Dietary epicatechin improves survival and delays skeletal muscle degeneration in aged mice

Nutritional approaches targeting mitochondria for the prevention of sarcopenia

A decline in function and loss of mass, a condition known as sarcopenia, is observed in the skeletal muscles with aging. Sarcopenia has a negative effect on the quality of life of elderly. Individuals with sarcopenia are at particular risk for adverse outcomes, such as reduced mobility, fall-related injuries, and type 2 diabetes mellitus. Although the pathogenesis of sarcopenia is multifaceted, mitochondrial dysfunction is regarded as a major contributor for muscle aging. Hence, the development of preventive and therapeutic strategies to improve mitochondrial function during aging is imperative for sarcopenia treatment. However, effective and specific drugs that can be used for the treatment are not yet approved. Instead studies on the relationship between food intake and muscle aging have suggested that nutritional intake or dietary control could be an alternative approach for the amelioration of muscle aging. This narrative review approaches various nutritional components and diets as a treatment for sarcopenia by modulating mitochondrial homeostasis and improving mitochondria. Age-related changes in mitochondrial function and the molecular mechanisms that help improve mitochondrial homeostasis are discussed, and the nutritional components and diet that modulate these molecular mechanisms are addressed.

New Trends to Treat Muscular Atrophy: A Systematic Review of Epicatechin

Epicatechin is a polyphenol compound that promotes skeletal muscle differentiation and counteracts the pathways that participate in the degradation of proteins. Several studies present contradictory results of treatment protocols and therapeutic effects. Therefore, the objective of this systematic review was to investigate the current literature showing the molecular mechanism and clinical protocol of epicatechin in muscle atrophy in humans, animals, and myoblast cell-line. The search was conducted in Embase, PubMed/MEDLINE, Cochrane Library, and Web of Science. The qualitative analysis demonstrated that there is a commonness of epicatechin inhibitory action in myostatin expression and atrogenes MAFbx, FOXO, and MuRF1. Epicatechin showed positive effects on follistatin and on the stimulation of factors related to the myogenic actions (MyoD, Myf5, and myogenin). Furthermore, the literature also showed that epicatechin can interfere with mitochondrias' biosynthesis in muscle fibers, stimulation of the signaling pathways of AKT/mTOR protein production, and amelioration of skeletal musculature performance, particularly when combined with physical exercise. Epicatechin can, for these reasons, exhibit clinical applicability due to the beneficial results under conditions that negatively affect the skeletal musculature. However, there is no protocol standardization or enough clinical evidence to draw more specific conclusions on its therapeutic implementation.

The significance of caloric restriction mimetics as anti-aging drugs

Aging is an intricate process characterized by the gradual deterioration of the physiological integrity of a living organism. This unfortunate phenomenon inevitably leads to a decline in functionality and a heightened susceptibility to the ultimate fate of mortality. Therefore, it is of utmost importance to implement interventions that possess the capability to reverse or preempt age-related pathology. Caloric restriction mimetics (CRMs) refer to a class of molecules that have been observed to elicit advantageous outcomes on both health and longevity in various model organisms and human subjects. Notably, these compounds offer a promising alternative to the arduous task of adhering to a caloric restriction diet and mitigate the progression of the aging process and extend the duration of life in laboratory animals and human population. A plethora of molecular signals have been linked to the practice of caloric restriction, encompassing Insulin-like Growth Factor 1 (IGF1), Mammalian Target of Rapamycin (mTOR), the Adenosine Monophosphate-Activated Protein Kinase (AMPK) pathway, and Sirtuins, with particular emphasis on SIRT1. Therefore, this review will center its focus on several compounds that act as CRMs, highlighting their molecular targets, chemical structures, and mechanisms of action. Moreover, this review serves to underscore the significant relationship between post COVID-19 syndrome, antiaging, and importance of utilizing CRMs. This particular endeavor will serve as a comprehensive guide for medicinal chemists and other esteemed researchers, enabling them to meticulously conceive and cultivate novel molecular entities with the potential to function as efficacious antiaging pharmaceutical agents.

Current Nutritional and Pharmacological Approaches for Attenuating Sarcopenia

Sarcopenia is characterized by a gradual slowing of movement due to loss of muscle mass and quality, decreased power and strength, increased risk of injury from falls, and often weakness. This review will focus on recent research trends in nutritional and pharmacological approaches to controlling sarcopenia. Because nutritional studies in humans are fairly limited, this paper includes many results from nutritional studies in mammals. The combination of resistance training with supplements containing amino acids is the gold standard for preventing sarcopenia. Amino acid (HMB) supplementation alone has no significant effect on muscle strength or muscle mass in sarcopenia, but the combination of HMB and exercise (whole body vibration stimulation) is likely to be effective. Tea catechins, soy isoflavones, and ursolic acid are interesting candidates for reducing sarcopenia, but both more detailed basic research on this treatment and clinical studies in humans are needed. Vitamin D supplementation has been shown not to improve sarcopenia in elderly individuals who are not vitamin D-deficient. Myostatin inhibitory drugs have been tried in many neuromuscular diseases, but increases in muscle mass and strength are less likely to be expected. Validation of myostatin inhibitory antibodies in patients with sarcopenia has been positive, but excessive expectations are not warranted.

Small Extracellular Vesicles Maintain Homeostasis of Senescent Mesenchymal Stem Cells at Least Through Excreting Harmful Lipids

Mesenchymal stem cells (MSCs) play an essential role in multiple physiological processes in vivo and a promising cell-based therapy for various diseases. Nonetheless, MSCs suffer from senescence with expansion culture, leading to a limitation for their clinical application. Recently, it was reported that small extracellular vesicles (sEVs) are involved in regulation of senescence in tumor cells and fibroblasts. However, the biological roles of sEVs in senescent MSCs (Sen MSCs) are poorly understood. In this study, we established a replicative senescence model of MSCs by successive passages and compared the phenotypic changes between presenescent MSCs (Pre-Sen MSCs) and Sen MSCs and found that Sen MSCs exhibited a diminished adipogenic and osteogenic differentiation potential and elevated senescence-associated secretory phenotype levels. In addition, we found that sEV secretion was increased in Sen MSCs, and inhibition of sEV secretion led to apoptosis, DNA damage, and decreased cell viability, suggesting that increased sEV secretion plays an important role in maintaining Sen MSC homeostasis. To further investigate the molecular mechanisms, metabolomic profiling of Pre-Sen MSC-derived sEVs (Pre-Sen-sEVs) and Sen MSC-derived sEVs (Sen-sEVs) was performed. The results showed that lipid metabolites were significantly increased in Sen-sEVs and these significantly upregulated lipid metabolites were shown to be toxic for inducing cellular senescence and apoptosis in previous studies. Kyoto Encyclopedia of Genes and Genomes analysis revealed enrichment of differential metabolites between Pre-Sen-sEVs and Sen-sEVs mainly in 25 signaling pathways, of which 21 metabolic pathways have been shown to be closely associated with senescence. Taken together, our findings suggested that increased sEV secretion maintains Sen MSC homeostasis, at least in part, by excreting harmful lipids, thus providing new insights into the regulation of senescence by sEVs.

Higher intake of dietary flavonols, specifically dietary quercetin, is associated with lower odds of frailty onset over 12 years of follow-up among adults in the Framingham Heart Study

BACKGROUND

Polyphenolic antioxidants derived from plant foods may reduce oxidative stress and frailty, but the effect of the polyphenol subclass of dietary flavonoids and their subclasses on frailty is uncertain.

OBJECTIVES

To determine the association between dietary flavonoids, their subclasses, quercetin (a specific flavonol), and frailty onset in adults.

METHODS

This prospective cohort study included individuals from the Framingham Heart Study with no frailty at baseline. Intake of total flavonoids, subclasses of flavonoids (flavonols, flavan-3-ols, flavonones, flavones, anthocyanins, and polymeric flavonoids), and quercetin were estimated via semi-quantitative FFQ along with frailty (Fried phenotype), and covariates at baseline (1998-2001). Frailty was re-evaluated in 2011-2014. Logistic regression estimated OR and 95% CIs for each flavonoid variable and frailty onset.

RESULTS

Mean age was 58.4 y (SD ± 8.3, n = 1701; 55.5% women). The mean total flavonoid intake was 309 mg/d (SD ± 266). After 12.4 (SD ± 0.8) y, 224 (13.2%) individuals developed frailty. Although total flavonoid intake was not statistically associated with frailty onset (adjusted OR: 1.00; 95% CI: 0.99-1.01), each 10 mg/d of higher flavonol intake was linked with 20% lower odds of frailty onset (OR: 0.80; 95% CI: 0.67-0.96). Other subclasses showed no association (P values range: 0.12-0.99), but every 10 mg/d of higher quercetin intake was associated with 35% lower odds of frailty onset (OR: 0.65; 95% CI: 0.48-0.88).

CONCLUSIONS

Although no association was observed between total flavonoid intake and frailty onset in adults, a higher intake of flavonols was associated with lower odds of frailty onset, with a particularly strong association for quercetin. This hypothesis-generating study highlights the importance of assessing specific subclasses of flavonoids and the potential of dietary flavonols and quercetin as a strategy to prevent the development of frailty.

Sarcopenic Obesity: Involvement of Oxidative Stress and Beneficial Role of Antioxidant Flavonoids

Sarcopenic obesity, which refers to concurrent sarcopenia and obesity, is characterized by decreased muscle mass, strength, and performance along with abnormally excessive fat mass. Sarcopenic obesity has received considerable attention as a major health threat in older people. However, it has recently become a health problem in the general population. Sarcopenic obesity is a major risk factor for metabolic syndrome and other complications such as osteoarthritis, osteoporosis, liver disease, lung disease, renal disease, mental disease and functional disability. The pathogenesis of sarcopenic obesity is multifactorial and complicated, and it is caused by insulin resistance, inflammation, hormonal changes, decreased physical activity, poor diet and aging. Oxidative stress is a core mechanism underlying sarcopenic obesity. Some evidence indicates a protective role of antioxidant flavonoids in sarcopenic obesity, although the precise mechanisms remain unclear. This review summarizes the general characteristics and pathophysiology of sarcopenic obesity and focuses on the role of oxidative stress in sarcopenic obesity. The potential benefits of flavonoids in sarcopenic obesity have also been discussed.

Anti-aging effects of dietary phytochemicals: From Caenorhabditis elegans, Drosophila melanogaster, rodents to clinical studies

Anti-aging research has become critical since the elderly population is increasing dramatically in this era. With the establishment of frailty phenotype and frailty index, the importance of anti-frailty research is concurrently enlightened. The application of natural phytochemicals against aging or frailty is always intriguing, and abundant related studies have been published. Various models are designed for biological research, and each model has its strength and weakness in deciphering the complex aging mechanisms. In this article, we attempt to show the potential of Caenorhabditis elegans in the study of phytochemicals' effects on anti-aging by comparing it to other animal models. In this review, the lifespan extension and anti-aging effects are demonstrated by various physical, cellular, or molecular biomarkers of dietary phytochemicals, including resveratrol, curcumin, urolithin A, sesamin, fisetin, quercetin, epigallocatechin-3-gallate, epicatechin, spermidine, sulforaphane, along with extracts of broccoli, cocoa, and blueberry. Meanwhile, the frequency of phytochemicals and models studied or presented in publications since 2010 were analyzed, and the most commonly mentioned animal models were rats, mice, and the nematode C. elegans. This up-to-date summary of the anti-aging effect of certain phytochemicals has demonstrated powerful potential for anti-aging or anti-frailty in the human population.

Effects of black soldier fly larvae as protein or fat sources on apparent nutrient digestibility, fecal microbiota, and metabolic profiles in beagle dogs

Black soldier fly (Hermetia illucens) larvae (BSFL) act as a biological system converting organic waste into protein and fat with great potential application as pet food. To evaluate the feasibility of BSFL as a protein and fat source, 20 healthy beagle dogs were fed three dietary treatments for 65 days, including (1) a basal diet group (CON group), (2) a basal diet that replaced 20% chicken meal with defatted black soldier fly larvae protein group (DBP group), and (3) a basal diet that replaced 8% mixed oil with black soldier fly larvae fat group (BF group). This study demonstrated that the serum biochemical parameters among the three groups were within the normal range. No difference (p > 0.05) was observed in body weight, body condition score, or antioxidant capacity among the three groups. The mean IFN-γ level in the BF group was lower than that in the CON group, but there was no significant difference (p > 0.05). Compared with the CON group, the DBP group had decreasing (p < 0.05) apparent crude protein and organic matter digestibility. Furthermore, the DBP group had decreasing (p < 0.05) fecal propionate, butyrate, total short-chain fatty acids (SCFAs), isobutyrate, isovalerate, and total branched-chain fatty acids (BCFAs) and increased (p < 0.05) fecal pH. Nevertheless, there was no difference (p > 0.05) in SCFAs or BCFAs between the CON and BF groups. The fecal microbiota revealed that Lachnoclostridium, Clostridioides, Blautia, and Enterococcus were significantly enriched in the DBP group, and Terrisporobacter and Ralstonia were significantly enriched in the BF group. The fecal metabolome showed that the DBP group significantly influenced 18 metabolic pathways. Integrating biological and statistical correlation analysis on differential fecal microbiota and metabolites between the CON and DBP groups found that Lachnoclostridium, Clostridioides, and Enterococcus were positively associated with biotin. In addition, Lachnoclostridium, Clostridioides, Blautia, and Enterococcus were positively associated with niacinamide, phenylalanine acid, fumaric acid, and citrulline and negatively associated with cadavrine, putrescine, saccharopine, and butyrate. In all, 20% DBP restrained the apparent CP and OM digestibility, thereby affecting hindgut microbial metabolism. In contrast, 8% BF in the dog diet showed no adverse effects on body condition, apparent nutrient digestibility, fecal microbiota, or metabolic profiles. Our findings are conducive to opening a new avenue for the exploitation of DBP and BF as protein and fat resources in dog food.

Epigallocatechin-3-Gallate Improves Intestinal Gut Microbiota Homeostasis and Ameliorates Clostridioides difficile Infection

Clostridioides difficile infection is closely related to the intestinal flora disorders induced by antibiotics, and changes in the intestinal flora may cause the occurrence and development of Clostridioides difficile infection. Epigallocatechin-3-gallate (EGCG) is one of the major bioactive ingredients of green tea and has been suggested to alleviate the growth of C. difficile in vitro. EGCG can ameliorate several diseases, such as obesity, by regulating the gut microbiota. However, whether EGCG can attenuate C. difficile infection by improving the gut microbiota is unknown. After establishing a mouse model of C. difficile infection, mice were administered EGCG (25 or 50 mg/kg/day) or PBS intragastrically for 2 weeks to assess the benefits of EGCG. Colonic pathology, inflammation, the intestinal barrier, gut microbiota composition, metabolomics, and the transcriptome were evaluated in the different groups. Compared with those of the mice in the CDI group, EGCG improved survival rates after infection, improved inflammatory markers, and restored the damage to the intestinal barrier. Furthermore, EGCG could improve the intestinal microbial community caused by C. difficile infection, such as by reducing the relative abundance of Enterococcaceae and Enterobacteriaceae. Moreover, EGCG can increase short-chain fatty acids, improve amino acid metabolism, and downregulate pathways related to intestinal inflammation. EGCG alters the microbiota and alleviates C. difficile infection, which provides new insights into potential therapies.

Molecular Mechanisms of Inflammation in Sarcopenia: Diagnosis and Therapeutic Update

Sarcopenia is generally an age-related condition that directly impacts the quality of life. It is also related to chronic diseases such as metabolic dysfunction associated with diabetes and obesity. This means that everyone will be vulnerable to sarcopenia at some point in their life. Research to find the precise molecular mechanisms implicated in this condition can increase knowledge for the better prevention, diagnosis, and treatment of sarcopenia. Our work gathered the most recent research regarding inflammation in sarcopenia and new therapeutic agents proposed to target its consequences in pyroptosis and cellular senescence. Finally, we compared dual X-ray absorptiometry (DXA), magnetic resonance imaging (MRI), and ultrasound (US) as imaging techniques to diagnose and follow up on sarcopenia, indicating their respective advantages and disadvantages. Our goal is for the scientific evidence presented here to help guide future research to understand the molecular mechanisms involved in sarcopenia, new treatment strategies, and their translation into clinical practice.

The Role of Antioxidants in the Interplay between Oxidative Stress and Senescence

Cellular senescence is an irreversible state of cell cycle arrest occurring in response to stressful stimuli, such as telomere attrition, DNA damage, reactive oxygen species, and oncogenic proteins. Although beneficial and protective in several physiological processes, an excessive senescent cell burden has been involved in various pathological conditions including aging, tissue dysfunction and chronic diseases. Oxidative stress (OS) can drive senescence due to a loss of balance between pro-oxidant stimuli and antioxidant defences. Therefore, the identification and characterization of antioxidant compounds capable of preventing or counteracting the senescent phenotype is of major interest. However, despite the considerable number of studies, a comprehensive overview of the main antioxidant molecules capable of counteracting OS-induced senescence is still lacking. Here, besides a brief description of the molecular mechanisms implicated in OS-mediated aging, we review and discuss the role of enzymes, mitochondria-targeting compounds, vitamins, carotenoids, organosulfur compounds, nitrogen non-protein molecules, minerals, flavonoids, and non-flavonoids as antioxidant compounds with an anti-aging potential, therefore offering insights into innovative lifespan-extending approaches.

Assessment of Feed Value of Chicory and Lucerne for Poultry, Determination of Bioaccessibility of Their Polyphenols and Their Effects on Caecal Microbiota

Chicory and lucerne possess high feed value for poultry being good sources of protein and fiber. In addition, they are rich in polyphenols that help the body build an integrated antioxidant system to prevent damage from free radicals and positively modulate microbial populations in the gastrointestinal tract. These health-promoting effects of polyphenols depend on their bioaccessibility and absorption in the animal body. The present paper aimed to study the bioaccessibility of polyphenols from chicory and lucerne after subjecting the samples to gastric and intestinal phases of digestion in an in vitro model of chicken gut and assessment of their feed value by measuring the presence of fermentable substrates (in terms of gas production), SCFAs produced and their effects on gut microbiota population during in vitro cecal fermentation. Results revealed that the bioaccessibility of polyphenols varied with different polyphenol compounds. The highest bioaccessibility was recorded for p-hydroxybenzoic acid (90.8%) from chicory following the intestinal phase of digestion. The lowest bioaccessibility was observed for quercetin-3-rhamnoside (12.6%) from chicory after the gastric phase of digestion. From lucerne, the highest bioaccessibility was recorded for kaempferol-3-glucoside (77.5%) after the intestinal phase of digestion. Total gas production was higher for lucerne (39.9 mL/g) than chicory (28.1 mL/g). Similarly, total SCFAs production was higher after 24 h of cecal fermentation with lucerne (42.2 mmol L−1) as compared to chicory (38.1 mmol L−1). Results also revealed that the relative abundance of Clostridium was reduced with chicory (0.225%) and lucerne (0.176%) as compared to the control (0.550%) after 24 h of cecal fermentation. The relative abundance of Streptococcus was reduced by lucerne (4.845%) but was increased with chicory (17.267%) as compared to the control (5.204%) after 24 h of fermentation. These findings indicated that chicory and lucerne differentially affected the microbial populations during in vitro cecal fermentation.

Natural products: Potential therapeutic agents to prevent skeletal muscle atrophy

The skeletal muscle (SkM) is the largest organ, which plays a vital role in controlling musculature, locomotion, body heat regulation, physical strength, and metabolism of the body. A sedentary lifestyle, aging, cachexia, denervation, immobilization, etc. Can lead to an imbalance between protein synthesis and degradation, which is further responsible for SkM atrophy (SmA). To date, the understanding of the mechanism of SkM mass loss is limited which also restricted the number of drugs to treat SmA. Thus, there is an urgent need to develop novel approaches to regulate muscle homeostasis. Presently, some natural products attained immense attraction to regulate SkM homeostasis. The natural products, i.e., polyphenols (resveratrol, curcumin), terpenoids (ursolic acid, tanshinone IIA, celastrol), flavonoids, alkaloids (tomatidine, magnoflorine), vitamin D, etc. exhibit strong potential against SmA. Some of these natural products have been reported to have equivalent potential to standard treatments to prevent body lean mass loss. Indeed, owing to the large complexity, diversity, and slow absorption rate of bioactive compounds made their usage quite challenging. Moreover, the use of natural products is controversial due to their partially known or elusive mechanism of action. Therefore, the present review summarizes various experimental and clinical evidence of some important bioactive compounds that shall help in the development of novel strategies to counteract SmA elicited by various causes.

Beneficial Effects of Flavonoids on Skeletal Muscle Health: A Systematic Review and Meta-Analysis

Skeletal muscle (SkM) is a highly dynamic tissue that responds to physiological adaptations or pathological conditions, and SkM mitochondria play a major role in bioenergetics, regulation of intracellular calcium homeostasis, pro-oxidant/antioxidant balance, and apoptosis. Flavonoids are polyphenolic compounds with the ability to modulate molecular pathways implicated in the development of mitochondrial myopathy. Therefore, it is pertinent to explore its potential application in conditions such as aging, disuse, denervation, diabetes, obesity, and cancer. To evaluate preclinical and clinical effects of flavonoids on SkM structure and function. We performed a systematic review of published studies, with no date restrictions applied, using PubMed and Scopus. The following search terms were used: "flavonoids" OR "flavanols" OR "flavones" OR "anthocyanidins" OR "flavanones" OR "flavan-3-ols" OR "catechins" OR "epicatechin" OR "(-)-epicatechin" AND "skeletal muscle." The studies included in this review were preclinical studies, clinical trials, controlled clinical trials, and randomized-controlled trials that investigated the influence of flavonoids on SkM health. Three authors, independently, assessed trials for the review. Any disagreement was resolved by consensus. The use of flavonoids could be a potential tool for the prevention of muscle loss. Their effects on metabolism and on mitochondria function suggest their use as muscle regulators.

Flavonoids-Natural Gifts to Promote Health and Longevity

The aging of mammals is accompanied by the progressive atrophy of tissues and organs and the accumulation of random damage to macromolecular DNA, protein, and lipids. Flavonoids have excellent antioxidant, anti-inflammatory, and neuroprotective effects. Recent studies have shown that flavonoids can delay aging and prolong a healthy lifespan by eliminating senescent cells, inhibiting senescence-related secretion phenotypes (SASPs), and maintaining metabolic homeostasis. However, only a few systematic studies have described flavonoids in clinical treatment for anti-aging, which needs to be explored further. This review first highlights the association between aging and macromolecular damage. Then, we discuss advances in the role of flavonoid molecules in prolonging the health span and lifespan of organisms. This study may provide crucial information for drug design and developmental and clinical applications based on flavonoids.

( -)-Epicatechin and cardiometabolic risk factors: a focus on potential mechanisms of action

This review summarizes experimental evidence on the beneficial effects of ( -)-epicatechin (EC) attenuating major cardiometabolic risk factors, i.e., dyslipidemias, obesity (adipose tissue dysfunction), hyperglycemia (insulin resistance), and hypertension (endothelial dysfunction). Studies in humans are revised and complemented with experiments in animal models, and cultured cells, aiming to understand the molecular mechanisms involved in EC-mediated effects. Firstly, an assessment of EC metabolism gives relevance to both conjugated-EC metabolites product of host metabolism and microbiota-derived species. Integration and analysis of results stress the maintenance of redox homeostasis and mitigation of inflammation as relevant processes associated with cardiometabolic diseases. In these processes, EC appears having significant effects regulating NADPH oxidase (NOX)-dependent oxidant production, nitric oxide (NO) production, and energy homeostasis (mitochondrial biogenesis and function). The potential participation of cell membranes and membrane-bound receptors is also discussed in terms of direct molecular action of EC and EC metabolites reaching cells and tissues.

Restorative potential of (-)-epicatechin in a rat model of Gulf War illness muscle atrophy and fatigue

We examined in a rat model of Gulf War illness (GWI), the potential of (-)-epicatechin (Epi) to reverse skeletal muscle (SkM) atrophy and dysfunction, decrease mediators of inflammation and normalize metabolic perturbations. Male Wistar rats (n = 15) were provided orally with pyridostigmine bromide (PB) 1.3 mg/kg/day, permethrin (PM) 0.13 mg/kg/day (skin), DEET 40 mg/kg/day (skin) and were physically restrained for 5 min/day for 3 weeks. A one-week period ensued to fully develop the GWI-like profile followed by 2 weeks of either Epi treatment at 1 mg/kg/day by gavage (n = 8) or water (n = 7) for controls. A normal, control group (n = 15) was given vehicle and not restrained. At 6 weeks, animals were subjected to treadmill and limb strength testing followed by euthanasia. SkM and blood sampling was used for histological, biochemical and plasma pro-inflammatory cytokine and metabolomics assessments. GWI animals developed an intoxication profile characterized SkM atrophy and loss of function accompanied by increases in modulators of muscle atrophy, degradation markers and plasma pro-inflammatory cytokine levels. Treatment of GWI animals with Epi yielded either a significant partial or full normalization of the above stated indicators relative to normal controls. Plasma metabolomics revealed that metabolites linked to inflammation and SkM waste pathways were dysregulated in the GWI group whereas Epi, attenuated such changes. In conclusion, in a rat model of GWI, Epi partially reverses detrimental changes in SkM structure including modulators of atrophy, inflammation and select plasma metabolites yielding improved function.

Prospective Selective Mechanism of Emerging Senolytic Agents Derived from Flavonoids

Senescent cells (SCs) are associated with the onset and development of multiple chronic diseases. Selective clearance of SCs by senolytic drugs is a potential therapeutic option for a number of age-related diseases. Among senolytic candidates, only dasatinib with quercetin and fisetin meet the rigorous criteria for senolytic drugs, according to a modified version of Koch's postulates. It is astonishing that two of the three agents, i.e., quercetin and fisetin, are flavonoids, although the mechanism by which they preferentially eliminate SCs is unclear. Herein, we propose a possible selective mechanism; prooxidant activities of quercetin or fisetin are inevitably involved in killing apoptosis-resistant SCs. Among the dietary flavonoids, quercetin is a potent redox-active flavonoid with strong prooxidant activities, and transition metals, such as copper and iron, hugely amplify its prooxidant activities. Fisetin, which has higher senolytic activities than quercetin, has higher prooxidant effects than quercetin in the absence or presence of copper. It appears that the prooxidant activity of flavonoids is an important consideration for screening senolytics. SCs accumulate high levels of copper and iron, and the selective mechanism of quercetin or fisetin is probably associated with copper/iron-promoted oxidative damage in SCs. Copper and iron dramatically enhanced the prooxidant effects of the flavonoid, epigallocatechin-3-gallate, having shown a depletion effect on SCs in rats and high therapeutic efficacy in patients with idiopathic pulmonary fibrosis, largely caused by SCs. Further investigation to evaluate whether epigallocatechin-3-gallate is a senolytic drug, according to Koch's postulates, is warranted.

Anti-aging properties of phytoconstituents and phyto-nanoemulsions and their application in managing aging-related diseases

Aging is spontaneous and inevitable process in all living beings. It is a complex natural phenomenon that manifests as a gradual decline of physiological functions and homeostasis. Aging inevitably leads to age-associated injuries, diseases, and eventually death. The research on aging-associated diseases aimed at delaying, preventing or even reversing the aging process are of great significance for healthy aging and also for scientific progress. Numerous plant-derived compounds have anti-aging effects, but their therapeutic potential is limited due to their short shelf-life and low bioavailability. As the novel delivery system, nanoemulsion can effectively improve this defect. Nanoemulsions enhance the delivery of drugs to the target site, maintain the plasma concentration for a longer period, and minimize adverse reaction and side effects. This review describes the importance of nanoemulsions for the delivery of phyto-derived compounds and highlights the importance of nanoemulsions in the treatment of aging-related diseases. It also covers the methods of preparation, fate and safety of nanoemulsions, which will provide valuable information for the development of new strategies in treatment of aging-related diseases.

Polyphenols and Their Effects on Muscle Atrophy and Muscle Health

Skeletal muscle atrophy is the decrease in muscle mass and strength caused by reduced protein synthesis/accelerated protein degradation. Various conditions, such as denervation, disuse, aging, chronic diseases, heart disease, obstructive lung disease, diabetes, renal failure, AIDS, sepsis, cancer, and steroidal medications, can cause muscle atrophy. Mechanistically, inflammation, oxidative stress, and mitochondrial dysfunction are among the major contributors to muscle atrophy, by modulating signaling pathways that regulate muscle homeostasis. To prevent muscle catabolism and enhance muscle anabolism, several natural and synthetic compounds have been investigated. Recently, polyphenols (i.e., natural phytochemicals) have received extensive attention regarding their effect on muscle atrophy because of their potent antioxidant and anti-inflammatory properties. Numerous in vitro and in vivo studies have reported polyphenols as strongly effective bioactive molecules that attenuate muscle atrophy and enhance muscle health. This review describes polyphenols as promising bioactive molecules that impede muscle atrophy induced by various proatrophic factors. The effects of each class/subclass of polyphenolic compounds regarding protection against the muscle disorders induced by various pathological/physiological factors are summarized in tabular form and discussed. Although considerable variations in antiatrophic potencies and mechanisms were observed among structurally diverse polyphenolic compounds, they are vital factors to be considered in muscle atrophy prevention strategies.

Beneficial effects of dietary supplementation with green tea catechins and cocoa flavanols on aging-related regressive changes in the mouse neuromuscular system

Besides skeletal muscle wasting, sarcopenia entails morphological and molecular changes in distinct components of the neuromuscular system, including spinal cord motoneurons (MNs) and neuromuscular junctions (NMJs); moreover, noticeable microgliosis has also been observed around aged MNs. Here we examined the impact of two flavonoid-enriched diets containing either green tea extract (GTE) catechins or cocoa flavanols on age-associated regressive changes in the neuromuscular system of C57BL/6J mice. Compared to control mice, GTE- and cocoa-supplementation significantly improved the survival rate of mice, reduced the proportion of fibers with lipofuscin aggregates and central nuclei, and increased the density of satellite cells in skeletal muscles. Additionally, both supplements significantly augmented the number of innervated NMJs and their degree of maturity compared to controls. GTE, but not cocoa, prominently increased the density of VAChT and VGluT2 afferent synapses on MNs, which were lost in control aged spinal cords; conversely, cocoa, but not GTE, significantly augmented the proportion of VGluT1 afferent synapses on aged MNs. Moreover, GTE, but not cocoa, reduced aging-associated microgliosis and increased the proportion of neuroprotective microglial phenotypes. Our data indicate that certain plant flavonoids may be beneficial in the nutritional management of age-related deterioration of the neuromuscular system.

(-)-Epicatechin-Enriched Extract from Camellia sinensis Improves Regulation of Muscle Mass and Function: Results from a Randomized Controlled Trial

Loss of skeletal muscle mass and function with age represents an important source of frailty and functional decline in the elderly. Antioxidants from botanical extracts have been shown to enhance the development, mass, and strength of skeletal muscle by influencing age-related cellular and molecular processes. Tannase-treated green tea extract contains high levels of the antioxidants (-)-epicatechin (EC) and gallic acid that may have therapeutic benefits for age-related muscle decline. The aim of this study was to investigate the effect of tannase-treated green tea extract on various muscle-related parameters, without concomitant exercise, in a single-center, randomized, double-blind, placebo-controlled study. Administration of tannase-treated green tea extract (600 mg/day) for 12 weeks significantly increased isokinetic flexor muscle and handgrip strength in the treatment group compared with those in the placebo (control) group. In addition, the control group showed a significant decrease in arm muscle mass after 12 weeks, whereas no significant change was observed in the treatment group. Blood serum levels of follistatin, myostatin, high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, IL-8, insulin-like growth factor-1 (IGF-1), and cortisol were analyzed, and the decrease in myostatin resulting from the administration of tannase-treated green tea extract was found to be related to the change in muscle mass and strength. In summary, oral administration of tannase-treated green tea extract containing antioxidants without concomitant exercise can improve muscle mass and strength and may have therapeutic benefits in age-related muscle function decline.

Regulation of Cytochrome c Oxidase by Natural Compounds Resveratrol, (-)-Epicatechin, and Betaine

Numerous naturally occurring molecules have been studied for their beneficial health effects. Many compounds have received considerable attention for their potential medical uses. Among them, several substances have been found to improve mitochondrial function. This review focuses on resveratrol, (–)-epicatechin, and betaine and summarizes the published data pertaining to their effects on cytochrome c oxidase (COX) which is the terminal enzyme of the mitochondrial electron transport chain and is considered to play an important role in the regulation of mitochondrial respiration. In a variety of experimental model systems, these compounds have been shown to improve mitochondrial biogenesis in addition to increased COX amount and/or its enzymatic activity. Given that they are inexpensive, safe in a wide range of concentrations, and effectively improve mitochondrial and COX function, these compounds could be attractive enough for possible therapeutic or health improvement strategies.

Dietary Anti-Aging Polyphenols and Potential Mechanisms

For years, the consumption of a diet rich in fruits and vegetables has been considered healthy, increasing longevity, and decreasing morbidities. With the assistance of basic research investigating the potential mechanisms, it has become clear that the beneficial effects of plant-based foods are mainly due to the large amount of bioactive phenolic compounds contained. Indeed, substantial dietary intervention studies in humans have supported that the supplementation of polyphenols have various health-promoting effects, especially in the elderly population. In vitro examinations on the anti-aging mechanisms of polyphenols have been widely performed, using different types of natural and synthetic phenolic compounds. The aim of this review is to critically evaluate the experimental evidence demonstrating the beneficial effects of polyphenols on aging-related diseases. We highlight the potential anti-aging mechanisms of polyphenols, including antioxidant signaling, preventing cellular senescence, targeting microRNA, influencing NO bioavailability, and promoting mitochondrial function. While the trends on utilizing polyphenols in preventing aging-related disorders are getting growing attention, we suggest the exploration of the beneficial effects of the combination of multiple polyphenols or polyphenol-rich foods, as this would be more physiologically relevant to daily life.

Dietary Epicatechin, A Novel Anti-aging Bioactive Small Molecule

Epicatechin (EC), a flavonoid present in various foods including cocoa, dark chocolate, berries, and tea, has recently been reported to promote general health and survival of old mice fed a standard chow diet. This is considered a novel discovery in the field of identifying natural compounds to extend lifespan, given that presumably popular anti-aging natural agents including resveratrol, green tea extract, and curcumin had failed in extending the lifespan of standard chow-diet-fed mice. However, the anti-aging mechanism of EC is not fully understood, thus impeding the potential application of this natural compound in improving a healthy lifespan in humans. In this review, we first summarized the main dietary sources that contain a significant amount of EC and recent research regarding the absorption, metabolism and distribution of EC in humans and rodents. The review is then focused on the anti-aging effects of EC in cultured cells, animals and humans with the possible physiological, cellular and molecular mechanisms underlying its lifespan-extending effects.

Frailty syndrome: A target for functional nutrients?

Frailty is a late life phenotype characterized by a decline in physiological reserve across several organ systems, resulting in the increased susceptibility to endogenous and/or exogenous stressors. Although the etiology of frailty remains poorly understood, an interconnected network of putative mechanisms linked to the ageing process has been proposed. However, frailty is a dynamic process that may be prevented, delayed, or even reversed. The syndromic nature of frailty requires a multidomain approach, such as proper nutrition, as part of modifiable environmental factors, and represents one of the most promising and least costly ways to prevent and reduce frailty among older adults. Nutrient deficiencies have been consistently associated with frailty; however, mounting evidence also supports the hypothesis that beyond the traditional nutritional value, specific dietary components may exert function-enhancing effects and mitigate the extent of frailty. Thus, further mechanistic studies, along with large clinical trials, are imperative to establish the exact role of functional nutrients in the clinical management of frailty. Here, we provide a contemporary discussion of how emerging functional nutrients may contribute to modify the trajectory of the frailty syndrome.

(-)-Epicatechin induces mitochondrial biogenesis and markers of muscle regeneration in adults with Becker muscular dystrophy

Introduction

We conducted an open‐label study to examine the effects of the flavonoid (−)‐epicatechin in seven ambulatory adult patients with Becker muscular dystrophy (BMD).

Methods

Seven participants received (−)‐epicatechin 50 mg twice per day for 8 weeks. Pre‐ and postprocedures included biceps brachii biopsy to assess muscle structure and growth‐relevant endpoints by western blotting, mitochondria volume measurement, and cristae abundance by electron microscopy, graded exercise testing, and muscle strength and function tests.

Results

Western blotting showed significantly increased levels of enzymes modulating cellular bioenergetics (liver kinase B1 and 5′‐adenosine monophosphate–activated protein kinase). Peroxisome proliferator‐activated receptor gamma coactivator‐1alpha, a transcriptional coactivator of genes involved in mitochondrial biogenesis and cristae‐associated mitofilin levels, increased as did cristae abundance. Muscle and plasma follistatin increased significantly while myostatin decreased. Markers of skeletal muscle regeneration myogenin, myogenic regulatory factor‐5, myoblast determination protein 1, myocyte enhancer factor‐2, and structure‐associated proteins, including dysferlin, utrophin, and intracellular creatine kinase, also increased. Exercise testing demonstrated decreased heart rate, maximal oxygen consumption per kilogram, and plasma lactate levels at defined workloads. Tissue saturation index improved in resting and postexercise states.

Discussion

(−)‐Epicatechin, an exercise mimetic, appears to have short‐term positive effects on tissue biomarkers indicative of mitochondrial biogenesis and muscle regeneration, and produced improvements in graded exercise testing parameters in patients with BMD.

Flavonoids: nutraceutical potential for counteracting muscle atrophy

Skeletal muscle plays a vital role in the conversion of chemical energy into physical force. Muscle atrophy, characterized by a reduction in muscle mass, is a symptom of chronic disease (cachexia), aging (sarcopenia), and muscle disuse (inactivity). To date, several trials have been conducted to prevent and inhibit muscle atrophy development; however, few interventions are currently available for muscle atrophy. Recently, food ingredients, plant extracts, and phytochemicals have received attention as treatment sources to prevent muscle wasting. Flavonoids are bioactive polyphenol compounds found in foods and plants. They possess diverse biological activities, including anti-obesity, anti-diabetes, anti-cancer, anti-oxidation, and anti-inflammation. The effects of flavonoids on muscle atrophy have been investigated by monitoring molecular mechanisms involved in protein turnover, mitochondrial activity, and myogenesis. This review summarizes the reported effects of flavonoids on sarcopenia, cachexia, and disuse muscle atrophy, thus, providing an insight into the understanding of the associated molecular mechanisms.

Nutraceuticals and Exercise against Muscle Wasting during Cancer Cachexia

Cancer cachexia (CC) is a debilitating multifactorial syndrome, involving progressive deterioration and functional impairment of skeletal muscles. It affects about 80% of patients with advanced cancer and causes premature death. No causal therapy is available against CC. In the last few decades, our understanding of the mechanisms contributing to muscle wasting during cancer has markedly increased. Both inflammation and oxidative stress (OS) alter anabolic and catabolic signaling pathways mostly culminating with muscle depletion. Several preclinical studies have emphasized the beneficial roles of several classes of nutraceuticals and modes of physical exercise, but their efficacy in CC patients remains scant. The route of nutraceutical administration is critical to increase its bioavailability and achieve the desired anti-cachexia effects. Accumulating evidence suggests that a single therapy may not be enough, and a bimodal intervention (nutraceuticals plus exercise) may be a more effective treatment for CC. This review focuses on the current state of the field on the role of inflammation and OS in the pathogenesis of muscle atrophy during CC, and how nutraceuticals and physical activity may act synergistically to limit muscle wasting and dysfunction.

Metabolomics Study of Whole-body Vibration on Lipid Metabolism of Skeletal Muscle in Aging Mice

Ageing increases the occurrence and development of many diseases. Exercise is believed to be an effective way to improve ageing and skeletal muscle atrophy. However, many elderly people are unable to engage in active exercise. Whole-body vibration is a passive way of moving that is especially suitable for the elderly and people who find it inconvenient to exercise. Metabolomics is the systematic study of metabolic changes in small molecules. In this study, metabolomics studies were performed to investigate the regulatory effect of whole-body vibration on the skeletal muscles of ageing mice. After 12 weeks, we found that whole-body vibration had the most obvious effect on lipid metabolism pathways (such as linoleic acid, α-linolenic acid metabolism, glycerophospholipid metabolism pathways) in skeletal muscle of ageing mice. Through further research we found that whole-body vibration decreased the levels of triglycerides, total cholesterol, low-density lipoprotein cholesterol and very low-density lipoprotein in blood; decreased the lipid deposition in skeletal muscle; decreased the protein expression of monocyte chemoattractant protein-1 and interleukin-6; improved the protein levels of phosphorylated insulin receptor substrate-1, phosphate phosphoinositide 3-kinase and p-AKT; improved the protein levels of klotho; and decreased the protein expression of p53. These findings reveal that whole-body vibration might postpone senility by attenuating lipid deposition and reducing chronic inflammation and the insulin resistance of skeletal muscle.

High Flavonoid Cocoa Supplement Ameliorates Plasma Oxidative Stress and Inflammation Levels While Improving Mobility and Quality of Life in Older Subjects: A Double-Blind Randomized Clinical Trial

BACKGROUND

The age-related decline in mass, strength, and performance of skeletal muscle is associated with loss of independence, falls risk, disability, institutionalization, and death.

METHODS

To determine whether a cocoa supplement enriched in flavonoids can improve plasma markers of oxidative stress and inflammation, physical performance and frailty in middle-aged and older subjects, we conducted a two-phase, randomized, double-blind, clinical trial. The initial study included 60 subjects (55- to 70-year-old) allocated into placebo (P), highly alkalinized (no-flavonoid; NF), or flavonoid-rich natural cocoa (F) beverage groups. The follow-up study included 74 older subjects (65- to 90-year-old) randomly distributed into NF or F groups. Subjects were instructed to consume the beverages once/day for up to 12-weeks. A comprehensive (aging relevant) set of end points were assessed, which included mean change in blood plasma metabolic and oxidative stress indicators, in physical performance tests and quality of life (QoL).

RESULTS

In the initial study, the F group showed improved glycemia, triglyceridemia, High-density lipoprotein cholesterol, Low-density lipoprotein cholesterol, triglyceridemia/HDL index, and oxidative markers. Performance on the Up and Go test, skeletal muscle index, and quality of life also improved. In the follow-up study, F treatment was associated with significant improvements in metabolic, oxidative stress, and inflammatory endpoints and positive effects on physical performance, frailty indicators, and quality of life (F vs. NF group).

CONCLUSIONS

Regular flavonoids consumption positively affects blood oxidative stress and inflammation end points, cardiometabolic risk markers, physical performance, and quality of life. The sum of such effects may help to mitigate the extent of frailty development in the elderly people.

TRIAL REGISTRATION

NCT03585868.

Muscle Disuse Atrophy Caused by Discord of Intracellular Signaling

Significance: Regular contractile activity plays a critical role in maintaining skeletal muscle morphological integrity and physiological function. If the muscle is forced to stop contraction, such as during limb immobilization (IM), the IGF/Akt/mTOR signaling pathway that normally stimulates protein synthesis and inhibits proteolysis will be suppressed, whereas the FoxO-controlled catabolic pathways such as ubiquitin-proteolysis and autophagy/mitophagy will be activated and dominate, resulting in muscle fiber atrophy. Recent Advances: Mitochondria occupy a central position in the regulation of both protein synthesis and degradation through several redox-sensitive pathways, including peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), mitochondrial fusion and fission proteins, mitophagy, and sirtuins. Prolonged IM downregulates PGC-1α due to AMPK (5'-AMP-activated protein kinase) and FoxO activation, thus decreasing mitochondrial biogenesis and causing oxidative damage. Decrease of mitochondrial inner membrane potential and increase of mitochondrial fission can trigger cascades of mitophagy leading to loss of mitochondrial homeostasis (mitostasis), inflammation, and apoptosis. The phenotypic outcomes of these disorders are compromised muscle function and fiber atrophy. Critical Issues: Given the molecular mechanism of the pathogenesis, it is imperative that the integrity of intracellular signaling be restored to prevent the deterioration. So far, overexpression of PGC-1α via transgene and in vivo DNA transfection has been found to be effective in ameliorating mitostasis and reduces IM-induced muscle atrophy. Nutritional supplementation of select amino acids and phytochemicals also provides mechanistic and practical insights into the prevention of muscle disuse atrophy. Future Directions: In light of the importance of mitochondria in regulating the various critical signaling pathways, future work should focus on exploring new epigenetic strategies to restore mitostasis and redox balance.

EGCG ameliorates neuronal and behavioral defects by remodeling gut microbiota and TotM expression in Drosophila models of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease. Eigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, is known to exert a beneficial effect on PD patients. Although some mechanisms were suggested to underlie this intervention, it remains unknown if the EGCG-mediated protection was achieved by remodeling gut microbiota. In the present study, 0.1 mM or 0.5 mM EGCG was administered to the Drosophila melanogaster with PINK1 (PTEN induced putative kinase 1) mutations, a prototype PD model, and their behavioral performances, as well as neuronal/mitochondrial morphology (only for 0.5 mM EGCG treatment) were determined. According to the results, the mutant PINK1^B9 flies exhibited dopaminergic, survival, and behavioral deficits, which were rescued by EGCG supplementation. Meanwhile, EGCG resulted in profound changes in gut microbial compositions in PINK1^B9 flies, restoring the abundance of a set of bacteria. Notably, EGCG protection was blunted when gut microbiota was disrupted by antibiotics. We further isolated four bacterial strains from fly guts and the supplementation of individual Lactobacillus plantarum or Acetobacter pomorum strain exacerbated the neuronal and behavioral dysfunction of PD flies, which could not be rescued by EGCG. Transcriptomic analysis identified TotM as the central gene responding to EGCG or microbial manipulations. Genetic ablation of TotM blocked the recovery activity of EGCG, suggesting that EGCG-mediated protection warrants TotM. Apart from familial form, EGCG was also potent in improving sporadic PD symptoms induced by rotenone treatment, wherein gut microbiota shared regulatory roles. Together, our results suggest the relevance of the gut microbiota-TotM pathway in EGCG-mediated neuroprotection, providing insight into indirect mechanisms underlying nutritional intervention of Parkinson's disease.

Advances in physiological functions and mechanisms of (-)-epicatechin

(-)-Epicatechin (EC) is a flavanol easily obtained through the diet and is present in tea, cocoa, vegetables, fruits, and cereals. Recent studies have shown that EC protects human health and exhibits prominent anti-oxidant and anti-inflammatory activities, enhances muscle performance, improves symptoms of cardiovascular and cerebrovascular diseases, prevents diabetes, and protects the nervous system. With the development of modern medical and biotechnology research, the mechanisms of action associated with EC toward various chronic diseases are becoming more apparent, and the pharmacological development and utilization of EC has been increasingly clarified. Currently, there is no comprehensive systematic introduction to the effects of EC and its mechanisms of action. This review presents the latest research progress and the role of EC in the prevention and treatment of various chronic diseases and its protective health effects and provides a theoretical basis for future research on EC.

Effect of Epigallo-Catechin-3-Gallate on Lipid Metabolism Related Gene Expression and Yolk Fatty Acid Profiles of Laying Hens Exposed to Vanadium

As the understanding of the pathways involved in such effect are quite limited, we investigated the gene pathways that modulate lipid metabolism in layers and the fatty acid profiles of the yolk of layers that were challenged with dietary vanadium (V) and supplemented with epigallo-catechin-3-gallate (EGCG). For this purpose, a total of 120 hens were divided into four groups which were fed the following experimental diets for a period of 8 weeks: control (basal diet), V10 (control + 10 mg/kg V), EGCG130 (V10 + 130 mg/kg EGCG), and EGCG217 (V10 + 217 mg/kg EGCG). Blood total cholesterol, triglyceride, glucose, and very low-density lipoprotein-cholesterol concentration were lower in V10, EGCG130, and EGCG217 groups compared to the control group, while total cholesterol and triglyceride content in blood were lower in the EGCG217 group than in V10 group (P < 0.05). Hens consumed V10 diet had the highest triglyceride content in liver among treatments, whereas EGCG130 and EGCG217 groups had lower values when compared to those observed in the control group (P < 0.01). Dietary inclusion of V increased yolk polyunsaturated fatty acid (PUFA) and total unsaturated fatty acid (UFA) content compared to the control group (P < 0.05), whereas the addition of either 130 or 217 mg/kg EGCG in V containing diet resulted in similar yolk PUFA and UFA contents with those observed in the control group. Treatment with V alone upregulated the expression of hepatic fatty acid synthase (FAS) and sterol-regulator element-binding protein 1 (SREBP1), while EGCG downregulated FAS and SREBP1 expressions in contrast to V10 treatments (P < 0.01). Liver gene expression peroxisome proliferator-activated receptor gamma (PPARγ) was lower in the V10 than in the control group while EGCG inclusion groups upregulated their expression (P < 0.05). In conclusion, the data gathered in this study indicate that dietary V and EGCG alter the layers' lipid metabolism and fat deposition pattern in egg yolk, which might be associated with their modulatory effect on lipogenesis-related gene (FAS, SREBP1, and PPARγ) expression.

Pharmacological properties of Rheum turkestanicum Janisch

Medicinal herbs have been increasingly used worldwide for diseases prevention and treatment. Rheum turkestanicum Janisch. is a perennial shrub of the Polygonaceae family. Genus Rheum includes more than 60 species growing around the world which are used in foods and traditional medicines. R. turkestanicum is believed to be able to improve different kinds of disorders including diabetes, hypertension, jaundice and cancer. In recent years, this medicinal plant has been a subject of many experimental studies to document its health-beneficial properties. These studies have revealed antidiabetic, anticancer, nephroprotective, cardioprotective, and hepatoprotective properties of R. turkestanicum. The presence of flavonoids (e.g. epicatechin and quercetin) and anthraquinones (e.g. chrysophanol, physcion, and emodin) in R. turkestanicum justifies its health-beneficial effects. Nevertheless, possible therapeutic applications and safety of this plant still need to be elucidated in further clinical studies.

Targeting pro-senescence mitogen activated protein kinase (Mapk) enzymes with bioactive natural compounds

Aging is a multifactorial universal process characterized by a gradual decrease in physiological and biochemical functions. Given that life expectancy is on the rise, a better understanding of molecular mechanisms of the aging process is necessary in order to develop anti-aging interventions. Uncontrolled cellular senescence promotes persistent inflammation and accelerates the aging process by decreasing tissue renewal, repair and regeneration. Senescence of immune cells, immunesenescence, is another hallmark of aging. Targeting pro-senescent enzymes increases survival and therefore the lifespan. Although the upregulation of Mitogen Activated Protein Kinases (MAPK) enzymes in aging is still controversial, increasing evidence shows that dysregulation of those enzymes are associated with biological processes that contribute to aging such as irreversible senescence. In this manuscript components of the MAPK pathway will be summarized, including extracellular signal-regulated kinase 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38, as well as natural flavonoids, phenolic and diterpenoids with anti-senescence activity that shows positive effects on longevity and MAPK inhibition. Although more studies using additional aging models are needed, we suggest that these selected natural bioactive compounds that regulate MAPK enzymes and reduce senescent cells can be potentially used to improve longevity and prevent/treat age-related diseases.