Screening and evaluation of anti-SARS-CoV-2 components from Ephedra sinica by ACE2/CMC-HPLC-IT-TOF-MS approach.

Traditional Chinese medicines played an important role in the treatment of COVID-19 in 2020. Ephedra sinica, one of the major constituent herbs of multi-component herbal formula, has been widely used to treat COVID-19 in China. However, its active components are still unclear. The objectives of this study are to screen and evaluate active components from the traditional Chinese medicine Ephedra sinica for the treatment of COVID-19. In our study, we established an ACE2/CMC bioaffinity chromatography model, and then developed an ACE2/CMC-HPLC-IT-TOF-MS system for the active compounds screening and identification from Ephedra sinica extract. We performed molecular docking and surface plasmon resonance (SPR) assays to assess the binding characteristics (binding mode and KD value). We used CCK-8 staining to assess the toxicity of screened compounds, and also used SARS-CoV-2 pseudovirus to observe the viropexis effect of screened compounds in ACE2h cells. In this current work, one fraction was fished out, separated and identified as ephedrine (EP), pseudoephedrine (PEP), and methylephedrine (MEP). Binding assays showed that the three compounds could bind with ACE2 in a special way to some amino acid residues, similar to the way SARS-CoV-2 bound with ACE2. Additionally, the three compounds, especially EP, can inhibit the entrance of SARS-CoV-2 spike pseudovirus into ACE2h cells because they can reduce the entrance ratio of pseudovirus in the pseudovirus model. Overall, the ACE2/CMC-HPLC-IT-TOF-MS system was established and verified to be suitable for ACE2-targeted bioactive compound screening. EP, PEP, and MEP with ACE2-binding features were screened out from Ephedra sinica, and acted as blockers inhibiting SARS-CoV-2 spike pseudovirus entering ACE2h cells.

Validity of Selection Breeding for High Ephedrine-Alkaloid Content in E. sinica under Different Environments in Japan.

Dried terrestrial stems of Ephedra sinica are called 'Ephedra herb,' whose pharmacological effects are due mainly to two major ingredients, (-)-ephedrine and (+)-pseudoephedrine (total alkaloids which are defined in Japanese Pharmacopoeia (TA)). Ephedra herb is an important crude drug in Japan. However, E. sinica is widely distributed in arid areas of northeastern China and Mongolia. Recently, E. sinica has started to be cultivated in Japan. This study aimed to assess the validity of selection breeding on TA content of E. sinica in several locations in Japan. In this experiment, we grew approximately 350 seedlings and divided them randomly into seven groups. Nearly fifty plants were cultivated at each of seven locations. In Ibaraki, Yamanashi, and Shizuoka, average TA content of whole samples satisfied the criteria for Ephedra herb defined in Japanese Pharmacopoeia (7.0 mg/g of dry weight (DW)). Plants with high and intermediate TA content at four locations were selected and transplanted to Ibaraki. There were significant differences in TA content between selected plants with high and intermediate TA content before and after transplanting (p < 0.05). TA content of high-TA plants was significantly higher than that of control plants cultivated continuously at Ibaraki (p < 0.05). These results suggest that the selection on content of ephedrine alkaloids in E. sinica under various locations in Japan is valid, and high- TA E. sinica plants can be selected at various locations.

[The Adverse Effects of Ephedra Herb and the Safety of Ephedrine Alkaloids-free Ephedra Herb Extract (EFE)].

Ephedra Herb is defined in the 17th edition of the Japanese Pharmacopoeia (JP) as the terrestrial stem of Ephedra sinica Stapf., Ephedra intermedia Schrenk et C.A. Meyer, or Ephedra equisetina Bunge (Ephedraceae). The stems of Ephedra Herb contain greater than 0.7% ephedrine alkaloids (ephedrine and pseudoephedrine). Despite its high effectiveness, Ephedra Herb exert several adverse effects, including palpitation, excitation, insomnia, and dysuria. Both the primary and adverse effects of Ephedra Herb have been traditionally believed to be mediated by these ephedrine alkaloids. However, our study found that several pharmacological actions of Ephedra Herb were not associated with ephedrine alkaloids. We prepared an ephedrine alkaloid-free Ephedra Herb extract (EFE) by eliminating ephedrine alkaloids from Ephedra Herb extract (EHE) using ion-exchange column chromatography. EFE exerted analgesic, anti-influenza, and anticancer activities in the same manner as EHE. Moreover, EFE did not induce adverse effects due to ephedrine alkaloids, such as excitation, insomnia, and arrhythmias, and showed no toxicity. Furthermore, we evaluated the safety of EFE in healthy volunteers. The number of adverse event cases was higher in the EHE-treated group than in the EFE-treated group, although the difference was not significant. Our evidence suggested that EFE was safer than EHE.

Enantioseparation by Capillary Electrophoresis Using Cyclodextrins in an Amino Acid-Based Ionic Liquid Running Buffer.

For enantioseparations of chiral drugs in capillary electrophoresis, chiral ionic liquids (CIL) can be employed instead of traditional running buffer containing a chiral selector. CILs can be applied solely or in addition to the often used cyclodextrin derivatives. Here the separation of phenethylamines, especially of ephedrine, is described using tetrabutylammonium L-argininate (125 mM) in phosphate buffer (75 mM, pH 1.5) in addition to ß-cyclodextrin (30 mM). Using this dual-chiral running buffer system ephedrine, pseudoephedrine and methylephedrine, but not norephedrine, could be easily resolved.

Ephedrine-induced mitophagy via oxidative stress in human hepatic stellate cells.

The herb Ephedra sinica (also known as Chinese ephedra or Ma Huang), used in traditional Chinese medicine, contains alkaloids identical to ephedrine and pseudoephedrine as its principal active constituents. Recent studies have reported that ephedrine has various side effects in the cardiovascular and nervous systems. In addition, herbal Ephedra, a plant containing many pharmacologically active alkaloids, principally ephedrine, has been reported to cause acute hepatitis. Many studies reported clinical cases, however, the cellular mechanism of liver toxicity by ephedrine remains unknown. In this study, we investigated hepatotoxicity and key regulation of mitophagy in ephedrine-treated LX-2 cells. Ephedrine triggered mitochondrial oxidative stress and depolarization. Mitochondrial swelling and autolysosome were observed in ephedrine-treated cells. Ephedrine also inhibited mitochondrial biogenesis, and the mitochondrial copy number was decreased. Parkin siRNA recovered the ephedrine-induced mitochondrial damage. Excessive mitophagy lead to cell death through imbalance of autophagic flux. Moreover, antioxidants and reducing Parkin level could serve as therapeutic targets for ephedrine-induced hepatotoxicity.

Peptide Metal-Organic Frameworks for Enantioselective Separation of Chiral Drugs.

We report the use of a chiral Cu(II) 3D metal-organic framework (MOF) based on the tripeptide Gly-l-His-Gly (GHG) for the enantioselective separation of metamphetamine and ephedrine. Monte Carlo simulations suggest that chiral recognition is linked to preferential binding of one of the enantiomers as a result of either stronger or additional H-bonds with the framework that lead to energetically more stable diastereomeric adducts. Solid-phase extraction of a racemic mixture by using Cu(GHG) as the extractive phase permits isolating >50% of the (+)-ephedrine enantiomer as target compound in only 4 min. To our knowledge, this represents the first example of a MOF capable of separating chiral polar drugs.

The Pharmacological Actions of Ephedrine Alkaloids-free Ephreda Herb Extract and Preparation for Clinical Application.

Ephedra Herb is defined in the 17th edition of the Japanese Pharmacopoeia as the terrestrial stem of Ephedra sinica STAPF., Ephedra intermedia SCHRENK et C.A. MEYER, or Ephedra equisetina BUNGE (Ephedraceae) which contains more than 0.7% ephedrine alkaloids (ephedrine and pseudoephedrine). The primary effects and adverse effects of Ephedra Herb are traditionally believed to be mediated by ephedrine alkaloids. We recently reported that Ephedra Herb extract (EHE) exhibits antimetastatic and antitumor effects by suppressing the hepatocyte growth factor-c-Met signaling pathway through the inhibition of c-Met tyrosine kinase activity. We confirmed that the non-alkaloidal fraction of EHE had c-Met-inhibitory activity. Moreover, we discovered herbacetin glycosides in EHE and demonstrated that herbacetin, the aglycone of the glycosides, shows c-Met-inhibitory activity and analgesic action. These findings suggest that some pharmacological actions of EHE may be produced by its non-alkaloidal fraction, which does not cause the adverse effects of ephedrine alkaloids. Therefore, we prepared ephedrine alkaloids-free EHE (EFE) by removing ephedrine alkaloids from EHE using ion-exchange column chromatography. EFE had c-Met-inhibitory action, analgesic effects, and antiinfluenza activity similar to EHE but had no toxicity. Now, we are evaluating the safety of EFE in healthy volunteers and its efficacy in patients to obtain licensing approval for its therapeutic use in the future.

Carbon coated magnetic nanoparticles as a novel magnetic solid phase extraction adsorbent for simultaneous extraction of methamphetamine and ephedrine from urine samples.

This paper develops a highly selective, specific and efficient method for simultaneous determination of ephedrine and methamphetamine by a new carbon coated magnetic nanoparticles (C/MNPs) as a magnetic solid phase extraction (MSPE) adsorbent in biological urine medium. The characterization of synthesized magnetic nano adsorbent was completely carried out by various characterization techniques like Fourier transform infrared (FT-IR) spectroscopy, powder x-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). Nine important parameters influencing extraction efficiency including amount of adsorbent, amounts of sample volume, pH, type and amount of extraction organic solvent, time of extraction and desorption, agitation rate and ionic strength of extraction medium, were studied and optimized. Under optimized extraction conditions, a good linearity was observed in the concentration range of 100-2000ng/mL for ephedrine and 100-2500ng/mL for methamphetamine. Analysis of positive urine samples was carried out by proposed method with the recovery of 98.71 and 97.87% for ephedrine and methamphetamine, respectively. The results indicated that carbon coated magnetic nanoparticles could be applied in clinical and forensic laboratories for simultaneous determination of abused drugs in urine media.

Validated quantification method for five ephedrines in dietary supplements using LC-MS/MS: Application to 503 cases.

Ephedrines in dietary supplements can arise from herbs or illegal adulteration so a liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for separation and quantification of ephedrine, pseudoephedrine, norephedrine, norepseudoephedrine, and methyl-ephedrine, some of which are isomer pairs of pseudo-structures. This method includes liquid-liquid extraction of ephedrines from three typical dietary supplement matrices-solid, liquid, and oil-as well as liquid chromatographic separation. After liquid chromatographic separation, ephedrines are qualitatively and quantitatively analyzed using triple quadrupole mass spectrometry with positive electrospray ionization in multi-reaction monitoring (MRM) mode. Ephedrine recoveries in a solid matrix ranged from 53.3-91.5%, in a liquid matrix from 56.4-102.3%, and in an oil matrix from 51.7-01.2%. Linearity ranges were 10-1000ng/g in solid and oil matrix and 1-100ng/ml in liquid matrix. Accuracy was -11.5-16.3%. Intra-day and inter-day variation are less than 5.9% and 7.3%, respectively. Expanded uncertainty of quantification is less than 0.123ng/g in a solid matrix, less than 0.139ng/ml in a liquid matrix, and less than 0.158ng/g in an oil matrix. Data collected for more than 500 routine samples are presented and discussed.

Diazonium modification of porous graphitic carbon with catechol and amide groups for hydrophilic interaction and attenuated reversed phase liquid chromatography.

Porous graphitic carbon (PGC) is an increasingly popular and attractive phase for HPLC on account of its chemical and thermal stability, and its unique separation mechanism. However, native PGC is strongly hydrophobic and in some instances excessively retentive. As part of our effort to build a library of hydrophilic covalently modified PGC phases, we functionalized PGC with catechol and amide groups by means of aryl diazonium chemistry to produce two new phases. Successful grafting was confirmed by X-ray photoelectron spectroscopy (XPS). Under HILIC conditions, the Catechol-PGC showed up to 5-fold increased retention relative to unmodified PGC and selectivity that differed from four other HILIC phases. Under reversed phase conditions, the Amide-PGC reduced the retentivity of PGC by almost 90%. The chromatographic performance of Catechol-PGC and Amide-PGC is demonstrated by separations of nucleobases, nucleosides, phenols, alkaline pharmaceuticals, and performance enhancing stimulants. These compounds had retention factors (k) ranging from 0.5 to 13.

Capillary gas chromatography using a γ-cyclodextrin for enantiomeric separation of methylamphetamine, its precursors and chloro intermediates after optimization of the derivatization reaction.

The enantiomeric ratio of methylamphetamine (MAMP) is closely related to the optical activity of precursors and reagents used for the synthesis and this knowledge can provide useful information concerning the origins and synthetic methods used for illicit manufacture. The information can be utilized for regulation of the precursors and investigation of the manufacturing sources but this requires analytical procedures to determine purity of drug substances, impurity profiling and enantiomeric composition. In this study, a gas chromatography (GC) coupled with mass spectrometry (MS) method using a γ-cyclodextrin chiral stationary phase was developed and optimized for the simultaneous enantiomeric separations of MAMP and its common precursors, ephedrine, and pseudoephedrine, as well as its chlorointermediates formed during MAMP synthesis by the Emde method, after derivatization with trifluoroacetic anhydride. The optimization was performed using multivariate statistics (cluster analysis and principal components analysis) in order to select and compare optimal experimental conditions. Under the optimized experimental conditions, the calculated calibration curves showed good linearity range up to 0.1µg/mL for all tested analytes. The limits of detection were in the range of 0.002-0.008µg/mL and the coefficient of variability was between 1.0 and 3.9%. The method has the advantage of achieving excellent precision under repeatability and reproducibility conditions while detection by MS allows for the identity of analytes to be confirmed in a single analysis. The method was therefore applied satisfactory to MAMP analysis.

Comparative analysis of the main bioactive components of San-ao decoction and its series of formulations.

A high performance liquid chromatographic (HPLC) method with diode array detection (DAD) was established for simultaneous determination of seven main bioactive components in San-ao decoction and its series of formulae (San-ao decoction, Wu-ao decoction, Qi-ao decoction and Jia-wei San-ao decoction). Seven compounds were analyzed simultaneously with a XTerra C(18) column (4.6 mm × 250 mm, 5 µm) using a linear gradient elution of a mobile phase containing acetonitrile (A) and a buffer solution (0.02 mol/L potassium dihydrogen phosphate and adjusted to pH 3 using phosphoric acid) (B); the flow rate was 1.0 mL/min. The sample was detected with DAD at 210, 254 and 360 nm and the column was maintained at 30 °C. All the compounds showed good linearity (r2 > 0.9984) in the tested concentration range. The precisions were evaluated by intra-day and inter-day tests, and relative standard deviation (R.S.D.) values within the range of 0.83%–2.53% and 0.64%–2.77% were reported, respectively. The recoveries of the quantified compounds were observed to cover a range from 95.34% and 104.82% with R.S.D. values less than 2.72%. The validated method was successfully applied for the simultaneous determination of seven main bioactive components including ephedrine (1), amygdalin (2), liquiritin (3), benzoic acid (4), isoliquiritin (5), formononetin (6) and glycyrrhizic acid (7) in San-ao decoction and its series of formulae. The results also showed a wide variation in the content of the identified active compounds in these samples, which could also be helpful to illustrate the drug interactions after some herbs combined in different formulations.

Amino acid bound surfactants: a new synthetic family of polymeric monoliths opening up possibilities for chiral separations in capillary electrochromatography.

By combining a novel chiral amino-acid surfactant containing an acryloyl amide tail, a carbamate linker, and a leucine headgroup of different chain lengths with a conventional cross-linker and a polymerization technique, a new "one-pot" synthesis for the generation of amino-acid based polymeric monolith is realized. The method promises to open up the discovery of an amino-acid based polymeric monolith for chiral separations in capillary electrochromatography (CEC). The possibility of enhanced chemoselectivity for simultaneous separation of ephedrine and pseudoephedrine containing multiple chiral centers and the potential use of this amino-acid surfactant bound column for CEC and CEC coupled to mass spectrometric detection are demonstrated.

Simultaneous identification of the enantiomers and diastereomers of N,O-di-trifluoroacetylated ephedrine and norephedrine in blood plasma using chiral capillary gas chromatography-mass spectrometry with selected ion monitoring.

A method for identifying the enantiomers of N,O-di-trifluoroacetylated ephedrine (EP) and norephedrine (NE) and the enantiomers of pseudoephedrine (PEP) and pseudonorephedrine (PNE) in plasma was developed using chiral capillary gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM). N,O-Di-trifluoroacethyl (TFA) derivatization was accomplished in a dried hydrochloride extract of plasma (minimum quantity of 0.2 mL). An SIM GC-MS method with a ß-cyclodextrin chiral capillary column allowed the successful and simultaneous detection of each TFA-derivatized stereoisomer of EP, NE, PEP, PNE, and an internal standard (IS; S-(+)-ethylamphetamine). Each TFA-drivatized stereoisomer was identified using four mass fragment ions (m/z 140, 154, 168, and 230). The TFA-derivatized stereoisomers of EP, NE, PEP, PNE, and IS were separated completely and were detected with sufficient sensitivity. The assay allowed the stereoisomers to be determined in a linear range of 12.5-1250 ng/mL for the EP stereoisomers and a linear range of 5-1250 ng/mL for the PEP, NE, and PNE stereoisomers. The detection limits were 7.5 ng/mL for the EP stereoisomers and 2.5 ng/mL for the PEP, NE, and PNE stereoisomers. The intra- and interday precisions were less than 5.9% and 8.2%, respectively. This chiral capillary SIM GC-MS method was sufficiently effective in the analysis of plasma from users of over-the-counter cold medicines and was also fully applicable to the plasma analysis of guinea pigs following their treatment with racemic EP.

Monolithic molecular imprinted polymer fiber for recognition and solid phase microextraction of ephedrine and pseudoephedrine in biological samples prior to capillary electrophoresis analysis.

A novel capillary electrophoresis (CE) method coupled with monolithic molecular imprinted polymer (MIP) fiber based solid phase microextraction (SPME) was developed for selective and sensitive determination of ephedrine (E) and pseudoephedrine (PE). With in situ polymerization in a silica capillary mold and E as template, the MIP fibers could be produced in batch reproducibly and each fiber was available for 50 extraction cycles without significant decrease in extraction ability. Using the MIP fiber under optimized extraction conditions, CE detection limits of E and PE were greatly lowered from 0.20 to 0.00096 µg/mL and 0.12 to 0.0011 µg/mL, respectively. Analysis of urine and serum samples by the MIP-SPME-CE method was also performed, with results indicating that E and PE could be selectively extracted. The recoveries and relative standard deviations (RSDs) for sample analysis were found in the range of 91-104% and 3.8-9.1%, respectively.

Comparison of conventional hollow fiber based liquid phase microextraction and electromembrane extraction efficiencies for the extraction of ephedrine from biological fluids.

In the present study, hollow fiber liquid phase microextraction (HF-LPME) based on pH gradient and electromembrane extraction (EME) coupled with high-performance liquid chromatography (HPLC) was compared for the extraction of ephedrine from biological samples. The influences of fundamental parameters affecting the extraction efficiency of ephedrine were studied and optimized for both methods. Under the optimized conditions, preconcentration factors of 120 and 35 for urine and 51 and 8 for human plasma were obtained using EME and HF-LPME, respectively. The calibration curves showed good linearity for urine and plasma samples by both methods with the coefficient of estimations higher than 0.98. The limits of detection were obtained 5 and 10 ng mL(-1) using EME and 60 and 200 ng mL(-1) by HF-LPME for urine and plasma samples respectively. The relative standard deviations of the analysis were found in the range of 5.2-8.6% (n=3). The results showed that in comparison with HF-LPME based on pH gradient, EME is a much more effective transport process, providing high extraction efficiencies in very short time.

Separation of enantiomers of ephedrine by capillary electrophoresis using cyclodextrins as chiral selectors: comparative CE, NMR and high resolution MS studies.

The enantiomer migration order (EMO) of ephedrine was investigated in the presence of various CDs in CE. The molecular mechanisms of chiral recognition were followed for the ephedrine complexes with native α- and ß-CD and heptakis(2,3-di-O-acetyl-6-O-sulfo)-ß-CD (HDAS-ß-CD) by CE, NMR spectroscopy and high-resolution MS. Minor structural differences were observed between the complexes of ephedrine with α- and ß-CD although the migration order of enantiomers was opposite when these two CDs were applied as chiral selectors in CE. The EMO was also opposite between ß-CD and HDAS-ß-CD. Significant structural differences were observed between ephedrine complexes with the native CDs and HDAS-ß-CD. The latter CD was advantageous as chiral CE selector not only due to its opposite electrophoretic mobility compared with that of the cationic chiral analyte, but also primarily due to its enhanced chiral recognition ability towards the enantiomers of ephedrine.

The history of Ephedra (ma-huang).

Ephedra is a Chinese shrub which has been used in China for medicinal purposes for several thousand years. The pure alkaloid ephedrine was first isolated and characterised by Nagai in 1885. It was then forgotten until it was rediscovered by Chen and Schmidt in the early 1920s. Its actions on the adrenoceptors could be classified into separate alpha and beta effects--a defining moment in the history of autonomic pharmacology. Ephedrine became a highly popular and effective treatment for asthma, particularly because, unlike adrenaline (until then the standard therapy), it can be given by mouth. Ephedrine as a treatment for asthma reached its zenith in the late 1950s, since when there has been a gradual and inevitable decline in its therapeutic use. From mainstream medicine, ephedrine moved into the twilight zone of street drugs and nutritional supplements. Ephedra and ephedrine products are now banned in many countries, as they are a major source for the production of the addictive compound methamphetamine (crystal meth).