Succinate promotes pulmonary fibrosis through GPR91 and predicts death in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is believed to be associated with a notable disruption of cellular energy metabolism. By detecting the changes of energy metabolites in the serum of patients with pulmonary fibrosis, we aimed to investigate the diagnostic and prognostic value of energy metabolites in IPF, and further elucidated the mechanism of their involvement in pulmonary fibrosis. Through metabolomics research, it was discovered that the TCA cycle intermediates changed dramatically in IPF patients. In another validation cohort of 55 patients with IPF compared to 19 healthy controls, it was found that succinate, an intermediate product of TCA cycle, has diagnostic and prognostic value in IPF. The cut-off levels of serum succinate were 98.36 µM for distinguishing IPF from healthy controls (sensitivity, 83.64%; specificity, 63.16%; likelihood ratio, 2.27, respectively). Moreover, a high serum succinate level was independently associated with higher rates of disease progression (OR 13.087, 95%CI (2.819-60.761)) and mortality (HR 3.418, 95% CI (1.308-8.927)). In addition, accumulation of succinate and increased expression of the succinate receptor GPR91 were found in both IPF patients and BLM mouse models of pulmonary fibrosis. Reducing succinate accumulation in BLM mice alleviated pulmonary fibrosis and 21d mortality, while exogenous administration of succinate can aggravate pulmonary fibrosis in BLM mice. Furthermore, GPR91 deficiency protected against lung fibrosis caused by BLM. In vitro, succinate promoted the activation of lung fibroblasts by activating ERK pathway through GPR91. In summary, succinate is a promising biomarker for diagnosis and prognosis of IPF. The accumulation of succinate may promote fibroblast activation through GPR91 and pulmonary fibrosis.

Establishment and application of the BRP prognosis model for idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial lung disease. Clinical models to accurately evaluate the prognosis of IPF are currently lacking. This study aimed to construct an easy-to-use and robust prediction model for transplant-free survival (TFS) of IPF based on clinical and radiological information. METHODS: A multicenter prognostic study was conducted involving 166 IPF patients who were followed up for 3 years. The end point of follow-up was death or lung transplantation. Clinical information, lung function tests, and chest computed tomography (CT) scans were collected. Body composition quantification on CT was performed using 3D Slicer software. Risk factors in blood routine examination-radiology-pulmonary function (BRP) were identified by Cox regression and utilized to construct the "BRP Prognosis Model". The performance of the BRP model and the gender-age-physiology variables (GAP) model was compared using time-ROC curves, calibration curves, and decision curve analysis (DCA). Furthermore, histopathology fibrosis scores in clinical specimens were compared between the different risk stratifications identified by the BRP model. The correlations among body composition, lung function, serum inflammatory factors, and profibrotic factors were analyzed. RESULTS: Neutrophil percentage > 68.3%, pericardial adipose tissue (PAT) > 94.91 cm3, pectoralis muscle radiodensity (PMD) ≤ 36.24 HU, diffusing capacity of the lung for carbon monoxide/alveolar ventilation (DLCO/VA) ≤ 56.03%, and maximum vital capacity (VCmax) < 90.5% were identified as independent risk factors for poor TFS among patients with IPF. We constructed a BRP model, which showed superior accuracy, discrimination, and clinical practicability to the GAP model. Median TFS differed significantly among patients at different risk levels identified by the BRP model (low risk: TFS > 3 years; intermediate risk: TFS = 2-3 years; high risk: TFS ≈ 1 year). Patients with a high-risk stratification according to the BRP model had a higher fibrosis score on histopathology. Additionally, serum proinflammatory markers were positively correlated with visceral fat volume and infiltration. CONCLUSIONS: In this study, the BRP prognostic model of IPF was successfully constructed and validated. Compared with the commonly used GAP model, the BRP model had better performance and generalization with easily obtainable indicators. The BRP model is suitable for clinical promotion.

Single-use flexible bronchoscopes vs traditional reusable flexible bronchoscopes: a prospective controlled study.

BACKGROUND: Single-use flexible bronchoscopes(SFB) eliminate the risk of bronchoscopy-related infection compared with traditional reusable flexible bronchoscopes(RFB). At present, there is no comparative study between SFB and RFB in the aspects of biopsy and interventional therapy. This study aims to explore whether SFB can perform complex bronchoscopic procedures such as transbronchial biopsies just like RFB. METHODS: We conducted a prospective controlled study. A total of 45 patients who required bronchoscopic biopsy in our hospital from June 2022 to December 2022 were enrolled. The patients were divided into the SFB group and the RFB group, and routine bronchoscopy, bronchoalveolar lavage, and biopsy were performed respectively. Data on the time of routine bronchoscopy, the recovery rate of bronchoalveolar lavage fluid(BALF), biopsy time, and bleeding volume were collected. Then we used the two-sample t-test and the χ2 test to assess the performance differences between SFB and RFB. We also designed a questionnaire to compare the performance between SFB and RFB by different bronchoscope operators. RESULTS: The routine examination time of SFB and RFB was 3.40 ± 0.50 min and 3.55 ± 0.42 min, respectively. There was no significant difference between the two groups (P = 0.308). The recovery rate of BALF was (46.56 ± 8.22) % in the SFB group and (47.00 ± 8.07) in the RFB group, without a significant difference between the two groups(P = 0.863). The biopsy time was similar(4.67 ± 0.51 min VS 4.57 ± 0.45 min) in both groups, with no significant difference(P = 0.512). The positive biopsy rate was 100% in both groups, with no significant difference. Overall, the bronchoscope operators were generally satisfied with SFB. CONCLUSION: SFBs are non-inferior to RFBs in routine bronchoscopy, bronchoalveolar lavage, and biopsy. It is suggested that SFBs have a wider clinical application.

The Effect of an Essential Oil Blend on Growth Performance, Intestinal Health, and Microbiota in Early-Weaned Piglets.

Essential oils (EO) are promising feed additives for their antibacterial, antioxidant, and immune-enhancing abilities with low toxicity. Carvacrol, thymol, and cinnamaldehyde are commonly used to synthesize EO. However, few studies focus on combining these three EO in early-weaned piglets. In the present study, 24 piglets weaned at 21 d of age were randomly divided into 2 groups (6 replicate pens per group, 2 piglets per pen). The piglets were fed a basal diet (the control group) and a basal diet supplemented with 400 mg/kg EO (a blend consisting of carvacrol, thymol, and cinnamaldehyde, the EO group) for 28 days. At the end of the experiment, one piglet per pen was randomly chosen to be sacrificed. Growth performance, hematology, plasma biochemical indices, antioxidant capacity, intestinal epithelial development and immunity, colonic volatile fatty acids (VFA), and microbiota were determined. The results indicated that the diet supplemented with EO significantly improved average daily feed intake (ADFI, p < 0.01) and average daily gain (ADG, p < 0.05) in the day 0 to 28 period. EO supplementation led to a significant decrease in plasma lysozyme (p < 0.05) and cortisol levels (p < 0.01). Additionally, EO significantly promoted jejunal goblet cells in the villus, jejunal mucosa ZO-1 mRNA expression, ileal villus height, and ileal villus height/crypt depth ratio in piglets (p < 0.05). The ileal mucosal TLR4 and NFκB p-p65/p65 protein expression were significantly inhibited in the EO group (p < 0.05). Colonic digesta microbiota analysis revealed that bacteria involving the Erysipelotrichaceae family, Holdemanella genus, Phascolarctobacterium genus, and Vibrio genus were enriched in the EO group. In conclusion, these findings indicate that the EO blend improves ADG and ADFI in the day 0 to 28 period, as well as intestinal epithelial development and intestinal immunity in early-weaned piglets, which provides a theoretical basis for the combined use of EO in weaned piglets.

Study on the Mechanism of Sancao Tiaowei Decoction in the Treatment of MNNG-Induced Precancerous Lesions of Gastric Carcinoma Through Hedgehog Signaling Pathway.

Sancao Tiaowei Decoction (SCTWD), a traditional Chinese medicine created by Professor Chen Weijian, has been used in the prevention and treatment of precancerous lesions of gastric carcinoma (PLGC). However, its mechanism has not been made clear. This study aimed to evaluate the therapeutic effect of SCTWD on 1-methyl-3-nitro-1-nitrosoguanidine-induced PLGC in rats and the mechanism of this effect. We found that SCTWD effectively repaired gastric mucosal injury, reversed the process of PLGC, and inhibited the occurrence of gastric cancer to some extent. In the results of hematoxylin-eosin (HE) staining, the number and arrangement of mucosal glands and the number of mononuclear cells in the lamina propria were improved in varying degrees; the enzyme-linked immunosorbent assay (ELISA) showed that the PG I and PGR of the medication treatment group were significantly higher; a Reverse Transcription-Polymerase Chain Reaction (RT-PCR) test showed that SCTWD could significantly upregulate the expression levels of Shh, Ptch, and Gli-1 in the gastric tissue of rats. The immunohistochemical method showed that SCTWD could significantly upregulate the protein expressions of Shh, Gli-1, Smo, cyclin D1, CDKN2A/p16INK4a, and NF-κBP65 and could reduce the expression of Ptch at the same time. Through the preliminary analysis of 75 compounds screened by UPLC-Q-TOF-MS, the main components, such as organic acids, esters and anhydrides, flavonoids, phenols, tanshinones, and so on, have anti-inflammatory and anti-tumor pharmacological effects. The results of KEGG enrichment analysis showed that 5 signaling pathways related to this project were found, and 33 differential genes were presented to construct the interaction network. These results suggested that SCTWD had a good regulatory effect on PLGC and thus may have a multi-targeted effect; SCTWD can not only significantly improve the pathological changes of gastric mucosa in rats with PLGC but also exert a strong effect of the regulation of the hedgehog signaling pathway.

Yttrium chloride-induced cytotoxicity and DNA damage response via ROS generation and inhibition of Nrf2/PPARγ pathways in H9c2 cardiomyocytes.

Increasing exploration of rare-earth elements (REEs) has resulted in a high REEs' exposure risk. Owing to their persistence and accumulation of REEs in the environment, their adverse effects have caused widespread concern. However, limited toxicological data are available for the adverse effects of yttrium (Y) and its underlying mechanisms of action. In the present study, H9c2 cardiomyocytes were used in vitro model to investigate the cardiotoxicity of yttrium chloride (YCl3). Results show that YCl3 treatment resulted in reactive oxygen species (ROS) overproduction, decrease in ∆Ψm, and DNA damage. Mechanistically, we detected expression levels of protein in response to cellular DNA damage and antioxidative defense. Results indicated that the phosphorylation of histone H2AX remarkably increased in a dose-dependent manner. At a high YCl3-exposure concentration (120 µM), specific DNA damage sensors ATM/ATR-Chk1/Chk2 were significantly decreased. The protein levels of key antioxidant genes Nrf2/PPARγ/HO-1 were also remarkably inhabited. Additionally, the antioxidant N-acetyl-L-cysteine (NAC) pretreatment promoted the activation of antioxidative defense Nrf2/PPARγ signaling pathways, and prevented the production of cellular ROS, thus protecting the DNA from cleavage. Altogether, our findings suggest that YCl3 can induce DNA damage through causing intracellular ROS overproduction and inhibition of antioxidative defense, leading to cytotoxicity in H9c2 cardiomyocytes.

[Clinical value of biomarkers in diagnosis and treatment of idiopathic pulmonary fibrosis].

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia characterized by progressive accumulation of fibroblastic foci and destruction of the alveolar structure. Due to an incomplete understanding of the mechanism of the occurrence and progression of IPF, currently no effective means have been available for its early screening or treatment. With a poor overall prognosis, the patients with IPF have a median survival of only 2-4 years. In recent years, several studies have confirmed that dozens of molecules are involved in the development of IPF and can be used as potential biomarkers. These biomarkers play important roles in early diagnosis (such as SP-D, MMP-7, and osteopontin), prognostic evaluation (such as telomerase length, KL-6, mtDNA, HSP-70, LOXL2, CXCL13, miRNA, ICAM-1, and CCL18), and guiding treatment of IPF (such as TOLLIP rs3750920 genotype, SAMS score, and SP-D), and also provide potential therapeutic targets (such as TERT, TERR, RTEC, and PARN).

Bone Marrow-Derived Mesenchymal Stem Cells Restored High-Fat-Fed Induced Hyperinsulinemia in Rats at Early Stage of Type 2 Diabetes Mellitus.

Numerous studies have proposed the transplantation of mesenchymal stem cells (MSCs) in the treatment of typical type 2 diabetes mellitus (T2DM). We aimed to find a new strategy with MSC therapy at an early stage of T2DM to efficiently prevent the progressive deterioration of organic dysfunction. Using the high-fat-fed hyperinsulinemia rat model, we found that before the onset of typical T2DM, bone marrow-derived MSCs (BM-MSCs) significantly attenuated rising insulin with decline in glucose as well as restored lipometabolic disorder and liver dysfunction. BM-MSCs also favored the histological structure recovery and proliferative capacity of pancreatic islet cells. More importantly, BM-MSC administration successfully reversed the abnormal expression of insulin resistance-related proteins including GLUT4, phosphorylated insulin receptor substrate 1, and protein kinase Akt and proinflammatory cytokines IL-6 and TNFα in liver. These findings suggested that MSCs transplantation during hyperinsulinemia could prevent most potential risks of T2DM for patients.

Clinical features and prognosis analysis of 57 patients with primary tracheal tumors.

BACKGROUND: Primary tracheal tumor (PTT) is a rare disease with poor prognosis. Its clinical features are variable. Treatment strategies for patients with PTTs are not standardized. The purpose of this study was to explore the clinical features, management and prognosis of PTT. METHODS: From 2009 to 2019, 57 patients were diagnosed with PTTs at Xiangya Hospital, China. A retrospective review of their medical records was performed. RESULTS: Among the 57 patients, 8 (14.0%) had benign tumors and 49 (86.0%) had malignant. Squamous cell carcinoma (SCC) (n=20, 40.8%) and adenoid cystic carcinoma (ACC) (n=10, 20.4%) were the most common histologic types. Seven (87.5%) of the benign PTT patients underwent bronchoscopic intervention and had no further complications. The 5-year survival rate for malignant PTTs was 13.8%. Patients who had ACC tended to have better survival rates than those with SCC, although the difference was not statistically significant (P=0.104). Compared with tumors located in upper third of the trachea, tumors located in the lower portion showed worse survival (P=0.0003). Patients who underwent complete surgical resection had significantly better survival compared to non-surgical therapies (P=0.016). The combination of chemoradiotherapy and bronchoscopic intervention was better than chemoradiotherapy alone (P=0.028). CONCLUSIONS: Histologic type, tumor location and treatment approaches likely influence clinical outcomes. Within the cohort described here, complete surgical resection was the optimal therapy for PTTs. For unresectable malignant PTTS, chemoradiotherapy with bronchoscopic intervention was a superior modality. Given the poor 5-year survival of PTT, larger-scale, multi-center studies are warranted to validate our findings and identify optimal therapeutic interventions.

Effect of glucose, soya oil and glutamine on protein expression and mammalian target of rapamycin complex 1 pathway of jejunal crypt enterocytes in weaned piglets.

The present study was conducted to evaluate the effects of glucose, soya oil or glutamine on jejunal morphology, protein metabolism and protein expression of the mammalian target of rapamycin complex 1 (mTORC1) signalling pathway in jejunal villus or crypt compartment of piglets. Forty-two 21 d-weaned piglets were randomly allotted to one of the three isoenergetic diets formulated with glucose, soya oil or glutamine for 28 d. On day 14 or 28, the proteins in crypt enterocytes were analysed with isobaric tags for relative and absolute quantification and proteins involved in mTORC1 signalling pathway in villus or crypt compartment cells were determined by Western blotting. Our results showed no significant differences (P > 0·05) in jejunal morphology among the three treatments on day 14 or 28. The differentially expressed proteins mainly took part in a few network pathways, including antimicrobial or inflammatory response, cell death and survival, digestive system development and function and carbohydrate metabolism. On day 14 or 28, there were higher protein expression of eukaryotic initiation factor-4E binding protein-1 in jejunal crypt compartment of piglets supplemented with glucose or glutamine compared with soya oil. On day 28, higher protein expression of phosphor-mTOR in crypt compartment was observed in piglets supplemented with glucose compared with the soya oil. In conclusion, the isoenergetic glucose, soya oil or glutamine did not affect the jejunal morphology of piglets; however, they had different effects on the protein metabolism in crypt compartment. Compared with soya oil, glucose or glutamine may be better energy supplies for enterocytes in jejunal crypt compartment.

Identification of microRNA transcriptome reveals that miR-100 is involved in the renewal of porcine intestinal epithelial cells.

MicroRNAs play important roles in various cellular processes, including differentiation, proliferation and survival. Using a pig model, this study sought to identify the miRNAs responsible for crypt-villus axis renewal of the small intestinal epithelium. Compared to the villus upper cells, there were 15 up-regulated and 41 down-regulated miRNAs in the crypt cells of the jejunum. Notably, we found that miR-100 was expressed more in the villus upper cells than in the crypt cells, suggesting an effect on intestinal epithelium differentiation. Overexpression of miR-100 increased the activity of alkaline phosphatase, confirming that miR-100 promoted IPEC-J2 cell differentiation. MiR-100 can inhibit cell proliferation as evidenced by CCK-8 and cell cycle assay results. We also showed that miR-100 significantly inhibited the migration of IPEC-J2 cells and promoted cell apoptosis through caspase-3-dependent cleavage of Bcl-2. Furthermore, FGFR3 was identified as a potential target of miR-100 by bioinformatics analysis. We confirmed that overexpression of miR-100 suppressed FGFR3 expression in IPEC-J2 cells by directly targeting the FGFR3 3'-UTR. This is the first report of miRNAs acting on the renewal of the intestinal crypt-villus axis. Our results also showed that miR-100 promotes the differentiation and apoptosis, and inhibits the proliferation and migration of enterocytes of pigs.

Molecular cloning, characterization and expression analysis of Frizzled 6 in the small intestine of pigs (Sus scrofa).

Frizzled 6 (FZD6) encodes an integral membrane protein that functions in multiple signal transduction pathways, for example, as a receptor in Wnt/planar cell polarity (PCP) signaling pathway for polarized cell migration and organ morphogenesis. Mutations in FZD6 have been identified in a variety of tumors. In this study, the full-length cDNA of Sus scrofa FZD6 (Sfz6) was cloned and characterized. Nucleotide sequence analysis demonstrates that the Sfz6 gene encodes the 712 amino-acid (aa) protein with seven transmembrane domain. Tissue distribution analysis showed that Sfz6 mRNA is ubiquitously expressed in various tissues, being highest in kidney, moderate in jejunum, ileum, colon, liver, and spleen. However, FZD6 protein is highly expressed in the heart and there was no significant difference in other tissues. The relative abundance and localization of FZD6 protein in jejunum along the crypt-villus axis was determined by Western blot and immunohistochemical localization. The results show that in the jejunum, FZD6 protein is highly expressed in the villus and less in the crypt cells. Cellular proliferation and viability assays indicate that knockdown of FZD6 with small interfering RNAs (siRNA) significantly reduced the cell viability of the intestinal porcine enterocyte cells (IPEC-J2). Furthermore, qPCR and Western blot analysis revealed that expressions of ras-related C3 botulinum toxin substrate 1 (Rac1); ras homolog gene family member A (RhoA) and c-Jun N-terminal kinase 1 (JNK1), some components of PCP signaling pathway were upregulated (P < 0.05) by knockdown of FZD6 in IPEC-J2 cells. In conclusion, these results showed that FZD6 abundance in the villus was higher than that in crypt cells and knockdown of FZD6 induces PCP signal pathway components expression in IPEC-J2 cells. Our findings provide the foundation for further investigation into porcine FZD6 gene.

Knockdown of Akt1 promotes Akt2 upregulation and resistance to oxidative-stress-induced apoptosis through control of multiple signaling pathways.

The Akt signaling pathway plays a key role in promoting the survival of various types of cells from stress-induced apoptosis, and different members of the Akt family display distinct physiological roles. Previous studies have shown that in response to UV irradiation, Akt2 is sensitized to counteract the induced apoptosis. However, in response to oxidative stress such as hydrogen peroxide, it remains to be elucidated what member of the Akt family would be activated to initiate the signaling cascades leading to resistance of the induced apoptosis. In the present study, we present the first evidence that knockdown of Akt1 enhances cell survival under exposure to 50 µM H(2)O(2). This survival is derived from selective upregulation and activation of Akt2 but not Akt3, which initiates 3 major signaling cascades. First, murine double minute 2 (MDM2) is hyperphosphorylated, which promotes p53 degradation and attenuates its Ser-15 phosphorylation, significantly attenuating Bcl-2 homologous antagonist killer (Bak) upregulation. Second, Akt2 activation inactivates glycogen synthase kinase 3 beta (GSK-3ß) to promote stability of myeloid leukemia cell differentiation protein 1 (MCL-1). Finally, Akt2 activation promotes phosphorylation of FOXO3A toward cytosolic export and thus downregulates Bim expression. Overexpression of Bim enhances H(2)O(2)-induced apoptosis. Together, our results demonstrate that among the Akt family members, Akt2 is an essential kinase in counteracting oxidative-stress-induced apoptosis through multiple signaling pathways.