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Godoy-Lugo, J. A.

Publications and source records attributed to Godoy-Lugo, J. A..

5 recordsLinked to original sources

Females Adapt to Dietary Protein Restriction on Enhanced Gut-Brain Axis during Aging

Growing evidence supports a critical role for the gut-brain axis in regulating metabolic health, inflammation, and cognitive function during aging. Age-associated gut dysbiosis has been linked to metabolic dysfunction and cognitive decline, with females exhibiting increased susceptibility to these age-related impairments. Diet is a major determinant of gut microbiome composition and function. Previous studies from our laboratory demonstrated that dietary protein restriction (DPR) induces fibroblast growth factor 21 (FGF21), improves metabolic health, and extends lifespan in male mice. However, the effects of DPR on the gut microbiome and associated health outcomes in aged female mice remain poorly understood. Female mice were assigned at 16 months of age to either a normal-protein (NP) or low-protein (LP) diet for 26 weeks. Metabolic assessments included food intake, fasting glucose concentrations, and glucose tolerance testing. Senescence-associated markers in mesenteric white adipose tissue (mWAT), fecal microbiome composition, and behavioral outcomes were evaluated to determine relationships among dietary protein intake, microbial communities, metabolic health, and cognitive function. Low-protein diet significantly improved metabolic health in aged female mice, as evidenced by improved glucose regulation. Microbiome analyses revealed increased abundance of Akkermansia at 17 months and Faecalibaculum in LP-fed animals at 22 months of age. More so, functional profiling and gene set enrichment analyses indicated enrichment of microbial pathways associated with membrane integrity and metal ion binding. Lastly, LP-fed female mice displayed improved memory performance at 22 months of age compared with age-matched NP-fed controls. Collectively, these findings demonstrate that DPR remodels the gut microbiome and improves metabolic and cognitive health in aged female mice. The observed microbial adaptations may contribute to the beneficial effects of DPR on aging-related physiology, highlighting the gut microbiome as a potential mediator of dietary interventions that promote healthy aging.

physiology↗

Induction of ferroptotic and amyloidogenic signatures linked to Alzheimers disease by chemically distinct air pollutants

Air pollution (AirP) exposure is associated with increased Alzheimers disease (AD) risk, yet AirP is chemically heterogeneous, complicating identification of shared pathogenic drivers. We examined acute cortical responses to two metal-rich AirP sources, diesel exhaust particles (DEP) and World Trade Center (WTC) dust, and compared them to woodsmoke (WS), a particulate exposure with low metal content. DEP and WTC elicited highly convergent transcriptional responses, sharing over 1200 differentially expressed genes linked to inflammation, ferroptosis, neuronal remodeling, and amyloid processing. These changes were accompanied by impaired antioxidant activity and increased lipid peroxidation within lipid rafts, a membrane microdomain critical for amyloid processing, resulting in increased A{beta} generation. In contrast, WS produced a distinct transcriptional signature and failed to induce ferroptotic priming or lipid peroxidation, consistent with its low metal composition. Together, these findings implicate metals as a shared driver linking diverse AirP exposures to amyloidogenic vulnerability and elevated AD risk. Graphical AbstractAcute AirP exposure converges on ferroptotic priming, amyloidogenic processing, and white-matter vulnerability. Acute exposure to metal-rich AirP, such as DEP or WTC introduces redox-active metals and particulate matter that promote lipid peroxidation, amyloidogenesis, and altered transcriptional regulation in the brain. AirP exposure engages xenobiotic metabolism pathways (AhR/ARNT), activates iron and heme handling through ferritinophagy (NCOA4) and heme oxygenase activity (HMOX1), and blunts lipid peroxide detoxification systems, including glutathione peroxidase 4 (GPx4), ferroptosis suppressor protein 1 (FSP1), and glutathione (GSH) synthesis. These changes promote ferroptotic priming and lipid raft oxidation, facilitating amyloid precursor protein (APP) processing by secretases (ADAM10, BACE1, {gamma}-secretase) and increasing amyloid-{beta} (A{beta}) generation. In parallel, transcriptional and cell-state remodeling involving neuronal and oligodendrocyte responses contribute to selective white-matter vulnerability, particularly within the corpus callosum. Together, these pathways provide a mechanistic framework linking acute AirP exposure to convergent oxidative, amyloidogenic, and microstructural changes relevant to Alzheimers disease pathology. O_FIG O_LINKSMALLFIG WIDTH=197 HEIGHT=200 SRC="FIGDIR/small/696601v1_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@3a22dcorg.highwire.dtl.DTLVardef@c6ae26org.highwire.dtl.DTLVardef@1d3412forg.highwire.dtl.DTLVardef@5cb011_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Down syndrome with Alzheimers disease brains have increased iron and associated lipid peroxidation consistent with ferroptosis

INTRODUCTIONCerebral microbleeds (MB) are associated with sporadic Alzheimers Disease (AD) and Down Syndrome with AD (DSAD). Higher MB iron may cause iron mediated lipid peroxidation. We hypothesize that amyloid deposition is linked to MB iron and that amyloid precursor protein (APP) triplication increases iron load and lipid peroxidation. METHODSPrefrontal cortex and cerebellum of cognitively normal (CTL), AD and DSAD ApoE3,3 carriers were examined for proteins that mediated iron metabolism, antioxidant response, and amyloid processing in lipid rafts. RESULTSIron was 2-fold higher in DSAD than CTL and AD. Iron storage proteins and lipid peroxidation were increased in prefrontal cortex, but not in the cerebellum. The glutathione synthesis protein GCLM was decreased by 50% in both AD and DSAD. Activity of lipid raft GPx4, responsible for membrane repair, was decreased by at least 30% in AD and DSAD. DISCUSSIONDSAD shows greater lipid peroxidation than AD consistent with greater MBs and iron load. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=189 HEIGHT=200 SRC="FIGDIR/small/636731v1_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@fd0d2aorg.highwire.dtl.DTLVardef@16b65d5org.highwire.dtl.DTLVardef@1eab2ddorg.highwire.dtl.DTLVardef@184e6d2_HPS_FORMAT_FIGEXP M_FIG C_FIG Cerebral microbleeds result in increased brain iron and lipid peroxidation in DSAD consistent with ferroptosis as reported for Alzheimers disease. A{beta}; beta-amyloid peptides, APP; amyloid precursor protein, GCLC; glutathione cysteine ligase catalytic subunit, GCLM; glutathione cysteine modifier subunit, GPx4; glutathione peroxidase 4, HNE; 4-hydroxynonenal. RESEARCH IN CONTEXTO_LISystematic Review: DS is associated with increased microbleeds and brain iron that may be mediated by increased APP from Trisomy 21. To assess potential links between amyloid and iron levels, we examined sporadic and DS with AD brains for amyloid processing and antioxidant enzyme defense in lipid rafts. We further compared DSAD with rare variants of DS: partial and mosaic T21. C_LIO_LIInterpretation: DSAD brains showed greater oxidation of lipid rafts where APP is processed than sporadic AD. Corresponding decreases in lipid raft antioxidant enzymes, despite increased total levels of these antioxidant enzymes, present a new mechanism for aberrant amyloid processing during AD. C_LIO_LIFuture Directions: Iron chelation therapies in combination with amyloid monoclonals may benefit DSAD. C_LI

neuroscience↗

Iron chelation by oral deferoxamine treatment decreased brain iron and iron signaling proteins

BackgroundDeferoxamine (DFO) and other iron chelators are clinically used for cancer and stroke. They may also be useful for Alzheimers disease (AD) to diminish iron from microbleeds. DFO may also stimulate antioxidant membrane repair which is impaired during AD. DFO, and other chelators do enter the brain despite some contrary reports. ObjectiveLow dose, oral DFO was given in lab chow to wildtype (WT) C57BL/6 mice to evaluate potential impact on iron levels, iron-signaling and storage proteins, and amyloid precursor protein (APP) and processing enzymes. Young WT mice do not have microbleeds or disrupted blood-brain barrier of AD mice. MethodsIron was measured by MRI and chemically after two weeks of dietary DFO. Cerebral cortex was examined for changes in iron metabolism, antioxidant signaling, and APP processing by Western blot. ResultsDFO decreased brain iron by 18% (MRI) and decreased seven major proteins that mediate iron metabolism by at least 25%. The iron storage proteins ferritin light and heavy chain decreased by at least 30%. APP and secretase enzymes also decreased by 30%. ConclusionsWT mice respond to DFO with decreased APP, amyloid processing enzymes, and antioxidant repair. Potential DFO treatment for early-stage AD by DFO should consider the benefits of lowered APP and secretase enzymes.

neuroscience↗

Alzheimer's Disease associations of ferritin and glutathione with oxidative damage and neuronal loss

ABSTRACTIron-mediated cell death (ferroptosis) is a proposed mechanism of Alzheimers disease (AD) pathology. While iron is essential for basic biological functions, its reactivity generates oxidants which contribute to cell damage and death. To further resolve mechanisms of iron-mediated toxicity in AD, we analyzed postmortem human brain and ApoEFAD mice. AD brains had decreased antioxidant enzymes, including those mediated by glutathione (GSH). Subcellular analyses of AD brains showed greater oxidative damage and lower antioxidant enzymes in lipid rafts, the site of amyloid processing, than in the non-raft membrane fraction. ApoE4 carriers had lower lipid raft yield with greater membrane oxidation. The hypothesized role of iron to AD pathology was tested in ApoEFAD mice by iron chelation with deferoxamine, which decreased fibrillar amyloid and lipid peroxidation, together with increased GSH-mediated antioxidants. These novel molecular pathways in iron mediated damage during AD. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=173 HEIGHT=200 SRC="FIGDIR/small/534324v3_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@1a28ddborg.highwire.dtl.DTLVardef@10f57f7org.highwire.dtl.DTLVardef@583c8corg.highwire.dtl.DTLVardef@ef45f9_HPS_FORMAT_FIGEXP M_FIG C_FIG Hypothesis: AD brain lipid peroxidation is driven by increased brain iron and decreased antioxidant defenses. Schema shows proteins that mediate iron metabolism in relation to lipid peroxidation (HNE) and antioxidant defenses in prefrontal cortex. AD-associated increase (red), decrease (blue), or no change (grey), relative to cognitively normal elderly controls. A{beta}; amyloid beta, ALDH2; alcohol dehydrogenase, APP; amyloid precursor protein, DMT1; divalent metal transporter 1; FPN, ferroportin; FSP1, ferroptosis suppressor protein 1, which requires the quinol cycle to attenuate lipid peroxidation; FTH1, ferritin heavy chain; FTL; ferritin light chain; GCLC, glutathione cysteine ligase catalytic subunit; GCLM, glutathione cysteine ligase modulator; GPx4, glutathione peroxidase 4; GSH, glutathione; GSSG, glutathione disulfide; GSTA4, glutathione S-transferase A4; HMOX; heme oxygenase; IRP, iron regulatory protein; LAT1, large neutral amino acid transporter 1; LOOH, Lipid hydroperoxides; Nrf2, Nuclear factor erythroid 2-related factor 2; Prdx6, peroxiredoxin 6; TF, transferrin, TfR; Transferrin receptor; xCT, cysteine-glutamate antiporter.

neuroscience↗