. Author manuscript; available in PMC: 2014 Sep 1.

Published in final edited form as: Curr Metabolomics. 2013 Sep 1;1(3):239–250. doi: 10.2174/2213235x1130100005

Table 1.

Effects of normal concentrations of fatty acids on the binding of sulfonylurea drugs to HSA and glycated HSA

Fatty Acid	Change in Free Drug Concentration^a
Fatty Acid	Acetohexamide	Gliclazide	Tolbutamide
Lauric acid (0.1–6 μM)
Normal HSA	0.2–10%	0.03–2.1%^b	0.04–2.7%
Glycated HSA	0.04–2.6%^b,^c	0.1–7%	0.02–1.0%^b,^c
Linoleic acid (20–93 μM)
Normal HSA	3.2–15%	5–24%	2.4–11%
Glycated HSA	6–29%^c	5–23%^c	8–38%
Myristic acid (3–24 μM)
Normal HSA	2.6–20%	0.6–4.6%^b	0.04–0.3%^b
Glycated HSA	1.0–8%^c	0.3–2.5%^c	0.5–4.2%^c
Oleic acid (33–182 μM)
Normal HSA	17–93%	−1.5–8%^a	9–35%^d
Glycated HSA	0.4–2.1%	9–21%^b	1.5–8%
Palmitic acid (25–171 μM)
Normal HSA	4.0–27%^d	4.3–29%	4.3–29%
Glycated HSA	1.5–10%^c	1.3–9%	5–36%^c
Stearic acid (6–57 μM)
Normal HSA	0.6–5%	4.4–41%	19–31%^d
Glycated HSA	0.6–5%^c	1.5–14%	2.8–25%^c

All of the indicated changes are relative to the free concentration measured for a drug in the absence of any fatty acid at pH 7.4 and 37°C; the given values represent an increase in the free drug concentration, except for the case of gliclazide in the presence of oleic acid and normal HSA.

All changes in the free drug concentration, except those indicated by this footnote, were significantly different at the 95% confidence level when comparing the results measured at the upper end of the normal fatty acid concentration range versus the results obtained when no fatty acid was present.

Non-linear regression or a combination of linear regions were used in this case because some curvature was noted in the corresponding plot of free drug concentration versus fatty acid concentration.