scholarly journals Mechanism of Action and Interactions between Thyroid Peroxidase and Lipoxygenase Inhibitors Derived from Plant Sources

Biomolecules ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 663
Author(s):  
Ewa Habza-Kowalska ◽  
Urszula Gawlik-Dziki ◽  
Dariusz Dziki

This study focused on the effect of kaempferol, catechin, apigenin, sinapinic acid, and extracts from plants (i.e., parsley, cumin, mustard, green tea, and green coffee) on thyroid peroxidase (TPO) and lipoxygenase (LOX) activity, antiradical potential, as well as the result of interactions among them. Catechin, sinapinic acid, and kaempferol acted as a competitive TPO inhibitors, while apigenin demonstrated an uncompetitive mode of inhibitory action. Ethanol extracts from all plants acted as competitive TPO inhibitors, while, after in vitro digestion, TPO activation was found especially in the case of mustard (24%) and cumin (19.85%). Most importantly, TPO activators acted synergistically. The TPO effectors acted as LOX inhibitors. The most effective were potentially bioaccessible compounds from green tea and green coffee (IC50 = 29.73 mg DW/mL and 30.43 mg DW/mL, respectively). The highest free radical scavenging ability was determined for catechin and sinapinic acid (IC50 = 78.37 µg/mL and 84.33 µg/mL, respectively) and potentially bioaccessible compounds from mustard (0.42 mg DW/mL) and green coffee (0.87 mg DW/mL). Green coffee, green tea, cumin, and mustard contain potentially bioaccessible TPO activators that also act as effective LOX inhibitors, which indicate their potentially health-promoting effects for people suffering from Hashimoto’s disease.

2018 ◽  
Vol 4 (3) ◽  
pp. 114-119
Author(s):  
Quang Ung Le ◽  
◽  
Horng Liang Lay ◽  
Ming Chang Wu ◽  
◽  
...  

Agrimonia pilosa Ledeb (AL) has received considerable attention as a herbal medicine for its applications in ethnopharmacology with heath benefits. This study aimed to investigate antioxidant activities and A549 growth inhibitory capacity from its root extract (RE) and aerial parts extract (AE). The 50% ethanol extracts were used for the tests. The total polyphenol content and the antioxidant effects comprising ABTS+ and DPPH free radical scavenging activities were evaluated. Phenolic compounds in the extracts were isolated using high performance liquid chromatography (HPLC). Lactate dehydrogenase released in medium was also evaluated. Total phenolic and flavonoid content, and in vitro antioxidant potential of the RE were higher (p<0.01) than that of the AE. Two individual phenolic compounds consisting of 4-hydroxybenzoic acid and p-coumaric acid were firstly identified in both by HPLC. The RE exhibited higher A549 inhibitory capacity compared to the AE and activated the apoptotic proteins of bcl-2, bax, bad, caspase-3 and caspase-9 in A549. In conclusion, the AL extracts were more effective in antioxidant and A549 cells inhibitory capacity.


2018 ◽  
Vol 42 ◽  
pp. 129-136 ◽  
Author(s):  
Shuaishuai Yan ◽  
Hongjun Shao ◽  
Zhihao Zhou ◽  
Qi Wang ◽  
Luhua Zhao ◽  
...  
Keyword(s):  

2013 ◽  
Vol 53 (2) ◽  
pp. 793-800 ◽  
Author(s):  
Yanlan Xie ◽  
Agnieszka Kosińska ◽  
Hairong Xu ◽  
Wilfried Andlauer

Author(s):  
Yamina Ben Miri ◽  
Aldjia Taoudiat ◽  
Mohamed Mahdid

The aim of the study was to determine the phenolic and flavonoid content of essential oils (EOs), chloroform and ethanolic extracts of 12 Algerian Thymus species and evaluate their antioxidant and antifungal activities. EOs (1.73 ± 0.30–15.00 ± 1.24 μg/mg), chloroform extracts (33.8 ± 2.42–160.93 ± 3.88 μg/mg) and ethanol extracts (27.01 ± 3.56 –148.46 ± 4.40 μg/mg) showed considerable phenolic content. Flavonoids values of chloroform extracts ranged between 3.39± 0.17 and 20.27 ± 0.29 μg/ml while ethanolic extracts values ranged between 2.81 ± 0.11 and 26.64 ± 0.18 μg/mg. Results of DPPH showed that EOs, chloroform and ethanolic extracts exhibited strong radical scavenging activity (IC50 = 21.75 ± 6.54–338.22 ± 2.99 μg/ml, 22.91 ± 5.59–90.93 ± 1.36 μg/ml, and 33.51 ± 5.72–103.80 ± 4.54 μg/ml, respectively). Inhibition of β-carotene bleaching was potentially performed by all EOs (66.48 ± 2.41–94.06 ± 2.68 %), chloroform extracts (68.98± 1.58–95.30± 1.99%), and ethanolic extracts (62.15 ± 2.51–92.36± 1.15%). The antifungal activity of EOs and extracts was tested using the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). The EOs (0.1 ± 0.00 mg/ mL – 1.06 ± 0.46 mg/mL), chloroform (0.1 ± 0.00 mg/ mL –1.06 ± 0.46 mg/mL) and ethanol (0.1 ± 0.00 mg /mL–1.6 ± 0.00 mg/mL) showed remarkable antifungal activity against mycotoxigenic Aspergillus genera. The MFC of EOs (1.0 ± 0.34 mg/mL and > 4.8 mg/mL) , chloroform (0.26 ± 0.11 mg/mL and > 1.6 mg/mL) and ethanol (0.2 ± 0.00 mg/mL and > 1.6 mg/mL) were fungicidal in nature higher than MICs. The findings of the study indicated that Thymus spp. EOs and extracts could be used as natural alternatives for food industry.


2013 ◽  
Vol 8 (6) ◽  
pp. 1934578X1300800
Author(s):  
Junho Seo ◽  
Jiyeon Kim ◽  
Geon Go ◽  
Jung-Suk Sung ◽  
Kwang-Geun Lee

The antibacterial activities of the ethanol extracts of 35 medicinal plants were screened against Escherichia coli, Bacillus cereus, and Staphylococcus aureus by following standard antimicrobial susceptibility testing procedures. The ethanol extracts of Coptis chinensis and Glycyrrhiza uralensis showed antibacterial activity against all three test bacterial species. The screened extracts were also tested for their antioxidant activities using the DPPH free radical scavenging activity assay, and for their cytotoxic and antioxidant activity in vitro using an assessment of cell viability on mouse embryonic fibroblast cells. The ethanol extracts of both C. chinensis and G. uralensis showed good radical scavenging antioxidant properties and attenuated the rate of cell death caused by oxidative damage. Our results showed that C. chinensis and G. uralensis are promising sources of natural products with good antibacterial and antioxidant activities.


Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4114
Author(s):  
Jozef Fejér ◽  
Ivan Kron ◽  
Daniela Gruľová ◽  
Adriana Eliašová

In the present study, in vitro hydroxyl radical scavenging activities, total phenols and terpene contents in 70% ethanol extracts were evaluated. Samples of crushed (CB) and non-crushed ripe juniper berries (NCB) collected at five localities in North-East Slovakia during the years 2012–2014 were compared. Standard or modified methods for determining phytochemical and antioxidant activity were used together with a novel method for the evaluation of the results after the correction of the measured values per gram of dry matter (DM). Statistically significantly higher DM contents (average values for three years) were found in the CB extracts (ranging from 18.86 to 21.91 mg/mL) in comparison to those for NCB (ranging from 2.59 to 9.90 mg/mL). Depending on the localities and years, the hydroxyl radical scavenging activity ranged from 15.52 to 32.85% for NCB and from 65.59 to 88.12% for CB, respectively. The contents of total phenols ranged from 43.75 to 246.75 mg gallic acid equivalents (GAE)/L (NCB) and from 151.84 to 278.19 mg GAE/L (CB), respectively. However, the higher content of total phenols per gram of DM was found in the NCB extracts (8.49–42.23 mg GAE/g DM) and then in CB (6.87–18.77 GAE/g DM). The results obtained in this study showed a higher efficiency for extraction from juniper berries in 70% ethanol if the pericarp was disrupted in comparison to that achieved with the maceration of intact berries.


Author(s):  
Anindita Banerjee ◽  
Bithin Maji ◽  
Sandip Mukherjee ◽  
Kausik Chaudhuri ◽  
Tapan Seal

Objective: The aim of the present study was to evaluate the alpha (α)-amylase and alpha (α)-glucosidase inhibitory activities and in vitro antioxidant activities of the 80 % aqueous ethanol extracts of Tinosporasinensis Lour (Merr.).Methods: The 80% aq. ethanol extract of the plant was prepared. The plant extract was examined for its antioxidant activity by using free radical 1,1-diphenyl-2-picryl hydrazyl (DPPH) scavenging method, ABTS radical scavenging ability, reducing power capacity, estimation of total phenolic content, flavonoid content and flavonol content. Different concentrations (2, 4, 8,10and 15 μg/ml) of the extract was subjected to α-amylase inhibitory and α-glucosidase inhibitory activities and IC50were calculated.Results: The study revealed that the different concentrations of the plant extract possessed a very good amount of total phenolics, flavonoid and flavonol and exhibited potent radical scavenging activity using DPPH and ABTS as a substrate. The ethanol extracts exhibited significant α-amylase and α-glucosidase inhibitory activities with an IC50 value1.093µg and 1.04µg dry extract respectively and well compared with standard acarbose drug.Conclusion: Thus, it could be concluded that due to the presence of antioxidant components the plant extracts could be used for the treatment of hyperglycemia, diabetes and the related condition of oxidative stress. This knowledge will be useful in finding more potent components from the natural resources for the clinical development of antidiabetic therapeutics.


2021 ◽  
Vol 26 ◽  
pp. 2515690X2110366
Author(s):  
Hope Onohuean ◽  
Abdullateef I. Alagbonsi ◽  
Ibe M. Usman ◽  
Keneth Iceland Kasozi ◽  
Athanasios Alexiou ◽  
...  

Background. Annona muricata and Khaya grandifoliola are ethnomedicinally used for the treatment of malaria and have been experimentally shown to have an anti-plasmodial effect, but the mechanisms involved are not fully understood. This study investigated the effect of the ethanol extracts of their leaves on parasitemia, radical scavenging and cytokines in Plasmodium berghei ANKA-infected BALB/c mice. Methods. BALB/c mice were infected with P. berghei and treated with chloroquine, A. muricata or K. grandifoliola extract for 4 days. The percentage of parasitemia and the level of cytokine expression were determined after treatment. Trace element, phytochemical and nitric oxide (NO) scavenging activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging properties assays were done to study the antioxidant effects of AN and KG in vitro. Results. P. berghei consistently increased parasitemia in BALB/c mice. The tested doses (100-, 200-, and 400 mg/kg) of A. muricata and K. grandifoliola attenuated the P. berghei-induced elevation of parasitemia and cytokines (TNF-α, IL-5, and IL-6) in vivo during the experimental period, though not as much as chloroquine. Moreover, both extracts scavenged the DPPH and NO radicals, though A. muricata had more anti-oxidant effect than K. grandifoliola in-vitro. Conclusion. The ethanol extracts of A. muricata and K. grandifoliola reduce parasitemia in P. berghei-treated mice BALB/c by scavenging free radicals and reducing cytokines, though the extracts were not as effective as chloroquine.


Antioxidants ◽  
2019 ◽  
Vol 8 (8) ◽  
pp. 278 ◽  
Author(s):  
Chan-Su Rha ◽  
Hyun Woo Jeong ◽  
Saitbyul Park ◽  
Siyoung Lee ◽  
Young Sung Jung ◽  
...  

(1) Background: Extensive research has focused on flavan-3-ols, but information about the bioactivities of green tea flavonols is limited. (2) Methods: In this study, we investigated the antioxidative, anti-inflammatory, and anticancer effects of flavonol glycosides and aglycones from green tea using in vitro cell models. The fractions rich in flavonol glycoside (FLG) and flavonol aglycone (FLA) were obtained from green tea extract after treatment with tannase and cellulase, respectively. (3) Results: FLG and FLA contained 16 and 13 derivatives, respectively, including apigenin, kaempferol, myricetin, and quercetin, determined by mass spectrometry. FLA exhibited higher radical-scavenging activity than that of FLG. FLG and FLA attenuated the levels of intracellular oxidative stress in neuron-like PC-12 cells. The treatment of RAW 264.7 murine macrophages with FLG and FLA significantly reduced the mRNA expression of inflammation-related genes in a dose-dependent manner. Furthermore, FLG and FLA treatments decreased the viability of the colon adenoma cell line DLD-1 and breast cancer cell line E0771. Moreover, the treatment with FLG or FLA combined with paclitaxel had synergistic anticancer effects on the DLD-1 cell line. (4) Conclusions: Flavonols from green tea exerted beneficial effects on health and may be superior to flavan-3-ols.


2014 ◽  
Vol 32 (No. 2) ◽  
pp. 177-181 ◽  
Author(s):  
Y.-H. Wong ◽  
Ch.-P. Tan ◽  
K. Long ◽  
K.-L. Nyam

We investigate the biostability of phenolic acids from a kenaf (Hibiscus cannabinus L.) seed extract using an in vitro model simulating the physicochemical (pH, temperature and bile salts) and biological (gastric and pancreatic enzymes) gastrointestinal conditions. Some of the antioxidants in the kenaf seed extract were not relatively stable in the intestinal phase of the gastrointestinal tracts. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity and total phenolic content (TPC) assays displayed similar trends as the biostability of phenolic acids, which decreased during the digestion process. The overall percentage loss of selected phenolic acids was 8.4&ndash;49.4% in the intestinal phase. For the overall in vitro digestion system, significant correlations between phenolic acids, total phenolic content (TPC) and antioxidant activity (DPPH) were obtained in all digestion phases with the exception of the gastric phase. &nbsp;


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