The Influence of N-Acetyl-selenomethionine on Two RONS-Generating Cancer Cell Lines Compared to N-Acetyl-methionine.

N-acetyl-selenomethionine (NASeLM), a representative of the selenium compounds, failed to convince in clinical studies and cell cultures that it neither inhibits cancer growth nor has a chemoprotective effect. This study aims to find out whether NASeLM shows a growth-inhibiting property compared to the carrier substance N-Acetyl-L-methionine (NALM) on two different cancer cells, namely Jurkat cells and MTC-SK cells. METHODS: Jurkat and MTC-SK cells were cultured in the absence or presence of varying concentrations (0-500 µg/mL) of NASeLM and NALM solutions. After 0, 24, 48, and 72 h, mitochondrial activity, cancer cell membrane CP levels, cell growth, and caspase-3 activity were assessed in aliquots of Jurkat and MTC-SK cells. RESULTS: Both substances, NASeLM and NALM, were similarly able to inhibit cell growth and mitochondrial activity of Jurkat cells in a concentration-dependent and time-dependent manner up to 70%. Only the determination of caspase activity showed that only NASeLM was able to increase this to almost 40% compared to the control as well as the same lack of NALM. However, the experiments on MTC-SK cells showed a clear difference in favor of NASeLM compared to NALM. While NASeLM was able to reduce cell growth to up to 55%, the same amount of NALM was only at around 15%, which turned out to be highly significant (p < 0.001). The same could also be measured for the reduction in MTC-SK mitochondrial activity. Time dependence could also be recognized: the longer both substances, NASeLM and NALM, were incubated, the higher the effect on cell growth and mitochondrial activity, in favour of NASeLM. Only NASeLM was able to increase caspase-3 activity in MTC-SK cells: at 250 µg/mL NASeLM, caspase-3 activity increased significantly to 28% after 24 and 48 h compared to the control (14%) or the same NALM concentration (14%). After 72 h, this could still increase to 37%. A further increase in the NASeLM concentration did not result in higher caspase-3 activity. CONCLUSION: NASeLM could clearly increase caspase-3 activity in both cell types, Jurkat or MTC-SK cells, and thus induce cell death. NALM and NASeLM showed a reduction in cell growth and mitochondrial activity in both cell lines: While NALM and NASeLM showed almost identical measurements on Jurkat cells, NASeLM was much more effective on MTC-SK than the non-selenium-containing carrier, indicating that it has additional anti-chemoprotective effects.

Different RONS Generation in MTC-SK and NSCL Cells Lead to Varying Antitumoral Effects of Alpha-Ketoglutarate + 5-HMF.

BACKGROUND: Carbonylated proteins (CPs) serve as specific indicators of increased reactive oxygen and nitrogen species (RONS) production in cancer cells, attributed to the dysregulated mitochondrial energy metabolism known as the Warburg effect. The aim of this study was to investigate the potential of alpha-ketoglutarate (aKG), 5-hydroxymethylfurfural (5-HMF), and their combination as mitochondrial-targeting antioxidants in MTC-SK or NCI-H23 cancer cells. METHODS: MTC-SK and NCI-H23 cells were cultured in the absence or presence of varying concentrations (0-500 µg/mL) of aKG, 5-HMF, and the combined aKG + 5-HMF solutions. After 0, 24, 48, and 72 h, mitochondrial activity, cancer cell membrane CP levels, cell growth, and caspase-3 activity were assessed in aliquots of MTC-SK and NCI-H23 cells. RESULTS: The mitochondrial activity of MTC-SK cells exhibited a concentration- and time-dependent reduction upon treatment with aKG, 5-HMF, or the combined aKG + 5-HMF. The half-maximal inhibitory concentration (IC50%) for mitochondrial activity was achieved at 500 µg/mL aKG, 200 µg/mL 5-HMF, and 200 µg/mL aKG + 66.7 µg/mL 5-HMF after 72 h. In contrast, NCI-H23 cells showed a minimal reduction (10%) in mitochondrial activity even at the highest combined concentration of aKG + 5-HMF. The CP levels in MTC-SK cells were measured at 8.7 nmol/mg protein, while NCI-H23 cells exhibited CP levels of 1.4 nmol/mg protein. The combination of aKG + 5-HMF led to a decrease in CP levels specifically in MTC-SK cells. The correlation between mitochondrial activity and CP levels in the presence of different concentrations of combined aKG + 5-HMF in MTC-SK cells demonstrated a linear and concentration-dependent decline in CP levels and mitochondrial activity. Conversely, the effect was less pronounced in NCI-H23 cells. Cell growth of MTC-CK cells was reduced to 60% after 48 h and maintained at 50% after 72 h incubation when treated with 500 µg/mL aKG (IC50%). Addition of 500 µg/mL 5-HMF inhibited cell growth completely regardless of the incubation time. The IC50% for 5-HMF on MTC-CK cell growth was calculated at 375 µg/mL after 24 h incubation and 200 µg/mL 5-HMF after 72 h. MTC-SK cells treated with 500 µg/mL aKG + 167 µg/mL 5-HMF showed no cell growth. The calculated IC50% for the combined substances was 250 µg/mL aKG + 83.3 µg/mL 5-HMF (48 h incubation) and 200 µg/mL aKG + 66.7 µg/mL 5-HMF (72 h incubation). None of the tested concentrations of aKG, 5-HMF, or the combined solution had any effect on NCI-H23 cell growth at any incubation time. Caspase-3 activity increased to 21% in MTC-CK cells in the presence of 500 µg/mL aKG, while an increase to 59.6% was observed using 500 µg/mL 5-HMF. The combination of 500 µg/mL aKG + 167.7 µg/mL 5-HMF resulted in a caspase-3 activity of 55.2%. No caspase-3 activation was observed in NCI-H23 cells when treated with aKG, 5-HMF, or the combined solutions. CONCLUSION: CPs may serve as potential markers for distinguishing between cancer cells regulated by RONS. The combination of aKG + 5-HMF showed induced cell death in high-RONS-generating cancer cells compared to low-RONS-generating cancer cells.

Alpha-Ketoglutarate or 5-HMF: Single Compounds Effectively Eliminate Leukemia Cells via Caspase-3 Apoptosis and Antioxidative Pathways.

BACKGROUND: We recently showed that a combined solution containing alpha-ketoglutarate (aKG) and 5-hydroxymethyl-furfural (5-HMF) has a solid antitumoral effect on the Jurkat cell line due to the fact of its antioxidative, caspase-3 and apoptosis activities, but no negative effect on human fibroblasts was obtained. The question arises how the single compounds, aKG and 5-HMF, affect peroxynitrite (ONOO-) and nitration of tyrosine residues, Jurkat cell proliferation and caspase-activated apoptosis. METHODS: The ONOO- luminol-induced chemiluminescence reaction was used to measure the ONOO- scavenging function of aKG or 5-HMF, and their protection against nitration of tyrosine residues on bovine serum albumin was estimated with the ELISA technique. The Jurkat cell line was cultivated in the absence or presence of aKG or 5-HMF solutions between 0 and 3.5 µM aKG or 0 and 4 µM 5-HMF. Jurkat cells were tested for cell proliferation, mitochondrial activity and caspase-activated apoptosis. RESULTS: aKG showed a concentration-dependent reduction in ONOO-, resulting in a 90% elimination of ONOO- using 200 mM aKG. In addition, 20 and 200 mM 5-HMF were able to reduce ONOO- only by 20%, while lower concentrations of 5-HMF remained stable in the presence of ONOO-. Nitration of tyrosine residues was inhibited 4 fold more effectively with 5-HMF compared to aKG measuring the IC50%. Both substances, aKG and 5-HMF, were shown to cause a reduction in Jurkat cell growth that was dependent on the dose and incubation time. The aKG effectively reduced Jurkat cell growth down to 50% after 48 and 72 h of incubation using the highest concentration of 3.5 µM, and 1, 1.6, 2, 3 and 4 µM 5-HMF inhibited any cell growth within (i) 24 h; 1.6, 2, 3 and 4 µM 5-HMF within 48 h (ii); 2, 3 and 4 µM 5-HMF within 72 h (iii). Furthermore, 4 µM was able to eliminate the starting cell number of 20,000 cells after 48 and 72 h down to 11,233 cells. The mitochondrial activity measurements supported the data on aKG or 5-HMF regarding cell growth in Jurkat cells, in both a dose- and incubation-time-dependent manner: the highest concentration of 3.5 µM aKG reduced the mitochondrial activity over 24 h (67.7%), 48 h (57.9%) and 72 h (46.8%) of incubation with Jurkat cells compared to the control incubation without aKG (100%). 5-HMF was more effective compared to aKG; the mitochondrial activity in the presence of 4 µM 5-HMF decreased after 24 h down to 68.4%, after 48 h to 42.9% and after 72 h to 32.0%. Moreover, 1.7 and 3.4 µM aKG had no effect on caspase-3-activated apoptosis (0.58% and 0.56%) in the Jurkat cell line. However, 2 and 4 µM 5-HMF increased the caspase-3-activated apoptosis up to 22.1% and 42.5% compared to the control (2.9%). A combined solution of 1.7 µM aKG + 0.7 µM 5-HMF showed a higher caspase-3-activated apoptosis (15.7%) compared to 1.7 µM aKG or 2 µM 5-HMF alone. In addition, 3.5 µM µg/mL aKG + 1.7 µM 5-HMF induced caspase-activated apoptosis up to 55.6% compared to 4.5% or 35.6% caspase-3 activity using 3.5 µM aKG or 4 µM 5-HMF. CONCLUSION: Both substances showed high antioxidative potential in eliminating either peroxynitrite or nitration of tyrosine residues, which results in a better inhibition of cell growth and mitochondrial activity of 5-HMF compared to aKG. However, caspase-3-activated apoptosis measurements revealed that the combination of both substances synergistically is the most effective compared to single compounds.

Vitamin D-Dimer: A Possible Biomolecule Modulator in Cytotoxic and Phagocytosis Processes?

Background: Vitamin D3 complexed to deglycosylated vitamin D binding protein (VitD-dgVDBP) is a water-soluble vitamin D dimeric compound (VitD-dgVDBP). It is not clear how VitD-dgVDBP affects circulating monocytes, macrophages, other immune cell systems, including phagocytosis and apoptosis, and the generation of reactive oxygen species (ROS) compared to dgVDBP. Methods: Flow cytometry was used to measure superoxide anion radical (O2*−) levels and macrophage activity in the presence of VitD-dgVDBP or dgVDBP. VitD-dgVDBP was incubated with normal human lymphocytes (nPBMCs), and several clusters of determination (CDs) were estimated. dgVDBP and VitD-dgVDBP apoptosis was estimated on malignant prostatic cells. Results: The macrophage activity was 2.8-fold higher using VitD-dgVDBP (19.8·106 counts) compared to dgVDBP (7.0·106 counts), but O2*− production was 1.8-fold lower in favor of VitD-dgVDBP (355·103 counts) compared to dgVDBP (630·106 counts). The calculated ratio of the radical/macrophage activity was 5-fold lower compared to that of dgVDBP. Only VitD-dgVDBP activated caspase-3 (8%), caspase-9 (13%), and cytochrome-C (11%) on prostatic cancer cells. PE-Cy7-labeled VitD-dgVDBP was found to bind to cytotoxic suppressor cells, monocytes/macrophages, dendritic and natural killer cells (CD8+), and helper cells (CD4+). After 12 h of co-incubation of nPBMCs with VitD-dgVDBP, significant activation and expression were measured for CD16++/CD16 (0.6 ± 0.1% vs. 0.4 ± 0.1%, p < 0.05), CD45k+ (96.0 ± 6.0% vs. 84.7 ± 9.5%, p < 0.05), CD85k+ (24.3 ± 13.2% vs. 3.8 ± 3.2%, p < 0.05), and CD85k+/CD123+ (46.8 ± 8.1% vs. 3.5 ± 3.7%, p < 0.001) compared to the control experiment. No significant difference was found using CD3+, CD4+, CD8+, CD4/CD8, CD4/CD8, CD16+, CD16++, CD14+, or CD123+. A significant decline in CD14+/CD16+ was obtained in the presence of VitD-dgVDBP (0.7 ± 0.2% vs. 3.1 ± 1.7%; p < 0.01). Conclusion: The newly developed water-soluble VitD3 form VitD-dgVDBP affected cytotoxic suppressor cells by activating the low radical-dependent CD16 pathway and seemed to induce apoptosis in malignant prostatic cells.

Alpha-Ketoglutarate and 5-HMF: A Potential Anti-Tumoral Combination against Leukemia Cells.

We have recently shown that a combined solution containing alpha-ketoglutarate (aKG) and 5-hydroxymethyl-furfural (5-HMF) might have anti-tumoral potential due to its antioxidative activities. The question arises if these substances have caspase-3- and apoptosis-activating effects on the cell proliferation in Jurkat and HF-SAR cells. Antioxidative capacity of several combined aKG + 5-HMF solution was estimated by cigarette smoke radical oxidized proteins of fetal calf serum (FCS) using the estimation of carbonylated proteins. The usage of 500 µg/mL aKG + 166.7 µg/mL 5-HMF showed the best antioxidative capacity to inhibit protein modification of more than 50% compared to control measurement. A Jurkat cell line and human fibroblasts (HF-SAR) were cultivated in the absence or presence of combined AKG + 5-HMF solutions between 0 µg/mL aKG + 0 µg/mL 5-HMF and different concentrations of 500 µg/mL aKG + 166.7 µg/mL 5-HMF. Aliquots of Jurkat cells were tested for cell proliferation, mitochondrial activity, caspase activity, apoptotic cells and of the carbonylated protein content as marker of oxidized proteins in cell lysates after 24, 48, and 72 h of incubation. The combined solutions of aKG + 5-HMF were shown to cause a reduction in Jurkat cell growth that was dependent on the dose and incubation time, with the greatest reductions using 500 µg/mL aKG + 166.7 µg/mL 5-HMF after 24 h of incubation compared to 24 h with the control (22,832 cells vs. 32,537 cells), as well as after 48 h (21,243 vs. 52,123 cells) and after 72 h (23,224 cells). Cell growth was totally inhibited by the 500 µg/mL AKG + 166.7 µg/mL solution between 0 and 72 h of incubation compared to 0 h of incubation for the control. The mitochondrial activity measurements supported the data on cell growth in Jurkat cells: The highest concentration of 500 µg/mL aKG + 166.7 µg/mL 5-HMF was able to reduce the mitochondrial activity over 24 h (58.9%), 48 h (28.7%), and 72 h (9.9%) of incubation with Jurkat cells compared not only to the control incubation, but also to the concentrations of 500 µg/mL aKG + 166.7 µg/mL 5-HMF or 375 µg/mL aKG 125 µg/mL 5-HMF, which were able to significantly reduce the mitochondrial activity after 48 h (28.7% or 35.1%) and 72 h (9.9% or 18.2%) compared to 24 h with the control (100%). A slight increase in cell proliferation was found in HF-SAR using the highest concentration (500 µg/mL aKG + 166.7 µg/mL 5-HMF) between 0 h and 72 h incubation of 140%, while no significant differences were found in the mitochondrial activity of HF-SAR in the absence or presence of several combined aKG + 5-HMF solutions. The solutions with 500 µg/mL aKG + 166.7 µg/mL 5-HMF or 250 µg/mL aKG + 83.3 µg/mL 5-HMF showed a significantly higher caspase activity (51.6% or 13.5%) compared to the control (2.9%) in addition to a higher apoptosis rate (63.2% or 31.4% vs. control: 14.9%). Cell lysate carbonylated proteins were significantly higher in Jurkat cells compared to HF-SAR cells (11.10 vs. 2.2 nmol/mg). About 72 h incubation of Jurkat cells with 500 µg/mL aKG + 166.7 µg/mL 5-HMF or 250 µg/mL aKG + 83.3 µg/mL 5-HMF reduced significantly the carbonylated protein content down to 5.55 or 7.44 nmol/mg whereas only the 500 µg/mL aKG + 166.7 µg/mL 5-HMF solution showed a significant reduction of carbonylated proteins of HF-SAR (1.73 nmol/mg).

Alpha-Ketoglutarate: A Potential Inner Mitochondrial and Cytosolic Protector against Peroxynitrite and Peroxynitrite-Induced Nitration?

The generation of peroxynitrite (ONOO-) is associated with several diseases, including atherosclerosis, hypertension, neurodegeneration, cancer, inflammation, and sepsis. Alpha-ketoglutarate (αKG) is a known potential highly antioxidative agent for radical oxidative species such as peroxides. The question arises as to whether αKG is also a potential scavenger of ONOO- and a potential protector against ONOO--mediated nitration of proteins. NMR studies of 1 mM αKG in 100 mM phosphate-buffered saline at pH 7.4 and pH 6.0 were carried out in the presence or absence of a final concentration of 2 mM ONOO-. An ONOO--luminol-induced chemiluminescence reaction was used to measure the scavenging function of several concentrations of αKG; quantification of αKG was performed via spectrophotometric enzymatic assay of αKG in the absence or presence of 0, 1, or 2 mM ONOO-. The nitration of tyrosine residues on proteins was measured on ONOO--treated bovine serum albumin (BSA) in the presence or absence of 0-24 mM αKG by an ELISA technique using a specific anti-IgG against nitro-tyrosine. The addition of ONOO- to αKG led to the formation of succinic acid and nitrite at pH 7.0, but not at pH 6.0, as αKG was stable against ONOO-. The absorbance of enzymatically estimated αKG at the time point of 30 min was significantly lower in favour of ONOO- (1 mM: 0.21 ± 0.03, 2 mM: 0.12 ± 0.05 vs. 0 mM: 0.32 ± 0.02; p < 0.001). The luminol technique showed an inverse logarithmic correlation of the ONOO- and αKG concentrations (y = -2 × 105 ln(x) + 1 × 106; r2 = 0.99). The usage of 4 mM αKG showed a significant reduction by nearly half in the chemiluminescence signal (284,456 ± 29,293 cps, p < 0.001) compared to the control (474,401 ± 18,259); for 20 and 200 mM αKG, there were further reductions to 163,546 ± 26,196 cps (p < 0.001) and 12,658 ± 1928 cps (p < 0.001). Nitrated tyrosine residues were estimated using the ELISA technique. A negative linear correlation was obtained by estimating nitrated tyrosine residues in the presence of αKG (r2 = 0.94): a reduction by half of nitrated tyrosine was estimated using 12 mM αKG compared to the control (326.1 ± 39.6 nmol vs. 844.5 ± 128.4 nmol; p < 0.001).

Effective Increase of Serum Vitamin D3 by IV Application of a Cholecalciferol-N-Acetyl-Galactosamine-Stabilized Dimer: a Clinical Murine Trial Study.

BACKGROUND: Pre-clinical toxicology studies of human Gc-protein (vitamin D binding protein) are of special interest as to the transport of vitamin D and its biological activities. We have demonstrated that the oral application of a special dimeric vitamin D complex reduces oxidative stress and increases the quality of life in autistic children. Therefore, safety and toxic effects of two dimeric cholecalciferol-N-acetyl-galactosamine-albumin complexes were evaluated in increasing intravenous (iv.) vitamin D levels administered in a pre-clinical trial in mice over a 5-week period. METHODS: Over a period of 5 weeks, two times a week, mice received iv. administration of one of the following: (a) 1.2 IE of vitamin D-N-acetyl-galactosamine-albumin (Vitamin D3 NAGA, ImmunoD® group), (b) 1.2 IE of vitamin-D-poly-N-acetyl-galactosamine-albumin (Poly-Nac group), or (c) isotonic saline solution (sham group). Before and after the trial, red and white blood cell panels (RBS, WBC and platelets) were determined. Furthermore, vitamin D levels, electrolytes, and C-reactive protein levels were measured directly before sacrificing. RESULTS: No toxic effects were observed during iv. injection with dimeric vitamin D complexes, neither in the sham group, nor in the two treatment groups. Vitamin D levels increased significantly within 5 weeks in the Poly-Nac group (26.6 ± 8.8 ng/mL; p = 0.001) compared to the sham group (3.1 ± 0.9 ng/mL), and the Poly-Nac group to the ImmunoD group (7.0 ± 3.6 ng/mL; p = 0.003). A significant increase of vitamin D was also obtained in favor of the ImmunoD group compared to the sham (p = 0.03). Electrolytes (K, Na, Cl, Mg, Ca) and C-reactive protein showed no significant differences after administration in all three mice groups. Also, no significant differences were observed between these three groups in the WBC and RBC blood panels. CONCLUSIONS: The two dimeric vitamin D complexes used in this pre-clinical study showed no side or toxic effects after iv. administration in mice, but a sole increase in vitamin D levels without any change in electrolytes or blood cells. Therefore, we assume this newly developed composition to be safe in oral or iv.-administration and further pre-clinical studies can be conducted to evaluate the value in treatment of various diseases related to vitamin D deficiencies.

Lowered Levels of Carbonyl Proteins after Vitamin B Supplementation in Patients with Mild Cognitive Impairment and Alzheimer's Disease.

BACKGROUND: The critical role of neuro-inflammation and oxidative stress in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD) has become evident. OBJECTIVE: The aim of this study is to assess the influence of vitamin supplementation on parameters of oxidative stress, inflammation as well as on cognition in patients with AD and mild cognitive impairment. METHODS: In our study, patients with cognitive impairment and healthy controls were enrolled. All patients were intended to receive vitamin supplementation (vitamin B1, B6, B12 and folic acid) for 3 months. Mini Mental State Examination (MMSE) and laboratory markers [carbonyl proteins (CPs), malondialdehyde, tryptophan (Trp), kynurenine (Kyn), neopterin, folic acid, vitamin B12 level] were assessed for patients and controls at baseline and after 3 months. After half of the patients had been treated for 3 months, analyses were performed resulting in 3 subgroups: healthy controls without supplementation (15 subjects, 11 females), patients with vitamin supplementation (17 subjects, 10 females) and patients without vitamin supplementation (16 subjects, 9 females; baseline values prior to supplementation). RESULTS: Age was significantly higher for the supplemented group (76.4 ± 6.7 years) compared to vitamin-naïve patients (63.3 ± 13.7 years; p < 0.01). The MMSE score was higher in the supplemented group (23.1 ± 4.8 vs. 20.3 ± 9.5) but did not reach significance. Levels of CPs were significantly higher in the vitamin-naïve patients (p < 0.05). Levels of Kyn and the Kyn/Trp ratio were significantly lower in vitamin-naïve patients compared to the supplemented group (p < 0.05). No significant difference was seen for the other markers. CONCLUSION: Vitamin supplementation leads to reduced levels of CPs in patients. Pearson's correlation coefficient shows a negative relation (r = -0.69) between CPs and MMSE. Future trials should assess whether CPs might be suitable markers for monitoring of demented patients.

Determination of Angiotensin-(1-7) with HPLC/Fluorescence-Detection.

Angiotensin-(1-7) is an important active component in the renin-angiotensin-system. Due to its cardio protective effects it is now under investigation in combination with antioxidants as a reperfusion solution. The combination showed impressive effects on isolated hearts of male Wistar rats after induced ischemia. In this work a high performance liquid chromatography method with fluorescence detection was developed for the first time for in-process measurements as well as for stability tests of the peptide in the novel antioxidant-containing Karal® solution. For fluorescence detection of angiotensin-(1-7) fluorescamine as derivatization dye was applied. Under optimized conditions the method showed linearity over the range of 50 to 5000 ng/mL with R(2) of 0.9988 and an overall precision better than 5.0 %. LOD and LOQ were determined to be in the femtomol range on column. It was found that stability of angiotensin-(1-7) could be significantly improved in the antioxidant containing preparation compared to aqueous solutions.

Effects of zeolite supplementation on parameters of intestinal barrier integrity, inflammation, redoxbiology and performance in aerobically trained subjects.

BACKGROUND: Zeolites are crystalline compounds with microporous structures of Si-tetrahedrons. In the gut, these silicates could act as adsorbents, ion-exchangers, catalysts, detergents or anti-diarrheic agents. This study evaluated whether zeolite supplementation affects biomarkers of intestinal wall permeability and parameters of oxidation and inflammation in aerobically trained individuals, and whether it could improve their performance. METHODS: In a randomized, double-blinded, placebo controlled trial, 52 endurance trained men and women, similar in body fat, non-smokers, 20-50 years, received 1.85 g of zeolite per day for 12 weeks. Stool samples for determination of intestinal wall integrity biomarkers were collected. From blood, markers of redox biology, inflammation, and DNA damage were determined at the beginning and the end of the study. In addition, VO2max and maximum performance were evaluated at baseline and after 12 weeks of treatment. For statistical analyses a 2-factor ANOVA was used. RESULTS: At baseline both groups showed slightly increased stool zonulin concentrations above normal. After 12 weeks with zeolite zonulin was significantly (p < 0.05) decreased in the supplemented group. IL-10 increased tendentially (p < 0.1) in the zeolite group. There were no significant changes observed in the other measured parameters. CONCLUSIONS: Twelve weeks of zeolite supplementation exerted beneficial effects on intestinal wall integrity as indicated via decreased concentrations of the tight junction modulator zonulin. This was accompanied by mild anti-inflammatory effects in this cohort of aerobically trained subjects. Further research is needed to explore mechanistic explanations for the observations in this study.

Application of Hyperbaric Oxygen Reduce Oxidative Damage of Plasmatic Carbonyl Proteins and 8-OHdG by Activating Glutathion Peroxidase.

BACKGROUND: It is postulated that application of hyperbaric oxygenation may induce the production of radicals after HBO. Higher oxygenation and transport of oxygen increase the mitochondrial energy turnover, whereas inner mitochondrial radical formation decreases. METHODS: Several markers of oxidative stress in healthy volunteers (n = 21), including plasma carbonyl proteins (CP), malondialdehyde (MDA), oxidized LDL (oxLDL), 8-hydroxy-deoxyguanosine (8-OHdG), and erythrocyte glutathione peroxidase (GPx) activity are measured before, during, and after HBO. RESULTS: Median plasma concentrations of CP decreased significantly during HBO compared to CP levels before HBO (from 77.1 to 61.7 pmol/mg; p < 0.001) and increased again after HBO (to 78.1 pmol/mg; p = 0.035). 8-OHdG decreased significantly during HBO (8.1 ng/mL; p < 0.001) and remained constant after HBO (8.1 ng/mL) compared to "before HBO" (9.4 ng/mL). MDA increased significantly from 0.92 µM (before HBO) to 1.26 µM (during HBO, p < 0.01) and decreased again to 1.00 µM (after HBO, p = 0.023). Erythrocyte GPx activity also increased significantly during HBO (26.5 ± 14.7; p = 0.005), but not after HBO (25.6 ± 17.2 IU/mg). A negative correlation was observed between GPx and MDA only during HBO (r = -0.518; p = 0.016). CONCLUSIONS: We assume that higher oxygen consumption decreases, on the one hand, the inner mitochondrial generation of free radicals and, on the other, RONS by activation of detoxifying enzymes like GPx.

Effects of antioxidant supplementation on exercise performance in acute normobaric hypoxia.

BACKGROUND/OBJECTIVES: To compare the effects of a 3-week supplementation between two different mixtures of antioxidants and placebo on aerobic exercise performance in acute normobaric hypoxia. SUBJECTS/METHODS: Seventeen subjects were randomly assigned in a double-blind fashion to receive a broad-based antioxidants supplement containing beta-carotene, ascorbic acid, d-alpha-tocopherol-succinate, N-acetylcysteine, riboflavin, zinc, and selenium (antioxidant capsule group [AO group]), or a combination of alpha-ketoglutaric acid (α-KG) and 5-hydroxymethylfurfural (5-HMF; CYL concentrate supplementation group [CS group]), or placebo (PL group). Before and after supplementation, subjects performed two incremental cycle-exercise tests until exhaustion. The first test was conducted under normoxic conditions (LA, FiO2 of 20.9%, ~547 m) and the second after the 3-week supplementation period under normobaric hypoxic conditions (AHA, FiO2 of 12.9%, ~4300m). RESULTS: In CS peak cycling performance (peak power) declined from LA to AHA 7.3% (90% CI: 2.2-12.4) less compared with PL (p = .04) and 6.7% (90%CI: 3.2-10.2) less compared with AO (p = .03). Better maintenance of aerobic exercise capacity in CS was associated with an attenuated reduction in maximal heart rate in hypoxia. CONCLUSIONS: Aerobic exercise performance was less impaired in acute normobaric hypoxia after 3 weeks with supplementation of α-KG and 5-HMF compared with a broad-based antioxidants supplement or PL.

Elevated levels of carbonyl proteins in cerebrospinal fluid of patients with neurodegenerative diseases.

The importance of oxidative stress in the pathogenesis of neuroimmunological and neurodegenerative diseases, such as multiple sclerosis (MS), has been discussed for a long time. However, markers for oxidative stress in cerebrospinal fluid are hardly detected. The aim of the present study is to assess whether carbonyl proteins as end products of metabolic processes may serve as a marker for oxidative stress in the cerebrospinal fluid (CSF) of patients with neuroimmunological and neurodegenerative diseases. Levels of carbonyl proteins in the CSF were assessed in 15 patients suffering from MS, four patients with neurodegenerative diseases, including one patient with dementia complicated by carcinomatous meningitis due to breast cancer, and four control subjects with no established neurological disease. Levels of carbonyl proteins were measured with a commercially available KIT. A significant difference (P = 0.025) was shown for mean values of various subgroups with highest levels for patients with neurodegenerative diseases (756.1 pmol/mg), followed by the MS (630.8 pmol/mg) and the control group (356.5 pmol/mg). Post-hoc pair wise comparisons showed significant differences between the MS group and healthy controls (P = 0.016) as well as for patients with neurodegenerative diseases and healthy controls (P = 0.02). This pilot trial showed that carbonyl proteins might serve as measure for oxidative stress in the CSF of relapsing as well as progressive MS patients and in patients with neurodegenerative diseases. Larger trials have to show whether they may serve as biomarkers and be helpful in monitoring patients with MS or neurodegenerative diseases.

Simultaneous quantitation of alpha-ketoglutaric acid and 5-hydroxymethylfurfural in plasma by HPLC with UV and fluorescence detection.

Alpha-ketoglutaric acid (KG) and hydroxymethylfurfural (HMF) are currently being investigated in clinical trials as an approach in targeted cancer therapy. Hence, a method for the simultaneous determination of KG and HMF in plasma has been developed. Due to the strongly discriminative chemical properties of KG and HMF, SPE purification is performed using an ion-exchange cartridge to separate KG, and a hydrophobic polymeric cartridge to separate HMF. The cartridges are connected together for several steps, thus resulting in a quicker approach for the purification of plasma samples. The derivatization step is based on the reaction of the carbonyl groups of KG and HMF with dansylhydrazine (DNSH) catalyzed by trifluoroacetic acid. The formed derivatives could be separated by reversed-phase LC on a C8-column, and analyzed by UV and fluorescence detection in a single run using a gradient program. The obtained results show good reproducibility, specificity, and detection limits down to the low picomole range.

Proteomic analysis of seminal plasma from infertile patients with oligoasthenoteratozoospermia due to oxidative stress and comparison with fertile volunteers.

OBJECTIVE: To compare the expression protein profile of seminal plasma from infertile men with oligoasthenoteratozoospermia (OAT) due to oxidative stress with that of healthy, fertile men to determine the proteins indicative of infertility. DESIGN: Experimental study. SETTING: University hospital and research institute. PATIENT(S): Semen samples from 11 healthy, fertile (according to the 1999 World Health Organization criteria) male volunteers and 11 infertile idiopathic oligoasthenoteratozoospermia (iOAT) patients. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Proteomic analysis performed by liquid chromatography mass spectrometry on a hybrid linear trap quadrupole Orbitrap Velos mass spectrometer, carbonylation assay to determine degree of oxidative stress, semiquantitative proteomic analysis, gene ontology, and pathway analysis. RESULT(S): A total of 2,489 proteins were identified from seminal plasma, which represents the highest number of unique proteins identified to date. Twenty-four proteins were determined as ≥ 1.5-fold up-regulated in the infertile iOAT males as compared with the fertile controls; and 27 proteins from iOAT patients only were identified as common across all analyses. Only five of the proteins were shared between these two groups. CONCLUSION(S): A panel of 46 proteins were identified in patients with iOAT that are potential candidates in understanding the etiology of OAT due to oxidative stress.

Supplementation with a juice powder concentrate and exercise decrease oxidation and inflammation, and improve the microcirculation in obese women: randomised controlled trial data.

Obesity and sedentary lifestyle are associated with increased oxidative stress, inflammation and vessel dysfunction. Previous research has shown that an encapsulated fruit/berry/vegetable juice powder (FBV) supplement or controlled exercise training improve the markers of redox biology, low-grade inflammation and circulation. The aim of the present study was to assess the effects of 8 weeks of supplementation with FBV or placebo, and a single bout of controlled walking on the markers of oxidation, inflammation and skin capillary microcirculation in forty-two obese pre-menopausal women (41 (SD 5) years, non-smokers and BMI 34·5 (SD 3·8) kg/m(2)) using a randomised, double-blind, placebo-controlled design. All assessments were made before and after 8 weeks of capsule supplementation, and pre- and post-30 min of controlled treadmill walking at 70 % of VO2max. Venous blood was collected for the determination of carbonyl proteins (CP), oxidised LDL (ox-LDL), total oxidation status (TOS) of lipids, malondialdehyde, TNF-α and IL-6. Capillary blood flow, O2 saturation of Hb (SO2Hb) and the relative concentration of Hb (rHb) were assessed at a 2 mm skin depth. Following 8 weeks of supplementation, compared with placebo, the FBV group had a significant (P< 0·05) reduction in CP, ox-LDL, TOS and TNF-α, and a significant increase in blood flow, SO2Hb and rHb. Independent of supplementation, moderate exercise significantly increased blood flow and rHb, with a trend towards increased SO2Hb. Compared with placebo, 8 weeks of supplementation with FBV decreased the markers of systemic oxidation and inflammation. Both FBV supplementation and a single walking bout improved the markers of the microcirculation in these obese women.

Determination of metabolites of 5-hydroxymethylfurfural in human urine after oral application.

5-Hydroxymethylfurfural (5-HMF) is a natural occurring substance taken up by everyday food. In former studies it was shown that 5-HMF is completely decomposed in the body after oral or intravenous application resulting in three main metabolites named 5-hydroxymethylfuroic acid, 2,5-furandicarboxylic acid, and N-(hydroxymethyl)furoyl glycine, and possibly a forth metabolic substance, termed 5-sulphoxymethylfurfural, is formed. Determination is possible via HPLC using a hydrophilic interaction chromatography (HILIC) column with an appropriate gradient system (ACN/ammonium formate 100 mM, pH 2.35). Urine samples were purified by use of an SPE method beforehand working with ScreenA cartridges. This cleaning procedure was validated based on ICH guidelines in terms of linearity, quantification, and detection limit, as well as precision, repeatability, and accuracy. Analysis of real-life samples coming from two healthy probands and one cancer patient, who all received 240 mg 5-hydroxymethylfurfural orally once a day, showed dicarboxylic acid and the glycine conjugate in their urine samples. Recovery of the initial compound in form of transformed metabolites was up to 90% within 48 h. Potentially toxic 5-sulphoxymethylfurfural could not be found.

Probiotic supplementation affects markers of intestinal barrier, oxidation, and inflammation in trained men; a randomized, double-blinded, placebo-controlled trial.

BACKGROUND: Probiotics are an upcoming group of nutraceuticals claiming positive effects on athlete's gut health, redox biology and immunity but there is lack of evidence to support these statements. METHODS: We conducted a randomized, double-blinded, placebo controlled trial to observe effects of probiotic supplementation on markers of intestinal barrier, oxidation and inflammation, at rest and after intense exercise. 23 trained men received multi-species probiotics (1010 CFU/day, Ecologic®Performance or OMNi-BiOTiC®POWER, n = 11) or placebo (n = 12) for 14 weeks and performed an intense cycle ergometry over 90 minutes at baseline and after 14 weeks. Zonulin and α1-antitrypsin were measured from feces to estimate gut leakage at baseline and at the end of treatment. Venous blood was collected at baseline and after 14 weeks, before and immediately post exercise, to determine carbonyl proteins (CP), malondialdehyde (MDA), total oxidation status of lipids (TOS), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Statistical analysis used multifactorial analysis of variance (ANOVA). Level of significance was set at p < 0.05, a trend at p < 0.1. RESULTS: Zonulin decreased with supplementation from values slightly above normal into normal ranges (<30 ng/ml) and was significantly lower after 14 weeks with probiotics compared to placebo (p = 0.019). We observed no influence on α1-antitrypsin (p > 0.1). CP increased significantly from pre to post exercise in both groups at baseline and in the placebo group after 14 weeks of treatment (p = 0.006). After 14 weeks, CP concentrations were tendentially lower with probiotics (p = 0.061). TOS was slightly increased above normal in both groups, at baseline and after 14 weeks of treatment. There was no effect of supplementation or exercise on TOS. At baseline, both groups showed considerably higher TNF-α concentrations than normal. After 14 weeks TNF-α was tendentially lower in the supplemented group (p = 0.054). IL-6 increased significantly from pre to post exercise in both groups (p = 0.001), but supplementation had no effect. MDA was not influenced, neither by supplementation nor by exercise. CONCLUSIONS: The probiotic treatment decreased Zonulin in feces, a marker indicating enhanced gut permeability. Moreover, probiotic supplementation beneficially affected TNF-α and exercise induced protein oxidation. These results demonstrate promising benefits for probiotic use in trained men. CLINICAL TRIAL REGISTRY: http://www.clinicaltrials.gov, identifier: NCT01474629.

Method development and validation for the analysis of a new anti-cancer infusion solution via HPLC.

A fast and simple HPLC method has been developed and validated for the quantification of a completely new anti-cancer drug during the manufacturing process. The combination of four compounds including α-ketoglutaric acid, hydroxymethylfurfural, N-acetyl-L-methionine and N-acetyl-L-selenomethionine, administered intravenously, is still in test phase but has already shown promising results in cancer therapy. HPLC separation was achieved on an RP-18 column with a gradient system. However, the highly different concentrations of the compounds required a variation in the detection wavelength within one run. In order to produce a chromatogram where peaks were comparable on a similar range scale, detection at absorption maxima for the two most concentrated components was avoided. After optimization of the gradient program it was possible to detect all four substances within 14 min in spite of their strongly different chemical structure. The method developed was validated for accuracy, repeatability, reproducibility and robustness in relation to temperature and pH of buffer. Linearity as well as the limit of detection and quantification were determined. This HPLC method was found to be precise, accurate and reproducible and can be easily used for in-line process control during the manufacture of the anti-tumour infusion solution.

Carbonyl proteins as a clinical marker in Alzheimer's disease and its relation to tryptophan degradation and immune activation.

BACKGROUND: The question arises whether oxidative stress is connected with systemic immune activation in Alzheimer's disease (AD) and mild cognitive impairment (MCI). During immune response interferon-gamma stimulates the kynurenine (Kyn) pathway, a major route of L-tryptophan (Trp) degradation. METHODS: Plasma Kyn, Trp and the Kyn to Trp ratio (Kyn/Trp), carbonyl proteins (CP) as oxidative stress parameter and homocysteine, neopterin, folate and vitamin B12 were measured from patients with AD and MCI (n = 16: 6 females and 4 males with AD, 3 females and 3 males with MCI; 63.3 +/- 13.7 years), and an age matched healthy control group (n = 15: 11 females and 4 males; 62.8 +/- 3.6 years). We correlated the oxidative stress parameter CP with the degradation of Trp creating a new quotient CP/Trp and calculated the sensitivity, specificity, and cut-off values for CP, Trp, CP/Trp, and Kyn/Trp using discriminate analysis. RESULTS: CP was significantly higher in AD/MCI (930 +/- 265 pmol/mg; p < 0.001) compared to controls (300 +/- 120 pmol/mg), Trp was significantly lower in AD/MCI (48.9 +/- 9.0 micromol/L; p < 0.001) than controls (65.2 +/- 10.7 micromol/L). While Kyn showed no significant difference between AD/MCI (1.72 +/- 0.56 micromol/L) and controls (1.53 +/- 0.29 micromol/L), Kyn/Trp was significantly higher in AD/MCI (35.2 +/- 8.8 micromol/mmol; p < 0.001) than in controls (23.7 +/- 4.2 micromol/mmol). CP/Trp ratio was more than 4 fold higher in the AD/MCI group (19.8 +/- 7.76 [(pmol/mg)/(micromol/L)]; p < 0.001) compared to controls (4.79 +/- 2.26 [(pmol/mg)/(micromol/L)]). Homocysteine, folate, vitamin B12, and neopterin showed no significant difference. Discriminant analysis provided CP alone as the best clinical marker with highest sensitivity and highest specificity for AD/MCI followed by the ratio of CP/Trp. ROC curve analysis provided the best result for CP/Trp. CONCLUSIONS: These preliminary results support the hypothesis that oxidative damage to proteins is directly connected with Trp degradation and Kyn pathway in the systemic immune activation.