Resveratrol ameliorates aging-related metabolic phenotypes by inhibiting cAMP phosphodiesterases

Red Wine and Health: Approaches to Improve the Phenolic Content During Winemaking

There is ample evidence regarding the health benefits of red wine consumption due to its content of phenolic compounds, as an alternative to improve the state of health and prevent various diseases, being the implementation of procedures that allow a greater extraction and stability of phenolic compounds during the elaboration a key aspect. The first part of this review summarizes some studies, mostly at the preclinical level, on the mechanisms by which phenolic compounds act in the human organism, taking advantage of their antioxidant, anti-inflammatory, antitumor, antithrombotic, antiatherogenic, antimicrobial, antiviral, and other activities. Although the migration of grape components into the must/wine occurs during the winemaking process, the application of new technologies may contribute to increasing the content of phenolic compounds in the finished wine. Some of these technologies have been evaluated on an industrial scale, and in some cases, they have been included in the International Code of Oenological Practice by the International Organization of Vine and Wine (OIV). In this sense, the second part of this review deals with the use of these novel technologies that can increase, or at least maintain, the polyphenol content. For example, in the pre-fermentative stage, phenolic extraction can be increased by treating the berries or must with high pressures, pulsed electric fields (PEF), ultrasound (US), e-beam radiation or ozone. At fermentative level, yeasts with high production of pyranoanthocyanins and/or their precursor molecules, low polyphenol absorption, and low anthocyanin-β-glucosidase activity can be used. Whereas, at the post-fermentative level, aging-on-lees (AOL) can contribute to maintaining polyphenol levels, and therefore transmitting health benefits to the consumer.

Resveratrol ameliorates muscle atrophy in chronic kidney disease via the axis of SIRT1/FoxO1

Chronic kidney disease (CKD) is often associated with muscle atrophy. However, the underlying molecular mechanisms are still not well understood. Here, we treated 5/6-nephrectomized (5/6Nx) rats with resveratrol and found that this treatment greatly improves renal function as evidenced by reduced proteinuria and cystatin C. Moreover, resveratrol ameliorates renal fibrosis by reducing transforming growth factor β (TGF-β) and connective tissue growth factor (CTGF). Meanwhile, muscle atrophy in these 5/6Nx rats was largely attenuated by resveratrol. Immunoprecipitation revealed that SIRT1 physically interacts with FoxO1 in muscle, and this interaction was weakened in 5/6Nx rats. As a consequence, acetylated FoxO1 was increased in muscle of 5/6Nx rats. The application of resveratrol markedly reverses this trend. These data point out that SIRT1 is a key factor for linking renal disease and muscle atrophy. Indeed, both renal dysfunction and muscle atrophy were further aggravated by 5/6Nx in Sirt1^+/- mice. Taken together, our data indicate that SIRT1 plays a pivotal role in muscle atrophy in CKD, and FoxO1 might be a substrate of SIRT1 in this process. Furthermore, resveratrol, together with other agonists of SIRT1, may hold great therapeutic potentials for treating CKD and its related muscle atrophy.

Overview of Nutraceuticals and Cardiometabolic Diseases following Socio-Economic Analysis

The importance of functional food and nutraceutical products to deal with cardiometabolic diseases (CMDs) and metabolic syndrome (MetS) has gained attention in the past few years. The aim of this narrative review is to highlight the potential and effectiveness of nutraceutical in the improvement of CMDs and MetS biomarkers, alongside their burden of disease and economic health expenditure. A science database search was conducted between May and June 2021. A total of 35 studies were included in this paper. We included male and female subjects, children, and adults, in good health or with cardiovascular or metabolic disease. CMDs and MetS have gradually become worldwide health problems, becoming two of the major causes of morbidity and mortality in western countries. The results indicate a positive link between daily consumption of nutraceutical products and an improvement in cardiometabolic and anthropometric biomarkers. In this paper we included a wide range of nutraceutical products. Most of them showed promising data, indicating that nutraceuticals could provide a new therapeutic treatment to reduce prevalence and pharmaceutical expenditures attributed to CMDs and MetS. Unfortunately, there is a huge vacuum of data on nutraceutical usage, savings, and burden reduction. Therefore, further clinical and pharmaco-economic research in the field is highly required.

Resveratrol and neuroprotection: an insight into prospective therapeutic approaches against Alzheimer's disease from bench to bedside

Alzheimer's disease (AD) is the most common cause of dementia and cognitive impairment; yet, there is currently no treatment. A buildup of Aβ, tau protein phosphorylation, oxidative stress, and inflammation in AD is pathogenic. The accumulation of amyloid-beta (Aβ) peptides in these neurocognitive areas is a significant characteristic of the disease. Therefore, inhibiting Aβ peptide aggregation has been proposed as the critical therapeutic approach for AD treatment. Resveratrol has been demonstrated in multiple studies to have a neuroprotective, anti-inflammatory, and antioxidant characteristic and the ability to minimize Aβ peptides aggregation and toxicity in the hippocampus of Alzheimer's patients, stimulating neurogenesis and inhibiting hippocampal degeneration. Furthermore, resveratrol's antioxidant effect promotes neuronal development by activating the silent information regulator-1 (SIRT1), which can protect against the detrimental effects of oxidative stress. Resveratrol-induced SIRT1 activation is becoming more crucial in developing novel therapeutic options for AD and other diseases that have neurodegenerative characteristics. This review highlighted a better knowledge of resveratrol's mechanism of action and its promising therapeutic efficacy in treating AD. We also highlighted the therapeutic potential of resveratrol as an AD therapeutic agent, which is effective against neurodegenerative disorders.

Involvement of the SIRT1/PGC-1α Signaling Pathway in Noise-Induced Hidden Hearing Loss

Objective: To establish an animal model of noise-induced hidden hearing loss (NIHHL), evaluate the dynamic changes in cochlear ribbon synapses and cochlear hair cell morphology, and observe the involvement of the SIRT1/PGC-1α signaling pathway in NIHHL.

Methods: Male guinea pigs were randomly divided into three groups: control group, noise exposure group, and resveratrol treatment group. Each group was divided into five subgroups: the control group and 1 day, 1 week, 2 weeks, and 1 month post noise exposure groups. The experimental groups received noise stimulation at 105 dB SPL for 2 h. Hearing levels were examined by auditory brainstem response (ABR). Ribbon synapses were evaluated by inner ear basilar membrane preparation and immunofluorescence. The cochlear morphology was observed using scanning electron microscopy. Western blotting analysis and immunofluorescence was performed to assess the change of SIRT1/PGC-1α signaling. Levels of superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), ATP and SIRT1 activity were measured using commercial testing kits.

Results: In the noise exposure group, hearing threshold exhibited a temporary threshold shift (TTS), and amplitude of ABR wave I decreased irreversibly. Ribbon synapse density decreased after noise exposure, and the stereocilia were chaotic and then returned to normal. The expression and activity of SIRT1 and PGC-1α protein was lower than that in the control group. SOD, CAT and ATP were also influenced by noise exposure and were lower than those in the control group, but MDA showed no statistical differences compared with the control group. After resveratrol treatment, SIRT1 expression and activity showed a significant increase after noise exposure, compared with the noise exposure group. In parallel, the PGC-1α and antioxidant proteins were also significantly altered after noise exposure, compared with the noise exposure group. The damage to the ribbon synapses and the stereocilia were attenuated by resveratrol as well. More importantly, the auditory function, especially ABR wave I amplitudes, was also promoted in the resveratrol treatment group.

Conclusion: The SIRT1/PGC-1α signaling pathway and oxidative stress are involved in the pathogenesis of NIHHL and could be potential therapeutical targets in the future.

Nutrition, metabolism, and epigenetics: pathways of circadian reprogramming

Food intake profoundly affects systemic physiology. A large body of evidence has indicated a link between food intake and circadian rhythms, and ~24-h cycles are deemed essential for adapting internal homeostasis to the external environment. Circadian rhythms are controlled by the biological clock, a molecular system remarkably conserved throughout evolution. The circadian clock controls the cyclic expression of numerous genes, a regulatory program common to all mammalian cells, which may lead to various metabolic and physiological disturbances if hindered. Although the circadian clock regulates multiple metabolic pathways, metabolic states also provide feedback on the molecular clock. Therefore, a remarkable feature is reprogramming by nutritional challenges, such as a high-fat diet, fasting, ketogenic diet, and caloric restriction. In addition, various factors such as energy balance, histone modifications, and nuclear receptor activity are involved in the remodeling of the clock. Herein, we review the interaction of dietary components with the circadian system and illustrate the relationships linking the molecular clock to metabolism and critical roles in the remodeling process.

Oxidative stress in the pathophysiology of type 2 diabetes and related complications: Current therapeutics strategies and future perspectives

Type 2 diabetes (T2DM) is a persistent metabolic disorder rising rapidly worldwide. It is characterized by pancreatic insulin resistance and β-cell dysfunction. Hyperglycemia induced reactive oxygen species (ROS) production and oxidative stress are correlated with the pathogenesis and progression of this metabolic disease. To counteract the harmful effects of ROS, endogenous antioxidants of the body or exogenous antioxidants neutralise it and maintain bodily homeostasis. Under hyperglycemic conditions, the imbalance between the cellular antioxidant system and ROS production results in oxidative stress, which subsequently results in the development of diabetes. These ROS are produced in the endoplasmic reticulum, phagocytic cells and peroxisomes, with the mitochondrial electron transport chain (ETC) playing a pivotal role. The exacerbated ROS production can directly cause structural and functional modifications in proteins, lipids and nucleic acids. It also modulates several intracellular signaling pathways that lead to insulin resistance and impairment of β-cell function. In addition, the hyperglycemia-induced ROS production contributes to micro- and macro-vascular diabetic complications. Various in-vivo and in-vitro studies have demonstrated the anti-oxidative effects of natural products and their derived bioactive compounds. However, there is conflicting clinical evidence on the beneficial effects of these antioxidant therapies in diabetes prevention. This review article focused on the multifaceted role of oxidative stress caused by ROS overproduction in diabetes and related complications and possible antioxidative therapeutic strategies targeting ROS in this disease.

Histomorphological changes and molecular mechanisms underlying the ameliorative effect of resveratrol on the liver of silver nanoparticles-exposed rats

Exposure to the deleterious effects of silver nanoparticles (AgNPs) is inevitable due to their wide use in medicine and daily life. The current study aimed to delineate the histomorphological changes and the molecular mechanisms underlying the ameliorative effect of Resveratrol (RSV) on rats' livers exposed to AgNPs. Fifty healthy adult male Wistar albino rats were divided into four groups: control, AgNPs-exposed, RSV-treated after AgNPs exposure, and recovery groups. Liver sections were examined by light and electron microscopes, and immunohistochemistry was performed for detection of activated caspase3 and TNFα. Serum ALT and AST, plasma levels of TNFα, IL-6, GSH and SOD were measured. mRNA expression of SIRT1, ADORA3, PAI, CDK1, Nrf2 and NFκB genes in liver tissue homogenate was performed using qRT-PCR. AgNPs-exposure for 28 days caused marked liver tissue damage with trapping in hepatocytes and Kupffer cells, while RSV treatment ameliorated liver ultrastructure and function. Our results clarified the molecular basis of RSV ameliorative effect on liver tissue by significant upregulation of SIRT1-NrF2 signaling pathway with increased levels of the antioxidant GSH and SOD, which represent the antioxidant effect of RSV. Significant upregulation of the protective ADORA3 with downregulation of the proinflammatory PAI-1 and NFκB mRNA expression levels besides decreased plasma levels of TNFα, IL-6 and decreased immunoexpression of TNFα in liver tissue, represent the anti-inflammatory effect of RSV. In addition, decreased immunoexpression of caspase3 and downregulation of CDK1 expression, represent its antiapoptotic effect. In conclusion: RSV ameliorates AgNPs-induced liver damage by antioxidant, anti-inflammatory and antiapoptotic effects.Abbreviations: AgNPs: Silver nanoparticles, RSV: Resveratrol, ROS: Reactive oxygen species, ESR: Electron spin resonance, DMPO: 5,5-Dimethyl-1-pyrroline-N-oxide, H₂O₂: Hydrogen peroxide, SOD: Superoxide dismutase, CAT: Catalase, GPx: Glutathione peroxidase, MPTP: Methyl-4-phenyl-1.2.3.6-tetrahydropyridine, MDA: Malondialdehyde, TNF: Tumor necrosis factor, GSH: Glutathione, Nrf2: Nuclear factor-erythroid 2-related factor 2, ARE: Antioxidant response elements, KEAP1: Kelch-1ike ECH-associated protein l, AMPK: AMP-activated protein kinase, HO-1: Heme oxygenase-1, NF-κB: Nuclear factor-kappa B, SIRT1: Sirtuins, FOXO: Forkhead box, UCP2: Uncoupling protein 2, STZ: Streptozotocin nicotinamide, HSC: hepatic stellate cells, ECM: extracellular matrix.

Drug Candidates for Autoimmune Diseases

Most of the immunosuppressive drugs used in the clinic to prevent organ rejection or to treat autoimmune disorders were originally isolated from fungi or bacteria. Therefore, in addition to plants, these are valuable sources for identification of new potent drugs. Many side effects of established drugs limit their usage and make the identification of new immunosuppressants necessary. In this review, we present a comprehensive overview of natural products with potent anti-inflammatory activities that have been tested successfully in different models of chronic inflammatory autoimmune diseases. Some of these candidates already have passed first clinical trials. The anti-inflammatory potency of these natural products was often comparable to those of established drugs, and they could be used at least in addition to standard therapy to reduce their dose to minimize unwanted side effects. A frequent mode of action is the inhibition of classical inflammatory signaling pathways, such as NF-κB, in combination with downregulation of oxidative stress. A drawback for the therapeutic use of those natural products is their moderate bioavailability, which can be optimized by chemical modifications and, in addition, further safety studies are necessary. Altogether, very interesting candidate compounds exist which have the potential to serve as starting points for the development of new immunosuppressive drugs.

Diet-Induced Metabolic Dysfunction of Hypothalamic Nutrient Sensing in Rodents

A sedentary lifestyle and excessive nutrient intake resulting from the consumption of high-fat and calorie-rich diets are environmental factors contributing to the rapid growth of the current pandemic of type 2 diabetes mellitus (DM2). Fasting hyperglycemia, an established hallmark of DM2, is caused by excessive production of glucose by the liver, resulting in the inability of insulin to suppress endogenous glucose production. To prevent inappropriate elevations of circulating glucose resulting from changes in nutrient availability, mammals rely on complex mechanisms for continuously detecting these changes and to respond to them with metabolic adaptations designed to modulate glucose output. The mediobasal hypothalamus (MBH) is the key center where nutritional cues are detected and appropriate modulatory responses are integrated. However, certain environmental factors may have a negative impact on these adaptive responses. For example, consumption of a diet enriched in saturated fat in rodents resulted in the development of a metabolic defect that attenuated these nutrient sensing mechanisms, rendering the animals prone to developing hyperglycemia. Thus, high-fat feeding leads to a state of “metabolic disability” in which animals’ glucoregulatory responses fail. We postulate that the chronic faltering of the hypothalamic glucoregulatory mechanisms contributes to the development of metabolic disease.

Activation of SIRT-1 Signalling in the Prevention of Bipolar Disorder and Related Neurocomplications: Target Activators and Influences on Neurological Dysfunctions

SIRT-1 (silent mating-type information regulation 2 homolog-1) is a protein found in neuronal nuclei, microglia, and astrocyte cells of the brain. It is sometimes referred to as NAD + -dependent deacetylase (nicotinamide adenine dinucleotide). The activation of sirtuins (SIRT-1-7) has been shown to protect against a wide range of disorders, including neurodegenerative and neuropsychiatric disorders. SIRT-1 has gained considerable interest from these families because of its early link to long-life expansion and calorie restriction involvement. SIRT-1 is necessary for gene silencing, cell cycle regulation, fat and glucose metabolism, oxidative stress, ageing, and memory formation. In this review, we investigate the role of SIRT-1 downregulation in the progression of bipolar disorder (BD) and neurological abnormalities, as well as related neurological alterations such as genetic dysfunction, neurotransmitter imbalance, oxidative stress-induced apoptosis, and mitochondrial dysfunction. BD is a psychiatric disease distinguished by extreme mood fluctuations that range from depressive lows to manic highs. BD is a complicated disorder with numerous clinical signs and neurocomplications that produce significant behavioural problems. SIRT-1 deficiency in the brain has been demonstrated to affect the activity of its transcription factors and molecular changes, including genetic defects. SIRT-1 is now being studied as a potential therapeutic target for a range of brain disorders. A recent study also found that activating SIRT-1 signalling performs a protective effect in avoiding depression and mania-like behaviours. Furthermore, this review investigates the potential mechanisms by which SIRT-1 regulates neuronal transmission and neurogenesis. As a result of our review, we revealed that SIRT-1 activators have neuroprotective potential in BD and related neurological dysfunctions.

Piceatannol Antagonizes Lipolysis by Promoting Autophagy-Lysosome-Dependent Degradation of Lipolytic Protein Clusters in Adipocytes

Overly elevated circulating non-esterified fatty acids (NEFAs) is an emerging health concern of obesity-associated energy disorders. However, methods to reduce circulating NEFAs remain elusive. The present study determined the effect of piceatannol, a naturally occurring stilbene, on adipocyte lipolysis and its underlying mechanism. Differentiated 3T3-L1 adipocytes and brown adipocytes and isolated white adipose tissue were treated with various concentrations of piceatannol for 1.5-hr both in the basal and stimulated lipolysis conditions. Piceatannol significantly inhibited NEFAs and glycerol release with a concomitant reduction of ATGL, CGI-58 and PLIN1 expression in adipocytes. Using a series of inhibitor assays, piceatannol-induced degradation of these proteins was found to be mediated by upregulation of the autophagy-lysosome pathway. Moreover, we demonstrated that piceatannol is capable of stimulating autophagy in vitro. Importantly, piceatannol administration tended to lower fasting-induced serum glycerol levels in healthy mice. Furthermore, piceatannol administration lowered lipolysis, central adiposity and hyperinsulinemia in diet-induced obese mice. Our study provides profound evidence of a novel inhibitory role of piceatannol in lipolysis through autophagy-lysosome-dependent degradation of the key lipolytic proteins in adipocytes. This study offers a mechanistic foundation for investigating the potential of piceatannol-containing foods in reducing lipolysis and its associated metabolic disorders.

Cardiovascular Inflammaging: Mechanisms and Translational Aspects

Aging is one of the major non-reversible risk factors for several chronic diseases, including cancer, type 2 diabetes, dementia, and cardiovascular diseases (CVD), and it is a key cause of multimorbidity, disability, and frailty (decreased physical activity, fatigue, and weight loss). The underlying cellular mechanisms are complex and consist of multifactorial processes, such as telomere shortening, chronic low-grade inflammation, oxidative stress, mitochondrial dysfunction, accumulation of senescent cells, and reduced autophagy. In this review, we focused on the molecular mechanisms and translational aspects of cardiovascular aging-related inflammation, i.e., inflammaging.

Involvement of microRNA modifications in anticancer effects of major polyphenols from green tea, coffee, wine, and curry

Epidemiological studies have shown that consumption of green tea, coffee, wine, and curry may contribute to a reduced risk of various cancers. However, there are some cancer site-specific differences in their effects; for example, the consumption of tea or wine may reduce bladder cancer risk, whereas coffee consumption may increase the risk. Animal and cell-based experiments have been used to elucidate the anticancer mechanisms of these compounds, with reactive oxygen species (ROS)-based mechanisms emerging as likely candidates. Chlorogenic acid (CGA), curcumin (CUR), epigallocatechin gallate (EGCG), and resveratrol (RSV) can act as antioxidants that activate AMP-activated protein kinase (AMPK) to downregulate ROS, and as prooxidants to generate ROS, leading to the downregulation of NF-κB. Polyphenols can modulate miRNA (miR) expression, with these dietary polyphenols shown to downregulate tumor-promoting miR-21. CUR, EGCG, and RSV can upregulate tumor-suppressing miR-16, 34a, 145, and 200c, but downregulate tumor-promoting miR-25a. CGA, EGCG, and RSV downregulate tumor-suppressing miR-20a, 93, and 106b. The effects of miRs may combine with ROS-mediated pathways, enhancing the anticancer effects of these polyphenols. More precise analysis is needed to determine how the different modulations of miRs by polyphenols relate to the cancer site-specific differences found in epidemiological studies related to the consumption of foods containing these polyphenols.

Propolis Ameliorates Alcohol-Induced Depressive Symptoms in C57BL/6J Mice by Regulating Intestinal Mucosal Barrier Function and Inflammatory Reaction

Accumulating evidence points to a critical role of the brain gut axis as an important paradigm for many central nervous system diseases. Recent studies suggest that propolis has obvious neuroprotective properties and functionality in regulating intestinal bacteria flora, hinting at a potential key effect at both terminals of this axis regulation. However, currently no clear evidence confirms the effects of propolis on alcohol-induced depression. Here, we establish an alcoholic depression model with C57BL/6J mice and demonstrate that treatment with propolis protects against alcohol-induced depressive symptoms by behavioral tests. In addition, propolis attenuates the injury of nerve cells in the hippocampal region and restores the serum levels of brain-derived neurotrophic factor (BDNF) and dopamine (DA) in mice with alcohol-induced depression. Pathology and biotin tracer assays show that propolis repairs the intestinal leakage caused by alcohol. Additionally, propolis treatment increases the expression levels of intestinal intercellular tight junctions’ (TJs’) structural proteins Claudin-1, Occludin and zona occludens-1 (ZO-1), as well as the activation state of the liver kinase B1/AMP-activated protein kinase (LKB1/AMPK) signaling pathway, which is closely related to the intestinal permeability. Furthermore, propolis can reduce the levels of pro-inflammatory, lipopolysaccharide (LPS) and fatty-acid-binding protein 2 (FABP2), suggesting the significance of the inflammatory response in alcoholic depression. Collectively, our findings indicate that propolis exerted an improving effect on alcohol-induced depressive symptoms by ameliorating brain gut dysfunction.

Resveratrol Induces the Fasting State and Alters Circadian Metabolism in Hepatocytes

Resveratrol is a nutritional substance that has both metabolic and circadian effects. While some studies indicate a correlation between resveratrol and reduced gluconeogenesis, others propose the opposite. Our aim was to study the metabolic effect of resveratrol around the circadian clock in order to determine more accurately the hepatic signaling pathways involved. AML-12 hepatocytes were treated with resveratrol and clock and metabolic markers were measured around the clock. Resveratrol-treated AML-12 hepatocytes showed reduced ratio of the following key metabolic factors: phosphorylated PP2A to total PP2A (pPP2A/PP2A), pAKT/AKT, pFOXO1/FOXO1 and pAMPK/AMPK, indicating inhibition of AKT and AMPK, but activation of PP2A and FOXO1. In addition, the levels of phosphorylated mTOR were low after resveratrol treatment. The levels of the key gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK) were significantly higher after resveratrol treatment. In accordance with the reduced mTOR activity, the ratio of pBMAL1/BMAL1, the clock transcription factor, also decreased. Bmal1 mRNA oscillated robustly in AML-12 hepatocytes, but resveratrol treatment led to a phase advance and a decrease in its amplitude, similarly to the effect on Srebp1c and Pgc1α mRNA. After resveratrol treatment, daily mRNA levels of Bmal1, Sirt1 and Srebp1c were significantly higher. Resveratrol changes the circadian expression of metabolic and clock genes activating the fasting state and inducing the PP2A-FOXO1-PEPCK pathway.

Emerging Glycation-Based Therapeutics-Glyoxalase 1 Inducers and Glyoxalase 1 Inhibitors

The abnormal accumulation of methylglyoxal (MG) leading to increased glycation of protein and DNA has emerged as an important metabolic stress, dicarbonyl stress, linked to aging, and disease. Increased MG glycation produces inactivation and misfolding of proteins, cell dysfunction, activation of the unfolded protein response, and related low-grade inflammation. Glycation of DNA and the spliceosome contribute to an antiproliferative and apoptotic response of high, cytotoxic levels of MG. Glyoxalase 1 (Glo1) of the glyoxalase system has a major role in the metabolism of MG. Small molecule inducers of Glo1, Glo1 inducers, have been developed to alleviate dicarbonyl stress as a prospective treatment for the prevention and early-stage reversal of type 2 diabetes and prevention of vascular complications of diabetes. The first clinical trial with the Glo1 inducer, trans-resveratrol and hesperetin combination (tRES-HESP)-a randomized, double-blind, placebo-controlled crossover phase 2A study for correction of insulin resistance in overweight and obese subjects, was completed successfully. tRES-HESP corrected insulin resistance, improved dysglycemia, and low-grade inflammation. Cell permeable Glo1 inhibitor prodrugs have been developed to induce severe dicarbonyl stress as a prospective treatment for cancer-particularly for high Glo1 expressing-related multidrug-resistant tumors. The prototype Glo1 inhibitor is prodrug S-p-bromobenzylglutathione cyclopentyl diester (BBGD). It has antitumor activity in vitro and in tumor-bearing mice in vivo. In the National Cancer Institute human tumor cell line screen, BBGD was most active against the glioblastoma SNB-19 cell line. Recently, potent antitumor activity was found in glioblastoma multiforme tumor-bearing mice. High Glo1 expression is a negative survival factor in chemotherapy of breast cancer where adjunct therapy with a Glo1 inhibitor may improve treatment outcomes. BBGD has not yet been evaluated clinically. Glycation by MG now appears to be a pathogenic process that may be pharmacologically manipulated for therapeutic outcomes of potentially important clinical impact.

Hexokinase-2-Linked Glycolytic Overload and Unscheduled Glycolysis-Driver of Insulin Resistance and Development of Vascular Complications of Diabetes

The recent discovery of the glucose-induced stabilization of hexokinase-2 (HK2) to proteolysis in cell dysfunction in model hyperglycemia has revealed a likely key initiating factor contributing to the development of insulin resistance and vascular complications in diabetes. Consequently, the increased flux of glucose metabolism without a change in the expression and activity of glycolytic enzymes produces a wave of increased glycolytic intermediates driving mitochondrial dysfunction and increased reactive oxygen species (ROS) formation, the activation of hexosamine and protein kinase C pathways, the increased formation of methylglyoxal-producing dicarbonyl stress, and the activation of the unfolded protein response. This is called HK2-linked glycolytic overload and unscheduled glycolysis. The conditions required to sustain this are GLUT1 and/or GLUT3 glucose uptake and the expression of HK2. A metabolic biomarker of its occurrence is the abnormally increased deposition of glycogen, which is produced by metabolic channeling when HK2 becomes detached from mitochondria. These conditions and metabolic consequences are found in the vasculature, kidneys, retina, peripheral nerves, and early-stage embryo development in diabetes and likely sustain the development of diabetic vascular complications and embryopathy. In insulin resistance, HK2-linked unscheduled glycolysis may also be established in skeletal muscle and adipose tissue. This may explain the increased glucose disposal by skeletal uptake in the fasting phase in patients with type 2 diabetes mellitus, compared to healthy controls, and the presence of insulin resistance in patients with type 1 diabetes mellitus. Importantly, glyoxalase 1 inducer—trans-resveratrol and hesperetin in combination (tRES-HESP)—corrected HK2-linked glycolytic overload and unscheduled glycolysis and reversed insulin resistance and improved vascular inflammation in overweight and obese subjects in clinical trial. Further studies are now required to evaluate tRES-HESP for the prevention and reversal of early-stage type 2 diabetes and for the treatment of the vascular complications of diabetes.

Resveratrol derivative production by high-pressure treatment: proliferative inhibitory effects on cervical cancer cells

Background: In recent years, functional food components have attracted considerable attention. Resveratrol, a food polyphenol, has been widely studied due to its various physiological activities. Previously, we identified a novel resveratrol derivative, named RK4, in food, which is formed by a chemical reaction involving resveratrol and caffeic acid. Furthermore, it was suggested that high-pressure treatment is an important factor in RK4 production. Objectives: The purpose of this study was to clarify relationships between high-pressure processing and component production and to compare RK4 with the known functional ingredient resveratrol to examine the physiological value of RK4. Through this research, we aimed to develop high-pressure treatment technology that adds new usefulness for food. Methods: Resveratrol and caffeic acid were reacted under high-pressure treatment and in various conditions of concentration and temperature. RK4 levels in the reaction solution were quantitatively analyzed using liquid chromatography-mass spectrometry. In addition, HeLa cervical cancer cells were exposed to RK4 and resveratrol, and survival rates were measured using the methyl thiazolyl tetrazolium (MTT) method after culturing for 24 h. Activation of an apoptosis-inducing marker was detected by western blotting of cells cultured for 48 h after addition of the test compounds. Results: By reacting resveratrol and caffeic acid under high-pressure conditions (~100 MPa), the amount of RK4 produced was significantly increased. It was also found that the reaction temperature and time contributed to this reaction. RK4 exhibited stronger cytotoxicity to HeLa cells than resveratrol. It was also shown that RK4 activated p38, cleaved poly ADP ribose polymerase, and induced apoptosis. Conclusions: RK4 is a valuable component for further research as a novel compound with wider functionality than that of resveratrol. High-pressure treatment may substantially contribute to the production of novel food ingredients. Further elucidation of the relationships between high-pressure treatment and production of new ingredients has promising potential to guide development of new applications in food processing.

Cosmeceutical Potential of Major Tropical and Subtropical Fruit By-Products for a Sustainable Revalorization

The increasing production of tropical fruits followed by their processing results in tons of waste, such as skins or seeds. However, these by-products have been reported to be rich in bioactive compounds (BACs) with excellent properties of interest in the cosmeceutical industry: antioxidant, anti-aging, anti-inflammatory, antimicrobial and photoprotective properties. This review summarizes the tropical fruits most produced worldwide, their bioactive composition and the most important and studied therapeutic properties that their by-products can contribute to skin health, as well as the different approaches for obtaining these compounds using techniques by conventional (Soxhlet, liquid-liquid extraction or maceration) and non-conventional extractions (supercritical fluid extraction (SFE), ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE) and two-phase aqueous system), followed by their identification by HPLC-MS or GC-MS analysis. Moreover, this work encompasses several studies that may prove the effects of seeds and skins from tropical fruits against oxidative stress, hyperpigmentation, acne, aging or UV radiation. Therefore, the investigation of functional components present in tropical fruit by-products under a circular bioeconomy model could be of great interest for the cosmeceutical industry and a very promising option for obtaining new cosmeceutical formulations.

A short-term treatment with resveratrol improves the inflammatory conditions of Middle-aged mice skeletal muscles

Sarcopenia starts around the age of 40, causes the loss of 8% of muscle mass every 10 years, and is accompanied by functional deficit, chronic low-grade inflammation, and can result in several negative health outcomes. Considering the early and gradual onset of sarcopenia, the time window of the potential interventions could be crucial for the exertion of a beneficial effect. We recently showed that the long-term supplementation with Resveratrol contrasts sarcopenia in naturally ageing C57BL/6 mice. Aiming to understand the effects of a short term treatment, we administered intraperitoneally middle aged male mice with 20 mg/kg body weight Resveratrol daily for 5 weeks. Although we could not observe major differences in the histological properties of SKMs, we detected a significant decrease of Cox-2 in RES-treated muscles, confirming the anti-inflammatory action of Resveratrol, and suggesting that its anti-inflammatory action precedes modifications to SKM fibres.

Emerging Role of cAMP/AMPK Signaling

The 5′-Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a natural energy sensor in mammalian cells that plays a key role in cellular and systemic energy homeostasis. At the cellular level, AMPK supports numerous processes required for energy and redox homeostasis, including mitochondrial biogenesis, autophagy, and glucose and lipid metabolism. Thus, understanding the pathways regulating AMPK activity is crucial for developing strategies to treat metabolic disorders. Mounting evidence suggests the presence of a link between cyclic AMP (cAMP) and AMPK signaling. cAMP signaling is known to be activated in circumstances of physiological and metabolic stress due to the release of stress hormones, such as adrenaline and glucagon, which is followed by activation of membrane-bound adenylyl cyclase and elevation of cellular cAMP. Because the majority of physiological stresses are associated with elevated energy consumption, it is not surprising that activation of cAMP signaling may promote AMPK activity. Aside from the physiological role of the cAMP/AMPK axis, numerous reports have suggested its role in several pathologies, including inflammation, ischemia, diabetes, obesity, and aging. Furthermore, novel reports have provided more mechanistic insight into the regulation of the cAMP/AMPK axis. In particular, the role of distinct cAMP microdomains generated by soluble adenylyl cyclase in regulating basal and induced AMPK activity has recently been demonstrated. In the present review, we discuss current advances in the understanding of the regulation of the cAMP/AMPK axis and its role in cellular homeostasis and explore some translational aspects.

Multiple Mechanisms Converging on Transcription Factor EB Activation by the Natural Phenol Pterostilbene

Pterostilbene (Pt) is a potentially beneficial plant phenol. In contrast to many other natural compounds (including the more celebrated resveratrol), Pt concentrations producing significant effects in vitro can also be reached with relative ease in vivo. Here we focus on some of the mechanisms underlying its activity, those involved in the activation of transcription factor EB (TFEB). A set of processes leading to this outcome starts with the generation of ROS, attributed to the interaction of Pt with complex I of the mitochondrial respiratory chain, and spreads to involve Ca²⁺ mobilization from the ER/mitochondria pool, activation of CREB and AMPK, and inhibition of mTORC1. TFEB migration to the nucleus results in the upregulation of autophagy and lysosomal and mitochondrial biogenesis. Cells exposed to several μM levels of Pt experience a mitochondrial crisis, an indication for using low doses in therapeutic or nutraceutical applications. Pt afforded significant functional improvements in a zebrafish embryo model of ColVI-related myopathy, a pathology which also involves defective autophagy. Furthermore, long-term supplementation with Pt reduced body weight gain and increased transcription levels of Ppargc1a and Tfeb in a mouse model of diet-induced obesity. These in vivo findings strengthen the in vitro observations and highlight the therapeutic potential of this natural compound.

FGF1 and insulin control lipolysis by convergent pathways

Inexorable increases in insulin resistance, lipolysis, and hepatic glucose production (HGP) are hallmarks of type 2 diabetes. Previously, we showed that peripheral delivery of exogenous fibroblast growth factor 1 (FGF1) has robust anti-diabetic effects mediated by the adipose FGF receptor (FGFR) 1. However, its mechanism of action is not known. Here, we report that FGF1 acutely lowers HGP by suppressing adipose lipolysis. On a molecular level, FGF1 inhibits the cAMP-protein kinase A axis by activating phosphodiesterase 4D (PDE4D), which separates it mechanistically from the inhibitory actions of insulin via PDE3B. We identify Ser44 as an FGF1-induced regulatory phosphorylation site in PDE4D that is modulated by the feed-fast cycle. These findings establish the FGF1/PDE4 pathway as an alternate regulator of the adipose-HGP axis and identify FGF1 as an unrecognized regulator of fatty acid homeostasis.

Resveratrol attenuates chronic pulmonary embolism-related endothelial cell injury by modulating oxidative stress, inflammation, and autophagy

OBJECTIVES

Due to Pulmonary Artery Endothelial Cell (PAEC) dysfunction, Pulmonary Hypertension (PH) persists even after the Pulmonary Embolism (PE) has been relieved. However, the mechanism behind this remains unclear.

METHOD

Here, the authors incubated Human PAECs (HPAECs) with thrombin to simulate the process of arterial thrombosis.

RESULTS

CCK8 results showed a decrease in the viability of HPAECs after thrombin incubation. In addition, the expression of Tissue Factor (TF), Monocyte Chemoattractant Protein 1 (MCP-1), VCAM-1, ICAM-1, cleaved caspase 3, cleaved caspase 9, and Bax protein were all increased after thrombin incubation, while Bcl-2 was decreased. The effects of 3-MA treatment further suggested that autophagy might mediate the partial protective effects of Resveratrol on HPAECs. To observe the effects of Resveratrol in vivo, the authors established a Chronic Thromboembolic Pulmonary Hypertension (CTEPH) model by repeatedly injecting autologous blood clots into a rat's left jugular vein. The results exhibited that Mean Pulmonary Arterial Pressure (mPAP) and vessel Wall Area/Total Area (WA/TA) ratio were both decreased after Resveratrol treatment. Moreover, Resveratrol could reduce the concentration and activity of TF, vWF, P-selectin, and promote these Superoxide Dismutase (SOD) in plasma. Western blot analysis of inflammation, platelet activation, autophagy, and apoptosis-associated proteins in pulmonary artery tissue validated the results in PHAECs.

CONCLUSIONS

These findings suggested that reduced autophagy, increased oxidative stress, increased platelet activation, and increased inflammation were involved in CTEPH-induced HPAEC dysfunction and the development of PH, while Resveratrol could improve PAEC dysfunction and PH.

Overexpression of PDE4D in mouse liver is sufficient to trigger NAFLD and hypertension in a CD36-TGF-β1 pathway: therapeutic role of roflumilast

Emerging evidence has shown that nonalcoholic fatty liver disease (NAFLD) may be both a consequence and a cause of hypertension. Recent studies have demonstrated that phosphodiesterase 4 (PDE4)-cAMP signaling represents a pathway relevant to the pathophysiology of metabolic disorders. This study aims to investigate the impact and the underlying mechanism of PDE4 in the pathogenesis of NAFLD and its associated hypertension. Here we demonstrated that high-fat-diet (HFD) fed mice developed NAFLD and hypertension, with an associated increase in hepatic PDE4D expression, which can be prevented and even reversed by PDE4 inhibitor roflumilast. Furthermore, we demonstrated that hepatic overexpression of PDE4D drove significant hepatic steatosis and elevation of blood pressure. Mechanistically, PDE4D activated fatty acid translocase CD36 signaling which facilitates hepatic lipid deposition, resulting in TGF-β1 production by hepatocytes and excessive TGF-β1 signaling in vessels and consequent hypertension. Specific silencing of TGF-β1 in hepatocytes by siRNA using poly (β-amino ester) nanoparticles significantly normalized hepatic PDE4D overexpression-activated TGF-β1 signaling in vessels and hypertension. Together, the conclusions indicated that PDE4D plays an important role in the pathogenesis of NAFLD and associated hypertension via activation of CD36-TGF-β1 signaling in the liver. PDE4 inhibitor such as roflumilast, which is clinically approved for chronic obstructive pulmonary disease (COPD) treatment, has the potential to be used as a preventive or therapeutic drug against NAFLD and associated hypertension in the future.

Effect of resveratrol on superovulation in mice

Oocyte quality is one of the key factors affecting the outcome of ART. Therefore, how to improve oocyte quality has become an urgent problem in the field of ART. In this study we evaluated the effect of resveratrol (RSV), added during the process of superovulation, on embryonic development in mice. The results showed that the blastocyst rate was significantly higher in the RSV treated group than in the control group when oocytes were parthenogenetically activated in vitro (61.67 vs 41.51%, P = 0.032). In the naturally fertilized oocytes group, the rates of cleavage and blastocyst were significantly higher in the RSV treatment group than in the control group (74.47% vs 60.98%, P = 0.035; 96.19% vs 70.00%, P = 0.000, respectively). For the aged mice, the average number of oocytes, the rates of cleavage and blastocyst were also significantly higher in RSV treated groups than in the control group (19.47 ± 5.98 vs 10.30 ± 4.82, P = 0.028; 69.03 vs 50.75%, P = 0.014; 64.10% vs 44.12%, P = 0.049, respectively). Mitochondrial membrane potential and mtDNA copy number in oocytes were significantly increased after RSV treatment in both the young and aged populations. The expression of mitochondrial biogenesis related genes was significantly upregulated in cumulus cells of young and aged mice following RSV treatment. Our data suggest that supplementation of RSV during superovulation improves oocytes quality in young and aged mice, increases the number of oocytes retrieved from aged mice, and improves oocytes mitochondrial function.

Therapeutic Effects of Resveratrol on Nonalcoholic Fatty Liver Disease Through Inflammatory, Oxidative Stress, Metabolic, and Epigenetic Modifications

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing around the world, in association with the progressive elevation in overweight and obesity. The accumulation of lipids in NAFLD patients contributes to the development of insulin resistance, inflammation and oxidative stress in hepatocytes, and alteration of blood lipids and glycaemia. There are currently no effective pharmacological therapies for NAFLD, although lifestyle and dietary modifications targeting weight reduction are among the prevailing alternative approaches. For this reason, new approaches should be investigated. The natural polyphenol resveratrol represents a potential new treatment for management of NAFLD due to anti-inflammatory and antioxidant properties. Although preclinical trials have demonstrated promising results of resveratrol against NALFD, the lack of conclusive results creates the need for more trials with larger numbers of patients, longer time courses, and standardized protocols.

Fabrication of Resveratrol-Loaded Scaffolds and Their Application for Delaying Cell Senescence In Vitro

In this research, resveratrol (RSV)-loaded scaffolds have been prepared to control the release of resveratrol and used to delay hepatic stellate cell (HSC) senescence in vitro. The functional carboxyl group-COOH is first introduced to the surface of poly(ε-caprolactone/d,l-lactide) (P(CL-DLLA)) under the coadministration of ultra-violet (UV) treatment and photo initiator and then resveratrol are conjugated onto the surface of the modified scaffolds through esterification. The characterization of the structure of RSV-AA-P(CL-DLLA) shows that resveratrol has been successfully conjugated onto the modified surface. Cell growth exhibits a higher level of cell viability and much more obvious agglomeration on the surface of the synthetic RSV-AA-P(CL-DLLA). Meanwhile the activity of senescence-associated β-galactosidase (SA-β-gal) and reactive oxygen species (ROS) is downgulated for cells on RSV-AA-P(CL-DLLA), which suggests that cell senescence is delayed on RSV-AA-P(CL-DLLA). And then it is attested that cells have a lower level of p53 but SIRT1 expression is upregulated on RSV-AA-P(CL-DLLA), which might be related to resveratrol release from RSV-AA-P(CL-DLLA). It also suggested cell senescence on RSV-AA-P(CL-DLLA) has been regulated by p53 and the SIRT1 signaling pathway. In all, the present study shows that RSV-AA-P(CL-DLLA) can be successfully prepared to promote cell growth and delay cell senescence and could be used for cell-based therapy in tissue engineering.

Biochemical Investigation of Therapeutic Potential of Resveratrol Against Arsenic Intoxication

Arsenic has been reported to cause damaging effects on different body organs. This study was designed to evaluate the protective effect of resveratrol (RSV) against arsenic trioxide (ATO)–induced intoxication in experimental animals. Twenty-four Wistar rats were allocated in 4 groups: group 1: control group, received normal diet; group 2: received ATO (3 mg/kg); group 3: received RSV (8 mg/kg) 30 minutes before administration of ATO; and group 4: received ascorbic acid (25 mg/kg) 30 minutes before administration of ATO. Treatments were given to experimental rats daily for consecutive 8 days. At the end of experimental period, bioaccumulation of arsenic in liver and kidney was assessed by hydride generation-atomic absorption spectrophotometer to investigate the association of arsenic accumulation with histological aberrations. Following parameters were also investigated: serum biochemical profile (alanine aminotransferase, aspartate transaminase, alkaline phosphatase, blood urea nitrogen, and creatinine) for evaluation of liver and kidney functions and lipid peroxidation and oxidative stress (malondialdehyde, glutathione, superoxide dismutase, catalase, and glutathione peroxidase) in tissue homogenates of liver and kidney for estimation of oxidative status. The findings of this study indicate that RSV remarkably ameliorated the hepatic and renal toxicity in arsenic-exposed rat model due to its strong antioxidant potential.

The anti-depressant effects of a novel PDE4 inhibitor derived from resveratrol

CONTEXT

Resveratrol has shown anti-stress and anti-depressant-like abilities involved in inhibiting phosphodiesterase-4 (PDE4) enzyme. However, its application is limited due to its low efficacy, bioavailability and selectivity.

OBJECTIVE

This study synthesized a new resveratrol derivative RES003 and evaluated its PDE4 inhibitory and anti-depressant-like activities in vitro and in vivo, respectively.

MATERIALS AND METHODS

PDEs inhibitory activities were evaluated by radioactive tracer method. Anti-depressant-like activities of novel resveratrol analogue (RES003) at doses of 2.5, 5.0 and 10 mg/kg was investigated by sugar water consumption and forced swimming tests using male ICR mice under chronic unpredictable stress procedure for 10 days. A total of 84 mice were randomly distributed into seven groups (n = 12). Drugs and vehicle were administered (intra-gastric or intra-peritoneal) once a day from the first to the last day. The molecular mechanisms were identified by western blot.

RESULTS

RES003 showed more potent PDE4 inhibitory activity (half maximal inhibitory concentration (IC₅₀), 0.87 μM) and better selectivity than resveratrol (IC₅₀, 18.8 μM). RES003 could significantly increase the consumption of sugar water (p < 0.01) and immobility time (p < 0.01) compared to vehicle-treated stressed groups at doses of 5 and 10 mg/kg. Furthermore, RES003 could significantly increase the levels of cyclic adenosine monophosphate response element binding protein phosphorylation (10 mg/kg, p < 0.05) and brain-derived neurotrophic factor (BDNF) expression (5 and 10 mg/kg, p < 0.05 and 0.01) in mouse brain.

DISCUSSION AND CONCLUSIONS

RES003 could ameliorate chronic stress induced depression-like behaviours through inhibition of PDE4 and activation of cAMP-triggered phosphorylation of cAMP response element binding protein/BDNF signalling pathway. Consequently, RES003 is a promising lead compound for the treatment of depression.

Resveratrol-Induced Signal Transduction in Wound Healing

Resveratrol is a well-known polyphenol that harbors various health benefits. Besides its well-known anti-oxidative potential, resveratrol exerts anti-inflammatory, pro-angiogenic, and cell-protective effects. It seems to be a promising adjuvant for various medical indications, such as cancer, vascular, and neurodegenerative diseases. Additionally, resveratrol was shown to display beneficial effects on the human skin. The polyphenol is discussed to be a feasible treatment approach to accelerate wound healing and prevent the development of chronic wounds without the drawback of systemic side effects. Despite resveratrol's increasing popularity, its molecular mechanisms of action are still poorly understood. To take full advantage of resveratrol's therapeutic potential, a profound knowledge of its interactions with its targets is needed. Therefore, this review highlights the resveratrol-induced molecular pathways with particular focus on the most relevant variables in wound healing, namely inflammation, oxidative stress, autophagy, collagen proliferation and angiogenesis.

Mediterranean diet and cognitive function: From methodology to mechanisms of action

The traditional Mediterranean diet (MedDiet), rich in minimally processed plant foods and fish, has been widely recognized to be one of the healthiest diets. Data from multiple randomized clinical trials have demonstrated its powerful effect against oxidative stress, inflammation and the development and progression of cardiovascular disease, type 2 diabetes, and other metabolic conditions that play a crucial role in the pathogenesis of neurodegenerative diseases. The protecting effects of the MedDiet against cognitive decline have been investigated in several observational and experimental studies. Data from observational studies suggest that the MedDiet may represent an effective dietary strategy for the early prevention of dementia, although these findings require further substantiation in clinical trials which have so far produced inconclusive results. Moreover, as we discuss in this review, accumulating data emphasizes the importance of: 1) maintaining an optimal nutritional and metabolic status for the promotion of healthy cognitive aging, and 2) implementing cognition-sparing dietary and lifestyle interventions during early time-sensitive windows before the pathological cascades turn into an irreversible state. In summary, components of the MedDiet pattern, such as essential fatty acids, polyphenols and vitamins, have been associated with reduced oxidative stress and the current evidence from observational studies seems to assign to the MedDiet a beneficial role in promoting brain health; however, results from clinical trials have been inconsistent. While we advocate for longitudinal analyses and for larger and longer clinical trials to be conducted, we assert our interim support to the use of the MedDiet as a protective dietary intervention for cognitive function based on its proven cardiovascular and metabolic benefits.

The sex steroid precursor dehydroepiandrosterone prevents nonalcoholic steatohepatitis by activating the AMPK pathway mediated by GPR30

The prevalence of nonalcoholic steatohepatitis (NASH) caused by estrogen deficiency increased sharply in recent decades and has become a major threat to liver health in postmenopausal women. There is no effective strategy to control the incidence and development of NASH. Dehydroepiandrosterone (DHEA) is the most abundant circulating steroid with immune and metabolic regulatory properties, and its level markedly declines with increasing age in humans. Importantly, DHEA can convert into active sex hormones depending on the local needs of target tissues with little diffusion, which serves to avoid systemic side-effects from other tissues' exposure to estrogen. Here, we found that DHEA prevented the incidence and development of NASH, which is characterized by the reduction of hepatic steatosis, fibrosis, and inflammation in female mice fed with high-fat/high-cholesterol diets and effectively attenuated lipid accumulation, inflammatory response, and oxidative stress in palmitic acid-challenged hepatocytes. Mechanistically, in vitro and in vivo studies showed that the anti-NASH function of DHEA depended on its biotransformation into estrogen rather than androgen, and which up-regulates the expression of G protein-coupled estrogen receptor (GPR30), a non-classical estrogen receptor. The activation of GPR30-mediated AMP-activated protein kinase signaling is a necessary prerequisite for the alleviative effects of DHEA on NASH. Collectively, our data show the mechanisms of DHEA treatment and its effects on NASH that were previously overlooked; the data also show that GPR30 can be used as a target for treating lipid metabolism disorders and related diseases, such as NASH. Furthermore, these findings have the potential to help researchers develop new strategies for preventing NASH in postmenopausal women.

Human Sirtuin Regulators: The "Success" Stories

The human sirtuins are a group of NAD⁺-dependent protein deacylases. They “erase” acyl modifications from lysine residues in various cellular targets including histones, transcription factors, and metabolic enzymes. Through these far-reaching activities, sirtuins regulate a diverse array of biological processes ranging from gene transcription to energy metabolism. Human sirtuins have been intensely pursued by both academia and industry as therapeutic targets for a broad spectrum of diseases such as cancer, neurodegenerative diseases, and metabolic disorders. The last two decades have witnessed a flood of small molecule sirtuin regulators. However, there remain relatively few compounds targeting human sirtuins in clinical development. This reflects the inherent issues concerning the development of isoform-selective and potent molecules with good drug-like properties. In this article, small molecule sirtuin regulators that have advanced into clinical trials will be discussed in details as “successful” examples for future drug development. Special attention is given to the discovery of these compounds, the mechanism of action, pharmacokinetics analysis, formulation, as well as the clinical outcomes observed in the trials.

Benefits of the Phytoestrogen Resveratrol for Perimenopausal Women

Endometriosis, characterized by macroscopic lesions in the ovaries, is a serious problem for women who desire conception. Damage to the ovarian cortex is inevitable when lesions are removed via surgery, which finally decreases the ovarian reserve, thereby accelerating the transition to the menopausal state. Soon after cessation of ovarian function, in addition to climacteric symptoms, dyslipidemia and osteopenia are known to occur in women aged >50 years. Epidemiologically, there are sex-related differences in the frequencies of dyslipidemia, hypertension, and osteoporosis. Females are more susceptible to these diseases, prevention of which is important for healthy life expectancy. Dyslipidemia and hypertension are associated with the progression of arteriosclerosis, and arteriosclerotic changes in the large and middle blood vessels are one of the main causes of myocardial and cerebral infarctions. Osteoporosis is associated with aberrant fractures in the spine and hip, which may confine the patients to the bed for long durations. Bone resorption is accelerated by activated osteoclasts, and rapid bone remodeling reduces bone mineral density. Resveratrol, a plant-derived molecule that promotes the function and expression of the sirtuin, SIRT1, has been attracting attention, and many reports have shown that resveratrol might exert cardiovascular protective effects. Preclinical reports also indicate that it can prevent bone loss and endometriosis. In this review, I have described the possible protective effects of resveratrol against arteriosclerosis, osteoporosis, and endometriosis because of its wide-ranging functions, including anti-inflammatory and antioxidative stress functions. As ovarian function inevitably declines after 40 years, intake of resveratrol can be beneficial for women with endometriosis aged <40 years.

Supplementing media with NAD+ precursors enhances the in vitro maturation of porcine oocytes

In vitro maturation (IVM) is an important reproductive technology used to produce embryos in vitro. However, the developmental potential of oocytes sourced for IVM is markedly lower than those matured in vivo. Previously, NAD+-elevating treatments have improved oocyte quality and embryo development in cattle and mice, suggesting that NAD+ is important during oocyte maturation. The aim of this study was to examine the effects of nicotinic acid (NA), nicotinamide (NAM) and nicotinamide mononucleotide (NMN) on oocyte maturation and subsequent embryo development. Porcine oocytes from small antral follicles were matured for 44 h in a defined maturation medium supplemented with NA, NAM and resveratrol or NMN. Mature oocytes were artificially activated and presumptive zygotes cultured for 7 days. Additionally, oocytes were matured without treatment then cultured for 7 days with NMN. Supplementing the IVM medium with NA improved maturation and blastocyst formation while NAM supplementation improved cleavage rates compared with untreated controls. Supplementing the IVM or embryo culture media with NMN had no effect on maturation or embryo development. The results show that supplementing the maturation medium with NA and NAM improved maturation and developmental potential of porcine oocytes.

Sirtuin 1 in Endothelial Dysfunction and Cardiovascular Aging

Sirtuin 1 (SIRT1) is a histone deacetylase belonging to the family of Sirtuins, a class of nicotinamide adenine dinucleotide (NAD+)-dependent enzymes with multiple metabolic functions. SIRT1 localizes in the nucleus and cytoplasm, and is implicated in the regulation of cell survival in response to several stimuli, including metabolic ones. The expression of SIRT1 is associated with lifespan and is reduced with aging both in animal models and in humans, where the lack of SIRT1 is regarded as a potential mediator of age-related cardiovascular diseases. In this review, we will summarize the extensive evidence linking SIRT1 functional and quantitative defects to cellular senescence and aging, with particular regard to their role in determining endothelial dysfunction and consequent cardiovascular diseases. Ultimately, we outline the translational perspectives for this topic, in order to highlight the missing evidence and the future research steps.

Rodent diet aids and the fallacy of caloric restriction

Understanding the molecular mechanisms of normal aging is a prerequisite to significantly improving human health span. Caloric restriction (CR) can delay aging and has served as a yardstick to evaluate interventions extending life span. However, mice given unlimited access to food suffer severe obesity. Health gains from CR depend on control mice being sufficiently overweight and less obese mouse strains benefit far less from CR. Pharmacologic interventions that increase life span, including resveratrol, rapamycin, nicotinamide mononucleotide and metformin, also reduce body weight. In primates, CR does not delay aging unless the control group is eating enough to suffer from obesity-related disease. Human survival is optimal at a body mass index achievable without CR, and the above interventions are merely diet aids that shouldn't slow aging in healthy weight individuals. CR in humans of optimal weight can safely be declared useless, since there is overwhelming evidence that hunger, underweight and starvation reduce fitness, survival, and quality of life. Against an obese control, CR does, however, truly delay aging through a mechanism laid out in the following tumor suppression theory of aging.

A Quantitative Proteomics Approach to Gain Insight into NRF2-KEAP1 Skeletal Muscle System and Its Cysteine Redox Regulation

Mammalian skeletal muscle (SkM) tissue engages the Nrf2-Keap1-dependent antioxidant defense mechanism to respond adaptively to stress. Redox homeostasis mediated by the reversible modification of selective cysteines is the prevalent mode of regulation. The protein targets of SkM redox regulation are largely unknown. We previously reported the proteomic profiles of soleus (Sol) and extensor digitorum longus (EDL) with Nrf2 or Keap1 gene deletion, using SkM-specific Nrf2 or Keap1 knockout models; iMS-Nrf2flox/flox; and iMS-Keap1flox/flox. Here, we employed these two animal models to understand the global expression profile of red tibialis anterior (RTA) using a label free approach and its redox proteomics using iodoacetyl tandem mass tag (iodoTMTTM)-labeled cysteine quantitation. We quantified 298 proteins that were significantly altered globally in the RTA with Nrf2 deficiency but only 21 proteins in the Keap1 KO samples. These proteins are involved in four intracellular signaling pathways: sirtuin signaling, Nrf2 mediated oxidative stress response, oxidative phosphorylation, and mitochondrion dysfunction. Moreover, we identified and quantified the cysteine redox peptides of 34 proteins, which are associated with mitochondrial oxidative phosphorylation, energy metabolism, and extracellular matrix. Our findings suggest that Nrf2-deficient RTA is implicated in metabolic myopathy, mitochondrial disorders, and motor dysfunction, possibly due to an enhanced oxidative modification of the structure and functional proteins in skeletal myocytes.

Resveratrol Treatment in Human Parkin-Mutant Fibroblasts Modulates cAMP and Calcium Homeostasis Regulating the Expression of Mitochondria-Associated Membranes Resident Proteins

Parkin plays an important role in ensuring efficient mitochondrial function and calcium homeostasis. Parkin-mutant human fibroblasts, with defective oxidative phosphorylation activity, showed high basal cAMP level likely ascribed to increased activity/expression of soluble adenylyl cyclase and/or low expression/activity of the phosphodiesterase isoform 4 and to a higher Ca²⁺ level. Overall, these findings support the existence, in parkin-mutant fibroblasts, of an abnormal Ca²⁺ and cAMP homeostasis in mitochondria. In our previous studies resveratrol treatment of parkin-mutant fibroblasts induced a partial rescue of mitochondrial functions associated with stimulation of the AMPK/SIRT1/PGC-1α pathway. In this study we provide additional evidence of the potential beneficial effects of resveratrol inducing an increase in the pre-existing high Ca²⁺ level and remodulation of the cAMP homeostasis in parkin-mutant fibroblasts. Consistently, we report in these fibroblasts higher expression of proteins implicated in the tethering of ER and mitochondrial contact sites along with their renormalization after resveratrol treatment. On this basis we hypothesize that resveratrol-mediated enhancement of the Ca²⁺ level, fine-tuned by the ER-mitochondria Ca²⁺ crosstalk, might modulate the pAMPK/AMPK pathway in parkin-mutant fibroblasts.

The protective effect of the PDE-4 inhibitor rolipram on intracerebral haemorrhage is associated with the cAMP/AMPK/SIRT1 pathway

Rolipram specifically inhibits phosphodiesterase (PDE) 4, thereby preventing inactivation of the intracellular second messenger cyclic adenosine monophosphate (cAMP). Rolipram has been shown to play a neuroprotective role in some central nervous system (CNS) diseases. However, the role of PDE4 and the potential protective effect of rolipram on the pathophysiological process of intracerebral haemorrhage (ICH) are still not entirely clear. In this study, a mouse model of ICH was established by the collagenase method. Rolipram reduced brain oedema, blood–brain barrier (BBB) leakage, neuronal apoptosis and inflammatory cytokine release and improved neurological function in our mouse model of ICH. Moreover, rolipram increased the levels of cAMP and silent information regulator 1 (SIRT1) and upregulated the phosphorylation of AMP-activated protein kinase (AMPK). Furthermore, these effects of rolipram could be reversed by the SIRT1 inhibitor sirtinol. In conclusion, rolipram can play a neuroprotective role in the pathological process of ICH by activating the cAMP/AMPK/SIRT1 pathway.

Lockdown of mitochondrial Ca2+ extrusion and subsequent resveratrol treatment kill HeLa cells by Ca2+ overload

Anticancer effect of resveratrol and the role of sodium/lithium/calcium exchanger in context with calcium ions are studied in human cervical cancer cell line. This therapeutic approach using siNCLX mediated gene silencing and drug therapy with resveratrol indicates the disruption of calcium homeostasis, increase in caspase (-3, 8, 9) mRNA expressions and DNA damage leading to apoptotic cell death. Monitoring the intracellular Ca2+ changes using fluo-4AM indicates highest rise in [Ca2+] level in sodium/lithium/calcium exchanger silenced group with five different stages, that is distinguishable based on the fluorescence intensity. In resveratrol treated and siNCLX + resveratrol treated groups no such cell staging differences were observed, despite uniform Ca2+ rise followed by decrease in the intensity. Integrating RNAi gene silencing of sodium/lithium/calcium exchanger with resveratrol can form the most interesting, efficient and promising therapeutic strategy in the treatment of cancer.

N-Acetyl Cysteine Ameliorates High-Fat Diet-Induced Nonalcoholic Fatty Liver Disease and Intracellular Triglyceride Accumulation by Preserving Mitochondrial Function

Rationale: Nonalcoholic fatty liver disease (NAFLD) is a kind of metabolic disease characterized by liver steatosis. Excessive reactive oxygen species (ROS) originating from dysfunctional mitochondria is the major pathophysiological contributor in the development of NAFLD and is thought to be a promising therapeutic target. A few reports demonstrate the antioxidative treatments for NAFLD.

Methods: Male C57 mice were fed on a normal chow diet (ND) or high-fat diet (HFD) for 8 weeks. PBS or N-acetyl cysteine (NAC) was gavaged to mice. LO2 human liver cell line treated with palmitic acid (PA) was applied as a cellular model. Western blot, immunofluorescence, biochemistry assay, and pathological staining were used to investigate the mechanism of suppressing lipid accumulation of NAC.

Results: NAC treatment was able to prevent HFD-induced NAFLD, as evidenced by less hepatic triglyceride accumulation and lipid droplet formation compared with that of mice in the HFD group. NAC could preserve mitochondrial function by inhibiting excessive mitophagy and promoting mitochondria biogenesis to prevent ROS production. NAC also activated Sirt1 and preserved its protein level and subsequently promoted mitochondria biogenesis via deacetylating PGC1a.

Conclusion: We demonstrated that NAC may be an effective drug to treat NAFLD, which was related to its antioxidative and mitochondrial protective effect.

Targeting Wnt signaling pathway by polyphenols: implication for aging and age-related diseases

Age is an important risk factor for different diseases. The same mechanisms that promote aging are involved in the development and progression of age-associated diseases. Polyphenols are organic compounds found in fruits and vegetables. Due to their beneficial properties (e.g. antioxidant and anti-inflammatory), polyphenols have been extensively used for treating chronic diseases. To exert their functions, polyphenols target various molecular mechanisms and signaling pathways, such as mTOR, NF-κB, and Wnt/β-catenin. Wnt signaling is a critical pathway for developmental processes. Besides, dysregulation of this signaling pathway has been observed in various diseases. Several investigations have been conducted on Wnt inhibitors at pre-clinical stages, showing promising results. Herein, we review the studies dealing with the role of polyphenols in targeting the Wnt signaling pathways in aging processes and age-associated diseases, including cancer, diabetes, Alzheimer's disease, osteoporosis, and Parkinson's disease.

Beneficial Effects of Resveratrol in Mouse Gastrocnemius: A Hint to Muscle Phenotype and Proteolysis

We hypothesized that the phenolic compound resveratrol mitigates muscle protein degradation and loss and improves muscle fiber cross-sectional area (CSA) in gastrocnemius of mice exposed to unloading (7dI). In gastrocnemius of mice (female C57BL/6J, 10 weeks) exposed to a seven-day period of hindlimb immobilization with/without resveratrol treatment, markers of muscle proteolysis (tyrosine release, systemic troponin-I), atrophy signaling pathways, and muscle phenotypic features and function were analyzed. In gastrocnemius of unloaded mice treated with resveratrol, body and muscle weight and function were attenuated, whereas muscle proteolysis (tyrosine release), proteolytic and apoptotic markers, atrophy signaling pathways, and myofiber CSA significantly improved. Resveratrol treatment of mice exposed to a seven-day period of unloading prevented body and muscle weight and limb strength loss, while an improvement in muscle proteolysis, proteolytic markers, atrophy signaling pathways, apoptosis, and muscle fiber CSA was observed in the gastrocnemius muscle. These findings may have potential therapeutic implications in the management of disuse muscle atrophy in clinical settings.