Publications by authors named "Mariah Calubag"

Deciphering the complex interplay between neuronal activity and mitochondrial function is pivotal in understanding brain aging, a multifaceted process marked by declines in synaptic function and mitochondrial performance. Here, we identified an age-dependent coupling between neuronal and synaptic excitation and mitochondrial DNA transcription (E-TC), which operates differently compared to classic excitation-transcription coupling in the nucleus (E-TC). We demonstrated that E-TC repurposes molecules traditionally associated with E-TC to regulate mitochondrial DNA expression in areas closely linked to synaptic activation.

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Restricting the intake of protein or the branched-chain amino acid isoleucine promotes healthspan and extends lifespan in young or adult mice. However, their effects when initiated in aged animals are unknown. Here we investigate the consequences of consuming a diet with 67% reduction of all amino acids (low AA) or of isoleucine alone (low Ile), in male and female C57BL/6J.

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Caloric restriction (CR) is a widely recognized geroprotective intervention that slows or prevents Alzheimer's disease (AD) in animal models. CR is typically implemented via feeding mice a single meal per day; as CR mice rapidly consume their food, they are subject to a prolonged fast between meals. While CR has been shown to improve metabolic and cognitive functions and suppress pathological markers in AD mouse models, the specific contributions of fasting versus calorie reduction remains unclear.

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Age is the greatest risk factor for Alzheimer's disease (AD) as well as for other disorders that increase the risk of AD such as diabetes and obesity. There is growing interest in determining if interventions that promote metabolic health can prevent or delay AD. Acarbose is an anti-diabetic drug that not only improves glucose homeostasis, but also extends the lifespan of wild-type mice.

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Cellular senescence, a process in which a cell exits the cell cycle in response to stressors, is one of the hallmarks of aging. Senescence and the senescence-associated secretory phenotype (SASP)-a heterogeneous set of secreted factors that disrupt tissue homeostasis and promote the accumulation of senescent cells-reprogram metabolism and can lead to metabolic dysfunction. Dietary interventions have long been studied as methods to combat age-associated metabolic dysfunction, promote health, and increase lifespan.

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Age is the greatest risk factor for Alzheimer's disease (AD) as well as for other disorders that increase the risk of AD such as diabetes and obesity. There is growing interest in determining if interventions that promote metabolic health can prevent or delay AD. Acarbose is an anti-diabetic drug that not only improves glucose homeostasis, but also extends the lifespan of wild-type mice.

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Dietary protein is a critical regulator of metabolic health and aging. Low protein diets are associated with healthy aging in humans, and dietary protein restriction extends the lifespan and healthspan of mice. In this study, we examined the effect of protein restriction (PR) on metabolic health and the development and progression of Alzheimer's disease (AD) in the 3xTg mouse model of AD.

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Article Synopsis
  • - Low-protein diets enhance health and lifespan across different species, with specific emphasis on the benefits of restricting branched-chain amino acids (BCAAs) in mice.
  • - A study showed that a restriction of isoleucine (IleR) led to improved metabolic health, promoting leanness and better blood sugar control in both young and old genetically diverse UM-HET3 mice.
  • - IleR not only reduced frailty but also extended the lifespan of mice, especially in males, indicating its potential as a geroprotective strategy either through dietary changes or drugs that mimic its effects.
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Dietary protein is a critical regulator of metabolic health and aging. Low protein diets are associated with healthy aging in humans, and many independent groups of researchers have shown that dietary protein restriction (PR) extends the lifespan and healthspan of mice. Here, we examined the effect of PR on metabolic health and the development and progression of Alzheimer's disease (AD) in the 3xTg mouse model of AD.

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The activity-dependent plasticity of synapses is believed to be the cellular basis of learning. These synaptic changes are mediated through the coordination of local biochemical reactions in synapses and changes in gene transcription in the nucleus to modulate neuronal circuits and behavior. The protein kinase C (PKC) family of isozymes has long been established as critical for synaptic plasticity.

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Article Synopsis
  • Dietary protein plays a key role in healthy aging, with low-protein diets extending lifespan and improving healthspan in mice.
  • A significant reduction in amino acids, either overall or specifically isoleucine, led to decreased body fat and better glucose tolerance without cutting calorie intake.
  • Both dietary regimens also showed improvements in frailty and molecular markers of aging, suggesting potential benefits for healthy aging in older individuals.
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The hippocampus, a medial temporal lobe brain region, is critical for the consolidation of information from short-term memory into long-term episodic memory and for spatial memory that enables navigation. Hippocampal damage in humans has been linked to amnesia and memory loss, characteristic of Alzheimer's disease and other dementias. Numerous studies indicate that the rodent hippocampus contributes significantly to long-term memory for spatial and nonspatial information.

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Calorie restriction (CR) promotes healthspan and extends the lifespan of diverse organisms, including mice, and there is intense interest in understanding the molecular mechanisms by which CR functions. Some studies have demonstrated that CR induces fibroblast growth factor 21 (FGF21), a hormone that regulates energy balance and that when overexpressed, promotes metabolic health and longevity in mice, but the role of FGF21 in the response to CR has not been fully investigated. We directly examined the role of FGF21 in the physiological and metabolic response to a CR diet by feeding and wild-type control mice either (AL) diet or a 30% CR diet for 15 weeks.

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Senescent cells accumulate with age in vertebrates and promote aging largely through their senescence-associated secretory phenotype (SASP). Many types of stress induce senescence, including genotoxic stress. ERCC1-XPF is a DNA repair endonuclease required for multiple DNA repair mechanisms that protect the nuclear genome.

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