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Putzolu, A.

Publications and source records attributed to Putzolu, A..

2 recordsLinked to original sources

THERAPEUTIC EFFECTS OF AN INSULIN-LIKE GROWTH FACTOR I SENSITIZER IN TRAUMATIC BRAIN INJURY

Traumatic brain injury (TBI) is a condition of high incidence worldwide, but remains mostly undertreated. Previous observations in preclinical studies pointed to a beneficial effect of insulin-like growth factor 1 (IGF-1) in TBI. As brain injury is associated to loss of IGF-1 sensitivity, we tested the therapeutic potential of AIK3a305 (AIK3), a novel IGF-1 sensitizer. Twenty-four hours after mild TBI induced by controlled impact, mice received daily intraperitoneal injections of AIK3 during 4 weeks. We found that TBI-associated sensorimotor disturbances measured with the adhesive-removal test were reverted by AIK3 treatment. In addition, neurological and cognitive disturbances measured by the neurological severity score and Y maze respectively, were also ameliorated by treatment with the IGF-1 sensitizer, whereas increased anxiety after mild TBI was also normalized by AIK3. Circulating levels of IGF-1 were increased after AIK3 treatment in TBI mice, while serum IL-6 levels, a biomarker of inflammation associated to TBI were similar to control mice treated with AIK3. Transcriptomic analysis determined that treatment with AIK3 widely affected gene expression in TBI brains, showing a general reduction in both up- and down-regulated genes. Collectively, these data support the use of IGF-1 sensitizers such as AIK3 for treatment of TBI.

neuroscience↗

INFLUENCE OF LIFESTYLE ON BRAIN SENSITIVITY TO CIRCULATING INSULIN-LIKE GROWTH FACTOR 1

Life style conditions such as social relationships and diet impinge on mood homeostasis, a mechanism that becomes dysregulated in high-incidence mental illnesses such as depression or Alzheimers dementia (AD). Since insulin-like growth factor 1 (IGF-1) modulates mood and its blood levels are altered both in AD and in affective disorders, we investigated whether its activity was altered in the brain of mice submitted to isolation or fed with a high-fat diet (HFD). As in humans, both life style conditions increased anxiety and depression-like behavior. Significantly, both life style conditions abrogated neuronal responses to systemic IGF-1. Thus, enhanced neuronal activity in response to intraperitoneal IGF-1, as determined by Ca++ fiber-photometry in the prefrontal cortex, was lost in isolated or HFD-fed mice. However, only the latter had elevated serum IGF-1 levels. These findings suggest that loss of brain IGF-1 input may contribute to mood disturbances observed in lonely and obese subjects. Furthermore, they provide additional insight into the heightened risk of depression and Alzheimers disease associated with these conditions. Importantly, since the reduction of IGF-1 activity in the brain is not consistently mirrored by its serum levels, serum measurements do not reliably reflect brain IGF-1 activity.

neuroscience↗