Comparative Assessment of the Antioxidant Activities among the Extracts of Different Parts of Clausena lansium (Lour.) Skeels in Human Gingival Fibroblast Cells

Clausena lansium (Lour.) Skeels (wampee) is an outstanding natural plant with medicinal properties. The aim of this study was to compare the cytoprotective effects of four parts of wampee under oxidative stress. The aqueous extracts of leaf, peel, pulp, and seed were tested for the proliferation effects on human gingival fibroblast (HGF) cells and the protective effects in the hydrogen peroxide-induced HGF model. Furthermore, the total glutathione assay and identification of rutin by high-performance liquid chromatography were carried out to attempt to determine whether the cytoprotective effects were related to the total glutathione (GSH) stability and rutin content. The results showed that all of the extracts had no cytotoxicity to HGF at tested concentrations ranging from 50 to 5000 μg/ml during 24 h, and the leaf, pulp, and seed extracts increased proliferation of HGF at relatively high concentrations. All the extracts except for the seed extract significantly decreased the production of reactive oxygen species, and the peel extracts exhibited the most effective antioxidant effect. The leaf extract had the highest anticytotoxicity and GSH stabilization effect in the HGF challenged with hydrogen peroxide. In addition, the relative content of rutin in peel and leaf extracts was higher than that in pulp and seed. The results of GSH assay and rutin identification suggest that different cellular protective effects among the four parts of wampee are partially related to the GSH stabilization and rutin content. These findings provide a scientific basis for the antioxidant effect-related biological activities of wampee extracts.

Translational Investigation of Turmeric for Arthritis Treatment: A Review of Lessons Learned

Turmeric rhizome has been used for centuries to combat inflammation, including joint inflammation in arthritis. However, scientific evidence of efficacy and mechanism of action and a systematic evaluation of the biological activity of turmeric components for the treatment of inflammation have been lacking. This review will summarize the results of recently published studies that we have conducted to address each of these specific areas of inquiry using an animal model of rheumatoid arthritis.

Oxidative stress induced by zearalenone in porcine granulosa cells and its rescue by curcumin in vitro

Oxidative stress (OS), as a signal of aberrant intracellular mechanisms, plays key roles in maintaining homeostasis for organisms. The occurrence of OS due to the disorder of normal cellular redox balance indicates the overproduction of reactive oxygen species (ROS) and/or deficiency of antioxidants. Once the balance is broken down, repression of oxidative stress is one of the most effective ways to alleviate it. Ongoing studies provide remarkable evidence that oxidative stress is involved in reproductive toxicity induced by various stimuli, such as environmental toxicants and food toxicity. Zearalenone (ZEA), as a toxic compound existing in contaminated food products, is found to induce mycotoxicosis that has a significant impact on the reproduction of domestic animals, especially pigs. However, there is no information about how ROS and oxidative stress is involved in the influence of ZEA on porcine granulosa cells, or whether the stress can be rescued by curcumin. In this study, ZEA-induced effect on porcine granulosa cells was investigated at low concentrations (15 μM, 30 μM and 60 μM). In vitro ROS levels, the mRNA level and activity of superoxide dismutase, glutathione peroxidase and catalase were obtained. The results showed that in comparison with negative control, ZEA increased oxidative stress with higher ROS levels, reduced the expression and activity of antioxidative enzymes, increased the intensity of fluorogenic probes 2', 7'-Dichlorodihydrofluorescin diacetate and dihydroethidium in flow cytometry assay and fluorescence microscopy. Meanwhile, the activity of glutathione (GSH) did not change obviously following 60 μM ZEA treatment. Furthermore, the underlying protective mechanisms of curcumin on the ZEA-treated porcine granulosa cells were investigated. The data revealed that curcumin pre-treatment significantly suppressed ZEA-induced oxidative stress. Collectively, porcine granulosa cells were sensitive to ZEA, which may induce oxidative stress. The findings from this study clearly demonstrate that curcumin is effective to reduce the dysregulation of cellular redox balance on porcine granulosa cells in vitro and should be further investigated for its protective role against ZEA in animals.

Binding analysis for interaction of diacetylcurcumin with β-casein nanoparticles by using fluorescence spectroscopy and molecular docking calculations

The interaction of diacetylcurcumin (DAC), as a novel synthetic derivative of curcumin, with bovine β-casein (an abundant milk protein that is highly amphiphilic and self assembles into stable micellar nanoparticles in aqueous solution) was investigated using fluorescence quenching experiments, Forster energy transfer measurements and molecular docking calculations. The fluorescence quenching measurements revealed the presence of a single binding site on β-casein for DAC with the binding constant value equals to (4.40±0.03)×10(4)M(-1). Forster energy transfer measurements suggested that the distance between bound DAC and Trp143 residue is higher than the respective critical distance, hence, the static quenching is more likely responsible for fluorescence quenching other than the mechanism of non-radiative energy transfer. Our results from molecular docking calculations indicated that binding of DAC to β-casein predominantly occurred through hydrophobic contacts in the hydrophobic core of protein. Additionally, in vitro investigation of the cytotoxicity of free DAC and DAC-β-casein complex in human breast cancer cell line MCF7 revealed the higher cytotoxic effect of DAC-β-casein complex.

Curcumin inhibits AP-2γ-induced apoptosis in the human malignant testicular germ cells in vitro

AIM

To investigate the effects of curcumin on proliferation and apoptosis in testicular cancer cells in vitro and to investigate its molecular mechanisms of action.

METHODS

NTera-2 human malignant testicular germ cell line and F9 mouse teratocarcinoma stem cell line were used. The anti-proliferative effect was examined using MTT and colony formation assays. Hoechst 33258 staining, TUNEL and Annexin V-FITC/PI staining assays were used to analyze cell apoptosis. Protein expression was examined with Western blot analysis and immunocytochemical staining.

RESULTS

Curcumin (5, 10 and 15 μmol/L) inhibited the viability of NTera-2 cells in dose- and time-dependent manners. Curcumin significantly inhibited the colony formation in both NTera-2 and F9 cells. Curcumin dose-dependently induced apoptosis of NTera-2 cells by reducing FasL expression and Bcl-2-to-Bax ratio, and activating caspase-9, -8 and -3. Furthermore, curcumin dose-dependently reduced the expression of AP transcription factor AP-2γ in NTera-2 cells, whereas the pretreatment with the proteasome inhibitor MG132 blocked both the curcumin-induced reduction of AP-2γ and antiproliferative effect. Curcumin inhibited ErbB2 expression, and decreased the phosphorylation of Akt and ERK in NTera-2 cells.

CONCLUSION

Curcumin induces apoptosis and inhibits proliferation in NTera-2 cells via the inhibition of AP-2γ-mediated downstream cell survival signaling pathways.

Curcumin ameloriates heat stress via inhibition of oxidative stress and modulation of Nrf2/HO-1 pathway in quail

Curcumin, a natural polyphenol in the spice turmeric, exhibits antioxidant and antiinflammatory properties. This study was conducted to elucidate the action mode of curcumin alleviation of oxidative stress in heat-stressed quail. A total of 180 birds (10 d old) were assigned randomly to be reared at either 22°C (Thermoneutral) or 34°C (Heat stress) for 8 h/d (0900-1700) until the age of 42 d. Birds in both environments were randomly fed 1 of 3 diets: basal diet and basal diet added with 0, 200 or 400 mg of curcumin per kg of diet. Each of the 2×3 factorially arranged experimental groups was replicated in 10 cages, each containing three birds. In response to increasing supplemental curcumin level, there were linear increases in cumulative feed intake, final body weight, and weight gain, and nuclear factor erythroid 2-related factor two level and heme oxygenase one level; linear decreases in feed efficiency, serum, muscle and liver malondialdehyde level, respectively and inflammatory transcription factor, nuclear factor-κB and heat shock proteins 70 level (P<0.0001 for all). The results indicated that curcumin alleviates oxidative stress through modulating the hepatic nuclear transcription factors and heat shock proteins 70 in heat-stressed quails.

Development of curcuminoids loaded poly(butyl) cyanoacrylate nanoparticles: Physicochemical characterization and stability study

Curcumininoids, obtained from the rhizomes of Curcuma longa L., Zingiberaceae (turmeric), are the most widely used phytoconstituent in food industry and recently for its therapeutic activity. It has very wide spectrum of therapeutic use like in inflammation, psoriasis, various tumors, wound healing and also in neurodegenerative diseases like Alzheimer's disease. But its highly lipophilic nature and very poor bioavailability hampers its therapeutic usefulness. Poly(butyl) cyanoacrylate (PBCA) nanoparticles coated with poloxamer 188 containing curcuminoids were prepared by anionic polymerization using solvent evaporation method. The particle size and zeta potential of prepared liposomes was 178nm and -28.33 respectively with 77.99% encapsulation efficiency. The TEM study revealed the spherical nature of the prepared nanoparticles alongwith confirmation of particle size. The polymerization and entrapment of curcuminoids was confirmed using H(1) NMR study by comparing the spectra of nanoparticles with that of curcuminoids. DSC study revealed that curcuminoids was entrapped inside the nanoparticles in molecular dispersion form. In vitro release study showed that the prepared PBCA nanoparticles are capable of controlled drug release (following matrix model) for extended period of time with higher release in acidic environment compared to PB 7.4 suggesting the usefulness of the prepared nanoparticles for intracellular delivery. The mean particle size, zeta potential and the amount of curcuminoids showed no significant changes compared to the freshly prepared PBCA nanoparticles after storage for 6 months at 40 degrees C/75% RH in the presence and absence of sunlight.

Suppression of the nuclear factor-kappaB activation pathway by spice-derived phytochemicals: reasoning for seasoning

The activation of nuclear transcription factor kappaB has now been linked with a variety of inflammatory diseases, including cancer, atherosclerosis, myocardial infarction, diabetes, allergy, asthma, arthritis, Crohn's disease, multiple sclerosis, Alzheimer's disease, osteoporosis, psoriasis, septic shock, and AIDS. Extensive research in the last few years has shown that the pathway that activates this transcription factor can be interrupted by phytochemicals derived from spices such as turmeric (curcumin), red pepper (capsaicin), cloves (eugenol), ginger (gingerol), cumin, anise, and fennel (anethol), basil and rosemary (ursolic acid), garlic (diallyl sulfide, S-allylmercaptocysteine, ajoene), and pomegranate (ellagic acid). For the first time, therefore, research provides "reasoning for seasoning."