Resveratrol induces autophagy by directly inhibiting mTOR through ATP competition

Targeting of AMPK/MTOR signaling in the management of atherosclerosis: Outmost leveraging

Atherosclerosis (AS) is a chronic vascular disorder that is characterized by the thickening and narrowing of arteries due to the development of atherosclerotic plaques. The traditional risk factors involved in AS are obesity, type 2 diabetes (T2D), dyslipidemia, hypertension, and smoking. Furthermore, non-traditional risk factors for AS, such as inflammation, sleep disturbances, physical inactivity, air pollution, and alterations of gut microbiota, gained attention in relation to the pathogenesis of AS. Interestingly, the pathogenesis of AS, is complex and related to different abnormalities of cellular and sub-cellular signaling pathways. It has been illustrated that AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (MTOR) pathways are involved in AS pathogenesis. Mounting evidence indicated that AMPK plays a critical role in attenuating the development of AS by activating autophagy, which is impaired during atherogenesis. AMPK has a vasculoprotective effect by reducing lipid accumulation, inflammatory cell proliferation, and the release of pro-inflammatory cytokines, as well as decreasing inflammatory cell adhesion to the vascular endothelium. AMPK activation by metformin inhibits the migration of vascular smooth muscle cells (VSMCs) and AS development. However, the MTOR pathway contributes to AS by inhibiting autophagy, highlighting autophagy as a crucial link between the AMPK and MTOR pathways in AS pathogenesis. The MTOR is a key inducer of endothelial dysfunction and is involved in the development of AS. Therefore, both the AMPK and MTOR pathways play a crucial role in the pathogenesis of AS. However, the exact role of AMPK and MTOR pathways in the pathogenesis of AS is not fully clarified. Therefore, this review aims to discuss the potential role of the AMPK/MTOR signaling pathway in AS, and how AMPK activators and MTOR inhibitors influence the development and progression of AS. In conclusion, AMPK activators and MTOR inhibitors have vasculoprotective effects against the development and progression of AS.

Substituents introduction of methyl and methoxy functional groups on resveratrol stabilizes mTOR binding for autophagic cell death induction

The regulation of the mammalian target of rapamycin (mTOR) protein by cancer cells can lead to uncontrol of cancer cell growth and cancer therapy resistance. The drug discovery of the anticancer agent 5-(3-hydroxy-4-methoxyphenethyl)-2-methoxy-3-methylphenol (SM-3), a derivative of resveratrol by substituting a methyl group at the hydroxy group of ring A and adding a methoxy group at the para position of ring B, shows promising potential for targeting autophagy to induce cell death and suppress cancer stem cells (CSCs) through the inhibition of the mTOR protein. In human lung cancer cells, SM-3 showed greater efficacy, with lower IC50 values of 72.74 ± 0.13, 67.66 ± 0.10, and 43.24 ± 0.11 µM in A549, H292, and H460 cells, respectively, compared to the parent compound, Resveratrol (Res). Moreover, the selectivity index (SI) values for BEAS2B cells compared to tumor cells treated with SM-3 were 10.99, 11.81, and 18.49 for A549, H292, and H460 cell lines, respectively. Therefore, SM-3 treatment led to reduced proliferation rates and colony formation in lung cancer cells. In our study, spheroids treated with SM-3 showed a higher proportion of dead spheroids compared to those treated with Res. Additionally, SM-3 treatment resulted in decreased expression of stem cell markers (CD133, CD44, and ALDH1A1) and transcription factors (OCT4, NANOG, and SOX2) in spheroids and organoids from human lung cancer cells by inhibiting the mTOR/pAkt pathway. SM-3 was also found to induce autophagic cell death, as indicated by Monodansylcadaverine staining, acidic vesicle formation, and the conversion of LC3BI to LC3BII. Using MM/GBSA calculations, SM-3 exhibited a stronger binding affinity (-25.09 kcal/mol) compared to Res (-18.85 kcal/mol). SM-3 also displayed greater stability during the entire simulation, maintaining lower RMSD values of 2-3 Å even after 80 ns. In summary, the introduction of methyl and methoxy functional groups on Res to create SM-3 effectively suppressed cancer spheroids and organoids formation in lung cancer cells by targeting the upstream mTOR/pAkt pathway.

A tale as old as time - the importance of accelerated lung aging in chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is progressive in nature and predominantly affects older individuals. Lung function decline is a typical part of the aging process, characterized by gradual loss of lung mechanics, airway remodeling, persistent low-grade inflammation of the airways, compromised epithelial barrier function, and impaired immune responses over time.

AREAS COVERED

The pathology of the senile lung is advanced in patients with COPD, whereby genomic damages contribute to structural defects and cellular dysfunction. Primary, antagonistic, and integrative hallmarks of aging are accelerated in COPD, potentiated by cumulative injury sustained from repeated environmental exposures and the interaction with comorbidities. Identification of epigenetic profiles in COPD indicates how cellular processes contribute to the advancement of biological age. Epigenetic abnormalities unique to COPD subpopulations occur in individuals who are immunodeficient, and often experience early onset and increased severity of COPD.

EXPERT OPINION

Accelerated aging processes indicated by epigenetic and other biomarkers may be a promising avenue for early detection, prevention, and subsequent management of COPD. Understanding risk factors contributing to progressive lung function decline and implementation of mitigation strategies such as cessation of smoking, repurposing existing pharmacotherapeutics and development of novel therapies may slow age-related pathologies in COPD. [Figure: see text].

Deciphering the Power of Resveratrol in Mitophagy: From Molecular Mechanisms to Therapeutic Applications

Resveratrol (RES), a natural polyphenolic compound, has garnered significant attention for its therapeutic potential in various pathological conditions. This review explores how RES modulates mitophagy-the selective autophagic degradation of mitochondria essential for maintaining cellular homeostasis. RES promotes the initiation and execution of mitophagy by enhancing PINK1/Parkin-mediated mitochondrial clearance, reducing reactive oxygen species production, and mitigating apoptosis, thereby preserving mitochondrial integrity. Additionally, RES regulates mitophagy through the activation of key molecular targets such as AMP-activated protein kinase (AMPK), the mechanistic target of rapamycin (mTOR), deacetylases (SIRT1 and SIRT3), and mitochondrial quality control (MQC) pathways, demonstrating substantial therapeutic effects in multiple disease models. We provide a detailed account of the biosynthetic pathways, pharmacokinetics, and metabolic characteristics of RES, focusing on its role in mitophagy modulation and implications for medical applications. Potential adverse effects associated with its clinical use are also discussed. Despite its promising therapeutic properties, the clinical application of RES is limited by issues of bioavailability and pharmacokinetic profiles. Future research should concentrate on enhancing RES bioavailability and developing derivatives that precisely modulate mitophagy, thereby unlocking new avenues for disease therapy.

The interplay between probiotics and host autophagy: mechanisms of action and emerging insights

Autophagy, a lysosome-dependent protein degradation mechanism, is a highly conserved catabolic process seen in all eukaryotes. This cell protection system, which is present in all tissues and functions at a basic level, can be up- or downregulated in response to various stresses. A disruption in the natural route of the autophagy process is frequently followed by an interruption in the inherent operation of the body's cells and organs. Probiotics are live bacteria that protect the host through various mechanisms. One of the processes through which probiotics exert their beneficial effects on various cells and tissues is autophagy. Autophagy can assist in maintaining host homeostasis by stimulating the immune system and affecting numerous physiological and pathological responses. In this review, we particularly focus on autophagy impairments occurring in several human illnesses and investigate how probiotics affect the autophagy process under various circumstances.Abbreviation: AD: Alzheimer disease; AKT: AKT serine/threonine kinase; AMPK: 5'AMP-activated protein kinase; ATG: autophagy related; CCl4: carbon tetrachloride; CFS: cell-free supernatant; CMA: chaperone-mediated autophagy; CRC: colorectal cancer; EPS: L. plantarum H31 exopolysaccharide; HD: Huntington disease; HFD: high-fat diet; HPV: human papillomavirus; IFNG/IFN-γ: interferon gamma; IL6: interleukin 6; LGG: L. rhamnosus GG; LPS: lipopolysaccharide; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; NAFLD: non-alcoholic fatty liver disease; NASH: non-alcoholic steatohepatitis; PD: Parkinson disease; Pg3G: pelargonidin-3-O-glucoside; PI3K: phosphoinositide 3-kinase; PolyQ: polyglutamine; ROS: reactive oxygen species; SCFAs: short-chain fatty acids; SLAB51: a novel formulation of lactic acid bacteria and bifidobacteria; Slp: surface layer protein (of acidophilus NCFM); SNCA: synuclein alpha; ULK1: unc-51 like autophagy-activating kinase 1; YB: B. longum subsp. infantis YB0411; YFP: yeast fermentate prebiotic.

Unraveling the Beneficial Role of Resveratrol in Fructose-Induced Non-Alcoholic Steatohepatitis with a Focus on the AMPK/Nrf2 Signaling Axis

Background and Objectives: High fructose intake is associated with non-alcoholic fatty liver disease (NAFLD), a chronic liver disease that is on the rise worldwide. New alternatives for treatment, such as bioactive phytochemicals, are needed. The aim of this study was to investigate the beneficial role of resveratrol in treating non-alcoholic steatohepatitis (NASH). Materials and Methods: Sixty male albino rats were allocated to three groups: group I, the normal control group; group II, the fructose-enriched diet group (FED), which was fed a 70% fructose diet for six weeks to induce NASH; and group III, the resveratrol-FED group (RES + FED), which was given the same FED diet plus an oral dose of 70 mg/kg resveratrol (RES) every day for an additional six weeks. We performed histological evaluations and assessed blood lipids and liver enzymes to study resveratrol's impact on NASH. Quantitative real-time PCR was used to assess the mRNA expression of nuclear factor E2-related factor 2 (Nrf2) in the liver samples. ELISA was used to measure Beclin 1, AMPK, IL-6, and the DNA-binding activity of Nrf2. Oxidative stress indicators, including GSH, SOD, and MDA, were evaluated spectrophotometrically. Results: Resveratrol effectively alleviated the biochemical and histopathological abnormalities associated with NASH, improving autophagy by raising Beclin 1 levels while reducing inflammation by decreasing IL-6 levels. Furthermore, resveratrol restored the liver architecture and the oxidative balance, as evidenced by the decreased MDA levels and improved antioxidant status via elevated GSH and SOD activities, as well as the activation of the AMPK/Nrf2 signaling axis. Conclusions: This study specifically examines resveratrol's therapeutic effects in a high-fructose diet-induced NASH model, focusing on the AMPK/Nrf2 signaling pathway to address oxidative stress and autophagy, providing novel insights into its molecular mechanism of action. Resveratrol reduces NASH by boosting autophagy and activating the AMPK/Nrf2 pathway. These findings underscore the potential of resveratrol as a promising therapeutic agent that can support treatment alongside conventional medications in the management of non-alcoholic steatohepatitis (NASH).

Relationship Between Dietary Nutrient Intake and Autophagy-Related Genes in Obese Humans: A Narrative Review

Obesity is one of the world's major public health challenges. Its pathogenesis and comorbid metabolic disorders share common mechanisms, such as mitochondrial or endoplasmic reticulum dysfunction or oxidative stress, gut dysbiosis, chronic inflammation and altered autophagy. Numerous pro-autophagy dietary interventions are being investigated for their potential obesity-preventing or therapeutic effects. We summarize current data on the relationship between autophagy and obesity, and discuss various dietary interventions as regulators of autophagy-related genes in the prevention and ultimate treatment of obesity in humans, as available in scientific databases and published through July 2024. Lifestyle modifications (such as calorie restriction, intermittent fasting, physical exercise), including following a diet rich in flavonoids, antioxidants, specific fatty acids, specific amino acids and others, have shown a beneficial role in the induction of this process. The activation of autophagy through various nutritional interventions tends to elicit a consistent response, characterized by the induction of certain kinases (including AMPK, IKK, JNK1, TAK1, ULK1, and VPS34) or the suppression of others (like mTORC1), the deacetylation of proteins, and the alleviation of inhibitory interactions between BECN1 and members of the Bcl-2 family. Significant health/translational properties of many nutrients (nutraceuticals) can affect chronic disease risk through various mechanisms that include the activation or inhibition of autophagy. The role of nutritional intervention in the regulation of autophagy in obesity and its comorbidities is not yet clear, especially in obese individuals.

The Cognitive Restoration Effects of Resveratrol: Insight Molecular through Behavioral Studies in Various Cognitive Impairment Models

Cognition is essential for daily activities and progressively deteriorates with age due to various factors leading to cognitive decline. This decline often begins with memory impairment and advances to broader cognitive dysfunctions. Resveratrol (RES), a natural phenolic compound found in red wine, has garnered significant attention for its potential to prevent cognitive decline. This review aims to synthesize the latest preclinical data on the cognitive restorative effects of RES. We highlight RES activities from cellular mechanisms to behavioral outcomes. Evidence from various cognitive impairment models demonstrates that RES exerts neuroprotective effects through multiple mechanisms, including anti-inflammatory, antioxidative, anti-apoptotic, and neurotrophic actions, all of which contribute to cognitive enhancement in behavioral studies. Despite the established role of RES in mitigating memory decline, our review identifies a critical gap in behavioral studies regarding cognitive flexibility. Further research in this domain is recommended. Additionally, species-specific pharmacokinetic differences may account for the inconsistencies between preclinical and clinical outcomes, particularly in rats and humans. We propose that formulations designed to delay gut metabolism through enterohepatic circulation could enhance the translational potential of RES. Furthermore, long-term studies are needed to determine the optimal dose capable of maximizing health benefits without raising toxicity during chronic use.

Exploration of Nutraceutical Potentials of Isorhapontigenin, Oxyresveratrol and Pterostilbene: A Metabolomic Approach

Resveratrol (trans-3,5,4'-trihydroxystilbene, RES) is one of the most well-known natural products with numerous health benefits. To explore the nutraceutical potentials of some dietary RES derivatives including isorhapontigenin (trans-3,5,4'-trihydroxy-3'-methoxystilbene, ISO), oxyresveratrol (trans-3,5,2',4'-tetrahydroxystilbene, OXY) and pterostilbene (trans-3,5-dimethoxy-4'-hydroxystilbene, PTS), their impacts on metabolism and health were assessed in Sprague Dawley rats after a two-week daily oral administration at the dose of 100 µmol/kg/day. Non-targeted metabolomic analyses were carried out with the liver, heart, brain and plasma samples using gas chromatography-tandem mass spectrometry (GC-MS/MS). Notable in vivo health benefits were observed, as the rats received ISO, PTS or RES showed less body weight gain; the rats received OXY or RES displayed healthier fasting blood glucose levels; while all of the tested stilbenes exhibited cholesterol-lowering effects. Additionally, many important metabolic pathways such as glycolysis, pentose phosphate pathway, tricarboxylic acid cycle and fatty acid oxidation were found to be modulated by the tested stilbenes. Besides the reaffirmation of the well-known beneficial effects of RES in diabetes, obesity, cardiovascular disease and Alzheimer's disease, the metabolomic analyses also suggest the anti-diabetic, cardio-, hepato- and neuro-protective activities of ISO; the anti-diabetic, cardio-, hepato- and neuro-protective effects of OXY; and the anti-aging, anti-inflammatory, cardio-, hepato- and neuro-protective potential of PTS. Interestingly, although these stilbenes share a similar structure, their biological activities appear to be distinct. In conclusion, similarly to RES, ISO, OXY and PTS have emerged as promising candidates for further nutraceutical development.

Natural Autophagy Activators to Fight Age-Related Diseases

The constant increase in the elderly population presents significant challenges in addressing new social, economic, and health problems concerning this population. With respect to health, aging is a primary risk factor for age-related diseases, which are driven by interconnected molecular hallmarks that influence the development of these diseases. One of the main mechanisms that has attracted more attention to aging is autophagy, a catabolic process that removes and recycles damaged or dysfunctional cell components to preserve cell viability. The autophagy process can be induced or deregulated in response to a wide range of internal or external stimuli, such as starvation, oxidative stress, hypoxia, damaged organelles, infectious pathogens, and aging. Natural compounds that promote the stimulation of autophagy regulatory pathways, such as mTOR, FoxO1/3, AMPK, and Sirt1, lead to increased levels of essential proteins such as Beclin-1 and LC3, as well as a decrease in p62. These changes indicate the activation of autophagic flux, which is known to be decreased in cardiovascular diseases, neurodegeneration, and cataracts. The regulated administration of natural compounds offers an adjuvant therapeutic alternative in age-related diseases; however, more experimental evidence is needed to support and confirm these health benefits. Hence, this review aims to highlight the potential benefits of natural compounds in regulating autophagy pathways as an alternative approach to combating age-related diseases.

Repurposing ezetimibe as a neuroprotective agent in a rotenone-induced Parkinson's disease model in rats: Role of AMPK/SIRT-1/PGC-1α signaling and autophagy

As a severe neurological disorder, Parkinson's disease (PD) is distinguished by dopaminergic neuronal degeneration in the substantia nigra (SN), culminating in motor impairments. Several studies have shown that activation of the AMPK/SIRT1/PGC1α pathway contributes to an increase in mitochondrial biogenesis and is a promising candidate for the management of PD. Furthermore, turning on the AMPK/SIRT1/PGC1α pathway causes autophagy activation, which is fundamental for maintaining neuronal homeostasis. Interestingly, ezetimibe is an antihyperlipidemic agent that was recently reported to possess pleiotropic properties in neurology by triggering the phosphorylation and activation of AMPK. Thus, our study aimed to investigate the neuroprotective potential of ezetimibe in rats with rotenone-induced PD by activating AMPK. Adult male Wistar rats received rotenone (1.5 mg/kg, s.c.) every other day for 21 days to induce experimental PD. Rats were treated with ezetimibe (5 mg/kg/day, i.p.) 1 h before rotenone. Ezetimibe ameliorated the motor impairments in open field, rotarod and grip strength tests, restored striatal dopamine and tyrosine hydroxylase in the SN, up-regulated p-AMPK, SIRT1, and PGC1α striatal expression, upsurged the expression of ULK1, beclin1, and LC3II/I, reduced Bax/Bcl2 ratio, and alleviated rotenone-induced histopathological changes in striatum and SN. Our findings also verified the contribution of AMPK activation to the neuroprotective effect of ezetimibe by using the AMPK inhibitor dorsomorphin. Together, this work revealed that ezetimibe exerts a neuroprotective impact in rotenone-induced PD by activating AMPK/SIRT-1/PGC-1α signaling, enhancing autophagy, and attenuating apoptosis. Thus, ezetimibe's activation of AMPK could hold significant therapeutic promise for PD management.

Apigenin Attenuates Transverse Aortic Constriction-Induced Myocardial Hypertrophy: The Key Role of miR-185-5p/SREBP2-Mediated Autophagy

Introduction

Apigenin is a natural flavonoid compound with promising potential for the attenuation of myocardial hypertrophy (MH). The compound can also modulate the expression of miR-185-5p that both promote MH and suppress autophagy. The current attempts to explain the anti-MH effect of apigenin by focusing on changes in miR-185-5p-mediated autophagy.

Methods

Hypertrophic symptoms were induced in rats using transverse aortic constriction (TAC) method and in cardiomyocytes using Ang II and then handled with apigenin. Changes in myocardial function and structure and cell viability and surface area were measured. The role of miR-185-5p in the anti-MH function of apigenin was explored by detecting changes in autophagic processes and miR-185-5p/SREBP2 axis.

Results

TAC surgery induced weight increase, structure destruction, and collagen deposition in hearts of model rats. Ang II suppresses cardiomyocyte viability and increased cell surface area. All these impairments were attenuated by apigenin and were associated with the restored level of autophagy. At the molecular level, the expression of miR-185-5p was up-regulated by TAC, while the expression of SREBP2 was down-regulated, which was reserved by apigenin both in vivo and in vitro. The induction of miR-185-5p in cardiomyocytes could counteracted the protective effects of apigenin.

Discussion

Collectively, the findings outlined in the current study highlighted that apigenin showed anti-MH effects. The effects were related to the inhibition of miR-185-5p and activation of SREBP, which contributed to the increased autophagy.

Immunomodulatory and chemopreventive effects of resveratrol on the digestive system cancers

Resveratrol (RSV), the primary polyphenol found in grapes, has been revealed to have anti-inflammatory properties by reducing the capacity of the peripheral blood mononuclear cells to produce pro-inflammatory cytokines, including IL-1β, IL-6, IL-1ra and TNFα. Considering the close association between chronic inflammation and cancer development, RSV's immunomodulatory properties are one way by which the polyphenol may inhibit cancer initiation, proliferation, neovascularization, and migration. Resveratrol influences the generation of microtumor environment which is one of the key factors in cancer progress. In addition to immunomodulation, RSV inhibits cancer development by expressing anti-oxidant effects, causing cell cycle arrest, stimulating the function of certain enzymes, and activating cell signaling pathways. The end outcome is one of the various forms of cell death, including apoptosis, pyroptosis, necroptosis, and more, as it has been observed in vitro. RSV has been shown to act against cancer in practically every organ, while its effects on colon cancer have been documented more frequently. It is remarkable that longer-term clinical studies that may have established the potential for this natural substance to serve as a therapeutic adjuvant to traditional anti-cancer medications were not prompted by the encouraging outcomes seen with cancer cells treated with non-toxic doses of resveratrol. The current review aims to assess the recent findings about the immunological and anti-cancer characteristics of RSV, with a particular emphasis on cancers of the digestive tract, as a challenge for future clinical research that may contribute to the better prognosis of cancer.

Cytotoxic stress caused by azalamellarin D (AzaD) interferes with cellular protein translation by targeting the nutrient-sensing kinase mTOR

Analogs of pyrrole alkaloid lamellarins exhibit anticancer activity by modulating multiple cellular events. Lethal doses of several lamellarins were found to enhance autophagy flux in HeLa cells, suggesting that lamellarins may modulate protein homeostasis through the interference of proteins or kinases controlling energy and nutrient metabolism. To further delineate molecular mechanisms and their targets, our results herein show that azalamellarin D (AzaD) cytotoxicity could cause translational attenuation, as indicated by a change in eIF2α phosphorylation. Intriguingly, acute AzaD treatment promoted the phosphorylation of GCN2, a kinase that transduces the integrated stress response (ISR), and prolonged exposure to AzaD could increase the levels of the phosphorylated forms of eIF2α and the other ISR kinase protein kinase R (PKR). However, the effects of AzaD on ISR signalling were marginally abrogated in cells with genetic deletion of GCN2 and PKR, and evaluation of protein target engagement by cellular thermal shift assay (CETSA) revealed no significant interaction between AzaD and ISR kinases. Further investigation revealed that acute AzaD treatment negatively affected mechanistic target of rapamycin (mTOR) phosphorylation and signalling. The analyses by CETSA and computational modelling indicated that mTOR may be a possible protein target for AzaD. These findings indicate the potential for developing lamellarins as novel agents for cancer treatment.

Human Aging and Age-Related Diseases: From Underlying Mechanisms to Pro-Longevity Interventions

As human life expectancy continues to rise, becoming a pressing global concern, it brings into focus the underlying mechanisms of aging. The increasing lifespan has led to a growing elderly population grappling with age-related diseases (ARDs), which strains healthcare systems and economies worldwide. While human senescence was once regarded as an immutable and inexorable phenomenon, impervious to interventions, the emerging field of geroscience now offers innovative approaches to aging, holding the promise of extending the period of healthspan in humans. Understanding the intricate links between aging and pathologies is essential in addressing the challenges presented by aging populations. A substantial body of evidence indicates shared mechanisms and pathways contributing to the development and progression of various ARDs. Consequently, novel interventions targeting the intrinsic mechanisms of aging have the potential to delay the onset of diverse pathological conditions, thereby extending healthspan. In this narrative review, we discuss the most promising methods and interventions aimed at modulating aging, which harbor the potential to mitigate ARDs in the future. We also outline the complexity of senescence and review recent empirical evidence to identify rational strategies for promoting healthy aging.

Autophagy in Its (Proper) Context: Molecular Basis, Biological Relevance, Pharmacological Modulation, and Lifestyle Medicine

Autophagy plays a critical role in maintaining cellular homeostasis and responding to various stress conditions by the degradation of intracellular components. In this narrative review, we provide a comprehensive overview of autophagy's cellular and molecular basis, biological significance, pharmacological modulation, and its relevance in lifestyle medicine. We delve into the intricate molecular mechanisms that govern autophagy, including macroautophagy, microautophagy and chaperone-mediated autophagy. Moreover, we highlight the biological significance of autophagy in aging, immunity, metabolism, apoptosis, tissue differentiation and systemic diseases, such as neurodegenerative or cardiovascular diseases and cancer. We also discuss the latest advancements in pharmacological modulation of autophagy and their potential implications in clinical settings. Finally, we explore the intimate connection between lifestyle factors and autophagy, emphasizing how nutrition, exercise, sleep patterns and environmental factors can significantly impact the autophagic process. The integration of lifestyle medicine into autophagy research opens new avenues for promoting health and longevity through personalized interventions.

Autophagy Deregulation in HIV-1-Infected Cells Increases Extracellular Vesicle Release and Contributes to TLR3 Activation

Human immunodeficiency virus type 1 (HIV-1) infection can result in HIV-associated neurocognitive disorder (HAND), a spectrum of disorders characterized by neurological impairment and chronic inflammation. Combined antiretroviral therapy (cART) has elicited a marked reduction in the number of individuals diagnosed with HAND. However, there is continual, low-level viral transcription due to the lack of a transcription inhibitor in cART regimens, which results in the accumulation of viral products within infected cells. To alleviate stress, infected cells can release accumulated products, such as TAR RNA, in extracellular vesicles (EVs), which can contribute to pathogenesis in neighboring cells. Here, we demonstrate that cART can contribute to autophagy deregulation in infected cells and increased EV release. The impact of EVs released from HIV-1 infected myeloid cells was found to contribute to CNS pathogenesis, potentially through EV-mediated TLR3 (Toll-like receptor 3) activation, suggesting the need for therapeutics to target this mechanism. Three HIV-1 TAR-binding compounds, 103FA, 111FA, and Ral HCl, were identified that recognize TAR RNA and reduce TLR activation. These data indicate that packaging of viral products into EVs, potentially exacerbated by antiretroviral therapeutics, may induce chronic inflammation of the CNS observed in cART-treated patients, and novel therapeutic strategies may be exploited to mitigate morbidity.

Fraxetin pretreatment alleviates cisplatin-induced kidney injury by antagonizing autophagy and apoptosis via mTORC1 activation

Cisplatin-induced kidney injury (CKI) is a common complication of chemotherapy. Fraxetin, derived from Fraxinus bungeana A. DC. bark, has antioxidant, anti-inflammatory, and anti-fibrotic effects. This study aims to investigate fraxetin's effects on CKI and its underlying mechanism in vivo and in vitro. Tubular epithelial cells (TECs) and mice were exposed to cisplatin with and without fraxetin preconditioning assess fraxetin's role in CKI. TECs autophagy was observed using transmission electron microscopy. Apoptosis levels in animal tissues were measured using TUNEL staining. The protective mechanism of fraxetin was explored through pharmacological and genetic regulation of mTORC1. Molecular docking was used to identify potential binding sites between fraxetin and mTORC1. The results indicated that fraxetin pretreatment reduced cisplatin-induced kidney injury in a time- and concentration-dependent way. Fraxetin also decreased autophagy in TECs, as observed through electron microscopy. Tissue staining confirmed that fraxetin pretreatment significantly reduced cisplatin-induced apoptosis. Inhibition of mTORC1 using rapamycin or siRNA reversed the protective effects of fraxetin on apoptosis and autophagy in cisplatin-treated TECs, while activation of mTORC1 enhanced fraxetin's protective effect. Molecular docking analysis revealed that fraxetin can bind to HEAT-repeats binding site on mTORC1 protein. In  summary, fraxetin pretreatment alleviates CKI by antagonizing autophagy and apoptosis via mTORC1 activation. This provides evidence for the potential therapeutic application of fraxetin in CKI.

Natural 2',4-Dihydroxy-4',6'-dimethoxy Chalcone Isolated from Chromolaena tacotana Inhibits Breast Cancer Cell Growth through Autophagy and Mitochondrial Apoptosis

Breast cancer (BC) is one of the most common cancers among women. Effective treatment requires precise tailoring to the genetic makeup of the cancer for improved efficacy. Numerous research studies have concentrated on natural compounds and their anti-breast cancer properties to improve the existing treatment options. Chromolaena tacotana (Klatt) R.M. King and H. Rob (Ch. tacotana) is a notable source of bioactive hydroxy-methylated flavonoids. However, the specific anti-BC mechanisms of these flavonoids, particularly those present in the plant's inflorescences, remain partly undefined. This study focuses on assessing a chalcone derivative extracted from Ch. tacotana inflorescences for its potential to concurrently activate regulated autophagy and intrinsic apoptosis in luminal A and triple-negative BC cells. We determined the chemical composition of the chalcone using ultraviolet (UV) and nuclear magnetic resonance (NMR) spectroscopy. Its selective cytotoxicity against BC cell lines was assessed using the MTT assay. Flow cytometry and Western blot analysis were employed to examine the modulation of proteins governing autophagy and the intrinsic apoptosis pathway. Additionally, in silico simulations were conducted to predict interactions between chalcone and various anti-apoptotic proteins, including the mTOR protein. Chalcone was identified as 2',4-dihydroxy-4',6'-dimethoxy-chalcone (DDC). This compound demonstrated a selective inhibition of BC cell proliferation and triggered autophagy and intrinsic apoptosis. It induced cell cycle arrest in the G0/G1 phase and altered mitochondrial outer membrane potential (∆ψm). The study detected the activation of autophagic LC3-II and mitochondrial pro-apoptotic proteins in both BC cell lines. The regulation of Bcl-XL and Bcl-2 proteins varied according to the BC subtype, yet they showed promising molecular interactions with DDC. Among the examined pro-survival proteins, mTOR and Mcl-1 exhibited the most favorable binding energies and were downregulated in BC cell lines. Further research is needed to fully understand the molecular dynamics involved in the activation and interaction of autophagy and apoptosis pathways in cancer cells in response to potential anticancer agents, like the hydroxy-methylated flavonoids from Ch. tacotana.

Efficacy and Mechanisms of Natural Products as Therapeutic Interventions for Chronic Respiratory Diseases

Chronic respiratory diseases are long-term conditions affecting the airways and other lung components that are characterized by a high prevalence, disability rate, and mortality rate. Further optimization of their treatment is required. Natural products, primarily extracted from organisms, possess specific molecular and structural formulas as well as distinct chemical and physical properties. These characteristics grant them the advantages of safety, gentleness, accessibility, and minimal side effects. The numerous advances in the use of natural products for treating chronic respiratory diseases have provided a steady source of motivation for new drug research and development. In this paper, we introduced the pathogenesis of chronic respiratory diseases and natural products. Furthermore, we classified natural products according to their mechanism for treating chronic respiratory diseases and describe the ways in which these products can alleviate the pathological symptoms. Simultaneously, we elaborate on the signal transduction pathways and biological impacts of natural products' targeting. Additionally, we present future prospects for natural products, considering their combination treatment approaches and administration methods. The significance of this review extends to both the research on preventing and treating chronic respiratory diseases, as well as the advancement of novel drug development in this field.

The Dual Role of Sulforaphane-Induced Cellular Stress-A Systems Biological Study

The endoplasmic reticulum (ER) plays a crucial role in cellular homeostasis. When ER stress is generated, an autophagic self-digestive process is activated to promote cell survival; however, cell death is induced in the case of excessive levels of ER stress. The aim of the present study was to investigate the effect of a natural compound called sulforaphane (SFN) upon ER stress. Our goal was to investigate how SFN-dependent autophagy activation affects different stages of ER stress induction. We approached our scientific analysis from a systems biological perspective using both theoretical and molecular biological techniques. We found that SFN induced the various cell-death mechanisms in a concentration- and time-dependent manner. The short SFN treatment at low concentrations promoted autophagy, whereas the longer treatment at higher concentrations activated cell death. We proved that SFN activated autophagy in a mTORC1-dependent manner and that the presence of ULK1 was required for its function. A low concentration of SFN pre- or co-treatment combined with short and long ER stress was able to promote cell survival via autophagy induction in each treatment, suggesting the potential medical importance of SFN in ER stress-related diseases.

Resveratrol-βcd inhibited premature ovarian insufficiency progression by regulating granulosa cell autophagy

BACKGROUND

The ovarian environment of premature ovarian insufficiency (POI) patients exhibits immune dysregulation, which leads to excessive secretion of numerous proinflammatory cytokines that affect ovarian function. An abnormal level of macrophage polarization directly or indirectly inhibits the differentiation of ovarian granulosa cells and steroid hormone production, ultimately leading to POI. Resveratrol, as a health supplement, has been widely recognized for its safety. There is a substantial amount of evidence indicating that resveratrol and its analogs possess significant immune-regulatory functions. It has also been reported that resveratrol can effectively inhibit the progression of POI. However, the underlying immunological and molecular mechanisms through which resveratrol inhibits the progression of POI are still unclear.

RESULTS

Our preliminary reports have shown that resveratrol-βcd, the beta-cyclodextrin complex of resveratrol, significantly enhances the stability of resveratrol. Resveratrol-βcd could regulate the dysfunctional immune status of macrophages and T cells in the tumor microenvironment. In this study, we treated busulfan and cyclophosphamide (B/C)-treated mice, which were used as a POI model, with resveratrol-βcd. After resveratrol-βcd treatment, the levels of IL-6 in the ovaries were significantly increased, and the progression of POI was suppressed. IL-6 activated granulosa cells (GCs) through soluble IL-6R (sIL-6R), promoting autophagy in GCs. Resveratrol-βcd and IL-6 had a synergistic effect on enhancing autophagy in GCs and promoting E2 secretion.

CONCLUSIONS

We partially elucidated the immune mechanism by which resveratrol inhibits the progression of POI and the autophagy-regulating function of GCs. This provides a theoretical basis for using resveratrol to prevent POI in future studies and clinical guidance.

Combined Deep Learning and Molecular Modeling Techniques on the Virtual Screening of New mTOR Inhibitors from the Thai Mushroom Database

The mammalian target of rapamycin (mTOR) is a protein kinase of the PI3K/Akt signaling pathway that regulates cell growth and division and is an attractive target for cancer therapy. Many reports on finding alternative mTOR inhibitors available in a database contain a mixture of active compound data with different mechanisms, which results in an increased complexity for training the machine learning models based on the chemical features of active compounds. In this study, a deep learning model supported by principal component analysis (PCA) and structural methods was used to search for an alternative mTOR inhibitor from mushrooms. The mTORC1 active compound data set from the PubChem database was first filtered for only the compounds resided near the first-generation inhibitors (rapalogs) within the first two PCA coordinates of chemical features. A deep learning model trained by the filtered data set captured the main characteristics of rapalogs and displayed the importance of steroid cores. After that, another layer of virtual screening by molecular docking calculations was performed on ternary complexes of FKBP12-FRB domains and six compound candidates with high "active" probability scores predicted by the deep learning models. Finally, all-atom molecular dynamics simulations and MMPBSA binding energy analysis were performed on two selected candidates in comparison to rapamycin, which confirmed the importance of ring groups and steroid cores for interaction networks. Trihydroxysterol from Lentinus polychrous Lev. was predicted as an interesting candidate due to the small but effective interaction network that facilitated FKBP12-FRB interactions and further stabilized the ternary complex.

A Novel Tri-Hydroxy-Methylated Chalcone Isolated from Chromolaena tacotana with Anti-Cancer Potential Targeting Pro-Survival Proteins

Chromolaena tacotana (Klatt) R. M. King and H. Rob (Ch. tacotana) contains bioactive flavonoids that may have antioxidant and/or anti-cancer properties. This study investigated the potential anti-cancer properties of a newly identified chalcone isolated from the inflorescences of the plant Chromolaena tacotana (Klatt) R. M. King and H. Rob (Ch. tacotana). The chalcone structure was determined using HPLC/MS (QTOF), UV, and NMR spectroscopy. The compound cytotoxicity and selectivity were evaluated on prostate, cervical, and breast cancer cell lines using the MTT assay. Apoptosis and autophagy induction were assessed through flow cytometry by detecting annexin V/7-AAD, active Casp3/7, and LC3B proteins. These results were supported by Western blot analysis. Mitochondrial effects on membrane potential, as well as levels of pro- and anti-apoptotic proteins were analyzed using flow cytometry, fluorescent microscopy, and Western blot analysis specifically on a triple-negative breast cancer (TNBC) cell line. Furthermore, molecular docking (MD) and molecular dynamics (MD) simulations were performed to evaluate the interaction between the compounds and pro-survival proteins. The compound identified as 2',3,4-trihydroxy-4',6'-dimethoxy chalcone inhibited the cancer cell line proliferation and induced apoptosis and autophagy. MDA-MB-231, a TNBC cell line, exhibited the highest sensitivity to the compound with good selectivity. This activity was associated with the regulation of mitochondrial membrane potential, activation of the pro-apoptotic proteins, and reduction of anti-apoptotic proteins, thereby triggering the intrinsic apoptotic pathway. The chalcone consistently interacted with anti-apoptotic proteins, particularly the Bcl-2 protein, throughout the simulation period. However, there was a noticeable conformational shift observed with the negative autophagy regulator mTOR protein. Future studies should focus on the molecular mechanisms underlying the anti-cancer potential of the new chalcone and other flavonoids from Ch. tacotana, particularly against predominant cancer cell types.

Natural Compounds Targeting the Autophagy Pathway in the Treatment of Colorectal Cancer

Autophagy is a highly conserved intracellular degradation pathway by which misfolded proteins or damaged organelles are delivered in a double-membrane vacuolar vesicle and finally degraded by lysosomes. The risk of colorectal cancer (CRC) is high, and there is growing evidence that autophagy plays a critical role in regulating the initiation and metastasis of CRC; however, whether autophagy promotes or suppresses tumor progression is still controversial. Many natural compounds have been reported to exert anticancer effects or enhance current clinical therapies by modulating autophagy. Here, we discuss recent advancements in the molecular mechanisms of autophagy in regulating CRC. We also highlight the research on natural compounds that are particularly promising autophagy modulators for CRC treatment with clinical evidence. Overall, this review illustrates the importance of autophagy in CRC and provides perspectives for these natural autophagy regulators as new therapeutic candidates for CRC drug development.

Autophagy Reduces the Degradation and Promotes Membrane Localization of Occludin to Enhance the Intestinal Epithelial Tight Junction Barrier against Paracellular Macromolecule Flux

BACKGROUND AND AIMS

Functional loss of the gut epithelium's paracellular tight junction [TJ] barrier and defective autophagy are factors potentiating inflammatory bowel disease [IBD]. Previously, we showed the role of autophagy in enhancing the intestinal TJ barrier via pore-forming claudin-2 degradation. How autophagy regulates the TJ barrier-forming proteins remains unknown. Here, we investigated the role of autophagy in the regulation of occludin, a principal TJ component involved in TJ barrier enhancement.

RESULTS

Autophagy induction using pharmacological activators and nutrient starvation increased total occludin levels in intestinal epithelial cells, mouse colonocytes and human colonoids. Autophagy induction enriched membrane occludin levels and reduced paracellular permeability of macromolecules. Autophagy-mediated TJ barrier enhancement was contingent on the presence of occludin as OCLN-/- nullified its TJ barrier-enhancing effect against macromolecular flux. Autophagy inhibited the constitutive degradation of occludin by preventing its caveolar endocytosis from the membrane and protected against inflammation-induced TJ barrier loss. Autophagy enhanced the phosphorylation of ERK-1/2 and inhibition of these kinases in Caco-2 cells and human colonic mucosa prevented the macromolecular barrier-enhancing effects of autophagy. In vivo, autophagy induction by rapamycin enhanced occludin levels in wild-type mouse intestines and protected against lipopolysaccharide- and tumour necrosis factor-α-induced TJ barrier loss. Disruption of autophagy with acute Atg7 knockout in adult mice decreased intestinal occludin levels, increasing baseline colonic TJ permeability and exacerbating the effect of experimental colitis.

CONCLUSION

Our data suggest a novel role of autophagy in promoting the intestinal TJ barrier by increasing occludin levels in an ERK1/2 mitogen-activated protein kinase-dependent mechanism.

Role of Tau in Various Tauopathies, Treatment Approaches, and Emerging Role of Nanotechnology in Neurodegenerative Disorders

A few protein kinases and phosphatases regulate tau protein phosphorylation and an imbalance in their enzyme activity results in tau hyper-phosphorylation. Aberrant tau phosphorylation causes tau to dissociate from the microtubules and clump together in the cytosol to form neurofibrillary tangles (NFTs), which lead to the progression of neurodegenerative disorders including Alzheimer's disease (AD) and other tauopathies. Hence, targeting hyperphosphorylated tau protein is a restorative approach for treating neurodegenerative tauopathies. The cyclin-dependent kinase (Cdk5) and the glycogen synthase kinase (GSK3β) have both been implicated in aberrant tau hyperphosphorylation. The limited transport of drugs through the blood-brain barrier (BBB) for reaching the central nervous system (CNS) thus represents a significant problem in the development of drugs. Drug delivery systems based on nanocarriers help solve this problem. In this review, we discuss the tau protein, regulation of tau phosphorylation and abnormal hyperphosphorylation, drugs in use or under clinical trials, and treatment strategies for tauopathies based on the critical role of tau hyperphosphorylation in the pathogenesis of the disease. Pathology of neurodegenerative disease due to hyperphosphorylation and various therapeutic approaches including nanotechnology for its treatment.

Trans-gnetin H isolated from the seeds of Paeonia species induces autophagy via inhibiting mTORC1 signalling through AMPK activation

Paeonia is a well-known species of ornamental plants, traditional Chinese medicines, and emerging oilseed crops. Apart from nutritional unsaturated fatty acids, the seeds of peonies are rich in stilbenes characterized by their wide-ranging health-promoting properties. Although the typical stilbene resveratrol has been widely reported for its multiple bioactivities, it remains uncertain whether the trimer of resveratrol trans-gnetin H has properties that regulate cancer cell viability, let alone the underlying mechanism. Autophagy regulated by trans-gnetin H was detected by western blotting, immunofluorescence, and quantitative real-time PCR. The effects of trans-gnetin H on apoptosis and proliferation were examined by flow cytometry, colony formation and Cell Counting Kit-8 assays. Trans-gnetin H significantly inhibits cancer cell viability through autophagy by suppressing the phosphorylation of TFEB and promoting its nuclear transport. Mechanistically, trans-gnetin H inhibits the activation and lysosome translocation of mTORC1 by inhibiting the activation of AMPK, indicating that AMPK is a checkpoint for mTORC1 inactivation induced by trans-gnetin H. Moreover, the binding of TSC2 to Rheb was markedly increased in response to trans-gnetin H stimulation. Similarly, trans-gnetin H inhibited the interaction between Raptor and RagC in an AMPK-dependent manner. More importantly, trans-gnetin H-mediated autophagy highly depends on the AMPK-mTORC1 axis. We propose a regulatory mechanism by which trans-gnetin H inhibits the activation of the mTORC1 pathway to control cell autophagy.

mTOR Signaling Disruption and Its Association with the Development of Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder characterized by impairments in social interaction and communication along with repetitive stereotypic behaviors. Currently, there are no specific biomarkers for diagnostic screening or treatments available for autistic patients. Numerous genetic disorders are associated with high prevalence of ASD, including tuberous sclerosis complex, phosphatase and tensin homolog, and fragile X syndrome. Preclinical investigations in animal models of these diseases have revealed irregularities in the PI3K/Akt/mTOR signaling pathway as well as ASD-related behavioral defects. Reversal of the downstream molecular irregularities, associated with mTOR hyperactivation, improved the behavioral deficits observed in the preclinical investigations. Plant bioactive molecules have shown beneficial pre-clinical evidence in ASD treatment by modulating the PI3K/Akt/mTOR pathway. In this review, we summarize the involvement of the PI3K/Akt/mTOR pathway as well as the genetic alterations of the pathway components and its critical impact on the development of the autism spectrum disorder. Mutations in negative regulators of mTORC1, such as TSC1, TSC2, and PTEN, result in ASD-like phenotypes through the disruption of the mTORC1-mediated signaling. We further discuss the various naturally occurring phytoconstituents that have been identified to be bioactive and modulate the pathway to prevent its disruption and contribute to beneficial therapeutic effects in ASD.

Oxidative Stress Contributes to Inflammatory and Cellular Damage in Systemic Lupus Erythematosus: Cellular Markers and Molecular Mechanism

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease with complex pathogenesis, the treatment of which relies exclusively on the use of immunosuppressants. Increased oxidative stress is involved in causing inflammatory and cellular defects in the pathogenesis of SLE. Various inflammatory and cellular markers including oxidative modifications of proteins, lipids, and DNA contribute to immune system dysregulation and trigger an aggressive autoimmune attack through molecular mechanisms like enhanced NETosis, mTOR pathway activation, and imbalanced T-cell differentiation. Accordingly, the detection of inflammatory and cellular markers is important for providing an accurate assessment of the extent of oxidative stress. Oxidative stress also reduces DNA methylation, thus allowing the increased expression of affected genes. As a result, pharmacological approaches targeting oxidative stress yield promising results in treating patients with SLE. The purpose of this review is to examine the involvement of oxidative stress in the pathogenesis and management of SLE.

Does treatment with autophagy-enhancers and/or ROS-scavengers alleviate behavioral and neurochemical consequences of low-dose rotenone-induced mild mitochondrial dysfunction in mice?

Bipolar-disorder's pathophysiology and the mechanism by which medications exert their beneficial effect is yet unknown, but others' and our data implicate patients' brain mitochondrial-dysfunction and its amendment by mood-stabilizers. We recently designed a novel mouse bipolar-disorder-like model using chronic administration of a low-dose of the oxidative-phosphorylation complex I inhibitor, rotenone. Four and eight weeks rotenone treatment induced manic- and depressive-like behavior, respectively, accompanied by mood-related neurochemical changes. Here we aimed to investigate whether each of the autophagy-enhancers lithium (a mood-stabilizer), trehalose and resveratrol and/or each of the reactive oxygen species (ROS)-scavengers, resveratrol and N-acetylcystein and/or the combinations lithium+resveratrol or trehalose+N-acetylcystein, can ameliorate behavioral and neurochemical consequences of neuronal mild mitochondrial-dysfunction. We observed that lithium, trehalose and N-acetylcystein reversed rotenone-induced manic-like behavior as well as deviations in protein levels of mitochondrial complexes and the autophagy marker LC3-II. This raises the possibility that mild mitochondrial-dysfunction accompanied by impaired autophagy and a very mild increase in ROS levels are related to predisposition to manic-like behavior. On the other hand, although, as expected, most of the drugs tested eliminated the eight weeks rotenone-induced increase in protein levels of all hippocampal mitochondrial complexes, only lithium ubiquitously ameliorated the depressive-like behaviors. We cautiously deduce that aberrant autophagy and/or elevated ROS levels are not involved in predisposition to the depressive phase of bipolar-like behavior. Rather, that amending the depressive-like characteristics requires different mitochondria-related interventions. The latter might be antagonizing N-methyl-D-aspartate receptors (NMDARs), thus protecting from disruption of mitochondrial calcium homeostasis and its detrimental consequences. In conclusion, our findings suggest that by-and-large, among the autophagy-enhancers and ROS-scavengers tested, lithium is the most effective in counteracting rotenone-induced changes. Trehalose and N-acetylcystein may also be effective in attenuating manic-like behavior.

Insulin resistance in Alzheimer's disease: The genetics and metabolomics links

Alzheimer's disease (AD) is a neurodegenerative disease with significant socioeconomic burden worldwide. Although genetics and environmental factors play a role, AD is highly associated with insulin resistance (IR) disorders such as metabolic syndrome (MS), obesity, and type two diabetes mellitus (T2DM). These findings highlight a shared pathogenesis. The use of metabolomics as a downstream systems' biology (omics) approach can help to identify these shared metabolic traits and assist in the early identification of at-risk groups and potentially guide therapy. Targeting the shared AD-IR metabolic trait with lifestyle interventions and pharmacological treatments may offer promising AD therapeutic approach. In this narrative review, we reviewed the literature on the AD-IR pathogenic link, the shared genetics and metabolomics biomarkers between AD and IR disorders, as well as the lifestyle interventions and pharmacological treatments which target this pathogenic link.

Neuroprotective Effects of Agri-Food By-Products Rich in Phenolic Compounds

Neurodegenerative diseases are known for their wide range of harmful conditions related to progressive cell damage, nervous system connections and neuronal death. These pathologies promote the loss of essential motor and cognitive functions, such as mobility, learning and sensation. Neurodegeneration affects millions of people worldwide, and no integral cure has been created yet. Here, bioactive compounds have been proven to exert numerous beneficial effects due to their remarkable bioactivity, so they could be considered as great options for the development of new neuroprotective strategies. Phenolic bioactives have been reported to be found in edible part of plants; however, over the last years, a large amount of research has focused on the phenolic richness that plant by-products possess, which sometimes even exceeds the content in the pulp. Thus, their possible application as an emergent neuroprotective technique could also be considered as an optimal strategy to revalorize these agricultural residues (those originated from plant processing). This review aims to summarize main triggers of neurodegeneration, revise the state of the art in plant extracts and their role in avoiding neurodegeneration and discuss how their main phenolic compounds could exert their neuroprotective effects. For this purpose, a diverse search of studies has been conducted, gathering a large number of papers where by-products were used as strong sources of phenolic compounds for their neuroprotective properties. Finally, although a lack of investigation is quite remarkable and greatly limits the use of these compounds, phenolics remain attractive for research into new multifactorial anti-neurodegenerative nutraceuticals.

Mitochondrial dysfunctions, oxidative stress and neuroinflammation as therapeutic targets for neurodegenerative diseases: An update on current advances and impediments

Neurodegenerative diseases (NDs) such as Alzheimer disease (AD), Parkinson disease (PD), and Huntington disease (HD) represent a major socio-economic challenge in view of their high prevalence yet poor treatment outcomes affecting quality of life. The major challenge in drug development for these NDs is insufficient clarity about the mechanisms involved in pathogenesis and pathophysiology. Mitochondrial dysfunction, oxidative stress and inflammation are common pathways that are linked to neuronal abnormalities and initiation of these diseases. Thus, elucidating the shared initial molecular and cellular mechanisms is crucial for recognizing novel remedial targets, and developing therapeutics to impede or stop disease progression. In this context, use of multifunctional compounds at early stages of disease development unclogs new avenues as it acts on act on multiple targets in comparison to single target concept. In this review, we summarize overview of the major findings and advancements in recent years focusing on shared mechanisms for better understanding might become beneficial in searching more potent pharmacological interventions thereby reducing the onset or severity of various NDs.

Resveratrol Ameliorates Hyperglycemic Cultured Cells and Inhibits the Rheb/mTOR Interaction

Resveratrol (RSV) is a natural polyphenol with anti-diabetic effects and has been reported to ameliorate diabetes-induced metabolic disorders through regulating activities of the mTOR signaling pathway. To delineate the effects of RSV treatment on the mTOR signaling pathway, hyperglycemic HepG2 cells were used for the following experiments. Cellular glucose uptake assays showed that high-glucose levels in the culture medium decelerate the glucose uptake of cultured cells. Co-immunoprecipitation showed that high-glucose culture promotes the interaction between mTOR and Rheb-GTP, which is the active form of Rheb. RSV treatment of the cells suppressed this interaction and accelerated the glucose uptake. Western blotting revealed that RSV down-regulated members of the mTOR signaling pathway, namely SREBP1, p70, and S6. Additionally, RSV ameliorated the metabolic disorders, including the decreased levels of AMPK, glycogen synthase, and glucose-6-phosphatase, in hyperglycemic HepG2 cells. These results indicate that RSV inhibits the Rheb/mTOR interaction and ameliorates metabolic disorders associated with high-glucose levels.

Suffruticosol C-Mediated Autophagy and Cell Cycle Arrest via Inhibition of mTORC1 Signaling

Paeonia species are well-known ornamental plants that are used in traditional Chinese medicines. The seeds of these species are rich in stilbenes, which have wide-ranging health-promoting effects. In particular, resveratrol, which is a common stilbene, is widely known for its anticancer properties. Suffruticosol C, which is a trimer of resveratrol, is the most dominant stilbene found in peony seeds. However, it is not clear whether suffruticosol C has cancer regulating properties. Therefore, in the present study, we aimed to determine the effect of suffruticosol C against various cancer cell lines. Our findings showed that suffruticosol C induces autophagy and cell cycle arrest instead of cell apoptosis and ferroptosis. Mechanistically, suffruticosol C regulates autophagy and cell cycle via inhibiting the mechanistic target of rapamycin complex 1 (mTORC1) signaling. Thus, our findings imply that suffruticosol C regulates cancer cell viability by inducing autophagy and cell cycle arrest via the inhibition of mTORC1 signaling.

Genome Tectonics: Linking Dynamic Genome Organization with Cellular Nutrients

BACKGROUND

Our daily intake of food provides nutrients for the maintenance of health, growth, and development. The field of nutrigenomics aims to link dietary intake/nutrients to changes in epigenetic status and gene expression.

SUMMARY

Although the relationship between our diet and our genes in under intense investigation, there is still a significant aspect of our genome that has received little attention with regard to this. In the past 15 years, the importance of genome organization has become increasingly evident, with research identifying small-scale local changes to large segments of the genome dynamically repositioning within the nucleus in response to/or mediating change in gene expression. The discovery of these dynamic processes and organization maybe as significant as dynamic plate tectonics is to geology, there is little information tying genome organization to specific nutrients or dietary intake.

KEY MESSAGES

Here, we detail key principles of genome organization and structure, with emphasis on genome folding and organization, and link how these contribute to our future understand of nutrigenomics.

Novel insights into exhaustive exercise-induced myocardial injury: Focusing on mitochondrial quality control

Regular moderate-intensity exercise elicits benefit cardiovascular health outcomes. However, exhaustive exercise (EE) triggers arrhythmia, heart failure, and sudden cardiac death. Therefore, a better understanding of unfavorable heart sequelae of EE is important. Various mechanisms have been postulated for EE-induced cardiac injury, among which mitochondrial dysfunction is considered the cardinal machinery for pathogenesis of various diseases. Mitochondrial quality control (MQC) is critical for clearance of long-lived or damaged mitochondria, regulation of energy metabolism and cell apoptosis, maintenance of cardiac homeostasis and alleviation of EE-induced injury. In this review, we will focus on MQC mechanisms and propose mitochondrial pathophysiological targets for the management of EE-induced myocardial injury. A thorough understanding of how MQC system functions in the maintenance of mitochondrial homeostasis will provide a feasible rationale for developing potential therapeutic interventions for EE-induced injury.

Therapeutic Antiaging Strategies

Aging constitutes progressive physiological changes in an organism. These changes alter the normal biological functions, such as the ability to manage metabolic stress, and eventually lead to cellular senescence. The process itself is characterized by nine hallmarks: genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. These hallmarks are risk factors for pathologies, such as cardiovascular diseases, neurodegenerative diseases, and cancer. Emerging evidence has been focused on examining the genetic pathways and biological processes in organisms surrounding these nine hallmarks. From here, the therapeutic approaches can be addressed in hopes of slowing the progression of aging. In this review, data have been collected on the hallmarks and their relative contributions to aging and supplemented with in vitro and in vivo antiaging research experiments. It is the intention of this article to highlight the most important antiaging strategies that researchers have proposed, including preventive measures, systemic therapeutic agents, and invasive procedures, that will promote healthy aging and increase human life expectancy with decreased side effects.

The Anticancer Potential of Plant-Derived Nutraceuticals via the Modulation of Gene Expression

Current studies show that approximately one-third of all cancer-related deaths are linked to diet and several cancer forms are preventable with balanced nutrition, due to dietary compounds being able to reverse epigenetic abnormalities. An appropriate diet in cancer patients can lead to changes in gene expression and enhance the efficacy of therapy. It has been demonstrated that nutraceuticals can act as powerful antioxidants at the cellular level as well as anticarcinogenic agents. This review is focused on the best studies on worldwide-available plant-derived nutraceuticals: curcumin, resveratrol, sulforaphane, indole-3-carbinol, quercetin, astaxanthin, epigallocatechin-3-gallate, and lycopene. These compounds have an enhanced effect on epigenetic changes such as histone modification via HDAC (histone deacetylase), HAT (histone acetyltransferase) inhibition, DNMT (DNA methyltransferase) inhibition, and non-coding RNA expression. All of these nutraceuticals are reported to positively modulate the epigenome, reducing cancer incidence. Furthermore, the current review addresses the issue of the low bioavailability of nutraceuticals and how to overcome the drawbacks related to their oral administration. Understanding the mechanisms by which nutraceuticals influence gene expression will allow their incorporation into an “epigenetic diet” that could be further capitalized on in the therapy of cancer.

The Effects of Resveratrol-Rich Extracts of Vitis vinifera Pruning Waste on HeLa, MCF-7 and MRC-5 Cells: Apoptosis, Autophagia and Necrosis Interplay

Resveratrol is a well-studied plant-derived molecule in cancer biology, with a plethora of documented in vitro effects. However, its low bioavailability and toxicity risk hamper its wider use. In this study, vine shoots after pruning were used as a source of resveratrol (RSV). The activity of subcritical water extract (SWE) and dry extract (DE) is examined on three cell lines: HeLa, MCF-7 and MRC-5. The cytotoxic effect is assessed by the MTT test and EB/AO staining, levels of apoptosis are determined by Annexin V assay, autophagia by ULK-1 expression using Western blot and NF-kB activation by p65 ELISA. Our results show that both resveratrol-rich extracts (DE, SWE) have a preferential cytotoxic effect on malignant cell lines (HeLa, MCF-7), and low cytotoxicity on non-malignant cells in culture (MRC-5). Further experiments indicate that the investigated malignant cells undergo different cell death pathways. MCF-7 cells died preferentially by apoptosis, while the HeLa cells died most likely by necrosis (possibly ferroptosis). Protective autophagia is diminished upon treatment with DE in both HeLa and MCF-7 cells, while SWE does not influence the level of autophagia. The extracts are effective even at low concentrations (below IC50) in the activation of NF-kB (p65 translocation).

Resveratrol: A potential therapeutic natural polyphenol for neurodegenerative diseases associated with mitochondrial dysfunction

Most polyphenols can cross blood-brain barrier, therefore, they are widely utilized in the treatment of various neurodegenerative diseases (ND). Resveratrol, a natural polyphenol contained in blueberry, grapes, mulberry, etc., is well documented to exhibit potent neuroprotective activity against different ND by mitochondria modulation approach. Mitochondrial function impairment is the most common etiology and pathological process in various neurodegenerative disorders, viz. Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis. Nowadays these ND associated with mitochondrial dysfunction have become a major threat to public health as well as health care systems in terms of financial burden. Currently available therapies for ND are limited to symptomatic cures and have inevitable toxic effects. Therefore, there is a strict requirement for a safe and highly effective drug treatment developed from natural compounds. The current review provides updated information about the potential of resveratrol to target mitochondria in the treatment of ND.

Potential therapeutic effects of natural compounds targeting autophagy to alleviate podocyte injury in glomerular diseases

Podocyte injury is a common cause of proteinuric kidney diseases. Uncontrollable progressive podocyte loss accelerates glomerulosclerosis and increases the risk of end-stage renal disease. To date, owing to the complex pathological mechanism, effective therapies for podocyte injury have been limited. Accumulating evidence supports the indispensable role of autophagy in the maintenance of podocyte homeostasis. A variety of natural compounds and their derivatives have been found to regulate autophagy through multiple targets, including promotes nuclear transfer of transcription factor EB and lysosomal repair. Here, we reviewed the recent studies on the use of natural compounds and their derivatives as autophagy regulators and discussed their potential applications in ameliorating podocyte injury. Several known natural compounds with autophagy-regulatory properties, such as quercetin, silibinin, kaempferol, and artemisinin, and their medical uses were also discussed. This review will help in improving the understanding of the podocyte protective mechanism of natural compounds and promote their development for clinical use.

AP2M1 mediates autophagy-induced CLDN2 (claudin 2) degradation through endocytosis and interaction with LC3 and reduces intestinal epithelial tight junction permeability

The intestinal epithelial tight junctions (TJs) provide barrier against paracellular permeation of lumenal antigens. Defects in TJ barrier such as increased levels of pore-forming TJ protein CLDN2 (claudin-2) is associated with inflammatory bowel disease. We have previously reported that starvation-induced macroautophagy/autophagy enhances the TJ barrier by degrading pore-forming CLDN2. In this study, we examined the molecular mechanism underlying autophagy-induced CLDN2 degradation. CLDN2 degradation was persistent in multiple modes of autophagy induction. Immunolocalization, membrane fractionation, and pharmacological inhibition studies showed increased clathrin-mediated CLDN2 endocytosis upon starvation. Inhibition of clathrin-mediated endocytosis negated autophagy-induced CLDN2 degradation and enhancement of the TJ barrier. The co-immunoprecipitation studies showed increased association of CLDN2 with clathrin and adaptor protein AP2 (AP2A1 and AP2M1 subunits) as well as LC3 and lysosomes upon starvation, signifying the role of clathrin-mediated endocytosis in autophagy-induced CLDN2 degradation. The expression and phosphorylation of AP2M1 was increased upon starvation. In-vitro, in-vivo (mouse colon), and ex-vivo (human colon) inhibition of AP2M1 activation prevented CLDN2 degradation. AP2M1 knockout prevented autophagy-induced CLDN2 degradation via reduced CLDN2-LC3 interaction. Site-directed mutagenesis revealed that AP2M1 binds to CLDN2 tyrosine motifs (YXXФ) (67-70 and 148-151). Increased baseline expression of CLDN2 and TJ permeability along with reduced CLDN2-AP2M1-LC3 interactions in ATG7 knockout cells validated the role of autophagy in modulation of CLDN2 levels. Acute deletion of Atg7 in mice increased CLDN2 levels and the susceptibility to experimental colitis. The autophagy-regulated molecular mechanisms linking CLDN2, AP2M1, and LC3 may provide therapeutic tools against intestinal inflammation.Abbreviations: Amil: amiloride; AP2: adaptor protein complex 2; AP2A1: adaptor related protein complex 2 subunit alpha 1; AP2M1: adaptor related protein complex 2 subunit mu 1; ATG7: autophagy related 7; CAL: calcitriol; Cas9: CRISPR-associated protein 9; Con: control; CPZ: chlorpromazine; DSS: dextran sodium sulfate; EBSS: Earle's balanced salt solution; IBD: inflammatory bowel disease; TER: trans-epithelial resistance; KD: knockdown; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MβCD: Methyl-β-cyclodextrin; MET: metformin; MG132: carbobenzoxy-Leu-Leu-leucinal; MTOR: mechanistic target of rapamycin kinase; NT: non target; RAPA: rapamycin; RES: resveratrol; SMER: small-molecule enhancer 28; SQSTM1: sequestosome 1; ST: starvation; ULK1: unc-51 like autophagy activating kinase 1; WT: wild type.

Improving Photodynamic Therapy Anticancer Activity of a Mitochondria-Targeted Coumarin Photosensitizer Using a Polyurethane-Polyurea Hybrid Nanocarrier

Integration of photosensitizers (PSs) within nanoscale delivery systems offers great potential for overcoming some of the "Achiles' heels" of photodynamic therapy (PDT). Herein, we have encapsulated a mitochondria-targeted coumarin PS into amphoteric polyurethane-polyurea hybrid nanocapsules (NCs) with the aim of developing novel nanoPDT agents. The synthesis of coumarin-loaded NCs involved the nanoemulsification of a suitable prepolymer in the presence of a PS without needing external surfactants, and the resulting small nanoparticles showed improved photostability compared with the free compound. Nanoencapsulation reduced dark cytotoxicity of the coumarin PS and significantly improved in vitro photoactivity with red light toward cancer cells, which resulted in higher phototherapeutic indexes compared to free PS. Importantly, this nanoformulation impaired tumoral growth of clinically relevant three-dimensional multicellular tumor spheroids. Mitochondrial photodamage along with reactive oxygen species (ROS) photogeneration was found to trigger autophagy and apoptotic cell death of cancer cells.

Resveratrol sensitizes breast cancer to PARP inhibitor, talazoparib through dual inhibition of AKT and autophagy flux

The efficacy of poly (ADP-ribose) polymerase inhibitors (PARPi) is largely limited to the homologous recombination (HR) deficient cancers. Therefore, there is a necessity to explore novel drug combinations with PARPi to enhance its anti-cancer activity in HR-proficient cancers. By analysing the patient data in cBioPortal, we found copy number amplification of PARP1 in ∼ 22.8% of breast cancers. PARP1 upregulation has been correlated with unfavourable outcome with PARPi treatment. To overcome this adversity, we explored the effect of resveratrol, a natural molecule chemosensitizer, in enhancing the effects of the third generation PARPi, talazoparib (BMN673), against breast adenocarcinoma. Our results show that resveratrol effectively sensitized talazoparib induced cell death in HR proficient and BRCA wild-type breast cancer cells in vitro. Mechanistically, resveratrol caused dysregulation of cell cycle and enhanced talazoparib-induced double strand breaks (DSBs), leading to abnormal mitotic progression culminating in mitotic catastrophe. Intriguingly, our results showed potential of resveratrol in dual-inhibition of AKT-signalling and autophagy flux to impair HR-mediated DSB-repair in breast cancer cells. By using EGFP-LC3 and tf-LC3 (mRFP-EGFP-LC3) expressing breast cancer cells, we found that resveratrol attenuates fusion of autophagosome and lysosome though induction of lysosomal-membrane-permeabilization (LMP). The combination of resveratrol and talazoparib effectively reduced cell proliferation in the high-density cell proliferation assay and also led to tumour volume reduction in vivo pre-clinical SCID-mice model. The combination caused no or minimal cytotoxicity in three different normal cell lines in vitro. Taken together, our work proposes the usage of resveratrol as a chemosensitizer along with talazoparib for targeting HR-proficient breast cancers in clinical settings.

Nano-Resveratrol: A Promising Candidate for the Treatment of Renal Toxicity Induced by Doxorubicin in Rats Through Modulation of Beclin-1 and mTOR

Background: Although doxorubicin (DXR) is one of the most used anticancer drugs, it can cause life-threatening renal damage. There has been no effective treatment for DXR-induced renal damage until now.

Aim: This work aims at examining the potential impact of nano-resveratrol (N-Resv), native resveratrol (Resv), and their combination with carvedilol (Card) against DXR-induced renal toxicity in rats and to investigate the mechanisms through which these antioxidants act to ameliorate DXR nephrotoxicity. Method: DXR was administered to rats (2 mg/kg, i.p.) twice weekly over 5 weeks. The antioxidants in question were taken 1 week before the DXR dose for 6 weeks.

Results: DXR exhibited an elevation in serum urea, creatinine, renal lipid peroxide levels, endoglin expression, kidney injury molecule-1 (KIM-1), and beclin-1. On the other hand, renal podocin and mTOR expression and GSH levels were declined. In addition, DNA fragmentation was markedly increased in the DXR-administered group. Treatment with either Resv or N-Resv alone or in combination with Card ameliorated the previously measured parameters.

Conclusion: N-Resv showed superior effectiveness relative to Resv in most of the measured parameters. Histopathological examination revealed amelioration of renal structural and cellular changes after DXR by Card and N-Resv, thus validating the previous biochemical and molecular results.

SIRT4 Is Highly Expressed in Retinal Müller Glial Cells

Sirtuin 4 (SIRT4) is one of seven mammalian sirtuins that possesses ADP-ribosyltransferase, lipoamidase and deacylase activities and plays indispensable role in metabolic regulation. However, the role of SIRT4 in the retina is not clearly understood. The purpose of this study was to explore the location and function of SIRT4 in the retina. Therefore, immunofluorescence was used to analyze the localization of SIRT4 in rat, mouse and human retinas. Western blotting was used to assess SIRT4 and glutamine synthetase (GS) protein expression at different developmental stages in C57BL/6 mice retinas. We further analyzed the retinal structure, electrophysiological function and the expression of GS protein in SIRT4-deficient mice. Excitotoxicity was caused by intravitreal injection of glutamate (50 nmol) in mice with long-term intraperitoneal injection of resveratrol (20 mg/Kg), and then retinas were subjected to Western blotting and paraffin section staining to analyze the effect of SIRT4 on excitotoxicity. We show that SIRT4 co-locates with Müller glial cell markers (GS and vimentin). The protein expression pattern of SIRT4 was similar to that of GS, and both increased with development. There were no significant retinal structure or electrophysiological function changes in 2-month SIRT4-deficient mice, while the expression of GS protein was decreased. Moreover, long-term administration of resveratrol can upregulate the expression of SIRT4 and GS while reducing the retinal injury caused by excessive glutamate. These results suggest that SIRT4 is highly expressed in retinal Müller glial cells and is relevant to the expression of GS. SIRT4 does not appear to be essential in retinal development, but resveratrol, as an activator of SIRT4, can upregulate GS protein expression and protect the retina from excitotoxicity.