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• The pH dependence of the casein micelle was investigated using SAXS and USAXS. • SAXS profiles were analyzed using a structure model including water domains. • The size of a micelle and CCP were changed in response to changes in pH. • pH affected the voluminosity and other physical properties in a micelle. • The structure of the casein micelles varied sensitively with pH changes. Changes in milk pH significantly influence the behavior and physical properties of casein micelles; however, the effects of these changes on casein micelle structures are still unclear. The aim of this study was to elucidate the effect of changes in pH range from 5.9 to 7.1 on the structure of casein micelles in milk using small-angle X-ray scattering (SAXS) and ultra small-angle X-ray scattering (USAXS). The casein micelles formed one-dimensional aggregates. The micelle radius decreased with decreasing pH, whereas the size of the water domain increased. The distance between colloidal calcium phosphates (CCP) remained unchanged, whereas the CCP radius decreased with decreasing pH. Voluminosity, which was calculated from scattering intensities, increased at increased pH. In conclusion, the micelle structure changed significantly in response to changes in pH. Our findings help to understand the changes in the physical properties of milk at various pH levels in terms of the microscopic structure. [ABSTRACT FROM AUTHOR]

The intracellular delivery of functionally active transcription factor proteins is emerging as a promising technique for artificial regulation of cellular functions. However, in addition to the cell membrane, which acts as a barrier to macromolecules, the aggregation-favored properties of structurally flexible transcription factor proteins limit the application of this method. In-cell folding technique can be used to overcome these issues. This technique solubilizes denatured protein by reversible alkyl-disulfide cationization ( S -cationization), and simultaneously endows efficient intracellular delivery and folding to the biologically active conformation in the reducing environment of the cytosol. Because cationized protein is internalized into cells by adsorption-mediated endocytosis, endosomal escape is crucial for this technique. In this study, we utilized a sensitive luciferase reporter gene assay to quantitatively evaluate in-cell folding of the artificial transcription factor GAL4-VP16. Although the cationic moiety of S -cationized protein was slightly affected, co-transduction of amphipathic peptide Endo-PORTER dramatically improved in-cell folding efficiency. Live cell imaging of fluorescent-labeled GAL4-VP16 revealed that some of the proteins diffused into the cytosol and nucleus through co-transduction with Endo-PORTER. Real-time monitoring of light output of luciferase revealed the kinetics of in-cell folding, supporting that endosomal-release assisted by Endo-PORTER was stimulated by endosome acidification. Because this method can transduce proteins uniformly and repeatedly into living cells, S -cationized transcription factor proteins are widely applicable for the artificial regulation of cellular functions. [ABSTRACT FROM AUTHOR]

• The temperature-dependence of the casein micelle was investigated by in-situ SAXS. • SAXS profiles were analyzed using a structure model including water domains. • Inner structure of casein micelles varied sensitively with temperature changes. • The structure changes were thermoreversible. Milk is used and processed under various environmental temperature, and its physicochemical properties are also strongly affected by temperature. Therefore, it is important to reveal the structure of milk at variable temperatures. In this study, the temperature dependence of the inner structure of bovine casein micelles in the temperature range of 10–40 °C was investigated by in-situ small-angle X-ray scattering (SAXS) method. The micelle size calculated from the SAXS profiles using a micelle model including water domains was almost independent of temperature. The water domain expanded and the distance between the colloidal calcium phosphates (CCP) decreased with increasing temperature. The number of CCPs in a micelle increased, because CCPs were newly formed by the transfer of calcium and inorganic phosphate from serum into the micelle. These structural changes occurred during the cooling process. Therefore, in the temperature range of 10–40 °C, the structure of the casein micelle varied sensitively with the temperature, and these structural changes were thermoreversible in nature. [ABSTRACT FROM AUTHOR]

Previous study suggested that dietary intake of Lactobacillus plantarum 06CC2 (LP06CC2) isolated from Mongolian dairy products showed various health beneficial effects. Here, the effect of LP06CC2 on the cholesterol metabolism in mice fed a cholesterol‐loaded diet was evaluated. Cholesterol and LP06CC2 were incorporated into the AIN93G‐based diet to evaluate the effect on cholesterol metabolism in Balb/c mice. Serum and liver cholesterol levels were significantly increased in mice fed a cholesterol‐loaded diet whereas the LP06CC2 ingestion suppressed the increase of liver cholesterol. LP06CC2 suppressed the increase of the hepatic damage indices. The increase of the cecal content and fecal butyrate were observed in mice fed LP06CC2. The analysis of bile acids clearly showed that LP06CC2 increased their deconjugation indicating the decrease of bile acid absorption. The protein expression of hepatic Cyp7A1 was also suppressed by LP06CC2 in mice fed cholesterol. Finally, in vitro studies showed that LP06CC2 had the most potent ability to deconjugate bile acids using glycocholate among the tested probiotic lactic acid bacteria isolated from Mongolian dairy products. Taken together, LP06CC2 is a promising microorganism for the reduction of the cholesterol pool via modulation of bile acid deconjugation. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the effects of low-dose pioglitazone (7.5mg/day) on serum high molecular weight (HMW) adiponectin and fluid retention (estimated from hematocrit) in 14 male and 16 female patients with type 2 diabetes. All of them were being treated with sulfonylureas and had poor glycemic control. Patients were given 7.5mg/day of pioglitazone and were followed for 12 weeks at monthly intervals. In all 30 patients, HbA1c was significantly decreased after 12 weeks of treatment with pioglitazone (8.2±0.7% vs. 7.4±0.8%, P <0.0001). Serum HMW adiponectin increased markedly from 5.2 (2.4, 8.6)μg/ml at baseline to 9.8 (4.1, 12.6)μg/ml at the end of pioglitazone treatment (P <0.0001). When the changes were evaluated separately for each sex, diabetic men showed no increase of body weight or BMI after treatment, while HbA1c decreased significantly, and did Hct. Serum HMW adiponectin increased significantly after treatment. In diabetic women, neither body weight nor BMI increased after treatment with pioglitazone, as was the case for the men. HbA1c decreased significantly, and did Hct. Serum HMW adiponectin increased significantly after treatment. In conclusion, low-dose pioglitazone therapy could significantly improved glycemic control and markedly increased serum HMW adiponectin in both male and female Japanese patients with type 2 diabetes. [Copyright &y& Elsevier]