Recent developments on BMPs and their antagonists in inflammatory bowel diseases

Intestinal epithelial cells in health and disease

This comprehensive review delves into the pivotal role of intestinal epithelial cells in the context of various diseases. It provides an in-depth analysis of the diverse types and functions of these cells, explores the influence of multiple signaling pathways on their differentiation, and elucidates their critical roles in a spectrum of diseases. The significance of the gastrointestinal tract in maintaining overall health is extremely important and cannot be exaggerated. This complex and elongated organ acts as a crucial link between the internal and external environments, making it vulnerable to various harmful influences. Preserving the normal structure and function of the gut is essential for well-being. Intestinal epithelial cells serve as the primary defense mechanism within the gastrointestinal tract and play a crucial role in preventing harmful substances from infiltrating the body. As the main components of the digestive system, they not only participate in the absorption and secretion of nutrients and the maintenance of barrier function but also play a pivotal role in immune defense. Therefore, the health of intestinal epithelial cells is of vital importance for overall health.

The protective role of PYY in intestinal mucosal defects induced by SATB2 deficiency in inflammatory bowel disease

Impaired colonic mucosal repair is a critical issue in inflammatory bowel diseases (IBD). SATB2 is essential for maintaining colonic epithelial homeostasis, but its role in mucosal repair is unclear. In this study, flow cytometry was used to assess SATB2's role in colonic epithelial repair in a radiation injury model. SATB2 knockout mice exhibited defective epithelial repair, with a marked reduction in goblet and enteroendocrine cells. Mechanistically, SATB2 directly regulated PPAR-γ transcription, and PYY was observed to translocate into the nucleus and promote the transcription of PPAR-γ target genes. In organoids derived from patients with Crohn's disease, PYY supplementation significantly improved epithelial regeneration, outperforming the PPAR-γ agonist rosiglitazone. In conclusion, SATB2 deficiency impairs colonic epithelial repair, which can be rescued by PYY through activation of PPAR-γ-dependent transcription. These findings suggest that PYY may serve as a promising therapeutic molecule to promote epithelial repair in IBD.

Emerging role of BMPs/BMPR2 signaling pathway in treatment for pulmonary fibrosis

Pulmonary fibrosis is a fatal and chronic lung disease that is characterized by accumulation of thickened scar in the lungs and impairment of gas exchange. The cases with unknown etiology are referred as idiopathic pulmonary fibrosis (IPF). There are currently no effective therapeutics to cure the disease; thus, the investigation of the pathogenesis of IPF is of great importance. Recent studies on bone morphogenic proteins (BMPs) and their receptors have indicated that reduction of BMP signaling in lungs may play a significant role in the development of lung fibrosis. BMPs are members of TGF-β superfamily, and they have been shown to play an anti-fibrotic role in combating TGF-β-mediated pathways. The impact of BMP receptors, in particular BMPR2, on pulmonary fibrosis is growing attraction to researchers. Previous studies on BMPR2 have often focused on pulmonary arterial hypertension (PAH). Given the strong clinical association between PAH and lung fibrosis, understanding BMPs/BMPR2-mediated signaling pathway is important for development of therapeutic strategies to treat IPF. In this review, we comprehensively review recent studies regarding the biological functions of BMPs and their receptors in lungs, especially focusing on their roles in the pathogenesis of pulmonary fibrosis and fibrosis resolution.

Current situation of sporotrichosis in China

Sporotrichosis, a mycosis resulting from cutaneous or subcutaneous infection with the dimorphic fungus Sporothrix, has been reported in China, particularly in the northeast region. In this review, we conducted a thorough examination of the recent advancements in sporotrichosis in China, encompassing aspects such as etiology, epidemiology, pathogenesis, clinical manifestations, diagnosis and treatment strategies. Within the Chinese context, fixed cutaneous sporotrichosis represents the prevailing clinical manifestation. Fungal culture stands as the gold standard for diagnosing sporotrichosis, while polymerase chain reaction techniques can enhance both the specificity and sensitivity of diagnosis. Besides conventional systemic antifungal agents, alternative modalities such as Chinese herbal medicines, photodynamic therapy and laser therapy show potential efficacy against sporotrichosis.

HT-2 mycotoxin and selenium deficiency: Effects on Femur development and integrity in Young mice

Kashin-Beck Disease (KBD), an osteoarticular disorder, is potentially influenced by several factors, among which selenium deficiency and HT-2 mycotoxin exposure are considered significant. However, the combined effect of these factors on femoral development remains unclear, Conducted over eight weeks on forty-eight male mice categorized into control, selenium-deficient, and HT-2 toxin-exposed groups, including dual-exposure sets, this study comprehensively monitored body weight, bone metabolism markers, and cellular health. Employing biomechanical analysis, micro-computed tomography (micro-CT), and transmission electron microscopy (TEM), we unearthed a reduction in body weight due to HT-2 toxin alone, with selenium deficiency exacerbating these effects synergistically. Our results unveil that both factors independently affect bone metabolism, yet their confluence leads to a pronounced degradation of bone health parameters, including alterations in calcium, phosphorus, and vitamin D levels, alongside marked changes in osteoblast and osteoclast activity and bone cell structures. The notable damage to femoral cortical and trabecular architectures underscores the perilous interplay between dietary selenium absence and HT-2 toxin presence, necessitating a deeper understanding of their separate and joint effects on bone integrity. These discoveries underscore the imperative for a nuanced approach to toxicology research and public health policy, highlighting the pivotal influence of environmental and nutritional factors on skeletal well-being.

BMP Signaling Is a Prognostic Marker in Patients With Colorectal Cancer and Associates With Frailty

Background/Aim

Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-β superfamily of ligands and have been shown to promote or suppress colorectal cancer (CRC) growth. Developing treatments that target BMPs is challenging due to their multiple roles, including involvement in the inflammatory response and nutritional status. The present study evaluated the prognostic value of BMP-4, which is believed to be highly expressed in CRC, and its correlation with inflammatory and nutrition statuses in patients with CRC.

Materials and Methods

We analyzed BMP-4 expression in tumor tissues from 144 patients who underwent CRC surgery using immunohistochemistry and evaluated the relationship between BMP-4 levels and clinical outcomes.

Results

Kaplan-Meier analysis revealed that patients with high expression levels of BMP-4 exhibited a shorter overall survival rate than those with low levels of expression. Multivariate analysis revealed that BMP-4 expression was an independent prognostic factor for overall survival and death from other diseases in CRC patients. Furthermore, high BMP-4 expression was significantly correlated with high C-reactive protein/Albumin ratio, sarcopenia, and osteopenia.

Conclusion

BMP-4 is a significant prognostic factor in CRC, particularly in predicting death from other diseases, while also showing associations with inflammatory and nutritional statuses.

Trematode Diplostomum pseudospathaceum inducing differential immune gene expression in sexual and gynogenetic gibel carp (Carassius gibelio): parasites facilitating the coexistence of two reproductive forms of the invasive species

Introduction

Parasite-mediated selection is considered one of the potential mechanisms contributing to the coexistence of asexual-sexual complexes. Gibel carp (Carassius gibelio), an invasive fish species in Europe, often forms populations composed of gynogenetic and sexual specimens.

Methods

The experimental infection was induced in gynogenetic and sexual gibel carp using eye-fluke Diplostomum pseudospathaceum (Trematoda), and the transcriptome profile of the spleen as a major immune organ in fish was analyzed to reveal the differentially expressed immunity-associated genes related to D. pseudospathaceum infection differing between gynogenetic and sexual gibel carp.

Results

High parasite infection was found in gynogenetic fish when compared to genetically diverse sexuals. Although metacercariae of D. pseudospathaceum are situated in an immune-privileged organ, our results show that eye trematodes may induce a host immune response. We found differential gene expression induced by eye-fluke infection, with various impacts on gynogenetic and sexual hosts, documenting for the majority of DEGs upregulation in sexuals, and downregulation in asexuals. Differences in gene regulation between gynogenetic and sexual gibel carp were evidenced in many immunity-associated genes. GO analyses revealed the importance of genes assigned to the GO terms: immune function, the Notch signaling pathway, MAP kinase tyrosine/threonine/phosphatase activity, and chemokine receptor activity. KEGG analyses revealed the importance of the genes involved in 12 immunity-associated pathways - specifically, FoxO signaling, adipocytokine signaling, TGF-beta signaling, apoptosis, Notch signaling, C-type lectin receptor signaling, efferocytosis, intestinal immune network for IgA production, insulin signaling, virion - human immunodeficiency virus, Toll-like receptor signaling, and phosphatidylinositol signaling system.

Discussion

Our study indicates the limited potential of asexual fish to cope with higher parasite infection (likely a loss of capacity to induce an effective immune response) and highlights the important role of molecular mechanisms associated with immunity for the coexistence of gynogenetic and sexual gibel carp, potentially contributing to its invasiveness.

Dysregulation of CD4+ and CD8+ resident memory T, myeloid, and stromal cells in steroid-experienced, checkpoint inhibitor colitis

BACKGROUND

Colitis caused by checkpoint inhibitors (CPI) is frequent and is treated with empiric steroids, but CPI colitis mechanisms in steroid-experienced or refractory disease are unclear.

METHODS

Using colon biopsies and blood from predominantly steroid-experienced CPI colitis patients, we performed multiplexed single-cell transcriptomics and proteomics to nominate contributing populations.

RESULTS

CPI colitis biopsies showed enrichment of CD4+resident memory (RM) T cells in addition to CD8+ RM and cytotoxic CD8+ T cells. Matching T cell receptor (TCR) clonotypes suggested that both RMs are progenitors that yield cytotoxic effectors. Activated, CD38+ HLA-DR+ CD4+ RM and cytotoxic CD8+ T cells were enriched in steroid-experienced and a validation data set of steroid-naïve CPI colitis, underscoring their pathogenic potential across steroid exposure. Distinct from ulcerative colitis, CPI colitis exhibited perturbed stromal metabolism (NAD+, tryptophan) impacting epithelial survival and inflammation. Endothelial cells in CPI colitis after anti-TNF and anti-cytotoxic T-lymphocyte-associated antigen 4 (anti-CTLA-4) upregulated the integrin α4β7 ligand molecular vascular addressin cell adhesion molecule 1 (MAdCAM-1), which may preferentially respond to vedolizumab (anti-α4β7).

CONCLUSIONS

These findings nominate CD4+ RM and MAdCAM-1+ endothelial cells for targeting in specific subsets of CPI colitis patients.

In Silico Gene Prioritization Highlights the Significance of Bone Morphogenetic Protein 4 (BMP4) Promoter Methylation across All Methylation Clusters in Colorectal Cancer

The cytosine-phosphate-guanine (CpG) island methylator phenotype (CIMP) represents one of the pathways involved in the development of colorectal cancer, characterized by genome-wide hypermethylation. To identify samples exhibiting hypermethylation, we used unsupervised hierarchical clustering on genome-wide methylation data. This clustering analysis revealed the presence of four distinct subtypes within the tumor samples, namely, CIMP-H, CIMP-L, cluster 3, and cluster 4. These subtypes demonstrated varying levels of methylation, categorized as high, intermediate, and very low. To gain further insights, we mapped significant probes from all clusters to Ensembl Regulatory build 89, with a specific focus on those located within promoter regions or bound regions. By intersecting the methylated promoter and bound regions across all methylation subtypes, we identified a total of 253 genes exhibiting aberrant methylation patterns in the promoter regions across all four subtypes of colorectal cancer. Among these genes, our comprehensive genome-wide analysis highlights bone morphogenic protein 4 (BMP4) as the most prominent candidate. This significant finding was derived through the utilization of various bioinformatics tools, emphasizing the potential role of BMP4 in colorectal cancer development and progression.