Regulating the age-related oxidative damage, mitochondrial integrity, and antioxidative enzyme activity in Fischer 344 rats by supplementation of the antioxidant epigallocatechin-3-gallate

The role of oxidative stress in intervertebral disc degeneration: Mechanisms and therapeutic implications

Oxidative stress is one of the main driving mechanisms of intervertebral disc degeneration(IDD). Oxidative stress has been associated with inflammation in the intervertebral disc, cellular senescence, autophagy, and epigenetics of intervertebral disc cells. It and the above pathological mechanisms are closely linked through the common hub reactive oxygen species(ROS), and promote each other in the process of disc degeneration and promote the development of the disease. This reveals the important role of oxidative stress in the process of IDD, and the importance and great potential of IDD therapy targeting oxidative stress. The efficacy of traditional therapy is unstable or cannot be maintained. In recent years, due to the rise of materials science, many bioactive functional materials have been applied in the treatment of IDD, and through the combination with traditional drugs, satisfactory efficacy has been achieved. At present, the research review of antioxidant bioactive materials in the treatment of IDD is not complete. Based on the existing studies, the mechanism of oxidative stress in IDD and the common antioxidant therapy were summarized in this paper, and the strategies based on emerging bioactive materials were reviewed.

Polymeric Caffeic Acid Acts as an Antigen Delivery Carrier for Mucosal Vaccine Formulation by Forming a Complex with an Antigenic Protein

The development of mucosal vaccines, which can generate antigen-specific immune responses in both the systemic and mucosal compartments, has been recognized as an effective strategy for combating infectious diseases caused by pathogenic microbes. Our recent research has focused on creating a nasal vaccine system in mice using enzymatically polymerized caffeic acid (pCA). However, we do not yet understand the molecular mechanisms by which pCA stimulates antigen-specific mucosal immune responses. In this study, we hypothesized that pCA might activate mucosal immunity at the site of administration based on our previous findings that pCA possesses immune-activating properties. However, contrary to our initial hypothesis, the intranasal administration of pCA did not enhance the expression of various genes involved in mucosal immune responses, including the enhancement of IgA responses. Therefore, we investigated whether pCA forms a complex with antigenic proteins and enhances antigen delivery to mucosal dendritic cells located in the lamina propria beneath the mucosal epithelial layer. Data from gel filtration chromatography indicated that pCA forms a complex with the antigenic protein ovalbumin (OVA). Furthermore, we examined the promotion of OVA delivery to nasal mucosal dendritic cells (mDCs) after the intranasal administration of pCA in combination with OVA and found that OVA uptake by mDCs was increased. Therefore, the data from gel filtration chromatography and flow cytometry imply that pCA enhances antigen-specific antibody production in both mucosal and systemic compartments by serving as an antigen-delivery vehicle.

Oxidative Stress, Reductive Stress and Antioxidants in Vascular Pathogenesis and Aging

This review is focused on the mechanisms that regulate health, disease and aging redox status, the signal pathways that counteract oxidative and reductive stress, the role of food components and additives with antioxidant properties (curcumin, polyphenols, vitamins, carotenoids, flavonoids, etc.), and the role of the hormones irisin and melatonin in the redox homeostasis of animal and human cells. The correlations between the deviation from optimal redox conditions and inflammation, allergic, aging and autoimmune responses are discussed. Special attention is given to the vascular system, kidney, liver and brain oxidative stress processes. The role of hydrogen peroxide as an intracellular and paracrine signal molecule is also reviewed. The cyanotoxins β-N-methylamino-l-alanine (BMAA), cylindrospermopsin, microcystins and nodularins are introduced as potentially dangerous food and environment pro-oxidants.

Epigallocatechin-3-Gallate Alleviates Liver Oxidative Damage Caused by Iron Overload in Mice through Inhibiting Ferroptosis

Ferroptosis, a form of regulated cell death, has been widely explored as a novel target for the treatment of diseases. The failure of the antioxidant system can induce ferroptosis. Epigallocatechin-3-Gallate (EGCG) is a natural antioxidant in tea; however, whether EGCG can regulate ferroptosis in the treatment of liver oxidative damage, as well as the exact molecular mechanism, is unknown. Here, we discovered that iron overload disturbed iron homeostasis in mice, leading to oxidative stress and damage in the liver by activating ferroptosis. However, EGCG supplementation alleviated the liver oxidative damage caused by iron overload by inhibiting ferroptosis. EGCG addition increased NRF2 and GPX4 expression and elevated antioxidant capacity in iron overload mice. EGCG administration attenuates iron metabolism disorders by upregulating FTH/L expression. Through these two mechanisms, EGCG can effectively inhibit iron overload-induced ferroptosis. Taken together, these findings suggest that EGCG is a potential ferroptosis suppressor, and may be a promising therapeutic agent for iron overload-induced liver disease.

Evaluation of the synergistic effects of epigallocatechin-3-gallate-loaded PEGylated-PLGA nanoparticles with nimodipine against neuronal injury after subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a devastating subtype of stroke with high mortality and morbidity. Although serious side effects might occur, nimodipine, a second-generation 1,4-dihydropyridine calcium channel blocker, is clinically used to improve neurological outcomes after SAH. Recently, (-)-epigallocatechin-3-gallate (EGCG) has been reported to inhibit Ca²⁺ overloading-induced mitochondrial dysfunction, oxidative stress, and neuronal cell death after SAH; however, low bioavailability, instability, and cytotoxicity at a high dose limited the clinical application of EGCG. To overcome these limitations, PEGylated-PLGA EGCG nanoparticles (EGCG-NPs) were constructed to enhance the bioavailability by using the double-emulsion method. Antioxidative activity, cytotoxicity, behavioral, and immunohistochemistry studies were carried out to determine the neuroprotective effectiveness after cotreatment with EGCG-NPs (75 mg/kg/d preconditioning for 7 days before SAH) and nimodipine (10 mg/kg/d after 30 min of SAH) by using in vivo SAH models. The optimized EGCG-NPs with a Box-Behnken design showed a small particle size of 167 nm, a zeta potential value of -22.6 mV, an encapsulation efficiency of 86%, and a sustained-release profile up to 8 days in vitro. Furthermore, EGCG-NPs (75 mg/kg/d) had superior antioxidative activity to free EGCG (100 mg/kg/d). EGCG-NPs combined with nimodipine exhibited significant synergistic effects against neuronal cell death by suppressing oxidative stress, Ca²⁺ overloading, mitochondrial dysfunction, and autophagy after SAH. These results suggest that cotreatment with EGCG-NPs and nimodipine may serve as a promising novel strategy for the treatment of SAH.

Epigallocatechin-3-gallate suppresses hemin-aggravated colon carcinogenesis through Nrf2-inhibited mitochondrial reactive oxygen species accumulation

BACKGROUND

Previous studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood.

OBJECTIVES

We aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action.

METHODS

Hemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model.

RESULTS

In Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model.

CONCLUSIONS

We demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.

Green Tea Polyphenol (-)-Epigallocatechin-3-Gallate (EGCG): A Time for a New Player in the Treatment of Respiratory Diseases?

(-)-Epigallocatechin-3-gallate (EGCG) is a major polyphenol of green tea that possesses a wide variety of actions. EGCG acts as a strong antioxidant which effectively scavenges reactive oxygen species (ROS), inhibits pro-oxidant enzymes including NADPH oxidase, activates antioxidant systems including superoxide dismutase, catalase, or glutathione, and reduces abundant production of nitric oxide metabolites by inducible nitric oxide synthase. ECGC also exerts potent anti-inflammatory, anti-fibrotic, pro-apoptotic, anti-tumorous, and metabolic effects via modulation of a variety of intracellular signaling cascades. Based on this knowledge, the use of EGCG could be of benefit in respiratory diseases with acute or chronic inflammatory, oxidative, and fibrotizing processes in their pathogenesis. This article reviews current information on the biological effects of EGCG in those respiratory diseases or animal models in which EGCG has been administered, i.e., acute respiratory distress syndrome, respiratory infections, COVID-19, bronchial asthma, chronic obstructive pulmonary disease, lung fibrosis, silicosis, lung cancer, pulmonary hypertension, and lung embolism, and critically discusses effectiveness of EGCG administration in these respiratory disorders. For this review, articles in English language from the PubMed database were used.

Vascular Protective Effect and Its Possible Mechanism of Action on Selected Active Phytocompounds: A Review

Vascular endothelial dysfunction is characterized by an imbalance of vasodilation and vasoconstriction, deficiency of nitric oxide (NO) bioavailability and elevated reactive oxygen species (ROS), and proinflammatory factors. This dysfunction is a key to the early pathological development of major cardiovascular diseases including hypertension, atherosclerosis, and diabetes. Therefore, modulation of the vascular endothelium is considered an important therapeutic strategy to maintain the health of the cardiovascular system. Epidemiological studies have shown that regular consumption of medicinal plants, fruits, and vegetables promotes vascular health, lowering the risk of cardiovascular diseases. This is mainly attributed to the phytochemical compounds contained in these resources. Various databases, including Google Scholar, MEDLINE, PubMed, and the Directory of Open Access Journals, were searched to identify studies demonstrating the vascular protective effects of phytochemical compounds. The literature had revealed abundant data on phytochemical compounds protecting and improving the vascular system. Of the numerous compounds reported, curcumin, resveratrol, cyanidin-3-glucoside, berberine, epigallocatechin-3-gallate, and quercetin are discussed in this review to provide recent information on their vascular protective mechanisms in vivo and in vitro. Phytochemical compounds are promising therapeutic agents for vascular dysfunction due to their antioxidative mechanisms. However, future human studies will be necessary to confirm the clinical effects of these vascular protective mechanisms.

Bax/Bcl-2 Cascade Is Regulated by the EGFR Pathway: Therapeutic Targeting of Non-Small Cell Lung Cancer

Non-small cell lung carcinoma (NSCLC) comprises 80%-85% of lung cancer cases. EGFR is involved in several cancer developments, including NSCLC. The EGFR pathway regulates the Bax/Bcl-2 cascade in NSCLC. Increasing understanding of the molecular mechanisms of fundamental tumor progression has guided the development of numerous antitumor drugs. The development and improvement of rationally planned inhibitors and agents targeting particular cellular and biological pathways in cancer have been signified as a most important paradigm shift in the strategy to treat and manage lung cancer. Newer approaches and novel chemotherapeutic agents are required to accompany present cancer therapies for improving efficiency. Using natural products as a drug with an effective delivery system may benefit therapeutics. Naturally originated compounds such as phytochemicals provide crucial sources for novel agents/drugs and resources for tumor therapy. Applying the small-molecule inhibitors (SMIs)/phytochemicals has led to potent preclinical discoveries in various human tumor preclinical models, including lung cancer. In this review, we summarize recent information on the molecular mechanisms of the Bax/Bcl-2 cascade and EGFR pathway in NSCLC and target them for therapeutic implications. We further described the therapeutic potential of Bax/Bcl-2/EGFR SMIs, mainly those with more potent and selectivity, including gefitinib, EGCG, ABT-737, thymoquinone, quercetin, and venetoclax. In addition, we explained the targeting EGFR pathway and ongoing in vitro and in vivo and clinical investigations in NSCLC. Exploration of such inhibitors facilitates the future treatment and management of NSCLC.

Epigallocatechin 3-gallate: From green tea to cancer therapeutics

Epigallocatechin 3-gallate (EGCG) possesses various biological functions, including anti-cancer and anti-inflammatory properties. EGCG is an abundant polyphenolic component originating from green tea extract that has exhibited versatile bioactivities in combating several cancers. This review highlights the pharmacological features of EGCG and its therapeutic implications in cancer and other metabolic diseases. It modulates numerous signaling pathways, regulating cells' undesired survival and proliferation, thus imparting strong tumor chemopreventive and therapeutic effects. EGCG initiates cell death through the intrinsic pathway and causes inhibition of EGFR, STAT3, and ERK pathways in several cancers. EGCG alters and inhibits ERK1/2, NF-κB, and Akt-mediated signaling, altering the Bcl-2 family proteins ratio and activating caspases in tumor cells. This review focuses on anti-cancer, anti-oxidant, anti-inflammatory, anti-angiogenesis, and apoptotic effects of EGCG. We further highlighted the potential of EGCG in different types of cancer, emphasizing clinical trials formulations that further improve our understanding of the therapeutic management of cancer and inflammatory diseases.

Epigallocatechin gallate and theaflavins independently alleviate cyclophosphamide-induced ovarian damage by inhibiting the overactivation of primordial follicles and follicular atresia

BACKGROUND

Cyclophosphamide (CTX), which has been used to treat common female cancers for several years, often causes ovarian damage, early menopause and infertility. However, strategies for the effective prevention and treatment of CTX-induced ovarian damage are still lacking. Epigallocatechin gallate (EGCG) and theaflavins (TFs), key molecules derived from green tea or black tea, have been shown to exert preventive effects on many ageing-related diseases.

PURPOSE

We aimed to explore the potential preventive and protective effects of EGCG and TFs on CTX-induced ovarian damage and compare the two compounds.

STUDY DESIGN

Six-week-old female mice were administered a low or high dose of EGCG or TFs. The low dose was equivalent to the average daily amount of tea consumed by a drinker.

METHODS

We determined the oestrous cycle and serum hormone levels to evaluate ovarian endocrine function, and we performed mating tests for reproductivity. We also assessed the follicle count and AMH level to evaluate ovarian reserve, and we performed Masson's trichrome and Sirius red staining to evaluate ovarian fibrosis. We conducted γ-H2AX and TUNEL analyses to evaluate DNA damage, and we also measured the relevant indicators of oxidative stress and follicular activation, including NRF2, HO-1, SOD2, AKT, mTOR and RPS6.

RESULTS

EGCG and TFs treatment independently improved the ovarian endocrine function and reproductivity of mice that were administered CTX. EGCG and TFs also increased the ovarian reserve of these animals. Furthermore, EGCG and TFs alleviated oxidation-induced damage to ovarian DNA in mice by activating the NRF2/HO-1 and SOD2 pathways and reducing the apoptosis of growing follicles. At the same time, EGCG and TFs reduced the overactivation of primordial follicles by inhibiting the AKT/mTOR/RPS6 pathway.

CONCLUSION

The present study showed that EGCG and TFs independently improved ovarian function in mice with CTX-induced ovarian damage, thereby providing useful information for designing a potential clinical strategy that will protect against chemotherapy-induced ovarian damage.

Molecular Determinants of the Cardiometabolic Improvements of Dietary Flavanols Identified by an Integrative Analysis of Nutrigenomic Data from a Systematic Review of Animal Studies

SCOPE

Flavanols are important polyphenols of the human diet with extensive demonstrations of their beneficial effects on cardiometabolic health. They contribute to preserve health acting on a large range of cellular processes. The underlying mechanisms of action of flavanols are not fully understood but involve a nutrigenomic regulation.

METHODS AND RESULTS

To further capture how the intake of dietary flavanols results in the modulation of gene expression, nutrigenomics data in response to dietary flavanols obtained from animal models of cardiometabolic diseases have been collected and submitted to a bioinformatics analysis. This systematic analysis shows that dietary flavanols modulate a large range of genes mainly involved in endocrine function, fatty acid metabolism, and inflammation. Several regulators of the gene expression have been predicted and include transcription factors, miRNAs and epigenetic factors.

CONCLUSION

This review highlights the complex and multilevel action of dietary flavanols contributing to their strong potential to preserve cardiometabolic health. The identification of the potential molecular mediators and of the flavanol metabolites driving the nutrigenomic response in the target organs is still a pending question which the answer will contribute to optimize the beneficial health effects of dietary bioactives.

Phenolic Compounds of Red Wine Aglianico del Vulture Modulate the Functional Activity of Macrophages via Inhibition of NF-κB and the Citrate Pathway

Phenolic compounds of red wine powder (RWP) extracted from the Italian red wine Aglianico del Vulture have been investigated for the potential immunomodulatory and anti-inflammatory capacity on human macrophages. These compounds reduce the secretion of IL-1β, IL-6, and TNF-α proinflammatory cytokines and increase the release of IL-10 anti-inflammatory cytokine induced by lipopolysaccharide (LPS). In addition, RWP restores Annexin A1 levels, thus involving activation of proresolutive pathways. Noteworthy, RWP lowers NF-κB protein levels, promoter activity, and nuclear translocation. As a consequence of NF-κB inhibition, reduced promoter activities of SLC25A1—encoding the mitochondrial citrate carrier (CIC)—and ATP citrate lyase (ACLY) metabolic genes have been observed. CIC, ACLY, and citrate are components of the citrate pathway: in LPS-activated macrophages, the mitochondrial citrate is exported by CIC into the cytosol where it is cleaved by ACLY in oxaloacetate and acetyl-CoA, precursors for ROS, NO^·, and PGE₂ inflammatory mediators. We identify the citrate pathway as a RWP target in carrying out its anti-inflammatory activity since RWP reduces CIC and ACLY protein levels, ACLY enzymatic activity, the cytosolic citrate concentration, and in turn ROS, NO^·, PGE₂, and histone acetylation levels. Overall findings suggest that RWP potentially restores macrophage homeostasis by suppressing inflammatory pathways and activating proresolutive processes.

Polyphenol treatments increase elastin and collagen deposition by human dermal fibroblasts; Implications to improve skin health

BACKGROUND

Skin aging is marked by progressive loss in elastin and collagen that causes wrinkling and sagging of skin. Tropoelastin (TE) is the precursor monomer of elastin secreted by cells that cross-links extracellularly to create functional elastic fibers. Cells maintain the capacity to make TE during the aging process. However, the process of extracellular tropoelastin cross-linking diminishes with age. Others have shown that TE production by cells increases with UV exposure.

OBJECTIVE

We hypothesize that polyphenols may help coacervate cell secreted TE due to its elastin binding property and increase insoluble elastin in human dermal fibroblasts (HDFs). Increase in TE production by short term UV exposure may further improve elastin deposition by polyphenols.

METHODS

We treated HDFs with polyphenols viz epigallocatechin gallate (EGCG) and pentagalloyl glucose (PGG) either with or without intermittent (UVA, 12 min three times a week) exposure for 3, 7, and 14 days.

RESULTS

Polyphenols increased insoluble elastin deposition several folds as compared to control untreated cells. Furthermore, short UVA light exposure led to several-fold increased TE production in HDFs. Still, UVA exposure alone was unable to increase insoluble elastic fibers. When polyphenols were introduced with UVA exposure, insoluble elastin deposition was further enhanced in HDFs (30-45-fold increase). Polyphenol treatments with UVA exposure also led to increased collagen deposition in cell cultures. Polyphenols also prevented cell oxidation during UVA exposure.

CONCLUSIONS

Polyphenols in combination with short exposure to UVA light increase extracellular matrix deposition of elastin and collagen and may improve skin properties.

Mitochondria, Oxidative Stress, cAMP Signalling and Apoptosis: A Crossroads in Lymphocytes of Multiple Sclerosis, a Possible Role of Nutraceutics

Multiple sclerosis (MS) is a complex inflammatory and neurodegenerative chronic disease that involves the immune and central nervous systems (CNS). The pathogenesis involves the loss of blood–brain barrier integrity, resulting in the invasion of lymphocytes into the CNS with consequent tissue damage. The MS etiology is probably a combination of immunological, genetic, and environmental factors. It has been proposed that T lymphocytes have a main role in the onset and propagation of MS, leading to the inflammation of white matter and myelin sheath destruction. Cyclic AMP (cAMP), mitochondrial dysfunction, and oxidative stress exert a role in the alteration of T lymphocytes homeostasis and are involved in the apoptosis resistance of immune cells with the consequent development of autoimmune diseases. The defective apoptosis of autoreactive lymphocytes in patients with MS, allows these cells to perpetuate, within the CNS, a continuous cycle of inflammation. In this review, we discuss the involvement in MS of cAMP pathway, mitochondria, reactive oxygen species (ROS), apoptosis, and their interaction in the alteration of T lymphocytes homeostasis. In addition, we discuss a series of nutraceutical compounds that could influence these aspects.

Green Tea Catechins Induce Inhibition of PTP1B Phosphatase in Breast Cancer Cells with Potent Anti-Cancer Properties: In Vitro Assay, Molecular Docking, and Dynamics Studies

The catechins derived from green tea possess antioxidant activity and may have a potentially anticancer effect. PTP1B is tyrosine phosphatase that is oxidative stress regulated and is involved with prooncogenic pathways leading to the formation of a.o. breast cancer. Here, we present the effect of selected green tea catechins on enzymatic activity of PTP1B phosphatase and viability of MCF-7 breast cancer cells. We showed also the computational analysis of the most effective catechin binding with a PTP1B molecule. We observed that epigallocatechin, epigallocatechin gallate, epicatechin, and epicatechin gallate may decrease enzymatic activity of PTP1B phosphatase and viability of MCF-7 cells. Conclusions: From the tested compounds, epigallocatechin and epigallocatechin gallate were the most effective inhibitors of the MCF-7 cell viability. Moreover, epigallocatechin was also the strongest inhibitor of PTP1B activity. Computational analysis allows us also to conclude that epigallocatechin is able to interact and bind to PTP1B. Our results suggest also the most predicted binding site to epigallocatechin binding to PTP1B.

EGCG Upregulates UCP3 Levels to Protect MIN6 Pancreatic Islet Cells from Interleukin-1β-Induced Apoptosis

Objective

The protective effects of epigallocatechin gallate (EGCG) on interleukin-1β (IL-1β)-induced apoptosis were investigated in murine MIN₆ pancreatic β-cells. The role of uncoupling protein-3 (UCP₃) signaling in this process was also explored.

Methods

After treatment with IL-1β and EGCG, cells were collected and analyzed. Cell viability was measured using the CCK₈ assay and the function of β-cells was evaluated by analyzing insulin secretion. Detection of mitochondrial function in cells was performed by measuring mitochondrial membrane potential, the concentration of ATP and activity of ROS. Apoptosis was analyzed by Hochest33258 staining and flow cytometry. Expression levels of UCP₃ were interrogated using immunohistochemistry, RT-PCR and Western blotting.

Results

Compared with the control group, IL-1β treatment (20nM) for 24 h significantly decreased cell viability and insulin secretion, damaged mitochondrial function and increased ROS activity. Results also showed increased apoptosis and a decrease in UCP₃ expression levels (p<0.01). However, treatment with low (1mM) or high (5mM) concentrations of EGCG significantly decreased IL-1β-induced apoptosis (p<0.01), restored mitochondrial function and subsequently increased UCP₃ levels in IL-1β-induced β-cells (p<0.01).

Conclusion

These results suggest that EGCG protects against IL-1β-induced mitochondrial injury and apoptosis in β-cells through the up-regulation of UCP₃.

The Intrinsic Virtues of EGCG, an Extremely Good Cell Guardian, on Prevention and Treatment of Diabesity Complications

The pandemic proportion of diabesity—a combination of obesity and diabetes—sets a worldwide health issue. Experimental and clinical studies have progressively reinforced the pioneering epidemiological observation of an inverse relationship between consumption of polyphenol-rich nutraceutical agents and mortality from cardiovascular and metabolic diseases. With chemical identification of epigallocatechin-3-gallate (EGCG) as the most abundant catechin of green tea, a number of cellular and molecular mechanisms underlying the activities of this unique catechin have been proposed. Favorable effects of EGCG have been initially attributed to its scavenging effects on free radicals, inhibition of ROS-generating mechanisms and upregulation of antioxidant enzymes. Biologic actions of EGCG are concentration-dependent and under certain conditions EGCG may exert pro-oxidant activities, including generation of free radicals. The discovery of 67-kDa laminin as potential EGCG membrane target has broaden the likelihood that EGCG may function not only because of its highly reactive nature, but also via receptor-mediated activation of multiple signaling pathways involved in cell proliferation, angiogenesis and apoptosis. Finally, by acting as epigenetic modulator of DNA methylation and chromatin remodeling, EGCG may alter gene expression and modify miRNA activities. Despite unceasing research providing detailed insights, ECGC composite activities are still not completely understood. This review summarizes the most recent evidence on molecular mechanisms by which EGCG may activate signal transduction pathways, regulate transcription factors or promote epigenetic changes that may contribute to prevent pathologic processes involved in diabesity and its cardiovascular complications.

Genome-Protecting Compounds as Potential Geroprotectors

Throughout life, organisms are exposed to various exogenous and endogenous factors that cause DNA damages and somatic mutations provoking genomic instability. At a young age, compensatory mechanisms of genome protection are activated to prevent phenotypic and functional changes. However, the increasing stress and age-related deterioration in the functioning of these mechanisms result in damage accumulation, overcoming the functional threshold. This leads to aging and the development of age-related diseases. There are several ways to counteract these changes: 1) prevention of DNA damage through stimulation of antioxidant and detoxification systems, as well as transition metal chelation; 2) regulation of DNA methylation, chromatin structure, non-coding RNA activity and prevention of nuclear architecture alterations; 3) improving DNA damage response and repair; 4) selective removal of damaged non-functional and senescent cells. In the article, we have reviewed data about the effects of various trace elements, vitamins, polyphenols, terpenes, and other phytochemicals, as well as a number of synthetic pharmacological substances in these ways. Most of the compounds demonstrate the geroprotective potential and increase the lifespan in model organisms. However, their genome-protecting effects are non-selective and often are conditioned by hormesis. Consequently, the development of selective drugs targeting genome protection is an advanced direction.

(-)-Epigallocatechin-3-gallate provides neuroprotection via AMPK activation against traumatic brain injury in a mouse model

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. (-)-Epigallocatechin-3-gallate (EGCG) has shown robust neuroprotective effects on various brain injury models in rodents. Herein, we aimed to investigate if EGCG protects against TBI and unravel the underlying mechanisms. A total of 102 mice were used for this study. TBI was induced by controlled cortical impact (CCI). EGCG was given immediately after TBI injury. Neurological functions were accessed by corner test, paw placement, modified neurological severity score, rotarod test, and Morris water maze test. AMPK inhibitor and AMPKα1-knockout mice were used to further study the signaling pathways involved in the observed effects. Our results show that EGCG significantly ameliorated CCI-induced neurological impairment, including spatial learning and memory. EGCG suppressed CCI-induced inflammation and oxidative stress. Furthermore, EGCG downregulated the phosphorylation of IKKα/β, IκBα, and nuclear translocation of NF-κB p65; upregulated AMPK phosphorylation; and altered corresponding changes in the phosphorylation of the downstream target's ribosomal protein S6, AS160, and CaMKKß. Our data demonstrate that EGCG protects against CCI-induced TBI through the activation of the AMPK pathway in mice, suggesting that EGCG might be a promising therapeutic intervention preventing locomotor and cognitive impairments after TBI.

Epigallocatechin-3-Gallate Toxicity in Children: A Potential and Current Toxicological Event in the Differential Diagnosis With Virus-Triggered Fulminant Hepatic Failure

The use of nutraceuticals is considerably increasing worldwide with a demand for organic and clean foods in the last two decades, which is probably incomparable with other periods of our civilization. The consistent application of nutraceuticals and so-called "superfood" may have remarkable effects on the prevention of several chronic diseases, including cancer. Moreover, the increased rate of overweight and obesity in Western countries does not spare childhood and youth, and the number of parents using natural remedies for preventing pediatric illness is vastly increasing worldwide. However, the overwhelming effects on diseases often overshadow the side effects of such nutrition, particularly in societies without millennial experience with botanicals and natural elements. Thus, the final result may be disastrous for some individuals. The liver is the most important and conspicuous target organ of numerous molecular compounds, and the cell damage is particularly striking on the infantile and pediatric liver due to the immaturity of the hepatocytes. Here, we target some generic data on fulminant hepatic failure, the benefits, and toxicity of epigallocatechin-3-gallate, which is one of the major components of green tea, and the histopathology of the "green-tea"-associated liver disease.

Molecular Mechanisms of Epigallocatechin-3-Gallate for Prevention of Chronic Kidney Disease and Renal Fibrosis: Preclinical Evidence

Chronic kidney disease (CKD) is a common public health problem worldwide characterized by gradual decline of renal function over months/years accompanied by renal fibrosis and failure in tissue wound healing after sustained injury. Patients with CKD frequently present with profound signs/symptoms that require medical treatment, mostly culminating in hemodialysis and renal transplantation. To prevent CKD more efficiently, there is an urgent need for better understanding of the pathogenic mechanisms and molecular pathways of the disease pathogenesis and progression, and for developing novel therapeutic targets. Recently, several lines of evidence have shown that epigallocatechin-3-gallate (EGCG), an abundant phytochemical polyphenol derived from Camellia sinensis, might be a promising bioactive compound for prevention of CKD development/progression. This review summarizes current knowledge of molecular mechanisms underlying renoprotective roles of EGCG in CKD based on available preclinical evidence (from both in vitro and in vivo animal studies), particularly its antioxidant property through preservation of mitochondrial function and activation of Nrf2 (nuclear factor erythroid 2-related factor 2)/HO-1 (heme oxygenase-1) signaling, anti-inflammatory activity, and protective effect against epithelial mesenchymal transition. Finally, future perspectives, challenges, and concerns regarding its clinical use in CKD and renal fibrosis are discussed.

Low dose Epigallocatechin Gallate Alleviates Experimental Colitis by Subduing Inflammatory Cells and Cytokines, and Improving Intestinal Permeability

Background: In this study, we investigate the impact of epigallocatechin gallate (EGCG), the most abundant and potent catechin in green tea, on a mouse model of inflammatory bowel disease (IBD) and the underlying mechanisms of action. Methods: C57BL/6J mice were subjected to dextran sulfate sodium (DSS)-induced IBD-like disease and then randomly divided into three groups: Model group (MD), low-dose EGCG group (LE, 20 mg/kg/d), and high-dose EGCG group (HE, 50 mg/kg/d). DSS-induced clinical and macroscopic changes were monitored daily. Intestinal permeability was assessed by FITC-Dextran assay. Results: Both high- and low-dose EGCG treatment alleviated clinical manifestations including body weight loss and disease activity index (DAI) of DSS-induced colitis. The DAI score was significantly improved after two days of EGCG treatment. At the end of the study, the macroscopic severity score (MSS) of HE and LE treatment groups were 2.4 ± 1.2, and 2.2 ± 1.0, respectively, significantly lower than that of the controls (5.0 ± 2.1). EGCG treatment also prevented colon shortening, and improved intestinal permeability and histopathological changes. In addition, EGCG treatment attenuated colon inflammation by suppressing colonic levels of pro-inflammatory cytokines IL-6, MCP-1, and TNF-alpha, and inhibited CD3+ T cell and CD68+ macrophage infiltration. Conclusion: EGCG is effective in inflammatory colitis because it reduces cellular and molecular inflammation, and reduces intestinal permeability.

Regulation of Toll-Like Receptor (TLR) Signaling Pathway by Polyphenols in the Treatment of Age-Linked Neurodegenerative Diseases: Focus on TLR4 Signaling

Neuronal dysfunction initiates several intracellular signaling cascades to release different proinflammatory cytokines and chemokines, as well as various reactive oxygen species. In addition to neurons, microglia, and astrocytes are also affected by this signaling cascade. This release can either be helpful, neutral or detrimental for cell survival. Toll-like receptors (TLRs) activate and signal their downstream pathway to activate NF-κB and pro-IL-1β, both of which are responsible for neuroinflammation and linked to the pathogenesis of different age-related neurological conditions. However, herein, recent aspects of polyphenols in the treatment of neurodegenerative diseases are assessed, with a focus on TLR regulation by polyphenols. Different polyphenol classes, including flavonoids, phenolic acids, phenolic alcohols, stilbenes, and lignans can potentially target TLR signaling in a distinct pathway. Further, some polyphenols can suppress overexpression of inflammatory mediators through TLR4/NF-κB/STAT signaling intervention, while others can reduce neuronal apoptosis via modulating the TLR4/MyD88/NF-κB-pathway in microglia/macrophages. Indeed, neurodegeneration etiology is complex and yet to be completely understood, it may be that targeting TLRs could reveal a number of molecular and pharmacological aspects related to neurodegenerative diseases. Thus, activating TLR signaling modulation via natural resources could provide new therapeutic potentiality in the treatment of neurodegeneration.

Polymeric Caffeic Acid Is a Safer Mucosal Adjuvant That Augments Antigen-Specific Mucosal and Systemic Immune Responses in Mice

Infections remain a major threat to human lives. To overcome the threat caused by pathogens, mucosal vaccines are considered a promising strategy. However, no inactivated and/or subunit mucosal vaccine has been approved for human use, largely because of the lack of a safe and effective mucosal adjuvant. Here, we show that enzymatically synthesized polymeric caffeic acid (pCA) can act as a potent mucosal adjuvant in mice. Intranasal administration of ovalbumin (OVA) in combination with pCA resulted in the induction of OVA-specific mucosal IgA and serum IgG, especially IgG1. Importantly, pCA was synthesized from caffeic acid and horseradish peroxidase from coffee beans and horseradish, respectively, which are commonly consumed. Therefore, pCA is believed to be a highly safe material. In fact, administration of pCA did not show distinct toxicity in mice. These data indicate that pCA has merit for use as a mucosal adjuvant for nasal vaccine formulations.

Neuroprotective effect of epigallocatechin-3-gallate (EGCG) on radiation-induced damage and apoptosis in the rat hippocampus

PURPOSE

This study investigated the potential neuroprotective effect of epigallocatechin-3-gallate (EGCG) on radiation-induced cell death and damage in the hippocampus.

MATERIALS AND METHODS

Adult male Wister rats received oral treatment with EGCG at doses of 2.5 and 5 mg/kg/d for 3 d before 4 Gy γ irradiation.

RESULTS

The pretreatment of irradiated rats with EGCG significantly ameliorated the increased plasma levels of homocysteine, amyloid β, TNF-α and IL-6 levels and the decrease of dopamine and serotonin. Pretreatment with EGCG also significantly ameliorated the irradiation-induced increase in the 4-HNE and protein carbonyl levels and the decreased antioxidants including glutathione level, and the activities of glutathione peroxidase and glutathione reductase in the hippocampus. EGCG treatment prior to radiation exposure protected against DNA damage and apoptosis in the hippocampus. The increase in the levels of p53, Cytochrome-c, Bax and caspases 3 and 9 in the hippocampus were significantly ameliorated with a significant increase in Bcl-2. These changes were supported by marked protection of the dentate gyrus that exhibited a similar histological structure of the control animals.

CONCLUSIONS

EGCG can attenuate the severity of radiation-induced damage and cell death in hippocampus recommending polyphenols as successful option for protecting against radiation-induced hippocampal damage.

An alternative model for studying age-associated metabolic complications: Senescence-accelerated mouse prone 8

Rodent animal models take at least 18months to develop aging phenotypes for researchers to investigate the mechanism of age-related metabolic complications. Senescence-accelerated mouse prone 8 (SAMP8) shortens the process of aging and may facilitate an alternative model for studying age-related insulin resistance. The short-lived strain SAMP8 and two long-lived strains SAM resistant 1 (SAMR1) mice and C57BL/6 mice at 12 (young) and 40weeks old (old) were used in the present study. Glucose tolerance test, histology and signaling pathways involved in lipid metabolism in adipose tissue and liver and key components of insulin signaling pathway in the skeletal muscle were determined in these three strains. We found that short-lived SAMP8 mice developed symptoms of insulin resistance including hyperglycemia, hyperinsulinemia, and impaired glucose tolerance in association with adipocyte hypertrophy and ectopic lipid accumulation in liver and muscle at 40-wk.-old. Significantly increased serum IL-6, leptin, and resistin levels and adipogenic transcription factor PPARγ and macrophage marker F4/80 mRNA expression in adipose tissues were observed in old SAMP8 mice, compared with that in young SAMP8 mice. Marked increases in SREBP1 and PPARγ and a decrease in PPARα at mRNA level in accordance with activation of mTOR/Akt pathway were contributed to hepatic lipid accumulation in old SAMP8 mice. Down-regulation of insulin signaling pathway including IRβ, IRS1, and AS160 at protein level in skeletal muscle was observed in old SAMP8 mice. At 40-wk.-old, both long-lived SAMR1 and C57BL/6 mice have not been fully developed age-related metabolic disorders including insulin resistance and visceral fat expansion in line with fewer defects in lipid metabolism and skeletal muscle insulin signaling pathway. In conclusion, our data suggest the suitability of the SAMP8 mice as a model for studying age-related metabolic complications.

Green Tea Extracts Epigallocatechin-3-gallate for Different Treatments

Epigallocatechin-3-gallate (EGCG), a component extracted from green tea, has been proved to have multiple effects on human pathological and physiological processes, and its mechanisms are discrepant in cancer, vascularity, bone regeneration, and nervous system. Although there are multiple benefits associated with EGCG, more and more challenges are still needed to get through. For example, EGCG shows low bioactivity via oral administration. This review focuses on effects of EGCG, including anti-cancer, antioxidant, anti-inflammatory, anticollagenase, and antifibrosis effects, to express the potential of EGCG and necessity of further studies in this field.

2,3-Dehydrosilybin A/B as a pro-longevity and anti-aggregation compound

Aging is an unavoidable process characterized by gradual failure of homeostasis that constitutes a critical risk factor for several age-related disorders. It has been unveiled that manipulation of various key pathways may decelerate the aging progression and the triggering of age-related diseases. As a consequence, the identification of compounds, preferably natural-occurring, administered through diet, with lifespan-extending, anti-aggregation and anti-oxidation properties that in parallel exhibit negligible side-effects is the main goal in the battle against aging. Here we analyze the role of 2,3-dehydrosilybin A/B (DHS A/B), a minor component of silymarin used in a plethora of dietary supplements. This flavonolignan is well-known for its anti-oxidative and neuroprotective properties, among others. We demonstrate that DHS A/B confers oxidative stress resistance not only in human primary cells but also in the context of a multi-cellular aging model, namely Caenorhabditis elegans (C. elegans) where it also promotes lifespan extension. We reveal that these DHS A/B outcomes are FGT-1 and DAF-16 dependent. We additionally demonstrate the anti-aggregation properties of DHS A/B in human cells of nervous origin but also in nematode models of Alzheimer's disease (AD), eventually leading to decelerated progression of AD phenotype. Our results identify DHS A/B as the active component of silymarin extract and propose DHS A/B as a candidate anti-aging and anti-aggregation compound.

Effects of Epigallocatechin Gallate on Tert-Butyl Hydroperoxide-Induced Mitochondrial Dysfunction in Rat Liver Mitochondria and Hepatocytes

Epigallocatechin gallate (EGCG) is a green tea antioxidant with adverse effects on rat liver mitochondria and hepatocytes at high doses. Here, we assessed whether low doses of EGCG would protect these systems from damage induced by tert-butyl hydroperoxide (tBHP). Rat liver mitochondria or permeabilized rat hepatocytes were pretreated with EGCG and then exposed to tBHP. Oxygen consumption, mitochondrial membrane potential (MMP), and mitochondrial retention capacity for calcium were measured. First, 50 μM EGCG or 0.25 mM tBHP alone increased State 4 Complex I-driven respiration, thus demonstrating uncoupling effects; tBHP also inhibited State 3 ADP-stimulated respiration. Then, the coexposure to 0.25 mM tBHP and 50 μM EGCG induced a trend of further decline in the respiratory control ratio beyond that observed upon tBHP exposure alone. EGCG had no effect on MMP and no effect, in concentrations up to 50 μM, on mitochondrial calcium retention capacity. tBHP led to a decline in both MMP and mitochondrial retention capacity for calcium; these effects were not changed by pretreatment with EGCG. In addition, EGCG dose-dependently enhanced hydrogen peroxide formation in a cell- and mitochondria-free medium. Conclusion. Moderate nontoxic doses of EGCG were not able to protect rat liver mitochondria and hepatocytes from tBHP-induced mitochondrial dysfunction.

Dietary (-)-Epigallocatechin-3-gallate Supplementation Counteracts Aging-Associated Skeletal Muscle Insulin Resistance and Fatty Liver in Senescence-Accelerated Mouse

Aging is accompanied by pathophysiological changes including insulin resistance and fatty liver. Dietary supplementation with (-)-epigallocatechin-3-gallate (EGCG) improves insulin sensitivity and attenuates fatty liver disease. We hypothesized that EGCG could effectively modulate aging-associated changes in glucose and lipid metabolism in senescence-accelerated mice (SAM) prone 8 (SAMP8). Higher levels of glucose, insulin, and free fatty acid, inhibited Akt activity, and decreased glucose transporter 4 (GLUT4) expression were observed in SAMP8 mice compared to the normal aging group, SAM resistant 1 mice. EGCG supplementation for 12 weeks successfully decreased blood glucose and insulin levels via restoring Akt activity and GLUT4 expression and stimulating AMPKα activation in skeletal muscle. EGCG up-regulated genes involved in mitochondrial biogenesis and subsequently restored mitochondrial DNA copy number in skeletal muscle of SAMP8 mice. Decreased adipose triglyceride lipase and increased sterol regulatory element binding proteins-1c (SREBP-1c) and carbohydrate responsive element binding protein at mRNA levels were observed in SAMP8 mice in accordance with hepatocellular ballooning and excess lipid accumulation. The pevention of hepatic lipid accumulation by EGCG was mainly attributed to down-regulation of mTOR and SREBP-1c-mediated lipid biosynthesis via suppression of the positive regulator, Akt, and activation of the negative regulator, AMPKα, in the liver. EGCG beneficially modulates glucose and lipid homeostasis in skeletal muscle and liver, leading to alleviation of aging-associated metabolic disorders.

In vitro toxicity of epigallocatechin gallate in rat liver mitochondria and hepatocytes

Epigallocatechin-3-gallate (EGCG) is the main compound of green tea with well-described antioxidant, anti-inflammatory, and tumor-suppressing properties. However, EGCG at high doses was reported to cause liver injury. In this study, we evaluated the effect of EGCG on primary culture of rat hepatocytes and on rat liver mitochondria in permeabilized hepatocytes. The 24-hour incubation with EGCG in concentrations of 10 μmol/L and higher led to signs of cellular injury and to a decrease in hepatocyte functions. The effect of EGCG on the formation of reactive oxygen species (ROS) was biphasic. While low doses of EGCG decreased ROS production, the highest tested dose induced a significant increase in ROS formation. Furthermore, we observed a decline in mitochondrial membrane potential in cells exposed to EGCG when compared to control cells. In permeabilized hepatocytes, EGCG caused damage of the outer mitochondrial membrane and an uncoupling of oxidative phosphorylation. EGCG in concentrations lower than 10 μmol/L was recognized as safe for hepatocytes in vitro.

New insights into the mechanisms of polyphenols beyond antioxidant properties; lessons from the green tea polyphenol, epigallocatechin 3-gallate

Green tea is rich in polyphenol flavonoids including catechins. Epigallocatechin 3-gallate (EGCG) is the most abundant and potent green tea catechin. EGCG has been extensively studied for its beneficial health effects as a nutriceutical agent. Based upon its chemical structure, EGCG is often classified as an antioxidant. However, treatment of cells with EGCG results in production of hydrogen peroxide and hydroxyl radicals in the presence of Fe (III). Thus, EGCG functions as a pro-oxidant in some cellular contexts. Recent investigations have revealed many other direct actions of EGCG that are independent from anti-oxidative mechanisms. In this review, we discuss these novel molecular mechanisms of action for EGCG. In particular, EGCG directly interacts with proteins and phospholipids in the plasma membrane and regulates signal transduction pathways, transcription factors, DNA methylation, mitochondrial function, and autophagy to exert many of its beneficial biological actions.

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Many biological actions of EGCG are mediated by specific mechanisms other than its well-known anti-oxidant properties.

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EGCG is a pro-oxidant per se in some biological contexts.

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EGCG directly interacts with cell surface membrane proteins and specific known receptors.

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Treatment of cells with EGCG regulates specific intracellular signaling pathways and transcription.

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Specific biological actions of EGCG are regulated in a concentration-dependent manner.

Polyphenols: benefits to the cardiovascular system in health and in aging

Numerous studies have demonstrated the importance of naturally occurring dietary polyphenols in promoting cardiovascular health and emphasized the significant role these compounds play in limiting the effects of cellular aging. Polyphenols such as resveratrol, epigallocatechin gallate (EGCG), and curcumin have been acknowledged for having beneficial effects on cardiovascular health, while some have also been shown to be protective in aging. This review highlights the literature surrounding this topic on the prominently studied and documented polyphenols as pertaining to cardiovascular health and aging.

Inhibition of oxidative stress by low-molecular-weight polysaccharides with various functional groups in skin fibroblasts

The aim of this study was to evaluate the in cellulo inhibition of hydrogen-peroxide-induced oxidative stress in skin fibroblasts using different low-molecular-weight polysaccharides (LMPS) prepared from agar (LMAG), chitosan (LMCH) and starch (LMST), which contain various different functional groups (i.e., sulfate, amine, and hydroxyl groups). The following parameters were evaluated: cell viability, intracellular oxidant production, lipid peroxidation, and DNA damage. Trolox was used as a positive control in order to allow comparison of the antioxidant efficacies of the various LMPS. The experimentally determined attenuation of oxidative stress by LMPS in skin fibroblasts was: LMCH > LMAG > LMST. The different protection levels of these LMPS may be due to the physic-chemical properties of the LMPS' functional groups, including electron transfer ability, metal ion chelating capacities, radical stabilizing capacity, and the hydrophobicity of the constituent sugars. The results suggest that LMCH might constitute a novel and potential dermal therapeutic and sun-protective agent.

The use of transcriptomics to unveil the role of nutrients in Mammalian liver

Liver is the organ primarily responding to diet, and it is crucial in determining plasma carbohydrate, protein, and lipid levels. In addition, it is mainly responsible for transformation of xenobiotics. For these reasons, it has been a target of transcriptomic analyses. In this review, we have covered the works dealing with the response of mammalian liver to different nutritional stimuli such as fasting/feeding, caloric restriction, dietary carbohydrate, cholesterol, fat, protein, bile acid, salt, vitamin, and oligoelement contents. Quality of fats or proteins has been equally addressed, and has the influence of minor dietary components. Other compounds, not purely nutritional as those represented by alcohol and food additives, have been included due to their relevance in processed food. The influence has been studied not only on mRNA but also on miRNA. The wide scope of the technology clearly reflects that any simple intervention has profound changes in many metabolic parameters and that there is a synergy in response when more compounds are included in the intervention. Standardized arrays to systematically test the same genes in all studies and analyzing data to establish patterns of response are required, particularly for RNA sequencing. Moreover, RNA is a valuable, easy-screening ally but always requires further confirmation.

Supplementation with essential amino acids in middle age maintains the health of rat kidney

Chronic kidney diseases are a social and economic problem, and diet has long been recognized as a fundamental modulator of kidney health in human and experimental models. Age-dependent alterations in mitochondrial function play a crucial role in the development of diseases of aging, and mitochondrial disorders have been observed in experimental models of kidney failure. Recently, the beneficial dietary effect of a specific mixture of essential amino acids (EAA) has been studied in elderly subjects, but no data were collected from the kidney. The aim of this study was to assess whether daily supplementation of the diet with EAA at the beginning of senescence could preserve renal health. We used middle-aged (18-month-old) male Wistar rats fed a standard diet and water ad libitum (M-aged group) or a diet with added EAA (1.5 g/kg per day) dissolved in drinking water for 3 months (M-aged+EAA group). Young (2-month-old) rats fed a standard diet for 3 months were used as controls. Mitochondrial morphology and markers for collagen, cyt-c-oxidase, HSP60, GRP75, eNOS, iNOS, Bax, Bcl2 and VEGF were analyzed in glomeruli and tubules. EAA supplementation limited fibrosis and increased the capillary tuft area in the glomeruli of M-aged rats. VEGF and eNOS were enhanced in glomeruli and the peritubular space with the EAA-supplemented diet. Mitochondrial cyt-c oxidase, Bcl2, and chaperones increased in the distal tubules of the EAA group to levels similar to those observed in the young group. Mitochondrial area and density after EAA intake did not differ from young groups. The results suggest that prolonged EAA intake could represent a strategy for maintaining the healthy status of the kidney in M-aged animals.

Functional genomics of endothelial cells treated with anti-angiogenic or angiopreventive drugs

Angiogenesis is a highly regulated physiological process that has been studied in considerable detail given its importance in several chronic pathologies. Many endogenous factors and hormones intervene in the regulation of angiogensis and classical as well as targeted drugs have been developed for its control. Angiogenesis inhibition has come off the bench and entered into clinical application for cancer therapy, particularly for metastatic disease. While the clinical benefit is currently in terms of months, preclinical data suggest that novel drugs and drug combinations could lead to substantial improvement. The many targets of endogenous angiogenesis inhibitors reflect the complexity of the process; in contrast, current clinical therapies mainly target the vascular endothelial growth factor system. Cancer chemopreventive compounds can retard tumor insurgence and delay or prevent metastasis and many of these molecules hinder angiogenesis, a mechanism that we termed angioprevention. Angiopreventive drugs appear to prevalently act through the inhibition of the pro-inflammatory and anti-apoptotic player NFkappaB, thus contrasting inflammation dependent angiogenesis. Relatively little is known concerning the effects of these angiogenesis inhibitors on gene expression of endothelial cells, the main target of many of these molecules. Here we provide an exhaustive list of anti-angiogenic molecules, and summarize their effects, where known, on the transcriptome and functional genomics of endothelial cells. The regulation of specific genes can be crucial to preventive or therapeutic intervention. Further, novel targets might help to circumvent resistance to anti-angiogenic therapy. The studies we review are relevant not only to cancer but also to other chronic degenerative diseases involving endothelial cells, such as cardiovascular disorders, diabetes, rheumatoid arthritis and retinopaties, as well as vessel aging.