Efficacy of aqueous extract of Hippophae rhamnoides and its bio-active flavonoids against hypoxia-induced cell death

A Comprehensive Review on Extraction, Structure, Detection, Bioactivity, and Metabolism of Flavonoids from Sea Buckthorn (Hippophae rhamnoides L.)

Sea buckthorn (Hippophae rhamnoides L.) is an important plant with homology of medicine and food. It has rich nutritional and medicinal properties. It is used as a traditional Chinese medicine with therapeutic functions of invigorating spleen, relieving cough, eliminating food, eliminating phlegm, dispersing blood stasis, and promoting blood circulation. This review comprehensively summarized flavonoids from sea buckthorn (Hippophae rhamnoides L.), including extraction methods (solvent extraction, ultrasound-assisted extraction, microwave-assisted extraction, enzyme-assisted extraction, and collaborative extraction), two structure types (18 flavone aglycones and 81 flavone glycosides), detection methods (UV, HPLC, and NMR), bioactivities (antiviral, anti-inflammatory, hepatoprotective, weight-reducing, and hypoglycemic activities), and physiological metabolisms (most of flavonoids are converted into small molecule monophenolic acids through intestinal microbial catabolism). It will supply an important theoretical basis and valuable reference for researching and exploiting sea buckthorn (Hippophae rhamnoides L.) in the future. Practical Applications. Sea buckthorn (Hippophae rhamnoides L.) is an edible and medical plant with many functional properties. A comprehensive review on extraction, structure, detection, bioactivity, and metabolism of flavonoids from sea buckthorn (Hippophae rhamnoides L.) was made in this paper. This review will provide an important foundation for further studies of sea buckthorn (Hippophae rhamnoides L.) focusing on its development and utilization.

Expression Profiles of Long Noncoding RNAs in Mice with High-Altitude Hypoxia-Induced Brain Injury Treated with Gymnadenia conopsea (L.) R. Br

BACKGROUND

The unique geographical environment at high altitudes may cause a series of diseases, such as acute altitude reaction, cerebral edema, and pulmonary edema. Gymnadenia conopsea (L.) R. Br. has been reported to have an effect on high-altitude hypoxia. However, the molecular mechanism, especially the expression of long noncoding RNAs (lncRNAs), is not yet clear.

METHODS

The expression profiles of lncRNAs in high-altitude hypoxia-induced brain injury mice treated with Gymnadenia conopsea (L.) R. Br. by using a microarray method.

RESULTS

A total of 226 differentially expressed lncRNAs, 126 significantly dysregulated mRNAs and 23 differentially expressed circRNAs were detected (>2.0-fold, p<0.05). The expression of selected lncRNAs, mRNAs and circRNAs was validated by qRT-PCR. KEGG analysis showed that the mRNAs coexpressed with lncRNAs were involved in inflammation and hypoxia pathways, including the HIF-1, PI3K-Akt, and NF-kappa B signaling pathways. The lncRNA-TF network analysis results indicated that the lncRNAs were regulated mostly by HMGA2, SRY, GATA4, SOX5, and ZBTB16.

CONCLUSION

This study is the first to report the expression profiles of lncRNAs, mRNAs and circRNAs in mice with high-altitude hypoxia-induced brain injury treated with Gymnadenia conopsea (L.) R. Br. and may improve the understanding of the molecular mechanism of Gymnadenia conopsea (L.) R. Br. in treating high altitude hypoxia-induced brain injury.

Rapid and selective mobilization of specific stem cell types after consumption of a polyphenol-rich extract from sea buckthorn berries (Hippophae) in healthy human subjects

Purpose

The aim of this study was to evaluate the effects of a proanthocyanidin-rich extract of sea buckthorn berry (SBB-PE) on the numbers of various types of adult stem cells in the blood circulation of healthy human subjects.

Study design and methods

A randomized, double-blind, placebo-controlled, cross-over trial was conducted in 12 healthy subjects. Blood samples were taken immediately before and at 1 and 2 hours after consuming either placebo or 500 mg SBB-PE. Whole blood was used for immunophenotyping and flow cytometry to quantify the numbers of CD45dim CD34+ CD309+ and CD45dim CD34+ CD309− stem cells, CD45− CD31+ CD309+ endothelial stem cells, and CD45− CD90+ mesenchymal stem cells.

Results

Consumption of SBB-PE was associated with a rapid and highly selective mobilization of CD45dim CD34+ CD309− progenitor stem cells, CD45− CD31+ CD309+ endothelial stem cells, and CD45− CD90+ lymphocytoid mesenchymal stem cells. In contrast, only minor effects were seen for CD45dim CD34+ CD309+ pluripotential stem cells.

Conclusion

Consumption of SBB-PE resulted in selective mobilization of stem cell types involved in regenerative and reparative functions. These data may contribute to the understanding of the traditional uses of SBB for preventive health, regenerative health, and postponing the aging process.

UPLC-ESI-MS/MS and HPTLC Method for Quantitative Estimation of Cytotoxic Glycosides and Aglycone in Bioactivity Guided Fractions of Solanum nigrum L

Solanum nigrum L., is traditionally used for the management of the various liver disorders. Investigating the effect of polarity based fractionation of S. nigrum for its hepatoprotective effect on Hep G2 cells in vitro to provide base of its activity by quantifying in steroidal glycosides responsible for hepatoprotective potential. A new UPLC-ESI-MS/MS method following a high performance thin layer chromatography (HPTLC) has been developed and validated for quantification of steroidal glycosides and aglycone (solasonine, solamargine, and solasodine, respectively). The in vitro antioxidant potential, total phenolics, and flavonoid content were also determined in different fractions. The newly developed UPLC-ESI-MS/MS and HPTLC methods were linear (r² ≥ 0.99), precise, accurate, and showing recovery more than 97%. The n-butanol enriched fraction of S. nigrum berries was found to be the most potent hepatoprotective fraction against all other fractions as it showed significantly (p < 0.01) better in vitro anti-oxidant potential than other fractions. Quantification by both methods revealed that, content of steroidal glycosides and aglycones are more than 20% in n-butanol fraction as compared to other fractions. The screened steroidal glycoside n-butanol enriched fraction underwent bioefficacy studies against D-galactosamine and H₂O₂ induced toxicity in HepG2 cell line showing significant (p < 0.05) liver protection. However, developed method can be used for the quality control analysis with respect to targeted metabolites and it can be explored for the pharmacokinetic and pharmacodynamic analysis in future.

The role of miR-34a in the hepatoprotective effect of hydrogen sulfide on ischemia/reperfusion injury in young and old rats

Hydrogen sulfide (H2S) can protect the liver against ischemia-reperfusion (I/R) injury. However, it is unknown whether H2S plays a role in the protection of hepatic I/R injury in both young and old patients. This study compared the protective effects of H2S in a rat model (young and old animals) of I/R injury and the mechanism underlying its effects. Young and old rats were assessed following an injection of NaHS. NaHS alone reduced hepatic I/R injury in the young rats by activating the nuclear erythroid-related factor 2 (Nrf2) signaling pathway, but it had little effect on the old rats. NaHS pretreatment decreased miR-34a expression in the hepatocytes of the young rats with hepatic I/R. Overexpression of miR-34a decreased Nrf-2 and its downstream target expression, impairing the hepatoprotective effect of H2S on the young rats. More importantly, downregulation of miR-34a expression increased Nrf-2 and the expression of its downstream targets, enhancing the effect of H2S on hepatic I/R injury in the old rats. This study reveals the different effects of H2S on hepatic I/R injury in young and old rats and sheds light on the involvement of H2S in miR-34a modulation of the Nrf-2 pathway.