Flavin-containing monooxygenases (FMOs) have historically been studied as xenobiotic metabolizing enzymes, but emerging data are consistent with a role for FMOs affecting longevity and metabolism through action on one or more endogenous substrates. Caenorhabditis elegans flavin-containing monooxygenase-2 (fmo-2) is necessary for the effects of multiple major longevity interventions including dietary restriction, and its overexpression is sufficient to extend lifespan. Despite this longevity-promoting role, the mechanisms by which FMO-2 extends lifespan remain undefined. We sought to test the hypothesis that fmo-2 interacts with the sulfur amino acid pathway to extend lifespan by screening RNAi clones of sulfur amino acid pathway genes for lifespan effects on wild type, FMO-2 overexpressor, and fmo-2(ok2147) loss-of-function mutant worms. We found that the increase in longevity induced by the overexpression of FMO-2 requires glutathione reductase, and that fmo-2(ok2147) worms are sensitive to the healthspan-shortening effects of glutathione synthesis RNAi. Additionally, HPLC analysis revealed that fmo-2(ok2147) worms synthesize significantly less glutathione. Our results are consistent with a model in which FMO-2 oxidizes glutathione to stimulate normal glutathione synthesis. This research serves to extend our understanding of the function of FMOs and provides insight into a mechanism by which cells maintain the reducing environment necessary for many metabolic pathways. 

Aging is the single largest risk factor for many diseases, including Alzheimer’s disease (AD). Therefore, many of the molecular mechanisms that cause aging may also contribute to the onset and progression of aging-related diseases. Our approach to tackling the progression of AD takes a biology of aging standpoint, where screening compounds (FDA approved or naturopathic) that impact lifespan may help identify therapies for AD. This is a novel approach with the potential to accelerate clinical translation. This study uses a human Amyloid-beta (Aß) protein-expressing C. elegans strain that becomes progressively paralyzed with age. Utilizing a novel robotic imaging system (the WormBot), we show the impact these compounds have on AD progression through quantification of a delay in paralysis, then behavioral data and health metrics are collected by tracking worm motility over their entire lifespan. Three compounds have been identified to delay paralysis: Thioflavin T, alpha-lipoic acid and resveratrol, all of which we have shown to increase lifespan. We expect to see Thioflavin-T to have a strong influence on paralysis due to its disruption in Aß aggregation. Resveratrol and alpha-lipoic acid's inflence is expected to be associated with its impact on increasing lifespan. Both behavior and binary paralysis results under these three compounds exposure provide holistic insight into mechanisms of Aß toxicity and could lead to promising treatments that have the potential to increase the quality of life for Alzheimer’s disease patients.

Numerous interventions and genetic modifications have been shown to extend lifespan across a diversity of species. However, these studies often assume that extended lifespan is synonymous with extended healthspan. Recent research in the nematode worm, Caenorhabditis elegans, has questioned this assumption, and suggests that increasing lifespan can prolong the frailty associated with old age. This is particularly important for humans, as increasing lifespan without a corresponding increase in healthspan could spell disaster. The majority of healthcare costs are associated with aging-related pathologies, and prolonging life without prolonging health could radically inflate these costs. To parse out the genetic relationship between healthspan and lifespan, we have turned to Drosophila melanogaster, a well characterized model organism for studies on the genetics of aging. We have collected lifespan data as well as multiple measures of healthspan, such as negative geotaxis (climbing), intestinal permeability, Cold stress resistance, and metabolomics data across 16 inbred genotypes. We found a strong positive correlation between lifespan and climbing, and no correlation between cold stress resistance and lifespan. This confirms the importance of lifespan as a primary parameter in aging studies, but suggests additional measures of health are needed to accurately assess health. 

Astrocytes are characteristic star-shaped glial cells, and they are the largest and most numerous nonneuronal cells in the brain. They are involved in cell signaling, providing nutrients to neurons, removing toxins, repair and anti-inflammation response in the brain. However, relatively little attention has been paid to this cell type compared to neurons in neurodegenerative conditions, such as age-related cognitive impairment and Alzheimer’s disease. The basic question is: what functional changes occur in astrocytes with increasing age that could relate to vulnerability to neurodegeneration. C57BL/6 mice in age cohorts of 8 months, 16 months, 24 months, and 32 months were tested in a radial water tread maze, a well-standardized measure of contextual learning and memory in the mice. Brain tissues were then collected and parasagitally sectioned and stained with GFAP (Glial Fibrillary Acidic Protein), an immuno-reactive marker for astrocytes. In general, 8-month old mice showed very little cognitive impariment while several 16-month old mice showed mild cognitive impairment, but 24 and 32-month old mice showed moderate to severe cognitive impairment. Concurrent with this increase in cognitive impairment was an increase in ImageJ pixel intensity of GFAP immunohistochemistry staining of astrocytes with increasing age. This preliminary observation suggests that astrocytes are predominantly present with increasing age and decreasing cognitive ability and provides the rationale for further investigations into what role these nonneuronal cells are playing in brain health.

Sleep deprivation (SD) is a major health concern in developed countries, especially in the elderly, and is associated with physiological disturbances including cognitive impairment, increased risk of dementia, and leads to the acceleration of neurodegenerative disorders such as Alzheimer’s disease. A logical question is whether cognitive impairment associated with SD can be prevented. To address this question, 22-month-old C57BL/6 mice were sleep deprived during the middle of their sleep cycle for four hours each day for two days. Three days before the SD procedure, treatment was started with the anti-aging peptide glycyl-L-histidyl-L-lysine (GHK) 15 mg/kg per day for five days through the two-day SD procedure. GHK has wound healing and anti-inflammatory properties and readily passes through the blood-brain barrier. Immediately following the last day of SD and GHK treatment, mice were tested for learning impairment using a spatial learning activity which requires them to find the escape hole. Tissues were then collected for neuropathology assessment. Sleep deprived mice treated with GHK consistently found the escape hole more quickly than sleep deprived mice treated with saline suggesting that GHK can prevent the learning impairment associated with short term sleep deprivation. This preliminary observation provides the rationale to investigate the neuro-molecular and neuropathological pathways targeted by GHK including inflammation, oxidative stress and vascular dysfunction.

Senescence is a gradual deterioration of functional characteristics. At the cellular level, it is defined as a loss of the ability to divide and carryout normal cellular activities that contribute to the health and well being of a cell. In fact, senescent cells secrete inflammatory cytokines that contribute to aging. Therefore, preventing senescence could have an impact on preventing aging. To address this issue, 21-month-old C57BL/6 mice were fed standard rodent chow containing three well-validated anti-aging drugs, rapamycin, acarbose, and phenylbutyrate for 3 months. Each drug targets different but overlapping aging processes. At the end of 3 months mice were tested for cognition and physiological performance and tissues collected for assessing senescence by reverse transcriptase polymerase chain reaction using well-accepted senescence markers including p16. Preliminary observations suggest that the drug cocktail in just 3 months delayed aging by improving cognitive and physiological performance tasks. Preliminary data from liver samples tested by reverse transcriptase polymerase chain reaction showed that mice treated with the drug cocktail had less P16 expression than mice fed a diet without the drug cocktail. More work is needed to sort out how each drug is contributing to this anti-senescence effect, but the preliminary observation suggests preventing or delaying senescence may be an informative target for investigations into delaying or preventing aging.

In humans, aging is a major risk factor for high-mortality diseases such as cancer, heart disease, and Alzheimer’s, all of which do not currently have cures. One hypothesis is that by treating the aging process underlying these maladies, the progression of the diseases will also be alleviated. It has been found that many of the aging processes in the single celled eukaryote, Saccharomyces cerevisiae are also conserved in multi-cellular eukaryotes such as humans. One characteristic of aging yeast is the accumulation of extra-chromosomal rDNA circles (ERCs). rDNA is a repetitive region of the genome that encodes for ribosomes: cellular machinery that produces proteins. ERCs are small pieces of rDNA that become excised from the chromosome during homologous recombination. It is commonly thought that ERCs are a consequence of aging and that they build up over time and lead to cell death. My project investigates if ERCs have an evolutionary function that has been selected for. It is known that older yeast cells survive better on non- optimal carbon sources, such as galactose, compared to young yeast cells. I hypothesize that ERCs aid aging yeast cells in surviving on non-optimal carbon sources as an evolutionary adaptation. Sir2 suppresses the creation of ERCs and I have controled the amount of ERCs that accumulate in the cells by using a strain of yeast with a Sir2 deletion alongside a strain with Sir2 overexpression. I grew these strains on either dextrose or galactose to see if varying Sir2 activity affects old cells ability to grow on non-optimal carbon sources. Then I passaged these strains over many generations on glucose or galactose to see if ERC accumulation is favored in non-optimal carbon environments. We will also be quantifying ERC copy number through gel electrophoresis and quantitative Southern blotting.