A Modified Carbon Monoxide Breath Test for Measuring Erythrocyte Lifespan in Small Animals

Abstract

This study was to develop a CO breath test for RBC lifespan estimation of small animals. The ribavirin induced hemolysis rabbit models were placed individually in a closed rebreath cage and air samples were collected for measurement of CO concentration. RBC lifespan was calculated from accumulated CO, blood volume, and hemoglobin concentration data. RBC lifespan was determined in the same animals with the standard biotin-labeling method. RBC lifespan data obtained by the CO breath test method for control (CON, 49.0 ± 5.9 d) rabbits, rabbits given 10 mg/kg·d−1 of ribavirin (RIB10, 31.0 ± 4.0 d), and rabbits given 20 mg/kg·d−1 of ribavirin (RIB20, 25.0 ± 2.9 d) were statistically similar (all p > 0.05) to and linearly correlated (r = 0.96, p < 0.01) with the RBC lifespan data obtained for the same rabbits by the standard biotin-labeling method (CON, 51.0 ± 2.7 d; RIB10, 33.0 ± 1.3 d; and RIB20, 27.0 ± 0.8 d). The CO breath test method takes less than 3 h to complete, whereas the standard method requires at least several weeks. In conclusion, the CO breath test method provides a simple and rapid means of estimating RBC lifespan and is feasible for use with small animal models.

Rapid CO breath test screening of drugs for protective effects on ribavirin-induced hemolysis in a rabbit model: a pilot study

“…Our method measures expired endogenous CO that has been allowed to accumulate in a sealed box, removing the need for continuous monitoring of blood COHb concentrations [19]. We have demonstrated previously that RBC lifespan data calculated based on accumulated CO concentration measured with our rebreath system, blood volume determined by the EBD dilution technique, and hemoglobin concentration were virtually identical to RBC lifespan data obtained by the biotin labeling method [7]. The present study provides further demonstration of the reliability of this method.…”

“…In practice, operation of the rebreath apparatus is very simple and the data are measured in an automated fashion. Furthermore, the rebreath system enables RBC lifespan to be determined within a few hours rather than in several weeks as is needed with the currently available RBC labeling approaches [7].…”

“…However, classical techniques for measuring RBC lifespan, such as 51 Cr or biotin labeling protocols, are complex and time-consuming. We have developed a simple, rapid test that utilizes breath carbon monoxide (CO) concentration to quantitfy RBC survival in rabbits [7]. The present study is a proof of principle pilot study in which we examine the utility of using our small-animal CO breath test procedure for screening of drugs with potential efficacy for countering ribavirin-induced anemia in rabbits.…”

Iron mobilization during lactation reduces oxygen stores in a diving mammal

“…Erythrocyte and hemoprotein turnover rates have yet to be measured in marine mammals. However, pinnipeds have exceptionally high carboxyhemoglobin and heme oxygenase relative to terrestrial mammals 72,73 , which indicate a greater magnitude of hemolysis and rapid erythrocyte turnover 74,75 . Turnover rates would also influence the time it takes for hemoprotein levels to recover post-weaning.…”

Red Blood Cell Lifespan < 74 Days Can Clinically Reduce Hb1Ac Levels in Type 2 Diabetes

“…However, there is still a lack of evidence about how and to what degree the RBC lifespan affects the HbA1c value in the T2DM population. In this study, a CO breath test, which is a reliable method for quickly determining the human RBC lifespan for clinical applications [ 13 , 14 , 15 , 16 ], was used to measure the RBC lifespan of patients with T2DM, and the relationship between the HbA1c test value and the average blood glucose level of patients with T2DM in different RBC lifespan groups was analyzed to provide useful guidance for accurate clinical evaluation of blood glucose control in patients with T2DM.…”