PGAM5 is a key driver of mitochondrial dysfunction in experimental lung fibrosis.

RATIONALE: Mitochondrial homeostasis has recently emerged as a focal point in the pathophysiology of idiopathic pulmonary fibrosis (IPF), but conflicting data have been reported regarding its regulation. We speculated that phosphoglycerate mutase family member 5 (PGAM5), a mitochondrial protein at the intersection of multiple cell death and mitochondrial turnover pathways, might be involved in the pathogenesis of IPF. METHODS: PGAM5-deficient mice and human pulmonary epithelial cells were analyzed comparatively with PGAM5-proficient controls in a bleomycin-based model of pulmonary fibrogenesis. Mitochondria were visualized by confocal and transmission electron microscopy. Mitochondrial homeostasis was assessed using JC1 (ΔΨ) and flow cytometry. RESULTS: PGAM5 plays an important role in pulmonary fibrogenesis. Pgam5-/- mice displayed significantly attenuated lung fibrosis compared to controls. Complementary, in vitro studies demonstrated that PGAM5 impaired mitochondrial integrity on a functional and structural level independently of mtROS-production. On a molecular level, reduced mitophagy caused by PGAM5 deficiency improved mitochondrial homeostasis. CONCLUSIONS: Our study identifies PGAM5 as an important regulator of mitochondrial homeostasis in pulmonary fibrosis. Our data further indicate PGAM5-mediated mitophagy itself as a pivotal gateway event in the mediation of self-sustaining mitochondrial damage and membrane depolarization. Our work hereby highlights the importance of mitochondrial dynamics and identifies a potential therapeutic target that warrants further studies. Toxic agents lead to mitochondrial damage resulting in depolarization of the mitochondrial membrane potential (ΔΨ) which is a gateway event for the initiation of PGAM5-mediated mitophagy. PGAM5-mediated mitophagy in turn leads to a self-perpetuating escalation of ΔΨ depolarization. Loss of the mitophagy-based damage-enhancing loop under PGAM5-deficient conditions breaks this vicious cycle, leading to improved mitochondrial homeostasis.

Long-term outcomes of cyclosporin induction and ustekinumab maintenance combination therapy in patients with steroid-refractory acute severe ulcerative colitis.

Background: Effective management of patients with acute severe ulcerative colitis (ASUC) is a major challenge and there remains a paucity of available maintenance treatment options after efficacious cyclosporin induction therapy. Objectives: We investigated the long-term effectiveness and safety of cyclosporin and ustekinumab combination therapy in patients with steroid refractory ASUC. Design: Monocentric, prospective study. Methods: We included patients with steroid refractory ASUC with multiple failed prior advanced therapies, who were treated with cyclosporin and ustekinumab combination therapy. Results: Among the 11 included patients, 10 had prior failure to infliximab and 8 failed at least three previous biological therapies. The mean baseline Mayo and Lichtiger scores were 10.9 (9-12) and 13.3 (11-14), respectively. Ustekinumab was initiated 3.2 weeks (1-8) after initiation of cyclosporin treatment and combination therapy was continued for a mean of 11.5 (4-20) weeks. Clinical response was achieved in six patients at week 16 and clinical steroid-free clinical remission in five patients at week 48. Endoscopic remission was achieved in five patients at week 16 and together with histological remission in five patients at week 52. Intestinal ultrasound demonstrated mean bowel wall thickening in the sigmoid colon of 5.5 mm at baseline and 3.5 mm at week 52, respectively. Two patients had to undergo colectomy (mean 4.5 months, range 3-6) and three stopped ustekinumab therapy due to ineffectiveness. Overall, combination therapy was well tolerated. Conclusion: Combination of cyclosporin and ustekinumab therapy allowed nearly half of ASUC patients to reach clinical and endoscopic remission after 52 weeks, warranting further studies. Trial registration: Not applicable.

Effects of cyclosporin and ustekinumab combination therapy in acute severe ulcerative colitis In this study, we looked at how to treat patients with a severe form of ulcerative colitis, a type of inflammatory bowel disease, when the usual treatments don't work. We tested a combination of two drugs, cyclosporine and ustekinumab, to see if it could help these patients in the long term. We included eleven patients who had already tried many other treatments and didn't get better. Most of them had also tried a drug called infliximab and had failed at least three other biological therapies. At the start, these patients were very sick, with high scores on disease activity measures. We gave them ustekinumab in addtion after a therapy with cyclosporin had been started before. The combination therapy continued for an average of almost 12 weeks. After 16 weeks, six patients showed improvement in their symptoms, and five were able to stop taking steroids. Five patients also had their colon lining looking healthy again when we looked inside with a scope after 16 weeks. And after 52 weeks, five patients had normal colon lining and healthy tissue under the microscope. Ultrasound showed that the thickness of their colon wall had decreased. Unfortunately, two patients had to have surgery to remove their colon, and three had to stop taking ustekinumab because it didn't help them. Overall, the combination therapy was safe and well-tolerated. In conclusion, combining cyclosporin and ustekinumab helped about half of the patients with severe ulcerative colitis get better and have healthy colon lining after 52 weeks. This suggests that more research is needed to understand the benefits of this treatment in these patients.

Sustained submicromolar H2O2 levels induce hepcidin via signal transducer and activator of transcription 3 (STAT3).

The peptide hormone hepcidin regulates mammalian iron homeostasis by blocking ferroportin-mediated iron export from macrophages and the duodenum. During inflammation, hepcidin is strongly induced by interleukin 6, eventually leading to the anemia of chronic disease. Here we show that hepatoma cells and primary hepatocytes strongly up-regulate hepcidin when exposed to low concentrations of H(2)O(2) (0.3-6 µM), concentrations that are comparable with levels of H(2)O(2) released by inflammatory cells. In contrast, bolus treatment of H(2)O(2) has no effect at low concentrations and even suppresses hepcidin at concentrations of >50 µM. H(2)O(2) treatment synergistically stimulates hepcidin promoter activity in combination with recombinant interleukin-6 or bone morphogenetic protein-6 and in a manner that requires a functional STAT3-responsive element. The H(2)O(2)-mediated hepcidin induction requires STAT3 phosphorylation and is effectively blocked by siRNA-mediated STAT3 silencing, overexpression of SOCS3 (suppressor of cytokine signaling 3), and antioxidants such as N-acetylcysteine. Glycoprotein 130 (gp130) is required for H(2)O(2) responsiveness, and Janus kinase 1 (JAK1) is required for adequate basal signaling, whereas Janus kinase 2 (JAK2) is dispensable upstream of STAT3. Importantly, hepcidin levels are also increased by intracellular H(2)O(2) released from the respiratory chain in the presence of rotenone or antimycin A. Our results suggest a novel mechanism of hepcidin regulation by nanomolar levels of sustained H(2)O(2). Thus, similar to cytokines, H(2)O(2) provides an important regulatory link between inflammation and iron metabolism.

Multispectral optoacoustic tomography for the non-invasive identification of patients with severe anemia in vivo.

The immediate diagnosis of severe anemia is crucial for patient outcome. However, reliable non-invasive point-of-care diagnostic tools for e.g., ICU monitoring are currently lacking. Using an advanced Multispectral Optoacoustic Tomography (MSOT) research device, we first substantiated a strong positive correlation of MSOT-signal and absolute hemoglobin concentration ex vivo in blood samples. In a clinical exploratory proof-of-concept study, we then evaluated 19 patients with different severities of anemia and controls by non-invasive in vivo measurement of hemoglobin in the radial artery. Our approach proved excellent in identifying patients with severe anemia triggering RBC transfusion based on a strong positive correlation of MSOT-signal intensity and hemoglobin concentration for 700 nm single wavelength and HbR unmixed MSOT-parameter analysis. In conclusion, our study lays the foundation to further develop MSOT-based real-time quantitative perfusion analyses in follow-up preclinical and clinical imaging studies and as a promising diagnostic tool to improve patient care in the future. DRKS00021442.

Label-free analysis of inflammatory tissue remodeling in murine lung tissue based on multiphoton microscopy, Raman spectroscopy and machine learning.

Inflammatory fibrotic tissue remodeling can lead to severe morbidity. Histopathology grading requires extraction of biopsies and elaborate tissue processing. Label-free optical technologies can provide diagnostic readout without preparation and artificial stainings and show potential for in vivo applications. Here, we present an integration of Raman spectroscopy (RS) and multiphoton microscopy for joint investigation of the bio-chemical composition and morphological features related to cellular components and connective tissue. Both modalities show that collagen signatures were significantly increased in a murine fibrosis model. Furthermore, autofluorescence signatures assigned to immune cells show high correlation with disease severity. RS indicates increased levels of elastin and lipids. Further, we investigated the effect of joint data sets on prediction performance in machine learning models. Although binary classification did not benefit from adding more features, multi-class classification was improved by integrated data sets.

In vivo multi spectral colonoscopy in mice.

Multi- and hyperspectral endoscopy are possibilities to improve the endoscopic detection of neoplastic lesions in the colon and rectum during colonoscopy. However, most studies in this context are performed on histological samples/biopsies or ex vivo. This leads to the question if previous results can be transferred to an in vivo setting. Therefore, the current study evaluated the usefulness of multispectral endoscopy in identifying neoplastic lesions in the colon. The data set consists of 25 mice with colonic neoplastic lesions and the data analysis is performed by machine learning. Another question addressed was whether adding additional spatial features based on Gauss-Laguerre polynomials leads to an improved detection rate. As a result, detection of neoplastic lesions was achieved with an MCC of 0.47. Therefore, the classification accuracy of multispectral colonoscopy is comparable with hyperspectral colonoscopy in the same spectral range when additional spatial features are used. Moreover, this paper strongly supports the current path towards the application of multi/hyperspectral endoscopy in clinical settings and shows that the challenges from transferring results from ex vivo to in vivo endoscopy can be solved.

Review and Analysis of German Mobile Apps for Inflammatory Bowel Disease Management Using the Mobile Application Rating Scale: Systematic Search in App Stores and Content Analysis.

BACKGROUND: Patients suffering from inflammatory bowel disease (IBD) frequently need long-term medical treatment. Mobile apps promise to complement and improve IBD management, but so far there has been no scientific analysis of their quality. OBJECTIVE: This study evaluated the quality of German mobile apps targeting IBD patients and physicians treating IBD patients using the Mobile Application Rating Scale (MARS). METHODS: The German Apple App Store and Google Play Store were systematically searched to identify German IBD mobile apps for patient and physician use. MARS was used by 6 physicians (3 using Android smartphones and 3 using iPhones) to independently assess app quality. Apps were randomly assigned so that the 4 apps with the most downloads were rated by all raters and the remaining apps were rated by 1 Android and 1 iOS user. RESULTS: In total, we identified 1764 apps in the Apple App Store and Google Play Store. After removing apps that were not related to IBD (n=1386) or not available in German (n=317), 61 apps remained. After removing duplicates (n=3) and apps for congresses (n=7), journals (n=4), and clinical studies (n=6), as well as excluding apps that were available in only 1 of the 2 app stores (n=20) and apps that could only be used with an additional device (n=7), we included a total of 14 apps. The app "CED Dokumentation und Tipps" had the highest overall median MARS score at 4.11/5. On the whole, the median MARS scores of the 14 apps ranged between 2.38/5 and 4.11/5. As there was no significant difference between iPhone and Android raters, we used the Wilcoxon comparison test to calculate P values. CONCLUSIONS: The MARS ratings showed that the quality of German IBD apps varied. We also discovered a discrepancy between app store ratings and MARS ratings, highlighting the difficulty of assessing perceived app quality. Despite promising results from international studies, there is little evidence for the clinical benefits of German IBD apps. Clinical studies and patient inclusion in the app development process are needed to effectively implement mobile apps in routine care.

Autophagy in Cancer Therapy-Molecular Mechanisms and Current Clinical Advances.

Autophagy is a crucial general survival tactic of mammalian cells. It describes the capability of cells to disassemble and partially recycle cellular components (e.g., mitochondria) in case they are damaged and pose a risk to cell survival or simply if their resources are urgently needed elsewhere at the time. Autophagy-associated pathomechanisms have been increasingly recognized as important disease mechanisms in non-malignant (neurodegeneration, diffuse parenchymal lung disease) and malignant conditions alike. However, the overall consequences of autophagy for the organism depend particularly on the greater context in which autophagy occurs, such as the cell type or whether the cell is proliferating. In cancer, autophagy sustains cancer cell survival under challenging, i.e., resource-depleted, conditions. However, this leads to situations in which cancer cells are completely dependent on autophagy. Accordingly, autophagy represents a promising yet complex target in cancer treatment with therapeutically induced increase and decrease of autophagic flux as important therapeutic principles.

Successful cyclosporin and ustekinumab combination therapy in a patient with severe steroid-refractory ulcerative colitis.

The therapeutic management of patients with severe steroid-refractory ulcerative colitis still represents a critical clinical challenge. In this setting, cyclosporin is an effective and rapidly acting induction treatment that is applied in combination with maintenance therapeutic agents like thiopurines or vedolizumab. Here, we present the case of a 33-year-old ulcerative colitis patient with severe steroid-refractory ulcerative colitis who refused surgical intervention and previously demonstrated no long-term benefit to anti-TNF antibody, vedolizumab, cyclosporin, thiopurines or tofacitinib treatment. Intravenous cyclosporin therapy was re-initiated in the patient and, after signs of clinical response, therapy with ustekinumab was additionally applied. After 11 weeks of well tolerated cyclosporin and ustekinumab combination therapy, cyclosporin was discontinued upon clinical and endoscopic remission. Subsequently, ustekinumab treatment has been effective in maintaining remission during the follow-up period of 195 days.

Topical application of Chlorin e6-PVP (Ce6-PVP) for improved endoscopic detection of neoplastic lesions in a murine colitis-associated cancer model.

Screening colonoscopy is crucial in reducing the mortality of colorectal cancer. However, detecting adenomas against the backdrop of an inflamed mucosa (e.g. in ulcerative colitis) remains exceedingly difficult. Therefore, we aimed to improve neoplastic lesion detection by employing a fluorescence-based endoscopic approach. We used the well-established murine AOM/DSS model to induce inflammation-driven carcinogenesis in the colon. In our diagnostic approach, we evaluated Chlorin e6 polyvinylpyrrolidone (Ce6-PVP)-based fluorescence endoscopy in comparison to standard white-light endoscopy. A specialized pathologist then analyzed the histology of the detected lesions. Complementary in vitro studies were performed using human cell lines and a murine organoid system. Ce6-PVP-based fluorescence endoscopy had an improved detection rate of 100% (8/8) in detecting high-grade dysplasias and carcinomas over white-light detection alone with 75% (6/8). Trade-off for this superior detection rate was an increased rate of false positive lesions with an increase in the false discovery rate from 45% for white-light endoscopy to 81% for fluorescence endoscopy. We demonstrate in a proof-of-concept study that Ce6-PVP-based fluorescence endoscopy is a highly sensitive red flag technology to identify biopsy-worthy lesions in the colon.

Author Correction: Non-professional phagocytosis: a general feature of normal tissue cells.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Non-professional phagocytosis: a general feature of normal tissue cells.

Non-professional phagocytosis by cancer cells has been described for decades. Recently, non-professional phagocytosis by normal tissue cells has been reported, which prompted us to take a closer look at this phenomenon. Non-professional phagocytosis was studied by staining cultured cells with live-cell staining dyes or by staining paraffin-embedded tissues by immunohistochemistry. Here, we report that each of 21 normal tissue cell lines from seven different organs was capable of phagocytosis, including ex vivo cell cultures examined before the 3rd passage as well as the primary and virus-transformed cell lines. We extended our analysis to an in vivo setting, and we found the occurrence of non-professional phagocytosis in healthy skin biopsies immediately after resection. Using dystrophin immunohistochemistry for membrane staining, human post-infarction myocardial tissue was assessed. We found prominent signs of non-professional phagocytosis at the transition zone of healthy and infarcted myocardia. Taken together, our findings suggest that non-professional phagocytosis is a general feature of normal tissue cells.

Plasma concentrations of ascorbic acid in a cross section of the German population.

Objectives Vitamin C deficiency is considered extremely rare in modern industrialized countries. This study was performed to assess vitamin C concentrations in the German population. Methods As part of a consultant-patient seminar on nutrition and food intolerances, patients were asked to participate in this study on a voluntary basis. Blood samples were taken for analysis of serum vitamin C concentrations, and all patients were asked to complete a questionnaire. The vitamin C concentration was determined by high-performance liquid chromatography. Results Of approximately 300 patients attending the seminar, 188 (62.6%) consented to vitamin C blood sample analysis and 178 (59.3%) answered the questionnaire. The mean vitamin C concentration was 7.98 mg/L (range, 0.50-17.40; reference range, 5-15 mg/L). A low plasma level with vitamin C insufficiency (<5 mg/L) was found in 31 patients (17.4%), and a potential scorbutogenic deficiency (<1.5 mg/L) was found in 6 (3.3%). Conclusions Potential vitamin C insufficiency and deficiency is common. It is therefore possible, even in modern developed populations, that certain individuals may require a higher intake of vitamin C.