Measurement of the Hemoglobin Concentration in Deoxyhemoglobin S Polymers and Characterization of the Polymer Water Compartment

Bookchin, Robert M.; Balazs, Tania; Lew, Virgilio L.

doi:10.1006/jmbi.1994.1707

Cited by 11 publications

(11 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cell water volume estimated from MCHC and vali- dated by urea C i -to-C o ϭ 1.0, is consistent with the long-standing observation that virtually all water in RBCs was available for solvation of small molecules (28,29). More recently, Bookchin et al (22) showed that even the water contained in the highly structured dense protein domain of intracellular polymerized hemoglobin S was accessible to small molecules, including glucose. Furthermore, the C i -to-C o gradient did not depend on high intracellular hemoglobin concentrations.…”

Section: Discussionsupporting

confidence: 79%

See 1 more Smart Citation

Evidence for Interindividual Heterogeneity in the Glucose Gradient Across the Human Red Blood Cell Membrane and Its Relationship to Hemoglobin Glycation

et al. 2008

View full text Add to dashboard Cite

OBJECTIVE-To determine whether interindividual heterogeneity in the erythrocyte (red blood cell [RBC]) transmembrane glucose gradient might explain discordances between A1C and glycemic control based on measured fructosamine. RESEARCH DESIGN AND METHODS-We modeled the relationship between plasma glucose and RBC glucose as the concentration distribution (C i -to-C o ratio) of a nonmetabolizable glucose analog 14 C-3-O-methyl glucose ( 14 C-3OMG) inside (C i ) and outside (C o ) RBCs in vitro. We examined the relationship between that distribution and the degree of glycation of hemoglobin in comparison with glycation of serum proteins (fructosamine), the glycation gap. A1C, fructosamine, and in vitro determination of the 14 C-3OMG distribution in glucose-depleted RBCs were measured in 26 fasted subjects.RESULTS-The C i -to-C o ratio 0.89 Ϯ 0.07 for 3-O-methyl-Dglucopyranose (3OMG) ranged widely (0.72-1.04, n ϭ 26). In contrast, urea C i -to-C o (1.015 Ϯ 0.022 [range 0.98 -1.07], P Ͻ 0.0001) did not. Concerning mechanism, in a representative subset of subjects, the C i -to-C o ratio was retained in RBC ghosts, was not dependent on ATP or external cations, and was reestablished after reversal of the glucose gradient. The 3OMG C i -to-C o ratio was not correlated with serum fructosamine, suggesting that it was independent of mean plasma glucose. However, C i -to-C o did correlate with A1C (R 2 ϭ 0.19) and with the glycation gap (R 2 ϭ 0.20), consistent with a model in which differences in internal glucose concentration at a given mean plasma glucose contribute to differences in A1C for given level of glycemic control.CONCLUSIONS-The data demonstrate interindividual heterogeneity in glucose gradients across RBC membranes that may affect hemoglobin glycation and have implications for diabetes complications risk and risk assessment. Diabetes 57: [2445][2446][2447][2448][2449][2450][2451][2452] 2008 A 1C is the current gold standard for determination of chronic glycemic control in people with diabetes. Yet it is common to find hematologically normal people with diabetes in whom A1C appears discordant from other measures of glycemic control. Some have suggested the notion of a "hemoglobin glycation index" to assess A1C discordance from mean blood glucose (1-3). We have quantitated this discordance with the use of the glycation gap (GG), a measure of the disparity between two integrated measures of glycemic control, one intracellular in red blood cells (RBCs), A1C, and the other extracellular, glycated serum protein (GSP) measured as fructosamine (4). A non-zero GG could result from differences between the ambient glucose concentrations or rates of glycation in the intracellular and extracellular compartments, and/or interindividual differences in the turnover/metabolism of underlying proteins. We have demonstrated that the GG is reproducible within subjects over time and is associated with important clinical end points. In longstanding type 1 diabetes, there is a over a twofold rise in prevalence of nephropathy in pati...

show abstract

Section: Discussionsupporting

confidence: 79%

“…molecules such as urea. Bookchin et al found similar results for glucose (22). Thus, C i -to-C o ratios Ͻ1 are not due to variations or error in estimation of water content of the cells.…”

Section: Resultsmentioning

confidence: 65%

Evidence for Interindividual Heterogeneity in the Glucose Gradient Across the Human Red Blood Cell Membrane and Its Relationship to Hemoglobin Glycation

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Determination of C sat -Polymer solubilities of the hemoglobins under study were determined by the "Dextran-C sat " micromethod of Bookchin et al (20), with minor modifications. This method is based on the marked decrease in the solubility of deoxy-HbS on admixture with 70-kDa dextran, at physiological ionic strength and pH (a preliminary account of this method and results is described in Ref.…”

Section: Methodsmentioning

confidence: 99%

“…This method is based on the marked decrease in the solubility of deoxy-HbS on admixture with 70-kDa dextran, at physiological ionic strength and pH (a preliminary account of this method and results is described in Ref. 20; full report in preparation). A comparison of the results found with this procedure with those reported previously using another method is described below.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

A Recombinant Sickle Hemoglobin Triple Mutant with Independent Inhibitory Effects on Polymerization

Himanen

Mirza

Chait

et al. 1996

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

As part of a comprehensive effort to map the most important regions of sickle hemoglobin that are involved in polymerization, we have determined whether two sites previously shown to be involved, Leu-88(␤) and Lys-95(␤), had additive effects when substituted. The former site is part of the hydrophobic pocket that binds Val-6(␤), the natural mutation of HbS, and the latter site is a prominent part of the hemoglobin exterior. A sickle hemoglobin triple mutant with three amino acid substitutions on the ␤-chain, E6V/L88A/K95I, has been expressed in yeast and characterized extensively. Its oxygen binding curve, cooperativity, response to allosteric effectors, and the alkaline Bohr effect showed that it was completely functional. The polymer solubility of the deoxy triple mutant, measured by a new micromethod requiring reduced amounts of hemoglobin, was identical to that of the E6V(␤)/K95I(␤) mutant, i.e. when the K95I(␤) substitution was present on the same tetramer together with the naturally occurring E6V(␤) substitution, the L88A(␤) replacement had no additive effect on polymer inhibition. The results suggest that Lys-95(␤) on the surface of the tetramer and its complementary binding region on the adjoining tetramer are potential targets for the design of an effective antisickling agent.

show abstract

Inhibition of Sickle Hemoglobin Polymerization as a Basis for Therapeutic Approaches to Sickle‐Cell Anemia

Noguchi

Schechter

Haley³

et al. 2003

Burger's Medicinal Chemistry and Drug Discovery

View full text Add to dashboard Cite

This chapter reviews current understanding of the molecular and cellular basis of the pathophysiology of sickle‐cell anemia, with emphasis on the biophysics of the intracellular polymerization of sickle hemogobin. Factors that modify the severity of the disease manifestations, primarily by altering polymerization tendency, are discussed. This framework is used to present an overview of the major rational approaches to the therapy of sickle‐cell anemia based on inhibiting polymerization with agents that affect either the hemoglobin molecule or the sickle erythrocyte. Discussion of agents that may decrease vascular entrapment of sickle erythrocytes is also presented. Detailed review of the most important current approaches to therapy—pharmacologically elevating fetal hemoglobin—focuses primarily on hydroxyurea, the only drug currently FDA approved for treating sickle‐cell anemia. A brief discussion of other approaches, including stem cell transplantation and gene therapy, concludes the chapter.

show abstract

Measurement of the Hemoglobin Concentration in Deoxyhemoglobin S Polymers and Characterization of the Polymer Water Compartment

Cited by 11 publications

References 0 publications

Evidence for Interindividual Heterogeneity in the Glucose Gradient Across the Human Red Blood Cell Membrane and Its Relationship to Hemoglobin Glycation

Evidence for Interindividual Heterogeneity in the Glucose Gradient Across the Human Red Blood Cell Membrane and Its Relationship to Hemoglobin Glycation

A Recombinant Sickle Hemoglobin Triple Mutant with Independent Inhibitory Effects on Polymerization

Inhibition of Sickle Hemoglobin Polymerization as a Basis for Therapeutic Approaches to Sickle‐Cell Anemia

Contact Info

Product

Resources

About