Diabetic kidney injury is an almost unavoidable complication in diabetic patients. The activation of macrophages with high glucose in the patient's body is a key factor in triggering diabetic kidney disease (DKD). Mogrosides are commonly used sweeteners, but their effects on diabetic kidney injury are still unclear. This study used THP-1 cell models and diabetic mouse models to examine the impacts and pathways of mogrosides in inhibiting hyperglycemia-activated macrophages and alleviating kidney damage. This study used high glucose (33.3 mmol/L) to induce activation of macrophage-like THP-1 cells for studying the anti-inflammatory mechanism of mogrosides. At the same time, a diabetic mouse model was prepared using a high-fat diet and intraperitoneal injection of streptozotocin in order to further study the effects of mogrosides on alleviating symptoms of DKD. Mogrosides can suppress the activation of macrophages and kidney damage in diabetic mice, and this anti-inflammatory effect seems to be mediated through the NF-κB/NLRP3/Caspase-1 axis in macrophages. Moreover, the metabolomic results revealed that the anti-inflammatory properties of mogrosides were associated with the modulation of glutamate metabolism and glycerophospholipid metabolism in macrophages. Our results indicated that supplementing diabetic patients with mogrosides may help inhibit inflammatory responses and prevent kidney damage.

5-Fluorouracil (5-FU) is a commonly used chemotherapy drug, but there is no effective prevention and treatment for the side effects of intestinal mucositis induced by 5-FU. Inulin is a type of fermentable dietary fiber, which is non-digestible, and can improve metabolic function by modulating intestinal microbiota. The current study is aimed at appraising the effect of inulin on 5-FU-induced intestinal mucositis in mice by non-targeted metabolomics. The results indicated that oral inulin significantly inhibited 5-FU-induced body weight loss and intestinal shortening in mice, inhibited NLRP3 inflammasome activation and IL-1 beta expression, and increased IL-10 and IgA expressions. Inulin could significantly reduce intestinal mucosal injury induced by 5-FU in mice and significantly affected the production of 27 different metabolites in mouse serum. These metabolites were closely related to glycerophospholipid metabolism and retinol metabolic pathways. The study provided a potential new method for the prevention and treatment of chemotherapeutic intestinal mucositis.

This study is aimed at assessing the impact of soluble dietary fiber inulin on the treatment of diabetes-related chronic inflammation and kidney injury in mice with type 2 diabetes (T2DM). The T2DM model was created by feeding the Institute of Cancer Research (ICR) mice a high-fat diet and intraperitoneally injecting them with streptozotocin (50 mg/kg for 5 consecutive days). The thirty-six ICR mice were divided into three dietary groups: the normal control (NC) group, the T2DM (DM) group, and the DM + inulin diet (INU) group. The INU group mice were given inulin at the dose of 500 mg/kg gavage daily until the end of the 12th week. After 12 weeks, the administration of inulin resulted in decreased serum levels of fasting blood glucose (FBG), low-density lipoprotein cholesterol (LDL-C), blood urea nitrogen (BUN), and creatinine (CRE). The administration of inulin not only ameliorated renal injury but also resulted in a reduction in the mRNA expressions of inflammatory factors in the spleen and serum oxidative stress levels, when compared to the DM group. Additionally, inulin treatment in mice with a T2DM model led to a significant increase in the concentrations of three primary short-chain fatty acids (SCFAs) (acetic acid, propionic acid, and butyric acid), while the concentration of advanced glycation end products (AGEs), a prominent inflammatory factor in diabetes, exhibited a significant decrease. The results of untargeted metabolomics indicate that inulin has the potential to alleviate inflammatory response and kidney damage in diabetic mice. This beneficial effect is attributed to its impact on various metabolic pathways, including glycerophospholipid metabolism, taurine and hypotaurine metabolism, arginine biosynthesis, and tryptophan metabolism. Consequently, oral inulin emerges as a promising treatment option for diabetes and kidney injury.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic disease in modern society. It is characterized by an accumulation of lipids in the liver and an excessive inflammatory response. Clinical trials have provided evidence that probiotics may prevent the onset and relapse of NAFLD. The aim of this study was to explore the effect of Lactiplantibacillus plantarum NKK20 strain (NKK20) on high-fat-diet-induced NAFLD in an ICR murine model and propose the underlying mechanism whereby NKK20 protects against NAFLD. The results showed that the administration of NKK20 ameliorated hepatocyte fatty degeneration, reduced total cholesterol and triglyceride concentrations, and alleviated inflammatory reactions in NAFLD mice. In addition, the 16S rRNA sequencing results indicated that NKK20 could decrease the abundance of Pseudomonas and Turicibacter and increase the abundance of Akkermansia in NAFLD mice. LC-MS/MS analysis showed that NKK20 could significantly increase the concentration of short-chain fatty acids (SCFAs) in the colon contents of mice. The obtained non-targeted metabolomics results revealed a significant difference between the metabolites in the colon contents of the NKK20 administration group and those in the high-fat diet group, in which a total of 11 different metabolites that were significantly affected by NKK20 were observed, and these metabolites were mainly involved in bile acid anabolism. UPLC-MS technical analysis revealed that NKK20 could change the concentrations of six conjugated and free bile acids in mouse liver. After being treated with NKK20, the concentrations of cholic acid, glycinocholic acid, and glycinodeoxycholic acid in livers of the NAFLD mice were significantly decreased, while the concentration of aminodeoxycholic acid was significantly increased. Thus, our findings indicate that NKK20 can regulate bile acid anabolism and promote the production of SCFA, which can inhibit inflammation and liver damage and thus prevent the development of NAFLD.

Nephropathy injury is a prevalent complication observed in individuals with diabetes, serving as a prominent contributor to end-stage renal disease, and the advanced glycation products (AGEs) are important factors that induce kidney injury in patients with diabetes. Addressing this condition remains a challenging aspect in clinical practice. The aim of this study was to explore the effects of Lactiplantibacillus plantarum NKK20 strain (NKK20) which protects against diabetic kidney disease (DKD) based on animal and cell models. The results showed that the NKK20 can significantly reduce renal inflammatory response, serum oxidative stress response, and AGE concentration in diabetic mice. After treatment with NKK20, the kidney damage of diabetic mice was significantly improved, and more importantly, the concentration of butyrate, a specific anti-inflammatory metabolite of intestinal flora in the stool of diabetic mice, was significantly increased. In addition, nontargeted metabolomics analysis showed a significant difference between the metabolites in the mouse serum contents of the NKK20 administration group and those in the nephropathy injury group, in which a total of 24 different metabolites that were significantly affected by NKK20 were observed, and these metabolites were mainly involved in glycerophospholipid metabolism and arachidonic acid metabolism. Also, the administration of butyrate to human kidney- (HK-) 2 cells that were stimulated by AGEs resulted in a significant upregulation of ZO-1, Occludin, and E-cadherin gene expressions and downregulation of α-SMA gene expression. This means that butyrate can maintain the tight junction structure of HK-2 cells and inhibit fibrosis. Butyrate also significantly inhibited the activation of PI3K/Akt pathway. These results indicate that NKK20 can treat kidney injury in diabetic mice by reducing blood glucose and AGE concentration and increasing butyrate production in the intestine. By inhibiting PI3K pathway activation in HK-2 cells, butyrate maintains a tight junction structure of renal tubule epithelial cells and inhibits renal tissue fibrosis. These results suggest that NKK20 is helpful to prevent and treat the occurrence and aggravation of diabetic kidney injury.

This study aims to evaluate the effect of berberine-based carbon quantum dots (Ber-CDs) on improving 5-fluorouracil (5-FU)-induced intestinal mucositis in C57BL/6 mice, and explored the mechanisms behind this effect. Thirty-two C57BL/6 mice were divided into four groups: normal control (NC), 5-FU-induced intestinal mucositis model (5-FU), 5-FU + Ber-CDs intervention (Ber-CDs), and 5-FU + native berberine intervention (Con-CDs). The Ber-CDs improved body weight loss in 5-FU-induced mice with intestinal mucositis compared to the 5-FU group. The expressions of IL-1β and NLRP3 in spleen and serum in Ber-CDs and Con-Ber groups were significantly lower than those in the 5-FU group, and the decrease was more significant in the Ber-CDs group. The expressions of IgA and IL-10 in the Ber-CDs and Con-Ber groups were higher than those in the 5-FU group, but the up-regulation was more significant in the Ber-CDs group. Compared with the 5-FU group, the relative contents of Bifidobacterium, Lactobacillus and the three main SCFAs in the colon contents were significantly increased the Ber-CDs and Con-Ber groups. Compared with the Con-Ber group, the concentrations of the three main short-chain fatty acids in the Ber-CDs group were significantly increased. The expressions of Occludin and ZO-1 in intestinal mucosa in the Ber-CDs and Con-Ber groups were higher than those in the 5-FU group, and the expressions of Occludin and ZO-1 in the Ber-CDs group were more higher than that in the Con-Ber group. In addition, compared with the 5-FU group, the damage of intestinal mucosa tissue in the Ber-CDs and Con-Ber groups were recovered. In conclusion, berberine can attenuate intestinal barrier injury and oxidative stress in mice to mitigate 5-fluorouracil-induced intestinal mucositis, moreover, the above effects of Ber-CDs were more significant than those of native berberine. These results suggest that Ber-CDs may be a highly effective substitute for natural berberine.

The activation of the monocyte-macrophage system and the damage to the renal and pancreatic tissue are common complications in patients with diabetes induced by hyper-glycemia. This study aimed to evaluate the effect and mechanism of butyrate (NaB), a metabolite of intestinal flora, on inhibiting the inflammatory response of human monocyte-macrophages (THP-1 cells) induced by high glucose and the damage of pancreatic and renal tissue in diabetic mice. The results showed that high concentration glucose significantly up-regulated the expressions of IL-1β, TNF-α, and NLRP3 in THP-1 cells and mouse spleen, and that NaB could inhibit the overexpression of those genes. The abundance of Beclin-1, LC3B and reactive oxygen species (ROS) in THP-1 cells is increased due to the high glucose concentration, and NaB can inhibit the genes responsible for upregulating the expression. In diabetic mice, vacuolar degeneration of renal tubules was observed. Then we observed that some of the epithelial cells of the renal tubules were exfoliated and some formed tubules. NaB could alleviate these pathological lesions, but NaB cannot alleviate pancreatic injury. Our results indicated that NaB could be used for the prevention and adjuvant treatment of diabetic kidney injury.

Short-chain fatty acids (SCFAs) are important anti-inflammatory metabolites of intestinal flora. Oxidized low-density lipoprotein (ox-LDL)-induced macrophage activation is critical for the formation of atherosclerosis plaque. However, the association between SCFAs and ox-LDL-induced macrophage activation with respect to the formation of atherosclerosis plaque has not yet been elucidated. The present study investigated whether SCFAs (sodium acetate, sodium propionate, and sodium butyrate) can affect ox-LDL-induced macrophage activation and potential signaling pathways via regulation of the expression of the NLRP3/Caspase-1 pathway. Using human monocyte-macrophage (THP-1) cells as a model system, it was observed that ox-LDL not only induced cell inflammatory injury but also activated the NLRP3/Caspase-1 pathway. The exogenous supplementation of three SCFAs could significantly inhibit cell inflammatory injury induced by ox-LDL. Moreover, three SCFAs decreased the expression of IL-1β and TNF-α via the inactivation of the NLRP3/Caspase-1 pathway induced by ox-LDL. Furthermore, three SCFAs affected cellular metabolism in ox-LDL-induced macrophages, as detected by untargeted metabolomics analysis. The results of the present study indicated that three SCFAs inhibited ox-LDL-induced cell inflammatory injury by blocking the NLRP3/Caspase-1 pathway, thereby improving cellular metabolism. These findings may provide novel insights into the role of SCFA intervention in the progression of atherosclerotic plaque formation.

Objective: The objective is to explore the mechanism of inhibitory effect of three main SCFAs (acetate, propionate and butyrate) on inflammatory response of A549 cells. Methods: Human lung adenocarcinoma cells (A549 cells) were cultured, and were divided into normal control group (NC group), A. baumannii infection group (A. baumannii group), NF-κB inhibitor group (JSH group), A. baumannii infection + sodium acetate group (NaAc group), A. baumannii infection + sodium propionate group (NaPc group) and A. baumannii infection + sodium butyrate group (NaB group). Real-time quan-titative PCR was used to detect the mRNA expression of NLRP3, Caspase-1, IL-1β, IL-6, and TGF-β in A549 cells. Western blotting assay was used to de-termine the expression of autophagy and “pyroptosis” related proteins of NRLP3, cleaved-Caspase-1 (P20), GSDMD (P30), LC-3 and Beclin-1. At the same time, the expression of NF-κB p65 protein in nucleus and cytoplasm of A549 cells was detected. The level of oxygen species induced by A. baumannii. Compared with A. baumannii group, the expression of NF-κB p65 in nucleus was significantly decreased and the expression of NF-κB p65 in cytoplasm was significantly increased after 24 h pre-incubation with NaB, NaPc and NaAc, respectively. Conclusion: A. baumannii can induce inflammatory injury of pulmonary epithelial cells, and the three major SCFAs can inhibit the activation of NLRP3 inflammasome and the release of pro-inflammatory factors through NF-κB/ROS/NLRP3 pathway, which provides a new way for clinical prevention of severe inflammatory injury caused by A. baumannii infection.

This study evaluated the anti-inflammation effect of the three main short-chain fatty acids (SCFAs) on Acinetobacter baumannii-induced THP-1 cells. The three main SCFAs could inhibit A. baumannii-stimulated THP-1 cell NF-κB pathway activity and the expressions of NLRP3 inflamma-some and GSDMD, and increase autophagy. The three main SCFAs, especially the sodium butyrate (NaB), had the effect of down-regulation of ROS and TLR-2 expression in THP-1 cells. NaB and sodium propionate (NaPc), but not sodium acetate (NaAc), dramatically suppressed IL-1β and IFN-γ expression. The results indicated that NaB and NaPc could significantly inhibit the inflammation of THP-1 cells induced by A. baumannii, and the inhibitory effect was in the order of NaB > NaPc > NaAC. NaB and NaPc may inhibit inflammation through TLR-2/NF-κB/ROS/NLRP3 signaling pathway.

In recent years, sodium butyrate has gained increased attention for its numerous beneficial properties. However, whether sodium butyrate could alleviate inflammatory damage by macrophage activation and its underlying mechanism remains unclear. The present study used an advanced glycosylation products- (AGEs-) induced inflammatory damage model to study whether sodium butyrate could alleviate oxidative stress, inflammation, and metabolic dysfunction of human monocyte-macrophage originated THP-1 cells in a PI3K-dependent autophagy pathway. The results indicated that sodium butyrate alleviated the AGEs-induced oxidative stress, decreased the level of reactive oxygen species (ROS), increased malondialdehyde (MDA) and mRNA expression of pro-inflammatory cytokines of interleukin (IL)-1β and tumor necrosis factor (TNF)-α, and increased the content of superoxide dismutase (SOD). Sodium butyrate reduced the protein expression of the NLR family, pyrin domain-containing protein 3 (NLRP3) and Caspase-1, and decreased the nucleus expression of nuclear factor-kappaB (NF-κB). Sodium butyrate decreased the expression of light-chain-associated protein B (LC3B) and Beclin-1, and inhibited autophagy. Moreover, sodium butyrate inhibited the activation of the PI3K/Akt pathway in AGEs-induced THP-1 cells. In addition, the metabolomics analysis showed that sodium butyrate could affect the production of phosphatidylcholine, L-glutamic acid, UDP-N-acetylmuraminate, biotinyl-5'-AMP, and other metabolites. In summary, these results revealed that sodium butyrate inhibited autophagy and NLRP3 inflammasome activation by blocking the PI3K/Akt/NF-κB pathway, thereby alleviating oxidative stress, inflammation, and metabolic disorder induced by AGEs.

目的 探讨不同浓度的丁酸钠抑制氧化型低密度脂蛋白(Ox-LDL)诱发人单核巨噬THP-1细胞炎症反应能力及其机制.方法 分别使用终浓度为50、100、200、400、800μmol/L的丁酸钠预处理THP-1细胞24 h,再以终浓度为50 mg/L的Ox-LDL刺激THP-1细胞24 h,采用实时荧光定量PCR法和ELISA法检测IL-1β、TNF-α、IL-10和TGF-β表达量,实时荧光定量PCR法和免疫印迹法检测NLRP3和Caspase-1的表达量,免疫印迹法检测自噬相关蛋白LC3-Ⅱ和Beclin-1的表达量,以及NF-κB p65在细胞核和胞浆中的分布情况.本研究同时设置正常对照组和无丁酸钠预处理的Ox-LDL组.结果 与Ox-LDL组比较,分别经终浓度为200、400、800μmol/L丁酸钠预孵育后,THP-1细胞IL-10和TGF-β表达量显著升高(P<0.01);50、100、200、400μmol/L丁酸钠预处理组细胞TNF-α表达量明显下降(P<0.01);50和100μmol/L丁酸钠预处理组细胞IL-1β表达量明显下降(P<0.01);50、100、200、400、800μmol/L丁酸钠预处理组细胞Caspase-1表达量明显下降(P<0.01);仅400和800μmol/L丁酸钠预处理组细胞NLRP3蛋白表达量明显下降(P<0.01),其他浓度丁酸钠抑制效果不明显.Ox-LDL刺激后THP-1细胞NF-κB p65蛋白明显由细胞浆移位至细胞核内(P<0.01),而经50、100、200、400、800μmol/L丁酸钠预处理后,NF-κB p65蛋白核转位现象明显受到抑制(P<0.01).与Ox-LDL组比较,200、400、800μmol/L丁酸钠可以显著上调THP-1细胞Beclin-1表达量(P<0.01),50、100、200、400、800μmol/L丁酸钠可以显著上调LC3-Ⅱ表达量(P<0.01).结论 丁酸钠可以抑制由Ox-LDL诱发的THP-1细胞炎症反应,其可能的机制是通过上调THP-1细胞自噬水平,抑制THP-1细胞NF-κB信号通路和NLRP3炎症复合体活化而产生抗炎效果.本结果为采用"肠道微生物组-免疫炎症轴"理论干预高血脂患者体内慢性非可控性炎症提供了实验依据.

5-Fluorouracil (5-FU) is a used chemotherapy drug for cancer, and its main side effect is intestinal mucositis which causes chemotherapy to fail. It was known that short-chain fatty acids (SCFAs) can inhibit immune cell release of various proinflammatory factors and inhibit excessive intestinal inflammation. However, the inhibitory effect of SCFAs on 5-FU-induced intestinal mucositis is still unclear. To simulate the effects of SCFAs on immune and intestinal epithelial cells, the cells (THP-1 cells and Caco-2 cells) were pretreated with sodium acetate (NaAc), sodium propionate (NaPc) and sodium butyrate (NaB), then inflammation was induced by 5-FU. The expressions of reactive oxygen species (ROS), Beclin-1, LC3-II, NF-κB p65, NLRP3 inflammasome, proinflammatory/anti-inflammatory cytokines and mucosal tight junction proteins were determined. In our results, the three SCFAs could inhibit ROS expressions, NLRP3, Caspase-1, IL-1β, IL-6, IL-18, Beclin-1 and LC3-II, when induced by 5-FU. In a 5-FU-induced chemoentermuctis mouse model, Lactobacillus rhamnoides can increase the concentrations of three SCFAs in faeces and increase the concentrations of IL-1β, IL-6 and IgA in serum, and decrease the expressions of NLRP3 and IL-17 in spleen cells. The expressions of ZO-1 and Occludin in intestinal mucosa were significantly increased. These results indicated that the three SCFAs can effectively suppress the inflammation of THP-1 cells and Caco-2 cells and maintain tight junction integrity in intestinal mucosal epithelial cells.

The overactivation of macrophages causes chronic inflammatory diseases. Short-chain fatty acids (SCFAs), potential drugs for clinical treatment, are modulators of macrophage inflammatory reaction. Therefore, the modulation of macrophage-mediated cell activity is expected to become a new therapeutic strategy for inflammatory diseases caused by Mycoplasma pneumoniae. In this study, 2 kinds of SCFAs (propionate and butyrate) were found to have anti-inflammatory effects in M. pneumoniae-stimulated THP-1 cells inflammatory. They inhibited the expressions of IL-4, IL-6, ROS, and NLRP3 inflammasome, while enhancing the expressions of IL-10 and IFN-γ. Our study revealed these 2 agents to repress transcriptional activities of NF-κB, which are important modulators of inflammation. Meanwhile, SCFAs can significantly enhance the autophagy induced by M. pneumoniae. Considering that SCFAs have few side effects, they might be the promising adjuvant therapy for the prevention and/or treatment of various inflammatory diseases.

目的:研究3种主要短链脂肪酸(short-chain fatty acids,SCFAs)即乙酸钠、丙酸钠和丁酸钠,对5-氟尿嘧啶(5-Fluorouracil,5-FU)诱发人单核巨噬THP-1细胞炎症反应的影响及其可能机制.方法:将THP-1细胞分为5组:对照组,细胞未经任何处理;5-FU组,2.5 mmol/L 5-FU处理细胞24 h;5-FU+乙酸钠组、5-FU+丙酸钠组、5-FU+丁酸钠组,均经100μmol/L相应SCFAs预处理24 h,再加入2.5 mmol/L 5-FU处理24 h.采用qRT-PCR法检测细胞炎症相关因子mRNA表达量;ELISA法检测细胞上清液中IL-1β、IL-6和IL-10含量;蛋白质印迹法检测细胞Toll样受体9(TLR9)、NOD样受体家族3(NLRP3)、Caspase-1、LC3-Ⅱ、Beclin-1表达量,以及细胞核和胞质中核因子-κB(nuclear factor kappa B,NF-κB)p65蛋白表达量;流式细胞术检测细胞活性氧水平.结果:与对照组相比,5-FU组TLR9、NLRP3、Caspase-1、IL-1β、IL-6、LC3-Ⅱ、Beclin-1、胞核NF-κB p65蛋白表达量以及活性氧水平显著增加(P均<0.01).与5-FU组比较,5-FU+乙酸钠组TLR9表达量显著降低(P<0.01);5-FU+丙酸钠组IL-1β表达量以及活性氧水平显著降低(P<0.01);5-FU+丁酸钠组IL-1β表达量以及核内NF-κB p65蛋白表达量显著减少(P<0.01),而胞质内表达量显著增加(P<0.01);3种SCFAs预处理均可以显著降低NLRP3、Caspase-1、IL-6、LC3-Ⅱ及Beclin-1表达量(P<0.01),并增加抗炎因子IL-10表达量(P<0.01).结论:乙酸钠、丙酸钠和丁酸钠3种SCFAs可以显著抑制由5-FU诱发的THP-1细胞炎症反应,并抑制细胞自噬水平,减少细胞活性氧生成量,其可能是通过抑制TLR9/NF-κB/ROS途径产生抗炎作用.