Acute sleep deprivation (ASD) is often observed in shift workers and characterized by drowsiness and unrelenting exhaustion. The physiological and psychological effects of ASD include anxiety, depression, cognitive impairment, systemic inflammation, stress responses, and disruptions of gut microbiota. However, the mechanisms involved in the ASD-associated circadian dysregulations with regard to gut dysbiosis, systemic inflammation, physiological modulation, and psychiatry disorders remain unclear. The aim of this study was to investigate whether central nervous system disorders induced by ASD are related to inflammation, barrier dysfunction, and circadian dysregulation. We also assessed impacts on microbiota succession. Male C57BL/6 mice were randomly allocated to the control and sleep deprivation (SD) groups. Mice in the SD group were subjected to 72 h of paradoxical SD using the modified multiple-platform method for ASD induction (72 h rapid eye movement-SD). The effects of ASD on dietary consumption, behaviors, cytokines, microbiota, and functional genes were determined. The appetite of the SD group was significantly higher than that of the control group, but the body weight was significantly lower than that of the control group. The anxiety-like behaviors were found in the SD group. Alpha and beta diversity of microbiota showed significant decrease after ASD induction; the relative abundance of Candidatus_Arthromitus and Enterobacter was increased, whereas that abundance of Lactobacillus, Muribaculum, Monoglobus, Parasutterella, and others was decreased in the SD group. These effects were accompanied by reduction in fecal propionic acid. In the proximal colon, the SD group exhibited significantly higher inflammation (tumor necrosis factor-α [TNF-α]) and dysregulation of the circadian rhythms (brain and muscle ARNT-like 1 [BMAL1] and cryptochrome circadian regulator 1 [CRY1]) and tight junction genes (occludin [OCLN]) than the control group. Gut barrier dysfunction slightly increased the plasma concentration of lipopolysaccharide and significantly elevated TNF-α. Inflammatory signals might be transduced through the brain via TNF receptor superfamily member 1 A (TNFRSF1A), which significantly increased the levels of microglia activation marker (ionized calcium-binding adapter molecule 1 [IBA1]) and chemokine (intercellular adhesion molecule 1 [ICAM1]) in the cerebral cortex. The serotonin receptor (5-hydroxytryptamine 1A receptor [5-HT_1AR]) was significantly downregulated in the hippocampus. In summary, 72 h of rapid eye movement-SD induced physiological and psychological stress, which led to disruption of the circadian rhythms and gut microbiota dysbiosis; these effects were related to decrement of short chain fatty acids, gut inflammation, and hyperpermeability. The microbiota may be utilized as preventive and therapeutic strategies for ASD from the perspectives of medicine and nutrition.

The present study evaluated the potential beneficial effect of kefir (KF) against fatigue. Furthermore, the composition of the gut microbiota is related to health benefits in the host; therefore, the study also investigated the effect of KF on the gut microbiota composition. Male ICR mice from four groups (n = 8 per group) were orally administered KF once daily for four weeks at 0, 2.15, 4.31, and 10.76 g/kg/day and were designated as the vehicle, KF-1X, KF-2X, and KF-5X groups, respectively. The gut microbiota was analyzed using 16S rRNA gene sequencing. The results showed a significant clustering of cecum after treatment in the vehicle, KF-1X, KF-2X, and KF-5X groups. The KF-2X and KF-5X groups showed a decreased Firmicutes/Bacteroidetes ratio compared with the vehicle group. In addition, anti-fatigue activity and exercise performance were evaluated on the basis of exhaustive swimming time, forelimb grip strength, and levels of serum lactate, ammonia, glucose, blood urea nitrogen (BUN), and creatine kinase (CK) after a swimming exercise. The exhaustive swimming time for the KF-1X, KF-2X, and KF-5X groups was significantly longer than that for the vehicle group, and the forelimb grip strength of the KF-1X, KF-2X, and KF-5X groups was also significantly higher than that of the vehicle group. KF supplementation also decreased serum lactate, ammonia, BUN, and CK levels after the swimming test. However, tissue glycogen content, an important energy source for exercise, increased significantly with KF supplementation. Thus, KF supplementation can alter the gut microbiota composition, improve performance, and combat physical fatigue.

Context: Cinnamomum osmophloeum Kaneh. (Lauraceae) is one of the indigenous tree species in Taiwan. This tree species has been of interest to researchers because the chemical constituents of its essential oil are similar to those of Cinnamomum cassia Presl. bark oil, known as cinnamon oil, which is commonly used in foods and beverages. Objective: The anti-inflammatory activities of the leaf essential oils and their major compounds from seven provenances of C. osmophloeum are investigated here for the first time. Materials and methods: Chemical compositions of hydrodistilled essential oils obtained from C. osmophloeum leaves were analyzed by gas chromatography-mass spectrometry (GC-MS), and the effects of essential oils on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages were investigated. Results: The leaf essential oils of cinnamaldehyde type and mixed type strongly inhibited NO production, with IC₅₀ values ranging from 9.7-15.5 μg/mL. Furthermore, trans-cinnamaldehyde is responsible for the inhibitory activity of cinnamaldehyde type, and T-cadinol and α-cadinol are responsible for the inhibitory activity of mixed type. Discussion and conclusion: These findings demonstrate that the leaf essential oils and their constituents of C. osmophloeum have excellent anti-inflammatory activities and thus have great potential as a source for natural health products.