Marshall Miller

• Doctor of Philosophy
• PostDoc Position at Duke University Medical Center

Background/Objectives: Generous consumption of phytonutrient-rich foods, including blueberries, provides benefits to multiple physiologic and metabolic systems. This study explored the potential that regular, generous blueberry intake could favorably modulate fecal microbiome composition in sedentary older (>60 years) men and women with overweight...

The world is now distressed with the coronavirus disease (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although vaccination is not done in full fledge and a particular drug is not available to treat COVID-19, modern technologies help humanity fight against it. Data science is a part of modern technological a...

On exploratory class missions, such as a mission to Mars, astronauts will be exposed to doses of particles of high energy and charge and protons up to 30 - 40 cGy. These exposures will most likely occur at random intervals across the estimated 3-yr duration of the mission. As such, the possibility of an interaction between particles must be taken i...

Profound restrictions were placed on previously free-living older adults due to mandatory stay-at-home orders for Covid-19. Recognizing the potential for worsening health and heightened risk of Covid-19 complications with older age and obesity, we conducted a survey to assess the impact of stay-at-home requirements on diet, health/social behaviors,...

Objectives Research suggests that supplementation with berries may improve cognition during aging. In two recently published 90-day trials, healthy older adults (ages 60–75; BMI 18.5–29.9) who consumed 24 g/d freeze-dried blueberry or strawberry showed improved cognitive function, relative to placebo controls. However, the mechanism of action under...

In contrast to recommendations for young and middle-aged adults, intentional weight loss among older adults remains controversial and is inconsistently advised. Recent research suggests that a higher protein diet can mitigate loss of lean mass during periods of intentional weight loss among older adults with obesity; however, the effects of intenti...

Functional changes in the brain during aging can alter learning and memory, gait, and balance - in some cases leading to early cognitive decline, disability, or injurious falls among older adults. Dietary interventions with strawberry (SB) have been associated with improvements in neuronal, psychomotor, and cognitive function in rodent models of ag...

Blueberries (BB) contain an array of bioactive phenolic compounds that may play a protective role against various age-related diseases. Here we explored the metabolic fate of BB phenolics and their relationship to cognitive function after chronic (90 days) supplementation of freeze-dried BB (24 g d⁻¹, equivalent to 1 cup of fresh BB) or control in...

Obesity hastens functional decline and intensifies chronic health conditions among older adults. Late-life obesity is of particular concern for older African Americans, who are at increased risk for obesity and type 2 diabetes and for whom weight loss interventions can be less effective. However, obesity interventions have been under-studied in thi...

Blacks have higher rates of obesity and are twice as likely to develop diabetes as non-Hispanic whites. Obesity reduction can improve metabolic health, but physical function and glucose handling may be threatened by concomitant loss of muscle mass. These preliminary findings from a 4-mo. randomized controlled trial assess the racial differences in...

The extended social isolation necessitated by the COVID-19 pandemic will likely have a prolonged negative impact on the health of community-dwelling older adults. We studied the potential to counteract these negative effects, examining the before and after measurements of participants in two obesity intervention studies that were converted from in-...

Objectives Weight loss interventions for older adults often reduce bone mineral density (BMD), increasing risk of subsequent detrimental outcomes. This study explored the long-term impact of a higher protein diet plus exercise versus a diet plus exercise control treatment on body weight, bone mineral density at 3 sites, and fracture risk. Methods...

Objectives Obesity rates in older adults are rapidly climbing, especially in older African Americans, for whom it hastens functional decline and intensifies chronic health conditions like Type 2 diabetes more so than in their white counterparts. Emerging evidence suggest that increased protein intake can enhance the benefits of intentional weight l...

Berry fruits contain a variety of bioactive polyphenolic compounds that exhibit potent antioxidant and anti-inflammatory activities. We have shown that consumption of freeze-dried whole berry powder, equivalent to 1 cup/day of blueberry (BB) or 2 cups/day of strawberry (SB), can differentially improve some aspects of cognition in healthy, older adu...

Nutritional status is a strong determinant of both body composition and physical function (PF), parameters that are closely interrelated but rarely evaluated in the clinical setting due to cost, access, and lack of agreement on best approaches in older adults. Recent evidence that changes in muscle mass do not closely correspond to changes in muscl...

Racial/ethnic differences in obesity prevalence and in responses to weight-loss treatment between Black and White women are well documented. Whether these differences influence responses to weight-loss treatment among older women is unknown. Therefore, we evaluated racial/ethnic differences among participants in a 6-month weight-loss study with tra...

Exposure to the types of radiation encountered outside the magnetic field of the earth can disrupt cognitive performance. Exploratory class missions to other planets will include both male and female astronauts. Because estrogen can function as a neuroprotectant, it is possible that female astronauts may be less affected by exposure to space radiat...

Objectives: Obesity affects a growing number of older adults, contributing to poor physical and mental health outcomes; meanwhile, treatments to reduce obesity in older adults are complicated by a relatively limited treatment window and potential loss of lean mass. Furthermore, obesity's prevalence is unevenly distributed and highest among black a...

Objectives: With soaring rates of geriatric obesity, a major shift in understanding of the relationship between body mass and bone health is unfolding. The premise that obesity is protective of bone runs counter to evidence that obesity factors like increased inflammation and reduced physical activity may increase fracture risk. Methods: Obese (...

Daily supplementation of blueberries (BBs) reverses age-related deficits in behavior in aged rats. However, it is unknown whether BB is more beneficial to one subset of the population dependent on baseline cognitive performance and inflammatory status. To examine the effect of individual differences on the efficacy of BB, aged rats (17 mo old) were...

An obese body weight, once presumed protective against bone fractures in older adults, has recently been linked with reduced bone quality. Thus, we assessed indicators of fracture risk in obese (mean BMI 35 ± 5 kg/m2) female (n=58) and male (n=16) older adults (age =70 ± 6 yrs; 49% black) with functional limitations (mean Short Physical Performance...

Obesity affects a large proportion of older adults, contributing to poor physical and mental health outcomes. Yet, weight loss (WL) interventions have been under-studied in this population due to concerns about exacerbating age-related reductions in muscle mass, bone density, and physical function. Thus, the potential influence of WL interventions...

PurposeAs populations shift to include a larger proportion of older adults, the necessity of research targeting older populations is becoming increasingly apparent. Dietary interventions with blueberry have been associated with positive outcomes in cell and rodent models of aging. We hypothesized that dietary blueberry would improve mobility and co...

Strawberries contain a wide array of nutrients and phytochemicals including polyphenols such as anthocyanins, procyanidins and ellagitannins. These polyphenols are absorbed and metabolized to various phenolic metabolites/conjugates in the body, which may play a role in disease risk reduction. In the present study, we investigated the metabolic fate...

Exposure to particles of high energy and charge (HZE particles) can produce decrements in cognitive performance. A series of experiments exposing rats to different HZE particles was run to evaluate whether the performance decrement was dependent on the age of the subject at the time of irradiation. Fischer 344 rats that were 2-, 11- and 15/16-month...

Among older adults, falls are a leading cause of distress, pain, injury, loss of confidence, and ultimately, loss of independence and death. Previous studies in our laboratory have demonstrated that berry supplementation improves the age-related declines in balance, muscle strength, and coordination that often lead to falls, even when initiated lat...

Plant derived anthocyanin rich foods play a protective role against chronic diseases such as diabetes, obesity, cardiovascular, cancer and neurodegenerative diseases. Anthocyanins are absorbed in their intact form and can be metabolized to a wide array of phenolic metabolites/conjugates. Blueberries are considered to be one of the richest source of...

Frailty is a clinical syndrome that is increasingly prevalent during aging. Frailty involves the confluence of reduced strength, speed, physical activity, and endurance and is associated with adverse health outcomes. The present study adapts existing clinical and preclinical indices of frailty to the Fischer (F344) rat. Male F344 rats (n = 133; 17...

The protective effects of anthocyanin-rich blueberries (BB) on brain health are well documented and are particularly important under conditions of high oxidative stress, which can lead to “accelerated aging.” One such scenario is exposure to space radiation, consisting of high-energy and -charge particles (HZE), which are known to cause cognitive d...

Population aging is leading to an increase in the incidence of age-related cognitive dysfunction and, with it, the health care burden of caring for older adults. Epidemiological studies have shown that consumption of fruits, nuts, and vegetables is positively associated with cognitive ability; however, these foods, which contain a variety of neurop...

Advanced glycation end products (AGEs) are naturally occurring macromolecules that are formed in vivo by the non-enzymatic modification of proteins, lipids, or nucleic acids by sugar, even in the absence of hyperglycemia. In the diet, AGEs are found in animal products, and additional AGEs are produced when those foods are cooked at high temperature...

High consumption of fruits and vegetables has been associated with reduced risk of debilitating diseases and improved cognition in aged populations. These beneficial effects have been attributed to the phytochemicals found in fruits and vegetables, which have previously been shown to be anti-inflammatory and modulate autophagy. Tart cherries contai...

Older adults experience a variety of functional changes that decrease their quality of life with age‐related cognitive decline and reduced mobility being of particular concern. Pre‐clinical research indicates that berry fruit offer a promising dietary approach to preserving nervous system function, in part due to the antioxidant and anti‐inflammato...

Objectives: The present study was carried out to determine if lyophilized açaí fruit pulp (genus, Euterpe), rich in polyphenols and other bioactive antioxidant and anti-inflammatory phytochemicals, is efficacious in reversing age-related cognitive deficits in aged rats. Methods: The diets of 19-month-old Fischer 344 rats were supplemented for 8...

Decline in brain function during normal aging is partly due to the long-term effects of oxidative stress and inflammation. Several fruits and vegetables have been shown to possess antioxidant and anti-inflammatory properties. The present study investigated the effects of dietary mushroom intervention on mobility and memory in aged Fischer 344 rats....

Chronic inflammation is thought to play a role in age‐related cognitive decline. Previous studies from our laboratory have shown that dietary intervention with darkly pigmented berry fruit can reduce systemic and central biomarkers of inflammation while reversing behavioral impairments in aged rats. In the present study, older men and women (60‐75...

Because of the combination of population growth and population aging, increases in the incidence of chronic neurodegenerative disorders have become a societal concern, both in terms of decreased quality of life and increased financial burden. Clinical manifestation of many of these disorders takes years, with the initiation of mild cognitive sympto...

Açai is a black‐purple fruit (genus Euterpe) cultivated in the Amazon delta and in Brazil (Euterpe oleracea Mart. ‐EO), as well as Bolivia (Euterpe precatoria Mart. ‐ EP), and it is known to be rich in polyphenolics that may affect cell‐to‐cell signaling, receptor sensitivity, inflammatory enzyme activity, oxidant/antioxidant balance, and gene regu...

Aged rats show impaired performance on motor and cognitive tasks. Similar changes in behavior occur in humans with age, and the development of methods to retard or reverse these age‐related neuronal and behavioral deficits could increase healthy aging and decrease health care costs. In the present study, men and women, 21–75 years of age, were recr...

The complex mixture of phytochemicals in fruits and vegetables provides protective health benefits, mainly through additive and/or synergistic effects. The presence of several bioactive compounds, such as polyphenols and caffeine, implicates coffee as a potential nutritional therapeutic in aging. Moderate (three to five cups a day) coffee consumpti...

Introduction Alzheimer's disease Coffee Caffeine Phenolics Other coffee constituents Conclusions References

Increased lifespans have led to population aging and brought attention to healthcare concerns associated with old age. A growing body of preclinical and clinical research has identified neurological benefits associated with the consumption of berry fruits. In addition to their now well-known antioxidant effects, dietary supplementation with berry f...

Glucocorticoids (GC)--corticosterone (CORT) in rodents and cortisol in primates--are stress-induced hormones secreted by adrenal glands that interact with the hypothalamic pituitary axis. High levels of cortisol in humans are observed in neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD), as well as in diabe...

We have previously reported that a modified Stone T-maze (STM), using escape from water as motivation, was effective in evaluating learning and memory ability in young C57/BL6 mice. Here we report on the effectiveness and sensitivity of the STM in the assessment of age-related learning and memory deficits in mice using either escape from foot shock...

IntroductionBlack, oolong and green tea (C. sinensis)Other teas and tisanesSummary and conclusionsReferences

Oxidative DNA damage plays a role in disease development and the aging process. A prominent participant in orchestrating the repair of oxidative DNA damage, particularly single-strand breaks, is the scaffold protein XRCC1. A series of chronological and biological aging parameters in XRCC1 heterozygous (HZ) mice were examined. HZ and wild-type (WT)...

Conservation of normal cognitive functions relies on the proper performance of the nervous system at the cellular and molecular level. The mammalian nicotinamide-adenine dinucleotide-dependent deacetylase SIRT1 impacts different processes potentially involved in the maintenance of brain integrity, such as chromatin remodeling, DNA repair, cell surv...

While studies of long-term calorie restriction (CR) have pointed to a plethora of health benefits in numerous species including humans, the effects on the brain and brain function are less well known and understood. In this chapter the effect of long-term CR on learning and memory in aging populations of laboratory rats and mice is evaluated. Inclu...

Previous research has shown that radiation exposure, particularly to particles of high energy and charge (HZE particles) which will be encountered on long-term space missions, can adversely affect the ability of rats to perform a variety of behavioral tasks. This outcome has implications for an astronaut's ability to successfully complete requireme...

Diabetes and normal aging are both characterized by increases in levels of glucocorticoids. Because long-term exposure to elevated glucocorticoids can be detrimental to hippocampal function, we evaluated the performance of young diabetic rats in the 14-unit T-maze, a task that is sensitive to hippocampal deficits. To assess the contribution of diab...

The 14-unit T-maze has proven to be a valuable tool for investigating age-associated memory impairment (AAMI). While another task widely used to evaluate AAMI, the water maze, is primarily used to evaluate allocentric hippocampal-dependent spatial memory, the 14-unit T-maze can assess egocentric procedural memory. Although several brain structures,...