Protective effect of white tea extract against acute oxidative injury caused by adriamycin in different tissues

Supplementation with Standardized Green/Black or White Tea Extracts Attenuates Hypertension and Ischemia-Reperfusion-Induced Myocardial Damage in Mice Infused with Angiotensin II

Arterial hypertension has a high prevalence in the population and is considered both a cardiovascular disease and an important risk factor for the development of other cardiovascular diseases. Tea consumption shows antihypertensive effects due to its composition in terms of bioactive substances such as flavan-3-ols and xanthines. The aim of this study was to assess the possible beneficial effects of two tea extracts, one of white tea (ADM® White Tea; WTE) and another one composed of a mixture of black tea and green tea (ADM® Tea Complex; CTE), on the cardiovascular alterations induced by angiotensin II (AngII) infusion in mice. For this purpose, four groups of C57BL/6J male mice were used: (1) mice fed on a standard diet for 8 weeks and infused with saline for the last 4 weeks (controls); (2) mice fed on a standard diet for 8 weeks and infused with AngII for the last 4 weeks (AngII); (3) mice fed on a standard diet supplemented with 1.6% WTE and infused with AngII for the last 4 weeks (AngII + WTE); (4) mice fed on a standard diet supplemented with 1.6% TC and infused with AngII for the last 4 weeks (AngII + CTE). Both tea extracts exerted anti-inflammatory and antioxidant effects in arterial tissue and reduced AngII-induced endothelial dysfunction in aorta segments. Moreover, supplementation with WTE or CTE reduced the Ang-II-induced overexpression of AT1R and increased AngII-induced downregulation of AT2R in arterial tissue. However, only supplementation with CTE significantly increased the circulating levels of angiotensin 1-7 and reduced systolic blood pressure. In the heart, supplementation with both tea extracts attenuated AngII-induced cardiac hypertrophy and reduced ischemia-reperfusion-induced oxidative stress and apoptosis in myocardial tissue. In conclusion, supplementation with WTE or CTE attenuates AngII-induced cardiovascular damage through their anti-inflammatory, antioxidant, and antiapoptotic effects. In addition, supplementation with CTE also exerts antihypertensive effects, and so it may constitute an avenue through which to support cardiovascular health.

Clinical and Biochemical Efficacies of Green and White Tea Extract Mouthwashes in the Management of Plaque-Induced Gingivitis

OBJECTIVE

In this clinical study, chlorhexidine gluconate (CHX) was chosen as the positive control group, and the clinical and biochemical efficacy of mouthwashes with green tea, white tea and essential oil (EO) as the active ingredients were aimed to be examined comprehensively.

METHODS

A total of 112 participants with gingivitis were randomly assigned to four different groups and different mouthwashes were used for 4 weeks: CHX-MW group (as a positive control group), EO-MW group, GT-MW group and WT-MW group. The effects of the mouthwashes on plaque, inflammation and dental staining were evaluated by indexed scores at the beginning and 4th week. Markers related to gingival inflammation and oxidative stress were evaluated on samples from the gingival crevicular fluid.

RESULTS

In the 4th week, significant improvements in clinical parameters were found in all groups (p < 0.05) with the more pronounced improvement in the CHX-MW group (p < 0.05). However, only the CHX caused a significant discolouration of both teeth and tongue (p < 0.05). The levels of IL-1β and MMP-8 were found to be lower in all groups compared to the first measurements (p < 0.05). Furthermore, the antioxidant effect of EO mouthwash was found significantly low compared to the other three mouthwashes (p < 0.05).

CONCLUSION

Green and white tea extracts provided clinical benefits in the short term (1 month) with no statistical difference from each other and mouthwash with EO as the active ingredient while they provided a lower clinical benefit compared to CHX. Products with tea as the active ingredient may be an alternative to EO mouthwash for short-term and long-term use.

Tea's anti-obesity properties, cardiometabolic health-promoting potentials, bioactive compounds, and adverse effects: A review focusing on white and green teas

Tea is one of the most commonly consumed beverages in the world. Morocco, Japan, and China have consumed green tea for centuries. White tea, which is a variety of green teas, is very popular in China and is highly revered for its taste. Presently, both teas are consumed in other countries around the world, even as functional ingredients, and novel research is constantly being conducted in these areas. We provide an update on the health benefits of white and green teas in this review, based on recent research done to present. After a general introduction, we focused on tea's anti-obesity and human health-promoting potential, adverse effects, and new approaches to tea and its bioactive compounds. It has been found that the health benefits of tea are due to its bioactive components, mainly phenolic compounds. Of these, catechins are the most abundant. This beverage (or its extracts) has potential anti-inflammatory and antioxidant properties, which could contribute to body weight control and the improvement of several chronic diseases. However, some studies have mentioned the possibility of toxic effects; therefore, reducing tea consumption is a good idea, especially during the last trimester of pregnancy. Additionally, new evidence will provide insight into the possible effects of tea on the human gut microbiota, and even on the viruses responsible for SARS-CoV-2. A beverage such as this may favor beneficial gut microbes, which may have important implications due to the influence of gut microbiota on human health.

ABTS/TAC Methodology: Main Milestones and Recent Applications

ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid) is a widely used compound for determining the total antioxidant capacity (TAC) of plant extracts, food, clinical fluids, etc. This photometric assay is based on the reduction by the presence of antioxidant compounds of a well-known metastable radical (ABTS•+) which can be formed via several different approaches and be used in many different determination methodologies such as automated photometric measures in microplates, clinical robots, valuable titrations, and previous liquid chromatographic separation. Another interesting aspect is that, in some cases, the ABTS/TAC method permits sequential hydrophilic and lipophilic antioxidant activity determinations, obtaining total antioxidant activity values through the summatory data of both types of antioxidants. In this work, we present a review of several aspects of the ABTS/TAC, highlighting the major achievements that have made this method so widely used, e.g., ABTS radical formation in hydrophilic or lipophilic reaction media, measurement strategies, automatization, and adaptation to high-throughput systems, as well as the pros and cons. Moreover, some recent examples of ABTS/TAC method applications in plant, human, and animal samples are discussed.

Catechins: Protective mechanism of antioxidant stress in atherosclerosis

Tea has long been valued for its health benefits, especially its potential to prevent and treat atherosclerosis (AS). Abnormal lipid metabolism and oxidative stress are major factors that contribute to the development of AS. Tea, which originated in China, is believed to help prevent AS. Research has shown that tea is rich in catechins, which is considered a potential source of natural antioxidants. Catechins are the most abundant antioxidants in green tea, and are considered to be the main compound responsible for tea's antioxidant activity. The antioxidant properties of catechins are largely dependent on the structure of molecules, and the number and location of hydroxyl groups or their substituents. As an exogenous antioxidant, catechins can effectively eliminate lipid peroxidation products. They can also play an antioxidant role indirectly by activating the endogenous antioxidant system by regulating enzyme activity and signaling pathways. In this review, we summarized the preventive effect of catechin in AS, and emphasized that improving the antioxidant effect and lipid metabolism disorders of catechins is the key to managing AS.

White Tea Intake Abrogates Markers of Streptozotocin-Induced Prediabetes Oxidative Stress in Rat Lungs'

Prediabetes (PrDM) is a prodromal stage of diabetes mellitus (DM) with an increasing prevalence worldwide. During DM progression, individuals gradually develop complications in various organs. However, lungs are suggested to be affected later than other organs, such as the eyes, heart or brain. In this work, we studied the effects of PrDM on male Wistar rats’ lungs and whether the regular consumption of white tea (WTEA) for 2 months contributes to the improvement of the antioxidant profile of this tissue, namely through improved activity of the first line defense antioxidant enzymes, the total antioxidant capacity and the damages caused in proteins, lipids and histone H2A. Our data shows that PrDM induced a decrease in lung superoxide dismutase and glutathione peroxidase activities and histone H2A levels and an increase in protein nitration and lipid peroxidation. Remarkably, the regular WTEA intake improved lung antioxidant enzymes activity and total antioxidant capacity and re-established the values of protein nitration, lipid peroxidation and histone H2A. Overall, this is the first time that lung is reported as a major target for PrDM. Moreover, it is also the first report showing that WTEA possesses relevant chemical properties against PrDM-induced lung dysfunction.

Combination of white tea and peppermint demonstrated synergistic antibacterial and anti-inflammatory activities

BACKGROUND

White tea, considered to be the oldest form of tea, is becoming a popular beverage for its organoleptic characteristics. Peppermint tea, used as a herbal remedy for centuries, is now also very popular throughout the world as herbal tea. What interested us was that in ancient China, peppermint was used in combination with tea as a detoxification or anti-inflammatory agent. However, there are few reports on the combined use of white tea and peppermint. Therefore, this study aims to investigate the antibacterial and anti-inflammatory activities of white tea in combination with peppermint.

RESULTS

A synergistic inhibitory effect against four bacterial strains, especially against Staphylococcus argenteus, was observed in the combination of white tea and peppermint in vitro. In addition, the combined formula demonstrated a stronger anti-inflammatory effect in vivo than either of the two used alone, which was associated with the decrease of the pro-inflammatory cytokines of interleukin-6 (IL-6), interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). In a further mechanism study, it was found that white tea and peppermint inhibited the phosphorylation of p-IκB-α and mitogen-activated protein kinase (MAPK) at different degrees. While the enhanced anti-inflammatory effect of the combined formula was associated with the combination of NF-κB down-regulation and p-MAPK inhibition.

CONCLUSION

In our study, it was for the first time shown that when white tea was combined with peppermint, the antibacterial and anti-inflammatory effects were enhanced. The results suggested an effective application of white tea in combination with peppermint as a potential antibacterial and anti-inflammatory functional food. © 2020 Society of Chemical Industry.

Dietary Ginsenoside T19 Supplementation Regulates Glucose and Lipid Metabolism via AMPK and PI3K Pathways and Its Effect on Intestinal Microbiota

Ginseng, as a functional food, is widely used worldwide because of its multifarious benefits. Studies have verified that 25-hydroxyl-protopanaxatriol (T19) is a new ginsenoside from ginseng, which had an important inhibitory effect on α-glucosidase and protein tyrosine phosphatase 1B in vitro. This study aims to assess the regulation of T19 against glycolipid metabolism by insulin-resistant HepG2 cells and diabetes mice induced with high-fat diet combined with streptozotocin (STZ). T19 effectively lowered the levels of blood glucose and lipid, alleviated insulin resistance, and improved histological pathology of liver and pancreas. Further study demonstrated that regulation of AMP-activated protein kinase- and phosphoinositide-3-kinase-signaling pathways was involved in the potential mechanism of T19 efficiency. Simultaneously, high-throughput sequencing of 16S rDNA revealed that T19 remarkably ameliorated the high-fat diet/STZ-induced disorders of intestinal microbiota by decreasing the value of Firmicutes/Bacteroidetes, and remarkably raised the relative abundance of the Lachnospiraceae family, which are the beneficial bacteria that can regulate glucose and lipid metabolism. The results may provide clues for further understanding the mechanism of T19 in regulating glycolipid metabolism, and may provide a scientific basis for ginseng as a potential dietary food to prevent metabolic diseases.

Hepatoprotective effect of Raspberry ketone and white tea against acrylamide-induced toxicity in rats

The current investigation was accomplished to evaluate the hepatoprotective effect of White tea and Raspberry Ketone against toxicity induced by acrylamide in rats. Sixty adult male rats were divided randomly into group (I) control; group (II) rats received RK with dose (6 mg/kg/day); Group III: rats received 5 ml of WT extract/kg/day; Group IV rats received AA (5 mg/kg/day); Group V: rats administrated with both AA (5 mg/kg/day) and RK (6 mg/kg/day) and Group VI: rats administrated AA (5 mg/kg/day) and 5 ml of WT extract/kg/day. The biochemical assays exhibited a significant increase in serum levels of Adiponectin, AST, ALT, ALP of the group treated with acrylamide if compared to the control group and an improvement in their levels of groups V and VI. The histopathological and immunohistochemical findings confirm the biochemical observations. In conclusion, the present investigation proved that the supplementation of WT and RK enhanced the liver histology, immunohistochemistry and biochemistry against the oxidative stress induced by acrylamide.

Jiaogulan tea (Gpostemma pentaphyllum) potentiates the antidiabetic effect of white tea via the AMPK and PI3K pathways in C57BL/6 mice

The use of plant-based beverages to interfere with the onset of diabetes may be a promising approach towards type 2 diabetes mellitus (T2DM).

Non-targeted Metabolomic Analysis Based on Ultra-High-Performance Liquid Chromatography Quadrupole Time-of-Flight Tandem Mass Spectrometry Reveals the Effects of Grafting on Non-volatile Metabolites in Fresh Tea Leaves ( Camellia sinensis L.)

To investigate the effects of grafting on non-volatile metabolites in tea, non-targeted metabolomic analyses of fresh leaves were performed on the basis of ultra-high-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF/MS). One non-grafted YingHong No. 9 and four grafted tea [grafting scion YingHong No. 9 on four different rootstocks, BaiMao No. 2 (BM2), BaiYeDanCong (BY), HeiYeShuiXian (HY), and WuLingHong (WLH)] were chosen as materials. In total, 32 differential metabolites were identified, including phenolic acids, flavan-3-ols, dimeric catechins, flavonol and flavonol/flavone glycosides, etc. Partial least squares discrimination analysis and hierarchical cluster analysis showed various effects of different rootstocks on metabolites. Thereinto, rootstocks of WLH and BY showed extremely outstanding performance in up- and downregulating these metabolites, respectively. Differential metabolites were enriched into three crucial pathways, including biosynthesis of phenylpropanoids, flavonoid biosynthesis, and flavone and flavonol biosynthesis, which might influence the quality of tea. This study provides a theoretical basis for grafting-related variations of non-volatile metabolites in fresh tea leaves.

Japanese, Mediterranean and Argentinean diets and their potential roles in neurodegenerative diseases

Environmental factors are responsible of cellular senescence and processes found in the development of cognitive disorders. The aim of this paper is to compare benefits of the Japanese, Mediterranean, and Argentinian Diet on the onset or prevention of senile dementia (SD) and Alzheimer's Disease (AD). Special focus was on the effects of specific compounds such as polyunsaturated fatty acids (PUFAs), antioxidants, and saturated and trans fatty acids. A high adherence to diets rich in PUFAs, monounsaturated fatty acids (MUFAs) and antioxidants may decrease the risk of developing neurodegenerative diseases; while the predominance of saturated and trans fatty acids possibly rises it.

Healthy properties of green and white teas: an update

Green tea has been consumed for centuries in Japan, China and Morocco.

Long-term intake of white tea prevents oxidative damage caused by adriamycin in kidney of rats

BACKGROUND

White tea infusion (Camelia sinensis) has antioxidants properties. The infusion contains polyphenols that have been proposed to induce antioxidant response element (ARE) response via nuclear factor E2-related factor 2 (NRF2). Adriamycin (ADR) has antitumour properties and oxidative effects. Oxidative stress is related to a variety of kidney diseases. Prevention of the oxidative stress through long-term intake of white tea and the study of the molecular mechanisms involved in protection could be of great interest. Rats were given distilled water, 0.015 or 0.045 g of solid white tea extract kg(-1) body weight for 12 months. Animals received an injection of ADR. In kidney, oxidative stress parameters were measured, the expressions of nuclear factor E2-related factor 2 gene (Nrf2), and detoxifying and antioxidants genes were analysed, and the activities of catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) were measured.

RESULTS

ADR administration increased oxidative parameters and decreased the antioxidant activity; significantly increased the expression of analysed genes and the activity of CAT and SOD and decreased GR activity. The highest white tea dose protected redox status and inhibited ARE response.

CONCLUSION

Long-term intake of white tea protected kidney against the oxidative stress. ADR activated the ARE response but in animals treated with the highest dose of white tea, this response was inhibited, probably for antioxidant protection. © 2015 Society of Chemical Industry.

Beneficial effects of carnosine and carnosine plus vitamin E treatments on doxorubicin-induced oxidative stress and cardiac, hepatic, and renal toxicity in rats

OBJECTIVE

Oxidative stress plays an important role in doxorubicin (DOX)-induced toxicity. Carnosine (CAR) is a dipeptide with antioxidant properties. The aim of this study was to evaluate the decreasing or preventive effect of CAR alone or combination with vitamin E (CAR + Vit E) on DOX-induced toxicity in heart, liver, and brain of rats.

METHODS

Rats were treated with CAR (250 mg kg(-1) day(-1); intraperitoneally (i.p.)) or CAR + Vit E (equals 200 mg kg(-1) α-tocopherol; once every 3 days; intramuscularly) for 12 consecutive days. On the 8th day of treatment, rats were injected with a single dose of DOX (30 mg kg(-1), i.p.). Serum cardiac troponin I (cTnI), urea, and creatinine levels; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities; and oxidative stress parameters in tissues were measured. We also determined thiobarbituric acid reactive substances, diene conjugate, protein carbonyl (PC), and glutathione levels and antioxidant enzyme activities.

RESULTS

DOX resulted in increased serum cTnI, ALT, AST, urea, and creatinine levels and increased lipid peroxide and PC levels in tissues. CAR or CAR + Vit E treatments led to decreases in serum cTnI levels and ALT and AST activities. These treatments reduced prooxidant status and ameloriated histopathologic findings in the examined tissues.

CONCLUSION

Our results may indicate that CAR alone, especially in combination with Vit E, protect against DOX-induced toxicity in heart, liver, and kidney tissues of rats. This was evidenced by improved cardiac, hepatic, and renal markers and restoration of the prooxidant state and amelioration of histopathologic changes.

Molecular mechanisms by which white tea prevents oxidative stress

The flavonoid content of tea (Camellia sinensis) has beneficial properties in the prevention of diseases. However, the mechanisms by which white tea can protect against oxidative stress remain unclear. To shed light on this issue, rats were given distilled water (controls), 0.15 mg/day (dose 1) or 0.45 mg/day (dose 2) of solid tea extract/kg body weight for 12 months. All the animals received an injection of adriamycin (ADR; 10 mg/kg body weight), except half of the control group, which were given an injection of saline solution. The expression of the nuclear factor, E2-related factor 2 (Nrf2), NAD(P)H:quinone oxidoreductase 1 (Nqo1), glutathione S-transferase (Gst), haem oxygenase-1 (Ho1), catalase (Cat), superoxide dismutase (Sod) and glutathione reductase (Gr) in liver was analysed by real-time PCR, and the activity of catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) was measured spectrophotometrically. ADR significantly increased the expression of Nrf2, Gst, Nqo1, Ho1, Cat, Sod and Gr with respect to the control levels and also increased the activity of CAT, SOD and GR. The intake of white tea increased in a higher degree the expression of Nrf2, Gst, Nqo1 and Ho1 in the tea + ADR group compared with the control group and C + ADR group. In addition, tea + ADR groups decreased the expression and activity of CAT, SOD and GR in a dose-dependent manner.

Radical scavenging of white tea and its flavonoid constituents by electron paramagnetic resonance (EPR) spectroscopy

White tea (WT) presents high levels of catechins, which are known to reduce oxidative stress. WT is the least processed tea, unfermented and prepared only from very young tea leaves. The subject of this paper is the use of the spin trap method and electron paramagnetic resonance (EPR) spectroscopy as the analytical tool to measure, for the first time, the radical scavenging activity of WT and its major catechin components, epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC), and epigallocatechin-3-gallate (EGCG), against the methoxy radical, using ferulic acid as antioxidant pattern. The antioxidant activity has been measured by the decrease of the intensity of the spectral bands of the adduct DMPO-OCH3 in the EPR with the amount of antioxidant in the reactive mixture. Tea leaves and buds were extracted with waterless methanol. It has been proved that tea compounds with more antiradical activity against methoxy radical are those with the gallate group, EGCG and ECG.

Profile and antioxidant activity of phenolic extracts from 10 crabapples (Malus wild species)

Phenolic products are highly demanded by the food and cosmetics industries and consumers due to their high antioxidant activities. To evaluate the potential of crabapples (Malus wild species) in preparing phenolic extracts, fruits of 10 crabapples grown in China were separately extracted with 80% (v/v) ethanol and ethyl acetate and the phenolic profiles, polyphenol (PC) and flavonoid contents (FC), and antioxidant activities of the extracts were analyzed. Chlorogenic acid, (-)-epicatechin, rutin, hyperin, and phlorizin appeared as the major phenolic compounds in all phenolic extracts. Ethanol extracts had PC of 302.83-1265.94 mg GAE/100g and FC of 352.45-2351.74 mg RE/100g, being 4.17 and 4.49 times those obtained in ethyl acetate extracts and much higher than those previously reported in apples. Malus wild species appeared as rich sources of phenolic compounds with high antioxidant activity, especially when high chlorogenic acid and rutin contents are emphasized.

Decrease in the antioxidant capacity in beverages containing tea extracts during storage

The aim of this work was to determine antioxidant capacity of beverages containing black, white, and green tea extracts using the photochemiluminescence method, and to monitor its changes based on the storage temperature and time. Samples were stored at two different temperatures (refrigerated at 4°C and laboratory temperature 22°C), analyzed after opening of the original package, and consequently after 4 and 7 days. Results of the antioxidant capacity are expressed as the standard equivalents, that is, ascorbic acid in mmol/L. The highest mean value of the antioxidant capacity was found after opening of the original package in fruit-juice-enriched samples and totaled 9.793 mmol/L. This group revealed significant dependence (P < 0.05) not only on the storage time, but also temperature. In samples without added fruit juices containing preservatives the value was 0.428 mmol/L. This group showed significant dependence (P < 0.05) on the decrease of antioxidant capacity only when based on the storage time. Samples without fruit juices or preservatives showed significant decrease in the antioxidant capacity (P < 0.05) after 4 days of storage based on the storage time. The dependence on temperature was revealed only after 7 days of storage.