Resveratrol rescues cadmium-induced mitochondrial injury by enhancing transcriptional regulation of PGC-1α and SOD2 via the Sirt3/FoxO3a pathway in TCMK-1 cells

Sirtuin 3 in renal diseases and aging: From mechanisms to potential therapies

The longevity protein sirtuins (SIRTs) belong to a family of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases. In mammals, SIRTs comprise seven members (SIRT1-7) which are localized to different subcellular compartments. As the most prominent mitochondrial deacetylases, SIRT3 is known to be regulated by various mechanisms and participate in virtually all aspects of mitochondrial homeostasis and metabolism, exerting significant impact on multiple organs. Notably, the kidneys possess an abundance of mitochondria that provide substantial energy for filtration and reabsorption. A growing body of evidence now supports the involvement of SIRT3 in several renal diseases, including acute kidney injury, chronic kidney disease, and diabetic nephropathy; notably, these diseases are all associated with aging. In this review, we summarize the emerging role of SIRT3 in renal diseases and aging, and highlights the intricate mechanisms by which SIRT3 exerts its effects. In addition, we highlight the potential therapeutic significance of modulating SIRT3 and provide valuable insights into the therapeutic role of SIRT3 in renal diseases to facilitate clinical application.

Mechanisms of Phytoremediation by Resveratrol against Cadmium Toxicity

Cadmium (Cd) toxicity poses a significant threat to human health and the environment due to its widespread occurrence and persistence. In recent years, considerable attention has been directed towards exploring natural compounds with potential protective effects against Cd-induced toxicity. Among these compounds, resveratrol (RV) has emerged as a promising candidate, demonstrating a range of beneficial effects attributed to its antioxidant and anti-inflammatory properties. This literature review systematically evaluates the protective role of RV against Cd toxicity, considering the various mechanisms of action involved. A comprehensive analysis of both in vitro and in vivo studies is conducted to provide a comprehensive understanding of RV efficacy in mitigating Cd-induced damage. Additionally, this review highlights the importance of phytoremediation strategies in addressing Cd contamination, emphasizing the potential of RV in enhancing the efficiency of such remediation techniques. Through the integration of diverse research findings, this review underscores the therapeutic potential of RV in combating Cd toxicity and underscores the need for further investigation to elucidate its precise mechanisms of action and optimize its application in environmental and clinical settings.

Sulforaphane Exposure Prevents Cadmium-Induced Toxicity and Mitochondrial Dysfunction in the Nematode Caenorhabditis elegans by Regulating the Insulin/Insulin-like Growth Factor Signaling (IIS) Pathway

Cadmium (Cd) is a heavy metal that is highly toxic to humans and animals. Its adverse effects have been widely associated with mitochondrial alterations. However, there are not many treatments that target mitochondria. This study aimed to evaluate the impact of sulforaphane (SFN) pre-exposure against cadmium chloride (CdCl2)-induced toxicity and mitochondrial alterations in the nematode Caenorhabditis elegans (C. elegans), by exploring the role of the insulin/insulin-like growth factor signaling pathway (IIS). The results revealed that prior exposure to SFN protected against CdCl2-induced mortality and increased lifespan, body length, and mobility while reducing lipofuscin levels. Furthermore, SFN prevented mitochondrial alterations by increasing mitochondrial membrane potential (Δψm) and restoring mitochondrial oxygen consumption rate, thereby decreasing mitochondrial reactive oxygen species (ROS) production. The improvement in mitochondrial function was associated with increased mitochondrial mass and the involvement of the daf-16 and skn-1c genes of the IIS signaling pathway. In conclusion, exposure to SFN before exposure to CdCl2 mitigates toxic effects and mitochondrial alterations, possibly by increasing mitochondrial mass, which may be related to the regulation of the IIS pathway. These discoveries open new possibilities for developing therapies to reduce the damage caused by Cd toxicity and oxidative stress in biological systems, highlighting antioxidants with mitochondrial action as promising tools.

Nickel induces mitochondrial damage in renal cells in vitro and in vivo through its effects on mitochondrial biogenesis, fusion, and fission

Nickel (Ni) and its compounds are common, widely distributed components of hazardous waste in the chemical industry. Excessive exposure to Ni can cause kidney damage in humans and animals. We investigated the impact of Ni on renal mitochondria using in vivo and in vitro models of Ni nephrotoxicity, and explored the Ni nephrotoxic mechanism. We showed that nickel chloride (NiCl2) damaged the renal mitochondria, causing mitochondrial swelling, breakage of the mitochondrial cristae, increased levels of mitochondrial reactive oxygen species (mt-ROS), and depolarization of the mitochondrial membrane potential (MMP). The levels of the mitochondrial respiratory chain complexes I-IV were reduced in the kidneys of mice treated with NiCl2. In addition, NiCl2 treatment inhibited mitochondrial biogenesis in renal cells by down-regulating mRNA and the protein expression of TFAM, PGC-1α, and NRF1. Moreover, NiCl2 reduced the levels of the proteins involved in mitochondrial fusion, including Mfn1 and Mfn2, while significantly augmenting the levels of the proteins Fis1 and Drip1 involved in mitochondrial fission in renal cells. Taken together, these results suggested that NiCl2 inhibited mitochondrial biogenesis, suppressed mitochondrial fusion, and promoted mitochondrial fission, resulting in mitochondrial dysfunction in renal cells, ultimately causing renal injury. This study provided novel insights into the mechanisms of nephrotoxicity of Ni and new ideas for the development of targeted treatments for Ni-induced kidney injury.

Changes of LncRNAs during the Process of Antioxidants Antagonize Cadmium-Induced Oxidative Damage in Islet β Cells

Long non-coding RNAs (LncRNAs) play important regulatory roles in oxidative damage. Resveratrol, curcumin, and cyanidin are phytogenic antioxidants widely existing in nature and they have been proved to antagonize certain heavy metal-induced oxidative damage in cells. However, can they antagonize oxidative damage induced by cadmium in islet β cells? Are their mechanisms of antagonizing oxidative damage related to LncRNAs? In this study, we first detected the cell viability of each group by CCK8 assay. Next, reactive oxygen species (ROS) were detected by the fluorescent probe. The contents of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) were detected according to the instructions of corresponding kits. At last, the levels of LncRNAs were detected by fluorescence quantitative real-time polymerase chain reaction (qPCR). The results showed that resveratrol, curcumin and cyanidin were able to reverse the reduction of cell viability induced by cadmium (CdSO4). Further determination revealed that SOD activities of the resveratrol+CdSO4, curcumin+CdSO4, and cyanidin+CdSO4 treatment groups increased significantly, and ROS levels and MDA contents dramatically decreased when compared with single CdSO4-treated group. More importantly, the levels of three CdSO4-elevated LncRNAs (NONMMUT029382, ENSMUST00000162103, ENSMUST00000117235) were all decreased and levels of three CdSO4-inhibited LncRNAs (NONMMUT036805, NONMMUT014565, NONMMUT065427) were increased after the pretreatment of resveratrol, curcumin and cyanidin. In summary, resveratrol, curcumin and cyanidin may effectly reverse the cadmium-induced oxidative damage and suggest that phytogenic antioxidants may prevent cells from cadmium-induced oxidative damage through changing the levels of LncRNAs.

Heavy Metal Exposure: Molecular Pathways, Clinical Implications, and Protective Strategies

Heavy metals are often found in soil and can contaminate drinking water, posing a serious threat to human health. Molecular pathways and curation therapies for mitigating heavy metal toxicity have been studied for a long time. Recent studies on oxidative stress and aging have shown that the molecular foundation of cellular damage caused by heavy metals, namely, apoptosis, endoplasmic reticulum stress, and mitochondrial stress, share the same pathways as those involved in cellular senescence and aging. In recent aging studies, many types of heavy metal exposures have been used in both cellular and animal aging models. Chelation therapy is a traditional treatment for heavy metal toxicity. However, recently, various antioxidants have been found to be effective in treating heavy metal-induced damage, shifting the research focus to investigating the interplay between antioxidants and heavy metals. In this review, we introduce the molecular basis of heavy metal-induced cellular damage and its relationship with aging, summarize its clinical implications, and discuss antioxidants and other agents with protective effects against heavy metal damage.

NLRP3 inflammasome-mediated pyroptosis involvement in cadmium exposure-induced cognitive deficits via the Sirt3-mtROS axis

Cadmium (Cd), a toxic heavy metal, exerts deleterious effects on neuronal survival and cognitive function. NOD-like receptor 3 (NLRP3) inflammasome-dependent pyroptosis has been linked to Cd-induced cytotoxicity. The current research intended to elucidate the role of NLRP3 inflammasome-mediated pyroptosis in Cd-evoked neuronal death and cognitive impairments and the underlying mechanisms. Exposure to 1 mg/kg Cd for 8 weeks led to hippocampal-dependent cognitive deficits and neural/synaptic damage in mice. NLRP3 inflammasome-related protein expression (NLRP3, ASC, and caspase1 p20) and neuronal pyroptosis were significantly upregulated in Cd-treated hippocampi and SH-SY5Y cells. Moreover, pretreatment with the NLRP3 inhibitor MCC950 mitigated Cd-elicited NLRP3 inflammasome activation and subsequent neuronal pyroptosis in SH-SY5Y cells. Furthermore, exposure to Cd downregulated Sirt3 expression, suppressed SOD2 activity by hyperacetylation, and enhanced mtROS accumulation in vivo and in vitro. Notably, Cd-induced NLRP3 inflammasome-dependent neuronal pyroptosis was attenuated by a mtROS scavenger or Sirt3 overexpression in SH-SY5Y cells. In addition, Cd failed to further suppress SOD activity and activate NLRP3 inflammasome-dependent neuronal pyroptosis in Sirt3 shRNA-treated SH-SY5Y cells. Collectively, our findings indicate that Cd exposure induces neuronal injury and cognitive deficits by activating NLRP3 inflammasome-dependent neuronal pyroptosis and that activation of the NLRP3 inflammasome is partially mediated by the Sirt3-mtROS axis.

Resveratrol reduces ROS-induced ferroptosis by activating SIRT3 and compensating the GSH/GPX4 pathway

BACKGROUND

Intestinal ischemia-reperfusion injury occurs in acute intestinal obstruction, intussusception, acute mesenteric artery embolism, and other diseases and can lead to local intestinal necrosis, distant organ involvement, or systemic reactions, with high morbidity and mortality. Ferroptosis plays a crucial role in intestinal ischemia-reperfusion injury, and inhibition of ferroptosis may provide new approaches for treating the disease. SIRT3 protects cells from oxidative stress and may be involved in the process of ferroptosis. We hypothesized that resveratrol, an agonist of SIRT3, could ameliorate intestinal ischemia-reperfusion injury by compensating the GSH/GPX4 pathway.

METHODS

Intestinal ischemia-reperfusion (I/R) and Caco-2 hypoxia-reoxygenation models were established. Transmission electron microscopy was used to assess mitochondrial function; the Chiu's score was used to evaluate the degree of intestinal mucosal injury based on HE staining; and Western blot was used to detect the SIRT3/FoxO3a pathway, tight junction proteins and ferroptosis-related protein expression. Sirt3-/- C57, shSIRT3-Caco-2 cells and siFoxO3a-Caco-2 cells were established. C11-BODIPY was used to detect lipid peroxide in cells; FD4 and IFABP were used to detect intestinal permeability; MitoSOX was used to detect ROS levels; and MitoTracker and immunofluorescence colocalization were used to detect SIRT3 levels.

RESULTS

In the intestinal I/R model, I/R injury occurs mainly during the reperfusion period and leads to ferroptosis through the GSH/GPX4 pathway. Resveratrol could reduce ferroptosis and ameliorate I/R injury by activating SIRT3. In Sirt3-/- mice, more intestinal mucosal cells underwent ferroptosis, I/R injury was more severe, and resveratrol lost the ability to ameliorate I/R injury. In addition, hypoxia-reoxygenation increased RSL3-induced ferroptosis sensitivity in Caco-2 cells in vitro. In the presence of shSIRT3 or RSL3 alone, resveratrol could ameliorate Caco-2 ferroptosis, but not RSL3-induced shSIRT3-Caco-2 ferroptosis. Furthermore, resveratrol might activate the SIRT3/FoxO3a pathway, increase the expression of SOD2 and catalase, and inhibit ROS generation, thus reducing lipid peroxidation and ferroptosis.

CONCLUSION

To date, this is the first study to show that resveratrol ameliorates intestinal ischemia-reperfusion injury by activating SIRT3 and reducing ferroptosis. Resveratrol can reduce intestinal ischemia-reperfusion injury by activating the SIRT3/FoxO3a pathway, increasing the expression of SOD2 and catalase, reducing ROS and LPO production, compensating for the GSH/GPX4 pathway and inhibiting ferroptosis. Resveratrol increases the expression of SOD2 and catalase, reduces the production of ROS and LPO, compensates for the GSH/GPX4 pathway and inhibits ferroptosis by activating the SIRT3/FoxO3a pathway.

Apoptotic vesicles resist oxidative damage in noise-induced hearing loss through activation of FOXO3a-SOD2 pathway

BACKGROUND

Mesenchymal stem cell (MSC) transplantation is a promising therapeutic approach for noise-induced hearing loss (NIHL). As the indispensable role of apoptosis in MSC transplantation was raised, the benefits of MSC-derived apoptotic vesicles (apoVs) in several disease models have been proved. However, whether apoVs benefit in NIHL have not been studied yet.

METHODS

Female CBA/J mice and HEI-OC1 cells were used in this study. Flow cytometry, nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) were used to characterize apoVs. Proteomic analysis was used to identify function proteins in apoVs. Immunofluorescence was used to reveal distribution pattern. Auditory brainstem response (ABR) test was used to measure the effect of apoVs treatment. DCFH-DA staining and MitoSOX staining were used to indicate oxidative damage. Western-blot and qRT-PCR were used to study the signaling pathways.

RESULTS

We found that apoVs can be endocytosed by hair cells through systemic administration. Importantly, apoVs administration effectively attenuated NIHL and reduced hair cell loss by resisting oxidative damage in vivo. Further, apoVs application activated forkhead box o3 (FOXO3a)-mitochondrial superoxide dismutase 2(SOD2) pathway, which may relate to signal transduction and activators of transcription 3 (STAT3) in apoVs.

CONCLUSIONS

These findings uncovered the role of apoVs in preventing NIHL and resisting oxidative damage, indicating that apoVs is a promising way for inner ear delivery and a prospective cell-free therapy for NIHL.

Natural products for kidney disease treatment: Focus on targeting mitochondrial dysfunction

The patients with kidney diseases are increasing rapidly all over the world. With the rich abundance of mitochondria, kidney is an organ with a high consumption of energy. Hence, renal failure is highly correlated with the breakup of mitochondrial homeostasis. However, the potential drugs targeting mitochondrial dysfunction are still in mystery. The natural products have the superiorities to explore the potential drugs regulating energy metabolism. However, their roles in targeting mitochondrial dysfunction in kidney diseases have not been extensively reviewed. Herein, we reviewed a series of natural products targeting mitochondrial oxidative stress, mitochondrial biogenesis, mitophagy, and mitochondrial dynamics. We found lots of them with great medicinal values in kidney disease. Our review provides a wide prospect for seeking the effective drugs targeting kidney diseases.

Notoginseng leaf triterpenes ameliorates mitochondrial oxidative injury via the NAMPT-SIRT1/2/3 signaling pathways in cerebral ischemic model rats

BACKGROUND

Due to the interrupted blood supply in cerebral ischemic stroke (CIS), ischemic and hypoxia results in neuronal depolarization, insufficient NAD+, excessive levels of ROS, mitochondrial damages, and energy metabolism disorders, which triggers the ischemic cascades. Currently, improvement of mitochondrial functions and energy metabolism is as a vital therapeutic target and clinical strategy. Hence, it is greatly crucial to look for neuroprotective natural agents with mitochondria protection actions and explore the mediated targets for treating CIS. In the previous study, notoginseng leaf triterpenes (PNGL) from Panax notoginseng stems and leaves was demonstrated to have neuroprotective effects against cerebral ischemia/reperfusion injury. However, the potential mechanisms have been not completely elaborate. Methods: The model of middle cerebral artery occlusion and reperfusion (MCAO/R) was adopted to verify the neuroprotective effects and potential pharmacology mechanisms of PNGL in vivo. Antioxidant markers were evaluated by kit detection. Mitochondrial function was evaluated by ATP content measurement, ATPase, NAD and NADH kits. And the transmission electron microscopy (TEM) and pathological staining (H&E and Nissl) were used to detect cerebral morphological changes and mitochondrial structural damages. Western blotting, ELISA and immunofluorescence assay were utilized to explore the mitochondrial protection effects and its related mechanisms in vivo. Results: In vivo, treatment with PNGL markedly reduced excessive oxidative stress, inhibited mitochondrial injury, alleviated energy metabolism dysfunction, decreased neuronal loss and apoptosis, and thus notedly raised neuronal survival under ischemia and hypoxia. Meanwhile, PNGL significantly increased the expression of nicotinamide phosphoribosyltransferase (NAMPT) in the ischemic regions, and regulated its related downstream SIRT1/2/3-MnSOD/PGC-1α pathways. Conclusion: The study finds that the mitochondrial protective effects of PNGL are associated with the NAMPT-SIRT1/2/3-MnSOD/PGC-1α signal pathways. PNGL, as a novel candidate drug, has great application prospects for preventing and treating ischemic stroke.

Resveratrol-Mediated Regulation of Mitochondria Biogenesis-associated Pathways in Neurodegenerative Diseases: Molecular Insights and Potential Therapeutic Applications

Neurodegenerative disorders include different neurological conditions that affect nerve cells, causing the progressive loss of their functions and ultimately leading to loss of mobility, coordination, and mental functioning. The molecular mechanisms underpinning neurodegenerative disease pathogenesis are still unclear. Nonetheless, there is experimental evidence to demonstrate that the perturbation of mitochondrial function and dynamics play an essential role. In this context, mitochondrial biogenesis, the growth, and division of preexisting mitochondria, by controlling mitochondria number, plays a vital role in maintaining proper mitochondrial mass and function, thus ensuring efficient synaptic activity and brain function. Mitochondrial biogenesis is tightly associated with the control of cell division and variations in energy demand in response to extracellular stimuli; therefore, it may represent a promising therapeutic target for developing new curative approaches to prevent or counteract neurodegenerative disorders. Accordingly, several inducers of mitochondrial biogenesis have been proposed as pharmacological targets for treating diverse central nervous system conditions. The naturally occurring polyphenol resveratrol has been shown to promote mitochondrial biogenesis in various tissues, including the nervous tissue, and an ever-growing number of studies highlight its neurotherapeutic potential. Besides preventing cognitive impairment and neurodegeneration through its antioxidant and anti-inflammatory properties, resveratrol has been shown to be able to enhance mitochondria biogenesis by acting on its main effectors, including PGC-1α, SIRT1, AMPK, ERRs, TERT, TFAM, NRF-1 and NRF-2. This review aims to present and discuss the current findings concerning the impact of resveratrol on the machinery and main effectors modulating mitochondrial biogenesis in the context of neurodegenerative diseases.

Protective effects of Gypenoside XVII against cerebral ischemia/reperfusion injury via SIRT1-FOXO3A- and Hif1a-BNIP3-mediated mitochondrial autophagy

BACKGROUND

Mitochondrial autophagy maintains mitochondrial function and cellular homeostasis and plays a critical role in the pathological process of cerebral ischemia/reperfusion injury (CIRI). Whether Gypenoside XVII (GP17) has regulatory effects on mitochondrial autophagy against CIRI remains unclear. The purpose of this study was to investigate the pharmacodynamic effects and mechanisms of GP17 on mitochondrial autophagy after CIRI.

METHODS

A rat middle cerebral artery occlusion/reperfusion (MCAO/R) model was used to assess the effects of GP17 against CIRI and to explore the underlying mechanisms. An oxygen-glucose deprivation/reoxygenation (OGD/R) cell model was used to verify the ameliorative effects on mitochondrial damage and to probe the autophagy pathways involved in combating neural injuries.

RESULTS

The in vivo results showed that GP17 significantly improved mitochondrial metabolic functions and suppressed cerebral ischemic injury, possibly via the autophagy pathway. Further research revealed that GP17 maintains moderate activation of autophagy under ischemic and OGD conditions, producing neuroprotective effects against CIRI, and that the regulation of mitochondrial autophagy is associated with crosstalk between the SIRT1-FOXO3A and Hif1a-BNIP3 signalling pathway that is partially eliminated by the specific inhibitors AGK-7 and 2-ME.

CONCLUSION

Overall, this work offers new insights into the mechanisms by which GP17 protects against CIRI and highlights the potential of therapy with Notoginseng leaf triterpene compounds as a novel clinical strategy in humans.

Role of FOXO3a Transcription Factor in the Regulation of Liver Oxidative Injury

Oxidative stress has been identified as a key mechanism in liver damage caused by various chemicals. The transcription factor FOXO3a has emerged as a critical regulator of redox imbalance. Multiple post-translational changes and epigenetic processes closely regulate the activity of FOXO3a, resulting in synergistic or competing impacts on its subcellular localization, stability, protein-protein interactions, DNA binding affinity, and transcriptional programs. Depending on the chemical nature and subcellular context, the oxidative-stress-mediated activation of FOXO3a can induce multiple transcriptional programs that play crucial roles in oxidative injury to the liver by chemicals. Here, we mainly review the role of FOXO3a in coordinating programs of genes that are essential for cellular homeostasis, with an emphasis on exploring the regulatory mechanisms and potential application of FOXO3a as a therapeutic target to prevent and treat liver oxidative injury.

Mitochondrial unfolded protein response in ischemia-reperfusion injury

Mitochondrial unfolded protein response (UPRmt) is a mitochondrial stress response that activates the transcriptional program of mitochondrial chaperone proteins and proteases to keep protein homeostasis in mitochondria. Ischemia-reperfusion injury results in multiple severe clinical issues linked to high morbidity and mortality in various disorders. The pathophysiology and pathogenesis of ischemia-reperfusion injury are complex and multifactorial. Emerging evidence showed the roles of UPRmt signaling in ischemia-reperfusion injury. Herein, we discuss the regulatory mechanisms underlying UPRmt signaling in C. elegans and mammals. Furthermore, we review the recent studies into the roles and mechanisms of UPRmt signaling in ischemia-reperfusion injury of the heart, brain, kidney, and liver. Further research of UPRmt signaling will potentially develop novel therapeutic strategies against ischemia-reperfusion injury.

The Effect of Polyphenols on Kidney Disease: Targeting Mitochondria

Mitochondrial function, including oxidative phosphorylation (OXPHOS), mitochondrial biogenesis, and mitochondria dynamics, are essential for the maintenance of renal health. Through modulation of mitochondrial function, the kidneys are able to sustain or recover acute kidney injury (AKI), chronic kidney disease (CKD), nephrotoxicity, nephropathy, and ischemia perfusion. Therapeutic improvement in mitochondrial function in the kidneys is related to the regulation of adenosine triphosphate (ATP) production, free radicals scavenging, decline in apoptosis, and inflammation. Dietary antioxidants, notably polyphenols present in fruits, vegetables, and plants, have attracted attention as effective dietary and pharmacological interventions. Considerable evidence shows that polyphenols protect against mitochondrial damage in different experimental models of kidney disease. Mechanistically, polyphenols regulate the mitochondrial redox status, apoptosis, and multiple intercellular signaling pathways. Therefore, this review attempts to focus on the role of polyphenols in the prevention or treatment of kidney disease and explore the molecular mechanisms associated with their pharmacological activity.

Apigenin Attenuates Mesoporous Silica Nanoparticles-Induced Nephrotoxicity by Activating FOXO3a

Mesoporous silica nanoparticles (MSNs) are widely used in many biomedical applications and clinical fields. However, the applications of MSNs are limited by their severe toxicity. Apigenin (AG) has demonstrated pharmacological effects with low toxicity. The aim of this study was to clarify the role of AG in the progression of MSNs-induced renal injury. BALB/c mice and NRK-52E cells were exposed to MSNs with or without AG. AG protected mice and NRK-52E cells from the MSNs-induced pathological variations in renal tissues and decreased cell viability. AG significantly reduced the levels of serum blood urea nitrogen (BUN) and serum creatinine (Scr), upregulated the levels of superoxide dismutase (SOD), glutathione (GSH) and catalase (CAT), and improved the pathological changes of the kidney in MSNs-treated mice. The protective effects of AG were associated with its ability to increase the levels of antioxidants, reduce the accumulation of ROS, and inhibit the expression of the inflammatory mediators (TNF-α, IL-6). In addition, AG treatment upregulated the activity of FOXO3a, increased the level of IkBα, and reduced the nuclear translocation of NF-κB, which ultimately alleviated MSNs-induced inflammation. Nuclear FOXO3a translocation also triggered antioxidant gene transcription and protected nephrocyte from oxidative damage. However, knockdown of FOXO3a significantly blocked the protective effects of AG. These findings suggested that AG could be a promising therapeutic strategy for MSNs-induced nephrotoxicity, and this protective effect might be related to the suppression of oxidative stress and inflammation via the FOXO3a/NF-κB pathway.

TRAF2/ASK1/JNK Signaling Pathway Is Involved in the Lung Apoptosis of Swine Induced by Cadmium Exposure

Cadmium (Cd), a toxic heavy metal, exists widely in the environment, which can enter organisms through a variety of ways and cause damage to various organs and tissues. However, the mechanism of lung toxicity in swine after Cd exposure is still unclear. To explore the molecular mechanism of swine lung damage caused by Cd exposure, we established the model of Cd exposure, and Cd chloride (20 mg/kg CdCl₂) was added to the diet of swine for continuous exposure for 40 days. TUNEL staining showed that the apoptosis of swine lung increased significantly after Cd exposure. Meanwhile, the results of qRT-PCR showed that Cd induced oxidative stress and inhibited the expression of antioxidant enzymes including CAT, GCLM, GST, SOD, and GSH-px in lung tissue. Cd exposure activated mitochondrial apoptosis pathway via the TRAF2/ASK1/JNK signaling pathway. In brief, we considered that Cd exposure causes oxidative stress in lung and induces lung cell apoptosis through the TRAF2/ASK1/JNK pathway and increases the expression of HSPs to resist the toxicity of Cd. Our research enriches the theoretical basis of Cd toxicity and provides reference for comparative medicine.

Insight into the mitochondrial unfolded protein response and cancer: opportunities and challenges

The mitochondrial unfolded protein response (UPR^mt) is an evolutionarily conserved protective transcriptional response that maintains mitochondrial proteostasis by inducing the expression of mitochondrial chaperones and proteases in response to various stresses. The UPR^mt-mediated transcriptional program requires the participation of various upstream signaling pathways and molecules. The factors regulating the UPR^mt in Caenorhabditis elegans (C. elegans) and mammals are both similar and different. Cancer cells, as malignant cells with uncontrolled proliferation, are exposed to various challenges from endogenous and exogenous stresses. Therefore, in cancer cells, the UPR^mt is hijacked and exploited for the repair of mitochondria and the promotion of tumor growth, invasion and metastasis. In this review, we systematically introduce the inducers of UPR^mt, the biological processes in which UPR^mt participates, the mechanisms regulating the UPR^mt in C. elegans and mammals, cross-tissue signal transduction of the UPR^mt and the roles of the UPR^mt in promoting cancer initiation and progression. Disrupting proteostasis in cancer cells by targeting UPR^mt constitutes a novel anticancer therapeutic strategy.

Tenovin-1 inhibited dengue virus replication through SIRT2

Dengue fever is a common arbovirus disease, which has been spread to the entire tropical world. At present, effective drugs for the treatment of dengue fever have not yet appeared, and the dengue vaccines studied in various countries have also experienced severe adverse reactions. Thus it is urgent to find new chemicals against dengue virus. Now we found Sirtuins (SIRTs) were increased during dengue virus infection and tenovin-1, a SIRT1/2 inhibitor, showed an impressive antiviral ability in vitro. In BHK-21 cells, tenovin-1 inhibited the replication of DENV2 with an EC50 at 3.41 ± 1.10 μM, also inhibited other three types of dengue viruses with EC50 at 0.97 ± 1.11 μM, 1.81 ± 1.08 μM, 3.81 ± 1.34 μM respectively. Moreover, the cytopathic effect-induced DENV2 was largely improved by tenovin-1 treatment and the release of progeny viruses was inhibited by tenovin-1 treatment. At the same time, the viral protein level and mRNA level were decreased with tenovin-1 treatment after dengue virus infection. From the drug-addition assay, the tenovin-1 played its antiviral after viral infection, which indicated tenovin-1 was not a microbicide. Apart from its antiviral effect, tenovin-1 inhibited the inflammatory response caused by DENV2, reducing the release of inflammatory factors during viral infection. The antiviral effect of tenovin-1 was abrogated with SIRT agonist or SIRT2 knockdown treatment, which indicated the effect of tenovin-1 was on-target. In conclusion, tenovin-1 was proved to be a promising compound against flavivirus infection through SIRT2, which should be pay more attention for further study.

Metabolomic Alterations in the Digestive System of the Mantis Shrimp Oratosquilla oratoria Following Short-Term Exposure to Cadmium

Mantis shrimp Oratosquilla oratoria is an economically critical aquatic species along the coast of China but strongly accumulates marine pollutant cadmium (Cd) in its digestive system. It is necessary to characterize the toxicity of Cd in the digestive system of mantis shrimp. The metabolic process is an essential target of Cd toxicity response. In this work, we used ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-TOF-MS) for untargeted metabolomics to characterize the metabolic changes in the digestive system of O. oratoria, exposed to 0.05 mg/L for 96 h. The aim of this study was to further investigate the effect of O. oratoria on Cd response to toxicity and develop biomarkers. Metabolomics analysis showed the alteration of metabolism in the digestive system of mantis shrimp under Cd stress. A total of 91 metabolites were differentially expressed and their main functions were classified into amino acids, phospholipids, and fatty acid esters. The enrichment results of differential metabolite functional pathways showed that biological processes such as amino acid metabolism, transmembrane transport, energy metabolism, and signal transduction are significantly affected. Based on the above results, the Cd-induced oxidative stress and energy metabolism disorders were characterized by the differential expression of amino acids and ADP in mantis shrimp, while the interference of transmembrane transport and signal transduction was due to the differential expression of phospholipids. Overall, this work initially discussed the toxicological response of Cd stress to O. oratoria from the metabolic level and provided new insights into the mechanism.

Prospective Pharmacological Potential of Resveratrol in Delaying Kidney Aging

Aging is an unavoidable part of life. The more aged we become, the more susceptible we become to various complications and damages to the vital organs, including the kidneys. The existing drugs for kidney diseases are mostly of synthetic origins; thus, natural compounds with minimal side-effects have attracted growing interest from the scientific community and pharmaceutical companies. A literature search was carried out to collect published research information on the effects of resveratrol on kidney aging. Recently, resveratrol has emerged as a potential anti-aging agent. This versatile polyphenol exerts its anti-aging effects by intervening in various pathologies and multi-signaling systems, including sirtuin type 1, AMP-activated protein kinase, and nuclear factor-κB. Researchers are trying to figure out the detailed mechanisms and possible resveratrol-mediated interventions in divergent pathways at the molecular level. This review highlights (i) the causative factors implicated in kidney aging and the therapeutic aspects of resveratrol, and (ii) the effectiveness of resveratrol in delaying the aging process of the kidney while minimizing all possible side effects.

Discovering the Protective Effects of Resveratrol on Aflatoxin B1-Induced Toxicity: A Whole Transcriptomic Study in a Bovine Hepatocyte Cell Line

Aflatoxin B1 (AFB1) is a natural feed and food contaminant classified as a group I carcinogen for humans. In the dairy industry, AFB1 and its derivative, AFM1, are of concern for the related economic losses and their possible presence in milk and dairy food products. Among its toxic effects, AFB1 can cause oxidative stress. Thus, dietary supplementation with natural antioxidants has been considered among the strategies to mitigate AFB1 presence and its toxicity. Here, the protective role of resveratrol (R) has been investigated in a foetal bovine hepatocyte cell line (BFH12) exposed to AFB1, by measuring cytotoxicity, transcriptional changes (RNA sequencing), and targeted post-transcriptional modifications (lipid peroxidation, NQO1 and CYP3A enzymatic activity). Resveratrol reversed the AFB1-dependent cytotoxicity. As for gene expression, when administered alone, R induced neglectable changes in BFH12 cells. Conversely, when comparing AFB1-exposed cells with those co-incubated with R+AFB1, greater transcriptional variations were observed (i.e., 840 DEGs). Functional analyses revealed that several significant genes were involved in lipid biosynthesis, response to external stimulus, drug metabolism, and inflammatory response. As for NQO1 and CYP3A activities and lipid peroxidation, R significantly reverted variations induced by AFB1, mostly corroborating and/or completing transcriptional data. Outcomes of the present study provide new knowledge about key molecular mechanisms involved in R antioxidant-mediated protection against AFB1 toxicity.

MCU-Dependent mROS Generation Regulates Cell Metabolism and Cell Death Modulated by the AMPK/PGC-1α/SIRT3 Signaling Pathway

The mitochondrial calcium uniporter is an intensively investigated calcium channel, and its molecular components, structural features, and encoded genes have long been explored. Further studies have shown that the mitochondrial calcium unidirectional transporter (MCU) is a macromolecular complex related to intracellular and extracellular calcium regulation. Based on the current understanding, the MCU is crucial for maintaining cytosolic Ca²⁺ (cCa²⁺) homeostasis by modulating mitochondrial Ca²⁺ (mCa²⁺) uptake. The elevation of MCU-induced calcium levels is confirmed to be the main cause of mitochondrial reactive oxygen species (mROS) generation, which leads to disordered cellular metabolic patterns and cell death. In particular, in an I/R injury model, cancer cells, and adipocytes, MCU expression is maintained at high levels. As is well accepted, the AMPK/PGC-1α/SIRT3 pathway is believed to have an affinity for mROS formation and energy consumption. Therefore, we identified a link between MCU-related mROS formation and the AMPK/PGC-1α/SIRT3 signaling pathway in controlling cell metabolism and cell death, which may provide a new possibility of targeting the MCU to reverse relevant diseases.

Sirtuins as molecular targets, mediators, and protective agents in metal-induced toxicity

Metal dyshomeostasis, and especially overexposure, is known to cause adverse health effects due to modulation of a variety of metabolic pathways. An increasing body of literature has demonstrated that metal exposure may affect SIRT signaling, although the existing data are insufficient. Therefore, in this review we discuss the available data (PubMed-Medline, Google Scholar) on the influence of metal overload on sirtuin (SIRT) signaling and its association with other mechanisms involved in metal-induced toxicity. The existing data demonstrate that cadmium (Cd), mercury (Hg), arsenic (As), lead (Pb), aluminium (Al), hexavalent chromium (Cr^VI), manganese (Mn), iron (Fe), and copper (Cu) can inhibit SIRT1 activity. In addition, an inhibitory effect of Cd, Pb, As, and Fe on SIRT3 has been demonstrated. In turn, metal-induced inhibition of SIRT was shown to affect deacetylation of target proteins including FOXO, PGC1α, p53 and NF-kB. Increased acetylation downregulates PGC1α signaling pathway, resulting in cellular altered redox status and increased susceptibility to oxidative stress, as well as decreased mitochondrial biogenesis. Lower rates of LKB1 deacetylation may be responsible for metal-induced decreases in AMPK activity and subsequent metabolic disturbances. A shift to the acetylated FOXO results in increased expression of pro-apoptotic genes which upregulates apoptosis together with increased p53 signaling. Correspondingly, decreased NF-kB deacetylation results in upregulation of target genes of proinflammatory cytokines, enzymes, and cellular adhesion molecules thus promoting inflammation. Therefore, alterations in sirtuin activity may at least partially mediate metal-induced metabolic disturbances that have been implicated in neurotoxicity, nephrotoxicity, cardiotoxicity, and other toxic effects of heavy metals.

[The role of resveratrol on heavy metal-induced oxidative stress]

Introduction

Introduction and objetives: oxidative stress is considered one of the main mechanisms of genotoxicity and carcinogenicity of heavy metals. In contrast, resveratrol has antioxidant properties and is one of the most studied polyphenols due to its wide variety of beneficial health effects. However, there are no systematic reviews of the scientific literature in which the effects of resveratrol on oxidative stress induced by heavy metals are analyzed. Methods: in this review, articles were searched using the PubMed and ScienceDirect databases (1996-2018). After applying various filters, eleven in vivo and in vitro researches were considered, in which the effects of resveratrol on oxidative stress induced by arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr) and iron (Fe) were studied. Results: this review presents an analysis of the chemical effects of resveratrol on oxidative stress associated with the exposure of metal compounds. The interaction of resveratrol with the production of reactive oxygen species (ERO's), the endogenous antioxidant system and its effects on DNA damage is discussed. From these studies, a diagram that shows the proposed interactions for resveratrol; heavy metals As, Cd, Cu, Cr and Fe; and oxidative stress is generated. Conclusions: the studies analyzed show that resveratrol is able to modulate the oxidative stress generated by different heavy metal compounds such as As, Cd, Cu, Cr and Fe.

Effects of Shenfu Qiangxin Drink on H2O2-induced oxidative stress, inflammation and apoptosis in neonatal rat cardiomyocytes and possible underlying mechanisms

The aim of the present study was to investigate the effects of Shenfu Qiangxin Drink (SFQXD) on acute myocardial infarction (AMI) and identify the possible underlying mechanisms. Levels of reactive oxygen species (ROS) and inflammatory factors, including interleukin (IL)-6, IL-1β and tumor necrosis factor-α (TNF-α) in the blood samples of patients with AMI were measured using commercially available kits by visible spectrophotometry after SFQXD administration. The contents of phosphorylated (p-) forkhead box O3a (FOXO3a) was examined using an ELISA kit. In addition, a hydrogen peroxide (H₂O₂)-induced myocardial injury model was established in vitro using neonatal rat cardiomyocytes. Following treatment with SFQXD, the levels of intracellular ROS, cell apoptosis, oxidative stress- and inflammation-related markers were measured using commercially available kits by visible spectrophotometry. Additionally, western blot analysis was used to measure the expression of sirtuin-4 (SIRT4), p-FOXO3a, acetylated FOXO3a (ace-FOXO3a) and apoptosis-related genes (Bcl-2, Bax, BIM and cleaved caspase-3). Subsequently, to investigate the possible underlying regulatory mechanisms, SIRT4 expression was silenced by transfection with small hairpin RNA against SIRT4, following which changes in the extent of oxidative stress, inflammation and apoptosis were assessed. The levels of ROS and interleukin (IL)-1β were found to be significantly reduced, whilst FOXO3a phosphorylation was markedly increased following administration with SFQXD. In vitro, SFQXD dose-dependently inhibited H₂O₂-induced oxidative stress, inflammation and apoptosis in neonatal rat cardiomyocytes. In addition, FOXO3a phosphorylation was markedly upregulated whilst FOXO3a acetylation was downregulated following treatment of H₂O₂-induced primary neonatal cardiomyocytes with SFQXD. SIRT4 knockdown also markedly reversed the effects of SFQXD on oxidative stress, inflammation and apoptosis in neonatal rat cardiomyocytes. In conclusion, these findings demonstrated that SFQXD may alleviate oxidative stress-induced myocardial injury by potentially regulating SIRT4/FOXO3a signaling, suggesting that SFQXD may be of clinical value for the treatment of AMI.

The Mitochondrial Permeability Transition: Nexus of Aging, Disease and Longevity

The activity of the mitochondrial permeability transition pore, mPTP, a highly regulated multi-component mega-channel, is enhanced in aging and in aging-driven degenerative diseases. mPTP activity accelerates aging by releasing large amounts of cell-damaging reactive oxygen species, Ca²⁺ and NAD⁺. The various pathways that control the channel activity, directly or indirectly, can therefore either inhibit or accelerate aging or retard or enhance the progression of aging-driven degenerative diseases and determine lifespan and healthspan. Autophagy, a catabolic process that removes and digests damaged proteins and organelles, protects the cell against aging and disease. However, the protective effect of autophagy depends on mTORC2/SKG1 inhibition of mPTP. Autophagy is inhibited in aging cells. Mitophagy, a specialized form of autophagy, which retards aging by removing mitochondrial fragments with activated mPTP, is also inhibited in aging cells, and this inhibition leads to increased mPTP activation, which is a major contributor to neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. The increased activity of mPTP in aging turns autophagy/mitophagy into a destructive process leading to cell aging and death. Several drugs and lifestyle modifications that enhance healthspan and lifespan enhance autophagy and inhibit the activation of mPTP. Therefore, elucidating the intricate connections between pathways that activate and inhibit mPTP, in the context of aging and degenerative diseases, could enhance the discovery of new drugs and lifestyle modifications that slow aging and degenerative disease.

Ameliorative effects of resveratrol against cadmium-induced nephrotoxicity via modulating nuclear xenobiotic receptor response and PINK1/Parkin-mediated Mitophagy

Cadmium (Cd) is a toxic pollutant with high nephrotoxicity in the agricultural environment. Resveratrol has been found to have a renoprotective effect but the underlying mechanisms of this have not yet been fully elucidated. The aim of this study is to illustrate the antagonism of resveratrol against Cd-induced nephrotoxicity. A total of 80 birds were divided randomly into 4 groups and treated via diet for 90 days as follows: control group (Con); 400 mg kg-1 resveratrol group (Resv); 140 mg kg-1 Cd group (Cd 140); and 140 mg kg-1 Cd + 400 mg kg-1 resveratrol group (Cd + Resv). It was observed that resveratrol treatment dramatically alleviated Cd-induced histopathological lesions of the kidney. Simultaneously, resveratrol mitigated Cd-induced oxidative stress by reducing MDA and H2O2 production, alleviating GSH depletion and restoring the activity of antioxidant enzymes (T-SOD, Cu-Zn SOD, CAT, GST and GSH-Px). Resveratrol activated NXRs (CAR/PXR/AHR/Nrf2) signaling pathways and exerted antidotal roles by enhancing the phase I and II detoxification systems to relieve oxidative damage. Moreover, resveratrol ameliorated Cd-induced ultrastructural abnormality and mitochondria dysfunction by recovering mitochondrial function-related factors VDAC1, Cyt C and Sirt3 upregulation and Sirt1, PGC-1α, Nrf1 and TFAM transcription restrictions. Resveratrol attenuated Cd-induced excessive mitochondrial fission and promoted mitochondrial fusion, which reversed PINK1/Parkin-mediated mitophagy initiation. Collectively, our findings explicate the potential protection against Cd-induced nephrotoxicity and mitochondria damage.

Notoginseng Leaf Triterpenes Ameliorates OGD/R-Induced Neuronal Injury via SIRT1/2/3-Foxo3a-MnSOD/PGC-1α Signaling Pathways Mediated by the NAMPT-NAD Pathway

Background

Cerebral ischemic stroke (CIS) is a common cerebrovascular disease whose main risks include necrosis, apoptosis, and cerebral infarction. But few therapeutic advances and prominent drugs seem to be of value for ischemic stroke in the clinic yet. In the previous study, notoginseng leaf triterpenes (PNGL) from Panax notoginseng stem and leaf have been confirmed to have neuroprotective effects against mitochondrial damages caused by cerebral ischemia in vivo. However, the potential mechanisms of mitochondrial protection have not been fully elaborated yet.

Methods

The oxygen and glucose deprivation and reperfusion (OGD/R)-induced SH-SY5Y cells were adopted to explore the neuroprotective effects and the potential mechanisms of PNGL in vitro. Cellular cytotoxicity was measured by MTT, viable mitochondrial staining, and antioxidant marker detection in vitro.Mitochondrial functions were analyzed by ATP content measurement, MMP determination, ROS, NAD, and NADH kit in vitro. And the inhibitor FK866 was adopted to verify the regulation of PNGL on the target NAMPT and its key downstream.

Results

In OGD/R models, treatment with PNGL strikingly alleviated ischemia injury, obviously preserved redox balance and excessive oxidative stress, inhibited mitochondrial damage, markedly alleviated energy metabolism dysfunction, improved neuronal mitochondrial functions, obviously reduced neuronal loss and apoptosis in vitro, and thus notedly raised neuronal survival under ischemia and hypoxia. Meanwhile, PNGL markedly increased the expression of nicotinamide phosphoribosyltransferase (NAMPT) in the ischemic regions and OGD/R-induced SH-SY5Y cells and regulated the downstream SIRT1/2-Foxo3a and SIRT1/3-MnSOD/PGC-1α pathways. And FK866 further verified that the protective effects of PNGL might be mediated by the NAMPT in vitro.

Conclusions

The mitochondrial protective effects of PNGL are, at least partly, mediated via the NAMPT-NAD+ and its downstream SIRT1/2/3-Foxo3a-MnSOD/PGC-1α signaling pathways. PNGL, as a new drug candidate, has a pivotal role in mitochondrial homeostasis and energy metabolism therapy via NAMPT against OGD-induced SH-SY5Y cell injury.

FOXO3a accumulation and activation accelerate oxidative stress-induced podocyte injury

Podocyte injury is the primary cause of glomerular injury in diabetic nephropathy (DN). Advanced oxidation protein products (AOPPs), the triggers and markers of oxidative stress in DN, have been linked to podocyte damage. However, the underlying mechanism is not yet clear. Here, we investigated the potential role of FOXO3a, a key transcription factor in the response to stress, in mediating AOPPs-induced podocyte injury. We found that FOXO3a expression was increased in the glomeruli of kidney biopsies from patients with DN and it was positively correlated with proteinuria. The serum from patients with DN significantly increased FOXO3a and its downstream genes FasL and Bim, thereby inducing the high level of cleaved caspase3 and the loss of nephrin and podocin expressions in podocytes. Blockade of AOPPs signaling by a neutralizing antibody against the receptor of advanced glycation end products (αRAGE) abolished the effect of DN serum on podocytes, confirming the pathogenic role of AOPPs in DN serum. Downregulation of FOXO3a decreased AOPPs-induced podocyte apoptosis and restored the levels of podocyte markers nephrin and podocin, and upregulation of FOXO3a exacerbated these changes in podocytes after AOPPs treatment. Furthermore, FOXO3a specifically activated proapoptotic genes in podocytes only in the presence of AOPPs. Mechanistically, AOPPs increased the FOXO3a protein levels by inhibiting their autophagic degradation in a ROS/mTOR-dependent manner. Moreover AOPPs activated the accumulated FOXO3a by maintaining FOXO3a in the nucleus, and this process was dependent on ROS-mediated AKT signaling deactivation. These studies suggest that FOXO3a plays a critical role in mediating AOPPs-induced podocyte injury and reveal a new mechanistic linkage of oxidative stress, FOXO3a activation and podocyte injury in DN.

Hepatocyte growth factor (HGF) and stem cell factor (SCF) maintained the stemness of human bone marrow mesenchymal stem cells (hBMSCs) during long-term expansion by preserving mitochondrial function via the PI3K/AKT, ERK1/2, and STAT3 signaling pathways

Background

Mesenchymal stem cells (MSCs) have a limited self-renewal ability, impaired multi-differentiation potential, and undetermined cell senescence during in vitro series expansion. To address this concern, we investigated the effects of the microenvironment provided by stem cells from human exfoliated deciduous teeth (SHED) in maintaining the stemness of human bone marrow mesenchymal stem cells (hBMSCs) and identified the key factors and possible mechanisms responsible for maintaining the stemness of MSCs during long-term expansion in vitro.

Methods

The passage 3 (P3) to passage 8 (P8) hBMSCs were cultured in the conditioned medium from SHED (SHED-CM). The percentage of senescent cells was evaluated by β-galactosidase staining. In addition, the osteogenic differentiation potential was analyzed by reverse transcription quantitative PCR (RT-qPCR), Western blot, alizarin red, and alkaline phosphatase (ALP) staining. Furthermore, RT-qPCR results identified hepatocyte growth factor (HGF) and stem cell factor (SCF) as key factors. Thus, the effects of HGF and SCF on mitochondrial function were assessed by measuring the ROS and mitochondrial membrane potential levels. Finally, selected mitochondrial-related proteins associated with the PI3K/AKT, ERK1/2, and STAT3 signaling pathways were investigated to determine the effects of HGF and SCF in preserving the mitochondrial function of hBMSCs during long-term expansion.

Results

SHED-CM had significantly enhanced the cell proliferation, reduced the senescent cells, and maintained the osteogenesis and pro-angiogenic capacity in P8 hBMSCs during long-term expansion. In addition, hBMSCs treated with 100 ng/ml HGF and 10 ng/ml SCF had reduced ROS levels and preserved mitochondrial membrane potential compared with P8 hBMSCs during long-term expansion. Furthermore, HGF and SCF upregulated the expression of mitochondrial-related proteins associated with the PI3K/AKT, ERK1/2, and STAT3 signaling pathways, possibly contributing to the maintenance of hBMSCs stemness by preserving mitochondrial function.

Conclusion

Both HGF and SCF are key factors in maintaining the stemness of hBMSCs by preserving mitochondrial function through the expression of proteins associated with the PI3K/AKT, ERK1/2, and STAT3 signaling pathways. This study provides new insights into the anti-senescence capability of HGF and SCF, as well as new evidence for their potential application in optimizing the long-term culture of MSCs.

SIRT3 Transfection of Aged Human Bone Marrow-Derived Mesenchymal Stem Cells Improves Cell Therapy-Mediated Myocardial Repair

Sirtuin 3 (SIRT3) is a deacetylase important for antioxidant protection, cell longevity, and aging. We hypothesized that SIRT3 improve oxidative resistance of aged cells and improve cell therapy in aged patients. In vitro, the proliferation and oxidative resistance of human mesenchymal stem cells (hMSCs) significantly declined with age. The expression and activity of antioxidant enzymes, including catalase (CAT) and manganese superoxide dismutase (MnSOD), increased after transfection of SIRT3 in hMSCs from older donors (O-hMSCs). The protein level of Forkhead box O3a (FOXO3a) in nucleus increased after SIRT3 overexpression. The antioxidant capacity of O-hMSCs increased after SIRT3 overexpression. 3-Amino-1,2,4-triazole (3-AT, CAT inhibitor) or diethyldithiocarbamate (DETC, SOD inhibitor) that was used to inhibit CAT or SOD activity significantly blocked the antioxidant function of SIRT3. When two inhibitors were used together, the antioxidant function of SIRT3 almost disappeared. Following myocardial infarction and intramyocardial injections of O-hMSCs in rats in vivo, the survival rate of O-hMSCs increased by SIRT3 transfection. The cardiac function of rats was improved after SIRT3-overexpressed O-hMSC transplantation. The infarct size, collagen content, and expression levels of matrix metalloproteinase 2 (MMP2) and MMP9 decreased. Besides, the protein level of vascular endothelial growth factor A and vascular density increased after cell transplantation with SIRT3-modified O-hMSCs. These results indicate that damage resistance of hMSCs decline with age and SIRT3 might protect O-hMSCs against oxidative damage by activating CAT and MnSOD through transferring FOXO3a into nucleus. Meanwhile, the therapeutic effect of aged hMSC transplantation can be improved by SIRT3 overexpression.

Sirtuins and intervertebral disc degeneration: Roles in inflammation, oxidative stress, and mitochondrial function

Intervertebral disc degeneration (IDD) is one of the main causes of low back pain, which seriously reduces the quality of life of patients and places a heavy economic burden on their families. Cellular senescence is considered to be an important factor leading to IDD, and inflammatory response, oxidative stress, and mitochondrial dysfunction are closely related to intervertebral disc (IVD) senescence. Therefore, inhibition of the inflammatory response and oxidative stress, along with maintaining mitochondrial function, may be useful in treating IDD. The sirtuins are a family of evolutionarily conserved nicotinamide adenine dinucleotide (NAD⁺)-dependent histone deacetylases, which are the major molecules mediating life extension or delay of aging-related diseases. The sirtuin protein family consist of seven members (SIRT1 - 7), which are mainly involved in various aging-related diseases by regulating inflammation, oxidative stress, and mitochondrial function. Among them, SIRT1, SIRT2, SIRT3, and SIRT6 are closely related to IDD. In addition, some activators of sirtuin proteins, such as resveratrol, melatonin, magnolol, 1,4-dihydropyridine (DHP), SRT1720, and nicotinamide mononucleotide (NMN), have been evaluated in preclinical studies for their effects in preventing IDD. This review described the biological functions of sirtuins and the important roles of SIRT1, SIRT2, SIRT3, and SIRT6 in IDD by regulating oxidative stress, inflammatory response, and mitochondrial function. In addition, we introduce the status of some sirtuin activators in IDD preclinical studies. This review will provide a background for further clarification of the molecular mechanism underlying IDD and the development of potential therapeutic drugs.

Therapeutical properties of Mimosa caesalpiniifolia in rat liver intoxicated with cadmium

The aim of this study was to evaluate the therapeutic properties of Mimosa caesalpiniifolia in liver of rats exposed to cadmium under morphological, oxidative, inflammatory, and mutagenic parameters. A total of 40 Wistar rats (90 days, ~ 250 g) were distributed into eight groups (n = 5) as follows: (i) control; (ii) cadmium: cadmium chloride injection at 1.2 mg/kg; (iii) Mimosa extract: treatment with Mimosa extract at 250 mg/kg; (iv) Mimosa fraction: treatment with Mimosa acetate fraction at 62.5 mg/kg; (v) cadmium and Mimosa extract 62.5: submitted to cadmium chloride at 1.2 mg/kg injection and treatment with Mimosa extract at 62.5 mg/kg; (vi) cadmium and Mimosa extract 125: subjected to cadmium chloride at 1.2 mg/kg injection and treatment with Mimosa extract at 125 mg/kg; (vii) cadmium and Mimosa 250 extract: submitted to cadmium chloride 1.2 mg/kg injection and treatment with Mimosa extract at 250 mg/kg; (viii) cadmium treated with fraction of Mimosa acetate: submitted to cadmium chloride 1.2 mg/kg injection and treatment with acetate fraction of Mimosa extract at 62.5 mg/kg. In the animals intoxicated with cadmium and treated with fraction [62.5], increased expression of SOD-Mn reduced frequency of binucleated hepatocytes, karyolysis, and karyorrhexis, besides the antimutagenic and antioxidant action. The extract [62.5] was cytoprotective, antimutagenic, and reduced karyolysis. The extract [125] was cytoprotective, antioxidant, antifibrotic, anti-inflammatory, and reduced frequency of binucleated hepatocytes, while extract [250] was cytotoxic and mutagenic. In summary, the extract of Mimosa exerts some therapeutic properties in hepatic tissue after Cd intoxication, but only when it is administrated at intermediate doses. Probably, a high content of polyphenols in the EHM [250] and Fr-EtOAc groups exert pro-oxidant activities in the liver particularly when associated with Cd.

Transgenerational Effects of Periconception Heavy Metal Administration on Adipose Weight and Glucose Homeostasis in Mice at Maturity

We previously demonstrated that periconception maternal administration (2 mg/kg body weight each) of cadmium chloride (CdCl2) plus methylmercury (II) chloride (CH3HgCl) impaired glucose homeostasis and increased body weights and abdominal adipose tissue weight of male offspring in the F1 generation. However, transgenerational effects of this exposure have not been studied. Therefore, the effects of periconception Cd+Hg administration on indices of chronic diseases at adulthood in F2-F4 generations were examined. Male and female progeny of Cd+Hg periconceptionally treated females, and offspring of vehicle control females were bred with naïve CD1 mice to obtain F2 offspring, with additional crosses as above to the F4 generation (F1-F4 animals were not administered Cd+Hg). Birth weights and litter size were similar in all generations. Indices of impaired glucose homeostasis were observed in matrilineally descended F2 male offspring, including reduced glucose tolerance, along with increased basal phosphorylation of insulin receptor substrate 1 (IRS1) at serine 307 suggesting altered insulin signaling. Reduced glucose tolerance was also seen in F4 males. Increased body weight and/or abdominal adiposity were observed through the F4 generation in males descended matrilineally from the treated female progenitors. Patrilineally derived F2 females displayed reduced glucose tolerance. Females (F2) patrilineally and matrilineally derived displayed significant kidney enlargement. Periconception administration of cadmium and mercury caused persistent transgenerational effects in offspring through the F4 generation in the absence of continued toxicant exposure, with persistent transgenerational effects inherited specifically through the matrilineal germline.

Research progress on sirtuins family members and cell senescence

Human aging is a phenomenon of gradual decline and loss of cell, tissue, organ and other functions under the action of external environment and internal factors. It is mainly related to genomic instability, telomere wear, mitochondrial dysfunction, protein balance disorder, antioxidant damage, microRNA expression disorder and so on. Sirtuins protein is a kind of deacetylase which can regulate cell metabolism and participate in a variety of cell physiological functions. It has been found that sirtuins family can prolong the lifespan of yeast. Sirtuins can inhibit human aging through many signaling pathways, including apoptosis signaling pathway, mTOR signaling pathway, sirtuins signaling pathway, AMPK signaling pathway, phosphatidylinositol 3 kinase (PI3K) signaling pathway and so on. Based on this, this paper reviews the action principle of anti-aging star members of sirtuins family Sirt1, Sirt3 and Sirt6 on anti-aging related signaling pathways and typical compounds, in order to provide ideas for the screening of anti-aging compounds of sirtuins family members.

The Role of Natural Antioxidants Against Reactive Oxygen Species Produced by Cadmium Toxicity: A Review

Cadmium (Cd) is a significant ecotoxic heavy metal that adversely affects all biological processes of humans, animals and plants. Exposure to acute and chronic Cd damages many organs in humans and animals (e.g. lung, liver, brain, kidney, and testes). In humans, the Cd concentration at birth is zero, but because the biological half-life is long (about 30 years in humans), the concentration increases with age. The industrial developments of the last century have significantly increased the use of this metal. Especially in developing countries, this consumption is higher. Oxidative stress is the imbalance between antioxidants and oxidants. Cd increases reactive oxygen species (ROS) production and causes oxidative stress. Excess cellular levels of ROS cause damage to proteins, nucleic acids, lipids, membranes and organelles. This damage has been associated with various diseases. These include cancer, hypertension, ischemia/perfusion, cardiovascular diseases, chronic obstructive pulmonary disease, diabetes, insulin resistance, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, asthma, skin diseases, chronic kidney disease, eye diseases, neurodegenerative diseases (amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and Huntington disease). Natural antioxidants are popular drugs that are used by the majority of people and have few side effects. Natural antioxidants play an important role in reducing free radicals caused by Cd toxicity. Our goal in this review is to establish the relationship between Cd and oxidative stress and to discuss the role of natural antioxidants in reducing Cd toxicity.

Transcription Factors and Downstream Genes in Cadmium Toxicity

Cadmium (Cd) is a harmful heavy metal widely present in the environment which can cause severe kidney damage. The proximal tubular cells are the main target of renal Cd toxicity. The consequences of Cd cytotoxicity involve apoptosis and necrosis. Recently, we and others have focused on how Cd affects transcription factors and the regulation of their target genes. Those studies showed that transcription factors initiate numerous pathways upon Cd exposure, leading to apoptosis, autophagic cell death, disruption of cell-cell adhesion, and generation of mitochondrial reactive oxygen species. Of particular note, Cd induces endoplasmic reticulum stress, resulting in not only apoptosis but also autophagic dysregulation, which can trigger cell damage. In some cases, however, Cd-regulated transcription factors can induce cell survival signaling. This review centers on our own research to elucidate the transcription factor-downstream gene cascades that are central to Cd-induced renal toxicity.

Pseudomonas aeruginosa Induced Host Epithelial Cell Mitochondrial Dysfunction

The pathogenicity of P. aeruginosa is dependent on quorum sensing (QS), an inter-bacterial communication system that can also modulate host biology. The innate immune function of the lung mucosal barrier is dependent on proper mitochondrial function. The purpose of this study was to define the mechanism by which bacterial factors modulate host lung epithelial cell mitochondrial function and to investigate novel therapies that ameliorate this effect. 3-oxo-C12-HSL disrupts mitochondrial morphology, attenuates mitochondrial bioenergetics, and induces mitochondrial DNA oxidative injury. Mechanistically, we show that 3-oxo-C12-HSL attenuates expression of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), a master regulator of mitochondrial biogenesis, antioxidant defense, and cellular respiration, and its downstream effectors in both BEAS-2B and primary lung epithelial cells. Overexpression of PGC-1α attenuates the inhibition in cellular respiration caused by 3-oxo-C12-HSL. Pharmacologic activation of PGC-1α restores barrier integrity in cells treated with 3-oxo-C12-HSL. These data demonstrate that the P. aeruginosa QS molecule, 3-oxo-C12-HSL, alters mitochondrial pathways critical for lung mucosal immunity. Genetic and pharmacologic strategies that activate the PGC-1α pathway enhance host epithelial cell mitochondrial function and improve the epithelial innate response to P. aeruginosa. Therapies that rescue PGC-1α function may provide a complementary approach in the treatment of P. aeruginosa infection.

Health Benefits of Resveratrol in Kidney Disease: Evidence from In Vitro and In Vivo Studies

Different diseases and disorders that affect the kidneys include, but are not limited to, glomerulonephritis, diabetic nephropathy, polycystic kidney disease, kidney stones, renal fibrosis, sepsis, and renal cell carcinoma. Kidney disease tends to develop over many years, making it difficult to identify until much later when kidney function is severely impaired and undergoing kidney failure. Although conservative care, symptom management, medication, dialysis, transplantation, and aggressive renal cancer therapy are some of the current strategies/approaches to kidney disease treatment, new preventative targeted therapies are needed. Epidemiological studies have suggested that a diet rich in fruits and vegetables is associated with health benefits including protection against kidney disease and renal cancer. Resveratrol, a polyphenol found in grapes and berries, has been reported to have antioxidant, anti-inflammatory, antidiabetic, hepatoprotective, neuroprotective, and anti-cancer properties. The current review summarizes the existing in vitro and in vivo animal and human studies examining the nephroprotective effects of resveratrol.

Trans sodium crocetinate alleviates ischemia/reperfusion-induced myocardial oxidative stress and apoptosis via the SIRT3/FOXO3a/SOD2 signaling pathway

Trans sodium crocetinate (TSC) has been reported to exert a protective effect against cerebral ischemia/reperfusion (I/R) injury. However, whether TSC protects against myocardial ischemia/reperfusion (MI/R) injury remains unknown. Herein, we found that TSC treatment reduced myocardial infract size and elevated serum LDH and CK activities of MI/R rats. TSC administration attenuated oxidative stress in MI/R rats and H9C2 cells exposed to oxygen glucose deprivation/reperfusion (OGD/R). TSC administration relieved I/R-induced myocardial apoptosis in vivo and in vitro, as evidenced by reduced number of TUNEL positive cells, accompanying with marked decreases in caspase-3 activity and Bax protein level and an increase in Bcl-2 protein level. TSC treatment markedly increased SIRT3 activity and SIRT3 and SOD2 protein levels, and could also diminished the phosphorylation of FOXO3a protein. Additionally, TSC treatment attenuated the acetylation of FOXO3a and SOD2 protein. But, these effects were obviously blocked by SIRT3 knockdown. Besides, SIRT3 knockdown blocked the cardioprotective effect of TSC on OGD/R-induced oxidative stress, apoptosis and mitochondrial dysfunction in vitro. In summary, TSC alleviates I/R-induced myocardial oxidative stress and apoptosis via the SIRT3/FOXO3a/SOD2 signaling pathway. Our study suggests that TSC may become a novel drug for the treatment of MI/R injury.

Sirtuin3 deficiency exacerbates carbon tetrachloride-induced hepatic injury in mice

Sirtuin3 (SIRT3) plays an important role in maintaining normal mitochondrial function and alleviating oxidative stress. After carbon tetrachloride (CCl₄ ) administration, the expression of SIRT3 decreased in the liver of mice, which indicated that the SIRT3 might play a crucial role during chemical-induced acute hepatic injury. To verify the hypothesis, CCl ₄ was given to induce acute hepatic injury in SIRT3 knockout (KO) mice and wild-type (WT) mice. CCl ₄ -induced liver injury was more severe in SIRT3 KO mice compared with the WT mice. In addition, the oxidative stress induced by CCl ₄ was enhanced in the SIRT3 KO mice. Furthermore, the increased expression of dynamin-related protein 1 was also aggravated in SIRT3 KO mice after CCl ₄ administration. In conclusion, our study demonstrated that SIRT3 deficiency exacerbated CCl ₄ -induced impairment of the liver in mice, and the mechanism might be related to enhanced oxidative stress.

Cytoprotective Effects of Natural Compounds against Oxidative Stress

Oxidative stress, an imbalance between reactive oxygen species and antioxidants, has been witnessed in pathophysiological states of many disorders. Compounds identified from natural sources have long been recognized to ameliorate oxidative stress due to their inherent antioxidant activities. Here, we summarize the cytoprotective effects and mechanisms of natural or naturally derived synthetic compounds against oxidative stress. These compounds include: caffeic acid phenethyl ester (CAPE) found in honey bee propolis, curcumin from turmeric roots, resveratrol abundant in grape, and 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole (CDDO-Im), a synthetic triterpenoid based on naturally occurring oleanolic acid. Cytoprotective effects of these compounds in diseases conditions like cardiovascular diseases and obesity to decrease oxidative stress are discussed.

Protective Effects of Quercetin Against Cadmium Chloride-Induced Oxidative Injury in Goat Sperm and Zygotes

Quercetin, a plant-derived flavonoid, is frequently used as an antioxidant for efficient anti-oxidative capacity. However, whether quercetin has protective effects on goat sperm and preimplantation embryos against Cd²⁺-induced oxidative injury is still unclear. So, we researched the influence of quercetin on goat sperm and zygotes respectively under the oxidative stress induced by Cd²⁺. In our study, quercetin decreased the malonaldehyde (MDA) and reactive oxygen species (ROS) levels caused by Cd²⁺ in goat sperm (p < 0.05), which facilitated sperm characteristics including motility, survival rates, membrane integrity, and mitochondria activity during storage in vitro and subsequent embryo development (p < 0.05). Moreover, in goat zygotes, quercetin decreased peroxidation products including ROS, MDA, and carbonyl through preserving or maintaining mitochondrial function, gene expression, and anti-oxidative products such as glutathione peroxidase, superoxide dismutase, and catalase, which ameliorated subsequent embryo development and embryo quality (p < 0.05). Taken together, these results suggest that quercetin protects both goat sperm and preimplantation embryos from Cd²⁺-induced oxidative stress.

Melatonin-mediated upregulation of Sirt3 attenuates sodium fluoride-induced hepatotoxicity by activating the MT1-PI3K/AKT-PGC-1α signaling pathway

Mitochondrial reactive oxygen species (ROS) production has been implicated in the pathogenesis of fluoride toxicity in liver. Melatonin, an indolamine synthesized in the pineal gland, was previously shown to protect against sodium fluoride (NaF)-induced hepatotoxicity. This study investigated the protective effects of melatonin pretreatment on NaF-induced hepatotoxicity and elucidates the potential mechanism of melatonin-mediated protection. Reducing mitochondrial ROS by melatonin substantially attenuated NaF-induced NADPH oxidase 4 (Nox4) upregulation and cytotoxicity in L-02 cells. Melatonin exerted its hepatoprotective effects by upregulating Sirtuin 3 (Sirt3) expression level and its activity. Melatonin increased the activity of manganese superoxide dismutase (SOD2) by promoting Sirt3-mediated deacetylation and promoted SOD2 expression through Sirt3-regulated DNA-binding activity of forkhead box O3 (FoxO3a), thus inhibiting the production of mitochondrial ROS induced by NaF. Notably, increased peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) by melatonin activated the Sirt3 expression, which was regulated by an estrogen-related receptor (ERR) binding element (ERRE) mapped to Sirt3 promoter region. Analysis of the cell signaling pathway profiling systems and specific pathway inhibition indicated that melatonin enhances PGC-1α expression by activating the PI3K/AKT signaling pathway. Importantly, inhibition of melatonin receptor (MT)-1 blocked the melatonin-activated PI3K/AKT-PGC-1α-Sirt3 signaling. Mechanistic study revealed that the protective effects of melatonin were associated with down-regulation of JNK1/2 phosphorylation. Our findings provided a theoretical basis that melatonin mitigated NaF-induced hepatotoxicity, which, in part, was mediated through the activation of the Sirt3 pathway.

A Critical Assessment of the Therapeutic Potential of Resveratrol Supplements for Treating Mitochondrial Disorders

In human cells, mitochondria provide the largest part of cellular energy in the form of adenosine triphosphate generated by the process of oxidative phosphorylation (OXPHOS). Impaired OXPHOS activity leads to a heterogeneous group of inherited diseases for which therapeutic options today remain very limited. Potential innovative strategies aim to ameliorate mitochondrial function by increasing the total mitochondrial load of tissues and/or to scavenge the excess of reactive oxygen species generated by OXPHOS malfunctioning. In this respect, resveratrol, a compound that conveniently combines mitogenetic with antioxidant activities and, as a bonus, possesses anti-apoptotic properties, has come forward as a promising nutraceutical. We review the scientific evidence gathered so far through experiments in both in vitro and in vivo systems, evaluating the therapeutic effect that resveratrol is expected to generate in mitochondrial patients. The obtained results are encouraging, but clearly show that achieving normalization of OXPHOS function with this strategy alone could prove to be an unattainable goal.