx after training sessions. Furthermore, ROS and IL-6 showed statistically significant differences between T0 and T4 (ROS +48%, IL-6 +86%; p < 0.05). Freeskiing induced an increase in ROS production, which can be contained by antioxidant defense activation, and in IL-6, as a consequence of physical activity and skeletal muscular contraction. We did not find deep changes in electrolytes balance, likely because all freeskiers were well-trained and very experienced.

Enhanced-Precision Measurement of Glutathionyl Hemoglobin by MALDI-ToF MS.

Glutathionyl-hemoglobin (HbSSG) is used as a human biomarker to pinpoint systemic oxidative stress caused by various pathological conditions, noxious lifestyles, and exposure to drugs and environmental or workplace toxicants. Measurement by MALDI mass spectrometry is most frequently used, however, the method suffers from excessive uncontrolled variability. This article describes the improvement of a MALDI-ToF mass spectrometry method for HbSSG measurement through enhanced precision, based on strict control of sample preparation steps and spreadsheet-based data analysis. This improved method displays enhanced precision in the analysis of several hundred samples deriving from studies in different classes of healthy and diseased human subjects. Levels span from 0.5% (lower limit of detection) up to 30%, measured with a precision (as SE%) < 0.5%. We optimized this global procedure to improve data quality and to enable the Operator to work with a reduced physical and psychological strain. Application of this method, for which full instruction and the data analysis spreadsheet are supplied, can encourage the exploitation of HbSSG to study human oxidative stress in a variety of pathological and living conditions and to rationally test the efficacy of antioxidant measures and treatments in the frame of health promotion.

Serum Amino Acid Profile Changes After Repetitive Breath-Hold Dives: A Preliminary Study.

BACKGROUND: The aim of this work was to investigate the serum amino acid (AA) changes after a breath-hold diving (BH-diving) training session under several aspects including energy need, fatigue tolerance, nitric oxide (NO) production, antioxidant synthesis and hypoxia adaptation. Twelve trained BH-divers were investigated during an open sea training session and sampled for blood 30 min before the training session, 30 min and 4 h after the training session. Serum samples were assayed for AA changes related to energy request (alanine, histidine, isoleucine, leucine, lysine, methionine, proline threonine, valine), fatigue tolerance (ornithine, phenylalanine, tyrosine), nitric oxide production (citrulline), antioxidant synthesis (cystine, glutamate, glycine) and hypoxia adaptation (serine, taurine). MAIN RESULTS: Concerning the AA used as an energy support during physical effort, we found statistically significant decreases for all the investigated AA at T1 and a gradual return to the basal value at T2 even if alanine, proline and theonine still showed a slight significant reduction at this time. Also, the changes related to the AA involved in tolerance to physical effort showed a statistically significant decrease only at T1 respect to pre-diving value and a returned to normal value at T2. Citrulline, involved in NO production, showed a clear significant reduction both at T1 and T2. Concerning AA involved in endogenous antioxidant synthesis, the behaviour of the three AA investigated is different: we found a statistically significant increase in cystine both at T1 and T2, while glycine showed a statistically significant reduction (T1 and T2). Glutamate did not show any statistical difference. Finally, we found a statistically significant decrease in the AA investigated in other hypoxia conditions serine and taurine (T1 and T2). CONCLUSIONS: Our data seem to indicate that the energetic metabolic request is in large part supported by AA used as substrate for fuel metabolism and that also fatigue tolerance, NO production and antioxidant synthesis are supported by AA. Finally, there are interesting data related to the hypoxia stimulus that indirectly may confirm that the muscle apparatus works under strong exposure conditions notwithstanding the very short/low intensity of exercise, due to the intermittent hypoxia caused by repetitive diving.

White Blood Cells, Platelets, Red Blood Cells and Gas Bubbles in SCUBA Diving: Is There a Relationship?

(1) Background: SCUBA diving can influence changes of several hematological parameters (HP) but the changes of HP in the decompression phases are still unclear. The aim of this study was to investigate any possible relationship between HP and predisposition to inert gas bubble formation after a single recreational dive. (2) Methods: Blood, obtained from 32 expert SCUBA divers, was tested for differences in white blood cells (WBC), granulocytes (GRAN), lymphocytes (LYM), and monocytes (MONO), red blood cells (RBC), and platelets (PLT) between bubblers (B) and non-bubblers (NB). (3) Results: We found inter-subject differences in bubble formation (considering the same diving profile performed by the divers) and a statistically significant higher number of total WBC, GRAN and LYM in NB as compared to the B divers in the pre and in the post diving sample, while no statistical differences were found for MONO and PLT. In addition, we did not find any statistically significant difference between NB and B in RBC. (4) Conclusions: Our results, even if in absence of investigated anti-inflammatory markers, could indicate a relationship between low WBC numbers and bubble formation. This aspect may explain a possible cause of inter-subject differences in bubble formation in divers performing the same dive profile.

Evaluation of the radical scavenging activity of some representative isoprenoid and aromatic cytokinin ribosides (N6-substituted adenosines) by in vitro chemical assays.

Cytokinins are naturally occurring adenine derivatives whose physiological role is that of growth regulators in plants and that show also many other activities either in plants and in mammalian cells. In plants, they can be found mainly as free bases ((N6-substituted adenines, CKs), but also as the corresponding N9- ribosides (N6-substituted adenosines, CKRs). In mammalian cells, CKRs are, in general, more active than CKs. In order to evaluate the intrinsic in vitro antioxidant capacity of some significant CKRs, their scavenging activity against synthetic radicals that are at the basis of well-established antioxidant assays (ORAC, TEAC, DPPH) has been evaluated. The results of the in vitro scavenging activity of biologically relevant radicals such as hydroxyl (HO•), superoxide (O2.-) and lipid peroxides (R-OO.) are reported and discussed.

Hyperoxia and oxidative stress in anesthesia and critical care medicine.

Oxygen administration is particularly relevant in patients undergoing surgery under general anesthesia and in those who suffer from acute or critical illness. Nevertheless, excess O2, or hyperoxia, is also known to be harmful. Toxicity arises from the enhanced formation of reactive oxygen species (ROS) that, exceeding the antioxidant defense, may generate oxidative stress. Oxidative stress markers are used to quantify ROS toxicity in clinical and non-clinical settings and represent a promising tool to assess the optimal FiO2 in anesthesia and critical care setting. Despite controversial, the guidelines for the regulation of FiO2 in such settings suggest the adoption of high perioperative oxygen levels. However, hyperoxia has also been shown to be an independent mortality risk factor in critically ill patients. In this literature review, we discuss the biochemical mechanisms behind oxidative stress and the available biomarkers for assessing the pro-oxidant vs antioxidant status. Then, we summarize recent knowledge on the hyperoxia-related consequences in the most common anesthesia and critical care settings, such as traumatic brain injury or cardiac arrest. To this purpose, we searched the PubMed database according to the following combination of key words: ("hyperoxia" OR "FiO2" OR "oxygen therapy") AND ("oxidative stress" OR "ROS" OR "RNS" OR "lipid peroxidation") AND ("anesthesia" OR "surgery" OR "intensive care"). We focused in the results from the past 20 years. Available evidence points toward a conservative monitoring and use of oxygen, unless there is solid proof of its efficacy.

Inhibitors of ceramide de novo biosynthesis rescue damages induced by cigarette smoke in airways epithelia.

Exposure to cigarette smoke represents the most important risk factor for the development of chronic obstructive pulmonary disease (COPD). COPD is characterized by chronic inflammation of the airways, imbalance of proteolytic activity resulting in the destruction of lung parenchyma, alveolar hypoxia, oxidative stress, and apoptosis. Sphingolipids are structural membrane components whose metabolism is altered during stress. Known as apoptosis and inflammation inducer, the sphingolipid ceramide was found to accumulate in COPD airways and its plasma concentration increased as well. The present study investigates the role of sphingolipids in the cigarette smoke-induced damage of human airway epithelial cells. Lung epithelial cells were pre-treated with sphingolipid synthesis inhibitors (myriocin or XM462) and then exposed to a mixture of nicotine, acrolein, formaldehyde, and acetaldehyde, the major toxic cigarette smoke components. The inflammatory and proteolytic responses were investigated by analysis of the mRNA expression (RT-PCR) of cytokines IL-1ß and IL-8, and matrix metalloproteinase-9 and of the protein expression (ELISA) of IL-8. Ceramide intracellular amounts were measured by LC-MS technique. Ferric-reducing antioxidant power test and superoxide anion radical scavenging activity assay were used to assess the antioxidant power of the inhibitors of ceramide synthesis. We here show that ceramide synthesis is enhanced under treatment with a cigarette smoke mixture correlating with increased expression of inflammatory cytokines and matrix metalloproteinase 9. The use of inhibitors of ceramide synthesis protected from smoke induced damages such as inflammation, oxidative stress, and proteolytic imbalance in airways epithelia.

Natural grape extracts regulate colon cancer cells malignancy.

Natural dietary components are evolutionary-selected molecules able to control inflammation and cancerous transformation and progression. Because many studies assessed the beneficial properties of key molecules extracted from grapes, we aimed at investigating the properties of Liofenol™, a natural red wine lyophilized extract, devoid of alcohol and composed by a miscellaneous of components (polyphenols, flavonoids, anthocyanins). We proved that the colon cancer cell line HCT116 responded to Liofenol™ treatment by reducing their proliferation, in association with an increase of p53 and p21 cell cycle gate keepers. Liofenol™ increased dihydroceramides, sphingolipid mediators involved in cell cycle arrest and reduced proliferation rate. We observed a strong induction of antioxidant response, with the activation of the transcriptional factor Nrf2, involved in redox homeostasis and differentiation, without altering tumor sensitivity to chemotherapy. Liofenol™ induced an important morphology change in HCT116 cells, migration inhibition, undifferentiated stem/stem-like cells markers downregulation, and E-cadherin downregulation, interested in epithelia to mesenchymal malignant transition. We conclude that lyophilized grape extract, at dose comparable to putative dietary doses, can activate molecular pathways, involving Nrf2 signaling and the modulation of structural and signaling sphingolipid mediators that cooperate in promoting differentiation and reducing proliferation of digestive tract cancer cells.

Naturally occurring N(6)-substituted adenosines (cytokinin ribosides) are in vitro inhibitors of platelet aggregation: an in silico evaluation of their interaction with the P2Y(12) receptor.

A few naturally occurring N(6)-substituted adenosine derivatives (cytokinin ribosides) were investigated as inhibitors of platelet aggregation induced in vitro by collagen and their activity range was demonstrated (IC50: 6.77-141 µM). A docking study suggests that anti-aggregation activity of these compounds could involve an interaction with the P2Y12 receptor binding site.