Catechinic acid, a natural polyphenol compound, extends the lifespan of Caenorhabditis elegans via mitophagy pathways

EGCG Alleviates the Aging Toxicity Induced by 3-MCPD via IIS Pathway in Caenorhabditis elegans with Abnormal Reproduction and Heat Shock Protein

This study aimed to investigate the mitigation effect of epigallocatechin gallate (EGCG) on aging induced by 3-monochloropropane-1,2-diol (3-MCPD) in Caenorhabditis elegans, evaluate health indicators during the process, and reveal the underlying mechanism through transcriptomics and identification of mutants. The results showed that EGCG alleviated the declined fertility, shortened lifespan, reduced body size, weakened movement, increased reactive oxygen species and lipofuscin, and damaged antioxidative stress response and excessive heat shock proteins caused by 3-MCPD. Transcriptomics study indicated that treatment with 3-MCPD and EGCG altered gene expression, and gene mutants confirmed the involvement of insulin/IGF-1 signaling pathway in mediating the process that EGCG alleviated the aging toxicity induced by 3-MCPD. The study showed that EGCG alleviated the aging toxicity induced by 3-MCPD.

SKN-1 is indispensable for protection against Aβ-induced proteotoxicity by a selenopeptide derived from Cordyceps militaris

Oxidative stress (OS) and disruption of proteostasis caused by aggregated proteins are the primary causes of cell death in various diseases. Selenopeptides have shown the potential to control OS and alleviate inflammatory damage, suggesting promising therapeutic applications. However, their potential function in inhibiting proteotoxicity is not yet fully understood. To address this gap in knowledge, this study aimed to investigate the effects and underlying mechanisms of the selenopeptide VPRKL(Se)M on amyloid β protein (Aβ) toxicity in transgenic Caenorhabditis elegans. The results revealed that supplementation with VPRKL(Se)M can alleviate Aβ-induced toxic effects in the transgenic C. elegans model. Moreover, the addition of VPRKL(Se)M inhibited the Aβ aggregates formation, reduced the reactive oxygen species (ROS) levels, and ameliorated the overall proteostasis. Importantly, we found that the inhibitory effects of VPRKL(Se)M on Aβ toxicity and activation of the unfolded protein are dependent on skinhead-1 (SKN-1). These findings suggested that VPRKL(Se)M is a potential bioactive agent for modulating SKN-1, which subsequently improves proteostasis and reduces OS. Collectively, the findings from the current study suggests VPRKL(Se)M may play a critical role in preventing protein disorder and related diseases.

Mitophagy-promoting agents and their ability to promote healthy-aging

The removal of damaged mitochondrial components through a process called mitochondrial autophagy (mitophagy) is essential for the proper function of the mitochondrial network. Hence, mitophagy is vital for the health of all aerobic animals, including humans. Unfortunately, mitophagy declines with age. Many age-associated diseases, including Alzheimer's and Parkinson's, are characterized by the accumulation of damaged mitochondria and oxidative damage. Therefore, activating the mitophagy process with small molecules is an emerging strategy for treating multiple aging diseases. Recent studies have identified natural and synthetic compounds that promote mitophagy and lifespan. This article aims to summarize the existing knowledge about these substances. For readers' convenience, the knowledge is presented in a table that indicates the chemical data of each substance and its effect on lifespan. The impact on healthspan and the molecular mechanism is reported if known. The article explores the potential of utilizing a combination of mitophagy-inducing drugs within a therapeutic framework and addresses the associated challenges of this strategy. Finally, we discuss the process that balances mitophagy, i.e. mitochondrial biogenesis. In this process, new mitochondrial components are generated to replace the ones cleared by mitophagy. Furthermore, some mitophagy-inducing substances activate biogenesis (e.g. resveratrol and metformin). Finally, we discuss the possibility of combining mitophagy and biogenesis enhancers for future treatment. In conclusion, this article provides an up-to-date source of information about natural and synthetic substances that activate mitophagy and, hopefully, stimulates new hypotheses and studies that promote healthy human aging worldwide.

Epigallocatechin-3-Gallate Reduces Cd-Induced Developmental Toxicity of Bodysize in Caenorhabditis elegans via the PEK-1/eIF-2α/ATF-4 Pathway

Cadmium (Cd), a harmful heavy metal that has no biological purpose, can harm healthy fetal and child development. Epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in tea, has been shown to increase cell viability under Cd exposure and ameliorate Cd-induced kidney injury in adult male rats. Using the Caenorhabditis elegans (C. elegans) model, we demonstrated that EGCG mitigated Cd-induced body size developmental toxicity through a mechanism that did not involve chelation with EGCG and was not associated with Cd accumulation and efflux. Our research indicated that the beneficial effects of EGCG on Cd-induced body size developmental toxicity were associated with the mitigation of endoplasmic reticulum stress. Furthermore, our observations indicate that EGCG reduced Cd-induced developmental toxicity in C. elegans via the PEK-1/eIF-2α/ATF-4 pathway. Our results provide important evidence for the potential benefits of consuming tea as a detoxification agent.

Novel control strategies for the endocrine-disrupting effect of PAEs to pregnant women in traffic system

Traffic-related air pollution has become a global issue, and scientific regulation measures are urgently needed to reduce traffic pollution. Phthalates (PAEs) have been widely detected in the traffic environment; thus, they were chosen as target pollutants because of their endocrine-disrupting effects. The pathways of action and mechanisms of PAEs' endocrine-disrupting effects in pregnant women through inhalation were deduced. A novel whole-process 1C + 3D + 5R regulation system was developed to control the endocrine-disrupting effect of PAEs on pregnant women based on the cleaning production concept. (1) For source reduction, the 2D-QSAR model of endocrine-disrupting effects of PAEs in pregnant women was constructed to screen out the key influencing factors as hydrogen bond interaction and hydrophobic interaction. Based on this, a designed PAE substitute molecule with low volatility and endocrine-disrupting effects and no developmental toxicity was screened. The substitute molecule could reduce the volatilization amount of PAEs at the source by 41.76 %; (2) For process interception, selecting C-band UV light to eliminate PAEs molecules in the traffic environment can slow down 19.99 % of the endocrine-disrupting effect of PAEs molecules. The homology modeling method was used to design four kinds of green belt plant proteins with high PAEs absorption efficiency to absorb PAEs molecules in the traffic environment. Compared with the original green belt plant proteins, the absorption amount of PAEs increased by up to 96.08 %, and (3) For terminal prevention, dietary food schemes were designed to regulate PAEs' endocrine-disrupting effect on pregnant women. The optimal dietary food scheme was the simultaneous intake of glutamate, catechin and folic acid, which could reduce the adverse effect of PAEs on maternal and infants by 32.51 %. This study presents theoretical support for regulating PAE exposure to specific populations in the traffic environment and treating other pollutants in the future.

Exploring therapeutic potential of mitophagy modulators using Drosophila models of Parkinson’s disease

Parkinson’s disease (PD) is the second most popular age-associated neurodegenerative disorder after Alzheimer’s disease. The degeneration of dopaminergic neurons, aggregation of α-synuclein (α-syn), and locomotor defects are the main characteristic features of PD. The main cause of a familial form of PD is associated with a mutation in genes such as SNCA, PINK1, Parkin, DJ-1, LRKK2, and others. Recent advances have uncovered the different underlying mechanisms of PD but the treatment of PD is still unknown due to the unavailability of effective therapies and preventive medicines in the current scenario. The pathophysiology and genetics of PD have been strongly associated with mitochondria in disease etiology. Several studies have investigated a complex molecular mechanism governing the identification and clearance of dysfunctional mitochondria from the cell, a mitochondrial quality control mechanism called mitophagy. Reduced mitophagy and mitochondrial impairment are found in both sporadic and familial PD. Pharmacologically modulating mitophagy and accelerating the removal of defective mitochondria are of common interest in developing a therapy for PD. However, despite the extensive understanding of the mitochondrial quality control pathway and its underlying mechanism, the therapeutic potential of targeting mitophagy modulation and its role in PD remains to be explored. Thus, targeting mitophagy using chemical agents and naturally occurring phytochemicals could be an emerging therapeutic strategy in PD prevention and treatment. We discuss the current research on understanding the role of mitophagy modulators in PD using Drosophila melanogaster as a model. We further explore the contribution of Drosophila in the pathophysiology of PD, and discuss comprehensive genetic analysis in flies and pharmacological drug screening to develop potential therapeutic molecules for PD.

Lactiplantibacillus plantarum fermented barley extracts ameliorate high-fat-diet-induced muscle dysfunction via mitophagy

BACKGROUND

A reduced level of fatty acid oxidation (FAO) by skeletal muscle leads to the accumulation of intermuscular fat (IMF), which is linked to impaired exercise capacity. Previously, we have reported that Lactiplantibacillus plantarum fermented barley extract (LFBE) has effective anti-obesity properties. In this study, the effects of LFBE on muscle were investigated.

RESULTS

LFBE improved running endurance and muscle strength, which was caused by the elevation of FAO in muscle. In addition, LFBE renovated muscle regeneration through the upregulation of paired box 7 and myogenic differentiation 1 expression avoiding the injury of skeletal muscle fibers. Furthermore, total polyphenol isolated from LFBE (FTP) reinforced mobility and showed a significant protective effect on maintaining muscle fiber morphogenesis in Caenorhabditis elegans. Transmission electron microscope observation suggested FTP induced mitophagy in C. elegans body wall muscle, which was strongly connected with enhanced FAO in mitochondria.

CONCLUSIONS

Our findings highlighted the beneficial bioactivities of FTP and its potential application for stimulating mitophagy and muscle function in obese individuals. © 2022 Society of Chemical Industry.

Mitochondrial DNA Is a Vital Driving Force in Ischemia-Reperfusion Injury in Cardiovascular Diseases

According to the latest Global Burden of Disease Study, cardiovascular disease (CVD) is the leading cause of death, and ischemic heart disease and stroke are the cause of death in approximately half of CVD patients. In CVD, mitochondrial dysfunction following ischemia-reperfusion (I/R) injury results in heart failure. The proper functioning of oxidative phosphorylation (OXPHOS) and the mitochondrial life cycle in cardiac mitochondria are closely related to mitochondrial DNA (mtDNA). Following myocardial I/R injury, mitochondria activate multiple repair and clearance mechanisms to repair damaged mtDNA. When these repair mechanisms are insufficient to restore the structure and function of mtDNA, irreversible mtDNA damage occurs, leading to mtDNA mutations. Since mtDNA mutations aggravate OXPHOS dysfunction and affect mitophagy, mtDNA mutation accumulation leads to leakage of mtDNA and proteins outside the mitochondria, inducing an innate immune response, aggravating cardiovascular injury, and leading to the need for external interventions to stop or slow the disease course. On the other hand, mtDNA released into the circulation after cardiac injury can serve as a biomarker for CVD diagnosis and prognosis. This article reviews the pathogenic basis and related research findings of mtDNA oxidative damage and mtDNA leak-triggered innate immune response associated with I/R injury in CVD and summarizes therapeutic options that target mtDNA.

Sweet tea (Rubus Suavissmus S. Lee) polysaccharides promote the longevity of Caenorhabditis elegans through autophagy-dependent insulin and mitochondrial pathways

The fine structure of sweet tea polysaccharide (STP-60a) has been characterized. However, the biological activity of STP-60a has not been extensively explored. This study aims to evaluate the anti-aging activity of STP-60a using Caenorhabditis elegans (C. elegans) as a model and to investigate the underlying molecular mechanism. 400 μg/mL of STP-60a increased the mean lifespan of C. elegans by 22.88%, reduced the lipofuscin content by 33.01%, and improved the survival rate under heat stress and oxidative stress by 32.33% and 27.63%, respectively. Further research in lifespan-related mutants revealed that STP-60a exerted anti-aging effects mainly through insulin and mitochondrial signaling pathways. Through qRT-PCR and microscopic imaging of transgenic nematodes, we found that 400 μg/mL of STP-60a increased the expression of daf-16, skn-1, and hsf-1 downstream of the insulin pathway by 1.68-fold, 1.88-fold, and 1.03-fold, respectively, and promoted the accumulation of daf-16 and skn-1 in the nucleus. STP-60a also significantly regulated the function of the mitochondrial respiratory chain and unfolded protein recovery system. Furthermore, STP-60a activated the autophagy level in C. elegans, and the mutation of daf-2 or clk-1 inhibited the upregulation of autophagy genes by STP-60a, suggesting that autophagy acted as an effector of the insulin and mitochondrial pathways during STP-60a antiaging.

Ginkgo seed extract promotes longevity and stress resistance of Caenorhabditis elegans

Ginkgo seeds are a traditional food in China valued for their nutritional and health benefits. However, little is known about the anti-aging and health-promoting effects of ginkgo seed products. Here, we showed that ginkgo seed powder extract (GSP-E) is abundant in alkaloids and flavonoids, and can extend the lifespan of Caenorhabditis elegans. GSP-E improved most physiological indicators related to aging of C. elegans, including locomotor activity, reproductive capacity, and resistance to oxidation and heat. Moreover, GSP-E reduced the accumulation of lipofuscin and reactive oxygen species (ROS) in C. elegans. Further studies demonstrated that GSP-E improved longevity and stress resistance by mediating lipid metabolism and autophagy, as well as by regulating gene expression (e.g., FASN-1, POD-2, GPX-7, FAT-5). GSP-E has an anti-amyloid effect and delayed amyloid-induced paralysis of C. elegans. These findings could support the utilization of ginkgo seed as a potential dietary supplement for the health food industry, and provide a novel health-promoting resource against aging and aging-related diseases.

Polyphenols from Blumea laciniata Extended the Lifespan and Enhanced Resistance to Stress in Caenorhabditis elegans via the Insulin Signaling Pathway

Blumea laciniata is widely used as a folk medicine in Asia, but relevant literature on it is rarely reported. We confirmed that polyphenol extract (containing chlorogenic acid, rutin, and luteolin-4-O-glucoside) from B. laciniata (EBL) showed strong antioxidant ability in vitro. Hence, in this work, we applied Caenorhabditis elegans to further investigate the antioxidant and anti-ageing abilities of EBL in vivo. The results showed that EBL enhanced the survival of C. elegans under thermal stress by 12.62% and sharply reduced the reactive oxygen species level as well as the content of malonaldehyde. Moreover, EBL increased the activities of antioxidant enzymes such as catalase and superoxide dismutase. Additionally, EBL promoted DAF-16, a transcription factor, into the nucleus. Besides, EBL extended the lifespan of C. elegans by 17.39%, showing an anti-ageing effect. Different mutants indicated that the insulin/IGF-1 signaling pathway participated in the antioxidant and anti-ageing effect of EBL on C. elegans.

Flavonoids from the mung bean coat promote longevity and fitness in Caenorhabditis elegans

Mung beans possess health benefits related to their bioactive ingredients, mainly flavonoids, which are highly concentrated in the coat. However, the anti-aging effects of mung beans are rarely reported. In this work, we found that mung bean coat extract (MBCE), rich in vitexin and isovitexin, extended the lifespan and promoted the health of Caenorhabditis elegans (C. elegans) without any disadvantages. Moreover, MBCE enhanced the resistance to heat and oxidation of C. elegans by reducing the accumulation of intracellular reactive oxygen species and up-regulating the expression of stress-resistant genes or proteins. Further studies demonstrated that MBCE improved longevity, stress-resistance and fitness by mediating the mitochondrial function, mimicking calorie restriction, and altering histone modification. These findings provide direct evidence for the anti-aging effects of mung beans and new insights into the innovations and applications of mung beans for the healthcare industry.

The Review of Anti-aging Mechanism of Polyphenols on Caenorhabditis elegans

Micronutrients extracted from natural plants or made by biological synthesis are widely used in anti-aging research and applications. Among more than 30 effective anti-aging substances, employing polyphenol organic compounds for modification or delaying of the aging process attracts great interest because of their distinct contribution in the prevention of degenerative diseases, such as cardiovascular disease and cancer. There is a profound potential for polyphenol extracts in the research of aging and the related diseases of the elderly. Previous studies have mainly focused on the properties of polyphenols implicated in free radical scavenging; however, the anti-oxidant effect cannot fully elaborate its biological functions, such as neuroprotection, Aβ protein production, ion channel coupling, and signal transduction pathways. Caenorhabditis elegans (C. elegans) has been considered as an ideal model organism for exploring the mechanism of anti-aging research and is broadly utilized in screening for natural bioactive substances. In this review, we have described the molecular mechanisms and pathways responsible for the slowdown of aging processes exerted by polyphenols. We also have discussed the possible mechanisms for their anti-oxidant and anti-aging properties in C. elegans from the perspective of different classifications of the specific polyphenols, such as flavonols, anthocyanins, flavan-3-ols, hydroxybenzoic acid, hydroxycinnamic acid, and stilbenes.

mtDNA Heteroplasmy at the Core of Aging-Associated Heart Failure. An Integrative View of OXPHOS and Mitochondrial Life Cycle in Cardiac Mitochondrial Physiology

The most common aging-associated diseases are cardiovascular diseases which affect 40% of elderly people. Elderly people are prone to suffer aging-associated diseases which are not only related to health and medical cost but also to labor, household productivity and mortality cost. Aging is becoming a world problem and it is estimated that 21.8% of global population will be older than 65 years old in 2050; and for the first time in human history, there will be more elderly people than children. It is well accepted that the origin of aging-associated cardiovascular diseases is mitochondrial dysfunction. Mitochondria have their own genome (mtDNA) that is circular, double-stranded, and 16,569 bp long in humans. There are between 500 to 6000 mtDNA copies per cell which are tissue-specific. As a by-product of ATP production, reactive oxygen species (ROS) are generated which damage proteins, lipids, and mtDNA. ROS-mutated mtDNA co-existing with wild type mtDNA is called mtDNA heteroplasmy. The progressive increase in mtDNA heteroplasmy causes progressive mitochondrial dysfunction leading to a loss in their bioenergetic capacity, disruption in the balance of mitochondrial fusion and fission events (mitochondrial dynamics, MtDy) and decreased mitophagy. This failure in mitochondrial physiology leads to the accumulation of depolarized and ROS-generating mitochondria. Thus, besides attenuated ATP production, dysfunctional mitochondria interfere with proper cellular metabolism and signaling pathways in cardiac cells, contributing to the development of aging-associated cardiovascular diseases. In this context, there is a growing interest to enhance mitochondrial function by decreasing mtDNA heteroplasmy. Reduction in mtDNA heteroplasmy is associated with increased mitophagy, proper MtDy balance and mitochondrial biogenesis; and those processes can delay the onset or progression of cardiovascular diseases. This has led to the development of mitochondrial therapies based on the application of nutritional, pharmacological and genetic treatments. Those seeking to have a positive impact on mtDNA integrity, mitochondrial biogenesis, dynamics and mitophagy in old and sick hearts. This review covers the current knowledge of mitochondrial physiopathology in aging, how disruption of OXPHOS or mitochondrial life cycle alter mtDNA and cardiac cell function; and novel mitochondrial therapies to protect and rescue our heart from cardiovascular diseases.

Mitophagy and the Brain

Stress mechanisms have long been associated with neuronal loss and neurodegenerative diseases. The origin of cell stress and neuronal loss likely stems from multiple pathways. These include (but are not limited to) bioenergetic failure, neuroinflammation, and loss of proteostasis. Cells have adapted compensatory mechanisms to overcome stress and circumvent death. One mechanism is mitophagy. Mitophagy is a form of macroautophagy, were mitochondria and their contents are ubiquitinated, engulfed, and removed through lysosome degradation. Recent studies have implicated mitophagy dysregulation in several neurodegenerative diseases and clinical trials are underway which target mitophagy pathways. Here we review mitophagy pathways, the role of mitophagy in neurodegeneration, potential therapeutics, and the need for further study.