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Bottiglieri, T.

Publications and source records attributed to Bottiglieri, T..

4 recordsLinked to original sources

Maternal dietary deficiencies in folates or choline during pregnancy and lactation worsen stroke outcome in 3-month-old male and female mouse offspring

Maternal one-carbon (1C) metabolism plays an important role in early life programming. There is a well-established connection between the fetal environment and the health status of the offspring. However, there is a knowledge gap on how maternal nutrition impacts stroke outcome in offspring. The aim of our study was to investigate the role of maternal dietary deficiencies in folic acid or choline on stroke outcome in 3-month-old offspring. Adult female mice were fed a folic acid deficient diet (FADD), choline deficient diet (ChDD), or control diet (CD) prior to pregnancy. They were continued on diets during pregnancy and lactation. Male and female offspring were weaned onto a CD and at 2 months of age were subject to ischemic stroke within the sensorimotor cortex via photothrombosis damage. At 3-months-of-age, motor function was measured in offspring and tissue was collected for analysis. Mothers maintained on either a FADD or ChDD had reduced levels of S-adenosylmethionine in liver and S-adenosylhomocysteine in plasma. After ischemic stroke, motor function was impaired in 3-month-old offspring from deficient mothers compared to CD animals. In brain tissue, there was no difference in ischemic damage volume. When protein levels were assessed in brain tissue, there were lower levels of neurodegeneration in males compared to females and betaine levels were reduced in offspring from ChDD mothers. Our results demonstrate that a deficient maternal diet during critical timepoints in neurodevelopment results in worse stroke outcomes. This study emphasizes the importance of maternal diet and the impact it can have on offspring health.

neuroscience↗

Reduced stroke outcome in old-aged female mice maintained on a dietary vitamin B12 deficiency

The global population is aging and the prevalence of age-related diseases, such as stroke, is predicted to increase. A vitamin B12 deficiency (vit. B12 def.) is common in the elderly, because of changes in metabolism. Clinical studies have reported that a vit. B12 def results in worse outcome after stroke, the mechanisms through which a vit. B12 def. changes the brain requires further investigation. This study investigated the role of vit. B12 def. on stroke outcome and mechanisms using aged female mice. Eighteen month old females were put on a control or vit. B12 def. diet for four weeks, after which an ischemic stroke was induced in the sensorimotor cortex. After damage, motor function was measured and animals were euthanized and tissues were collected for analysis. Vit. B12 def. animals had increased levels of total homocysteine in plasma and liver, choline levels were also increased in the liver. Vit. B12 def. animals had larger damage volume in brain tissue and more apoptosis. In the cecum, changes in creatinine and methylmalonic acid were observed in vit. B12 def. animals, pathway analysis showed dysfunction in B12 transport. Analysis of mitochondrial metabolomics in brain tissue showed reduced levels of metabolites involved in the TCA cycle in vit. B12 def animals. Meanwhile, pathway analysis showed significant, widespread dysfunction in phenylalanine, tyrosine, and tryptophan biosynthesis. Motor function after stroke was impaired in vit. B12 def. animals. A dietary vitamin B12 deficiency impairs motor function through increased apoptosis and changes in mitochondrial metabolism in brain tissue.

physiology↗

The 677C>T variant in methylenetetrahydrofolate reductase causes morphological and functional cerebrovascular deficits in mice

Vascular contributions to cognitive impairment and dementia (VCID) particularly Alzheimers disease and related dementias (ADRDs) are increasing; however, mechanisms driving cerebrovascular decline are poorly understood. Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in the folate and methionine cycles. Variants in MTHFR, notably 677C>T, are associated with dementias, but no mouse model existed to identify mechanisms by which MTHFR677C>T increases risk. Therefore, MODEL-AD created a novel knock-in (KI) strain carrying the Mthfr677C>T allele on the C57BL/6J background (Mthfr677C>T) to characterize morphology and function perturbed by the variant. Consistent with human clinical data, Mthfr677C>T mice have reduced enzyme activity in the liver and elevated plasma homocysteine levels. MTHFR enzyme activity as well as critical metabolites in the folate and methionine cycles are reduced in the Mthfr677C>T brain. Mice showed reduced tissue perfusion in numerous brain regions by PET/CT as well as significantly reduced vascular density and increased GFAP-expressing astrocytes in frontal cortex. Electron microscopy revealed cerebrovascular damage including endothelial and pericyte apoptosis, reduced luminal size, and increased astrocyte and microglial presence in the microenvironment. Collectively, these data suggest critical perturbations to cerebrovascular function in Mthfr677C>T mice supporting its use as a model for preclinical studies of VCID.

genetics↗

A dietary vitamin B12 deficiency impairs motor function and changes neuronal survival and choline metabolism after ischemic stroke to the sensorimotor cortex in middle aged male and female mice

Nutrition is a modifiable risk factor for ischemic stroke. As people age their ability to absorb some nutrients decreases, a primary example is vitamin B12. Older individuals with a vitamin B12 deficiency are at a higher risk for ischemic stroke and have worse stroke outcome. However, the mechanisms through which these occur remain unknown. The aim of the study was to investigate the role of vitamin B12 deficiency in ischemic stroke outcome and mechanistic changes in a mouse model. Ten-month-old male and female mice were put on control or vitamin B12 deficient diets for 4-weeks prior to and after ischemic stroke to the sensorimotor cortex. Motor function was measured, and tissues were collected to assess potential mechanisms. All deficient mice had increased levels of total homocysteine in plasma and liver tissues. After ischemic stroke, deficient mice had impaired motor function compared to control mice. There was no difference between groups in lesion volume, however, there was an increase in total apoptosis within the ischemic region of brain tissue in male deficient mice. More neuronal survival was present in ischemic brain tissue of the deficient mice compared to controls. Additionally, there were changes in choline metabolites in ischemic brain tissue because of a vitamin B12 deficiency. The data presented in this study confirms that a vitamin B12 deficiency worsens stroke outcome in male and female mice. The mechanisms driving this change may be a result of neuronal survival and compensation in choline metabolism within the damaged brain tissue.

neuroscience↗