Oral Puerarin Research Articles

Puerarin ameliorates skeletal muscle wasting and fiber type transformation in STZ-induced type 1 diabetic rats

Puerarin is an isoflavonoid extracted from Pueraria lobate with extensive pharmacological effects in traditional Chinese medicine. The evidence implicates that puerarin mitigates hyperglycemia and various relevant complications. Here, the effect of puerarin on skeletal muscle wasting induced by type 1 diabetes (T1D) was explored. Streptozotocin (STZ)-induced T1D male Sprague Dawley (SD) rats were used in this study. Muscle strength, weight and size were measured. L6 rat skeletal muscle cells were applied for in vitro study. Our results showed that eight-week oral puerarin administration (100 mg/kg) increased muscle strengths and weights accompanied by enhanced skeletal muscle cross-sectional areas in diabetic rats. Simultaneously, puerarin also reduced expressions of several muscle wasting marker genes including F-box only protein 32 (Atrogin-1) and muscle-specific RING-finger 1 (Murf-1) in diabetic group both in vitro and in vivo. Transformation from type I fibers (slow muscle) to type II fibers (fast muscle) were also observed under puerarin administration in diabetic rats. Puerarin promoted Akt/mTOR while inhibited LC3/p62 signaling pathway in skeletal muscle cells. In conclusion, our study showed that puerarin mitigated skeletal muscle wasting in T1D rats and closely related with Akt/mTOR activation and autophagy inhibition. Whether this effect in murine applies to humans remains to be determined.

Comparative study of oral and intranasal puerarin for prevention of brain injury induced by acute high-altitude hypoxia.

Human activities in the areas of high altitude have increased significantly recently. Brain is highly sensitive to changing of oxygen pressure due to high altitude, and this physiological response may lead to serious brain injury, such as learning and memory disabilities. Puerarin is a phytoestrogen with many pharmacological activities, such as treatment of neurological disorders. However, most of current drugs can not easily enter brain through the blood-brain barrier (BBB). The nose-to-brain route can bypass BBB for brain-targeting. Here, thermosensitive in situ hydrogels (TISGs) of puerarin were prepared with poloxamers 407, poloxamers 188 and propylene glycol to improve bioavailability and brain targeting. In vitro drug release in simulated nasal fluids, rheological properties and cilia toxicity of puerarin TISGs were explored. The pharmacodynamics and pharmacokinetics of puerarin by intranasal (i.n.) and oral (p.o.) administrations were also evaluated. The viscosity of puerarin TISGs tended to increase obviously with increased temperature. The puerarin release profile and transmucosal process of puerarin TISGs could be described with the first-order kinetics equation, depending on drug diffusion. The cilia toxicity of puerarin TISGs was not obvious. Rat models of hypobarism/hypoxia-induced brain injury were established with a hypobaric simulation chamber. Morris water maze and open filed tests indicated that puerarin TISGs improved the spatial memory and spontaneous exploratory behavior of the rats suffering from hypoxia-induced brain injury. Furthermore, puerarin TISGs decreased the level of oxidative stress cytokines (malondialdehyde (MDA) and glutathione (GSH)) in the peripheral circulation, alleviated the cerebral histological lesions, and relieved the expression of hypoxia-inducible factor-1α (HIF-1α). Intranasal puerarin TISGs were absorbed quickly with a shorter Tmax (10.0±5.7min) compared to that of oral puerarin (36±13.4min). In addition, the relative bioavailability of i.n. puerarin TISGs was high to 300% compared to oral administration of puerarin. The area under the curve (AUC) of brain after i.n. administration of puerarin TISGs was 954.5±335.1h.ng/mL, while no puerarin was detected in the brain after oral administration. Therefore, i.n. puerarin TISGs led to excellent brain targeting effect. Puerarin TISGs are an effective neuroprotector formulation for prevention of brain injury induced by acute high-altitude hypoxia.

Pharmaceutics research advances in oral administration of puerarin

Puerarin is a naturally occurring isoflavone C-glycoside,isolated from the root of Pueraria lobata,which has attracted extensive attention in the medical circles because of its various pharmacological effects,such as vasodilation,cardioprotection,neuroprotection,antioxidant,anticancer,anti-inflammation,alleviating pain,promoting bone formation,inhibiting alcohol intake,and attenuating insulin resistance. However,its low oral bioavailability has limited its clinical application. This review gives a comprehensive summary of the researches on physicochemical properties,pharmacokinetics( absorption,distribution,metabolism and excretion,pharmacokinetic parameters) in oral administration,and pharmaceutics research strategies of puerarin in recent years,and the in vivo behavior difference between multicomponent and single component environment was also summarized. The reasons( low water solubility,poor membrane permeability,short half-life,inhibition of P-gp efflux and first-pass metabolic effects of intestinal enzymes,etc.) for low bioavailability were concluded and the idea that multicomponent enviroment would affect the bioavailability was clarified. The aim of this review is to provide literature basis for the development of new dosage forms and new technologies for multivariate compound drug delivery system to improve the bioavailability of oral puerarin,and to propose ways to improve the bioavailability of BCS Ⅳ drugs derived from traditional Chinese medicine by fully enlarging the synergistic effect of multi-components or reasonably using the inhibitory effect between components.

Puerarin protects rat liver and kidney against cadmium-induced oxidative stress

Oxidative stress is thought to be involved in cadmium (Cd) induced toxicity. This study examined the possible protective effect of puerarin on cadmium chloride (CdCl2, 2 mg/kg b.w.) induced toxicity in male rats. Male SD rats were treated with either intraperitoneal Cd and/or oral puerarin (100 mg/kg. b.w.) for 4 weeks. The results demonstrated that exposure to Cd led to an increase in the level of BUN, ALT and AST in serum. Cadmium raised the concentrations of MDA and GSH, and decreased antioxidants activities (SOD, CAT, and GSH-Px) in the liver and kidney. Conversely, administration of puerarin markedly attenuated Cd-induced biochemical alterations in serum, liver, and kidney tissues. These results suggest that puerarin exerts protective effects against Cd toxicity attributable to its antioxidant actions.

The effect of oral puerarin administration on wound healing in diabetic rat model

The effect of oral puerarin administration on wound healing in diabetic rat model

Puerarin offsets the anticoagulation effect of warfarin in rats by inducing rCyps, upregulating vitamin K epoxide reductase and inhibiting thrombomodulin.

The current study was conducted to investigate the potential pharmacokinetic and pharmacodynamic interactions between warfarin and puerarin which is the most abundant component in Pueraria lobata (Gegen). In vivo and ex vivo rat models were used to reveal the underlying mechanisms of such interactions. Apart from one control group, five groups of Sprague-Dawley rats were treated with warfarin, oral puerarin, oral puerarin with warfarin, intravenous puerarin, intravenous puerarin with warfarin. The treatment lasted for 5 consecutive days. Thereafter, the levels of warfarin, warfarin metabolites and puerarin in plasma of these rats were monitored and compared. The rCyps activity and expression in rat livers of different treatment groups were assessed. The prothrombin time was observed. The vitamin K epoxide reductase (VKOR) activity and expression in rat livers were evaluated. Thrombomodulin activity and expression in the rat lung and rat plasma were assessed. The soluble thrombomodulin (sTM) concentrations of different treatment groups were examined. Intravenously administered puerarin altered the pharmacokinetics of warfarin significantly by shortening t1/2 , decreasing AUC0-96 h and increasing the clearance of warfarin. Further mechanistic studies suggested that both oral and intravenous administration of puerarin significantly induced the activities and expressions of rCyp2b1, rCyp2c6 and rCyp1a1. In addition, co-administration of puerarin reduced the prothrombin time of rat plasma by enhancing VKOR and inhibiting thrombomodulin. Puerarin increased warfarin metabolism and offset warfarin anticoagulation by inducing rCyps, upregulating VKOR and inhibiting thrombomodulin in rats. The clinical impact of such potential interactions warrants further verification. Copyright © 2016 John Wiley & Sons, Ltd.

Preparation, characterization and bioavailability of oral puerarin nanoparticles by emulsion solvent evaporation method

In this paper, puerarin (PUE) was nanocrystallized by emulsion solvent evaporation (ESE) method, followed by freeze-drying. The solubility, dissolution rate and oral bioavailability of PUENs were significantly improved compared with raw PUE.

White pepper and piperine have different effects on pharmacokinetics of puerarin in rats.

This study attempted to explore the effects of white pepper and its major component piperine on puerarin administered to rats. Pharmacokinetic parameters of puerarin in rats were determined by oral administration (400 mg/kg) or intravenous injection (40 mg/kg) of puerarin, pretreated with or without white pepper and piperine given orally. Compared to the control group given oral puerarin only, the combined use of piperine (10 or 20 mg/kg) increased the C max of puerarin by 1.30-fold or 1.64-fold and the AUC0–∞ by 133% or 157%, respectively. In contrast, coadministration of white pepper (125 or 250 mg/kg) decreased oral absorption of puerarin to 83% or 74%, respectively. On the other hand, pretreatment with piperine orally did not alter the intravenous pharmacokinetics of puerarin, while the AUC of puerarin after intravenous administration was increased by pretreatment with white pepper. The results indicate that pretreatment with piperine or pepper exerts different effects on pharmacokinetics of puerarin administrated via intragastric and intravenous routes. Therefore, it is suggested that the combined application of piperine or white pepper with puerarin should be carefully monitored for potential diet-drug interactions.

Lymphatic transport of puerarin occurs after oral administration of different lipid-based formulations to unconscious lymph duct-cannulated rats

This study investigated the potential of targeted intestinal lymphatic transport of puerarin via a lipid formulation approach. Three formulations of PEG nanoemulsion, nanosuspension and an oil suspension containing puerarin were examined with the lymph-cannulated anaesthetized rat model. Plasma and lymph samples were analyzed by HPLC. Lymph triglyceride was measured using an enzymatic colorimetric technique. After 8 h, the total administered dose accumulated in the thoracic lymph duct was analyze. Nanoemulsion, nanosuspension and oil suspension was 0.065 ± 0.006%, 0.137 ± 0.018%, 0.021 ± 0.002% of the administered dose, respectively. In nanoemulsion, nanosuspension and oil suspension group, the systemic bioavailability of oral puerarin was 11%, 16% and 11% for lymph-cannulated rats, 41%, 67% and 18% for control rats. Absorption into the intestinal lymph should thus contribute to ∼30%, 51% and 7% of the systemic bioavailable puerarin. This data indicated that lipid-based nano drug formulation produced higher lymph concentrations of puerarin than oil suspension. The nanosuspension formulation may be considerable in terms of increased local concentrations in lymphoid tissue.

Examination of lymphatic transport of puerarin in unconscious lymph duct-cannulated rats after administration in microemulsion drug delivery systems

The potential for microemulsion drug delivery systems to improve the lymphatic transport and the portal absorption of a poorly water-soluble drug, puerarin, were investigated in lymph-cannulated rats. SD rats were operated for lymph duct cannulation and were orally dosed with 3 ml puerarin microemulsion (0.6 mg/g, n = 6). The lymph and plasma were collected over 8 h and the concentrations of puerarin and triglyceride were measured. Similarly, control rats (non-lymph-cannulated, n = 6) were dosed orally with puerarin microemulsion and subsequently with puerarin injection intravenously. Plasma and lymph samples were analysed by HPLC. Lymph triglyceride was measured using an enzymatic colorimetric technique. The extent of lymphatic transport via the thoracic duct was 0.06% of the dose for the animals dosed with puerarin microemulsion. The systemic bioavailability of oral puerarin co-administered with lipid was only 16% in the lymph duct-cannulated rats compared with 40% in the controls. These data clearly indicate that the lymphatic transport process contributes significantly to intestinal absorption of puerarin and subsequently to its systemic bioavailability. The results imply that the pharmaceutical scientist may use microemulsion formulations to optimize lymph-targeting drug delivery systems, by improving the extent of lymphatic transport.