Myricetin modulates streptozotocin–cadmium induced oxidative stress in long term experimental diabetic nephrotoxic rats

The seamless integration of dietary plant-derived natural flavonoids and gut microbiota may ameliorate non-alcoholic fatty liver disease: a network pharmacology analysis

We comprised metabolites of gut microbiota (GM; endogenous species) and dietary plant-derived natural flavonoids (DPDNFs; exogenous species) were known as potent effectors against non-alcoholic fatty liver disease (NAFLD) via network pharmacology (NP). The crucial targets against NAFLD were identified via GM and DPDNFs. The protein interaction (PPI), bubble chart and networks of GM or natural products- metabolites-targets-key signalling (GNMTK) pathway were described via R Package. Furthermore, the molecular docking test (MDT) to verify the affinity was performed between metabolite(s) and target(s) on a key signalling pathway. On the networks of GNMTK, Enterococcus sp. 45, Escherichia sp.12, Escherichia sp.33 and Bacterium MRG-PMF-1 as key microbiota; flavonoid-rich products as key natural resources; luteolin and myricetin as key metabolites (or dietary flavonoids); AKT Serine/Threonine Kinase 1 (AKT1), CF Transmembrane conductance Regulator (CFTR) and PhosphoInositide-3-Kinase, Regulatory subunit 1 (PIK3R1) as key targets are promising components to treat NAFLD, by suppressing cyclic Adenosine MonoPhosphate (cAMP) signalling pathway. This study shows that components (microbiota, metabolites, targets and a key signalling pathway) and DPDNFs can exert combinatorial pharmacological effects against NAFLD. Overall, the integrated pharmacological approach sheds light on the relationships between GM and DPDNFs.

Rapid Characterization and Action Mechanism of the Antidiabetic Effect of Diospyros lotus L Using UHPLC-Q-Exactive Orbitrap MS and Network Pharmacology

Diospyros lotus L, F. Ebenaceae, is an edible fruit that is widely distributed in China and other Asian countries. Presently, Diospyros lotus L can be used to treat patients with diabetes; however, its chemical composition and pharmacological profiles remain to be elucidated. This study investigated the potential bioactive compounds of Diospyros lotus L and their mechanisms of action using LC-MS and network pharmacology analysis. First, the components of Diospyros lotus L were identify using a reliable strategy for UHPLC-Q-Exactive Orbitrap mass spectrometry combined with parallel reaction monitoring (PRM) in the negative ion mode. Second, a network pharmacology study, including target gene prediction and functional enrichment, was applied to screen the main quality markers of Diospyros lotus L and explore its potential mechanism for the treatment of diabetes. The results showed that a total of 159 compounds were identified from Diospyros lotus L, among which, 140 were reported for the first time. Furthermore, 40 active components, such as quercetin, luteolin, and kaempferol, were proposed as active components of Diospyros lotus L for the treatment of diabetes based on network pharmacology analysis. In addition, 92 relevant antidiabetic targets were mainly related to positive regulation of transcription from the RNA polymerase II promoter, extracellular space, and protein binding, suggesting the involvement of TNF, PI3K-Akt, and HIF-1 signaling pathways in the antidiabetic effect of Diospyros lotus L. Our results may provide a useful approach to identify potential active components and molecular mechanisms of Diospyros lotus L for the treatment of diabetes.

Myricetin loaded nano-micelles delivery system reduces bone loss induced by ovariectomy in rats through inhibition of osteoclast formation

In recent years, much attention has been paid to the therapeutic effects of phytochemicals on osteoporosis. Other studies have shown that myricetin (MY) could promote osteogenic activity and inhibit osteoclastic effect, albeit little is known about effect of MY micellar system on osteoporosis. Therefore, we sought to discuss the therapeutic effect and mechanism of MY-loaded bone-targeting micelles on osteoporosis induced by ovariectomy (OVA) in rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles were prepared via ethanol injection method, while in vitro release study, bone targeting, pharmacokinetic studies, and the effect on proliferation of osteoblasts were investigated. Further, the therapeutic effect on osteoporosis was studied through ovariectomized rats. Compared with free MY, oral bioavailability of AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles in rats was increased by 3.54 times. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles exhibited bone targeting potential, and could significantly increase the activity of alkaline phosphatase and promote the proliferation of osteoblasts. Importantly, AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles mainly regulated bone metabolism by inhibiting bone resorption, thereby improving the symptoms of osteoporosis in OVA rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles substantially enhanced the oral bioavailability of MY and demonstrated good bone targeting capability, thereby suggesting its prospect as carrier for osteoporotic improvement in OVA rats.

Cyperus iria aqueous-ethanol extract ameliorated hyperglycemia, oxidative stress, and regulated inflammatory cytokines in streptozotocin-induced diabetic rats

Type 2 diabetes mellitus is a complicated metabolic disorder with no definite treatment. Cyperus iria (Cyperaceae) possess several traditional therapeutic uses. According to the folklore tales, the whole plant of Cyperus iria possesses antihyperglycemic activity. The present study was undertaken to investigate whether aqueous-ethanol extract of Cyperus iria can ameliorate the altered activities of carbohydrate metabolism in streptozotocin (STZ)-induced diabetic rats along with appraisal of inflammatory and stress markers involved in endocrine dysfunction. Presence of biophenolics and flavonoids might be responsible for the antidiabetic potential. STZ-induced diabetic rats were treated orally with Cyperus iria extract (125, 250, and 500 mg/kg) for 15 days. Blood samples were collected. Metformin was used as positive control. Significantly higher quantities of phenolic (82.79±0.003 mg/g GAE) and flavonoid (13.61±0.002 mg/g QE) contents were present. Inhibitory concentration (IC50) exhibited an excellent potential for both antioxidant (IC50= 3.22 μg/mL) and alpha amylase (IC50=36.29 μg/mL) inhibitory assays. High-performance liquid chromatography (HPLC) confirmed the existence of myercetin, quercetin, kaempferol, and ferulic acid. Cyperus iria aqueous-ethanol extract exhibits good tolerance against glucose at 90 min in normal rats. Streptozotocin-induced hyperglycemia declined significantly at day 9 (265 mg/dL) along with improvement in inflammatory (TNF-α=15.6± 0.2 g/l, COX-2=357±0.396 U/l, IL-6= 572±0.99 pg/l) and oxidative stress markers (SOD= 163±0.616 and GSH-ST= 95.8±0.44 U/mL) along with biochemical parameters in a dose-dependent manner. Present study suggests that Cyperus iria aqueous-ethanol extract possesses hypoglycemic potential which might be attributed to the decrease in oxidative stress and inflammatory markers.

Myricetin: A comprehensive review on its biological potentials

Myricetin is a critical nutritive component of diet providing immunological protection and beneficial for maintaining good health. It is found in fruits, vegetables, tea, and wine. The families Myricaceae, Polygonaceae, Primulaceae, Pinaceae, and Anacardiaceae are the richest sources of myricetin. Different researchers explored the therapeutic potential of this valuable constituent such as anticancer, antidiabetic, antiobesity, cardiovascular protection, osteoporosis protection, anti-inflammatory, and hepatoprotective. In addition to these, the compound has been tested for cancer and diabetic mellitus during clinical trials. Health benefits of myricetin are related to its impact on different cell processes, such as apoptosis, glycolysis, cell cycle, energy balance, lipid level, serum protein concentrations, and osteoclastogenesis. This review explored the potential health benefits of myricetin with a specific emphasis on its mechanism of action, considering the most updated and novel findings in the field.

Myricetin bioactive effects: moving from preclinical evidence to potential clinical applications

Several flavonoids have been recognized as nutraceuticals, and myricetin is a good example. Myricetin is commonly found in plants and their antimicrobial and antioxidant activities is well demonstrated. One of its beneficial biological effects is the neuroprotective activity, showing preclinical activities on Alzheimer, Parkinson, and Huntington diseases, and even in amyotrophic lateral sclerosis. Also, myricetin has revealed other biological activities, among them as antidiabetic, anticancer, immunomodulatory, cardiovascular, analgesic and antihypertensive. However, few clinical trials have been performed using myricetin as nutraceutical. Thus, this review provides new insights on myricetin preclinical pharmacological activities, and role in selected clinical trials.

The Protective Effects of Myricetin against Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death globally, except Africa, and poses a severe health burden worldwide. Both in vitro and in vivo studies have demonstrated the protective effects of myricetin for preventing CVD. For this review, we have assessed the literature from 2009 to 2019 at home and abroad to uncover the protective roles of myricetin for preventing CVD. Myricetin exhibits cardioprotective, anti-hypertensive, anti-atherosclerotic, anti-hyperglycemic, and anti-hyperlipidemic effects. In addition, myricetin may alleviate some of the complications caused by adult-onset diabetes. The combined functions of myricetin allow for the prevention of CVD. This review describes the possible therapeutic benefits of myricetin, along with its potential mechanisms of action, to support the clinical use of the myricetin for the prevention of CVD.

Beneficial Effects of Dietary Polyphenols on High-Fat Diet-Induced Obesity Linking with Modulation of Gut Microbiota

Obesity is caused by an imbalance of energy intake and expenditure. It is characterized by a higher accumulation of body fat with a chronic low-grade inflammation. Many reports have shown that gut microbiota in the host plays a pivotal role in mediating the interaction between consumption of a high-fat diet (HFD) and onset of obesity. Accumulative evidence has suggested that the changes in the composition of gut microbiota may affect the host's energy homeostasis, systemic inflammation, lipid metabolism, and insulin sensitivity. As one of the major components in human diet, polyphenols have demonstrated to be capable of modulating the composition of gut microbiota and reducing the HFD-induced obesity. The present review summarizes the findings of recent studies on dietary polyphenols regarding their metabolism and interaction with bacteria in the intestine as well as the underlying mechanisms by which they modulate the gut microbiota and alleviate the HFD-induced obesity.

Metabolomics study of cadmium-induced diabetic nephropathy and protective effect of caffeic acid phenethyl ester using UPLC-Q-TOF-MS combined with pattern recognition

Diabetic nephropathy (DN) is the most severe complication of diabetes and multiple factors are involved in the pathogenesis of DN. Among them, cadmium (Cd) acts as a risk factor inducing the occurrence of DN. The present study focused on investigating the protective role of caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, against Cd-induced DN in mice based on ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS)and pattern recognition. Serum and urine biochemical indexes were detected and histopathological observation has been done to evaluate the damage of Cd on animals. Moreover, the global serum profiles of different groups were distinguished by UPLC-Q-TOF-MS and principal component analysis (PCA) were applied for group differentiation and marker selection. Moreover, the influence of Cd on the oxidative status in DN mice were also evaluated by assessing the parameters of oxidative stress, proinflammatory cytokines and antioxidant competence. As shown in the scores plots, the distinct clustering among controls, DN and CAPE groups were observed, significant changes in serum levels of LysoPC(18:1(11Z)), 2,3-dinor-8-iso-PGF2a, PS(18:1(9Z)/18:1(9Z)), DG(17:0/22:4 (7Z,10Z, 13Z, 16Z)/0:0) and Arachidonic acid(AA) were noted and identified as potential biomarkers, the effect of CAPE reverted them back to near normalcy. Further, It was observed a significant improvement in lipid peroxides (LPO) and protein carbonyls (PCO) levels in Cd-induced DN kidneys along with a significant decline in superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) levels, however, CAPE relieved these changes. In conclusion, the study suggested that the pathogenesis of DN caused by Cd probably owes to the perturbations of lipid metabolism and AA metabolism; CAPE seems to be effective agent and may be related to its potent antioxidant, anti-inflammatory properties and action as an Nrf2 activator.

Assessment of the Anti-Hyperglycaemic, Anti-Inflammatory and Antioxidant Activities of the Methanol Extract of Moringa Oleifera in Diabetes-Induced Nephrotoxic Male Wistar Rats

Diabetes mellitus is an endocrine disease of multiple aetiologies in insulin secretion. A deficiency in insulin results in hyperglycemia with metabolic disturbances of biomolecules. Moringa oleifera (MO) is endemic in the tropics with a variety of ethnomedicinal importance. The leaf of this plant has been reported to possess antioxidant and medicinal properties that may be helpful in the treatment and management of diabetes and its associated complications. Diabetes was induced intraperitoneally in rats by a single dose of streptozotocin (55 mg/kg) and treated with methanolic extract of Moringa oleifera (250 mg/kg b.wt) for six weeks. Forty-eight (48) adult male Wistar strain rats were randomly divided into four groups: normal control (NC), Moringa oleifera treated control rats (NC + MO), diabetic rats (DM) and Moringa oleifera treated diabetic rats (DM + MO). Estimation of antioxidant capacity, total polyphenols, flavonoids and flavonols content of Moringa oleifera extract was performed and serum biochemical markers were evaluated. Antioxidants such as catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) activities, glutathione (GSH) and inflammatory biomarkers were determined in the kidney. Results showed high antioxidant capacities of MO extract and improved serum biochemical markers, whilst lipid peroxidation (MDA) levels were reduced in non-diabetic and diabetic rats after MO treatment when compared to normal control. Subsequent administration of MO led to an increased concentration of serum albumin, globulin and total protein with a decrease in the level of MDA, and improvements in CAT, SOD, GSH, GPx, (tumour necrosis factor-alpha)TNF-α and (interleukin-6)IL-6. MO contains potent phytochemical constituents that offer protective action against diabetic-induced renal damage, reactive oxygen species (ROS) and inflammation and could therefore play a role in reducing diabetic complications, particularly in developing countries such as in Africa where the majority cannot afford orthodox medicine.

Myricetin: A Dietary Molecule with Diverse Biological Activities

Myricetin is a common plant-derived flavonoid and is well recognised for its nutraceuticals value. It is one of the key ingredients of various foods and beverages. The compound exhibits a wide range of activities that include strong anti-oxidant, anticancer, antidiabetic and anti-inflammatory activities. It displays several activities that are related to the central nervous system and numerous studies have suggested that the compound may be beneficial to protect against diseases such as Parkinson's and Alzheimer's. The use of myricetin as a preserving agent to extend the shelf life of foods containing oils and fats is attributed to the compound's ability to protect lipids against oxidation. A detailed search of existing literature revealed that there is currently no comprehensive review available on this important molecule. Hence, the present work includes the history, synthesis, pharmaceutical applications and toxicity studies of myricetin. This report also highlights structure-activity relationships and mechanisms of action for various biological activities.

Dietary compounds galangin and myricetin suppress ovarian cancer cell angiogenesis

Galangin and myricetin are flavonoids isolated from vegetables and fruits which exhibit anti-proliferative activity in human cancer cells. In this study, their anti-angiogenic effects were investigated with in vitro (HUVEC) and in vivo (CAM) models, which showed that galangin and myricetin inhibited angiogenesis induced by OVCAR-3 cells. The molecular mechanisms through which galangin and myricetin suppress angiogenesis were also studied. It was observed that galangin and myricetin inhibited secretion of the key angiogenesis mediator vascular endothelial growth factor (VEGF) and decreased levels of p-Akt, p-70S6K and hypoxia-inducible factor-1α (HIF-1α) proteins in A2780/CP70 and OVCAR-3 cells. Transient transfection experiments showed that galangin and myricetin inhibited secretion of VEGF by the Akt/p70S6K/ HIF-1α pathway. Moreover, a novel pathway, p21/HIF-1α/VEGF, was found to be involved in the inhibitory effect of myricetin on angiogenesis in OVCAR-3 cells. These data suggest that galangin and myricetin might serve as potential anti-angiogenic agents in the prevention of ovarian cancers dependent on new blood vessel networks.

Myricetin derived from Hovenia dulcis Thunb. ameliorates vascular endothelial dysfunction and liver injury in high choline-fed mice

The present study was conducted to explore the protective effects of myricetin (MYR) purified from Hovenia dulcis Thunb. against vascular endothelial dysfunction and liver injury in mice fed with 3% dietary choline water.

Total nutritional capacity and inflammation inhibition effect of Acalypha alnifolia Klein ex wild—An unexplored wild leafy vegetable

Investigation of the nutritional as well as trace elements of a wild leafy vegetable, Acalypha alnifolia, and evaluation of the analgesic, anti-inflammatory, and antipyretic properties of acetone and methanol leaf extracts are the main objectives of the present study. The powdered A. alnifolia leaf sample was subjected to nutritional and mineral analysis. Plant leaves were extracted (using the Soxhlet apparatus) as successive solvent extractions. The extract doses of 200 and 400 mg/kg of acetone and methanol extracts were used for pharmacology study. The analgesic, anti-inflammatory, and antipyretic experiments were carried out by using animal models. The obtained result proves that the plant possesses essential nutritive values and useful biological properties. The higher dose of acetone extract has significant potency when compared with methanol extract at p < 0.005. On the whole, the plant is rich in minerals and has good biological properties; hence, this plant is suggested for cultivation and regular use for nutritional supplement.

Renoprotective effect of myricetin restrains dyslipidemia and renal mesangial cell proliferation by the suppression of sterol regulatory element binding proteins in an experimental model of diabetic nephropathy

Myricetin is a natural flavonoid used in various health management systems. In this present study myricetin tested to evaluate the effect on lipids and lipid metabolism enzymes in normal and streptozotocin (STZ) with cadmium (Cd) induced diabetic nephrotoxic rats. Diabetic nephrotoxic rats were significantly (P<0.05) increased the levels of urinary albumin and lipid profiles: total cholesterol (TC), triglycerides (TGs), free fatty acids (FFAs), phospholipids (PLs), low density lipoprotein (LDL), very low-density lipoproteins (VLDL), and decreased in the levels of high-density lipoproteins (HDL). In addition, the activity of lipoprotein lipase (LPL) and lecithin cholesterol acyl transferase (LCAT) were decreased significantly, whereas the 3-hydroxy 3-methylglutaryl coenzyme A (HmgCoA) reductase activity was increased. The upregulation of sterol regulatory element binding protein-1a (SREBP-1a), SREBP-1c, SREBP-2, transforming growth factor-β1 (TGF-β1), vascular endothelial growth factor (VEGF) and downregulation peroxisome proliferator-activated receptor alpha (PPAR-α) proteins expression levels were noticed. An administration of myricetin (1.0 mg/kg body weight (b/w)) for 12 weeks was brought the above parameters towards normal level. Histopathological study of kidney samples showed that extracellular mesangial matrix expansion, glomerulosclerosis and interstitial fibrosis in diabetic nephrotoxic rats was suppressed by myricetin treatment. Further our results indicate that administration of myricetin afforded remarkable protection against STZ-Cd induced alterations in lipid metabolism and thereby reduced the diabetic nephropathy in experimental rats.