Gut microbiota modulates the inflammatory response and cognitive impairment induced by sleep deprivation.

Sleep deprivation (SD) is increasingly common in modern society, which can lead to the dysregulation of inflammatory responses and cognitive impairment, but the mechanisms remain unclear. Emerging evidence suggests that gut microbiota plays a critical role in the pathogenesis and development of inflammatory and psychiatric diseases, possibly via gut microbiota-brain interactions and neuroinflammation. The present study investigated the impact of SD on gut microbiota composition and explored whether alterations of the gut microbiota play a causal role in chronic inflammatory states and cognitive impairment that are induced by SD. We found that SD-induced gut dysbiosis, inflammatory responses, and cognitive impairment in humans. Moreover, the absence of the gut microbiota suppressed inflammatory response and cognitive impairment induced by SD in germ-free (GF) mice. Transplantation of the "SD microbiota" into GF mice activated the Toll-like receptor 4/nuclear factor-κB signaling pathway and impaired cognitive function in the recipient mice. Mice that harbored "SD microbiota" also exhibited increases in neuroinflammation and microglial activity in the hippocampus and medial prefrontal cortex. These findings indicate that gut dysbiosis contributes to both peripheral and central inflammatory processes and cognitive deficits that are induced by SD, which may open avenues for potential interventions that can relieve the detrimental consequences of sleep loss.

Effect of surgery-induced acute muscle wasting on postoperative outcomes and quality of life.

BACKGROUND: Gastrectomy results in a significant loss of body composition in the long term, but the acute skeletal muscle wasting after gastrectomy has been rarely investigated. Moreover, the association between postoperative muscle wasting and quality of life (QOL) has never been reported. In the present study, we aimed to investigate the risk factors for acute muscle wasting after gastric cancer surgery and its effect on QOL and short-term postoperative outcomes. METHODS: We conducted a prospective study of patients who underwent curative gastrectomy for gastric cancer between June 2015 and December 2015. Skeletal muscle mass was measured by computed tomography within 1 month before and 1 week after surgery. QOL was assessed 1, 3, and 6 months postoperatively. Univariate and multivariate analyses were performed to identify the risk factors for clinically relevant muscle wasting (muscle wasting ≥10%). RESULTS: A total of 110 patients were included, in which 35 patients had muscle wasting ≥10% within 1 week after surgery. Age ≥65 years and diabetes were independent risk factors for muscle wasting ≥10%. Patients with muscle wasting ≥10% had a poorer QOL in terms of fatigue and physical functioning at 1 and 3 months postoperatively, as well as a higher incidence of postoperative complications, a higher incidence of handgrip strength reduction ≥10%, longer hospital stays, and higher costs. CONCLUSIONS: Age ≥65 years and diabetes were independently associated with clinically relevant muscle wasting within 1 week after gastric cancer surgery. Clinically relevant muscle wasting was associated with a poorer QOL and short-term outcomes after surgery.

Alterations of the Gut Microbiota in Response to Total Sleep Deprivation and Recovery Sleep in Rats.

INTRODUCTION: Accumulating evidence suggests that both sleep loss and gut dysbiosis can lead to metabolic disorders. However, less is known about the impact of total sleep deprivation (SD) and sleep recovery on the composition, function, and metabolic dynamics of the gut microbiota. METHODS: Specific-pathogen free Sprague-Dawley rats were subjected to 48 h of SD with gentle handling and then allowed to recover for 1 week. Taxonomic profiles of fecal microbiota were obtained at baseline, 24 h of SD, 48 h of SD, and 1 week of recovery. We used 16S rRNA gene sequencing to analyze the gut microbial composition and function and further characterize microbiota-derived metabolites in rats. RESULTS: The microbiota composition analysis revealed that gut microbial composition and metabolites did not change in the rats after 24 h of SD but were significantly altered after 48 h of SD. These changes were reversible after 1 week of sleep recovery. A functional analysis was performed based on Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations, indicating that 19 KEGG pathways were significantly altered in the gut microbiota in SD rats. These functional changes occurred within 24 h of SD, were more apparent after 48 h of SD, and did not fully recover after 1 week of sleep recovery. CONCLUSION: These results indicate that acute total SD leads to significant compositional and functional changes in the gut microbiota, and these changes are reversible.

Diurnal rhythm disruptions induced by chronic unpredictable stress relate to depression-like behaviors in rats.

The relationship between circadian rhythms and mood disorders has been established. Circadian dysregulations are believed to exacerbate the severity of mood disorders and vice versa. Although many studies on diurnal changes of clock genes in animal model of depression have been performed from the RNA level, only a few studies have been carried out from the protein level. In this study, we investigated the diurnal changes induced by chronic unpredictable stress (CUS) using free-running wheel test and Western Blotting (WB). Besides, we examined the depression-like behaviors of rats by sucrose preference test (SPT) and forced swim test (FST). We found that CUS induced significant reductions in the quantity of free-running wheel activity and rhythmic disruptions of clock proteins in hippocampus. Furthermore, we found that the amplitude of PER1 in CA1 was positively related to the severity of depression-like behaviors. These results suggest that CUS results in both changes in diurnal rhythms and in depression-like behaviors and that it is suggested that these changes are related.

Retraction notice to "Diurnal rhythm disruptions induced by chronic unpredictable stress relate to depression-like behaviors in rats" [Pharmacol. Biochem. Behav. 194 (2020) 172939].

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor because of serious doubts regarding the data on melatonin levels. The authors used a melatonin ELISA kit that was not fit for purpose, resulting in data showing peak secretion of this hormone occurring in the middle of the light period, which does not make any physiological sense since melatonin is only produced during darkness.

Diurnal rhythm disruptions induced by chronic unpredictable stress relate to depression-like behaviors in rats.

The relationship between circadian rhythms and mood disorders has been established, circadian dysregulations are believed to exacerbate the severity of mood disorders and vice versa. Although many studies on diurnal changes of clock genes in animal model of depression have been performed from the RNA level, only a few studies have been carried out from the protein level. In this study, we investigated the diurnal changes induced by chronic unpredictable stress (CUS) using various methods, including free-running wheel test, enzyme-linked immunosorbent assay (ELISA) and Western Blotting (WB). Besides, we examined the depression-like behaviors of rats by sucrose preference test (SPT) and forced swim test (FST). We found that CUS induced significant reductions in the quantity of free-running wheel activity and the amplitude of melatonin secretion rhythm. We also found that CUS induced rhythmic disruptions of clock proteins in hippocampus. Furthermore, we found that the amplitude of PER1 in CA1 was positively related to the severity of depression-like behaviors. These results suggest that stress results in both changes in circadian rhythms and in depression-like behaviors and that it is suggested that these changes are related.

Effect of nutritional risk on short-term outcomes after laparoscopic-assisted gastrectomy: a prospective study from two centers.

BACKGROUND/AIM: The aim of this prospective double-center study was to explore the effect of nutritional risk on short-term outcomes in the patients who had gastric cancer and underwent a laparoscopic-assisted gastrectomy. PATIENTS AND METHODS: We conducted a study of patients who underwent laparoscopic-assisted gastrectomy in two large centers between June 2014 and April 2017. Patients' demographic and clinical characteristics and postoperative short-term outcomes were prospectively analyzed. Patients were divided into two groups depend on the preoperative presence of nutritional risk. Clinical variables were compared. Univariate analyses and multivariate logistic regression analyses evaluating the risk factors for postoperative complications were performed. RESULTS: A total of 256 patients, comprising 187 males and 69 females, met the inclusion criteria and were included in this study. The mean age was 61.81 years, the average BMI was 22.44 kg/m, and the average preoperative serum albumin was 39.42 g/l. Older age (P=0.001), higher tumor stage (P=0.047), lower BMI (P<0.001), lower preoperative serum albumin (P=0.005), and lower hemoglobin (P=0.013) were more common in the nutritional risk group. There were no significant differences in the short-term postoperative outcomes between nutritional risk and non-nutritional risk groups. Advanced age (P=0.024) and hypoalbuminemia (P=0.004) were independent risk factors for postoperative complications after laparoscopic-assisted gastrectomy. CONCLUSION: Nutritional risk may not be a clinical predictor of short-term outcomes after laparoscopic-assisted gastrectomy. Advanced age and preoperative hypoalbuminemia were independent risk factors for grade II or more postoperative complications.

Comparison of three common nutritional screening tools with the new European Society for Clinical Nutrition and Metabolism (ESPEN) criteria for malnutrition among patients with geriatric gastrointestinal cancer: a prospective study in China.

OBJECTIVE: The aim of this study was to evaluate and compare three common nutritional screening tools with the new European Society for Clinical Nutrition and Metabolism (ESPEN) diagnostic criteria for malnutrition among elderly patients with gastrointestinal cancer. RESEARCH METHODSANDPROCEDURES: Nutritional screening tools, including the Nutritional Risk Screening 2002 (NRS 2002), the Malnutrition Universal Screening Tool (MUST) and the Short Form of Mini Nutritional Assessment (MNA-SF), were applied to 255 patients with gastrointestinal cancer. We compared the diagnostic values of these tools for malnutrition, using the new ESPEN diagnostic criteria for malnutrition as the 'gold standards'. RESULTS: According to the new ESPEN diagnostic criteria for malnutrition, 20% of the patients were diagnosed as malnourished. With the use of NRS 2002, 52.2% of the patients were found to be at high risk of malnutrition; with the use of MUST, 37.6% of the patients were found to be at moderate/high risk of malnutrition; and according to MNA-SF, 47.8% of the patients were found to be at nutritional risk. MUST was best correlated with the ESPEN diagnostic criteria (К=0.530, p<0.001) compared with NRS 2002 (К=0.312, p<0.001) and MNA-SF (К=0.380, p<0.001). The receiver operating characteristic curve of MUST had the highest area under the curve (AUC) compared with NRS 2002 and MNA-SF. CONCLUSIONS: Among the tools, MUST was found to perform the best in identifyingmalnourished elderly patients with gastrointestinal cancer distinguished by the new ESPEN diagnostic criteria for malnutrition. Nevertheless, further studies are needed to verify our findings. TRIAL REGISTRATION NUMBER: ChiCTR-RRC-16009831; Pre-results.