Hai Duc Nguyen, Ngoc Minh Hong Hoang, Won Hee Jo, Ju Ri Ham, Mi-Kyung Lee, Min Sun Kim
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引用次数: 13
Abstract
Introduction: Diabetes mellitus (DM) is a risk factor for Alzheimer's disease (AD). Increasing evidence indicates that the triggering receptor expressed on myeloid cells (TREM)-1 amplifies chronic inflammation, as well as the roles of prolactin (PRL) and metformin (MET) in tau hyperphosphorylation. However, the associations among TREM-1, tau hyperphosphorylation, PRL expression, and MET in DM remain unclear.
Methods: Streptozotocin was used to induce experimental DM in C57BL/6N mice. MET was orally administered at a dose of 400 mg/kg body weight for 6 weeks prior to hippocampal collection in DM mice. Various parameters pertaining to the TREM-1 pathway, tau hyperphosphorylation, PRL, and related factors were analyzed.
Results: Quantitative polymerase chain reaction and Western blot analysis demonstrated that the expression levels of TREM-1, DAP12, casp1, interleukin-1β, Cox2, inducible nitric oxide synthase, pituitary transcriptional factor-1 (Pit-1), and PRL were significantly increased in the hippocampus of DM mice; the expression levels of these pro-inflammatory mediators, PRL receptor (PRLR) short or long (PRLR-S and PRLR-L), and PRL regulatory element-binding (Preb) protein in DM mice treated with MET (DM + MET) were significantly decreased compared with those in control (CON) mice. The levels of p-Tau and glycogen synthase kinase-3 in the DM group were significantly higher than those in the CON group and significantly lower than those in the DM + MET group.
Conclusion: We confirmed the therapeutic potential of MET for both DM and neurodegeneration. Our findings shed new light on the effects of DM on the pathophysiology of AD via the TREM-1 pathway and PRL expression. Thus, an improved understanding of the TREM-1 pathway in hyperglycemic conditions, as well as PRL, Preb, Pit-1, PRLR-L, and PRLR-S gene expression in the liver, brain, and other sites, may help unravel the pathogenesis of insulin resistance and neurodegeneration.
期刊介绍:
The rapidly expanding area of research known as neuroimmunomodulation explores the way in which the nervous system interacts with the immune system via neural, hormonal, and paracrine actions. Encompassing both basic and clinical research, ''Neuroimmunomodulation'' reports on all aspects of these interactions. Basic investigations consider all neural and humoral networks from molecular genetics through cell regulation to integrative systems of the body. The journal also aims to clarify the basic mechanisms involved in the pathogenesis of the CNS pathology in AIDS patients and in various neurodegenerative diseases. Although primarily devoted to research articles, timely reviews are published on a regular basis.