Biotransformation of ginsenoside Rb1 and Rd to four rare ginsenosides and evaluation of their anti-melanogenic effects.

Improving physiological activity of primary ginsenosides through biotransformation is of great significance for food applications. In this study, gynostapenoside XVII, gynostapenoside LXXV, ginsenoside F2, and ginsenoside CK were obtained by enzymolysis of an accessible extract composed of ginsenoside Rb1 and Rd. Their effects on melanin content and tyrosinase activity were compared in vitro, and molecular docking simulation was employed to elucidate the interaction between tyrosinase and individual saponin. The results indicated that four rare ginsenosides decreased tyrosinase activity, melanin content and microphthalmia-associated transcription factor (MITF) expression level, more greatly than their primary ginsenosides, and they were more readily to bind with ASP10 and GLY68 at active site of tyrosinase to inhibit tyrosinase activity as well. These findings suggested that the rare ginsenosides obtained by enzymolysis had excellent anti-melanogenic effect, which could expand the application of ginsenosides in the field of functional foods and health supplements.

Construction of Fe3O4@α-glucosidase magnetic nanoparticles for ligand fishing of α-glucosidase inhibitors from a natural tonic Epimedii Folium.

Inhibition of α-glucosidase activity is an effective way for treatment of type 2 diabetes mellitus. Epimedii Folium is an important source of α-glucosidase inhibitors (AGIs), however bioactive compounds and pharmacological mechanisms remained unclear. In this study, a novel strategy was established, which harnessed α-glucosidase functionalized magnetic beads to fish out potential AGIs, followed by UPLC-MS/MS analysis for their identification. Furthermore, molecular docking was employed to predict binding patterns between the AGIs and the enzyme, and IC50 values was estimated as well. After response surface methodology optimization, the highest activity of Fe3O4@α-glucosidase has been achieved when 1.17 mg/mL of α-glucosidase was immobilized in phosphate buffer (pH 6.81) for 4.22 h. Moreover, eight flavonoids were fished out from the extract of Epimedii Folium, and then identified to be epimedin A, epimedin B, epimedin C, icariin, sagittatoside A, sagittatoside B, 2"-O-rhamnosyl icariside II and baohuoside I. All of them were further confirmed to be AGIs through in vitro inhibitory assay and molecular docking. Among those, baohuoside I and sagittatoside B possessed stronger inhibitory activity than acarbose. The approach has a significant prospect in conveniently screening bioactive compounds that target various receptors, which provided an efficient platform for new drug development from natural products.

Physiologic Electrical Fields Direct Retinal Ganglion Cell Axon Growth In Vitro.

Purpose: The purpose of this study was to characterize the ability of applied electrical fields (EFs) to direct retinal ganglion cell (RGC) axon growth as well as to assess whether Rho GTPases play a role in translating electrical cues to directional cues. Methods: Full-thickness, early postnatal mouse retina was cultured in electrotaxis chambers and exposed to EFs of varying strengths (50-200 mV/mm). The direction of RGC axon growth was quantified from time-lapsed videos. The rate of axon growth and responsiveness to changes in EF polarity were also assessed. The effect of toxin B, a broad-spectrum inhibitor of Rho GTPase signaling, and Z62954982, a selective inhibitor of Rac1, on EF-directed growth was determined. Results: In the absence of an EF, RGC axons demonstrated indiscriminate directional growth from the explant edge. Retinal cultures exposed to an EF of 100 and 200 mV/mm showed markedly asymmetric growth, with 74.2% and 81.2% of axons oriented toward the cathode, respectively (P < 0.001). RGC axons responded to acute changes in EF polarity by redirecting their growth toward the "new" cathode. This galvanotropic effect was partially neutralized by toxin B and Rac1 inhibitor Z62954982. Conclusions: RGC axons exhibit cathode-directed growth in the presence of an EF. This effect is mediated in part by the Rho GTPase signaling cascade.

The mechanism of high contents of oil and oleic acid revealed by transcriptomic and lipidomic analysis during embryogenesis in Carya cathayensis Sarg.

BACKGROUND: Hickory (Carya cathayensis Sarg.) accumulates more than 70% oil and 90% unsaturated fatty acids with considerably high oleic acid in its mature embryo. The concurrent global trancriptomic and lipidomic analyses provided a framework for better understanding of glycerolipid biosynthesis and metabolism in the hickory nut. RESULTS: The synthetical regulation of numerous leading lipid-related genes harmonized with the oil accumulation and fatty acid conversion in embryo development. The high level of ACCase correlated positively with fatty acids de novo synthesis, and the synergy of DGAT2 and PDAT promoted the TAG assembly, and oleosins, caleosins and steroleosins were transcribed considerably high for timely energy reserve in oil body. Glycolysis possibly provided sufficient precursors and energy for lipid synthesis. The perfect harmonization of the high level of SAD with low level of FAD2 facilitated the oleic acid accumulation. And the ratio of FATA/FATB or SAD/FATB was proposed for determining the saturated degree of oil. The gene multi-copy event was generated probably for accommodating various survival environments. A thermotolerant defense system including TAG hydrolysis determinants, heat shock proteins, and high ratio of MUFA to PUFA constrained the lipid degradation and provided a guarantee for high lipid content. A batch of potential genes recruited from the co-expression network helps us to understand the lipid synthesis and the response to high temperature better. CONCLUSIONS: The high transcriptional levels of key genes in lipid synthesis promoted the oil accumulation, and the harmonious expression of key ones for unsaturated fatty acids led oleic acid to high levels.

Wogonin inhibits the proliferation of myelodysplastic syndrome cells through the induction of cell cycle arrest and apoptosis.

The present study aimed to assess the effects of the flavonoid, wogonin, and its underlying mechanism on myelodysplastic syndrome (MDS) in SKM-1 cells. In the present study, wogonin inhibited the cell proliferation of SKM­1 cells in a dose­ and time­dependent manner, with the concentration required to yield a half maximal inhibitory concentration (IC50) of 212.1 µmol/l at 24 h, and 43.4 µmol/l at 72 h. Furthermore, wogonin induced cell cycle arrest at the G0/G1 phase and induced the apoptosis of the SKM­1 cells, which possibly accounted for the antiproliferative effects of wogonin. Notably, the data in the present study revealed that wogonin upregulated the expression of p21Cip1 and p27Kip1, and downregulated the expression of cyclin D1 and cyclin­dependent kinase 4, causing a G0/G1 phase arrest, halting cell cycle progression, and inducing apoptosis in the MDS cells, which was mediated by the mitochondrial pathway through a modulation of the ratio of Bcl­2 to Bax. Therefore, the present study suggests that wogonin may be a logical therapeutic target in the treatment of MDS.

Rapid quantitative analysis of diosgenin in the tubers of Dioscorea zingiberensis C.H. Wright by coupling cellulose enzymolysis and two-phase acid hydrolysis in tandem with HPLC-UV.

A rapid method was developed to quantify diosgenin in Rhizoma Dioscoreae Zingiberensis. For the first time, sample solution was prepared by coupling pretreatment of raw material in cellulase and two-phase acid hydrolysis. After reconstitution, analysis was carried out on a C18 column, at 30°C, with acetonitrile and water (70:30, v/v) as mobile phase with flow rate of 1.0 mL min(- 1). Detection was carried out at 202 nm. Good linearity (r(2) = 0.9998) was established between concentration of analyte and peak area. The precision was >99% and the RSD of diosgenin contents for repeatability was 1.81%. The accuracy was supported with recoveries at 98.8%, 101.6% and 101.2%. The sample solution prepared using the proposed method contained higher content of diosgenin and was stable for 48 h. Due to the high efficiency of sample preparation and high reliability of the HPLC method, it is feasible to use this method for routine analysis of diosgenin in the herb.

Multifunctional magnetic Fe3O4 nanoparticles combined with chemotherapy and hyperthermia to overcome multidrug resistance.

BACKGROUND: Multidrug resistance in cancer is a major obstacle for clinical therapeutics, and is the reason for 90% of treatment failures. This study investigated the efficiency of novel multifunctional Fe(3)O(4) magnetic nanoparticles (Fe(3)O(4)-MNP) combined with chemotherapy and hyperthermia for overcoming multidrug resistance in an in vivo model of leukemia. METHODS: Nude mice with tumor xenografts were randomly divided into a control group, and the treatment groups were allocated to receive daunorubicin, 5-bromotetrandrine (5-BrTet) and daunorubicin, Fe(3)O(4)-MNP, and Fe(3)O(4)-MNP coloaded with daunorubicin and 5-bromotetrandrine (Fe(3)O(4)-MNP-DNR-5-BrTet), with hyperthermia in an alternating magnetic field. We investigated tumor volume and pathology, as well as P-glycoprotein, Bcl-2, Bax, and caspase-3 protein expression to elucidate the effect of multimodal treatment on overcoming multidrug resistance. RESULTS: Fe(3)O(4)-MNP played a role in increasing tumor temperature during hyperthermia. Tumors became significantly smaller, and apoptosis of cells was observed in both the Fe(3)O(4)-MNP and Fe(3)O(4)-MNP-DNR-5-BrTet groups, especially in the Fe(3)O(4)-MNP-DNR-5-BrTet group, while tumor volumes in the other groups had increased after treatment for 12 days. Furthermore, Fe(3)O(4)-MNP-DNR-5-BrTet with hyperthermia noticeably decreased P-glycoprotein and Bcl-2 expression, and markedly increased Bax and caspase-3 expression. CONCLUSION: Fe(3)O(4)-MNP-DNR-5-BrTet with hyperthermia may be a potential approach for reversal of multidrug resistance in the treatment of leukemia.

Effect of magnetic nanoparticles on apoptosis and cell cycle induced by wogonin in Raji cells.

Traditional Chinese medicine is gradually becoming a new source of anticancer drugs. One such example is wogonin, which is cytotoxic to various cancer cell lines in vitro. However, due to its low water solubility, wogonin is restricted to clinical administration. Recently, the application of drug-coated magnetic nanoparticles (MNPs) to increase water solubility of the drug and to enhance its chemotherapeutic efficiency has attracted much attention. In this study, wogonin was conjugated with the drug delivery system of MNPs by mechanical absorption polymerization to fabricate wogonin-loaded MNPs. It was demonstrated that MNPs could strengthen wogonin-induced cell inhibition, apoptosis, and cell cycle arrest in Raji cells by methylthiazol tetrazolium assay, flow cytometer assay, and nuclear 4',6-diamidino-2-phenylindole staining. Furthermore, the molecular mechanisms of these phenomena were explored by western blot, in which the protein levels of caspase 8 and caspase 3 were increased significantly while those of survivin and cyclin E were decreased significantly in wogonin-MNPs group. These findings suggest that the combination of wogonin and MNPs provides a promising strategy for lymphoma therapy.

The changes of T lymphocytes and cytokines in ICR mice fed with Fe3O4 magnetic nanoparticles.

The aim of this article is to study the changes inhibited T lymphocytes and cytokines related to the cellular immunity in ICR (imprinting control region) mice fed with Fe(3)O(4) magnetic nanoparticles (Fe(3)O(4)-MNPs). The Fe(3)O(4)-MNPs were synthesized, and their characteristics such as particle size, zeta potential, and X-ray diffraction patterns were measured and determined. All ICR mice were sacrificed after being exposed to 0, 300, 600, and 1200 mg/kg of Fe(3)O(4)-MNPs by single gastric administration for 14 days. Splenocytes proliferation was indicated with stimulate index by MTT assay; release of cytokines in the serum of ICR mice was detected by enzyme-linked immunosorbent assay, and the phenotypic analyses of T-lymphocyte subsets were performed using flow cytometry. Our results indicated that there were no significant differences in splenocyte proliferation and release of cytokines between exposed and control groups. Furthermore, there was no significant difference in the proportions of T-lymphocyte subsets in the low-dose Fe(3)O(4)-MNPs group when compared to the control group, but the proportions of CD3(+)CD4(+) and CD3(+)CD8(+) T-lymphocyte subsets both in the medium- and high-dose Fe(3)O(4)-MNPs groups were higher than those in the control group. It is concluded that a high dose of Fe(3)O(4)-MNPs, to some extent, could influence in vivo immune function of normal ICR mice.

[Influence of magnetic Fe3O4 nanoparticle on functions of lymphocytes and macrophages in mice].

This study was purposed to investigate the effects of magnetic nanoparticle of Fe3O4 (Fe3O4-MNPs) on murine immune system. ICR mice were assigned randomly into four groups which were treated with normal saline, low, middle and high dose of MNP-Fe3O4 respectively. The mice were killed after being exposed by intragastric administration for 2 weeks. The ratios of spleen weight to body weight, lymphocyte transformation rate in spleen suspension and phagocytic index of macrophage in abdominal cavity were detected. The results showed that the ratios of spleen weight to body weight in Fe3O4-MNP groups were not significantly different in comparison with the control (p > 0.05). The lymphocyte transformation rate in spleen suspension in Fe3O4-MNP groups were all higher than that in control group (-0.1775 +/- 0.0246), especially in the middle dose group (0.1833 +/- 0.0593) (p < 0.05), and the phagocytic index of macrophages in abdominal cavity of middle dose group (0.2051 +/- 0.0213) was higher than that of control group and other two Fe3O4-MNP group (low dose 0.1538 +/- 0.0100, high dose 0.1511 +/- 0.0184) (p < 0.05). It is concluded that suitable dose of Fe3O4-MNP can enhance the cellular immune activity and phagocytic function of macrophages of mice.

Synergistic effect of magnetic nanoparticles of Fe(3)O(4) with gambogic acid on apoptosis of K562 leukemia cells.

Gambogic acid (GA) has a significant anticancer effect on a wide variety of solid tumors. Recently, many nanoparticles have been introduced as drug-delivery systems to enhance the efficiency of anticancer drug delivery. The aim of this study was to investigate the potential benefit of combination therapy with GA and magnetic nanoparticles of Fe(3)O(4) (MNPs-Fe(3)O(4)). The proliferation of K562 cells and their cytotoxicity were evaluated by MTT assay. Cell apoptosis was observed and analyzed by microscope and flow cytometry, respectively. Furthermore, real-time polymerase chain reaction and Western blotting analyses were performed to examine gene transcription and protein expression, respectively. The results showed that MNPs-Fe(3)O(4) dramatically enhanced GA-induced cytotoxicity and apoptosis in K562 cells. The typical morphological features of apoptosis treated with GA and MNPs-Fe(3)O(4) were observed under an optical microscope and a fluorescence microscope, respectively. The transcription of caspase-3 and bax gene in the group treated with GA and MNPs-Fe(3)O(4) was higher than that in the GA-alone group or MNPs-Fe(3)O(4)-alone group, but the transcription of bcl-2, nuclear factor-kappaB, and survivin degraded as did the expression of corresponding proteins in K562 cells. Our data suggests a potential clinical application of a combination of GA and MNPs-Fe(3)O(4) in leukemia therapy.

[Study on tissue culture and rapid propagation of Atractylodes macrocephala].

A study was conducted by tissue culture on the explant of Atractylodes macrocephala Koidz.. The result showed that NAA was a leading factor for induction of callus from leaf blades and the petiole as well as bud differentiation. MS + BA 1.0 mg/L + NAA 0.3 mg/L + GA3 0.2 mg/L was an optimal medium for induction of callus from leaf blades and the petiole and for the bud differentation also. MS + BA 3.0 mg/L + IBA 0.5 mg/L was suitable for the proliferation of axillary buds, with an induction rate of 95%. 1/2MS + IBA 0.1 - 0.5 mg/L was optimum for rooting, with a rooting percentage more than 90%. The survival rate of transplanted plantlets was more than 90%.