Introduction: 5-HMF is a molecule found in carbohydrate-rich foods that is associated not only with cancer and anaphylactic reactions, but also with anti-oxidant properties. Questions arose as to whether 5-HMF exhibited a catalytic effect in relation to lipid peroxidation and lipoprotein oxidation in presence of metals and/or radicals. Methods: Peroxynitrite (ONOO−)-induced chemiluminescence and ONOO− nitration of tyrosine residues on BSA using anti-nitro-tyrosine-antibodies were used to measure the protection of 5-HMF against peroxides or nitration compared to vitamin C (VitC). The reductive potential of 5-HMF or VitC on Cu2+ or Fe3 was estimated using the bicinchoninic acid (BCA) or Fenton-complex method. Human plasma was used to measure the generation of malondialdehyde (MDA), 4-hydroxynonenal (HNE), and total thiols after Fe2+/H2O2 oxidation in the presence of different concentrations of 5-HMF or VitC. Finally, Cu2+ oxidation of LDL after 4 h was carried out with 5-HMF or VitC, measuring the concentration of MDA in LDL with the thiobarbituric assay (TBARS). Results: VitC was 4-fold more effective than 5-HMF in scavenging ONOO− to nearly 91.5% at 4 mM, with the exception of 0.16 mM, where the reduction of ONOO− by VitC was 3.3-fold weaker compared to 0.16 mM 5-HMF. VitC or 5-HMF at a concentration of 6 mM inhibited the nitration of tyrosine residues on BSA to nearly 90% with a similar course. While 5-HMF reduced free Fe3+ in presence of phenanthroline, forming Fe2+ (phenantroleine)3 [Fe2+(phe)3] or complexed Cu2+(BCA)4 to Cu+(BCA)4 weakly, VitC was 7- to 19-fold effective in doing so over all the used concentrations (0–25 mM). A Fe2+—H2O2 solution mixed with human plasma showed a 6–10 times higher optical density (OD) of MDA or HNE in the presence of 5-HMF compared to VitC. The level of thiols was significantly decreased in the presence of higher VitC levels (1 mM: 198.4 ± 7.7 µM; 2 mM: 160.0 ± 13.4 µM) compared to equal 5-HMF amounts (2562 ± 7.8 µM or 242.4 ± 2.5 µM), whereas the usage of lower levels at 0.25 µM 5-HMF resulted in a significant decrease in thiols (272.4 ± 4.0 µM) compared to VitC (312.3 ± 19.7 µM). Both VitC and 5-HMF accelerated copper-mediated oxidation of LDL equally: while the TBARS levels from 4 h oxidized LDL reached 137.7 ± 12.3 nmol/mg, it was 1.7-fold higher using 6 mM VitC (259.9 ± 10.4 nmol/mg) or 6 mM 5-HMF (239.3 ± 10.2 nmol/mg). Conclusions: 5-HMF appeared to have more pro-oxidative potential compared to VitC by causing lipid peroxidation as well as protein oxidation.

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.

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).

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).

Aim: Coronavirus Disease (COVID-19) is caused by the newly emerged coronavirus SARS-CoV-2.To prevent further spread of SARS-CoV-2 and to provide a possible prophylaxis and treatment option we report about our experience on the application of two preparations with a clinical complete recovery of five patients, including two breastfed babies, from a Coronavirus disease with severe symptoms.Material and methods: Sedeprovid (ImmunoD ® CLS ℗ ) were applied twice a day and AlphaH ℗ 20 ml concentrate was consumed once a day in the morning.The course of disease and symptoms before, during and after treatment were recorded.Results: Prior to treatment, the patients suffered from severe symptoms of confirmed COVID-19 infections, including cough, inappetence, tiredness, bone and body pain, loss of taste and smell and body temperature of ≥39ºC for several days.Within 24 hours after application of ImmunoD ® CLS ℗ and AlphaH ℗ a significant reduction of symptoms and a drop down of maximal body temperature was recorded.A complete recovery with normal body temperature and normal or close to normal activity was documented after 48 hours.No side effects were reported from the patients or the parents. Conclusion:The combination of ImmunoD ® CLS ℗ and AlphaH ℗ might offer a good treatment regimen for COVID-19 infected patients with moderate and severe disease progression before entering or after leaving the ICU ward.In addition, this protocol might be used as a prophylactic therapy option for healthcare providers.We strongly recommend the instant confirmation of these results in a controlled randomized trial for a possible rapid benefit of COVID-19 infected patients.We recently reported a newly developed dimeric compound, namely cholecalciferol-N-acetylgalactosamine-Vitamin D binding protein (VitD~dgVDBP) and its positive and non-toxic effects after intravenous injection compared to sham group in mice [9].In addition, VitD~dgVDBP (Il-42 / Sedeprovid) showed a higher macrophage activation and a lower oxidative burst than Vitamin D free dgVDBP and VDBP.That may result from a synergistic effect through a better presentation / exposition of protein bound Vitamin D to macrophages [10].This special Vitamin D form has shown to have no side effects yet, even in high doses, neither as oral nor as iv.-application form, both in animals [9] and humans [11,12].Herwig R (2020) Sedeprovid, a novel vitamin D based substance, plus AlphaH ℗ lead to complete recovery from COVID-19 within 48 hours after application in a 7-months old baby, a 1.5-year-old toddler and three further adults

BACKGROUNDPre-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.METHODSOver 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.RESULTSNo 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.CONCLUSIONSThe 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.

Exposure to cigarette smoke increase the formation of oxidatively modified proteins, lipids, DNA/RNA and carbohydrates in humans.These toxic substances are involved in several pathologies such as, e.g., cancer.Antioxidative supplementation is known to decrease the formation of oxidatively modified proteins, namely, carbonyl proteins.A newly developed combination of 2-oxoglutarate/ascorbic acid/5-hydroxy-methyl-furfur-aldehyde/carnosine was estimated as to the protection of generated carbonyl proteins in vivo and in vitro.Methods: Carbonyl protein content in human plasma of 15 smokers and 15 non-smokers were estimated with the Carbonylprotein ELISA, and in erythrocyte proteins with the spectro-photometically method.15 smokers were randomly assigned to drink the combination of 2-oxoglutarate/ascorbic acid/5-hydroxy-methylfurfur-aldehyde over 4 weeks.Plasma carbonyl proteins were measured before and after 2 and 4 weeks of supplementation.In vitro studies of cigarette smoke modified proteins in absence or presence of the combination of 2-oxoglutarate/ascorbic acid/5-hydroxy-methyl-furfur-aldehyde/ carnosine or the separate substances 2-oxoglutarate, ascorbic acid, and 5-hydroxy-methyl-furfur-aldehyde were measured with the carbonyl protein spectrophotometically method before, after 2, 15 and 30 minutes.Results: Carbonyl protein in plasma was significantly higher in smokers (448±223 pmol/mg) as compared to non-smokers (191±40 pmol/mg; p<0.02), highly significant in erythrocyte proteins (26.8±12.9nmol/mg vs. 12.1±0.3nmol/mg; p<0.001).After 4 weeks the supplemented group showed significant lower carbonyl proteins (228±11 pmol/mg) as compared to the non-supplemented (325±45 pmol/mg; p<0.001).In vitro, smoking of BSA solution showed a significant reduction of generated carbonyl proteins in the presence of the combined supplements after 2 min.(2.18±0.34nmol/mg vs. 5.94 nmol/mg±0.43nmol/mg; p<0.001), 15 (2.81±0.31nmol/mg vs. 7.96±0.79nmol/mg; p<0.001), 30 min.(3.39±0.32nmol/mg vs. 9.89 nmol/ mg±0.07 nmol/mg; p<0.001) and 60 min.(3.85±0.63nmol/mg vs. 11.51nmol/mg±0.94nmol/mg; p<0.001) compared to BSA solution without supplements.Using seperate substances at concentrations of 0.106 mM 2-oxo-glutarate showed a significant reduction of carbonyl proteins after 2 min.(48.5%), 15 min.(52.3%), 30 min.(54.6%) and 60 min.(54.7%) incubation with cigarette smoke, vitamin C: 2 min.(41,4%), 15 min.(41.8%), 30 min.(42.7%) and 60 min.(45.0%).5-HMF: 2 (13.8%), 15 (12.3%), 30 (7.8%) and 60 min.(10.9%). Conclusion:In vivo study in smokers and in vitro studies showed a significant reduction of oxidatively modified proteins in the presence of a combined supplement mixture containing 2-oxoglutarate/ascorbic acid/5-hydroxy-methyl-furfur-aldehyde/carnosine.This generally leads to various degenerative pulmonary and cardiovascular diseases like bronchitis, emphysema, myocardial

Background: Question arises if Amyotrophic lateral sclerosis (ALS, Lou-Gehrig-Syndrom, Charcot-disease) is considered to be an autoimmune disorder that affects the nerval filaments of α-motoneurons in the central nervous system (CNS) due to oxidative stress.SOD mutations seem to play a genetic disorder role in glycosylation and oxidative modifications of neuronal filaments.Vitamin D (VitD) and Vitamin D binding protein (VDBP) has potency to act as an immune modulator.The present study was undertaken to examine the effects of a 34-week vitD supplementation of ImmunoD  , a stabilized Vitamin D3 complex, in a patient with ALS on oxidative stress parameters, nitrosative stress parameter, VitD status and VDBP.Results: This case study showed early beneficial responses, especially improvement of motor dysfunction after VitD treatment.During treatment lipid peroxidation products like malondialdehyde (MDA), 4-hydroxynonenal (HNE) and hydroxyalkenale (HAE) increased in the first 4 weeks (MDA: 1.00 µM to 4.36 µM; HNE: 1.18 µM to 4.78 µM; HAE: 2.18µM to 9.14 µM), but decreased after 8 and 34 weeks (MDA: 0.89 µM to 0.76 µM; HNE: 0.75 µM to 0.68 µM; HAE: 1.64 µM to 1.44 µM).Carbonyl proteins showed the same trend (0 weeks: 245 pmol/mg, 4 weeks: 392 pmol/mg, 8 weeks: 284 pmol/mg and 34 weeks: 211 pmol/mg but not total oxidative status and nitrated tyrosine proteins.VitD and VDBP increased after 34 weeks therapy compared before treatment (VitD before treatment: 150.4 ng/ mL, after 34 weeks: 194.8 ng/mL; VDBP before treatment: 175.7 mg/mL, after 34 weeks: 225 mg/mL): Oxidative stress, VitD and VDBP seem to be involved in the pathogenesis of ALS.

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.

Oxidative and nitrosative stress is expressed in significantly increased generation of reactive oxygen and nitrogen species (RONS) against a sophisticated regulated enzymatic and non-enzymatic antioxidant system, depending on the stress intensity, exposure time and frequency. The determination of Carbonyl Proteins is a widely used oxidative stress marker generated from different sources such as free radicals, trace amounts of metals, lipid peroxidation from polyunsaturated fatty acids, carbohydrate degradation and direct oxidation of free radicals or RONS. The extent of occurrence of oxidative and nitrosative stress depends strongly on the model of exercise. Reactive intermediates produced under conditions of oxidative stress cause the oxidation of polyunsaturated fatty acids in membrane lipid bilayers, leading to the formation of aldehydes. In contrast to the short-living free radicals, the breakdown products of lipid peroxides may serve as 'oxidative stress second messengers', due to their prolonged half-life and their ability to diffuse from their site of formation.

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.

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 mu mol/L; p < 0.001) than controls (65.2 +/- 10.7 mu mol/L). While Kyn showed no significant difference between AD/MCI (1.72 +/- 0.56 mu mol/L) and controls (1.53 +/- 0.29 mu mol/L), Kyn/Trp was significantly higher in AD/MCI (35.2 +/- 8.8 mu mol/mmol; p < 0.001) than in controls (23.7 +/- 4.2 mu mol/mmol). CP/Trp ratio was more than 4 fold higher in the AD/MCI group (19.8 +/- 7.76 [(pmol/mg)/(mu mol/L)]; p < 0.001) compared to controls (4.79 +/- 2.26 [(pmol/mg)/(mu mol/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. (Clin. Lab. 2010;56:441-448)

The question arises as to whether oxidative stress has a primary role in neurodegeneration or is a secondary end-stage epiphenomenon. The aim of the present study was to determine oxidative stress parameters like malondialdehyde (MDA), carbonyl proteins (CP) and Albumin-disulphide (Alb-SSR) and relate these parameters to the immune parameter neopterin, folic acid and vitamin B12 as vitamins and homocysteine in patients with neuro-degenerative diseases (NDD), namely mild cognitive impairment (MCI) and Alzheimer's disease (AD) compared to an aged matched control group. MDA, CP and Alb-SSR were significantly increased in the NDD group compared to controls, but not vitamin B12, folic acid and neopterin. Significant correlations were found between CP and Alb-SSR, CP and MDA and between MDA and Alb-SSR including patients with NDD and the control group. These results support the hypothesis that oxidative damage to lipids and proteins is an important early event in the pathogenesis of neurodegenerative diseases.