Tea Polyphenols Supplementation Research Articles

Dietary tea polyphenol supplementation and its impacts on growth performance, plasma parameters, and antioxidant capacity of juvenile genetically improved farmed tilapia (GIFT: Oreochromis niloticus )

Dietary tea polyphenol supplementation and its impacts on growth performance, plasma parameters, and antioxidant capacity of juvenile genetically improved farmed tilapia (GIFT: <i>Oreochromis niloticus</i> )

Effects of dietary tea polyphenols on intestinal microflora and metabonomics in juvenile hybrid sturgeon (Acipenser baerii♀ × A. schrenckii ♂)

The present study aimed to evaluate the role of the modulatory effect of Tea polyphenols (TPs) on intestinal microbiota and its metabolism of juvenile hybrid sturgeon. A total of 450 fish (97.20 ± 0.18 g) were fed five diets with different concentrations of TPs mg / kg: 0 (TP-0), 100 (TP-100), 300 (TP-300), 500 (TP-500) and 1000 (TP-1000) for 56 days. The results showed that dietary 300 mg / kg TPs significantly increased villus height (VH), crypt depth (CD) and the number of goblet cells (GC) in the intestine (p < 0.05), and 1000 mg/kg TPs supplementation significantly decreased muscle thickness (MT) and villus width (VW) compared with TP-0 group (p < 0.05). With the increase of dietary TPs, relative abundance of the potential probiotics including Lactobacillus and Rhodobacteraceae were increased, while the relative abundance of potential pathogens especially Clostridiaceae were decreased. And dietary TPs at 300 mg / kg could be beneficial to its self-colonization in the intestinal microflora of sturgeon. Metabonomics analysis showed that the differential amino acids metabolites were increased and amino acids metabolism pathways were enriched with the increase of dietary TPs. The highest enriched pathways in the intestines of sturgeon were tryptophan metabolism, and protein digestion and absorption metabolism with the increase of TPs supplementation at 300 mg / kg. These results provide a novel insight into the immune-protective effect of TPs on regulating the intestinal microbiota and metabolism, which are helpful for thoroughly understanding the function of TPs and providing a solid basis for the deeper utilization of TPs as a natural feed additives.

Effect of tea polyphenols supplement on growth performance, antioxidation, and gut microbiota in squabs.

Early life nutritional supplementation can significantly improve pigeon health. Both the nutritional crops of parental pigeons and the intestinal development of squabs play key roles in the growth rate of squabs. Tea polyphenols (TPs), as natural plant extracts, exhibit potential biological activities. However, the impact of TPs on the intestinal function of squabs is not known. This study evaluated the effects of TPs on growth performance, immunity, antioxidation, and intestinal function in squabs. A total of 432 young pigeons (1 day old) were divided into four groups: a control group (fed a basic diet) and three treatment groups (low, medium, and high dose groups; 100, 200, and 400 mg/kg TPs, respectively). On the 28th day, samples of serum, mucosal tissue, and digests from the ileum of squabs were collected for analysis. The results revealed that TP supplementation significantly reduced the feed-to-meat ratio and improved the feed utilization rate and serum biochemical indices in squabs. Additionally, it enhanced the intestinal barrier function of birds by promoting intestinal development and integrity of tight junctions and regulating digestive enzyme activities and intestinal flora. Mechanistically, TPs activated the Nrf2-ARE signaling pathway, which may be associated with improved antioxidant and immune responses, correlating with an increased abundance of Candida arthritis and Corynebacterium in the ileum.

P03-001-23 Effect of Green Tea Polyphenol Supplementation on Serum Lipids and Iron Biomarkers in Women With Obesity: Double-Blind, Placebo-Controlled Trial—A Pilot Study

P03-001-23 Effect of Green Tea Polyphenol Supplementation on Serum Lipids and Iron Biomarkers in Women With Obesity: Double-Blind, Placebo-Controlled Trial—A Pilot Study

Supplementation of tea polyphenols in sludge Fenton oxidation improves sludge dewaterability and reduces chemicals consumption

The Fenton oxidation improves sludge dewatering but faces notable technical and economic challenges, including a narrow acidic pH range, slow reduction of Fe(III), and the use of high doses of chemicals. Herein, we used a natural polyhydroxyphenol tea polyphenols (TP), as an iron redox conversion enhancer, to mitigate these issues. Compared with the classical Fenton process at pH 3.0, the process with TP (33.8 mg/g dry solids (DS)) improved sludge dewaterability at pH 7.5 in a Fenton-like system with faster Fe(II)/Fe(III) cycling and two times lower consumption of the Fenton reagent. Sludge capillary suction time and specific resistance to filtration decreased from 70 s to 22 s and from 2.7 × 1013 m/kg to 5.2 × 1011 m/kg, respectively, while the required doses of Fe(II) and H2O2 were cut to 25 mg/g DS and 31.2 mg/g DS. Mechanistically, TP could bond readily with Fe(II)/Fe(III) at neutral pH to form stable complexes with complexation constants of 34 ± 161 M−1 and 52 ± 70 M−1, respectively, and reduce part of the Fe(III) to Fe(II) simultaneously. This maintained sufficient soluble Fe in the sludge and boosted efficient conversion of Fe(II)/Fe(III) to yield more hydroxyl radicals (•OH). Subsequently, •OH oxidation resulted in the decomposition of biopolymers with a molecular weight of 108 Da (e.g., 58.2% of polysaccharides and 31.6% of proteins in tightly bound extracellular polymeric substances) into small molecules and disintegration of bioflocs into smaller particles with increased porosity, contact angle, and cell lysis; these changes helped reduce bound water content and improved sludge dewaterability. In addition, the TP-mediated Fenton process disinfected fecal coliforms in the sludge and preserved the sludge organic matters. This work proposes a new paradigm for developing cost-effective sludge dewatering technologies that relies on the synergistic effects of plant polyphenols and advanced oxidation processes.

Tea polyphenols protect mice from acute ethanol-Induced liver injury by modulating the gut microbiota and short-chain fatty acids

• Effect of tea polyphenols (TPs) protected against acute alcoholic liver injury were tested. • TPs remarkably influenced gut microbiota composition and abundance. • TPs significantly increased the amounts of Porphyromonadaceae and Coriobacteriaceae at the family level. • TPs elevated the abundance of propionic acid, butyric acid and valeric acid in ethanol gavaged mice. • The strong correlation between gut microbiota abundance and short-chain fatty acids levels were observed. Tea polyphenols (TPs), naturally present in green tea, have a number of health benefits, such as alleviating hepatic injury. Acute alcoholic liver injury was induced in C57BL/6 male mice by 40% ethanol gavage, and the mice were treated with distilled water or TPs in drinking water (4 g/L, 0.4%) for 8 weeks. The results demonstrated that TPs intake alleviated acute alcoholic liver injury and modulated the gut microbiota composition and abundance. TPs supplementation elevated the abundance of propionic acid, butyric acid and valeric acid in ethanol-gavaged mice. Enterorhabdus , Parvibacter , Desulfovibrio , Saccharibacteria_genera_incertae_sedis , Barnesiella , Eubacterium, and Clostridium XVIII showed positive correlations with short-chain fatty acids (SCFAs). Our study confirmed that TPs can alleviate acute alcoholic liver injury by altering the composition of the gut microbiota and SCFAs.

Dietary emulsifier and antioxidant improved astaxanthin utilization and antioxidant capacity of rainbow trout ( Oncorhynchus mykiss )

This study investigated the effects of dietary emulsifiers and antioxidants on astaxanthin utilization and antioxidant capacity of rainbow trout. First, 50 and 100 mg kg−1 of synthetic astaxanthin (AST-50 and AST-100) were added to the control diet (Con), then 400 mg kg−1 sodium taurocholate (ST), 100 mg kg−1 tea polyphenols (TP) and 100 mg kg−1 surfactin (SUR) were added to the AST-50 diet. The six diets were fed to rainbow trout (6.69 ± 0.02) g for 6 weeks. No significant differences were found in weight gain and feed conversion ratio among all the diets (p > .05). The flesh redness (a*), yellowness (b*) and the astaxanthin content in flesh and liver were significantly increased in fish fed with ST, TP and SUR diets compared with the CON fish, but these values were lower than that in fish fed with AST-100 diet (p < .05). Diets involving TP and SUR significantly enhanced T-AOC in flesh, serum and liver, whereas T-SOD was decreased than those of AST-50 and ST diets (p < .05). In conclusion, the supplementation of tea polyphenols and surfactant in the diet effectively improved the astaxanthin deposition and antioxidant capacity of rainbow trout, and sodium taurocholate promoted the deposition of astaxanthin, rather than the antioxidant capacity.

Tea polyphenol alleviate Aeromonas hydrophila - induced intestinal physical barrier damage in grass carp (Ctenopharyngodon idella)

This study aimed to investigate the effects of tea polyphenol (TP) supplementation on attenuating Aeromonas hydrophila - induced intestinal barrier function injury in fish. A total of 540 healthy grass carp (187.49 ± 0.66 g) were randomly divided into six groups with three replicates and fed TP-supplemented diets at 0, 40, 80, 120, 160 and 200 mg/kg for 60 days. After the growth trial, 24 fish per group were randomly selected for a challenge test with A. hydrophila for 6 days. The results indicated that an appropriate level of TP (120 mg/kg diet) repair damaged the intestinal morphology of fish induced by A. hydrophila. Additionally, appropriate level of TP ameliorated the intestinal apical junctional complex partly, which was partly related to the up-regulation of the expressions of tight junction and adherent junction proteins via the RhoA/ROCK pathway in the fish intestine. Based on the results of this research, dietary TP supplementation possesses a protective function of the intestinal physical barrier in fish against A. hydrophila, making TP a functional feed additive for aquaculture and providing a solution for the issue of hazards to human health caused by antibiotic residues in aquatic food.

Different effects of two dietary levels of tea polyphenols on the lipid deposition, immunity and antioxidant capacity of juvenile GIFT tilapia (Oreochromis niloticus) fed a high-fat diet

Long-term feeding of fish with a high-fat diet (HFD) causes excess fat deposition and an impairment of immune function. In the present study, we aimed to determine whether dietary tea polyphenols (TPs) would ameliorate the adverse effects of HFD-feeding in GIFT tilapia. Juvenile GIFT tilapias (5.4 ± 0.9 g) were raised in twelve 200-L tanks (three tanks per diet, 20 fish per tank) and fed a control diet (6% fat, 36% protein), an HFD (12% fat, 36% protein), or an HFD supplemented with 50 mg/kg or 200 mg/kg TP for 8 weeks. The fish were hand-fed 5% of their body weight per day in three feeds, and maintained at 28 ± 1 °C under a 14-h light/10-h dark cycle. The fish in each tank were bulk weighed and counted fortnightly, and the daily feed amount was adjusted accordingly. At the end of the trial, the cumulative survival rate was calculated, and the weight gain and feed conversion ratio were calculated according to the bulk weight of fish in each tank. Tissues were collected from nine fish per diet, their organs were weighed, and biochemical and molecular indices were subsequently measured. HFD-feeding significantly increased lipid deposition, reduced cumulative survival from 96% to 75%, reduced hepatic alkaline phosphate activity (AKP) and serum total antioxidant capacity (T-AOC); and reduced the hepatic expression of immunoglobulin M (IgM), transforming growth factor-beta (TGF-β) and glutathione-S-transferase (GST) genes versus the control diet. The addition of TPs at 50 or 200 mg/kg both ameliorated the HFD-induced increase in lipid droplets in the liver (50 mg/kg TP from 40.83% to 17.27%; 200 mg/kg TP to 25.33%), and increased the cumulative survival rate of the tilapia. The addition of 50 mg/kg TP had a marked effect increasing cumulative survival to 90%, and increasing the activities of serum acid phosphatase (ACP), T-AOC; and IgM, TGF-β, nuclear factor-κB (NF-κB), superoxide dismutase (SOD), and GST gene expression to the highest level of the HFD-fed groups. The 50 mg/kg TP-containing diet also significantly increased the hepatic expression of carnitine palmitoyltransferase 1 alpha (CPT1α) versus the control diet. In contrast, the tilapia fed an HFD supplemented with 200 mg/kg TPs had the lowest expression of adipose triglyceride lipase, hormone-sensitive lipase, CPT1α, fatty acid synthase and acetyl-CoA carboxylase alpha genes of any of the groups, which implies that the lower and higher levels of TP supplementation have differing effects on lipid metabolism. The 200 mg/kg supplement had lower cumulative survival rate (82%), and smaller effects on serum ACP and hepatic AKP activities than the 50 mg/kg dose, and had no significant effect on serum T-AOC or the expression of IgM, TGF-β, GST, or NF-κB genes in the tilapia. These results indicate that the beneficial effects of TPs on the lipid metabolism and health of fish fed an HFD are dose-related. Moreover, they are likely to be largely mediated through lipid catabolism.

Tea polyphenols increase the antioxidant status of laying hens fed diets with different levels of ageing corn.

This study was conducted to evaluate the effects of ageing corn levels (stored for 4 years) with or without the supplementation of tea polyphenols (TPP) on the performance, egg quality and antioxidant status of laying hens. A total of 288 Lohmann commercial laying hens (63-week-old) were used under a 2 × 4 factorial arrangement with 4 levels of dietary ageing corn (0%, 25%, 50%, or 100%) and 2 levels of TPP (0 and 600 mg/kg) for 8 wk. Dietary ageing corn linearly decreased (P < 0.05) the egg production, serum total antioxidant capacity (T-AOC), liver glutathione peroxidase (GSH-Px) of laying hens, yolk index, yolk colour, 1,1-diphenyl-2-picrylhydrazyl (DPPH) value and the reducing power value of egg yolk, but it linearly increased (P < 0.05) the feed conversion rate, ovary malondialdehyde (MDA) content of laying hens, and the protein carbonyl content of egg yolk. Tea polyphenol supplementation increased (P < 0.05) the serum T-AOC, serum superoxide dismutase (SOD), liver SOD, liver GSH-Px, ovary SOD, GSH-Px, the expression of antioxidant-related genes of laying hens, albumen height, Haugh unit, DPPH value and the majority free amino acids of egg yolk, but it decreased (P < 0.05) the serum MDA content of laying hens, MDA and protein carbonyl of egg yolk. In conclusion, the ageing corn significantly reduced the performance, egg quality, antioxidant status and egg antioxidant capacity of laying hens, while TPP supplementation partially counteracted the adverse effects, especially antioxidant status and egg antioxidant capacity of laying hens.

Green tea polyphenols supplementation alters immunometabolism and oxidative stress in dairy cows with hyperketonemia

Peripartal cows often experience negative energy balance, and are therefore prone to suffering from metabolic diseases such as hyperketonemia, which causes financial losses in dairy farms. This study aimed to investigate the effect of green tea polyphenol (GTP) supplementation during the periparturient period on production performance, oxidative stress and immunometabolism in dairy cows with hyperketonemia. One hundred Holstein cows were assigned to GTP (0.2 g/kg DM; n = 50) or control (without GTP; n = 50) group based on body weight, previous milk yield, and parity on d 15 before expected parturition. Subsequently, 10 cows with hyperketonemia were selected from each group, according to blood β-hydroxybutyric acid (BHBA) concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum. All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum. Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10, 20, and 30 d postpartum. Compared with control cows, greater milk yield and lower somatic cell count were observed in GTP cows. The GTP group had lower concentrations of BHBA, free fatty acids, cholesterol, triglyceride, reactive oxygen species, malondialdehyde, and hydrogen peroxide, greater concentrations of glucose, lower activities of aspartate aminotransferase, alanine aminotransferase, and glutamyl transpeptidase, alongside greater activities of superoxide dismutase, glutathione peroxidase, and total antioxidant capacity. Additionally, GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10, but down-regulated concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-2, interleukin-8, and interferon-γ in plasma. Greater concentrations of plasma immunoglobulin G were also detected in the GTP group. Overall, the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hyperketonemia during early lactation.

Effect of tea polyphenols on flavour, healthcare components, physicochemical properties, and mechanisms of collagen synthesis in growing grass carp (Ctenopharyngodon idella) muscle

Tea polyphenols (TP) are functional feed additives (antioxidants) derived from tea. Research to date has not investigated the impacts of TP on flavour quality, healthcare components, and physicochemical parameters of fish flesh. This study aimed to investigate whether dietary TP in growing grass carp could provide high quality fish flesh. 540 fish (187.49 ± 0.66 g) were fed six diets with different concentrations of TP (0, 40, 80, 120, 160 and 200 mg / kg) for 60 days to determine the effects of TP on flesh quality. The results demonstrated that appropriate dietary TP supplementation benefits growing grass carp in the following respects: (1) promoting performance of growth and nutritional value of fish, (2) enhancing flavour of flesh by increasing the levels of umami-taste free amino acids (glutamic acid and aspartic acid) (3) increasing healthcare components of flesh particularly eicosapentaenoic acid (EPA 20:5n-3) and docosahexaenoic acid (DHA 22:6n-3), (4) improving physicochemical properties (firmness,pH, water-holding capacity) of flesh. The present research explores, for the first time, the effects of TP on enhancing the collagen content, which is partly correlated with the upregulation of type I collagen synthesis genes Col1α1 and Col1α2, mediated through transforming growth factor-β1 (TGF-β1) by Smad pathway in fish muscle. Based on growth performance (percentage weight gain) and fish flesh quality indices (EPA, DHA, shear force, and pH), the appropriate dietary supplementation of TP in growing grass carp were assessed to be 103.01, 116.30, 106.60, 141.15 and 113.49 mg/kg, using quadratic regression analysis. In summary, TP is a promising feed additive to improve fish flesh quality.

Effect of different tea polyphenol products on egg production performance, egg quality and antioxidative status of laying hens

This study was conducted to determine the effects of different tea polyphenol (TP) products on egg production performance, egg quality and antioxidative status of laying hens. A total of 840 Lohmann pink shell laying hens (36-week-old) were randomly divided into 7 treatments for a 12-week feeding trial. The control group was fed a basal diet (no exogenous TP addition), and the experimental groups were fed the basal diet supplemented with approximately 1000 mg/kg of 6 types of tea polyphenols. The TP contents in 6 experimental diets were 1086.1, 944.2, 1111.4, 1037.9, 1074.1, and 1081.7 mg/kg and the caffeine concentrations were 4.4, 17.2, 30.9, 37.5, 73.8, and 128.5 mg/kg, respectively. In terms of performance, TP (except 1086.1 and 1074.1 mg/kg) reduced (P < 0.05) the average daily feed intake (ADFI) and the feed conversion ratio (FCR) during 1–4 week. Dietary TP supplementation at 944.2, 1074.1 and 1081.7 mg/kg increased the dirty egg rate (P < 0.01) and the addition of 1111.4, 1037.9 and 1081.7 mg/kg TP in basal diet decreased saleable egg rate (P < 0.05) during week 5 to week 8. The eggshell strength and eggshell weight of fresh egg at week 0, week 4 and week 8 were decreased by dietary TP supplementation (P < 0.05), with the TP groups (1074.1 and 1081.7 mg/kg) exhibiting the lowest eggshell strength and shell weight at week 0 and week 8. In addition, the lightness (L*) of eggshell color was decreased (P < 0.05), while the redness (a*) and yellowness (b*) was increased as TP intake increased (except 1086.1 and 1037.9 mg/kg) (P < 0.05). The albumen weight, yolk color, relative yolk weight and HU (Haugh unit) of fresh eggs at week 8 were higher or decreased (P < 0.05) as TP intake (except 1086.1 and 1074.1 mg/kg) increased. After 20-day storage, the eggshell strength, eggshell thickness and egg weight of eggs from hens fed the diets supplemented more than 1111.4 mg/kg TP (except 1074.1 mg/kg) were lower (P < 0.05) than those from control group. No effect of TP administration was found on serum glutathione peroxidase (GSH-PX), total antioxidant capacity (T-AOC), and malondialdehyde (MDA) concentrations. The results indicated that adding different tea polyphenol products in layers’ diet led to a lower ADFI and improved FCR in a dosage-dependent manner during the first 4 weeks, but it impacted the hens’ egg quality.

Dietary tea polyphenols induce changes in immune response and intestinal microbiota in Koi carp, cryprinus carpio

We evaluated the effects of dietary tea polyphenols (TP) on growth, immune response and intestinal bacterial community in Koi carp (cryprinus carpio). One hundred and eighty fish were randomly assigned to a basal diet or three treatments consisting of basal diet supplemented with three dosage of TP. Body weight were measured at the beginning and end of trial. Blood and intestinal samples were collected at the end of trial to determine immune response and intestinal bacterial community. The results indicated that lipase activity increased in the TP-500 and TP-1000 treatments (P = 0.0007). Dietary TP decreased the concentration of serum IL-1β, IL-6, lysozyme, complement C4 and C3 (P < 0.0001; P < 0.0001; P = 0.0007; P < 0.0001; P = 0.0365, respectively). No differences was observed in the body weight, protease and amylase activities, and serum TNF-α among the treatment and control groups. Proteobacteria was more abundance in the TP-500 and TP-1000 treatments compared to that in control (P = 0.0346; P = 0.0005), whereas Fusobacteria was less abundance in the TP-1000 treatment (P = 0.0008). Intestinal bacteria, indicated by simpson and shannon indices, was more diverse in the TP-1000 treatment. The principal coordinate analysis (PCoA) based on weighted UniFrac distance indicated that bacterial community of the TP-1000 or TP-500 treatment was separated from that of control (P = 0.001; P = 0.008). In conclusion, dietary supplementation of TP had anti-inflammation effects, but attenuated non-specific immune response. These TP-mediated changes in immune response may be associated with the structure of intestinal bacterial community.

Tea polyphenol protects against cisplatin-induced meiotic defects in porcine oocytes.

DDP (cisplatin), a DNA cross-linking agent, is one of the most common chemotherapeutic drugs that have been widely used in the treatment of sarcomas and germ cell tumors. DDP treatment exhibits severe side effects including renal toxicity, ototoxicity and embryo-toxicity. Women of reproductive age treated with DDP may lead to loss of primordial follicles, resulting in the depletion of the ovarian reserve and consequent premature ovarian failure. However, the influence of DDP on the oocyte quality and the strategy to prevent it has not yet fully clarified. Here, we report that DDP exposure resulted in the oocyte meiotic failure via disrupting the meiotic organelle dynamics and arrangement, exhibiting a prominently impaired cytoskeleton assembly, including spindle formation and actin polymerization. In addition, exposure to DDP led to the abnormal distribution of mitochondrion and cortical granules, two indicators of cytoplasmic maturation of oocytes. Conversely, TP (tea polyphenols) supplementation partially restored all of the meiotic defects resulted from DDP exposure through suppressing the increase of ROS level and the occurrence of DNA damage as well as apoptosis.

Effects of Dietary Green Tea Polyphenol Supplementation on the Health of Workers Exposed to High-voltage Power Lines.

Effects of Dietary Green Tea Polyphenol Supplementation on the Health of Workers Exposed to High-voltage Power Lines.

Effects of Dietary Green Tea Polyphenol Supplementation on the Health of Workers Exposed to High-voltage Power Lines

Effects of Dietary Green Tea Polyphenol Supplementation on the Health of Workers Exposed to High-voltage Power Lines

Tea polyphenols protect bovine mammary epithelial cells from hydrogen peroxide-induced oxidative damage in vitro by activating NFE2L2/HMOX1 pathways

Periparturient dairy cows are likely subject to altered intracellular reduction-oxidation (redox) balance due to the high metabolic rates and physiological adaptations occurring around parturition. Such conditions could induce oxidative damage. In nonruminants, it is well established that nuclear factor erythroid 2 like 2 (NFE2L2) is a critical transcription factor for maintaining cellular redox balance by inducing adaptive responses against oxidative stress (OS) that can otherwise lead to uncontrolled inflammation. Tea polyphenols (TP), the major polyphenolic constituents of green tea, are potent antioxidants that could exert protective effects on bovine mammary epithelial cells (BMEC) by scavenging free radicals. We used NFE2L2 short interfering RNA (siRNA) to downregulate NFE2L2 expression in cultured BMEC to investigate whether TP could inhibit H2O2-induced OS by activating the NFE2L2/heme oxygenase-1 (HMOX1) pathway. Isolated BMEC were exposed to H2O2 (600 μM) for 6 h to induce OS. Optimal doses of TP (0, 60, 80, and 100 μg/mL) were evaluated by pretreatment of BMEC for 0, 2, 4, 6, 8, 12, and 24 h, followed by a H2O2 (600 μM) challenge for 6 h. The BMEC were transfected with NFE2L2-siRNA for 48 h, pretreated with 100 µg/mL of TP for 12 h, then challenged by 600 μM H2O2 for 6 h. Results revealed that after H2O2 exposure a concentration of TP of 100 μg/mL during a 12-h incubation led to greater cell viability, protein, and mRNA abundance of NFE2L2, and lower intracellular reactive oxygen species (ROS) accumulation. In addition, transfection with NFE2L2-siRNA decreased abundance of NFE2L2 and HMOX1 in spite of exogenous TP supplementation, whereas ROS production was increased in response to exogenous H2O2 (600 μM). Overall, TP had beneficial effects on redox balance in BMEC, slowing down cellular OS-related injury through decreasing the production of ROS and enhancing mechanisms controlled at least in part by the NFE2L2/HMOX1 pathway.

Effect of Long-Term Green Tea Polyphenol Supplementation on Bone Architecture, Turnover, and Mechanical Properties in Middle-Aged Ovariectomized Rats.

We investigated the effects of 6-month green tea polyphenols (GTP) supplementation on bone architecture, turnover, and mechanical properties in middle-aged ovariectomized (OVX) rats. Female rats were sham-operated (n = 39, 13/group) or OVX (n = 143, 13/group). Sham-control and OVX-control rats (n = 39) receiving no GTP were assigned for sample collection at baseline, 3, or 6months. The remaining OVX rats (n = 104) were randomized to 0.15%, 0.5%, 1%, and 1.5% (g/dL) GTP for 3 or 6months. Blood and bone samples were collected. Relative to the OVX-control group, GTP (1% and 1.5%) lowered serum procollagen type 1 N-terminal propeptide at 3 and 6months, C-terminal telopeptides of type I collagen at 3months, and insulin-like growth factor-I at 6months. GTP did not affect bone mineral content and density. At 6months, no dose of GTP positively affected trabecular bone volume based on microCT, but a higher cortical thickness and improved biomechanical properties of the femur mid-diaphysis was observed in the 1.5% GTP-treated group. At 3 and 6months, GTP (0.5%, 1%, and 1.5%) had lower rates of trabecular bone formation and resorption than the OVX-control group, but the inhibitory effects of GTP on periosteal and endocortical bone mineralization and formation at the tibial midshaft were only evident at 3months. GTP at higher doses suppressed bone turnover in the trabecular and cortical bone of OVX rats and resulted in improved cortical bone structural and biomechanical properties, although it was not effective in preventing the ovariectomy-induced dramatic cancellous bone loss.

The Protective Roles of Dietary Selenium Yeast and Tea Polyphenols on Growth Performance and Ammonia Tolerance of Juvenile Wuchang Bream (Megalobrama amblycephala).

In order to investigate protective roles of dietary selenium yeast (SY) and tea polyphenols (TPs) on growth of juvenile Wuchang bream (Megalobrama amblycephala) and its resistance under ammonia stress, juvenile Wuchang bream were randomly assigned into four groups: a control group fed basal diets and three treatment groups fed basal diets supplemented with 0.50 mg/kg SY, 50 mg/kg TPs and a combination of 0.50 mg/kg SY and 50 mg/kg TPs, respectively. After 60 days of feeding, growth parameters of Wuchang bream were measured along with serum hormones and the transcription of growth axis-related genes. Then fish were exposed to ammonia stress of 22.5 mg/L total ammonia nitrogen. Hepatic oxidative damage parameters, antioxidant responses and ultrastructure were evaluated before ammonia exposure (0 h) and at 3, 6, 12, 24, and 48 h after ammonia exposure. Results show that before ammonia exposure, the growth parameters, serum GH and IGF-1 levels as well as the growth axis-related gene expression (gh, ghr2 and igf-1) for the SY and combination groups were higher than those determined for the fish on the control diet. In contrast, the administration of TP alone didn’t have significant effects on the growth parameters and growth-related hormones. After ammonia exposure, compared with the control, remarkable increases in the activity and mRNA expression of hepatic antioxidant enzymes (glutathione peroxidase and catalase superoxide dismutase) in three treatment groups were observed along with decreases of hepatic malondialdehyde and protein carbonylation levels, indicating that the single and combined supplementation of SY and TPs could enhance antioxidant capacity to alleviate oxidative stress and damage by ammonia. Consistent with this finding, alterations of the liver ultrastructure in three treatment groups were less severe and faster recovery than in the control group after ammonia exposure. In conclusion, a basal diet supplemented with the combination of 0.50 mg/kg SY and 50 mg/kg TPs could has very beneficial effects on the whole aspects of the growth and ammonia resistance in Wuchang bream juveniles.