β-Glucan from Lentinula edodes prevents cognitive impairments in high-fat diet-induced obese mice: involvement of colon-brain axis

Abstract

Background Long-term high fat (HF) diet intake can cause neuroinflammation and cognitive decline through the gut-brain axis. (1, 3)/(1, 6)-β-glucan, an edible polysaccharide isolated from medical mushroom, Lentinula edodes (L. edodes), has the potential to remodel gut microbiota. However, the effects of L. edodes derived β-glucan against HF diet-induced neuroinflammation and cognitive decline remain unknown. This study aimed to evaluate the neuroprotective effect and mechanism of dietary L edodes β-glucan supplementation against the obesity-associated cognitive decline in mice fed by a HF diet. Methods C57BL/6J male mice were fed with either a lab chow (LC), HF or HF with L. edodes β-glucan supplementation diets for 7 days (short-term) or 15 weeks (long-term). Cognitive behavior was examined; blood, cecum content, colon and brain were collected to evaluate metabolic parameters, endotoxin, gut microbiota, colon, and brain pathology. Results We reported that short-term and long-term L. edodes β-glucan supplementation prevented the gut microbial composition shift induced by the HF diet. Long-term L. edodes β-glucan supplementation prevented the HF diet-induced recognition memory impairment assessed by behavioral tests (the temporal order memory, novel object recognition and Y-maze tests). In the prefrontal cortex and hippocampus, the β-glucan supplementation ameliorated the alteration of synaptic ultrastructure, neuroinflammation and brain-derived neurotrophic factor (BDNF) deficits induced by HF diet. Furthermore, the β-glucan supplementation increased the mucosal thickness, upregulated the expression of tight junction protein occludin, decreased the plasma LPS level, and inhibited the proinflammatory macrophage accumulation in the colon of mice fed by HF diet. Conclusions This study revealed that L. edodes β-glucan prevents cognitive impairments induced by the HF diet, which may occur via colon-brain axis improvement. The finding suggested that dietary L. edodes β-glucan supplementation may be an effective nutritional strategy to prevent obesity-associated cognitive decline.

Enhanced Expression of Thaumatin-like Protein Gene (LeTLP1) Endows Resistance to Trichoderma atroviride in Lentinula edodes

“…The nutritional compounds and pharmacological properties of Lentinula edodes are beneficial to human health [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. Unfortunately, L. edodes is heavily attacked by Trichoderma spp., which compete for limited resources and space for mycelial growth, and it harms the yield and quality of shiitake cultivation [ 12 , 16 , 17 , 39 , 40 ].…”

“…Lentinula edodes (also known as Xiang Gu or shiitake), a widely cultivated edible mushroom, is famous for its nutritional properties and pharmacological effects, such as its hypocholesterolemic, anti-inflammatory, antitumor, and neuroprotective effects [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. The cultivation, production, and consumption of shiitake are important nowadays not only in Asian countries but also in western countries.…”

Parasite-Derived Excretory-Secretory Products Alleviate Gut Microbiota Dysbiosis and Improve Cognitive Impairment Induced by a High-Fat Diet

“…The novel object recognition test (ORT) was performed based on methods previously described ( 10 , 41 , 42 ). Briefly, there are three stages in the ORT.…”

“…The temporal order memory test was performed based on methods previously described ( 41 , 42 ). In brief, the experiment comprised two sample trials and one test trial with an inter-trial interval of 60 min between each trial.…”

Maintaining the Balance of Intestinal Flora through the Diet: Effective Prevention of Illness

“…For instance, many Parkinson's disease patients are accompanied by gastrointestinal symptoms such as gastrointestinal peristalsis, loss of appetite, and constipation [7]. The behavioral changes caused by a high-fat diet may be due to gut microbiota, which in turn alter cognitive capacity [8].…”