Hormetic efficacy of rutin to promote longevity in Drosophila melanogaster

RUTIN, a widely consumed flavonoid, that commonly induces hormetic effects

Rutin is a flavonoid present in numerous fruits and vegetables and therefore widely consumed by humans. It is also a popular dietary supplement of 250-500 mg/day. There is considerable consumer interest in rutin due to numerous reports in the biomedical literature of its multi-system chemo-preventive properties. The present paper provides the first assessment of rutin-induced hormetic concentration/dose responses, their quantitative features and mechanistic basis, along with their biological, biomedical, clinical, and public health implications. The findings indicate that rutin-induced hormetic dose responses are widespread, being reported in numerous biological models and cell types for a wide range of endpoints. Of critical importance is that the optimal hormetic findings shown in in vitro systems are currently not achievable for human populations due to low gastrointestinal tract bioavailability. These findings have the potential to strengthen future experimental studies with rutin, particularly concerning study design parameters.

Rutin intake mitigates the injury of blue light irradiation by altering aging rates of mortality in Drosophila model

Blue light is known as one of the harmful light pollution that has complex effects on organisms. The massive use of LED lights in cities has greatly increased the frequency of human exposure to blue light, and therefore the hazards of blue light are receiving widespread attention. In our study, Drosophila was used as the model organism to explore the ability of the flavonoid rutin to resist blue light damage under the intensity of 3000 Lux. Siler model analysis was performed. Our results showed sex-specific pattern of rutin as an effective antioxidant. Rutin could help female flies to reduce the initial adult mortality and male flies to slow the increase of adult mortality under blue light irradiation, thus prolonging their average lifespan. Furthermore, after the intake of rutin, the locomotor activity of Drosophila under blue light irradiation was significantly increased, and the total sleep time was significantly decreased. In summary, our results provide preliminary support for exploring the mechanism of rutin against blue light damage.

Polyphenols as Potential Geroprotectors

Significance: Currently, a large amount of evidence of beneficial effects of diets enriched with polyphenols on various aspects of health has been accumulated. These phytochemicals have a geroprotective potential slowing down the pathological processes associated with aging and ensuring longevity. In this study, a comprehensive analysis was conducted to determine the adherence of individual polyphenols to geroprotector criteria. Data from experimental models, clinical trials, and epidemiological studies were analyzed. Recent Advances: Sixty-two polyphenols have been described to increase the life span and improve biomarkers of aging in animal models. They act via evolutionarily conserved molecular mechanisms, including hormesis and maintenance of redox homeostasis, epigenetic regulation, response to cellular damage, metabolic control, and anti-inflammatory and senolytic activity. Epidemiological and clinical studies suggest that certain polyphenols have a potential for prevention and treatment of various diseases, including cancer, metabolic disorders, and cardiovascular conditions in humans. Critical Issues: Among the reviewed phytochemicals, chlorogenic acid, quercetin, epicatechin, genistein, resveratrol, and curcumin were identified as compounds with the highest geroprotective potential. However, there is a lack of unambiguous information on the effectiveness and safety of polyphenols for increasing health span, preventing and treating aging-associated diseases in humans. Future Directions: Further research is needed to fully understand the effects of polyphenols considering their long-term consumption, metabolic modification and bioavailability, complex interactions between different groups of polyphenols and with other phytochemicals, as well as their effects on individuals with different health status. Antioxid. Redox Signal. 40, 564-593.

Hormesis determines lifespan

This paper addresses how long lifespan can be extended via multiple interventions, such as dietary supplements [e.g., curcumin, resveratrol, sulforaphane, complex phytochemical mixtures (e.g., Moringa, Rhodiola)], pharmaceutical agents (e.g., metformin), caloric restriction, intermittent fasting, exercise and other activities. This evaluation was framed within the context of hormesis, a biphasic dose response with specific quantitative features describing the limits of biological/phenotypic plasticity for integrative biological endpoints (e.g., cell proliferation, memory, fecundity, growth, tissue repair, stem cell population expansion/differentiation, longevity). Evaluation of several hundred lifespan extending agents using yeast, nematode (Caenorhabditis elegans), multiple insect and other invertebrate and vertebrate models (e.g., fish, rodents), revealed they responded in a manner [average (mean/median) and maximum lifespans] consistent with the quantitative features [i.e., 30-60% greater at maximum (Hormesis Rule)] of the hormetic dose response. These lifespan extension features were independent of biological model, inducing agent, endpoints measured and mechanism. These findings indicate that hormesis describes the capacity to extend life via numerous agents and activities and that the magnitude of lifespan extension is modest, in the percentage, not fold, range. These findings have important implications for human aging, genetic diseases/environmental stresses and lifespan extension, as well as public health practices and long-term societal resource planning.

Review of molecular and biochemical responses during stress induced stimulation and hormesis in insects

The biphasic hormetic response to stress, defined by low-dose stimulation and high-dose inhibition is frequently observed in insects. Various molecular and biochemical responses associated with hormesis in insects have been reported in many studies, but no synthesis of all these findings has been undertaken. We conducted a systematic literature review, analyzing papers demonstrating phenotypic stimulatory effect(s) following exposure to stress where molecular or biochemical response(s) were also examined. Responses observed included stimulation of reproduction, survival and longevity, growth and development, and tolerance to temperature, chemical, or starvation and desiccation, in response to stressors including pesticides, oxidative stress, temperature, crowding and starvation, and radiation. Phenotypic stimulation ranged from <25% increased above controls to >100%. Reproductive stimulation was frequently <25% increased above controls, while stimulated temperature tolerance was frequently >100% increased. Molecular and biochemical responses had obvious direct connections to phenotypic responses in many cases, although not in all instances. Increased expression of heat shock proteins occurred in association with stimulated temperature tolerance, and increased expression of detoxification genes with stimulated pesticide or chemical tolerance, but also stimulated reproduction. Changes in the expression or activity of antioxidants were frequently associated with stimulation of longevity and reproduction. Stress induced changes in vitellogenin and juvenile hormone and genes in the IIS/TOR signalling pathway - which are directly responsible for regulating growth, development, and reproduction - were also reported. Our analysis showed that coordination of expression of genes or proteins associated with protection from oxidative stress and DNA and protein damage is important in the hormetic responses of insects.

XENOHORMESIS UNDERLYES THE ANTI-AGING AND HEALTHY PROPERTIES OF OLIVE POLYPHENOLS

The paper provides a comprehensive and foundational mechanistic framework of hormesis that establishes its centrality in medicine and public health. This hormetic framework is applied to the assessment of olive polyphenols with respect to their capacity to slow the onset and reduce the magnitude of a wide range of age-related disorders and neurodegenerative diseases, including Alzheimer's Disease and Parkinson's Disease. It is proposed that olive polyphenol-induced anti-inflammatory protective effects are mediated in large part via the activation of AMPK and the upregulation of Nrf2 pathway. Consistently, herein we also review the importance of the modulation of Nrf2-related stress responsive vitagenes by olive polyphenols, which at low concentration according to the hormesis theory activates this neuroprotective cascade to preserve brain health and its potential use in the prevention and therapy against aging and age-related cognitive disorders in humans.

Curcuma longa L. Prevents the Loss of β-Tubulin in the Brain and Maintains Healthy Aging in Drosophila melanogaster

Loss of tubulin is associated with neurodegeneration and brain aging. Turmeric (Curcuma longa L.) has frequently been employed as a spice in curry and traditional medications in the Indian subcontinent to attain longevity and better cognitive performance. We aimed to evaluate the unelucidated mechanism of how turmeric protects the brain to be an anti-aging agent. D. melanogaster was cultured on a regular diet and turmeric-supplemented diet. β-tubulin level and physiological traits including survivability, locomotor activity, fertility, tolerance to oxidative stress, and eye health were analyzed. Turmeric showed a hormetic effect, and 0.5% turmeric was the optimal dose in preventing aging. β-tubulin protein level was decreased in the brain of D. melanogaster upon aging, while a 0.5% turmeric-supplemented diet predominantly prevented this aging-induced loss of β-tubulin and degeneration of physiological traits as well as improved β-tubulin synthesis in the brain of D. melanogaster early to mid-age. The higher concentration (≥ 1%) of turmeric-supplemented diet decreased the β-tubulin level and degenerated many of the physiological traits of D. melanogaster. The turmeric concentration-dependent increase and decrease of β-tubulin level were consistent with the increment and decrement data obtained from the evaluated physiological traits. This correlation demonstrated that turmeric targets β-tubulin and has both beneficial and detrimental effects that depend on the concentration of turmeric. The findings of this study concluded that an optimal dosage of turmeric could maintain a healthy neuron and thus healthy aging, by preventing the loss and increasing the level of β-tubulin in the brain.

A promising discovery of anti-aging chemical conjugate derived from lipoic acid and sesamol established in Drosophila melanogaster

Phytonutrients, lipoic acid and sesamol, were chemically combined to yield medically important lipoic acid-sesamol conjugate (LSC). NMR and LC-MS/MS techniques were used to determine the chemical structure of LSC. The...

Pterocarpus marsupium extract extends replicative lifespan in budding yeast

As the molecular mechanisms of biological aging become better understood, there is growing interest in identifying interventions that target those mechanisms to promote extended health and longevity. The budding yeast Saccharomyces cerevisiae has served as a premier model organism for identifying genetic and molecular factors that modulate cellular aging and is a powerful system in which to evaluate candidate longevity interventions. Here we screened a collection of natural products and natural product mixtures for effects on the growth rate, mTOR-mediated growth inhibition, and replicative lifespan. No mTOR inhibitory activity was detected, but several of the treatments affected growth rate and lifespan. The strongest lifespan shortening effects were observed for green tea extract and berberine. The most robust lifespan extension was detected from an extract of Pterocarpus marsupium and another mixture containing Pterocarpus marsupium extract. These findings illustrate the utility of the yeast system for longevity intervention discovery and identify Pterocarpus marsupium extract as a potentially fruitful longevity intervention for testing in higher eukaryotes.

Random forest classification for predicting lifespan-extending chemical compounds

Ageing is a major risk factor for many conditions including cancer, cardiovascular and neurodegenerative diseases. Pharmaceutical interventions that slow down ageing and delay the onset of age-related diseases are a growing research area. The aim of this study was to build a machine learning model based on the data of the DrugAge database to predict whether a chemical compound will extend the lifespan of Caenorhabditis elegans. Five predictive models were built using the random forest algorithm with molecular fingerprints and/or molecular descriptors as features. The best performing classifier, built using molecular descriptors, achieved an area under the curve score (AUC) of 0.815 for classifying the compounds in the test set. The features of the model were ranked using the Gini importance measure of the random forest algorithm. The top 30 features included descriptors related to atom and bond counts, topological and partial charge properties. The model was applied to predict the class of compounds in an external database, consisting of 1738 small-molecules. The chemical compounds of the screening database with a predictive probability of ≥ 0.80 for increasing the lifespan of Caenorhabditis elegans were broadly separated into (1) flavonoids, (2) fatty acids and conjugates, and (3) organooxygen compounds.

Xanthohumol prolongs lifespan and decreases stress-induced mortality in Drosophila melanogaster

Aging is a significant risk factor that links to the genesis of human diseases. The capacity to scavenge free radicals and adapt to various stresses is essential for expanding living organisms' lifespan. The evidences on the promotion of longevity by dietary supplementation are growing. Drosophila or fruit fly is one of the most effective models for the evaluation of anti-aging compounds. Xanthohumol (XN) is a potential bioactive substance for the prevention and treatment of many diseases. The previous studies have reported its potent activities as antioxidant, anticancer, anti-inflammatory, antiviral, antibacterial antiplasmodial, and antiobesity. In this study, the effect of XN supplementation on the lifespan extension was investigated in Drosophila melanogaster. The effects of XN on the improvement of the recovery from cold and heat shock, the resistance to starvation stress, and free radical-induced oxidative stress in XN-treated flies were also evaluated. Results showed that supplementation with XN at 0.5 mg/mL diet extended the mean lifespan by 14.89%. This was consistent with a significant improvement of locomotor activity of the Drosophila fed with an XN-mixed diet compared with those fed with a control diet. XN supplementation significantly increased the antioxidant enzyme activities at both 25 and 40 days. Drosophila treated with XN exhibited increased survival after exposure to hydrogen peroxide and paraquat. Finally, XN supplementation improved the recovery from cold and heat shock, the resistance to starvation stress, and acetic acid-induced stress. The present study shows that dietary supplementation with XN revealed the longevity effect and ameliorated stress-induced mortality in Drosophila.

Antioxidant and antiaging effect of traditional Thai rejuvenation medicines in Caenorhabditis elegans

OBJECTIVE

This study explored the rejuvenation mechanisms of Thai polyherbal medicines using different approaches, including in vitro methods, as well as a well-defined nematode model, Caenorhabditis elegans.

METHODS

THP-R-SR012 decoction was selected from 23 polyherbal medicines, based on metal-chelating and chain-breaking antioxidant capacities. The influences of this extract on the survival and some stress biomarkers of C. elegans under paraquat-induced oxidative stress were evaluated. Furthermore, lifespan analysis and levels of lipofuscin accumulation were examined in senescent nematodes. The phytochemical profile of THP-R-SR012 was analyzed.

RESULTS

Supplementation with THP-R-SR012 decoction significantly increased the mean lifespan and reduced the oxidative damage to C. elegans under oxidative stress conditions. Further, THP-R-SR012 supplementation slightly influenced the lifespan and the level of lipofuscin accumulation during adulthood. Antioxidant-related phytochemical constituents of THP-R-SR012 decoction were rutin, naringenin, 3,4-dihydroxybenzoic acid, gallic acid, glycyrrhizic acid, demethoxycurcumin and 18α-glycyrrhetinic acid.

CONCLUSION

The antioxidant potential of THP-R-SR012 was due to its scavenging properties, its enhancement of antioxidant-related enzyme activities, and the presence of the antioxidant-related compound. These results support the traditional use of THP-R-SR012 decoction as a tonic for nourishing and strengthening the whole body.

Sodium rutin extends lifespan and health span in mice including positive impacts on liver health

BACKGROUND AND PURPOSE

Ageing is associated with progressive metabolic dysregulation. Rutin is a metabolic regulator with a poor solubility. Using soluble sodium rutin we investigating the effect and mechanisms of rutin in ageing process.

EXPERIMENTAL APPROACH

Wild type male mice were treated with or without sodium rutin ( 0.2 mg·ml^-1 in drinking water from 8-month-old until end of life. Kaplan-Meier survival curve was used for lifespan assay, ageing-related histopathology analysis and metabolic analysis were performed to determine the effects of chronic sodium rutin on the longevity. Serological test, liver tissue metabolomics and transcriptomics were used for liver function assay. SiRNA knockdown Angptl8 and autophagy flux assay in HepG2 cell lines explored the mechanism through which sodium rutin might impact the function of hepatocyte.

KEY RESULTS

Sodium rutin treatment extends the lifespan of mice by 10%. Sodium rutin supplementation alleviates ageing-related pathological changes and promotes behaviour performance in ageing mice. Sodium rutin supplementation altered the whole-body metabolism in mice, which exhibited increased energy expenditure and lower respiratory quotient. Transcriptomics analysis showed that Sodium rutin affected the expression of metabolic genes. Metabolomics analysis showed that Sodium rutin reduced liver steatosis through increased lipid β-oxidation. Sodium rutin treatment increased the autophagy level both in vivo and in vitro. The inhibition of autophagy partially abolished the sodium rutin-mediated effect on lipolysis in HepG2 cells.

CONCLUSION AND IMPLICATIONS

Sodium rutin treatment extends the lifespan and health span of mice with beneficial effects on metabolism, which were achieved by enhancing the autophagy activity in hepatocytes.

Cardioprotective effects and concentration-response relationship of aminoalcohol-diterpenoid alkaloids from Aconitum carmichaelii

Fuzi, a well-known traditional Chinese medicine developed from the lateral roots of Aconitum carmichaelii Debx., has been widely used for the treatment of heart failure. In order to search for active compounds from Fuzi, a phytochemical study was performed, which resulted in the isolation of 14 aminoalcohol-diterpenoid alkaloids, including one new compound (1). Their cardioprotective effects against doxorubicin-induced toxicity in H9c2 cells were evaluated. All of the alkaloids showed cardioprotective effects in a nonmonotonic concentration-response manner, with the maximum protection rates ranging from 17.96 ± 2.93% to 98.31 ± 0.35%. Compound 5 exhibited the most potent cardioprotective activity. Taking the maximum protection rate as an indicator, the preliminary structure-activity relationship analysis indicated that the substitutions of C-1, C-13, C-15, C-16, and N and the configurations of OMe-6 and OH-15 are important structural features for the cardioprotective activities of the aminoalcohol-diterpenoid alkaloids.

Biphasic Dose-Response of Components From Coptis chinensis on Feeding and Detoxification Enzymes of Spodoptera litura Larvae

Due to long-term coevolution, secondary metabolites present in plants apparently function as chemical defense against insect feeding, while various detoxification enzymes in insects are adaptively induced as a prosurvival mechanism. Coptis chinensis, a medicinal plant used in traditional Chinese medicine for a thousand years, was found to be less prey to insects in our earlier field observations. Herein, 4 crude extracts obtained from sequential partition of aqueous extract of Rhizoma coptidis with petroleum ether, ethyl acetate, and n-butanol exhibited antifeedant activity against Spodoptera litura (Fabricius) larvae at high doses and inducing activity at low doses. Furthermore, a similar biphasic dose–response of the antifeedant activity against S litura larvae was also observed for jateorhizine, palmatine, and obakunone in Coptis chinensis. Notably, the enzyme activities of glutathione-S-transferase and carboxyl esterase in S litura larvae affected by the different components (jateorhizine, palmatine, obakunone, berberine, and coptisine) of C chinensis also showed a biphasic dose–response with an increasing trend at low doses and a decreasing trend at high doses. Together, our study suggests that the components of C chinensis may play a chemical defensive role against S litura larvae in a hormetic manner.

Longevity-promoting efficacies of rutin in high fat diet fed Drosophila melanogaster

Composition of diet significantly impacts lifespan in Drosophila melanogaster. Diet-composition becomes even more crucial while assessing a phytocompound for probable pro-longevity effects in flies. Rutin is a flavonol glycoside present in apple, buckwheat, black tea and green tea. Our previous study had reported hormetic efficacy of rutin to improve longevity and other physiological parameters in Drosophila melanogaster fed with standard diet. This study aimed to understand whether rutin could exhibit similar longevity promoting effects in flies fed with a high fat diet (HFD). In this study, wild type Canton-S males and females were reared on high fat diet (HFD) treated with or without rutin at different doses (100-800 µM) and assessed for survival, food intake, fecundity, locomotion, development, resistance to various forms of stresses and relative mRNA expression of specific genes associated with ageing, namely dFoxO, MnSod, Cat, dTsc1, dTsc2, Thor, dAtg1, dAtg5, dAtg7 and dTor. Rutin at only 400 µM significantly improved survival in males fed with HFD; while at 200 µM and 400 µM it significantly improved survival in females. Doses beyond 400 µM proved detrimental for both sexes. Rutin at 200 µM and 400 µM significantly reduced average food intake in both males and females fed with HFD. A significant reduction in number of eggs laid per female per day was observed in females treated with rutin at 400 µM. Rutin at 200 µM and 400 µM significantly improved climbing efficiency in males and females. A significant reduction in eclosion time was observed in larvae fed with HFD and treated with rutin at 400 µM. Rutin at 400 µM significantly improved resistance of males and females to different stresses namely heat shock, cold shock and starvation stresses. Interestingly, rutin at 400 µM significantly reduced survival of males and females exposed to oxidative stress. In males fed with HFD, rutin at 200 µM showed significantly increased relative expression of dFoxo, MnSod, Cat, dAtg1, dAtg5 and dAtg7; at 400 µM it significantly increased the relative expression of dFoxO, MnSod, Cat, dTsc1, dTsc2, Thor, dAtg1, dAtg5, dAtg7 while decreasing relative expression of dTor. Thus, data from this study collectively showed that rutin at 400 µM and to an extent 200 µM positively impacted lifespan and modulated other physiological parameters in males and females fed with HFD.

Biphasic Dose-Response Induced by Phytochemicals: Experimental Evidence

Many phytochemicals demonstrate nonmonotonic dose/concentration-response termed biphasic dose-response and are considered to be hormetic compounds, i.e., they induce biologically opposite effects at different doses. In numerous articles the hormetic nature of phytochemicals is declared, however, no experimental evidence is provided. Our aim was to present the overview of the reports in which phytochemical-induced biphasic dose-response is experimentally proven. Hence, we included in the current review only articles in which the reversal of response between low and high doses/concentrations of phytochemicals for a single endpoint was documented. The majority of data on biphasic dose-response have been found for phytoestrogens; other reports described these types of effects for resveratrol, sulforaphane, and natural compounds from various chemical classes such as isoquinoline alkaloid berberine, polyacetylenes falcarinol and falcarindiol, prenylated pterocarpan glyceollin1, naphthoquinones plumbagin and naphazarin, and panaxatriol saponins. The prevailing part of the studies presented in the current review was performed on cell cultures. The most common endpoint tested was a proliferation of tumor and non-cancerous cells. Very few experiments demonstrating biphasic dose-response induced by phytochemicals were carried out on animal models. Data on the biphasic dose-response of various endpoints to phytochemicals may have a potential therapeutic or preventive implication.

Ellagic acid prolongs the lifespan of Drosophila melanogaster

Wild-type Canton-S flies of Drosophila melanogaster were treated with ellagic acid at 100 μM and 200 μM concentrations. Longevity assay showed male flies fed with 200 μM ellagic acid displayed longer mean lifespan and maximum lifespan than control flies. Female flies fed with 200 μM ellagic acid laid less number of eggs than control. The eclosion time was less in female flies fed with 200 μM ellagic acid. Ellagic acid fed female flies performed better than male flies and control flies for heat shock tolerance and starvation stress. Male flies treated with 100 μM ellagic acid recovered faster from cold shock compared with control flies. Male and female flies treated with ellagic acid displayed increased survival following exposure to 5% hydrogen peroxide. Gene expression studies displayed upregulated expressions of CAT, dFOXO, ATG1, and SOD2 in ellagic acid-treated male flies, and upregulated expressions of dFOXO, CAT, and SOD2 in ellagic acid-treated female flies. Results from these studies show the pro-longevity effect of ellagic acid on Drosophila melanogaster.

Larval crowding results in hormesis-like effects on longevity in Drosophila: timing of eclosion as a model

There is increasing evidence that stress during development can affect adult-life health status and longevity. In the present study, we examined life span (LS), fly weight, fecundity and expression levels of longevity-associated genes (Hsp70, InR, dSir2, dTOR and dFOXO) in adult Drosophila melanogaster flies reared in normal [low density (LD), ~ 300-400 eggs per jar] or crowded [high density (HD), more than 3000 eggs per jar] conditions by using the order (day) of emergence as an index of the developmental duration (HD1-5 groups). Developmental time showed a significant trend to increase while weight showed a significant trend to decrease with increasing the timing of emergence. In both males and females eclosed during first 2 days in HD conditions (HD1 and HD2 groups), both mean and maximum LSs were significantly increased in comparison to LD group. In males, mean LS was increased by 24.0% and 23.5% in HD1 and HD2 groups, respectively. In females, corresponding increments in mean LS were 23.8% (HD1 group) and 29.3% (HD2 group). In HD groups, a strong negative association with developmental time has been found for both male and female mean and male maximum LSs; no association with growth rate was observed for female maximum LS. The female reproductive activity (fecundity) tended to decrease with subsequent days of eclosion. In HD groups, the levels of expression of all studied longevity-associated genes tended to increase with the timing of eclosion in males; no differences were observed in females. On the basis of findings obtained, it can be assumed that the development in conditions of larval overpopulation (if not too extended) could trigger hormetic response thereby extending the longevity. Further studies are, however, needed to confirm this assumption.