Determination of ephedra alkaloid and caffeine concentrations in dietary supplements and biological fluids

A Pharmacokinetic Study of Ephedrine and Pseudoephedrine after Oral Administration of Ojeok-San by Validated LC-MS/MS Method in Human Plasma

A sensitive and reproducible liquid chromatography-tandem mass spectrometry (LC-MS/MS) system was developed and fully validated for the simultaneous determination of ephedrine and pseudoephedrine in human plasma after oral administration of the herbal prescription Ojeok-san (OJS); 2-phenylethylamine was used as the internal standard (IS). Both compounds presented a linear calibration curve (r² ≥ 0.99) over a concentration range of 0.2–50 ng/mL. The developed method was fully validated in terms of selectivity, lower limit of quantitation, precision, accuracy, recovery, matrix effect, and stability, according to the regulatory guidelines from the U.S. Food and Drug Administration and the Korea Ministry of Food and Drug Safety. This validated method was successfully applied for the pharmacokinetic assessment of ephedrine and pseudoephedrine in 20 healthy Korean volunteers administered OJS.

Detection of the chiral drug Ephedrine by resonance Rayleigh scattering based on Ce3+ functionalized gold nanoparticles

Two chiral drugs, ephedrine (EH) and pseudoephedrine (PEH), were commonly used in clinical treatment. Ephedrine (EH) and pseudoephedrine (PEH) could make different changes in resonance Rayleigh scattering spectrum of the detection system which use Ce³⁺ functionalized gold nanoparticles as probe. Therefore, a new method of detecting EH and PEH separately was developed. The RRS spectrum and UV-Vis absorption spectrum of AuNPs-Ce³⁺ detection system was analyzed in order to discuss the mechanism. Under optimal experimental conditions, the linear range of EH and PEH were 20-920 ng/mL and 40-520 ng/mL, respectively. The detection limit were 1.9 ng/mL and 3.8 ng/mL, respectively. Last used for actual testing, this method had obtained good results.

Screening of Weight-Loss Herbal Products for Synthetic Anti-Obesity Adulterants: A Target-Oriented Analysis by Liquid Chromatography-Tandem Mass Spectrometry

BACKGROUND

The medical and social impact of being overweight, as well as the difficulty in making long-term changes in diet, physical activity, and pitfalls associated with allopathic management, lure obese individuals to over-the-counter weight-loss herbal products (WHPs). However, the safety of herbals is questionable, as reports from all over the world suggest adulteration with synthetic weight loss agents. Objective: The present study was carried out to develop a rapid and sensitive method to screen potential weight loss adulterants in WHPs. Methodology: We procured 33 licensed brands of WHPs that are available in Puducherry (India) and through web stores. Drug-free spiked herbal matrices were used for internal proficiency testing. Spiked herbal matrices and samples were extracted and centrifuged. The supernatant was collected and subjected to liquid chromatography-tandem mass spectrometry analyses. Isocratic elution was carried out by the mobile phase of methanol: 0.1% v/v formic acid (70%:30% v/v) through a C₁₈ column. Analytes were monitored in electrospray ionization positive and negative modes, and an multiple reaction monitoring (MRM) scan was used. Results: Run time was 12 min. Intra- and inter-day precision was < 15% and recoveries were in the range of 99% to 115%. Limit of quantification (LOQ) of the analytes were in the range of 0.1 to 0.3 ng/ml. Conclusion: We developed a sensitive and rapid validated method for the detection of potential adulterants in WHPs. None of the WHPs analyzed were found to contain adulterants. The proposed method will be useful for routine monitoring. WHPs analyzed in this study were not adulterated indicating that WHPs from licensed sources are reliable.

Preventive Effect of Raw Liubao Tea Polyphenols on Mouse Gastric Injuries Induced by HCl/Ethanol via Anti-Oxidative Stress

Liubao tea is a type of traditional Chinese tea, belonging to the dark teas. This study is a basic research of the contained polyphenols (active substances) and detected preventive effects of polyphenols of raw Liubao tea (PRLT) on mouse gastric injuries induced by HCl/ethanol. High-pressure liquid chromatography was used to analyze the components of PRLT. Furthermore, a mouse gastric injury model was established to observe the preventive effects. PRLT was shown to contain gallic acid, EGC (epigallocatechin), catechin, caffeine, EC (epicatechin), EGCG (epigallocatechin gallate), GCG (gallocatechin gallate), and ECG (epicatechin gallate). The results of the in vivo study indicate that PRLT can inhibit the observed increase of gastric juice volume and decrease of gastric juice pH caused by gastric injury. PRLT can decrease the serum levels of IL-6 (interleukin-6), IL-12 (interleukin-12), TNF-α (tumor necrosis factor-α), and IFN-γ (interferon-γ) in mice with gastric injuries. Moreover, it can also increase the serum levels of SS (somatostatin) and VIP (vasoactive intestinal peptide) and reduce the serum levels of both SP (substance P) and ET-1 (endothelin-1). PRLT was also shown to increase SOD (superoxide dismutase) and GSH (glutathione) levels and decrease MDA (malondialdehyde) level. The detection of mRNA and protein in gastric tissues indicates that PRLT could also up-regulate the expression of Cu/Zn-SOD (copper/zinc superoxide dismutase), Mn-SOD (manganese superoxide dismutase), CAT (catalase), nNOS (neuronal nitric oxide synthase), and eNOS (endothelial nitric oxide synthase) and down-regulate the expression of both iNOS (inducible nitric oxide synthase) and COX-2 (cyclooxygenase-2). Thus, PRLT possess a good preventive effect on gastric injury, which is directly related to the contained active substance. PRLT show good anti-oxidative and preventive effect in gastric injury and offer promising application value.

Identification of Isomeric Ephedrines by Cold Ion UV Spectroscopy: Toward Practical Implementation

Ephedrine and pseudoephedrine are stimulant drugs whose use is prohibited in athletic competition by the World Anti-Doping Agency (WADA) at very different threshold doping violation concentrations. We use a recently developed universal approach that integrates UV photofragmentation spectroscopy of cold ions with Orbitrap mass spectrometry (MS) for highly selective and highly sensitive identification of these diastereomers. Both species can be selectively detected at a solution concentration of a few tens of ng/mL, which is almost 3 orders of magnitude lower than the threshold concentration required by WADA. Relative concentrations of the isomers in solutions have been determined with the standard deviation of 3.1%, when the ions were cooled in an ion trap maintained at T = 6 K. Considering practical implementation of the method, we evaluated its performance for a simplified instrumentation. At an affordable elevated temperature of ∼70 K and with a low-maintenance midbandwidth optical parametric oscillator, a few second measurement should yield nearly the same selectivity and only ten times lower sensitivity than with the current research grade instrument.

Ephedra increases VO2, impairs thermoregulation and cardiovascular function, but does not enhance exercise performance

The dietary supplement ephedra is a potent sympathomimetic that was banned by the US Food and Drug Administration in 2003 because of its deleterious effects on cardiovascular function and thermoregulation during exercise. Unfortunately, extracts of ephedra can still be obtained via the internet and are in use worldwide. The horse is the only athletic species other than humans that sweats to thermoregulate and it controls cardiovascular function in a similar fashion. The purpose of this study was to use the horse to examine the acute effects of ephedra (Ma Huang) to investigate on markers of performance as well as effects on cardiovascular function and thermoregulation during acute exercise. Six Standardbred mares (~450 kg; 6-12 years of age) were used in a crossover design consisting of a ephedra (Ma Huang containing 8% ephedra alkaloid) and control (applesauce) group. All horses performed an incremental graded exercise test (GXT) at a 6% fixed grade to measure oxygen uptake (VO2), run time, velocity at VO2max, maximal velocity, recovery time, haematocrit, total plasma protein concentration, heart rate, right ventricular pressure (RVP), pulmonary arterial pressure (PAP), rectal temperature and recovery. Measurements were recorded at rest, during exercise and post 2 and 5 min recovery. There was a difference (P<0.05) in pre-exercise haematocrit but not in any other haematocrit or plasma protein sampling intervals. VO2 was greater (P<0.05) for the ephedra group before exercise, at each step of the GXT, at VO2max, and during recovery compared to the control group. Recovery time was significantly different, but run time was not (P≯0.05). Heart rate was elevated (P<0.05) at 2 and 5 min recovery in horses administered ephedra. Significant differences were observed for RVP and PAP and rectal temperature during recovery. Recovery score (sweating response, respiration rate, behaviour) was altered (P<0.05) by ephedra administration. These data suggests an increase in energy expenditure and thermogenesis when horses consume ephedra. However, markers of performance (run time, velocity at VO2max, and maximal velocity completed) were not altered by ephedra administration.

New potentiometric sensors based on selective recognition sites for determination of ephedrine in some pharmaceuticals and biological fluids

New cost-effective potentiometric membrane sensors with cylindrical configuration responsive to ephedrine are described. The sensors setup is, based on the use of triacetyl-β-cyclodextrin [(triacetyl-β-CD)] as a neutral ionophore embedded in a plasticized poly (vinyl chloride) (PVC) matrix (sensor I) and carboxylated poly(vinyl chloride) [(PVC-COOH)] as a simultaneous plastic matrix and ion exchanger (sensor II). Both sensors showed significant enhancement of response towards ephedrinium cation (EPD(+)) over a concentration range of 3.0 × 10(-5)-8.0 × 10(-3) mol L(-1) at pH 4-9 and 3-8 with low detection limits of 5.7 × 10(-6) and 6.2 × 10(-6) mol L(-1) for sensors (I) and (II), respectively. The sensors displayed near-Nernstian cationic slope of 57.0 and 55.6 mV decade(-1) for EPD(+) and the effects of lipophilic salts and various foreign common ions were examined. The sensors were also satisfactorily used as tubular detectors in a double channel flow injection system. The intrinsic characteristics of the detectors in a low dispersion manifold under hydrodynamic mode of operation were determined and compared with data obtained under batch mode of operation. Validation of the method revealed good performance characteristics including long life span, good selectivity for EPD(+) over a wide variety of other organic compounds, long term stability, high reproducibility, fast response, low detection limit, wide measurement range, acceptable accuracy and precision. Applications of the sensors to the determination of EPD(+) in pharmaceutical formulations and spiked biological fluid samples were carried out and compared with standard techniques. Notably, the sensors introduced offer several advantages over many of those previously described that are amenable to quality control/quality assurance assessment of the homogeneity, stability and purity of ephedrine drug tablets.

Nutritional supplements: prevalence of use and contamination with doping agents

Based upon recent sales numbers, nutritional supplements play a key role in the lifestyle of a substantial proportion of the population. As well as products such as vitamins or minerals, several precursors of anabolic steroids are marketed as nutritional supplements. Another group of commercially available supplements are products for weight loss based upon herbal formulations originating from Ephedra species. Apart from supplements indicating the presence of these active compounds, numerous non-hormonal nutritional supplements were found that were contaminated with non-labelled anabolic steroids. Stimulating agents other than naturally occurring analogues of ephedrine were detected. A major group using dietary supplements are sportsmen, ranging from amateur level to elite athletes. Besides the possible health risks associated with the use of dietary supplements, athletes should take care not to violate the rules of the World Anti-Doping Agency because athletes remain responsible for substances detected in their biofluids, irrespective of their origin. Several analytical methods have been developed to determine the presence of doping agents as contaminants. The present review attempts to address the issues concerning the use of nutritional supplements and the detection of doping agents as contaminants in dietary supplements.

Cardiotoxicity of Ma Huang/caffeine or ephedrine/caffeine in a rodent model system

Ma Huang (equivalent to 0, 12.5, 25, or 50 mg/kg ephedrine) or ephedrine (0, 6.25, 12.5, 25 mg/kg) were administered as one bolus oral dose to male F344 rats with and without caffeine. The herbal medicine Ma Huang (ephedra) in combination with caffeine caused rapid clinical signs of toxicity including salivation, hyperactivity, ataxia, and eventually lethargy, and failure to respond to stimuli. When this syndrome of clinical signs emerged, animals were moribund sacrificed, and a histological analysis for heart lesions performed. Cardiotoxicity included hemorrhage, necrosis, and degeneration in the ventricles or interventricular septum within 2-4 hours after treatment with Ma Huang (ephedra)/caffeine or ephedrine (the principal active component in Ma Huang)/caffeine. There was a steep dose response curve for cardiotoxicity with minimal toxicity seen at levels of Ma Huang (equivalent to 12.5 mg/kg ephedrine) with caffeine. However, cardiotoxic lesions occurred in 28% of animals with Ma Huang dosages equivalent to 25 mg/kg ephedrine with 15 or 30 mg/kg caffeine, and in 90% of animals at Ma Huang exposures equivalent to 50 mg/kg ephedrine with 15 or 30 mg/kg caffeine. Cardiotoxic lesions occurred in 47% of animals in the 25 mg/kg ephedrine groups with caffeine at 7.25, 15, or 30 mg/kg. There was no statistical difference in the occurrence of cardiotoxic lesions when 15 or 30 mg/kg caffeine was combined with Ma Huang equivalent to 25 or 50 mg/kg ephedrine; likewise there was no statistical difference in the occurrence of cardiotoxic lesions when 7.25, 15, or 30 mg/kg caffeine was combined with 25 mg/kg ephedrine. These results show that the cardiotoxic effects of the herbal medicine, Ma Huang, are similar to that of ephedrine, the principal active ingredient in the herbal medicine. The combination of Ma Huang or ephedrine with caffeine enhanced the cardiotoxicity over that with the herbal medicine or the active ingredient alone.

A rapid and simple procedure for the determination of ephedrine alkaloids in dietary supplements by gas chromatography–mass spectrometry

A simple method for the determination of ephedrine alkaloids: ephedrine (EF), pseudoephedrine (PE), norpseudoephedrine (NPE), norephedrine (NE) and methylpseudoephedrine (MPE) in dietary supplements by gas chromatography-mass spectrometry is described. After the addition of 3,4-methylenedioxypropylamphetamine as internal standard, a liquid-liquid extraction procedure in alkaline conditions with chloroform/isopropanol (9:1, v/v) was applied to the samples prior to analysis. Chromatography was performed on a fused capillary column and analytes, derivatized with pentafluoropropionic anhydride, were determined in the selected-ion-monitoring (SIM) mode. The method was validated in the range 0.3-10 microg/mg for EP, 0.06-2.5 microg/mg for PE and NPE and 0.04-1 microg/mg NE and MPE. Mean recovery ranged between 65.7 and 81.3% for the different analytes in dietary supplements. The quantification limits were 0.3 microg/mg for EP, 0.06 microg/mg for PE, 0.04 microg/mg for NPE, NE and MPE. The method was applied to analysis of various dietary supplements containing Ma-huang (Ephedra Sinica) and Sida Cordifolia plant extracts promoted for aiding weight control and boosting sports performance and energy.

An isotopically labeled internal standard liquid chromatography-tandem mass spectrometry method for determination of ephedrine alkaloids and synephrine in dietary supplements

We report a simplified analytical procedure for determination of ephedrine alkaloids and synephrine in dietary supplements. Cleanup by simple filtration, when combined with tandem mass spectrometry (MS/MS) detection, provided results comparable to our published method with solid phase extraction (SPE) cleanup and single-stage MS detection with in-source fragmentation. We also compared three mass spectrometric experimental configurations: electrospray (ESI) and atmospheric pressure chemical ionization (APCI) with MS/MS and APCI-MS with fragmentation provided by increasing cone voltage. Because these methods used one isotopically labeled internal standard to determine several different analytes, quantitation errors may arise from susceptibility to ionization suppression caused by the matrix. We therefore compared the results obtained by ESI and APCI ionization.

Hemodynamic effects of ephedra-free weight-loss supplements in humans

PURPOSE

Ephedra-free weight loss dietary supplements containing bitter orange (Citrus aurantium), a botanical source of the adrenergic amines synephrine and octopamine, have quickly emerged on consumer markets to replace banned ephedra products. These supplements may have some of the health risks associated with ephedra, but studies in humans are lacking. Our aim was to characterize the pharmacokinetics and cardiovascular effects of C. aurantium dietary supplements.

SUBJECTS AND METHODS

Ten healthy adult nonsmokers participated in a randomized, double-blind, placebo-controlled, three-arm crossover study. Single doses of C. aurantium (Advantra Z) containing 46.9 mg synephrine, Xenadrine EFX, a multi-component formulation containing 5.5 mg synephrine, and placebo were administered with a one-week washout.

RESULTS

Compared with placebo, Xenadrine EFX but not Advantra Z increased systolic and diastolic blood pressure with peak changes from baseline at 2 hours of 9.6 +/- 6.2 mm Hg systolic (P = 0.047), and 9.1 +/- 7.8 mm Hg diastolic (P = 0.002). Heart rate was increased from baseline at 6 hours compared with placebo (16.7 beats per minute with Xenadrine EFX, P = 0.011; 11.4 beats per minute with Advantra Z, P = 0.031). Dose-adjusted synephrine pharmacokinetics were similar between treatments with t(max) = 90 min, t(1/2) = 3.0 hours, V/F = 16347 L, and CL/F = 88.9 L/min for Xenadrine EFX.

CONCLUSION

Ephedra-free weight loss supplements have significant cardiovascular stimulant actions, similar to ephedra. These effects are not likely caused by C. aurantium alone, because an eightfold higher dose of synephrine (Advantra Z) had no effect on blood pressure, but may be attributable to caffeine and other stimulants in the multi-component formulation.

Caffeine-herbal ephedra combination increases resting energy expenditure, heart rate and blood pressure

1. The purpose of the present study was to determine whether the consumption of an acute dose of caffeine and Ma Huang increases resting energy expenditure (REE), heart rate (HR) and blood pressure (BP) over a 3 h period. 2. A randomized, double-blind cross-over study was performed evaluating the acute effects of caffeine (150 mg)/herbal ephedra (Ma Huang; 20 mg ephedra alkaloids) versus a placebo. A total of eight healthy subjects (four males and four females) with a mean (+/-SD) age of 23.4+/-0.8 years (mean ages for males and females: 25.3+/-0.7 and 22.0+/-0.7 years, respectively) and 22.5+/-3.1% body fat (15.7+/-1.2 and 27.6+/-3.5% body fat for males and females, respectively) were recruited to the study. Participants were moderate caffeine users (approximately 150-300 mg/day). 3. Subjects reported to the laboratory following a 12 h fast and 48 h of a caffeine-free diet. Resting energy expenditure was measured prior to supplementation and for 15 min every 30 min for 3 h following supplementation. Heart rate and BP were obtained every 15 min. Blood samples were obtained every 30 min following the measurement of REE and analysed for caffeine, ephedrine, free fatty acids and glucose. 4. By 3 h, HR was 22.7+/-5.5% higher (P<0.05) than baseline for the caffeine/ephedra trial compared with 8.9+/-2.2% higher for the placebo group. At 3 h, systolic BP was 9.1+/-2.2% higher (P<0.05) than baseline for the caffeine/ephedra trial compared with only 1.9+/-2.9% different from baseline for the placebo trial. There was no effect of the caffeine/ephedra combination on diastolic BP. Resting energy expenditure during the last 30 min was 4.5+/-2.5% higher in the placebo trial and 10.7+/-2.5% higher (P<0.05) in the caffeine/ephedra trial; REE was 8.5 +/- 2.0% higher (P<0.05) in the caffeine/ephedra trial compared with the placebo trial. Free fatty acids increased over time in the placebo and caffeine/ephedra trials (from 0.5+/-0.05 to 0.63+/-0.05 mEq/L and from 0.48+/-0.06L to 0.8+/-0.05 mEq/L, respectively). 5. Caffeine and herbal ephedra, at doses of 150 mg and 20 mg (ephedrine), respectively, result in a significant elevation in REE, HR and BP. Although significant, the increase in energy expenditure is negligible in terms of weight loss.