Therapeutic effect of quercetin on renal function and tissue damage in the obesity induced rats

Altitudinal variation of dragon fruit metabolite profiles as revealed by UPLC-MS/MS-based widely targeted metabolomics analysis

BACKGROUND

Geographical factors affect the nutritional, therapeutic and commercial values of fruits. Dragon fruit (Hylocereus spp) is a popular fruit in Asia and a potential functional food with diverse pharmacological attributes. Although it is produced in various localities, the information related to the altitudinal variation of dragon fruit nutrients and active compounds is scarce. Hence, this study aimed to investigate the variations in metabolite profiles of H. polyrhizus (variety Jindu1) fruit pulps from three different altitudes of China, including Wangmo (WM, 650 m), Luodian (LD, 420 m), and Zhenning (ZN, 356 m). Jindu1 is the main cultivated pitaya variety in Guizhou province, China.

RESULTS

The LC-MS (liquid chromatography-mass spectroscopy)-based widely targeted metabolic profiling identified 645 metabolites, of which flavonoids (22.64%), lipids (13.80%), phenolic acids (12.40%), amino acids and derivatives (10.39%), alkaloids (8.84%), and organic acids (8.37%) were dominant. Multivariate analyses unveiled that the metabolite profiles of the fruit differed regarding the altitude. Fruits from WM (highest altitude) were prime in quality, with higher levels of flavonoids, alkaloids, nucleotides and derivatives, amino acids and derivatives, and vitamins. Fruits from LD and ZN had the highest relative content of phenolic acids and terpenoids, respectively. We identified 69 significantly differentially accumulated metabolites across the pulps of the fruits from the three locations. KEGG analysis revealed that flavone and flavonol biosynthesis and isoflavonoid biosynthesis were the most differentially regulated. It was noteworthy that most active flavonoid compounds exhibited an increasing accumulation pattern along with the increase in altitude. Vitexin and isovitexin were the major differentially accumulated flavonoids. Furthermore, we identified two potential metabolic biomarkers (vitexin and kaempferol 3-O-[2-O-β-D-galactose-6-O-a-L-rhamnose]-β-D-glucoside) to discriminate between dragon fruits from different geographical origins.

CONCLUSION

Our findings provide insights into metabolic changes in dragon fruits grown at different altitudes. Furthermore, they show that growing pitaya at high altitudes can produce fruit with higher levels of bioactive compounds, particularly flavonoids.

Hepatoprotective activity of Lactéol® forte and quercetin dihydrate against thioacetamide-induced hepatic cirrhosis in male albino rats

Liver cirrhosis is a silent disease in humans and is experimentally induced by many drugs and toxins as thioacetamide (TAA) in particular, which is the typical model for experimental induction of hepatic fibrosis. Thus, the objective of the present study was to elucidate the possible protective effects of lactéol® forte (LF) and quercetin dihydrate (QD) against TAA-induced hepatic damage in male albino rats. Induction of hepatotoxicity was performed by TAA injection (200 mg/kg I/P, twice/ week) in rats. LF (1 × 109 CFU/rat 5 times/week) and QD (50 mg/kg 5 times/week) treated groups were administered concurrently with TAA injection (200 mg/kg I/P, twice/ week). The experimental treatments were conducted for 12 weeks. Hepatotoxicity was evaluated biochemically by measuring alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) in the serum and histopathologically with the scoring of histopathological changes besides histochemical assessment of collagen by Masson's trichrome and immunohistochemical analysis for α-smooth muscle actin (α-SMA), Ki67 and caspase-3 expression in liver sections. Our results indicated that LF and QD attenuated some biochemical changes and histochemical markers in TAA-mediated hepatotoxicity in rats by amelioration of biochemical markers and collagen, α-SMA, Ki67 and caspase3 Immunoexpression. Additionally, LF and QD supplementation downregulated the proliferative, necrotic, fibroblastic changes, eosinophilic intranuclear inclusions, hyaline globules and Mallory-like bodies that were detected histopathologically in the TAA group. In conclusion, LF showed better hepatic protection than QD against TAA-induced hepatotoxicity in rats by inhibiting inflammatory reactions with the improvement of some serum hepatic transaminases, histopathological picture and immunohistochemical markers.

Limosilactobacillus fermentum Strains as Novel Probiotic Candidates to Promote Host Health Benefits and Development of Biotherapeutics: A Comprehensive Review

Fruits and their processing by-products are sources of potentially probiotic strains. Limosilactobacillus (L.) fermentum strains isolated from fruit processing by-products have shown probiotic-related properties. This review presents and discusses the results of the available studies that evaluated the probiotic properties of L. fermentum in promoting host health benefits, their application by the food industry, and the development of biotherapeutics. The results showed that administration of L. fermentum for 4 to 8 weeks promoted host health benefits in rats, including the modulation of gut microbiota, improvement of metabolic parameters, and antihypertensive, antioxidant, and anti-inflammatory effects. The results also showed the relevance of L. fermentum strains for application in the food industry and for the formulation of novel biotherapeutics, especially nutraceuticals. This review provides evidence that L. fermentum strains isolated from fruit processing by-products have great potential for promoting host health and indicate the need for a translational approach to confirm their effects in humans using randomized, double-blind, placebo-controlled trials.

Rutin and Hesperidin Revoke the Hepatotoxicity Induced by Paclitaxel in Male Wistar Rats via Their Antioxidant, Anti-Inflammatory, and Antiapoptotic Activities

Paclitaxel, one of the most effective chemotherapeutic drugs, is used to treat various cancers but it is exceedingly toxic when used long-term and can harm the liver. This study aimed to see if rutin, hesperidin, and their combination could protect male Wistar rats against paclitaxel (Taxol)-induced hepatotoxicity. Adult male Wistar rats were subdivided into 5 groups (each of six rats). The normal group was orally given the equivalent volume of vehicles for 6 weeks. The paclitaxel-administered control group received intraperitoneal injection of paclitaxel at a dose of 2 mg/Kg body weight twice a week for 6 weeks. Treated paclitaxel-administered groups were given paclitaxel similar to the paclitaxel-administered control group together with oral supplementation of rutin, hesperidin, and their combination at a dose of 10 mg/Kg body weight every other day for 6 weeks. The treatment of paclitaxel-administered rats with rutin and hesperidin significantly reduced paclitaxel-induced increases in serum alanine transaminase, aspartate transaminase, lactate dehydrogenase, alkaline phosphatase, and gamma-glutamyl transferase activities as well as total bilirubin level and liver lipid peroxidation. However, the levels of serum albumin, liver glutathione content, and the activities of liver superoxide dismutase and glutathione peroxidase increased. Furthermore, paclitaxel-induced harmful hepatic histological changes (central vein and portal area blood vessel congestion, fatty changes, and moderate necrotic changes with focal nuclear pyknosis, focal mononuclear infiltration, and Kupffer cell proliferation) were remarkably enhanced by rutin and hesperidin treatments. Moreover, the elevated hepatic proapoptotic mediator (caspase-3) and pro-inflammatory cytokine (tumor necrosis factor-α) expressions were decreased by the three treatments in paclitaxel-administered rats. The cotreatment with rutin and hesperidin was the most effective in restoring the majority of liver function and histological integrity. Therefore, rutin, hesperidin, and their combination may exert hepatic protective effects in paclitaxel-administered rats by improving antioxidant defenses and inhibiting inflammation and apoptosis.

The protective effects of hesperidin and curcumin on 5-fluorouracil-induced nephrotoxicity in mice

Nephrotoxicity is a very important complication of 5-fluorouracil (5-FU)-treated cancer patients. Increased oxidative stress, kidney damage, and apoptosis play an important role in the pathogenesis of nephrotoxicity caused by 5-FU. In this study, protective effects of two natural compounds, hesperidin and curcumin, on experimentally induced kidney damage in mice with 5-FU were determined. Application of 5-FU resulted in severe histopathological changes and severe renal failure with increased serum urea and creatinine levels. Also, 5-FU-induced kidney damage, increased levels of malondialdehyde (MDA), decreased superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) activity, and glutathione (GSH) level have been demonstrated. Also, where 5-FU is in the concentration of caspase-3 and 8-OHdG immune-positive cells and therefore causes apoptosis and DNA damage in kidney tissue cells. However, especially high doses of hesperidin and curcumin treatment significantly improved 5-FU-induced oxidative stress/lipid peroxidation, apoptosis/DNA damage, and renal dysfunction. Based on these data, our results suggest that hesperidin and curcumin may be used as new and promising agents against 5-FU-induced nephrotoxicity.

Comparative metabolomics analysis of different sesame (Sesamum indicum L.) tissues reveals a tissue-specific accumulation of metabolites

BACKGROUND

Sesame (Sesamum indicum L.) leaves, flowers, especially seeds are used in traditional medicine to prevent or cure various diseases. Its seed's market is expanding. However, the other tissues are still underexploited due to the lack of information related to metabolites distribution and variability in the plant. Herein, the metabolite profiles of five sesame tissues (leaves, fresh seeds, white and purple flowers, and fresh carpels) have been investigated using ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS)-based widely targeted metabolomics analysis platform.

RESULTS

In total, 776 metabolites belonging to diverse classes were qualitatively and quantitatively identified. The different tissues exhibited obvious differences in metabolites composition. The majority of flavonoids predominantly accumulated in flowers. Amino acids and derivatives, and lipids were identified predominantly in fresh seeds followed by flowers. Many metabolites, including quinones, coumarins, tannins, vitamins, terpenoids and some bioactive phenolic acids (acteoside, isoacteoside, verbascoside, plantamajoside, etc.) accumulated mostly in leaves. Lignans were principally detected in seeds. 238 key significantly differential metabolites were filtered out. KEGG annotation and enrichment analyses of the differential metabolites revealed that flavonoid biosynthesis, amino acids biosynthesis, and phenylpropanoid biosynthesis were the main differently regulated pathways. In addition to the tissue-specific accumulation of metabolites, we noticed a cooperative relationship between leaves, fresh carpels, and developing seeds in terms of metabolites transfer. Delphinidin-3-O-(6"-O-p-coumaroyl)glucoside and most of the flavonols were up-regulated in the purple flowers indicating they might be responsible for the purple coloration.

CONCLUSION

This study revealed that the metabolic processes in the sesame tissues are differently regulated. It offers valuable resources for investigating gene-metabolites interactions in sesame tissues and examining metabolic transports during seed development in sesame. Furthermore, our findings provide crucial knowledge that will facilitate sesame biomass valorization.

Dose-Related Urinary Metabolic Alterations of a Combination of Quercetin and Resveratrol-Treated High-Fat Diet Fed Rats

Most herbal polyphenols and flavonoids reveals multiple ameliorative benefits for obesity caused by chronic metabolic disorders. Accumulated studies have revealed that preferable therapeutic effects can be obtained through clinical combination of these two kinds of natural compounds for obesity improvement. The typical representative research was the combination of quercetin and resveratrol (CQR), in which the ratio of quercetin and resveratrol is 2:1, demonstrating a synergistic effect in anti-obesity process. Although there exists reports clarifying the mechanism of the combination of two to improve obesity from the perspective of improving adipose tissue inflammation or modulating the composition of intestinal flora, there are few further studies on the mechanism of drug action from the perspective of metabolites transformation. In this research, we mainly focused on the alterations of endogenous metabolites in rats, and analyzed the urine metabolites of obese and intervention model. Therefore, a gas chromatography-mass spectrometry (GC-MS) based metabolomics approach was applied to assess the potential effects and mechanisms of CQR at different dosages (45, 90, and 180 mg/kg) in high fat diet (HFD)-induced obesity rats. Body weight gain and visceral fat weight were reduced by CQR, as well as blood lipid and inflammatory factor levels were increased by CQR in a dose-related manner. Urinary metabolomics revealed 22 differential metabolites related to the HFD-induced obesity, which were reversed in a dose-dependent manner by CQR, of which 8 were reversed in the 45 mg/kg CQR group, 15 were reversed in the 90 mg/kg CQR group, and 18 were reversed in the 180 mg/kg CQR group. Combined with bioinformatics and pattern recognition, the results demonstrated that the key differential metabolites were basically involved in amino acid metabolism, galactose metabolism, pantothenate and CoA biosynthesis, pyruvate metabolism and lysine degradation. In summary, our results showed significant therapeutic action by CQR administration and remarkable metabolomic changes after HFD feeding and CQR intervention. Urinary metabolomic analysis was highlighted on account of providing holistic and comprehensive insights into the pathophysiological mechanisms of the HFD-induced obesity, which also supplied clues for the future mechanism studies of CQR's anti-obesity effects.

The Effects of Selenium in Acrylamide-Induced Nephrotoxicity in Rats: Roles of Oxidative Stress, Inflammation, Apoptosis, and DNA Damage

We sought to determine the effects of selenium (Se) on acrylamide (ACR)-induced nephrotoxicity in rats. In our study, 50 adult male Sprague-Dawley rats weighing 200-250 g were randomly divided into five groups. The control group was given intra-gastric (i.g.) saline (1 mL) for 10 days. The ACR group was given i.g. ACR in saline (38.27 mg/kg titrated to 1 mL) for 10 days. The Se0.5 + ACR and Se1 + ACR groups were administered Se in saline (0.5 and 1 mg/kg, respectively) for 10 days and given i.g. ACR (38.27 mg/kg) one hour after the Se injections. The Se1 group was administered i.g. Se (1 mg/kg) for 10 days. On day 11, intracardiac blood samples were obtained from the rats while they were under anesthesia, after which they were euthanized by decapitation. Urea and creatinine concentrations of blood serum samples were analyzed with an autoanalyzer. Enzyme-linked immunosorbence immunosorbent assay (ELISA) was used to quantify malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), tumor necrosis factor-α (TNF-α), nuclear factor-κB (NF-κB), interleukin (IL)-33, IL-6, IL-1β, cyclooxygenase-2 (COX-2), kidney injury molecule-1 (KIM-1), mitogen-activated protein kinase-1 (MAPK-1), and caspase-3 in kidney tissues. Renal tissues were evaluated by histopathological and immunohistochemical examinations for 8-hydroxylo-2'-deoxyguanosin 8-hydroxy-2'-deoxyguanosine (8-OhDG) and Bax. Serum urea and creatinine levels were higher in the ACR group than in the control, and these ACR-induced increases were prevented by high doses of Se. Additionally, ACR induced the renal oxidative stress, inflammation, apoptosis, and damage to DNA and tissue; likewise, these were prevented by high doses of Se. Taken with ACR, Se confers protection against ACR-induced nephrotoxicity in rats by reducing oxidative stress, inflammation, apoptosis, and DNA damage.

Quercetin regulates fibrogenic responses of endometrial stromal cell by upregulating miR-145 and inhibiting the TGF-β1/Smad2/Smad3 pathway

OBJECTIVES

Aim of this study is to explore whether quercetin can inhibit the enlarged fibrogenic responses of endometrial stromal cells by increasing the level of microRNA-145 (miR-145) and mediating the TGFβ1/Smad2/Smad3 signaling pathway, and to discuss the mechanism of signal transduction, further to provide experimental basis for revealing the pathophysiological mechanism and seeking new strategies for effective prevention and treatment of endometrial fibrosis.

METHODS

The expression levels of miR-145 and TGF-β receptor 2 (TGFBR2) were detected by RT-qPCR analysis. Expressions of α-smooth muscle actin (α-SMA) and vimentin were examined by immunofluorescence staining. Cell viability was measured by MTT assay. The protein expression of collagen type 1 alpha 1 (Col1a1), α-SMA, fibronectin (FN), TGFBR2, transforming growth factor (TGF-β1), Smad2/3, phospho-Smad2/3 (p-Smad2/3) were detected by western blot analysis. The interaction between miR-145 and TGFBR2 was confirmed by dual-luciferase reporter gene assay.

RESULTS

The expression level of miR-145 was decreased, whereas TGFBR2 was increased in intrauterine adhesion tissue. The expression levels of COL1A1, α-SMA, FN, TGFBR2, and p-Smad2/3 were increased, whereas miR-145 and cell proliferation were decreased in human endometrial stromal cells (hESCs) in response to TGF-β1 stimulation in a time and dose-dependent manner, which could be reversed by quercetin. Furthermore, quercetin regulates cell fibrogenic responses of endometrial stromal cells via miR-145/TGF-β1/Smad2/Smad3 pathway.

CONCLUSIONS

These findings indicated that quercetin have a significant anti-fibrotic effect and could upregulate miR-145 and inhibit activation of TGF-β1/Smad2/Smad3 pathway to regulate TGF-β1 induced fibrogenic responses of endometrial stromal cells, which may serve as a potential therapeutic agent for endometrial fibrosis.

Effects of Quercetin and Resveratrol on in vitro Properties Related to the Functionality of Potentially Probiotic Lactobacillus Strains

The ability of probiotics to exert benefits on host has been associated with different physiological functionalities in these microorganisms, namely cell surface hydrophobicity, autoaggregation, coaggregation with pathogens, antagonistic activity against pathogens and ability to survive the exposure to gastrointestinal conditions. This study assessed the effects of different concentrations of quercetin (QUE) and resveratrol (RES) on the ability of six potentially probiotic Lactobacillus strains to tolerate different pH values and bile salt concentrations, to autoaggregate, coaggregate with and antagonize pathogens and survive the exposure to simulated gastrointestinal conditions. QUE and RES presented low inhibitory effects on all tested Lactobacillus strains, with minimum inhibitory concentration (MIC) ranging from 512 to >1024 μg/mL. In most cases, QUE and RES at all tested concentrations (i.e., MIC, 1/2 MIC, and 1/4 MIC) did not affect the tolerance of the Lactobacillus strains to acidic pH and bile salts. QUE increased cell surface hydrophobicity of most of the tested Lactobacillus strains and increases or decreases in cell surface hydrophobicity varied in the presence of different RES concentrations among some strains. QUE and RES increased the ability of tested Lactobacillus strains to autoaggregate and coaggregate with pathogens. QUE and RES did not negatively affect the antagonistic activity of the tested Lactobacillus strains against pathogens and did not decrease their survival rates when exposed to in vitro gastrointestinal conditions. In a few cases, the ability of some tested Lactobacillus strains to antagonize pathogens, as well as to survive specific steps of the in vitro digestion was increased by QUE and RES. QUE exerted overall better protective effects on the measured in vitro properties of tested Lactobacillus strains than RES, and L. fermentum and L. plantarum strains presented better responses when treated with QUE or RES. These results showed that probiotic Lactobacillus strains could present low susceptibility to QUE and RES. Combined use of QUE and RES with probiotic Lactobacillus could improve their functionalities on the host; however, the concentration of these polyphenols should be carefully selected to achieve the desirable effects and vary according to the selected probiotic strain.

Quercetin is able to alleviate TGF-β-induced fibrosis in renal tubular epithelial cells by suppressing miR-21

Patients with chronic kidney disease (CKD) are characterized by a gradual loss of kidney function over time. A number of studies have indicated that tubule interstitial fibrosis (TIF) is associated with the occurrence and development of CKD. The aim of the present study was to investigate the effect of quercetin treatment on the fibrosis of renal tubular epithelial cells and to determine whether the anti-fibrotic effects of quercetin are achieved via microRNA (miR)-21. Human tubular epithelial HK-2 cells were cultured with transforming growth factor (TGF)-β to induce fibrosis and the expression of fibrotic markers collagen I, fibronectin, α-smooth muscle actin (SMA) and epithelial-cadherin were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. Cells were treated with 7.5, 15 or 30 mg/ml quercetin, following which fibrosis and miR-21 expression were evaluated. Quercetin-treated cells were transfected with miR-21 mimics and the expression of fibrotic markers was examined using RT-qPCR. Finally, the expression of fibrosis-associated miR-21 target genes, phosphatase and tensin homolog (PTEN) and TIMP Metallopeptidase Inhibitor 3 (TIMP3), was measured in cells treated with quercetin with or without miR-21 mimics using RT-qPCR, western blotting and immunocytochemistry. The results revealed that TGF-β treatment induced a significant increase in the expression of fibrotic markers in HK-2 cells, while quercetin treatment partially inhibited the fibrosis of HK-2 cells. Furthermore, quercetin treatment significantly inhibited TGF-β-induced miR-21 upregulation and transfection with miR-21 mimics reversed the anti-fibrotic effects of quercetin. Quercetin treatment markedly upregulated PTEN and TIMP3 expression, whereas transfection with miR-21 mimics reversed this effect. The results of the present study suggest that quercetin is able to alleviate TGF-β-induced fibrosis in HK-2 cells via suppressing the miR-21 and upregulating PTEN and TIMP3. Quercetin may have potential as an anti-fibrotic treatment for patients with renal fibrosis.

Quercetin inhibits glucose transport by binding to an exofacial site on GLUT1

Quercetin, a common dietary flavone, is a competitive inhibitor of glucose uptake and is also thought to be transported into cells by GLUT1. In this study, we confirm that quercetin is a competitive inhibitor of GLUT1 and also demonstrate that newly synthesized compounds, WZB-117 and BAY-876 are robust inhibitors of GLUT1 in L929 cells. To measure quercetin interaction with L929 cells, we develop a new fluorescent assay using flow cytometry. The binding of quercetin and its inhibitory effects on 2-deoxyglucose (2DG) uptake showed nearly identical dose dependent effects, with both having maximum effects between 50 and 100 μM and similar half maximum effects at 8.9 and 8.5 μM respectively. The interaction of quercetin was rapid with t_1/2 of 54 s and the onset and loss of its inhibitory effects on 2DG uptake were equally fast. This suggests that either quercetin is simply binding to surface GLUT1 or its transport in and out of the cell reaches equilibrium very quickly. If quercetin is transported, the co-incubation of quercetin with other glucose inhibitors should block quercetin uptake. However, we observed that WZB-117, an exofacial binding inhibitor of GLUT1 reduced quercetin interaction, while cytochalasin B, an endofacial binding inhibitor, enhanced quercetin interaction, and BAY-876 had no effect on quercetin interaction. Taken together, these data are more consistent with quercetin simply binding to GLUT1, but not actually being transported into L929 cells via the glucose channel in GLUT1.

Anaphylatoxin C5a induces inflammation and reduces insulin sensitivity by activating TLR4/NF-kB/PI3K signaling pathway in 3T3-L1 adipocytes

Obesity closely correlates with metaflammation and characterizes with systemic-chronic-low inflammation. This study aims to evaluate effects of C5a on the inflammatory response and insulin resistance in 3T3-L1 adipocytes. 3T3-L1 pre-adipocytes were induced to the mature 3T3-L1 adipocytes. Then, 3T3-L1 were intervened with anaphylatoxin C5a, lipopolysaccharide (LPS) and C5a + LPS, respectively. Levels of Omentin, Chemerin, Vaspin and Apelin 12 in supernatants of medium were examined using ELISA. C5L2, C5a receptor (C5aR), I kappa B (IkB), IkB kinase (IKK), insulin receptor substrate 1 (IRS-1), IRS-2, PI3 K, p-PI3 K and β-actin were examined using RT-PCR and western blot assay, respectively. C5L2-C5aR colocalization was identified using immunofluorescence double label. NF-kB expression or activity was evaluated using electrophoretic mobility shift assay (EMSA), dual luciferase assay and immunofluorescence assay, respectively. The glucose uptake and insulin sensitivity were also evaluated. Results showed that C5a intervention significantly enhanced inflammatory molecule levels in supernatants of 3T3-L1 adipocytes. IKK inflammatory signaling pathway participated in C5a induced inflammation of 3T3-L1 adipocytes. C5a triggered the colocalization of C5L2 and C5aR and activated the NF-kB inflammatory signaling pathway. C5a intervention in 3T3-L1 adipocytes decreased the glucose uptake and resulted in reduction of insulin sensitivity. Insulin signaling pathway participated in C5a caused insulin sensitivity reduction. C5a intervention triggered the phosphorylation of PI3 K. In conclusion anaphylatoxin C5a induced inflammatory response by activating TLR4/NF-kB signaling pathway and generating C5L2-C5aR dimer, and caused insulin sensitivity reduction by activating PI3 K signaling pathway.