Effects of astragaloside IV on the pharmacokinetics of puerarin in rats

Pharmacokinetics of Dasatinib in Rats: a Potential Food-Drug Interaction with Naringenin

BACKGROUND AND OBJECTIVES

The novel tyrosine kinase inhibitor (TKI) dasatinib, a multitarget inhibitor of Bcr-Abl and Src family kinases, has been licensed for the treatment of Ph+ acute lymphoblastic leukemia and chronic myeloid leukemia. Many citrus-based foods include the flavonoid naringenin, which is commonly available. Dasatinib is a Cyp3a4, P-gp, and Bcrp1 substrate, which makes it sensitive to potential food-drug interactions. The concurrent use of naringenin may change the pharmacokinetics of dasatinib, which could result in adverse effects and toxicity. The present investigation examined the impact of naringenin on the pharmacokinetics interactions of DAS and proposes a possible interaction mechanism in Wistar rats.

METHODS

Rats were provided with a single oral dose of dasatinib (25 mg/kg) with or without naringenin pretreatment (150 mg/kg p.o. daily for 7 days, n = 6 in each group). Dasatinib was quantified in plasma by UHPLC MS/MS assay. Noncompartmental analysis was used to compute the pharmacokinetic parameters, and immunoblot was used to assess the protein expression in the hepatic and intestinal tissues.

RESULTS

Following 7 days of naringenin pretreatment, the plasma mean concentration of dasatinib was enhanced compared with without pretreatment. In rats that were pretreated with naringenin, the pharmacokinetics of the orally administered dasatinib (25 mg/kg) was shown to be significantly different from that of dasatinib given without pretreatment (p < 0.05). There was a significant enhancement in pharmacokinetic parameters elimination half-life (T1/2), time to maximum concentration ( Tmax), maximum concentration )Cmax), area under the concentration-time curve (AUC0-t), area under the moment curve (AUMC0-∞), and mean residence time (MRT) by 28.41%, 50%, 103.54%, 72.64%, 115.08%, and 15.19%, respectively (p < 0.05) and suppression in elimination rate constant (Kel), volume of distribution (Vd), and clearance (CL) by 21.09%, 31.13%, and 46.25%, respectively, in comparison with dasatinib alone group (p < 0.05). The enhancement in dasatinib bioavailability and systemic exposure resulted from the significant inhibition of Cyp3a2, Mdr1/P-gp, and Bcrp1 expression and suppression of the dasatinib hepatic and intestinal metabolism, which enhanced the rate of dasatinib absorption and decreased its elimination.

CONCLUSION

Concurrent use of naringenin-containing supplements, herbs, or foods with dasatinib may cause serious and potentially life-threatening drug interactions. Further studies are necessary to determine the clinical significance of these findings.

Astragaloside IV promotes exosome secretion of endothelial progenitor cells to regulate PI3KR2/SPRED1 signaling and inhibit pyroptosis of diabetic endothelial cells

BACKGROUND AIMS

Treating chronic non-healing diabetic wounds and achieving complete skin regeneration has always been a critical clinical challenge.

METHODS

In order to address this issue, researchers conducted a study aiming to investigate the role of miR-126-3p in regulating the downstream gene PIK3R2 and promoting diabetic wound repair in endothelial progenitor cell (EPC)-derived extracellular vesicles. The study involved culturing EPCs with astragaloside IV, transfecting them with miR-126-3p inhibitor or mock plasmid, interfering with high glucose-induced damage in human umbilical vein endothelial cells (HUVECs) and treating diabetic skin wounds in rats.

RESULTS

The healing of rat skin wounds was observed through histological staining. The results revealed that treatment with miR-126-3p-overexpressing EPC-derived extracellular vesicles accelerated the healing of rat skin wounds and resulted in better tissue repair with slower scar formation. In addition, the transfer of EPC-derived extracellular vesicles with high expression of miR-126-3p to high glucose-damaged HUVECs increased their proliferation and invasion, reduced necrotic and apoptotic cell numbers and improved tube formation. In this process, the expression of angiogenic factors vascular endothelial growth factor (VEGF)A, VEGFB, VEGFC, basic fibroblast growth factor and Ang-1 significantly increased, whereas the expression of caspase-1, NRLP3, interleukin-1β, inteleukin-18, PIK3R2 and SPRED1 was suppressed. Furthermore, miR-126-3p was able to target and inhibit the expression of the PIK3R2 gene, thereby restoring the proliferation and migration ability of high glucose-damaged HUVEC.

CONCLUSIONS

In summary, these research findings demonstrate the important role of miR-126-3p in regulating downstream genes and promoting diabetic wound repair, providing a new approach for treating chronic non-healing diabetic wounds.

Pharmacokinetic study on the co-administration of abemaciclib and astragaloside IV in rats

CONTEXT

The co-administration of abemaciclib and astragaloside IV might occur in the treatment of breast cancer.

OBJECTIVE

This study evaluates the interaction between abemaciclib and astragaloside IV in rats and describes the potential mechanism.

MATERIALS AND METHODS

Male Sprague Dawley rats were randomly divided into four groups: single dose of abemaciclib (control), abemaciclib + 50 mg/kg/d astragaloside IV, abemaciclib + 100 mg/kg/d astragaloside IV, and abemaciclib + 150 mg/kg/d astragaloside IV. Abemaciclib and astragaloside IV were orally administrated, and astragaloside IV was pre-administrated for 7 d in the co-administrated groups. The pharmacokinetics and transport of abemaciclib were assessed in the absence or presence of astragaloside IV. In mechanism, the activity of CYP3A4 was estimated in human liver microsomes in the presence of astragaloside IV.

RESULTS

Astragaloside IV significantly increased the C_max (from 991.5 ± 116.99 up to 2308.5 ± 55.29 μg/L) and AUC (from 24.49 ± 2.86 up to 66.14 ± 1.17 μg/mL × h) and prolonged the t_1/2 (from 19.85 ± 4.65 up to 66.17 ± 28.73 h) of abemaciclib, and the effect was enhanced with the increasing astragaloside IV concentration. Astragaloside IV also suppressed the transport of abemaciclib with the efflux ratio decreasing to 1.35. Astragaloside IV suppressed the activity of CYP3A4 with an IC₅₀ value of 21.78 μM.

DISCUSSION AND CONCLUSIONS

The co-administration of abemaciclib and astragaloside IV induced the increasing systemic exposure of abemaciclib through the inhibition of CYP3A4. Further clinical validations could be carried out according to the study design of the present investigation.

Puerarin: A review of its mechanisms of action and clinical studies in ophthalmology

BACKGROUND

Pueraria is the common name of the dried root of either Pueraria montana var. lobata (Willd.) Maesen & S.M.Almeida ex Sanjappa & Predeep (syn. Pueraria lobata (Willd.) Ohwi) or Pueraria montana var. thomsonii (Benth.) M.R.Almeida (syn. Pueraria thomsonii Benth.). Puerarin is a C-glucoside of the isoflavone daidzein extracted from Pueraria. It has been widely investigated to explore its therapeutic role in eye diseases and the molecular mechanisms.

PURPOSE

To collect the available literature from 2000 to 2022 on puerarin in the treatment of ocular diseases and suggest the future required directions to improve its medicinal value.

METHOD

The content of this review was obtained from databases such as Web of Science, PubMed, Google Scholar, China National Knowledge Infrastructure (CNKI), and the Wanfang Database.

RESULTS

The search yielded 428 articles, of which 159 articles were included after excluding duplicate articles and articles related to puerarin but less relevant to the topic of the review. In eleven articles, the bioavailability of puerarin was discussed. Despite puerarin possesses diverse biological activities, its bioavailability on its own is poor. There are 95 articles in which the therapeutic mechanisms of puerarin in ocular diseases was reported. Of these, 54 articles discussed the various signalling pathways related to occular diseases affected by puerarin. The other 41 articles discussed specific biological activities of puerarin. It plays a therapeutic role in ophthalmopathy via regulating nuclear factor kappa-B (NF-ĸB), mitogen-activated protein kinases (MAPKs), PI3K/AKT, JAK/STAT, protein kinase C (PKC) and other related pathways, affecting the expression of tumour necrosis factor α (TNF-α), interleukin-1β (IL-1β), intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), superoxide dismutase (SOD), B-cell lymphoma-2 (Bcl-2) and other cytokines resulting in anti-inflammatory, antioxidant and anti-apoptotic effects. The clinical applications of puerarin in ophthalmology were discussed in 25 articles. Eleven articles discussed the toxicity of puerarin. The literature suggests that puerarin has a good curative effect and can be used safely in clinical practice.

CONCLUSION

This review has illustrated the diverse applications of puerarin acting on ocular diseases and suggested that puerarin can be used for treating diabetic retinopathy, retinal vascular occlusion, glaucoma and other ocular diseases in the clinic. Some ocular diseases are the result of the combined action of multiple factors, and the effect of puerarin on different factors needs to be further studied to improve a more complete mechanism of action of puerarin. In addition, it is necessary to increase the number of subjects in clinical trials and conduct clinical trials for other ocular diseases. The information presented here will guide future research studies.

Advances in Pharmacokinetic Mechanisms of Transporter-Mediated Herb-Drug Interactions

As the use of herbs has become more popular worldwide, there are increasing reports of herb-drug interactions (HDIs) following the combination of herbs and drugs. The active components of herbs are complex and have a variety of pharmacological activities, which inevitably affect changes in the pharmacokinetics of chemical drugs in vivo. The absorption, distribution, metabolism, and excretion of drugs in vivo are closely related to the expression of drug transporters. When the active components of herbs inhibit or induce the expression of transporters, this can cause changes in substrate pharmacokinetics, resulting in changes in the efficacy and toxicity of drugs. In this article, the tissue distribution and physiological functions of drug transporters are summarized through literature retrieval, and the effects of herbs on drug transporters and the possible mechanism of HDIs are analyzed and discussed in order to provide ideas and a reference for further guiding of safe clinical drug use.

Influence of verapamil on the pharmacokinetics of rotundic acid in rats and its potential mechanism

CONTEXT

Rotundic acid (RA), a plant-derived pentacyclic triterpene acid, has been reported to possess extensive pharmacological activities. The poor bioavailability limits its further development and potential clinic application.

OBJECTIVE

To clarify the potential mechanism for poor oral bioavailability.

MATERIALS AND METHODS

The single-dose pharmacokinetics of orally administered RA (10 mg/kg) in Sprague-Dawley rats without or with verapamil (25 or 50 mg/kg) were investigated. Additionally, MDCKII-MDR1 and Caco-2 cell monolayers, five recombinant human cytochrome P450 (rhCYP) enzymes (1A2, 2C8, 2C9, 2D6 and 3A4), and rat liver microsomes were also conducted to investigate its potential mechanism.

RESULTS

Verapamil could significantly affect the plasma concentration of RA. Co-administered verapamil at 25 and 50 mg/kg, the AUC_0-∞ increased from 432 ± 64.2 to 539 ± 53.6 and 836 ± 116 ng × h/mL, respectively, and the oral clearance decreased from 23.6 ± 3.50 to 18.7 ± 1.85 and 12.2 ± 1.85 L/h/kg, respectively. The MDCKII-MDR1 cell assay showed that RA might be a P-gp substrate. The rhCYPs experiments indicated that RA was mainly metabolized by CYP3A4. Additionally, verapamil could increase the absorption of RA by inhibiting the activity of P-gp, and slow down the intrinsic clearance of RA from 48.5 ± 3.18 to 12.0 ± 1.06 µL/min/mg protein.

DISCUSSION AND CONCLUSIONS

These findings indicated that verapamil could significantly affect the pharmacokinetic profiles of RA in rats. It was demonstrated that P-gp and CYP3A were involved in the transport and metabolism of RA, which might contribute to the low oral bioavailability of RA.

Evaluation of the digestion and transport profiles and potential immunocompetence of puerarin and its acylated derivatives

Acylation has become one of the most widely used methods to improve the lipid solubility and bioavailability of flavonoids. In this study, puerarin acid esters (PAES) with different chain lengths were synthesized via biocatalytic acylation. This was the first study to evaluate the digestion and transport profiles and immunocompetence of PAES. The relationship between the digestion and transport profiles and potential immunocompetence of the acylated derivatives in Caco-2 cell monolayers was also explored. Puerarin and PAES remained stable in gastric phases, whereas different degrees of hydrolysis of PAES were found in the intestine. PAES with less than 12 carbon chains were positively correlated with the degree of hydrolysis, while those with more than 12 carbon chains showed higher resistance to hydrolysis by the artificial human digestive juice. The apparent permeability coefficients of puerarin, puerarin acetate, puerarin propanoate, puerarin butyrate, puerarin hexanoate, puerarin octanate and puerarin laurate were 1.62 ± 0.09, 1.70 ± 0.15, 1.89 ± 0.19, 1.86 ± 0.18, 2.29 ± 0.12, 4.06 ± 1.01 and 2.32 ± 0.88 × 10-6 cm s-1, respectively, in Caco-2 cell monolayers. The results of the immune factor assays indicated that puerarin propanoate, puerarin hexanoate and puerarin myristate could significantly promote the secretion of IL-6, TNF-α and IL-10. These findings suggested that a better absorption could be predicted after oral intake using PAES. Meanwhile, the concentration of esters and their metabolites (puerarin) found in the digestion and transport profiles directly affected their potential immunocompetence.

Effects of curcumin on the pharmacokinetics of amlodipine in rats and its potential mechanism

Context: Hyperlipidaemia and hypertension are often treated together with curcumin and amlodipine. It is necessary to investigate the drug-drug interaction between curcumin and amlodipine.Objective: The interaction between curcumin and amlodipine was investigated in rats and with rat liver microsomes.Methods: The pharmacokinetics of amlodipine (1 mg/kg) was investigated in rats with or without curcumin pre-treatment (2 mg/kg), six rats in each group. The metabolic stability of amlodipine was investigated with rat liver microsomes.Results: Curcumin significantly increased the C_max (26.19 ± 2.21 versus 17.80 ± 1.56 μg/L), AUC_(0-t) (507.27 ± 60.23 versus 238.68 ± 45.59 μg·h/L), and t_1/2 (14.69 ± 1.64 versus 11.43 ± 1.20 h) of amlodipine (p < 0.05). The metabolic stability of amlodipine was significantly increased with the half-life time in rat liver microsomes increased from 34.23 ± 3.33 to 44.15 ± 4.12 min, and the intrinsic rate decreased from 40.49 ± 3.26 to 31.39 ± 2.78 μL/min/mg protein.Discussion and conclusions: These results indicated that drug-drug interaction might appear during the co-administration of curcumin and amlodipine. The potential mechanism may be due to the inhibition of CYP3A4 by curcumin. Thus, this interaction should be given special attention in the clinic and needs further experiments to characterize the effect in humans.

Effects of puerarin on the pharmacokinetics of astragaloside IV in rats and its potential mechanism

Context: Puerarin and astragaloside IV (AS-IV) are sometimes used together for the treatment of disease in Chinese clinics, however, the drug-drug interaction between puerarin and AS-IV is still unknown.Objective: This study investigates the effects of puerarin on the pharmacokinetics of astragaloside IV in rats and clarifies its main mechanism.Materials and methods: The pharmacokinetic profiles of oral administration of astragaloside IV (20 mg/kg) in Sprague-Dawley rats, with or without pre-treatment of puerarin (100 mg/kg/day for 7 days) were investigated. The effects of puerarin on the transport and metabolic stability of AS-IV were also investigated using Caco-2 cell transwell model and rat liver microsomes.Results: The results showed that puerarin could significantly increase the peak plasma concentration (from 48.58 ± 7.26 to 72.71 ± 0.62 ng/mL), and decrease the oral clearance (from 47.5 ± 8.91 to 27.15 ± 9.27 L/h/kg) of AS-IV. The Caco-2 cell transwell experiments indicated that puerarin could decrease the efflux ratio of astragaloside IV from 1.89 to 1.26, and the intrinsic clearance rate of astragaloside IV was decreased by the pre-treatment with puerarin (34.8 ± 2.9 vs. 41.5 ± 3.8 μL/min/mg protein).Discussion and conclusions: These results indicated that puerarin could significantly change the pharmacokinetic profiles of astragaloside IV, via increasing the absorption of astragaloside IV or inhibiting the metabolism of astragaloside IV in rats.

Effects of naringenin on the pharmacokinetics of tofacitinib in rats

Context: Naringenin and tofacitinib are often used together for treatment of rheumatoid arthritis in Chinese clinics.Objective: This experiment investigates the effect of naringenin on the pharmacokinetics of tofacitinib in rats.Materials and methods: Twelve Sprague-Dawley rats were randomly divided into two groups (experimental group and control group). The experimental group was pre-treated with naringenin (150 mg/kg/day) for two weeks before dosing tofacitinib, and equal amounts of CMC-Na solution in the control group. After a single oral administration of 5 mg/kg of tofacitinib, 50 μL blood samples were directly collected into 1.5 mL heparinized tubes via the caudal vein at 0.083, 0.5, 1, 2, 3, 4, 6, 8, 10, 12 and 24 h. The plasma concentration of tofacitinib was quantified by UPLC/MS-MS.Results: Results indicated that naringenin could significantly affect the pharmacokinetics of tofacitinib. The AUC_0-24 of tofacitinib was increased from 1222.81 ± 222.07 to 2016.27 ± 481.62 ng/mL/h, and the difference was significant (p < 0.05). Compared with the control group, the T_max was increased from 0.75 ± 0.29 to 3.00 ± 0.00 h (p < 0.05), and the MRT_(0-24) was increased from 4.90 ± 0.51 to 6.57 ± 0.66 h (p < 0.05), but the clearance was obviously decreased from 4.10 ± 0.72 to 2.42 ± 0.70 L/h/kg (p < 0.05) in experimental group. Although the C_max and t_1/2 of tofacitinib were increased, there were no significant differences (p > 0.05).Conclusions: This research demonstrated a drug-drug interaction between naringenin and tofacitinib possibly when preadministered with naringenin; thus, we should pay attention to this possibility in the clinic.

Effect of verapamil on the pharmacokinetics of hydroxycamptothecin and its potential mechanism

Context: Hydroxycamptothecin (HCPT) has antitumor activity in various cancers, but its poor bioavailability and efflux limit its clinical application. Verapamil has been demonstrated to improve the bioavailability of many drugs. However, the effect of verapamil on the pharmacokinetics of HCPT was not clear.Objective: The effect of verapamil on the pharmacokinetics of HCPT was investigated to clarify the drug-drug interaction between HCPT and verapamil.Materials and methods: The pharmacokinetic profiles of oral administration of HCPT (50 mg/kg) in two group of Sprague-Dawley rats (six rats each), with pre-treatment of verapamil (10 mg/kg/day) for 7 days were investigated, with the group without verapamil pre-treatment as control. Additionally, the metabolic stability and transport of HCPT in the presence or absence of verapamil were also investigated with the employment of the rat liver microsomes and Caco-2 cell transwell model.Results: Verapamil significantly increased the peak plasma concentration (from 91.97 ± 11.30 to 125.30 ± 13.50 ng/mL), and decrease the oral clearance (from 63.85 ± 10.79 to 32.95 ± 6.17 L/h/kg). The intrinsic clearance rate was also significantly decreased (from 39.49 ± 0.42 to 28.64 ± 0.30 μL/min/mg protein) by the preincubation of verapamil. The results of Caco-2 cell transwell experiments showed the efflux of HCPT was inhibited by verapamil, as the efflux ratio decreased from 1.82 to 1.21.Discussion and conclusions: The system exposure of HCPT was increased by verapamil. Verapamil may exert this effect through inhibiting the activity of CYP3A4 or P-gp, which are related to the metabolism and transport of HCPT.

In vitro inhibitory effect of lysionotin on the activity of cytochrome P450 enzymes

CONTEXT

Lysionotin, a major extraction of Lysionotus pauciflorus Maxim (Gesneriaceae), has a variety of pharmacological properties commonly used in the treatment of lung disease. A study of lysionotin on the activity of human liver cytochrome P450 (CYP) enzymes can provide guidance on the clinical application of lysionotin.

OBJECTIVE

This study investigated the interaction between lysionotin and CYPs.

MATERIAL AND METHOD

The effects of 100 μM lysionotin on eight human liver CYP isoforms (i.e., 1A2, 3A4, 2A6, 2E1, 2D6, 2C9, 2C19 and 2C8) were investigated in vitro using human liver microsomes (HLMs) with specific inhibitor as positive control and untreated HLMs as control. Meanwhile, the enzyme kinetic parameters were calculated. A time-dependent study was performed with a time interval of 5 min in 30 min.

RESULTS

Lysionotin was found to inhibit the activity of CYP3A4, 2C19, and 2C8, with IC₅₀ values of 13.85, 24.95, and 30.05 μM, respectively. The inhibition of CYP3A4 was performed in a non-competitive manner with the Ki value of 6.83 μM, while the inhibition of CYP2C19 and 2C8 was performed in a competitive manner with Ki values of 12.41 and 14.51 μM. Moreover, it was found that the inhibition of CYP3A4 was time-dependent with K _I/K _inact value of 6.618/0.048 min/μM. Discussion and conclusions: The in vitro inhibitory effect of lysionotin on the activity of CYP3A4, 2C19, and 2C8 indicated potential drug interactions between lysionotin and drugs metabolised by CYP3A4, 2C19, and 2C8. Further in vivo experiments are needed to assess the potential interactions.

Inhibitory Effect of Imperatorin on the Pharmacokinetics of Diazepam In Vitro and In Vivo

Background

Diazepam is a benzodiazepine drug used to treat anxiety, insomnia, and muscle spasms. Imperatorin is a phytochemical isolated from medicinal plants and is widely used in herbal medicine. The aim of this study was to investigate the interactions between imperatorin and diazepam in vitro and in vivo and to provide evidence-based guidance for the safe clinical use of the drug.

Methods

In vitro inhibition of imperatorin was assessed by incubating rat liver microsomes with diazepam to determine IC₅₀ values and the type of inhibition. For in vivo assessment, six rats were pretreated with 50 mg/kg imperatorin for two weeks, six were administered saline, and a single dose of 10 mg/kg diazepam was administered orally to both groups 30 min after the administration of imperatorin.

Results

Imperatorin inhibited the in vitro metabolism of diazepam via the competitive mechanism of CYP450. The IC₅₀ values of imperatorin to nordazepam and temazepam were 1.54 μM and 1.80 μM, respectively. The inhibitory constant values for temazepam and nordazepam were 1.24 μM and 1.29 μM, respectively. Long-term administration of imperatorin significantly increased the AUC_(0-12h), AUC_(0-∞), and Cmax of diazepam, while Vz/F and CLz/F were decreased significantly (P < 0.05). In turn, the AUC_(0-12h), AUC_(0-∞), and Cmax of nordazepam and temazepam decreased significantly, and Vz/F and CLz/F increased significantly (P < 0.05).

Conclusions

This study demonstrates that imperatorin inhibits the metabolism of diazepam both in vitro and in vivo. These results indicated that more attention should be paid when taking diazepam together with food or herbs containing IMP, although further investigation is still needed.

Marked decrease of tacrolimus blood concentration caused by compound Chinese herbal granules in a patient with refractory nephrotic syndrome

WHAT IS KNOWN AND OBJECTIVE

The blood concentration of tacrolimus can be affected by co-administrated drugs. The objective is to draw more attention to herb-drug interactions in China, where herbal medicines are commonly used.

CASE DESCRIPTION

The blood concentration of tacrolimus in a girl with refractory nephrotic syndrome decreased nearly a half despite no change in dose. Nebulizer therapy, cyclophosphamide and a compound Chinese herbal medicine were the only additional treatments than usual.

WHAT IS NEW AND CONCLUSION

The most possible cause of the decrease in tacrolimus concentration was the administration of Radix Astragali among compound Chinese herbal medicine granules.

Comparative Pharmacokinetic Profiles of Puerarin in Rat Plasma by UHPLC-MS/MS after Oral Administration of Pueraria lobata Extract and Pure Puerarin

Puerarin is the main biologically active isoflavone in Pueraria lobata and has a wide range of biological activities. However, due to its poor water solubility and low oral bioavailability, its clinical applications are restricted. Compared with puerarin, the Pueraria lobata extract (PLE) has better water solubility, lower toxicity, and less side effects. In this study, the pharmacokinetics of orally administered puerarin (100 mg/kg) and PLE (763 mg/kg, equivalent to 100.0 mg/kg of puerarin) to rats was investigated by the UHPLC-MS/MS method. Results showed that when the rats were administered PLE, the area under the concentration-time curve from zero to infinity (AUC _0-inf ) dramatically increased from 219.83 ± 64.37 μg h/L to 462.62 ± 51.74 μg h/L (p < 0.01). The elimination half-time (t _1/2 ) also increased from 1.60 ± 0.38 h to 12.04 ± 5.10 h (p < 0.01). The maximum concentration (C _max) of puerarin decreased from 101.64 ± 41.82 ng/mL to 48.64 ± 21.47 ng/mL (p < 0.01), and time to reach the maximum plasma concentration (T _max) of puerarin decreased from 1.46 ± 1.08 h to 0.54 ± 0.30 h (p < 0.01). Results indicated that the pharmacokinetics of puerarin in Pueraria lobata may be dramatically different from pure puerarin in the plasma of rat, and oral bioavailability of puerarin may be increased when PLE was administrated to rats.

Pharmacokinetics and drug delivery systems for puerarin, a bioactive flavone from traditional Chinese medicine

Pueraria lobata (Willd.) Ohwi is a medicinal and edible homologous plant with a long history in China. Puerarin, the main component isolated from the root of Pueraria lobata, possesses a wide range of pharmacological properties. Daidzein and glucuronides are the main metabolites of puerarin and are excreted in the urine and feces. As active substrates of P-gp, multidrug resistance-associated protein and multiple metabolic enzymes, the pharmacokinetics of puerarin can be influenced by different pathological conditions and drug-drug interactions. Due to the poor water-solubility and liposolubility, the applications of puerarin are limited. So far, only puerarin injections and eye drops are on the market. Recent years, researches on improving the bioavailability of puerarin are developing rapidly, various nanotechnologies and preparation technologies including microemulsions and SMEDDS, dendrimers, nanoparticles and nanocrystals have been researched to improve the bioavailability of puerarin. In order to achieve biocompatibility and desired activity, more effective quality evaluations of nanocarriers are required. In this review, we summarize the pharmacokinetics and drug delivery systems of puerarin up to date.