[Diabetic and non-diabetic neuropathies in patients with diabetes mellitus]

Rapamycin Ameliorates Cognitive Impairments and Alzheimer's Disease-Like Pathology with Restoring Mitochondrial Abnormality in the Hippocampus of Streptozotocin-Induced Diabetic Mice

Alzheimer's disease (AD) and diabetes mellitus (DM) share common pathophysiological findings, in particular, the mammalian target of rapamycin (mTOR) has been strongly implied to link to AD, while it also plays a key role in the insulin signaling pathway. However, the mechanism of how DM and AD is coupled remains elusive. In the present study, we found that streptozotocin (STZ)-induced DM mice significantly increased the levels P-mTOR Ser2448, P-p70S6K Thr389, P-tau Ser356 and Aβ levels (Aβ oligomer/monomer), as well as the levels of Drp1 and p-Drp1 S616 (mitochondrial fission proteins) are increased, whereas no change was found in the expression of Opa1, Mfn1 and Mfn2 (mitochondrial fusion proteins) compared with control mice. Moreover, the expression of 4-HNE and 8-OHdG showed an aberrant increase in the hippocampus of STZ-induced DM mice that is associated with a decreased capacity of spatial memory and a loss of synapses. Rapamycin, an inhibitor of mTOR, rescued the STZ-induced increases in mTOR/p70S6K activities, tau phosphorylation and Aβ levels, as well as mitochondria abnormality and cognitive impairment in mice. These findings imply that rapamycin prevents cognitive impairment and protects hippocampus neurons from AD-like pathology and mitochondrial abnormality, and also that rapamycin treatment could normalize these STZ-induced alterations by decreasing hippocampus mTOR/p70S6K hyperactivity.

['Point of no return' in diabetic neuropathies: a dangerous delusion]

Polyneuropathy in patients with diabetes mellitus is manifested by a lesion of peripheral sensory, motor and autonomic nervous system. Different severity of damage of sensory, motor and autonomic fibers in typical and atypical forms of diabetic polyneuropathy, requires a differentiated approach to therapy, but not the rejection of its implementation. In an interdisciplinary consensus, consultations are held with physicians from different regions of the Russian Federation, and modern methods of diagnosing and assessing the severity of diabetic polyneuropathies, which determine the algorithm for treating patients, are discussed.

[Specifics of diagnosis and treatment of diabetic polyneuropathy in elderly patients]

AIM

To study the specifics of diagnosis and treatment of diabetic polyneuropathy in elderly patients.

MATERIAL AND METHODS

Forty-two patients (22 men and 20 women, aged from 65 to 75 years) with diabetes mellitus type 2 and diabetic polyneuropathy were studied using the following psychometric scales: the Michigan Neuropathy Screening Instrument (MNSI), Neurological symptoms scale (NSS), Neuropathy Disability Score (NDS), the Numerical Rating Scale (NRS), Kaplan-Feinstein index (KFI), the Covi Anxiety Scale (COVI), the Recovery Locus of Control Scale (RLOC). Patients were divided into group 1 (n=24) treated with neuromultivit injections, along with standard treatment, and group 2 (n=18), which received standard treatment only. Patients were examined at baseline and one month after treatment.

RESULTS

In elderly patients, diabetic distal symmetric sensorimotor polyneuropathy of moderate severity was comorbid mostly with cardio-vascular disease. Pain syndrome was associated with anxiety and significant direct correlation between anxiety and pain intensity was found. The level of motivation towards recovery was significantly lower and correlated with COVI scores.

CONCLUSION

Injections of neuromultivit decrease the intensity of pain, improve the emotional state and increase the level of motivation towards recovery.