Open AccessRelationship of hemoglobin level and plasma coproporphyrin‐I concentrations as an endogenous probe for phenotyping OATP1B
Author(s) -
Suzuki Yosuke,
Sasamoto Yuri,
Koyama Teruhide,
Yoshijima Chisato,
Oda Ayako,
Nakatochi Masahiro,
Kubo Michiaki,
Momozawa Yukihide,
Uehara Ritei,
Ohno Keiko
Publication year - 2021
Publication title -
clinical and translational science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.303
H-Index - 44
eISSN - 1752-8062
pISSN - 1752-8054
DOI - 10.1111/cts.12996
Subject(s) - hemoglobin , medicine , heme , chemistry , plasma concentration , endogeny , biomarker , endocrinology , basal (medicine) , population , blood plasma , biochemistry , biology , enzyme , environmental health , insulin
Plasma coproporphyrin‐I (CP‐I) concentration is used as a sensitive and selective endogenous probe for phenotyping organic anion transporting polypeptides 1B (OATP1B) activity in many studies. CP‐I is produced in the process of heme synthesis, but the relationship between plasma CP‐I concentrations and heme synthesis activity is unknown. In this study, we evaluated the relationship between plasma CP‐I concentration and hemoglobin level as a biomarker of heme synthesis activity. The data of 391 subjects selected from the Japanese general population were analyzed. One hundred twenty‐six participants had OATP1B1*15 allele, 11 of whom were homozygous ( OATP1B1*15 / *15 ). Multiple regression analysis identified hemoglobin level as an independent variable associated with plasma CP‐I concentration ( p < 0.0001). A significant positive correlation was observed between hemoglobin level and plasma CP‐I concentration in participants without OATP1B1*15 allele ( n = 265; r s = 0.35, p < 0.0001) and with OATP1B1*15 allele ( n = 126; r s =0.27, p = 0.0022). However, Kruskal–Wallis test showed no large difference in Kruskal–Wallis statistics between the distribution of plasma CP‐I concentrations and that of ratio of plasma CP‐I to hemoglobin among six OATP1B1 polymorphism groups. These findings suggest that the hemoglobin level seems to reflect biosynthesis of CP‐I. However, correction by hemoglobin level is not required when using basal plasma CP‐I concentration for phenotyping OATP1B activity.