Naringin mitigates LPS-induced intestinal barrier injury in mice

Fucoxanthin alleviates lipopolysaccharide-induced intestinal barrier injury in mice

The aim of this study was to evaluate the preventive role and underlying mechanisms of fucoxanthin (Fx) on lipopolysaccharide (LPS)-induced intestinal barrier injury in mice. Our results demonstrated that the oral administration of Fx (50 and 200 mg per kg body weight per day) for consecutive 7 days significantly alleviated the severity of LPS-induced intestinal barrier injury in mice, as evidenced by attenuating body weight loss, improving intestinal permeability, and ameliorating intestinal morphological damage such as reduction in the ratio of the villus length to the crypt depth (V/C), intestinal epithelium distortion, goblet cell depletion, and low mucin 2 (MUC2) expression. Fx also significantly mitigated LPS-induced excessive apoptosis of intestinal epithelial cells (IECs) and curbed the decrease of tight junction proteins including claudin-1, occludin, and zonula occludens-1 in the ileum and colon. Additionally, Fx effectively alleviated LPS-induced extensive infiltration of macrophages and neutrophils into the intestinal mucosa, the overproduction of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin 1beta (IL-1β) and IL-6, and gasdermin D (GSDMD)-mediated pyroptosis of IECs. The underlying mechanisms might be associated with inhibiting the activation of nuclear factor-kappa B (NF-κB), mitogen-activated protein kinases (MAPKs) and nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome signaling pathways. Moreover, Fx also notably restrained intestinal reactive oxygen species (ROS), malondialdehyde and protein carbonylation levels in LPS-treated mice, and it might be mediated by activating the nuclear factor-erythroid 2 related factor 2 (Nrf2) signaling pathway. Overall, these findings indicated that Fx might be developed as a potential effective dietary supplement to prevent intestinal barrier injury.

Naringin Inhibits Macrophage Foam Cell Formation by Regulating Lipid Homeostasis and Metabolic Phenotype

Imbalances in lipid uptake and efflux and inflammation are major contributors to foam cell formation, which is considered a therapeutic target to protect against atherosclerosis. Naringin, a citrus flavonoid abundant in citrus fruits, has been reported to exert an antiatherogenic function, but its pharmacological mechanism is unclear. Naringin treatment effectively inhibits foam cell formation in THP-1 and RAW264.7 macrophages. In this study, mechanically, naringin maintained lipid homeostasis within macrophages through downregulation of the key genes for lipid uptake (MSR1 and CD36) and the upregulation of ABCA1, ABCG1 and SR-B1, which are responsible for cholesterol efflux. Meanwhile, naringin significantly decreased the cholesterol synthesis-related genes and increased the genes involved in cholesterol metabolism. Subsequently, the results showed that ox-LDL-induced macrophage inflammatory responses were inhibited by naringin by reducing the proinflammatory cytokines IL-1β, IL-6 and TNF-α, and increasing the anti- inflammatory cytokine IL-10, which was further verified by the downregulation of pro-inflammatory and chemokine-related genes. Additionally, we found that naringin reprogrammed the metabolic phenotypes of macrophages by suppressing glycolysis and promoting lipid oxidation metabolism to restore macrophage phenotypes and functions. These results suggest that naringin is a potential drug for the treatment of AS as it inhibits macrophage foam cell formation by regulating metabolic phenotypes and inflammation.

Abscisic acid ameliorates d-galactose -induced aging in mice by modulating AMPK-SIRT1-p53 pathway and intestinal flora

Abscisic acid (ABA) is a plant hormone with various biological activities. Aging is a natural process accompanied by cognitive and physiological decline, and aging and its associated diseases pose a serious threat to public health, but its mechanisms remain insufficient. Therefore, the purpose of this study was to investigate the ameliorative effects of ABA on d-galactose (D-Gal)-induced aging in mice and to delve into its molecular mechanisms. Aging model was es-tablished by theintraperitoneal injection of D-Gal. We evaluated the oxidative stress by measuring superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) levels in serum. Proteins content in brain were determined by Western blot. D-Gal-induced brain damage was monitored by measuring the levels of acetylcholinesterase (AChE) content and hematoxylin-eosin staining (H&E). To evaluate the effects of ABA on aging, we measured the gut microbiota. The results demonstrated that ABA increased SOD, CAT and AChE, decreased MDA level. H&E staining showed that ABA could improve D-Gal-induced damage. In addition, ABA regulated the B-cell-lymphoma-2 (BCL-2) family and Phosphatidylinositol 3-kinase/Protein kinase B (PI3K/AKT) signaling pathway, while further regulating the acetylation of p53 protein by modulating the AMPK pathway and activating SIRT1 protein, thereby inhibiting the apoptosis of brain neurons and thus regulating the aging process. Interestingly, ABA improved the ratio of intestinal bacteria involved in regulating multiple metabolic pathways in the aging process, such as Bacteroides, Firmicutes, Lactobacillus and Ak-kermansia. In conclusion, the present study suggests that ABA may be responsible for improving and delaying the aging process by enhancing antioxidant activity, anti-apoptosis and regulating intestinal flora.

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.

Dahuang zhechong pill ameliorates hepatic fibrosis by regulating gut microbiota and metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

DHZCP is a traditional Chinese medicinal formula in "The Synopsis of Prescriptions of the Golden Chamber" that has been often used in the treatment of hepatic disorders, gynecopathy and atherosclerosis. However, its underlying mechanisms in preventing hepatic fibrosis remain incompletely understood.

AIM OF THE STUDY

This study aims to explore the therapeutic efficacy and potential mechanism of DHZCP in a CCL4-induced experimental hepatic fibrosis rat model.

MATERIALS AND METHODS

DHZCP was orally administered at doses of 0.168, 0.084 and 0.042 g⋅kg-1⋅d-1 in a CCL4-induced hepatic fibrosis model using SD rats. Histopathology, immunohistochemistry and biochemical analysis, ELISA, Flow cytometry, WB, RT-PCR, 16 S rRNA, and untargeted metabolomic analysis were used to determine the therapeutic effects and mechanisms of DHZCP in the treatment of CCL4-induced hepatic fibrosis.

RESULTS

Pharmacodynamically, DHZCP inhibited ALT and AST, improved liver function, decreased NF-κB, TNF-α and IL-6 in liver tissue, indicating its role in inhibiting CCL4-induced liver inflammation. Most importantly, it reduces the level of fibrosis in serum and liver tissue. Histological analysis also showed that DHZCP could effectively inhibit inflammatory cytokine infiltration and excessive collagen deposition. Mechanistically, DHZCP regulates gut microbiota, improves the proportion of firmicutes and bacteroidota at the phylum level, and increases the abundance of beneficial bacteria at the genus level, such as muribagulaceae unclassified, prevotella, alloprevotella, closteriales unclassified, lachnospiraceae unclassified and phascolarctobacterium. Instead, it reduced the abundance of two harmful bacteria, desulfovibrio and colidextribacter. Four types of metabolites such as hydrocarbons, organic nitrogen compounds, organic oxygen compounds, and organosulfur compounds were added. Furthermore, DHZCP was found to reduce the damage of intestinal barrier caused by changes in gut microbiota and metabolites.

CONCLUSION

DHZCP is an effective inhibitor of hepatic fibrosis by regulating gut microbiota and metabolites, improving the integrity of the intestinal barrier.

Protective Effect of the Naringin-Chitooligosaccharide Complex on Lipopolysaccharide-Induced Systematic Inflammatory Response Syndrome Model in Mice

Naringin is one of the common flavonoids in grapefruit, which has anti-cancer, antioxidant, and anti-inflammatory activities. However, its poor solubility limits its wide application. Therefore, the aim of this study is to investigate the anti-inflammatory effect of naringin combined with chitooligosaccharides with good biocompatibility by constructing a mouse model of systemic inflammatory response syndrome (SIRS). The results showed that the naringin-chitooligosaccharide (NG-COS) complex significantly inhibited lipopolysaccharide (LPS)-induced weight loss, reduced food intake, tissue inflammatory infiltration, and proinflammatory cytokines IL-6, TNF-α, INF-γ, and IL-1β levels. The complex also significantly affected the content of malondialdehyde and the activities of MPO, SOD, and GSH in the liver, spleen, lungs, and serum of mice with systemic inflammation. In addition, NG-COS significantly inhibited the mRNA expression of inflammatory factors in the TLR4/NF-κB signaling pathway. Principal component analysis showed that the complexes could inhibit LPS-induced systemic inflammation in mice, and the effect was significantly better than that of naringin and chitooligosaccharides alone. This study explored the synergistic effects of chitosan and naringin in reducing inflammation and could contribute to the development of novel biomedical interventions.

Protective effect of naringin against radiation-induced heart disease in rats via Sirt1/NF-κB signaling pathway and endoplasmic reticulum stress

This study was designed to explore the protective effect and mechanism of naringin (NG) on radiation-induced heart disease (RIHD) in rats. Rats were divided into four x-ray (XR) irradiation groups with different absorbed doses (0/10/15/20 Gy), or into three groups (control, XR, and XR + NG groups). Subsequently, the ultrasonic diagnostic apparatus was adopted to assess and compare the left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), left ventricular internal diameter at end diastole (LVIDd), and left ventricular internal diameter at end systole (LVIDs) in rats. Hematoxylin-eosin (H&E) staining and Masson staining were applied to detect the pathological damage and fibrosis of heart tissue. Western blot was used to measure the expression levels of myocardial fibrosis-related proteins, endoplasmic reticulum stress-related proteins, and Sirt1 (silent information regulator 1)/NF-κB (nuclear factor kappa-B) signaling pathway-related proteins in cardiac tissues. Additionally, enzyme-linked immunosorbent assay was utilized to detect the activities of pro-inflammatory cytokines, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) in cardiac tissue. The results showed that NG treatment significantly attenuated the 20 Gy XR-induced decline of LVEF and LVFS and the elevation of LVIDs. Cardiac tissue damage and fibrosis caused by 20 Gy XR were significant improved after NG treatment. Meanwhile, in rats irradiated by XR, marked downregulation was identified in the expressions of fibrosis-related proteins (Col I, collagen type I; α-SMA, α-smooth muscle actin; and TGF-β1, transforming growth factor-beta 1) and endoplasmic reticulum stress-related proteins (GRP78, glucose regulatory protein 78; CHOP, C/EBP homologous protein; ATF6, activating transcription factor 6; and caspase 12) after NG treatment. Moreover, NG treatment also inhibited the production of pro-inflammatory cytokines [interleukin-6, interleukin-1β, and monocyte chemoattractant protein-1 (MCP-1)], reduced the expression of MDA, and promoted the activities of SOD and CAT. Also, NG treatment promoted Sirt1 expression and inhibited p65 phosphorylation. Collectively, XR irradiation induced cardiac injury in rats in a dose-dependent manner. NG could improve the cardiac injury induced by XR irradiation by inhibiting endoplasmic reticulum stress and activating Sirt1/NF-κB signaling pathway.

Protective role of Cecropin AD against LPS-induced intestinal mucosal injury in chickens

Introduction

Cecropin AD (CAD), a renowned antimicrobial peptide, has shown promising potential in treating various bacterial infections. This study investigates the protective effects of CAD against lipopolysaccharide (LPS)-induced intestinal adversities in chickens.

Methods

Sixty SPF-grade chicks were divided into groups and exposed to different dosages of CAD, followed by LPS administration. The study assessed the impact of CAD on intestinal mucosal injury markers, oxidative stress, and inflammation.

Results

LPS significantly increased Diamine oxidase (DAO) and D-lactate (D-LA) levels, both indicators of intestinal mucosal injury. CAD treatment substantially attenuated these elevations, particularly at higher dosages. Additionally, CAD markedly reduced oxidative stress in intestinal tissues, as shown by normalized antioxidant levels and decreased reactive oxygen species. Histological analysis supported these findings, showing better-preserved villi structures in CAD-treated groups. Furthermore, CAD significantly reduced IL-6 and IL-8 expression post-LPS stimulation and effectively regulated the NLRP3 inflammasome pathway, decreasing associated factors like NLRP3, Caspase-1, IL-1b, and IL-18.

Discussion

The study demonstrates CAD's therapeutic potential in alleviating LPS-induced intestinal injuries. The protective effects are primarily attributed to its anti-inflammatory and antioxidative actions and modulation of the NLRP3 inflammasome pathway.

Inhibitory effect of Portulaca oleracea L. aqueous extract and juice on NLRP3 inflammasome activation in an ulcerative colitis mouse model

Portulaca oleracea L. (PO) is an edible and medicinal plant used for treating gastrointestinal diseases. However, the effects of PO on ulcerative colitis (UC) and underlying mechanisms remain unclear. This study investigated the effects of PO aqueous extract (POE) and PO juice (PJ) on dextran sulfate sodium (DSS)-induced UC in a mouse model and attempted to unravel their underlying mechanisms. The results revealed that PJ contains more bioactive compounds and has more overlapping targets with UC than POE. Both POE and PJ effectively reduced Disease Activity Index scores and inflammatory cell infiltration in the UC mouse model, but PJ had a better effect than POE. Furthermore, PJ inhibited pyroptosis by decreasing the expression of the NLRP3 inflammasome, while also repairing the dysfunction of the intestinal barrier by upregulating the expression of tight junction proteins. Therefore, based on the study findings, we concluded that PJ can improve DSS-induced UC and may suppress pyroptosis by interfering with the activation of the NLRP3 inflammasome.

The combination of metagenome and metabolome to compare the differential effects and mechanisms of fructose and sucrose on the metabolic disorders and gut microbiota in vitro and in vivo

Sucrose and fructose are the most commonly used sweeteners in the modern food industry, but there are few comparative studies on the mechanisms by which fructose and sucrose affect host health. The aim of the present study was to explain the different effects of fructose and sucrose on host metabolism from the perspective of gut microbiota. Mice were fed for 16 weeks with normal drinking water (CON), 30% fructose drinking water (CF) and 30% sucrose drinking water (SUC). Compared with fructose treatment, sucrose caused significantly higher weight gain, epididymal fat deposition, hepatic steatosis, and jejunum histological injury. Sucrose increased the abundance of LPS-producing bacteria which was positively correlated with obesity traits, while fructose increased the abundance of Lactobacillus. An in vitro fermentation experiment also showed that fructose increased the abundance of Lactobacillus, while sucrose increased the abundance of Klebsiella and Escherichia. In addition, combined with microbial functional analysis and metabolomics data, fructose led to the enhancement of carbohydrate metabolism and TCA cycle capacity, and increased the production of glutamate. The cross-cooperation network greatly influenced the microbiota (Klebsiella, Lactobacillus), metabolites (glutamate, fructose 1,6-biosphosphate, citric acid), and genes encoding enzymes (pyruvate kinase, 6-phosphofructokinase 1, fructokinase, lactate dehydrogenase, aconitate hydratase, isocitrate dehydrogenase 3), suggesting that they may be the key differential factors in the process of fructose and sucrose catabolism. Therefore, the changes in gut microbiome mediated by fructose and sucrose are important reasons for their differential effects on host health and metabolism.

L-theanine attenuates porcine intestinal tight junction damage induced by LPS via p38 MAPK/NLRP3 signaling in IPEC-J2 cells

L-theanine is a natural bioactive component in tea leaves and has anti-inflammatory effects. The study aimed to investigated the effects and underlying mechanisms of L-theanine on lipopolysaccharide (LPS)-induced intestinal tight junction damage in IPEC-J2 cells. Results showed that LPS induced tight junction damage by increasing reactive oxygen species production and lactate dehydrogenase (LDH) release and decreasing the mRNA expression of tight junction proteins related genes zonula occludens-1 (ZO-1, also known as Tjp1), Occludin and Claudin-1, while L-theanine reversed such an effect and attenuated the increase of p38 mitogen-activated protein kinase (p38 MAPK) mRNA expression. The p38 MAPK inhibitor (SB203580) attenuated the mRNA expression of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (Nlrp3) inflammasome and interleukin-1β (Il-1β), and increased the mRNA expression of Tjp1, Occludin and Claudin-1, which showed a similar effect with L-theanine. In addition, NLRP3 inhibitor MCC950 attenuated the Il-1β expression and LDH release, while increased the expression of tight-junction protein-related genes. In conclusion, L-theanine could protect LPS-induced intestinal tight junction damage by inhibiting the activation of p38 MAPK-mediated NLRP3 inflammasome pathway.

Pingwei San Ameliorates Spleen Deficiency-Induced Diarrhea through Intestinal Barrier Protection and Gut Microbiota Modulation

Pingwei San (PWS) has been used for more than a thousand years as a traditional Chinese medicine prescription for treating spleen-deficiency diarrhea (SDD). Nevertheless, the exact mechanism by which it exerts its antidiarrheal effects remains unclear. The objective of this investigation was to explore the antidiarrheal efficacy of PWS and its mechanism of action in SDD induced by Rhubarb. To this end, UHPLC-MS/MS was used to identify the chemical composition of PWS, while the body weight, fecal moisture content, and colon pathological alterations were used to evaluate the effects of PWS on the Rhubarb-induced rat model of SDD. Additionally, quantitative polymerase chain reaction (qPCR) and immunohistochemistry were employed to assess the expression of inflammatory factors, aquaporins (AQPs), and tight junction markers in the colon tissues. Furthermore, 16S rRNA was utilized to determine the impact of PWS on the intestinal flora of SDD rats. The findings revealed that PWS increased body weight, reduced fecal water content, and decreased inflammatory cell infiltration in the colon. It also promoted the expression of AQPs and tight junction markers and prevented the loss of colonic cup cells in SDD rats. In addition, PWS significantly increased the abundance of Prevotellaceae, Eubacterium_ruminantium_group, and Tuzzerella, while decreasing the abundance of Ruminococcus and Frisingicoccus in the feces of SDD rats. The LEfSe analysis revealed that Prevotella, Eubacterium_ruminantium_group, and Pantoea were relatively enriched in the PWS group. Overall, the findings of this study indicate that PWS exerted a therapeutic effect on Rhubarb-induced SDD in rats by both protecting the intestinal barrier and modulating the imbalanced intestinal microbiota.