An integrated strategy for establishment of metabolite profile of endogenous lysoglycerophospholipids by two LC-MS/MS platforms

Excipient-related impurities in liposome drug products

Liposomes are widely used in the pharmaceutical industry as drug delivery systems to increase the efficacy and reduce the off-target toxicity of active pharmaceutical ingredients (APIs). The liposomes are more complex drug delivery systems than the traditional dosage forms, and phospholipids and cholesterol are the major structural excipients. These two excipients undergo hydrolysis and/or oxidation during liposome preparation and storage, resulting in lipids hydrolyzed products (LHPs) and cholesterol oxidation products (COPs) in the final liposomal formulations. These excipient-related impurities at elevated concentrations may affect liposome stability and exert biological functions. This review focuses on LHPs and COPs, two major categories of excipient-related impurities in the liposomal formulations, and discusses factors affecting their formation, and analytical methods to determine these excipient-related impurities.

Combinatory data-independent acquisition and parallel reaction monitoring method for revealing the lipid metabolism biomarkers of coronary heart disease and its comorbidities

Disorders of lipid metabolism are a common cause of coronary heart disease (CHD) and its comorbidities. In this study, ultra-performance liquid chromatography-high-resolution mass spectrometry in data-independent acquisition (DIA) mode was applied to collect abundant tandem mass spectrometry data, which provided valuable information for lipid annotation. For the lipid isomers that could not be completely separated by chromatography, parallel reaction monitoring (PRM) mode was used for quantification. A total of 223 plasma lipid metabolites were annotated, and 116 of them were identified for their fatty acyl chain composition and location. In addition, 152 plasma lipids in patients with CHD and its comorbidities were quantitatively analyzed. Multivariate statistical analysis and metabolic pathway analysis demonstrated that glycerophospholipid and sphingolipid metabolism deserved more attention for CHD. This study proposed a method combining DIA and PRM for high-throughput characterization of plasma lipids. The results also improved our understanding of metabolic disorders of CHD and its comorbidities, which can provide valuable suggestions for medical intervention.

An integrated strategy for the establishment of a protoberberine alkaloid profile: Exploration of the differences in composition between Tinosporae radix and Fibraurea caulis

INTRODUCTION

Accurate species and content identification of major active components in herbals are the guarantee of the safety and effectiveness for medical and commodity purposes.

OBJECTIVES

In this study, an integrated strategy used to establish the protoberberine alkaloid profile was applied to explore the differences in composition between the pieces of Tinosporae radix and Fibraurea caulis, both of which had morphological similarities.

MATERIALS AND METHODS

First, an in-house library including possible protoberberine alkaloids based on different substituents was predicted by systematic literature survey. Meanwhile, diagnostic fragments of protoberberine alkaloids were investigated using the corresponding standards. Second, ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was used to obtain multidimensional mass spectral data. Then, the identifications were confirmed by targeted filter of the acquired data based on the library.

RESULTS

As a result, 10 protoberberine alkaloid molecules including 46 isomers were identified or characterised. The qualitative distribution and relative content of protoberberine alkaloids revealed the fundamental difference between Tinosporae radix and Fibraurea caulis. 25 alkaloids were present in both herbals, while five compounds were detected only in Tinosporae radix. Furthermore, the contents of four alkaloids in Tinosporae radix were significantly higher than those in its adulterant, Fibraurea caulis.

CONCLUSION

The five unique ingredients in Tinosporae radix can be used as a better indicator for distinguishing the pieces of Tinosporae radix and Fibraurea caulis. The protoberberine alkaloid profile established in this study can be applied to quality evaluation of the two herbals or other herbals containing major protoberberine alkaloids.

Potential hypoglycemic metabolites in dark tea fermented by Eurotium cristatum based on UPLC-QTOF-MS/MS combining global metabolomic and spectrum-effect relationship analyses

The preventive and therapeutic effects of dark tea fermented by Eurotium cristatum (DTE) in glucose metabolism have been demonstrated. However, few studies have investigated comprehensive changes in the chemical composition and activity in DTE before and after fermentation. In this study, the metabolic profiling of raw samples and fermented samples was determined by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). Furthermore, a systematic analytical strategy combining global metabolomics and the spectrum-effect relationship based on α-glucosidase inhibition was employed for screening discriminant metabolites. As a result, 15 discriminant metabolites were identified in DTE samples. Among them, 10 metabolites (4 fatty acids, 1 dyphylline derivative, 3 lysophosphatidylcholines, and 2 triterpenes) increased in relative contents and the contents of the other 5 polyphenol metabolites decreased after fermentation. These metabolites were critical constituents possibly associated with DTE's hypoglycemic activity, which also might be suitable as quality evaluation indicators. This study provided a worthy insight into the exploration of representative active constituents or quality indicators of DTE.

Analytical Methodologies for Lipidomics in Hemp Plant

The chemical composition of Cannabis sativa L. has been extensively studied for tens of years, but little is known about its lipidome. This chapter describes an analytical workflow for polar lipid determination in hemp. After extraction, lipids are enriched and isolated by graphitized carbon black sorbent, and the isolated lipid is analyzed by liquid chromatography (LC) coupled with high resolution mass spectrometry, leading to identification of many lipid species. We have developed a semi-automated platform using commercially available Lipostar software for lipid identification. Our approach affords the identification of 189 polar lipids in hemp extract, including sulfolipids and phospholipids. The number of the identified lipid species is by far the highest ever reported for Cannabis sativa.

Screening of lipid metabolism biomarkers in patients with coronary heart disease via ultra-performance liquid chromatography-high resolution mass spectrometry

Coronary heart disease (CHD) has a high mortality worldwide. This study aimed to screen lipid metabolism biomarkers in patients with coronary heart disease via ultra-performance liquid chromatography-high resolution mass spectrometry. Extraction and reconstitution solvents, liquid chromatographic and mass spectrometry conditions were optimized to detect more plasma lipid metabolites. In this study, the chromatographic and mass spectra characteristics of lipid metabolites were summarized. A total of 316 lipid metabolites were annotated via diagnostic fragment ion filtration, nitrogen rule filtration, and neutral loss filtration. Glycerophospholipid metabolism and sphingolipid metabolism were revealed as the main lipid disorders of CHD. This study provides a novel insight for high-throughput detection of lipid metabolites in plasma and provides a further understanding of the occurrence of CHD, which can provide valuable suggestions for the prevention of CHD.

Qualitative distribution of endogenous phosphatidylcholine and sphingomyelin in serum using LC-MS/MS based profiling

PCs and SMs are the major types of glycerophospholipids and sphingophospholipids, the two main categories of phospholipids (PLs). To study the qualitative distribution of serum phosphatidylcholine (PC) and sphingomyelin (SM) in human and three rodent species, liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap-MS/MS) was used to identify them comprehensively through the accurate mass measurement of both precursor ions and their corresponding product ions. Based on the fragmentation rules of standards, the product ions at m/z 184.0733 were filtered to maximally screen possible PC and SM molecules. For PC, the fatty acid at sn-1 and sn-2 of the glycerol backbone was identified based on the product ions in negative mode. A total of 91 PCs and 31 SMs molecular species, consisting of 166 PCs and 39 SMs regioisomers, were detected in human serum, which is the most comprehensive identification of PC and SM species in serum. The qualitative distributions of PC in rat and SM in golden hamster, respectively, were more similar with that of human from an overall perspective. Those results provided guidance regarding to the animal model selection for mimicking lipid related-syndromes or diseases in human.

The hypoglycemic effect of extract/fractions from Fuzhuan Brick-Tea in streptozotocin-induced diabetic mice and their active components characterized by LC-QTOF-MS/MS

Fuzhuan Brick-Tea is a postfermented product with the hypoglycemic effect, which is prepared from the leaves of Camellia sinensis var. sinensis. However, the material basis associated with the hypoglycemic effect was not clear. The present research was designed to explore the hypoglycemic effect of extract/fractions from Fuzhuan Brick-Tea in streptozotocin-induced type II diabetic mice. Then an ultra-high pressure liquid chromatography along with quadrupole time of flight mass spectrometry was used to analyze the phytochemicals in Fuzhuan Brick-Tea fractions. As a result, the hypoglycemic and hypolipidemic effects were evidently observed from the serum biochemical indexes and liver pathological examination in type II diabetic mice. In addition, there were total of 20 major components including eight lysophosphatidylcholines (Lyso-PCs), five fatty acids, and seven novel theophylline derivatives tentatively identified in the active fraction from water extract. Therefore, these components were assumed to contribute partly to the hypoglycemic effect of Fuzhuan Brick-Tea. These findings also give the evidence that the Lyso-PCs, fatty acids, and novel theophylline derivatives in Fuzhuan Brick-Tea may provide benefits in ameliorating disorders of glucose and lipid metabolism. PRACTICAL APPLICATION: This study suggests that the Lyso-PCs, fatty acids, and novel theophylline derivatives in Fuzhuan Brick-Tea may provide benefits in ameliorating disorders of glucose and lipid metabolism. It can be taken as a beneficial diet additive or nutraceutical.

The metabolic change in serum lysoglycerophospholipids intervened by triterpenoid saponins from Kuding tea on hyperlipidemic mice

Triterpenoid saponins from Kuding tea have demonstrated preventive effects on hyperlipidaemia induced by a high-fat diet. Lysoglycerophospholipids (Lyso-GPLs) are known to be associated with proatherogenic conditions such as hyperlipidaemia. In this study, a target profiling strategy based on a multiple reaction monitoring mode was applied for the analysis of Lyso-GPLs. The metabolic changes were evaluated by the qualitative and relative quantitative distribution of six classes of Lyso-GPLs in mouse serum. A total of 153 Lyso-GPL regioisomers, consisting of 85 lysophosphatidylcholines, 15 lysophosphatidic acids, 23 lysophosphatidylethanolamines, 5 lysophosphatidylserines, 19 lysophosphatidylinositols and 6 lysophosphatidylglycerols, were detected and quantified. The results showed decreased trends in the content of total Lyso-GPLs in the serum of hyperlipidemic mice compared with that in normal controls. The content of total Lyso-GPLs significantly increased after treatment with triterpenoid saponins from Kuding tea. Among them, the proportions of most Lyso-GPLs with a higher degree of unsaturation or a longer carbon chain in fatty acyl chains dramatically decreased in hyperlipidemic mice. However, this tendency reversed after the treatment of triterpenoid saponins from Kuding tea. This is the first study regarding a target profiling strategy for the quantitative analysis of six different types of Lyso-GPLs on high-fat diet-induced hyperlipidemic mice intervened by Kuding tea. Those Lyso-GPLs changed significantly may be potential biomarkers for hyperlipidaemia, and involved in the mechanism of the preventive intervention of Kuding tea on Lipid metabolic diseases.

Clinical lipidomics in understanding of lung cancer: Opportunity and challenge

Disordered lipid metabolisms have been evidenced in lung cancer as well as its subtypes. Lipidomics with in-depth mining is considered as a critical member of the multiple omics family and a lipid-specific tool to understand disease-associated lipid metabolism and disease-specific dysfunctions of lipid species, discover biomarkers and targets for monitoring therapeutic strategies, and provide insights into lipid profiling and pathophysiological mechanisms in lung cancer. The present review describes the characters and patterns of lipidomic profiles in patients with different lung cancer subtypes, important values of comprehensive lipidomic profiles in understanding of lung cancer heterogeneity, urgent needs of standardized methodologies, potential mechanisms by lipid-associated enzymes and proteins, and the importance of integration between clinical phenomes and lipidomic profiles. The characteristics of lipidomic profiles in different lung cancer subtypes are extremely varied among study designs, objects, methods, and analyses. Preliminary data from recent studies demonstrate the specificity of lipidomic profiles specific for lung cancer stage, severity, subtype, and response to drugs. The heterogeneity of lipidomic profiles and lipid metabolism may be part of systems heterogeneity in lung cancer and be responsible for the development of drug resistance, although there are needs for direct evidence to show the existence of intra- or inter-lung cancer heterogeneity of lipidomic profiles. With an increasing understanding of expression profiles of genes and proteins, lipidomic profiles should be associated with activities of enzymes and proteins involved in the processes of lipid metabolism, which can be profiled with genomics and proteomics, and to provide the opportunity for the integration of lipidomic profiles with gene and protein expression profiles. The concept of clinical trans-omics should be emphasized to integrate data of lipidomics with clinical phenomics to identify disease-specific and phenome-specific biomarkers and targets, although there are still a large number of challenges to be overcome in the integration between clinical phenomes and lipidomic profiles.

Lysophospholipid profiles of apolipoprotein E-deficient mice reveal potential lipid biomarkers associated with atherosclerosis progression using validated UPLC-QTRAP-MS/MS-based lipidomics approach

Lysophospholipids (Lyso-PLs) are lipid-derived signaling molecules which were demonstrated to have a strong correlation with the progression of atherosclerosis. In this study, we investigated the influence of high-fat diet on Lyso-PL profiles of atherosclerosis-prone apolipoprotein E-deficient (ApoE^-/-) mice and wild type C57BL/6 J mice to find out the potential biomarkers associated with atherosclerosis. Firstly, the quantitative profiling method for Lyso-PLs based on ultra-performance liquid chromatography-quadrupole linear ion trap mass spectrometry (UPLC-QTRAP-MS/MS) was established and validated. Secondly, this method was utilized to quantify 169 targeted Lyso-PLs in plasma samples of ApoE^-/- mice and wild type C57BL/6 J mice collected at different time points. Finally, 12 of 37 differential Lyso-PLs were identified as more reliable biomarkers by integrating static metabolomics and time-dependent analyses, among which Lyso-PC/15:0, 18:1/Lyso-PI, 22:5/Lyso-PI and 22:4/Lyso-PI were highly correlated with TCand LDL-C levels. Meanwhile, we found that the Lyso-PL profiles of ApoE^-/- mice and C57BL/6 J mice were distinguished by altered metabolism of different Lyso-PLs classes, while C57BL/6 J mice fed with high-fat diet and normal diet were discriminated by the content differences of Lyso-PLs with same fatty acid composition. In conclusion, these results provided detailed changes of Lyso-PL profiles associated with atherosclerosis and the differential Lyso-PLs with reasonable change trends may serve as promising biomarkers for atherosclerosis progression.