Pharmacokinetic and Pharmacodynamic Interaction of Boswellic Acids and Andrographolide With Glyburide in Diabetic Rats: Including Its PK/PD Modeling

Phytother Res. 2016 Mar;30(3):496-502. doi: 10.1002/ptr.5556. Epub 2016 Jan 13.


The effect of boswellic acids (BA) and andrographolide (AD) on the pharmacokinetics and pharmacodynamics of glyburide in normal as well as in streptozotocin-induced diabetic rats was studied. In normal and diabetic rats, the combination of glyburide with BA or AD increased significantly (p < 0.01) all the pharmacokinetic parameters, such as Cmax, AUC0-n, AUCtotal, t1/2, and mean residence time, and decreased the clearance, Vd, markedly as compared with the control group. In rat liver, microsomes BA and AD have shown CYP3A4 inhibitory activity significantly (p < 0.01), compared with the vehicle group. The increase in hypoglycemic action by concomitant administration of glyburide with BA or AD was more in diabetic rats than when the drugs were used singly and with the control group, which suggests the enhancement of glucose reduction capacity of glyburide in diabetic rats along with BA or AD. In PK/PD modeling of BA and AD with glyburide, the predicted PK and PD parameters are in line with the observed PK and PD parameters. The results revealed that BA and AD led to the PK/PD changes because of glyburide-increased bioavailability and because of the inhibition of CYP3A4 enzyme. In conclusion, add-on preparations containing BA or AD may increase the bioavailability of glyburide, and hence the dose should be monitored.

Keywords: CYP3A4; PK/PD modeling; andrographolide; boswellic acids; glyburide.

MeSH terms

  • Animals
  • Area Under Curve
  • Biological Availability
  • Cytochrome P-450 CYP3A / metabolism
  • Diabetes Mellitus, Experimental* / drug therapy
  • Diterpenes / pharmacology*
  • Glyburide* / pharmacokinetics
  • Glyburide* / pharmacology
  • Herb-Drug Interactions*
  • Hypoglycemic Agents* / pharmacokinetics
  • Hypoglycemic Agents* / pharmacology
  • Liver / drug effects
  • Liver / metabolism
  • Male
  • Phytotherapy
  • Plant Extracts / pharmacology*
  • Rats, Wistar
  • Reference Values
  • Triterpenes / pharmacology*


  • Diterpenes
  • Hypoglycemic Agents
  • Plant Extracts
  • Triterpenes
  • andrographolide
  • boswellic acid
  • Cytochrome P-450 CYP3A
  • Glyburide