Stabilization of ginger essential oil Pickering emulsions by pineapple cellulose nanocrystals.

Pickering emulsions (PE) are systems made up of two incompatible fluids, these are stabilized by solid organic or inorganic particles located on their interface. Cellulose nanocrystals (CNCs) are sustainable and biocompatible value-added naturally occurring biomolecules which are being investigated as PE stabilizers in the cosmetic, food, and pharmaceutical industries. The objective of this research was to investigate the efficacy of pineapple cellulose nanocrystals as stabilizers for a ginger essential oil-in-water Pickering emulsion. Anionic pineapple cellulose nanocrystals were prepared by acid hydrolysis. Ginger essential oil-in-water emulsions were prepared by ultrasonication. Pineapple CNC produced stable Pickering emulsions with surface average droplet size of 4.3 µm-6.2 µm, high negative zeta potential, high viscosity, and high adsorption at the interface. Pickering emulsions by ultrasonication were stable against droplet coalescence, phase separation, and droplet flocculation for at least 8 weeks at 25 °C or 40 °C at various droplet sizes. The emulsion droplet size and volume density (droplet size distribution) were evaluated by varying the particle concentration (CNC 0.25 g/100 ml or 0.50 g/100 ml) and/or oil fraction (10-20 g/100 ml). At constant oil fraction, the emulsion viscosity increased as the nanocrystal concentration increased. The cellulose nanocrystal-stabilized ginger oil-Pickering emulsions exhibited shear-thinning characteristics of a pseudo-plastic fluid. Pineapple nanocellulose crystal -stabilized ginger oil-Pickering emulsions exhibited high stability with a creaming index of zero. CNC was found to be an effective Pickering stabilizer for oil-in-water emulsions in various food applications.

Sodium Propionate or Sodium Butyrate Promotes Fatty Acid Oxidation in HepG2 Cells Under Oxidative Stress.

The beneficial effects of sodium butyrate (NaB) and sodium propionate (NaP) on fatty acid oxidation (FAO) genes and production of proinflammatory cytokines related to nonalcoholic fatty liver disease (NAFLD) were evaluated using HepG2 human liver hepatocellular carcinoma cells exposed to palmitate/oleate or lipopolysaccharides (LPSs) as a model. The results showed that NaP or NaB was able to promote FAO, regulate lipolysis, and reduce reactive oxygen species production by significantly increasing the mRNA expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), peroxisome proliferator-activated receptor alpha (PPARα), adipose triglyceride lipase (ATGL), carnitine palmitoyltransferase 1 alpha (CPT1α), fibroblast growth factor 21 (FGF21), and uncoupling protein 2 (UCP2) in HepG2 cells. Together, NaP and NaB may produce greater effects by increasing CPT1α, PPARα, and UCP2 mRNA expression in LPS-treated HepG2 cells and by increasing CPT1α and ATGL mRNA expression in palmitate-/oleate-treated HepG2 cells. Only NaP treatment significantly increased FGF21 mRNA expression in palmitate-/oleate-treated HepG2 cells. The enzyme-linked immunosorbent assay results revealed that only pretreatment with LPSs and not palmitate/oleate significantly increased tumor necrosis factor alpha (TNF-α) expression in HepG2 cells. NaP alone or in combination with NaB significantly decreased TNF-α expression in LPS-induced HepG2 cells. The expression of interleukin-8 in both models showed no significant differences in all treatments. NaP and NaB show potential for in vivo studies on NAFLD.

Effects of red raspberry polyphenols and metabolites on the biomarkers of inflammation and insulin resistance in type 2 diabetes: a pilot study.

Berry fruits are rich in polyphenolic compounds (PCs) and may promote health benefits. Anthocyanin (ACN) concentrations of red raspberry (RR) (Rubus idaeus) extracts were 887.6 ± 262.8 µg g-1, consisting mainly of cyanidin-3-sophoroside (C3S) equivalents. To test the efficacy of RR in diabetes treatment, seven patients with type 2 diabetes mellitus (T2DM) were given one oral RR serving (123 g per day) for two weeks. Blood samples were drawn at the baseline (BSL) and post-feeding (PF) periods for phenolic metabolite, inflammation and insulin resistance (IR) biomarker analysis. Two urolithin conjugates, urolithin A glucuronide (Uro-A glur) and urolithin A sulphate (Uro-A sulf) were identified in the PF period in 5 of the 7 patients in nanomolar concentrations (1.6 ± 0.7-63.2 ± 31.2 nM). ACN-derived metabolites such as protocatechuic acid (PCA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were at micromolar levels and were higher during the PF period for diabetics and the levels were as follows: BSL: PCA = 0.6 ± 0.4, DOPAC = 1.2 ± 0.5; PF: PCA = 0.6 ± 0.4, DOPAC = 1.1 ± 0.6. The results revealed significant reductions in high sensitivity C-reactive protein, hsCRP (p = 0.01) and there was a downward trend in IR measured by the homeostatic model assessment of insulin resistance (HOMA-IR, p = 0.0584) in T2DM patients. DOPAC (1-100 µM) failed to stimulate insulin secretion in pancreatic ß-cells. The multiplex assay showed variations in the cytokine levels between patients, but differences were not significant. This study demonstrates a potential use of RR in the treatment of inflammation and possibly IR as well in patients with type 2 diabetes.

The Potential of Dietary Bioactive Compounds against SARS-CoV-2 and COVID-19-Induced Endothelial Dysfunction.

COVID-19 is an endothelial disease. All the major comorbidities that increase the risk for severe SARS-CoV-2 infection and severe COVID-19 including old age, obesity, diabetes, hypertension, respiratory disease, compromised immune system, coronary artery disease or heart failure are associated with dysfunctional endothelium. Genetics and environmental factors (epigenetics) are major risk factors for endothelial dysfunction. Individuals with metabolic syndrome are at increased risk for severe SARS-CoV-2 infection and poor COVID-19 outcomes and higher risk of mortality. Old age is a non-modifiable risk factor. All other risk factors are modifiable. This review also identifies dietary risk factors for endothelial dysfunction. Potential dietary preventions that address endothelial dysfunction and its sequelae may have an important role in preventing SARS-CoV-2 infection severity and are key factors for future research to address. This review presents some dietary bioactives with demonstrated efficacy against dysfunctional endothelial cells. This review also covers dietary bioactives with efficacy against SARS-CoV-2 infection. Dietary bioactive compounds that prevent endothelial dysfunction and its sequelae, especially in the gastrointestinal tract, will result in more effective prevention of SARS-CoV-2 variant infection severity and are key factors for future food research to address.

The Young Age and Plant-Based Diet Hypothesis for Low SARS-CoV-2 Infection and COVID-19 Pandemic in Sub-Saharan Africa.

Since the outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that caused the coronavirus disease-19 (COVID-19), in December 2019, the infection has spread around the globe. Some of the risk factors include social distancing, mask wearing, hand washing with soap, obesity, diabetes, hypertension, asthma, cardiovascular disease, and dysbiosis. Evidence has shown the incidence of total infection and death rates to be lower in sub-Saharan Africa when compared with North Africa, Europe and North America and many other parts of the world. The higher the metabolic syndrome rate, the higher the risk of SARS-CoV-2 infection. Africa has a lower rate of metabolic syndrome risk than many other continents. This paradox has puzzled several in the biomedical and scientific communities. Published results of research have demonstrated the exciting correlation that the combination of young age of the population coupled with their native plant-based diet has lowered their risk factors. The plant-based diet include whole grains (millet, sorghum), legumes (black-eye peas, dry beans, soybean), vegetables, potato, sweet potato, yams, squash, banana, pumpkin seeds, and moringa leaves, and lower consumption of meat. The plant-based diet results in a different gut microbiota than of most of the rest of the world. This has a significant impact on the survival rate of other populations. The "plant-based diet" results in lower rates of obesity, diabetes and dysbiosis, which could contribute to lower and less severe infections. However, these hypotheses need to be supported by more clinical and biostatistics data.

Food Processing, Dysbiosis, Gastrointestinal Inflammatory Diseases, and Antiangiogenic Functional Foods or Beverages.

Foods and beverages provide nutrients and alter the gut microbiota, resulting in eubiosis or dysbiosis. Chronic consumption of a diet that is high in saturated or trans fats, meat proteins, reducing sugars, and salt and low in fiber induces dysbiosis. Dysbiosis, loss of redox homeostasis, mast cells, hypoxia, angiogenesis, the kynurenine pathway, transglutaminase 2, and/or the Janus kinase pathway are implicated in the pathogenesis and development of inflammatory bowel disease, celiac disease, and gastrointestinal malignancy. This review discusses the effects of oxidative, carbonyl, or glycative stress-inducing dietary ingredients or food processing-derived compounds on gut microbiota and gastrointestinal epithelial and mast cells as well as on the development of associated angiogenic diseases, including key signaling pathways. The preventive or therapeutic potential and the biochemical pathways of antiangiogenic or proangiogenic foods or beverages are also described. The outcomes of the interactions between disease pathways and components of food are critical for the design of foods and beverages for healthy lives.

Cytotoxicity of juglone and thymoquinone against pancreatic cancer cells.

Juglone and thymoquinone are cytotoxic to pancreatic cancer cells. The aim of this study was to investigate, using an analysis of isobolograms, the type and degree of interactions between juglone and thymoquinone on MIA PaCa-2 pancreatic cancer cells. Cell viability was evaluated using the MTT assay. Cell death was determined by flow cytometry. The IC50 value for juglone and TQ in combination was found to be 24.75 µM, which was higher than juglone or TQ alone. Juglone alone killed Mia Paca-2 cells by ferroptosis. At concentrations where 10, 20 or 50% of cells were affected, there existed a moderate antagonistic relationship between juglone and TQ as indicated by the combination index (CI) value determined by the Compusyn software. At concentrations that affected 75% and 90% of cells, there were nearly an additive effect with CI value of 1.09249 and 0.92391, respectively. Moderate synergism was only seen at concentration where 95% of cells were affected, and the corresponding concentration of juglone and TQ at that combination was 40.90 µM and 511.19 µM, respectively.

Hyaluronic Acid-Cellulose Composites as Patches for Minimizing Bacterial Infections.

A facile method was used to synthesize biocomposites containing differing ratios of hyaluronic acid (HA) and cellulose (CEL). Based on the properties of the individual polymers, the resultant composite materials may have potentially great wound care properties. In the method outlined here, 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), a simple ionic liquid, was used as the sole solvent without chemical modifiers to dissolve the biopolymers at ratios of 1:1 and 2:1 HA to CEL. This method was completely recyclable since the ionic liquid, [Bmim][Cl], can be recovered. Results from spectroscopic measurements [Fourier transform infrared (FT-IR) and X-ray diffraction (XRD)] confirm the interaction between HA and CEL. Scanning electron microscopy (SEM) images reflect differing biopolymer ratios and the resulting impact on the texture and porosity of these composite materials. The composites exhibited high swelling capacity in various media. These composites were also drug-loaded to examine drug release properties for greater potential in combating Staphylococcus aureus infections.

Pilot Study of the Tart Cherry Juice for the Treatment of Insomnia and Investigation of Mechanisms.

BACKGROUND: Insomnia is common in the elderly and is associated with chronic disease, but use of hypnotics increases the incidence of falls. Montmorency tart cherry juice has improved insomnia by self-report questionnaire. STUDY QUESTION: Is insomnia confirmed by polysomnography and is tryptophan availability a potential mechanism for treating insomnia? STUDY DESIGN: A placebo-controlled balanced crossover study with subjects older than 50 years and insomnia were randomized to placebo (2 weeks) or cherry juice (2 weeks) (240 mL 2 times/d) separated by a 2-week washout. MEASURES AND OUTCOMES: Sleep was evaluated by polysomnography and 5 validated questionnaires. Serum indoleamine 2,3-dioxygenase (IDO), the kynurenine-to-tryptophan ratio, and prostaglandin E2 were measured. In vitro, Caco-2 cells were stimulated with interferon-gamma, and the ability of cherry juice procyanidin to inhibit IDO which degrades tryptophan and stimulates inflammation was measured. The content of procyanidin B-2 and other major anthocyanins in cherry juice were determined. RESULTS: Eleven subjects were randomized; 3 with sleep apnea were excluded and referred. The 8 completers with insomnia increased sleep time by 84 minutes on polysomnography (P = 0.0182) and sleep efficiency increased on the Pittsburgh Sleep Quality Index (P = 0.03). Other questionnaires showed no significant differences. The serum kynurenine-to-tryptophan ratio decreased, as did the level of prostaglandin E2 (both P < 0.05). In vitro, cherry juice procyanidin B-2 dose-dependently inhibited IDO. CONCLUSIONS: Cherry juice increased sleep time and sleep efficiency. Cherry juice procyanidin B-2 inhibited IDO, increased tryptophan availability, reduced inflammation, and may be partially responsible for improvement in insomnia.

Targeting MicroRNA in Cancer Using Plant-Based Proanthocyanidins.

Proanthocyanidins are oligomeric flavonoids found in plant sources, most notably in apples, cinnamon, grape skin and cocoa beans. They have been also found in substantial amounts in cranberry, black currant, green tea, black tea and peanut skins. These compounds have been recently investigated for their health benefits. Proanthocyanidins have been demonstrated to have positive effects on various metabolic disorders such as inflammation, obesity, diabetes and insulin resistance. Another upcoming area of research that has gained widespread interest is microRNA (miRNA)-based anticancer therapies. MicroRNAs are short non-coding RNA segments, which plays a crucial role in RNA silencing and post-transcriptional regulation of gene expression. Currently, miRNA based anticancer therapies are being investigated either alone or in combination with current treatment methods. In this review, we summarize the current knowledge and investigate the potential of naturally occurring proanthocyanidins in modulating miRNA expression. We will also assess the strategies and challenges of using this approach as potential cancer therapeutics.

Differential effect of 14 free fatty acids in the expression of inflammation markers on human arterial coronary cells.

Cardiovascular disease is the leading cause of death in the United States, and circulating free fatty acids (FFAs) are known risk factors associated with cardiovascular inflammation. The influence of 14 dietary FFAs (including saturated, mono- and polyunsaturated, and trans) on the expression of inflammatory markers in human coronary arterial smooth muscle (HCASM) and endothelial (HCEC) cells using a cell culture model was investigated. HCASM and HCEC cell cultures were incubated with 200 µM of each FFA for 8 or 24 h, respectively, at 37 °C in a 5% CO2 humidified incubator. Inflammatory markers were assessed by ELISA or Western blot in the supernatant or cell lysates respectively. Results showed significant differences in the expression of inflammatory markers among the fatty acid treatments and the control, with myristic and palmitic acids being identified as the most and linoleic acid as the least pro-inflammatory. This suggests that FFAs may induce low-grade inflammation in human coronary arterial cells and provides more information on mode of action.

Evolution of phenolic compounds from color and flavor problems to health benefits.

Early studies focused on the negative effects on color and flavor of foods, followed by exploration of the antioxidant properties and the associated health benefits. The growing body of evidence suggests that plant-based polyphenols may help prevent or delay the onset of a multiplicity of diseases. Newer work suggests that a variety of polyphenols can alter the expression of genes in the inflammatory pathway. Data also show that the absorption of the polyphenols is very limited. Insulin resistance and endothelial and mitochondrial dysfunction are hallmarks of the metabolic syndrome and aging and occur at the early stages of the disease. There is limited clinical evidence that certain polyphenolic metabolites by virtue of their anti-inflammatory activities can improve insulin sensitivity and endothelial and mitochondrial function, suggesting that polyphenols are good for disease prevention. The goal of this review is to summarize the evolution and emphasize the potential benefits of polyphenols.

Effect of freeze-dried berries on the development of reflux-induced esophageal adenocarcinoma.

The incidence of esophageal adenocarcinoma in humans is increasing more rapidly than any other malignancy in the United States. Animal studies have demonstrated the efficacy of freeze-dried berry supplementation on carcinogen-induced esophageal squamous cell carcinoma in rats; however, no such studies have been done in esophagoduodenal anastomosis (EDA), an animal model for reflux-induced esophageal adenocarcinoma (EAC) development. Eight-week-old male Sprague-Dawley rats were randomized into 3 groups: EDA + control diet (EDA-CD; n = 10); EDA + 2.5% black raspberry diet (EDA-BRB; n = 11) and EDA + 2.5% blueberry diet (EDA-BB; n = 12). After 2 wk of feeding the respective diets, the rats underwent EDA surgery to induce gastroesophageal reflux and then continued the diet. Measurement of feed intake suggested that all EDA-operated animals had lower feed intake starting at 10 wk after surgery and this was significant close to termination at 24 wk. There were no significant differences in either reflux esophagitis (RE), intestinal metaplasia (IM) (70% in CD, 64% in BRB, and 66% in BB; P = 0.1) or EAC incidence (30% for CD, 34% for BRB, and 25% for BB; P = 0.2) with supplementation. Berry diets did not alter COX-2 levels, but BB diet significantly reduced MnSOD levels (1.23 ± 0.2) compared to control diet (2.05 ± 0.14; P < 0.05). We conclude that a dietary supplementation of freeze-dried BRB and BB at 2.5% (w/w) was not effective in the prevention of reflux-induced esophageal adenocarcinoma in this EDA animal model.

Positive cooperative mechanistic binding of proteins at low concentrations: a comparison of poly (sodium N-undecanoyl sulfate) and sodium dodecyl sulfate.

The interactions of the negatively charged achiral molecular micelle, poly (sodium N-undecanoyl sulfate) (poly-SUS), with four different proteins using intrinsic and extrinsic fluorescence spectroscopic probes, are studied. A comparison of poly-SUS with the conventional surfactant, sodium dodecyl sulfate (SDS), and the monomeric species, SUS, is also reported. In this work, we observed that poly-SUS preferentially binds to acidic proteins, exhibiting positive cooperativity at concentrations less than 1 mM for all proteins studied. Moreover, it appears that the hydrophobic microdomain formed through polymerization of the terminal vinyl group of the monomer, SUS, is largely responsible for the superior binding capacity of poly-SUS. From these results, we conclude that the interactions of poly-SUS with the acidic proteins are predominantly hydrophobic and postulate that poly-SUS would produce superior interactions relative to SDS at low concentrations in polyacrylamide gel electrophoresis (PAGE). As predicted, use of poly-SUS allowed separation of the His-tagged tumor suppressor protein, p53, at sample buffer concentrations as low as 0.08% w/v (2.9 mM), which is 24 times lower than required for SDS in the standard reducing PAGE protocol. This work highlights the use of poly-SUS as an effective surfactant in 1D biochemical analysis.

Coupling in vitro and in vivo paradigm reveals a dose dependent inhibition of angiogenesis followed by initiation of autophagy by C6-ceramide.

The activity of N-hexanoyl-D-erythro-sphingosine, a C6-ceramide against angiogenesis was tested in vitro and in vivo. The effect of ceramide in inhibiting MCF-7 cancer cells was also determined. The aim of this study was to potentiate the effect of ceramide as anti-angiogenic compound that can regulate tumor induced angiogenesis.C6-ceramide inhibited vascular endothelial growth factor (VEGF)-induced human umbilical vein endothelial cells (HUVEC) tube formation in a dose-dependent manner within 24 hours. Ceramide at concentrations between 12.5 and 25 µM inhibited the viability of MCF-7 cells and reduced VEGF-induced cell migration in 24 hours. At 50 µM, ceramide induced MCF-7 cell death via autophagy as demonstrated by accumulation of MDC in ceramide-treated MCF-7 vacuoles. The expression of VEGF was reduced and the levels of cathepsin D in MCF-7 increased. In vivo, 50 µM ceramide caused a 40% reduction of new vessel formation in the CAM assay within 24 hours. Zebrafish exposed to 100 - 400 µM ceramide had a distinct disruption of blood vessel development at 48 hours post-fertilization. Ceramide-exposed embryos also had primary motoneurons exhibiting abnormal axonal trajectories and ectopic branching. Ceramide induced cell-death was not detected in the zebrafish assay. Collectively, these data indicate that ceramide is a potent anti-angiogenic compound and that the mechanism underlying its anti-angiogenic capabilities does not rely upon the induction of apoptosis.

Rhein inhibits angiogenesis and the viability of hormone-dependent and -independent cancer cells under normoxic or hypoxic conditions in vitro.

Hypoxia is a hallmark of solid tumors, including breast cancer, and the extent of tumor hypoxia is associated with treatment resistance and poor prognosis. Considering the limited treatment of hypoxic tumor cells and hence a poor prognosis of breast cancer, the investigation of natural products as potential chemopreventive anti-angiogenic agents is of paramount interest. Rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid), the primary anthraquinone in the roots of Cassia alata L., is a naturally occurring quinone which exhibits a variety of biologic activities including anti-cancer activity. However, the effect of rhein on endothelial or cancer cells under hypoxic conditions has never been delineated. Therefore, the aim of this study was to investigate whether rhein inhibits angiogenesis and the viability of hormone-dependent (MCF-7) or -independent (MDA-MB-435s) breast cancer cells in vitro under normoxic or hypoxic conditions. Rhein inhibited vascular endothelial growth factor (VEGF(165))-stimulated human umbilical vein endothelial cell (HUVEC) tube formation, proliferation and migration under normoxic and hypoxic conditions. In addition, rhein inhibited in vitro angiogenesis by suppressing the activation of phosphatidylinositol 3-kinase (PI3K), phosphorylated-AKT (p-AKT) and phosphorylated extracellular signal-regulated kinase (p-ERK) but showed no inhibitory effects on total AKT or ERK. Rhein dose-dependently inhibited the viability of MCF-7 and MDA-MB-435s breast cancer cells under normoxic or hypoxic conditions, and inhibited cell cycle in both cell lines. Furthermore, Western blotting demonstrated that rhein inhibited heat shock protein 90alpha (Hsp90α) activity to induce degradation of Hsp90 client proteins including nuclear factor-kappa B (NF-κB), COX-2, and HER-2. Rhein also inhibited the expression of hypoxia-inducible factor-1 alpha (HIF-1α), vascular endothelial growth factor (VEGF(165)), epidermal growth factor (EGF), and the phosphorylation of inhibitor of NF-κB (I-κB) under normoxic or hypoxic conditions. Taken together, these data indicate that rhein is a promising anti-angiogenic compound for breast cancer cell viability and growth. Therefore, further studies including in vivo and pre-clinical need to be performed.

Dietary whey protein decreases food intake and body fat in rats.

We investigated the effects of dietary whey protein on food intake, body fat, and body weight gain in rats. Adult (11-12 week) male Sprague-Dawley rats were divided into three dietary treatment groups for a 10-week study: control. Whey protein (HP-W), or high-protein content control (HP-S). Albumin was used as the basic protein source for all three diets. HP-W and HP-S diets contained an additional 24% (wt/wt) whey or isoflavone-free soy protein, respectively. Food intake, body weight, body fat, respiratory quotient (RQ), plasma cholecystokinin (CCK), glucagon like peptide-1 (GLP-1), peptide YY (PYY), and leptin were measured during and/or at the end of the study. The results showed that body fat and body weight gain were lower (P < 0.05) at the end of study in rats fed HP-W or HP-S vs. control diet. The cumulative food intake measured over the 10-week study period was lower in the HP-W vs. control and HP-S groups (P < 0.01). Further, HP-W fed rats exhibited lower N(2) free RQ values than did control and HP-S groups (P < 0.01). Plasma concentrations of total GLP-1 were higher in HP-W and HP-S vs. control group (P < 0.05), whereas plasma CCK, PYY, and leptin did not differ among the three groups. In conclusion, although dietary HP-W and HP-S each decrease body fat accumulation and body weight gain, the mechanism(s) involved appear to be different. HP-S fed rats exhibit increased fat oxidation, whereas HP-W fed rats show decreased food intake and increased fat oxidation, which may contribute to the effects of whey protein on body fat.

Inhibition of the formation of advanced glycation end products by thymoquinone.

The inhibitory activity of thymoquinone, a major quinone from black seeds (Nigella sativa) against the formation of advanced glycation end products was studied using the hemoglobin-δ-gluconolactone, human serum albumin-glucose, and the N-acetyl-glycyl-lysine methyl ester-ribose assays. A comparison was made with the inhibitory activity of aminoguanidine. The cytotoxicity of thymoquinone was studied by the release of lactate dehydrogenase from platelets and the levels of plasma thiols. At 20µM, thymoquinone inhibited 39% of hemoglobin glycation, 82% of post-Amadori glycation products, reduced methyglyoxal-mediated human serum albumin glycation by 68%, inhibited 78% of late glycation end products. Aminoguanidine at 10mM was less effective than thymoquinone. The IC50 for thymoquinone and aminoguanidine were 7.2µM and 1.25mM, respectively. Thymoquinone at 20-50µM was not toxic to platelet lactate dehydrogenase and plasma thiols. The potential of thymoquinone in food applications is discussed.

trans-resveratrol inhibits hyperglycemia-induced inflammation and connexin downregulation in retinal pigment epithelial cells.

The purpose of this study was to determine the inhibitory activity of trans-resveratrol against hyperglycemia-induced inflammation and degradation of gap junction intercellular communication in retinal pigment epithelial cells. Retinal (ARPE-19) cells were incubated with 5.5 mM glucose, 5.5 mM glucose and 10 microM resveratrol, 33 mM glucose, or 33 mM glucose and 0-10 microM trans-resveratrol at 37 degrees C and 5% CO(2) for 9 days. Cell viability was determined by the crystal violet assay. The levels of low-grade inflammation biomarkers interleukin-6 and interleukin-8 (IL-6 and IL-8), angiogenic factors, and vascular endothelial growth factor (VEGF) were determined by the enzyme-linked immunosorbent assay (ELISA). Gap junction intercellular communication (GJIC) was determined by the scrape-load/dye transfer method. The expression levels of protein kinase Cbeta (PKCbeta), connexin 43 (Cx43), transforming growth factor-beta1 (TGF-beta1), and cyclooxygenase-2 (COX-2) were determined by Western blot. Incubation of retinal cells with 10 microM trans-resveratrol in the presence of 5.5 mM glucose did not affect any of the biomarkers investigated. Incubation of ARPE-19 cells with 33 mM glucose for 9 days significantly induced the accumulation of VEGF, IL-6, IL-8, TGF-beta, and COX-2, activation of PKCbeta, and reduction of Cx43 and GJIC. Incubation of ARPE-19 cells with 33 mM glucose in the presence of 0-10 microM trans-resveratrol dose-dependently inhibited VEGF, TGF-beta1, COX-2, IL-6, and IL-8 accumulation, PKCbeta activation, and Cx43 degradation and enhanced GJIC. These data suggest that trans-resveratrol can protect the retinal pigment epithelial cells against hyperglycemia-induced low-grade inflammation and GJIC degradation.

Delivery of phytochemical thymoquinone using molecular micelle modified poly(D, L lactide-co-glycolide) (PLGA) nanoparticles.

Continuous efforts have been made in the development of potent benzoquinone-based anticancer drugs aiming for improved water solubility and reduced adverse reactions. Thymoquinone is a liposoluble benzoquinone-based phytochemical that has been shown to have remarkable antioxidant and anticancer activities. In the study reported here, thymoquinone-loaded PLGA nanoparticles were synthesized and evaluated for physico-chemical, antioxidant and anticancer properties. The nanoparticles were synthesized by an emulsion solvent evaporation method using anionic molecular micelles as emulsifiers. The system was optimized for maximum entrapment efficiency using a Box-Behnken experimental design. Optimum conditions were found for 100 mg PLGA, 15 mg TQ and 0.5% w/v poly(sodium N-undecylenyl-glycinate) (poly-SUG). In addition, other structurally related molecular micelles such as poly(sodium N-heptenyl-glycinate) (poly-SHG), poly(sodium N-undecylenyl-leucinate) (poly-SUL), and poly(sodium N-undecylenyl-valinate) (poly-SUV) were also examined as emulsifiers. All investigated molecular micelles provided excellent emulsifier properties, leading to maximum optimized TQ entrapment efficiency, and monodispersed particle sizes below 200 nm. The release of TQ from molecular micelle modified nanoparticles was investigated by dialysis and reached lower levels than the free drug. The antioxidant activity of TQ-loaded nanoparticles, indicated by IC50 (mg ml( - 1) TQ for 50% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity), was highest for poly-SUV emulsified nanoparticles (0.030 +/- 0.002 mg ml( - 1)) as compared to free TQ. In addition, it was observed that TQ-loaded nanoparticles emulsified with poly-SUV were more effective than free TQ against MDA-MB-231 cancer cell growth inhibition, presenting a cell viability of 16.0 +/- 5.6% after 96 h.