![]() Therefore, in the current study, we investigated whether doenjang and steamed soybean attenuate neuroinflammation and neurodegenerative characteristics in the cortex and hippocampus of mice fed an HF diet.Īnimal studies were approved by the Chungbuk National University Institutional Animal Care and Use Committee (CBNUA-636-13-01) and were described previously. Previously, we reported that the anti-oxidative stress and anti-inflammatory effects observed in adipose tissues of mice fed an HF diet containing doenjang were more potent than those in mice fed an HF diet containing steamed soybean. In addition to isoflavone, soybean contains a variety of other biologically active compounds, including small peptides, soyasaponins, and phenolic acids. Meanwhile, glycosylated isoflavone converts into aglycones with greater anti-obesity and anti-diabetic activities. In doenjang, a traditional Korean fermented soybean paste, the qualitative and quantitative composition of soybean components are significantly changed by enzymatic processes during fermentation. Others have reported that isoflavone has recovered the cognition deficit induced in Aβ-injected rats, in the mice model of Parkinson’s disease, and in streptozotocin-induced diabetic mice. In addition, we have reported the neuroprotective effect of genistein against endoplasmic reticulum (ER) stress-mediated neurotoxicity in SH-SY5Y neuroblastoma cells. Our previous studies reported that genistein significantly inhibited inflammation in the liver of db/db mice fed a methionine-choline-deficient diet and prevented NAFLD and neurodegeneration of ApoE knock-out mice fed a high-fat (HF) diet. ![]() Physiologically relevant levels of isoflavone are shown to mimic beneficial effects of 17β-estradiol on the regulation of neuronal viability, β-amyloid peptide (Aβ) accumulation, and tau hyperphosphorylation. The absorption of aglycones is faster and more extensive than that of the glycosides therefore, isoflavone aglycone-rich products may provide additional health benefits over glucoside-rich products. In soybean and soy foods, isoflavones are contained in either aglycones, such as genistein, daidzein, and glycitein, or their respective β-glycosides, such as genistin, daidzin, and glycitin. Soybean and soy products are a particularly rich source of isoflavone with antioxidant and phytoestrogenic activities, which contribute to their beneficial effects on lipid metabolism, bone development, and cardiovascular and central nervous systems. Because of high metabolic rates of oxygen consumption and high levels of polyunsaturated fatty acids, neurons are known to be more susceptible to oxidative stress than other organs. Mechanistically, obesity-related neuronal stress and neuroinflammation was attributed to disruption of the blood-brain barrier, infiltration of immune cells, and activation of microglial cells. Due to the possible cross-talk between peripheral tissues and the brain, chronic inflammation and insulin resistance may play important roles in inducing brain dysfunction such as altered synaptic plasticity and cognitive impairment. Furthermore, accumulating evidence suggest that obesity is causally linked to neurodegenerative diseases. Obesity is considered as a major risk factor for the development of type 2 diabetes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular disease. These results suggest that bioactive compounds produced during the fermentation and aging of soybean may be involved in the enhanced neuroprotective effects of doenjang. Overall, doenjang was more effective than steamed soybean in suppressing neuroinflammation and neurodegeneration in mice fed an HF diet. Furthermore, doenjang consumption reduced tau hyperphosphorylation induced by HF feeding. Dietary doenjang reduced β-amyloid peptide (Aβ) levels by regulating gene expressions involved in Aβ production and degradation. Contents of oxidative metabolites and mRNA levels of oxidative stress- and neuroinflammation-related genes were lower in the DJ group compared to the HF group. ![]() Accordingly, we observed higher cell proliferation and neurotrophic factor mRNA levels in the DJ group. Doenjang consumption alleviated hippocampal neuronal loss, which was increased by the HF diet. C57BL/6J mice were fed a low-fat diet, an HF diet, an HF-containing steamed soybean diet, or an HF-containing doenjang (DJ) diet for 11 weeks. Because fermentation of soybean increases contents of various bioactive compounds with anti-obesity and anti-diabetic activities, we investigated the protective effect of doenjang, a Korean traditional fermented soybean paste, against neuroinflammation and neurodegeneration in the cortex and hippocampus of mice fed a high-fat (HF) diet. Obesity is considered a risk factor for neurodegeneration.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |