MicroRNA-23a Curbs Necrosis during Early T Cell Activation by Enforcing Intracellular Reactive Oxygen Species Equilibrium.

Upon antigen engagement, augmented cytosolic reactive oxygen species (ROS) are needed to achieve optimal T cell receptor (TCR) signaling. However, uncontrolled ROS production is a prominent cause of necrosis, which elicits hyper-inflammation and tissue damage. Hence, it is critical to program activated T cells to achieve ROS equilibrium. Here, we determined that miR-23a is indispensable for effector CD4(+) T cell expansion, particularly by providing early protection from excessive necrosis. Mechanistically, miR-23a targeted PPIF, gatekeeper of the mitochondria permeability transition pore, thereby restricting ROS flux and maintaining mitochondrial integrity. Upon acute Listeria monocytogenes infection, deleting miR-23a in T cells resulted in excessive inflammation, massive liver damage, and a marked mortality increase, which highlights the essential role of miR-23a in maintaining immune homeostasis.

l-Theanine delays d-galactose-induced senescence by regulating the cell cycle and inhibiting apoptosis in rat intestinal cells.

BACKGROUND: Intestinal senescence is associated with several aging-related diseases. l-Theanine (LTA) has demonstrated strong potential as an antioxidant and antisenescence agent. This study investigated the regulatory effect of LTA on cellular senescence using an in vitro model of d-galactose (D-Gal)-induced senescence in the rat epithelial cell line, intestinal epithelioid cell-6 (IEC-6). RESULTS: Treatment of IEC-6 cells with 40 mg/mL D-Gal for 48 h resulted in the successful development of the senescent cell model. Compared with D-Gal alone, both LTA preventive and delayed intervention increased cell viability and the ratio of JC-1 monomers to aggregates, increased the antioxidant capacity, and decreased the advanced glycation end product (AGE) levels and the overall number of senescent cells. Preventive and delayed intervention with 1000 µM LTA alleviated the D-Gal-induced cell cycle arrest by regulating p38, p53, CDK4, and CDK6 expression at the mRNA and protein levels, and further induced CycD1 proteins. Moreover, LTA preventive intervention reduced apoptosis to a greater degree than delayed intervention by upregulating the expression of the receptors of AGEs, Bax, Bcl-2, and NF-κB at the mRNA and protein levels. CONCLUSION: Our findings indicate that LTA intervention could attenuate senescence in IEC-6 cells by regulating the cell cycle and inhibiting apoptosis. © 2023 Society of Chemical Industry.

L-Theanine alleviates heat stress through modulation of gut microbiota and immunity.

BACKGROUND: Heat stress (HS) damages the intestines, disrupting gut microbiota and immune balance. l-Theanine (LTA), found in tea, alleviates oxidative stress and cell apoptosis under HS; however, its effects on gut microbiota and immunity under HS remain unclear. To investigate this, we administered LTA doses of 100, 200, and 400 mg·kg-1 ·d-1 to C57BL/6J mice. On day 44, the model group and LTA intervention group were subjected to continuous 7-day HS treatment for 2 h per day. RESULTS: The results demonstrated that LTA intervention improved food intake, body weight, and intestinal epithelium, and reduced the water intake of heat-stressed mice. It increased the abundance of Turicibacter, Faecalibaculum, Bifidobacterium, and norank_f_Muribaculaceae, while reducing that of Lachnoclostridium and Desulfovibrio. LTA intervention also increased the concentrations of amino acid and lipid metabolites, regulated macrophage differentiation stimulated by gut microbiota and metabolites, reduced the antigen presentation by macrophages to the specific immune system, promoted B-cell differentiation and sIgA secretion, inhibited pro-inflammatory factors, and enhanced intestinal defense. Mechanistically, LTA downregulated heat shock protein 70 expression and the TLR4/NF-κB/p38 MAPK signaling pathway, restoring gut microbiota and immune balance. CONCLUSION: We suggest that LTA can alleviate HS by modulating gut microbiota, metabolites, and immunity, indicating its potential as a natural active ingredient for anti-HS food products. © 2023 Society of Chemical Industry.

L-Theanine regulates lipid metabolism by modulating gut microbiota and bile acid metabolism.

BACKGROUND: l-Theanine (LTA) is a biologically active ingredient in tea that shows great potential for regulating lipid metabolism. Bile acids (BA), an important end-product of cholesterol catabolism, participate in the regulation of lipid metabolism and gut microbiota. Here, we investigated the effect of LTA on lipid metabolism and the mechanism by which it regulates BA metabolism and gut microbiota. Male BALB/c mice were treated with LTA for 28 days. RESULTS: Daily LTA doses of 100 and 300 mg kg-1  d-1 altered the gut microbiota in mice, predominantly by decreasing Lactobacillus, Streptococcus, Bacteroides, Clostridium and Enterorhabdus microbes associated with bile-salt hydrolase (BSH) activity, thereby decreasing the activity of BSH and increasing the levels of ileum conjugated BA (such as glycocholic acid (GCA) and lithocholic acid), thereby inhibiting the intestinal farnesoid X receptor (FXR)-fibroblast growth factor 15 (FGF15) signaling pathway. Inhibition of FXR-FGF15 signaling was accompanied by upregulation of cholesterol 7α-hydroxylase (CYP7A1) mRNA and protein expression and increased hepatic production of cholic acid, deoxycholic acid, GCA, glycine cholic acid and glycine ursodeoxycholic acid. Meanwhile, increasing hepatic unconjugated BA upregulated the mRNA and protein expression of liver 3-hydroxy-3-methylglutaryl-CoA reductase and downregulated the mRNA and protein expression of stearoyl-CoA desaturase-1, liver low-density lipoprotein receptor and type B scavenger receptor. Therefore, the serum levels of cholesterol and triglycerides decreased. CONCLUSION: Our findings indicate that LTA regulates lipid metabolism by modulating the gut microbiota and BA metabolism via the FXR-FGF15-CYP7A1 pathway. © 2022 Society of Chemical Industry.

Metagenomics Approach to the Intestinal Microbiome Structure and Abundance in High-Fat-Diet-Induced Hyperlipidemic Rat Fed with (-)-Epigallocatechin-3-Gallate Nanoparticles.

The effects of nanoparticles (NPs) on microbiota homeostasis and their physiological relevance are still unclear. Herein, we compared the modulation and consequent pharmacological effects of oral administration of (-)-epigallocatechin-3-gallate (EGCG)-loaded ß-cyclodextrin (ß-CD) NPs (EGCG@ß-CD NPs) and EGCG on gut microbiota. EGCG@ß-CD NPs were prepared using self-assembly and their influence on the intestinal microbiome structure was analyzed using a metagenomics approach. The "Encapsulation efficiency (EE), particle size, polydispersity index (PDI), zeta potential" of EGCG@ß-CD NPs were recorded as 98.27 ± 0.36%, 124.6 nm, 0.313 and -24.3 mV, respectively. Surface morphology of EGCG@ß-CD NPs was observed as spherical. Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and molecular docking studies confirmed that EGCG could be well encapsulated in ß-CD and formed as EGCG@ß-CD NPs. After being continuously administered EGCG@ß-CD NPs for 8 weeks, the serum cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and liver malondialdehyde (MDA) levels in the rats were significantly decreased, while the levels of catalase (CAT) and apolipoprotein-A1 (apo-A1) in the liver increased significantly in the hyperlipidemia model of rats, when compared to the high-fat-diet group. Furthermore, metagenomic analysis revealed that the ratio of Verrucomicrobia/Bacteroidetes was altered and Bacteroidetes decreased in the high-fat diet +200 mg/kg·bw EGCG@ß-CD NPs group, while the abundance of Verrucomicrobia was significantly increased, especially Akkermansia muciniphila in rat feces. EGCG@ß-CD NPs could be a promising EGCG delivery strategy to modulate the gut microbiota, enhancing its employment in the prevention of hyperlipidemia.

[Effect of Biyanning Granules on local symptoms and immune function of chronic rhinosinusitis].

This study discusses the effect of Biyanning Granules on local symptoms and systemic immune function of patients with chronic rhinosinusitis with nasal polyps(CRSwNP) within the 6 months of treatment by glucocorticoid nasal spray after surgical treatment. To be specific, a total of 237 CRSwNP patients, treated in Otorhinolaryngology Head and Neck Surgery in Shanxi Bethune Hospital, were enrolled. All patients were treated by nasal endoscopy and classified into hormone group(Budesonide Nasal Spray after surgery), Chinese medicine group(Biyanning Granules after surgery), and combination group(Budesonide Nasal Spray+Biyanning Granules after surgery) with random number table method, 79 cases in each group, and the treatment lasted 3 months. The follow-up was performed from the day of discharge to 12 months after the surgery. The clinical effect was observed. The visual analogue scale(VAS) scores and sino-nasal outcome test-20(SNOT-20) scale scores were used to assess patient's subjective symptoms and quality of life. Lund-Kennedy endoscopic score(LKES), Japanese T&T olfactometry, and standard olfactory test were used to evaluate the objective curative effect on patients. The levels of interleukin(IL)-21, CD4~+CD25~+Foxp3~+Treg, and CD4~+Th17 in peripheral blood were analyzed. The incidence of complications, recurrence rate, and adverse reactions during treatment were also recorded. The total effective rate after treatment in the combination group was higher than that in the hormone group and Chinese medicine group(P<0.05). VAS scores and SNOT-20 scale scores were lower in the three groups after treatment than before treatment and lower in the combination group than in the other two groups(P<0.05). The improvement in LKES and T&T standard olfactometry test was better in the combination group than in the other two groups(P<0.05). Serum levels of IL-21 and CD4~+Th17 in the three groups were lower than before treatment. The levels in the combination group were lower than those in the other two groups and lower in the hormone group than in the Chinese medicine group(P<0.05). Serum CD4~+CD25~+Foxp3~+Treg level was higher in the three groups after treatment than before, higher in the combination group than in the other two groups, and higher in the Chinese medicine group than in the hormone group(P<0.05). During the treatment, no serious adverse reactions were observed. After treatment, the combination group showed no significant difference in the incidence and recurrence rate of complications from the hormone group and Chinese medicine group. In the treatment of CRSwNP with glucocorticoid, Biyanning Granules reduced the side effects of glucocorticoid and assisted glucocorticoid in alleviating the symptoms of patients. It significantly improved the curative effect, regulated immune imbalance, accele-rated the recovery of immune function, reduced the recurrence rate of inflammatory reaction, and improved the quality of life. The combination of Chinese and western treatment is more effective than glucocorticoid alone and warrants further clinical study in large sample size.

A pooled analysis of primary hepatic angiosarcoma.

BACKGROUND: Angiosarcoma is an aggressive and malignant neoplasm. Primary hepatic angiosarcoma is extremely rare and accounts for only approximately 5% of all angiosarcomas. Therefore, many doctors do not know enough about this disease; this lack of knowledge motivated us to perform this study. METHODS: We carried out a systematic review of the literature published worldwide from 1990 to 2019 to study the main characteristics, demographics, treatment and prognosis of primary hepatic angiosarcoma. RESULT: A total of 219 patients were included in this study. Patients were mainly middle-aged and elderly at diagnosis, with an average age at onset of 56.7 years. The vast majority of patients (61.5%) presented with abdominal pain or distension. Of 143 patients with clear records of metastasis, 31.5% (45 patients) had distant metastasis. The median overall survival time was only 6 months, and the 1- and 2-year survival rates were 30.4 and 17.3%, respectively. Sex, age, tumor size and metastasis at diagnosis showed no correlation with survival rate. Hepatic rupture was a significant predictor of survival. Surgery is a major treatment choice, and adjuvant chemotherapy can improve the prognosis of patients. Hepatic artery embolization is mainly used in cases of tumor rupture. However, liver transplantation is not advised. CONCLUSION: We presented an overview of the demographics, tumor characteristics and treatment outcomes of the largest number of primary hepatic angiosarcoma patients investigated to date. We highlight the use of routine physical examinations and surgery combined with adjuvant chemotherapy to improve the outcomes in these cases.

Programmed death ligand 1 expression and CD8+ tumor-infiltrating lymphocyte density differences between paired primary and brain metastatic lesions in non-small cell lung cancer.

Immunotherapy targeting the programmed cell death-1/programmed death ligand 1(PD-L1) pathway has shown promising antitumor activity in brain metastases (BMs) of non-small cell lung cancer (NSCLC) patients with an acceptable safety profile; however, the response rates often differ between primary lesions and intracranial lesions. Studies are necessary to identify detailed characterizations of the response biomarkers. In this study, we aimed to compare the differences of PD-L1 expression and CD8+ tumor-infiltrating lymphocyte (TIL) density, two major response biomarkers of PD-1/PD-L1 blockade, between paired primary and brain metastatic lesions in advanced NSCLC. We observed that among primary lesions or BMs, only a small number of patients harbored common PD-L1 expression on both tumor cells and tumor-infiltrating immune cells. Additionally, we found that the numbers of CD8+ TILs were significantly fewer in BMs than in primary lung cancers. Low stromal CD8+ TIL numbers in BMs were associated with significantly shorter overall survival compared to high stromal CD8+ TIL counts. Notably, we demonstrated a discrepancy in PD-L1 expression and CD8+ TIL density between primary lung cancers and their corresponding BMs. Such heterogeneities are significantly associated with the time at which BMs occurred. Our study emphasizes the spatial and temporal heterogeneity of biomarkers for anti-PD-1/PD-L1 therapy, which should be concerned in clinical practice.

[Association between body mass index and cardiovascular events in male elderly hypertensive patients].

OBJECTIVE: To observe the long-term relationship between body mass index (BMI) and cardiovascular events in male elderly hypertensive patients. METHODS: A total of 839 male elderly (>65 years old) hypertensive patients were included in this prospective study. Baseline data were obtained on January 2004 and participants were followed up yearly till January 2014. Patients were divided into 3 groups according to their BMI: normal weight group (18.5 kg/m² ≤ BMI<24.0 kg/²), overweight group (24.0 kg/m² ≤ BMI<28.0 kg/m²), obese group (BMI ≥ 28.0 kg/m²). All-cause death and cardiovascular events were compared. RESULTS: The average age of all 839 hypertension men was (75.4 ± 4.8) years at baseline. Baseline systolic blood pressure was (133.7 ± 14.6) mmHg (1 mmHg=0.133 kPa), diastolic blood pressure was (74.3 ± 9.3)mmHg. Baseline systolic and diastolic blood pressure was similar among the three groups. All 839 patients completed follow-up. There were 178 all-cause deaths, 54 cardiovascular deaths, 51 new/recurrent myocardial infarctions and 105 new/recurrent strokes during follow up. Incidence of all-cause mortality in overweight group (16.74%,72/430) was significantly lower than in normal weight group (27.01% (74/274), P<0.05). Kaplan-Meier curves showed the all-cause mortality and cardiovascular mortality were higher in normal weight group than in the other two groups. According to the Cox proportional hazards regression model, the risk of all-cause mortality (RR=0.867, 95% CI: 0.792-0.949) and cardiovascular death (RR=0.179, 95% CI : 0.05-0.645) in patients with a BMI ≥ 24.0 kg/m² were lower than in the group with BMI<24.0 kg/m². CONCLUSION: Obesity paradox phenomenon is observed in elderly male hypertensive patients in that higher BMI is associated with lower mortality risks in elderly male hypertensive patients during the 10 years follow-up.

Polymorphism of stromal cell-derived factor-1 selectively upregulates gene expression and is associated with increased susceptibility to coronary artery disease.

Stromal cell-derived factor-1 (SDF-1) plays critical roles in vascular development and hematopoiesis. Here, we investigated the function of SDF-1 rs1801157G/A polymorphism in various immune cells and examined its association with susceptibility to coronary artery disease (CAD). Protein and mRNA levels of SDF-1 were tested in peripheral CD4+ T cell, CD8+ T cells, monocytes, and natural killer (NK) T cells from healthy donors with different genotypes of rs1801157G/A polymorphism. Prevalence of the polymorphism was compared between CAD patients and healthy controls. Data revealed that SDF-1 mRNA and protein were detectable in CD4+ T cells, CD8+ T cells, monocytes and NK T cells. Interestingly, both protein level and mRNA level of SDF-1 were significantly increased in the monocytes with rs1801157AA genotype, whereas the same phenomenon was not observed in the other three cell types. Blockage of CD14 completely inhibited the upregulation of SDF-1 in the monocytes with rs1801157AA genotype. Association analysis showed that frequencies of the rs1801157AA genotype and A allele were significantly higher in CAD cases than in controls (odds ratio [OR]=2.28, 95% confidence interval [CI], 1.50-3.29, p<0.0001, and OR=1.46, 95% CI, 1.21-3.73, p<0.0001, respectively). Also, prevalence of rs1801157AA genotype was further increased in cases with ST-elevation myocardial infarction (OR=1.65, 95% CI, 1.04-2.56, p=0.028). Our data suggest a novel pathway for regulating SDF-1 and a new risk factor for CAD.

Regulatory Effects and Mechanisms of L-Theanine on Neurotransmitters via Liver-Brain Axis Under a High Protein Diet.

Excessive protein intake causes liver and brain damage and neurotransmitter disorders, thereby inducing cognitive dysfunction. L-theanine can regulate the neurotransmitter content and show great potential in liver and brain protection. However, it remains unclear whether l-theanine effectively regulates neurotransmitter content under high-protein diet. A 40-day feeding experiment was performed in Sprague Dawley rats to investigate the regulatory effects and mechanisms of l-theanine on neurotransmitters via liver-brain axis in high-protein diets. The results showed that a 30% protein diet increased the liver and brain neurotransmitter content while maintaining the normal structure of liver and the hippocampal CA1 of brain and improving the autonomous behavior of rats. In contrast, 40% and 50% protein diets decreased the content of neurotransmitters, affected autonomous behavior, destroyed the hippocampal CA1 of brain structure, increased hepatic inflammatory infiltration, lipid degeneration, and hepatocyte eosinophilic change in liver, increased liver AST, ALT, MDA, CRP, and blood ammonia level, and decreased liver SOD and CAT level. However, l-theanine improved liver and brain neurotransmitter content, autonomous behavior, liver and hippocampal brain structure, and liver biochemical indicators in 40% and 50% protein diets. To explore how LTA can eliminate the adverse effects of a high-protein diet, we analyzed different metabolites and proteomes and using western blotting for validate quantitatively. We found that l-theanine regulates the activity of PF4 and G protein subunit alpha i2, increases the content of brain-derived neurotrophic factor and dopamine under a 20% protein diet. In addition, l-theanine can activate the adenylate cyclase-protein kinase A pathway through the protein alpha/beta-hydrolase domain protein 12 to regulate the content of neurotransmitters under a 40% protein diet, thereby exerting a neuroprotective effect.

The protective effect of L-theanine on the intestinal barrier in heat-stressed organisms.

Heat stress caused by heatwaves, extreme temperatures, and other weather can damage the intestinal barrier of organisms. L-Theanine (LTA) attenuates heat stress-induced oxidative stress, inflammatory responses, and impaired immune function, but its protective effect on the intestinal barrier of heat-stressed organisms is unclear. In this study, low (100 mg kg-1 d-1), medium (200 mg kg-1 d-1), and high (400 mg kg-1 d-1) dosages of LTA were used in the gavage of C57BL/6J male mice that were experimented on for 50 d. These mice were subjected to heat stress for 2 h d-1 at 40 ± 1 °C and 60 ± 5% RH in the last 7 d. LTA attenuated the heat stress-induced decreases in body mass and feed intake, and the destruction of intestinal villi and crypt depth; reduced the serum levels of FITC-dextran and D-LA, as well as the DAO activity; and upregulated the colonic tissues of Occludin, Claudin-1, and ZO-1 mRNA and occludin protein expression. The number of goblet cells in the colon tissue of heat-stressed organisms increased in the presence of LTA, and the expression levels of Muc2, Muc4 mRNA, and Muc2 protein were upregulated. LTA increased the abundance of Bifidobacterium and Turicibacter, and decreased the abundance of Enterorhabdus and Desulfovibrio in the intestinal tract of heat-stressed organisms and restored gut microbiota homeostasis. LTA promoted the secretion of IL-4, IL-10, and sIgA and inhibited the secretion of TNF-α and IFN-γ in the colon of heat-stressed organisms. The expressions of Hsf1, Hsp70, Hsph1, TLR4, P38 MAPK, p-P65 NF-κB, MLCK mRNA, and proteins were downregulated by LTA in the colon of heat-stressed organisms. These results suggest that LTA protects the intestinal barrier in heat-stressed organisms by modulating multiple molecular pathways. Therefore, this study provides evidence on how tea-containing LTA treatments could be used to prevent and relieve intestinal problems related to heat stress.

Lung injuries induced by ozone exposure in female mice: Potential roles of the gut and lung microbes.

Ozone (O3) is one of the most harmful pollutants affecting health. However, the potential effects of O3 exposure on microbes in the gut-lung axis related to lung injuries remain elusive. In this study, female mice were exposed to 0-, 0.5- and 1-ppm O3 for 28 days, followed by routine blood tests, lung function tests and histopathological examination of the colon, nasal cavity and lung. Mouse faeces and lungs were collected for 16s rRNA sequencing to assess the overall microbiological profile and screen for key differential enriched microbes (DEMs). The key DEMs in faecal samples were Butyricimonas, Rikenellaceae RC9 and Escherichia-Shigella, whereas those in lung samples were DNF00809, Fluviicola, Bryobacter, Family XII AD3011 group, Sharpea, MND1 and unclassified Phycisphaeraceae. After a search in microbe-disease databases, these key DEMs were found to be associated with lung diseases such as lung neoplasms, cystic fibrosis, pneumonia, chronic obstructive pulmonary disease, respiratory distress syndrome and bronchiectasis. Subsequently, we used transcriptomic data from Gene Expression Omnibus (GEO) with exposure conditions similar to those in this study to cross-reference with Comparative Toxicogenomic Database (CTD). Il-6 and Ccl2 were identified as the key causative genes and were validated. The findings of this study suggest that exposure to O3 leads to significant changes in the microbial composition of the gut and lungs. These changes are associated with increased levels of inflammatory factors in the lungs and impaired lung function, resulting in an increased risk of lung disease. Altogether, this study provides novel insights into the role of microbes present in the gut-lung axis in O3 exposure-induced lung injury.

Important roles of Hif1a in maternal or adult BPA exposure induced pancreatic injuries.

Bisphenol A (BPA) is a monomer to produce polycarbonate plastics and can be released into the environment through human activities, leading to its accumulation in animals, plants and humans through direct contact or environmental exposure. Epidemiological studies have reported that BPA exposure is associated with metabolic disorders. The pancreas is an important endocrine organ and plays an important role in metabolic disorders. To explore the possible long-term effects of BPA exposure on neonatal health, bioinformatic methods were used to identify differentially expressed genes (DEGs) by comparing the neonatal pancreas after maternal exposure to BPA with the adult pancreas after direct exposure to BPA. Two datasets about BPA exposure and pancreatic abnormality, GSE82175 and GSE126297 in Gene Expression Omnibus (GEO) at the National Center for Biotechnology Information (NCBI) were collected. Control (or BPA-exposed) offspring (maternal exposure) and Control (or BPA-exposed) adults (direct exposure) were defined as Control (or BPA) groups. The results showed that BPA disturbed the normal function of the pancreas in both offspring and adults, with offspring showing higher susceptibility to BPA than adults. Seventeen insulin secretion-related DEGs (Stxbp5l, Fam3d, Mia3, Igf1, Hif1a, Aqp1, Kif5b, Tiam1, Map4k4, Cyp51, Pde1c, Rab3c, Arntl, Clock, Edn3, Kcnb1, and Krt20) in the BPA group were identified, and 15 regulator DEGs (Zfp830, 4931431B13Rik, Egr1, Ddit4l, Cep55, G530011O06Rik, Hspa1b, Hspa1a, Cox6a2, Ibtk, Banf1, Slc35b2, Golt1b, Lrp8, and Pttg1) with opposite expression trends and a regulator gene Cerkl with the similar expression trend in the Control and BPA groups were identified. Hif1α might be an important molecular target for pancreatic cancer caused by BPA exposure, and pregnancy is a critical window of susceptibility to BPA exposure.

Synergistic effects of L-theanine and epigallocatechin gallate in alleviating ovalbumin allergy by regulating intestinal immunity through inhibition of mast cell degranulation.

Ovalbumin (OVA), a commonly consumed food protein, can cause severe allergies and intestinal immune disorders. L-Theanine (LTA) and epigallocatechin gallate (EGCG) regulate intestinal immunity. However, it is unclear whether an LTA and EGCG combined intervention can alleviate OVA allergy (OVA-A) by modulating intestinal-specific immunity, and it is unknown whether there is a synergistic effect between LTA and EGCG. Therefore, we treated BALB/c OVA-sensitized mice with LTA, EGCG, or a combination of both (LTA + EGCG) to investigate the effects of LTA and EGCG on intestinal-specific immunity regulation and underlying mechanisms. Female mice were intraperitoneally injected with OVA to establish OVA-sensitive mouse models. MLEO LTA + EGCG (20 mg kg-1 d-1 LTA + 80 mg kg-1 d-1 EGCG) and HLEO (30 mg kg-1 d-1 LTA + 120 mg kg-1 d-1 EGCG) exerted more beneficial effects on alleviating OVA-A (weight gain, allergy score, jejunum structure, mast cell [MC] degranulation, thymus and spleen indices) than LTA or EGCG alone (p < 0.01). Based on the alleviation of OVA-A by LTA + EGCG, we selected MLEO mice for 16S rDNA, flow cytometry, and western blot analyses. The 16S rDNA results showed that MLEO increased the abundance of Lactobacillaceae, Lachnospiraceae, and Ruminococcaceae, and decreased that of Helicobacteraceae (p < 0.01). The flow cytometry and western blotting results indicated that MLEO reduced the number of dendritic cells available to capture OVA, thereby lowering the Th2 immune response and decreasing the IL-4 and IL-13 levels. Meanwhile, the attenuation of the Th2 immune response inhibits the cross-linking of OVA and FcεRI, thus reducing MC degranulation and decreasing the serum HIS and mMCPT-1 levels through the FcεRI/Btk/PLCγ signaling pathway. LTA + EGCG also inhibits the Th2 immune response through the FcεRI/Lyn/Syk/PI3K/AKT signaling pathway and decreases the serum IL-4 and IL-13 levels. Notably, LTA + EGCG promotes the Treg and Th1 immune responses and inhibits the Th17 immune response, altering the levels of the corresponding cytokines. Therefore, LTA + EGCG can synergistically alleviate OVA-A by regulating intestinal immunity through MC degranulation inhibition.

L-Theanine attenuates heat stress-induced proteotoxicity and alterations in carbohydrate and lipid metabolism via heat shock factor 1.

Extreme heat caused by global warming accelerated the frequency of heat stress (HS). Proteotoxic stress induced by the aggregation of misfolded proteins and metabolic stress triggered by alterations in the metabolism were observed during HS. The activation of heat shock factor 1 (Hsf1) and its interaction with adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) are critical in addressing proteotoxicity and metabolic stress in heat-stressed organisms. Previous studies have shown that L-theanine (LTA) can regulate nutrient metabolism through the AMPK pathway and can alleviate HS. Therefore, we hypothesize that LTA may help in restoring homeostasis by regulating nutrient metabolism under HS. Here, we investigated the effects of LTA on nutrient metabolism in heat-stressed rats and characterized the underlying mechanisms using RNA sequencing and metabonomics. The results showed that LTA alleviated HS-induced liver damage, promoted body weight gain, decreased serum cortisol and enhanced the total protein content. Besides, it regulated the expression of genes related to carbohydrate, lipid and amino acid metabolism and altered metabolite levels. Moreover, LTA inhibited the expression of Hsf1 and heat shock protein 70 (Hsp70), promoted AMPK phosphorylation and the expression of glucose-6-phosphatase catalytic subunit 1 (G6pc), and inhibited the phosphorylation of acetyl-CoA carboxylase 1 (ACC1) in heat-stressed rats. Mechanistically, LTA alleviated HS-induced proteotoxic stress by acting on Hsf1/Hsp70; simultaneously, it promoted AMPK phosphorylation by suppressing Hsf1 expression, which in turn inhibited fatty acid synthesis and hepatic gluconeogenesis, thus alleviating HS-induced metabolic stress. These results suggest that LTA regulates nutrient metabolism through Hsf1/AMPK and alleviates HS-induced proteotoxicity via Hsf1/Hsp70.

Sleep Deprivation and Heart Rate Variability in Healthy Volunteers: Effects of REM and SWS Sleep Deprivation.

Objective: Using PSG-guided acute selective REM/SWS sleep deprivation in volunteers, this study examined the effects of sleep deprivation on the cardiovascular and autonomic nervous systems, as well as the relationship between cardiac neuromodulation homeostasis and cardiovascular disease. Methods: An experiment was conducted using 30 healthy volunteers (male : female = 1 : 1, aged 26.33 ± 4.5 years) divided into groups for sleep deprivation of SWS and REM sleep, and then, each group was crossed over for normal sleep (2 days) and repeated sleep deprivation (1 day, 3 times). During the study period, PSG and ELECTRO ECG monitoring were conducted, and five-minute frequency domain parameters and blood pressure values were measured before and after sleep deprivation. Results: Changes in VLF, LFnu, LF/HF, HF, and HFnu after SWS sleep deprivation were statistically significant (P < 0.05), but not LF (P = 0.063). Changes in VLF, LF, HF, LF/HF, LFnu, and HFnu after REM sleep deprivation were not statistically significant (P > 0.05). Conclusions: An increase in sympathetic nerve activity results from sleep deprivation and sudden awakening from SWS sleep is associated with a greater risk of cardiovascular disease.

L-Theanine alleviates heat stress-induced impairment of immune function by regulating the p38 MAPK signalling pathway in mice.

With the current trend of global warming, heat stress-induced impairment could seriously endanger human health. L-Theanine is a non-protein amino acid in tea with various biological activities, including immunoregulatory, anti-anxiety, and anti-oxidation. However, its effect on immune function under heat stress and the underlying mechanism are currently unclear. In this study, male BALB/c mice were used as experimental objects to explore the effect of L-theanine on heat stress-induced changes in immune function and its mechanism. Three doses of L-theanine were used: low (100 mg kg-1 d-1), medium (200 mg kg-1 d-1), and high (400 mg kg-1 d-1). Treatment with L-theanine could attenuate the heat stress-induced reductions in body weight and feed intake in mice, alleviate damage in the liver and jejunum, and inhibit the inflammatory factors IL-6, IL-1ß, and TNF-α. Aspartate aminotransferase and alanine transaminase activity levels and the malondialdehyde content decreased, while the IgA, IgM, and IgG contents increased in response to L-theanine. It is possible that L-theanine affects the P38 signalling pathway and inhibits the increase in p-P65/P65 caused by the overexpression of HSP27 and regulation of PPAR-γ and Foxp3 proteins, thereby alleviating immune dysfunction caused by heat stress.

L-Theanine Mitigates the Harmful Effects of Excess High-Protein Diet in Rats by Regulating Protein Metabolism.

SCOPE: l-Theanine (LTA) is a non-protein amino acid that contributes to the flavor of tea and can regulate protein metabolism of healthy organisms. However, it is unknown whether it regulates protein metabolism in individuals on high-protein diets (HPDs). METHODS AND RESULTS: Here, Sprague-Dawley rats are fed HPDs with different protein supply ratios and administered a diverse dose of LTA for 40 days. Results show that HPDs with an energy supply ratio from protein >40% impair the liver and kidneys, elevate serum ammonia and urea nitrogen, induce amino acid (AA) catabolism, and promote fatty acid (FA) synthesis via FA-binding protein 5 (Fabp5) and acetyl-CoA carboxylase 1 (ACC1). LTA intervention alleviates HPD-induced hepatic and renal injury and improves serum biochemical indices. It increases hepatic free AA content and inhibits FA synthesis by downregulating Fabp5 and ACC1. It promotes protein synthesis by acting on the mammalian target of rapamycin (mTOR) pathway, thereby alleviating HPD-induced metabolic disorders. CONCLUSIONS: This study demonstrates that LTA mitigates kidney and liver damage induced by long-term excess HPDs by regulating protein metabolism.

L-theanine regulates the immune function of SD rats fed high-protein diets through the FABP5/IL-6/STAT3/PPARα pathway.

The protein levels in a diet are correlated with immunity but the long-term intake of excessive protein can compromise various aspects of health. L-theanine regulates immunity and protein metabolism; however, how its regulatory immunity effects under a high-protein diet are unclear. We used proteomics, metabonomics, and western blotting to analyze the effects of diets with different protein levels on immune function in rats to determine the role of L-theanine in immunity under a high-protein diet. The long-term intake of high-protein diets (≥40% protein) promoted oxidative imbalance and inflammation. These were alleviated by L-theanine. High-protein diets inhibited peroxisome proliferator-activated receptor (PPAR)α expression through the interleukin (IL)-6/signal transducer and activator of transcription (STAT)3 pathway and mediated inflammation. L-theanine downregulated anti-fatty acid-binding protein 5 (FABP5), inhibited the IL-6/STAT3 axis, and reduced high-protein diet-induced PPARα inhibition. Therefore, L-theanine alleviates the adverse effects of high-protein diets via the FABP5/IL-6/STAT3/PPARα pathway and regulates the immunity of normally fed rats through the epoxide hydrolase (EPHX)2/nuclear factor-kappa B inhibitor (IκB)α/triggering receptor expressed on myeloid cells (TREM)1 axis.