Simultaneous determination of 11 alkaloids in rat plasma by LC-ESI-MS/MS and a pharmacokinetic study after oral administration of total alkaloids extracted from Naucleaofficinalis

Characterization of the chemical constituents of Croton crassifolius Geisel extract and plasma pharmacokinetics of 6 terpenoids after oral administration by UPLC-Q/TOF-MS

INTRODUCTION

Croton crassifolius Geisel. (CCG) is a traditional Chinese medicine widely used in South China. It has various pharmacological effects and is often used in treating rheumatoid arthritis and gastric and duodenal ulcers. However, the chemical characteristics and its effective constituents are still scarcely studied.

OBJECTIVE

To determine the phytochemical profile of the CCG extract and to investigate the chemical characteristics of terpenoids extracted from rat plasma following oral administration of CCG extract based on UPLC-Q/TOF-MS. Moreover, six terpenoids in CCG were quantified, and in vivo pharmacokinetic behavior after oral CCG extract was further explored.

RESULTS

In total, 56 terpenoids were tentatively identified in the CCG extract and 16 terpenoids were detected in rat plasma after oral CCG extract. In addition, the contents of six terpenoids in CCG were clarified. The plasma quantification method of six terpenoids was further established, validated, and confirmed to have good sensitivity and specificity. The six analytes exhibited excellent linearity in respective concentration ranges (r ≥ 0.998). The intra-day and inter-day precisions relative standard deviation (RSD, %) were less than 11.27%, and the accuracies ranged from -7.06% to 9.91%. Stability, extraction recovery, and matrix effect in plasma were within the required limits (RSD < 15%).

CONCLUSION

A total of 56 terpenoids were identified in CCG and 16 prototype components in plasma after oral CCG. The validated quantitative method was successfully applied to the simultaneous determination of six major terpenoids in plasma. The pharmacokinetic parameters are clarified, which can guide the clinical application of CCG.

Strictosamide ameliorates LPS-induced acute lung injury by targeting ERK2 and mediating NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Acute lung injury (ALI) ranks among the deadliest pulmonary diseases, significantly impacting mortality and morbidity. Presently, the primary treatment for ALI involves supportive therapy; however, its efficacy remains unsatisfactory. Strictosamide (STR), an indole alkaloid found in the Chinese herbal medicine Nauclea officinalis (Pierre ex Pit.) Merr. & Chun (Wutan), has been found to exhibit numerous pharmacological properties, particularly anti-inflammatory effects.

AIM OF THE STUDY

This study aimes to systematically identify and validate the specific binding proteins targeted by STR and elucidate its anti-inflammatory mechanism in lipopolysaccharide (LPS)-induced ALI.

MATERIALS AND METHODS

Biotin chemical modification, protein microarray analysis and network pharmacology were conducted to screen for potential STR-binding proteins. The binding affinity was assessed through surface plasmon resonance (SPR), cellular thermal shift assay (CETSA) and molecular docking, and the anti-inflammatory mechanism of STR in ALI treatment was assessed through in vivo and in vitro experiments.

RESULTS

Biotin chemical modification, protein microarray and network pharmacology identified extracellular-signal-regulated kinase 2 (ERK2) as the most important binding proteins among 276 candidate STR-interacting proteins and nuclear factor-kappaB (NF-κB) pathway was one of the main inflammatory signal transduction pathways. Using SPR, CETSA, and molecular docking, we confirmed STR's affinity for ERK2. In vitro and in vivo experiments demonstrated that STR mitigated inflammation by targeting ERK2 to modulate the NF-κB signaling pathway in LPS-induced ALI.

CONCLUSIONS

Our findings indicate that STR can inhibit the NF-κB signaling pathway to attenuate LPS-induced inflammation by targeting ERK2 and decreasing phosphorylation of ERK2, which could be a novel strategy for treating ALI.

Two new indole alkaloids from Nauclea officinalis and their evaluation for cytotoxic activities

Two new indole alkaloids, naucleamide H (1) and (±)-19-O-butylangustoline (8), along with seven known alkaloids, 3,14-dihydroangustine (2), (-)-naucleofficine D (3a), (+)-naucleofficine D (3b), nauclefine (4), angustidine (5),19-O-ethylangustoline (6) and angustine (7) were isolated from the water extract of Nauclea officinalis. The structures of these compounds were established by spectroscopic analysis. Among them, the cytotoxicity of 1, 2, 6 and 8 were evaluated against six human cancer cell lines (HepG-2, SKOV3, HeLa, SGC 7901, MCF-7 and KB) in vitro for the first time with 5-fluorouracil as a positive control drug. The new compound 1 had a strong inhibitory effect on the proliferation of HepG-2 with an IC50 value of 19.59 μg/mL. The new compound 8 had a strong inhibitory effect on HepG-2, SKOV3, HeLa, MCF-7 and KB, IC50 value was 5.530, 23.11, 31.30, 32.42 and 37.26 μg/mL, respectively.

Simultaneous determination of abrine, hypaphorine, schaftoside and soyasaponin Bb in rat plasma by UPLC-MS/MS and its application to a pharmacokinetic study after oral administration of Abrus cantoniensis Hance extract

A simple and sensitive liquid chromatography tandem mass spectrometry method was established and validated for the quantitative determination of abrine, hypaphorine, schaftoside and soyasaponin Bb in rat plasma. After preparation by protein precipitation with acetonitrile, the analytes and internal standard were separated on a Waters CORTECS T3 column using acetonitrile containing 0.1% formic acid and 0.1% formic acid in water as mobile phase by gradient elution in 2 min. The method showed excellent linearity over the range of 5-500 ng/ml with acceptable intra- and inter-day precision, accuracy, matrix effect and recovery. The stability assay indicated that the four analytes were stable during the analysis process. The method was applied to a pharmacokinetic study of Abrus cantoniensis Hance in rats. The result suggested that after oral administration, the four analytes were quickly absorbed into the plasma. The dose-normalized exposure of hypaphorine was the highest with a long elimination half-life (t1/2 9.83 h), followed by abrine and schaftoside with t1/2 values of 1.07 and 1.15 h. The dose normalized exposure of soyasaponin Bb was the lowest, which is possibily due to the high polarity and poor permeability. This study provides a basis for elucidating the material foundation of A. cantoniensis Hance.

Non-clinical pharmacokinetics study in rat plasma, tissues and excreta of honokiol derivative HM475 by UPLC-Q-TOF-MS/MS

To provide the basis for further development and research of drugs, non-clinical pharmacokinetics studies were conducted on HM475, which is composed of natural active molecules honokiol and metformin through cyclization. In this paper, HM475 was studied from six aspects by gavage and intraperitoneal injection: 1) Acute toxicity of HM475 in rats, 2) Pharmacokinetic characteristics of HM475 in rats, 3) Distribution characteristics of HM475 in heart, liver, spleen, lung, and kidney, small intestine, fat and brain of rats, 4) Main metabolic pathways of HM475 in rats, 5) Excretion of HM475 in rats, 6) Determination of protein binding rate of HM475 in bovine plasma, rabbit plasma, and rat plasma. Acute toxicity of HM475 on SD rats was evaluated by maximum dose method. The metabolic analysis method of HM475 in rats was first established by UPLC-Q-TOF-MS/MS technology, and the pharmacokinetic characteristics of oral administration and intraperitoneal injection were studied. Experimental results showed that HM475 had no obvious acute toxicity. The absolute oral bioavailability of HM475 was 38.45 %, and the drug concentration in plasma was higher than that in tissues. Combined with the process characteristics of HM475 in vivo, it is inferred that HM475 has enterohepatic circulation. In this study, non-clinical pharmacokinetics were systematically studied to provide data support for the clinical pharmacokinetics and pharmacodynamics of HM475, to more accurately predict the pharmacokinetic behavior of HM475 in human body and provide scientific data for the compound to enter clinical research.

Analysis of the pharmacodynamic difference between Xiaojin Pills taken with Chinese Baijiu and water based on serum pharmacochemistry and pharmacokinetics

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaojin Pills (XJPs), which has the function of dissipating knots and dispersing swelling, removing blood stasis, and relieving pain, is a classic prescription for the treatment of mammary glands hyperplasia. It is also the first choice of Chinese patent medicine for the clinical treatment of mammary glands hyperplasia in contemporary traditional Chinese medicine clinics. Previous studies have shown that the efficacy of XJPs "taken orally after soaked with Chinese Baijiu" in tradition was significantly better than that of taking it orally with water in modern in terms of activating the blood, anti-inflammation, analgesia, anti-mammary gland hyperplasia, anti-breast cancer and its metastasis in vitro and in vivo, especially under low-dose conditions. However, the material basis for the difference in efficacy between XJP&B and XJP&W is still unclear.

AIM OF THE STUDY

To analyze the material basis of the significant difference in efficacy between XJP&B and XJP&W from the perspective of serum pharmacochemistry and pharmacokinetics, and clarified the scientific connotation of XJPs "taken orally after soaked with Chinese Baijiu".

MATERIALS AND METHODS

Ultra-high performance liquid chromatography-mass spectrometry combined with a multivariate statistical analysis method were used to screen the differential components in the Chinese Baijiu extract and the water extract of XJPs and the corresponding residues, so as to clarify the differential components between XJP&B and XJP&W in vitro. The migrating components in the blood after XJP&B and XJP&W were characterized by serum pharmacochemical methods, in order to clarify the differential components in rats. The pharmacokinetic parameters of the representative components absorbed into the blood were compared between XJP&B and XJP&W by the pharmacokinetics study method, in order to determine the dynamic changes of the representative components in rats.

RESULTS

The identification results of different components in vitro showed that there were 34 and 12 different compounds between the Chinese Baijiu extract and water extract of XJPs, and the residues after Chinese Baijiu extraction and water extraction, respectively. The content of different components such as arachidonic acid, ursolic acid, 3-acetyl-11-keto-β-boswellic acid, 2α-hydroxyursolic acid, and oleanolic acid was higher in the Chinese Baijiu extract, which was more than twice the content in the water extract. The results of the serum pharmacochemistry study indicated that 42 prototype components were identified in the serum of rats after XJP&B and XJP&W, including organic acids, alkaloids, steroids, and terpenoids. And XJP&B increased the absorption of the prototype components of organic acids in XJPs into the blood. The pharmacokinetic study results of representative components demonstrated that the mean plasma concentration-time profile and pharmacokinetic parameters of muscone, aconitine, and 3-acetyl-11-keto-β-boswellic acid were significantly different between XJP&B and XJP&W. Compared with XJP&W, the C_max and AUC_0-t of muscone and aconitine in XJP&B were higher, and the T_1/2 and MRT_0-t of 3-acetyl-11-keto-β-boswellic acid in XJP&B were relatively longer.

CONCLUSION

This research proved that "taking XJPs orally after being soaked with Chinese Baijiu" can increase the dissolution and absorption of active ingredients in XJPs, increase the plasma concentration and content of representative ingredients, and prolong its action time, thus enhancing the biological activity of XJPs in vitro and in vivo. To a certain extent, this study revealed the material basis of the significantly better efficacy of XJP&B than XJP&W and clarified the scientific connotation of XJPs "taken orally after soaked with Chinese Baijiu", which can provide a theoretical basis for the optimization of XJPs' clinical administration method.

Strategy for the quality control of herbal preparations made of Sarcocephalus latifolius: Development and validation of a UHPLC-PDA method for quantification of angustoline and strictosamide and chemical profiling using LC-QToF

INTRODUCTION

Sarcocephalus latifolius is one of the most used plants in West African traditional medicine to treat malaria.

OBJECTIVE

The aim is to establish a strategy to control the quality of herbal preparations made from S. latifolius.

METHOD

A UHPLC-PDA method was developed for the determination and quantification of the two main bioactive compounds (angustoline and strictosamide) in various parts of the plant. Additionally, an LC-QToF with electrospray ionization method is described for the identification and confirmation of compounds in samples of different parts of the plant.

RESULTS

With the UHPLC-PDA method, separation was achieved within 5 min using a C18 column stationary phase at a temperature of 45°C and a gradient system with a mobile phase of water and acetonitrile, both containing 0.1% formic acid. The method was validated for linearity, accuracy, precision (repeatability and intermediate precision), limit of detection (LOD), and limit of quantification (LOQ). The LOD and LOQ of angustoline were found to be 0.3 and 0.8 μg/ml, respectively, and those of strictosamide were found to be 0.1 and 0.3 μg/ml, respectively. Using the LC-QToF method, 90 secondary metabolites, including four isolated compounds from the plant's roots, were identified from leaf, bark, and root samples of S. latifolius.

CONCLUSION

This work is the first to propose a strategy to control the quality of herbal preparations made from S. latifolius. The developed method allows the quantification of the main bioactive compounds and the established chemical profile allows to distinguish the plant from any other species.

Measurement of Pharmacokinetics and Tissue Distribution of Four Compounds from Nauclea officinalis in Rat Plasma and Tissues through HPLC-MS/MS

A rapid, sensitive, selective, and accurate HPLC-MS/MS method was developed and validated for the simultaneous determination of chlorogenic acid, naucleactonin C, khaephuoside A 3,4-dimethoxyphenyl-1-O-β-apiofuroseyl(1 ⟶ 2)-β-D-glucopyranoside in rat plasma and tissues after oral administration of Nauclea officinalis extracts. Chloramphenicol was used as an internal standard (IS). The plasma and tissue samples were extracted by protein precipitation with methanol-ethyl acetate (1 : 1, v/v) including 0.1% (v/v) formic acid. The chromatographic separation was achieved by using an C18 column with gradient elution using mobile phase, which consisted of 0.1% formic acid water (A) and acetonitrile (B) and the flow rate of 0.8 mL/min. Mass spectrometric detection was performed in multiple reaction monitoring (MRM) mode utilizing electrospray ionization (ESI) in negative mode. The developed method exhibited good linearity (determination coefficients, R ² ≥ 0.9849), and the lower limits of quantification were 2, 5, 5, and 25 ng/mL for chlorogenic acid, naucleactonin C, khaephuoside A, and 3,4-dimethoxyphenyl-1-O-β-apiofuroseyl(1 ⟶ 2)-β-D-glucopyranoside. The intraday and interday precisions (relative standard deviation, RSD) were less than 12.65%, while the accuracy was ranged from 86.31 to 114.17%. The recovery rate were 51.85-97.06%, 75.99-106.68%, 77.46-105.35%, and 68.36-103.75% for chlorogenic acid, naucleactonin C, khaephuoside A, and 3,4-dimethoxyphenyl-1-O-β-apiofuroseyl(1 ⟶ 2)-β-D-glucopyranoside the matrix effects were 50.17-116.62%, 86.75-115.99%, 45.79-87.44%, and 51.60-92.34% for chlorogenic acid, naucleactonin C, khaephuoside A, and 3,4-dimethoxyphenyl-1-O-β-apiofuroseyl(1 ⟶ 2)-β-D-glucopyranoside in different matrix. The developed method was successfully applied to a pharmacokinetic study and tissue distribution of four compounds in rats after oral administration of Nauclea officinalis extracts.

Nauclea officinalis: A Chinese medicinal herb with phytochemical, biological, and pharmacological effects

Nauclea officinalis (N. officinalis), a medicinal plant of the genus Nauclea in the family Rubiaceae, is used in the treatment of fever, pneumonia, pharyngolaryngitis, and enteritis in China. Extracts of N. officinalis include alkaloids, phenolic acids, pentacyclic triterpenoids, and flavonoids, which exert all kinds of pharmacological effects, for instance anti-inflammatory, anti-tumor, antibacterial, and antiviral and therefore show good effectiveness. To gain a comprehensive and deep understanding, the medicinal chemistry and chemical biology of N. officinalis are summarized in this review to provide a theoretical basis. The pharmacological effects were reviewed to provide evidence or insights into potential opportunities for further studies and medicinal exploitation of N. officinalis.

The rapid profiling and simultaneous determination of 12 major alkaloids in Nauclea officinalis by UPLC-Q-TOF-MS and HPLC-ESI-MS/MS

For the first time, we determined the phytochemical profile of alkaloids from N. officinalis using ultraperformance liquid chromatography-quadrupole-time-of-flight-tandem mass spectrometry (UPLC-Q-TOF-MS/MS). A rapid, specific, and sensitive high-performance liquid chromatography-tandem mass spectrometry method was subsequently developed and fully validated for the simultaneous determination of 12 major alkaloid constituents in N. officinalis: pumiloside; naucleoxoside A; naucleoxoside B; nauclefine; angustidine; angustoline; (3S,19S)-3,14-dihydroangustoline ([α]20D: (-)191°); (3S,19R)-3,14-dihydroangustoline ([α]20D: (-)294.7°); strictosamide; angustine; vincosamide; and 3,14-dihydroangustine. The analytes were detected with an electrospray ionization (ESI) source and multiple reaction monitoring (MRM) using positive scanning mode. Three pairs of epimers (naucleoxoside A and naucleoxoside B; (3S,19S)-3,14-dihydroangustoline ([α]20D: (-)191°) and (3S,19R)-3,14-dihydroangustoline ([α]20D: (-)294.7°); and strictosamide and vincosamide) were successfully separated using an ACQUITY UPLC® BEH C₁₈ column (2.1 mm × 100 mm, 1.7 μm) at 30 °C, with a gradient mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B), a flow rate of 0.2 mL min^-1, and a total run time of 30 min. All calibration curves exhibited excellent linear regression (r > 0.999) within the test range. The precision, repeatability, and stability of the method toward the 12 alkaloid compounds were less than 2.0% in terms of the relative standard deviation (RSD) values. The mean recoveries for all compounds were between 98.7% and 101.1%, with RSD values ranging from 0.55% to 1.7% for N. officinalis samples.