Liquid chromatography-mass spectrometry method for discovering the metabolic markers to reveal the potential therapeutic effects of naringin on osteoporosis

Integrated non-targeted metabolomics and network pharmacology to reveal the mechanisms of berberine in the long-term treatment of PTZ-induced epilepsy

AIMS

The increasing resistance to anti-seizure medications (ASMs) and the ambiguous mechanisms of epilepsy highlight the pressing demand for the discovery of pioneering lead compounds. Berberine (BBR) has received significant attention in recent years within the field of chronic metabolic disorders. However, the reports on the treatment of epilepsy with BBR are not systematic and the mechanism remains unclear.

MAIN METHODS

In this study, the seizure behaviors of mice were recorded following subcutaneous injection of pentetrazol (PTZ). Non-targeted metabolomics was used to analyze the serum metabolites based on ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). Meanwhile, multivariate statistical methods were used for metabolite identification and pathway analysis. Furthermore, network pharmacology, molecular docking, and quantitative real-time PCR assay were used for the target identification.

KEY FINDINGS

BBR had anti-seizure effects on PTZ-induced seizure mice after long-term treatment. Tryptophan metabolism and phenylalanine metabolism were involved in regulating the therapeutic effects of BBR.

SIGNIFICANCE

This study reveals the potential mechanism of BBR for epilepsy treatment based on non-targeted metabolomics and network pharmacology, which provides evidence for uncovering the pathogenesis of epilepsy, suggesting that BBR is a potential lead compound for anti-epileptic treatment.

Untargeted Metabolite Profiling of Adipose Tissue in Rats Exposed to Mepiquat

Mepiquat (Mep) is a contaminant produced by Maillard reaction with reducing sugar, free lysine and an alkylating agent under typical roasting conditions, particularly in the range of 200-240 °C. It has been reported that exposure to Mep is harmful to rats. However, its metabolic mechanism is still not clear. In this study, untargeted metabolomics was used to reveal the effect of Mep on the metabolic profile of adipose tissue in Sprague-Dawley rats. Twenty-six differential metabolites were screened out. Eight major perturbed metabolic pathways were found, which were linoleic acid metabolism, Phenylalanine, tyrosine, and tryptophan biosynthesis, phenylalanine metabolism, arachidonic acid metabolism, Glycine, serine, and threonine metabolism, glycerolipid metabolism, Alanine, aspartate, and glutamate metabolism, and glyoxylate and dicarboxylic acid metabolism. This study lays a solid foundation for clarifying the toxic mechanism of Mep.

Plasma metabolomic characterization of premature ovarian insufficiency

BACKGROUND

Premature ovarian insufficiency (POI) patients are predisposed to metabolic disturbances, including in lipid metabolism and glucose metabolism, and metabolic disorders appear to be a prerequisite of the typical long-term complications of POI, such as cardiovascular diseases or osteoporosis. However, the metabolic changes underlying the development of POI and its subsequent complications are incompletely understood, and there are few studies characterizing the disturbed metabolome in POI patients. The aim of this study was to characterize the plasma metabolome in POI by using ultrahigh-performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) metabolomics and to evaluate whether these disturbances identified in the plasma metabolome relate to ovarian reserve and have diagnostic value in POI.

METHODS

This observational study recruited 30 POI patients and 30 age- and body mass index (BMI)-matched controls in the Center for Reproductive Medicine, Department of Gynecology and Obstetrics, Nanfang Hospital, Southern Medical University, from January 2018 to October 2020. Fasting venous blood was collected at 9:00 am on days 2-4 of the menstrual cycle and centrifuged for analysis. An untargeted quantitative metabolomic analysis was performed using UHPLC-MS/MS.

RESULTS

Our study identified 48 upregulated and 21 downregulated positive metabolites, and 13 upregulated and 48 downregulated negative metabolites in the plasma of POI patients. The differentially regulated metabolites were involved in pathways such as caffeine metabolism and ubiquinone and other terpenoid-quinone biosynthesis. Six metabolites with an AUC value > 0.8, including arachidonoyl amide, 3-hydroxy-3-methylbutanoic acid, dihexyl nonanedioate, 18-HETE, cystine, and PG (16:0/18:1), were correlated with ovarian reserve and thus have the potential to be diagnostic biomarkers of POI.

CONCLUSION

This UHPLC-MS/MS untargeted metabolomics study revealed differentially expressed metabolites in the plasma of patients with POI. The differential metabolites may not only be involved in the aetiology of POI but also contribute to its major complications. These findings offer a panoramic view of the plasma metabolite changes caused by POI, which may provide useful diagnostic and therapeutic clues for POI disease.

Development of approach for flavonoid profiling of biotechnological raw materials Iris sibirica L. by HPLC with high-resolution tandem mass spectrometry

INTRODUCTION

Iris L. are promising in medicine due to the biological activity of extracts. Iris sibirica L. is spread in Russia but its phytochemical composition has not been studied in detail though it is included in the Red Book. For this reason, I. sibirica L. biotechnology is in high demand. One of the key points in biotechnology is the regulation of plant metabolism using phytohormones. Obtaining of chromatographic metabolite profiles allows to control this process.

OBJECTIVE

The aim of this study was to develop an approach for effective control of biotechnological raw materials of I. sibirica L. by flavonoid profiles using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and to investigate the influence of phytohormones in nutrient media on content of flavonoids.

METHODOLOGY

Iris sibirica L. regenerated plants were grown on Murashige-Skoog media with 6-benzylaminopurine (6-BAP) and α-naphtylacetic acid (NAA) additives. To optimise extraction conditions, the design of the experiment was used. Profiles of polyphenols were obtained by HPLC-MS/MS in the positive and negative ionisation modes.

RESULTS

The process for efficient extraction from leaves of I. sibirica L. were developed. The factors influencing the extraction efficiency of flavonoids have been determined. A total of 36 compounds were identified by HPLC-MS/MS. Among them isoflavones and their glycosides are the main classes. Addition of an auxin-like hormone increased the non-polar flavonoid levels, but decreased the polar ones. The variation in concentration of cytokinin (6-BAP) affected almost all of the analytes.

CONCLUSION

The methodology for effective control of I. sibirica L. raw plant material biotechnology was developed by analysing obtained chromatographic polyphenol profiles.

Application of metabolomics in osteoporosis research

Osteoporosis (OP) is a systemic disease characterized by bone metabolism imbalance and bone microstructure destruction, which causes serious social and economic burden. At present, the diagnosis and treatment of OP mainly rely on imaging combined with drugs. However, the existing pathogenic mechanisms, diagnosis and treatment strategies for OP are not clear and effective enough, and the disease progression that cannot reflect OP further restricts its effective treatment. The application of metabolomics has facilitated the study of OP, further exploring the mechanism and behavior of bone cells, prevention, and treatment of the disease from various metabolic perspectives, finally realizing the possibility of a holistic approach. In this review, we focus on the application of metabolomics in OP research, especially the newer systematic application of metabolomics and treatment with herbal medicine and their extracts. In addition, the prospects of clinical transformation in related fields are also discussed. The aim of this study is to highlight the use of metabolomics in OP research, especially in exploring the pathogenesis of OP and the therapeutic mechanisms of natural herbal medicine, for the benefit of interdisciplinary researchers including clinicians, biologists, and materials engineers.