GC-MS based metabolomics study of stems and roots of Ephedra sinica

Natural Sympathomimetic Drugs: From Pharmacology to Toxicology

Sympathomimetic agents are a group of chemical compounds that are able to activate the sympathetic nervous system either directly via adrenergic receptors or indirectly by increasing endogenous catecholamine levels or mimicking their intracellular signaling pathways. Compounds from this group, both used therapeutically or abused, comprise endogenous catecholamines (such as adrenaline and noradrenaline), synthetic amines (e.g., isoproterenol and dobutamine), trace amines (e.g., tyramine, tryptamine, histamine and octopamine), illicit drugs (e.g., ephedrine, cathinone, and cocaine), or even caffeine and synephrine. In addition to the effects triggered by stimulation of the sympathetic system, the discovery of trace amine associated receptors (TAARs) in humans brought new insights about their sympathomimetic pharmacology and toxicology. Although synthetic sympathomimetic agents are mostly seen as toxic, natural sympathomimetic agents are considered more complacently in the terms of safety in the vision of the lay public. Here, we aim to discuss the pharmacological and mainly toxicological aspects related to sympathomimetic natural agents, in particular of trace amines, compounds derived from plants like ephedra and khat, and finally cocaine. The main purpose of this review is to give a scientific and updated view of those agents and serve as a reminder on the safety issues of natural sympathomimetic agents most used in the community.

Comparison of Volatile Oils and Primary Metabolites of Raw and Honey-Processed Ephedrae Herba by GC-MS and Chemometrics

BACKGROUND

Ephedrae Herba (EH) is the terrestrial stem of Ephedra sinica Stapf, E. intermedia Schrenk et C. A. Mey., or E. equisetina Bge, which has been used as a diaphoretic, antiasthmatic, and diuretic. Honey-processed EH (HEH) is a widely used traditional Chinese medicine, and has a better effect of dispersing lung qi and relieving asthma and a lower effect of dispelling cold than raw EH (REH).

OBJECTIVE

To understand the differences of volatile oils and primary metabolites between REH and honey-processed HEH, and to provide a reference for elucidating the mechanism behind the effect of this processing.

METHODS

A system data acquisition and mining strategy was designed to investigate the differences of volatiles and primary metabolites between the REH and HEH, based on gas chromatography-mass spectrometry coupled with multivariate statistical analysis, including principal component analysis and orthogonal partial least squares discriminant analysis.

RESULTS

Overall, 15 volatile oils and 14 primary metabolites were shown to be potential characteristic markers differentiating REH and HEH.

CONCLUSION

The results may provide a scientific foundation for comprehensively revealing the honey-processing mechanism of EH.

HIGHLIGHT

Volatile oils and primary metabolites were used to distinguish REH and HEH and elucidate the processing mechanism of EH for the first time.

Antioxidant properties and qualitative analysis of phenolic constituents in Ephedra spp. by HPTLC together with injection port derivatization GC-MS

Ephedra herb extracts are being extensively investigated in terms of their antioxidative, antimicrobial and antiproliferative properties, with phenolic components being the general carriers of these bioactivities. Here we describe a comprehensive set of analytical methods employed to determine and characterize both the antioxidative activity and the qualitative profile of phenolic acids and flavonoids present in several Ephedra species of different geographical origin. Spectrophotometric methods were used to determine the total phenolic content, total flavonoid content and antioxidative activity. Multi-development HPTLC enabled chemical fingerprinting which can be used for species differentiation. Individual spots of the thin-layer chromatogram were subjected to GC-MS with injection port derivatization for identification, which was based on both the detected mass spectra and recorded retention indices. The results were compared and complemented with GC-MS using offline derivatization.

A review of the phytochemistry and pharmacological activities of Ephedra herb

Ephedra herb is a traditional Chinese medicine with a long history. Conventionally, it was used as a folk phytomedicine in many ancient medical books and traditional prescriptions. Up to date, a variety of specific ingredients have been found in Ephedra herb, mainly including alkaloids, flavonoids, tannins, polysaccharides, organic acids, volatile oils, and many other active compounds. These components from Ephedra herb account for its use as the accurate treatment of cold, cough, cardiovascular and immune system disease, cancer, microbial infection, and other diseases. Moreover, with the fast development of novel chemistry and medicine technology, new chemical constituents and pharmacological effects of Ephedra herb are increasingly identified, demonstrating their great potential for various diseases treatment. Therefore, further detailed understanding and investigation of this ancient herb will offer new opportunities to develop novel therapeutics. This study systematically reviews its progress of phytochemistry, traditional and modern pharmacology based on research data that have been reported, aiming at providing useful insight for commercial exploitation, further study and precision medication of Ephedra herb in future.

Effect of Chilled Ageing Conditioning at 4°C in Lamb Longissimus Dorsi Muscles on Water-Soluble Flavour Precursors as Revealed by a Metabolomic Approach

The objective of this study was to investigate, by a metabolomic approach, the effects of chilled ageing conditioning at 4°C in lamb longissimus dorsi (LD) muscles on water-soluble flavour precursors. The results showed that the content of nucleotide degradation products significantly increased (P<0.05) due to the adjusted biosynthesis of alkaloids derived from histidine and purine from day 0 to day 4. Additionally, the content of glycolytic compounds significantly increased (P<0.05) due to enhanced glycolysis, and the content of organic acid increased (P<0.05) because of the altered tricarboxylic acid cycle (TCA) from day 0 to day 4. In addition, the content of total free amino acids significantly increased (P<0.05), owing to the altered biosynthesis of amino acids from day 4 to day 8. These results are significant proof that there were quantitative changes observed in lamb flavour precursors during chilled ageing.

Preventive effect of Ephedra sinica extract on UVB-induced COX-2 and MMP-1 expression

Ultraviolet B (UVB)-induced cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-1 are representative markers for skin inflammation and photoaging, respectively. To evaluate compounds that may counteract the effects of UVB-induced skin damage, we developed an immortalized human keratinocyte (HaCaT) cell line with an MMP-1 reporter construct. Among the 30 botanical extracts screened, we selected Ephedra sinica extract (ESE) as a promising candidate and confirmed that ESE significantly suppresses UVB-induced COX-2 and MMP-1 expression in HaCaT cells. Treatment with ESE also potently suppressed UVB-induced ERK1/2 phosphorylation, as well as UVB-induced MEK1/2 and Raf phosphorylation in HaCaT cells. These findings suggest that our MMP-1 reporter system can be used to evaluate compounds with anti-inflammatory and anti-photoaging effects. We also report that ESE has potent suppressive effects against COX-2 and MMP-1 expression, which occurs via downregulation of Raf/MEK1/2/ERK1/2 phosphorylation.

The application of metabolomics for herbal medicine pharmacovigilance: a case study on ginseng

Herbal medicines are growing in popularity, use and commercial value; however, there remain problems with the quality and consequently safety of these products. Adulterated, contaminated and fraudulent products are often found on the market, a risk compounded by the fact that these products are available to consumers with little or no medical advice. Current regulations and quality control methods are lacking in their ability to combat these serious problems. Metabolomics is a biochemical profiling tool that may help address these issues if applied to quality control of both raw ingredients and final products. Using the example of the popular herbal medicine, ginseng, this essay offers an overview of the potential use of metabolomics for quality control in herbal medicines and also highlights where more research is needed.