Concentration Of Puerarin Research Articles

Preparation of Puerarin Long Circulating Liposomes and its Effect on Osteoporosis in Castrated Rats

Osteoporosis is a disease that causes low bone mass and deterioration of bone microarchitecture. Puerarin is a natural isoflavone compound that has been shown to possess anti-inflammatory, antioxidant and ameliorative effects on osteoporosis with less adverse reactions. However, its fast metabolism and low oral bioavailability limit its application. This study aimed to prepare d-α-tocopherol polyethylene glycol 1000 succinate (TPGS)- modified Puerarin Long Circulating Liposomes (TPGS-Puerarin-liposomes), in order to improve the oral bioavailability of puerarin, before evaluation of its pharmacological activity in vitro and in vivo. We employed film dispersion method to develop TPGS-Puerarin-liposomes before appropriate characterizations. Afterwards, we utilized in vivo imaging, pharmacokinetic analysis and in vitro drug release testing to further evaluate the in vivo and in vitro delivery efficiency. In addition, we established a castrated osteoporosis rat model to observe the changes in femur tissue structure and bone micromorphology via hematoxylin-eosin (HE) staining and Micro Computed Tomography (Micro CT). Besides, levels of oxidative stress and inflammatory indicators, as well as expression of wnt/β-catenin pathway-related proteins were detected. In terms of physiochemical properties, the respective mean particle size (PS) and zeta potential (ZP) of TPGS-Puerarin-liposomes were 76.63±0.59 nm and -25.54±0.11 mV. The liposomal formulation exhibited encapsulation efficiency (EE) of 95.08±0.25% and drug loading (DL) of 7.84±0.07%, along with excellent storage stability. Compared with free drugs, the TPGS-Puerarin-liposomes demonstrated a sustained release effect and could increase blood concentration of puerarin in rats, thereby significantly improving its bioavailability. Also, in vivo studies have confirmed potential of the liposomes to promote bone tissue targeting and accumulation of puerarin, coupled with significant improvement of the osteoporotic status. Besides, the liposomes could also reduce levels of oxidative stress and inflammatory factors in serum and bone tissue. Additionally, we discovered that TPGS-Puerarin-liposomes increased Wnt, β-catenin and T-cell factor (TCF) expressions at protein level in the wnt/β-catenin signaling pathway. This study has demonstrated the potential of TPGS-Puerarin-liposomes for treatment of osteoporosis.

Green synthesis of puerarin acid esters and their oral absorption evaluation in vivo

Design and synthesis of prodrugs is an effective strategy to develop new drugs. Puerarin is well-known for its pharmacological properties in the treatment of many cardiovascular and cerebrovascular related diseases. To cope with its poor liposolubility that limited practical applications, we successfully developed a new type of clean and efficient esterification medium for acylation modification of puerarin and studied the relative oral absorption, including pharmacokinetics, tissue distribution and metabolite after oral taking of puerarin acid esters in comparison with free puerarin in rats. In the 1-Ethyl-3-Methylimidazoliumacetate, puerarin had the good solubility, and the reaction showed great initial rate (46.71 mmol/(L*h)) and substrate conversion (63.91%). The results of oral absorption showed that the administration of long-chain fatty acid esters of puerarin, puerarin hexanoate and puerarin myristate, resulted in significantly higher levels of puerarin in the plasma and tissues, especially in the heart, cerebral cortex, hippocampus and corpus striatum. Overall, these findings collectively supported that puerarin acid esters administration led to greater circulating concentration of puerarin and had a reduced excretion rate, providing significant advantages and theoretical basis for their application in functional foods and pharmaceutical industries.

Enhanced treatment for cerebral ischemia-reperfusion injury of puerarin loading liposomes through neutrophils-mediated targeted delivery

The recovery of blood circulation following cerebral infarction-associated thrombolysis brings new damage to the brain, which is cerebral ischemia-reperfusion injury (CIRI). Inflammation is the main pathological mechanism of CIRI. The inflammatory response triggered by cerebral ischemia-reperfusion provides neutrophils with a special opportunity to facilitate drug delivery to the site of ischemic penumbra through the chemotaxis of inflammatory factors by neutrophils. Puerarin is an isoflavone derivative with a significant neuroprotective effect in vitro. But the blood-brain barrier (BBB) impedes its therapeutic efficacy on CIRI within the brain. Inspired by the pathological process, we have used neutrophils as carriers to enhance the BBB penetration of liposomes loaded with puerarin and improve the concentration of puerarin in the brain parenchyma in this study. These results showed that puerarin-containing liposomes were released in response to inflammatory conditions associated with brain injury to enhance the neuroprotection effect at the ischemic penumbra.

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 (AUC0-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 (t1/2) also increased from 1.60 ± 0.38 h to 12.04 ± 5.10 h (p < 0.01). The maximum concentration (Cmax) 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 (Tmax) 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.

Effects of astragaloside IV on the pharmacokinetics of puerarin in rats

Radix astragali and puerarin are always used together for cardiovascular disease in China clinics.This study investigates the effects of astragaloside IV (AS-IV, the main components of radix astragali) on the pharmacokinetics of puerarin in rats.The pharmacokinetics of orally administered puerarin (50 mg/kg) with or without AS-IV pretreatment (100 mg/kg/day for seven days) were investigated. The plasma concentration of puerarin was determined using LC–MS/MS method, and the pharmacokinetics profiles were calculated and compared. Caco-2 cell transwell model was also used to investigate the effects of AS-IV on the transport pf puerarin.The results showed that when the rats were pretreated with AS-IV, the maximum concentration (Cmax) of puerarin decreased from 760 to 467 ng/mL (p < .05, n = 6, 90% CI, 293 ± 61.28), and the area under the concentration-time curve from zero to infinity (AUC0–inf) also decreased from 4097 to 2330 μg·h/L (p < .05, n = 6). The oral clearance of puerarin increased significantly from 11.9 to 22.4 L/h/kg (p < .05, n = 6). The Caco-2 cell transwell experiments indicated that AS-IV could increase the efflux ratio of puerarin from 1.81 to 2.79 through inducing the activity of P-gp.In conclusion, these results indicated that AS-IV could affect the pharmacokinetics of puerarin, possibly by decreasing the systemic exposure of puerarin by inducing the activity of P-gp.

Effects of verapamil on the pharmacokinetics of puerarin in rats

The oral bioavailability of puerarin is poor which hindered its clinical performance.This study investigates the effects of verapamil on the pharmacokinetics of puerarin in rats.The pharmacokinetics of orally administered puerarin (50 mg/kg) with or without verapamil pretreatment (10 mg/kg/day for 7 days) were investigated. The plasma concentration of puerarin was determined using LC-MS/MS method, and the pharmacokinetics profiles were calculated and compared. Caco-2 cell transwell model was also used to investigate the effects of verapamil on the transport pf puerarin.The results showed that when the rats were pretreated with verapamil, the maximum concentration (Cmax) of puerarin increased from 683.7 ± 51.2 to 933.5 ± 75.8 ng/mL (p < 0.05), and the area under the concentration-time curve from zero to infinity (AUC0-inf) also increased from 3687.3 ± 444.6 to 5006.1 ± 658.6 μg·h/L (p < 0.05). The Caco-2 cell transwell experiments indicated that verapamil could decrease the efflux ratio of puerarin from 1.90 to 1.19 through inhibiting the activity of P-gp.In conclusion, these results indicated that verapamil could affect the pharmacokinetics of puerarin, possibly by increasing the systemic exposure of puerarin by inhibiting the activity of P-gp.

An Electrochemical Sensor Based on Ultra-Micro Activated Carbon for the Determination of Puerarin

After intensely ultrasonic cracking, activated carbon obtained larger specific surface area in the premise of the high electric conductivity being maintained, which has provided a prerequisite for the construction of highly sensitive electrochemical sensors. An electrochemical sensor for sensitive analysis of puerarin in Radix Puerariae was successfully constructed using the prepared ultra-micro activated carbon in this work. The electrochemical behavior of puerarin on the sensor was investigated by cyclic voltammetry and differential pulse voltammetry. Moreover, the conditions of sensor preparing and puerarin detecting were optimized. Under the optimal conditions, the oxidation peak current increased linearly with the concentration of puerarin in the range of 2.4 × 10−7 mol L−1∼1.54 × 10−5 mol L−1, and the detection limit was 6.4 × 10−8 mol L−1. In addition, the proposed sensor also exhibited good reproducibility, stability and selectivity. With superior performance in sample analysis, the proposed method would not only provide a new way for rapid and sensitive detection of puerarin, but also give a new idea for the application of activated carbon materials in the field of electrochemical sensors.

Distribution kinetics of puerarin in rat hippocampus after acute local cerebral ischemia

Puerarin, isolated from the roots of Pueraria lobata, is widely used for treating cerebral ischemia in China. The time- and dose-dependent distribution characteristics of puerarin in the ischemic hippocampus are unknown. In this study, puerarin concentration was determined by an indirect competitive ELISA using anti-puerarin monoclonal antibody. Area under the curve (AUC0-120 min) of puerarin (80 mg/kg) in the embolic hippocampus was higher than that in the normal hippocampus; the increase was significant only at 40 and 20 mg/kg. The maximum concentration (Cmax) of puerarin in the embolic hippocampus was higher than that in the normal hippocampus at all doses. The increase in both AUC0-120 min and Cmax was dose-dependent. Time to reach the maximum concentration (Tmax) of puerarin in the embolic and normal hippocampus was similar. Although the mean residence time in the embolic hippocampus differed from that in the normal hippocampus at 40 and 80 mg/kg, it was higher in the embolic hippocampus than in the normal hippocampus at 20 mg/kg. This is the first study to report that the time- and dose-dependent distribution characteristics of puerarin in the normal and embolic hippocampus after middle cerebral artery occlusion in rats dictate puerarin dose and duration to treat stroke.

A general gas-assisted three-liquid-phase extraction method for separation and concentration of puerarin, 3'-methoxydaidzin, puerarinxyloside, daidzin and daidzein from puerariae extract.

In this work, a general and novel separation technique gas-assisted three-liquid-phase extraction was established and applied in separating and concentrating isoflavonoids from the actual sample of puerariae extract by one step. For the gas-assisted three-liquid-phase extraction method, optimal conditions were selected: polyethylene glycol 2000 and ethyl acetate as the flotation solvent, pH 5, (NH4 )2 SO4 concentration 350 g/L in aqueous phase, N2 flow rate 30 mL/min, flotation time 50 min, and flotation twice. Five isoflavonoids compounds puerarin, 3'-methoxydaidzin, puerarinxyloside, daidzin and daidzein were separated with recoveries of 82, 84, 80, 88 and 89%, respectively. The separated products were purified by preparative high-performance liquid chromatography, and the purity of the final products was >96%. The established general gas-assisted three-liquid-phase extraction was used to separate anthraquinones from Cassiae Semen under the optimal conditions, and the recoveries were >75%. The experimental results showed that the established gas-assisted three-liquid-phase extraction method is a general technique for separating active compounds from herb extract.

Attenuation of inflammatory pain by puerarin in animal model of inflammation through inhibition of pro-inflammatory mediators

In the current study, the puerarin was investigated for both acute Carrageenan and chronic CFA-induced inflammatory pain models. The Puerarin treatment significantly attenuated (P < 0.001) the mechanical hyperalgesia and mechanical allodynia in both Carrageenan and CFA-induced hyperalgesia. The Puerarin treatment also remarkably reduced (p < 0.001) the thermal hyperalgesic responses in both acute Carrageenan as well as chronic CFA-induced models. Furthermore, the Puerarin administration was also associated with significant inhibition of (p < 0.001) paw edema in both Carrageenan and CFA-induced models. The inflammatory mediators such as IL-1β, IL-6, TNF-α and vascular endothelial growth factor (VEGF) are significantly enhanced during inflammatory conditions, however, the Puerarin administration significantly altered (P < 0.001) the mRNA expression levels of these mediators. Additionally, the Puerarin treatment also significantly enhanced (P < 0.001) the mRNA expressions levels of the anti-oxidant enzymes such as Nrf2, HO-1 and SOD2. The Puerarin treatment is associated with significant (P < 0.001) inhibition of the acetic acid-induced Evans blue vascular permeability. Moreover, the concentration of Puerarin in various tissues was analyzed using High-performance liquid chromatography (HPLC) and the results showed that the Puerarin was significantly distributed towards the peripheral tissues such as liver and kidney and less distributed towards the brain.

Intestinal absorption of puerarin nanocrystalline self-stabilizing pickering emulsion in rats

To study the intestinal absorption characteristics of drug's nanocrystalline self-stabilizing Pickering emulsion (NSSPE) in situ in rats. Rat single-pass intestinal perfusion model was established, and high performance liquid chromatography (HPLC) was used to detect the concentration of puerarin in rat intestinal perfusion solution, assay the absorption rate constant (Ka) and the intestinal apparent permeability coefficient (Papp) of NSSPE in duodenum, jejunum, ileum, and colon, which were compared with those of raw material, nanocrystal and normal emulsion, respectively. For NSSPE, the Ka and Papp values were in the following order: duodenum>jejunum>ileum (P<0.05)>colon (P<0.01). However, there was no obvious difference between jejunum and ileum. As compared with raw material, nanocrystal and normal emulsion, the Ka and Papp values of NSSPE in duodenum were significantly higher than those of other three preparations (P<0.05); and the Ka and Papp values of NSSPE in jejunum and colon were significantly higher than those of raw material, nanocrystal and normal emulsion (P<0.01); and the Ka and Papp of NSSPE in ileum were also higher than those of raw material and normal emulsion (P<0.05), but had no obvious difference with nanocrystal. The results showed that NSSPE could significantly improve the absorption of puerarin in the intestine of rats.

Effects of glycyrrhizin on the pharmacokinetics of puerarin in rats

1. Puerarin has been reported to possess a wide range of pharmacological activities. This study investigated the effects of glycyrrhizin on the pharmacokinetics of puerarin in rats.2. The pharmacokinetics of orally administered puerarin (50 mg/kg) with or without glycyrrhizin pretreatment (100 mg/kg/day for 7 days) were investigated. The plasma concentration of puerarin was determined using a sensitive and reliable LC-MS/MS method. The pharmacokinetics profiles were calculated and compared. Additionally, a Caco-2 cell transwell model was used to investigate the potential mechanism of glycyrrhizin’s effects on the pharmacokinetics of puerarin.3. The results showed that when the rats were pretreated with glycyrrhizin, the maximum concentration (Cmax) of puerarin decreased from 761.25 ± 52.34 to 456.32 ± 34.75 ng/mL, and the area under the concentration–time curve from zero to infinity (AUC0–inf) also decreased from 4142.15 ± 558.51 to 2503.74 ± 447.57 μg·h/L. The oral clearance of puerarin increased significantly from 12.20 ± 1.53 to 20.47 ± 3.25 L/h/kg (p < 0.05). The Caco-2 cell transwell experiments indicated that glycyrrhizin could increase the efflux ratio of puerarin from 1.88 to 3.14.4. In conclusion, these results indicated that glycyrrhizin could affect the pharmacokinetics of puerarin, possibly by decreasing the systemic exposure of puerarin by inducing the activity of P-gp.

Stability optimization of puerarin nanocrystalline self-stabilizied Pickering emulsion by response surface methodology

A new Pickering emulsion, puerarin nanocrystalline self-stabilized Pickering emulsion (Pu-NSSPE) was developed. Box-Behnken design was used for optimizing the preparation formulation of Pu-NSSPE to improve its stability, and the effects of concentration of puerarin, volume ratio of water to oil, and pH value of water phase on the stratification index of emulsion, droplet size and drug concentration in emulsion were investigated. Results showed that the optimized Pu-NSSPE could be prepared with the concentration of puerarin of 0.5%, the volume ratio of water to oil of 9∶1 and the pH of water of 9. The size of emulsion droplet of optimized Pu-NSSPE was (12.70±1.17) μm and the drug content was (4.49±0.21) g•L⁻¹. The above indexes had no significant changes within the storage of 6 months at room temperature, indicating good stability. Microstructure characterizations by scanning electron micrograph, confocal laser scanning microscope and fluorescence microscope showed that the optimized Pu-NSSPE had a stable core-shell structure of emulsion droplet formed by the adsorption of puerarin nanocrystallines at the surface of oil droplets, which may be the microstructure reason for the long stability of Pu-NSSPE.

Effect of compound Longmaining decoction with different combinations on intestinal absorption of puerarin

To study the effects of compound Longmaining(FFLMN) with different combinations on the intestinal absorption of puerarin. The rat single pass intestinal perfusion model was adopted, and the concentration of puerarin in intestinal samples was determined by HPLC. The effects of different combination groups on the absorption of puerarin in duodenum, jejunum, ileum and colon were investigated. The combined drugs were GG(Puerariae Lobatae Radix), GG-CSL (Puerariae Lobatae Radix compared with Dioscoreae Nipponicae Rhizoma), GG-CX(Puerariae Lobatae Radix compared with Chuanxiong Rhizoma) and FFLMN (compound Longmaining). We found that the absorption rate constant(Ka) and the apparent coefficient(Papp) of puerarin had no significant difference between GG-CSL and FFLMN groups, but significantly higher in GG and GG-CX groups(P<0.05) in the duodenum and ileum. In jejunum and colon, Ka and Papp of puerarin showed significant differences between GG and other groups(P<0.05). At the same time, FFLMN also had significant differences with GG-CSL and GG-CX groups(P<0.05). The results showed that in the whole intestine of rats, FFLMN could significantly promote the absorption of puerarin. In the duodenum and ileum, Dioscoreae Nipponicae Rhizoma played a significant role in promoting absorption of puerarin. In jejunum and colon, Dioscoreae Nipponicae Rhizoma and Chuanxiong Rhizoma have a synergistic effect in promoting absorption of puerarin.

Modified β -CD-Cu ion complex and yam mucilage assisted batch foam fractionation for separating puerarin from Ge-gen ( Radix puerariae )

Abstract At present, the large scale application of batch foam fractionation is still in confrontation with many problems and difficulties, especially for the enrichment of non-surface-active materials. It is difficult to select a suitable surfactant as the collector when a non-surface-active material can only form a stable association with the expensive surfactants or has not any interactions with the commercially available surfactants. The objective of this work was to investigate the feasibility of batch foam fractionation for recovering such a non-surface-active material, puerarin. Yam mucilage, an abundant byproduct from the manufacture of yam starch, was used to generate a stable foam phase based on its good foamability. According to the properties of puerarin and yam mucilage, β -cyclodextrin ( β -CD) was selected as a basic material to establish an association between them. The results of fluorescence sensitization experiments indicated that puerarin could form an equimolar inclusion complex with β -CD and the inclusion constant was 405.8. Subsequently, β -CD was modified by introducing carbon disulfide and copper (Cu) ion. Then, puerarin could be adsorbed on the gas-liquid interface in the form of ternary complex with modified β -CD-Cu ion complex and glycoprotein molecules (see Fig. 7). Batch foam fractionation was carried out by using the crude extracting solution as the initial feeding solution, in which the concentration of puerarin was as high as 4.6 g/L. Under the suitable conditions of temperature 50 °C, pH 6.0, loading volume of feed solution 400 mL, the pore diameter of gas distributor 0.450 mm, additive volume of yam mucilage 30 mL and volumetric air flow rate 100 mL/min, the enrichment ratio and the percent recovery of puerarin were 4.3 and 82.3%, respectively. This strategy could be generalized to the separation of various non-surface-active materials due to the low cost and the diversiform cavity dimension of cyclodextrins.

Influence of puerarin on proliferative activity of human fetal scleral fibroblasts and expression of collagen type I and matrix metalloproteinase-2 in power frequency electromagnetic field

To investigate the influence of puerarin on the proliferative activity of human fetal scleral fibroblasts (HFSFs) and the expression of collagen type I and matrix metalloproteinase-2 (MMP-2) in HFSFs in the power frequency electromagnetic field. HFSFs were cultured and divided into four radiation groups (0.2 mT, 50 Hz) and control group. Puerarin at concentrations of 0.0, 1.0, 5.0, and 10.0 μmol/L was added to the four radiation groups, respectively. The methyl thiazolyl tetrazolium colorimetry was used to measure the influence on the proliferative activity of HFSFs, Western blot and RT-qPCR were used to measure the protein and mRNA expression of collagen type I and MMP-2 induced by puerarin in the power frequency electromagnetic field. The radiation groups and control group showed significant increases in the proliferative activity of HFSFs over the culture time (F= 959.472 and 279.468, both P<0.01). At 24 and 48 hours, the radiation groups showed significantly lower proliferative activity than the control group (0.432±0.038/0.591±0.017 vs 0.536±0.034/0.801±0.020, both P<0.01). With the increasing concentration of puerarin (0.0, 1.0, 5.0, and 10.0 μmol/L) , the proliferative activity of HFSFs significantly increased, with A values of 0.598±0.031, 0.809±0.041, 0.910±0.037, and 0.983±0.054, respectively (P<0.05). After exposure for 24 hours, the radiation groups showed significantly lower protein expression of collagen type I and significantly higher protein expression of MMP-2 (t=7.917 and 7.831, both P<0.01) ; compared with the 0.0 μmol/L puerarin group, the 1.0, 5.0, and 10.0 μmol/L puerarin groups showed significant increases in the protein expression of collagen type I and significant reductions in the protein expression of MMP-2 (all P<0.01). Compared with the control group, the radiation groups showed significant reductions in the mRNA expression of collagen type I and MMP-2 (t=17.293 and 16.378, both P<0.01) ; compared with the 0.0 μmol/L puerarin group, the 1.0, 5.0, and 10.0 μmol/L puerarin groups showed significant increases in the mRNA expression of collagen type I and significant reductions in the mRNA expression of MMP-2 (P<0.01). Puerarin can inhibit the reduction in the proliferative activity of HFSFs in the power frequency electromagnetic field, upregulate the expression of collagen type I, downregulate the expression of MMP-2, and thus exert its protective effect.

Promotive effect of puerarin on melanogenesis in melanocytes and its possible mechanisms

Objective To evaluate the effect of puerarin on melanogenesis in melanocytes, and to explore its possible mechanisms. Methods Third-to fifthpassage melanocytes isolated from human foreskin were treated with different concentrations (1, 5, 10, 20, 40, 80 and 160 μmol/L)of puerarin for 24 hours, with those receiving no treatment as the normal control group. Methyl thiazolyl tetrazolium (MTT)assay was performed to evaluate the proliferative activity of melanocytes, a sodium hydroxide solubilization method was used to measure melanin content, and reverse transcription PCR (RT-PCR)and Western blot analysis were performed to quantify the mRNA and protein expressions of microphthalmiaassociated transcription factor (MITF), tyrosinase (TYR)and tyrosinaserelated protein-1 (TRP-1) respectively. Results There were no significant differences in the proliferative activity of melanocytes between the puerarin (1-40 μmol/L)groups and normal control group (P > 0.05), and 40 μmol/L was chosen as the concentration of puerarin for subsequent experiments. Compared with the normal control group, the 40-μmol/L puerarin group showed increased melanin content as well as mRNA and protein expressions of MITF, TYR and TRP-1 (all P < 0.05). Concretely speaking, the protein expressions of MITF, TYR and TRP-1 in the 40-μmol/L puerarin group were increased by 8.69%, 10.28% and 10.58% compared with the normal control group respectively (all P < 0.05), and their mRNA expressions were 2.48, 1.91 and 1.63 times higher in the 40-μmol/L puerarin group than in the normal control group respectively (all P < 0.05). Conclusion Puerarin can increase the mRNA and protein expressions of MITF, TYR and TRP-1, and promote melanogenesis in melanocytes. Key words: Vitiligo; Melanocytes; Puerarin; Cell proliferation; Microphthalmia-associated transcription factor; Monophenol monooxygenase

Effect of puerarin in Longmaining formula on pharmacokinetics-pharmacodynamics correlation in rats with myocardial ischemia

To study the pharmacokinetics of puerarin in compound Longmaining(FFLMN) in normal rats and myocardial ischemia rats, and investigate its correlation with anti-myocardial ischemia effect of FFLMN. Models of myocardial ischemia rats were produced by subcutaneous injection of isoproterenol(ISO), then FFLMN extract solution was administered by gavage. Orbital sinus blood sampling was collected at different time points after gavage. HPLC-UV method was applied to determine the concentration of puerarin in plasma, and compare the difference in pharmacokinetics between normal rats and model rats after application of same dose of FFLMN. Meanwhile, microplate reader was used to determine IL-6 and SOD activities in plasma of different time points, and draw dose-effect curve. The results indicated that the pharmacokinetics of puerarin conformed to the two-compartment model in both normal group and myocardial ischemia model group. In the comparison of main pharmacokinetic parameters between two groups: AUC0-∞=(11.451±3.228) mg•h•L⁻¹,AUC0-t=(14.047±3.765) mg•h•L⁻¹, Cmax=(5.623±1.40) mg•L⁻¹ in normal group; AUC0-∞=(68.849±50.396 9) mg•h•L⁻¹, AUC0-t= (58.312±45.802) mg•h•L⁻¹,Cmax=(18.456±7.517) mg•L⁻¹ in treatment group. The SOD level was significantly increased and IL-6 concentration was significantly decreased in plasma, indicating that as compared with the normal group, puerarin in FFLMN had a higher plasma concentration, slower elimination rate and higher bioavailability. Therefore, puerarin concentration in plasma has correlation with the anti-myocardial ischemia effect of FFLMN, which could increase SOD level and inhibit the release of IL-6.

Enhanced Accuracy of Near-Infrared Spectroscopy for Traditional Chinese Medicine with Competitive Adaptive Reweighted Sampling

ABSTRACTThe accuracy of near-infrared quantitative models for traditional Chinese medicine is restricted by the matrix, low-concentration markers, and overlapping spectral bands. Competitive adaptive reweighted sampling, a recently developed algorithm, selects an optimal combination of multicomponent spectral data. In this article, the performance of this method was evaluated through the analysis of traditional Chinese medicine. The near-infrared spectra of the pharmaceutics were obtained and the concentration of puerarin was determined. After optimization of spectral pretreatment methods, competitive adaptive reweighted sampling was performed in each dataset to select key wavenumbers. Sixty-eight, thirty, and eight variables were selected for the raw material, intermediate product, and final product, respectively. Partial least squares models were constructed based on the selected variables. Enhanced accuracy was obtained using the competitive adaptive reweighted sampling-coupled models. The results indicated that competitive adaptive reweighted sampling improved the accuracy and simplified calibration while offering a new approach for the rapid and nondestructive analysis of traditional Chinese medicine.

Optimization of Ultrasound-Assisted Acid Hydrolysis of Total Isoflavones in Radix puerariae Using Response Surface Methodology

The present study reports on ultrasound-assisted hydrolysis of total isoflavones in Radix puerariae using hydrochloric acid as catalyst and the influence of different hydrolysis parameters on the yield of puerarin. Based on the single factor test, response surface methodology (RSM, Box–Behnken Design) was used to develop predictive models for simulation and optimization of the hydrolysis conditions in order to increase the yield of puerarin. The optimum hydrolysis conditions were as follows: hydrolysis time of 48 min, hydrolysis temperature of 78°C, ultrasonic power of 180 W and the concentration of hydrochloric acid of 4.6% (v/v). Under these optimal conditions, the concentration of puerarin was increased to 15.92%, which is 19.5% higher than that in the original crude extract. At the same time, compared with the traditional acid hydrolysis, the time needed in ultrasound-assisted hydrolysis is only 45 min, which is 120 min shorter than traditional hydrolysis.