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Patients with celiac disease continue to be exposed to gluten despite efforts to maintain a gluten-free diet (GFD). Gluten exposure in those with celiac disease leads to pathological changes in the small intestine that may or may not be associated with gastrointestinal distress. While several studies have investigated a GFD, little is known about sources of gluten contamination that prevent proper maintenance of such a diet by celiac patients. In this study, we investigate common food practices that could lead to gluten cross-contact. Three different practices were examined for gluten cross-contact: gluten-free foods fried in a fryer also used for gluten containing foods, gluten-free bread toasted in a toaster also used for gluten-containing bread, and popular sandwich spreads applied with a knife used on gluten-containing bread (mayonnaise, jam, and peanut butter). We used the ALLER-TEK™ Gluten ELISA test kit and the sandwich ELISA RIDASCREEN Gliadin test kit, which is endorsed for determination of gluten content and used for the evaluation of food cross-contact. Using both kits gave the advantage of using the 401.2 antibody as well as the better established R5 antibody, providing increased confidence in our results. We found these practices resulted in small amounts of gluten cross-contact, although the majority of the results (93.6%) showed no significant cross-contact. Mayonnaise and peanut butter samples were contaminated with gluten above the limit designated by the FDA as gluten-free20 kg/mg (ppm).

In this research, we explored various immobilized enzyme support materials, including the novel nylon-6 fiber membrane (NFM), and evaluated the increase in surface area and its effect on enzyme binding potential. We also manipulated incubation and reaction conditions and assessed the subsequent effects on activity and stability of β-galactosidase, with comparisons between various solid support materials and free (dissolved) enzyme. Nylon-6 fiber membranes were created by electrospinning and were compared with other materials as solid supports for enzyme binding. The other materials included polyvinylidene fluoride 5-kDa nanofiltration dairy membranes, nylon-6 pellets, and silica glass beads. Scanning electron microscopy revealed the large surface area of NFM, which correlated with greater enzyme activity compared with the relatively flatter surfaces of the other solid support materials. Enzyme activity was measured spectrophotometrically with the color-changing substrate o-nitrophenyl-β-d-galactopyranoside. Compared with the other solid supports, NFM had greater maximum enzyme binding potential. Across pH conditions ranging from 3.5 to 6.0 (including the optimal pH of 4.0-5.0), enzyme activity was maintained on the membrane-immobilized samples, whereas free enzyme did not maintain activity. Altering the storage temperature (4, 22, and 50°C) affected enzyme stability (i.e., the ability of the enzyme to maintain activity over time) of free and polyvinylidene fluoride membrane samples. However, NFM samples maintained stability across the varying storage temperatures. Increasing the immobilization solution enzyme concentration above the maximum enzyme binding capacity had no significant effect on enzyme stability for membrane-immobilized samples; however, both had lower mean stability than free enzyme by approximately 74%. With further development, β-galactosidase immobilized on NFM or other membranes could be used in continuous processing in the dairy industry for a combination of filtration and lactose hydrolysis-creating products that are reduced in lactose and increased in sweetness, with no requirement for "added sugars" on the nutrition label and no enzyme listed as final product ingredient.

Prostate cancer is the second most commonly diagnosed cancer in men, and metastatic prostate cancer is currently incurable. Prostate cancer frequently becomes resistant to standard of care treatments, and the administration of chemotherapeutic drugs is often accompanied by toxic side effects. Combination therapy is one tool that can be used to combat therapeutic resistance and drug toxicity. Vitamin E (VE) compounds and analogs have been proposed as potential non-toxic chemotherapeutics. Here we modeled combination therapy using mixture design response surface methodology (MDRSM), a statistical technique designed to optimize mixture compositions, to determine whether combinations of three chemotherapeutic agents: &gamma, tocotrienol (&gamma, T3), &alpha, tocopherol ether acetate (&alpha, TEA), and docetaxel (DOC), would prove more effective than docetaxel alone in the treatment of human prostate cancer cells. Response surfaces were generated for cell viability, and the optimal treatment combination for reducing cell viability was calculated. We found that a combination of 20 &micro, M &gamma, T3, 30 &micro, M &alpha, TEA, and 25 nm DOC was most effective in the treatment of PC-3 cells. We also found that the combination of &gamma, T3 and &alpha, TEA with DOC decreased the amount of DOC required to reduce cell viability in PC-3 cells and ameliorated therapeutic resistance in DOC-resistant PC-3 cells.

Combining chemotherapeutics to treat malignant tumors has been shown to be effective in preventing drug resistance, tumor recurrence, and reducing tumor size. We modeled combination drug therapy in PC-3 human prostate cancer cells using mixture design response surface methodology (MDRSM), a statistical technique designed to optimize compositions that we applied in a novel manner to design combinations of chemotherapeutics. Conventional chemotherapeutics (mitoxantrone, cabazitaxel, and docetaxel) and natural bioactive compounds (resveratrol, piperlongumine, and flavopiridol) were used in 12 different combinations containing three drugs at varying concentrations. Cell viability and cell cycle data were collected and used to plot response surfaces in MDRSM that identified the most effective concentrations of each drug in combination. MDRSM allows for extrapolation of data from three or more compounds in variable ratio combinations, unlike the Chou-Talalay method. MDRSM combinations were compared with combination index data from the Chou-Talalay method and were found to coincide. We propose MDRSM as an effective tool in devising combination treatments that can improve treatment effectiveness and increase treatment personalization, because MDRSM measures effectiveness rather than synergism, potentiation, or antagonism.

Background Avenanthramides (AVN) are a relatively unstudied family of phytochemicals that could be novel chemotherapeutics. These compounds, found in oats, are non-toxic to healthy cells and have been shown to reduce viability of human colon and liver cancers in vitro. However, these studies do not elucidate a molecular mechanism for individual AVN. In this study we aim to see the effects of AVN on MDA-MB-231 breast cancer cells. Methods An MTT assay was used to determine cell viability. Staining and analysis with a flow cytometer was used to identify cell cycle progression and apoptosis. FloJo software was used to analyze the cytometric data. In all experiments, statistical significance was determined by a two-tailed t test. Results This study demonstrates that AVN-A, B, and C individually reduce viability in the MDA-MB-231 breast cancer cell line. AVN-C has the most potent decrease in tumor cell viability, decreasing viable cells to below 25% at 400 µM when compared to control after 96 h. We demonstrate that treatment with AVN-C causes DNA fragmentation and accumulation of over 90% of cells into a sub G1 cell cycle population. Further, we conclude that AVN-C treated cells activate apoptosis because 97% of treated cells stain positive for annexin V while 91% have caspase-3/7 activity, a late marker of apoptosis. Conclusions Breast cancer cells treated with AVN-C have a decrease in cell viability, an increase in the sub G1 population, and stain positive for both annexin V and caspase activity, indicating that AVN-C induces apoptosis in breast cancer cells. These compounds may be able to act as chemotherapeutics as demonstrated through future in vivo studies.

Resveratrol (RES) is a putative chemotherapeutic naturally found in grapes, peanuts, and Japanese knotweed. Previous studies demonstrate that RES modulates calcium signaling as part of its chemotherapeutic activity. In this study, we determined the chemotherapeutic activity of three RES esters that have been modified at the 4’ hydroxyl by the addition of pivalate, butyrate, and isobutyrate. All of the RES derivatives disrupted the calcium signaling in prostate cancer cells more than the parent compound, RES. Further, we demonstrate that the RES derivatives may disrupt the calcium homeostasis by activating calcium release from the endoplasmic reticulum and inhibiting plasma membrane Ca2+-ATPase. The pivalated and butyrated RES derivatives decreased cell viability significantly more than RES. Because pivalated and butyrated RES are more effective than RES at targeting calcium signaling pathways, pivalated and butyrated RES may serve as more effective chemotherapeutics., Highlights • Resveratrol (RES) derivatives increase [Ca2+]i more than RES in PC-3 cancer cells. • RES derivatives induce ER Ca2+ release to elevate [Ca2+]i. • RES derivatives inhibit plasma membrane Ca2+-ATPase to elevate [Ca2+]i. • RES derivatives decrease cell viability more than RES in PC-3 cancer cells.

Plasma membrane Ca2+-ATPase (PMCA) plays a vital role in maintaining cytosolic calcium concentration ([Ca2+]i). Given that many diseases have modified PMCA expression and activity, PMCA is an important potential target for therapeutic treatment. This study demonstrates that the non-toxic, naturally-occurring polyphenol resveratrol (RES) induces increases in [Ca2+]i via PMCA inhibition in primary dermal fibroblasts and MDA-MB-231 breast cancer cells. Our results also illustrate that RES and the fluorescent intracellular calcium indicator Fura-2, are compatible for simultaneous use, in contrast to previous studies, which indicated that RES modulates the Fura-2 fluorescence independent of calcium concentration. Because RES has been identified as a PMCA inhibitor, further studies may be conducted to develop more specific PMCA inhibitors from RES derivatives for potential therapeutic use.

Triple-negative breast cancer is a highly aggressive subtype of breast cancer. Frequently, breast cancer cells modulate their calcium signaling pathways to optimize growth. Unique calcium pathways in breast cancer cells could serve as a way to target tumorigenic cells without affecting normal tissue. Resveratrol has previously been shown to activate calcium signaling pathways. We use cell viability, single-cell calcium microscopy, and RT-PCR assays to determine the activity and mechanism of three different 4′-esterified resveratrol derivatives. We demonstrate that two of the derivatives reduce cell viability more effectively than resveratrol in MDA-MB-231 human breast cancer cells. The derivatives also activate similar pro-apoptotic calcium signaling pathways. In particular, the pivalated and butyrated resveratrol derivatives are intriguing putative chemotherapeutics because they are more effective at decreasing cell viability in vitro and inhibiting the plasma membrane Ca2+-ATPase, a protein that is often modulated in breast cancer.