Lycium Barbarum Polysaccharides Improves Cognitive Functions in ICV-STZ-Induced Alzheimer's Disease Mice Model by Improving the Synaptic Structural Plasticity and Regulating IRS1/PI3K/AKT Signaling Pathway.

Lycium barbarum polysaccharide (LBP) have a certain curative effect on hypoglycemic and neuroprotective effects, but the specific mechanism is unclear and needs to be further explored. This study aimed to clarify the mechanisms of LBP in the treatment of ICV-STZ mice model of AD from the perspectives of insulin resistance, IRS1/PI3K/AKT signaling pathway, and synaptic protein expression. We used male C57BL/6J mice injected with STZ (3 mg/kg) in the lateral ventricle as an AD model. After treatment with LBP, the learning and memory abilities of ICV-STZ mice were enhanced, and the pathological changes in brain tissue were alleviated. LBP can regulate the expression of proteins related to the IRS1/PI3K/AKT signaling pathway and thereby reducing Aß deposition and tau protein phosphorylation in the brain of ICV-STZ mice. In addition, LBP also can up-regulate the expression of synaptic proteins. The results indicated that LBP played a neuroprotective role by regulating the IRS1/PI3K/AKT pathway, inhibiting tau protein hyperphosphorylation and improving the expression levels of synapse-related proteins.

[Etiologies and clinical features of 19 cases with bilateral acute sensorineural hearing loss].

OBJECTIVE: To investigate the etiologies and clinical features for bilateral acute sensorineural hearing loss (bi-ASNHL). METHODS: The clinical data of 19 cases presenting with bi-ASNHL were retrospectively analyzed, including the clinical features, systemic examinations, laboratory examinations, audiology and radiology results, as well as the prognosis. RESULTS: There were 15 non-otologic diseases in 19 patients, accounting for 78.9% of the total cases, most of which were disorders with multisystem and multi-organ disorder. The central nervous system diseases including fungal meningitis, tuberculous meningitis, and viral encephalitis in 3 patients. The clinical features of deafness were bilateral, progressive, accompanied with fever, headache, dizziness, nausea, vomiting and change of mental status. There was a decrease in speech recognition score (SRS), and speech recognition threshold (SRT) was obviously inferior to pure tone average (PTA) disproportionally. Diseases of immune system including antineural cytoplasmic antibody (ANCA)-associated systemic vasculitis (AASV), relapsing polychondritis (RP), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE) in 5 patients. They showed the characteristics of bilateral, progressive and simultaneous autoimmune disease. Hematological and endocrine system diseases including diabetes mellitus, leukemia, and thyroid hypofunction in 5 patients. The deafness had the characteristics of symmetry and progressivity. Otologic diseases including large vestibular aqueduct syndrome (LVAS) and sudden sensorineural hearing loss (SSNHL) in 4 patients; Drug-induced sensorineural deafness happened in 2 patients. After the treatment aimed at the causes, 1 case was cured, 3 patients were markedly effective, 7 patients were effective, and 8 patients were ineffective(including dead and refusal cases), with a total effective rate of 57.9%. CONCLUSIONS: The most of bi-ASNHL cases are often associated with systemic diseases. Clinicians should analyze the history and clinical characteristics in detail, and complete specific laboratory examinations, audiology and imaging examinations in order to reveal the causative diseases. It should be treated aimed at the etiology.