Elevation of oxidative-damage biomarkers during aging in F2 hybrid mice: protection by chronic oral intake of resveratrol

Cell senescence in liver diseases: pathological mechanism and theranostic opportunity

The liver is not oblivious to the passage of time, as ageing is a major risk factor for the development of acute and chronic liver diseases. Ageing produces alterations in all hepatic cells, affecting their phenotype and function and worsening the prognosis of liver disease. The ageing process also implies the accumulation of a cellular state characterized by a persistent proliferation arrest and a specific secretory phenotype named cellular senescence. Indeed, senescent cells have key roles in many physiological processes; however, their accumulation owing to ageing or pathological conditions contributes to the damage occurring in chronic diseases. The aim of this Review is to provide an updated description of the pathophysiological events in which hepatic senescent cells are involved and their role in liver disease progression. Finally, we discuss novel geroscience therapies that could be applied to prevent or improve liver diseases and age-mediated hepatic deregulations.

Resveratrol can improve spinal cord injury by activating Nrf2/HO-1 signaling pathway

Spinal cord injury (SCI) often induces severe sensory and motor dysfunction. Oxidative stress is an important pathophysiological process of secondary SCI, and its inhibition could facilitate the alleviation of the injury. Resveratrol is a natural plant polyphenol compound that has significant antioxidant and anti-inflammatory effects. It can inhibit oxidative stress by activating the Nrf2/HO-1 signal pathway. In this report, we analyze the antioxidant effect of resveratrol in SCI, clarify the specific mechanism of action and provide a theoretical basis for the clinical employment of resveratrol for SCI.

A Spectrum of Solutions: Unveiling Non-Pharmacological Approaches to Manage Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a developmental disorder that causes difficulty while socializing and communicating and the performance of stereotyped behavior. ASD is thought to have a variety of causes when accompanied by genetic disorders and environmental variables together, resulting in abnormalities in the brain. A steep rise in ASD has been seen regardless of the numerous behavioral and pharmaceutical therapeutic techniques. Therefore, using complementary and alternative therapies to treat autism could be very significant. Thus, this review is completely focused on non-pharmacological therapeutic interventions which include different diets, supplements, antioxidants, hormones, vitamins and minerals to manage ASD. Additionally, we also focus on complementary and alternative medicine (CAM) therapies, herbal remedies, camel milk and cannabiodiol. Additionally, we concentrate on how palatable phytonutrients provide a fresh glimmer of hope in this situation. Moreover, in addition to phytochemicals/nutraceuticals, it also focuses on various microbiomes, i.e., gut, oral, and vaginal. Therefore, the current comprehensive review opens a new avenue for managing autistic patients through non-pharmacological intervention.

Antiaging effects of dietary supplements and natural products

Aging is an inevitable process influenced by genetics, lifestyles, and environments. With the rapid social and economic development in recent decades, the proportion of the elderly has increased rapidly worldwide, and many aging-related diseases have shown an upward trend, including nervous system diseases, cardiovascular diseases, metabolic diseases, and cancer. The rising burden of aging-related diseases has become an urgent global health challenge and requires immediate attention and solutions. Natural products have been used for a long time to treat various human diseases. The primary cellular pathways that mediate the longevity-extending effects of natural products involve nutrient-sensing pathways. Among them, the sirtuin, AMP-activated protein kinase, mammalian target of rapamycin, p53, and insulin/insulin-like growth factor-1 signaling pathways are most widely studied. Several studies have reviewed the effects of individual natural compounds on aging and aging-related diseases along with the underlying mechanisms. Natural products from food sources, such as polyphenols, saponins, alkaloids, and polysaccharides, are classified as antiaging compounds that promote health and prolong life via various mechanisms. In this article, we have reviewed several recently identified natural products with potential antiaging properties and have highlighted their cellular and molecular mechanisms. The discovery and use of dietary supplements and natural products that can prevent and treat multiple aging-related diseases in humans will be beneficial. Thus, this review provides theoretical background for existing dietary supplements and natural products as potential antiaging agents.

Acetaminophen-induced liver injury: Molecular mechanism and treatments from natural products

Acetaminophen (APAP) is a widely used analgesic and antipyretic over-the-counter medicine worldwide. Hepatotoxicity caused by APAP overdose is one of the leading causes of acute liver failure (ALF) in the US and in some parts of Europe, limiting its clinical application. Excessive APAP metabolism depletes glutathione and increases N-acetyl-p-benzoquinoneimide (NAPQI) levels, leading to oxidative stress, DNA damage, and cell necrosis in the liver, which in turn leads to liver damage. Studies have shown that natural products such as polyphenols, terpenes, anthraquinones, and sulforaphane can activate the hepatocyte antioxidant defense system with Nrf2 as the core player, reduce oxidative stress damage, and protect the liver. As the key enzyme metabolizing APAP into NAPQI, cytochrome P450 enzymes are also considered to be intriguing target for the treatment of APAP-induced liver injury. Here, we systematically review the hepatoprotective activity and molecular mechanisms of the natural products that are found to counteract the hepatotoxicity caused by APAP, providing reference information for future preclinical and clinical trials of such natural products.

Natural Radiosensitizers in Radiotherapy: Cancer Treatment by Combining Ionizing Radiation with Resveratrol

Conventional cancer treatment is mainly based on the surgical removal of the tumor followed by radiotherapy and/or chemotherapy. When surgical removal is not possible, radiotherapy and, less often, chemotherapy is the only way to treat patients. However, despite significant progress in understanding the molecular mechanisms of carcinogenesis and developments in modern radiotherapy techniques, radiotherapy (alone or in combination) does not always guarantee treatment success. One of the main causes is the radioresistance of cancer cells. Increasing the radiosensitivity of cancer cells improves the processes leading to their elimination during radiotherapy and prolonging the survival of cancer patients. In order to enhance the effect of radiotherapy in the treatment of radioresistant neoplasms, radiosensitizers are used. In clinical practice, synthetic radiosensitizers are commonly applied, but scientists have recently focused on using natural products (phytocompounds) as adjuvants in radiotherapy. In this review article, we only discuss naturally occurring radiosensitizers currently in clinical trials (paclitaxel, curcumin, genistein, and papaverine) and those whose radiation sensitizing effects, such as resveratrol, have been repeatedly confirmed by many independent studies.

Medicinal plants used against hepatic disorders in Bangladesh: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Liver disease is a major cause of illness and death worldwide which accounts for approximately 2 million deaths per year worldwide, 1 million due to complications of cirrhosis and 1 million due to viral hepatitis and hepatocellular carcinoma. That's why it is seeking the researchers' attention to find out the effective treatment strategies. Phytochemicals from natural resources are the main leads for the development of noble hepatoprotective drugs. The majority of the natural sources whose active compounds are currently employed actually have an ethnomedical use. Ethnopharmacological research is essential for the development of these bioactive compounds. These studies not only provide scientific evidence on medicinal plants utilized for particular therapeutic purposes, but they also ensure cultural heritage preservation. Plenty of experimental studies have been well-documented that the ethnomedicinal plants are of therapeutics' interest for the advanced pharmacological intervention in terms of hepatic disorders.

AIM OF THE STUDY

This study summarizes the processes of hepatotoxicity induced by various toxins and explores identified hepatoprotective plants and their phytoconstituents, which can guide the extraction of novel phytochemical constituents from plants to treat liver injury. This review aimed to summarize the hepatoprotective activity of Bangladeshi medicinal plants where the bioactive compounds may be leads for the drug discovery in future.

MATERIALS AND METHODS

Literature searches in electronic databases, such as Web of Science, Science Direct, SpringerLink, PubMed, Google Scholar, Semantic Scholar, Scopus, BanglaJOL, and so on, were performed using the keywords 'Bangladesh', 'ethnomedicinal plants', 'Hepatoprotective agents' as for primary searches, and secondary search terms were used as follows, either alone or in combination: traditional medicine, medicinal plants, folk medicine, liver, hepatitis, therapeutic uses, and anti-inflammatory. Besides, several books, including the book entitled "Medicinal plants of Bangladesh: chemical constituents and uses" authored by Abdul Ghani, were carefully considered, which contained pharmacological properties and phytoconstituents of many medicinal plants growing and traditionally available in Bangladesh. Among them, the most promising plant species with their latest therapeutic effects against hepatic disorders were deeply considered in this review.

RESULTS

The results of this study revealed that in most cases, therapy using plant extracts stabilized altered hepatic biochemical markers induced by hepatotoxins. Initially, we investigated 32 plant species for hepatoprotective activity, however after extensive literature searching; we observed that 20 plants offer good pharmacological evidence of hepatoprotective function. Consequently, most bioactive compounds derived from the herbs including berberine, thymoquinone, andrographolide, ursolic acid, luteolin, naringenin, genistein, quercetin, troxerutin, morin, epigallocatechin-3-gallate, chlorogenic acid, emodin, curcumin, resveratrol, capsaicin, ellagic acid, etc. are appeared to be effective against hepatic disorders.

CONCLUSIONS

Flavonoids, phenolic acids, monoterpenoids, diterpenoids, triterpenoids, alkaloids, chromenes, capsaicinoids, curcuminoids, and anthraquinones are among the phytoconstituents were appraised to have hepatoprotective activities. All the actions displayed by these ethnomedicinal plants could make them serve as leads in the formulation of drugs with higher efficacy to treat hepatic disorders.

Effects and Mechanisms of Resveratrol on Aging and Age-Related Diseases

The aging of population has become an issue of great concern because of its rapid increase. Aging is an important risk factor of many chronic diseases. Resveratrol could be found in many foods, such as grapes, red wine, peanuts, and blueberries. Many studies reported that resveratrol possessed various bioactivities, such as antioxidant, anti-inflammatory, cardiovascular protection, anticancer, antidiabetes mellitus, antiobesity, neuroprotection, and antiaging effects. The antiaging mechanisms of resveratrol were mainly ameliorating oxidative stress, relieving inflammatory reaction, improving mitochondrial function, and regulating apoptosis. Resveratrol could be an effective and safe compound for the prevention and treatment of aging and age-related diseases. In this review, we summarize the effects of resveratrol on aging, life extension, and several age-related diseases, with special attention paid to the mechanisms of antiaging action.

Nuclear Genomic Instability and Aging

The nuclear genome decays as organisms age. Numerous studies demonstrate that the burden of several classes of DNA lesions is greater in older mammals than in young mammals. More challenging is proving this is a cause rather than a consequence of aging. The DNA damage theory of aging, which argues that genomic instability plays a causal role in aging, has recently gained momentum. Support for this theory stems partly from progeroid syndromes in which inherited defects in DNA repair increase the burden of DNA damage leading to accelerated aging of one or more organs. Additionally, growing evidence shows that DNA damage accrual triggers cellular senescence and metabolic changes that promote a decline in tissue function and increased susceptibility to age-related diseases. Here, we examine multiple lines of evidence correlating nuclear DNA damage with aging. We then consider how, mechanistically, nuclear genotoxic stress could promote aging. We conclude that the evidence, in toto, supports a role for DNA damage as a nidus of aging.

Risperidone-Induced Renal Damage and Metabolic Side Effects: The Protective Effect of Resveratrol

Objective

The aim of the study was to investigate the possible protective qualities of resveratrol (RSV) against the side effects of risperidone (RIS) in an experimental model in rat kidneys with histologic and biochemical assessments.

Materials and Methods

Experimental procedures were performed on 35 female Sprague Dawley rats. Rats were randomly divided into five groups: control, untreated rats (n = 7) were in group 1; group 2 was given 2 mg/kg/day RIS (n = 7); group 3 was treated with 2 mg/kg/day RIS and 20 mg/kg/day RSV (n = 7); group 4 was treated with 2 mg/kg/day RIS and 40 mg/kg/day RSV (n = 7); and group 5 was treated with 2 mg/kg/day RIS and 80 mg/kg/day RSV (n = 7). All treatments were administered for two weeks by gavage. On treatment day 15, kidney tissues were removed for analysis.

Results

The results showed that RSV treatment reduced weight gain induced by RIS. In addition, RSV increased the total antioxidant status (TAS) and decreased serum creatinine (Cr), blood urea nitrogen (BUN), oxidative stress index (OSI), and total oxidant status (TOS) levels significantly (p < 0.05).

Conclusion

This study revealed that treatment with RSV might protect kidney tissues against the side effects of RIS. RSV could be an effective course of therapy to enhance therapeutic efficacy.

Involvement of miR-539-5p in the inhibition of de novo lipogenesis induced by resveratrol in white adipose tissue

Proposed miRNA mechanisms of action of resveratrol in triacylglycerol metabolism changes in adipose tissue.

Organ and tissue-dependent effect of resveratrol and exercise on antioxidant defenses of old mice

BACKGROUND

Oxidative stress has been considered one of the causes of aging. For this reason, treatments based on antioxidants or those capable of increasing endogenous antioxidant activity have been taken into consideration to delay aging or age-related disease progression.

AIM

In this paper, we determine if resveratrol and exercise have similar effect on the antioxidant capacity of different organs in old mice.

METHODS

Resveratrol (6 months) and/or exercise (1.5 months) was administered to old mice. Markers of oxidative stress (lipid peroxidation and glutathione) and activities and levels of antioxidant enzymes (SOD, catalase, glutathione peroxidase, glutathione reductase and transferase and thioredoxin reductases, NADH cytochrome B5-reductase and NAD(P)H-quinone acceptor oxidoreductase) were determined by spectrophotometry and Western blotting in different organs: liver, kidney, skeletal muscle, heart and brain.

RESULTS

Both interventions improved antioxidant activity in the major organs of the mice. This induction was accompanied by a decrease in the level of lipid peroxidation in the liver, heart and muscle of mice. Both resveratrol and exercise modulated several antioxidant activities and protein levels. However, the effect of resveratrol, exercise or their combination was organ dependent, indicating that different organs respond in different ways to the same stimulus.

CONCLUSIONS

Our data suggest that physical activity and resveratrol may be of great importance for the prevention of age-related diseases, but that their organ-dependent effect must be taken into consideration to design a better intervention.

Hepatoprotective properties of extensively studied medicinal plant active constituents: possible common mechanisms

CONTEXT

We focused on certain plant active constituents considered to be the most promising/studied for liver disease and that were critically investigated from the basic science point of view and, to some extent, the clinical one. Due to insufficient pharmacological data, most of the herbal formulations containing these molecules cannot be recommended for the treatment of liver disease.

OBJECTIVE

To present the most promising compounds tested experimentally and/or clinically and describe in brief popular models in experimental testing of potential hepatoprotective compounds.

METHODS

A literature search using Web of Science (WOS), PubMed, and Google search was performed.

RESULTS

Focusing on a few herbal hepatoprotective active constituents is useful to health professionals working in the field of therapeutics to develop evidence-based hepatoprotective agents by conducting research on pure chemical structures or on molecular modifications using computational chemistry. This review demonstrates that multi-pathways in the liver pathobiology can be interrupted at one or more levels by natural hepatoprotective studied, such as interference with the oxidative stress at multiple levels to reduce reactive oxygen/nitrogen species, resulting in ameliorating hepatotoxicity.

CONCLUSION

Hepatoprotective constituents of herbal medications are poorly absorbed after oral administration; methods that can improve their bioavailability are being developed. It is recommended that controlled prospective double-blind multicenter studies on isolated active plant constituents, or on related newly designed molecules after structural modifications, should be performed. This effort will lead to expanding the existing, limited drugs for the vast majority of liver diseases.

Pifithrin-α ameliorates resveratrol-induced two-cell block in mouse preimplantation embryos in vitro

Treatment with resveratrol at concentrations greater than 0.5 μmol/L resulted in the arrest of mouse embryo development at the two-cell stage. Resveratrol-induced cytotoxicity was investigated in embryos by evaluating morphologic features by using the bromodeoxyuridine assay and acridine orange and ethidium bromide double staining. Resveratrol was found to significantly increase the expressions of p53, p21, Atf3, smac/Diablo, Bax, Bak1, Bok, and Noxa mRNA in the embryos, whereas Cullin 3 and Cdk1 expressions were decreased. Furthermore, active p53 positive signal in embryos arrested at the two-cell stage was localized in the nucleus, whereas no active p53 signal was observed in control embryos. Pretreatment with pifithrin-α, a p53 inhibitor, downregulated active p53 in two-cell embryo nuclei and ameliorated approximately 50% of the embryonic developmental defect caused by resveratrol. The findings of the present study, therefore, suggest that pifithrin-α could be used as an effective cytoprotective agent against a reproductive toxin such as resveratrol.

NaDC3 Induces Premature Cellular Senescence by Promoting Transport of Krebs Cycle Intermediates, Increasing NADH, and Exacerbating Oxidative Damage

High-affinity sodium-dependent dicarboxylate cotransporter 3 (NaDC3) is a key metabolism-regulating membrane protein responsible for transport of Krebs cycle intermediates. NaDC3 is upregulated as organs age, but knowledge regarding the underlying mechanisms by which NaDC3 modulates mammalian aging is limited. In this study, we showed that NaDC3 overexpression accelerated cellular senescence in young human diploid cells (MRC-5 and WI-38) and primary renal tubular cells, leading to cell cycle arrest in G1 phase and increased expression of senescent biomarkers, senescence-associated β-galactosidase and p16. Intracellular levels of reactive oxygen species, 8-hydroxy-2'-deoxyguanosine, malondialdehyde, and carbonyl were significantly enhanced, and activities of respiratory complexes I and III and ATP level were significantly decreased in NaDC3-infected cells. Stressful premature senescent phenotypes induced by NaDC3 were markedly ameliorated via treatment with the antioxidants Tiron and Tempol. High expression of NaDC3 caused a prominent increase in intracellular levels of Krebs cycle intermediates and NADH. Exogenous NADH and NAD(+) may aggravate and attenuate the aging phenotypes induced by NaDC3, respectively. These results suggest that NaDC3 can induce premature cellular senescence by promoting the transport of Krebs cycle intermediates, increasing generation of NADH and reactive oxygen species and leading to oxidative damage. Our results clarify the aging signaling pathway regulated by NaDC3.

Physiological, physical and behavioural changes in dogs (Canis familiaris) when kennelled: testing the validity of stress parameters

Domestic dogs (Canis familiaris) housed in kennelling establishments are considered at risk of suffering poor welfare. Previous research supporting this hypothesis has typically used cortisol:creatinine ratios (C/Cr) to measure acute and chronic stress in kennelled dogs. However, the value of C/Cr as a welfare indicator has been questioned. This study aimed to test the validity of a range of physiological, physical and behavioural welfare indicators and to establish baseline values reflecting good dog welfare. Measurements were taken from 29 privately-owned dogs (14 males, 15 females), ranging in age and breed, in their own home and in a boarding kennel environment, following a within-subjects, counterbalanced design. Pairwise comparisons revealed that C/Cr and vanillylmandelic acid:creatinine ratios (VMA/Cr) were higher in the kennel than home environment (P=0.003; P=0.01, respectively) and were not associated with differences in movement/exercise between environments. Dogs' surface temperature was lower in kennels (P=0.001) and was not associated with ambient temperature. No association with age, or effects of kennel establishment, kennelling experience, sex or source were found. Dogs were generally more active in kennels, but showed considerable individual variability. C/Cr and 5-HIAA:creatinine ratios (5-HIAA/Cr) were negatively correlated with lip licking in kennels. Baseline values for each parameter are presented. The emotional valence of responses was ambiguous and no definitive evidence was found to suggest that dogs were negatively stressed by kennelling. It was concluded that C/Cr and, particularly, VMA/Cr and surface temperature provide robust indicators of psychological arousal in dogs, while spontaneous behaviour might be better used to facilitate interpretation of physiological and physical data on an individual level.

Combination of low dose of the anti-adipogenic agents resveratrol and phenelzine in drinking water is not sufficient to prevent obesity in very-high-fat diet-fed mice

PURPOSE

Resveratrol inhibits lipid accumulation but suffers from limited bioavailability. The anti-depressive agent phenelzine limits adipogenesis in various models of cultured preadipocytes, and this hydrazine derivative also inhibits de novo lipogenesis in mature adipocytes. It was therefore tested whether resveratrol effects on adiposity reduction and glucose tolerance improvement could be reinforced by co-administration with phenelzine.

METHODS

Mice fed a very-high-fat diet (VHFD, 60% calories as fat) were subjected to drinking solution containing low dose of resveratrol (0.003%) and/or 0.02% phenelzine for 12 weeks. Body fat content, glucose tolerance, food and water consumption were checked during treatment while fat depot mass was determined at the end of supplementation. Direct influence of the agents on lipogenesis and glucose uptake was tested in adipocytes.

RESULTS

Epididymal fat depots were reduced in mice drinking phenelzine alone or with resveratrol. No limitation of body weight gain or body fat content was observed in the groups drinking resveratrol or phenelzine, separately or in combination. The altered glucose tolerance and the increased fat body composition of VHFD-fed mice were not reversed by resveratrol and/or phenelzine. Such lack of potentiation between resveratrol and phenelzine prompted us to verify in vitro their direct effects on mouse adipocytes. Both molecules inhibited de novo lipogenesis, but did not potentiate each other at 10 or 100 μM. Only resveratrol inhibited hexose uptake in a manner that was not improved by phenelzine.

CONCLUSIONS

Phenelzine has no interest to be combined with low doses of resveratrol for treating/preventing obesity, when considering the VHFD mouse model.

Sirtuin1 and autophagy protect cells from fluoride-induced cell stress

Sirtuin1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD(+))-dependent deacetylase functioning in the regulation of metabolism, cell survival and organismal lifespan. Active SIRT1 regulates autophagy during cell stress, including calorie restriction, endoplasmic reticulum (ER) stress and oxidative stress. Previously, we reported that fluoride induces ER-stress in ameloblasts responsible for enamel formation, suggesting that ER-stress plays a role in dental fluorosis. However, the molecular mechanism of how cells respond to fluoride-induced cell stress is unclear. Here, we demonstrate that fluoride activates SIRT1 and initiates autophagy to protect cells from fluoride exposure. Fluoride treatment of ameloblast-derived cells (LS8) significantly increased Sirt1 expression and induced SIRT1 phosphorylation resulting in the augmentation of SIRT1 deacetylase activity. To demonstrate that fluoride exposure initiates autophagy, we characterized the expression of autophagy related genes (Atg); Atg5, Atg7 and Atg8/LC3 and showed that both their transcript and protein levels were significantly increased following fluoride treatment. To confirm that SIRT1 plays a protective role in fluoride toxicity, we used resveratrol (RES) to augment SIRT1 activity in fluoride treated LS8 cells. RES increased autophagy, inhibited apoptosis, and decreased fluoride cytotoxicity. Rats treated with fluoride (0, 50, 100 and 125ppm) in drinking water for 6weeks had significantly elevated expression levels of Sirt1, Atg5, Atg7 and Atg8/LC3 in their maturation stage enamel organs. Increased protein levels of p-SIRT1, ATG5 and ATG8/LC3 were present in fluoride-treated rat maturation stage ameloblasts. Therefore, the SIRT1/autophagy pathway may play a critical role as a protective response to help prevent dental fluorosis.

Modulation of endogenous antioxidant activity by resveratrol and exercise in mouse liver is age dependent

Aging is a multifactorial process in which oxidative damage plays an important role. Resveratrol (RSV) and exercise delay some of the damages occurring during aging and increase life span and health span. We treated mice at different ages with RSV during 6 months and trained them during the last 6 weeks to determine if RSV and exercise induce changes in endogenous antioxidant activities in liver and if their effects depend on the age of the animal at the beginning of the intervention. Aging was accompanied by the increase in oxidative damage in liver especially affecting the glutathione-dependent system. Both RSV and exercise reversed the effect of aging and maintained high activities of glutathione, glutathione peroxidase, and glutathione transferase activities in old animals.

NAD(P)H

quinone acceptor oxidoreductase activity was also increased. Modulation of antioxidant activities was not completely accompanied by changes at the protein level. Whereas glutathione peroxidase 1 protein increased in parallel to the higher activity in old animals,

NAD(P)H

quinone acceptor oxidoreductase protein decreased by RSV although the activity was enhanced. Our results indicate that RSV and exercise revert the effect of aging in liver of old animals maintaining higher antioxidant activities and decreasing oxidative damage. Short-term interventions are enough to produce beneficial effects of RSV or exercise at later ages.

Calorie restriction and resveratrol supplementation prevent age-related DNA and RNA oxidative damage in a non-human primate

Oxidative stress is a key factor in the aging process and in the development of age-related diseases. Because nutritional interventions such as caloric restriction (CR) delay the onset of age-related diseases and increase the lifespan of many species, the impact of a moderate CR was tested on male grey mouse lemur (Microcebus murinus), which have a median survival time of 5.7 years in captivity. The effects of CR on these lemurs were compared with a potential mimetic, resveratrol (RSV), a polyphenol naturally found in grapes. We hypothesized that both CR and RSV impact oxidative DNA and RNA damage compared to standard-fed control (CTL) animals. Adult (3-4 years old) male mouse lemurs were assigned to three dietary groups: a CTL group, a CR group receiving 30% fewer calories than the CTL and a RSV group receiving the CTL diet supplemented with RSV (200 mg·day(-1)·kg(-1)). Oxidative stress was estimated after 3, 9, 15 and 21 months of treatment using the measurement of oxidized nucleosides in urine samples by mass spectrometry. The resting metabolic rate, adjusted for changes in body composition, was also measured to assess the potential relationship between oxygen consumption and oxidative damage markers. This study provides evidence for oxidative stress accumulation with age in grey mouse lemur. Dietary interventions resulted in a short-term increase in oxidative stress levels followed by reduced levels with increasing age. Moreover, in this photoperiod-dependent heterotherm primate, seasonal variations in oxidative stress were observed, which was likely due to a season-dependent, cost-benefit trade-off between torpor use and oxidative stress.

Resolution of the direct interaction with and inhibition of the human GLUT1 hexose transporter by resveratrol from its effect on glucose accumulation

Resveratrol acts as a chemopreventive agent for cancer and as a potential antiobesity and antidiabetic compound, by leading to reduced body fat and improved glucose homeostasis. The exact mechanisms involved in improving hyperglycemic state are not known, but most of the glucose uptake into mammalian cells is facilitated by the GLUT hexose transporters. Resveratrol is structurally similar to isoflavones such as genistein, which inhibit the glucose uptake facilitated by the GLUT1 hexose transporter. Here we examined the direct effects of resveratrol on glucose uptake and accumulation in HL-60 and U-937 leukemic cell lines, which express mainly GLUT1, under conditions that discriminate transport from the intracellular substrate phosphorylation/accumulation. Resveratrol blocks GLUT1-mediated hexose uptake and thereby affects substrate accumulation on these cells. Consequently, we characterized the mechanism involved in inhibition of glucose uptake in human red cells. Resveratrol inhibits glucose exit in human red cells, and the displacement of previously bound cytochalasin B revealed the direct interaction of resveratrol with GLUT1. Resveratrol behaves as a competitive blocker of glucose uptake under zero-trans exit and exchange kinetic assays, but it becomes a mixed noncompetitive blocker when zero-trans entry transport was assayed, suggesting that the binding site for resveratrol lies on the endofacial face of the transporter. We propose that resveratrol interacts directly with the human GLUT1 hexose transporter by binding to an endofacial site and that this interaction inhibits the transport of hexoses across the plasma membrane. This inhibition is distinct from the effect of resveratrol on the intracellular phosphorylation/accumulation of glucose.

Resveratrol and Related Compounds as Antioxidants With an Allosteric Mechanism of Action in Epigenetic Drug Targets

The present review is intended to focus on naturally occurring cytoprotective agents such as resveratrol (trans-3,4’,5-trihydroxystilbene) and other related compounds, probably with similar molecular mechanisms of action and high capacity to find applications in medical fields. Several physiological aspects have been ascribed to resveratrol and similar compounds. Resveratrol, among others, has been recently described as a silent information regulator T1 (SIRT1) activator that increases AMP-activated protein kinase (AMPK) phosphorylation and reduces the oxidative damage biomarkers during aging in laboratory settings. The reports on resveratrol and other SIRT1 activators from various sources are encouraging. The pharmacological strategies for modulation of sirtuins by small molecules through allosteric mechanisms should gain a greater momentum including human research. Resveratrol and resveratrol-like molecules seem to fulfill the requirement of a new horizon in drug research since these molecules cover a growing research means as antioxidants with allosteric mechanism in epigenetic drug targets. However, one should keep in mind the challenges of extrapolation of basic research into clinical results. Overall, the issue of sirtuins in biology and disease provides an insight on therapeutic potentials of sirtuin-based therapeutics and demonstrates the high complexity of drug-targeting these modalities for human applications.

Testosterone plus low-intensity physical training in late life improves functional performance, skeletal muscle mitochondrial biogenesis, and mitochondrial quality control in male mice

Testosterone supplementation increases muscle mass in older men but has not been shown to consistently improve physical function and activity. It has been hypothesized that physical exercise is required to induce the adaptations necessary for translation of testosterone-induced muscle mass gain into functional improvements. However, the effects of testosterone plus low intensity physical exercise training (T/PT) on functional performance and bioenergetics are unknown. In this pilot study, we tested the hypothesis that combined administration of T/PT would improve functional performance and bioenergetics in male mice late in life more than low-intensity physical training alone. 28-month old male mice were randomized to receive T/PT or vehicle plus physical training (V/PT) for 2 months. Compare to V/PT control, administration of T/PT was associated with improvements in muscle mass, grip strength, spontaneous physical movements, and respiratory activity. These changes were correlated with increased mitochondrial DNA copy number and expression of markers for mitochondrial biogenesis. Mice receiving T/PT also displayed increased expression of key elements for mitochondrial quality control, including markers for mitochondrial fission-and-fusion and mitophagy. Concurrently, mice receiving T/PT also displayed increased expression of markers for reduced tissue oxidative damage and improved muscle quality. Conclusion: Testosterone administered with low-intensity physical training improves grip strength, spontaneous movements, and respiratory activity. These functional improvements were associated with increased muscle mitochondrial biogenesis and improved mitochondrial quality control.

Effects of resveratrol on longevity, cognitive ability and aging-related histological markers in the annual fish Nothobranchius guentheri

Aging research was hindered because of the long lifespan of available vertebrates. Annual fishes of Nothobranchius have become a new model organism for aging studies. Resveratrol, a natural plant-derived chemical, prolongs lifespan in many animals. Here we used the wild strain of N. guentheri, which has the mean lifespan of 12months, to detect the effects of resveratrol on the longevity, cognitive ability and aging-related histological markers. Our results showed that the pharmaceutical treatment of resveratrol prolonged the lifespan of N. guentheri but did not affect their body size. Three behavioral assays for cognitive ability and locomotor activity demonstrated that the resveratrol-treated fish exhibited the higher rate of performances than the fish in the control group. Further data indicated that resveratrol not only had the property of protecting N. guentheri from neurodegeneration, but retarded the aging-related histological markers in lipofuscin formation and in the expression of senescence-associated beta-galactosidase activity.

(-)-Epicatechin maintains endurance training adaptation in mice after 14 days of detraining

The purpose of this study was to determine whether (-)-epicatechin (mainly found in cocoa) could attenuate detraining effects in the hindlimb muscles of mice. Thirty-two male mice were randomized into 4 groups: control, trained, trained with 14 d of detraining and vehicle (DT-14-W), and trained with 14 d of detraining and (-)-epicatechin [DT-14-(-)-Epi]. DT-14-(-)-Epi received (-)-epicatechin (1.0 mg/kg 2 ×/d), whereas water was given to the DT-14-W group. The latter 3 groups performed 5 wk of endurance training 5 ×/wk. Hindlimb muscles were harvested, and Western blots, as well as enzyme analyses, were performed. Training significantly increased capillary-to-fiber ratio (≈ 78.8%), cytochrome-c oxidase (≈ 35%), and activity (≈ 144%) compared to controls. These adaptations returned to control levels for the DT-14-W group, whereas the DT-14-(-)-Epi group was able to maintain capillary-to-fiber ratio (≈ 44%), CcO protein expression (≈ 45%), and activity (≈ 108%) above control levels. In addition, the increase in capillarity was related to decreased protein expression of thrombospondin-1, an antiangiogenic regulator. Furthermore, there were no significant differences in endurance capacity between the trained and DT-14-(-)-Epi groups. Our data suggest that (-)-epicatechin may be a suitable compound to maintain exercise-induced improved capillarity and mitochondrial capacity, even when exercise regimens are discontinued.

Chronic resveratrol intake reverses pro-inflammatory cytokine profile and oxidative DNA damage in ageing hybrid mice

Thymic involution and shrinkage of secondary lymphoid organs are leading causes of the deterioration of the T-cell compartment with age. Inflamm-aging, a sustained inflammatory status, has been associated with chronic diseases and shortened longevity. This is the first study to investigate the effect of treating aging hybrid mice with long-term, low-dose resveratrol (RSV) in drinking water by assessing multiple immunological markers and profiles in the immune system. We found that hybrid mice exhibited marked age-related changes in the CD3+CD4+, C3+CD8+, CD4+CD25+, CD4M and CD8M surface markers. RSV reversed surface phenotypes of old mice to that of young mice by maintaining the CD4+ and CD8+ population in splenocytes as well as reducing CD8+CD44+ (CD8M) cells in the aged. RSV also enhanced the CD4+CD25+ population in old mice. Interestingly, pro-inflammatory status in young mice was transiently elevated by RSV but it consequently mitigated the age-dependent increased pro-inflammatory cytokine profile while preserving the anti-inflammatory cytokine condition in the old mice. Age-dependent increase in 8OHdG, an oxidative DNA damage marker was ameliorated by RSV. Immunological-focused microarray gene expression analysis showed that only the CD72 gene was significantly downregulated in the 12-month RSV-treated mice compared to age-matched controls. Our study indicates that RSV even at low physiological relevant levels is able to affect the immune system without causing marked gene expression changes.

What is new for an old molecule? Systematic review and recommendations on the use of resveratrol

Background

Resveratrol is a natural compound suggested to have beneficial health effects. However, people are consuming resveratrol for this reason without having the adequate scientific evidence for its effects in humans. Therefore, scientific valid recommendations concerning the human intake of resveratrol based on available published scientific data are necessary. Such recommendations were formulated after the Resveratrol 2010 conference, held in September 2010 in Helsingør, Denmark.

Methodology

Literature search in databases as PubMed and ISI Web of Science in combination with manual search was used to answer the following five questions: ¹Can resveratrol be recommended in the prevention or treatment of human diseases?; ²Are there observed “side effects” caused by the intake of resveratrol in humans?; ³What is the relevant dose of resveratrol?; ⁴What valid data are available regarding an effect in various species of experimental animals?; ⁵Which relevant (overall) mechanisms of action of resveratrol have been documented?

Conclusions/Significance

The overall conclusion is that the published evidence is not sufficiently strong to justify a recommendation for the administration of resveratrol to humans, beyond the dose which can be obtained from dietary sources. On the other hand, animal data are promising in prevention of various cancer types, coronary heart diseases and diabetes which strongly indicate the need for human clinical trials. Finally, we suggest directions for future research in resveratrol regarding its mechanism of action and its safety and toxicology in human subjects.

Changes in white adipose tissue metabolism induced by resveratrol in rats

Background

A remarkable range of biological functions have been ascribed to resveratrol. Recently, this polyphenol has been shown to have body fat lowering effects. The aim of the present study was to assess some of the potential underlying mechanisms of action which take place in adipose tissue.

Methods

Sixteen male Sprague-Dawley rats were randomly divided into two groups: control and treated with 30 mg resveratrol/kg body weight/d. All rats were fed an obesogenic diet and after six weeks of treatment white adipose tissues were dissected. Lipoprotein lipase activity was assessed by fluorimetry, acetyl-CoA carboxylase by radiometry, and malic enzyme, glucose-6P-dehydrogenase and fatty acid synthase by spectrophotometry. Gene expression levels of acetyl-CoA carboxylase, fatty acid synthase, lipoprotein lipase, hormone-sensitive lipase, adipose triglyceride lipase, PPAR-gamma, SREBP-1c and perilipin were assessed by Real time RT-PCR. The amount of resveratrol metabolites in adipose tissue was measured by chromatography.

Results

There was no difference in the final body weight of the rats; however, adipose tissues were significantly decreased in the resveratrol-treated group. Resveratrol reduced the activity of lipogenic enzymes, as well as that of heparin-releasable lipoprotein lipase. Moreover, a significant reduction was induced by this polyphenol in hormone-sensitive lipase mRNA levels. No significant changes were observed in other genes. Total amount of resveratrol metabolites in adipose tissue was 2.66 ± 0.55 nmol/g tissue.

Conclusions

It can be proposed that the body fat-lowering effect of resveratrol is mediated, at least in part, by a reduction in fatty acid uptake from circulating triacylglycerols and also in de novo lipogenesis.

Drugs, nutrients, and phytoactive principles improving the health span of rodent models of human age-related diseases

Rodents are often the species of choice to examine the effect of drugs on survival and on the progression of specific diseased tissues. This statement is also true for research laboratories working in the field of nutrition and aging. In addition to diets that can reduce the life expectancy of rodents, such as diabetogenic or high-fat diets, genetically modified rodents exhibiting different accelerated age-associated diseases also provide important biologic tools to decipher the impact of drugs, nutrients, or phytoactive compounds on their health and life span. This review covers some of the chemicals believed to decelerate the appearance of age-related diseases in different rodent models. Such chemicals include antioxidants, anti-inflammatory molecules, modulators of metabolic sensors, calorie restriction mimetics, and vegetal polyphenolic compounds that affect mitochondrial functions, cellular proliferation or differentiation as well as cell functionality.

Effect of telmisartan in limiting the cardiotoxic effect of daunorubicin in rats

Objectives

Studies have suggested that angiotensin receptor blockers may exert a protective role towards doxorubicin-induced cardiotoxicity, but they have not been extensively investigated in this area. We therefore investigated whether the co-treatment of telmisartan, an angiotensin (Ang II) type-1 receptor blocker, might offer protection against daunorubicin cardiotoxic properties in rats.

Methods

Daunorubicin was administered at 3 mg/kg/day every other day for 12 days. Telmisartan was administered orally every day for 12 days.

Key findings

Daunorubicin-treated rats showed cardiac toxicity, evidenced by worsening cardiac function, evaluated by haemodynamic status and echocardiography, elevation of malondialdehyde level and a decreased level of total glutathione peroxidase activity in the heart tissue. These changes were reversed by treatment with telmisartan. Furthermore, telmisartan also downregulated matrix metalloproteinase-2 expression, attenuated the increased protein expression of p22phox, p47phox, p67phox, nuclear factor kappa B and Nox4 in heart tissue, and reduced oxidative-stress-induced DNA damage, which was evaluated by the expression of 8-hydroxydeoxyguanosine. Moreover, telmisartan reduced the myocardial apoptosis induced by daunorubicin.

Conclusions

The present study indicates that telmisartan may improve cardiac function by inhibiting the action of Ang II via AT-1R, which reverses oxidative stress and myocardial apoptosis. This suggests a beneficial effect of telmisartan treatment in the prevention of daunorubicin-induced cardiotoxicity.

Dietary polyphenols and obesity

The prevalence of overweight and obesity and their associated metabolic disorders are considered a major threat to the public’s health. While several diet and exercise programs are available for weight loss and prevention of weight regain, progress is often slow and disappointing. Recently, natural bioactive phytochemicals present in foods have been discovered for their potential health benefit effects on the prevention of chronic disorders such as cancer, cardiovascular disease, inflammatory and metabolic diseases including obesity. Polyphenols are a class of naturally-occurring phytochemicals, of which some such as catechins, anthocynines, resveratrol and curcumin have been shown to modulate physiological and molecular pathways that are involved in energy metabolism, adiposity, and obesity. The potential in vivo, beneficial effects of these polyphenols on adiposity and obesity as complementary agents in the up-regulation of energy expenditure have emerged by investigating these compounds in cell cultures, animal models of obesity and in some human clinical and epidemiological studies. In this brief review, the efficacy of the above-named polyphenols and their potential efficacy to modulate obesity and some associated disorders are discussed.

Calorie restriction for optimal cardiovascular aging: the weight of evidence

The epidemic of obesity and overweight is spreading worldwide. Excessive adiposity is associated with a myriad of adverse health outcomes, leading to increased healthcare expenditures and shortened life expectancy. In contrast to overeating, calorie restriction (CR), defined as a reduction in food intake without malnutrition, increases both mean and maximum lifespan in a variety of species by reducing the incidence of several chronic degenerative diseases, including cardiovascular disease. The constellation of health benefits brought about by CR results from biological and physiological changes affecting fundamental processes underlying aging and age-related pathologies. Despite the beneficial properties of CR, it is likely that most people will not engage in such a dietary regimen for the long-term. Supplementation with specific compounds mimicking CR may represent a more feasible means to improve health and prolong life. However, evidence on long-term effectiveness and safety of these compounds is not yet available in humans.

The potential of resveratrol against human gliomas

There is growing interest in dietary phytochemicals as potential cancer chemopreventive agents. Resveratrol (3,4',5-trihydroxy-trans-stilbene), a naturally occurring phytoalexin that is present in grapes, red wine, berries and peanuts, has been studied extensively for its ability to interfere with multistage carcinogenesis. Resveratrol is known to have antioxidant, anti-inflammatory and antiproliferative effects on a variety of cancer cells in vitro and in various animal models. However, the effect(s) of resveratrol in vivo on humans are still controversial. This study discusses current knowledge with regard to the effects of resveratrol in relation to its potential as a chemopreventive and/or chemotherapeutic molecule against human gliomas.

trans-Resveratrol as a neuroprotectant

Epidemiological evidence indicates that nutritionally-derived polyphenols such as resveratrol (RES) have neuroprotective properties. Administration of RES to culture media protects a wide variety of neuronal cell types from stress-induced death. Dietary supplementation of RES can ameliorate neuronal damage and death resulting from both acute and chronic stresses in rodents. The specific molecular mechanisms by which RES acts at the cellular level remain incompletely understood. However, many experimental data indicate that RES reduces or prevents the occurrence of oxidative damage. Here we discuss possible mechanisms by which RES might exert protection against oxidative damage and cell death. Evidence suggesting that RES’s chemical antioxidant potential is not sufficient explanation for its effects is discussed. Putative biological activities, including interactions with estrogen receptors and sirtuins are critically discussed. We provide a synthesis of how RES’s phytoestrogenic properties might mediate the neuronal stress resistance underlying its observed neuroprotective properties.

Antioxidant capacity and oxidative damage determination in synovial fluid of chronically damaged equine metacarpophalangeal joint

In order to determine oxidative stress in equine joints with degenerative processes, we analyzed synovial fluid (SF) antioxidant capacity and the concentration of oxidative damage biomarkers in healthy and chronically damaged metacarpophalangeal joints. SF samples were collected from joints of thirty 2-5 year-old crossbreed male equine, macroscopically classified at post mortem inspection and later histologically confirmed. The antioxidant capacity was determined measuring uric acid and the concentration of sulfhydryl groups and the total radical trapping antioxidant potential (TRAP). The oxidative damage was determined by assessing malondialdehyde (MDA) and carbonyl protein concentration. TRAP was significantly higher (p < 0.05) in the group with chronic damage (CD). The sulfhydryl groups and concentration of uric acid did not show significant difference between the groups (p > 0.05). Although carbonyl concentration did not show significant difference between groups, it was slightly higher in the group with CD (p = 0.05009). Concentration of MDA did not show significant difference (p > 0.05) between groups. The observed significant increase in TRAP in the group with CD could be related to the participation of components other than protein, sulfhydryl groups, or uric acid coming from degenerating joint tissues. These findings could be helpful for a better understanding of the oxidative stress role in equine joints with chronic degenerative process.

Resveratrol in the chemoprevention and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers and lethal diseases in the world. Although the majority of HCC cases occur in developing countries of Asia and Africa, the prevalence of liver cancer has risen considerably in Japan, Western Europe as well as the United States. HCC most commonly develops in patients with chronic liver disease, the etiology of which includes viral hepatitis (B and C), alcohol, obesity, iron overload and dietary carcinogens, including aflatoxins and nitrosamines. The current treatment modalities, including surgical resection and liver transplantation, have been found to be mostly ineffective. Hence, there is an obvious critical need to develop alternative strategies for the chemoprevention and treatment of HCC. Oxidative stress as well as inflammation has been implicated in the development and progression of hepatic neoplasia. Using naturally occurring phytochemicals and dietary compounds endowed with potent antioxidant and antiinflammatory properties is a novel approach to prevent and control HCC. One such compound, resveratrol, present in grapes, berries, peanuts as well as red wine, has emerged as a promising molecule that inhibits carcinogenesis with a pleiotropic mode of action. This review examines the current knowledge on mechanism-based in vitro and in vivo studies on the chemopreventive and chemotherapeutic potential of resveratrol in liver cancer. Pre-clinical and clinical toxicity studies as well as pharmacokinetic data of resveratrol have also been highlighted in this review. Future directions and challenges involved in the use of resveratrol for the prevention and treatment of HCC are also discussed.

Resveratrol attenuates lipopolysaccharide-induced hepatitis in D-galactosamine sensitized rats: role of nitric oxide synthase 2 and heme oxygenase-1

The goal of study was directed to investigate the effects of resveratrol (RES) pretreatment on the enhancing action of D-galactosamine (D-GalN; 800 mg/kg) on lipopolysaccharide (LPS; 0.5 microg/kg) inducing liver failure in rats. Liver function was assessed by determination of plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), alpha-glutathione S-transferase (alpha GST) and bilirubin (BILI). Plasma NO(2)(-) was assessed by NO(2)(-)/NO(3)(-) colorimetric kit. The estimation of nonenzymatic and enzymatic antioxidants (glutathione and catalase) was performed in plasma and liver homogenate. Lipid peroxidation was evaluated by the thiobarbituric acid reacting substances (TBARS) and the conjugated dienes (CD). Morphological examinations using light and electron microscopy were performed. Observations related to pharmacological increases of inducible nitric oxide synthase (NOS-2)/nitric oxide (NO) and inducible heme oxygenase (HO-1) in fulminant hepatic failure and modulation by resveratrol were followed up by real-time reverse transcription PCR (RT-PCR) in liver tissue. In the present study we found that among the mechanisms responsible for the hepatoprotective effect of resveratrol in the LPS/D-GalN liver toxicity model are reduction in NO, downregulation of NOS-2, modification of oxidative stress parameters and modulation of HO-1 which led to overall improvement in hepatotoxic markers and morphology after the hepatic insult.

Is the use of resveratrol in the treatment and prevention of obesity premature?

Obesity is a multi-faceted disease, predisposing sufferers to numerous co-morbidities such as epithelial dysfunction and insulin resistance which ultimately result in CVD. Visceral adipose tissue in particular is associated with inflammation due to the release of pro-inflammatory cytokines by adipocytes. Inflammation seems to be rather central in causing damage to endothelial cells as well as exerting negative effects on glucose metabolism, ultimately leading to insulin resistance. Resveratrol is a naturally occurring phenolic substance which has been found to display anti-inflammatory, vasoprotective and insulin-sensitising effects, among others. The popularity of resveratrol use is escalating in the treatment of various ailments including obesity in adults. The use of the substance in childhood obesity is, however, a worrying factor, as no studies have as yet been performed on adolescent animals and there is evidence of kidney toxicity of resveratrol and its metabolites at intake levels below those currently approved as safe. Another cause for concern is the uncertainty surrounding long-term, low-dose administration of the substance in humans. The supplement should thus not be recommended for use in the prevention and treatment of obesity until conclusive research is established on the safety of long-term usage of resveratrol in both children and adults.