No significant change of N6 -methyladenosine modification landscape in mouse brain after morphine exposure.

OBJECTIVES: N6 -methyladenosine (m6 A) plays a crucial role in regulating neuroplasticity and different brain functions at the posttranscriptional level. However, it remains unknown whether m6 A modification is involved in acute and chronic morphine exposure. MATERIALS AND METHODS: In this study, we conducted a direct comparison of m6 A levels and mRNA expression of m6 A-associated factors between morphine-treated and nontreated C57BL/6 wild-type mice. We established animal models of both acute and chronic morphine treatment and confirmed the rewarding effects of chronic morphine treatment using the conditioned place preference (CPP) assay. The activation status of different brain regions in response to morphine was assessed by c-fos staining. To assess overall m6 A modification levels, we employed the m6 A dot blot assay, while mRNA levels of m6 A-associated proteins were measured using a quantitative polymerase chain reaction (qPCR) assay. These analyses were performed to investigate whether and how m6 A modification and m6 A-associated protein expression will change following morphine exposure. RESULTS: The overall m6 A methylation and mRNA levels of m6 A-associated proteins were not significantly altered in brain regions that were either activated or not activated during acute morphine stimulation. Similarly, the overall m6 A modification and mRNA levels of m6 A-associated proteins remained unaffected in several key brain regions associated with reward following chronic morphine exposure. CONCLUSION: This study showed that the overall m6 A modification level and mRNA expression levels of m6 A-associated factors were not affected after acute and chronic morphine exposure in different brain regions, indicating m6 A modification may not be involved in brain response to morphine exposure.

A rare case of giant hepatic angiomyolipoma with subcapsular rupture.

Hepatic angiomyolipoma (HAML) is a rare mesenchymal neoplasm that predominantly affects middle-aged women. In this study, we present a case of a 49-year-old woman with a giant HAML accompanied by spontaneous subcapsular rupture. The patient initially experienced nausea and abdominal distention, followed by an enlargement of the upper abdominal circumference. Laboratory examination revealed decreased serum hemoglobin, while tumor biomarkers were within normal ranges. Imaging studies, such as abdominal ultrasound and contrast-enhanced computed tomography (CT), demonstrated a large upper abdominal mass with heterogeneous density and hypervascularity. The tumor appeared to have invaded the left liver, raising concerns about possible malignancy. Subsequent positron-emission tomography/CT confirmed increased fluorodeoxyglucose uptake in the mass. Laparoscopic exploration revealed a protruding, well-encapsulated tumor from the left liver, exhibiting subcapsular hemorrhage. Surgical resection of the tumor and the left liver was performed, leading to a successful outcome.

UHPLC-MS/MS analysis of cAMP and cGMP in rat plasma as potential biomarkers of Yin-Yang disharmony in traditional Chinese medicine.

Cyclic 3',5'-adenosine monophosphate (cAMP) and cyclic 3',5'-guanosine monophosphate (cGMP) are considered as potential biomarkers for Yin-Yang disharmony in traditional Chinese medicine. However, phosphodiesterase-mediated ex vivo degradation of these molecules in biological samples may result in their underestimation. In the present study, a ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for determination of cAMP and cGMP in rat plasma, with special consideration of their stability ex vivo. Following precipitation of proteins from plasma samples with 0.4 M perchloric acid, the analytes were chromatographed on a Shimadzu Shim-pack-XR-ODS II column with 2.5 mM ammonium acetate and methanol in gradient mode. The MS/MS detection was performed using multiple reaction monitoring in the positive electrospray ionization mode. The lower limit of quantification was 0.27 ng/mL for cAMP and 0.37 ng/mL for cGMP. The method was used to determine the plasma cAMP and cGMP levels in normal and Yin deficiency diabetic rats treated with or without Rehmannia glutinosa. The developed method may be useful for evaluating the regulatory effects of Chinese herbal medicine on the levels of cAMP and cGMP in the body.

Rapid determination of seven bioactive components in rat plasma by UPLC-MS/MS and its application to pharmacokinetic compatibility study of Jinlingzi San.

Jinlingzi San (JLZS), composed of Fructus Toosendan (FT) and Rhizoma Corydalis (RC), is a classical traditional Chinese medicine prescription for regulating Qi to relieve pain. The present study investigated the pharmacokinetic compatibility of FT and RC in JLZS. A fast, selective and sensitive UPLC-MS/MS method for simultaneous determination of one limonoid (toosendanin), four tertiary alkaloids (corydaline, tetrahydropalmatine, tetrahydrocoptisine, tetrahydroberberine) and two quaternary alkaloids (palmatine, dehydrocorydaline) in rat plasma was established and fully validated. The plasma samples were pretreated by a fast protein precipitation and chromatographed using a 1.7-µm C18 column and 0.1 % formic acid-water and acetonitrile via gradient elution with a run time of 3.7 min. Multiple reaction monitoring mode with positive electrospray ionization was adopted to detect the analytes and internal standard (diphenhydramine). The lower limits of quantification were 0.08-3.09 ng/mL using only 50 µL of plasma sample. Using the proposed method, the pharmacokinetic differences of seven bioactive components in rats after administration of JLZS and the single herb (FT or RC) were investigated. The results showed that the elimination of toosendanin and alkaloids decreased significantly in the JLZS group (p < 0.05) compared with the single herb group, and the exposure of the alkaloids increased in some degree. The study demonstrated the synergistic effect of combining FT with RC on the pharmacokinetics of seven bioactive components and provided new information for a better understanding of the compatibility mechanism of JLZS.

UHPLC-MS/MS analysis of cAMP and cGMP in rat plasma as potential biomarkers of Yin-Yang disharmony in traditional Chinese medicine / 药物分析学报

Cyclic 3',5'-adenosine monophosphate (cAMP) and cyclic 3',5'-guanosine monophosphate (cGMP) are considered as potential biomarkers for Yin-Yang disharmony in traditional Chinese medicine.However,phosphodiesterase-mediated ex vivo degradation of these molecules in biological samples may result in their underestimation.In the present study,a ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for determination of cAMP and cGMP in rat plasma,with special consideration of their stability ex vivo.Following precipitation of proteins from plasma samples with 0.4 M perchloric acid,the analytes were chromatographed on a Shimadzu Shim-pack-XR-ODS Ⅱ column with 2.5 mM ammonium acetate and methanol in gradient mode.The MS/MS detection was performed using multiple reaction monitoring in the positive electrospray ionization mode.The lower limit of quantification was 0.27 ng/mL for cAMP and 0.37 ng/mL for cGMP.The method was used to determine the plasma cAMP and cGMP levels in normal and Yin deficiency diabetic rats treated with or without Rehmannia glutinosa.The developed method may be useful for evaluating the regulatory effects of Chinese herbal medicine on the levels of cAMP and cGMP in the body.

Optimisation for simultaneous determination of iridoid glycosides and oligosaccharides in Radix Rehmannia by microwave assisted extraction and HILIC-UHPLC-TQ-MS/MS.

Hydrophilic iridoid glycosides and oligosaccharides are the major active ingredients of Radix Rehmanniae. Analysis of oligosaccharides is a challenging task because they are highly hydrophilic, with similar chemical structures and absence of chromophore and fluorophore groups. The difficulty for simultaneous analysis of iridoid glycosides and oligosaccharides in Radix Rehmanniae is increased due to the polarity difference between the two types of ingredients. OBJECTIVE: To develop a method for simultaneous determination of iridoid glycosides (ajugol, catalpol) and oligosaccharides (sucrose, melibiose, raffinose, mannotriose and stachyose) in Radix Rehmanniae. METHODOLOGY: Microwave-assisted extraction (MAE) was established to extract target analytes from Radix Rehmanniae samples using methanol-water (60:40, v/v) as the extraction solvent. Fast separation of seven analytes was achieved by hydrophilic interaction liquid chromatography (HILIC) using an Accucore-150-Amide-HILIC column. Sensitive and selective detection of the analytes was performed by triple quadrupole tandem mass spectrometry (TQ-MS/MS) using multiple reaction monitoring in positive electrospray ionisation mode. RESULTS: Good linearities were achieved for all the analytes with the correlation coefficients above 0.9991. The precisions resulted in deviations of less than 5.0% and the recoveries ranged from 93.8% to 105.5%. The established method was successfully applied to the analysis of iridoid glycosides and oligosaccharides in 12 samples of crude and processed Radix Rehmanniae. CONCLUSION: A simple, rapid and sensitive method based on MAE combined with HILIC-UHPLC-TQ-MS/MS was developed for simultaneous determination of iridoid glycosides and oligosaccharides in Radix Rehmanniae for the first time. The method exhibited excellent performance with simple sample preparation, short analysis time, high selectivity and sensitivity.

Intracellular Accumulation as an Indicator of Cytotoxicity to Screen Hepatotoxic Components of Chelidonium majus L. by LC-MS/MS.

A novel strategy was developed to identify hepatotoxic compounds in traditional Chinese medicines (TCMs). It is based on the exposure of HL-7702 cells to a TCM extract, followed by the identification and further determination of potential hepatotoxic compounds accumulated in the cells by liquid chromatography-tandem mass spectrometry (LC-MS/MS). As a case study, potential hepatotoxic components in Chelidonium majus L. were screened out. Five alkaloids (sanguinarine, coptisine, chelerythrine, protopine, and chelidonine) were identified by LC-MS/MS within 10 min, and their intracellular concentrations were first simultaneously measured by LC-MS/MS with a run time of 4 min. A cell viability assay was performed to assess the cytotoxicity of each alkaloid. With their higher intracellular concentrations, sanguinarine, coptisine, and chelerythrine were identified as the main hepatotoxic constituents in Ch. majus. The study provides a powerful tool for the fast prediction of cytotoxic components in complex natural mixtures on a high-throughput basis.