Hot Spots for the Use of Intranasal Insulin: Cerebral Ischemia, Brain Injury, Diabetes Mellitus, Endocrine Disorders and Postoperative Delirium

A decrease in the activity of the insulin signaling system of the brain, due to both central insulin resistance and insulin deficiency, leads to neurodegeneration and impaired regulation of appetite, metabolism, endocrine functions. This is due to the neuroprotective properties of brain insulin and its leading role in maintaining glucose homeostasis in the brain, as well as in the regulation of the brain signaling network responsible for the functioning of the nervous, endocrine, and other systems. One of the approaches to restore the activity of the insulin system of the brain is the use of intranasally administered insulin (INI). Currently, INI is being considered as a promising drug to treat Alzheimer's disease and mild cognitive impairment. The clinical application of INI is being developed for the treatment of other neurodegenerative diseases and improve cognitive abilities in stress, overwork, and depression. At the same time, much attention has recently been paid to the prospects of using INI for the treatment of cerebral ischemia, traumatic brain injuries, and postoperative delirium (after anesthesia), as well as diabetes mellitus and its complications, including dysfunctions in the gonadal and thyroid axes. This review is devoted to the prospects and current trends in the use of INI for the treatment of these diseases, which, although differing in etiology and pathogenesis, are characterized by impaired insulin signaling in the brain.

IMMUNE-INFLAMMATORY-ENDOCRINE REGULATION DISORDERS IN CHILDREN WITH CORONAVIRUS INFECTION

OBJECTIVE

The aim: To study the of homeostasis links desorder and indicators imbalance in children with Coronavirus infection.

PATIENTS AND METHODS

Materials and methods: A clinical and laboratory study was conducted in children (50 persons) with Coronavirus infection. The children were used outpatient treatment.

RESULTS

Results: It was found that Direct bilirubin was increased in 3 times (10.55±7.67 vs. 3.63±0.49 μmol/l, p<0.01), Alanine aminotransferase - in 1.7 times (37,02±20.53 vs. 21.90±1.82 IU/l, p<0.01). An levels increassng of Ig G - in 12.3 times, Ig E - in 4.6 times, Ig M - in 3.4 times was observed. The CRP level was increased in 3.1 times (8.76 ± 2.16 vs. 2.54 ± 0.53 mg/l, p< 0.01), C-peptide (4.65±1.67 vs. 1.23±0.08 ng/ml, p<0.01) - in 3.8 times. Negative correlations of T3 with Procalcitonin (r=-0.30) and Creatinine (r=-34) were revealed. T4 values are correlated with Total cholesterol (r=-0.65) and Creatinine (r=0.29). Leptin was presented positive correlations with Alanine aminotransferase (r=0.48) and with C-peptide (r=0.39).

CONCLUSION

Conclusions: There was an increase in the Ig G levels in 12.3 times, Ig E - in 4.6 times, and the Ig M level - in 3.4 times. The Thyroid stimulating hormone level was significantly lower (in 4.7 times). An increase in the C-reactive protein levels (in 3.1 times) and C-peptide (in 3.8 times) was observed. It should be noted that the strongest negative correlation between T4 and Total cholesterol (r=-0.65) and the highest positive correlation between Leptin and Alanine aminotransferase (r=0.48) and C-peptide (r=0. 39).

Intranasal Administration of Proinsulin C-Peptide Enhances the Stimulating Effect of Insulin on Insulin System Activity in the Hypothalamus of Diabetic Rats

In type 1 diabetes mellitus, the levels of insulin and C-peptide decrease at the periphery and in CNS. C-peptide potentiates the regulatory effects of insulin. We studied the effects of single and repeated (over 7 days) individual and combined nasal administration of C-peptide (10 μg/day) and insulin (20 μg/day) on activity of Akt kinase and kinase-3β-glycogen synthase (GSK3β), the components of 3-phosphoinositide pathway, in the hypothalamus of intact rats and rats with mild streptozotocin-induced type 1 diabetes mellitus. Phosphorylation of Akt kinase at Thr³⁰⁸ and Ser⁴⁷³ (stimulation) and GSK3β at Ser⁹ (inhibition) was evaluated. In diabetes, phosphorylation of Akt kinase and, to a lesser extent, GSK3β, is reduced. A single injection of insulin or C-peptide and insulin increased this process. Long-term combined treatment with C-peptide and insulin normalized activity of Akt kinase and GSK3β in diabetic rats, treatment with insulin alone produced less pronounced effect; monotherapy with C-peptide was ineffective. Intranasal co-administration of C-peptide and insulin effectively stimulates the insulin system in the hypothalamus that is weakened at diabetes mellitus type 1, which can be used in the treatment of this disease.

Novel Formulations of C-Peptide with Long-Acting Therapeutic Potential for Treatment of Diabetic Complications

The development and application of novel nanospheres based on cationic and anionic random amphiphilic polypeptides with prolonged stability were proposed. The random copolymers, e.g., poly(l-lysine-co-d-phenylalanine) (P(Lys-co-dPhe)) and poly(l-glutamic acid-co-d-phenylalanine) (P(Glu-co-dPhe)), with different amount of hydrophilic and hydrophobic monomers were synthesized. The polypeptides obtained were able to self-assemble into nanospheres. Such characteristics as size, PDI and ζ-potential of the nanospheres were determined, as well as their dependence on pH was also studied. Additionally, the investigation of their biodegradability and cytotoxicity was performed. The prolonged stability of nanospheres was achieved via introduction of d-amino acids into the polypeptide structure. The cytotoxicity of nanospheres obtained was tested using HEK-293 cells. It was proved that no cytotoxicity up to the concentration of 500 µg/mL was observed. C-peptide delivery systems were realized in two ways: (1) peptide immobilization on the surface of P(Glu-co-dPhe) nanospheres; and (2) peptide encapsulation into P(Lys-co-dPhe) systems. The immobilization capacity and the dependence of C-peptide encapsulation efficiency, as well as maximal loading capacity, on initial drug concentration was studied. The kinetic of drug release was studied at model physiological conditions. Novel formulations of a long-acting C-peptide exhibited their effect ex vivo by increasing activity of erythrocyte Na⁺/K⁺-adenosine triphosphatase.