Topical hyaluronan alone promotes corneal epithelial cell migration whereas combination with benzalkonium chloride impairs epithelial wound healing.

Purpose: To evaluate the effects of topical hyaluronan (HA) on corneal epithelial wound healing when administered with or without benzalkonium chloride (BAC).Methods: A cultured human corneal epithelial cell line (HCE-T) was subjected to in vitro scratch assays and in situ epithelial migration was evaluated in organ-cultured rabbit corneas. The corneal epithelium of C57BL/6J mice was also evaluated to determine in vivo wound healing. An in vivo imaging system was also used to evaluate the effects of HA on eye drop retention on the ocular surface.Results: The findings revealed the promotion of HCE-T migration, in situ rabbit corneal epithelial migration, and in vivo wound healing in mouse corneal epithelium by HA. Pre-treatment with HA also protected against delayed epithelial wound healing in BAC in vitro. However, pre-treatment with 3 mg/mL HA did not show a protective effect against BAC in vivo, but instead delayed epithelial wound healing and increased detection of cleaved caspase-3. This suggested that HA promotes the retention of BAC on the ocular surface. The instilled HA was retained after 15 min, at a significantly higher rate than for phosphate-buffered saline.Conclusions: The combination of HA and BAC impaired wound healing in the corneal epithelium.

Minimal effective dose of lactic-fermented egg white on visceral fat in Japanese men: a double-blind parallel-armed pilot study.

BACKGROUND: We previously reported that the consumption of 8 g of protein per day in the form of lactic-fermented egg white (LAFEW) improves visceral fat obesity. In this study, we investigated the minimum effective intake of LAFEW for visceral fat reduction in the Japanese males with mild obesity. METHODS: Twenty-two Japanese adult males with a Body mass index (BMI) ≥24 and a waist circumference ≥ 85 cm were included in this study. The subjects were divided into three groups, that is, control group, LAFEW 6 g group, and LAFEW 8 g group. The LAFEW 6 and 8 g groups consumed 6 and 8 g, respectively, of egg white protein (EWP) in a drink at breakfast for 8 weeks, whereas the control group consumed a drink containing 8 g of milk whey protein. Body weight, body fat percentage, abdominal circumference, and visceral fat (VF) area around the navel were measured at 0 and 8 weeks after initiating the consumption. RESULTS: No changes in body weight or body fat percentage were observed in any of the groups. No significant differences between the pre- and posttreatment measurements were found in the VF area around the navel in the control group and the LAFEW 6 g group. In the LAFEW 8 g group, the VF area had decreased significantly after 8 weeks of consumption, when compared to that before consumption, and the average observed decrease (Δcm2) was 13.2 ± 4.7 cm2. Among the subjects with an initial BMI > 25, the VF area was significantly smaller in the LAFEW 8 group, when compared to the week 0 values and those in the control group. Visceral fat/subcutaneous fat values in the LAFEW 8 group were also significantly smaller than those in the control group or at week 0. CONCLUSION: The results suggested that the minimum effective intake of EWP in the LAFEW to reduce the VF area in the Japanese men is 8 g. TRIAL REGISTRATION: This clinical trial was retrospectively registered with the University hospital Medical Information Network (UMIN) Center, ( UMIN000031681 ; registered on 12/03/2018).

Egg white hydrolysate improves fatigue due to short-term swimming load test in mice.

We studied the effect of egg white hydrolysate (EWH) on swimming endurance in mice. 7-week-old male ddY mice (28-30 g) were divided into three groups and fed an AIN-93G diet supplemented with casein (n = 8), EWH (n = 7), or egg white protein (EWP, n = 8) for 14 days. From day 11, the mice underwent a swimming test daily with a weight load equivalent to 10% of their body weight, and the lengths of time they swam were recorded. Blood was sampled for testing on the last day of the study. We observed that increases in the swimming duration through day 14 were significantly greater in the EWH group than in the casein group (p = 0.049). As a factor underlying this, the hexanoyl-lysine level in blood was confirmed to be decreased in the former group (p = 0.013). These findings indicate that consumption of EWH extended the swimming duration and suggest the mechanistic involvement of an antifatigue effect mediated by its antioxidant activity.

Lactic-fermented egg white improves visceral fat obesity in Japanese subjects-double-blind, placebo-controlled study.

BACKGROUND: It was reported that egg white protein (EWP) reduced body fat in rats. We developed a lactic-fermented egg white (LE) that facilitates the consumption of egg whites by fermenting them with lactobacillus, and were able to study their intake in humans. In this double-blind, placebo-controlled design, we evaluated the effect of LE on visceral fat area (VFA). METHODS: Participants included 37 adult males and females aged ≥40 years (VFA at navel ≥100 cm2). They were divided into two groups: the control group and the LE group. The control and LE groups consumed drinks containing whey and LE, respectively, for 12 weeks (providing 8 g protein/day). VFA was measured at baseline and at week 12 of intake. Abdominal girth was measured at baseline and at weeks 6 and 12. RESULTS: LE intake decreased VFA significantly compared with baseline (-8.89 cm2, p < 0.05), and VFA was significantly lower than that in the control group (+1.71 cm2, p < 0.05). The LE group showed significant improvement in the ratio of visceral to subcutaneous fat area compared with baseline and the control group (p < 0.05). CONCLUSIONS: The results demonstrated that LE reduces VFA and improves the ratio of visceral to subcutaneous fat area. As other measurement items were not influenced, we concluded that LE improves visceral fat obesity. TRIAL REGISTRATION: This clinical trial was retrospectively registered with the University hospital Medical Information Network (UMIN) Center, ( UMIN000026949 ; registered on 11/04/2017; http://www.umin.ac.jp /).

Dietary egg-white protein increases body protein mass and reduces body fat mass through an acceleration of hepatic ß-oxidation in rats.

Egg-white protein (EWP) is known to reduce lymphatic TAG transport in rats. In this study, we investigated the effects of dietary EWP on body fat mass. Male rats, 4 weeks old, were fed diets containing either 20 % EWP or casein for 28 d. Carcass protein levels and gastrocnemius leg muscle weights in the EWP group were significantly higher than those in the casein group. In addition, carcass TAG levels and abdominal fat weights in the EWP group were significantly lower than those in the casein group; adipocyte size in abdominal fat in the EWP group was smaller than that in the casein group. To identify the involvement of dietary fat levels in the rats, one of two fat levels (5 or 10 %) was added to their diet along with the different protein sources (EWP and casein). Abdominal fat weight and serum and hepatic TAG levels were significantly lower in the EWP group than in the casein group. Moreover, significantly higher values of enzymatic activity related to ß-oxidation in the liver were observed in the EWP group compared with the casein group. Finally, abdominal fat weight reduction in the EWP group with the 10 % fat diet was lower than that in the EWP group with the 5 % fat diet. In conclusion, our results indicate that, in addition to the inhibition of dietary TAG absorption reported previously, dietary EWP reduces body fat mass in rats through an increase of body protein mass and the acceleration of ß-oxidation in the liver.

Lactic-fermented egg white reduced serum cholesterol concentrations in mildly hypercholesterolemic Japanese men: a double-blind, parallel-arm design.

BACKGROUND: Lactic-fermented egg white (LE), produced by lactic acid fermentation of egg white, is an easy-to-consume form of egg white. Here we assessed the effect of daily consumption of LE for 8 weeks on serum total cholesterol (TC) levels. METHODS: The study followed a double-blind, parallel-arm design and included 88 adult men with mild hypercholesterolemia (mean ± standard error) serum TC levels, 229 ± 1.6 mg/dL; range, 204-259 mg/dL). The subjects were randomly divided into three groups, which consumed LE containing 4, 6, or 8 g of protein daily for 8 weeks. Blood samples were collected before starting LE consumption (baseline) and at 4 and 8 weeks to measure serum TC and low-density lipoprotein cholesterol (LDL-C) levels. RESULTS: After 8 weeks of consumption, serum TC levels in the 8 g group decreased by 11.0 ± 3.7 mg/dL, a significant decrease compared to baseline (p < 0.05) and a significantly greater decrease than for the 4 g group (3.1 ± 3.4 mg/dL; p < 0.05). Serum LDL-C levels in the 8 g group decreased by 13.7 ± 3.1 mg/dL, again a significant decrease compared with baseline (p < 0.05) and a significantly greater decrease than that for the 4 g group (2.1 ± 2.9 mg/dL; p < 0.05). CONCLUSION: Consumption of LE for 8 weeks at a daily dose of 8 g of proteins reduced serum TC and LDL-C levels in men with mild hypercholesterolemia, suggesting this may be effective in helping to prevent arteriosclerotic diseases. TRIAL REGISTRATION: This clinical trial was retrospectively registered with the Japan Medical Association Center for Clinical Trials, (JMA-IIA00279; registered on 13/03/2017; https://dbcentre3.jmacct.med.or.jp/JMACTR/App/JMACTRE02_04/JMACTRE02_04.aspx?kbn=3&seqno=6530 ).

Heating Has No Effect on the Net Protein Utilisation from Egg Whites in Rats.

Egg whites (EW) are a good source of protein; however, they are typically heated prior to consumption. Therefore, we investigated the effects of different heating conditions on the protein utilisation rate of EW. Male Sprague-Dawley rats (n = 36, 198 ± 1 g) were divided into six groups and fed American Institute of Nutrition-76 chow containing unheated EW, soft-boiled EW, boiled EW, milk whey protein, soybean protein, or no protein over a 10-day period using pair-feeding. Urine and faeces were sampled daily beginning on day 5 to measure nitrogen content and the net protein utilisation (NPU) rate. The soybean protein group had a significantly lower level of food intake and was thus excluded from subsequent analyses. The NPU value was similar among the unheated, soft-boiled, and boiled EW groups (97.5 ± 0.4, 96.5 ± 0.1, and 96.5 ± 0.7, resp.). The EW group values were significantly higher than the whey group values (90.5 ± 1.0). These results show that EW serve as a good source of protein, irrespective of heating.

Heat-Denatured Lysozyme Inactivates Murine Norovirus as a Surrogate Human Norovirus.

Human norovirus infects humans through the consumption of contaminated food, contact with the excrement or vomit of an infected person, and through airborne droplets that scatter the virus through the air. Being highly infectious and highly viable in the environment, inactivation of the norovirus requires a highly effective inactivating agent. In this study, we have discovered the thermal denaturing capacity of a lysozyme with known antimicrobial activity against gram-positive bacteria, as well as its inactivating effect on murine norovirus. This study is the first report on the norovirus-inactivating effects of a thermally denatured lysozyme. We observed that lysozymes heat-treated for 40 min at 100 °C caused a 4.5 log reduction in infectivity of norovirus. Transmission electron microscope analysis showed that virus particles exposed to thermally denatured lysozymes were expanded, compared to the virus before exposure. The amino acid sequence of the lysozyme was divided into three sections and the peptides of each artificially synthesised, in order to determine the region responsible for the inactivating effect. These results suggest that thermal denaturation of the lysozyme changes the protein structure, activating the region responsible for imparting an inactivating effect against the virus.

No influence of exogenous hyaluronan on the behavior of human cancer cells or endothelial cell capillary formation.

UNLABELLED: Hyaluronan (HA), a type of glycosaminoglycan used to construct the extracellular matrix, is involved in the proliferation and motility of cells, including cancer cells. The aim of this study was to determine whether exogenous HA has an influence on cancer in vitro and in vivo. High-molecular-weight HA (900 kDa) and low-molecular-weight HA (10 kDa) were added to several types of cancer cell lines in vitro, and proliferation and invasion were assessed. The effect of HA on capillary formation by human umbilical vein endothelial cells was also analyzed. The results showed that both types of HA had no apparent effect on cellular proliferation, invasion, or capillary formation. In an animal study, the 2 types of HA were orally administered to tumor-bearing mice at a dosage of 200 mg/kg/d for 4 wk. Analysis using an in vivo imaging system revealed that tumor proliferation and metastasis were not greatly altered by HA administration. Furthermore, CD31 immunohistochemical staining revealed no obvious change in tumor microvessels. Taken together, these results demonstrate that exogenously administered HA has little effect on cancer. This study may support the safety of various forms of HA administration, including oral intake. PRACTICAL APPLICATION: Orally administered hyaluronan was recently found to have beneficial effects. However, the effect of exogenous hyaluronan on cancer remains unclear. Our findings support the safety of orally administered hyaluronan and its use as a functional food ingredient.

Growth modeling of Listeria monocytogenes in pasteurized liquid egg.

The growth kinetics of Listeria monocytogenes and natural flora in commercially produced pasteurized liquid egg was examined at 4.1 to 19.4°C, and a growth simulation model that can estimate the range of the number of L. monocytogenes bacteria was developed. The experimental kinetic data were fitted to the Baranyi model, and growth parameters, such as maximum specific growth rate (µ(max)), maximum population density (N(max)), and lag time (λ), were estimated. As a result of estimating these parameters, we found that L. monocytogenes can grow without spoilage below 12.2°C, and we then focused on storage temperatures below 12.2°C in developing our secondary models. The temperature dependency of the µ(max) was described by Ratkowsky's square root model. The N(max) of L. monocytogenes was modeled as a function of temperature, because the N(max) of L. monocytogenes decreased as storage temperature increased. A tertiary model of L. monocytogenes was developed using the Baranyi model and µ(max) and N(max) secondary models. The ranges of the numbers of L. monocytogenes bacteria were simulated using Monte Carlo simulations with an assumption that these parameters have variations that follow a normal distribution. Predictive simulations under both constant and fluctuating temperature conditions demonstrated a high accuracy, represented by root mean square errors of 0.44 and 0.34, respectively. The predicted ranges also seemed to show a reasonably good estimation, with 55.8 and 51.5% of observed values falling into the prediction range of the 25th to 75th percentile, respectively. These results suggest that the model developed here can be used to estimate the kinetics and range of L. monocytogenes growth in pasteurized liquid egg under refrigerated temperature.

Mayonnaise contributes to increasing postprandial serum ß-carotene concentration through the emulsifying property of egg yolk in rats and humans.

We performed in vitro, animal, and human studies to clarify the effect of mayonnaise on ß-carotene intake and its mechanism. In an artificial gastric juice model, we examined the transfer of ß-carotene from grated carrot to mayonnaise or vegetable oil. Mayonnaise was more easily dispersed in artificial gastric juice than vegetable oil. The ß-carotene concentration was greater in mayonnaise than vegetable oil. In rats, the postprandial serum ß-carotene concentration in the mayonnaise group (ß-carotene with mayonnaise) was higher than that in the control (ß-carotene only) and vegetable oil (ß-carotene with vegetable oil) groups. Continuous feeding of dietary ß-carotene (14 d), employing mayonnaise or egg yolk, resulted in an increased accumulation of ß-carotene in the liver. In a human study, diets were provided in the form of (1) carrot as a control (CON), (2) carrot juice (JU), (3) carrot with oil (OIL) and (4) carrot with mayonnaise (MS). Following collection of fasting blood samples, nine adult males consumed one of the four diets in random order. Fasting and postprandial changes in serum ß-carotene were assessed at 2, 3, 4, 6 and 8 h following ingestion of each diet. The incremental areas under the curves of serum ß-carotene concentration were higher following MS than following both CON and JU. In conclusion, we suggest that mayonnaise contributes to raising the serum ß-carotene concentration when consumed with carrots rich in ß-carotene, and that its mechanism is related to the emulsifying property of the egg yolk contained in mayonnaise.

[In vitro evaluation of allergenicity of dried food powders manufactured for food provocation test].

Food provocation test (FPT) is one of important diagnostic methods for food allergy, but no standard antigens for FPT have yet been developed. In this study, dried powders were manufactured from five kinds of foods (cow's milk, hen egg, chicken, soybean and wheat) by spray-drying or freeze-drying and examined in vitro for their usefulness as antigens for FPT. In SDS-PAGE, the migration pattern of the extract from each powder was the same as or closely similar to that of the extract from its material. When analyzed by ELISA, a good correlation (r=0.853-0.978) in the reactivity with sera from food-allergic patients was observed between the extracts from each powder and its material. Moreover, in cow's milk, hen egg and soybean, almost the same ELISA inhibition curves were drawn, regardless of whether the extracts from each powder and its material were used as immobilized antigens or inhibitors. These results demonstrated that each powder contains the same allergens as its material at almost the same levels, being useful as an antigen for FPT. Favorably, the powders were found to be stored without significant changes in IgE reactivity at -20 degrees C or 5 degrees C for more than 18 months, although their storage at room temperature was suggested to be avoided.