Effect Of Green Tea Extract Research Articles

Green tea extracts for the prevention of metachronous colorectal polyps among patients who underwent endoscopic removal of colorectal adenomas: A randomized clinical trial

To determine the preventive effect of green tea extract (GTE) supplements on metachronous colorectal adenoma and cancer in the Korean population. One hundred seventy-six subjects (88 per each group) who had undergone complete removal of colorectal adenomas by endoscopic polypectomy were enrolled. They were randomized into 2 groups: supplementation group (0.9g GTE per day for 12 months) or control group without GTE supplementation. The 72-h recall method was used to collect data on food items consumed by participants at baseline and the 1-year follow-up during the past 48h. Follow-up colonoscopy was conducted 12 months later in 143 patients (71 in control group and 72 in the GTE group). Of the 143 patients completed in the study, the incidences of metachronous adenomas at the end-point colonoscopy were 42.3% (30 of 71) in control group and 23.6% (17 of 72) in GTE group (relative risk [RR], 0.56; 95% confidence interval [CI], 0.34-0.92). The number of relapsed adenoma was also decreased in the GTE group than in the control group (0.7±1.1 vs. 0.3±0.6, p=0.010). However, there were no significant differences between the 2 groups in terms of body mass index, dietary intakes, serum lipid profiles, fasting serum glucose, and serum C-reactive protein levels (all p>0.05). This study of GTE supplement suggests a favorable outcome for the chemoprevention of metachronous colorectal adenomas in Korean patients(ClinicalTrials.gov number, NCT02321969).

Green tea extract induces genes related to browning of white adipose tissue and limits weight-gain in high energy diet-fed rat

ABSTRACTBackground: A wealth of research has reported on the anti-obesity effects of green tea extract (GTE). Although browning of white adipose tissue (WAT) has been reported to attenuate obesity, no study has disclosed the effects of GTE on browning in Sprague Dawley rats.Objectives: The aims of the study were to investigate the effects of GTE on anti-obesity and browning, and their underlying mechanisms.Methods: Four groups of rats (n=10/group) were used including a normal diet with vehicle treatment, and a high-energy diet (HED) with vehicle or GTE by oral gavage at 77.5 or 155 mg/kg/day for 8 weeks. Body weight, fat accumulation, and serum biochemical parameters were used to evaluate obesity. The gene expressions were analyzed using RT-qPCR and western blotting.Results: GTE modulated HED-induced body weight, fat accumulation, and serum levels of triacylglycerol, total cholesterol, low-density lipoprotein, free fatty acids, aspartate aminotransferase, and alanine aminotransferase. Moreover, GTE enhanced the serum high-density lipoprotein. Most importantly, the biomarkers of beige adipose tissue were up-regulated in WAT in GTE-given groups. GTE induced genes involved in different pathways of browning, and reduced transducin-like enhancer protein-3 in WAT.Conclusion: Our results suggest that GTE may improve obesity through inducing browning in HED-fed rats.Abbreviations: ALT: Alanine transaminase; AST: Aspartate transaminase; BAT: Brown adipose tissue; BMP-7: Bone morphogenetic protein-7; BW: Body weight; CIDEA: Cell death activator; CPT-1: Carnitine palmitoyltransferase-1; EFP: Epididymal fat pad; FFA: Free fatty acid; FGF-21: Fibroblast growth factor-21; GTE: Green tea extract; HDL: High-density lipoprotein; HED: high-energy diet; LDL: Low-density lipoprotein; MFP: Mesenteric fat pad; PGC-1α: Activates PPAR-γ coactivator-1; PPAR-γ: Peroxisome proliferator-activated receptor-γ; PRDM-16: PR domain containing 16; RFP: Renal fat pad; SD: Sprague Dawley; TC: Total cholesterol; TG: Triacylglycerol; TLE-3: Transducin-like enhancer protein-3: UCP-1: Uncoupling protein-1; WAT: White adipose tissue.

The Effect of Green Tea Extract on Oxidative Stress and Spatial Learning in Streptozotocin-diabetic Rats.

group. This study demonstrated the effectiveness of TGTE on spatial impairment and oxidative stress induced in diabetes mellitus.

Therapeutic benefits of green tea extract on various parameters in non-alcoholic fatty liver disease patients.

Background and Objective:NAFLD affecting up to 30% of the population globally. Drug treatment options are limited with disappointing results. The dietary supplementation in the form of green tea is another option. Our objective was toinvestigate the effect of Green tea extract (GTE) supplementation on various parameters innon-alcoholicfatty liver disease (NAFLD) patients.Methods:This study was conducted Dept. of Medicineof Sheikh Zayed Medical College/Hospital, Rahim Yar Khan from 15 April 2016 to 15 July 2016. Eighty overweight, non diabeticand dyslipidemic patients of NAFLD, diagnosed on the basis of ultrasound and aminotransferases level were randomized for treatmentwith capsule GTE500mg (n=40)and capsule placebo (n=40) twice a day for twelve weeks. Anthropometric parameters, liver enzymes, inflammatory markers and liver ultrasound imaging were estimated by SPSS-16 pre and post treatment.Results:As compared to placebo, GTE caused a significant improvement in body weight (29.5±3.8 to 27.2±3.2 kg/m2 p=0.03), BMI (86±10.5 to 80±12.4 kg p=0.026), HOMA-IR(4.32±2.25 to 3.16± 1.6 p=0.0081) lipid profile (i.e. TC: L242.5±20.5 to 215.4±18.6 mg/dl p=0.005; TG: 175±22.6 to145±18 mg/dlp=0.003; LDL-C:155±12.5 to 140±16.7 mg/dl p=0.011; HDL-C: 36.8±6.7 to46.4±5.8 mg/dl p =0.001, Aminotransferases (i.e. ALT: 70.4±15.8to52.8±12.2 IU/L p=0.04; AST: 65.8±12.4 to 44.3± 8.5U/L p =0.002) and Inflammatory markers (hs-CRP: 3.14±0.58 to 2.18±0.32 p =0.023 Adiponectin: 8.46±1.02 to 10.55±3.42μg/ml p =0.003)GTE also caused a 67.5% regression of fatty liver changes on ultrasound as compared to placebo which is 25%only.Conclusion:GTEtherapy resulted in significant improvement in metabolic, chemical, inflammatory and radiological parameters of non-alcoholic fatty liver disease patients who were non-diabetic anddyslipidemic.

Effects of Green Tea Extract on Sperm Quality, Reactive Oxygen Species and Lipid Peroxidation in Long-term Liquid Preservation of Boar Spermatozoa

During storage, boar spermatozoa undergo several changes including diminished motility and viability and accumulated reactive oxygen species (ROS). In this study, we investigated the effects of green tea extract (GTE) supplementation in the Sui Dil extender on the sperm motility, viability, ROS and lipid peroxidation (LPO) of longterm preserved boar semen at 17℃. A total number of eight boars were used for this experiment. Pooled ejaculates were diluted to 20 × 10 6 sperm/ml in the Sui Dil extender containing 0 (control), 1, 10, 100 or 500 mg/l GTE and were preserved at 17℃ for 24, 72, 120 and 168 h, respectively. At each storage time, sperm motility and viability were estimated by microscopic examination and the fluorescent double stain Fertilight ® , respectively. Sperm ROS level and LPO were assessed using the 2’, 7’-dichlorodihydrofluorescein diacetate (H₂DCFDA)/propidium iodide (PI) and C11-BODIPY581/591/PI with flow cytometry, respectively. Compared to that of the 500 mg group, there were higher sperm motility and viability in the 1, 10 and 100 mg GTE groups during the preservation from 24 to 168 h (p < 0.05). The ROS levels of the 10 and 100 mg groups during the 168 h preservation were lower than those of the 0, 1 and 500 mg groups (p < 0.05). There were no significant differences in LPO regardless of the preservation period or the GTE concentration. In conclusion, the optimal concentrations (10 and 100 mg/l) of GTE that led to lower ROS levels may be useful for liquid boar sperm preservation at 17℃ for a period of 168 h.

Green tea extract intake during lactation modified cardiac macrophage infiltration and AMP-activated protein kinase phosphorylation in weanling rats from undernourished mother during gestation and lactation.

Maternal dietary restriction is often associated with cardiovascular disease in offspring. The aim of this study was to investigate the effect of green tea extract (GTE) intake during lactation on macrophage infiltration, and activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and serine-threonine kinase Akt (Akt) in the hearts of weanlings exposed to maternal dietary protein restriction. Pregnant Wistar rats were fed control (C) or low-protein diets (LP) throughout gestation. Following delivery, the dams received a control or a GTE-containing control diet during lactation: control diet during gestation and lactation (CC), low-protein diet during gestation and lactation (LPC), low-protein diet during gestation and 0.12% GTE-containing low-protein diet during lactation (LPL), and low-protein diet during gestation and 0.24% GTE-containing low-protein diet during lactation (LPH). The female offspring were sacrificed at day 22. Biochemical parameters in the plasma, macrophage infiltration, degree of fibrosis and expression levels of AMPK and Akt were examined. The plasma insulin level increased in LPH compared with LPC. Percentage of the fibrotic areas and the number of macrophages in LPC were higher than those in CC. Conversely, the fibrotic areas and the macrophage number in LPH were smaller (21 and 56%, respectively) than those in LPC. The levels of phosphorylated AMPK in LPL and LPH, and Akt in LPH were greater than those in LPC. In conclusion, maternal protein restriction may induce macrophage infiltration and the decrease of insulin levels. However, GTE intake during lactation may suppress macrophage infiltration and restore insulin secretion function via upregulation of AMPK and insulin signaling in weanlings.

Radioprotective effect of green tea and grape seed extracts mixture on gamma irradiation induced immune suppression in male albino rats

Purpose: Green tea extract (GTE) and grape seed extract (GSE) have antioxidant and radioprotective effects. The current study aimed to investigate the radioprotective effect of GTE and GSE mixture on radiation-induced immune suppression in rats.Method: A total of 35 male albino rats were divided into five groups: group 1 (control rats). The 2nd and 3rd groups rats were exposed to a single dose of gamma radiation (5 and 10 Gy), respectively. The 4th and 5th groups of rats were gamma-irradiated with 5 and 10 Gy, respectively, then administrated by gavage with GTE and GSE mixture (100 mg: 200 mg/kg BW), respectively, for 14 consecutive days.Results: Gamma irradiation induced hematological, immunological and biochemical effects in rats. Treated rats with GTE and GSE mixture (1:2) showed an increase in concentrations of immune cells including CD4 and CD8. The level of pro-inflammatory cytokines Tumor necrosis factor-α and C-reactive protein elevated after γ-irradiation and significantly decreased by mixture administration. Moreover, groups treated with antioxidant mixture showed a significant increase in all hematological parameters and a significant decrease in cholesterol and triglyceride levels.Conclusion: GTE and GSE mixture is a good radioprotector and immune modulator compound, indicating its possible use as an adjuvant during radiotherapy.

Effects of Methanol Extract of Green Tea on Biofilm Formation of Staphylococcus aureus

Background and Objectives: The aim of this study was to investigate the effect of ethanol extract of green tea on biofilm formation of Staphylococcus aureus. Methods: Staphylococcus aureus samples were obtained from hospital sources and plant extracts; green tea was made using the rotary. The minimum inhibitory concentration was determined using the microdilution method. Inhibition of biofilm formation was determined by using a microplate. Results: The results of this study showed that the greatest resistance was to the antibiotics penicillin (88.2%) and erythromycin (82.4%) and the least resistance to the antibiotic Amikacin (76/11%), respectively. The results of the effect of green tea extract showed the lowest inhibitory concentration (MIC) is equal to 0.3 milligrams per milliliter, which is a strain on the inhibitory concentration, and the highest concentration (MBC) MBC resistant Staphylococcus aureus equal to 20 milligrams per milliliter, which is controlled unidirectional. The results of green tea extract effects on biofilm showed that with increasing concentrations of less biofilm formation the biofilm formation has been much lower concentration of the extract. Conclusions: The results of this study indicate good effects of green tea extract to inhibit biofilm formation of Staphylococcus aureus, which can be used to treat infections caused by these bacteria’s.

Effects of Methanol Extract of Green Tea on Biofilm Formation of Staphylococcus aureus

Background and Objectives: The aim of this study was to investigate the effect of ethanol extract of green tea on biofilm formation of Staphylococcus aureus. Methods: Staphylococcus aureus samples were obtained from hospital sources and plant extracts; green tea was made using the rotary. The minimum inhibitory concentration was determined using the microdilution method. Inhibition of biofilm formation was determined by using a microplate. Results: The results of this study showed that the greatest resistance was to the antibiotics penicillin (88.2%) and erythromycin (82.4%) and the least resistance to the antibiotic Amikacin (76/11%), respectively. The results of the effect of green tea extract showed the lowest inhibitory concentration (MIC) is equal to 0.3 milligrams per milliliter, which is a strain on the inhibitory concentration, and the highest concentration (MBC) MBC resistant Staphylococcus aureus equal to 20 milligrams per milliliter, which is controlled unidirectional. The results of green tea extract effects on biofilm showed that with increasing concentrations of less biofilm formation the biofilm formation has been much lower concentration of the extract. Conclusions: The results of this study indicate good effects of green tea extract to inhibit biofilm formation of Staphylococcus aureus, which can be used to treat infections caused by these bacteria’s.

Ameliorating effects of green tea extract on cadmium induced reproductive injury in male Wistar rats with respect to androgen receptors and caspase- 3

Cadmium is one of the potent environmental endocrine disruptors that has adverse effects on male fertility. This study was conducted to investigate the protective role of green tea extract (GTE) on cadmium chloride (CdCl2) induced reproductive toxicities in male Wistar rats. Thirty-six male Wistar rats were divided to 4 groups, each one contained 9 rats. Control group, they were gavaged distilled water, meanwhile the treated groups gavaged CdCl2 (3mg/kg), GTE (70mg/kg) and CdCl2+GTE (3mg/kg and 70mg/kg) for 63days. In GTE+ CdCl2 treated rats, the final body weight, relative testicular weight, epididymal weight, seminal and prostate glands weights were significantly (P<0.05) increased compared to CdCl2 intoxicated rats. Sperm cell concentration was significantly (P<0.05) increased in CdCl2+GTE group, while sperm morphological abnormalities were significantly (P<0.05) decreased than CdCl2 group. The levels of superoxide dismutase (SOD) and reduced glutathione (GSH) were elevated significantly (P<0.05) in CdCl2+GTE group, meanwhile catalase activity was significantly (P<0.05) declined than CdCl2 group. Hypercholesterolemia was observed in CdCl2 group than control one while GTE+CdCl2 group revealed significant (P<0.05) reduction in cholesterol level than CdCl2 treated group. Testicular androgen receptors and caspase-3 protein expression showed marked reduction and increase (P<0.05) in CdCl2 group than control, respectively. Treatment with GTE with CdCl2 significantly (P<0.05) increased androgen receptors, while decreased caspase-3 protein than CdCl2 group. In conclusion, GTE exhibited protective effect on testes by inhibiting CdCl2 induced oxidative damage and cellular apoptosis.

Pengaruh ekstrak teh hijau (Camellia sinensis) terhadap kadar malondialdehid (MDA) plasma dan kekuatan genggam tangan lanjut usia

Background: Prevalence of Indonesian elderly has now reached 7%, which is considerably high. Physical performance is an important health status indicator in elderly. Declining of physical performance such as hand grip strength in elderly is related to oxidative stress. Furthermore, oxidative stress plays an important role on the decreasing of skeletal muscle function. Plasma malondialdehyde (MDA) is a lipid peroxidation residue that is often used as an oxidative stress biomarker. Meanwhile, tea is the most widely drunk beverage after water. Green tea contains antioxidants that can reduce the damages caused by oxidative stress. Objective: To assess the effect of green tea extract (GTE) on plasma malondialdehyde level and hand grip strength of elderly.Method: This was a double-blind experimental with pre-post test and control group. Fifty-seven elderly people from Balai Pelayanan Social Tresna Wredha (BPSTW) Abiyoso and Budi Luhur who met inclusion and exclusion criteria were divided into 2 groups. During 30 days, the first group was given 2 capsules of GTE a day (±168 mg catechin and 95 mg Epigallocatechin gallate (EGCG) and the second group was given a placebo. MDA was measured by thiobarbituric acid (TBA)method and hand grip strength was measured by handgrip hand grip dynamometer. Results: There was a significant decreasing MDA (p&lt;0,05) in the GTE group, but not in the placebo group. There was also increasing handgrip strength in the GTE group but not in the placebo group. Conclusion: Green tea extract can prevent increasing MDA and declining physical handgrip strength in elderly.

Effect of Green Tea Extract on Systemic Metabolic Homeostasis in Diet-Induced Obese Mice Determined via RNA-Seq Transcriptome Profiles.

Green tea (GT) has various health effects, including anti-obesity properties. However, the multiple molecular mechanisms of the effects have not been fully determined. The aim of this study was to elucidate the anti-obesity effects of GT via the analysis of its metabolic and transcriptional responses based on RNA-seq profiles. C57BL/6J mice were fed a normal, high-fat (60% energy as fat), or high-fat + 0.25% (w/w) GT diet for 12 weeks. The GT extract ameliorated obesity, hepatic steatosis, dyslipidemia, and insulin resistance in diet-induced obesity (DIO) mice. GT supplementation resulted in body weight gain reduction than mice fed high-fat through enhanced energy expenditure, and reduced adiposity. The transcriptome profiles of epididymal white adipose tissue (eWAT) suggested that GT augments transcriptional responses to the degradation of branched chain amino acids (BCAAs), as well as AMP-activated protein kinase (AMPK) signaling, which suggests enhanced energy homeostasis. Our findings provide some significant insights into the effects of GT for the prevention of obesity and its comorbidities. We demonstrated that the GT extract contributed to the regulation of systemic metabolic homeostasis via transcriptional responses to not only lipid and glucose metabolism, but also amino acid metabolism via BCAA degradation in the adipose tissue of DIO mice.

Green tea reduces body fat via upregulation of neprilysin.

Consumption of green tea has become increasingly popular, particularly because of claimed reduction in body weight. We recently reported that animals with pharmacological inhibition (by candoxatril) or genetic absence of the endopeptidase neprilysin (NEP) develop an obese phenotype. We now investigated the effect of green tea extract (in drinking water) on body weight and body composition and the mediating role of NEP. To elucidate the role of NEP in mediating the beneficial effects of green tea extract, 'Berlin fat mice' or NEP-deficient mice and their age- and gender-matched wild-type controls received the extract in two different doses (300 or 600 mg kg-1 body weight per day) in the drinking water. In 'Berlin fat mice', 51 days of green tea treatment did not only prevent fat accumulation (control: day 0: 30.5% fat, day 51: 33.1%; NS) but also reduced significant body fat (green tea: day 0: 27.8%, day 51: 20.9%, P<0.01) and body weight below the initial levels. Green tea reduced food intake. This was paralleled by a selective increase in peripheral (in kidney 17%, in intestine 92%), but not central NEP expression and activity, leading to downregulation of orexigens (like galanin and neuropeptide Y (NPY)) known to be physiological substrates of NEP. Consequently, in NEP-knockout mice, green tea extract failed to reduce body fat/weight. Our data generate experimental proof for the assumed effects of green tea on body weight and the key role for NEP in such process, and thus open a new avenue for the treatment of obesity.

The effect of green tea on opposing toxicity of acrylamide on kidney function

PurposeThe purpose of this paper is to investigate the effects of green tea extract on kidney function tests, in male rats that received different doses of acrylamide (AA).Design/methodology/approachAnimals were dispensed at random to one of the following treatments: group 1 served as control, whereas groups 2, 3 received seven, 14 mg/100 g B.W/day of AA, respectively, in drinking water for 15 and 30 days. Group 4 received green tea 1.5 percent concentration and groups 5, 6 received seven, 14 mg/100 g B.W/day in a mixture with green tea for 15 and 30 days.FindingsSerum urea and creatinine significantly increase with AA. However, Total protein, albumin and A/G ratio showed significant drop in all treated groups when compared with control. Supplementation of rats with antioxidant (green tea) enhanced the general health condition, reduced the severity of genotoxic effect and the alteration in blood and serum parameters produced by AA.Practical implicationsThe authors suggest that green tea may deliver a cushion for long therapeutic option against toxins-induced nephrotoxicity without damaging side effects.Originality/valueThe study uses green tea as a natural antioxidant source. Epigallocatechin-3 gallate is the most plentiful catechin preserved in green tea and a high source of flavonoids. Flavonoids are a group of phenolic products of plant metabolism with high antioxidant properties to reduce nephrotoxicity without side effects.

Protective effect of green tea extract against proline-induced oxidative damage in the rat kidney.

We investigated, in vivo (acute and chronic), the effects of proline on thiobarbituric acid-reactive substances (TBA-RS) and on the activities of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in renal tissues (cortex and medulla) of rats. For acute administration, 29-day-old rats received a single subcutaneous injection of proline (18.2μmol/g body weight) or an equivalent volume of 0.9% saline solution and were sacrificed 1h later. For chronic treatment, proline was injected subcutaneously in the rats twice a day from the 6th to the 28th day of age, and the animals were killed 12h after the last injection. The results showed that acute administration of proline enhanced CAT, SOD and GSH-Px activities, as well as, TBARS in the cortex and decreased CAT activity in the medulla, while chronic treatment increased the activities of SOD in the cortex and increased CAT, SOD and GSH-Px in the medulla of rats. Furthermore, the green tea extract treatment for one week or from the 6th to the 28th day of age prevented the alterations caused by acute and chronic, respectively, proline administration. Herein, we demonstrated that proline alters antioxidant defenses and induces lipid peroxidation in the kidney of rats and the green tea extract was capable to counteract the proline-induced alterations.

Comparative in vitro study of the effectiveness of Green tea extract and common storage media on periodontal ligament fibroblast viability

Objective:Green tea extract (GTE) was shown to be effective in preserving periodontal ligament fibroblasts (PDLFs) of avulsed teeth. This study aimed at determining the potential of GTE in preserving the viability of PDLFs comparing with different storage media.Materials and Methods:Periodontal ligament cells were obtained from freshly extracted healthy impacted third molars and cultured in Dulbecco's Modified Eagle Medium (DMEM). Cell viability was determined by storing the cells in seven media; DMEM, tap water, Hank's balanced salt solution (HBSS), whole milk, hypotonic sucrose solution, GTE, and GTE + sucrose for 1, 2, 4, and 24 h at 37°C using tetrazolium salt-based colorimetric (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide) assay. Statistical analysis was performed by one-way analysis of variance and post hoc tests.Results:GTE showed significantly higher protective effect than HBSS at 2, 4, and 24 h (P = 0.009, P = 0.02, P = 0.016), DMED at 2 h (P = 0.003), and milk at 4 h (P = 0.039).Conclusion:Although with undesirable osmolality and pH, GTE had a good ability in preserving the PDLFs comparing with other studied media.

Determination of the inhibitory effect of green tea extract on glucose-6-phosphate dehydrogenase based on multilayer capillary enzyme microreactor.

Natural herbal medicines are an important source of enzyme inhibitors for the discovery of new drugs. A number of natural extracts such as green tea have been used in prevention and treatment of diseases due to their low-cost, low toxicity and good performance. The present study reports an online assay of the activity and inhibition of the green tea extract of the Glucose 6-phosphate dehydrogenase (G6PDH) enzyme using multilayer capillary electrophoresis based immobilized enzyme microreactors (CE-IMERs). The multilayer CE-IMERs were produced with layer-by-layer electrostatic assembly, which can easily enhance the enzyme loading capacity of the microreactor. The activity of the G6PDH enzyme was determined and the enzyme inhibition by the inhibitors from green tea extract was investigated using online assay of the multilayer CE-IMERs. The Michaelis constant (Km ) of the enzyme, the IC50 and Ki values of the inhibitors were achieved and found to agree with those obtained using offline assays. The results show a competitive inhibition of green tea extract on the G6PDH enzyme. The present study provides an efficient and easy-to-operate approach for determining G6PDH enzyme reaction and the inhibition of green tea extract, which may be beneficial in research and the development of natural herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd.

Dietary effect of green tea extract on epidermal levels of skin pH related factors, lactate dehydrogenase protein expression and activity in UV-irradiated hairless mice

Purpose: Skin pH, an indicator of skin health, is maintained by various organic factors, which include lactate, free amino acid (FAA), and free fatty acid (FFA). As skin ages or with illness, skin pH becomes less acidic, and functional food has been developed to maintain the acidic pH of skin. In this study, we determined the dietary effect of green tea extract (GTE) on skin pH of photo-aged mice, as measured by epidermal levels of lactate, FAA, and FFA. The protein expression and activity of lactate dehydrogenase (LDH), an enzyme of pyruvate reduction for lactate generation, was further determined. Methods: Albino hairless mice were fed a control diet (group UV+) or a diet with 1% GTE (group GTE) in parallel with UV irradiation for 10 weeks. A normal control group was fed a control diet without UV irradiation for 10 weeks (group UV-). Results: Skin pH was higher (less acidic) in group UV+ than in group UV-. In parallel, epidermal levels of lactate and FFA, as well as of LDH protein expression and activity, were reduced in group UV+. Dietary supplementation of GTE (group GTE) reduced skin pH to similar to the level of group UV-, and inversely increased epidermal levels of lactate, LDH protein expression and activity, but not of FFA. Although epidermal levels of FAA were similar in groups UV- and UV+, it was increased in group GTE to a level higher than in group UV-. In further analysis of major FFA, epidermal levels of palmitic acid [16:0], oleic acid [18:1(n-9)], and linoleic acid [18:2(n-6), but not of stearic acid [18:0] in group GTE were similar to or lower than those in group UV+. Conclusion: Dietary GTE normalized skin pH with increased levels of lactate and FAA, as well as with increased protein expression and activity of LDH in the epidermis of UVB irradiated hairless mice.

Antifungal effect of green tea extracts on oral Candida species: An in vitro study

Background: Candida is one of the commensals housing the normal oral flora. Oral candidiasis is a common opportunistic infection caused by Candida species (Candida albicans being the most common one). Green tea is well-known for its various health benefits, and the literature reveals ongoing studies on the action mechanisms of green tea extract, in vitro and in vivo. Aims and Objectives: The present study was undertaken to assess antifungal effect of green tea extracts; if proven, could it be used in future as an adjunctive treatment modality for treating candidiasis. Materials and Methods: About 15 healthy volunteers with coated tongue were included for the study. Oral sample, from dorsum of the tongue was collected by commercially available pre-sterilized swabs. The material was inoculated into Sabouraud’s Dextrose Agar; confirmed for the presence of Candida species. The sensitivity test was carried out on a lawn culture with 25% and 50% green tea extracts at 24 h and 48 h intervals. The antifungal activity was assessed. Distilled water was used as a control. Student’s paired t-test was used to assess the difference in inhibition effect between 25% and 50% of green tea extract solution. Results: Statistically significant increase in the zone of inhibition was noticed at both 25% and 50% concentration of green tea extracts when compared to control group, which did not show any zone of inhibition. Conclusion: Having shown antifungal effects, the green tea extracts may be considered in future as a therapeutic adjunct.

Dietary effect of green tea extract on hydration improvement and metabolism of free amino acid generation in epidermis of UV-irradiated hairless mice

Purpose: Ultraviolet (UV) irradiation decreases epidermal hydration, which is maintained by reduction of natural moisturizing factors (NMFs). Among various NMFs, free amino acids (AA) are major constituents generated by filaggrin degradation. This experiment was conducted to determine whether or not dietary supplementation of green tea extract (GTE) in UV-irradiated mice can improve epidermal levels of hydration, filaggrin, free AAs, and peptidylarginine deiminase-3 (PAD3) expression (an enzyme involved in filaggrin degradation). Methods: Hairless mice were fed a diet of 1% GTE for 10 weeks in parallel with UV irradiation (group UV+1%GTE). As controls, hairless mice were fed a control diet in parallel with (group UV+) or without (group UV-) UV irradiation. Results: In group UV+, epidermal levels of hydration and filaggrin were lower than those in group UV-; these levels increased in group UV+1% GTE to levels similar to group UV-. Epidermal levels of PAD3 and major AAs of NMF, alanine, glycine and serine were similar in groups UV- and UV+, whereas these levels highly increased in group UV+1% GTE. Conclusion: Dietary GTE improves epidermal hydration by filaggrin generation and degradation into AAs.