Role of mitochondrial dysfunction and altered autophagy in cardiovascular aging and disease: from mechanisms to therapeutics

Circ_002033 Regulates Proliferation, Apoptosis, and Oxidative Damage of Bovine Mammary Epithelial Cells via the miR-199a-5p-MAP3K11 Axis in Heat Stress

Heat stress is becoming the major factor regarding dairy cow health and milk quality because of global warming. Circular RNAs (circRNAs) represent a special type of noncoding RNAs, which are related to regulating many biological processes. Nonetheless, little is known concerning their effects on heat-stressed bovine mammary epithelial cells (BMECs). Here, this study found a novel circRNA, circ_002033, using RNA sequencing (RNA-seq) and explored the role and underlying regulatory mechanism in proliferation, apoptosis, and oxidative damage in a heat-stressed bovine mammary epithelial cell line (MAC-T). According to the previous RNA-seq analysis, the abundance of circ_002033 in mammary gland tissue of heat-stressed cows increased relative to nonheat-stressed counterparts. This study found that the knockdown of circ_002033 promoted proliferation and alleviated apoptosis and oxidative damage in heat-stressed MAC-T. Mechanistically, circ_002033 localizes to miR-199a-5p in the cytoplasm of MAC-T to regulate mitogen-activated protein kinase kinase 11 (MAP3K11) expression. Meanwhile, miR-199a-5p and MAP3K11 are also involved in regulating the proliferation and apoptosis of heat-stressed MAC-T. Importantly, circ_002033 knockdown promoted the expression of miR-199a-5p while decreasing that of MAP3K11, thereby enhancing proliferation while alleviating apoptosis and oxidative damage in heat-stressed MAC-T. In summary, we found that circ_002033 regulates the proliferation, apoptosis, and oxidative damage of heat-stressed BMECs through the miR-199a-5p/MAP3K11 axis, providing the theoretical molecular foundation for mitigating heat stress of dairy cows.

Mitochondrial Dysfunction: A Roadmap for Understanding and Tackling Cardiovascular Aging

Cardiovascular aging is a progressive remodeling process constituting a variety of cellular and molecular alterations that are closely linked to mitochondrial dysfunction. Therefore, gaining a deeper understanding of the changes in mitochondrial function during cardiovascular aging is crucial for preventing cardiovascular diseases. Cardiac aging is accompanied by fibrosis, cardiomyocyte hypertrophy, metabolic changes, and infiltration of immune cells, collectively contributing to the overall remodeling of the heart. Similarly, during vascular aging, there is a profound remodeling of blood vessel structure. These remodeling present damage to endothelial cells, increased vascular stiffness, impaired formation of new blood vessels (angiogenesis), the development of arteriosclerosis, and chronic vascular inflammation. This review underscores the role of mitochondrial dysfunction in cardiac aging, exploring its impact on fibrosis and myocardial alterations, metabolic remodeling, immune response remodeling, as well as in vascular aging in the heart. Additionally, we emphasize the significance of mitochondria-targeted therapies in preventing cardiovascular diseases in the elderly.

Future perspectives on the roles of mitochondrial dynamics in the heart in obesity and aging

Increasing global obesity rates and an aging population are independently linked to cardiac complications. Consequently, it is crucial to comprehensively understand the mechanisms behind these conditions to advance innovative therapies for age-related diseases. Mitochondrial dysfunction, specifically defects in mitochondrial fission/fusion processes, has emerged as a central regulator of cardiac complications in aging and age-related diseases (e.g., obesity). Since excessive fission and impaired fusion of cardiac mitochondria lead to disruptions in mitochondrial dynamics and cellular metabolism in aging and obesity, modulating mitochondrial dynamics with either fission inhibitors or fusion promoters has offered cardioprotection against these pathological conditions in preclinical models. This review explores the molecular mechanisms governing mitochondrial dynamics as well as the disturbances observed in aging and obesity. Additionally, pharmaceutical interventions that specifically target the processes of mitochondrial fission and fusion are presented and discussed. By establishing a connection between mitochondrial dynamism through fission and fusion and the advancement or mitigation of age-related diseases, particularly obesity, this review provides valuable insights into the progression and potential prevention strategies for such conditions.

Berberine modulates cardiovascular diseases as a multitarget-mediated alkaloid with insights into its downstream signals using in silico prospective screening approaches

Atherosclerosis is potentially correlated with several cardiac disorders that are greatly associated with cellular oxidative stress generation, inflammation, endothelial cells dysfunction, and many cardiovascular complications. Berberine is a natural isoquinoline alkaloid compound that widely modulates pathogenesis of atherosclerosis through its different curative potentials. This in silico screening study was designed to confirm the potent restorative properties of berberine chloride as a multitarget-mediated alkaloid against the CVDs and their complications through screening, identifying, visualizing, and evaluating its binding models, affinities, and interactions toward several CVDs-related targets as direct and/or indirect-mediated signals via inhibiting cellular ER stress and apoptotic signals and activating autophagy pathway. The drug-likeness properties of berberine were predicted using the computational QSAR/ADMET and Lipinski's RO5 analyses as well as in silico molecular docking simulations. The potent berberine-binding modes, residues-interaction patterns, and free energies of binding scores towards several CVDs-related targets were estimated using molecular docking tools. Furthermore, the pharmacokinetic properties and toxicological features of berberine were clearly determined. According to this in silico virtual screening study, berberine chloride could restore cardiac function and improve pathogenic features of atherosclerotic CVDs through alleviating ER stress and apoptotic signals, activating autophagy, improving insulin sensitivity, decreasing hyperglycemia and dyslipidemia, increasing intracellular RCT signaling, attenuating oxidative stress and vascular inflammation, and upregulating cellular antioxidant defenses in many cardiovascular tissues. In this in silico study, berberine chloride greatly modulated several potent CVDs-related targets, including SIGMAR1, GRP78, CASP3, BECN1, PIK3C3, SQSTM1/p62, LC3B, GLUT3, INSR, LDLR, LXRα, PPARγ, IL1β, IFNγ, iNOS, COX-2, MCP-1, IL10, GPx1, and SOD3.

Kynurenines, Neuronal Excitotoxicity, and Mitochondrial Oxidative Stress: Role of the Intestinal Flora

The intestinal flora has been the focus of numerous investigations recently, with inquiries not just into the gastrointestinal aspects but also the pathomechanism of other diseases such as nervous system disorders and mitochondrial diseases. Mitochondrial disorders are the most common type of inheritable metabolic illness caused by mutations of mitochondrial and nuclear DNA. Despite the intensive research, its diagnosis is usually difficult, and unfortunately, treating it challenges physicians. Metabolites of the kynurenine pathway are linked to many disorders, such as depression, schizophrenia, migraine, and also diseases associated with impaired mitochondrial function. The kynurenine pathway includes many substances, for instance kynurenic acid and quinolinic acid. In this review, we would like to show a possible link between the metabolites of the kynurenine pathway and mitochondrial stress in the context of intestinal flora. Furthermore, we summarize the possible markers of and future therapeutic options for the kynurenine pathway in excitotoxicity and mitochondrial oxidative stress.

Mediterranean Shrub Species as a Source of Biomolecules against Neurodegenerative Diseases

Neurodegenerative diseases are associated with oxidative stress, due to an imbalance in the oxidation-reduction reactions at the cellular level. Various treatments are available to treat these diseases, although they often do not cure them and have many adverse effects. Therefore, it is necessary to find complementary and/or alternative drugs that replace current treatments with fewer side effects. It has been demonstrated that natural products derived from plants, specifically phenolic compounds, have a great capacity to suppress oxidative stress and neutralize free radicals thus, they may be used as alternative alternative pharmacological treatments for pathological conditions associated with an increase in oxidative stress. The plant species that dominate the Mediterranean ecosystems are characterized by having a wide variety of phenolic compound content. Therefore, these species might be important sources of neuroprotective biomolecules. To evaluate this potential, 24 typical plant species of the Mediterranean ecosystems were selected, identifying the most important compounds present in them. This set of plant species provides a total of 403 different compounds. Of these compounds, 35.7% are phenolic acids and 55.6% are flavonoids. The most relevant of these compounds are gallic, vanillic, caffeic, chlorogenic, p-coumaric, and ferulic acids, apigenin, kaempferol, myricitrin, quercetin, isoquercetin, quercetrin, rutin, catechin and epicatechin, which are widely distributed among the analyzed plant species (in over 10 species) and which have been involved in the literature in the prevention of different neurodegenerative pathologies. It is also important to mention that three of these plant species, Pistacea lentiscus, Lavandula stoechas and Thymus vulgaris, have most of the described compounds with protective properties against neurodegenerative diseases. The present work shows that the plant species that dominate the studied geographic area can provide an important source of phenolic compounds for the pharmacological and biotechnological industry to prepare extracts or isolated compounds for therapy against neurodegenerative diseases.

Exposome and unhealthy aging: environmental drivers from air pollution to occupational exposures

The aging population worldwide is facing a significant increase in age-related non-communicable diseases, including cardiovascular and brain pathologies. This comprehensive review paper delves into the impact of the exposome, which encompasses the totality of environmental exposures, on unhealthy aging. It explores how environmental factors contribute to the acceleration of aging processes, increase biological age, and facilitate the development and progression of a wide range of age-associated diseases. The impact of environmental factors on cognitive health and the development of chronic age-related diseases affecting the cardiovascular system and central nervous system is discussed, with a specific focus on Alzheimer's disease, Parkinson's disease, stroke, small vessel disease, and vascular cognitive impairment (VCI). Aging is a major risk factor for these diseases. Their pathogenesis involves cellular and molecular mechanisms of aging such as increased oxidative stress, impaired mitochondrial function, DNA damage, and inflammation and is influenced by environmental factors. Environmental toxicants, including ambient particulate matter, pesticides, heavy metals, and organic solvents, have been identified as significant contributors to cardiovascular and brain aging disorders. These toxicants can inflict both macro- and microvascular damage and many of them can also cross the blood-brain barrier, inducing neurotoxic effects, neuroinflammation, and neuronal dysfunction. In conclusion, environmental factors play a critical role in modulating cardiovascular and brain aging. A deeper understanding of how environmental toxicants exacerbate aging processes and contribute to the pathogenesis of neurodegenerative diseases, VCI, and dementia is crucial for the development of preventive strategies and interventions to promote cardiovascular, cerebrovascular, and brain health. By mitigating exposure to harmful environmental factors and promoting healthy aging, we can strive to reduce the burden of age-related cardiovascular and brain pathologies in the aging population.

The multifaceted benefits of walking for healthy aging: from Blue Zones to molecular mechanisms

Physical activity, including walking, has numerous health benefits in older adults, supported by a plethora of observational and interventional studies. Walking decreases the risk or severity of various health outcomes such as cardiovascular and cerebrovascular diseases, type 2 diabetes mellitus, cognitive impairment and dementia, while also improving mental well-being, sleep, and longevity. Dose-response relationships for walking duration and intensity are established for adverse cardiovascular outcomes. Walking's favorable effects on cardiovascular risk factors are attributed to its impact on circulatory, cardiopulmonary, and immune function. Meeting current physical activity guidelines by walking briskly for 30 min per day for 5 days can reduce the risk of several age-associated diseases. Additionally, low-intensity physical exercise, including walking, exerts anti-aging effects and helps prevent age-related diseases, making it a powerful tool for promoting healthy aging. This is exemplified by the lifestyles of individuals in Blue Zones, regions of the world with the highest concentration of centenarians. Walking and other low-intensity physical activities contribute significantly to the longevity of individuals in these regions, with walking being an integral part of their daily lives. Thus, incorporating walking into daily routines and encouraging walking-based physical activity interventions can be an effective strategy for promoting healthy aging and improving health outcomes in all populations. The goal of this review is to provide an overview of the vast and consistent evidence supporting the health benefits of physical activity, with a specific focus on walking, and to discuss the impact of walking on various health outcomes, including the prevention of age-related diseases. Furthermore, this review will delve into the evidence on the impact of walking and low-intensity physical activity on specific molecular and cellular mechanisms of aging, providing insights into the underlying biological mechanisms through which walking exerts its beneficial anti-aging effects.

In Vivo Ultrafast Doppler Imaging Combined with Confocal Microscopy and Behavioral Approaches to Gain Insight into the Central Expression of Peripheral Neuropathy in Trembler-J Mice

The main human hereditary peripheral neuropathy (Charcot-Marie-Tooth, CMT), manifests in progressive sensory and motor deficits. Mutations in the compact myelin protein gene pmp22 cause more than 50% of all CMTs. CMT1E is a subtype of CMT1 myelinopathy carrying micro-mutations in pmp22. The Trembler-J mice have a spontaneous mutation in pmp22 identical to that present in CMT1E human patients. PMP22 is mainly (but not exclusively) expressed in Schwann cells. Some studies have found the presence of pmp22 together with some anomalies in the CNS of CMT patients. Recently, we identified the presence of higher hippocampal pmp22 expression and elevated levels of anxious behavior in TrJ/+ compared to those observed in wt. In the present paper, we delve deeper into the central expression of the neuropathy modeled in Trembler-J analyzing in vivo the cerebrovascular component by Ultrafast Doppler, exploring the vascular structure by scanning laser confocal microscopy, and analyzing the behavioral profile by anxiety and motor difficulty tests. We have found that TrJ/+ hippocampi have increased blood flow and a higher vessel volume compared with the wild type. Together with this, we found an anxiety-like profile in TrJ/+ and the motor difficulties described earlier. We demonstrate that there are specific cerebrovascular hemodynamics associated with a vascular structure and anxious behavior associated with the TrJ/+ clinical phenotype, a model of the human CMT1E disease.

Mitochondria-targeting EGCG derivatives protect H9c2 cardiomyocytes from H2O2-induced apoptosis: design, synthesis and biological evaluation

Pathologies related to cardiovascular diseases mostly emerge as a result of oxidative stress buildup in cardiomyocytes. The heavy load of mitochondrial oxidative phosphorylation in cardiac tissues corresponds to a surge in oxidative stress leading to mitochondrial dysfunction and cellular apoptosis. Thus, scavenging the reactive oxygen species (ROS) linked to mitochondria can significantly improve cardio-protection. Epigallocatechin-3-gallate (EGCG), the major polyphenol found in green tea has been extensively studied for its profound health-beneficial activities. Herein, we designed and synthesized a series of mitochondrial-targeting EGCG derivatives, namely MitoEGCGn (n = 4, 6, 8) by incorporating triphenylphosphonium ion onto it using different linkers. MitoEGCGn were found to be non-toxic to H9c2 rat cardiomyocyte cells even at higher doses in comparison to its parent molecule EGCG. Interestingly, MitoEGCG4 and MitoEGCG6 protected the H9c2 cardiomyocyte cells from the oxidative damage induced by H2O2 whereas EGCG was found to be toxic and ineffective in protecting the cells from H2O2 damage. MitoEGCG4 and MitoEGCG6 also protected the cells from the H2O2-induced disruption of mitochondrial membrane potential as well as activation of apoptosis as revealed by pro-caspase 3 expression profile, DNA fragmentation assay, and AO/EtBr staining. Taken together, our study shows that the mitochondria targeting EGCG derivatives were able to effectively combat the H2O2-induced oxidative stress in H9c2 cardiomyocytes. They eventually augmented the mitochondrial health of cardiomyocytes by maintaining the mitochondrial function and attenuating apoptosis. Overall, MitoEGCG4 and MitoEGCG6 could provision a cardioprotective role to H9c2 cardiomyocytes at the time of oxidative insults related to mitochondrial dysfunction-associated injuries.

The mitochondrial calcium uniporter (MCU) activates mitochondrial respiration and enhances mobility by regulating mitochondrial redox state

Regulation of mitochondrial redox balance is emerging as a key event for cell signaling in both physiological and pathological conditions. However, the link between the mitochondrial redox state and the modulation of these conditions remains poorly defined. Here, we discovered that activation of the evolutionary conserved mitochondrial calcium uniporter (MCU) modulates mitochondrial redox state. By using mitochondria-targeted redox and calcium sensors and genetic MCU-ablated models, we provide evidence of the causality between MCU activation and net reduction of mitochondrial (but not cytosolic) redox state. Redox modulation of redox-sensitive groups via MCU stimulation is required for maintaining respiratory capacity in primary human myotubes and C. elegans, and boosts mobility in worms. The same benefits are obtained bypassing MCU via direct pharmacological reduction of mitochondrial proteins. Collectively, our results demonstrate that MCU regulates mitochondria redox balance and that this process is required to promote the MCU-dependent effects on mitochondrial respiration and mobility.

Non-coding RNAs regulating mitochondrial function in cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of disease-related death worldwide and a significant obstacle to improving patients' health and lives. Mitochondria are core organelles for the maintenance of myocardial tissue homeostasis, and their impairment and dysfunction are considered major contributors to the pathogenesis of various CVDs, such as hypertension, myocardial infarction, and heart failure. However, the exact roles of mitochondrial dysfunction involved in CVD pathogenesis remain not fully understood. Non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, have been shown to be crucial regulators in the initiation and development of CVDs. They can participate in CVD progression by impacting mitochondria and regulating mitochondrial function-related genes and signaling pathways. Some ncRNAs also exhibit great potential as diagnostic and/or prognostic biomarkers as well as therapeutic targets for CVD patients. In this review, we mainly focus on the underlying mechanisms of ncRNAs involved in the regulation of mitochondrial functions and their role in CVD progression. We also highlight their clinical implications as biomarkers for diagnosis and prognosis in CVD treatment. The information reviewed herein could be extremely beneficial to the development of ncRNA-based therapeutic strategies for CVD patients.

Waterpipe smoke inhalation potentiates cardiac oxidative stress, inflammation, mitochondrial dysfunction, apoptosis and autophagy in experimental hypertension

Cigarette smoking worsens the health of hypertensive patients. However, less is known about the actions and underlying mechanisms of waterpipe smoke (WPS) in hypertension. Therefore, we evaluated the effects of WPS inhalation in mice made hypertensive (HT) by infusing angiotensin II for six weeks. On day 14 of the infusion of angiotensin II or vehicle (normotensive; NT), mice were exposed either to air or WPS for four consecutive weeks. Each session was 30 min/day and 5 days/week. In NT mice, WPS increased systolic blood pressure (SBP) compared with NT air-exposed group. SBP increase was elevated in HT+WPS group versus either HT+air or NT+WPS. Similarly, the plasma levels of brain natriuretic peptide, C-reactive protein, 8-isoprostane and superoxide dismutase were increased in HT+WPS compared with either HT+air or NT+WPS. In the heart tissue, several markers of oxidative stress and inflammation were increased in HT+WPS group vs the controls. Furthermore, mitochondrial dysfunction in HT+WPS group was more affected than in the HT+air or HT+WPS groups. WPS inhalation in HT mice significantly increased cardiac DNA damage, cleaved caspase 3, expression of the autophagy proteins beclin 1 and microtubule-associated protein light chain 3B, and phosphorylated nuclear factor κ B, compared with the controls. Compared with HT+air mice, heart histology of WPS-exposed HT mice showed increased cardiomyocyte damage, neutrophilic and lymphocytic infiltration and focal fibrosis. We conclude that, in HT mice, WPS inhalation worsened hypertension, cardiac oxidative stress, inflammation, mitochondrial dysfunction, DNA damage, apoptosis and autophagy. The latter effects were associated with a mechanism involving NF-κB activation.

Solid herbal extract of Primula veris L. improves morphofunctional condition of rats’ myocardium in chronic alcohol intoxicat

Background and aim

Chronic alcohol intoxication (CAI) induces heart damage. One of the promising ways of its treatment involves the administration of herbal medicinal products. The purpose of this study was to explore the effect of solid herbal extract of Primula veris L. (PVSHE) on the morphofunctional changes in rats' myocardium after CAI.

Experimental procedure

CAI was simulated for 24 weeks. Loading testing was used to assess the functional condition of the heart, the functional assessment of mitochondria was based on the polarographic determination of oxygen consumption rate and determination of the indices of lipid peroxidation and antioxidant enzymes activity. We performed a microscopic examination of the left ventricle following the standard protocol of histological processing and h&e staining.

Results and conclusion

PVSHE restricts the toxic effects of ethanol on the heart which was indicated by a higher rise in the rates of myocardial contraction (by an average of 3.9 times, P < 0.05) and relaxation (2.6 times under volume load, P < 0.05), LVP (by an average of 1.7 times, P < 0.05) and MISP (by an average of 1.5 times, P < 0.05). PVSHE caused an improvement in the functional state of rats' cardiac mitochondria exposed to CAI, which was demonstrated by on average 1.3-1.4 times (P < 0.05) as high RCR as compared to the control group. The histological examination of the myocardium of the animals treated with PVSHE showed the increase in the volume fraction of cardiac myocytes, and a 31.2% (P < 0.05) decline in the interstitial volume. Therefore, PVSHE has a protective effect on the heart after CAI.

The role and mechanism of unfolded protein response signaling pathway in methylmercury-induced apoptosis of mouse spermatocytes germ cell-2 cells

The study aimed to explore the role and mechanism of unfolded protein response (UPR) in methylmercury (MeHg)-induced Mouse Spermatocytes (GC-2spd[ts]) apoptosis. Methods such as MTT, flow cytometry, and Western Blot were used to evaluate the cell viability, membrane potential (MMP), reactive oxygen species (ROS), calcium ion (Ca²⁺ ), rate of cell apoptosis, and the expression of apoptosis-related and UPR-related protein. The results showed that with the increase of MeHg concentration, cell viability and MMP decreased, ROS, Ca²⁺ , rate of cell apoptosis, and the expression of apoptosis-related protein and UPR-related protein increased. To further explore the effect of ROS-induced oxidative damage on it, the ROS inhibitor N-acetyl-L-cysteine (NAC) was used. The effects of MeHg on germ cell (GC-2) cells were partially inhibited after NAC pretreatment. Our present study proved that MeHg might induce cell apoptosis by activating the UPR signaling pathway in GC-2 cells and affect normal reproductive function.

Psychological and biological mechanisms linking trauma with cardiovascular disease risk

Cardiovascular disease (CVD) is the leading cause of death and disability worldwide, and experiences of psychological trauma have been associated with subsequent CVD onset. Identifying key pathways connecting trauma with CVD has the potential to inform more targeted screening and intervention efforts to offset elevated cardiovascular risk. In this narrative review, we summarize the evidence for key psychological and biological mechanisms linking experiences of trauma with CVD risk. Additionally, we describe various methodologies for measuring these mechanisms in an effort to inform future research related to potential pathways. With regard to mechanisms involving posttraumatic psychopathology, the vast majority of research on psychological distress after trauma and CVD has focused on posttraumatic stress disorder (PTSD), even though posttraumatic psychopathology can manifest in other ways as well. Substantial evidence suggests that PTSD predicts the onset of a range of cardiovascular outcomes in trauma-exposed men and women, yet more research is needed to better understand posttraumatic psychopathology more comprehensively and how it may relate to CVD. Further, dysregulation of numerous biological systems may occur after trauma and in the presence of posttraumatic psychopathology; these processes of immune system dysregulation and elevated inflammation, oxidative stress, mitochondrial dysfunction, renin-angiotensin system dysregulation, and accelerated biological aging may all contribute to subsequent cardiovascular risk, although more research on these pathways in the context of traumatic stress is needed. Given that many of these mechanisms are closely intertwined, future research using a systems biology approach may prove fruitful for elucidating how processes unfold to contribute to CVD after trauma.

Endogenous SOD2 (Superoxide Dismutase) Regulates Platelet-Dependent Thrombin Generation and Thrombosis During Aging

BACKGROUND

Reactive oxygen species (ROS) contribute to platelet hyperactivation during aging. Several oxidative pathways and antioxidant enzymes have been implicated; however, their mechanistic contributions during aging remain elusive. We hypothesized that mitochondria are an important source of platelet ROS and that mitochondrial SOD2 (superoxide dismutase) protects against mitochondrial ROS-driven platelet activation and thrombosis during aging.

METHODS

We studied littermates of platelet-specific SOD2-knockout (SOD2fl/flPf4Cre, pSOD2-KO) and control (SOD2fl/fl) mice at young (4-5 months) or old (18-20 months) ages. We examined agonist-induced platelet activation, platelet-dependent thrombin generation potential, and susceptibility to in vivo thrombosis.

RESULTS

Platelet αIIbβ3 activation, aggregation, and adhesion were increased to similar extents in aged mice of both genotypes compared with young mice. In contrast, the age-dependent increases in mitochondrial and total cellular ROS, calcium elevation, and phosphatidylserine exposure were augmented in platelets from pSOD2-KO mice compared with control mice. Aged pSOD2-KO mice showed increased platelet-dependent thrombin generation compared with aged control mice. In vivo, aged pSOD2-KO mice exhibited enhanced susceptibility to carotid artery and pulmonary thrombosis compared to aged control mice. Adoptive transfer of platelets from aged pSOD2-KO but not aged control mice increased thrombotic susceptibility in aged host mice, suggesting a prothrombotic effect of platelet pSOD2 deficiency. Treatment with avasopasem manganese (GC4419), a SOD mimetic, decreased platelet mitochondrial pro-oxidants, cellular ROS levels, and inhibited procoagulant platelet formation and arterial thrombosis in aged mice.

CONCLUSIONS

Platelet mitochondrial ROS contributes to age-related thrombosis and endogenous SOD2 protects from platelet-dependent thrombin generation and thrombosis during aging.

Early cardiac aging linked to impaired stress-resistance and transcriptional control of stress response, quality control and mitochondrial pathways

Phenotypic and transcriptomic evidence of early cardiac aging, and associated mechanisms, were investigated in young to middle-aged male mice (C57Bl/6; ages 8, 16, 32, 48 wks). Left ventricular gene expression (profiled via Illumina MouseWG-6 BeadChips), contractile and coronary function, and stress-resistance were assessed in Langendorff perfused hearts under normoxic conditions and following ischemic insult (20 min global ischemia-45 min reperfusion; I-R). Baseline or normoxic contractile function was unaltered by age, while cardiac and coronary 'reserves' (during β-adrenoceptor stimulation; 1 μM isoproterenol) declined by 48 wks. Resistance to I-R injury fell from 16 to 32 wks. Age-dependent transcriptional changes In un-stressed hearts were limited to 104 genes (>1.3-fold; 0.05 FDR), supporting: up-regulated innate defenses (glutathione and xenobiotic metabolism, chemotaxis, interleukins) and catecholamine secretion; and down-regulated extracellular matrix (ECM), growth factor and survival (PI3K/Akt) signaling. In stressed (post-ischemic) myocardium, ∼15-times as many genes (1528) were age-dependent, grouped into 6 clusters (>1.3-fold change; 0.05 FDR): most changing from 16 wks (45 % up/44 % down), a further 5 % declining from 32 wks. Major age-dependent Biological Processes in I-R hearts reveal: declining ATP metabolism, oxidative phosphorylation, cardiac contraction and morphogenesis, phospholipid metabolism and calcineurin signaling; increasing proteolysis and negative control of MAPK; and mixed changes in nuclear transport and angiogenic genes. Pathway analysis supports reductions in: autophagy, stress response, ER protein processing, mRNA surveillance and ribosome/translation genes; with later falls in mitochondrial biogenesis, oxidative phosphorylation and proteasome genes in I-R hearts. Summarizing, early cardiac aging is evident from 16 to 32 wks in male mice, characterized by: declining cardiovascular reserve and stress-resistance, transcriptomic evidence of constitutive stress and altered catecholamine and survival/growth signaling in healthy hearts; and declining stress response, quality control, mitochondrial energy metabolism and cardiac modeling processes in stressed hearts. These very early changes, potentially key substrate for advanced aging, may inform approaches to healthy aging and cardioprotection in the adult heart.

Mitochondrial Effects of Common Cardiovascular Medications: The Good, the Bad and the Mixed

Mitochondria are central organelles in the homeostasis of the cardiovascular system via the integration of several physiological processes, such as ATP generation via oxidative phosphorylation, synthesis/exchange of metabolites, calcium sequestration, reactive oxygen species (ROS) production/buffering and control of cellular survival/death. Mitochondrial impairment has been widely recognized as a central pathomechanism of almost all cardiovascular diseases, rendering these organelles important therapeutic targets. Mitochondrial dysfunction has been reported to occur in the setting of drug-induced toxicity in several tissues and organs, including the heart. Members of the drug classes currently used in the therapeutics of cardiovascular pathologies have been reported to both support and undermine mitochondrial function. For the latter case, mitochondrial toxicity is the consequence of drug interference (direct or off-target effects) with mitochondrial respiration/energy conversion, DNA replication, ROS production and detoxification, cell death signaling and mitochondrial dynamics. The present narrative review aims to summarize the beneficial and deleterious mitochondrial effects of common cardiovascular medications as described in various experimental models and identify those for which evidence for both types of effects is available in the literature.

Mitochondrial dynamics involves molecular and mechanical events in motility, fusion and fission

Mitochondria are cell organelles that play pivotal roles in maintaining cell survival, cellular metabolic homeostasis, and cell death. Mitochondria are highly dynamic entities which undergo fusion and fission, and have been shown to be very motile in vivo in neurons and in vitro in multiple cell lines. Fusion and fission are essential for maintaining mitochondrial homeostasis through control of morphology, content exchange, inheritance of mitochondria, maintenance of mitochondrial DNA, and removal of damaged mitochondria by autophagy. Mitochondrial motility occurs through mechanical and molecular mechanisms which translocate mitochondria to sites of high energy demand. Motility also plays an important role in intracellular signaling. Here, we review key features that mediate mitochondrial dynamics and explore methods to advance the study of mitochondrial motility as well as mitochondrial dynamics-related diseases and mitochondrial-targeted therapeutics.

Intravenous Versus Wetting Solution Magnesium Sulphate to Counteract Epinephrine Cardiac Adverse Events in Abdominal Liposuction: A Randomized Controlled Trial

Background

The increased frequency of liposuction has resulted in more complications being reported. Adding epinephrine to the wetting solution could induce some cardiac adverse effects, some of which may be fatal. For instance, magnesium sulfate (MgSO₄) is known for its cardioprotective effects.

Objectives

This study aimed to evaluate the efficacy of intravenous (IV) versus wetting solution containing MgSO₄ in decreasing such cardiac adverse events during abdominal liposuction.

Methods

This randomized controlled study included 129 adult cases undergoing abdominal liposuction under general anesthesia. The participants were divided into 3 groups: Group I (control group) was only subjected to the injection of the wetting fluid (1 mL 1/1000 epinephrine added to every 1000 mL of normal saline), group II was subjected to IV MgSO₄ (40 mg/kg over 1 minute) at the same time of installing the wetting solution, and group III was subjected to MgSO₄ (40 mg/kg) added to the wetting solution.

Results

Intraoperative isoflurane consumption, intraoperative heart rate (HR), mean arterial pressure (MAP), and postoperative pain scores were significantly lower in the MgSO₄ groups (groups II and III) than group I. Cardiac adverse events (sinus tachycardia and premature ventricular contractions (PVCs)) were also significantly less frequent in groups II and III compared to group I.

Conclusions

Adding MgSO₄, either through IV or subcutaneous routes, is associated with lower intraoperative HR, MAP, and postoperative pain scores and a remarkable decrease in epinephrine-induced cardiac adverse events during liposuction.

Stress-induced biological aging: A review and guide for research priorities

Exposure to chronic adverse conditions, and the resultant activation of the neurobiological response cascade, has been associated with an increased risk of early onset of age-related disease and, recently, with an older biological age. This body of research has led to the hypothesis that exposure to stressful life experiences, when occurring repeatedly or over a prolonged period, may accelerate the rate at which the body ages. The mechanisms through which chronic psychosocial stress influences distinct biological aging pathways to alter rates of aging likely involve multiple layers in the physiological-molecular network. In this review, we integrate research using animal, human, and in vitro models to begin to delineate the distinct pathways through which chronic psychosocial stress may impact biological aging, as well as the neuroendocrine mediators (i.e., norepinephrine, epinephrine, and glucocorticoids) that may drive these effects. Findings highlight key connections between stress and aging, namely cellular metabolic activity, DNA damage, telomere length, cellular senescence, and inflammatory response patterns. We conclude with a guiding framework and conceptual model that outlines the most promising biological pathways by which chronic adverse conditions could accelerate aging and point to key missing gaps in knowledge where future research could best answer these pressing questions.

The Neuroprotective Effect of Shenmai Injection on Oxidative Stress Injury in PC12 Cells Based on Network Pharmacology

Background

Shenmai injection (SMI) has been used in the treatment of cerebrovascular diseases and cardiovascular diseases. However, the underlying mechanism of SMI for neuroprotection after acute ischemic stroke (AIS) remains unclear. This study aimed to explore the potential molecular mechanism of SMI in treating reperfusion injury after AIS and its protective effect on PC12 cells against oxidative stress through in vitro experiments based on network pharmacological predictions.

Methods

The network pharmacology method was used to collect the compounds in SMI and AIS damage targets, construct the "drug-disease" target interaction network diagram, screen the core targets, and predict the potential mechanism of SMI treatment of AIS. In addition, the oxidative stress model of PC12 cells was induced by H₂O₂ to evaluate the neuroprotective effect and predictive mechanism of SMI on PC12 cells.

Results

A component-targeted disease and functional pathway network showed that 24 components from SMI regulated 77 common targets shared by SMI and AIS. In PC12 cells damaged by H₂O₂, SMI increased cell survival, alleviated oxidative stress injury, prevented cell apoptosis, and increased the expression of APJ, AMPK, and p-GSK-3β. After Si-APJ silenced APJ expression, the above protective effect of SMI was significantly weakened.

Conclusion

SMI is characterized by multiple components, multiple targets, and multiple pathways and inhibits oxidative stress and alleviates nerve injury induced by H₂O₂ through regulating the APJ/AMPK/GSK-3β pathway.

FUN14 Domain Containing 1 (FUNDC1): A Promising Mitophagy Receptor Regulating Mitochondrial Homeostasis in Cardiovascular Diseases

Mitochondria, the intracellular organelles for cellular aerobic respiration and energy production, play an important role in the regulation of cell metabolism and cell fate. Mitophagy, a selective form of autophagy, maintains dynamic homeostasis of cells through targeting long-lived or defective mitochondria for timely clearance and recycling. Dysfunction in mitophagy is involved in the molecular mechanism responsible for the onset and development of human diseases. FUN14 domain containing 1 (FUNDC1) is a mitochondrial receptor located in the outer mitochondria membrane (OMM) to govern mitophagy process. Emerging evidence has demonstrated that levels and phosphorylation states of FUNDC1 are closely related to the occurrence, progression and prognosis of cardiovascular diseases, indicating a novel role for this mitophagy receptor in the regulation of mitochondrial homeostasis in cardiovascular system. Here we review mitophagy mediated by FUNDC1 in mitochondria and its role in various forms of cardiovascular diseases.

Foam Cells in Atherosclerosis: Novel Insights Into Its Origins, Consequences, and Molecular Mechanisms

Foam cells play a vital role in the initiation and development of atherosclerosis. This review aims to summarize the novel insights into the origins, consequences, and molecular mechanisms of foam cells in atherosclerotic plaques. Foam cells are originated from monocytes as well as from vascular smooth muscle cells (VSMC), stem/progenitor cells, and endothelium cells. Novel technologies including lineage tracing and single-cell RNA sequencing (scRNA-seq) have revolutionized our understanding of subtypes of monocyte- and VSMC-derived foam cells. By using scRNA-seq, three main clusters including resident-like, inflammatory, and triggering receptor expressed on myeloid cells-2 (Trem2 ^hi ) are identified as the major subtypes of monocyte-derived foam cells in atherosclerotic plaques. Foam cells undergo diverse pathways of programmed cell death including apoptosis, autophagy, necroptosis, and pyroptosis, contributing to the necrotic cores of atherosclerotic plaques. The formation of foam cells is affected by cholesterol uptake, efflux, and esterification. Novel mechanisms including nuclear receptors, non-coding RNAs, and gut microbiota have been discovered and investigated. Although the heterogeneity of monocytes and the complexity of non-coding RNAs make obstacles for targeting foam cells, further in-depth research and therapeutic exploration are needed for the better management of atherosclerosis.

Common Shared Pathogenic Aspects of Small Vessels in Heart and Brain Disease

Small-vessel disease (SVD), also known as microvascular endothelial dysfunction, is a disorder with negative consequences for various organs such as the heart and brain. Impaired dilatation and constriction of small vessels in the heart lead to reduced blood flow and ischemia independently of coronary artery disease (CAD) and are associated with major cardiac events. SVD is usually a silent form of subcortical vascular burden in the brain with various clinical manifestations, such as silent-lacunar-ischemic events and confluent white-matter hyperintensities. Imaging techniques are the main help for clinicians to diagnose cardiac and brain SVD correctly. Markers of inflammation, such as C-reactive protein, tumor-necrosis-factor α, and interleukin 6, provide insight into the disease and markers that negatively influence nitric-oxide bioavailability and promote oxidative stress. Unfortunately, the therapeutic approach against SVD is still not well-defined. In the last decades, various antioxidants, oxidative stress inhibitors, and superoxide scavengers have been the target of extensive investigations due to their potential therapeutic effect, but with unsatisfactory results. In clinical practice, traditional anti-ischemic and risk-reduction therapies for CAD are currently in use for SVD treatment.

Nicotinamide mononucleotide alleviates heat stress-induced oxidative stress and apoptosis in BMECs through reducing mitochondrial damage and endoplasmic reticulum stress

Heat stress is directly correlated to mammary gland dysfunction in dairy cows, especially in summer. Abnormally high environmental temperature induces oxidative stress and apoptosis in bovine mammary epithelial cells (BMECs). Nicotinamide mononucleotide (NMN) has beneficial effects in maintaining the cellular physiological functions. In this study, we evaluate the protective effect of NMN on heat stress-induced apoptosis of BMECs and explore the potential underlying mechanisms. Our results showed that heat stress considerably decreased cell viability in BMECs, whereas pretreatment of BMECs with NMN (150 μM) for 24 h significantly alleviated the negative effects of heat stress on cells. NMN protected BMECs from heat stress-induced oxidative stress by inhibiting the excessive accumulation of reactive oxygen species (ROS) and increasing the activity of antioxidant enzymes. It also inhibited apoptosis by reducing the ratio of Bax/Bcl2 and blocking proteolytic the cleavage of Caspase-3 in heat stressed-BMECs. Importantly, NMN treatment could reduce mitochondrial damage through mediating the expression of mitochondrial fission and fusion-related genes, including Dynamin related protein 1 (Drp1), Mitochondrial fission 1 protein (Fis1), and Mitofusin1, 2 (MFN1, 2); and suppress endoplasmic reticulum stress through unfolded protein response regulator Glucose regulated protein 78 (GRP78), and downstream elements Recombinant activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP). Above all, our results demonstrate that NMN supplemention attenuates heat stress-induced oxidative stress and apoptosis in BMECs by maintaining mitochondrial fission and fusion, and regulating endoplasmic reticulum stress, which provides the convincing evidence that NMN has valuable potential in alleviating mammary gland injury of dairy cows caused by environmental heat stress.

Alternative autophagy: mechanisms and roles in different diseases

As an important mechanism to maintain cellular homeostasis, autophagy exerts critical functions via degrading misfolded proteins and damaged organelles. Recent years, alternative autophagy, a new type of autophagy has been revealed, which shares similar morphology with canonical autophagy but is independent of Atg5/Atg7. Investigations on different diseases showed the pivotal role of alternative autophagy during their physio-pathological processes, including heart diseases, neurodegenerative diseases, oncogenesis, inflammatory bowel disease (IBD), and bacterial infection. However, the studies are limited and the precise roles and mechanisms of alternative autophagy are far from clear. It is necessary to review current research on alternative autophagy and get some hint in order to provide new insight for further study. Video Abstract.

Signal Transduction during Metabolic and Inflammatory Reprogramming in Pulmonary Vascular Remodeling

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by (mal)adaptive remodeling of the pulmonary vasculature, which is associated with inflammation, fibrosis, thrombosis, and neovascularization. Vascular remodeling in PAH is associated with cellular metabolic and inflammatory reprogramming that induce profound endothelial and smooth muscle cell phenotypic changes. Multiple signaling pathways and regulatory loops act on metabolic and inflammatory mediators which influence cellular behavior and trigger pulmonary vascular remodeling in vivo. This review discusses the role of bioenergetic and inflammatory impairments in PAH development.

Mitochondrial DNA Depletion Syndrome and Its Associated Cardiac Disease

Mitochondria is a ubiquitous, energy-supplying (ATP-based) organelle found in nearly all eukaryotes. It acts as a “power plant” by producing ATP through oxidative phosphorylation, providing energy for the cell. The bioenergetic functions of mitochondria are regulated by nuclear genes (nDNA). Mitochondrial DNA (mtDNA) and respiratory enzymes lose normal structure and function when nuclear genes encoding the related mitochondrial factors are impaired, resulting in deficiency in energy production. Massive generation of reactive oxygen species and calcium overload are common causes of mitochondrial diseases. The mitochondrial depletion syndrome (MDS) is associated with the mutations of mitochondrial genes in the nucleus. It is a heterogeneous group of progressive disorders characterized by the low mtDNA copy number. TK2, FBXL4, TYPM, and AGK are genes known to be related to MDS. More recent studies identified new mutation loci associated with this disease. Herein, we first summarize the structure and function of mitochondria, and then discuss the characteristics of various types of MDS and its association with cardiac diseases.

The regulatory mechanism between lysosomes and mitochondria in the aetiology of cardiovascular diseases

Coordinated action among various organelles maintains cellular functions. For instance, mitochondria and lysosomes are the main organelles contributing to cellular metabolism and provide energy for cardiomyocyte contraction. They also provide essential signalling platforms in the cell that regulate many key processes such as autophagy, apoptosis, oxidative stress, inflammation and cell death. Often, abnormalities in mitochondrial or lysosomal structures and functions bring about cardiovascular diseases (CVDs). Although the communication between mitochondria and lysosomes throughout the cardiovascular system is intensely studied, the regulatory mechanisms have not been completely understood. Thus, we summarize the most recent studies related to mitochondria and lysosomes' role in CVDs and their potential connections and communications under cardiac pathophysiological conditions. Further, we discuss limitations and future perspectives regarding diagnosis, therapeutic strategies and drug discovery in CVDs.

Aging-Induced Impairment of Vascular Function: Mitochondrial Redox Contributions and Physiological/Clinical Implications

Significance: The vasculature responds to the respiratory needs of tissue by modulating luminal diameter through smooth muscle constriction or relaxation. Coronary perfusion, diastolic function, and coronary flow reserve are drastically reduced with aging. This loss of blood flow contributes to and exacerbates pathological processes such as angina pectoris, atherosclerosis, and coronary artery and microvascular disease. Recent Advances: Increased attention has recently been given to defining mechanisms behind aging-mediated loss of vascular function and development of therapeutic strategies to restore youthful vascular responsiveness. The ultimate goal aims at providing new avenues for symptom management, reversal of tissue damage, and preventing or delaying of aging-induced vascular damage and dysfunction in the first place. Critical Issues: Our major objective is to describe how aging-associated mitochondrial dysfunction contributes to endothelial and smooth muscle dysfunction via dysregulated reactive oxygen species production, the clinical impact of this phenomenon, and to discuss emerging therapeutic strategies. Pathological changes in regulation of mitochondrial oxidative and nitrosative balance (Section 1) and mitochondrial dynamics of fission/fusion (Section 2) have widespread effects on the mechanisms underlying the ability of the vasculature to relax, leading to hyperconstriction with aging. We will focus on flow-mediated dilation, endothelial hyperpolarizing factors (Sections 3 and 4), and adrenergic receptors (Section 5), as outlined in Figure 1. The clinical implications of these changes on major adverse cardiac events and mortality are described (Section 6). Future Directions: We discuss antioxidative therapeutic strategies currently in development to restore mitochondrial redox homeostasis and subsequently vascular function and evaluate their potential clinical impact (Section 7). Antioxid. Redox Signal. 35, 974-1015.

Instability in NAD+ metabolism leads to impaired cardiac mitochondrial function and communication

Poly(ADP-ribose) polymerase (PARP) enzymes initiate (mt)DNA repair mechanisms and use nicotinamide adenine dinucleotide (NAD⁺) as energy source. Prolonged PARP activity can drain cellular NAD⁺ reserves, leading to de-regulation of important molecular processes. Here, we provide evidence of a pathophysiological mechanism that connects mtDNA damage to cardiac dysfunction via reduced NAD⁺ levels and loss of mitochondrial function and communication. Using a transgenic model, we demonstrate that high levels of mice cardiomyocyte mtDNA damage cause a reduction in NAD⁺ levels due to extreme DNA repair activity, causing impaired activation of NAD⁺-dependent SIRT3. In addition, we show that myocardial mtDNA damage in combination with high dosages of nicotinamideriboside (NR) causes an inhibition of sirtuin activity due to accumulation of nicotinamide (NAM), in addition to irregular cardiac mitochondrial morphology. Consequently, high doses of NR should be used with caution, especially when cardiomyopathic symptoms are caused by mitochondrial dysfunction and instability of mtDNA.

Deubiquitinating enzyme USP30 negatively regulates mitophagy and accelerates myocardial cell senescence through antagonism of Parkin

Cell senescence is associated with age-related pathological changes. Increasing evidence has revealed that mitophagy can selectively remove dysfunctional mitochondria. Overexpression of ubiquitin-specific protease 30 (USP30) has been documented to influence mitophagy and deubiquitination of mitochondrial Parkin substrates. This study was conducted to evaluate the roles of USP30 and Parkin in myocardial cell senescence and mitophagy. Initially, myocardial cells were isolated from neonatal SD rats and subjected to d-gal treatment to induce cell senescence, after which the effects of d-gal on mitochondria damage, ROS production, cell senescence, and mitophagy were assessed. The myocardial cells were infected with lentiviruses bearing overexpression plasmids or shRNA targeting Parkin or USP30 to elucidate the effects of Parkin and USP30 on d-gal-induced mitophagy damage and cell senescence. Finally, aging was induced in rats by subcutaneous injection of d-gal to determine the role of Parkin and USP30 on cell senescence in vivo. d-gal was found to trigger mitochondria damage, ROS production, and cell senescence in myocardial cells. The overexpression of Parkin or silencing of USP30 reduced d-gal-induced mitochondrial damage and relieved d-gal-induced myocardial cell senescence. Moreover, the in vivo experiments validated that either elevation of Parkin or silencing USP30 could alleviate d-gal-induced myocardial cell senescence in rats. Silencing USP30 alleviates d-gal-induced mitochondrial damage and consequently suppresses myocardial cell senescence by activating Parkin. Our study highlights the potential of USP30 as a novel target against myocardial cell senescence.

Cardiovascular Health and Mitochondrial Function: Testing an Association

BACKGROUND

Although mitochondrial dysfunction appears to be a contributing factor in the pathogenesis of cardiovascular and metabolic diseases, empirical data on this association are still lacking. This study evaluated whether mitochondrial oxidative capacity, as assessed by phosphorus magnetic resonance spectroscopy, was associated with cardiovascular risk, as estimated by the Framingham Risk Score (FRS), and with a clinical history of cardiovascular disease (CVD), in community-dwelling adults.

METHOD

A total of 616 subjects from the Baltimore Longitudinal Study of Aging (mean age 66 years) underwent a comprehensive clinical evaluation. Mitochondrial oxidative capacity in skeletal muscle was assessed as post-exercise phosphocreatine recovery time constant by phosphorus magnetic resonance spectroscopy. Multivariate regression models were employed to determine the cross-sectional association of mitochondrial oxidative capacity with FRS and history of CVD.

RESULTS

Decreased mitochondrial oxidative capacity was strongly associated with higher FRS independent of age, body composition, and physical activity. Lower oxidative capacity was also associated with a history of positive of CVD and higher number of CVD events.

CONCLUSIONS

We speculate that the observed association could reflect the effect of an excessive production of oxidative species by dysfunctional mitochondria. Furthermore, decreased energy production could hamper the functionality of heart and vessels. In turn, a malfunctioning cardiovascular apparatus could fail to deliver the oxygen necessary for optimal mitochondrial energy production, therefore creating a vicious cycle. Longitudinal studies are necessary to ascertain the directionality of the association and the eventual presence of common pathogenetic roots. In conclusion, mitochondria could represent an important target for intervention in cardiovascular health.

Autophagy-Related Genes in Atherosclerosis

Background

Atherosclerosis (AS) is a common chronic vascular inflammatory disease and one of the main causes of cardiovascular/cerebrovascular diseases (CVDs). Autophagy-related genes (ARGs) play a crucial part in pathophysiological processes of AS. However, the expression profile of ARGs has rarely been adopted to explore the relationship between autophagy and AS. Therefore, using the expression profile of ARGs to explore the relationship between autophagy and AS may provide new insights for the treatment of CVDs.

Methods

The differentially expressed ARGs of the GSE57691 dataset were obtained from the Human Autophagy Database (HADb) and the Gene Expression Omnibus (GEO) database, and the GSE57691 dataset contains 9 aortic atheroma tissues and 10 normal aortic tissues. The differentially expressed ARGs of the GSE57691 dataset were analyzed by protein-protein interaction (PPI), gene ontology analysis (GO), and Kyoto Encyclopedia of Genes and Genomes analysis (KEGG) and were chosen to explore related miRNAs/transcriptional factors.

Results

The GSE57691 dataset had a total of 41 differentially expressed ARGs. The GO analysis results revealed that ARGs were mainly enriched in autophagy, autophagosome, and protein serine/threonine kinase activity. KEGG analysis results showed that ARGs were mainly enriched in autophagy-animal and longevity regulating signaling pathways. Expressions of ATG5, MAP1LC3B, MAPK3, MAPK8, and RB1CC1 were regarded as focus in the PPI regulatory networks. Furthermore, 11 related miRNAs and 6 related transcription factors were obtained by miRNAs/transcription factor target network analysis.

Conclusions

Autophagy and ARGs may play a vital role in regulating the pathophysiology of AS.

Anakinra Activates Superoxide Dismutase 2 to Mitigate Inflammasome Activity

Inflammasomes are powerful cytosolic sensors of environmental stressors and are critical for triggering interleukin-1 (IL-1)-mediated inflammatory responses. However, dysregulation of inflammasome activation may lead to pathological conditions, and the identification of negative regulators for therapeutic purposes is increasingly being recognized. Anakinra, the recombinant form of the IL-1 receptor antagonist, proved effective by preventing the binding of IL-1 to its receptor, IL-1R1, thus restoring autophagy and dampening NLR family pyrin domain containing 3 (NLRP3) activity. As the generation of mitochondrial reactive oxidative species (ROS) is a critical upstream event in the activation of NLRP3, we investigated whether anakinra would regulate mitochondrial ROS production. By profiling the activation of transcription factors induced in murine alveolar macrophages, we found a mitochondrial antioxidative pathway induced by anakinra involving the manganese-dependent superoxide dismutase (MnSOD) or SOD2. Molecularly, anakinra promotes the binding of SOD2 with the deubiquitinase Ubiquitin Specific Peptidase 36 (USP36) and Constitutive photomorphogenesis 9 (COP9) signalosome, thus increasing SOD2 protein longevity. Functionally, anakinra and SOD2 protects mice from pulmonary oxidative inflammation and infection. On a preclinical level, anakinra upregulates SOD2 in murine models of chronic granulomatous disease (CGD) and cystic fibrosis (CF). These data suggest that protection from mitochondrial oxidative stress may represent an additional mechanism underlying the clinical benefit of anakinra and identifies SOD2 as a potential therapeutic target.

Phenolic acid metabolites of polyphenols act as inductors for hormesis in C. elegans

INTRODUCTION

Aging represents a major risk factors for metabolic diseases, such as diabetes, obesity, or neurodegeneration. Polyphenols and their metabolites, especially simple phenolic acids, gained growing attention as a preventive strategy against age-related, non-communicable diseases, due to their hormetic potential. Using Caenorhabditis elegans (C. elegans) we investigate the effect of protocatechuic, gallic, and vanillic acid on mitochondrial function, health parameters, and the induction of potential hormetic pathways.

METHODS

Lifespan, heat-stress resistance and chemotaxis of C. elegans strain P X 627, a specific model for aging, were assessed in 2-day and 10-day old nematodes. Mitochondrial membrane potential (ΔΨm) and ATP generation were measured. mRNA expression levels of longevity and energy metabolism-related genes were determined using qRT-PCR.

RESULTS

All phenolic acids were able to significantly increase the nematodes lifespan, heat-stress resistance and chemotaxis at micromolar concentrations. While ΔΨm was only affected by age, vanillic acid (VA) significantly decreased ATP concentrations in aged nematodes. Longevity pathways, were activated by all phenolic acids, while VA also induced glycolytic activity and response to cold.

CONCLUSION

While life- and health span parameters are positively affected by the investigated phenolic acids, the concentrations applied were unable to affect mitochondrial performance. Therefore we suggest a hormetic mode of action, especially by activation of the sirtuin-pathway.

Cardiac-specific overexpression of miR-122 induces mitochondria-dependent cardiomyocyte apoptosis and promotes heart failure by inhibiting Hand2

MicroRNA‐122 (miR‐122) is one of several microRNAs elevated in heart failure patients. To investigate the potential role and mechanism of miR‐122 in heart failure, we constructed a transgenic mouse overexpressing miR‐122 in the heart. This mouse exhibited cardiac dysfunction (as assessed by transthoracic echocardiography), morphological abnormalities of the heart and cardiomyocyte apoptosis characteristic of heart failure. Mechanistically, we identified the Hand2 transcription factor as a direct target of miR‐122 using a dual‐luciferase reporter assay. In Tg‐miR‐122 mice and H9C2 cells with miR‐122 mimics, we detected apoptosis and increased expression of dynamin‐related protein‐1 (Drp1). This effect was blocked with prior knockdown of Hand2 in vitro. Our work suggests that miR‐122 causes cardiomyocyte apoptosis by inhibiting Hand2 and consequently increasing Drp1‐mediated mitochondrial fission. Such a mechanism likely contributes to heart failure and so modulating this pathway could be therapeutically valuable against heart failure.

Silica nanoparticles induce mitochondrial pathway-dependent apoptosis by activating unfolded protein response in human neuroblastoma cells

The application of silica nanoparticles (SiNPs) in areas of agriculture and medicine has raised great concerns for the potential adverse effects of SiNPs. The increasing toxicological studies focused mainly on the lung and cardiovascular system, but the adverse effects of SiNPs on nervous system have not been well explored. This study aimed to evaluate the role and mechanism of unfolded protein reaction (UPR) in SiNPs-induced cell injury on nerve cells in vitro. We investigated the UPR-mediated apoptosis caused by SiNPs in human neuroblastoma (SH-SY5Y) cell line. The size of SiNPs and its effect on cell ultrastructure were observed by transmission electron microscopy (TEM). Cell growth, mitochondrial membrane potential (MMP), calcium ion (Ca²⁺ ), apoptosis rate, and the expression level of related proteins were evaluated using MTT, flow cytometry, and western blot in SH-SY5Y cells exposed to SiNPs. The results showed that with the increase of SiNPs concentration, cell viability decreased, MMP decreased, active oxygen (ROS), and Ca²⁺ levels increased in a dose-dependent manner. In addition, protein expression of PERK, GRP78, and other related proteins in the unfolded protein response increased in a dose-response manner together with the expression of apoptosis proteins. Conclusively, this study confirmed that SiNPs can affect the neural system by interfering structure and functional and inducing apoptosis in nerve cells through unfolded protein response.

Metformin protects cardiomyocytes against oxygen-glucose deprivation injury by promoting autophagic flux through AMPK pathway

Metformin has been shown to protect myocardial ischaemia/reperfusion or hypoxia/reoxygenation injury. In our current study, we investigated the effects of metformin on autophagy and its possible underlying mechanisms in in vivo myocardial infarction (MI) model and in vitro oxygen-glucose deprivation (OGD) model. A rat model of MI was made by ligating coronary artery in vivo study. Metformin (200 mg/kg/day) could improve cardiac function, prevent rats from MI-induced injury by reducing myocardial infarct size and apoptosis. Moreover, metformin furtherly promoted autophagy by increasing the protein expression of LC3-II, ATG5, ATG7 and Beclin1, and by involving AMPK pathway during MI. H9c2 cells were treated with metformin (4 mM) in vitro study to assess its effects after exposure to OGD. Metformin increased cell viability and inhibited OGD-induced LDH synthesis and cell apoptosis. Furthermore, metformin increased autophagosome formations as well as expression of autophagy-related proteins, promoted autophagic flux. In addition, metformin augmented the protein level of Bcl-2 and diminished the protein levels of Bax and cleaved caspase-3. Metformin also upregulated p-AMPK expression. Nevertheless, the above-mentioned effects of metformin on H9c2 cells were remarkably eliminated by compound C (an AMPK inhibitor). In summary, we displayed that metformin protected cardiomyocytes against OGD-induced injury and apoptosis by promoting autophagic flux through the AMPK pathway.

Beneficial Effects of a Mixture of Algae and Extra Virgin Olive Oils on the Age-Induced Alterations of Rodent Skeletal Muscle: Role of HDAC-4

Aging is associated with a progressive decline in skeletal muscle mass, strength and function (sarcopenia). We have investigated whether a mixture of algae oil (25%) and extra virgin olive oil (75%) could exert beneficial effects on sarcopenia. Young (3 months) and old (24 months) male Wistar rats were treated with vehicle or with the oil mixture (OM) (2.5 mL/kg) for 21 days. Aging decreased gastrocnemius weight, total protein, and myosin heavy chain mRNA. Treatment with the OM prevented these effects. Concomitantly, OM administration decreased the inflammatory state in muscle; it prevented the increase of pro-inflammatory interleukin-6 (IL-6) and the decrease in anti-inflammatory interleukin-10 (IL-10) in aged rats. The OM was not able to prevent aging-induced alterations in either the insulin-like growth factor I/protein kinase B (IGF-I/Akt) pathway or in the increased expression of atrogenes in the gastrocnemius. However, the OM prevented decreased autophagy activity (ratio protein 1A/1B-light chain 3 (LC3b) II/I) induced by aging and increased expression of factors related with muscle senescence such as histone deacetylase 4 (HDAC-4), myogenin, and IGF-I binding protein 5 (IGFBP-5). These data suggest that the beneficial effects of the OM on muscle can be secondary to its anti-inflammatory effect and to the normalization of HDAC-4 and myogenin levels, making this treatment an alternative therapeutic tool for sarcopenia.

BCL2 Interacting Protein 3-like/NIX-mediated Mitophagy Plays an Important Role in the Process of Age-related Hearing Loss

Clearance of dysfunctional mitochondria via mitophagy is essential for cell survival and cochlear functions. However, it is not clear which genes are significantly involved in this process. Here, we investigated the changes in mitophagy and mitophagy-associated genes in mouse auditory cells to determine a possible correlation between mitophagy and age-related hearing loss (ARHL). Here, we show that most transcripts associated with mitophagy were downregulated in an age-dependent manner. We identified one significant differentially expressed gene associated with mitophagy, BCL2 interacting protein 3-like (BNIP3L)/NIX. Mitophagy-inhibited cells with BNIP3L/NIX knockdown showed hyperresponsiveness to oxidative stress resulting in cell senescence with increased levels of TOMM20 and LC3B. Overexpression of BNIP3L/NIX promotes the degradation of TOMM20 and LC3B during premature cell senescence. In conclusion, BNIP3L/NIX may play an important role in mitochondria degradation maintaining cochlear cell homeostasis during the aging process of hearing.

Mitochondria as a therapeutic target for cardiac ischemia‑reperfusion injury (Review)

Acute myocardial infarction is the leading cause of cardiovascular-related mortality and chronic heart failure worldwide. As regards treatment, the reperfusion of ischemic tissue generates irreversible damage to the myocardium, which is termed 'cardiac ischemia-reperfusion (IR) injury'. Due to the large number of mitochondria in cardiomyocytes, an increasing number of studies have focused on the roles of mitochondria in IR injury. The primary causes of IR injury are reduced oxidative phosphorylation during hypoxia and the increased production of reactive oxygen species (ROS), together with the insufficient elimination of these oxidative species following reperfusion. IR injury includes the oxidation of DNA, incorrect modifications of proteins, the disruption of the mitochondrial membrane and respiratory chain, the loss of mitochondrial membrane potential (∆Ψm), Ca²⁺ over-load, mitochondrial permeability transition pore formation, swelling of the mitochondria, and ultimately, cardiomyocyte necrosis. The present review article discusses the molecular mechanisms of IR injury, and summarizes the metabolic and dynamic changes occurring in the mitochondria in response to IR stress. The mitochondria are strongly recommended as a target for the development of therapeutic agents; however, the appropriate use of agents remains a challenge.

An impedimetric assay for the identification of abnormal mitochondrial dynamics in living cells

Mitochondrial dynamics (fission and fusion) plays an important role in cell functions. Disruption in mitochondrial dynamics has been associated with diseases such as neurobiological disorders and cardiovascular diseases. Analysis of mitochondrial fission/fusion has been mostly achieved through direct visualization of the fission/fusion events in live-cell imaging of fluorescently labeled mitochondria. In this study, we demonstrated a label-free, non-invasive Electrical Impedance Spectroscopy (EIS) approach to analyze mitochondrial dynamics in a genetically modified human neuroblastoma SH-SY5Y cell line with no huntingtin protein expression. Huntingtin protein has been shown to regulate mitochondria dynamics. We performed EIS studies on normal SH-SY5Y cells and two independent clones of huntingtin-null cells. The impedance data was used to determine the suspension conductivity and further cytoplasmic conductivity and relate to the abnormal mitochondrial dynamics. For instance, the cytoplasm conductivity value was increased by 11% from huntingtin-null cells to normal cells. Results of this study demonstrated that EIS is sensitive to characterize the abnormal mitochondrial dynamics that can be difficult to quantify by the conventional microscopic method.

Coenzyme Q10: Novel Formulations and Medical Trends

The aim of this review is to shed light over the most recent advances in Coenzyme Q10 (CoQ10) applications as well as to provide detailed information about the functions of this versatile molecule, which have proven to be of great interest in the medical field. Traditionally, CoQ10 clinical use was based on its antioxidant properties; however, a wide range of highly interesting alternative functions have recently been discovered. In this line, CoQ10 has shown pain-alleviating properties in fibromyalgia patients, a membrane-stabilizing function, immune system enhancing ability, or a fundamental role for insulin sensitivity, apart from potentially beneficial properties for familial hypercholesterolemia patients. In brief, it shows a remarkable amount of functions in addition to those yet to be discovered. Despite its multiple therapeutic applications, CoQ10 is not commonly prescribed as a drug because of its low oral bioavailability, which compromises its efficacy. Hence, several formulations have been developed to face such inconvenience. These were initially designed as lipid nanoparticles for CoQ10 encapsulation and distribution through biological membranes and eventually evolved towards chemical modifications of the molecule to decrease its hydrophobicity. Some of the most promising formulations will also be discussed in this review.

Non-hematopoietic erythropoietin-derived peptides for atheroprotection and treatment of cardiovascular diseases

Relevance: Cardiovascular diseases continue to be the leading cause of premature adult death.

Lipid profile and atherogenesis: Dislipidaemia leads to subsequent lipid accumulation and migration of immunocompetent cells into the vessel intima. Macrophages accumulate cholesterol forming foam cells – the morphological substrate of atherosclerosis in its initial stage.

Inflammation and atherogenesis: Pro-inflammatory factors provoke oxidative stress, vascular wall damage and foam cells formation.

Endothelial and mitochondrial dysfunction in the development of atherosclerosis: Endothelial mitochondria are some of the organelles most sensitive to oxidative stress. Damaged mitochondria produce excess superoxide and H2O2, which are the main factors of intracellular damage, further increasing endothelial dysfunction.

Short non-hematopoietic erythropoietin-based peptides as innovative atheroprotectors: Research in recent decades has shown that erythropoietin has a high cytoprotective activity, which is mainly associated with exposure to the mitochondrial link and has been confirmed in various experimental models. There is also a short-chain derivative, the 11-amino acid pyroglutamate helix B surface peptide (PHBSP), which selectively binds to the erythropoietin heterodymic receptor and reproduces its cytoprotective properties. This indicates the promising use of short-chain derivatives of erythropoietin for the treatment and prevention of atherosclerotic vascular injury. In the future, it is planned to study the PHBSP derivatives, the modification of which consists in adding RGD and PGP tripeptides with antiaggregant properties to the original 11-member peptide.

Targeting mitochondrial fitness as a strategy for healthy vascular aging

Cardiovascular diseases (CVD) are the leading cause of death worldwide and aging is the primary risk factor for CVD. The development of vascular dysfunction, including endothelial dysfunction and stiffening of the large elastic arteries (i.e., the aorta and carotid arteries), contribute importantly to the age-related increase in CVD risk. Vascular aging is driven in large part by oxidative stress, which reduces bioavailability of nitric oxide and promotes alterations in the extracellular matrix. A key upstream driver of vascular oxidative stress is age-associated mitochondrial dysfunction. This review will focus on vascular mitochondria, mitochondrial dysregulation and mitochondrial reactive oxygen species (ROS) production and discuss current evidence for prevention and treatment of vascular aging via lifestyle and pharmacological strategies that improve mitochondrial health. We will also identify promising areas and important considerations ('research gaps') for future investigation.