Insulin deficiency in type I diabetes may lead to cognitive impairment, cerebral atrophy and white matter abnormalities. We studied the impact of a novel delivery system using intranasal insulin (I-I) in a mouse model of type I diabetes (streptozotocin-induced) for direct targeting of pathological and cognitive deficits while avoiding potential adverse systemic effects. Daily I-I, subcutaneous insulin (S-I) or placebo in separate cohorts of diabetic and non-diabetic CD1 mice were delivered over 8 months of life. Radio-labelled insulin delivery revealed that I-I delivered more rapid and substantial insulin levels within the cerebrum with less systemic insulin detection when compared with S-I. I-I delivery slowed development of cognitive decline within weekly cognitive/behavioural testing, ameliorated monthly magnetic resonance imaging abnormalities, prevented quantitative morphological abnormalities in cerebrum, improved mouse mortality and reversed diabetes-mediated declines in mRNA and protein for phosphoinositide 3-kinase (PI3K)/Akt and for protein levels of the transcription factors cyclic AMP response element binding protein (CREB) and glycogen synthase kinase 3beta (GSK-3beta) within different cerebral regions. Although the murine diabetic brain was not subject to cellular loss, a diabetes-mediated loss of protein and mRNA for the synaptic elements synaptophysin and choline acetyltransferase was prevented with I-I delivery. As a mechanism of delivery, I-I accesses the brain readily and slows the development of diabetes-induced brain changes as compared to S-I delivery. This therapy and delivery mode, available in humans, may be of clinical utility for the prevention of pathological changes in the diabetic human brain.

No abstract

OBJECTIVEWe hypothesized that intranasal insulin (I-I) delivery targets the nervous system while avoiding potential adverse systemic effects when compared with subcutaneous insulin (S-I) for experimental streptozotocin-induced diabetic peripheral neuropathy (DPN).RESEARCH DESIGN AND METHODSI-I or S-I at 0.87 IU daily or placebo were delivered in separate cohorts of diabetic and nondiabetic CD1 mice during 8 months of diabetes. Radiolabeled insulin detection was used to compare delivery and biodistribution for I-I and S-I. Biweekly behavioral testing and monthly electrophysiological and quantitative studies assessed progression of DPN. At and before end point, morphometric analysis of DRG, peripheral nerve, distal epidermal innervation, and specific molecular markers were evaluated.RESULTSRadiolabeled I-I resulted in more rapid and concentrated delivery to the spinal cord and DRG with less systemic insulin exposure. When compared with S-I or intranasal placebo, I-I reduced overall mouse mortality and sensory loss while improving neuropathic pain and electrophysiological/morphological abnormalities in diabetic mice. I-I restored mRNA and protein levels of phosphoinositide 3-kinase/Akt, cyclic AMP response element–binding protein, and glycogen synthase kinase 3β to near normal levels within diabetic DRGs.CONCLUSIONSI-I slows the progression of experimental DPN in streptozotocin mice, avoids adverse effects associated with S-I treatment, and prolongs lifespan when compared with S-I. I-I may be a promising approach for the treatment of DPN.

Feasibility of eccentric overloading and neuromuscular electrical stimulation to improve muscle strength and muscle mass after treatment for head and neck cancer. SportRχiv.

Background Advanced lung cancer patients face significant physical and psychological burden leading to reduced physical function and quality of life. Separately, physical activity, nutrition, and palliative symptom management interventions have been shown to improve functioning in this population, however no study has combined all three in a multimodal intervention. Therefore, we assessed the feasibility of a multimodal physical activity, nutrition, and palliative symptom management intervention in advanced lung cancer. Methods Participants received an individually tailored 12-week intervention featuring in-person group-based exercise classes, at-home physical activity prescription, behaviour change education, and nutrition and palliative care consultations. Patients reported symptom burden, energy, and fatigue before and after each class. At baseline and post-intervention, symptom burden, quality of life, fatigue, physical activity, dietary intake, and physical function were assessed. Post-intervention interviews examined participant perspectives. Results The multimodal program was feasible, with 44% (10/23) recruitment, 75% (75/100) class attendance, 89% (8/9) nutrition and palliative consult attendance, and 85% (17/20) assessment completion. Of ten participants, 70% (7/10) completed the post-intervention follow-up. Participants perceived the intervention as feasible and valuable. Physical activity, symptom burden, and quality of life were maintained, while tiredness decreased significantly. Exercise classes prompted acute clinically meaningful reductions in fatigue, tiredness, depression, pain, and increases in energy and well-being. Conclusion A multimodal physical activity, nutrition, and palliative symptom management intervention is feasible and shows potential benefits on quality of life that warrant further investigation in a larger cohort trial. Trial registration NCT04575831, Registered 05 October 2020 – Retrospectively registered.