In vitro and in vivo anticancer activity of a novel puerarin nanosuspension against colon cancer, with high efficacy and low toxicity

Targeted lung cancer therapy: preparation and optimization of transferrin-decorated nanostructured lipid carriers as novel nanomedicine for co-delivery of anticancer drugs and DNA

Purpose

Nanostructured lipid carriers (NLC) represent an improved generation of lipid nanoparticles. They have specific nanostructures to accommodate drugs/genes, and thus achieve higher loading capacity. The aim of this study was to develop transferrin (Tf)-decorated NLC as multifunctional nanomedicine for co-delivery of paclitaxel (PTX) and enhanced green fluorescence protein plasmid.

Methods

Firstly, Tf-conjugated ligands were synthesized. Secondly, PTX- and DNA-loaded NLC (PTX-DNA-NLC) was prepared. Finally, Tf-containing ligands were used for the surface decoration of NLC. Their average size, zeta potential, drug, and gene loading were evaluated. Human non-small cell lung carcinoma cell line (NCl-H460 cells) was used for the testing of in vitro transfection efficiency, and in vivo transfection efficiency of NLC was evaluated on mice bearing NCl-H460 cells.

Results

Tf-decorated PTX and DNA co-encapsulated NLC (Tf-PTX-DNA-NLC) were nano-sized particles with positive zeta potential. Tf-PTX-DNA-NLC displayed low cytotoxicity, high gene transfection efficiency, and enhanced antitumor activity in vitro and in vivo.

Conclusion

The results demonstrated that Tf-PTX-DNA-NLC can achieve impressive antitumor activity and gene transfection efficiency. Tf decoration also enhanced the active targeting ability of the carriers to NCl-H460 cells. The novel drug and gene delivery system offers a promising strategy for the treatment of lung cancer.

Macroporous adsorbent resin-based wheat bran polyphenol extracts inhibition effects on H2O2-induced oxidative damage in HEK293 cells

In the present study, polyphenol-rich extracts of wheat bran (PEWB) were prepared via adsorption on macroporous resins and desorption with ethanol.

Synergistic antitumor effect of puerarin combined with 5-fluorouracil on gastric carcinoma

Combination chemotherapy is a crucial method in the treatment of gastric cancer. The aim of the present study was to investigate the inhibitory effects of puerarin and 5‑fluorouracil (5‑FU) on BGC‑823 gastric cancer cells in vitro and in vivo. The in vitro growth inhibition of puerarin or 5‑FU alone or combined on BGC‑823 cells was determined using a cell counting kit 8 (CCK‑8) on living cells. Apoptotic morphological features and proteins expression levels were detected by Hoechst 33258 staining, an Annexin V/propidium iodide apoptosis kit and western blot analysis, respectively. Tumor xenografts were established in nude mice and the inhibitory effects and side effects were detected. Results of the CCK‑8, Hoechst 33258 staining and flow cytometry revealed that the combined treatment was more effective than the separate treatments. The tumor volume was 90.65% of that of the controls and the mean tumor weight was only 0.125 g at the end of the experiment in the combination group compared with the control group (0.822 g). In addition, it was determined that liver and renal toxicity did not increase in combined treatment. These findings showed that puerarin and 5‑FU produced a significant synergic effect on gastric cancer cells, while there was no increase in side effects.

Synergistic effects of puerarin combined with 5-fluorouracil on esophageal cancer

Puerarin is an isoflavone derived from kudzu roots with a wide range of biological and medicinal properties. The aim of the present study was to investigate the inhibitive effects of puerarin combined with 5‑fluorouracil (5‑FU) on Eca‑109 esophageal cancer cells in vitro and in vivo. Inhibitive effects of the treatments on Eca‑109 cells were detected by cell counting kit‑8, Hoechst 33258 staining and flow cytometry. A tumor xenograft model was established in nude mice. Puerarin and 5‑FU, administered either in combination or individually, were injected into mice and the inhibitive effects along with any side effects were observed. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Puerarin and 5‑FU, administered as combined treatment or individual drugs, significantly inhibited proliferation and induced marked apoptosis. The mean growth inhibition rate (± standard deviation) reached 87.27±5.37% and the apoptotic rate at 48 h reached 36.18±1.24% in the combined treatment group. The percentages of apoptotic cells induced by puerarin and 5‑FU (combined or alone) were significantly higher than those of the control group (P<0.05). Puerarin or 5‑FU alone significantly inhibited the growth of xenograft tumors in comparison to the control group (P<0.05), with inhibition rates of 76.93 and 72.21%, respectively. The drugs combined exhibited a significantly greater effect than either drug alone (P<0.05), with the tumor inhibition rate reaching 89.06%. During the course of chemotherapy, no evident side effects were observed. The results suggested that the combined inhibitive effects of puerarin and 5‑FU were greater than the effects of the agents used individually. In addition, puerarin combined with 5‑FU exhibited synergistic effects at lower concentrations and promoted apoptosis, but did not increase the side effects of chemotherapy, which indicated that puerarin may be a safe and effective chemosensitive agent in the treatment of human esophageal cancer.

Puerarin inhibits growth and induces apoptosis in SMMC-7721 hepatocellular carcinoma cells

Puerarin, a predominant isoflavonoid compound extracted from the Chinese medicinal herb Radix Puerariae, is considered to exhibit an antitumor effect. In the present study, the effects of puerarin on SMMC-7721 human hepatocellular carcinoma cells were investigated. Cell viability was assessed by MTT assay. Apoptosis was detected by flow cytometry with Annexin V-fluorescein isothiocyante staining and morphological observation of nuclear changes by Hoechst staining. The mitochondrial membrane potential (MMP) was monitored using rhodamine 123. The generation of reactive oxygen species (ROS) was quantified using dichloro‑dihydro‑fluorescein diacetate. Polymerase chain reaction and western blot analysis were used to detect the expression levels of apoptosis‑associated genes. The results revealed that high concentrations of puerarin (500, 1,000 and 1,500 µg/ml) significantly inhibited the proliferation of SMMC-7721 cells in a time- and dose-dependent manner. Simultaneously, apoptotic rates were increased and cell morphology was changed following puerarin treatment. Furthermore, puerarin‑induced apoptosis of SMMC-7721 cells was associated with loss of MMP and generation of ROS. Puerarin treatment increased caspase‑3,8,9 and apoptosis‑inducing factor (AIF) mRNA expression levels in SMMC‑7721 cells, while the phosphorylation levels of P38, extracellular signal‑regulated kinase (ERK1) and c-Jun N‑terminal kinase were also increased. Furthermore, caspase-9 and AIF protein expression was upregulated. In conclusion, puerarin inhibited proliferation and induced apoptosis in SMMC‑7721 cells via the mitochondria‑dependent pathway; however, the specific mechanisms require further investigation.

Enhanced oral absorption and therapeutic effect of acetylpuerarin based on D-α-tocopheryl polyethylene glycol 1000 succinate nanoemulsions

Background

Acetylpuerarin (AP), because of its lower water solubility, shows poor absorption that hinders its therapeutic application. Thus, the aim of this study was to prepare nanoemulsions for AP, enhance its oral bioavailability, and thus improve the therapeutic effect.

Methods

The nanoemulsions stabilized by D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) were prepared by high-pressure homogenization and characterized in terms of particle size, drug loading, morphology, and in vitro drug release. A lipid digestion model was used to predict in vivo drug solubilization in the gastrointestinal environment. The pharmacokinetics of AP formulations were performed in rats; meanwhile, a chylomicron flow-blocking rat model was used to evaluate the lymphatic drug transport. Moreover, the therapeutic effects of AP nanoemulsions on the model of focal cerebral ischemia-reperfusion for brain injury were also assessed.

Results

The nanoemulsions with a droplet size of 150 nm were well stabilized by TPGS and showed a high loading capacity for AP. In the digestion model, the distribution of AP in aqueous phase/pellet phase was about 90%/10% for nanoemulsions and 5%/95% for oil solution, indicating that the drug encapsulated in nanoemulsions would present in solubilized form after transportation into the gastrointestinal tract, whereas drug precipitation would occur as the oil solution was orally administered. The area under the curve value of AP nanoemulsions was 5.76±0.56 μg·hour·mL⁻¹, or was about 2.6 and 1.7 times as great as that of suspension and oil solution, respectively, indicating enhanced drug absorption and thus achieving a better neuroprotection effect on cerebral ischemic reperfusion injury. The values of peak plasma concentration and area under the curve from the blocking model were significantly less than those of the control model, suggesting that the lymphatic transport performed a very important role in absorption enhancement.

Conclusion

Enhanced oral bioavailability in nanoemulsions was achieved via the mechanism of the maintenance of drug solubilization in the gastrointestinal tract and the enhancement of lymphatic transport, which resulted in therapeutic improvement of cerebral ischemic reperfusion injury.

Engineered nanocrystal technology: in-vivo fate, targeting and applications in drug delivery

Formulation of nanocrystals is a robust approach which can improve delivery of poorly water soluble drugs, a challenge pharmaceutical industry has been facing since long. Large scale production of nanocrystals is done by techniques like precipitation, media milling and, high pressure homogenization. Application of appropriate stabilizers along with drying accords long term stability and commercial viability to nanocrystals. These can be administered through oral, parenteral, pulmonary, dermal and ocular routes showing their high therapeutic applicability. They serve to target drug molecules in specific regions through size manipulation and surface modification. This review dwells upon the in-vivo fate and varying applications in addition to the facets of drug nanocrystals stated above.

Effects of particle size on the pharmacokinetics of puerarin nanocrystals and microcrystals after oral administration to rat

Puerarin, which is extracted from traditional Chinese medicine, is widely used in clinic in China and mainly used as a therapeutic agent to cardiovascular diseases. Owing to its poor water solubility and adverse drug reactions caused by cosolvents after intravenous administration, the development of oral formulation is urgently needed. Nowadays, nanocrystals technique has become a preferred way to develop oral dosage form. In this study, we used high pressure homogenization (HPH) to prepare puerarin nanocrystals and microcrystals with different sizes ranged from 525.8 nm to 1875.6 nm and investigated the influence of particle size on pharmacokinetics. The nanocrystals and microcrystals prepared were characterized using DLS, DSC, XRD and SEM, and we found that the crystalline state of puerarin was changed during the preparation process and the drug was dispersed into HPMC. In the pharmacokinetic study, we observed an increasing of Cmax and AUC and a decreasing of CL/F with the decreasing of particle size. The AUC of the puerarin nanocrystals (525.8 nm) was 7.6-fold of that of raw puerarin suspension, with an absolute bioavailability of 21.44%. From the above results, we can conclude that nanocrystal technique is an efficient technology to improve the oral bioavailability of puerarin.

Stability of nanosuspensions in drug delivery

Nanosuspensions are nanosized colloidal dispersion systems that are stabilized by surfactants and/or polymers. Because nanosizing results in the creation of new interfaces and in a positive Gibbs free energy change, nanosuspensions are thermodynamically unstable systems with a tendency toward agglomeration or crystal growth. Despite extensive research on nanosuspension technology, stability remains a limitation for pharmaceutical or industrial applications of nanosuspensions. Furthermore, the empirical relationship between stabilizer efficacy and nanosuspension stability has not been well characterized. This review focuses on the issue of nanosuspension stability in drug delivery to present the state of the art of nanosuspensions. Therefore, this review will discuss unstable suspensions, methods and guidelines for selecting and optimizing stabilizers, approaches for enhancing stability, and other factors that influence nanosuspension stability. This review could serve as a reference for the educated selection of a stabilizer for a specific drug candidate and the optimization of the operational parameters for nanosuspension formulation, rather than the currently practiced trial-and-error approach.