Herbal supplement extends life span under some environmental conditions and boosts stress resistance

Ashwagandha- Withania somnifera (L.) Dunal as a multipotent neuroprotective remedy for genetically induced motor dysfunction and cellular toxicity in human neurodegenerative disease models of Drosophila

ETHNOPHARMACOLOGICAL RELEVANCE

Ashwagandha-Withania somnifera (L.) Dunal, well known for its multipotent therapeutic properties has been used in Ayurveda for 3000 years. The plant with more than 50 active phytoconstituents is recognised for its anti-cancerous, anti-diabetic, anti-inflammatory, anti-microbial, and neurotherapeutic properties demonstrated in in vitro studies and chemically induced rodent models. Genetically targeted Parkinson's, Alzheimer's and other neurodegenerative disease models have been created in Drosophila and have been used to get mechanistic insight into the in vivo cellular events, and genetic pathways that underlie respective neurodegenerative condition. But hitherto, there aren't enough attempts made to capitalize the genetic potential of these disease models to validate the therapeutic efficacy of different reagents used in traditional medicine, in the context of specific disease-causing genetic mutations.

AIM OF THE STUDY

Drugs discovered using in vitro platforms might fail in several instances of clinical trials because of the genetic heterogeneity and variability in the physiological context found among the patients. Drosophila by virtue of its genetically regulated experimental potential forms an ideal in vivo model to validate the candidate reagents discovered in in vitro screens for their efficacy under specific genetic situations. Here we have used genetically induced α-synucleinopathy and tauopathy transgenic fly models to study the efficacy of Ashwagandha treatment, assessing cellular and behavioural parameters.

METHODS

We have expressed the disease-causing human gene mutations in specific cell types of Drosophila using GAL4/UAS targeted expression system to create disease models. Human α-synuclein mutant (A30P) was expressed in dopaminergic neurons using Ddc-GAL4 driver strain to induce dopaminergic neurodegeneration and assayed for motor dysfunction. Human TauE14, mutant protein was expressed in photoreceptor neurons using GMR-GAL4 driver to induce photoreceptor degeneration. Microtubular destability and mitotic arrest in the dividing photoreceptor precursor cells were studied using αPH3 antibody. Lysosomal dysregulation caused necrotic black spots were induced by TauE14 with GMR-GAL4 driver, in a white mutant background. These flies mimicking neurodegenerative conditions were supplemented with different concentrations of Ashwagandha aqueous root extract mixed with regular fly food. The treated flies were analysed for cellular and behaviour parameters.

RESULTS

Lifespan assay shows that, Ashwagandha-root extract imparts an extended lifespan in male Drosophila flies which are intrinsically less stress resistant. Motor dysfunction caused due to human α-synuclein mutant protein expressed in dopaminergic neurons is greatly brought down. Further, Ashwagandha extract treatment significantly reduces TauE14 induced microtubular destability, mitotic arrest and neuronal death in photoreceptor neurons. Our experiment with tauopathy model in white mutant background exemplify that, Ashwagandha-root extract treatment can bring down lysosomal dysregulation induced necrosis of photoreceptor neurons.

CONCLUSION

We have carried out a multifaceted study which elucidates that Ashwagandha can serve as a comprehensive, phytotherapeutic formulation to combat neurodegeneration, targeting multiple causative genetically defective conditions.

Toxicity Assessment of Curculigo orchioides Leaf Extract Using Drosophila melanogaster: A Preliminary Study

Curculigo orchioides is used in Indian and Chinese traditional medicinal systems for various health benefits. However, its toxicological effects are mostly unknown. This study assesses the potential toxicity of aqueous leaf (A.L.) extract of C. orchioides using Drosophila melanogaster as an experimental model. Preliminary phytochemical tests were followed by the Fourier transform infrared (FTIR) tests to identify the functional group in the A.L. extract of C. orchioides. Drosophila larvae/adults were exposed to varying concentrations of C. orchioides A.L. extract through diet, and developmental, lifespan, reproduction, and locomotory behaviour assays were carried out to assess the C. orchioides toxicity at organismal levels. The cellular toxicity of A.L. extract was examined by analysing the expression of heat shock protein (hsps), reactive oxygen species (ROS) levels, and cell death. The FTIR analysis showed the presence of functional groups indicating the presence of secondary metabolites like saponins, phenolics, and alkaloids. Exposure to A.L. extract during development resulted in reduced emergence and wing malformations in the emerged fly. Furthermore, a significant reduction in reproductive performance and the organism's lifespan was observed when adult flies were exposed to A.L. extract. This study indicates the adverse effect of C. orchioides A.L. extract on Drosophila and raises concerns about the practice of indiscriminate therapeutic use of plant extracts.

Traditional tonifying polyherbal infusion, Jatu-Phala-Tiga, exerts antioxidant activities and extends lifespan of Caenorhabditis elegans

Background

The imbalance between the generation of free radicals and natural cellular antioxidant defenses, known as oxidative stress, can cause oxidation of biomolecules and further contribute to aging-associated diseases. The purpose of this study was to evaluate the antioxidant capacities of Thai traditional tonifying preparation, Jatu-Phala-Tiga (JPT) and its herbal ingredients consisting of Phyllanthus emblica, Terminalia arjuna, Terminalia chebula, and Terminalia bellirica and further assess its effect on longevity.

Method

Antioxidant activities of various extracts obtained from JPT and its herbal components were carried out using well-established methods including metal chelating, free radical scavenging, and ferric reducing antioxidant power assays. Qualitative analysis of the chemical composition from JPT water extract was done by high-performance liquid chromatography tandem with electrospray ionisation mass spectrometry. The effect of JPT water extract on the lifespan of Caenorhabditis elegans were additionally described.

Results

Among the extracts, JPT water extract exerted remarkable antioxidant activities as compared to the extracts from other solvents and individual constituting plant extract. JPT water extract was found to possess the highest metal chelating activity, with an IC₅₀ value of 1.75 ± 0.05 mg/mL. Moreover, it exhibited remarkable scavenging activities towards DPPH, ABTS, and superoxide anion radicals, with IC₅₀ values of 0.31 ± 0.02, 0.308 ± 0.004, and 0.055 ± 0.002 mg/mL, respectively. The ORAC and FRAP values of JPT water extract were 40.338 ± 2.273 μM of Trolox/μg of extract and 23.07 ± 1.84 mM FeSO₄/mg sample, respectively. Several well-known antioxidant-related compounds including amaronols, quinic acid, gallic acid, fertaric acid, kurigalin, amlaic acid, isoterchebin, chebulagic acid, ginkgolide C, chebulinic acid, ellagic acid, and rutin were found in this extract. Treatment with JPT water extract at 1 and 5 mg/mL increased C. elegans lifespan under normal growth condition (7.26 ± 0.65 vs. 10.4 0± 0.75 (p < 0.01) and 10.00 ± 0.73 (p < 0.01) days, respectively).

Conclusions

The results indicated that JPT and its herbal ingredients exhibited strong antioxidant activities, in particular the water extract of the polyherbal tonic. These findings rationalize further investigation in JPT infusion as a promising agent for anti-aging and oxidative stress prevention.

Nutrigenomics as a tool to study the impact of diet on aging and age-related diseases: the Drosophila approach

Aging is a complex phenomenon caused by the time-dependent loss of cellular homeodynamics and consequently of physiological organismal functions. This process is affected by both genetic and environmental (e.g., diet) factors, as well as by their constant interaction. Consistently, deregulation of nutrient sensing and signaling pathways is considered a hallmark of aging. Nutrigenomics is an emerging scientific discipline that studies changes induced by diet on the genome and thus it considers the intersection of three topics, namely health, diet, and genomics. Model organisms, such as the fruit fly Drosophila melanogaster, have been successfully used for in vivo modeling of higher metazoans aging and for nutrigenomic studies. Drosophila is a well-studied organism with sophisticated genetics and a fully annotated sequenced genome, in which ~ 75% of human disease-related genes have functional orthologs. Also, flies have organs/tissues that perform the equivalent functions of most mammalian organs, while discrete clusters of cells maintain insect carbohydrate homeostasis in a way similar to pancreatic cells. Herein, we discuss the mechanistic connections between nutrition and aging in Drosophila, and how this model organism can be used to study the effect of different diets (including natural products and/or their derivatives) on higher metazoans longevity.

Lithocholic Acid Improves the Survival of Drosophila Melanogaster

SCOPE

Primary bile acids are produced in the liver, whereas secondary bile acids, such as lithocholic acid (LCA), are generated by gut bacteria from primary bile acids that escape the ileal absorption. Besides their well-known function as detergents in lipid digestion, bile acids are important signaling molecules mediating effects on the host's metabolism.

METHODS AND RESULTS

Fruit flies (Drosophila melanogaster) are supplemented with 50 μmol L^-1 LCA either for 30 days or throughout their lifetime. LCA supplementation results in a significant induction of the mean (+12 days), median (+10 days), and maximum lifespan (+ 11 days) in comparison to untreated control flies. This lifespan extension is accompanied by an induction of spargel (srl), the fly homolog of mammalian PPAR-γ co-activator 1α (PGC1α). In wild-type flies, the administration of antibiotics abrogates both the LCA-mediated lifespan induction as well as the upregulation of srl.

CONCLUSION

It is shown that the secondary bile acid LCA significantly induces the mean, the median, and the maximum survival in D. melanogaster. Our data suggest that besides an upregulation of the PGC1α-homolog srl, unidentified alterations in the structure or metabolism of the gut microbiota contribute to the longevity effect mediated by LCA.

The Business of Anti-Aging Science

Age-related conditions are the leading causes of death and health-care costs. Reducing the rate of aging would have enormous medical and financial benefits. Myriad genes and pathways are known to regulate aging in model organisms, fostering a new crop of anti-aging companies. Approaches range from drug discovery efforts to big-data methods and direct-to-consumer (DTC) strategies. Challenges and pitfalls of commercialization include reliance on findings from short-lived model organisms, poor biological understanding of aging, and hurdles in performing clinical trials for aging. A large number of potential aging-associated interventions and targets exist, but given the long validation times only a small fraction can be explored for clinical applications. If even one company succeeds, however, the impact will be huge.

Longevity and aging. Mechanisms and perspectives

Longevity can mostly be determined with relative accuracy from birth and death registers when available. Aging is a multifactorial process, much more difficult to quantitate. Every measurable physiological function declines with specific speeds over a wide range. The mechanisms involved are also different, genetic factors are of importance for longevity determinations. The best-known genes involved are the Sirtuins, active at the genetic and epigenetic level. Aging is multifactorial, not "coded" in the genome. There are, however, a number of well-studied physical and biological parameters involved in aging, which can be determined and quantitated. We shall try to identify parameters affecting longevity as well as aging and suggest some reasonable predictions for the future.