cysteinyldopa and glutathionyldopa

Laparoscopic colorectal surgery causes a lower stress response than open surgery. Adiponectin is mainly derived from adipocytes and has antidiabetic, antioxidative, and anti-inflammatory capabilities. The objective of the present study was to investigate the protein expression of adiponectin in adipose tissue, and the serum levels of adiponectin, oxidative stress markers and proinflammatory factors during laparoscopic colorectal surgery and open surgery periods.. Forty patients aged 60 to 80, with American Society of Anesthesiologists (ASA) I ~ II who underwent radical resection of colorectal cancer were recruited to the study. Laparoscopic group and open group included 20 patients each. Mesenteric adipose tissue and venous blood before (T1) and at the end (T2) of surgery were collected to examine adiponectin levels, and venous blood was collected to examine serum levels of oxidative stress related markers (superoxide dismutase (SOD), glutathione (GSH), lipid peroxide (LPO), malondialdehyde (MDA)), and inflammation-related factors (interleukin (IL)-1β, interleukin (IL)-6, tumor necrosis factor-α (TNF-α)).. Protein and serum levels of adiponectin were analyzed, and adiponectin levels were significantly increased at T2 than T1 in the laparoscopic surgery, while adiponectin levels were significantly higher in the laparoscopic surgery than in the open surgery at T2. In addition, the serum levels of SOD and GSH were significantly higher in the laparoscopic surgery than in open surgery at T2. However, the serum levels of LPO, TNF-α, IL-1β, and IL-6 were significantly lower in the laparoscopic group than in open group at T2.. Laparoscopic surgery induced higher levels of adiponectin in both adipose tissue and the bloodstream. Oxidative stress and the inflammatory response were lower during laparoscopic colorectal surgery than during conventional open surgery. These data suggest that adipose tissue may alleviate the stress response during laparoscopic surgery by releasing adiponectin in patients with colorectal cancer.

Topics: Adiponectin; Adipose Tissue; Aged; Aged, 80 and over; Biomarkers; Colorectal Neoplasms; Cysteinyldopa; Female; Glutathione; Humans; Laparoscopy; Lipid Peroxides; Male; Middle Aged; Oxidative Stress; Stress, Physiological; Superoxide Dismutase

Ameliorative effects of few naturally occurring antioxidants like ascorbic acid (vitamin C), alpha-tocopherol (vitamin E) either alone or in combination with meso-2,3-dimercaptosuccinic acid (DMSA) or monoisoamyl DMSA (MiADMSA), on parameters indicative of oxidative stress in the liver, kidney, brain and blood of lead-exposed rats were studied. Male Wistar rats were exposed to 0.1% lead acetate in drinking water for 3 months and treated thereafter with DMSA or its analogue MiADMSA (50 mg/kg, intraperitoneally), either individually or in combination with vitamin E (5 mg/kg, intramuscularly) or vitamin C (25 mg/kg, orally) once daily for 5 days. The effects of these treatments in influencing the lead-induced alterations in haem synthesis pathway, hepatic, renal and brain oxidative stress and lead concentration from the soft tissues were investigated. Exposure to lead produced a significant inhibition of delta-aminolevulinic acid dehydratase (ALAD) activity from 8.44+/-0.26 in control animals to 1.76+/-0.32 in lead control, reduction in glutathione (GSH) from 3.56+/-0.14 to 2.57+/-0.25 and an increase in zinc protoporphyrin level from 62.0+/-3.9 to 170+/-10.7 in blood, suggesting altered haem synthesis pathway. Both the thiol chelators and the two vitamins were able to increase blood ALAD activity towards normal, however, GSH level responded favorably only to the two thiol chelators. The most prominent effect on blood ALAD activity was, however, observed when MiADMSA was co-administered with vitamin C (7.51+/-0.17). Lead exposure produced a significant depletion of hepatic GSH from 4.59+/-0.78 in control animals to 2.27+/-0.47 in lead controls and catalase activity from 100+/-3.4 to 22.1+/-0.25, while oxidized glutathione (GSSG; 0.34+/-0.05 to 2.05+/-0.25), thiobarbituric acid reactive substance (TBARS; 1.70+/-0.45 to 5.22+/-0.50) and glutathione peroxidase (GPx) levels (3.41+/-0.09 to 6.17+/-0.65) increased significantly, pointing to hepatic oxidative stress. Altered, reduced and oxidized GSH levels showed significant recovery after MiADMSA and DMSA administration while, vitamins E and C were effective in reducing GSSG and TBARS levels and increasing catalase activity. Administration of MiADMSA alone and the combined administration of vitamin C along with DMSA and MiADMSA were most effective in increasing hepatic GSH levels to 4.88+/-0.14, 4.09+/-0.12 and 4.30+/-0.06, respectively. Hepatic catalase also reached near normal level in animals co-administered v

Topics: Animals; Antidotes; Antioxidants; Ascorbic Acid; Chelating Agents; Cysteinyldopa; Disease Models, Animal; Drug Therapy, Combination; Lead Poisoning; Male; Oxidative Stress; Porphobilinogen Synthase; Protoporphyrins; Rats; Rats, Wistar; Succimer; Treatment Outcome; Vitamin E

Human glutathione transferase M2-2 prevents the formation of neurotoxic aminochrome and dopachrome by catalyzing the conjugation of dopamine and dopa o-quinone with glutathione. NMR analysis of dopamine and dopa o-quinone-glutathione conjugates revealed that the addition of glutathione was at C-5 to form 5-S-glutathionyl-dopamine and 5-S-glutathionyl-dopa, respectively. Both conjugates were found to be resistant to oxidation by biological oxidizing agents such as O(2), H(2)O(2), and O(*-)(2), and the glutathione transferase-catalyzed reaction can therefore serve a neuroprotective antioxidant function.

Topics: Benzoquinones; Cysteinyldopa; Dihydroxyphenylalanine; Dopamine; Glutathione; Glutathione Transferase; Humans; Indolequinones; Indoles; Isoenzymes; Magnetic Resonance Spectroscopy; Models, Chemical; Oxidation-Reduction; Protein Binding; Quinones; Time Factors

Recent advances in the study of the molecular biology of mouse pigmentation have led to the discovery of a family of proteins involved in the control of melanin synthesis. It has been confirmed that the product of the mouse c (albino) locus is the key melanogenic enzyme tyrosinase, but study of its function and regulation have been hampered by the presence of closely related proteins within melanin-synthesising cells. To overcome these problems, we have established lines of mouse fibroblasts expressing the c locus mouse tyrosinase. Here we describe characterisation of the tyrosinase synthesised by these cells and demonstrate considerable similarity between the expressed tyrosinase and the native enzyme. The expressed tyrosinase is proteolytically cleaved to produce membrane-bound and soluble forms of the expected molecular mass and is rich in N-linked carbohydrate, suggesting that melanocytic differentiation is not a prerequisite for post-translational modification of the protein. The expressed enzyme has tyrosinase activity, but not catalase or dopachrome tautomerase activity, confirming that it is an authentic tyrosinase. Transfected fibroblasts expressing tyrosinase are shown to share several physiological characteristics with melanoma cell lines, including increased pigmentation and tyrosinase activity in response to increased cell density. Since tyrosinase is expressed under a heterologous promoter, these shared characteristics probably reflect translational or post-translational controls that operate in both non-melanocytic and melanocytic cell types. We demonstrate that pigmented fibroblasts contain the melanin synthesis intermediates 5-S-cysteinyldopa and 5-S-glutathionyl-dopa, and produce a phaeomelanin-like pigment, but do not contain detectable eumelanin. Expression of tyrosine is therefore sufficient for the synthesis of a form of melanin pigment in fibroblasts.

Topics: 3T3 Cells; Animals; Catalase; Cysteinyldopa; Gene Expression Regulation, Enzymologic; Intramolecular Oxidoreductases; Isomerases; Melanins; Mice; Monophenol Monooxygenase; Pigmentation; RNA Splicing

The melanocyte activity was studied by analysis of the urinary excretion of indolic and cysteinyldopa compounds. One eumelanin marker, 5,6-dihydroxy-indole-2-carboxylic acid was identified and quantified in normal urine. However, its low concentration and sensitivity to oxidation made it less suitable for clinical studies. A methylated derivative of this substance, 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI-2-C), was also demonstrated in normal urine. A quantitative method was worked out and the normal urinary concentration of this substance was as high as the concentration of 5-S-cysteinyldopa. The concentrations of the eumelanic marker 6-hydroxy-5-methoxyindole-2-carboxylic acid and the pheomelanic marker 5-S-cysteinyldopa were determined in the urine of psoriasis patients during PUVA treatment and also in the urine of subjects with different skin colour. The melanocyte activity in albinotic patients and in albinotic mice was studied by the same technique. Some in vitro experiments were performed to show that 5-S-glutathionyldopa has the molecular properties of forming a mercapto-substituted indole derivative. The following main conclusions were drawn: 1. 5,6-Dihydroxyindole-2-carboxylic acid and 6-hydroxy-5-methoxyindole-2-carboxylic acid are both present in measurable amounts in normal urine. 2. The urinary concentration of 6-hydroxy-5-methoxyindole-2-carboxylic acid increased during PUVA treatment in a similar way as for 5-S-cysteinyldopa. 3. The eumelanic marker 6-hydroxy-5-methoxyindole-2-carboxylic acid was excreted in larger quantities by people with genetically dark skin, whereas the pheomelanic marker 5-S-cysteinyldopa was not related to pigment type. 4. In the urine of one albino patient and in the urine of albinotic mice a total absence of 6-hydroxy-5-methoxyindole-2-carboxylic acid was found. The urinary concentrations of 5-S-cysteinyldopa in these subjects were measurable but lower than in pigmented subjects. Thus, 6-hydroxy-5-methoxy-indole-2-carboxylic acid seems to be a more specific melanocyte marker than the cysteinyldopas.(ABSTRACT TRUNCATED AT 400 WORDS)

Topics: Albinism; Animals; Biomarkers; Cysteinyldopa; Humans; Indoles; Melanocytes; Mice; Oxidation-Reduction; Pigmentation; PUVA Therapy

The concentrations of dopa, cysteinyldopas, 5-S-glutathionyldopa, gamma-glutamyl-5-S-cysteinyldopa and 5-S-cysteinylglycinedopa, were analysed in homogenates of cultured human melanoma cells and in culture media. Cysteinyldopas were found to be the major catechol in the cells, with a molar concentration more than a hundred times that of dopa. 5-S-Glutathionyldopa was found in the same amount as dopa, while the quantity of 5-S-cysteinylglycinedopa was one order of magnitude less. gamma-Glutamyl-5-S-cysteinyldopa was not present in detectable amounts. In the medium the concentrations of dopa, 5-S-cysteinylglycinedopa and of 5-S-glutathionyldopa were about one half of those in the cells, while the concentration of cysteinyldopas was about 2%. The ratio between 2-S-cysteinyldopa and 5-S-cysteinyldopa when incubating dopa and cysteine with tyrosinase was identical with the ratio between the analogically synthetised isomers of glutathionyldopa. Consequently, from the calculation of these ratios in cells and media one cannot deduce whether cysteinyldopas arise from the direct addition of cysteine to dopaquinone, or from degradation of glutathionyldopa. Oxidation of 5-S-glutathionyldopa gives a red chromophore with maximum absorption at 480 nm which develops into a black pigment.

Topics: Benzoquinones; Cell Line; Cysteinyldopa; Dihydroxyphenylalanine; Humans; Melanoma; Pigmentation

5-S-Glutathionyldopa is oxidized at incubation with tyrosinase and dopa producing a black pigment. The reaction proceeds with the formation of two chromophores with absorption spectra similar to those of dopachrome and melanochrome, respectively. Zn2+ catalyses the formation of the melanochrome-like compound. The oxidation of 5-S-glutathionyldopa by dopaquinone, formed by the action of human tyrosinase and mushroom tyrosinase, is considerably slower than that of 5-S-cysteinyldopa. The higher oxidation potential of 5-S-glutathionyldopa, and/or the greater number of dopaquinone molecules necessary for pigment formation from 5-S-glutathionyldopa and/or the formation of tyrosinase-inhibiting products from 5-S-glutathionyldopa can explain the slower oxidation of this compound. The oxidative pathways suggested for 5-S-glutathionyldopa by the present findings may be relevant both in the melanocyte and in non-specific oxidation of cathechols occurring in other cells.

Topics: Basidiomycota; Cell Line; Ceruloplasmin; Cysteinyldopa; Dihydroxyphenylalanine; Humans; Hydroxydopamines; In Vitro Techniques; Melanoma; Monophenol Monooxygenase; Oxidation-Reduction; Spectrophotometry

A convenient method is described for the preparation of 5-S- and 2-S-glutathionyldopa, based on tyrosinase oxidation of dopa in the presence of glutathione. The yields of 5-S, 2-S, and 6-S isomers produced were about 76, 12, and 5%, respectively.

Topics: Cysteinyldopa; Dihydroxyphenylalanine; Glutathione; Isomerism; Monophenol Monooxygenase

Topics: Adolescent; Adult; Aged; Antineoplastic Agents; Combined Modality Therapy; Cysteinyldopa; Dacarbazine; Dihydroxyphenylalanine; Female; Humans; Immunotherapy; Male; Melanoma; Middle Aged; Nimustine; Nitrosourea Compounds; Prognosis; Vincristine

Topics: Albinism; Animals; Cattle; Choroid; Chromatography, High Pressure Liquid; Cysteinyldopa; Dihydroxyphenylalanine; Kidney; Rats; Retinal Pigments; Skin; Spleen