General Rehabilitation Program after Knee or Hip Replacement Significantly Influences Erythrocytes Oxidative Stress Markers and Serum ST2 Levels.

The survival of erythrocytes in the circulating blood depends on their membranes' structural and functional integrity. One of the mechanisms that may underlie the process of joint degeneration is the imbalance of prooxidants and antioxidants, promoting cellular oxidative stress. The study is aimed at observing the effects of the 21-day general rehabilitation program on the erythrocytes redox status and serum ST2 marker in patients after knee or hip replacement in the course of osteoarthritis. Erythrocytes and serum samples were collected from 36 patients. We analyzed the selected markers of the antioxidant system in the erythrocytes: catalase (CAT), glutathione reductase (glutathione disulfide reductase (GR, GSR)), total superoxide dismutase activity (SOD), glutathione peroxidase (GPx), glutathione transferase (GST) activity, and cholesterol and lipofuscin (LPS) concentration. In serum, we analyzed the concentration of the suppression of tumorigenicity 2 (ST2) marker. After the 21-day general rehabilitation program, the total SOD and GPx activity, measured in the hemolysates, significantly increased (p < 0.001) while LPS, cholesterol, and ST2 levels in serum significantly decreased (p < 0.001). General rehabilitation reduces oxidative stress in patients after knee or hip replacement in the course of osteoarthritis. Individually designed, regular physical activity is the essential element of the postoperative protocol, which improves the redox balance helping patients recover after the s4urgery effectively.

A Novel Quantitative Method for the Detection of Lipofuscin, the Main By-Product of Cellular Senescence, in Fluids.

Lipofuscin accumulation is a hallmark of senescence. This nondegradable material aggregates in the cytoplasm of stressed or damaged cells due to metabolic imbalance associated with aging and age-related diseases. Indications of a soluble state of lipofuscin have also been provided, rendering the perspective of monitoring such processes via lipofuscin quantification in liquids intriguing. Therefore, the development of an accurate and reliable method is of paramount importance. Currently available assays are characterized by inherent pitfalls which demote their credibility. We herein describe a simple, highly specific and sensitive protocol for measuring lipofuscin levels in any type of liquid. The current method represents an evolution of a previously described assay, developed for in vitro and in vivo senescent cell recognition that exploits a newly synthesized Sudan Black-B analog (GL13). Analysis of human clinical samples with the modified protocol provided strong evidence of its usefulness for the exposure and surveillance of age-related conditions.

The Evaluation of Oxidative Stress Parameters in Serum Patients with Relapsing-Remitting Multiple Sclerosis Treated with II-Line Immunomodulatory Therapy.

OBJECTIVES: The assessment of oxidative stress (OS) in serum relapsing-remitting multiple sclerosis patients treated with II-line immunomodulatory therapy (fingolimod, natalizumab) compared to newly diagnosed patients (de novo group) treated with interferon (IFN) beta and controls. The relationship between OS parameters and gender, age, disease duration, Expanded Disability Status Scale, annualized relapse rate, MRI lesions in patients treated with II-line. MATERIALS AND METHODS: One hundred and twenty-one patients with RRMS were enrolled in the study. Patients were divided into groups: de novo group, IFN, fingolimod (FG), natalizumab (NT), and controls. Lipid hydroperoxides (LHP), malondialdehyde (MDA), lipofuscin (LPS), and total oxidative status (TOS) were determined. RESULTS: LHP, MDA, and TOS were lower in NT and FG groups compared to the de novo group. Levels of OS were different between NT and FG patients and the IFN group. Women treated with FG and NT had lower MDA, LPH, and TOS than women who were not treated while in men only LPH was lowered. Positive correlations were found between MDA, LHP, TOS, and ARR in the NT group. CONCLUSION: The II-line immunomodulatory treatment decreased OS particularly among women. No difference in OS levels was observed between II-line therapy and IFN beta.

Relation of plasma selenium and lipid peroxidation end products in patients with Alzheimer's disease.

Increased oxidative stress in the brain during the course of Alzheimer's disease (AD) leads to an imbalance of antioxidants and formation of free radical reaction end-products which may be detected in blood as fluorescent lipofuscin-like pigments (LFPs). The aim of this study was to evaluate and compare LFPs with plasma selenium concentrations representing an integral part of the antioxidant system. Plasma samples from subjects with AD dementia (ADD; n=11), mild cognitive impairment (MCI; n=17) and controls (n=12), were collected. The concentration of selenium was measured using atomic absorption spectroscopy. LFPs were analyzed by fluorescence spectroscopy and quantified for different fluorescent maxima and then correlated with plasma selenium. Lower levels of selenium were detected in MCI and ADD patients than in controls (P=0.003 and P=0.049, respectively). Additionally, higher fluorescence intensities of LFPs were observed in MCI patients than in controls in four fluorescence maxima and higher fluorescence intensities were also observed in MCI patients than in ADD patients in three fluorescence maxima, respectively. A negative correlation between selenium concentrations and LFPs fluorescence was observed in the three fluorescence maxima. This is the first study focused on correlation of plasma selenium with specific lipofuscin-like products of oxidative stress in plasma of patients with Alzheimer´s disease and mild cognitive impairment.

Differences in serum oxidative status between glaucomatous and nonglaucomatous cataract patients.

BACKGROUND: Oxidative stress contributes to both intraocular pressure regulation and glaucomatous neuropathy. The systemic redox status (solitary determination) was examined in primary open-angle glaucoma (POAG) patients with cataract and nonglaucomatous cataract patients. Cataract-matched group comparisons appear more precise in the context of oxidative stress evaluation. The aim of this study was to establish if systemic oxidative status in POAG patients was elevated compared with the cataract only subjects. METHODS: The study included patients with primary open angle glaucoma (POAG group, n = 30) and controls (non POAG group, n = 25). Serum concentration of lipofuscine (LPS), malondialdehyde (MDA) and activity of total superoxide dismutase (SOD), and its mitochondrial (Mn-SOD) and cystolic (Cu,Zn-SOD) isoform were measured. Total oxidant state (TOS) and total antioxidant capacity (TAC) in blood were also evaluated. RESULTS: Significant increase of LPS (p = 0.0002) and MDA (p = 0.005) concentration was observed in glaucomatous patients as compared with controls. Total SOD activity was significantly lowered in the glaucoma group (p = 0.003); serum level of Mn-SOD was significantly lower in glaucoma patients (p = 0.048) however, Cu,Zn-SOD was not. Glaucoma patients presented elevated mean TOS (p = 0.016). Both groups presented with comparable TAC. CONCLUSION: Systemic redox balance of cataract patients was significantly altered in the course of glaucoma.

Lipofuscin in saliva and plasma and its association with age in healthy adults.

BACKGROUND AND AIM: To compare blood and salivary levels of lipofuscin in healthy adults and to analyze the relationship between the lipofuscin level and the healthy adults' age. METHODS: One hundred and twenty-two healthy volunteers were recruited and divided into three groups according to their age: young (n = 42, 20-44 years old), middle-aged (n = 51, 45-59 years old), and elderly (n = 29, 60-74 years old). One ml saliva and 5 ml whole blood were collected from each person. An ELISA kit was used to measure both the plasma and salivary lipofuscin levels. The differences between the groups were compared with independent-sample t test, and the relationship between the salivary lipofuscin level and the age was assessed with linear regression analysis. RESULTS: The mean ± SD of the lipofuscin level in the saliva and plasma of 122 subjects was 68.93 ± 1.32 and 78.05 ± 1.75 µmol/l, respectively. No gender-dependent differences were observed in either the salivary or the plasma lipofuscin level (saliva: p = 0.443, plasma: p = 0.459). The salivary and plasma lipofuscin levels of the elderly subjects were significantly higher than those of the young (saliva: 80.72 ± 13.53 mmol/l versus 59.12 ± 1.92 mmol/l, p = 0.0003; plasma: 93.31 ± 3.14 mmol/l versus 67.43 ± 2.54 mmol/l, p = 0.0002) and middle-aged (saliva: 80.72 ± 13.53 mmol/l versus 70.31 ± 11.17 mmol/l, p = 0.0004; plasma: 93.31 ± 3.14 mmol/l versus 78.12 ± 2.40 mmol/l, p = 0.0002) subjects. Similarly, the salivary and plasma lipofuscin levels of the middle-aged subjects were significantly higher than those of the young subjects (saliva: 70.31 ± 11.17 mmol/l versus 59.12 ± 1.92 mmol/l, p < 0.0001; plasma: 78.12 ± 2.40 mmol/l versus 67.43 ± 2.54 mmol/l, p = 0.0019). The lipofuscin levels in the saliva and plasma were significantly positively correlated with the subject age (r = 0.551, p = 0.0001; r = 0.528, p < 0.0001). Furthermore, the salivary lipofuscin level and plasma lipofuscin level also were found to have a positive correlation (r = 0.621, p < 0.0001). CONCLUSION: No gender-dependent differences were observed in either the salivary or plasma lipofuscin levels. The salivary and plasma lipofuscin levels were positively correlated, and the age is positively correlated with lipofuscin content in saliva.

Plasma protein lipofuscin-like fluorophores in men with coronary artery disease treated with statins.

BACKGROUND: Lipid oxidation products react with protein to produce lipofuscin-like fluorophores (P-LLF) and modified apolipoprotein B that is an important element of the atherogenic properties of oxidized low-density lipoprotein (oxLDL). The aim of this study was to compare plasma concentrations of P-LLF between men with coronary artery disease (CAD) treated with statin drugs and healthy controls and to identify determinants of P-LLF. METHODS: Plasma markers of protein modification including P-LLF and oxidized low-density lipoprotein-4E6 (oxLDL-4E6), low-density lipoprotein-conjugated dienes (LDL-CD), lipid peroxides, apolipoprotein B, and serum albumin were measured in 24 men with CAD who were receiving statin therapy and 20 healthy men in the same age range. RESULTS: Plasma P-LLF (+23%, p = 0.001) was significantly higher and plasma oxLDL-4E6 (-33%, p <0.001) and apolipoprotein B (apoB) (-30%, p <0.001) concentrations were significantly lower in men with CAD compared with controls. Plasma P-LLF concentration was correlated significantly with plasma apoB (r = -0.596, p <0.001), serum albumin (r = 0.518, p <0.001), and age (r = 0.390, p = 0.009) and these variables were independent predictors of P-LLF in the study population. Plasma P-LLF was no longer significantly higher in men with CAD when plasma apoB concentration was taken into account. CONCLUSIONS: Plasma P-LLF concentration is abnormally high and appears to be closely associated with lower levels of apoB in men with CAD receiving statin therapy. ApoB may be a preferential target of reactive aldehydic lipid oxidation products and a decrease in apoB may increase the quantity of these products available for condensation with albumin.

The redox state of glutathione in erythrocytes of individuals with Down syndrome.

BACKGROUND: The redox state of glutathione has been used as indicator for the redox environment of the cell. OBJECTIVES: To investigate relationships between the redox environments, the SOD activity, total antioxidant status and the oxidation stress markers production (MDA and lipofuscin). METHODS: Individuals with Down syndrome and age-matched healthy controls were enrolled into a study. Some parameters of oxidative stress in serum were determined: reduced glutathione, oxidized glutathione, redox potential of this couple (Eh), activity of superoxide dismutase in the red blood cells as well as malondialdehyde and lipofuscin. RESULTS: In the group of persons with DS statistically significant decrease in the GSH concentration was found, however, no differences in the GSSG concentration versus controls was observed. The redox potential values for couple GSH/GSSG are a statistically significantly increased in DS individuals compared to controls. CONCLUSION: In this study we highlighted the different ways of view at the role of GSH in metabolism of persons with DS. It is useful to look at the GSH and GSSG concentrations separately as well as at redox potential value, which influence total redox state of organism (Tab. 2, Fig. 3, Ref. 30) Full Text (Free, PDF) www.bmj.sk.

Lipofuscin, homocysteine and tissue polypeptide specific antigen in gestational hypertension.

OBJECTIVE: The aim of this study were to assess the levels of lipofuscin (parameter of oxidative stress), homocysteine (as a marker of vascular injury) and tissue specific antigen - TPS - (as a marker of cell proliferation) in relation to arterial pressure of pregnant woman. STUDY DESIGN: Healthy pregnant women (n=18), women with mild 140/90=< RR<160/100 (n=19), and severe 160/100=

Hypochlorous acid and 3,4-dihydroxyphenylalanine increase the formation of serum protein lipofuscin-like fluorophores in vitro.

INTRODUCTION: Serum protein lipofuscin-like fluorophores (LLFs) that include fluorescent advanced glycation end products (AGEs), are an index of protein modification and levels are abnormally high in hemodialysis patients. To investigate the possibility that hypochlorous acid (HOCl) and 3,4-dihydroxyphenylalanine (DOPA) may contribute to high LLFs concentrations, we have examined the effect of these factors on serum protein LLF formation in vitro. METHODS: Protein LLF concentration was measured at excitation 350 nm and emission 460 nm and was expressed in arbitrary units relative to quinine sulphate fluorescence. Oxidation of serum or other solutions with HOCl was carried out at room temperature for 30 minutes and serum was delipidated before measurement of protein LLFs. RESULTS: Serum protein LLF concentration increased non-linearly by a maximum 247% with increasing HOCl concentration in the range 6.5-32.9 mmol/L and this was mirrored by a decrease in protein tryptophan fluorescence. HOCl (32.9 mmol/L) increased LLFs in human gamma-globulin solutions (15-fold in 12 mg/mL and 5-fold in 60 mg/mL solutions) and did not alter LLFs appreciably in human serum albumin solution (60 mg/mL). Addition of DOPA (265 micromol/L) significantly (P<0.001) increased LLF formation in serum by nearly 2-fold during 3 days incubation under air. CONCLUSIONS: These data suggest that HOCl and DOPA are capable of generating serum protein LLFs and that gamma-globulins appear to be an important substrate for protein LLF formation in human serum. These findings may be relevant to the abnormally high concentrations of serum protein LLFs and impaired immune response in hemodialysis patients.

[Serum lipofuscin level after renal transplantation]. / Stezenie lipofuscyny w surowicy po przeszczepie nerki.

BACKGROUND: Lipofuscin is believed to be the last product of lipid peroxidation. Elevated serum lipofuscin in chronic renal insufficiency and in multiple organ failure after major surgery has been detected. AIM: To compare serum lipofuscin level after renal transplantation with hemodialysed patients and healthy adults. MATERIAL AND METHODS: Lipofuscin has been determined according to Tsuchida with Roumen's modification and expressed in arbitrary units (u.), in serum of 56 healthy adults, 11 renal transplant recipients and nine hemodialysed patients. Blood was collected before hemodialysis in uremic patients, or within 24 h after renal transplantation. RESULTS: Serum lipofuscin in hemodialysed patients and renal recipients was significantly higher about 80% and 180% respectively, comparing to healthy adults. CONCLUSION: Elevated serum lipofuscin levels after renal transplantations show high oxidative stress due to several mechanisms of lipid peroxidation in this group of patients.

An assessment of docosahexaenoic acid intake from the viewpoint of safety and physiological efficacy in matured rats.

BACKGROUND/AIMS: In order to clarify an appropriate intake of docosahexaenoic acid (DHA, 22:6n-3), from the viewpoint of safety and physiological efficacy, the potential changes in lipid peroxidation and antioxidant defense in serum and tissues as well as those in serum lipid levels were examined in matured rats at the age of 1 year. METHODS: Rats were given the diets containing graded levels of purified DHA (0, 1.0, 3.1 and 8.4% of total energy, en%) for 30 days (control and 1.0, 3.1 and 8.4 en% groups). Lipid peroxides and alpha-tocopherol levels in serum and tissues, and lipid levels in serum were measured. RESULTS: Serum alpha-tocopherol concentrations in the 3.1 and 8.4 en% groups were significantly lower than those in the control group. Liver lipid peroxide levels assessed using the microsomal conjugated dienes were significantly higher in the 3.1 and 8.4 en% groups than those in the control group, and the chemiluminescence intensity and thiobarbituric acid value were significantly greater in the 8.4 en% group than in the control group. The liver alpha-tocopherol level decreased in response to the increases in lipid peroxide levels, but a significant difference was recognized only in the 8.4 en% group. In the kidney, no changes in lipid peroxide levels were observed, but the alpha-tocopherol level was significantly lower in the 8.4 en% group than in the control group. The levels of all the serum lipids including total cholesterol, HDL-cholesterol, triacylglycerols and phospholipids decreased as the dietary DHA level increased, and total cholesterol and phospholipid concentrations were significantly lower in the 3.1 and 8.4 en% groups than in the control group. CONCLUSION: These experimental results suggest that the dietary intake of DHA should not be more than 3 en% in matured rats to avoid the potentially chronic deleterious influences caused by lipid peroxidation in serum and tissues, and that the amelioration of serum lipid levels is recognized in rats fed DHA at 3 en% and above.

A multiantioxidant supplementation reduces damage from ischaemia reperfusion in patients after lower torso ischaemia. A randomised trial.

BACKGROUND: open repair of intra-abdominal aortic aneurysm (AAA) is associated with lower torso ischaemia and reperfusion. OBJECTIVE: to examine the effect of antioxidants on the activation and sequestration of white blood cells and muscle injury during AAA repair. METHOD: forty-two patients undergoing elective infrarenal aneurysm repair, were randomised to either standard therapy (22 patients) or standard therapy with additional multiantioxidant supplementation (20 patients). Vitamin E and C, Allopurinol, N-acetylcysteine and mannitol was administered perioperatively. White blood cell count (WBC), serum creatine kinase, aspartateaminotransferase, lactate and lipofuscine were measured. RESULTS: WBC remained higher after reperfusion in the antioxidant group (p = 0.008). CK, ASAT and lipofuscine levels were significantly lower after reperfusion in the antioxidant group (p = 0.02, p = 0.018, p = 0.017). CONCLUSION: multi-antioxidant supplementation was associated with a reduction in serum CK and ASAT after AAA repair. This is likely due to a reduction in oxidative stress and a decreased leucocyte sequestration and activation.

[Changes in serum levels of lipid peroxidation products during labor and in the puerperium]. / Zmeny sérových hladín produktov lipoperoxidácie pocas pôrodu a v sestonedelí.

OBJECTIVE: To determine the activity of reactive oxygen species (ROS) during labour by characterizing changes in maternal serum levels of lipid peroxidation end-products--MDA and lipofuscin during labour and the early post-partum period. We also tried to evaluate the relationship between levels of lipid peroxides and some clinical characteristics of labour. DESIGN: Prospective study. SETTING: Department of Obstetrics and Gynaecology LFUK, Bratislava; Department of clinical laboratories, Ministry of defense SR, Bratislava. METHODS: Blood samples were obtained from 66 pregnant women with uncomplicated pregnancy at the end of labour and during the early post-partum period. The control group consisted of 19 pregnant women delivering by primary Cesarean section. Blood samples were examined for MDA and lipofuscin by HPLC method. We used paired and unpaired Student's t-test to statistically evaluate our results. RESULTS: MDA and lipofuscin levels in pregnant women delivering spontaneously compared to those delivering by C-section were significantly elevated (P < 0.05). MDA and lipofuscin levels in pregnant women during spontaneous labour or during by C-section compared to the levels in early post-partum period were not significantly increased. We have not found any correlation between the length of the labour and lipoperoxides concentration.

[Increased levels of circulating advanced glycation end products in a model of acute renal insufficiency in rats]. / Zvýsenie koncentrácií cirkulujúcich koncových produktov pokrocilej glykácie v modeli akútnej renálnej insuficiencie u potkana.

BACKGROUND: Advanced glycation end products (AGEs) are formed from proteins and peptides by non-enzymatic glycation or glycooxidation. AGEs are formed slowly during aging, and they accumulate in circulation and tissues in diabetes and chronic renal failure. Kidney plays a key role in the disposal of AGEs. Aim of this study was to verify the hypothesis that, acute loss of renal function with enhanced oxidative and carbonyl stress should result in a rise of circulating AGEs levels. METHOD AND RESULTS: Acute renal failure (ARI) was induced in rats by bilateral nephrectomy (24-72 hours). The data on AGEs levels, oxidative status and antioxidative defense was compared to those of sham operated animals. 48 hours after the induction of ARI concentrations of AGEs, determined fluorimetrically or as carboxymethyllysine, rose 2-fold, and they correlated with concentrations of creatinine (r = 0.938, p < 0.001 and r = 0.815, p < 0.001, respectively). Malondialdehyde (MDA) and lipofuscine (LF) concentrations rose in a time dependent manner, suggesting an enhanced oxidative and carbonyl stress. Enhanced lipid peroxidation did not result from the suppressed antioxidant defense: activity of superoxide dismutase rose by 50%, while that of glutathione peroxidase was not compromised. Total antioxidant status increased, probably due to the accumulation of uremic toxins with scavenging capacity, such as hyppurate. CONCLUSIONS: According to our knowledge our data was first to show a rapid increase in circulating AGEs concentrations in the model of acute renal failure in rats. If AGEs accumulate in acute renal failure in humans, their contribution to acute toxicity, and/or to the development of later complications, might be of a great importance.

Circulating advanced glycation end product levels in rats rapidly increase with acute renal failure.

BACKGROUND: Advanced glycation end products (AGEs) are formed on proteins and peptides slowly during aging, and they accumulate in circulation and tissues in diabetes and chronic renal failure. Except for nonenzymatic glycation, enhanced oxidative/carbonyl stress is supposed to participate in their formation. The kidney plays a key role in disposal of AGEs, particularly AGE-peptides. We assumed that even a short time combination of enhanced oxidative/carbonyl stress and a lack of renal function should result in elevation of circulating AGE levels. METHOD: To verify this hypothesis, two models of acute renal failure in rats, bilateral nephrectomy and bilateral ureteral ligation, were employed, and the data were compared with those of sham-operated animals. RESULTS: AGE levels determined fluorimetrically or as carboxymethyllysine concentration rose by a factor of three within 48 hours. Enhanced levels of malondialdehyde and lipofuscin pointed to an enhanced oxidative/carbonyl stress. Activity of antioxidant enzymes such as superoxide dismutase and glutathione peroxidase were not compromised, or were even elevated, respectively. Total antioxidant status increased, probably as a consequence of an accumulation of indols and benzoic acid derivatives, uremic toxins with scavenging capacities, as shown for hippurate. CONCLUSIONS: Evidence was given that circulating AGEs in the model of acute renal failure in rats undergo a substantial rise within a short time period. A source of increased AGEs is not clear, since except for the lack of the kidney function, accelerated synthesis of AGEs under enhanced oxidative/carbonyl stress as well as liberation of AGEs from tissues due to protein catabolism might be anticipated. If AGEs accumulate in acute renal failure in humans, their contribution to acute toxicity, or of the development of the complications later, might be of importance.

Plasma levels of advanced glycation end products in children with renal disease.

In adults, advanced glycation end products (AGEs) rise slowly in tissues and circulation during aging, and accumulate at an accelerated rate both in diabetes and chronic renal insufficiency (CRI). We aimed to investigate the pattern of AGE accumulation in children/adolescents with CRI and on renal replacement therapy by dialysis and transplantation. Concentrations of fluorescent AGEs, carboxymethyllysine (CML) and lipofuscin-like substance (LFLS, a marker of lipid peroxidation) were followed. Data were obtained from 11 CRI patients on conservative treatment (age 12.6+/-1.7 years, serum creatinine: 205.7+/-17.5 micromol/l), ten patients on renal replacement therapy with dialysis (13.6+/-1.7 years, 698.2+/-48.9 micromol/l) and nine patients after kidney transplantation (15.9+/-1.1 years, 115.9+/-12.0 micromol/l) and comparison made with the data from 28 healthy controls (11.8+/-8.2 years, 44.1+/-8.2 micromol/l). In controls, an age-dependent rise of fluorescent AGE and CML levels was observed. In the CRI group, fluorescent AGEs [0.38+/-0.03x105 arbitrary units (AU)] and CML (369+/-26 ng/ml) concentrations were doubled compared with controls (0.16+/-0.03x105 AU and 189+/-42 ng/ml, respectively) and even higher levels were revealed in dialyzed patients (0.80+/-0.05x105 AU; 650+/-94 ng/ml). Successful kidney transplantation significantly reduced but did not normalize fluorescent AGE levels (0.39+/-0.03 x105 AU), while the decline in CML levels (550+/-47 ng/ml) was insignificant. Plasma LFLS was elevated in CRI (19.6+/- 1.7 AU) and was even higher in dialyzed children (32.0+/-5.3 AU) compared with healthy controls (7.1+/- 1.4 AU). Kidney transplantation did not normalize LFLS levels (20.3+/-5.3 AU), pointing to persistently enhanced lipid peroxidation. Our study provides the first data on enhanced fluorescent AGEs and CML levels in children/adolescents with CRI and on dialysis. Successful renal transplantation decreased but did not normalize AGE levels, probably because of still-impaired renal function with enhanced oxidative stress, as well as the influence of immunosuppressive therapy.

The probable involvement of soluble and deposited melanins, their intermediates and the reactive oxygen side-products in human diseases and aging.

The plasma soluble melanins (PSM) form spontaneously in vitro and in vivo and their formation involves oxidative polymerization and copolymerization of dopa, catecholamines, homogentisic acid, 3-hydroxyanthranilic acid, p-aminophenol, p-phenylenediamine, and other end(ex)ogenous ortho and para polyhydroxy-, (poly)hydroxy(poly)amino- and polyamino-phenyl compounds. The build up of PSM is visible within 2-3 h after the start of incubation at 37 degrees C with 1 mg/ml of plasma. PSM also form similarly in blood and these processes cause hemolysis. The mean quantity of PSM in normal human plasma is 1.61+/-0.1 (S.D.) mg/ml (n = 20) and in normal human urine is 1.1+/-1.2 g/24 h collection (n = 8). They contribute to the yellow color of plasma and urine. Antioxidants delay the formation of PSM. The deposited melanins also form from these precursors. Reactive oxygen side products (ROSP) are generated during and after melanogenesis. Melanins in vivo are generally associated with proteins or with proteins and lipids. The PSM-protein-lipid complexes are called plasma soluble lipofuscins (PSL), because they have histochemical and fluorescence properties similar to those of solid lipofuscins. The soluble and deposited melanins (SDM) and their intermediates have similar toxic chemical reactivities. The oxidizing quinoid (they can produce partially and completely substituted conjugates) and the semiquinoid free radical intermediates are also moieties in most human melanin structures. Soluble melanins formed from dopa, or dopamine, or norepinephrine in weak alkaline solution have been shown to be toxic to human CD4+ lymphoblastic cells (MT-2) at higher than 10 microg/ml concentrations. Alkaptonuria with high levels of homogentisic acid in the plasma is a potentially fatal disease, exhibiting the toxic effects of the homogentisic acid melanin (soluble and deposited), its intermediates and the ROSP. Patients with alkaptonuria develop arthritis and often suffer from other diseases too, including cardiovascular disease (frequent cause of death) and kidney disease. Pheochromocytoma, with high levels of catecholamines in the plasma is another potentially fatal disease. The catecholamine PSM of pheochromocytoma have very light yellow or practically no colors, due to the concentrations and chemical structures. Pheochromocytomas can cause hypertension, cardiovascular disease (frequent cause of death), kidney disease, stroke, cancer, amyloid formation and can mimic many other diseases, including acute pancreatitis, carcinoid, neuroblastoma, psychiatric illness, hypercalcemia, retinal vascular lesions, and diabetes mellitus. Pheochromocytoma is potentially fatal even in patients without hypertension. Following trauma and surgery, heavily pigmented eyes are apt to experience greater inflammation than lightly pigmented eyes. In Parkinson's disease those neurons are lost first in the substantia nigra and locus ceruleus which contain the greatest amounts of neuromelanins. The antihypertensive alphamethyldopa causes Parkinson's syndrome. It forms PSM in a short time in vitro. The side effects of L-dopa (immobility episodes alternate with normal or involuntary movements; psychotic abnormalities) suggest that the SDM, their intermediates and the ROSP present naturally in vivo are involved in the cause of Parkinson's disease and Alzheimer's disease. There is a large overlap between these two diseases. (ABSTRACT TRUNCATED)

[The value of lipofuscin determination in blood at the pathophysiologic clinic--literature review]. / Wartosc oznaczania lipofuscyny we krwi w patofizjologii klinicznej--przeglad pismiennictwa.

Lipofuscin is a conjugated Schiff base delivered from reaction of malonylodialdehyde with proteins, amino acids and phosphatidylethanolamines. It emits yellow-green autofluorescence in ultraviolet light. It is believed to be one of the parameters of oxidation stress in vivo. Increased amount of lipofuscin in the blood has been found in uremia, diabetes, aging process, adult respiratory distress syndrome and multiple organ failure.

Malondialdehyde, lipofuscin and activity of antioxidant enzymes during physical exercise in patients with essential hypertension.

DESIGN: To clarify the role of oxidative damage in essential hypertension, levels of lipid peroxidation products (malondialdehyde and lipofuscin) and activity of antioxidant enzymes (superoxide dismutase and glutathione peroxidase) were examined during a short period of physical exercise. PATIENTS AND METHODS: We studied 11 male patients with mild to moderate essential hypertension in World Health Organization classes I or II and 10 healthy male controls. Physical exercise was performed on a bicycle ergometer at graded intensities of 1.0, 1.5 and 2.0 W/kg body weight Plasma concentrations of lipofuscin, malondialdehyde, epinephrine, norepinephrine, insulin, free fatty acids and glucose were determined. Superoxide dismutase activity was analysed in erythrocytes and glutathione peroxidase activity in whole blood. RESULTS: Concentrations of lipofuscin and malondialdehyde were significantly elevated in hypertensive patients. Superoxide dismutase activity was not different between groups, while glutathione peroxidase activity was significantly decreased in hypertensive subjects. During exercise, the concentration of malondialdehyde and antioxidant enzyme activities increased significantly in both groups. No differences were found in absolute increases between the normotensive and hypertensive subjects. The levels of glucose, insulin and free fatty acids were similar in both groups. Basal concentrations of catecholamines and also the exercise-induced increases were lower in hypertensive patients. CONCLUSIONS: Our results indicate increased oxidative damage in patients with essential hypertension, which might be caused by a decrease in the activity of glutathione peroxidase. The ability of superoxide dismutase and glutathione peroxidase to respond to increased production of reactive oxygen species during a short period of physical exercise was not impaired in hypertensive subjects.