Plasma Lipidomics Reveals Insights into Anti-Obesity Effect of Chrysanthemum morifolium Ramat Leaves and Its Constituent Luteolin in High-Fat Diet-Induced Dyslipidemic Mice

Plant and algal lipidomes: Analysis, composition, and their societal significance

Plants and algae play a crucial role in the earth's ecosystems. Through photosynthesis they convert light energy into chemical energy, capture CO2 and produce oxygen and energy-rich organic compounds. Photosynthetic organisms are primary producers and synthesize the essential omega 3 and omega 6 fatty acids. They have also unique and highly diverse complex lipids, such as glycolipids, phospholipids, triglycerides, sphingolipids and phytosterols, with nutritional and health benefits. Plant and algal lipids are useful in food, feed, nutraceutical, cosmeceutical and pharmaceutical industries but also for green chemistry and bioenergy. The analysis of plant and algal lipidomes represents a significant challenge due to the intricate and diverse nature of their composition, as well as their plasticity under changing environmental conditions. Optimization of analytical tools is crucial for an in-depth exploration of the lipidome of plants and algae. This review highlights how lipidomics analytical tools can be used to establish a complete mapping of plant and algal lipidomes. Acquiring this knowledge will pave the way for the use of plants and algae as sources of tailored lipids for both industrial and environmental applications. This aligns with the main challenges for society, upholding the natural resources of our planet and respecting their limits.

Luteolin: A promising multifunctional natural flavonoid for human diseases

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/β-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

Flavonoids, gut microbiota, and host lipid metabolism

Flavonoids are widely distributed in nature and have a variety of beneficial biological effects, including antioxidant, anti-inflammatory, and anti-obesity effects. All of these are related to gut microbiota, and flavonoids also serve as a bridge between the host and gut microbiota. Flavonoids are commonly used to modify the composition of the gut microbiota by promoting or inhibiting specific microbial species within the gut, as well as modifying their metabolites. In turn, the gut microbiota extensively metabolizes flavonoids. Hence, this reciprocal relationship between flavonoids and the gut microbiota may play a crucial role in maintaining the balance and functionality of the metabolism system. In this review, we mainly highlighted the biological effects of antioxidant, anti-inflammatory and antiobesity, and discussed the interaction between flavonoids, gut microbiota and lipid metabolism, and elaborated the potential mechanisms on host lipid metabolism.

Luteolin Mitigates Diabetic Dyslipidemia in Rats by Modulating ACAT-2, PPARα, SREBP-2 Proteins, and Oxidative Stress

Diabetic dyslipidemia is a crucial link between type-2 diabetes mellitus (T2DM) and atherosclerotic cardiovascular diseases (ASCVD). Natural biologically active substances have been advocated as complementary remedies for ASCVD and T2DM. Luteolin, a flavonoid, exhibits antioxidant, hypolipidemic, and antiatherogenic effects. Hence, we aimed to determine influence of luteolin on lipid homeostasis and hepatic damage in rats with T2DM induced by high-fat-diet (HFD) and streptozotocin (STZ). After being fed HFD for 10 days, male Wistar rats received 40 mg/kg STZ intraperitoneal injection on 11th day. Seventy-two hours later, hyperglycemic rats (fasting glucose > 200 mg/dL) were randomized into groups, and oral hydroxy-propyl-cellulose, atorvastatin (5 mg/kg), or luteolin (50 mg/kg or 100 mg/kg) administered daily, while continuing HFD for 28 days. Luteolin significantly ameliorated dyslipidemia levels and concomitantly improved atherogenic index of plasma in a dose-dependent manner. Increased levels of malondialdehyde and diminished levels of superoxide dismutase, catalase, and glutathione in HFD-STZ-diabetic rats were significantly regulated by luteolin. Luteolin significantly intensified PPARα expression while decreasing expression of acyl-coenzyme A:cholesterol acyltransferase-2 (ACAT-2) and sterol regulatory element binding protein-2 (SREBP-2) proteins. Moreover, luteolin effectively alleviated hepatic impairment in HFD-STZ-diabetic rats to near-normal control levels. The findings of the present study expound mechanisms by which luteolin mitigated diabetic dyslipidemia and alleviated hepatic impairment in HFD-STZ-diabetic rats by amelioration of oxidative stress, modulation of PPARα expression, and downregulation of ACAT-2 and SREBP-2. In conclusion, our results imply that luteolin may be efficacious in management of dyslipidemia in T2DM, and future research may be essential to substantiate our findings.

Therapeutic Mechanism of Baicalin in Experimental Colitis Analyzed Using Network Pharmacology and Metabolomics

Background

Baicalin is an important active flavonoid isolated from the roots of Scutellaria baicalensis (S. baicalensis), a well-known traditional Chinese herb used in treating inflammatory bowel disease (IBD). The objectives of this study were to assess the potential benefit of baicalin in experimental colitis, as well as to investigate metabolic biomarkers of experimental colitis in conjunction with network pharmacology.

Methods

Using a widely utilized network pharmacology technique, baicalin's targets and pathways were predicted. Simultaneously, experimental colitis was induced by intrarectal administration of TNBS. Histopathology examinations were performed to confirm pathological changes. Plasma samples were examined by using an untargeted metabolomics technique based on ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) to screen differential metabolites and associated metabolic pathways. Additionally, network pharmacology and integrated analysis of metabolomics were used to identify the primary targets.

Results

Through network pharmacology research, tumor necrosis factor (TNF), interleukin 6 (IL6), serine/threonine-protein kinase (AKT1), and other 7 proteins were found to be the main targets of baicalin against IBD. The untargeted metabolomics results showed that 47 metabolites in glycerophospholipids and sphingolipid metabolism were involved as key pathways in the experimental colitis model group. 19 metabolites, including Sphingomyelin (SM d42:2, SM d42:1, SM d34:1), Lysophosphatidic acids (LPA 18:4), 1-Palmitoylglycerophosphocholine, and 17(18)-EpETE were demonstrated as key metabolites for baicalin to exert effects. Moreover, udp-glucose ceramide glucosyltransferase (UGCG), sphingomyelin synthase 1 (SGMS1), and sphingosine kinase (SPHK1) were predicted as sphingolipids-linked targets of baicalin against experimental colitis by integrative analysis.

Conclusion

Based on these results, it implies that sphingolipid metabolism and sphingolipid signaling pathway might be acted as therapeutic mechanism for baicalin against experimental colitis.

Gut microbiota in a mouse model of obesity and peripheral neuropathy associated with plasma and nerve lipidomics and nerve transcriptomics

BACKGROUND

Peripheral neuropathy (PN) is a common complication in obesity, prediabetes, and type 2 diabetes, though its pathogenesis remains incompletely understood. In a murine high-fat diet (HFD) obesity model of PN, dietary reversal (HFD-R) to a low-fat standard diet (SD) restores nerve function and the nerve lipidome to normal. As the gut microbiome represents a potential link between dietary fat intake and nerve health, the current study assessed shifts in microbiome community structure by 16S rRNA profiling during the paradigm of dietary reversal (HFD-R) in various gut niches. Dietary fat content (HFD versus SD) was also correlated to gut flora and metabolic and PN phenotypes. Finally, PN-associated microbial taxa that correlated with the plasma and sciatic nerve lipidome and nerve transcriptome were used to identify lipid species and genes intimately related to PN phenotypes.

RESULTS

Microbiome structure was altered in HFD relative to SD but rapidly reversed with HFD-R. Specific taxa variants correlating positively with metabolic health associated inversely with PN, while specific taxa negatively linked to metabolic health positively associated with PN. In HFD, PN-associated taxa variants, including Lactobacillus, Lachnoclostridium, and Anaerotruncus, also positively correlated with several lipid species, especially elevated plasma sphingomyelins and sciatic nerve triglycerides. Negative correlations were additionally present with other taxa variants. Moreover, relationships that emerged between specific PN-associated taxa variants and the sciatic nerve transcriptome were related to inflammation, lipid metabolism, and antioxidant defense pathways, which are all established in PN pathogenesis.

CONCLUSIONS

The current results indicate that microbiome structure is altered with HFD, and that certain taxa variants correlate with metabolic health and PN. Apparent links between PN-associated taxa and certain lipid species and nerve transcriptome-related pathways additionally provide insight into new targets for microbiota and the associated underlying mechanisms of action in PN. Thus, these findings strengthen the possibility of a gut-microbiome-peripheral nervous system signature in PN and support continuing studies focused on defining the connection between the gut microbiome and nerve health to inform mechanistic insight and therapeutic opportunities. Video Abstract.

Metabolomics Provides Insights into Renoprotective Effects of Semaglutide in Obese Mice

PURPOSE

Semaglutide, a new long-acting glucagon-like peptide-1 analogue, has shown benefits for renal diseases, but its direct role on kidney metabolism under obesity remains unclear. The study aims to elucidate the protective effect and metabolic modulation mechanism of semaglutide on obesity-related kidney injury.

METHODS

Male C57BL/6J mice were divided into control and obesity groups. Mice in the obesity group had a high-fat diet and were treated with or without semaglutide (30nmol/kg/day). The study assayed blood biochemistry and then evaluated renal pathological injury through Periodic Acid-Schiff staining and electron microscopy. Metabolomics was utilized to analyze obesity-related metabolites in kidney samples.

RESULTS

Semaglutide significantly improved glucose homeostasis, insulin resistance, and kidney injury in obese mice. We successfully identified 377 altered metabolites (P<0.05). It was suggested that semaglutide directly improved oxidative stress and inflammation-related metabolites such as nicotinamide adenine dinucleotide (NAD+) and adenosine in the kidney of obese mice, which have not been documented in obesity-related kidney injury. Relevant enriched pathways were included phospholipids and lysophospholipids metabolism, purine metabolism, NAD+ metabolism, and insulin resistance-related metabolism. They could serve as potential targets for intervention of obesity-related kidney injury.

CONCLUSION

Our study revealed the metabolomics-based renoprotective mechanism of semaglutide in obese mice for the first time. The innovation lied in the identified metabolites such as NAD+ and adenosine targeted by semaglutide, which have not been documented in obesity-related kidney injury. Semaglutide may be a promising therapy for obesity-related kidney diseases.

Huangshan Maofeng Green Tea Extracts Prevent Obesity-Associated Metabolic Disorders by Maintaining Homeostasis of Gut Microbiota and Hepatic Lipid Classes in Leptin Receptor Knockout Rats

Huangshan Maofeng green tea (HMGT) is one of the most well-known green teas consumed for a thousand years in China. Research has demonstrated that consumption of green tea effectively improves metabolic disorders. However, the underlying mechanisms of obesity prevention are still not well understood. This study investigated the preventive effect and mechanism of long-term intervention of Huangshan Maofeng green tea water extract (HTE) on obesity-associated metabolic disorders in leptin receptor knockout (Lepr^−/−) rats by using gut microbiota and hepatic lipidomics data. The Lepr^−/− rats were administered with 700 mg/kg HTE for 24 weeks. Our results showed that HTE supplementation remarkably reduced excessive fat accumulation, as well as ameliorated hyperlipidemia and hepatic steatosis in Lepr^−/− rats. In addition, HTE increased gut microbiota diversity and restored the relative abundance of the microbiota responsible for producing short chain fatty acids, including Ruminococcaceae, Faecalibaculum, Veillonellaceae, etc. Hepatic lipidomics analysis found that HTE significantly recovered glycerolipid and glycerophospholipid classes in the liver of Lepr^−/− rats. Furthermore, nineteen lipid species, mainly from phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), and triglycerides (TGs), were significantly restored increases, while nine lipid species from TGs and diglycerides (DGs) were remarkably recovered decreases by HTE in the liver of Lepr^−/− rats. Our results indicated that prevention of obesity complication by HTE may be possible through maintaining homeostasis of gut microbiota and certain hepatic lipid classes.

Effects of Modified Sang ju-Yin Decoction Combined with IFNαlb Nebulization on IL-1β and HBD2 in Children with Asthmatic Bronchitis

Background

Breathing disease swelling of the lung tubes caused by viral infection is more and more likely to develop into related to the lung tubes breathing disease, especially repeating breathing loudly.

Objective

To investigate the effect of modified Sang ju-Yin Decoction combined with Interferon (IFN)αlb nebulization on children with asthmatic bronchitis and the effects of IL-1β and β-defensin 2 (HBD2).

Materials and Methods

The clinical data of 80 children with asthmatic bronchitis who were diagnosed and treated in our hospital from May 2019 to May 2021 were selected as the research objects and divided into the control group and the observation group with 40 cases in each group according to different treatment methods. Among them, the control group was nebulized with IFNαlb, and the observation group was given addition and subtraction of Sang ju-Yin Decoction based on the control group. The clinical symptoms, pulmonary function indexes, adverse reactions, and effects on serum inflammatory indexes were observed and compared between the two groups.

Results

There was no significant difference in the scores of symptoms and signs between the two groups before treatment (P > 0.05), while the scores of shortness of breath, cough, stridor, lung rales, and signs after treatment of observation group were better than those of the control group (P < 0.05). There was no significant difference in serum inflammatory indexes and pulmonary function indexes between the two groups before treatment (P > 0.05), while the differences in IL-6, IL-10, TNF-α, IL-1β, and HBD2 after treatment were significant between the two groups (P < 0.05). After treatment, the RR, TV, and PEF indexes of the two groups of children were significantly improved (P < 0.05). After treatment, the adverse reaction rate of liver function damage, dry throat discomfort, rash, nausea, and vomiting in the observation group was 7.5%, which was significantly lower than 27.5% in the control group (P < 0.05).

Conclusion

Modified Sang ju-Yin Decoction combined with IFNαlb nebulization can improve symptoms and promote the recovery of patients in the treatment of acute bronchitis.

Lipidomics Reveals That Rice or Flour as a Single Source of Carbohydrates Cause Adverse Health Effects in Rats

The type of diet is very important for the maintenance of health and nutrition. How the sole source of carbohydrates from rice- or flour-based diet affect blood sugar has not been elucidated for a long time. In order to explore the effects of these diets, sixty SD rats were randomly divided into three groups: control group (C group, AIN-93, standard diet), rice diet group (R group), and flour diet group (F group). All the rats were fed for 7 weeks in total by the assigned diets for 4 weeks (stage 1, S1) and all by the AIN-93 diet for 3 weeks (stage 2, S2). The body weights of all the rats were monitored and serum samples were taken for testing blood glucose, biochemical indicators and untargeted lipidome. It was found that both rice and flour-based diets caused weight gain, but the flour diet had a significant increase in blood sugar and low-density lipoprotein (LDL), while a significant decrease in albumin (ALB) and triglycerides (TG). Twenty-three and 148 lipids were changed by lipidomics in the rice diet group and flour diet group, respectively, and two lipids showed the same changes in the two groups, all belonging to TGs, namely TG (16:0/16:0/16:1) and TG (16:0/16:1/18:2), which showed that a single diet source had a significant effect on the health of rats. Fortunately, we can recover this effect through the subsequent standard diet, allowing the rats to return to normal blood sugar, weight and biochemical indicators. A model can predict the diet types through the logistic regression method. Finally, we proposed that a single diet increased blood sugar and weight through a decrease in TGs, and blood sugar and weight returned to normal after a standard diet. Taken together, the short-term negative effects caused by a single diet can be recovered by a standard diet and further proves the importance of diet types.

Serum metabolite profiling yields insights into health promoting effect of A. muciniphila in human volunteers with a metabolic syndrome

Reduction of A. muciniphila relative abundance in the gut microbiota is a widely accepted signature associated with obesity-related metabolic disorders. Using untargeted metabolomics profiling of fasting plasma, our study aimed at identifying metabolic signatures associated with beneficial properties of alive and pasteurized A. muciniphila when administrated to a cohort of insulin-resistant individuals with metabolic syndrome. Our data highlighted either shared or specific alterations in the metabolome according to the form of A. muciniphila administered with respect to a control group. Common responses encompassed modulation of amino acid metabolism, characterized by reduced levels of arginine and alanine, alongside several intermediates of tyrosine, phenylalanine, tryptophan, and glutathione metabolism. The global increase in levels of acylcarnitines together with specific modulation of acetoacetate also suggested induction of ketogenesis through enhanced β-oxidation. Moreover, our data pinpointed some metabolites of interest considering their emergence as substantial compounds pertaining to health and diseases in the more recent literature.

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.

Hypolipidemic Effects and Preliminary Mechanism of Chrysanthemum Flavonoids, Its Main Components Luteolin and Luteoloside in Hyperlipidemia Rats

This study aimed to investigate the key constituents and preliminary mechanism for the hypolipidemic activity of chrysanthemum flavonoids. Hyperlipidemia (HPL) rats were divided into five groups: the model control group (MC); Chrysanthemum flavone intervention group (CF); luteolin intervention group; luteoloside intervention group and simvastatin intervention group. The body weight, organ coefficient, serum lipids, antioxidant activity, and lipid metabolism enzymes were detected. Hematoxylin and eosin (H&E) staining was used to observe the liver and adipose tissue. Chrysanthemum flavonoids, luteolin, and luteoloside can reduce the weight and levels of total cholesterol (TC), triglycerides (TG), and LDL-C, and increase the level of HDL-C in the blood and reduce liver steatosis. Indicators of liver function (AST, ALT, and ALP) improved. The antioxidant activity (GSH-Px, CAT, SOD) and enzymes associated with lipid catabolism (FAβO, CYP7A1, and HL) increased, while lipid peroxidation products (MDA) and enzymes associated with lipid synthesis (FAS, HMG-CoA, and DGAT) decreased. Chrysanthemum flavonoids had a better effect on the antioxidant level and lipid metabolism-related enzyme activity. There was no significant difference in the effects of the chrysanthemum flavonoids, luteolin, and Luteoloside on improving blood lipids and hepatic steatosis—mechanisms that may be related to antioxidant levels and regulating enzymes involved in the metabolism of fatty acids, cholesterol, and triglycerides in the liver. However, chrysanthemum flavonoids had a stronger antioxidant and lipid metabolism regulation ability, and the long-term effects may be better.

Diets, Foods and Food Components' Effect on Dyslipidemia

Hypercholesterolemia is a well-known independent risk factor for cardiovascular disease and a recognized target of pharmacological therapeutic agents in both primary and secondary prevention [...].

Dietary Luteolin: A Narrative Review Focusing on Its Pharmacokinetic Properties and Effects on Glycolipid Metabolism

Luteolin, a flavone subclass of flavonoids, is commonly found in food plants and has multiple biological activities. Recently, evidence is growing with regard to the potential of luteolin intake to beneficially affect glycolipid metabolism disorders (GLMDs), particularly insulin resistance, diabetes, and obesity. The aim of this contribution is to provide an overview of recent advances in identifying and understanding the pharmacokinetic properties (absorption, metabolism, and bioavailability) of luteolin, its regulatory effects on glycolipid metabolism, and the underlying mechanisms of action of luteolin in the brain, liver, adipose tissues, and other tissues/organs. Collectively, luteolin or its principal metabolites may contribute to counteracting GLMDs, especially for human obesity and diabetes.