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PubMedDate not supplied

Blood storage XXIV: red blood cell 2,3-DPG and ATP maintenance for six weeks in CPD-adenine with higher phosphate, pyruvate, and dihydroxyacetone.

The individual and collective effects of various phosphate, pyruvate and dihydroxyacetone concentrations on 2,3-DPG and ATP maintenance during blood storage with CPD-adenine (0.25 mM), were studied. Phosphate concentrations ranged from 2 to 100 mM. Low concentations were best for 2,3-DPG maintenance during the first three weeks, after which there was no difference. ATP concentrations were better maintained by the highest phosphate concentrations in the first week. After the second week the lower concentrations of phosphate were better. With pyruvate 40 and 60 mM were the best for 2,3-DPG levels through six weeks of storage. ATP concentrations were poorest with high pyruvate. Maintenance of 2,3-DPG was above half normal for six weeks of storage in the 60, 80 and 100 mM DHA preservatives. ATP concentrations were best maintained in the preservative lacking DHA. Combinations of phosphate, pyruvate and DHA in concentrations which had been found to be effective when used individually were studied. Best maintenance of 2,3-DPG (above half normal levels) for six weeks was afforded by pyruvate, phosphate and DHA, and by pyruvate and DHA. ATP maintenance was best afforded by CPD-adenine alone and CPD-adenine with pyruvate and phosphate. Pyruvate alone maintained ATP less well and the pyruvate-DHA was worst. Intermediate in maintenance of ATP was the preservative containing pyruvate, phosphate and DHA.

Adenine↗
PubMedDate not supplied

The potential use of dihydroxyacetone for improved 2,3-DPG maintenance in red blood cell storage: solution stability and use in packed cell storage.

Dihydroxyacetone (DHA) is effective in maintaining 2,3-diphosphoglycerate (2,3-DPG) concentrations in stored red blood cells. One limitation to the use of DHA is its instability when added to anticoagulant solutions during blood bag manufacture. The stability of DHA solutions have been evaluated. Solutions of DHA are stable at 25 C in water or isotonic saline, with or without the addition of glucose or adenine. DHA is stable to autoclaving; 99 + per cent surviving at 150 mM, and 89 per cent surviving at 1.9 M concentrations. DHA can be incorporated into a satellite addition pouch attached to the main blood drawing bag, and be added to the blood-anticoagulant mixture after phlebotomy or the preparation of red blood cells. Addition of the DHA solution, containing adenine and extra glucose, to packed cells causes significantly improved maintenance of 2,3-DPG during 42 days of 4 C storage, while maintaining adequate concentrations of red blood cell ATP. The use of DHA, adenine, and glucose in extended storage of packed cells, using either zero or seven day addition of the nutrient solution, produces similar efficacious results.

Adenosine Triphosphate↗
PubMedDate not supplied

Dihydroxyacetone, pyruvate, and phosphate effects on 2,3 DPG and ATP in citrate-phosphate-dextrose-adenine blood preservation.

Blood was stored with various combinations of 60 mM dihydroxyacetone (DHA), 80 mM pyruvate and 10 mM phosphate in citrate-phosphate-dextrose-adenine-one (CPDA-1) preservative for 42 days. During that time, DHA was found to have a beneficial effect on 2,3 diphosphoglycerate (2,3 DPG), although a deleterious effect on adenosine triphosphate (ATP). Preservatives containing pyruvate gave similar results. However, DHA and phosphate together in CPDA-1 improved both 2,3 DPG and ATP. The adverse effect on 2,3 DPG levels that phosphate normally shows was reversed by the addition of DHA. These results indicate that the addition of phosphate alone, rather than pyruvate, or pyruvate and phosphate, to DHA in CPDA-1 would be preferable to the presently licensed CPDA-1 preservative.

2,3-Diphosphoglycerate↗
PubMed1993

Amino acid arterial concentration and muscle exchange during submaximal arm and leg exercise: the effect of dihydroxyacetone and pyruvate.

The mixture of dihydroxyacetone and pyruvate (DHAP) is an ergogenic aid that enhances muscle glucose extraction during prolonged aerobic exercise. In order to evaluate the effect of DHAP on muscle amino acid extraction during exercise, we measured arterial concentration and muscle exchange of amino acids in 18 untrained healthy male subjects (aged 20-30 years) performing dynamic arm (60% VO2 max, n = 9) or leg (70% VO2 max, n = 9) exercise to exhaustion with and without dietary supplementation of DHAP. The subjects consumed diets (146 kJ kg body weight-1 day-1) containing either 100 g polyglucose, Polycose (placebo, P) or DHAP (3:1, treatment) substituted for a portion of carbohydrate. The two diets were administered in a double-blind, random, crossover order for a 7-day period. At least 7 days separated the dietary protocols. Blood samples were drawn through radial artery and axillary or femoral vein catheters at rest, during exercise and at exhaustion. Arterial alanine concentration increased by 30% during arm exercise and by 50-60% during leg exercise. No other arterial amino acid concentration changed during exercise. At exhaustion, arterial alanine concentration decreased to pre-exercise levels with arm exercise but remained elevated after leg exercise. Despite changes in arterial concentrations of alanine with exercise, muscle exchange of alanine was not altered with exercise. Exercise did not alter muscle exchange of any amino acid. Arterial amino acid concentrations and muscle exchange of amino acids with exercise were similar with or without DHAP feeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2007

Repeated use of immobilized Gluconobacter oxydans cells for conversion of glycerol to dihydroxyacetone.

Dihydroxyacetone (DHA) is of great interest in the fine chemical and pharmaceutical industry; therefore, the discovery of suitable biocatalysts for the efficient production of it is very necessary. In the experiment, Gluconobacter oxydans was immobilized in polyvinyl alcohol (PVA). Various parameters of the immobilized cells were investigated. The results have shown that the optimal conversion conditions by the immobilized cells were at 30 degrees C and pH 6.0. The immobilized cells remained very active over the period of 14 days for storage and only lost 10% of its original activity. Repeated use of immobilized cells for conversion of glycerol to DHA was carried out in a 1.5 L stirred tank reactor, the average conversion rate was about 86%. Despite the high shear stress, bead shape was not affected, even after five consecutive conversion cycles. The regenerated biocatalyst could recover 90% of its initial activity.

Bioreactors↗
PubMed1981

Red cell ATP and 2,3-diphosphoglycerate concentrations as a function of dihydroxyacetone supplementation of CPD adenine.

Units of CPDA-1 whole blood were subdivided and each treated with additions of dihydroxyacetone (DHA) to give final concentrations from 0 to 80 mM. The 'optimum' concentration of DHA to maintain 2,3-diphosphoglycerate (2,3-DPG) with minimal loss of ATP during 42 days of storage appeared to be 30 mM of DHA. With this formulation, red cell 2,3-DPG concentrations rose to 130-140% of normal by 14 days and then decreased in a near-linear manner to 50-60% normal by 42 days, while maintaining adequate ATP levels. In addition, packed red cells were prepared form CPD fresh blood and treated with adenine, glucose, and various concentrations (0-80 mM) of DHA. The cells also responded most favorably to 30mM DHA, although the response was not as positive as whole blood. This concentration of DHA produced nearly 100% maintenance of 2,3-DPG at 14 days with subsequent fall to 30% of normal by 42 days.

2,3-Diphosphoglycerate↗
PubMed1977

Dihydroxyacetone reductase from Mucor javanicus. 1. Isolation and properties.

An NADPH-dependent oxidoreductase has been extracted from the mycelium of the fungus Mucor Javanicus (Wehmer) and enriched 1000-fold with respect to the protein contained in the crude extract after centrifugation at 2600 X g. The molecular weight of the enzyme was estimated by gel filtration to be about 100 000; electrophoresis under dissociating conditions indicates four subunits of molecular weight about 28 000. Data on stability and activity of the enzyme as a function of pH and temperature are reported. From a kinetic study and product analysis of the reduction of the two enantiomeric trans-1-decalones and also from a kinetic study of the oxidation of the two diastereomeric pairs of trans-1-decalols it follows that the enzymes is an e-Si oxidoreductase (according to the nomenclature proposed by Dutler et al., Eur. J. Biochem. 22 [1971]203-212 and Prelog and Helmchen, Helv. Chim. Acta, 55 [1972] 2581-2598). This classification is amply confirmed by the kinetic behaviour of a large number of alicyclic substrates. Using (4-2HSi-labelled coenzyme to reduce (9S)-trans-1,4-decalindione, it was shown that the enzyme is HSi (= HS = HB)-stereospecific with respect to the coenzyme. It is demonstrated that the oxidoreductase from Mucor javanicus can be used for the preparation of optically pure chiral alcohols and ketones. In the following paper evidence is presented that the natural substrate of the enzyme is dihydroxyacetone.

Alcohol Oxidoreductases↗
PubMed2004

Durability of the sun protection factor provided by dihydroxyacetone.

BACKGROUND/PURPOSE: The sunless tanning agent dihydroxyacetone (DHA) is known to protect against longwave ultraviolet radiation (UVA) and visible light. Recently, our laboratory has shown that DHA in addition offers a modest sun protection factor (SPF) in humans. We conducted this study in order to investigate the durability of the SPF provided by DHA. METHODS: Ten healthy volunteers were treated with 20% DHA cream twice in three areas on the volar forearm. One, 5 and 7 days after the second application the participants were phototested with simulated sunlight in each area. Blue reflectance was used to measure the skin coloration by DHA in the test sites. RESULTS: DHA generated a significant SPF of 3.0 at day 1, 2.0 at day 5 and 1.7 at day 7 (P<0.0001). The SPF was positively correlated to the change in blue reflectance (r=0.39, P=0.034). The loss of SPF unit/day was not significantly different between the subjects (P<0.122). However, the intercepts were significantly different (P<0.0001) indicating differences in the initial SPF obtained among the subjects. CONCLUSIONS: The SPF of DHA decreases with the same loss of SPF unit/day between humans and the durability of the SPF thus depends on the initial SPF provided.

Administration, Cutaneous↗
PubMed1978

Glycerolipid biosynthesis in Saccharomyces cerevisiae: sn-glycerol-3-phosphate and dihydroxyacetone phosphate acyltransferase activities.

Yeast acyl-coenzyme A:dihydroxyacetone-phosphate O-acyltransferase (DHAP acyltransferase; EC 2.3.1.42) was investigated to (i) determine whether its activity and that of acyl-coenzyme A:sn-glycerol-3-phosphate O-acyltransferase (glycerol-P acyltransferase; EC 2.3.1.15) represent dual catalytic functions of a single membranous enzyme, (ii) estimate the relative contributions of the glycerol-P and DHAP pathways for yeast glycerolipid synthesis, and (iii) evaluate the suitability of yeast for future genetic investigations of the eucaryotic glycerol-P and DHAP acyltransferase activities. The membranous DHAP acyltransferase activity showed an apparent Km of 0.79 mM for DHAP, with a Vmax of 5.3 nmol/min per mg, whereas the glycerol-P acyltransferase activity showed an apparent Km of 0.05 mM for glycerol-P, with a Vmax of 3.4 nmol/min per mg. Glycerol-P was a competitive inhibitor (Ki, 0.07 mM) of the DHAP acyltransferase activity, and DHAP was a competitive inhibitor (Ki, 0.91 mM) of the glycerol-P acyltransferase activity. The two acyltransferase activities exhibited marked similarities in their pH dependence, acyl-coenzyme A chain length preference and substrate concentration dependencies, thermolability, and patterns of inactivation by N-ethylmaleimide, trypsin, and detergents. Thus, the data strongly suggest that yeast glycerol-P and DHAP acyltransferase activities represent dual catalytic functions of a single membrane-bound enzyme. Furthermore, since no acyl-DHAP oxidoreductase activity could be detected in yeast membranes, the DHAP pathway for glycerolipid synthesis may not operate in yeast.

Acyl Coenzyme A↗
PubMed1979

Reduction of human blood O2 affinity using dihydroxyacetone, phosphate, and pyruvate.

Human blood oxygen affinity (BOA) was measured after blood from six normal donors was incubated with 4 concentrations of dihydroxyacetone (0.022, 0.044, 0.088, and 0.175 M) plus equimolar disodium phosphate and pyruvate (sodium salt) (0.013, 0.025, 0.05 and 0.1 M) in solutions labeled DDP X 1, DDP X 2, DDP X 4, and DDP X 8, respectively. Blood P50 rose (BOA was reduced) from a control value of 26.0 +/- 0.4 Torr (mean +/- SD) to 29.4 +/- 0.6, 30.6 +/- 0.4, 31.9 +/- 0.15 and 33.3 +/- 1.4 Torr after 2 h of incubation at 37 degrees C with solutions DDP X 1, DDP X 2, DDP X 4, and DDP X 8, respectively. P50 changes at 2 h were 75% complete within 30 min. During these incubations, erythrocyte 2,3-diphosphoglycerate (2,3-DPG) concentration rose from 0.76 +/- 0.09 mol/mol Hb (control) to 1.09 +/- 0.17, 1.14 +/- 0.10, 1.33 +/- 0.15, and 1.45 +/- 0.25 mol/mol Hb with increasing solution concentration. BOA is decreased by an increase in erythrocyte 2,3-DPG. Reduced BOA may improve oxygen delivery to ischemic tissues.

Animals↗
PubMed1990

Enhancement of arm exercise endurance capacity with dihydroxyacetone and pyruvate.

The effects of dietary supplementation of dihydroxyacetone and pyruvate (DHAP) on endurance capacity and metabolic responses during arm exercise were determined in 10 untrained males (20-26 yr). Subjects performed arm ergometer exercise (60% peak O2 consumption) to exhaustion after consumption of standard diets (55% carbohydrate, 15% protein, 30% fat; 35 kcal/kg) containing either 100 g of Polycose (placebo, P) or DHAP (3:1, treatment) substituted for a portion of carbohydrate. The two diets were administered in a random order, and each was consumed for a 7-day period. Biopsy of the triceps muscle was obtained immediately before and after exercise. Blood samples were drawn through radial artery and axillary vein catheters at rest, after 60 min of exercise, and at exercise termination. Arm endurance was 133 +/- 20 min after P and 160 +/- 22 min after DHAP (P less than 0.01). Triceps glycogen at rest was 88 +/- 8 (P) and 130 +/- 19 mmol/kg (DHAP) (P less than 0.05). Whole arm arteriovenous glucose difference (mmol/l) was greater (P less than 0.05) for DHAP than P at rest (0.60 +/- 0.12 vs. 0.05 +/- 0.09) and after 60 min of exercise (1.00 +/- 0.12 vs. 0.36 +/- 0.11), but it did not differ at exhaustion. Neither respiratory exchange ratio nor respiratory quotient differed between trials at rest, after 60 min of exercise, or at exhaustion. Plasma free fatty acid, glycerol, beta-hydroxybutyrate, catecholamines, and insulin were similar during rest and exercise for both diets. Feeding DHAP for 7 days increased arm muscle glucose extraction before and during exercise, thereby enhancing submaximal arm endurance capacity.

Adult↗
PubMed2001

Dihydroxyacetone in a new formulation--a powerful therapeutic option in vitiligo.

BACKGROUND: Most treatment protocols for vitiligo require a long treatment duration and usually do not result in complete repigmentation. Therefore, cosmetically acceptable and easily to handle alternatives are warranted. OBJECTIVE: To evaluate the properties of dihydroxyacetone (DHA) in a new formulation for the treatment of vitiligo on exposed areas. METHODS: We treated 10 patients suffering from vitiligo affecting the face and/or hands with a newly introduced, commercially available self-bronzing cream containing DHA 5%. DHA was applied every second day. RESULTS: The characteristic pigmentation showed very satisfactory cosmetic results in 8 out of 10 patients after 2 weeks of treatment. CONCLUSION: The new DHA formulation is a practical and well-accepted treatment modality.

Cosmetics↗
PubMed1993

Dihydroxyacetone test as a substitute for the dansyl chloride test.

The hazards of the dansyl chloride test are not negligible. We introduce the dihydroxyacetone test as a safe substitute. Several advantages are highlighted including easy and reproducible measurements of the modifications in skin color by chromometry in the L* a* b* (luminance, hue, chroma) mode. The color variations in time as well as the fade-out of DHA-induced pigmentation by some cleansing skin care products are revealed 'in vivo' as well as 'ex vivo' on D-Squame collections of stratum corneum.

Adult↗
PubMed1987

Protection of photosensitized rats against long ultraviolet radiation by topical application of compounds with structures similar to that of dihydroxyacetone.

Dihydroxyacetone (DHA), a browning agent, protects photosensitive rats and humans against long ultraviolet radiation (UVA, 320-400 nm) and visible (blue) light. The photoprotective efficacy of DHA and structurally similar compounds was assessed as prevention of edema in the paws of psoralen-sensitized rats, after exposure to blacklight fluorescent lamps. Methylglyoxal produced a yellow-brown color and provided nearly the same protection as DHA, whereas monohydroxyacetone did not color the skin and afforded little or no protection. Glyceraldehyde provided a moderate amount of protection, which was enhanced by prior exposure of the agent to alkaline pH. A solution of 5-hydroxymethylfurfuraldehyde was yellow and provided minimal protection by staining the skin rather than browning it. We conclude that the ability to produce a brown color in skin is a useful criterion for screening compounds for photoprotective efficacy against UVA radiation.

Aldehydes↗
PubMed1975

Protection against long ultraviolet and/or visible light with topical dihydroxyacetone. Implications for the mechanism of action of the sunscreen combination, dihydroxyacetone/naphthoquinone.

Dihydroxyacetone (DHA) chemically induces long ultraviolet (UV) and/or visible photoprotection into the stratum corneum as demonstrated by (a) long UV protection of albino rats which were psoralen-photosensitized to black fluorescent light and (b) sunlight protection of five patients with long UV and/or visible photosensitivity. Previously, DHA treatment of skin was considered to provide no protection against UV. For clinical use, the combination of DHA and lawsone (2-hydroxy-1,4-naphthoquinone) is preferred to DHA alone, because it provides rapid, positive protection over a range extending from short UV into the visible region of sunlight.

Administration, Topical↗
PubMed2006

Facile syntheses of acyl dihydroxyacetone phosphates and lysophosphatidic acids having different acyl groups.

In this study, we report novel and simple chemical syntheses of acyl dihydroxyacetone phosphate (DHAP) and 1-acyl glycero-3-phosphate [lysophosphatidic acid (LPA)], key intermediaries in the formation of glycerolipids containing ester and ether bonds. The synthesis of acyl DHAPs involved acylating the dimethyl ketal of DHAP by acid anhydride using 4-pyrrolidinopyridine as the catalyst, and the resulting product was deketalized by HClO(4) in acetone to produce acyl DHAP. The acid anhydride was either added directly or generated in the reaction mixture from the corresponding fatty acid using dicyclohexylcarbodiimide as the condensing agent. Using these methods, a number of acyl DHAPs having short-, medium-, and long-chain saturated and unsaturated acyl groups were synthesized, with overall yields from 37% to 75%. The activities of these acyl DHAPs as substrates for guinea pig liver peroxisomal acyl DHAP:NADPH reductase and alkyl DHAP synthase were then determined. Next, starting from these acyl DHAPs, a variety of LPAs were synthesized by chemical reduction of the ketone group. Biological activities of these LPAs were determined by measuring their relative abilities to release intracellular Ca(2+) via the LPA receptor. A combined chemical-enzymatic method is also described to prepare the natural LPA from the racemic mixture.

Calcium↗
PubMed2005

Nonenzymatic reaction of dihydroxyacetone with hydrogen peroxide enhanced via a Fenton reaction.

An analysis of the reaction of dihydroxyacetone with hydrogen peroxide was performed using HPLC with electrochemical and spectrophotometric detection and EPR spectroscopy of the reactants and products. Glycolate production in such a reaction has been documented, and the glycolate yield analyzed at different pH values. The participation of hydroxyl free radical is shown with DEPMPO spin trap. Two types of mechanisms are proposed, one at higher pH values and pronounced participation of free radicals (enhanced by the presence of metal ions and Fenton reaction) and the other at lower pH values, with decreased free radical production and lower glycolate yield.

Cations↗