Influence of modified atmosphere packaging on protein oxidation, calpain activation and desmin degradation of beef muscles.

BACKGROUND: Protein oxidation is widespread in biochemical systems. The objective of the study was to investigate the differences in protein oxidation, µ-calpain activity, desmin proteolysis and protein solubility of beef psoas major (PM) and semi-membranosus (SM) muscles under three packaging systems during postmortem ageing. At 24 h postmortem, beef muscles were packaged respectively in air-permeable film overwrap (AP), vacuum pack (VP) or modified atmosphere (MAP, 80% O2 + 20% CO2 ), and then displayed for 10 days at 4 °C. RESULTS: Carbonyl group values and thiol group content were significantly influenced by packaging type and storage time. The SM muscles from AP and MAP showed greater µ-calpain activity compared to VP. Desmin of PM and SM from AP and MAP samples showed decreased proteolysis compared with VP. CONCLUSION: The results suggested that the inhibition of µ-calpain activity of beef samples from AP and MAP could be closely associated with protein oxidation which further lowered the level of desmin degradation compared to VP. © 2017 Society of Chemical Industry.

Assessment of ADMA, estradiol, and progesterone in severe preeclampsia.

BACKGROUND: Decreased nitrous oxide (NO) levels are crucial factors in severe preeclampsia (sPE), and asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of NO synthetase. Steroid hormones are closely related to the vascular endothelium. This study determined the levels of and correlations between ADMA, estradiol (E2), and progesterone (Pg) in sPE to investigate the roles of these factors in this disease. METHODS: Sixty-two sPE patients (sPE group) were divided into the sPE1 subgroup (28(+1)-32(+0) weeks of pregnancy), the sPE2 subgroup (32(+1)-36(+0) weeks), and the sPE3 subgroup (36(+1)-40(+0) weeks) and 75 normal pregnant women (NC group) were divided into the NC1 subgroup (28(+1)-32(+0) weeks of gestation), the NC2 subgroup (32(+1)-36(+0) weeks), and the NC3 subgroup (36(+1)-40(+0) weeks). Serum and placental ADMA levels were measured by enzyme-linked immunosorbent assay (ELISA), and serum E2 and Pg concentrations were determined by the chemilumineseent immunoassay (CLIA). RESULTS: ADMA concentrations in both the placenta and the maternal serum were significantly higher in the sPE group (p < 0.05). Higher ADMA contents were observed in the placenta relative to the maternal serum (p < 0.05). Serum E2 levels were significantly lower in the sPE group (p < 0.05). For Pg, the only significant difference was observed between the sPE1 and NC1 subgroups (p < 0.05). The Pg/E2 ratios in the sPE groups were significantly higher, with a significant high positive correlation between Pg/E2 ratios and serum ADMA levels. CONCLUSION: Increased serum levels of ADMA in sPE may result from increased secretion from the placenta, and the increased Pg/E2 ratio may play a role in the development of sPE by aggravating ADMA.

Short-Chain Fatty Acids Ameliorate Depressive-like Behaviors of High Fructose-Fed Mice by Rescuing Hippocampal Neurogenesis Decline and Blood-Brain Barrier Damage.

Excessive fructose intake is associated with the increased risk of mental illness, such as depression, but the underlying mechanisms are poorly understood. Our previous study found that high fructose diet (FruD)-fed mice exhibited neuroinflammation, hippocampal neurogenesis decline and blood-brain barrier (BBB) damage, accompanied by the reduction of gut microbiome-derived short-chain fatty acids (SCFAs). Here, we found that chronic stress aggravated these pathological changes and promoted the development of depressive-like behaviors in FruD mice. In detail, the decreased number of newborn neurons, mature neurons and neural stem cells (NSCs) in the hippocampus of FruD mice was worsened by chronic stress. Furthermore, chronic stress exacerbated the damage of BBB integrity with the decreased expression of zonula occludens-1 (ZO-1), claudin-5 and occludin in brain vasculature, overactivated microglia and increased neuroinflammation in FruD mice. These results suggest that high fructose intake combined with chronic stress leads to cumulative negative effects that promote the development of depressive-like behaviors in mice. Of note, SCFAs could rescue hippocampal neurogenesis decline, improve BBB damage and suppress microglia activation and neuroinflammation, thereby ameliorate depressive-like behaviors of FruD mice exposed to chronic stress. These results could be used to develop dietary interventions to prevent depression.

Maillard reaction in protein - polysaccharide coacervated microcapsules and its effects on microcapsule properties.

The occurrence of Maillard reaction in protein - polysaccharide coacervated microcapsules and its effects on microcapsule properties were investigated. Vitamin E microcapsules were prepared by soybean protein isolate - chitosan coacervation at 50 °C, 70 °C, or 90 °C for 12 h in the presence of maltose. Chromatic and furosine measurements revealed that Maillard reaction occurred in the microcapsules and was favored by high incubation temperatures. The three coacervation temperatures did not destroy the microcapsule structure, but improved the microencapsulation efficiency and microencapsulation yield instead. The microcapsules exhibited decreased aggregation and the increased absolute zeta potential and particle size were believed contribute to this improvement. Stability analysis demonstrated that the microcapsules possessed enhanced resistance to dissolution in water and improved storage stability than control microcapsules. It is concluded that coacervation at a temperature high enough to initiate Maillard reaction is a promising way to improve the physiochemical properties of protein - polysaccharide coacervated microcapsules.

Downregulation of lncRNA TUBA4B is Associated with Poor Prognosis for Epithelial Ovarian Cancer.

A host of studies have revealed that long non-coding RNAs (lncRNAs) are critically involved in the development and progression of epithelial ovarian cancer. LncRNA TUBA4B is recently identified to be a critical mediator in non-small cell lung cancer. However, the clinical roles and biological functions of lncRNA TUBA4B in epithelial ovarian cancer have yet to be fully clarified. The present study was conducted to explore the expression of lncRNA TUBA4B in human epithelial ovarian cancer tissues and potential roles of lncRNA TUBA4B in ovarian cancer cells. The matched epithelial ovarian cancer specimens and adjacent normal tissues were employed to detect the expression of lncRNA TUBA4B. The prognostic value of lncRNA TUBA4B for tumor progression and survival rate was investigated. The effects of lncRNA TUBA4B on ovarian cancer cell proliferation and migration were also explored. The expression of lncRNA TUBA4B was significantly decreased in epithelial ovarian cancer tissue specimens. The low lncRNA TUBA4B level was closely related with pathological grade, FIGO stage and lymph node metastases, and serum CA125 level. Enforced expression of lncRNA TUBA4B obviously reduced the proliferation of SKOV3 cells, and attenuated the activation of ERK and Akt signaling pathways. Our data demonstrate for the first time that lower lncRNA TUBA4B may be a novel independent prognostic biomarker for overall survival of epithelial ovarian cancer. Overexpression of lncRNA TUBA4B inhibits the proliferation of ovarian cancer cells. LncRNA TUBA4B may be an important target for therapeutic intervention in ovarian cancer.