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Rosenberg, L.

Publications and source records attributed to Rosenberg, L..

2 recordsLinked to original sources

Ketogenic Diet Enhances Cognitive-Behavioral Function and Hippocampal Neurogenesis While Attenuating Amyloid Pathology in Tg-SwDI Mice

The ketogenic diet (KD), characterized by high-fat, low-carbohydrate, and moderate protein intake, has gained attention for its therapeutic potential in patients with neurodegenerative diseases, including Alzheimers disease. Studies in Alzheimers rodent models report that KD and/or ketogenic supplements attenuate cognitive-behavioral impairments, neuroinflammation, amyloid-beta plaques and tau pathology. However, it is unknown whether KD can similarly benefit individuals with cerebral amyloid angiopathy (CAA), a prevalent condition in which amyloid accumulates in cerebral vessels. CAA is highly comorbid in patients with Alzheimers and, on its own, increases the risk of stroke, cognitive impairment, and dementia, yet no effective treatments currently exist. The objective of this study was to determine whether KD can improve cognitive-behavioral and neuropathological outcomes in a mouse model with CAA. Male Tg-SwDI mice were fed either a standard chow or KD from 3.5 to 7.5 months of age. Following [~]3 months of dietary intervention, glucose and ketone-body levels were assessed, then mice underwent a battery of behavioral tests to evaluate locomotor activity, anxiety-related behaviors, and cognition. Immunohistochemistry was performed to assess amyloid pathology, vascular density, neuroinflammation, white matter integrity, and hippocampal neurogenesis. In addition to KD inducing nutritional ketosis and achieving metabolic benefits, mice on KD exhibited increased activity, enhanced spatial learning and memory, and a trend toward improved spatial working memory. These cognitive benefits were accompanied by an attenuation of amyloid pathology and increased hippocampal neurogenesis. These findings suggest that a ketogenic diet may be safe and effective in Alzheimers and dementia patients with CAA.

neuroscience↗

Oxygen carrying nanoemulsions and respiratory hyperoxia eliminate tumor hypoxia-induced suppression and improve cancer immunotherapy

Hypoxia-HIF-1-driven immunosuppressive transcription and cAMP-elevating signaling through A2A-adenosine receptors (A2AR) represent a major tumor-protecting pathway that enables immune evasion. Recent promising clinical outcomes due to the blockade of the adenosine-generating enzyme CD73 and A2AR in patients refractory to all other therapies have confirmed the importance of targeting hypoxia-adenosinergic signaling. We report a novel and feasible approach to target the upstream stage of hypoxia-adenosinergic immunosuppression using an oxygen-carrying nanoemulsion (perfluorocarbon blood substitute). It is shown that oxygenation agent therapy i) eliminates tumor hypoxia, ii) improves efficacy of endogenously developed and adoptively transferred T cells, and thereby iii) promotes regression of tumors in different anatomical locations. We show that both T cells and NK cells avoid hypoxic tumor areas and that reversal of hypoxia by oxygenation agent therapy increases intratumoral infiltration of activated T cells and NK cells due to re-programming of the tumor microenvironment (TME). Thus, repurposing oxygenation agents in combination with supplemental oxygen may improve current cancer immunotherapies by preventing hypoxia-adenosinergic suppression, promoting immune cell infiltration and enhancing effector responses. These data also suggest that pretreating patients with oxygenation agent therapy may reprogram the TME from immune-suppressive to immune-permissive prior to adoptive cell therapy, or other forms of immunotherapy. SummaryOxygen delivering nanoemulsions and respiratory hyperoxia address limitations of blood vessel-mediated tumor oxygenation and promote anti-tumor immune responses to enhance immunotherapy.

immunology↗