Melatonin alleviates oxidative stress in sleep deprived mice: Involvement of small intestinal mucosa injury

Lacticaseibacillus rhamnosus GG alleviates sleep deprivation-induced intestinal barrier dysfunction and neuroinflammation in mice

Consuming probiotic products is a solution that people are willing to choose to augment health. As a global health hazard, sleep deprivation (SD) can cause both physical and mental diseases. The present study investigated the protective effects of Lacticaseibacillus rhamnosus GG (LGG), a widely used probiotic, on a SD mouse model. Here, it has been shown that SD induced intestinal damage in mice, while LGG supplementation attenuated disruption of the intestinal barrier and enhanced the antioxidant capacity. Microbiome analysis revealed that SD caused dysbiosis in the gut microbiota, characterized by increased levels of Clostridium XlVa, Alistipes, and Desulfovibrio, as well as decreased levels of Ruminococcus, which were partially ameliorated by LGG. Moreover, SD resulted in elevated pro-inflammatory cytokine concentrations in both the intestine and the brain, while LGG provided protection in both organs. LGG supplementation significantly improved locomotor activity in SD mice. Although heat-killed LGG showed some protective effects in SD mice, its overall efficacy was inferior to that of live LGG. In terms of mechanism, it was found that AG1478, an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, could diminish the protective effects of LGG. In conclusion, LGG demonstrated the ability to alleviate SD-induced intestinal barrier dysfunction through EGFR activation and alleviate neuroinflammation.

A systematic review of preclinical studies targeted toward the management of co-existing functional gastrointestinal disorders, stress, and gut dysbiosis

Modern dietary habits and stressed lifestyle have escalated the tendency to develop functional gastrointestinal disorders (FGIDs) through alteration in the gut-brain-microbiome axis. Clinical practices use symptomatic treatments, neglect root causes, and prolong distress in patients. The past decade has seen the evolution of various interventions to attenuate FGIDs. But clinical translation of such studies is very rare mostly due to lack of awareness. The aim of this review is to meticulously integrate different studies and bridge this knowledge gap. Literature between 2013 and 2023 was retrieved from PubMed, ProQuest, and Web of Science. The data was extracted based on the PRISMA guidelines and using the SYRCLE's risk of bias and the Cochrane Risk of Bias tools, quality assessment was performed. The review has highlighted molecular insights into the coexistence of FGIDs, stress, and gut dysbiosis. Furthermore, novel interventions focusing on diet, probiotics, herbal formulations, and phytoconstituents were explored which mostly had a multitargeted approach for the management of the diseases. Scientific literature implied positive interactions between the interventions and the gut microbiome by increasing the relative abundance of beneficial bacteria and reducing stress-related hormones. Moreover, the interventions reduced intestinal inflammation and regulated the expression of epithelial tight junction proteins in different in vivo models. This systematic review delves deep into the preclinical interventions to manage coexisting FGIDs, stress, and gut dysbiosis. However, in most of the discussed studies, long-term risks and toxicity profile of the interventions are lacking. So, it is necessary to highlight them for improved clinical outcomes.

Sleep deprivation during pregnancy leads to poor fetal outcomes in Sprague-Dawley rats

Sleep deprivation is a common problem during pregnancy, but its impact on the fetus remains unclear. We aimed to investigate the effect of sleep deprivation during pregnancy on fetal outcomes and its mechanism in Sprague-Dawley rats. Sleep deprivation was performed from gestational day(GD) 1-19 using a multiplatform method for 18 h/day. Rats were sacrificed on GD20, and their blood and placentas were collected. Fetal and placental parameters were ascertained. Melatonin, adrenocorticotropic hormone (ACTH) and corticosterone were also measured in serum. The levels of arylalkylamine N-acetyltransferase (AANAT) and two melatonin receptors MT1 and MT2, in placental tissues were detected by western blotting. The inflammatory status and oxidative stress in serum and placentas were investigated. Miscarriage and intrauterine growth restriction were observed in the sleep deprivation group. Sleep deprivation resulted in an increased fetal absorption rate, while fetal weight, crown-rump length and placental weight were reduced. Placental histopathology showed that the labyrinth ratio in the sleep deprivation group was significantly reduced, with hypoplastic villi and obviously decreased blood vessels. Sleep deprivation decreased melatonin in serum and the expression of AANAT, MT1 and MT2 in placental tissues, elevated the oxidative stress products 8-hydroxy-deoxyguanosine (8-OHdG) and malondialdehyde(MDA) in serum and 4-hydroxynonenal (4HNE) in the placenta, and decreased the antioxidants superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in serum. Serum proinflammatory cytokines including interleukin-1-beta (IL-1β), interleukin-6 (IL-6), necrotizing factor-alpha (TNF-α), and interleukin-8(IL-8), were all elevated by sleep deprivation, and the inflammatory regulatory factor nuclear factor-κB p65 (NF-κB p65) in the placenta was enhanced when examined by immunohistochemistry. Corticosterone levels were comparable between the two groups, although ACTH levels were elevated significantly in the sleep deprivation group. Our study revealed that sleep deprivation during pregnancy can adversely impact fetal outcomes. Melatonin may play an important role in this pathology through the oxido-inflammatory process.

Targeting microbiota to alleviate the harm caused by sleep deprivation

Sleep deprivation has become a common health hazard, affecting 37-58% of the population and promoting the occurrence and development of many diseases. To date, effective treatment strategies are still elusive. Accumulating evidence indicates that modulating the intestinal microbiota harbors significant potential for alleviating the deleterious impacts of sleep deprivation. This paper first reviews the effects of sleep deprivation on gastrointestinal diseases, metabolic diseases, and neuropsychiatric diseases, discussing its specific mechanisms of influence. We then focus on summarizing existing interventions, including probiotics, melatonin, prebiotics, diet, and fecal microbiota transplantation (FMT). Finally, we have discussed the advantages and limitations of each strategy. Compared with other strategies, probiotics showed a high potential in alleviating sleep deprivation-related hazards due to their reduced risk and high security. We suggest that future research should focus on the specific mechanisms by which probiotics mitigate the harms of sleep deprivation, such insights may unveil novel pathways for treating diseases exacerbated by insufficient sleep.

Butyrate Ameliorates Insufficient Sleep-Induced Intestinal Mucosal Damage in Humans and Mice

Insufficient sleep is a key factor in the occurrence of intestinal diseases. This study was performed to clarify how sleep deficiency mediates the intestinal microbiota, metabolite butyrate disturbance induces intestinal mucosal damage, and butyrate ameliorates it. A questionnaire was launched for sleep and intestinal health issues. Twenty-two healthy volunteers were interviewed, and the influence of insufficient sleep on the gut microbiota and metabolite composition was explored. Moreover, a 72-h sleep deprivation (SD) mouse model with or without butyrate supplementation was used to reveal the effect of butyrate on ameliorating small intestines damage caused by SD. The questionnaire survey of 534 college students showed that among 85.39% of the students who slept less than 7 h, 41.76% were suffering from various bowel disorders. High-throughput 16S rRNA pyrosequencing demonstrated that SD and sleep restriction (SR) resulted in downregulation of Faecalibacterium and butyrate abundance in the feces of college students. Furthermore, we observed that butyrate supplementation markedly reversed sleep-deprivation-induced small intestinal mucosal injury in mice. Meanwhile, butyrate supplementation inverted the SD-caused inflammation response and oxidative stress and the decline of phospho-glycogen synthase kinase 3β (p-GSK-3β), β-catenin, Nrf2, and cyclin D1 and the increase in histone deacetylase 3 (HDAC3) and phospho-P65 (p-P65) proteins in the small intestines. Furthermore, in vitro, the ameliorative effects of butyrate were blocked by treatment with the HDAC3 agonist ITSA-1 and the Nrf2 antagonist ML385 and mimicked by treatment with the HDAC3 antagonist RGFP966 and p-P65 antagonist PDTC. Our study revealed that SD and SR downregulated butyrate production, further causing intestinal homeostasis dysfunction via the HDAC3-p-GSK-3β-β-catenin-Nrf2-NF-κB pathway. IMPORTANCE Radical inflammatory bowel disease (IBD) induced by sleep deficiency is a serious global public health threat. Butyrate, a member of the short-chain fatty acids, exerts multiple effects on it. However, existing research focuses on injury to the colon caused by insufficient sleep, while the changes in the small intestines are often overlooked. This study focused on revealing the influence of insufficient sleep on the intestinal microbiota and its metabolites and further revealed the ameliorative effect of butyrate on sleep deprivation (SD)-induced small intestinal mucosal damage in human and mice. Our studies suggest that butyrate can be used as a probiotic to restore SD-induced IBD and contribute to a better understanding of the mechanisms that govern the beneficial effects of butyrate.

Melatonin and inflammatory bowel disease: From basic mechanisms to clinical application

Inflammatory bowel disease is a chronic inflammatory disease and has periods of recurrence and remission. Improper immune responses to gut flora bacteria, along with genetic susceptibility, appear to be involved in causing this complex disease. It seems dysbiosis and oxidative stress may also be involved in IBD pathogenesis. A significant number of clinical studies have shown an interesting association between sleep disturbances and IBD. Studies in animal models have also shown that sleep deprivation has a significant effect on the pathogenesis of IBD and can aggravate inflammation. These interesting findings have drawn attention to melatonin, a sleep-related hormone. Melatonin is mainly produced by the pineal gland, but many tissues in the body, including the intestines, can produce it. Melatonin can have an interesting effect on the pathogenesis of IBD. Melatonin can enhance the intestinal mucosal barrier, alter the composition of intestinal bacteria in favor of bacteria with anti-inflammatory properties, regulate the immune response, alleviate inflammation and attenuate oxidative stress. It seems that, melatonin supplementation is effective in relieving inflammation and healing intestinal ulcers in IBD animal models. Some clinical studies have also shown that melatonin supplementation as an adjuvant therapy may be helpful in reducing disease activity in IBD patients. In this review article, in addition to reviewing the effects of sleep disturbances and melatonin on key mechanisms involved in the pathogenesis of IBD, we will review the findings of clinical studies regarding the effects of melatonin supplementation on IBD treatment.

Akkermansia muciniphila Colonization Alleviating High Fructose and Restraint Stress-Induced Jejunal Mucosal Barrier Disruption

Akkermansia muciniphila (A. muciniphila) is a mucin-degrading bacterium that resides in the mucus layer, but its potential in intestinal inflammatory diseases has sparked controversy. It is well known that both the consumption of fructose-containing beverages and psychological stress increase the risk of intestinal disease. Our results revealed that a high-fructose diet aggravated the damage to the jejunal mucosal barrier caused by restraint stress, reduced tight junction protein expression and the intestinal digestion and absorption capacity, disrupted the ability of Paneth cells to secrete antimicrobial peptides, and promoted the expression of inflammatory cytokines. A. muciniphila colonization enhanced the defense function of the mucosal barrier by enhancing the function of the NLRP6, promoting autophagy, maintaining the normal secretion of antimicrobial peptides in Paneth cells, promoting the expression of tight junction proteins, negatively regulating the NF-kB signaling pathway and inhibiting the expression of inflammatory cytokines. Our work indicates that A. muciniphila ameliorates the disruption of the intestinal mucosal barrier under high fructose and restraint stress. These results provided a rationale for the development of probiotic colonization for the prevention or treatment of intestinal diseases.

Melatonin prevents the dysbiosis of intestinal microbiota in sleep-restricted mice by improving oxidative stress and inhibiting inflammation

BACKGROUND

Intestinal inflammation caused by sleep restriction (SR) threatens human health. However, radical cure of intestinal inflammatory conditions is considerably difficult. This study focuses on the effect of melatonin on SR-induced intestinal inflammation and microbiota imbalance in mice.

METHODS

We successfully established a water platform to induce long-term SR in mice for 28 days with or without melatonin supplementation. The SR-induced oxidative stress and inflammatory changes were evaluated in plasma and jejunum tissue samples using in vitro assays. Additionally, changes in the intestinal microbiota were explored using high-throughput sequencing of the 16S rRNA gene.

RESULTS

After 20 h of chronic sleep restriction for 28 consecutive days, plasma melatonin was significantly reduced by 48.91% (P < 0.05), while GLU, NE, and CORT were significantly increased (34.32%-90.28%, P < 0.05). The activities of antioxidant enzymes (SOD, GSH-Px, and CAT) and T-AOC in intestinal tissues of SR mice were decreased (17.02%-40.92%, P < 0.05), while the content of MDA was increased (15.12%, P = 0.0089). The levels of pro-inflammatory cytokines (IL-6 and TNF-α) ware increased (65.27%-123.26%, P < 0.05), while the levels of anti-inflammatory cytokines (IL-10 and IFN-γ) were decreased (26.53%-60.41%, P < 0.05). High-throughput pyrosequencing of 16S rRNA from jejunum samples demonstrated an overall increase in the number of OTUs (30.68%, P = 0.015). The α-diversity (Shannon, ACE and Chao1) of jejunum was increased (28.18%-48.95%, P < 0.05), and the β-diversity (PCoA and NMDS) was significantly different from that of the control group (P = 0.001). Furthermore, the prevalences of Helicobacter and Clostridium were higher, whereas that of Bacteroidetes and Lactobacillus were lower in SR mice than in controls (P < 0.05). However, melatonin supplementation reversed the SR-induced changes and improved oxidative stress, inflammatory response, and microbiota dysbiosis in the jejunum, and there was not significant difference compared with the control group (P > 0.05).

CONCLUSIONS

Melatonin prevents the dysbiosis of intestinal microbiota in SR mice by improving oxidative stress and inhibiting inflammation. Our results may provide a theoretical basis for conducting clinical research on insufficient sleep leading to intestinal health in humans and hence facilitate a better understanding of the role of melatonin.

Insulin resistance induced by long-term sleep deprivation in rhesus macaques can be attenuated by Bifidobacterium

Long-term sleep deprivation (SD) is a bad lifestyle habit, especially among specific occupational practitioners, characterized by circadian rhythm misalignment and abnormal sleep/wake cycles. SD is closely associated with an increased risk of metabolic disturbance, particularly obesity and insulin resistance. The incretin hormone, glucagon-like peptide-1 (GLP-1), is a critical insulin release determinant secreted by the intestinal L-cell upon food intake. Besides, the gut microbiota participates in metabolic homeostasis and regulates GLP-1 release in a circadian rhythm manner. As a commonly recognized intestinal probiotic, Bifidobacterium has various clinical indications regarding its curative effect. However, few studies have investigated the effect of Bifidobacterium supplementation on sleep disorders. In the present study, we explored the impact of long-term SD on the endocrine metabolism of rhesus monkeys and determined the effect of Bifidobacterium supplementation on the SD-induced metabolic status. Lipid concentrations, body weight, fast blood glucose, and insulin levels increased after SD. Furthermore, after 2 mo of long-term SD, the intravenous glucose tolerance test showed that the glucose metabolism was impaired and the insulin sensitivity decreased. Moreover, 1 mo of Bifidobacterium oral administration significantly reduced blood glucose and attenuated insulin resistance in rhesus macaques. Overall, our results suggested that Bifidobacterium might be used to alleviate SD-induced aberrant glucose metabolism and improve insulin resistance. Also, it might help in better understanding the mechanisms governing the beneficial effects of Bifidobacterium.NEW & NOTEWORTHY Our findings demonstrated that long-term sleep deprivation is closely associated with metabolic syndromes. Bifidobacterium administration showed a superior effect on insulin resistance caused by sleep deprivation. Overall, we provide prevention and treatment methods for long-term sleep deprivation, a bad lifestyle habit among specific occupational practitioners, such as irregular shift workers.

Melatonin-Mediated Colonic Microbiota Metabolite Butyrate Prevents Acute Sleep Deprivation-Induced Colitis in Mice

Radical cure colitis is a severe public health threat worldwide. Our previous studies have confirmed that melatonin can effectively improve gut microbiota disorder and mucosal injury caused by sleep deprivation (SD). The present study further explored the mechanism whereby exogenous melatonin prevented SD-induced colitis. 16S rRNA high-throughput sequencing and metabolomics analysis were used to explore the correlation between SD-induced colitis and intestinal microbiota and metabolite composition in mice. Fecal microbiota transplantation (FMT) and melatonin or butyrate supplementation tests verified the core role of gut microbiota in melatonin-alleviating SD-induced colitis. Further, in vitro tests studied the modulatory mechanism of metabolite butyrate. The results demonstrated that SD leads to reductions in plasma melatonin levels and colonic Card9 expression and consequent occurrence of colitis and gut microbiota disorder, especially the downregulation of Faecalibacterium and butyrate levels. The FMT from SD-mice to normal mice could restore SD-like colitis, while butyrate supplementation to SD-mice inhibited the occurrence of colitis, but with no change in the plasma melatonin level in both treatments. However, melatonin supplementation reversed all inductions in SD-mice. In intestinal epithelial cells, the inflammatory ameliorative effect of butyrate was blocked with pretreatments of HDAC3 agonist and HIF-1α antagonist but was mimicked by GSK-3β and p-P65 antagonists. Therefore, the administration of MLT may be a better therapy for SD-induced colitis relative to butyrate. A feasible mechanism would involve that melatonin up-regulated the Faecalibacterium population and production of its metabolite butyrate and MCT1 expression and inhibited HDAC3 in the colon, which would allow p-GSK-3β/β-catenin/HIF-1α activation and NF-κB/NLRP3 suppression to up-regulate Card9 expression and suppress inflammation response.

Application of armodafinil-loaded microneedle patches against the negative influence induced by sleep deprivation

Cognition maintenance is essential for healthy and safe life if sleep deprivation happens. Armodafinil is a wake-promoting agent against sleep deprivation related disorders. However, only the tablet formulation is available, which may limit its potential in some circumstances. Here, we report the synthesis of a new formulation of armodafinil, microneedle patches, which can be conveniently used by any individual and removed in time if not wanted. To produce the needles of higher mechanical strength and higher drug loading, polyvinylpyrrolidone (PVP) K90 was used to fabricate armodafinil-loaded microneedles by applying the mold casting method after dissolving in methanol and drying. The higher mechanical strength was validated by COMSOL Multiphysics® software stimulation and universal mechanical testing machines. The obtained armodafinil microneedles can withstand a force of 70 N and penetrate the skin to a depth of 230 μm, and quickly released the drug within 1.5 h in vitro. The pharmacokinetic analysis showed that microneedle administration can maintain a more lasting and stable blood concentration as compared to oral administration. After the treatment of sleep deprived mice with microneedles, the in vivo pharmacodynamics study clearly demonstrated that armodafinil microneedles could eliminate the effects of sleep deprivation and improve the cognitive functions of sleep-deprived mice. A self-administered, high drug-loaded microneedle patch were prepared successfully, which appeared to be highly promising in preserving cognition by transdermal administration.