Negative regulation of HDAC3 transcription by histone acetyltransferase TIP60 in colon cancer.

BACKGROUND: Colon cancer is the third most common cancer globally. The expression of histone deacetylase 3 (HDAC3) is upregulated, whereas the expression of tat interactive protein, 60 kDa (TIP60) is downregulated in colon cancer. However, the relationship between HDAC3 and TIP60 in colon cancer has not been clearly elucidated. OBJECTIVE: We investigated whether TIP60 could regulate the expression of HDAC3 and suppress colon cancer cell proliferation. METHODS: RNA sequencing data (GSE108834) showed that HDAC3 expression was regulated by TIP60. Subsequently, we generated TIP60-knockdown HCT116 cells and examined the expression of HDAC3 by western blotting and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). We examined the expression pattern of HDAC3 in various cancers using publicly available datasets. The promoter activity of HDAC3 was validated using a dual-luciferase assay, and transcription factors binding to HDAC3 were identified using GeneCards and Promo databases, followed by validation using chromatin immunoprecipitation-quantitative polymerase chain reaction. Cell proliferation and apoptosis were assessed using colony formation assays and fluorescence-activated cell sorting analysis of HCT116 cell lines. RESULTS: In response to TIP60 knockdown, the expression level and promoter activity of HDAC3 increased. Conversely, when HDAC3 was downregulated by overexpression of TIP60, proliferation of HCT116 cells was inhibited and apoptosis was promoted. CONCLUSION: TIP60 plays a crucial role in the regulation of HDAC3 transcription, thereby influencing cell proliferation and apoptosis in colon cancer. Consequently, TIP60 may function as a tumor suppressor by inhibiting HDAC3 expression in colon cancer cells.

Evaluation of Physicochemical Changes in Hard-Boiled Eggs Stored at Different Temperatures.

Eggs that have been hard-boiled are frequently used as ready-to-eat food. Refrigerated and frozen storage of hard-boiled eggs causes issues, such as customer rejection owing to textural changes. The objective of this research is to ascertain how storage temperature affects hard-boiled eggs' alteration in texture over time. Medium-sized brown shell eggs were acquired from a local market, boiled at 100°C for 15 min, and then stored at room temperature (25°C), refrigeration (4°C), and freezing (-18°C) conditions for 0, 12, 24, and 48 h. Fourier transform infrared spectroscopy (FTIR), texture profile, visual observation using a gemological microscope, free amino acid content, and color were measured. Freezing had a substantial impact on the eggs' hardness, gumminess, chewiness, and cohesiveness (p<0.05). The FTIR spectrums confirmed the textural changes in bonds of amide A (3,271 cm-1), amide I (1,626.2 cm-1), amide II (1,539.0 cm-1), C=O stretch of COO- (1,397 cm-1), asymmetric PO2- stretch (1,240 cm-1). Microscopic images confirmed structural changes in eggs stored at -18°C. The free amino acid content was lower in fresh and frozen eggs than in the rest (p<0.05). However, there was no discernible variation in the egg white's color when eggs were kept at 4°C (p>0.05). Salmonella spp. was found exclusively in eggs kept at room temperature. In conclusion, hard-boiled eggs did not exhibit structural or chemical changes when stored at 4°C for up to 48 h compared to freezing and room temperature conditions.

Evaluation of Meat from Native Chickens: Analysis of Biochemical Components, Fatty Acids, Antioxidant Dipeptides, and Microstructure at Two Slaughter Ages.

This study examined biochemical components, fatty acids, antioxidant dipeptides, and muscle fiber density of breast and thigh muscles from Korean new native chicken strains (A and B) at two slaughter ages, compared with white semi-broiler (W) or broilers. The pH values were different by chicken breed. The new native strains had the lowest fat content in the breast at 12 wk (p<0.05). Regardless of the muscles, A and B at 12 wk had higher levels of arachidonic acid (ARA; C20:4), docosahexaenoic acid (DHA; C22:6), and nervonic acid (C24:1) than broilers (p<0.05). A similar result was observed for the polyunsaturated fatty acids (PUFAs) and polyunsaturated and saturated fatty acids ratio (P/S) content in the breast. Irrespective of the muscles, A and B enriched with omega-3 fatty acids had a lower ω-6/ω-3 PUFA ratio than broilers (p<0.05) at 12 wk. Of the antioxidant di-peptides, the anserine contents were highest in A and B than in the W or broilers (p<0.05), regardless of the muscles and slaughter ages. Furthermore, the breast meat from A and B contained a higher muscle fiber density for both slaughter ages than the W and broilers (p<0.05). Based on these findings, even if the commercial birds (broilers or W) are raised under the similar environmental conditions as A and B, the new native chicken strains have distinct meat quality attributes, particularly higher ARA and DHA levels, lower ω-6/ω-3 PUFA ratio, and higher anserine contents.

Antioxidant Properties and Physicochemical Attributes of Meat from Berkshire Finishing Pigs Supplemented with Rubus coreanus By-Product.

A 60-d feeding trial was conducted to evaluate the effects of diets supplemented with two concentrations (0% and 0.3%) of black raspberry (Rubus coreanus Miquel) fruit by-product (RCFB) on the physicochemical characteristics, oxidative stability, antioxidant capacity, antioxidant enzyme activity, and fatty acid profile of M. longissimus dorsi (LL) porcine muscle from Berkshire finishing pigs meat. Results revealed that regardless of the sex, diets supplemented with 0.3% RCFB reduced (p<0.05) the thiobarbituric acid reactive substances (TBARS) expressed as malonaldehyde (MDA) content effectively. A higher antioxidant capacity [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity] was found (p<0.05) in response to feeding supplemented with 0.3% RCBF for male or female pigs. Moreover, 0.3% RCFB dietary feed increased (p<0.05) the glutathione peroxidase enzyme activities (GPX1) in blood plasma for male or female pigs. However, no influences were observed (p>0.05) on meat color, WHC, shear force, and fatty acid contents while fed diet supplemented with 0% or 0.3% RCFB for male or female pigs. Overall, this study suggests that a diet supplemented with 0.3% RCFB may beneficially affect owing to better oxidative stability, higher antioxidant capacity, and antioxidant enzyme activity (blood plasma) in pigs which could be a promising natural antioxidant without affecting meat quality traits.

Physicochemical and microbial characteristics of longissimus lumborum and biceps femoris muscles in Korean native black goat with wet-aging time.

This study examined the effects of different wet-aging times on the physicochemical characteristics and microbial profile of longissimus lumborum (LL) and biceps femoris (BF) muscles from Korean native black goat (KNBG) meat. The water holding capacity (WHC), pH, cooking loss, shear force, meat color, free amino acid, total bacteria, and coliform count of KNGB meat were analyzed at 0, 5, 10, and 15 days of wet-aging at 4°C under vacuum packaging. The results showed that different wet-aging times led to significant pH variations between the muscles throughout the aging period. The wet-aging time did not affect the WHC and cooking loss in meat from the LL muscle. In the BF muscle, however, meat wet-aged for five days had a significantly higher WHC and less cooking loss than meat aged for 0, 10, and 15 days. The meat from the LL muscle wet-aged for five days produced tenderer meat (low shear force value) than the unaged meat (p < 0.05). Moreover, the color was similar in the LL muscle regardless of the number of aging days. In the BF muscle, the redness (a*) was higher in the meat wet-aged for 15 days compared to that aged for 0, 5, and 10 days (p < 0.05). Regardless of the muscles, an increase in wet-aging time led to an increase in the total free amino acids contents in both muscles (p < 0.05). On the other hand, the tasty/bitter amino acid ratio was significantly higher for five days of wet-aged meat than 10 and 15 days of aging from the BF muscle. In addition, regardless of the muscles, the total bacteria and coliform counts were significantly lower for five days of wet-aged meat than 10 and 15 days of aging (p < 0.05). Therefore, chevon wet-aged for five days is an optimal aging period under vacuum packaging that fortifies meat quality with a minimal microbial negative defect.

Comparative Meat Qualities of Boston Butt Muscles (M. subscapularis) from Different Pig Breeds Available in Korean Market.

This study aimed to determine the effects of breed on meat quality characteristics of porcine Boston butt muscles (M. subscapularis) from three different pig breeds: Landrace×Yorkshire×Duroc (LYD), Berkshire, and Ibérico available in Korean market. Ibérico showed significantly higher fat content, yellowness (CIE b*), cooking loss, and lower shear force values than LYD and Berkshire. Moreover, the contents of oleic acid (18:1) and palmitic acid (16:0) were significantly higher in Ibérico breed, but stearic acid (18:0) was higher in LYD. As linoleic acid (18:2) and arachidonic acid (20:4) were higher in Berkshire sows as compared to the other breeds, atherogenicity and thrombogenicity indexes were significantly lower in Berkshire sow. Ibérico had lower the ω-6/ω-3 fatty acids ratio, and higher taurine and free amino acids compared with the others. Ibérico also showed significantly greater lipid oxidation, lower antioxidant capacity, and higher hypoxanthine contents, whereas the Berkshire had higher inosine-5'-monophosphate and lower K-index value as compared to the Ibérico. The breed did not impart any significant effect on the size and density of muscle fibers. Thus, quality characteristics of Boston butt varied from breed to breed, and certain consumer preferences for Ibérico can be explained, in part, by the unique quality characteristics imparted by higher contents of intramuscular fat, oleic acid, and free amino acids.

Comparison of Functional Compounds and Micronutrients of Chicken Breast Meat by Breeds.

The concentrations of functional compounds and micronutrients of chicken breast from native chickens were compared with those from broiler. Totally 200 male chicks from a commercial native chicken (HH) and three newly bred native chicken strains (2A, 2C, and 2D) were reared for about 2 kg of final live weight up to 12 wk. After slaughtered, antioxidant dipeptides, reducing sugar, free amino acids, vitamins, and minerals of the breast muscles were analyzed with those from broilers with similar live weight. Mostly native chicken strains had higher contents of carnosine, anserine, and reducing sugar than the broiler. Especially HH implied the highest values of carnosine and anserine, and 2C did the highest of reducing sugar (p<0.05). Vitamin A contents between native chickens and broiler were not significantly different (p>0.05). The contents of α-tocopherol were significantly higher in 2C than those of HH or broiler (p<0.05). Native chicken strains contained lower cholesterol levels than the broiler. Broiler had higher contents of P, Mg, and Na than native chickens (p<0.05), but it had lower content of Cu than HH or 2A. The savory free amino acids including glutamic acid was highest in 2A than the other native chickens and broiler (p<0.05). This study confirms that certain new strains of native chickens be a good source in terms of functional compounds and micronutrients which can be attractive health promoting nutritional quality factors.

Combined Effect of Aging and Irradiation on Physicochemical Quality of Pork Shoulder.

The effect of combined electron-beam irradiation and aging temperature of pork on microbiological and physicochemical properties was investigated. The samples from pork shoulder were irradiated with 0 or 2 kGy, vacuum-packaged, and assigned randomly to an aging temperature (2°C, 10°C, or 25°C) during 8 d. On 4 d of aging at 25°C, total aerobic bacteria of non-irradiated ones reached 7 Log CFU/g which is no salable levels. Shear force values of irradiated meat after aging for 2 and 4 d at 25°C was lower than those aged at 2°C. Irradiated samples at 2°C had lower cooking loss after 2 and 8 d of aging, compared with other aging temperatures. Irradiation did not accelerate 2-thiobarbituric acid reactive substance (TBARS) value when aged up to 4 d. Irradiated samples aged at 10°C and 25°C for 8 d scored significantly higher TBARS values. With an increased aging period, a* and b* in irradiated samples at 2°C slightly increased, but irradiation caused negligible changes in meat color. The highest contents of a desirable nucleotide flavor compounds (inosine-5-phosphate) were observed in pork at 2°C when aged for 4 and 8 d, while the lowest contents were observed at 25°C. Aging in irradiated pork for 8 d at 2°C resulted in optimal condition with improved meat quality and minimal microbiologically negative defect.

Facile fabrication of high-efficiency near-infrared absorption film with tungsten bronze nanoparticle dense layer.

An excellent transparent film with effective absorption property in near-infrared (NIR) region based on cesium-doped tungsten oxide nanoparticles was fabricated using a facile double layer coating method via the theoretical considerations. The optical performance was evaluated; the double layer-coated film exhibited 10% transmittance at 1,000 nm in the NIR region and over 80% transmittance at 550 nm in the visible region. To optimize the selectivity, the optical spectrum of this film was correlated with a theoretical model by combining the contributions of the Mie-Gans absorption-based localized surface plasmon resonance and reflections by the interfaces of the heterogeneous layers and the nanoparticles in the film. Through comparison of the composite and double layer coating method, the difference of the nanoscale distances between nanoparticles in each layer was significantly revealed. It is worth noting that the nanodistance between the nanoparticles decreased in the double layer film, which enhanced the optical properties of the film, yielding a haze value of 1% or less without any additional process. These results are very attractive for the nanocomposite coating process, which would lead to industrial fields of NIR shielding and thermo-medical applications. PACS: 78.67.Sc; 78.67.Bf; 81.15.-z.