Lipid metabolism disorders and lipid mediator changes of mice in response to long-term exposure to high-fat and high sucrose diets and ameliorative effects of mulberry leaves.

Mulberry leaves exhibit anti-lipogenic and lipid-lowering effects. However, the lipid biomarkers and underlying mechanisms for the improvement of the action of mulberry leaves on obesity and lipid metabolism disorders have not been sufficiently investigated yet. Herein, biochemical analysis combined with metabolomics targeting serum lipid mediators (oxylipins) were used to explore the efficacy and underlying mechanisms of mulberry leaf water extract (MLWE) in high-fat and high-sucrose diet (HFHSD)-fed mice. Our results showed that MLWE supplementation not only decreased body weight gain, serum total triglycerides, low-density lipoprotein cholesterol, alanine transaminase and aspartate transaminase levels, but also increased the serum level of high-density lipoprotein cholesterol. In addition, MLWE supplementation also ameliorated hepatic steatosis and lipid accumulation. These beneficial effects were associated with down-regulating genes involved in oxidative stress, inflammation, and lipogenesis such as acetyl-CoA carboxylase and fatty acid synthase, and up-regulating genes related to lipolysis that encoded peroxisome proliferator-activated receptor α, adiponectin (ADPN), adiponectin receptor (AdipoR) 1, AdipoR2, adenosine monophosphate-activated protein kinase (AMPK) and hormone-sensitive lipase. Moreover, a total of 54 serum lipid mediators were differentially changed in HFHSD-fed mice, among which 11 lipid mediators from n-3 polyunsaturated fatty acids (PUFAs) were apparently reversed by MLWE. These findings indicated that the ADPN/AMPK pathway, anti-inflammation, anti-oxidation, and n-3 PUFA metabolism played important roles in anti-obesity and improvement of lipid metabolism disorders modulated by MLWE supplementation.

Amelioration of lipid accumulations and metabolism disorders in differentiation and development of 3T3-L1 adipocytes through mulberry leaf water extract.

BACKGROUND: Obesity is a worldwide problem that resulted from the excessive fat accumulation in adipose tissue, leading to the impairment of individual health. Mulberry leaf is an important traditional Chinese medicine and has been used to alleviate obesity for a long term. However, its underlying molecular mechanisms have not been fully elucidated yet. PURPOSE: In this study, we aimed to investigate the inhibition effects of mulberry leaf water extract (MLWE) on lipid accumulation during the process of differentiation of 3T3-L1 preadipocytes and development of mature adipocytes through the combination of molecular biology assays and metabolomic analysis. METHODS: The quality consistency and main chemical ingredients of MLWE were analyzed by high performance liquid chromatography and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), respectively. Oil red O staining was used to mirror lipid accumulation. Lipogenesis-, lipolysis- and inflammation-related genes were evaluated by real-time PCR and western blot, respectively. Untargeted metabolomics were performed by LC-MS/MS. RESULTS: Prepared method and quality of MLWE were stable and reliable. A total of 34 compounds were identified and 14 of them were undoubtedly confirmed. MLWE supplementation could dose-dependently inhibit the aggregation of lipid droplets, and the expressions of sterol regulatory element-binding protein (SREBP)-1c, peroxisome proliferator-activated receptor (PPAR) γ, acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), tumor necrosis factor (TNF)-α and interleukin (IL)-6, and increase the expressions of adenosine monophosphate-activated protein kinase (AMPK), hormone-sensitive lipase (HSL) and IL-10 in the differentiation of preadipocytes. Furthermore, MLWE treatment could dose-dependently decrease the level of triglycerides and the expressions of ACC, FAS, TNF-α, and IL-6, and up-regulate the level of glycerol and the expressions of PPARα, adiponectin (ADPN), adiponectin receptor (AdipoR) 1, AdipoR2, AMPK, HSL, and IL-10 in the development of mature adipocytes. Untargeted metabolomics showed that a total of 5 and 18 differential metabolites were reversed by MLWE intervention in the differentiation of preadipocytes and the development of mature adipocytes, respectively, which involved in the biosynthesis of unsaturated fatty acids, arachidonic acid metabolism and glycerophospholipids metabolism. CONCLUSION: Taken together, this study firstly verified that MLWE could effectively alleviate lipid accumulation and inflammation by regulating ADPN/AMPK-mediated signaling pathways and relevant metabolic disturbances including biosynthesis of unsaturated fatty acids, arachidonic acid metabolism and glycerophospholipids metabolism.

MS-based metabolite analysis of two licorice chalcones in mice plasma, bile, feces, and urine after oral administration.

Isoliquiritigenin (ILG) and isoliquiritin (ILQ), two kinds of major flavonoids in licorice, are biological active substances with antioxidant, anti-inflammatory, and tumor-suppressive effects. However, their in vivo metabolites, possible material basis of this two licorice chalcones for the treatment of diseases, have not been studied completely. To determine the metabolism of ILG and ILQ, after oral administration of 100 mg/kg/day of these compounds for consecutive 8 days, the metabolites of these two licorice chalcones in mice plasma, urine, feces, and bile were determined using liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry in this study. The structures of those metabolites were tentatively identified according to their fragment pathways, accurate masses, characteristic product ions, metabolism law, and reference standards-matching. As a result, a total of 25 and 29 metabolites of ILG and ILQ were identified, respectively. Seven main metabolic pathways, oxidation and reduction, deglycosylation and glycosylation, dehydroxylation and hydroxylation, demethoxylation and methoxylation, acetylation, glucuronidation, and sulfation, were summarized to tentatively explain how the metabolites were biologically transformed. These results provide the important information on the metabolism of ILG and ILQ, which may be helpful for the further research of their pharmacological mechanism.

Metabolic profiling of mice plasma, bile, urine and feces after oral administration of two licorice flavonones.

ETHNOPHARMACOLOGICAL RELEVANCE: Licorice is an ancient food and medicinal plant. Liquiritigenin and liquiritin, two kinds of major flavonoes in licorice, are effective substances used as antioxidant, anti-inflammatory and tumor-suppressive food, cosmetics or medicines. However, their in vivo metabolites have not been fully explored. AIM OF STUDY: To clarify the metabolism of liquiritigenin and liquiritin in mice. MATERIALS AND METHODS: In this study, we developed a liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry approach to determine the metabolites in mice plasma, bile, urine and feces after oral administration of liquiritigenin or liquiritin. The structures of those metabolites were tentatively identified according to their fragment pathways, accurate masses, characteristic product ions, metabolism laws or reference standard matching. RESULTS: A total of 26 and 24 metabolites of liquiritigenin or liquiritin were respectively identified. The products related with apigenin, luteolin or quercetin were the major metabolites of liquiritigenin or liquiritin in mice. Seven main metabolic pathways including (de)hydrogenation, (de)hydroxylation, (de)glycosylation, (de)methoxylation, acetylation, glucuronidation and sulfation were summarized to tentatively explain their biotransformation. CONCLUSION: This study not only can provide the evidence for in vivo metabolites and pharmacokinetic mechanism of liquiritigenin and liquiritin, but also may lay the foundation for further development and utilization of liquiritigenin, liquiritin and then licorice.

Metabolomics Study of Metabolic Changes in Renal Cells in Response to High-Glucose Exposure Based on Liquid or Gas Chromatography Coupled With Mass Spectrometry.

Diabetic nephropathy (DN) is one of the most serious microvascular complications and the leading causes of death in diabetes mellitus (DM). To find biomarkers for prognosing the occurrence and development of DN has significant clinical value for its prevention, diagnosis, and treatment. In this study, a non-targeted cell metabolomics-based ultra-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry and gas chromatography coupled with mass spectrometry was developed and performed the dynamic metabolic profiles of rat renal cells including renal tubular epithelial cells (NRK-52E) and glomerular mesangial cells (HBZY-1) in response to high glucose at time points of 12 h, 24 h, 36 h, and 48 h. Some potential biomarkers were then verified using clinical plasma samples collected from 55 healthy volunteers, 103 DM patients, and 57 DN patients. Statistical methods, such as principal component analysis and partial least squares to latent structure-discriminant analysis were recruited for data analyses. As a result, palmitic acid and linoleic acid (all-cis-9,12) were the potential indicators for the occurrence and development of DN, and valine, leucine, and isoleucine could be used as the prospective biomarkers for DM. In addition, rise and fall of leucine and isoleucine levels in plasma could be used for prognosing DN in DM patients. Through this study, we established a novel non-targeted cell dynamic metabolomics platform and identified potential biomarkers that may be applied for the diagnosis and prognosis of DM and DN.

Off-line two-dimensional liquid chromatography coupled with diode array detection and quadrupole-time of flight mass spectrometry for the biotransformation kinetics of Ginkgo biloba leaves extract by diabetic rat liver microsomes.

Ginkgo biloba leaves extract (GBE), one of the most widely used traditional Chinese medicines worldwide, can be used for the treatment of diabetes mellitus (DM). However, its biotransformation in liver is not fully known under the state of DM. In this study, an off-line hydrophilic interaction × reversed-phase two-dimensional liquid chromatography (HILIC × RP 2D-LC) system coupled with diode array detection (DAD) and quadrupole time-of-flight mass spectrometry (q/TOF-MS) was established for the qualification and quantification of the biotransformation of GBE in normal and diabetic rat liver microsomes (RLMs). 6 metabolites were tentatively identified according to the exact molecular weights and the characteristic fragment ions provided by q/TOF-MS data. The results of metabolic stability showed that the metabolic ratio of four target compounds including quercetin, genistein, kaempferol and isorhamnetin in diabetic RLMs were significantly enhanced when comparing with normal RLMs. The results of enzyme kinetics showed that compared with normal RLMs, the Michaelis-Menten constant (Km) value of genistein was obvious increased while its maximal velocity (Vmax) and intrinsic clearance (CLint) values were significantly decreased by diabetic RLMs, and the Vmax and CLint values of kaempferol and isorhamnetin were notably enhanced while their Km values were markedly reduced. For the half-time (t1/2) values of four target compounds and the Km, Vmax and CLint values of quercetin, there were not statistically significant changes between normal and diabetic RLMs. The results suggest that the developed off-line 2D LC-DAD-q/TOF-MS method is an easy and accurate approach for the study of GBE biotransformation in RLMs and may provide the essential data for further pharmacological and clinical studies of GBE.