Resveratrol attenuates myocardial hypoxia/reoxygenation-induced cell apoptosis through DJ-1-mediated SIRT1-p53 pathway

DJ-1: Potential target for treatment of myocardial ischemia-reperfusion injury

Ischemic heart disease (IHD) is a significant global health concern, resulting in high rates of mortality and disability among patients. Although coronary blood flow reperfusion is a key treatment for IHD, it often leads to acute myocardial ischemia-reperfusion injury (IRI). Current intervention strategies have limitations in providing adequate protection for the ischemic myocardium. DJ-1, originally known as a Parkinson's disease related protein, is a highly conserved cytoprotective protein. It is involved in enhancing mitochondrial function, scavenging reactive oxygen species (ROS), regulating autophagy, inhibiting apoptosis, modulating anaerobic metabolism, and exerting anti-inflammatory effects. DJ-1 is also required for protective strategies, such as ischemic preconditioning, ischemic postconditioning, remote ischemic preconditioning and pharmacological conditioning. Therefore, DJ-1 emerges as a potential target for the treatment of myocardial IRI. Our comprehensive review delves into its protective mechanisms in myocardial IRI and the structural foundations underlying its functions.

Network pharmacology and molecular docking to explore the treatment potential and molecular mechanism of Si-Miao decoction against gouty arthritis

Gouty arthritis (GA) is a common metabolic rheumatological disease. Si-Miao decoction has therapeutic effects on GA. In our study, we investigated the mechanism of Si-Miao decoction against GA using network pharmacology and molecular docking analytical methods. The Traditional Chinese Medicine Systems Pharmacology Database was used as the basis for screening the main targets and agents of the Si-Miao decoction, and the Genecards, OMIM, and Drugbank databases were used to screen GA-related targets. They were analyzed using Venn with the drug targets to obtain the intersection targets. We used Cytoscape 3.9.1 to draw the "Drugs-Compounds-Targets" network and the String database for creative protein-protein interaction networks of target genes and filtered core targets. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to analyze the core targets. Molecular docking was performed using AutoDockTools to predict the binding capacity between nuclear targets and active components in the Si-Miao decoction. A total of 50 chemically active components containing 53 common targets of Si-Miao decoction anti-GA and 53 potential drug target proteins were identified. Core targets, namely, TNF, STAT3, SRC, PPARG, TLR4, PTGS2, MMP9, RELA, TGFB1, and SIRT1, were obtained through PPI network analysis. GO and KEGG analyses showed that the mechanism of anti-GA in Si-Miao decoction may proceed by regulating biological processes such as inflammatory factor levels, cell proliferation, apoptosis, and lipid and glucose metabolism, and modulating the NOD-like receptor signaling pathway, IL-17 signaling pathway, TNF signaling pathway, NF-kappa B signaling pathway, and Toll-like receptor signaling pathway. We further screened the core targets, including PTGS2, MMP9, and PPAGR, as receptor proteins based on their degree value and molecular docking with the main active compounds in Si-Miao decoction, and found that baicalein had high affinity. In conclusion, Si-Miao decoction, through anti-inflammatory, apoptosis-regulating, and anti-oxidative stress action mechanisms in the treatment of GA.

SIRT1 is a regulator of autophagy: Implications for the progression and treatment of myocardial ischemia-reperfusion

SIRT1 is a highly conserved nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylase. It is involved in the regulation of various pathophysiological processes, including cell proliferation, survival, differentiation, autophagy, and oxidative stress. Therapeutic activation of SIRT1 protects the heart and cardiomyocytes from pathology-related stress, particularly myocardial ischemia/reperfusion (I/R). Autophagy is an important metabolic pathway for cell survival during energy or nutrient deficiency, hypoxia, or oxidative stress. Autophagy is a double-edged sword in myocardial I/R injury. The activation of autophagy during the ischemic phase removes excess metabolic waste and helps ensure cardiomyocyte survival, whereas excessive autophagy during reperfusion depletes the cellular components and leads to autophagic cell death. Increasing research on I/R injury has indicated that SIRT1 is involved in the process of autophagy and regulates myocardial I/R. SIRT1 regulates autophagy through various pathways, such as the deacetylation of FOXOs, ATGs, and LC3. Recent studies have confirmed that SIRT1-mediated autophagy plays different roles at different stages of myocardial I/R injury. By targeting the mechanism of SIRT1-mediated autophagy at different stages of I/R injury, new small-molecule drugs, miRNA activators, or blockers can be developed. For example, resveratrol, sevoflurane, quercetin, and melatonin in the ischemic stage, coptisine, curcumin, berberine, and some miRNAs during reperfusion, were involved in regulating the SIRT1-autophagy axis, exerting a cardioprotective effect. Here, we summarize the possible mechanisms of autophagy regulation by SIRT1 in myocardial I/R injury and the related molecular drug applications to identify strategies for treating myocardial I/R injury.

Perfluorooctanoic acid exposure leads to defect in follicular development through disrupting the mitochondrial electron transport chain in granulosa cells

Perfluorooctanoic acid (PFOA) is a persistent environmental pollutant that can impair ovarian function, while the underlying mechanism is not fully understood, and effective treatments are lacking. In this study, we established a mouse model of PFOA exposure induced by drinking water and found that PFOA exposure impaired follicle development, increased apoptosis of granulosa cells (GCs), and hindered normal follicular development in a 3D culture system. RNA-seq analysis revealed that PFOA disrupted oxidative phosphorylation in ovaries by impairing the mitochondrial electron transport chain. This resulted in reduced mitochondrial membrane potential and increased mitochondrial reactive oxygen species (mtROS) in isolated GCs or KGN cells. Resveratrol, a mitochondrial nutrient supplement, could improve mitochondrial function and restore normal follicular development by activating FoxO1 through SIRT1/PI3K-AKT pathway. Our results indicate that PFOA exposure impairs mitochondrial function in GCs and affects follicle development. Resveratrol can be a potential therapeutic agent for PFOA-induced ovarian dysfunction.

Relating aging and autophagy: a new perspective towards the welfare of human health

The most common factor that contributes to aging is the loss of proteostasis, resulting in an excess amount of non-functional/damaged proteins. These proteins lead to various age-associated phenotypes such as cellular senescence and dysfunction in the nutrient-sensing pathways. Despite the various factors that can contribute to aging, it is still a process that can be changed. According to recent advances in the field of biology, the ability to alter the pathways that are involved in aging can improve the lifespan of a person. Autophagy is a process that helps in preserving survival during stressful situations, such as starvation. It is a common component of various anti-aging interventions, including those that target the insulin/IGF-1 and rapamycin signaling pathways. It has been shown that altered autophagy is a common feature of old age and its impaired regulation could have significant effects on the aging process. This review aims to look into the role of autophagy in aging and how it can be used to improve one's health.

The Role of P53 in Myocardial Ischemia-Reperfusion Injury

PURPOSE

P53 is one of the key tumor suppressors. In normal cells, p53 is maintained at low levels by the ubiquitination of the ubiquitinated ligase MDM2. In contrast, under stress conditions such as DNA damage and ischemia, the interaction between p53 and MDM2 is blocked and activated by phosphorylation and acetylation, thereby mediating the trans-activation of p53 through its target genes to regulate a variety of cellular responses. Previous studies have shown that the expression of p53 is negligible in normal myocardium, tends to increase in myocardial ischemia and is maximally induced in ischemia-reperfused myocardium, demonstrating a possible key role of p53 in the development of MIRI. In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and describe the therapeutic agents targeting the relevant targets to provide new strategies for the prevention and treatment of MIRI.

METHODS

We collected 161 relevant papers mainly from Pubmed and Web of Science (search terms "p53" and "myocardial ischemia-reperfusion injury"). After that, we selected pathway studies related to p53 and classified them according to their contents. We eventually analyzed and summarized them.

RESULTS AND CONCLUSION

In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and validate its status as an important intermediate affecting MIRI. On the one hand, p53 is regulated and modified by multiple factors, especially non-coding RNAs; on the other hand, p53 regulates apoptosis, programmed necrosis, autophagy, iron death and oxidative stress in MIRI through multiple pathways. More importantly, several studies have reported medications targeting p53-related therapeutic targets. These medications are expected to be effective options for the alleviation of MIRI, but further safety and clinical studies are needed to convert them into clinical applications.

Resveratrol inhibits autophagy against myocardial ischemia-reperfusion injury through the DJ-1/MEKK1/JNK pathway

Resveratrol (RES), a natural polyphenolic compound found in red wine and grape skins, has attracted significant attention due to its cardioprotective properties. DJ-1, a multifunctional protein that participated in transcription regulation and antioxidant defense, was shown to provide a significant protective impact in cardiac cells treated with ischemia-reperfusion. We created a myocardial ischemia-reperfusion (I/R) model in vivo and in vitro by ligating the left anterior descending branch of rats and subjecting H9c2 cells to anoxia/reoxygenation (A/R) to investigate whether RES reduces myocardial ischemia-reperfusion injury by upregulating DJ-1. We discovered that RES dramatically enhanced cardiac function in rats with I/R. Subsequently, we found that RES prevented the rise in autophagy (P62 degradation and LC3-II/LC3-I increase) induced by cardiac ischemia-reperfusion in vitro and in vivo. Notably, the autophagic agonist rapamycin (RAPA) eliminated RES-induced cardioprotective effects. In addition, Further data showed that RES significantly increased the expression of DJ-1 in the myocardium with the treatment of I/R. At the same time, pretreatment with RES reduced phosphorylation of MAPK/ERK kinase kinase 1 (MEKK1) and Jun N-terminal Kinase (JNK) stimulated by cardiac ischemia-reperfusion, and Beclin-1 mRNA and protein levels while decreasing lactate dehydrogenase (LDH) and improving cell viability. However, the lentiviral shDJ-1 and JNK agonist anisomycin disrupted the effects of RES. In summary, RES could inhibit autophagy against myocardial ischemia-reperfusion injury through DJ-1 modulation of the MEKK1/JNK pathway, providing a novel therapeutic strategy for cardiac homeostasis.

Naringin against doxorubicin-induced hepatotoxicity in mice through reducing oxidative stress, inflammation, and apoptosis via the up-regulation of SIRT1

Clinical application of doxorubicin is limited because of its potential side effects. The present study examined whether naringin had protective actions on doxorubicin-induced liver injury. Male BALB/c mice and alpha mouse liver 12 (AML-12) cells were used in this paper. The results showed that AML-12 cells treated with naringin significantly reduced cell injury, reactive oxygen species release and apoptosis level; Moreover, naringin notably alleviated liver injury by decreasing aspartate transaminase, alanine transaminase and malondialdehyde, and increasing superoxide dismutase, glutathione and catalase levels. Mechanism researches indicated that naringin increased the expression levels of sirtuin 1 (SIRT1), and inhibited the downstream inflammatory, apoptotic and oxidative stress signaling pathways. Further validation was obtained by knocking down SIRT1 in vitro, which proved the effects of naringin on doxorubicin-induced liver injury. Therefore, naringin is a valuable lead compound for preventing doxorubicin-induced liver damage by reducing oxidative stress, inflammation, and apoptosis via up-regulation of SIRT1.

Apigenin alleviates oxidative stress-induced myocardial injury by regulating SIRT1 signaling pathway

Apigenin is a natural flavonoid which is widely found in vegetables and fruits. However, the mechanism of apigenin in oxidative stress-induced myocardial injury has not been fully elucidated. We established an isoproterenol (Iso)-induced myocardial injury mouse model and a hypoxia/reoxygenation (H/R)-induced H9c2 cell injury model, followed by pretreatment with apigenin to explore its protective effects. Apigenin can significantly alleviate isoproterenol-induced oxidative stress, cell apoptosis and myocardial remodeling in vivo. Apigenin pretreatment can also significantly improve cardiomyocyte morphology, decrease H/R induced oxidative stress, and attenuate cell apoptosis and inflammation in vitro. Further mechanism study revealed that apigenin treatment reversed isoprenaline and H/R-induced decrease of Sirtuin1 (SIRT1). Molecular docking results proved that apigenin can form hydrogen bond with 230 Glu, a key site of SIRT1 activation, indicating that apigenin is an agonist of SIRT1. Moreover, SIRT1 knockdown by siRNA significantly reversed the protective effect of apigenin in H/R-induced myocardial injury. In conclusion, apigenin protects cardiomyocyte function from oxidative stress-induced myocardial injury by modulating SIRT1 signaling pathway, which provides a new potential therapeutic natural compound for the clinical treatment of cardiovascular diseases.

Garcinol protects SH-SY5Y cells against MPP+-induced cell death by activating DJ-1/SIRT1 and PGC-1α mediated antioxidant pathway in sequential stimulation of p-AMPK mediated autophagy

Parkinson's disease (PD), a chronic and progressive neurodegenerative disease, can reduce the population of dopaminergic neurons in the substantia nigra. The cause of this neuronal death remains unclear. 1-Methyl-4-phenylpyridinium ion (MPP+) is a potent neurotoxin that can destroy dopaminergic (DA) neurons and promote PD. Garcinol, a polyisoprenylated benzophenone derivative, was extracted from Garcinia indica and is an important active compound it has been used as an anticancer, antioxidant, and anti-inflammatory, agent and it can suppress reactive oxygen species (ROS) mediated cell death in a PD model. Human neuroblastoma (SH-SY5Y) cells (1 × 10⁵  cells) were treated with MPP+ (1 mM) for 24 h to induce cellular ROS production. The formation of ROS was suppressed by pretreatment with different concentrations of garcinol (0.5 and 1.0 μM) for 3 h in SH-SY5Y cells. The present study found that MPP+ treatment increased the formation of reactive oxygen species (ROS), and the increased ROS began to promote cell death in SH-SY5Y cells. However, our natural compound garcinol effectively blocked MPP+-mediated ROS formation by activating the DJ-1/SIRT1 and PGC-1α mediated antioxidant pathway. Further findings indicate that the activated SIRT1 can also regulate p-AMPK-mediated autophagy to protect the neurons from the damage it concludes that garcinol sub-sequential regulates intracellular autophagy in this model, and the productive efficacy of garcinol was confirmed by western blot analysis and MitoSOX DCFDA and MTT assays. The results showed garcinol increased protection due to the prevention of MPP+-induced ROS and the promotion of cell survival.

Novel pathways of fluoride-induced hepatotoxicity: P53-dependent ferroptosis induced by the SIRT1/FOXOs pathway and Nrf2/HO-1 pathway

Fluoride (F) is an environmental pollutant that continues to threaten human health. Long-term or excessive fluoride exposure can cause a series of acute or chronic systemic and organ-specific diseases. The liver is considered to be one of the important target organs of fluoride poisoning, however, the specific cause of liver damage caused by fluoride is still unclear. In the present study, we identified ferroptosis as a key mechanism of fluoride-induced liver injury. Under fluorosis conditions, lipid peroxidation levels in the liver are significantly increased and iron overload is induced. Combined transcriptomic and metabolomic analysis revealed that activation of the SIRT1/FOXOs pathway is one of the main causes of fluorosis-induced liver damage. Further analysis by in vitro experiments showed that the SIRT1/FOXOs pathway can cause the activation of the Nrf2/HO-1 pathway under the condition of fluorosis, and can activate the P53-dependent ferroptosis pathway, leading to the occurrence of lipid peroxidation and iron accumulation, ultimately leading to ferroptosis. Our study provides insight into the mechanism of fluoride-induced liver injury, and our results also provide strategies for treatment to alleviate liver injury caused by fluorosis.

Extracellular vesicles DJ-1 derived from hypoxia-conditioned hMSCs alleviate cardiac hypertrophy by suppressing mitochondria dysfunction and preventing ATRAP degradation

BACKGROUND

As a pathological myocardial remodeling process in a variety of cardiovascular diseases, cardiac hypertrophy still has no effective treatment. Human mesenchymal stem cells (hMSCs) derived extracellular vesicles (EVs) has been recognized as a promising treatment strategy for cardiac disease.

METHODS

In this study, the inhibitory effects on cardiac hypertrophy are compared between normoxia-conditioned hMSC-derived EVs (Nor-EVs) and hypoxia-conditioned hMSC-derived EVs (Hypo-EVs) in neonatal rat cardiomyocytes (NRCMs) after angiotensin II (Ang II) stimulation and in a mouse model of transverse aortic constriction (TAC).

RESULTS

We demonstrate that Hypo-EVs exert an increased inhibitory effect on cardiac hypertrophy compared with Nor-EVs. Parkinson disease protein 7 (PARK7/DJ-1) is identify as a differential protein between Nor-EVs and Hypo-EVs by quantitative proteomics analysis. Results show that DJ-1, which is rich in Hypo-EVs, alleviates mitochondrial dysfunction and excessive mitochondrial reactive oxygen species (mtROS) production as an antioxidant. Mechanistic studies demonstrate for the first time that DJ-1 may suppress cardiac hypertrophy by inhibiting the activity of proteasome subunit beta type 10 (PSMB10) through a direct physical interaction. This interaction can inhibit angiotensin II type 1 receptor (AT1R)-mediated signaling pathways resulting in cardiac hypertrophy through alleviating ubiquitination degradation of AT1R-associated protein (ATRAP).

CONCLUSIONS

When taken together, our study suggests that Hypo-EVs have significant potential as a novel therapeutic agent for the treatment of cardiac hypertrophy.

Sirtuin 1-Activating Compounds: Discovery of a Class of Thiazole-Based Derivatives

Sirtuin 1 (SIRT1) is a NAD⁺-dependent deacetylase implicated in various biological and pathological processes, including cancer, diabetes, and cardiovascular diseases. In recent years, SIRT1-activating compounds have been demonstrated to exert cardioprotective effects. Therefore, this enzyme has become a feasible target to treat cardiovascular diseases, and many SIRT1 activators, of a natural or synthetic origin, have been identified. In the present work, we developed thiazole-based SIRT1 activators, which showed remarkably higher SIRT1 activation potencies compared with those of the reference compound resveratrol when tested in enzymatic assays. Thiazole 8, a representative compound of this series, was also subjected to further pharmacological investigations, where it was proven to reduce myocardial damage induced by an in vivo occlusion/reperfusion event, thus confirming its cardioprotective properties. In addition, the cardioprotective effect of compound 8 was significantly higher than that of resveratrol. Molecular modeling studies suggest the binding mode of these derivatives within SIRT1 in the presence of the p53-AMC peptide. These promising results could pave the way to further expand and optimize this chemical class of new and potent SIRT1 activators as potential cardioprotective agents.

Salidroside, a phenyl ethanol glycoside from Rhodiola crenulata, orchestrates hypoxic mitochondrial dynamics homeostasis by stimulating Sirt1/p53/Drp1 signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Rhodiola crenulata is clinically used to combat hypobaric hypoxia brain injury at high altitude with the function of invigorating Qi and promoting blood circulation in Tibetan medicine. Salidroside (Sal), an active compound identified from Rhodiola species, has been shown to exert neuroprotective effects against hypoxic brain injury. However, its mitochondrial protective mechanisms remain largely unknown.

AIM OF THE STUDY

The present study aimed to explore the mitochondrial protection of Sal and the involved mechanisms related to mitochondrial dynamics homeostasis on hypoxia-induced injury of HT22 cells.

MATERIALS AND METHODS

Hypoxic condition was performed as cells cultured in a tri-gas incubator with 1% O₂, 5% CO₂ and 94% N₂. We firstly investigated the effects of different concentrations of Sal on the viability of normal or hypoxic HT22 cells. Whereafter, the levels of lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), adenosine triphosphate (ATP) and Na⁺-K⁺-ATPase were tested by commercial kits. Meanwhile, mitochondrial superoxide, intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were determined by specific labeled probes. Mitochondrial morphology was detected by mito-tracker green with confocal microscopy. Additionally, the potential interactions of Sal with Sirt1/p53/Drp1 signaling pathway-related proteins were predicted and tested by molecular docking and localized surface plasmon resonance (LSPR) techniques, respectively. Furthermore, the protein levels of Sirt1, p53, ac-p53, Drp1, p-Drp1(s616), Fis1 and Mfn2 were estimated by western blot analysis.

RESULTS

Sal alleviated hypoxia-induced oxidative stress in HT22 cells as evidenced by increased cell viability and SOD activity, while decreased LDH release and MDA content. The protected mitochondrial function by Sal treatment was indicated by the increases of ATP level, Na⁺-K⁺-ATPase activity and MMP. Miraculously, Sal reduced hypoxia-induced mitochondrial fission, while increased mitochondrial tubular or linear morphology. The results of molecular docking and LSPR confirmed the potential binding of Sal to proteins Sirt1, p53, Fis1 and Mfn2 with affinity values 1.38 × 10^-2, 5.26 × 10^-3, 6.46 × 10^-3 and 7.26 × 10^-3 KD, respectively. And western blot analysis further demonstrated that Sal memorably raised the levels of Sirt1 and Mfn2, while decreased the levels of ac-p53, Drp1, p-Drp1 (s616) and Fis1.

CONCLUSION

Collectively, our data confirm that Sal can maintain mitochondrial dynamics homeostasis by activating the Sirt1/p53/Drp1 signaling pathway.

Neural stem cell secretome exerts a protective effect on damaged neuron mitochondria in Parkinson's disease model

Parkinson's disease (PD) is a common neurodegenerative disease. The main pathological changes are the loss of dopaminergic neurons and the formation of Lewy bodies. There is still no effective cure for PD, and cell replacement therapy has entered a bottleneck period due to tumorigenicity and rejection. Therefore, stem cell secretome has received widespread attention. However, the exploration of the secretome components of neural stem cells (NSCs) is still in its infancy. In this study, 6-hydroxydopamine (6-OHDA) was used to establish a PD rat model in vito and the PC12 cell-damaged model in vitro. The results indicated that the injection of neural stem cell-conditioned medium (NSC-CM) into the striatum and substantia nigra could improve the motor and non-motor deficits of PD rats and rescue the loss of dopaminergic neurons. In addition, NSC-CM alleviated 6-OHDA-induced apoptosis of PC12 cells, reduced the level of oxidative stress, and improved mitochondrial dysfunction in vitro. Parkinson disease protein 7 (Park7) was found in NSC-CM by Liquid chromatography-tandem mass spectrometry (LC-MS/MS), and it may be related to the protective effect of NSC-CM on 6-OHDA-injured neurons through Sirt1 pathway. In conclusion, NSC secretome might provide new ideas for the treatment of PD.

SIRT1/NFκB pathway mediates anti-inflammatory and anti-apoptotic effects of rosmarinic acid on in a mouse model of nonalcoholic steatohepatitis (NASH)

Nonalcoholic steatohepatitis (NASH) is considered as a common liver disease. SIRT1, a pivotal sensor, controls activation of metabolic, inflammatory and apoptotic pathways. Rosmarinic acid (RA) has positive effects on the liver injuries; nevertheless, its mechanisms are not completely studied. The aim of this study was to explore the role of rosmarinic acid on the pathways involved by SIRT1 for amelioration of a mouse model of NASH. To do this, C57/BL6 mice were divided into four equal groups (6 in each group). Animals received saline and rosmarinic acid as the control groups. NASH was induced by methionine-choline-deficient (MCD) diet. In the NASH + RA group, Rosmarinic acid was injected daily in mice fed on an MCD diet. Rosmarinic acid decreased plasma triglyceride, cholesterol, liver Steatosis and oxidative stress. Rosmarinic acid administration also increased SIRT1, Nrf2 and PPARα and decreased SREBP1c, FAS, NFκB and caspase3 expressions. Moreover, TNFα, IL6, P53, Bax/Bcl2 ratio and caspase3 expressions decreased. Our study demonstrated that remarkable effects of rosmarinic acid on the mice with NASH might be due to activation of SIRT1/Nrf2, SIRT1/NFκB and SIRT1/PPARα pathways, which alleviate hepatic steatosis, oxidative stress, inflammation and apoptosis.

Resveratrol Attenuate Myocardial Injury by Inhibiting Ferroptosis Via Inducing KAT5/GPX4 in Myocardial Infarction

Myocardial infarction (MI) is a coronary artery-related disease and ranks as the leading cause of sudden death globally. Resveratrol (Res) is a bioactive component and has presented antioxidant, anti-inflammatory and anti-microbial properties. However, the effect of Res on ferroptosis during MI progression remains elusive. Here, we aimed to explore the function of Res in the regulation of ferroptosis and myocardial injury in MI. We observed that the treatment of Res attenuated the MI-related myocardium injury and fibrosis in the rats. The expression of collagen 1 and α-SMA was induced in MI rats, in which the treatment of Res could decrease the expression. Treatment of Res suppressed the levels of IL-6 and IL-1β in MI rats. The GSH levels were inhibited and MDA, lipid ROS, and Fe²⁺ levels were induced in MI rats, in which the treatment of Res could reverse the phenotypes. Meanwhile, the expression of GPX4 and SLC7A11 was reduced in MI rats, while the treatment of Res could rescue the expression in the model. Meanwhile, Res relieved oxygen-glucose deprivation (OGD)-induced cardiomyocyte injury. Importantly, Res repressed OGD-induced cardiomyocyte ferroptosis in vitro. Mechanically, we identified that Res was able to enhance GPX4 expression by inducing KAT5 expression. We confirmed that KAT5 alleviated OGD-induced cardiomyocyte injury and ferroptosis. The depletion of KAT5 or GPX4 could reverse the effect of Res on OGD-induced cardiomyocyte injury. Thus, we concluded that Res attenuated myocardial injury by inhibiting ferroptosis via inducing KAT5/GPX4 in myocardial infarction. Our finding provides new evidence of the potential therapeutic effect of Res on MI by targeting ferroptosis.

High-content analysis of microRNAs involved in the phenotype regulation of vascular smooth muscle cells

In response to vascular injury vascular smooth muscle cells (VSMCs) alternate between a differentiated (contractile) and a dedifferentiated (synthetic) state or phenotype. Although parts of the signaling cascade regulating the phenotypic switch have been described, the role of miRNAs is still incompletely understood. To systematically address this issue, we have established a microscopy-based quantitative assay and identified 23 miRNAs that induced contractile phenotypes when over-expressed. These were then correlated to miRNAs identified from RNA-sequencing when comparing cells in the contractile and synthetic states. Using both approaches, six miRNAs (miR-132-3p, miR-138-5p, miR-141-3p, miR-145-5p, miR-150-5p, and miR-22-3p) were filtered as candidates that induce the phenotypic switch from synthetic to contractile. To identify potentially common regulatory mechanisms of these six miRNAs, their predicted targets were compared with five miRNAs sharing ZBTB20, ZNF704, and EIF4EBP2 as common potential targets and four miRNAs sharing 16 common potential targets. The interaction network consisting of these 19 targets and additional 18 hub targets were created to facilitate validation of miRNA-mRNA interactions by suggesting the most plausible pairs. Furthermore, the information on drug candidates was integrated into the network to predict novel combinatorial therapies that encompass the complexity of miRNAs-mediated regulation. This is the first study that combines a phenotypic screening approach with RNA sequencing and bioinformatics to systematically identify miRNA-mediated pathways and to detect potential drug candidates to positively influence the phenotypic switch of VSMCs.

Antioxidant/Pro-Oxidant Actions of Polyphenols From Grapevine and Wine By-Products-Base for Complementary Therapy in Ischemic Heart Diseases

Grape pomace and grape seeds, by-products of the wine industry, and grapevine cane resulting from grapevine pruning are cheap matrices containing important amounts of polyphenols. While there is a continuous need of introducing new ways of these by-products valorization, we propose their use as a source of bioactive polyphenols for complementary therapy in ischemic heart diseases. As oxidative stress plays an important role in these diseases, by their antioxidant/pro-oxidant properties, these compounds, mainly flavan-3-ols, procyanidins, and resveratrol may counteract the damage of the oxidative stress. For instance, to some extent, the grape seed extract, considered as an antioxidant nutritive supplement, may have pro-oxidant activity as well, depending on dose, duration of administration, and other dietary components. In vitro studies confirm that the antioxidant activity of this extract might be mediated by pro-oxidant o-quinones and oxidation products of the polyphenols from grape and winery byproducts, indicating that quinones, as oxidation products, are involved in the modulation of the antioxidant/pro-oxidant balance at the cellular level in the case of catechin-type compounds, in the absence or presence of oxidative stress inducers. In vivo, studies indicate that a grape pomace-rich diet results in a significant increase of the total antioxidant status in the plasma, liver, spleen, and kidneys. Also, the administration of grape pomace shows antioxidant activity with positive effects on health. In this context, the present review aims to present the most recent research focused on the antioxidant/pro-oxidant actions of the bioactive polyphenols from grapevine and wine byproducts, in conditions of ischemic heart diseases as assessed in vitro or in vivo.

Introducing ADNP and SIRT1 as new partners regulating microtubules and histone methylation

Activity-dependent neuroprotective protein (ADNP) is essential for brain formation and function. As such, de novo mutations in ADNP lead to the autistic ADNP syndrome and somatic ADNP mutations may drive Alzheimer's disease (AD) tauopathy. Sirtuin 1 (SIRT1) is positively associated with aging, the major risk for AD. Here, we revealed two key interaction sites for ADNP and SIRT1. One, at the microtubule end-binding protein (EB1 and EB3) Tau level, with EB1/EB3 serving as amplifiers for microtubule dynamics, synapse formation, axonal transport, and protection against tauopathy. Two, on the DNA/chromatin site, with yin yang 1, histone deacetylase 2, and ADNP, sharing a DNA binding motif and regulating SIRT1, ADNP, and EB1 (MAPRE1). This interaction was linked to sex- and age-dependent altered histone modification, associated with ADNP/SIRT1/WD repeat-containing protein 5, which mediates the assembly of histone modification complexes. Single-cell RNA and protein expression analyses as well as gene expression correlations placed SIRT1-ADNP and either MAPRE1 (EB1), MAPRE3 (EB3), or both in the same mouse and human cell; however, while MAPRE1 seemed to be similarly regulated to ADNP and SIRT1, MAPRE3 seemed to deviate. Finally, we demonstrated an extremely tight correlation for the gene transcripts described above, including related gene products. This correlation was specifically abolished in affected postmortem AD and Parkinson's disease brain select areas compared to matched controls, while being maintained in blood samples. Thus, we identified an ADNP-SIRT1 complex that may serve as a new target for the understanding of brain degeneration.

Cardioprotection stimulated by resveratrol and grape products prevents lethal cardiac arrhythmias in an animal model of ischemia and reperfusion

PURPOSE

To evaluate the preventive cardioprotective effects of resveratrol and grape products, such as grape juice and red wine, in animal model of cardiac ischemia and reperfusion.

METHODS

Male Wistar rats orally pretreated for 21-days with resveratrol and grape products were anesthetized and placed on mechanical ventilation to surgically induce cardiac ischemia and reperfusion by obstruction (ischemia) followed by liberation (reperfusion) of blood circulation in left descending coronary artery. These rats were submitted to the electrocardiogram (ECG) analysis to evaluate the effects of pretreatment with resveratrol and grape products on the incidence of ventricular arrhythmias (VA), atrioventricular block (AVB) and lethality (LET) resulting from cardiac ischemia and reperfusion.

RESULTS

It was observed that the incidence of AVB was significantly lower in rats pretreated with resveratrol (25%), grape juice (37.5%) or red wine (12.5%) than in rats treated with saline solution (80%) or ethanol (80%). Similarly, incidence of LET was also significantly lower in rats pretreated with resveratrol (25%), grape juice (25%) or red wine (0%) than in rats treated with saline solution (62.5%) or ethanol (75%).

CONCLUSIONS

These results indicate that the cardioprotective response stimulated by resveratrol and grape products prevents the lethal cardiac arrhythmias in animal model of ischemia and reperfusion, supporting the idea that this treatment can be beneficial for prevention of severe cardiac arrhythmias in patients with ischemic heart disease.

Molecular mechanisms of doxorubicin-induced cardiotoxicity: novel roles of sirtuin 1-mediated signaling pathways

Doxorubicin (DOX) is an anthracycline chemotherapy drug used in the treatment of various types of cancer. However, short-term and long-term cardiotoxicity limits the clinical application of DOX. Currently, dexrazoxane is the only approved treatment by the United States Food and Drug Administration to prevent DOX-induced cardiotoxicity. However, a recent study found that pre-treatment with dexrazoxane could not fully improve myocardial toxicity of DOX. Therefore, further targeted cardioprotective prophylaxis and treatment strategies are an urgent requirement for cancer patients receiving DOX treatment to reduce the occurrence of cardiotoxicity. Accumulating evidence manifested that Sirtuin 1 (SIRT1) could play a crucially protective role in heart diseases. Recently, numerous studies have concentrated on the role of SIRT1 in DOX-induced cardiotoxicity, which might be related to the activity and deacetylation of SIRT1 downstream targets. Therefore, the aim of this review was to summarize the recent advances related to the protective effects, mechanisms, and deficiencies in clinical application of SIRT1 in DOX-induced cardiotoxicity. Also, the pharmaceutical preparations that activate SIRT1 and affect DOX-induced cardiotoxicity have been listed in this review.

DJ-1: A promising therapeutic candidate for ischemia-reperfusion injury

DJ-1 is a multifaceted protein with pleiotropic functions that has been implicated in multiple diseases, ranging from neurodegeneration to cancer and ischemia-reperfusion injury. Ischemia is a complex pathological state arising when tissues and organs do not receive adequate levels of oxygen and nutrients. When the blood flow is restored, significant damage occurs over and above that of ischemia alone and is termed ischemia-reperfusion injury. Despite great efforts in the scientific community to ameliorate this pathology, its complex nature has rendered it challenging to obtain satisfactory treatments that translate to the clinic. In this review, we will describe the recent findings on the participation of the protein DJ-1 in the pathophysiology of ischemia-reperfusion injury, firstly introducing the features and functions of DJ-1 and, successively highlighting the therapeutic potential of the protein.

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DJ-1 has been shown to confer protection in ischemia-reperfusion injury models.

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DJ-1 protection relies on the activation of antioxidant signaling pathways.

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DJ-1 regulates mitochondrial homeostasis during ischemia and reperfusion.

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DJ-1 seems to modulate ion homeostasis during ischemia and reperfusion.

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DJ-1 may represent a promising therapeutic target for ischemia-reperfusion injury.

Purple sweet potato color protects against hepatocyte apoptosis through Sirt1 activation in high-fat-diet-treated mice

Background

Recent evidence indicates that the inhibition of hepatocyte apoptosis is possible to develop a potential therapeutic strategy for nonalcoholic fatty liver disease (NAFLD). Our previous work suggested that purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, effectively improved many features of high-fat diet (HFD)-induced NAFLD. However, whether PSPC ameliorates HFD-induced hepatocyte apoptosis has never been investigated.

Objective

Here we investigated the effects of PSPC on HFD-induced hepatic apoptosis and the mechanisms underlying these effects.

Design

Mice were divided into four groups: Control group, HFD group, HFD + PSPC group and PSPC group. PSPC was administered by daily oral gavage at doses of 700 mg/kg/day for 20 weeks. EX-527 (a SirT1-selective inhibitor) and Sirt1 siRNA were used to demonstrate the Sirt1 dependence of PSPC-mediated effects on apoptotic and survival signaling pathways in vivo and in vitro.

Results

Our results showed that PSPC reduced body weights, hepatic triglyceride contents, histopathological lesions and serum ALT levels in a mouse model of NAFLD induced by HFD. Furthermore, PSPC attenuated HFD-induced hepatocyte apoptosis ratio from 7.27 ± 0.92% to 1.79 ± 0.27% in mouse livers, which is insignificant compared with that of controls. Moreover, PSPC activated Sirt1 by boosting NAD⁺ level in HFD-treated mouse livers. Furthermore, PSPC promoted Sirt1-dependent suppression of P53-mediated apoptotic signaling and activation of Akt survival signaling pathway in HFD-treated mouse livers, which was confirmed by EX527 treatment. Moreover, Sirt1 knockdown abolished these ameliorative effects of PSPC on apoptosis and P53 acetylation and protein expression in PA-treated L02 cells. Ultimately, PSPC reduced Caspase-3 activation and Bax level, and elevated the Bcl-2 level in HFD-treated mouse livers.

Conclusion

PSPC protected against HFD-induced hepatic apoptosis by promoting Sirt1- dependent inhibition of p53-apoptotic pathway and facilitation of Akt survival pathway. This study indicates that PSPC is a candidate for nutritional intervention of NAFLD.

SIRT1-Mediated Protective Effect of Aralia elata (Miq.) Seem against High-Glucose-Induced Senescence in Human Umbilical Vein Endothelial Cells

Aralia elata (Miq.) Seem (AS) is widely been for treating many diseases, enhancing energy, and boosting immunity; however, its protective effects against high-glucose (HG)-triggered endothelial dysfunction and the potential underlying mechanisms have not been investigated. In this study, we determined the effect of AS on senescence in human umbilical vein endothelial cells (HUVECs) and elucidated the mechanisms underlying its anti-aging effects. The senescence model of endothelial cells (ECs) was established by culturing HUVECs in media containing HG (30 mM). We found that the proportion of senescent (senescence-associated β-galactosidase+) cells in the HG group was significantly higher than that in the control group; however, this increase was suppressed by AS treatment. Moreover, cell cycle analysis revealed that AS (20 μg/mL) significantly recovered HG-induced cell cycle arrest in ECs, and Western blot revealed that AS prevented HG-induced decreases in silent information regulator 1 (SIRT1) level and endothelial nitric oxide synthase (eNOS) phosphorylation. These results show that AS delayed HG-induced senescence in ECs by modulation of the SIRT1/5′ AMP-activated protein kinase and AKT/eNOS pathways.

Protective Effects of Dioscin Against Doxorubicin-Induced Hepatotoxicity Via Regulation of Sirt1/FOXO1/NF-κb Signal

Doxorubicin (Dox), an antitumor antibiotic, has therapeutic effects on many kinds of tumors. However, Dox can produce some serious side effects that limit its clinical application. Thus, exploration of effective drug targets or active lead compounds against Dox-induced organ damage is necessary. Dioscin, one natural product, has potent effects against Dox-induced renal injury and cardiotoxicity. However, the effects of dioscin on Dox-induced hepatotoxicity have not been reported. In this study, the results showed that dioscin significantly ameliorated Dox-induced cell injury, reduced reactive oxygen species (ROS) level, and suppressed cell apoptosis in alpha mouse liver 12 (AML-12) cells caused by Dox. In vivo, dioscin evidently decreased the levels of alanine transaminase (ALT), aspartate transaminase (AST), malondialdehyde (MDA); increased the levels of superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px); and alleviated liver injury. Mechanism study showed that dioscin remarkably up-regulated the expression levels of silent information regulator 1 (Sirt1) and heme oxygenase-1 (HO-1) via increase of the nuclear translocation of NF-E2-related factor 2 (Nrf2) and suppressed the expression levels of forkhead box protein O1 (FOXO1) and kelch-like ECH-associated protein-1 (Keap1) to inhibit oxidative stress. Furthermore, dioscin obviously decreased the nuclear translocation of nuclear factor κB (NF-κB) and the mRNA levels of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), and interleukin 6 (IL-6) to suppress inflammation. Meanwhile, dioscin significantly regulated tumor suppressor P53 (P53) expression level and BCL-2-associated X (BAX)/BCL-2 apoptosis regulator (BCL-2) ratio to inhibit cell apoptosis. These results were further validated by knockdown of Sirt1 using siRNA silencing in AML-12 cells, which confirmed that the target of dioscin against Dox-induced hepatotoxicity was Sirt1/FOXO1/NF-κB signal. In short, our findings showed that dioscin exhibited protective effects against Dox-induced liver damage via suppression of oxidative stress, inflammation, and apoptosis, which should be developed as one new candidate for the prevention of Dox-induced liver injury in the future.

DJ-1 overexpression confers the multidrug resistance phenotype to SGC7901 cells by upregulating P-gp and Bcl-2

Gastric cancer (GC) is one of the most malignant tumors with high incidence and mortality worldwide, and the multidrug resistance (MDR) often results in chemotherapy failure in GC. DJ-1 has been well indicated to be associated with drug resistance in multiple cancers. However, the role of DJ-1 in the MDR of gastric cancer cells and its possible mechanism remain to be elucidated. Therefore, the current study was investigated whether DJ-1 expression is differential in parental gastric cancer cell SGC7901 and vincristine (VCR)-induced gastric cancer MDR cell SGC7901/VCR, and whether DJ-1 plays a significant role in development of MDR in gastric cancer. The results showed that DJ-1 expression in SGC7901/VCR cells was significantly higher than its sensitive parental SGC7901 cells. Furthermore, DJ-1 overexpressed gastric cancer cell line SGC7901/LV-DJ-1 led to the increase of cell survival rate, the IC₅₀ of chemotherapeutic drugs and number of cell clones as well as decrease of cell cycle G0/G1 phase ratio compared with its parental cells under the treatment of VCR, adriamycin (ADR), 5-Fluorouracil (5-FU) and cisplatin (DDP). However, the DJ-1 knockdown stable cell line SGC7901/VCR/shDJ-1 reversed the above mentioned series of MDR. Moreover, it was found that upregulation of DJ-1 protein expression promoted the pumping rate of GC cells to ADR and reduced the apoptotic index of GC cells treated with chemotherapeutic drugs by upregulating P-gp and Bcl-2. Similarly, knocking down DJ-1, P-gp or Bcl-2 displayed a converse effect. In conclusion, the current study demonstrated that DJ-1 overexpression confers the MDR phenotype to SGC7901 cells and this process is related to DJ-1 promoting active efflux of drugs and enhancing the anti-apoptotic ability of MDR GC cells by upregulating P-gp and Bcl-2.

Melatonin Inhibits Apoptosis and Oxidative Stress of Mouse Leydig Cells via a SIRT1-Dependent Mechanism

The purpose of the present study is to examine the effects of melatonin on apoptosis and oxidative stress in mouse Leydig cells and to elucidate the mechanisms responsible for these effects. Our results indicated that 10 ng/mL of melatonin significantly promoted cell viability, the ratio of EdU-positive (5-Ethynyl-2'-deoxyuridine) cells, and increased the mRNA expression of proliferating cell nuclear antigen (PCNA), cyclin D1(CCND1), and cell division control protein 42 (CDC42) (p < 0.05). We also observed that melatonin inhibited apoptosis of mouse Leydig cells, accompanied with increased B-cell lymphoma-2 (BCL-2) and decreased BCL2 associated X (BAX) mRNA and protein expression. Moreover, addition of melatonin significantly decreased the reactive oxygen species (ROS) production and malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, while it increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels (p < 0.05). In addition, we also found that melatonin increased the expression of SIRT1 (Silent information regulator 1) (p < 0.05). To explore the role of SIRT1 signaling in melatonin-induced cells, mouse Leydig cells were pretreated with EX527, an inhibitor of SIRT1. The protective effects of melatonin on mouse Leydig cells were reversed by EX527, as shown by decreased cell proliferation and increased cell apoptosis and oxidative stress. In summary, our results demonstrated that melatonin inhibited apoptosis and oxidative stress of mouse Leydig cells through a SIRT1-dependent mechanism.