Antioxidant activity, antitumor effect, and antiaging property of proanthocyanidins extracted from Kunlun Chrysanthemum flowers

Study on the antithrombotic effect and physiological mechanism of okanin

The objectives of this study were to investigate the antithrombotic effect and physiological mechanism of okanin, a flavonoid monomer in Coreopsis tinctoria Nutt. The antithrombotic effects of okanin were determined by the anticoagulant activity test in vitro and in vivo, the venous thrombosis and arterial thrombosis test in rats. To study the antithrombotic physiological mechanisms of okanin, UV spectrophotometer and enzyme-linked immunosorbent assay (ELISA) were used to determine the effects of three concentrations of okanin on the contents of 6-keto-prostaglandin F1α (6-Keto-PGF_1α), thromboxane B₂ (TXB₂), endothelin-1 (ET-1), antithrombin III (AT-Ⅲ), protein C (PC) and von willebrand factor (vWF) in the plasma of rats with arterial thrombosis; ELISA was used to detect the effects of okanin on the contents of plasminogen (PLG), tissue plasminogen activator (t-PA) and type-1 plasminogen activator inhibitor (PAI-1) in the plasma of mice and Chinese white rabbits. The results showed that okanin could prolong the coagulation time in vitro and in vivo of animals (P < 0.01 in the high dose group) and the activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) of human venous blood (ATPP of medium dose group P < 0.01; PT, TT P < 0.05. P < 0.01 in the high dose group); inhibit the maximum platelet aggregation rate of rabbits (P < 0.05 in the low dose group; P < 0.01 in the medium and high dose groups), decrease the dry and wet weight of venous thrombosis and the wet weight of common carotid artery thrombosis in rats (low dose group, P < 0.05; medium and high dose groups, P < 0.01); increase the levels of 6-Keto-PGF_1α, AT-Ⅲ, PLG and t-PA in animal plasma; decrease the levels of TXB₂, ET-1, vWF and PAI-₁ in animal plasma. It is concluded that okanin can significantly inhibit thrombosis, and its physiological mechanisms were related to affecting the activation of related coagulation factors in endogenous and exogenous coagulation pathways, affecting the physiological characteristics of platelets, repairing damaged vascular endothelial cells and enhancing the activity of the fibrinolytic system.

The Antitumor Effect and Mechanism of Total Flavonoids From Coreopsis Tinctoria Nutt (Snow Chrysanthemum) on Lung Cancer Using Network Pharmacology and Molecular Docking

Coreopsis tinctoria Nutt (C. tinctoria), also known as Snow Chrysanthemum, is rich in polyphenols and flavonoids. It has important pharmacological effects such as lowering blood lipids, regulating blood glucose, and anti-tumor effect. However, its anti-tumor mechanism has not yet been investigated thoroughly. This study aimed to explore the anti-tumor effect of total flavonoids extracted from C. tinctoria (CTFs) on lung cancer and the possible mechanism. The components of CTFs were analyzed using Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The active components of CTFs were screened according to oral bioavailability (OB) and drug-likeness (DL). Totally, 68 components of CTFs were identified and 23 active components were screened. Network pharmacological analysis on the active components identified 288 potential targets associated with lung cancer. After protein-protein interaction (PPI) network topology analysis, 17 key protein targets including Akt1, MAPK1, TP53, Bcl-2, Caspase-3, Bax, GSK3B and CCND1 were screened. The molecular docking results showed that the active components of CTFs had good binding activity with key targets. GO and KEGG analysis of candidate targets found that the main enrichment was in PI3K/Akt-mediated intrinsic apoptotic pathways. Finally, according to the results of network pharmacology, the potential molecular mechanism of CTFs intervention in lung cancer was validated experimentally in vitro and in vivo. The experimental validation results demonstrated that the antitumor activity of CTFs on lung cancer may be related to inhibiting the PI3K-Akt signaling pathway and activating the mitochondrial-mediated apoptosis pathway.

Enhanced bioavailability and anti-hyperglycemic activity of young apple polyphenols by complexation with whey protein isolates

This study aims to evaluate the effects of complexation of whey protein isolate (WPI) and young apple polyphenols (YAP) on the bioavailability and anti-hyperglycemic activity of YAP. Two types of WPI-YAP complexes were fabricated by mixing WPI with YAP at 25℃ (WPI-YAP) and 90℃ (WPI-YAP-H), respectively. The intermolecular interactions between WPI and YAP were investigated by fluorescence spectroscopy and circular dichroism analyses. The in vitro bioaccessibility and bioavailability of YAP were determined using a simulated gastrointestinal digestion and human Caco-2 cells model. It was found that the total polyphenols transport efficiency was improved from 39.8% (YAP) to 48.2% (WPI-YAP) and 56.1% (WPI-YAP-H), indicating that the bioavailability of YAP was improved by complexation with WPI. Besides, after complexation with WPI, YAP displayed an improved in vivo effect on alleviating the increase in postprandial blood glucose level than the pure YAP, with WPI-YAP-H showing a better effect. This finding indicates that co-complexation of YAP with WPI is an effective way to improve the functionality of YAP, and the WPI-YAP complexes are also expected to have potential application in designing YAP-containing functional foods. PRACTICAL APPLICATION: The research provided a method to improve the bioavavibility of polyphenols, and the WPI-YAP complex can be developed in designing polyphenols related functional foods.

Antioxidative and Hypoglycemic Effect of Ta-ermi Extracts on Streptozotocin-Induced Diabetes

INTRODUCTION

The purpose of the present study was to reveal the potential positive effect of the Ta-ermi extracts on oxidative stress and streptozotocin (STZ)-diabetic mice and rats treated with Ta-ermi water- and alcohol-extracts.

METHODS

The study was carried out using three experimental model: 1) in vitro experiments whereby Ta-ermi extracts were incubated with free radical generators such as 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) to evaluate Ta-ermi's antioxidant effects; 2) testing the hypoglycemic effects of Ta-ermi extracts in streptozotocin (STZ)-induced diabetic mice; and 3) testing the beneficial effects of Ta-ermi extracts on mitochondrial complex I function using STZ-diabetic rats.

RESULTS

In vitro antioxidant experiments showed that both of the extracts could scavenge free radicals and exhibited inhibitory effects on glucosidase and aldose reductase with differential effects between water extract and alcohol extract. In the STZ mouse diabetic model, both the water- and alcohol-extracts attenuated body weight decrease, decreased blood glucose levels in a concentration-dependent manner, improved insulin sensitivity, and increased oral glucose tolerance ability. In the STZ-diabetic rat model, both the water- and alcohol-extracts were found to be able to lower blood glucose levels in the diabetic animals with no effects on body weight changes. Moreover, in the STZ-diabetic rats, both the water- and alcohol-extracts of Ta-ermi could inhibit the increase of mitochondrial NADH/ubiquinone oxidoreductase (complex I) activity in the pancreas and enhanced complex I activity in the liver but showed no effect on lung or kidney mitochondrial complex I.

DISCUSSION

The present study points to the potential medicinal value of Ta-ermi's water and alcohol extracts in lowering blood glucose and decreasing diabetic oxidative stress. One limitation of our study is that the compound or compounds that actually have this beneficial effect in the extracts remain unknown at this time. Therefore, the future studies should be focused on the identification of the components in the extracts that exhibit anti-oxidative and hypoglycemic effects.

CONCLUSION

Taken together, our studies using different experimental paradigms indicate that Ta-ermi extracts possess antioxidant and anti-diabetic properties and may be employed as functional food ingredients for the remission of diabetes.

Interaction between soybean protein and tea polyphenols under high pressure

Tea polyphenols (TP) and soybean proteins (SP) are important materials in food industry. High hydrostatic pressure (HHP) is a useful tool for improvement of protein's function. This study evaluated the interactions between the polyphenol and HHP-treated protein using circular dichroism, fluorescence spectroscopy and molecular modeling. The high pressure at 400 MPa significantly modified the secondary structure of SP by increasing the β-sheet content and decreasing the α-helix content, while the addition of 0.1% (w/v) tea ployphenol appeared to protect the α-helix structure. The surface hydrophobicity decreased with HHP treatment and the addition of TP. The optimal solubility of native SP was 0.258 g/mL at 0.08% (w/v) TP. Together with HHP treatment; TP increased the protein solubility to 0.50 g/mL and the emulsifying activity was enhanced approximately three times, up to 43.5%. The micro-texture of SP matrix was also improved with TP and HHP treatment. Both the hydrogen bonding and hydrophobic interaction between TP and SP were elucidated using docking method. Apart from the hydrogen bonding, the Pi-Pi interaction was observed in the binding of phenolic compounds to 7S or 11S globular protein.

Synergistic Effects of Resveratrol and Pyrimethanil against Botrytis cinerea on Grape

Botrytis cinerea is the pathogen of gray mold disease affecting a wide range of plant hosts, with consequential economic losses worldwide. The increased frequency of fungicide resistance of the pathogen challenges its disease management, and thus the development of alternative control strategies are urgently required. In this study, we showed excellent synergistic interactions between resveratrol and pyrimethanil. Significant synergistic values were recorded by the two-drug combination on the suppression of mycelial growth and conidia germination of B. cinerea. The combination of resveratrol and pyrimethanil caused malformation of mycelia. Moreover, the inoculation assay was conducted on table grape and consistent synergistic suppression of the two-drug combination was found in vivo. Our findings first revealed that the combination of resveratrol and pyrimethanil has synergistic effects against resistant B. cinerea and support the potential use of resveratrol as a promising adjuvant on the control of gray mold.

Orthogonal Array composite design to study and optimize antioxidant combinations in the prevention of UVB-induced HSF damage

Excessive exposure to ultraviolet (UV) B radiation may lead to skin damage, photosensitivity, or even tumorigenesis via induction of oxidative stress. Naturally derived antioxidants could play significant roles in cancer therapy due to their multi-targeted actions and lack of substantial toxicity. Drug combinations target at diverse pathway of cells and make cells export meticulous biological outcomes through the multifaceted signaling network. The UVB protective effects of combinations of naturally derived antioxidants- curcumin, resveratrol, proanthocyanidins, baicalein, and beta-nicotinamide adenine dinucleotide (NADH) were investigated. An oxidative cell damage model was established to study the ultraviolet irradiation system. An orthogonal array composite design (OACD) was employed in the optimization of antioxidants combinations. Combination of resveratrol (0.1μM) and baicalein in medium concentration (0.2μM), with NADH in high concentration (0.8μM) was found to be the most efficacious combination among all the 30 runs performed using OACD. The findings suggested that UVB exposure-inflicted cell apoptosis can be significantly reduced by naturally-derived antioxidant combinations. These results provide an insight into the discovery of synergistic antioxidant combinations in skin cancer, using orthogonal array composite design (OACD). The results also have practical implications in the understanding of drug mechanisms in skin cancer, which can assist clinical practice by recommending better drug combinations.

Nanoethosomal formulation of gammaoryzanol for skin-aging protection and wrinkle improvement: a histopathological study

BACKGROUND

Free radical scavengers and antioxidants, with the main focus on enhanced targeting to the skin layers, can provide protection against skin ageing.

OBJECTIVE

The aim of the present study was to prepare nanoethosomal formulation of gammaoryzanol (GO), a water insoluble antioxidant, for its dermal delivery to prevent skin aging.

METHODS

Nanoethosomal formulation was prepared by a modified ethanol injection method and characterized by using laser light scattering, scanning electronic microscope (SEM) and X-ray diffraction (XRD) techniques. The effects of formulation parameters on nanoparticle size, encapsulation efficiency percent (EE%) and loading capacity percent (LC%) were investigated. Antioxidant activity of GO-loaded formulation was investigated in vitro using normal African green monkey kidney fibroblast cells (Vero). The effect of control and GO-loaded nanoethosomal formulation on superoxide dismutase (SOD) and malondialdehyde (MDA) content of rat skin was also probed. Furthermore, the effect of GO-loaded nanoethosomes on skin wrinkle improvement was studied by dermoscopic and histological examination on healthy humans and UV-irradiated rats, respectively.

RESULTS

The optimized nanoethosomal formulation showed promising characteristics including narrow size distribution 0.17 ± 0.02, mean diameter of 98.9 ± 0.05 nm, EE% of 97.12 ± 3.62%, LC% of 13.87 ± 1.36% and zeta potential value of -15.1 ± 0.9 mV. The XRD results confirmed uniform drug dispersion in the nanoethosomes structure. In vitro and in vivo antioxidant studies confirmed the superior antioxidant effect of GO-loaded nanoethosomal formulation compared with control groups (blank nanoethosomes and GO suspension).

CONCLUSIONS

Nanoethosomes was a promising carrier for dermal delivery of GO and consequently had superior anti-aging effect.

Chrysanthemum morifolium extract improves hypertension-induced cardiac hypertrophy in rats by reduction of blood pressure and inhibition of myocardial hypoxia inducible factor-1alpha expression

CONTEXT

Chrysanthemum morifolium Ramat. (Asteraceae) extract (CME) possesses a vasodilator effect in vitro. However, the use of polyphenol-rich CME in the treatment of hypertension-induced cardiac hypertrophy has not been reported.

OBJECTIVE

We investigated the effect of polyphenol-rich CME on hypertension-induced cardiac hypertrophy in rats and its possible mechanism of action.

MATERIALS AND METHODS

The Sprague-Dawley rat model with cardiac hypertrophy was induced by renovascular hypertension. The blood pressure, cardiac weight index, free fatty acids (FFA) in serum and myocardium, and protein expressions of myocardial hypoxia inducible factor-1α (HIF-1α), peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyltransferase-1a (CPT-1a), pyruvate dehydrogenase kinase-4 (PDK-4) and glucose transporter-4 (GLUT-4) were measured after treating hypertensive rats with polyphenol-rich CME of anthodia 75-150 mg/kg once daily for 4 weeks. A myocardial histological examination was also conducted.

RESULTS

After CME treatment, the blood pressure, cardiac weight and cardiac weight index decreased by 5.7-9.6%, 9.2-18.4% and 10.9-20.1%, respectively, and the cardiomyocyte cross-sectional area also decreased by 8.3-30.4%. The CME treatment simultaneously decreased the FFA in serum and myocardium and protein expressions of myocardial HIF-1α and GLUT-4, and increased the protein expressions of myocardial PPARα, CPT-1a and PDK-4, especially in the CME 150 mg/kg group (p < 0.05 or p < 0.01).

DISCUSSION AND CONCLUSION

Polyphenol-rich CME may alleviate hypertensive cardiac hypertrophy in rats. Its mechanisms may be related to the reduction of blood pressure and amelioration of the myocardial energy metabolism. The latter may be attributed to the inhibition of HIF-1α expression and subsequent modulation of PPARα-mediated CPT-1a, PDK-4 and GLUT-4 expressions.

Inhibitory actions of selected natural substances on formation of advanced glycation endproducts and advanced oxidation protein products

Background

Advanced glycation endproducts (AGE) and advanced oxidation protein products (AOPP) arise as a result of excessive glycation and oxidation processes of proteins in hyperglycemia and oxidative stress conditions respectively, both in vivo and in vitro. In vivo these processes are especially intensified in patients with diabetes, and the adverse effects of AGE and AOPP are particularly unfavorable for the pathogenesis and aggravate the biochemical disturbances and clinical complications of diabetes. Total AGE and AOPP (T-AGE and T-AOPP) are heterogeneous groups of compounds, and they can be divided into two main fractions: high- and low-molecular-weight, i.e. HMW-AGE and HMW-AOPP as well as LMW-AGE and LMW-AOPP. Therefore it is important to find natural substances that will prevent formation of total AGE and AOPP and their high- and low-molecular-weight fractions and thereby reduce their adverse effects on tissues and organs.

Method

Selected natural substances and dietary supplements such as vitamin C, aminoguanidine, quercetin and green tea as well as the multicompound formulations Padma Circosan and Padma 28 were tested in an in vitro model using bovine serum albumin (BSA). Fluorescence of T-, HMW- and LMW-AGE and concentration of T-, HMW- and LMW-AOPP were measured after incubation with these substances.

Results

In the examined concentrations quercetin showed the greatest degree of inhibition for T-AGE (60.5 %) as well as for HMW-AGE (79.5 %), while in the case of LMW-AGE the greatest degree of glycation inhibition was shown by Padma Circosan (74.9 %). T-AOPP and HMW-AOPP were best inhibited by vitamin C (87.3 and 89.1 % respectively). The results obtained for LMW-AOPP are atypical, but the lowest concentration was observed in a sample with Padma 28.

Conclusion

The results show that all tested natural compounds have inhibitory activity towards the formation of total and low- and high-molecular-weight forms of AGE and AOPP in vitro. That suggest a possible role in the prevention of diabetic complications, especially the multiherbal compound Padma preparations, which are especially effective in lowering the most dangerous, i.e. LMW fractions.