‘Induction of inflammatory gene expression by THP-1 macrophages cultured in normocholesterolaemic hypertensive sera and modulatory effects of green tea polyphenols’

Green and Oolong Tea Extracts With Different Phytochemical Compositions Prevent Hypertension and Modulate the Intestinal Flora in a High-Salt Diet Fed Wistar Rats

Green tea (GT) and oolong tea (OLT) are widely consumed beverages, and their preventive and regulatory effects on hypertension have been reported. However, the interventional effects of GT and OLT on hypertension induced by a high-salt diet and its mechanism have not been fully explored. This study evaluated the anti-hypertensive effects of GT and OLT and their underlying mechanisms. The in vivo anti-hypertensive effects of GT and OLT and their capability to prevent hypertension and regulate the intestinal microbiota in Wistar rats fed with a high-salt diet were evaluated. Our results show that GT and OLT supplementations could regulate oxidative stress, inflammation, gene expression, and parameter levels related to blood pressure (BP) and prevent the increase in BP induced by a high-salt diet. Furthermore, both GT and OLT boosted the richness and diversity of intestinal microbiota, increased the abundance of beneficial bacteria and reduced the abundance of harmful bacteria and conditionally pathogenic bacteria, and regulated the intestinal microbial metabolism pathway related to BP. Among them, OLT presented better effects than GT. These findings indicate that GT and OLT can prevent hypertension caused by high-salt diets, which may be due to the regulation of intestinal flora by GT and OLT.

Green Tea from the Far East to the Drug Store: Focus on the Beneficial Cardiovascular Effects

Cardiovascular diseases (CVD) are the leading cause of death worldwide. Evidence from observational and randomized controlled studies showing the potential benefits of green tea on lowering CVD risk has been emerging rapidly during the past few decades. These benefits include reduced risk for major cardiovascular events, lowering of blood pressure, decreased LDL cholesterol levels and weight loss. At the same time, the understanding of the physiological mechanisms behind these alterations is advancing. Consumption of green tea originated from China thousands of years ago, but since then, it expanded all over the world. Recent advances in understanding the role of tea polyphenols, mainly catechins, as mediators of tea's health benefits, have caused the emergence of various types of green tea extracts (GTE) on the market. While taking green tea is generally considered safe, there are concerns about the safety of using tea extracts. The present article reviews the current evidence of green tea consumption leading to reduced CVD risk, its potential biological mechanisms and the safety of using GTE.

Dietary supplementation of Huangshan Maofeng green tea preventing hypertension of older C57BL/6 mice induced by desoxycorticosterone acetate and salt

Senile hypertension affects the life quality of aged population. Dietary intervention plays a pivotal role in the prevention of hypertension. There are few reports concerning the effects and mechanisms of green tea supplementation preventing age related hypertension. The current study investigated the effect and mechanism of dietary supplement of Huangshan Maofeng green tea (HSMF) on prevention of hypertension induced by deoxycorticosterone acetate (DOCA) and salt in old C57BL/6 mice. Our results showed that HSMF dose-dependently prevented the increase of systolic blood pressure and diastolic blood pressure induced by DOCA plus salt (DS) at 51-week-old mice. And HSMF significantly reduced the agonists' stimulated contraction of mesenteric arteries isolated from the old mice. The expression of vasoconstrictor genes and inflammatory cytokines in aorta were suppressed observably by HSMF supplementation compared with DS group. The protein expression of PKCα in the aorta was dose-dependently decreased by HSMF compared to DS group. The phosphorylation level of MYPT1, CPI-17and MLC20 was also restrained by HSMF in the aorta. Furthermore, HSMF protected kidney by maintaining integrity of glomeruli and tubules and remarkably decreased the NGAL level in plasma. HSMF also suppressed the kidney inflammation by decreasing inflammatory cytokines expression and the macrophage infiltration. Our results proved that dietary supplement of HSMF remarkably improved the vascular functions and protected kidney injury, and thus prevented hypertension induced by DS in older C57BL/6 mice. Our data indicated that the dietary supplement of HSMF may potentially be used as a food additive for preventing hypertension for aged people.

Health Benefits and Chemical Composition of Matcha Green Tea: A Review

Japanese matcha is a type of powdered green tea, grown in a traditional way. Shading of the plants during the growth period enhances the processes of synthesis and accumulation of biologically active compounds, including theanine, caffeine, chlorophyll and various types of catechins. Green tea contains four main catechins, i.e., (-)-epicatechin (EC), (-)-epicatechin-3-gallate (ECG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin-3-gallate (EGCG), of which the latter is the most active and abundant and matcha is their best condensed source. Due to its unique chemical composition and prized flavour, which sets it apart from other tea beverages, it is considered the highest quality tea. Its health-promoting properties are attributed to the high content of antioxidant and anti-inflammatory substances. Studies confirming the high antioxidant potential of tea beverages claim that it originates from the considerable content of catechins, a type of phenolic compound with beneficial effects on human health. Due to its potential for preventing many diseases and supporting cognitive function, regular consumption of matcha may have a positive effect on both physical and mental health. The aim of this review was to compile the health benefits of matcha tea. It is the first such review to be undertaken, and presents its main bioactive compounds in a systematic manner.

Effects and Mechanisms of Tea Regulating Blood Pressure: Evidences and Promises

Cardiovascular diseases have overtaken cancers as the number one cause of death. Hypertension is the most dangerous factor linked to deaths caused by cardiovascular diseases. Many researchers have reported that tea has anti-hypertensive effects in animals and humans. The aim of this review is to update the information on the anti-hypertensive effects of tea in human interventions and animal studies, and to summarize the underlying mechanisms, based on ex-vivo tissue and cell culture data. During recent years, an increasing number of human population studies have confirmed the beneficial effects of tea on hypertension. However, the optimal dose has not yet been established owing to differences in the extent of hypertension, and complicated social and genetic backgrounds of populations. Therefore, further large-scale investigations with longer terms of observation and tighter controls are needed to define optimal doses in subjects with varying degrees of hypertensive risk factors, and to determine differences in beneficial effects amongst diverse populations. Moreover, data from laboratory studies have shown that tea and its secondary metabolites have important roles in relaxing smooth muscle contraction, enhancing endothelial nitric oxide synthase activity, reducing vascular inflammation, inhibiting rennin activity, and anti-vascular oxidative stress. However, the exact molecular mechanisms of these activities remain to be elucidated.

Dietary Polyphenols-Important Non-Nutrients in the Prevention of Chronic Noncommunicable Diseases. A Systematic Review

The improvement of the social and economic conditions of society has eliminated the threat of death from the majority of infectious diseases. However, the rapid progress of civilization has created new possibilities for the appearance of factors with adverse effects for the health of society. This has led to increased morbidity from certain diseases, the presence of which had not been observed several centuries ago. Chronic noncommunicable diseases (e.g., cancers, cardio-vascular disorders, diabetes, obesity, neurodegenerative diseases) result from an inappropriate relationship between people and their environment. The common characteristic for all chronic diseases is a “new” form of inflammation, very often called metaflammation, which is considered as a subclinical, permanent inflammation. As a result, metabolic cascade, including cellular oxidative stress, atherosclerotic process, and insulin resistance, occurs, which slowly generates significant deterioration in the organism. Polyphenols are the major group of non-nutrients, considering their diversity, food occurrence, and biological properties. The current review aims to present a wide spectrum of literature data, including the molecular mechanism of their activity and experimental model used, and summarize the recent findings on the multitude of physiological effects of dietary polyphenols towards the prevention of several chronic diseases. However, despite several studies, the estimation of their dietary intake is troublesome and inconclusive, which will be also discussed.

Preventive Effects of Catechins on Cardiovascular Disease

Catechins are polyphenolic phytochemicals with many important physiological activities that play a multifaceted health care function in the human body, especially in the prevention of cardiovascular disease. In this paper, various experimental and clinical studies have revealed the role of catechins in the prevention and treatment of cardiovascular disorders, and we review the preventive effects of catechins on cardiovascular disease from the following aspects: Regulating lipid metabolism, regulating blood lipid metabolism, vascular endothelial protection, and reducing blood pressure.

Short-Term Adjuvant Therapy with Terminalia arjuna Attenuates Ongoing Inflammation and Immune Imbalance in Patients with Stable Coronary Artery Disease: In Vitro and In Vivo Evidence

The present study evaluated the cardioprotective effects of Terminalia arjuna on classical and immuno-inflammatory markers in coronary artery disease (CAD) as an adjuvant therapy. One hundred sixteen patients with stable CAD were administered placebo/T. arjuna (500 mg twice a day) along with medications in a randomized, double-blind clinical trial. To understand the specificity and efficacy of T. arjuna, we evaluated its effect through microarray and in silico analysis in few representative samples. Data was further validated via real-time PCR (n = 50) each at baseline, 3 months, and 6 months, respectively. rIL-18 cytokine was used to induce inflammation in vitro to compare its effects with atorvastatin. T. arjuna significantly down-regulated TG, VLDL-C, and immuno-inflammatory markers in stable CAD versus placebo-treated subjects. Microarray and pathway analysis of a few samples from T. arjuna/placebo-treated groups and real-time PCR validation further confirmed our observations. Our data demonstrate the anti-inflammatory and immunomodulatory effects of T. arjuna that may attenuate ongoing inflammation and immune imbalance in medicated CAD subjects.

Biomimetic preparation of polymer-supported free radical scavenging, cytocompatible and antimicrobial "green" silver nanoparticles using aqueous extract of Citrus sinensis peel

In the pursuit of making the nanoscale-research greener, the utilization of the reductive potency of a common byproduct of food processing industry i.e. orange peel is reported here to prepare biopolymer-templated "green" silver nanoparticles. Aqueous extract of orange peel at basic pH was exploited to prepare starch supported nanoparticles under ambient conditions. The compositional abundance of pectins, flavonoids, ascorbic acid, sugars, carotenoids and myriad other flavones may be envisaged for the effective reductive potential of orange peel to generate silver nanoparticles. The nanoparticles were distributed within a narrow size spectrum of (3-12 nm) with characteristic Bragg's reflection planes of fcc structure, and surface plasmon resonance peak at 404 nm. Anti-lipid peroxidation assay using goat liver homogenate and DPPH scavenging test established the anti-oxidant potency of the silver nanoparticles. Their synergy with rifampicin against Bacillus subtilis MTCC 736 and cytocompatibility with the human leukemic monocytic cell line, THP-1 were also investigated. Thus, the present work deals with the preparation of starch assisted anti-microbial, cytocompatible and free radical scavenging "green" silver nanoparticles.

In vitro modulation of peroxisome proliferator-activated receptor-gamma and its genes by C-reactive protein. Role of atorvastatin

BACKGROUND AND AIMS

C-reactive protein (CRP) serves not only as a biomarker for the risk of cardiovascular disease and underlying inflammation but also functions as an active mediator of atherosclerosis by promoting activation of endothelial cells and monocytes. Peroxisome proliferator activated receptor-gamma (PPAR-gamma) transcription factor has been recognized to regulate the expression of many genes involved in inflammation, lipid metabolism and vascular remodeling. Therefore, in the present study we tried to explore the role of CRP as a possible mediator of atherosclerosis by determining its effect on PPAR-gamma and its effector genes, i.e., liver X receptor-alpha (LXR-alpha) and matrix metalloproteinase-9 (MMP-9) in THP-1 cells.

METHODS

Semi-quantitative RT-PCR was used to determine mRNA expression.

RESULTS

CRP upregulates the expression of PPAR-gamma and LXR-alpha at lower doses (5-25 microg/mL), which were further declined at higher doses (50-100 microg/mL). However, a dose-dependent increase was observed for MMP-9 expression. Atorvastatin (10-20 microM) was able to significantly accelerate the CRP-induced expression of PPAR-gamma and LXR-alpha and attenuate MMP-9 expression.

CONCLUSIONS

For the first time we demonstrate that CRP modulates PPAR-gamma and its effector genes and reinforces the mechanistic link of CRP as a possible mediator in atherosclerosis and also advocate atorvastatin as a therapeutic modality.

Modulation of gene expression by Polyalthia longifolia in postmenopausal women with coronary artery disease: an in vitro study

Chronic underlying inflammation is involved in the pathophysiology of coronary artery disease (CAD). Polyalthia longifolia var. pendula bark extract (PLE) is known to exhibit anti-inflammatory activity and has high content of phytosteroids. Since phytosteroids mimic estrogen structurally, we postulated that PLE may provide protection in postmenopausal women against CAD. Thus the effect of PLE has been explored on expression of estrogen receptors (ERalpha and ERbeta) and inflammatory inducible nitric oxide synthase (iNOS) genes in vitro in peripheral blood mononuclear cells (PBMCs) obtained from postmenopausal women. A total of 20 postmenopausal women were included in the present study. Group I (N = 10) included women with angiographically proven CAD, and group II (N = 10) is composed of equal number of age-matched healthy postmenopausal females as controls. Significantly low levels of serum 17-beta estradiol were observed in subjects of group I as compared to group II (p < 0.01). A marked increase in L: -citrulline levels (p > 0.05) and significantly augmented levels of reactive nitrogen intermediates (p < 0.05) were observed in group I subjects. PLE significantly attenuated PMA-induced expression of both ERalpha and ERbeta receptors and inflammatory iNOS gene in vitro in a dose- and time-dependent manner and had an additive effect on these genes when compared with tamoxifen. Ours is the first report to demonstrate that PLE contains certain bioactive principles, which possess anti-inflammatory and estrogenic properties, and thereby hold the promise to be screened for their anti-atherogenic potential in experimental animals to favorably alter several other markers of cardiovascular risk.

Green tea consumption is associated with depressive symptoms in the elderly

BACKGROUND

Green tea is reported to have various beneficial effects (eg, anti-stress response and antiinflammatory effects) on human health. Although these functions might be associated with the development and progression of depressive symptoms, no studies have investigated the relation between green tea consumption and depressive symptoms in a community-dwelling population.

OBJECTIVE

The aim of this study was to investigate the relations between green tea consumption and depressive symptoms in elderly Japanese subjects who widely consumed green tea.

DESIGN

We conducted a cross-sectional study in 1058 community-dwelling elderly Japanese individuals aged >or=70 y. Green tea consumption was assessed by using a self-administered questionnaire, and depressive symptoms were evaluated by using the 30-item Geriatric Depression Scale with 2 cutoffs: 11 (mild and severe depressive symptoms) and 14 (severe depressive symptoms). If a participant was consuming antidepressants, he or she was considered to have depressive symptoms.

RESULTS

The prevalence of mild and severe and severe depressive symptoms was 34.1% and 20.2%, respectively. After adjustment for confounding factors, the odds ratios (95% CI) for mild and severe depressive symptoms when higher green tea consumption was compared with green tea consumption of <or=1 cup/d were as follows: 2-3 cups green tea/d (0.96; 95% CI: 0.66, 1.42) and >or=4 cups green tea/d (0.56; 95% CI: 0.39, 0.81) (P for trend: 0.001). Similar relations were also observed in the case of severe depressive symptoms.

CONCLUSION

A more frequent consumption of green tea was associated with a lower prevalence of depressive symptoms in the community-dwelling older population.

C-reactive protein (CRP) up-regulates expression of receptor for advanced glycation end products (RAGE) and its inflammatory ligand EN-RAGE in THP-1 cells: inhibitory effects of atorvastatin

BACKGROUND

Receptor for advanced glycation end products (RAGE) may play an important role in inflammatory processes and endothelial activation. Extracellular newly identified RAGE binding protein (EN-RAGE), natural pro-inflammatory ligand for RAGE. The role of C-reactive protein (CRP) as a mediator in inflammation and atherosclerosis is the subject of recent investigations worldwide. In the present study, we investigated the effect of CRP on RAGE and EN-RAGE gene expression in THP-1 monocytic cell line. MAP kinases (ERK, p38 and JNK) were exploited as possible signaling pathways involved in the signal transduction by CRP. Further, atorvastatin was used as a therapeutic modality for modulation of these genes in the presence of CRP.

MATERIALS AND METHODS

Time and dose-dependent experiments were carried out in the presence of CRP. Specific MAPK pathways inhibitors were used to elucidate the signaling pathways involved. Effect of atorvastatin was also determined in the presence of CRP on the expression of these genes.

RESULTS

Time and dose-dependent experiments revealed that, treatment of THP-1 cells with 100 microg of CRP/ml/10(6) cells for 24 h, augmented the expression of RAGE and EN-RAGE genes by 2.5-3.5 folds and 3.5-4.5 folds respectively. CRP acted via FcgammaRII and utilized ERK, p38 and JNK pathways to transduce signals. Atorvastatin in a dose of 20 muM, was able to attenuate up-regulation of CRP-induced genes (p<0.01) and effects were both dose and time-dependent.

CONCLUSION

Our data strongly suggests that blockade of RAGE-EN-RAGE by statins at an early stage may prevent inflammation in atherosclerosis and counteract the harmful effects mediated by CRP.