UPLC-Q-TOF/MS based metabolomic profiling of serum and urine of hyperlipidemic rats induced by high fat diet

Noninvasive Urinary Biomarkers for Obesity-Related Metabolic Diseases: Diagnostic Applications and Future Directions

Obesity-related metabolic diseases include conditions linked to obesity, such as type 2 diabetes, hypertension, steatotic liver disease, and polycystic ovary syndrome. These disorders are primarily caused by insulin resistance, chronic inflammation, and excessive fat accumulation. They represent significant health challenges and often remain asymptomatic during their early stages. Traditional diagnostic tools, including blood glucose, lipid levels, blood pressure, and uric acid measurements, provide valuable insights but fall short of fully capturing the complexity of metabolic dysfunction. Consequently, there is a growing need for noninvasive, easily accessible biomarkers, especially those found in urine, to enable more accurate, sensitive, and patient-friendly diagnostic methods. Urine, with its diverse range of metabolites that reflect the body's metabolic changes, is an ideal sample for early detection. Recent advancements in urine metabolomics and proteomics have highlighted the potential of urinary biomarkers for diagnosing obesity-related metabolic diseases. Despite challenges such as the need for standardized detection techniques and clinical validation, the integration of artificial intelligence and multi-omics approaches holds significant promise for enhancing diagnostic accuracy and advancing disease management strategies.

Identification of serum metabolite biomarkers and metabolic reprogramming mechanisms to predict recurrence in cholangiocarcinoma

Cholangiocarcinoma (CCA) has high recurrence rates that severely limit long-term survival. Effective tools for accurate recurrence monitoring and diagnosis remain lacking. Metabolic reprogramming, a key driver of CCA growth and recurrence, is underutilized in cancer screening and management. This study aimed to identify metabolite-based biomarkers to evaluate recurrence severity, enhance disease management, and elucidate the molecular mechanisms underlying CCA recurrence. A comprehensive, non-targeted serum metabolomics analysis using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was conducted. Support Vector Machine (SVM) modeling was employed to develop a predictive framework based on metabolite biomarkers. The analysis revealed significant alterations in metabolomics and lipidomics across CCA recurrence subtypes. Notably, changes in metabolites such as amino acids, lipid-derived carnitines, and glycerophospholipids were associated with cancer progression through enhanced energy production and lipid remodeling. The SVM-constructed metabolite-based predictive model demonstrated predictive accuracy comparable to current clinical diagnostic standards. These findings provide novel insights into the metabolic mechanisms underlying CCA recurrence, addressing critical clinical challenges. By advancing early diagnostic approaches, particularly for preoperative detection, this study offers a reliable method for predicting recurrence in CCA patients. This enables effective treatment planning and supports the development of personalized therapeutic strategies, ultimately improving patient outcomes.

Skin Metabolic Signatures of Psoriasis and Psoriasis Concurrent with Metabolic Syndrome

Purpose

Psoriasis is a complex inflammatory skin disorder that is closely associated with metabolic syndrome (MetS). Limited information is available on skin metabolic changes in psoriasis; the effect of concurrent MetS on psoriatic skin metabolite levels is unknown. We aimed to expand this information through skin metabolomic analysis.

Patients and Methods

Untargeted metabolomics was conducted using skin samples from 38 patients with psoriasis vulgaris with MetS (PVMS), 23 patients with psoriasis vulgaris without MetS (PVNMS), and 10 healthy controls (HC). Data analyses, including multivariate statistical analysis, KEGG pathway enrichment analysis, correlation analysis, and receiver operating characteristic curve analysis, were performed.

Results

Significant discrepancies were found between skin metabolites in the HC and PVNMS groups, particularly those involved in nucleotide and glycerophospholipid metabolism. Fifteen of these metabolites were positively correlated with psoriasis severity. Furthermore, MetS was found to affect the metabolic profiles of patients with psoriasis. There were some metabolites with consistent alterations in both the PVNMS/HC and PVMS/PVNMS comparisons.

Conclusion

This study may provide new insights into the link between skin metabolism and psoriatic inflammation and the mechanism underlying the interaction between psoriasis and MetS.

A systematic evaluation of quenching, extraction and analysis procedures for metabolomics study of the mechanism of QYSLD intervention in A549 cells

The preparation of cellular metabolomics samples and how to achieve comprehensive coverage of different polar metabolites in cell samples in the analysis pose a challenge for cellular metabolomics. In this study, we optimized a metabolomics protocol based on ultra-high-performance liquid chromatography high-resolution mass spectrometry (UPLC/HRMS) for the extraction and detection of metabolites in A549 cells and exploration of the intervention effect of Qi-Yu-San-Long decoction (QYSLD) on A549 cells. The results indicate that the lowest level of ATP leakage was observed when A549 cells were quenched under liquid nitrogen. MeOH/chloroform/H2O (1:2:1) extraction yielded more chromatographic peaks and excellent reproducibility, and the relative extraction efficiency of most target metabolites was also high. And we optimized the chromatographic separation conditions in both HILIC and RPLC modes, enabling comprehensive detection and analysis of metabolites with varying polarities. Then, we applied the optimized method to UPLC-Q-TOF/MS-based metabolomics of A549 cells to study the mechanism of QYSLD intervention in non-small cell lung cancer (NSCLC). The CCK-8, EdU staining, and cell cycle assay showed that QYSLD inhibited the proliferation of A549 cells by interfering with the cell cycle and blocking them in the G1 phase. A total of 36 differential metabolites associated with the antitumor effects of QYSLD on NSCLC were identified, mainly involving nicotinate and nicotinamide metabolism, sphingolipid metabolism, and glycerophospholipid metabolism. And western blotting confirmed that the change in 1-methylnicotinamide levels after QYSLD intervention was associated with the inhibition of nicotinamide N-methyltransferase expression in A549 cells.

Potential Beneficial Effects of Crab-Flavored Seafood Intake in Young Rats

Background

Crab-flavored seafood is a well-known traditional Japanese product that is sold as "imitation crab" worldwide. Although it is a low-cost, low-fat, high-protein food, there are few data on its potential health benefits. Here, we have assessed the effects of crab-flavored seafood consumption on organ weight and serum biomarkers levels in rats.

Methods

Sprague-Dawley rats (male; aged 6 weeks) were fed a normal diet (n = 8) or a normal diet with 5% dried crab-flavored seafood (n = 8) for 84 days. Food intake and overall body weight were measured every week; organ weight and blood biochemistry were evaluated at the end of the administration period.

Results

After 84 days, there were no significant differences in food intake, overall body weight, or organ weight between the 2 groups; however, the muscle weight of rats fed crab-flavored seafood tended to be higher than that of rats fed the normal diet. Several serum biomarkers did not differ between the 2 groups, but serum high-density lipoprotein, total bilirubin, and indirect bilirubin levels were significantly raised in rats fed crab-flavored seafood. Moreover, blood urea nitrogen was significantly lower, and some liver function parameters tended to be lower in rats fed crab-flavored seafood.

Conclusions

Consumption of crab-flavored seafood may be effective for promoting muscle protein synthesis and improving serum biomarkers associated with disorders such as cardiovascular disease and stroke. Thus, crab-flavored seafood may have application as a functional food for the global management of human health.

The Application of Metabolomics in Hyperlipidemia: Insights into Biomarker Discovery and Treatment Efficacy Assessment

Hyperlipidemia is a lipid metabolism disorder that refers to increased levels of total triglycerides (TGs), cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C) and decreased levels of high-density lipoprotein-cholesterol (HDL-C). It is a major public health issue with increased prevalence and incidence worldwide. The ability to identify individuals at risk of this disorder before symptoms manifest will facilitate timely intervention and management to avert potential complications. This can be achieved by employing metabolomics as an early detection method for the diagnostic biomarkers of hyperlipidemia. Metabolomics is an analytical approach used to detect and quantify metabolites. This provides the ability to explain the metabolic processes involved in the development and progression of certain diseases. In recent years, interest in the use of metabolomics to identify disease biomarkers has increased, and several biomarkers have been discovered, such as docosahexaenoic acid, glycocholic acid, citric acid, betaine, and carnitine. This review discusses the primary metabolic alterations in the context of hyperlipidemia. Furthermore, we provide an overview of recent studies on the application of metabolomics to the assessment of the efficacy of traditional herbal products and common lipid-lowering medications.

Beneficial effects of Lactobacillus rhamnosus hsryfm 1301 fermented milk on rats with nonalcoholic fatty liver disease

A growing stream of research suggests that probiotic fermented milk has a good effect on nonalcoholic fatty liver disease. This work aimed to study the beneficial effects of Lactobacillus rhamnosus hsryfm 1301 fermented milk (fermented milk) on rats with nonalcoholic fatty liver disease induced by a high-fat diet. The results showed that the body weight and the serum levels of total cholesterol, total glyceride, low-density lipoprotein, alanine transaminase, aspartate aminotransferase, free fatty acid, and reactive oxygen species were significantly increased in rats fed a high-fat diet (M) for 8 wk, whereas high-density lipoprotein cholesterol and superoxide dismutase were significantly decreased. However, the body weight and the serum levels of total cholesterol, total glyceride, alanine transaminase, aspartate aminotransferase, free fatty acid, reactive oxygen species, interleukin-8, tumor necrosis factor-α, and interleukin-6 were significantly decreased with fermented milk (T) for 8 wk, and the number of fat vacuoles in hepatocytes was lower than that in the M group. There were significant differences in 19 metabolites in serum between the M group and the C group (administration of nonfermented milk) and in 17 metabolites between the T group and the M group. The contents of 7 different metabolites, glycine, glycerophosphocholine, 1,2-dioleoyl-sn-glycero-3-phosphocholine, thioetheramide-PC, d-aspartic acid, oleic acid, and l-glutamate, were significantly increased in the M group rat serum, and l-palmitoyl carnitine, N6-methyl-l-lysine, thymine, and 2-oxadipic acid were significantly decreased. In the T group rat serum, the contents of 8 different metabolites-1-O-(cis-9-octadecenyl)-2-O-acetyl-sn-glycero-3-phosphocholine, acetylcarnitine, glycine, glycerophosphocholine, 1,2-dioleoyl-sn-glycero-3-phosphocholine, d-aspartic acid, oleic acid, and l-glutamate were significantly decreased, whereas creatinine and thymine were significantly increased. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that 50 metabolic pathways were enriched in the M/C group and T/M group rat serum, of which 12 metabolic pathways were significantly different, mainly distributed in lipid metabolism, amino acid, and endocrine system metabolic pathways. Fermented milk ameliorated inflammation, oxygenation, and hepatocyte injury by regulating lipid metabolism, amino acid metabolic pathways, and related metabolites in the serum of rats with nonalcoholic fatty liver disease.

Averrhoa carambola leaves prevent dyslipidemia and oxidative stress in a rat model of poloxamer-407-induced acute hyperlipidemia

Background: The star fruit [Averrhoa carambola L (Oxalidaceae)] is traditionally used in the treatment of many ailments in many countries. It possesses several pharmacological activities, including antioxidant and anti-inflammatory effects. However, it contains the neurotoxic caramboxin and its high content of oxalic acid limits its consumption by individuals with compromised kidney function. This study assessed the anti-hyperlipidemic and antioxidant activities of different fractions of the methanolic extract of A. carambola leaves (MEACL). Methods: The antioxidant activity was investigated using FRAP, and ABTS and DPPH radical-scavenging assays and the inhibitory activity toward pancreatic lipase (PL) and HMG-CoA reductase was assayed in vitro. Acute hyperlipidemia was induced by poloxamer-407 (P-407) in rats and different fractions of MEACL (n-hexane, chloroform, n-butanol, ethyl acetate (EA), water, and chloroform) were orally administered. Cholesterol and triglycerides were determined at 0, 12, 24, and 48 h and LDL-C, vLDL-C, HDL-C, lipid peroxidation (LPO) and antioxidants were assayed after 48 h. The expression of ABCA1, ABCG5, ABCG8, LDL-R, SREBP-1, and SREBP-2 and the activity of HMG-CoA reductase were assayed in the liver of P-407-administered rats treated with the EA fraction. Results: The in vitro data revealed potent radical-scavenging activities of MEACL fractions with the most potent effect showed by the EA fraction that also suppressed the activities of HMG-CoA reductase and PL. In P-407-induced hyperlipidemic rats, all fractions prevented dyslipidemia as shown by the decrease in total cholesterol, triglycerides, LDL-C, vLDL-C and atherogenic index. MEACL and its fractions prevented LPO and boosted GSH, superoxide dismutase, glutathione peroxidase, and catalase in P-407-administered rats. The EA fraction showed more effective anti-hyperlipidemic and antioxidant effects than other fractions and downregulated SREBP-2 while upregulated ABCA1 and LDL-R and ameliorated LPL and HMG-CoA reductase in hyperlipidemic rats. Conclusion: MEACL showed in vitro and in vivo antioxidant activity and the EA fraction significantly ameliorated dyslipidemia in a rat model of P-407-induced acute hyperlipidemia by modulating LPL, PL, HMG-CoA reductase, and cholesterolgenesis-related factors. Therefore, the leaves of A. carambola represent a safe alternative for the star fruit particularly in kidney disease patients, and the EA is the most effective anti-hyperlipidemic and antioxidant fraction.

Overall metabolic network analysis of urine in hyperlipidemic rats treated with Bidens bipinnata L

Hyperlipidemia has been highlighted as one of the most prominent and global chronic conditions nowadays. Bidens bipinnata L. (BBL), a folk medicine in contemporary China, has efficacy in the treatment of hyperlipidemia (HLP) in China. Although some physiological and pathological function parameters of hyperlipidemia have been investigated, little information about the changes in small metabolites in biofluids has been reported. In the present study, global metabolic profiling with high-performance liquid chromatography-linear ion trap/Orbitrap high-resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) combined with a pattern recognition method was performed to discover the underlying lipid-regulating mechanisms of BBL on hyperlipidemic rats induced by high-fat diet (HFD). The total of four metabolites, up- or down-regulated (p < 0.05 or 0.01), were identified and contributed to the progression of hyperlipidemia. These promising identified biomarkers underpin the metabolic pathway, including glyoxylate and dicarboxylate metabolism, the TCA cycle, sphingolipid metabolism and purine metabolism. They are disturbed in hyperlipidemic rats, and are identified using pathway analysis with MetPA. The altered metabolite indices could be regulated closer to normal levels after BBL intervention. The results demonstrated that urinary metabolomics is a powerful tool in the clinical diagnosis and treatment of hyperlipidemia to provide information on changes in metabolite pathways.

Caenorhabditis elegans deep lipidome profiling by using integrative mass spectrometry acquisitions reveals significantly altered lipid networks

Lipidomics coverage improvement is essential for functional lipid and pathway construction. A powerful approach to discovering organism lipidome is to combine various data acquisitions, such as full scan mass spectrometry (full MS), data-dependent acquisition (DDA), and data-independent acquisition (DIA). Caenorhabditis elegans (C. elegans) is a useful model for discovering toxic-induced metabolism, high-throughput drug screening, and a variety of human disease pathways. To determine the lipidome of C. elegans and investigate lipid disruption from the molecular level to the system biology level, we used integrative data acquisition. The methyl-tert-butyl ether method was used to extract L4 stage C. elegans after exposure to triclosan (TCS), perfluorooctanoic acid, and nanopolystyrene (nPS). Full MS, DDA, and DIA integrations were performed to comprehensively profile the C. elegans lipidome by Q-Exactive Plus MS. All annotated lipids were then analyzed using lipid ontology and pathway analysis. We annotated up to 940 lipids from 20 lipid classes involved in various functions and pathways. The biological investigations revealed that when C. elegans were exposed to nPS, lipid droplets were disrupted, whereas plasma membrane-functionalized lipids were likely to be changed in the TCS treatment group. The nPS treatment caused a significant disruption in lipid storage. Triacylglycerol, glycerophospholipid, and ether class lipids were those primarily hindered by toxicants. Finally, toxicant exposure frequently involved numerous lipid-related pathways, including the phosphoinositide 3-kinase/protein kinase B pathway. In conclusion, an integrative data acquisition strategy was used to characterize the C. elegans lipidome, providing valuable biological insights into hypothesis generation and validation.

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Multiple data acquisitions were used to profile the lipidome of C. elegans.

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940 detected lipids of 20 main classes involved in various pathways.

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Relevant hypotheses were generated using high-coverable lipidomics and pathways analysis.

Mass Spectrometry-Based Metabolomic and Lipidomic Analysis of the Effect of High Fat/High Sugar Diet and GreenshellTM Mussel Feeding on Plasma of Ovariectomized Rats

This study aimed to examine the changes in lipid and metabolite profiles of ovariectomized (OVX) rats with diet-induced metabolic syndrome-associated osteoarthritis (MetOA) after supplementation with greenshell mussel (GSM) using an untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics approach. Ninety-six rats were fed with one of four diets: control, control supplemented with GSM + GSM, high fat/high sugar (HFHS), or high fat/high sugar enriched with GSM (HFHS + GSM). After 8 weeks on experimental diets, half of the rats in each group underwent OVX and the other half were sham operated. After being fed for an additional 28 weeks, blood samples were collected for the metabolomics analysis. Lipid and polar metabolites were extracted from plasma and analysed by LC-MS. We identified 29 lipid species from four lipid subclasses (phosphatidylcholine, lysophosphatidylcholine, diacylglycerol, and triacylglycerol) and a set of eight metabolites involved in amino acid metabolism (serine, threonine, lysine, valine, histidine, pipecolic acid, 3-methylcytidine, and cholic acid) as potential biomarkers for the effect of HFHS diet and GSM supplementation. GSM incorporation more specifically in the control diet generated significant alterations in the levels of several lipids and metabolites. Further studies are required to validate these findings that identify potential biomarkers to follow OA progression and to monitor the impact of GSM supplementation.

Restriction of Dietary Advanced Glycation End Products Induces a Differential Plasma Metabolome and Lipidome Profile

SCOPE

Diets with low content in advanced glycation end products (AGEs) lead to beneficial properties in highly prevalent age-related diseases. To shed light on the mechanisms behind, the changes induced by a low AGE dietary intervention in the circulating metabolome are analyzed.

METHODS AND RESULTS

To this end, 20 non-diabetic patients undergoing peritoneal dialysis are randomized to continue their usual diet or to one with a low content of AGEs for 1 month. Then, plasmatic metabolome and lipidomes are analyzed by liquid-chromatography coupled to mass spectrometry. The levels of defined AGE structures are also quantified by ELISA and by mass-spectrometry. The results show that the low AGE diet impinged significant changes in circulating metabolomes (166 molecules) and lipidomes (91 lipids). Metabolic targets of low-AGE intake include sphingolipid, ether-lipids, and glycerophospholipid metabolism. Further, it reproduces some of the plasma characteristics of healthy aging.

CONCLUSION

The finding of common pathways induced by low-AGE diets with previous metabolic traits implicated in aging, insulin resistance, and obesity suggest the usefulness of the chosen approach and supports the potential extension of this study to other populations.

Metabolomic analysis of untargeted bovine uterine secretions in dairy cows with endometritis using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Endometritis is among the most common bovine uterine diseases; as a cause of infertility, it affects the progress of the cattle industry. In this study, we used a novel technique based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry for comparative metabolomics of uterine secretions in healthy cows and cows with endometritis, classified based on clinical symptoms. Univariate and multivariate statistical analyses revealed significant differences between the two groups (n = 12). Compared with healthy uterine secretion samples, in the clinical endometritis samples, coumaric acid, benzoic acid, and equol were downregulated. However, l-phenylalanine, glutamine, succinic acid, linoleate, arachidonic acid, and other metabolites were upregulated, revealing variations between healthy cows and cows with endometritis (p < 0.05). This metabolomic approach may provide an in-depth understanding of endometritis pathobiology, along with a theoretical framework for the diagnosis and treatment of this bovine disease.

Changes of Lipopolysaccharide-Induced Acute Kidney and Liver Injuries in Rats Based on Metabolomics Analysis

Background

The bacterial endotoxin lipopolysaccharide (LPS) was the classic inducer to establish many inflammatory disease models, especially multiple organ injury. Evidences indicated that the mechanism that causes inflammation response is not just related to cytokine release. The main aim of this study was to better elucidate the possible links between metabolic changes and the pathogenesis of LPS-induced acute liver and kidney in order to understand the mechanisms and screening therapeutic targets for developing early diagnostic strategies and treatments.

Methods

An experimental rat model was established by intraperitoneal injection of 10 mg/kg LPS. An untargeted metabolomics analysis of the serum in the LPS and control groups was carried out using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/QTOF-MS). LPS-induced pathological damage in the lungs, liver, kidneys, and colon was observed, along with changes in biochemical indexes, indicating that there was a severe inflammatory response in many organs after administration of LPS for 8 h. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) showed distinct separation in the serum metabolite profiles between the LPS and control groups, indicating significant changes in endogenous metabolites.

Results

The untargeted metabolomics analysis showed that there were 127 significantly different serum metabolites and 53 altered pathways after LPS administration, including pathways related to the metabolism of D-glutamine and D-glutamate, taurine and hypotaurine, beta-alanine, glutathione, and butanoate, which are involved in the inflammatory response, oxidative stress, and amino acid metabolism.

Conclusion

The study suggested that LPS-induced acute liver and kidney injury mainly involves inflammatory response, oxidative stress, and protein synthesis, finally causing multi-organ damage. Correcting the disturbances to the metabolites and metabolic pathways may help to prevent and/or treat LPS-induced acute liver and kidney damage.

An exploratory approach for an oriented development of an untargeted hydrophilic interaction liquid chromatography-mass spectrometry platform for polar metabolites in biological matrices

The analysis of polar metabolites based on liquid chromatography-mass spectrometry (LC-MS) methods should take into consideration the complexity of interactions in LC columns to be able to cover a broad range of metabolites of key biological pathways. Therefore, in this study, different chromatographic columns were tested for polar metabolites including reversed-phase and hydrophilic interaction liquid chromatography (HILIC) columns. Based on a column screening, two new generations of zwitterionic HILIC columns were selected for further evaluation. A tree-based method optimization was applied to investigate the chromatographic factors affecting the retention mechanisms of polar metabolites with zwitterionic stationary phases. The results were evaluated based on a scoring system which was applied for more than 80 polar metabolites with a high coverage of key human metabolic pathways. The final optimized methods showed high complementarity to analyze a wide range of metabolic classes including amino acids, small peptides, sugars, amino sugars, phosphorylated sugars, organic acids, nucleobases, nucleosides, nucleotides and acylcarnitines. Optimized methods were applied to analyze different biological matrices, including human urine, plasma and liver cell extracts using an untargeted approach. The number of high-quality features (< 30% median relative standard deviation) ranged from 3,755 for urine to 5,402 for the intracellular metabolome of liver cells, showing the potential of the methods for untargeted purposes.

UPLC/Q-TOF-MS/MS-based metabolomics revealed the lipid-lowering effect of Ilicis Rotundae Cortex on high-fat diet induced hyperlipidemia rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ilicis Rotundae Cortex (IRC), a Chinese crude drug, has been widely utilized in Guangdong and Guangxi provinces of China to treat or prevent cardiovascular diseases.

AIM OF STUDY

This investigation aims to study the lipid-lowering effect of IRC, as well as the regulating effect on the endogenous metabolites in hyperlipidemia rats.

MATERIALS AND METHODS

High-fat diet induced hyperlipidemia rats were administrated with different doses of IRC extract (0.5, 1.0 and 2.0 g/kg/day) for 5 weeks. Simvastatin was used as the positive control. Body weight, serum lipid levels and histopathology of liver were evaluated. The metabolic profiles of plasma, urine and cecum content were analyzed using UPLC/Q-TOF-MS/MS-based metabolomics approach coupled with multivariate data analysis.

RESULTS

The levels of serum TC, TG, LDL-C, AST and ALT were significantly decreased and HDL-C level was increased in IRC treatment groups. The hepatic histomorphology was partially restored. 23, 26 and 15 metabolites in plasma, urine and cecum content were determined as the biological biomarkers, respectively. IRC extract could partially recover the disturbed metabolic pathways of bile acid metabolism, linoleic acid metabolism, arachidonic acid metabolism, taurine and hypotaurine metabolism, glyoxylate and dicarboxylate metabolism, glycerophospholipid metabolism, synthesis and degradation of ketone bodies, sphingolipid metabolism and riboflavin metabolism.

CONCLUSION

This study demonstrated that IRC could effectively improve the serum lipids and partially restore the hepatic histomorphology. The underlying metabolic mechanism mainly included improving the metabolism of bile acids, glycerophospholipid, sphingolipid, fatty acid and amino acid. This is the first study on the lipid-lowering effect of IRC from the perspective of metabolomics.

Effect of fish paste products "Hanpen" intake in Sprague-Dawley rats

Fish paste product, "Hanpen," is a traditional type of Japanese food made from minced fish as well as imitation crab and kamaboko, and a marshmallow-like soft texture is characteristic of hanpen. Hanpen is known as a high-protein and low-fat food. However, there is a lack of evidence on its health benefits. The aim of this study was to investigate the effects of hanpen intake on organ weight and biomarker levels in Sprague-Dawley rats with diets consisting of hanpen for 84 days as an initial study. Male, 6-week-old Sprague-Dawley rats were divided into two groups: group I, fed normal diets, and group II, fed normal diets with 5% dried hanpen. Throughout the 84-day treatment period, we checked body weight and food intake, and after 84 days, we performed organ weight and blood biochemical analyses. No significant differences were seen in body weight, food intake, organ weight, and most biochemical parameters between group I and group II. Interestingly, total cholesterol (T-CHO) and high-density lipoprotein cholesterol (HDL-C) levels of group II were significantly higher than those of group I after administration for 84 days. Moreover, lactate dehydrogenase (LDH) level of group II was marked lower than that of group I, and other liver function parameters of group II tended to be lower than those of group I. As conclusion, "Hanpen," a Japanese traditional food, could be effective as a functional food for human health management worldwide.

GC-MS-based metabolomics research on the anti-hyperlipidaemic activity of Prunella vulgaris L. polysaccharides

Prunella vulgaris polysaccharides (PVPs) have a variety of biological activities, but the mechanism and extent of their anti-hyperlipidaemic effect remain unclear. In vitro, PVPs had a significant inhibitory effect on angiotensin (Ang II)-induced vascular smooth muscle cell (VSMC) proliferation. A metabolomics approach based on gas chromatography-mass spectrometry (GC-MS) and chemometrics was established in this study to evaluate the anti-hyperlipidaemic activity of PVPs in a high-fat Sprague-Dawley rat model. In vivo, PVPs could significantly reduce the weight gain and the increases in serum total cholesterol (TC), low-density lipoprotein (LDL)-C and non-high-density lipoprotein (HDL)-C levels observed in rats fed a high-fat diet; they could also significantly increase serum GSH-Px activity, reduce the content of MDA and TNF-α and decrease abdominal fat volume in rats. Furthermore, PVPs exerted a repairing effect on morphological and structural damage in liver tissue cells in hyperlipidaemic rats fed a high-fat diet. PVPs improved lipid metabolism disorder in rats. Alanine, threonine, succinic acid, proline, inositol and arachidonic acid levels in the serum were considered potential biomarkers involved in amino acid, glucose, energy and lipid metabolism. Therefore, PVPs may interfere with hyperlipidaemia through anti-lipid peroxidation effects, attenuation of inflammation and regulation of glucose, amino acid, energy and lipid metabolism.

Optimization of extraction parameters of Pleurotus eryngii polysaccharides and evaluation of the hypolipidemic effect

The hot water extraction of polysaccharides from the fruiting body of Pleurotus eryngii was studied. In this paper, according to single-factor experiments, a response surface methodology and the Box–Behnken design were applied to optimize the extraction parameters of Pleurotus eryngii polysaccharides (PEP). The optimal extraction conditions were as follows: a temperature of 79 °C, a time of 3.11 h, a ratio of water to fruiting bodies of 52.6 mL g⁻¹. Under these parameters, the yield of PEP was 7.53%. When mice with hyperlipidemia were administered low, medium or high doses of PEP, their body weight was reduced compared with the model group, and the degree of weight loss was proportional to the dose. At the 16th week of PEP treatment, blood lipid biochemical parameters such as total cholesterol, triglycerides, low-density lipoprotein-cholesterol, aspartate aminotransferase, and alanine aminotransferase levels were all decreased. However, high-density lipoprotein-cholesterol levels increased after PEP treatment. Histopathological examination of the liver showed that low, medium and high doses of PEP had a certain liver protective effect. High-dose PEP treatment had the best effect in regard to lipid-lowering and liver protection. In addition, the metabolome of the mice was analyzed by LC-MS, and the results indicated that C16 sphinganine can be used as a potential biomarker, which displayed significant differences among the six groups. In conclusion, the possible metabolic mechanism of the PEP on lipid-lowering was closely related to sphingolipid metabolism.

The hot water extraction of polysaccharides from the fruiting body of Pleurotus eryngii was studied.

Serum and urine metabolomics reveal potential biomarkers of T2DM patients with nephropathy

BACKGROUND

Diabetes is a metabolic disease and is often accompanied by severe microvascular and macrovascular complications. A comprehensive understanding of its complex mechanisms can help prevent type 2 diabetes mellitus (T2DM) complications, such as diabetic nephropathy (DN).

METHODS

To reveal the systemic metabolic changes related to renal injury, clinical information of T2DM patients with or without nephropathy was collected, and it was found that serum urea levels of DN patients were significantly higher in T2DM patients without nephropathy. Further along the disease progression, the serum urea levels also gradually increased. We used gas chromatograph coupled with time-of-flight mass spectrometry (GC-TOFMS) metabolomics to analyze the serum and urine metabolites of T2DM patients with or without nephropathy to study the metabolic changes associated with the disease.

RESULTS

Finally, we identified 61 serum metabolites and 46 urine metabolites as potential biomarkers related to DN (P<0.05, VIP >1). In order to determine which metabolic pathways were major altered in DN, we summarized pathway analysis based on P values from their impact values and enrichment. There were 9 serum metabolic pathways and 12 urine metabolic pathways with significant differences in serum and urine metabolism, respectively.

CONCLUSIONS

This study emphasizes that GC-TOFMS-based metabolomics provides insight into the potential pathways in the pathogenesis and progression of DN.

Metabolomic profiling of liver tissues after acute administration of vardenafil in rats

Erectile dysfunction (ED) diseases have almost affected 100 million men all over the world. Orally administered phosphodiesterase 5 (PDE 5) inhibitors are the most used pharmaceutical formulations for the treatment of ED. In this study, it is aimed to investigate the metabolomics feature of orally administered vardenafil in rats. To carry out the experimental procedure eight male Wistar albino rats were used. Their livers were gently removed and metabolomics profiles of each sample were determined by UPLC Q-TOF MS. Identification of metabolites was achieved by the METLIN database. Cluster analysis was also performed via Principle Component Analysis. Several metabolites were identified and results were evaluated by XCMS software. UPLC Q-TOF MS could be successfully applied to profile biomarkers and help us understand the molecular mechanisms of vardenafil usage. It was concluded that the level of some metabolites, responsible for the collagen synthesis and Kreb's cycle, has been statistically significant after the vardenafil administration.

Antihyperlipidemic and Antioxidant Effects of Averrhoa Carambola Extract in High-Fat Diet-Fed Rats

The present study explored the antihyperlipidemic potential of a standardized methanolic extract of Averrhoa carambola (A. carambola) leaf (MEACL) in high-fat diet (HFD)-fed rats. The standardized MEACL was orally administered at different doses (250, 500, and 1000 mg/kg) to HFD-induced hyperlipidemic rats for five weeks. Serum lipid profile, body weight changes, body mass index (BMI), daily food intake, relative organ weight, and histology of the liver were evaluated. In addition, the effect of MEACL on HMG-CoA reductase and pancreatic lipase activities as well as hepatic and fecal lipids was demonstrated. MEACL supplementation reduced serum lipids in HFD-fed rats in a dose-dependent manner. Histopathological scores revealed that 1000 mg/kg MEACL restored the damage to liver tissue in hyperlipidemic rats. MEACL decreased the body mass index (BMI), atherogenic index, and hepatic cholesterol and triglycerides and increased fecal cholesterol and bile acids in HFD-fed rats. Also, MEACL ameliorated lipid peroxidation and improved antioxidant defenses in the liver of HFD-fed rats. Furthermore, HMG-CoA reductase and lipase were suppressed by MEACL. In conclusion, this study shows the potential effect of MEACL to ameliorate hyperlipidemia and oxidative stress in HFD-fed rats. It prevented hepatic lipid accumulation and exerted an inhibitory effect on HMG-CoA reductase and lipase.

Effect of ginsenoside Rh2 on renal apoptosis in cisplatin-induced nephrotoxicity in vivo

BACKGROUND

Ginsenoside Rh₂ (Rh₂), an important ingredient from Panax ginseng, has received much attention due to a range of pharmacological actions.

PURPOSE

The aim of the study was to investigate the therapeutic potential Rh₂ on cisplatin (CDDP)-induced nephrotoxicity and to elucidate involved mechanisms.

STUDY DESIGN

An in vivo mice model of CDDP-induced nephrotoxicity was established by a single intraperitoneal injection of CDDP (20 mg/kg) to assess the effects of Rh₂ on renal biochemical parameter, oxidative stress, inflammation tubular cell apoptosis and serum metabolic profiles.

RESULTS

Rh₂ protected against CDDP-induced renal dysfunction and ameliorated CDDP-induced oxidative stress, histopathological damage, inflammation and tubular cell apoptosis in kidney. Rh₂ treatment had significantly increased expression of Bcl-2 and decreased expression of p53, Bax, cytochrome c, caspase-8, caspase-9, and caspase-3 in kidney tissues. Metabolomic analysis identified 29 altered serum metabolites in Rh₂ treatment mice.

CONCLUSION

These results suggest that Rh₂ protects against CDDP-induced nephrotoxicity via action on caspase-mediated pathway.

Scutellariae Radix and Coptidis Rhizoma Improve Glucose and Lipid Metabolism in T2DM Rats via Regulation of the Metabolic Profiling and MAPK/PI3K/Akt Signaling Pathway

Aim Scutellariae Radix (SR) and Coptidis Rhizoma (CR) have often been combined to cure type 2 diabetes mellitus (T2DM) in the clinical practice for over thousands of years, but their compatibility mechanism is not clear. Mitogen-activated protein kinase (MAPK) signaling pathway has been suggested to play a critical role during the process of inflammation, insulin resistance, and T2DM. This study was designed to investigate their compatibility effects on T2DM rats and explore the underlying mechanisms by analyzing the metabolic profiling and MAPK/PI3K/Akt signaling pathway. Methods The compatibility effects of SR and CR were evaluated with T2DM rats induced by a high-fat diet (HFD) along with a low dose of streptozocin (STZ). Ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was performed to discover potential biomarkers. The levels of pro-inflammatory cytokines; biochemical indexes in serum, and the activities of key enzymes related to glycometabolism in liver were assessed by ELISA kits. qPCR was applied to examine mRNA levels of key targets in MAPK and insulin signaling pathways. Protein expressions of p65; p-p65; phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K); phosphorylated-PI3K (p-PI3K); protein kinase B (Akt); phosphorylated Akt (p-Akt) and glucose transporter 2 (Glut2) in liver were investigated by Western blot analysis. Results Remarkably, hyperglycaemia, dyslipidemia, inflammation, and insulin resistance in T2DM were ameliorated after oral administration of SR and CR, particularly their combined extracts. The effects of SR, CR, low dose of combined extracts (LSC) and high dose of combined extracts (HSC) on pro-inflammatory cytokine transcription in T2DM rats showed that the MAPK pathway might account for the phenomenon with down-regulation of MAPK (P38 mitogen-activated protein kinases (P38), extracellular regulated protein kinases (ERK), and c-Jun N-terminal kinase (JNK)) mRNA, and protein reduction in p-P65. While mRNA levels of key targets such as insulin receptor substrate 1 (IRS1), PI3K, Akt2, and Glut2 in the insulin signaling pathway were notably up-modulated, phosphorylations of PI3K, Akt, and expression of Glut2 were markedly enhanced. Moreover, the increased activities of phosphoenolpyruvate carboxykinase (PEPCK), fructose-1,6-bisphosphatase (FBPase), glucose 6-phosphatase (G6Pase), and glycogen phosphorylase (GP) were highly reduced and the decreased activities of glucokinase (GK), phosphofructokinase (PFK), pyruvate kinase (PK), and glycogen synthase (GS) in liver were notably increased after treatment. Further investigation indicated that the metabolic profiles of plasma and urine were clearly improved in T2DM rats. Fourteen potential biomarkers (nine in plasma and five in urine) were identified. After intervention, these biomarkers returned to normal level to some extent. Conclusion The results showed that SR, CR, and combined extract groups were normalized. The effects of combined extracts were more remarkable than single herb treatment. Additionally, this study also showed that the metabonomics method is a promising tool to unravel how traditional Chinese medicines work.

Arabinoxylan Attenuates Type 2 Diabetes by Improvement of Carbohydrate, Lipid, and Amino Acid Metabolism

SCOPE

Type 2 diabetes is a complex metabolic and endocrine disorder worldwide, which causes severe health and economic problems. The aim of this study is to investigate the molecular mechanisms by which arabinoxylan from Plantago asiatica L. attenuates type 2 diabetes from the perspective of urine metabolomics.

METHODS AND RESULTS

High-fat diet and streptozotocin-induced type 2 diabetic rats are treated with arabinoxylan, then the urine samples are collected for untargeted metabolomics analysis by UPLC-Triple-TOF/MS. Diabetes causes significant increases in the levels of acetone, glucose, 2-oxoglutarate, and leucine, and significant decreases in the concentrations of creatine, histidine, lysine, l-tryptophan, hippurate, l-cysteine, kynurenine, and arabitol as compared with normal rats (p < 0.01). And these 12 metabolites (with VIP cut-off value > 1) can be used as biomarkers in type 2 diabetes. A total of 21 urinary metabolites are significantly improved by arabinoxylan administration in diabetic rats, and these metabolites are mainly involved in TCA cycle, and metabolism of lipid and ketone body, taurine and hypotaurine, tryptophan, and branched chain amino acids.

CONCLUSION

Arabinoxylan administration improves carbohydrate, lipid, and amino acid metabolism in type 2 diabetic rats, which provide important insights into the mechanisms underlying type 2 diabetes as well as the effects of arabinoxylan.

Sanhuang Xiexin Tang Ameliorates Type 2 Diabetic Rats via Modulation of the Metabolic Profiles and NF-κB/PI-3K/Akt Signaling Pathways

Sanhuang Xiexin Tang (SXT), a classic prescription, has been clinically used to cure diabetes for thousands of years, but its mechanism remains unclear. Here, a systematic in-depth research was performed to unravel how it worked by the signaling pathway and metabonomics analysis. Our studies were conducted using high-fat diets (HFD) and streptozocin (STZ)-induced type 2 diabetes mellitus (T2DM) rats. The blood glucose was measured by a glucose-meter. Protein contents were determined by western blotting or ELISA and mRNA expression was identified by RT-PCR analysis. The pathological status of pancreas was assessed by histopathological analysis. Furthermore, Ultra Performance Liquid Chromatography-Quadrupole-Time of Flight/Mass Spectrometry (UPLC-Q-TOF/MS) coupled with multivariate statistical analysis was performed to discover potential biomarkers and the associated pathways. Hyperglycaemia, insulin resistance, dyslipidemia and inflammation in T2DM rats were significantly ameliorated after 7-week oral administration of SXT. The expressions of phosphatidylinositol-3-kinase (PI-3K), protein kinase B (Akt), glucose transporters-4 (GLUT4) Mrna, and p-PI-3K, p-Akt, GLUT4 protein involved in the PI-3K/Akt signaling pathway of T2DM were markedly up-regulated. Further investigation indicated that the perturbance of metabolic profiling in T2DM rats was obviously reversed by SXT and 38 potential biomarkers were screened and identified. Our study might help clarify the mechanism of SXT and provide some evidences for its clinical application in the future.

PPARα Mediates the Hepatoprotective Effects of Nutmeg

Nutmeg is a Traditional Chinese Medicine used to treat gastrointestinal diseases. Some reports have indicated that nutmeg has hepatoprotective activity. In this study, a thioacetamide (TAA)-induced acute liver injury model in mice was used to explore the mechanism of the protective effects of nutmeg extract (NME), including its major bioactive component myrislignan. The results indicated that NME could effectively protect TAA-induced liver damage as assessed by recovery of increased serumtransaminases, decrease in hepatic oxidative stress, and lower hepatic inflammation. Metabolomics analysis further revealed that treatment with NME led to the recovery of a series of lipids including lysophosphatidylcholines that were decreased and a lowering of acylcarnitines that were increased in mouse plasma and liver after TAA exposure. Gene expression analysis demonstrated that the hepatoprotective effect of NME was achieved by modulation of the peroxisome proliferator-activated receptor alpha (PPARα) as well as the decrease in oxidative stress. NME could not protect from TAA-induced liver injury in Ppara-null mice, suggesting that its protective effect was dependent on PPARα. Myrislignan, a representative neolignan in nutmeg, showed potent protective activity against TAA-induced liver toxicity. These data demonstrate that nutmeg alleviates TAA-induced liver injury through the modulation of PPARα and that the lignan compounds in nutmeg such as myrislignan partly contributed to this action.

Effects of honey fromMimosa quadrivalvisL. (malícia) produced by theMelipona subnitidaD. (jandaíra) stingless bee on dyslipidaemic rats

The supplementation with malícia honey alters the lipid metabolism, antioxidant status and intestinal health parameters of rats with diet-induced dyslipidaemia.

Untargeted Metabolomics Provides Insight into the Mechanisms Underlying Resistant Hypertension

BACKGROUND

Resistant hypertension (RH) affects about 15-20% of treated hypertensive patients worldwide. RH increases the risk of cardiovascular events such as myocardial infarction and stroke by 50%. The pathological mechanisms underlying resistance to treatment are still poorly understood.

OBJECTIVE

The main goal of this pilot study was to determine and compare plasma metabolomic profiles in resistant and non-resistant hypertensive patients.

METHODS

We applied untargeted metabolomic profiling in plasma samples collected from 69 subjects with RH and 81 subjects with controlled hypertension. To confirm patients' compliance to antihypertensive treatment, levels of selected drugs and their metabolites were determined in plasma samples with the LC-ESI-TOF/MS technique.

RESULTS

The results showed no statistically significant differences in the administration of antihypertensive drug in the compared groups. We identified 19 up-regulated and 13 downregulated metabolites in the RH.

CONCLUSION

The metabolites altered in RH are linked to oxidative stress and inflammation, endothelium dysfunction, vasoconstriction and cell proliferation. Our results may generate new hypothesis about RH development and progression.

UPLC-Q-TOF/MS-based metabonomic studies on the intervention effects of aspirin eugenol ester in atherosclerosis hamsters

Based on the pro-drug principle, aspirin and eugenol were used to synthesize aspirin eugenol ester (AEE) by esterification reaction. In present study, the anti-atherosclerosis effects of AEE were investigated in hamsters with the utilization of metabonomic approach based on UPLC-Q-TOF/MS. Biochemical parameters and histopathological injures in stomach, liver and aorta were evaluated. In atherosclerotic hamster, oral administration of AEE normalized biochemical profile such as reducing TG, TCH and LDL, and significantly reduced body weight gain, alleviated hepatic steatosis and improved pathological lesions in aorta. Slight damages in stomach mucous were found in AEE group. Plasma and urine samples in control, model and AEE groups were scattered in the partial least squares-discriminate analysis (PLS-DA) score plots. Thirteen endogenous metabolites in plasma such as lysophosphatidylcholine (LysoPC), leucine and valine, and seventeen endogenous metabolites in urine such as citric acid, phenol sulphate and phenylacetylglycine were selected as potential biomarkers associated with atherosclerosis. They were considered to be in response to anti-atherosclerosis effects of AEE, mainly involved in glycerophospholipid metabolism, amino acid metabolism and energy metabolism. This study extended the understanding of endogenous alterations of atherosclerosis and offered insights into the pharmacodynamic activity of AEE.

Urine and serum metabolite profiling of rats fed a high-fat diet and the anti-obesity effects of caffeine consumption

In this study, we investigated the clinical changes induced by a high fat diet (HFD) and caffeine consumption in a rat model. The mean body weight of the HFD with caffeine (HFDC)-fed rat was decreased compared to that of the HFD-fed rat without caffeine. The levels of cholesterol, triglycerides (TGs), and free fatty acid, as well as the size of adipose tissue altered by HFD, were improved by caffeine consumption. To investigate the metabolites that affected the change of the clinical factors, the urine and serum of rats fed a normal diet (ND), HFD, and HFDC were analyzed using ultra performance liquid chromatography quadruple time-of-flight mass spectrometry (UPLC-Q-TOF-MS), gas chromatography (GC-TOF-MS), and linear trap quadruple mass spectrometry (LTQ-XL-MS) combined with multivariate analysis. A total of 68 and 52 metabolites were found to be different in urine and serum, respectively. After being fed caffeine, some glucuronide-conjugated compounds, lysoPCs, CEs, DGs, TGs, taurine, and hippuric acid were altered compared to the HFD group. In this study, caffeine might potentially inhibit HFD-induced obesity and we suggest possible biomarker candidates using MS-based metabolite profiling.

Metabolomics for laboratory diagnostics

Metabolomics is an emerging approach in a systems biology field. Due to continuous development in advanced analytical techniques and in bioinformatics, metabolomics has been extensively applied as a novel, holistic diagnostic tool in clinical and biomedical studies. Metabolome's measurement, as a chemical reflection of a current phenotype of a particular biological system, is nowadays frequently implemented to understand pathophysiological processes involved in disease progression as well as to search for new diagnostic or prognostic biomarkers of various organism's disorders. In this review, we discussed the research strategies and analytical platforms commonly applied in the metabolomics studies. The applications of the metabolomics in laboratory diagnostics in the last 5 years were also reviewed according to the type of biological sample used in the metabolome's analysis. We also discussed some limitations and further improvements which should be considered taking in mind potential applications of metabolomic research and practice.