Zhi-ping Wang

O-acylation of chitosan nanofibers by short-chain and long-chain fatty acids

Chitosan nanofibers (CSNFs) have potential applications in biomaterials, oil recovery and food packaging, but their instability in moist environment has limited their full utilization. Here we report that CSNFs can be O-acylated in a post-electrospinning treatment by using pyridine as catalyst and short-chain (C2, C3, C4, C5 and C6) and long-chain (C8 and C12) fatty acid anhydrates as acylation agents. The effects of O-acylation to CSNFs were analyzed in detail. FT-IR, 1H NMR and elemental analysis indicated that the hydroxyl groups of chitosan in CSNFs were acylated in 2h. XRD spectra indicated that the O-acylation modification altered the crystal structure of the native fibers and the acyl substituents packed in a laterally aligned and layered structure. SEM examinations showed that the acylation modification could effectively control the fibrous structure of CSNFs and improve their stability in moist environment. The O-acylated CSNFs generally have an average diameter about 100nm except for laurelated CSNFs (∼200nm). Water contact angle measurement indicated that the wetting properties of O-acylated CSNFs were affected by the length of acyl side chains. This fiber acylation strategy can tune the material properties of CSNFs and expand their potential applications.

Anti-hepatocarcinoma effects of berberine-nanostructured lipid carriers against human HepG2, Huh7, and EC9706 cancer cell lines

Hepatocarcinoma and esophageal squamous cell carcinomas threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma and esophageal carcinoma to chemotherapy. Berberine (Ber), an isoquinoline derivative alkaloid, has a wide range of pharmacological properties and is considered to have anti-hepatocarcinoma and antiesophageal carcinoma effects. However its low oral bioavailability restricts its wide application. In this report, Ber loaded nanostructured lipid carriers (Ber-NLC) was prepared by hot melting and then high pressure homogenization technique. The in vitro anti-hepatocarcinoma and antiesophageal carcinoma effects of Ber-NLC relative to efficacy of bulk Ber were evaluated. The particle size and zeta potential of Ber-NLC were 189.3 ± 3.7 nm and −19.3 ± 1.4 mV, respectively. MTT assay showed that Ber-NLC effectively inhibited the proliferation of human HepG2 and Huh7 and EC9706 cells, and the corresponding IC50 value was 9.1 μg/ml, 4.4 μg/ml, and 6.3 μg/ml (18.3μg/ml, 6.5μg/ml, and 12.4μg/ml μg/ml of bulk Ber solution), respectively. These results suggest that the delivery of Ber-NLC is a promising approach for treating tumors.

Evaluation of Both Free Radical Scavenging Capacity and Antioxidative Damage Effect of Polydatin

Cellular damage such as oxidation and lipid peroxidation, and DNA damage induced by free-radicals like reactive oxygen species, has been implicated in several diseases. Radicals generated by 2,2-azobis (2-amidino-propane) dihydrochloride (AAPH) are similar to physiologically active ones. In this study we found that polydatin, a resveratrol natural precursor derived from many sources, has the capacity of free radical scavenging and antioxidative damage. Using free radical scavenging assays, the IC50 values of polydatin were 19.25 and 5.29 μg/ml with the DPPH and the ABTS assay, respectively, and 0.125 mg ferrous sulfate/1 mg polydatin with the FRAP assay. With the AAPH-induced oxidative injury cell model assay, polydatin showed a strong protective effect against the human liver tumor HepG2 cell oxidative stress damage. These results indicate that the antioxidant properties of polydatin have great potential for use as an alternative to more toxic synthetic antioxidants as an additive in food, cosmetics and pharmaceutical preparations for the treatment of oxidative diseases.

In vitro and in vivo antitumor efficacy of berberine-nanostructured lipid carriers against H22 tumor

Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Berberine (Ber), an isoquinoline derivative alkaloid, has a wide range of pharmacological properties and is considered to have anti-hepatocarcinoma effects. However its low oral bioavailability restricts its wide application. In this report, Ber loaded nanostructured lipid carriers (Ber-NLC) was prepared by hot melting and then high pressure homogenization technique. Both in vitro and in vivo anti-hepatocarcinoma effects of Ber-NLC relative to efficacy of bulk Ber were evaluated. The particle size and zeta potential of Ber-NLC were 189.3 nm and −19.3 mV, respectively. MTT assay showed that Ber-NLC effectively inhibited the proliferation of H22 cells, and the corresponding IC50 values were 6.3 μg/ml (22.1 μg/ml of bulk Ber). In vivo studies also showed higher antitumor efficacy, and inhibition rates was 68.3 % (41.4 % of bulk Ber) at 100 mg/kg intragastric administration in the H22 solid tumor bearing mice. These results suggest that the delivery of Ber-NLC is a promising approach for treating tumors.

Inhibitory efficacy of the quantified prunellae spica extract on H22 tumor bearing mice

Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistence of the advanced hepatocarcinoma to chemotherapy. In this report, we assessed the antitumor activity of a prunellae spica aqueous extract (PSE) in vitro and in vivo. PSE was quantified by HPLC and UV. MTT assay showed that PSE did not effectively inhibit the growth of H22 cells. The in vivo anti-tumor activity was assessed by using the mice bearing H22 tumor. In vivo studies showed the higher antitumor efficacy of PSE without significant side effect assessed by the reduced tumor weight, and the extended survival time of the mice bearing H22 solid and ascites tumor. Collectively, PSE is a promising Chinese medicinal herb for treating hepatocarcinoma.

Determination of aloin In aloe extracts from different companies by HPLC-UV

To give some foundation for quality standards of the aloe extracts, by studying the contents of the aloin in aloe extracts and evaluating scientifically the quality of the aloe extracts from different companies. The chromatographic separation was performed on a SunFire C18 column (250mm×4.6mm, 5 μm). The mobile phase comprised acetonitrile-water (25:75, V/V,) at a flow rate of 1.0 mL/min. The detection wavelength was set at 355nm. There was a great difference in the aloe extracts from different companies. There was a good linear relationship between peak area and the injection volume over the range of 2.5-20μL (R2 = 0.9992). The average spike recovery of the aloin was 99.62%, With a RSD of 1.20%(n=6). The contents of aloe extracts from different companies were 90.64-263.11mg/g. This method is simple, fast and the result is accurate and reliable and can be used for the determination of the aloin in aloe extracts.

Anti-hepatocarcinoma effects of puerarin-nanoethosomes against human HepG2 cells

Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Puerarin (Pue), a major active ingredient in the traditional Chinese medicine Gegen, has a wide range of pharmacological properties and is considered to have anti-hepatocarcinoma effects. However its low oral bioavailability restricts its wide application. In this report, Pue loaded nanoethosomes(Pue-NE) was prepared by high pressure homogenization technique. The in vitro anti-hepatocarcinoma effects of Pue-NE relative to efficacy of bulk Pue were evaluated. The particle size and zeta potential of Pue-NE were 91.8 nm and -6.1 mV, respectively. MTT assay showed that Pue-NE effectively inhibited the proliferation of HepG2 cells, and the corresponding IC50 values of Pue-NE and bulk Pue were 1.77 and 5.73 μg/ml. These results suggest that the delivery of Pue-NE is a promising approach for treating tumors.

Evaluation of free-radical scavenging and antioxidant activities of polydatin nanoethosomes

Cellular damage induced by free-radicals like reactive oxygen species has been implicated in several diseases. The ROS radicals like alkoxy radical(RO-) and peroxy radical (ROO-) are similar to those that are physiologically active and thus might initiate a cascade of intracellular toxic events leading to DNA damage and cell death. Hence naturally anti-oxidant play a vital role in combating these conditions. In this study, polydatin nanoethosomes (Pol-NE) was prepared by high pressure homogenization technique. The effects of Pol-NE on free radical scavenging and antioxidant was investigated. The particle size and zeta potential of Pol-NE was 96.1±4.5 nm and -17.31±1.67 mV, respectively. By free radical scavenging and antioxidant assays, the IC50 value of Pol-NE were 28.71, 9.83 μg/mL with DPPH, ABTS assay respectively, and 0.143 mg ferrous sulfate/1 mg Pol-NE with FRAP assay. These results indicated that the antioxidant properties of Pol-NE hold great potential used as an alternative to more toxic synthetic anti-oxidants as an additive in food, cosmetic and pharmaceutical preparations for the oxidative diseases treatment.

Anti-arthritic activities of ethanol extracts of Circaea mollis Sieb. & Zucc. (whole plant) in rodents

ETHNOPHARMACOLOGICAL RELEVANCE Circaea mollis Sieb. & Zucc., a genus of Circaea that follows Onagraceae, has been used for centuries as a folk herb in traditional Chinese medicine (TCM) and Hani Ethnopharmacy for the treatment of joint swelling and pain in rheumatoid arthritis. AIM OF THE STUDY This study was designed to confirm anti-arthritic effects and its underlying mechanism of ethanol extracts of Circaea mollis Sieb. & Zucc. (EEC), which may contribute to provide the pharmacological basis in the treatment of rheumatoid disease. MATERIALS AND METHODS Dimethylbenzene (DMB)-induced inflammatory swelling model, hot-plate pain model in mice and Freunds complete adjuvant (FCA)-induced arthritis model in rats were used to evaluate the anti-arthritis effect of EEC. Arthritis severity was done by measuring inflammatory swelling, pain threshol, paw swelling, arthritis index, body weight, spleen index and thymus index. The levels of TNF-α, IL-1β and IL-10 in sera were measured using ELISA. The pathological change of the ankle joint was also done. Phenolic composition of EEC was analyzed. RESULTS EEC inhibited inflammatory swelling and increased heat-induced pain threshold in mice. Furthermore, EEC significantly alleviated paw swelling and arthritis index, decreasing the spleen index and thymus index. Besides, EEC down-regulated the serum TNF-α and IL-1β, and increased the production of serum IL-10 in FCA-induced rats. Histopathological examination demonstrated that EEC can effectively relieve synovial hyperplasia, control the infiltration of the inflammatory and protect cartilage from destruction. CONCLUSION Our work demonstrated that EEC possessed the potential therapeutic effect against arthritis in rodents which was attributed to modulating proinflammatory cytokines TNF-α, IL-1β and anti-inflammatory factors IL-10. Flavonoids and polyphenols may contribute to the therapeutic effect of EEC on arthritis.

Anti-hepatocarcinoma effects of resveratrol nanoethosomes against human HepG2 cells

Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Resveratrol (Res) has been widely investigated with its strong anti-tumor activity. However, its low oral bioavailability restricts its wide application. In this study, we prepared resveratrol nanoethosomes (ResN) via ethanol injection method. The in vitro anti-hepatocarcinoma effects of ResN relative to efficacy of bulk Res were evaluated on proliferation and apoptosis of human HepG2 cells. ResN were spherical vesicles and its particle diameter, zeta potential were (115.8 ± 1.3) nm and (-12.8 ± 1.9) mV, respectively. ResN exhibited significant inhibitory effects against human HepG2 cells by MTT assay, and the IC50 value was 49.2 μg/ml (105.4 μg/ml of Res bulk solution). By flow cytometry assay, there was an increase in G2/M phase cells treated with ResN. The results demonstrated ResN could effectively block the G2/M phase of HepG2 cells, which can also enhance the inhibitory effect of Res against HepG2 cells.