Determination of α-methylenecyclopropylglycine in Shahi and China litchi cultivars at three different maturity stages: A quantitative study using liquid chromatography tandem mass spectrometry.

This study presents the contents of α-methylenecyclopropylglycine, a potentially toxic amino acid, in the peel, pulp and seed fractions of two well-known litchi varieties, namely Shahi and China, over a span of three harvest-seasons. For analysing α-methylenecyclopropylglycine, an LC-MS/MS-based method was validated. The method-accuracies fell within 75-110 % (RSD, <15 %) at 0.1 mg/kg (LOQ) and higher levels. A comparative evaluation of the results in peel, pulp and seed at 30 days before harvest (DBH), 15-DBH, and edible-ripe stage revealed that α-methylenecyclopropylglycine content increased as the litchi seeds grew towards maturity, regardless of the cultivar. In arils, at maturity, the concentration of α-methylenecyclopropylglycine ranged from not-detected to 11.7 µg/g dry weight. The Shahi cultivar showed slightly higher α-methylenecyclopropylglycine content in comparison to China litchi. This paper presents the first known analysis of combined seasonal data on different fruit components at various growth stages for the two chosen litchi cultivars grown in India.

Application of Proteomics Technology Based on LC-MS Combined with Western Blotting and Co-IP in Antiviral Innate Immunity.

As an interferon-stimulating factor protein, STING plays a role in the response and downstream liaison in antiviral natural immunity. Upon viral invasion, the immediate response of STING protein leads to a series of changes in downstream proteins, which ultimately leads to an antiviral immune response in the form of proinflammatory cytokines and type I interferons, thus triggering an innate immune response, an adaptive immune response in vivo, and long-term protection of the host. In the field of antiviral natural immunity, it is particularly important to rigorously and sequentially probe the dynamic changes in the antiviral natural immunity connector protein STING caused by the entire anti-inflammatory and anti-pathway mechanism and the differences in upstream and downstream proteins. Traditionally, proteomics technology has been validated by detecting proteins in a 2D platform, for which it is difficult to sensitively identify changes in the nature and abundance of target proteins. With the development of mass spectrometry (MS) technology, MS-based proteomics has made important contributions to characterizing the dynamic changes in the natural immune proteome induced by viral infections. MS analytical techniques have several advantages, such as high throughput, rapidity, sensitivity, accuracy, and automation. The most common techniques for detecting complex proteomes are liquid chromatography (LC) and mass spectrometry (MS). LC-MS (Liquid Chromatography-Mass Spectrometry), which combines the physical separation capability of LC and the mass analysis capability of MS, is a powerful technique mainly used for analyzing the proteome of cells, tissues, and body fluids. To explore the combination of traditional proteomics techniques such as Western blotting, Co-IP (co-Immunoprecipitation), and the latest LC-MS methods to probe the anti-inflammatory pathway and the differential changes in upstream and downstream proteins induced by the antiviral natural immune junction protein STING.

Identifying an Abnormal Phosphorylated Adaptor by Viral Kinase Using Mass Spectrometry.

Mass spectrometers are widely used to identify protein phosphorylation sites. The process usually involves selective isolation of phosphoproteins and subsequent fragmentation to identify both the peptide sequence and phosphorylation site. Immunoprecipitation could capture and purify the protein of interest, greatly reducing sample complexity before submitting it for mass spectrometry analysis. This chapter describes a method to identify an abnormal phosphorylated site of the adaptor protein by a viral kinase through immunoprecipitation followed by LC-MS/MS.

Evidence to support cultivated fruiting body of Ophiocordyceps sinensis (Ascomycota)'s role in relaxing airway smooth muscle.

ETHNOPHARMACOLOGICAL RELEVANCE: Ophiocordyceps sinensis (O. sinensis) is a genus of Ascomycete fungus that is endemic to the alpine meadows of the Tibetan Plateau and adjoining Himalayas. It has been used traditionally as a tonic to improve respiratory health in ancient China as well as to promote vitality and longevity. Bioactive components found in O. sinensis such as adenosine, cordycepin, 3-deoxyadenosine, L-arginine and polysaccharides have gained increasing interest in recent years due to their antioxidative and other properties, which include anti-asthmatic, antiviral, immunomodulation and improvement of general health. AIM OF THE STUDY: This study's primary aim was to investigate the effect of a cultivated fruiting body of O. sinensis strain (OCS02®) on airways patency and the secondary focus was to investigate its effect on the lifespan of Caenorhabditis elegans. MATERIALS AND METHODS: A cultivated strain, OCS02®, was employed and the metabolic profile of its cold-water extract (CWE) was analysed through liquid chromatography-mass spectrometry (LC-MS). Organ bath approach was used to investigate the pharmacological properties of OCS02® CWE when applied on airway tissues obtained from adult male Sprague-Dawley rats. The airway relaxation mechanisms of OCS02® CWE were explored using pharmacological tools, where the key regulators in airway relaxation and constriction were investigated. For the longevity study, age-synchronised, pos-1 RNAi-treated wild-type type Caenorhabditis elegans at the L4 stage were utilised for a lifespan assay. RESULTS: Various glycopeptides and amino acids, particularly a high concentration of L-arginine, were identified from the LC-MS analysis. In airway tissues, OCS02® CWE induced a significantly greater concentration-dependent relaxation when compared to salbutamol. The relaxation response was significantly attenuated in the presence of NG-Nitro-L-arginine methyl ester (L-NAME), 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ) and several K+ channel blockers. The longevity effect induced by OCS02® CWE (5 mg/mL and above) was observed in C. elegans by at least 17%. CONCLUSIONS: These findings suggest that the airway relaxation mechanisms of OCS02® CWE involved cGMP-dependent and cGMP-independent nitric oxide signalling pathways. This study provides evidence that the cultivated strain of OCS02® exhibits airway relaxation effects which supports the traditional use of its wild O. sinensis in strengthening respiratory health.

Direct analysis in real time mass spectrometry (DART-MS/MS) for rapid urine opioid detection in a clinical setting.

BACKGROUND AND AIMS: Current laboratory methods for opioid detection involve an initial screening with immunoassays which offers efficient but non-specific results and a subsequent liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmation which offers accurate results but requires extensive sample preparation and turnaround time. Direct Analysis in Real Time (DART) tandem mass spectrometry is evaluated as an alternative approach for accurate opioid detection with efficient sample preparation and turnaround time. MATERIALS AND METHODS: DART-MS/MS was optimized by testing the method with varying temperatures, operation modes, extraction methods, hydrolysis times, and vortex times. The method was evaluated for 12 opioids by testing the analytical measurement range, percent carryover, precision studies, stability, and method-to-method comparison with LC-MS/MS. RESULTS: DART-MS/MS shows high sensitivity and specificity for the detection of 6-acetylmorphine, codeine, hydromorphone, oxymorphone, hydrocodone, naloxone, buprenorphine, norfentanyl, and fentanyl in urine samples. However, its performance was suboptimal for norbuprenorphine, morphine and oxycodone. CONCLUSION: In this proof-of-concept study, DART-MS/MS is evaluated for its rapid quantitative definitive testing of opioids drugs in urine. Further research is needed to expand its application to other areas of drug testing.

Global Metabolomics Using LC-MS for Clinical Applications.

Metabolomics can be used for a multitude of purposes, including monitoring of treatment effects and for increasing the knowledge of the pathophysiology of a wide range of diseases. Global (commonly referred to as "untargeted") metabolomics is hypothesis-generating and provides the opportunity to discover new biomarkers. Being versatile and having a high degree of selectivity and sensitivity, liquid chromatography-mass spectrometry (LC-MS) is the most common technique applied for metabolomics. We here present our global metabolomics LC-electrospray ionization-MS/MS method. The sample preparation procedures for plasma, serum, dried blood spots, urine, and cerebrospinal fluid are simple and nonspecific to reduce the risk of analyte loss. The method is based on reversed-phase chromatography using a diphenyl column. The high-resolution Q Exactive Orbitrap MS with data-dependent acquisition provides MS/MS spectra of a wide range of analytes. Our method covers a large part of the metabolome regarding hydrophobicity and compound class.

Distinguishing Artifactual Fatty Acid Dimers from Fatty Acid Esters of Hydroxy Fatty Acids in Untargeted LC-MS Pipelines.

Untargeted metabolomics is a powerful profiling tool for the discovery of possible biomarkers of disease onset and progression. Analytical pipelines applying liquid chromatography (LC) and mass spectrometry (MS)-based methods are widely used to survey a broad range of metabolites within various metabolic pathways, including organic acids, amino acids, nucleosides, and lipids. Accurate and complete identification of putative metabolites is an ongoing challenge in untargeted metabolomics studies. Highly sensitive instrumentation can result in the detection of adduct and fragment ions that form reproducibly and contain identifiable ions that are difficult to distinguish from metabolic pathway intermediates, which may result in false-positive identification. At concentrations as low as 10 µM, free fatty acids have been found to form homo- and heterodimers in untargeted metabolomics pipelines that resemble the lipid class fatty acid esters of hydroxy fatty acids (FAHFAs), resulting in misidentification. This chapter details a protocol for LC-MS-based untargeted metabolomics using hydrophilic interaction chromatography (HILIC) that specifically aids in distinguishing artifactual fatty acid dimers from endogenous FAHFAs.

LC-MS/MS Quantification of Endocannabinoids in Tissues.

Endocannabinoids (ECBs) are lipid-derived endogenous molecules with important physiological roles such as regulation of energy balance, immunity, or neural development. Quantitation of ECBs helps better understand their physiological role and modulation of biological processes. This chapter presents the simultaneous quantification of 14 ECBs and related molecules in the brain, liver, and muscle, as well as white and brown adipose tissue using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The dynamic range of the method has been tuned to cover the endogenous concentrations of these analytes given the fact that they are endogenously present at different orders of magnitude. Specifically, three groups are established: 0.5-5000 ng/mL for 2-oleoyl- and 2-linoleoylglycerol and arachidonic acid, 0.05-500 ng/mL for 2-arachidonoylglycerol, and 0.0005-0.5 ng/mL for anandamide, palmitoyl-, palmitoleoyl-, stearoyl-, oleoyl-, linoleoyl-, alpha-linolenoyl-, dihomo-gamma-linolenoyl-, docosahexaenoyl-, and pentadecanoylethanolamide.

Mobile Phase Contaminants Affect Neutral Lipid Analysis in LC-MS-Based Lipidomics Studies.

Lipidomics is a well-established field, enabled by modern liquid chromatography mass spectrometry (LC-MS) technology, rapidly generating large amounts of data. Lipid extracts derived from biological samples are complex, and most spectral features in LC-MS lipidomics data sets remain unidentified. In-depth analyses of commercial triacylglycerol, diacylglycerol, and cholesterol ester standards revealed the expected ammoniated and sodiated ions as well as five additional unidentified higher mass peaks with relatively high intensities. The identities and origin of these unknown peaks were investigated by modifying the chromatographic mobile-phase components and LC-MS source parameters. Tandem MS (MS/MS) of each unknown adduct peak yielded no lipid structural information, producing only an intense ion of the adducted species. The unknown adducts were identified as low-mass contaminants originating from methanol and isopropanol in the mobile phase. Each contaminant was determined to be an alkylated amine species using their monoisotopic masses to calculate molecular formulas. Analysis of bovine liver extract identified 33 neutral lipids with an additional 73 alkyl amine adducts. Analysis of LC-MS-grade methanol and isopropanol from different vendors revealed substantial alkylated amine contamination in one out of three different brands that were tested. Substituting solvents for ones with lower levels of alkyl amine contamination increased lipid annotations by 36.5% or 27.4%, depending on the vendor, and resulted in >2.5-fold increases in peak area for neutral lipid species without affecting polar lipid analysis. These findings demonstrate the importance of solvent selection and disclosure for lipidomics protocols and highlight some of the major challenges when comparing data between experiments.

Development of an advanced analytical technique for detecting multiple pesticide residues in vegetables through liquid chromatography tandem mass spectroscopy (LC-MS/MS).

A comprehensive LC-MS/MS method, which employs Positive Electrospray Ionization (PEI) and Multiple Reaction Monitoring (MRM) was developed for the simultaneous determination of 35 pesticides belonging to various chemical classes in tomato, brinjal, chili, and okra samples. Extraction was facilitated using a modified QuEChERS method, which allows efficient sample analysis in a single run. Calibration curves for each pesticide exhibited linearity within the concentration range of 0.0025 to 0.1 µg mL-1, with correlation coefficients ranging from 0.993 to 0.999. Mean recoveries at five fortification levels (0.01 to 0.5 µg kg-1) ranged from 80 to 90%, demonstrating satisfactory precision (RSD < 20%). The matrix effects, mitigated through an optimized cleanup process, were observed within the range of 6.42% to 19.52%. The developed method having the limit of quantification of 0.01 mg kg-1 for all 35 pesticides, proved to be highly sensitive and rapid for multi-residue estimation in diverse vegetable samples. Subsequently, the method was used to analyze the market samples from Varanasi, India, which revealed the presence of pesticides like Chlorpyrifos, Chlorantraniliproleand Indoxacarb in tomato, brinjal, chili and okra. Therefore, the method could be considered as a robust tool for monitoring pesticide residues in vegetables, aiding in quality assessment and regulatory compliance in the agriculture sector.

Screening Proteins That Interact With AcHog1 and the Functional Analysis of AcSko1 in Aspergillus cristatus.

Aspergillus cristatus is a dominant fungus formed during the "flowering" process of Fuzhuan brick tea. Previous research has established that the sporulation of Aspergillus nidulans, a model organism of filamentous fungi, is regulated by light. However, the sporulation of A. cristatus is dependent on osmotic stress. In a previous study, we used pull-down and mass spectrometry to identify proteins that interacted with AcHog1 in A. cristatus when cultured under different conditions of osmotic stress. In the present study, we analyzed the proteins we identified previously to investigate their functional role. The AA1E3BER4 protein was located downstream of Hog1 in the HOG branch pathway and was identified that was regulated by AcHog1. Furthermore, yeast two-hybrid analysis showed that AA1E3BER4 interacted with AcHog1. In addition, we knocked out and complemented the Acsko1 gene encoding the AA1E3BER4 protein. We found that the number of sexual and asexual spores were downregulated by 3.81- and 4.57-fold, respectively, in the ΔAcsko1 strain. The sensitivity of the ΔAcsko1 strain to sorbitol and sucrose, as regulators of osmotic stress, increased, and the sensitivity to high sucrose was higher than that of sorbitol. Acsko1 also regulated the response of A. cristatus to oxidative stress, Congo red, and SDS (sodium dodecyl sulfate). In addition, the deletion of Acsko1 significantly increased the pigment of the ΔAcsko1 strain. This is the first study to report the role of the sko1 gene in oxidative stress, stress-induced damage to the cell wall, and pigment in Aspergillus cristatus.

Characterization of host cell proteins in the downstream process of plant-Based biologics using LC-MS profiling.

Host cell proteins (HCPs) are process-related impurities found in biopharmaceutical products that can impair their safety and efficacy. While ELISA has traditionally been employed to quantify HCPs, LC-MS emerges as a powerful alternative for precise identification of individual HCPs. In this study, we used LC-MS for profiling HCPs from Nicotiana benthamiana-derived biopharmaceuticals. Our approach involved rigorous false discovery rate control to ensure data integrity and reliability. Comprehensive analysis revealed a systematic reduction of HCPs following purification, demonstrating the efficiency of purification processes in removing non-essential proteins. Furthermore, LC-MS enabled the identification of potential contaminants, refining purification strategies and improving product purity and integrity. Our findings highlight the potential of LC-MS as an analytical tool for HCPs analysis in biopharmaceutical development and manufacturing. By providing detailed insights into HCPs profiles and contaminants, LC-MS facilitates informed decision-making in downstream processing steps, benefiting product quality, patient safety, and the biopharmaceutical sector.

Analysis of tetrahydroisoquinolines formed after simultaneous consumption of ethanol and amphetamine or its derivatives by LC-MS/MS in human blood, brain, and liver tissue.

The effects of the simultaneous consumption of amphetamine or amphetamine derivatives and alcohol have not yet been adequately clarified, particularly concerning potential condensation products resulting from the endogenous reaction between these substances and their metabolites (e.g., acetaldehyde, a metabolite of ethanol). In this study, we developed an LC-MS/MS method employing liquid-liquid extraction for the qualitative detection of some relevant condensation products belonging to the class of tetrahydroisoquinolines and their derivatives in human blood, brain, and liver samples. This includes the analysis of the substrates amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyamphetamine, as well as the condensation products 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, N-methyl-1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, 1,3-dimethyl-7,8-methylenedioxy-1,2,3,4-tetrahydroisoquinoline, and N-methyl-1,3-dimethyl-7,8-methylenedioxy-1,2,3,4-tetrahydroisoquinoline. Therefore, the reference standards of the mentioned tetrahydroisoquinolines were synthesized in advance and the method was validated with regard to the question of the qualitative detection of these compounds. The validation parameters included selectivity, specificity, limit of detection, lower limit of quantification, recovery, matrix effects, and stability for blood, brain, and liver samples. Following the analysis of human blood and post-mortem tissue samples, evidence of the condensation product 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline originating from the interaction between amphetamine and acetaldehyde was identified in two liver samples. On the contrary, no evidence of this or other tetrahydroisoquinolines was found in the remaining tissue and serum samples.

Metabolome and Transcriptome Profiling Reveals Age-Associated Variations in Meat Quality and Molecular Mechanisms of Taihe Black-Bone Silky Fowls.

To explore the changes in meat quality and molecular mechanisms during the growth and development of Taihe black-bone silky fowl, this study employed liquid chromatography-mass spectrometry (LC-MS/MS) metabolomics to elucidate the dynamic changes of key differential metabolites (DMs) affecting meat quality, indicating that chicken at D120 had higher levels of ω-3 polyunsaturated fatty acids (PUFAs), creatine, anserine, and homocarnosine, while D150 had the most stachydrine and D210 had the most acylcarnitines. Additionally, D120 and D180 had more umami and sweet compounds. Furthermore, key metabolic pathways influenced by age included purine metabolism, the pentose phosphate pathway, nicotinate and nicotinamide metabolism, and taurine and hypotaurine metabolism. Transcriptomic identified differential expression genes (DEGs) are predominantly enriched in focal adhesion, the TGF-ß signaling pathway, and the MAPK signaling pathway. Integrated metabolomics and transcriptomics revealed complex regulatory networks of DEGs and DMs in key metabolic pathways. This research enhanced our understanding of the biology of Taihe black-bone silky fowl meat quality, revealing possible biomarkers.

Influence of sex and functional status on the value of serum steroid profiling in discriminating adrenocortical carcinoma from adrenocortical adenoma.

Background: It is challenging for clinicians to distinguish adrenocortical carcinoma (ACC) from benign adrenocortical adenomas (ACA) in their early stages. This study explored the value of serum steroid profiling as a complementary biomarker for malignancy diagnosis of ACC other than diameter and explored the influence of sex and functional status. Methods: In this retrospective study, a matched cohort of patients diagnosed with either ACC or ACA based on histopathology was meticulously paired in a 1:1 ratio according to sex, age, and functional status. Eight serum steroids including 11-deoxycortisol, 11-deoxycorticosterone, progesterone, androstenedione, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), 17-hydroxyprogesterone, and estradiol, were quantified by liquid chromatography tandem mass spectrometry. We conducted a comparative analysis of the clinical characteristics and serum steroid profiles of patients with ACC and ACA, with further subgroup analysis. Results: The study included 31 patients with ACC and 31 matched patients with ACA. Patients with ACC exhibited significantly larger tumor diameters, lower body mass index (BMI), and higher levels of 11-deoxycortisol, progesterone, and androstenedione than those with ACA. 11-deoxycortisol was the only valuable index for discriminating ACC from ACA, regardless of functional status and sex. Progesterone, DHEA, and DHEAS levels were higher in the functional ACC group than in the non-functional ACC group. Female ACC patients, especially in postmenopausal female exhibited higher levels of androstenedione than male patients. The area under the curve of tumor diameter, 11-deoxycortisol, and BMI was 0.947 (95% CI 0.889-1.000), with a sensitivity of 96.8% and specificity of 90.3%. Conclusion: Serum steroid profiling serves as a helpful discriminative marker for ACC and ACA, with 11-deoxycortisol being the most valuable marker. For other steroid hormones, consideration of sex differences and functional status is crucial.

Elucidating the effective age for dietary restriction and the key metabolites involved.

Dietary restriction (DR) extends lifespan in various species, but its effect at different ages, especially when started later, is unclear. This study used Caenorhabditis elegans to explore the impact of DR at different ages. Worms were divided into control and DR groups, with daily survival monitored. To confirm the occurrence of DR, the expression of DR-sensitive genes namely acdh-1, pyk-1, pck-2 and cts-1 were determined using RT-qPCR. Liquid chromatography mass spectrometry (LC-MS) was employed to observe the changes in metabolites affected by DR. The results indicated that young worms subjected to mild DR displayed the longest lifespan, highlighting the effectiveness of initiating DR at a young age. Increased expression of acdh-1 and pck-2 suggests activation of beta-oxidation and gluconeogenesis, while decreased cts-1 expression indicates a reduced citric acid cycle, further supporting the observed effects of DR in these worms. Metabolomic results indicated that DR decreased the activity of mechanistic Target of Rapamycin (mTOR) and the synthesis of amino acids namely leucine, tyrosine and tryptophan to conserve energy for cell repair and survival. DR also decreased levels of N-acetyl-L-methionine and S-adenosyl-methionine (SAM) in methionine metabolism, thereby promoting autophagy, reducing inflammation, and facilitating the removal of damaged cells and proteins. In conclusion, initiating dietary restriction early in life extends the lifespan by modulating amino acid metabolism and enhancing the autophagy pathway, thereby maintaining cellular wellbeing.

Buffer-free high pH mobile phase LC-MS/MS for determination of the alcohol biomarker phosphatidylethanol 16:0/18:1 and 20 drugs and metabolites in whole blood.

BACKGROUND: Acidic mobile phases are commonly used in reversed phase liquid chromatography tandem mass spectrometry (LC-MS/MS) bioanalysis. However, increased sensitivity, improved peak symmetry, and increased retention, especially for basic hydrophilic drugs have been observed using basic mobile phases. In our previous acidic mobile phase LC-MS/MS method we needed two injections (0.4 and 2.0 µL) of each sample for this task, which is inefficient. The aim of this study was to investigate if basic mobile phase LC-MS/MS could be used to determine phosphatidylethanol 16:0/18:1 and 20 other drugs and metabolites with satisfactory sensitivity in one single run. METHODS: Whole blood was prepared by 96-well supported-liquid extraction using heptane/ethyl acetate/2-propanol (16:64:20, v:v:v). Chromatographic separation was achieved on an Acquity BEH C18 column (50 × 2.1 mm I.D.), using a mobile phase with 0.025 % ammonia, pH 10.7 (Solvent A) and methanol (Solvent B). All compounds had isotope-labelled internal standards. RESULTS: The method was fully validated. Recovery was between 63 and 91 % for 20 compounds and 10 % for benzoylecgonine. Matrix effects were low, except for ion enhancement of buprenorphine and ion suppression for THC. However, internal standards compensated for these effects. Inter-assay precision and accuracy were < ± 20 % for all compounds at five tested concentrations, except for methamphetamine at the highest concentration. CONCLUSION: An LC-MS/MS method for simultaneous determination of PEth 16:0/18:1 and 20 drugs and metabolites in whole blood were for the first time developed and validated. Retention of PEth 16:0/18:1 was, in contrast to the other 20 compounds, largely affected by mobile phase buffer concentration. The buffer free basic mobile phase ensured that phosphatidylethanol 16:0/18:1 eluted before most of the unwanted phospholipids.

LC-MS coupled with diagnostic ion strategy facilitated the discovery of 5-methylcoumarin meroterpenoids from Gerbera piloselloides.

Plant-derived natural products remain crucial in drug development. However, the identification of undescribed natural products is becoming increasingly challenging. A comprehensive strategy combining LC-MS with diagnostic ions was proposed for the discovery of undescribed 5-methylcoumarin meroterpenoids. Thirteen undescribed 5-methylcoumarin meroterpenoids, including five pairs of enantiomers (1a/1b and 5a/5b-8a/8b), were isolated from the whole plant of Gerbera piloselloides. Their structures and absolute configurations were unambiguously determined based on their spectroscopic data, calculated and experimental ECD data and X-ray diffraction analysis. Bioassays conducted on scopolamine-induced injury PC12 cells revealed that compounds 5a/5b, 7a/7b and 8a/8b possessed mild protective effects. Additionally, compounds 2 and 8 showed notable IL-6 inhibition in lipopolysaccharide-induced BEAS-2B cells.

Liquid-Liquid Extraction Solvent Selection for Comparing Illegal Drugs in Whole Blood and Dried Blood Spot with LC-MS/MS.

AIM: This study focused on the simultaneous detection of amphetamine, 3,4-methyl enedioxy methamphetamine, morphine, benzoylecgonine, and 11-nor-9-carboxy- tetrahydrocannabinol (Δ9-THC-COOH) in whole blood and DBS. It is aimed to select a solvent mixture for liquid-liquid extraction (LLE) technique employing LC-MS/MS. The obtained DBS results were compared with the whole blood samples results. METHODS: A simple, rapid, and reliable LC-MS/MS method was developed and validated for all analytes in whole blood and DBS. LC was performed on a Hypersil Gold C18 column an initial step with a gradient of 0.01 % formic acid, 5 mM ammonium format buffer in water, and acetonitrile at 0.3 ml/min with 7.5-min runtime. RESULTS: A methanol:acetonitrile (40:60 v/v) mixture was selected for both matrices. LOQ values were 10-25 ng/mL; linear ranges were LOQ-500 ng/ml for all analytes; correlation coefficients were greater than 0.99, and all calibrator concentrations were within 20%. Analytical recovery in blood and DBS ranged from 84.9-113.2% of the expected concentration for both intra and-inter day. Analytes were stable for 1, 10, and 30 days after three freeze/thaw cycles. It was determined that the variances of the results obtained with the two matrices in the comparison study were equal for each analyte, and the results were highly correlated (r=0.9625). CONCLUSION: A sensitive, accurate, and reliable chromatographic method was developed to determine amphetamine, MDMA, morphine, benzoylecgonine, and cannabis, by performing the same preliminary steps with whole blood and dried blood spots. It was observed that the results obtained in these two matrices were compatible and interchangeable when statistically compared.

Pharmacokinetics and related gender difference studies of four active components of Codonopsis Pilosula by LC-MS/MS determination.

ETHNOPHARMACOLOGICAL RELEVANCE: Codonopsis pilosula (C. pilosula), commonly known as Dangshen in Chinese, had been used to regulate the immune, digestive, and circulatory systems of human. The reported pharmacokinetic studies on C. pilosula are mainly limited to in vivo profile studies of a single component. It has not been detected simultaneously the in vivo pharmacokinetic profiles of multiple active components as well as related gender difference after oral dosing of the extraction of C. pilosula. AIM OF THE STUDY: This study aims to reveal the pharmacokinetic characteristics of the four main active components of C. pilosula after oral dosing of its extraction in rats, and to explain the gender differences in absorption and metabolism. MATERIALS AND METHODS: The plasma pharmacokinetic characteristics of four main active components of C. pilosula was explored using the established LC-MS/MS method after oral dosing of the extraction of C. pilosula in male and female rats. In vitro intestinal pouch permeability and liver microsome metabolic stability were also observed to classify the possible mechanism of gender difference existed in the pharmacokinetic profiles of the four active components in rats. RESULTS: Four effective components were absorbed quickly in rats after oral administration of alcoholic extract of C. pilosula (1.36 g/mL, equivalent to 2 g/mL as crude drug), and their exposure order was as follows: Atractylenolide III > Lobetyolin > Tangshenoside I > Syringin. The exposure (AUC) and peak concentration (Cmax) of Atractylenolide III in female rats were much higher than those in male rats, indicating a significant gender difference in pharmacokinetics of Atractylenolide III between female and male animals. With the help of the rat model of intestinal sac in vitro, it was found that Lobetyolin was a hypertonic compound, and both Tangshenoside I and Syringin were compounds with medium permeabiltiy. Notably, the Papp of Atractylenolide III was 3.3×10-6 cm/s in male rat intestinal sac assay, while that was 10×10-6 cm/s in female rat intestinal sac model, showing a significant gender difference in intestinal permeability (P<0.05). After the addition of NADPH, the four compounds were reduced in a time-dependent manner, suggesting that CYP450s could catalyze their metabolism. After incubation, the remaining content of Atractylenolide III in the liver microsomes of male and female rats was 27% and 57%, respectively, suggesting slower metabolic rate of in female rat liver microsomes. CONCLUSION: A simple, efficient and reliable LC-MS/MS method for the simultaneous determination of four active index components of C. pilosula, Lobetyolin, Tangshenoside I, Atractylenolide III and Syringin, in rat plasma was established and verified. This method was successfully applied in the pharmacokinetic study after single oral administration of the alcoholic extract of C. pilosula in rats. Gender difference was observed in the pharmacokinetic profile of Atractylenolide III in rats. Intestinal absorption and liver metabolism might be two key factors that resulted in the gender difference in exposure and pharmacokinetics of Atractylenolide III in rats. This study provides supportive data for clinical rational application of C. pilosula in individualized medication therapy.