Effect of in vitro gastrointestinal digestion on phenolic compounds and antioxidant properties of soluble and insoluble dietary fibers derived from hulless barley.

In this study, the bioaccessibility and antioxidant activity of phenolic compounds in insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) derived from hulless barley were evaluated by an in vitro gastrointestinal (GI) digestion model. The total phenolic and flavonoid contents, as well as antioxidant activity of phenolic compounds in IDF and SDF following GI digestion were studied. The results obtained showed an increase in total phenolic and flavonoid contents, as well antioxidant activity compared with undigested extracts. Moreover, the bioaccessibility indexes of phenolic compounds in IDF and SDF were 490.90 ± 3.10% and 1608.79 ± 40.63% respectively, after GI digestion. Similarly, the bioaccessibility indexes of flavonoids in IDF and SDF were 179.20 ± 15.16% and 814.36 ± 26.31%, respectively. Based on our findings, individual phenolic compounds show different stability in the digestion process. The content of ferulic acid has different trends in IDF and SDF during GI digestion. This study could provide a scientific basis for hulless barley DF as valuable food additives. PRACTICAL APPLICATION: Hulless barley is a unique cereal with potential health benefits due to high dietary fiber (DF) content and phenolic compounds. Phenolic compounds could be linked to DF through chemical bonds. Phenolic compounds in DF can be slowly and continuously released under acidic, alkaline, and enzymatic conditions by in vitro gastrointestinal digestion, which could maintain a higher phenolic concentration in the bloodstream and be beneficial for human health. This study could provide a scientific basis for hulless barley DF as valuable food additives.

Troxerutin and Cerebroprotein Hydrolysate Injection Protects Neurovascular Units from Oxygen-Glucose Deprivation and Reoxygenation-Induced Injury In Vitro.

Cerebral ischemia/reperfusion (I/R) injury involves complex events of cellular and molecular processes. Previous studies suggest that a neurovascular unit (NVU) acts as an intricate network to maintain the neuronal homeostatic microenvironment. The present study established an NVU model for oxygen-glucose deprivation and reoxygenation (OGD/R) damage, trying to target the major components of the NVU using a coculture of rat neurons, astrocytes, and rat brain microvascular endothelial cells (rBMECs) to investigate the therapeutic effects of troxerutin and cerebroprotein hydrolysate injections (TCHis). The study observed that OGD/R downregulated the expressions of GAP-43, Claudin-5, and AQP-4 obviously detected by Western blotting and immunocytochemical analysis, respectively, while TCHi ameliorated the effect of OGD/R significantly. Meanwhile, TCHi alleviated the abnormalities of ultrastructure of neurons and rBMECs induced by OGD/R. Furthermore, both levels of inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and cell adhesion molecules (VCAM-1 and ICAM-1) detected by ELISA in NVU supernatant were found elevated significantly through OGD/R, but TCHi ameliorated the trend. In addition, TCHi also mitigated the increase of proapoptotic factors (Bax, p53, and caspase-3) induced by OGD/R in NVU model statistically. All these findings demonstrated that TCHis played a protective role, which was reflected in anti-inflammation, antiapoptosis, and blood-brain barrier maintenance. The results of the study concluded that the NVU is an ideal target and TCHi acts as a neuroprotective agent against cerebral I/R injuries.

Comparative Evaluation of Soluble and Insoluble-Bound Phenolics and Antioxidant Activity of Two Chinese Mistletoes.

Mistletoes are used medicinally in order to treat various human illnesses. Few studies have reported on the phenolic content and antioxidant properties of Chinese mistletoes (CMs). In this work, the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities of soluble and insoluble-bound phenolic extracts from CMs hosted by Camellia assamica (Mast.) Chang (CMC) and Pyrus, i, f. (CMP) were compared. Phenolic compounds in CMC and CMP were identified and quantified using high-performance liquid chromatography (HPLC). The results indicated that the TPC of soluble phenolic extracts was higher than insoluble-bound phenolic counterparts in both CMC and CMP. In addition, the TPC of soluble, insoluble-bound and total phenolic fractions (9.91 ± 0.23, 4.59 ± 0.27 and 14.50 ± 0.35 µmol ferulic acid equivalents per gram (FAE/g) dry sample) extracted from CMP were higher than those extracted from CMC. The soluble phenolic extracts in CMP showed higher antioxidant activities than those in CMC. Eighteen phenolic compounds from soluble and insoluble-bound phenolic extracts from the CMs were identified and quantified by HPLC. This study indicates that CMC and CMP, especially the latter, could be sources of antioxidants in human health care.

Panax notoginseng Saponins Attenuate Phenotype Switching of Vascular Smooth Muscle Cells Induced by Notch3 Silencing.

Panax notoginseng saponins (PNS) could maintain vascular smooth muscle cells (VSMCs) in stable phenotypes so as to keep blood vessel elasticity as well as prevent failing in endovascular treatment with stent. Downregulation of Notch3 expression in VSMCs could influence the phenotype of VSMCs under pathologic status. However, whether PNS is able to attenuate the Notch3 silencing induced phenotype switching of VSMCs remains poorly understood. Primary human VSMCs were transfected with a plasmid containing a small interfering RNA (siRNA) against Notch3 and then exposed to different doses of PNS. The control groups included cells not receiving any treatment and cells transfected with a control siRNA. Phenotypic switching was evaluated by observing cell morphology with confocal microscopy, as well as examining α-SM-actin, SM22α, and OPN using Western blot. Downregulated Notch3 with a siRNA induced apparent phenotype switching, as reflected by morphologic changes, decreased expression of α-SM-actin and SM22α and increased expression of OPN. These changes were inhibited by PNS in a dose-dependent manner. The phenotype switching of VSMCs induced by Notch3 knockdown could be inhibited by PNS in a dose-dependent manner. Our study provided new evidence for searching effective drug for amending stability of atherosclerotic disease.