Administration of Intranasal Insulin During Cardiopulmonary Resuscitation Improves Neurological Outcomes After Cardiac Arrest

INTRODUCTION: Over 325,000 people die from cardiac arrest each year. Prognosis is poor and survivors typically experience persistent neurologic deficits. Currently, neuroprotective treatments to reduce brain injury in cardiac arrest survivors are limited and ineffective. This study evaluates the potential neuroprotection induced by high dose intranasal insulin (HD-IN-I) in a rodent model of asphyxial cardiac arrest. METHODS: Male Long Evans rats were block randomized to sham-operated controls or 8-minute asphyxial cardiac arrest treated with placebo or HD-IN-I at the onset of CPR. To investigate mechanism of action, hippocampi were collected 30 minutes post-ROSC and analyzed by Western blot for phosphorylation of Akt. To assess long-term functional outcomes, neurobehavioral evaluation was conducted using neurologic function scores daily and Barnes maze, Rotarod, and passive avoidance on days 7-10 post-ROSC. Histologic quantification of surviving hippocampal CA1 pyramidal neurons was also conducted. RESULTS: Hippocampal phospho-Akt/total Akt ratio increased 2-fold in the placebo group and 5.7-fold in HD-IN-I group relative to shams (p \u3c 0.05). Rats treated with HD-IN-I had significantly improved performance on Rotarod, Barnes maze, and passive avoidance (p \u3c 0.05). HD-IN-I had no significant effect on ROSC rate, 10-day survival, systemic glycemic response, or on the number of surviving CA1 pyramidal neurons compared to placebo treatment. DISCUSSION: This study is the first to demonstrate that HD-IN-I administered at the onset of CPR, causes phosphorylation of brain Akt and results in significant neuroprotection. This primary work strongly suggests that intranasal insulin could be the first highly effective neuroprotective treatment for cardiac arrest patients

Differential Strain-Dependent Ovarian and Metabolic Responses in a Mouse Model of PCOS

Several mouse models have been developed to study polycystic ovarian syndrome (PCOS), a leading cause of infertility in women. Treatment of mice with dihydrotestosterone (DHT) for 90-days causes ovarian and metabolic phenotypes similar to women with PCOS. We used this 90-day DHT treatment paradigm to investigate the variable incidence and heterogeneity in two inbred mouse strains, NOD/ShiLtJ and 129S1/SvlmJ. NOD mice naturally develop type 1 diabetes, and recent meta-analysis found increased androgen excess and PCOS in women with type 1 diabetes. 129S1 mice are commonly used in genetic manipulations. Both NOD and 129S1 DHT treated mice had early vaginal opening, increased anogenital distance and altered estrus cycles compared to control animals. Additionally, both NOD and 129S1 mice had reduced numbers of corpora lutea after DHT exposure, while NOD mice had decreased numbers of preantral follicles and 129S1 mice had reduced numbers of small antral follicles. NOD mice had increased body weight, decreased white adipocyte size, and improved glucose sensitivity in response to DHT, while 129S1 mice had increased body weight and white adipocyte size. NOD mice had increased expression of Adiponectin, Cidea, Srebp1a and Srebp1b and 129S1 mice had decreased Pparg in the white adipose tissues, while both NOD and 129S1 mice had increased expression of Glut4 and Prdm16 suggesting DHT may differentially affect glucose transport, thermogenesis, and lipid storage in white adipose tissue. DHT causes different ovarian and metabolic responses in NOD and 129S1 mice suggesting that strain differences may allow further elucidation of genetic contributions to PCOS