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PubMed1977

Tumor regression after intralesional injection of emulsified trehalose-6,6'-dimycolate (cord factor): efficacy increases with oil concentration.

Injection of emulsified trehalose-6,6'-dimycolate (TDM), a mycobacterial glycolipid, into transplants of an established, syngeneic murine fibrosarcoma induced complete regression of tumor in a number of animals. The number of animals in wich tumor regressed completely depended on the amount of oil in the emulsion. The anti-tumor activity of the TDM emulsion containing the highest concentration of oil was equivalent to that of living BCG.

Animals↗
PubMed2006

Impact of freeze-drying on ionization of sulfonephthalein probe molecules in trehalose-citrate systems.

"pH memory," i.e., correlation between pH of solution before freeze-drying and chemical reactivity in the freeze-dried state, has been reported in many systems. In this study, the "pH memory" is explored by comparing the extent of protonation of sulfonephthalein probe molecules, bromophenol blue, bromocresol green, and chlorophenol red, in aqueous solution in the pH range of 3.4-6.0 and in the resulting freeze-dried amorphous matrix (lyophile) containing trehalose and sodium citrate buffer. The protonation of the probe molecules was measured in the lyophiles by diffuse reflectance visible spectroscopy, and compared with that in the solution before drying. The protonation of the indicators in the amorphous matrix correlated with solution pH, that is, an increase in solution pH resulted in a progressive decrease in the indicator protonation in the corresponding lyophile. However, the protonation was consistently higher in the lyophile than in the corresponding solution. The Hammett acidity function of lyophiles was calculated based on the extent of protonation of the probe molecules. Protonation of the probe molecules and the Hammett acidity function depended not only on prelyophilization solution pH, but also on the residual water content and the presence of amorphous sugar in the lyophile.

Bromcresol Green↗
PubMed2006

Disruption of insulin pathways alters trehalose level and abolishes sexual dimorphism in locomotor activity in Drosophila.

Insulin signaling pathways are implicated in several physiological processes in invertebrates, including the control of growth and life span; the latter of these has also been correlated with juvenile hormone (JH) deficiency. In turn, JH levels have been correlated with sex-specific differences in locomotor activity. Here, the involvement of the insulin signaling pathway in sex-specific differences in locomotor activity was investigated in Drosophila. Ablation of insulin-producing neurons in the adult pars-intercerebralis was found to increase trehalosemia and to abolish sexual dimorphism relevant to locomotion. Conversely, hyper-insulinemia induced by insulin injection or by over-expression of an insulin-like peptide decreases trehalosemia but does not affect locomotive behavior. Moreover, we also show that in the head of adult flies, the insulin receptor (InR) is expressed only in the fat body surrounding the brain. While both male and female InR mutants are hyper-trehalosemic, they exhibit similar patterns of locomotor activity. Our results indicate that first, insulin controls trehalosemia in adults, and second, like JH, it controls sex-specific differences in the locomotor activity of adult Drosophila in a manner independent of its effect on trehalose metabolism.

Animals↗
PubMed2004

The trehalose pathway and intracellular glucose phosphates as modulators of potassium transport and general cation homeostasis in yeast.

Trk, encoded by the partially redundant genes TRK1 and TRK2, is the major potassium transporter of Saccharomyces cerevisiae. This system is specific for potassium and rubidium but, by reducing the electrical membrane potential of the plasma membrane, Trk decreases the uptake of toxic cations such as lithium, calcium, aminoglycosides and polyamines, which are transported by other systems. Gain- and loss-of-function studies indicate that TPS1, a gene encoding trehalose-6-phosphate synthase and known to modulate glucose metabolism, activates Trk and reduces the sensitivity of yeast cells to many toxic cations. This effect is independent of known regulators of Trk, such as the Hal4 and Hal5 protein kinases and the protein phosphatase calcineurin. Mutants defective in isoform 2 of phosphoglucomutase (pgm2) and mutants defective in isoform 2 of hexokinase (hxk2) exhibit similar phenotypes of reduced Trk activity and increased sensitivity to toxic cations compared with tps1 mutants. In all cases Trk activity was positively correlated with levels of glucose phosphates (glc-1-P and glc-6-P). These results indicate that Tps1, like Pgm2 and Hxk2, increases the levels of glucose phosphates and suggest that these metabolites, directly or indirectly, activate Trk.

Adenosine Triphosphatases↗
PubMed1995

Pentose cycling and the distribution of 13C in trehalose during glucogenesis from 13C-labelled substrates in an insect.

Redistribution of 13C in trehalose (Tre) due to pentose cycling was observed in vivo in Manduca sexta during glucogenesis from [3-13C]alanine (Ala) and [2-13C]glycerol (Gly). The extent of cycling was affected by dietary composition. Larvae maintained on a low-carbohydrate diet (LCD) exhibited approximately 13% cycling, while those on a complete-balanced diet (CBD) or low-fat diet (LFD) displayed much higher rates of cycling. Significant incorporation of 13C via reversal of the non-oxidative phase was evident on all diets but was greatest on the CBD and LFD. In contrast to conclusions from previous studies with insects, the present results indicate that under normal conditions the pentose pathway is not the principal source of triose phosphates for oxidative catabolism during larval development.

Animals↗
PubMed1997

In vitro study of the protective effect of trehalose and dextran during freezing of human red blood cells in liquid nitrogen.

Two nonpermeant cryoprotectants, the disaccharide trehalose and the polymeric carbohydrate (dextran, 40 kDa), were assessed as substitutes for glycerol in the cryopreservation of human red blood cells (RBC). The agents were evaluated by measuring the percentage of RBC recovery (total of free hemoglobin after freezing) and by evaluating the erythrocyte state after freezing. Ninety percent of the red cells were recovered after freezing in 30% (w/v) dextran in liquid nitrogen, which is very close to the recovery obtained in 35. 5% (w/v) glycerol (92%). The activities of pyruvate kinase and glucose-6-phosphate dehydrogenase of RBCs frozen and thawed with dextran were not modified, and the 2,3-diphosphoglycerate was reduced by 26%, but remained within normal values. ATP was reduced by 56%. The erythrocyte membrane integrity, evaluated by its osmotic fragility, was not altered, and the RBCs protected by dextran retained their normal discoid shape without the formation of microvesicles. The 24-h hemolysis of the washed red cells after storage at 4 degrees C was 7%. These results suggest that dextran protects red blood cells during freezing in liquid nitrogen, but that some effort is still needed to limit the drop of ATP concentration. One of the main advantages of dextran is that it does not penetrate the RBCs and requires less washing than glycerol.

Adenosine Triphosphate↗
PubMed1996

Evaluation of a new solution containing trehalose for twenty-hour canine lung preservation.

We examined the efficacy of two new preservation solutions containing trehalose--an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution--in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n = 5 for each solution) after pretreatment with PGE1 (20 micrograms/kg) and were stored for 20 h at 4 degrees C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.

Analysis of Variance↗
PubMed1987

Osmoregulation in Escherichia coli by accumulation of organic osmolytes: betaines, glutamic acid, and trehalose.

It has been shown previously that externally added glycine betaine is accumulated in Escherichia coli in response to the external osmotic strength. Here we have shown, by using nuclear magnetic resonance spectroscopy and radiochemical methods, that E. coli growing in a glucose-mineral medium of elevated osmotic strength generated with NaCl, had the same capacity to accumulate proline betaine and glycine betaine. Its capacity to accumulate gamma-butyrobetaine was, however, 40 to 50% lower. Accordingly, externally added proline betaine and glycine betaine stimulated aerobic growth of osmotically stressed cells equally well, and they were more osmoprotective than gamma-butyrobetaine. In cells grown at an osmotic strength of 0.64, 1.01, or 1.47 osmolal, respectively, the molal cytoplasmic concentration of the two former betaines corresponded to 29, 38, or 58% of the external osmotic strength. Nuclear magnetic resonance spectroscopy revealed that trehalose and glutamic acid were the only species of organic osmolytes accumulated in significant amounts in cells grown under osmotic stress in glucose-mineral medium without betaines. Their combined molal concentration in the cytoplasm of cells grown at 1.01 osmolal corresponded to 27% of the external osmotic strength.

Amino Acids↗
PubMedDate not supplied

Succinoyl trehalose lipid induced differentiation of human monocytoid leukemic cell line U937 into monocyte-macrophages.

A novel type of succinoyl trehalose lipid (STL-1) prepared from n-hexadecane-culture of Rhodococcus erythropolis SD-74 markedly inhibited the growth of a human monocytoid leukemic cell line, U937, and induced its morphological alteration along a monocyte-macrophage lineage. STL-1 markedly increased differention-associated characteristics in macrophage, such as nitroblue tetrazolium reducing ability, appearance of Fc receptor, phagocytic activities in U937. Furthermore, U937 cells, which were activated with STL-1 exhibited cytotoxic activity against human lung carcinoma cell line A549. However, STL-1 did not affect growth of a normal human fetal lung cell line TIG-1. The individual components of STL-1, neither sugar moiety nor fatty acids in the free form, were effective at inducing the differentiation of U937 cell. From these results, we concluded that STL-1 has low cytotoxicity against normal human cells and the ester molecule itself is responsible for the activity of inducing differentiation of human monocytoid leukemic cell line U937 into monocyte-macrophage which results in the stimulation of the production of some cytotoxic substances.

Biomarkers↗
PubMed1986

Incorporation of 3-deoxy-3-fluoro-D-glucose into glycogen and trehalose in fat body and flight muscle in Locusta migratoria.

Flight muscle and fat body extracts from Locusta migratoria were incubated with D-[U-14C]-glucose or D-[3-3H]-3-deoxy-3-fluoroglucose and the products were analyzed. In the case of the latter compound, radio-chromatographic analysis yielded glycogen and trehalose fractions that were shown by 19F nuclear magnetic resonance to contain fluorine. Acid hydrolysis of these fractions liberated tritium labelled 3-deoxy-3-fluoro-D-glucose. In addition to the formation of "fluoroglycogen" and "fluorotrehalose" in these tissue extracts, there was an accumulation of tritium labelled fructose.

Adipose Tissue↗
PubMed2002

The GCR1 gene function is essential for glycogen and trehalose metabolism in Saccharomyces cerevisiae.

Trehalose (Tre) and glycogen (Glg) are synthesized in response to unfavorable growth conditions from glycolytic intermediates in Saccharomyces cerevisiae. Transcription of the glycolytic genes is activated by the Gcr1p complex, the DNA binding transcription factor that directly associates with the CT-box sequences on the promoter region of the glycolytic genes. gcr1 mutant yeast cells cannot utilize glucose effectively. Glg and Tre levels in stationary-phase gcr1 mutant yeast cells were 20-50% of those in the wild-type strain. Likewise, stress-induced accumulation of Tre and Glg in gcr1 mutant cells was significantly lower than in the wild type. In addition, both the synthesis and the degradation of Tre and Glg are very slow in the gcr1 mutant. It seems that Gcr1p function is essential for the coordinated regulation of glycolysis, Tre and Glg metabolism in S. cerevisiae.

DNA-Binding Proteins↗
PubMed2003

Synthesis of a new vanadyl(IV) complex with trehalose (TreVO): insulin-mimetic activities in osteoblast-like cells in culture.

Vanadium compounds show interesting biological and pharmacological properties. Some of them display insulin-mimetic effects and others produce anti-tumor actions. The bioactivity of vanadium is present in inorganic species like the vanadyl(IV) cation or vanadate(V) anion. Nevertheless, the development of new vanadium derivatives with organic ligands which improve the beneficial actions and decrease the toxic effects is of great interest. On the other hand, the mechanisms involved in vanadium bioactivity are still poorly understood. A new vanadium complex of the vanadyl(IV) cation with the disaccharide trehalose (TreVO), Na(6)[VO(Tre)(2)].4H(2)O, here reported, shows interesting insulin-mimetic properties in two osteoblast cell lines, a normal one (MC3T3E1) and a tumoral one (UMR106). The complex affected the proliferation of both cell lines in a different manner. On tumoral cells, TreVO caused a weak stimulation of growth at 5 microM but it inhibited cell proliferation in a dose-response manner between 50 and 100 microM. TreVO significantly inhibited UMR106 differentiation (15-25% of basal) in the range 5-100 microM. On normal osteoblasts, TreVO behaved as a mitogen at 5-25 microM. Different inhibitors of the MAPK pathway blocked this effect. At higher concentrations (75-100 microM), the complex was a weak inhibitor of the MC3T3E1 proliferation. Besides, TreVO enhanced glucose consumption by a mechanism independent of the PI3-kinase activation. In both cell lines, TreVO stimulated the ERK phosphorylation in a dose- and time-dependent manner. Different inhibitors (PD98059, wortmannin, vitamins C and E) partially decreased this effect, which was totally inhibited by their combination. These results suggest that TreVO could be a potential candidate for therapeutic treatments.

3T3 Cells↗
PubMed1999

Fatty acid delta9-desaturation in the Triatoma infestans fat body: response to food and trehalose administrations.

The effects of food intake and carbohydrate administration on fatty acid delta9-desaturation were investigated in isolated microsomes from Triatoma infestans fat body. Fifth instar nymphs, which were solely blood-fed just after the molt and then fasted, were used as controls and for determination of optimal assay conditions. Both [1-14C]palmitic and [1-14C]stearic acids in a medium containing ATP, CoA, MgCl2, NADH, NaF, and O2 were tested. For the control group, optimal conditions were a pH of 6.8-7.2, an incubation temperature of 29 degrees C, and an incubation time of 10 min. delta9-Desaturation depended on the presence of reduced pyridine dinucleotides; NADH and NADPH were equally efficient. Stearic acid showed a higher apparent Vmax than palmitic acid, but the apparent Km were very similar. When fifth instar nymphs were blood-fed weekly, a marked increase of delta9-desaturation was observed for both acids. Higher desaturation activity was also induced by injection of the carbohydrate trehalose into the hemolymph of fasted nymphs. These results indicate that insect delta9-desaturation, like the mammalian counterpart, is sensitive to dietary changes and carbohydrate administration.

Animals↗
PubMed1996

Trehalose-containing solutions enhance preservation of cultured endothelial cells.

BACKGROUND AND METHODS: We have developed two types of preservation solutions containing trehalose. ET-Kyoto solution (ET-K) is an extracellular type and IT-Kyoto solution (IT-K) is an intracellular type. In the present study we examined with in vitro assays the ability of ET-K, IT-K, Euro-Collins (EC), and University of Wisconsin (UW) solutions to preserve a murine endothelial cell line. The viability of cells stored in the solutions at 4 degrees C was determined by trypan blue exclusion and MTT assay. RESULTS: Trypan blue exclusion showed the viability after 48 hours of cold storage to be 49.5 +/- 4.7% (mean +/- standard error) in ET-K, 59.5 +/- 0.7% in IT-K, 29.2 +/- 2.5% in EC, and 55.3 +/- 7.6% in UW (ET-K or UW versus EC, p < 0.05; IT-K versus EC, p < 0.01). MTT assay absorbance values for cells after 48 hours of cold storage were 0.366 +/- 0.0066 (mean +/- standard error) in ET-K, 0.358 +/- 0.0044 in IT-K, 0.336 +/- 0.011 in EC, and 0.362 +/- 0.0019 in UW (ET-K or UW versus EC, p < 0.05). After 120 hours, absorbance values for cells were 0.303 +/- 0.0038 in ET-K, 0.269 +/- 0.0034 in IT-K, 0.186 +/- 0.011 in EC, and 0.265 +/- 0.0066 in UW (ET-K versus UW, p < 0.05; ET-K versus IT-K, p < 0.01; ET-K, IT-K or UW versus EC, p < 0.01). CONCLUSIONS: As far as the ability to preserve a murine endothelial cell line at a low temperature was concerned, the ET-K solution was superior to the UW solution, the IT-K solution and UW solution were equal, and the ET-K and IT-K solutions were superior to the EC solution.

Animals↗
PubMed1985

The crystal structure of anhydrous alpha,alpha-trehalose at -150 degrees.

The crystal structure of alpha,alpha-trehalose (alpha-D-glucopyranosyl alpha-D-glucopyranoside), C12H22O11, is monoclinic, P2(1), Z = 2, with unit cell dimensions at -150 degrees [20 degrees] of a = 12.971(5) [13.003(5)], b = 8.229(4) [8.252(4)], c = 6.789(3) [6.799(3)] A, beta = 98.12(4) [98.33(4)]. The crystal structure was solved by using MULTAN, and refined to R = 0.059, Rw = 0.048 for 1564 intensities, measured with MoK alpha radiation. The molecular structure is very similar to that observed in the dihydrate crystals. It has approximate C2 symmetry. Both glucopyranosyl groups are in the 4C1 conformation. The linkage torsion angles, O-5-C-1-O-1-C-1, are +60.8 degrees and +60.1 degrees. The primary alcohol groups are oriented gauche/gauche and gauche/trans, as in the dihydrate structure. A comparison of the cross-polarization, magic-angle-spinning (c.p.-m.a.s.), 13C-n.m.r. spectra for powders of the crystalline anhydrous and dihydrate forms shows differences in resonances assigned to C-1 and C-4 that would not be anticipated from the results of the crystal-structure analyses.

Crystallization↗
PubMed1986

Two syntheses of 3-amino-3-deoxy-alpha-D-altropyranosyl 3-amino-3-deoxy-alpha-D-altropyranoside, a new analog of alpha,alpha-trehalose, involving reduction of a diazide and reductive amination of a diketone.

A new diamino sugar, 3-amino-3-deoxy-alpha-D-altropyranosyl 3-amino-3-deoxy-alpha-D-altropyranoside (5) was synthesized by two routes starting from alpha,alpha-trehalose. The first route involved reduction and deprotection of a previously described, benzylidenated diazido analog. The second approach proceeded from the known 2,2'-di-O-benzyl-4,6;4',6'-bis-O-benzylidene derivative of alpha-D-altropyranosyl alpha-D-altropyranoside, to the corresponding 3,3'-diketone, which was subjected to reductive amination with sodium cyanoborohydride and ammonium acetate. The major product, separated in 39% yield from by-products after N-acetylation, was deprotected to give 5. Four by-products were isolated in low yields and determined to be monoaminated analogs which comprise two epimeric, 3'-hydroxy structures and two 3'-epimeric, 3'-cyano-3'-hydroxy structures in their non-aminated residues. A number of observations concerning the 13C- and 1H-n.m.r. spectra of the products are discussed, especially with regard to chemical-shift dependencies for certain ring and substituent protons, and attention is drawn to some inter-residue shielding phenomena.

Amination↗
PubMed1987

Glycosylated trehalose. Synthesis of the oligosaccharides of the glycolipid-type antigens from Mycobacterium smegmatis.

The oligosaccharide components, 3-O-Me-beta-D-Glcp-(1----3)-beta-D-Glcp-(1----4)-beta-D-Glcp-(1----6)- alpha-D-Glcp-(1----1)-alpha-D-Glcp (1) and beta-D-Glcp-(1----4)-beta-D-Glcp-(1----6)-alpha-D-Glcp-(1----1)-alpha-D- Glcp, of the glycolipid-type antigens isolated from M. smegmatis have been synthesised from 2,3,4,2',3',4',6'-hepta-O-acetyl-alpha,alpha-trehalose and the appropriate glycosyl bromides under Helferich conditions with Hg(CN)2 as the promoter. Condensation of the trisaccharide glycosyl bromide 27 gave an orthoester derivative (28) which could be rearranged, using HgBr2 or boron trifluoride etherate, into the acetylated derivative (29) of 1. The model compound beta-D-Glcp-(1----6)-alpha-D-Glcp-(1----1)-alpha-D-Glcp has also been synthesised.

Antigens, Bacterial↗