Simultaneous determination of four components in Baige capsule by HPLC: application to pharmacokinetics and tissue distribution of normal and middle cerebral artery occlusion rats

LC-MS/MS analysis and pharmacokinetics of daidzein and its 7-O-glucuronide in rats after oral administration of 7-O-L-valyl carbamate prodrug

Background: A valine carbamate prodrug (7-P) was designed to enhance the low bioavailability of daidzein due to its low water solubility and membrane permeability. Here, we developed a high-throughput HPLC-MS/MS method to measure daidzein and its 7-O-glucuronide after oral administration of daidzein or 7-P. Materials & methods: A HPLC-MS/MS method was validated and successfully applied to assess the pharmacokinetic behavior of daidzein and its 7-O-glucuronide after orally administrating daidzein or 7-P. The validated method on selectivity, linearity (r ≥ 0.995), precision (relative standard deviation <11.4%), accuracy (relative error <7.1%), extraction recovery (>92.4%), matrix effect (<8.2%) and stability were satisfied. Conclusion: The proposed economical, rapid and sensitive method will be an alternative analytical procedure for daidzein and its metabolite in biological samples.

Imperatorin: A review of its pharmacology, toxicity and pharmacokinetics

As a naturally occurring furanocoumarin, the medicinal value of imperatorin has been studied more and more. We hope to provide useful information for the further development of imperatorin by analyzing the literature of imperatorin in recent years. By collating the literature on the pharmacology of imperatorin, we found that the pharmacological activity of imperatorin is wide and imperatorin can be used for anti-cancer, neuroprotection, anti-inflammatory, anti-hypertension and antibacterial. In addition, we found that some researchers confirmed the toxicity of imperatorin. Pharmacokinetic studies demonstrated that oxidation metabolism is the main metabolic pathways of imperatorin. At present, the shortcomings of research on imperatorin mainly include: most pharmacological studies are concentrated in vitro, lacking enough in vivo experimental data; more and more studies showed that imperatorin has synergistic effect with other drugs in anticancer and other aspects, but lacking the detailed explanation of the mechanism of the synergistic effect; imperatorin has side effect, but it lacks enough experimental conclusions. Based on the above defects, we believe that more in vivo experiments of imperatorin should be carried out in the future; future research need to explore synergistic mechanisms of imperatorin with other drugs, especially in anticancer; the dose affects both the pharmacological activity and the side effect of imperatorin. The relationship between the dose and the two aspects need to be further studied in order to reduce the side effect. In addition, through structural modification of imperatorin, it is possible to improve the treatment effect and reduce side effect.

Alteration of UDP-glucuronosyltransferase 1a1, 1a7 and P-glycoprotein expression in hepatic fibrosis rats and the impact on pharmacokinetics of puerarin

BACKGROUND

Puerarin, derived from a traditional Chinese herb Pueraria lobata (Willd.) Ohwi which was distributed globally and planted in most parts of China, has been extensively applied in patients with cardiovascular diseases in China. Yet a considerable proportion of the patients were accompanied with liver illnesses simultaneously because of all sorts of reasons.

HYPOTHESIS/PURPOSE

It had been implied by some previous research that the absorption and the metabolism of puerarin were susceptible to liver issues due to changed P-gp and Ugt1a level, but pharmacokinetics of puerarin under such conditions were few concerned. Our study aimed to make sure whether and how much the behavior of puerarin in vivo was affected by hepatic diseases, and to explore the potential mechanisms.

METHODS

A CCl₄ induced rat model of hepatic fibrosis (HF) was prepared and verified. Single low/high doses of oral and intravenous administration of puerarin to HF and normal rats were performed. Pharmacokinetics of puerarin were determined by a validated HPLC method. The expression of P-gp, Ugt1a1, and Ugt1a7 in both liver and intestines were determined by quantitative RT-PCR and Western blot analysis respectively.

RESULTS

The systemic exposure of puerarin in HF rats of experimental groups were found decreased remarkably except for that of the high dose intravenous group. Moreover, the expression of P-gp, Ugt1a1, and Ugt1a7 in liver and intestines of HF rats were figured out increased.

CONCLUSION

The results indicated that the HF originated overexpression of Ugt1a1, Ugt1a7, and P-gp level played important roles in pharmacokinetics of puerarin, suggested the clinical regimen of puerarin based on normal populations might be inappropriate for patients with chronic liver diseases. It was implied drugs whose absorption or elimination were related to P-gp, Ugt1a1, or Ugt1a7 might also be affected by hepatic illnesses.

The anti-inflammation effect of Baige capsule and its principal components mixture in MCAO rats

BACKGROUND

Baige (BG) is a compound Chinese herbal preparation, constituted of different position extracts (ethanol extracts from Pueraria lobate and SFE-CO₂ extracts from Radix Angelicae dahuricae) of P. lobata and A. dahurica to treat the brain injury in patients.

AIM

The goal of this study was to identify the neuroprotective properties of BG and its principal component mixture (PCM) and verify whether the material basis for BG is its PCM.

METHODS

Middle cerebral artery occlusion (MCAO) was operated on male Sprague-Dawley rat for 2 h, different doses of BG or PCM or vehicle were gavaged after 3 h of MCAO. Rats were sacrificed after 30 days treatment. Blood serum inflammation factors and NGF were detected by ELISA.

RESULTS

After 30 days of treatment, both BG and PCM interventions reduced the infarct volume, modified neurological severity score (mNSS) in rats, declined IL-1β and IL-6 levels in the serum, increased NGF level in the serum and recovered the number of Nissl body in injured brain.

CONCLUSIONS

Both BG and PCM exert equivalent levels of recovery effect in MCAO on rats; and PCM is the material foundation of BG. This recovery effect is associated with inflammatory inhibition and NGF production.

Preventive effects of imperatorin on perfluorohexanesulfonate-induced neuronal apoptosis via inhibition of intracellular calcium-mediated ERK pathway

Early life neuronal exposure to environmental toxicants has been suggested to be an important etiology of neurodegenerative disease development. Perfluorohexanesulfonate (PFHxS), one of the major perfluoroalkyl compounds, is widely distributed environmental contaminants. We have reported that PFHxS induces neuronal apoptosis via ERK-mediated pathway. Imperatorin is a furanocoumarin found in various edible plants and has a wide range of pharmacological effects including neuroprotection. In this study, the effects of imperatorin on PFHxS-induced neuronal apoptosis and the underlying mechanisms are examined using cerebellar granule cells (CGC). CGC were isolated from seven-day old rats and were grown in culture for seven days. Caspase-3 activity and TUNEL staining were used to determine neuronal apoptosis. PFHxS-induced apoptosis of CGC was significantly reduced by imperatorin and PD98059, an ERK pathway inhibitor. PFHxS induced a persistent increase in intracellular calcium, which was significantly blocked by imperatorin, NMDA receptor antagonist, MK801 and the L-type voltage-dependent calcium channel blockers, diltiazem and nifedipine. The activation of caspase-3 by PFHxS was also inhibited by MK801, diltiazem and nifedipine. PFHxS-increased ERK activation was inhibited by imperatorin, MK801, diltiazem and nifedipine. Taken together, imperatorin protects CGC against PFHxS-induced apoptosis via inhibition of NMDA receptor/intracellular calcium-mediated ERK pathway.