Differential effects of phytotherapic preparations in the hSOD1 Drosophila melanogaster model of ALS

Pan-neuronal expression of human mutant SOD1 in Drosophila impairs survival and motor performance, induces early neuroinflammation and chromosome aberrations

Several mutations in the SOD1 gene encoding for the antioxidant enzyme Superoxide Dismutase 1, are associated with amyotrophic lateral sclerosis, a rare and devastating disease characterized by motor neuron degeneration and patients' death within 2-5 years from diagnosis. Motor neuron loss and related symptomatology manifest mostly in adult life and, to date, there is still a gap of knowledge on the precise cellular and molecular events preceding neurodegeneration. To deepen our awareness of the early phases of the disease, we leveraged two Drosophila melanogaster models pan-neuronally expressing either the mutation A4V or G85R of the human gene SOD1 (hSOD1A4V or hSOD1G85R). We demonstrate that pan-neuronal expression of the hSOD1A4V or hSOD1G85R pathogenic construct impairs survival and motor performance in transgenic flies. Moreover, protein and transcript analysis on fly heads indicates that mutant hSOD1 induction stimulates the glial marker Repo, up-regulates the IMD/Toll immune pathways through antimicrobial peptides and interferes with oxidative metabolism. Finally, cytological analysis of larval brains demonstrates hSOD1-induced chromosome aberrations. Of note, these parameters are found modulated in a timeframe when neurodegeneration is not detected. The novelty of our work is twofold: we have expressed for the first time hSOD1 mutations in all neurons of Drosophila and confirmed some ALS-related pathological phenotypes in these flies, confirming the power of SOD1 mutations in generating ALS-like phenotypes. Moreover, we have related SOD1 pathogenesis to chromosome aberrations and antimicrobial peptides up-regulation. These findings were unexplored in the SOD1-ALS field.

Emerging Vistas for the Nutraceutical Withania somnifera in Inflammaging

Inflammaging, a coexistence of inflammation and aging, is a persistent, systemic, low-grade inflammation seen in the geriatric population. Various natural compounds have been greatly explored for their potential role in preventing and treating inflammaging. Withania somnifera has been used for thousands of years in traditional medicine as a nutraceutical for its numerous health benefits including regenerative and adaptogenic effects. Recent preclinical and clinical studies on the role of Withania somnifera and its active compounds in treating aging, inflammation, and oxidative stress have shown promise for its use in healthy aging. We discuss the chemistry of Withania somnifera, the etiology of inflammaging and the protective role(s) of Withania somnifera in inflammaging in key organ systems including brain, lung, kidney, and liver as well as the mechanistic underpinning of these effects. Furthermore, we elucidate the beneficial effects of Withania somnifera in oxidative stress/DNA damage, immunomodulation, COVID-19, and the microbiome. We also delineate a putative protein-protein interaction network of key biomarkers modulated by Withania somnifera in inflammaging. In addition, we review the safety/potential toxicity of Withania somnifera as well as global clinical trials on Withania somnifera. Taken together, this is a synthetic review on the beneficial effects of Withania somnifera in inflammaging and highlights the potential of Withania somnifera in improving the health-related quality of life (HRQoL) in the aging population worldwide.

ALSUntangled #74: Withania Somnifera (Ashwagandha)

ALSUntangled reviews alternative and off-label treatments on behalf of people with ALS (PALS) who ask about them. Here, we review withania somnifera (WS) commonly known as ashwagandha or winter cherry. WS has plausible mechanisms for slowing ALS progression because of its effects on inflammation, oxidative stress, autophagy, mitochondrial function, and apoptosis. Preclinical trials demonstrate that WS slows disease progression in multiple different animal models of ALS. Of the five individuals we found who described using WS for their ALS, two individuals reported moderate benefit while none reported experiencing any significant side effects. There is currently one clinical trial using WS to treat PALS; the results are not yet published. There are no serious side effects associated with WS and the associated cost of this treatment is low. Based on the above information, WS appears to us to be a good candidate for future ALS trials.

Modeling Myotonic Dystrophy Type 2 Using Drosophila melanogaster

Myotonic dystrophy 2 (DM2) is a genetic multi-systemic disease primarily affecting skeletal muscle. It is caused by CCTGn expansion in intron 1 of the CNBP gene, which encodes a zinc finger protein. DM2 disease has been successfully modeled in Drosophila melanogaster, allowing the identification and validation of new pathogenic mechanisms and potential therapeutic strategies. Here, we describe the principal tools used in Drosophila to study and dissect molecular pathways related to muscular dystrophies and summarize the main findings in DM2 pathogenesis based on DM2 Drosophila models. We also illustrate how Drosophila may be successfully used to generate a tractable animal model to identify novel genes able to affect and/or modify the pathogenic pathway and to discover new potential drugs.

Single-cell type analysis of wing premotor circuits in the ventral nerve cord of Drosophila melanogaster

To perform most behaviors, animals must send commands from higher-order processing centers in the brain to premotor circuits that reside in ganglia distinct from the brain, such as the mammalian spinal cord or insect ventral nerve cord. How these circuits are functionally organized to generate the great diversity of animal behavior remains unclear. An important first step in unraveling the organization of premotor circuits is to identify their constituent cell types and create tools to monitor and manipulate these with high specificity to assess their function. This is possible in the tractable ventral nerve cord of the fly. To generate such a toolkit, we used a combinatorial genetic technique (split-GAL4) to create 195 sparse driver lines targeting 198 individual cell types in the ventral nerve cord. These included wing and haltere motoneurons, modulatory neurons, and interneurons. Using a combination of behavioral, developmental, and anatomical analyses, we systematically characterized the cell types targeted in our collection. Taken together, the resources and results presented here form a powerful toolkit for future investigations of neural circuits and connectivity of premotor circuits while linking them to behavioral outputs.

Withania somnifera Extracts Promote Resilience against Age-Related and Stress-Induced Behavioral Phenotypes in Drosophila melanogaster; a Possible Role of Other Compounds besides Withanolides

Withania somnifera (WS) extracts have been used in traditional medicine for millennia to promote healthy aging and wellbeing. WS is now also widely used in Western countries as a nutritional supplement to extend healthspan and increase resilience against age-related changes, including sleep deficits and depression. Although human trials have supported beneficial effects of WS, the study designs have varied widely. Plant material is intrinsically complex, and extracts vary widely with the origin of the plant material and the extraction method. Commercial supplements can contain various other ingredients, and the characteristics of the study population can also be varied. To perform maximally controlled experiments, we used plant extracts analyzed for their composition and stability. We then tested these extracts in an inbred Drosophila line to minimize effects of the genetic background in a controlled environment. We found that a water extract of WS (WSAq) was most potent in improving physical fitness, while an ethanol extract (WSE) improved sleep in aged flies. Both extracts provided resilience against stress-induced behavioral changes. WSE contained higher levels of withanolides, which have been proposed to be active ingredients, than WSAq. Therefore, withanolides may mediate the sleep improvement, whereas so-far-unknown ingredients enriched in WSAq likely mediate the effects on fitness and stress-related behavior.

Metabolic Profile and Pathological Alterations in the Muscle of Patients with Early-Stage Amyotrophic Lateral Sclerosis

Diverse biomarkers and pathological alterations have been found in muscle of patients with Amyotrophic lateral sclerosis (ALS), but the relation between such alterations and dysfunction in energetic metabolism remains to be investigated. We established the metabolome of muscle and serum of ALS patients and correlated these findings with the clinical status and pathological alterations observed in the muscle. We obtained data from 20 controls and 17 ALS patients (disease duration: 9.4 ± 6.8 months). Multivariate metabolomics analysis identified a distinct serum metabolome for ALS compared to controls (p-CV-ANOVA < 0.035) and revealed an excellent discriminant profile for muscle metabolome (p-CV-ANOVA < 0.0012). Citramalate was discriminant for both muscle and serum. High lauroylcarnitine levels in muscle were associated with low Forced Vital Capacity. Transcriptomics analysis of key antioxidant enzymes showed an upregulation of SOD3 (p = 0.0017) and GLRX2(1) (p = 0.0022) in ALS muscle. Analysis of mitochondrial enzymatic activity in muscle revealed higher complex II/CS (p = 0.04) and lower LDH (p = 0.03) activity in ALS than in controls. Our study showed, for the first time, a global dysfunction in the muscle of early-stage ALS patients. Furthermore, we identified novel metabolites to be employed as biomarkers for diagnosis and prognosis of ALS patients.

Animal Models of Neurodegenerative Disease: Recent Advances in Fly Highlight Innovative Approaches to Drug Discovery

Neurodegenerative diseases represent a formidable challenge to global health. As advances in other areas of medicine grant healthy living into later decades of life, aging diseases such as Alzheimer's disease (AD) and other neurodegenerative disorders can diminish the quality of these additional years, owed largely to the lack of efficacious treatments and the absence of durable cures. Alzheimer's disease prevalence is predicted to more than double in the next 30 years, affecting nearly 15 million Americans, with AD-associated costs exceeding $1 billion by 2050. Delaying onset of AD and other neurodegenerative diseases is critical to improving the quality of life for patients and reducing the burden of disease on caregivers and healthcare systems. Significant progress has been made to model disease pathogenesis and identify points of therapeutic intervention. While some researchers have contributed to our understanding of the proteins and pathways that drive biological dysfunction in disease using in vitro and in vivo models, others have provided mathematical, biophysical, and computational technologies to identify potential therapeutic compounds using in silico modeling. The most exciting phase of the drug discovery process is now: by applying a target-directed approach that leverages the strengths of multiple techniques and validates lead hits using Drosophila as an animal model of disease, we are on the fast-track to identifying novel therapeutics to restore health to those impacted by neurodegenerative disease.

Effect of Ashwagandha Withanolides on Muscle Cell Differentiation

Withania somnifera (Ashwagandha) is used in Indian traditional medicine, Ayurveda, and is believed to have a variety of health-promoting effects. The molecular mechanisms and pathways underlying these effects have not yet been sufficiently explored. In this study, we investigated the effect of Ashwagandha extracts and their major withanolides (withaferin A and withanone) on muscle cell differentiation using C2C12 myoblasts. We found that withaferin A and withanone and Ashwagandha extracts possessing different ratios of these active ingredients have different effects on the differentiation of C2C12. Withanone and withanone-rich extracts caused stronger differentiation of myoblasts to myotubes, deaggregation of heat- and metal-stress-induced aggregated proteins, and activation of hypoxia and autophagy pathways. Of note, the Parkinson’s disease model of Drosophila that possess a neuromuscular disorder showed improvement in their flight and climbing activity, suggesting the potential of Ashwagandha withanolides for the management of muscle repair and activity.

Fly for ALS: Drosophila modeling on the route to amyotrophic lateral sclerosis modifiers

Amyotrophic lateral sclerosis (ALS) is a rare, devastating disease, causing movement impairment, respiratory failure and ultimate death. A plethora of genetic, cellular and molecular mechanisms are involved in ALS signature, although the initiating causes and progressive pathological events are far from being understood. Drosophila research has produced seminal discoveries for more than a century and has been successfully used in the past 25 years to untangle the process of ALS pathogenesis, and recognize potential markers and novel strategies for therapeutic solutions. This review will provide an updated view of several ALS modifiers validated in C9ORF72, SOD1, FUS, TDP-43 and Ataxin-2 Drosophila models. We will discuss basic and preclinical findings, illustrating recent developments and novel breakthroughs, also depicting unsettled challenges and limitations in the Drosophila-ALS field. We intend to stimulate a renewed debate on Drosophila as a screening route to identify more successful disease modifiers and neuroprotective agents.

Where and Why Modeling Amyotrophic Lateral Sclerosis

Over the years, researchers have leveraged a host of different in vivo models in order to dissect amyotrophic lateral sclerosis (ALS), a neurodegenerative/neuroinflammatory disease that is heterogeneous in its clinical presentation and is multigenic, multifactorial and non-cell autonomous. These models include both vertebrates and invertebrates such as yeast, worms, flies, zebrafish, mice, rats, guinea pigs, dogs and, more recently, non-human primates. Despite their obvious differences and peculiarities, only the concurrent and comparative analysis of these various systems will allow the untangling of the causes and mechanisms of ALS for finally obtaining new efficacious therapeutics. However, harnessing these powerful organisms poses numerous challenges. In this context, we present here an updated and comprehensive review of how eukaryotic unicellular and multicellular organisms that reproduce a few of the main clinical features of the disease have helped in ALS research to dissect the pathological pathways of the disease insurgence and progression. We describe common features as well as discrepancies among these models, highlighting new insights and emerging roles for experimental organisms in ALS.

Mitochondrial Redox Signaling Is Critical to the Normal Functioning of the Neuronal System

Mitochondrial dysfunction often leads to neurodegeneration and is considered one of the main causes of neurological disorders, such as Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and other age-related diseases. Mitochondrial dysfunction is tightly linked to oxidative stress and accumulating evidence suggests the association between oxidative stress and neurological disorders. However, there is insufficient knowledge about the role of pro-oxidative shift in cellular redox and impairment of redox-sensitive signaling in the development of neurodegenerative pathological conditions. To gain a more complete understanding of the relationship between mitochondria, redox status, and neurodegenerative disorders, we investigated the effect of mitochondrial thiol-dependent peroxidases, peroxiredoxins (Prxs), on the physiological characteristics of flies, which change with pathologies such as PD, ALS and during aging. We previously found that through their ability to sense changes in redox and regulate redox-sensitive signaling, Prxs play a critical role in maintaining global thiol homeostasis, preventing age-related apoptosis and chronic activation of the immune response. We also found that the phenotype of flies under-expressing Prxs in mitochondria shares many characteristics with the phenotype of Drosophila models of neurological disorders such as ALS, including impaired locomotor activity and compromised redox balance. Here, we expanded the study and found that under-expression of mitochondrial Prxs leads to behavioral changes associated with neural function, including locomotor ability, sleep-wake behavior, and temperature-sensitive paralysis. We also found that under-expression of mitochondrial Prxs with a motor-neuron-specific driver, D42-GAL4, was a determining factor in the development of the phenotype of shortened lifespan and impaired motor activity in flies. The results of the study suggest a causal link between mitochondrial Prx activity and the development of neurological disorders and pre-mature aging.

Differential effect of Ayurvedic nootropics on C. elegans models of Parkinson's disease

BACKGROUND

Globally, there is increased incidence of Parkinson's Disease (PD), which is the second most common age-related neurodegenerative disease. The currently available PD-therapeutics provide only symptomatic relief. Thus, there is an urgent need to devise an effective and safe treatment strategy for PD. The holistic approach of Ayurveda can be a potential effective strategy for treating PD. The integration of different medicine systems, such as modern bio-medicine and Ayurveda can be an effective strategy for treatment of complex diseases, including PD.

OBJECTIVE

This study aimed to evaluate the neuroprotective mechanism of six Ayurvedic nootropics that are commonly used to treat PD.

MATERIAL AND METHODS

Six Ayurvedic herbs, namely Mucuna pruriens (MP), Bacopa monnieri (BM), Withania somnifera (WS), Centella asiatica (CA), Sida cordifolia (SC), and Celastrus paniculatus (CP), were selected after consultation with Ayurvedic scholars and physicians. The mode of action of methanolic herbal extracts was evaluated using the Caenorhabditis elegans BZ555 and NL5901 strains, which can be used to model the two main hallmarks of PD, namely degeneration of dopaminergic neurons and aggregation of α-synuclein protein.

RESULTS

All six herbal extracts exhibited neuroprotective effect. The extracts of BM and MP exhibited maximum protection against 1-methyl-4-phenylpyridinium iodide (MPP+ iodide)-induced dopaminergic neurodegeneration in the BZ555 strain. Furthermore, the herbal extracts, except CA extract, inhibited the aggregation of heterologously expressed human α-synuclein in the NL5901 strain.

CONCLUSION

Ayurvedic herbs used in the treatment of PD exhibited differential neuroprotective and protein aggregation mitigating effects in C. elegans.

Neurodegenerative Susceptibility During Maternal Nutritional Programing: Are Central and Peripheral Innate Immune Training Relevant?

Maternal overnutrition modulates body weight, development of metabolic failure and, potentially, neurodegenerative susceptibility in the offspring. Overnutrition sets a chronic pro-inflammatory profile that integrates peripheral and central immune activation nodes, damaging neuronal physiology and survival. Innate immune cells exposed to hypercaloric diets might experience trained immunity. Here, we address the role of maternal overnutrition as a trigger for central and peripheral immune training and its contribution to neurodegeneration and the molecular nodes implicated in the Nod-like receptor protein 3 (NLRP3) inflammasome pathway leading to immune training. We propose that maternal overnutrition leads to peripheral or central immune training that favor neurodegenerative susceptibility in the offspring.

The imbalance of serotonergic circuitry impairing the crop supercontractile muscle activity and the mitochondrial morphology of PD PINK1B9Drosophila melanogaster are rescued by Mucuna pruriens

Despite its great potentiality, little attention has been paid to modelling gastrointestinal symptoms of Parkinson's disease (PD) in Drosophila melanogaster (Dm). Our previous studies on standardized Mucuna pruriens extract (Mpe) have shown usefulness in the Drosophila model of PD. In this communication, we provide new information on the effect of Mpe on basal and serotonin treated contractions in the crop (i.e., an important and essential part of the gut) in Drosophila PD mutant for PTEN-induced putative kinase 1 (PINK1^B9) gene. The effect of Mpe on PINK1^B9 supplied with standard diet to larvae and/or adults, were assayed on 10-15 days old flies. Conversely from what we observed in the wild type flies, recordings demonstrated that exogenous applications of serotonin on crop muscles of untreated PINK1^B9 affect neither the frequency nor the amplitude of the crop contraction, while the same muscle parameters are enhanced following brain injections of serotonin, thus suggesting that PINK1^B9 mutants may likely have an impairment in the serotonergic pathways. Also, the mitochondrial morphology in the crop muscles is strongly compromised, as demonstrated by the transmission electron microscopy analysis. The Mpe treatment rescued the crop muscle parameters and also the mitochondrial morphology when supplied to both larvae and adults. Overall, this study strengthens the relevance of using PINK1^B9 Dm as a translational model to study the gastrointestinal symptoms in PD and also confirms the useful employment of M. pruriens for PD treatment.

Standardized phytotherapic extracts rescue anomalous locomotion and electrophysiological responses of TDP-43 Drosophila melanogaster model of ALS

Findings from studies using animal models expressing amyotrophic lateral sclerosis (ALS) mutations in RNA-binding proteins, such as Transactive Response DNA-binding protein-43 (TDP-43), indicate that this protein, which is involved in multiple functions, including transcriptional regulation and pre-mRNA splicing, represents a key candidate in ALS development. This study focuses on characterizing, in a Drosophila genetic model of ALS (TDP-43), the effects of Mucuna pruriens (Mpe) and Withania somnifera (Wse). Electrophysiological and behavioural data in TDP-43 mutant flies revealed anomalous locomotion (i.e. impaired climbing with unexpected hyperactivity) and sleep dysregulation. These features, in agreement with previous findings with a different ALS model, were at least partially, rescued by treatment with Mpe and Wse. In addition, electrophysiological recordings from dorsal longitudinal muscle fibers and behavioral observations of TDP-43 flies exposed to the volatile anaesthetics, diethyl ether or chloroform, showed paradoxical responses, which were normalized upon Mpe or Wse treatment. Hence, given the involvement of some potassium channels in the effects of anaesthetics, our results also hint toward a possible dysregulation of some potassium channels in the ALS-TDP-43 Drosophila model, that might shed new light on future therapeutic strategies pertaining to ALS.

Neuronal Lamin regulates motor circuit integrity and controls motor function and lifespan

Neuronal aging involves a progressive decline in cognitive abilities and loss of motor function. Mutations in human Lamin genes (LMNA, LMNB1, LMNB2) lead to a wide-range of diseases including muscular dystrophy, peripheral neuropathy and progeria. Here we investigate the role of neuronal Lamin in regulating age-related phenotypes. Neuronal targeting of Lamin led to shortened lifespan, progressive impairment of motor function and loss of dopaminergic (DA) neurons within the protocerebral anterior medial (PAM) cluster in the Drosophilamelanogaster brain. Loss of neuronal Lamin caused an age-related decline in neural physiology, with slower neurotransmission and increased chance of motor circuit failure with age. Unexpectedly, Lamin-dependent decline in motor function was specific for the chemical synapses of the dorsal longitudinal muscle (DLM). Together these findings highlight a central role for Lamin dysfunction in regulating neuronal survival and motor circuit physiology during aging.