The ACE inhibitor captopril inhibits ACN-1 to control dauer formation and aging.

The renin-angiotensin-aldosterone system (RAAS) plays a well-characterized role regulating blood pressure in mammals. Pharmacological and genetic manipulation of the RAAS has been shown to extend lifespan in Caenorhabditis elegans, Drosophila and rodents, but its mechanism is not well defined. Here, we investigate the angiotensin-converting enzyme (ACE) inhibitor drug captopril, which extends lifespan in worms and mice. To investigate the mechanism, we performed a forward genetic screen for captopril-hypersensitive mutants. We identified a missense mutation that causes a partial loss of function of the daf-2 receptor tyrosine kinase gene, a powerful regulator of aging. The homologous mutation in the human insulin receptor causes Donohue syndrome, establishing these mutant worms as an invertebrate model of this disease. Captopril functions in C. elegans by inhibiting ACN-1, the worm homolog of ACE. Reducing the activity of acn-1 via captopril or RNA interference promoted dauer larvae formation, suggesting that acn-1 is a daf gene. Captopril-mediated lifespan extension was abrogated by daf-16(lf) and daf-12(lf) mutations. Our results indicate that captopril and acn-1 influence lifespan by modulating dauer formation pathways. We speculate that this represents a conserved mechanism of lifespan control.

The Potential Use of Plant Natural Products and Plant Extracts with Antioxidant Properties for the Prevention/Treatment of Neurodegenerative Diseases: In Vitro, In Vivo and Clinical Trials.

Neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease and Huntington's disease, present a major health issue and financial burden for health care systems around the world. The impact of these diseases will further increase over the next decades due to increasing life expectancies. No cure is currently available for the treatment of these conditions; only drugs, which merely alleviate the symptoms. Oxidative stress has long been associated with neurodegeneration, whether as a cause or as part of the downstream results caused by other factors. Thus, the use of antioxidants to counter cellular oxidative stress within the nervous system has been suggested as a potential treatment option for neurological disorders. Over the last decade, significant research has focused on the potential use of natural antioxidants to target oxidative stress. However, clinical trial results have lacked success for the treatment of patients with neurological disorders. The knowledge that natural extracts show other positive molecular activities in addition to antioxidant activity, however, has led to further research of natural extracts for their potential use as prevention or treatment/management of neurodegenerative diseases. This review will cover several in vitro and in vivo research studies, as well as clinical trials, and highlight the potential of natural antioxidants.

Pharmacological inhibition of acetylcholinesterase improves the locomotion defective phenotype of a SCA3 C. elegans model.

Inhibition of acetylcholinesterase (AChE) is a common used treatment option for Alzheimer's disease. However, there has been limited research on the potential use of AChE inhibitors for the treatment of Machado-Joseph disease (MJD)/Spinocerebellar Ataxia 3 (SCA3), in spite of the positive results using AChE inhibitors in patients with other inherited ataxias. MJD/SCA3, the most common form of dominant Spinocerebellar Ataxia worldwide, is caused by an expansion of the polyglutamine tract within the ataxin-3 protein, and is characterized by motor impairments. Our study shows that administration of the AChE inhibitor neostigmine is beneficial in treating the locomotion defective phenotype of a SCA3/MJD model of C. elegans and highlights the potential contribution of AChE enzymes to mutant ataxin-3-mediated toxicity.

The ACE-inhibitor drug captopril inhibits ACN-1 to control dauer formation and aging.

The renin-angiotensin-aldosterone system (RAAS) plays a well-characterized role regulating blood pressure in mammals. Pharmacological and genetic manipulation of the RAAS has been shown to extend lifespan in C. elegans , Drosophila , and rodents, but its mechanism is not well defined. Here we investigate the angiotensin-converting enzyme (ACE) inhibitor drug captopril, which extends lifespan in worms and mice. To investigate the mechanism, we performed a forward genetic screen for captopril hypersensitive mutants. We identified a missense mutation that causes a partial loss-of-function of the daf-2 receptor tyrosine kinase gene, a powerful regulator of aging. The homologous mutation in the human insulin receptor causes Donohue syndrome, establishing these mutant worms as an invertebrate model of this disease. Captopril functions in C. elegans by inhibiting ACN-1, the worm homolog of ACE. Reducing the activity of acn-1 via captopril or RNAi promoted dauer larvae formation, suggesting acn-1 is a daf gene. Captopril-mediated lifespan extension xwas abrogated by daf-16(lf) and daf-12(lf) mutations. Our results indicate that captopril and acn-1 control aging by modulating dauer formation pathways. We speculate that this represents a conserved mechanism of lifespan control. Summary Statement: Captopril and acn-1 control aging. By demonstrating they regulate dauer formation and interact with daf genes, including a new DAF-2(A261V) mutant corresponding to a human disease variant, we clarified the mechanism.

UNC-49 is a redox-sensitive GABAA receptor that regulates the mitochondrial unfolded protein response cell nonautonomously.

The γ-aminobutyric acid-mediated (GABAergic) system participates in many aspects of organismal physiology and disease, including proteostasis, neuronal dysfunction, and life-span extension. Many of these phenotypes are also regulated by reactive oxygen species (ROS), but the redox mechanisms linking the GABAergic system to these phenotypes are not well defined. Here, we report that GABAergic redox signaling cell nonautonomously activates many stress response pathways in Caenorhabditis elegans and enhances vulnerability to proteostasis disease in the absence of oxidative stress. Cell nonautonomous redox activation of the mitochondrial unfolded protein response (mitoUPR) proteostasis network requires UNC-49, a GABAA receptor that we show is activated by hydrogen peroxide. MitoUPR induction by a spinocerebellar ataxia type 3 (SCA3) C. elegans neurodegenerative disease model was similarly dependent on UNC-49 in C. elegans. These results demonstrate a multi-tissue paradigm for redox signaling in the GABAergic system that is transduced via a GABAA receptor to function in cell nonautonomous regulation of health, proteostasis, and disease.

Control of aging by the renin-angiotensin system: a review of C. elegans, Drosophila, and mammals.

The free-living, non-parasitic nematode Caenorhabditis elegans is a premier model organism for the study of aging and longevity due to its short lifespan, powerful genetic tools, and conservation of fundamental mechanisms with mammals. Approximately 70 percent of human genes have homologs in C. elegans, including many that encode proteins in pathways that influence aging. Numerous genetic pathways have been identified in C. elegans that affect lifespan, including the dietary restriction pathway, the insulin/insulin-like growth factor (IGF) signaling pathway, and the disruption of components of the mitochondrial electron transport chain. C. elegans is also a powerful system for performing drug screens, and many lifespan-extending compounds have been reported; notably, several FDA-approved medications extend the lifespan in C. elegans, raising the possibility that they can also extend the lifespan in humans. The renin-angiotensin system (RAS) in mammals is an endocrine system that regulates blood pressure and a paracrine system that acts in a wide range of tissues to control physiological processes; it is a popular target for drugs that reduce blood pressure, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs). Emerging evidence indicates that this system influences aging. In C. elegans, decreasing the activity of the ACE homolog acn-1 or treatment with the ACE-inhibitor Captopril significantly extends the lifespan. In Drosophila, treatment with ACE inhibitors extends the lifespan. In rodents, manipulating the RAS with genetic or pharmacological interventions can extend the lifespan. In humans, polymorphisms in the ACE gene are associated with extreme longevity. These results suggest the RAS plays a conserved role in controlling longevity. Here, we review studies of the RAS and aging, emphasizing the potential of C. elegans as a model for understanding the mechanism of lifespan control.

Reproductive Aging in Caenorhabditis elegans: From Molecules to Ecology.

Aging animals display a broad range of progressive degenerative changes, and one of the most fascinating is the decline of female reproductive function. In the model organism Caenorhabditis elegans, hermaphrodites reach a peak of progeny production on day 2 of adulthood and then display a rapid decline; progeny production typically ends by day 8 of adulthood. Since animals typically survive until day 15 of adulthood, there is a substantial post reproductive lifespan. Here we review the molecular and cellular changes that occur during reproductive aging, including reductions in stem cell number and activity, slowing meiotic progression, diminished Notch signaling, and deterioration of germ line and oocyte morphology. Several interventions have been identified that delay reproductive aging, including mutations, drugs and environmental factors such as temperature. The detailed description of reproductive aging coupled with interventions that delay this process have made C. elegans a leading model system to understand the mechanisms that drive reproductive aging. While reproductive aging has dramatic consequences for individual fertility, it also has consequences for the ecology of the population. Population dynamics are driven by birth and death, and reproductive aging is one important factor that influences birth rate. A variety of theories have been advanced to explain why reproductive aging occurs and how it has been sculpted during evolution. Here we summarize these theories and discuss the utility of C. elegans for testing mechanistic and evolutionary models of reproductive aging.

Impact of rapeseed pomace extract on markers of oxidative stress and DNA damage in human SH-SY5Y cells.

With increased longevity and subsequent rise in people with age-related neurodegenerative diseases, protection of neurons from oxidative stress damage has become an important field of study. For the first time, we highlight the neuroprotective properties of rapeseed pomace (RSP) extract in SH-SY5Y human neuroblastoma cells. We used resazurin to determine cell metabolism, 2,7'-dichlorofluorescin diacetate (H2 DCFDA) to assess the potential of RSP extracts to shield cells from reactive oxygen species (ROS) induced by H2 O2 using flow cytometry, HPLC to analyze for malondialdehyde (MDA) as a lipid peroxidation marker and the COMET assay to assess DNA strand breakage. Protein stress arrays were used to investigate the cellular pathways affected by RSP extract. No effect on cell metabolism in SH-SY5Y cells was observed after RSP extract treatment (up to 1.5 mg/ml). Pretreatment (24 hr) with RSP extract (1 mg/ml), before H2 O2 -induced stress, alleviated ROS production and DNA strand breakage by 68%, and 38%, respectively. At protein level, the RSP extract increased the levels of FABP-1, HIF-1α, SOD2, and Cytochrome c proteins. Under H2 O2 -induced stress, however, it helped to downregulate p38α levels, a protein kinase which is receptive to stress impulse (mitogen-activated). RSP extract shows very promising cell protective properties in relation to oxidative stress. PRACTICAL APPLICATIONS: Oxidative stress has been associated with numerous diseases for example cancer, diabetes, and many neurological disorders including Parkinson's and Alzheimer's diseases. Hence, there is acceptance among the scientific community of antioxidant therapy and the quest for effective, low cost and readily available sources of natural antioxidants is paramount. Rapeseed plantations are abundant around the world due to the use of rapeseed oil in cooking and as a biofuel. The resulting rapeseed pomace (by-product), specifically its extract, contains high levels of phytochemicals that protect cells against oxidative stress. Therefore, RSP extract can potentially be used/developed as functional food and nutraceuticals in the prevention of many complex neurodegenerative diseases.

A clickable probe for versatile characterization of S-nitrosothiols.

S-nitrosation of cysteine thiols (SNOs), commonly referred to as S-nitrosylation, is a cysteine oxoform that plays an important role in cellular signaling and impacts protein function and stability. Direct labeling of SNOs in cells with the flexibility to perform a wide range of cellular and biochemical assays remains a bottleneck as all SNO-targeted probes to date employ a single analytical modality such as biotin or a specific fluorophore. We therefore developed a clickable, alkyne-containing SNO probe 'PBZyn' based on the o-phosphino-benzoyl group warhead that enables multi-modal analysis via click conjugation. We demonstrate the utility of PBZyn to assay SNOs using in situ cellular imaging, protein blotting and affinity purification, as well as mass spectrometry. The flexible PBZyn probe will greatly facilitate investigation into the regulation of SNOs.

Determination of sinapine in rapeseed pomace extract: Its antioxidant and acetylcholinesterase inhibition properties.

Sinapine is the main secondary metabolite present in rapeseed pomace (RSP) with its concentration being dependent on rapeseed processing, growing conditions, extraction parameters and the country of origin. Here we report, the concentration of sinapine from an extract of defatted RSP harvested in the North East of Scotland. Using liquid chromatography tandem mass spectrometry, the most abundant phenolic compound in the RSP extract was, as expected, sinapine (109.1 mg/g RSP extract). Additionally, sinapic, caffeic, ferulic and syringic acids were identified (0.159-3.91 mg/g RSP extract). Sinapine together with the phenolics at the concentration present in the RSP extract, exhibited ≥50% activity relative to the extract in antioxidant assays. Furthermore, sinapine provided plasmid DNA (pBR322) protection, from 2,2'-azobis(2-amidinopropane) dihydrochloride and inhibited acetylcholinesterase activity by 85%. Molecular docking was utilised to explain the inhibitory activity. RSP can be an excellent source of bioactive compounds for pharmaceuticals, food additive and nutraceutical applications.

GST-4-Dependent Suppression of Neurodegeneration in C. elegans Models of Parkinson's and Machado-Joseph Disease by Rapeseed Pomace Extract Supplementation.

Genetic mutations and aging-associated oxidative damage underlie the onset and progression of neurodegenerative diseases, like Parkinson's disease (PD) and Machado-Joseph disease (MJD). Natural products derived from plants have been regarded as important sources of novel bioactive compounds to counteract neurodegeneration. Here, we tested the neuroprotective effect of an ethanolic extract of rapeseed pomace (RSP), a rapeseed (canola) oil production by-product, in C. elegans models of MJD and PD. The extract, containing sinapine and other phenolics, restored motor function of mutant ataxin-3 (ATXN3) animals (MJD) and prevented degeneration of dopaminergic neurons in one toxin-induced and two genetic models of PD. Whole-organism sensors of antioxidant and xenobiotic response activation revealed the induction of phase II detoxification enzymes, including glutathione S- transferase (GST-4) upon RSP extract supplementation. Furthermore in vivo pharmacogenetic studies confirmed gst-4 is required for the therapeutic effect of RSP extract in the two disease models. The results suggest that GST-4-mediated antioxidant pathways may constitute promising therapeutic co-targets for neurodegenerative diseases and confirm the utility of searching for bioactive compounds in novel sources, including food and agricultural waste/by-products, such as RSP.

Revalorisation of rapeseed pomace extracts: An in vitro study into its anti-oxidant and DNA protective properties.

Rapeseed pomace (RSP) is a waste product obtained after edible oil production from Brassica napus. Analysis of ubiquitous secondary metabolites in RSP samples (two breeds, harvested in 2012/2014 respectively from North East of Scotland) and their ethanol/water (95:5) Soxhlet extracts were carried out. Soxhlet extraction of the RSP (petroleum ether followed by 95% ethanol) gave a solid extract. LC-MS/MS data of the extracts revealed several secondary metabolites, with Sinapic acid being the most abundant. Strong antioxidant activities of the Soxhlet extracts were confirmed from the results obtained in the FRAP, DPPH and ORAC assays. Furthermore, for the very first time, RSP extracts (13.9µg/ml) provided complete DNA protection, from oxidative stress induced by AAPH (3.5mM). Therefore the strong antioxidant and DNA protecting properties demonstrated by the RSP extracts in this study warrants further investigation for their revalorisation and potential use as reliable source of antioxidants in different food applications.