A Potential Probiotic for Diarrhea: Clostridium tyrobutyricum Protects Against LPS-Induced Epithelial Dysfunction via IL-22 Produced By Th17 Cells in the Ileum.

Probiotics are clinically used for diarrhea and inflammatory bowel diseases in both humans and animals. Previous studies have shown that Clostridium tyrobutyricum (Ct) protects against intestinal dysfunction, while its regulatory function in the gut needs further investigation and the related mechanisms are still not fully elucidated. This study aims to further verify the protective function of Ct and reveal its underlying mechanisms in alleviating diarrhea and intestinal inflammation. Ct inhibited LPS-induced diarrhea and intestinal inflammation in the ileum. IL-22 was identified and the protective role of Ct in the ileum presented an IL-22-dependent manner according to the transcriptomic analysis and in vivo interference mice experiments. The flow cytometric analysis of immune cells in the ileum showed that Ct enhanced the proportions of Th17 cells in response to LPS. The results of in situ hybridization further verified that Ct triggered Th17 cells to produce IL-22, which combined with IL-22RA1 expressed in the epithelial cells. Moreover, Ct was unable to enhance the levels of short-chain fatty acids (SCFAs) in the ileum, suggesting that the protective role of Ct in the ileum was independent of SCFAs. This study uncovered the role of Ct in alleviating diarrhea and inflammation with the mechanism of stimulating Th17 cells in the lamina propria to produce IL-22, highlighting its potential application as a probiotic for diarrhea and inflammation in the ileum.

A Potential Prophylactic Probiotic for Inflammatory Bowel Disease: The Overall Investigation of Clostridium tyrobutyricum ATCC25755 Attenuates LPS-Induced Inflammation via Regulating Intestinal Immune Cells.

SCOPE: This study aims to roundly investigate whether Clostridium tyrobutyricum (Ct) alleviates inflammation via regulating immune cells in the small intestines. METHODS AND RESULTS: Mice are pre-treated with different concentrations of Ct follow by LPS stimulation. Ct maintains the mice body weight under inflammation. In response to LPS, 107 CFU mL-1 Ct decreases the mRNA expression of inflammatory cytokines in the duodenum, while 108 CFU mL-1 Ct reduces inflammatory cytokines expression in both duodenum and ileum and protected intestinal morphology. The small intestinal immune cells are analyzed using flow cytometry. Ct decreases the numbers of macrophages and mast cells in the intestines in response to LPS. In the duodenum, Ct enhances dentritic cells (DCs), regulatory T cells (Tregs), and T helper cell 17 (Th17) proportions. Ct decreases DCs and Tregs proportions, while enhances Th17 numbers in the ileum. The underlying mechanism of Ct in preventing inflammation may rely on the physiological immune cell composition of the intestines. In response to LPS, Ct may mainly stimulate Tregs via activating DCs in the duodenum while trigger Th17 cells in the ileum, thereby maintaining the intestinal homeostasis. CONCLUSION: Ct alleviates the LPS-induce inflammation via regulating different immune cell types in the small intestines, highlighting that Ct is a potential prophylactic probiotic in intestinal diseases.

Clostridium tyrobutyricum Protects against LPS-Induced Colonic Inflammation via IL-22 Signaling in Mice.

This study aimed to investigate the effects of Clostridium tyrobutyricum (C. tyrobutyricum) on colonic immunity and the role of IL-22 in the protective function of C. tyrobutyricum. Mice were supplemented with 108 CFU/mL C. tyrobutyricum daily for 20 days, followed by injecting with LPS for 24 h. In vivo interference of IL-22 via injecting with an adeno-associated virus was conducted to elucidate the role of IL-22 in C. tyrobutyricum attenuating colonic inflammation. The results showed that C. tyrobutyricum decreased the mRNA expression of IL-6 and IL-1ß. C. tyrobutyricum enhanced the mRNA expression of IL-22 and the expression of MUC2 in the colon. The in vivo interference results showed that C. tyrobutyricum enhanced the mRNA expression of IL-6 and IL-1ß while decreased the expression of MUC2 after knocking down IL-22. The flow cytometric analysis showed that C. tyrobutyricum decreased the proportions of macrophages, DCs, and mast cells and effectively regulated the proportion of Th17 cells, indicating that C. tyrobutyricum may stimulate the expression of IL-22 via regulating Th17 cells. Our study concluded that C. tyrobutyricum protected against LPS-induced colonic barrier dysfunction and inflammation via IL-22 signaling, suggesting that C. tyrobutyricum could be a potential probiotic in regulating colonic health.

Chitosan Oligosaccharide Attenuates Nonalcoholic Fatty Liver Disease Induced by High Fat Diet through Reducing Lipid Accumulation, Inflammation and Oxidative Stress in C57BL/6 Mice.

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease closely associated with metabolic syndrome, but there are no validated pharmacological therapies. The aim of this study was to investigate the effect of chitosan oligosaccharide (COS) on NAFLD. Mice were fed either a control diet or a high-fat diet (HFD) with or without COS (200 or 400 mg/kg body weight (BW)) by oral gavage for seven weeks. Administration with COS significantly lowered serum lipid levels in the HFD-fed mice. The hepatic lipid accumulation was significantly decreased by COS, which was attributed to decreased expressions of lipogenic genes and increased expressions of fatty ß-oxidation-related genes. Moreover, pro-inflammatory cytokines, neutrophils infiltration, and macrophage polarization were decreased by COS in the liver. Furthermore, COS ameliorated hepatic oxidative stress by activating the nuclear factor E2-related factor 2 (Nrf2) pathway and upregulating gene expressions of antioxidant enzymes. These beneficial effects were mediated by the activation of the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. Therefore, COS might be a potent dietary supplement to ameliorate NAFLD.

Coaxial technique-promoted diagnostic accuracy of CT-guided percutaneous cutting needle biopsy for small and deep lung lesions.

Coaxial technique is extensively applied to facilitate percutaneous lung lesion biopsy. However, the impact of coaxial technique on diagnostic accuracy remains undecided. We reviewed 485 patients who underwent percutaneous CT-guided needle biopsies of lung lesions in our hospital. All of these biopsies were performed using either a cutting needle alone (n = 268) or a cutting needle combined with a coaxial needle (n = 217). The diagnostic accuracy and complications resulting from the two techniques were then compared. The diagnostic accuracies of the two techniques were comparably high, at 98.2% (with coaxial technique) and 95.9% (without coaxial technique), p = 0.24. Subgroup analysis discovered that for patients with lesions measuring < 1.5 cm and needle path length ≥ 4 cm, the coaxial technique achieved a higher diagnostic accuracy (95.5% vs. 72.7%, p = 0.023). The biopsy was well tolerated in all of the patients. Pneumothorax occurred less often in patients who were biopsied with the coaxial technique (19 versus 43, p = 0.024). Thus, the application of the coaxial technique could improve diagnostic accuracy in patients with small and deep lung lesions, and could reduce the risk of pneumothorax. The combined use of cutting needles with coaxial needles is the preferred technique for performing percutaneous CT-guided lung biopsies.

Effect of Ku80 on the radiosensitization of cisplatin in the cervical carcinoma cell line HeLa.

Cisplatin chemotherapy in combination with radiotherapy is the primary therapeutic strategy for the treatment of cervical cancer; however, the underlying molecular mechanism for cisplatin radiosensitization remains unknown. The aim of the present study was to investigate the effect of Ku80, a DNA double-strand break (DSB) repair protein, on cisplatin radiosensitization in cervical cancer. The pre-established Ku80 suppression cervical cancer cell line HeLa/Ku80-siRNA and the normal HeLa cell line underwent 6 MV X-ray irradiation (6 Gy) individually or in combination with 5 µg/ml cisplatin treatment. Alterations in apoptosis, the cell cycle and γH2AX expression were detected. Following irradiation individually and combined with cisplatin, compared with normal HeLa cells, HeLa/Ku80-siRNAexhibited an increased rate of apoptosis (P<0.05). It was identified that the earlier cisplatin was administered following irradiation, the higher the rate of apoptosis. Cell cycle analysis indicated that, following irradiation combined with cisplatin, the cells were arrested in G1 and S phase rather than in G2/M phase following irradiation alone. Microscopic imaging of immunofluorescence staining and western blotting identified that HeLa/Ku80-siRNA cells exhibited more γH2AX foci remaining following treatment with irradiation and cisplatin, particularly in the group treated with 6 Gy irradiation for 1 h together with 23 h of exposure to cisplatin. Irradiation in combination with cisplatin promoted the apoptosis of HeLa cells in association with the inhibition of Ku80, and it was identified that the earlier cisplatin was administered following irradiation, the more apoptosis was induced. This maybe because irradiation combined with cisplatin is able to arrest cells in G1 and S phase to rapidly repair damaged DNA, and the lack of Ku80 induces the inability to repair DSB, resulting in increased apoptosis. The results of the present study suggest that Ku80 may be a potent molecular target in cisplatin radiosensitization.