Cholesterol sulfate alleviates ulcerative colitis by promoting cholesterol biosynthesis in colonic epithelial cells

Integrative bioinformatics approach yields a novel gene expression risk model for prognosis and progression prediction in prostate cancer

Prostate cancer (PCa), a prevalent malignancy among elderly males, exhibits a notable rate of advancement, even when subjected to conventional androgen deprivation therapy or chemotherapy. An effective progression prediction model would prove invaluable in identifying patients with a higher progression risk. Using bioinformatics strategies, we integrated diverse data sets of PCa to construct a novel risk model predicated on gene expression and progression-free survival (PFS). The accuracy of the model was assessed through validation using an independent data set. Eight genes were discerned as independent prognostic factors and included in the prediction model. Patients assigned to the high-risk cohort demonstrated a diminished PFS, and the areas under the curve of our model in the validation set for 1-year, 3-year, and 5-year PFS were 0.9325, 0.9041 and 0.9070, respectively. Additionally, through the application of single-cell RNA sequencing to two castration-related prostate cancer (CRPC) samples and two hormone-related prostate cancer (HSPC) samples, we discovered that luminal cells within CRPC exhibited an elevated risk score. Subsequent molecular biology experiments corroborated our findings, illustrating heightened SYK expression levels within tumour tissues and its contribution to cancer cell migration. We found that the knockdown of SYK could inhibit migration in PCa cells. Our progression-related risk model demonstrated the potential prognostic value of SYK and indicated its potential as a target for future diagnosis and treatment strategies in PCa management.

Ultrasonic-assisted extraction of polysaccharide from Paeoniae Radix alba: Extraction optimization, structural characterization and antioxidant mechanism in vitro

Paeoniae Radix alba is used in Traditional Chinese Medicine for the treatment of gastrointestinal disorders, immunomodulatory, cancer, and other diseases. In the current study, the yield of Paeoniae Radix alba polysaccharide (PRP) was significantly increased with optimal ultrasound-assisted extraction compared to hot water extraction. Further, an acidic polysaccharide (PRP-AP) was isolated from PRP after chromatographic separation and was characterized as a typical pectic polysaccharide with side chains of arabinogalactans types I and II. Moreover, it showed antioxidant effects on LPS-induced damage on IPEC-J2 cells determined by qRT-PCR and ELISA, including decreasing the pro-inflammatory factors' expressions and increasing the antioxidant enzymes activities, which was shown to be related to the Nrf2/Keap1 pathway modulated by PRP-AP. The metabolites change (such as itaconate, cholesterol sulfate, etc.) detected by untargeted metabolomic analysis in cells was also shown to be modulated by PRP-AP, and these metabolites were further utilized and protected cells damaged by LPS. These results revealed the cellular active mechanism of the macromolecular PRP-AP on protecting cells, and supported the hypothesis that PRP-AP has strong benefits as an alternative dietary supplement for the prevention of intestinal oxidative stress by modulating cellular metabolism.

Bioinspired and biomimetic strategies for inflammatory bowel disease therapy

Inflammatory bowel disease (IBD) is an idiopathic chronic inflammatory bowel disease with high morbidity and an increased risk of cancer or death, resulting in a heavy societal medical burden. While current treatment modalities have been successful in achieving long-term remission and reducing the risk of complications, IBD remains incurable. Nanomedicine has the potential to address the high toxic side effects and low efficacy in IBD treatment. However, synthesized nanomedicines typically exhibit some degree of immune rejection, off-target effects, and a poor ability to cross biological barriers, limiting the development of clinical applications. The emergence of bionic materials and bionic technologies has reshaped the landscape in novel pharmaceutical fields. Biomimetic drug-delivery systems can effectively improve biocompatibility and reduce immunogenicity. Some bioinspired strategies can mimic specific components, targets or immune mechanisms in pathological processes to produce targeting effects for precise disease control. This article highlights recent research on bioinspired and biomimetic strategies for the treatment of IBD and discusses the challenges and future directions in the field to advance the treatment of IBD.

Revisiting the effect of cholesteryl sulfate on clotting and fibrinolysis: Inhibition of human thrombin and other human blood proteases

Cholesteryl sulfate (CS) was quantitatively synthesized by microwave-assisted sulfonation of cholesterol followed by sodium exchange chromatography. In vitro effects of CS on human thrombin and other serine proteases of the coagulation and fibrinolysis processes were investigated using a series of biochemical and biophysical techniques. CS was found to inhibit thrombin with an IC50 value of 140.8 ± 21.8 μM at pH 7.4 and 25 ○C. Michaelis-Menten kinetics indicated that thrombin inhibition by CS is non-competitive (allosteric) in nature. Fluorescence-based binding studies indicated that CS binds to thrombin with a KD value of 180.9 ± 18.9 μM. Given the lack of competition with heparins and a hirudin peptide in competitive inhibition assays, it appears that CS does not bind to thrombin's exosites 1 or 2 and it rather recognizes a different allosteric exosite. CS was found to partially inhibit thrombin-mediated fibrinogen activation with an IC50 value of 175.5 ± 17.5 μM and efficacy of ∼26.0 ± 6.6%. Likewise, CS selectively doubled the activated partial thromboplastin time with EC2x of 521 μM. Interestingly, CS was found to also inhibit factors Xa and XIa as well as plasmin with IC50 values of ∼85-250 μM and efficacy of 94-100%. Nevertheless, CS most potently inhibited factor XIIa with an IC50 Value of ∼17 μM and efficacy of 60%. Surprisingly, CS did not inhibit factor IXa. These results encourage further in vitro and in vivo investigation of CS to better understand its (patho-) physiological roles in coagulation and hemostasis.

Fecal transplantation of young mouse donors effectively improves enterotoxicity in elderly recipients exposed to triphenyltin

Triphenyltin (TPT) is a widely used biocide known for its high toxicity to various organisms, including humans, and its potential contribution to environmental pollution. The aging process leads to progressive deterioration of physiological functions in the elderly, making them more susceptible to the toxic effects of environmental pollutants. This study aimed to investigate the mitigating effect of fecal transplantation in young mice on the toxicological impairment caused by TPT exposure. For the study, 18-month-old mice were divided into four groups with six replicates each. The control group was fed a basal diet, the TPT group was exposed to 3.75 mg/Kg TPT, the feces group received fecal transplantation from 8-week-old young mice, and the combined group was exposed to 3.75 mg/Kg TPT after receiving fecal transplantation. Compared with the elderly control group, TPT induced significant upregulation of mRNA expression of pro-inflammatory factors (IL-1β, IL-6, TNF-α), while the anti-inflammatory factor gene IL-10 was significantly suppressed. The mRNA expression of intestinal barrier proteins (Claudin, Occludin, Muc2) was also significantly downregulated. However, fecal transplantation in young mice alleviated TPT-induced changes in inflammatory factors, ameliorated oxidative stress, and increased the activities of antioxidant enzymes (including SOD, CAT, GSH-Px). Further analysis using 16 s RNA showed that exposure to TPT led to changes in the composition of the intestinal flora. Untargeted metabolomics observations of feces from older mice revealed that exposure to TPT resulted in altered fecal metabolites. Fecal transplantation in young mice altered the microbiota of TPT-exposed older mice, especially by enhancing the levels of core probiotics. Similar beneficial effects were observed through untargeted metabolomics. Overall, this study highlights the potential benefits of young fecal transplantation in protecting the elderly from the toxicity of TPT, offering a promising approach to improve healthy aging.

Spatial Transcriptomic and Metabolomic Landscapes of Oral Submucous Fibrosis-Derived Oral Squamous Cell Carcinoma and its Tumor Microenvironment

In South and Southeast Asia, the habit of chewing betel nuts is prevalent, which leads to oral submucous fibrosis (OSF). OSF is a well-established precancerous lesion, and a portion of OSF cases eventually progress to oral squamous cell carcinoma (OSCC). However, the specific molecular mechanisms underlying the malignant transformation of OSCC from OSF are poorly understood. In this study, the leading-edge techniques of Spatial Transcriptomics (ST) and Spatial Metabolomics (SM) are integrated to obtain spatial location information of cancer cells, fibroblasts, and immune cells, as well as the transcriptomic and metabolomic landscapes in OSF-derived OSCC tissues. This work reveals for the first time that some OSF-derived OSCC cells undergo partial epithelial-mesenchymal transition (pEMT) within the in situ carcinoma (ISC) region, eventually acquiring fibroblast-like phenotypes and participating in collagen deposition. Complex interactions among epithelial cells, fibroblasts, and immune cells in the tumor microenvironment are demonstrated. Most importantly, significant metabolic reprogramming in OSF-derived OSCC, including abnormal polyamine metabolism, potentially playing a pivotal role in promoting tumorigenesis and immune evasion is discovered. The ST and SM data in this study shed new light on deciphering the mechanisms of OSF-derived OSCC. The work also offers invaluable clues for the prevention and treatment of OSCC.

The adverse impacts of ammonia stress on the homeostasis of intestinal health in Pacific white shrimp (Litopenaeus vannamei)

Ammonia is a prevalent pollutant in aquaculture systems that poses a risk to shrimp health. The shrimp's intestine plays a crucial role in immunity and metabolism. Therefore, we exposed Litopenaeus vannamei to 2 mg/L ammonia-N stress for a duration of 7 days, and explored the alterations in intestinal tissue morphology, physiological status, microbial community, and metabolic function. The findings revealed that ammonia stress led to a decrease in shrimp survival rates and inflicted damage to the intestinal mucosa, resulting in epithelial exfoliation. The mRNA relative expression levels of oxidative stress genes (Nrf2 and SOD) were elevated, while the level of GPx was decreased. Additionally, there was an increase in the levels of endoplasmic reticulum stress genes (Bip, IRE1 and XBP1), inflammatory cytokines (NF-κB and JNK), and apoptosis mediators (CytC and Casp-3) were increased. Ammonia stress also caused a decline in intestinal microbial diversity and significant variations in the bacterial community composition, including Bacteroides, Enterococcus, Faecalibacterium, Nautella, Pseudoalteromonas, Tenacibaculum, and Weissella. Furthermore, ammonia stress disrupted the intestinal metabolic function, particularly affecting pyrimidine, purine, amino acid, and alkaloid metabolism. These results revealed that 2 mg/L ammonia-N stress damaged the intestinal health of the shrimp by damaging mucosal integrity, affecting physiological homeostasis, causing microbial community and metabolic variation, which are related to the decreased survival of the shrimp and should be paid attention to in shrimp farming.

Interactions between dietary cholesterol and intestinal flora and their effects on host health

The interactions between dietary cholesterol and intestinal microbiota strongly affect host health. In recent years, relevant studies have greatly advanced this field and need to be summarized to deepen the understanding of dietary cholesterol-intestinal microbiota interactions and their effects on host health. This review covers the most recent frontiers on the effects of dietary cholesterol on the intestinal microbiota and its metabolites, the metabolism of cholesterol by the intestinal microbiota, and the effects of the interactions on host health. Several animal-feeding studies reported that dietary cholesterol altered different intestinal microbiota in the body, while mainly causing alterations in intestinal microbial metabolites such as bile acids, short-chain fatty acids, and tryptophan derivatives. Alterations in these metabolites may be a novel mechanism mediating cholesterol-related diseases. The cholesterol microbial metabolite, coprostanol, has a low absorption rate and is excreted in the feces. Thus, microbial conversion of cholesterol-to-coprostanol may be an important way of cholesterol-lowering by the organism. Cholesterol-3-sulfate is a recently discovered microbial metabolite of cholesterol, mainly metabolized by Bacteroides containing the Bt_0416 gene. Its effects on host health have been preliminarily characterized and are mainly related to immune modulation and repair of the intestinal epithelium.

Prolactin inhibitor changes testosterone production, testicular morphology, and related genes expression in cashmere goats

Prolactin has multifaceted roles in lactation, growth, metabolism, osmoregulation, behavior, and the reproduction of animals. This study aimed to investigate the involvement of prolactin in testicular function in cashmere goats. Twenty cashmere goats were randomly assigned to either the control group (CON) or the bromocriptine treatment group (BCR, bromocriptine, prolactin inhibitor). Blood and testis samples collected for analysis after 30 days of treatment. The results indicated that, compared with the CON group, BCR significantly decreased (p < 0.05) the serum concentrations of prolactin, and significantly increased (p < 0.05) the levels of testosterone and luteinizing hormone (LH) on day 30. The serum level of the follicle-stimulating hormone (FSH) was not affected (p > 0.05) by the treatment. The mean seminiferous tubule diameter and spermatogenic epithelium thickness were increased (p < 0.05) in the BCR group. Subsequently, we performed RNA sequencing and bioinformatics analysis to identify the key genes and pathways associated with the regulation of spermatogenesis or testosterone secretion function. A total of 142 differentially expressed genes (DEGs) were identified (91 were upregulated, 51 were downregulated). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that the DEGs were mainly involved in the extracellular matrix (ECM), hippo, and steroid hormone biosynthesis, which are related to testicular function. The expression of the genes SULT2B1, CYP3A24, and CYP3A74 in the steroid hormone biosynthesis pathway significantly increased (p < 0.05) in the BCR group, which was validated by qRT-PCR. These results provide a basis for understanding the mechanisms underlying the regulation of testicular function by prolactin in cashmere goats.

Mume Fructus (Prunus mume Sieb. et Zucc.) extract accelerates colonic mucosal healing of mice with colitis induced by dextran sulfate sodium through potentiation of cPLA2-mediated lysophosphatidylcholine synthesis

BACKGROUND

Mume Fructus (MF) is the fruit of Prunus mume Sieb. et Zucc, a plant of Rosaceae family. Previous studies demonstrated that MF was capable of ameliorating ulcerative colitis (UC) in mice, its action mechanism needs to be clarified.

PURPOSE

This study deciphered whether and how MF extract accelerates colonic mucosal healing, the therapeutic endpoint of UC.

METHODS

Biochemical, histopathological and qRT-PCR analyses were utilized to define the therapeutic efficacy of MF on dextran sulfate sodium (DSS)-induced colitis in mice. UHPLC-QTOF-MS/MS-based metabolomics technique was adopted to explore the changes of endogenous metabolites associated with UC and responses to MF intervention. qRT-PCR analysis was performed to confirm the molecular pathway in vivo. The effects of MF and lysophosphatidylcholine (LPC) on cell viability, wound healing, proliferation, and migration were examined through a series of in vitro experiments. Moreover, the effects of different subtypes of phospholipase A2 (PLA2) inhibitors on MF-treated colonic epithelial cells were detected by wound healing test and transwell assay.

RESULTS

Orally administered MF could alleviate colitis in mice mainly by accelerating the healing of colonic mucosa. Guided by an unbiased metabolomics screen, we identified LPC synthesis as a major modifying pathway in colitis mice after MF treatment. Notably, MF facilitated the synthesis of LPC by enhancing the expression of PLA2 in colitis mice. Mechanistically, MF and LPC accelerated wound closure by promoting cell migration. Moreover, the promotion of MF on wound healing and migration of colonic epithelial cells was blunted by a cytosolic phospholipase A2 (cPLA2) inhibitor.

CONCLUSION

MF can facilitate colonic mucosal healing of mice with colitis through cPLA2-mediated intestinal LPC synthesis, which may become a novel therapeutic agent of UC.

Single-cell RNA sequencing reveals that HSD17B2 in cancer-associated fibroblasts promotes the development and progression of castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) responds poorly to existing therapy and appears as the lethal consequence of prostate cancer (PCa) progression. The tumour microenvironment (TME) has been thought to play a crucial role in CRPC progression. Here, we conducted single-cell RNA sequencing analysis on two CRPC and two hormone-sensitive prostate cancer (HSPC) samples to reveal potential leading roles in castration resistance. We described the single-cell transcriptional landscape of PCa. Higher cancer heterogeneity was explored in CRPC, with stronger cell cycling status and heavier copy number variant burden of luminal cells. Cancer-associated fibroblasts (CAFs), which are one of the most critical components of TME, demonstrated unique expression and cell-cell communication features in CRPC. A CAFs subtype with high expression of HSD17B2 in CRPC was identified with inflammatory features. HSD17B2 catalyses the conversion of testosterone and dihydrotestosterone to their less active forms, which was associated with steroid hormone metabolism in PCa tumour cells. However, the characteristics of HSD17B2 in PCa fibroblasts remained unknown. We found that HSD17B2 knockdown in CRPC-CAFs could inhibit migration, invasion, and castration resistance of PCa cells in vitro. Further study showed that HSD17B2 could regulate CAFs functions and promote PCa migration through the AR/ITGBL1 axis. Overall, our study revealed the important role of CAFs in the formation of CRPC. HSD17B2 in CAFs regulated AR activation and subsequent ITGBL1 secretion to promote the malignant behaviour of PCa cells. HSD17B2 in CAFs could serve as a promising therapeutic target for CRPC.

Propensity score analysis the clinical characteristics of active distal and extensive ulcerative colitis: a retrospective study

Background and Objectives: Ulcerative Colitis (UC) subtypes defined by disease extent and shared pathophysiology are important. Analyzing the clinical characteristics of UC with different disease extent and optimizing clinical typing are conducive to the pathogenesis research, disease monitoring and precise treatment. Methods: 188 patients with active UC were divided into distal and extensive colitis. The clinical characteristics of the two groups were analyzed by propensity score. Spearman is used for correlation analysis, and receiver operating characteristic (ROC) curve was used to evaluate the ability of clinical indicators to predict Mayo endoscopic subscore (MES). Results: Compared with distal colitis, extensive colitis had more severe disease activity, younger age, higher utilization rate of corticosteroids and incidence of extra intestinal manifestations (EIMs), and clinical indicators were differentially expressed in the two groups. After using propensity score, the incidence of EIMs in the extensive colitis was still higher than that in distal colitis. Inflammation, coagulation and immune indicators like CRP, FC, IL-10, D-D and α1-MG are higher in extensive colitis, and metabolic indicators like LDL-C, HDL-C, TC, GSP and albumin are higher in distal colitis. The correlation between clinical indicators and MES is affected by disease extent. The area under curve (AUC) of CRP + D-D + α2-MG for predicting distal colitis MES3 was 0.85, and the AUC of IL-6+ GSP+ α1-MG predicted extensive colitis MES3 can reach 0.82. Conclusion: Differential clinical indicators can become potential markers for predicting disease progression and prognosis, and have significance for UC mechanism research and drug development. We can select biomarkers according to lesion site.

Causal Effects of Blood Lipid Traits on Inflammatory Bowel Diseases: A Mendelian Randomization Study

Inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis (UC), have become a global health problem with a rapid growth of incidence in newly industrialized countries. Observational studies have recognized associations between blood lipid traits and IBDs, but the causality still remains unclear. To determine the causal effects of blood lipid traits, including triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) on IBDs, two-sample Mendelian randomization (MR) analyses were conducted using the summary-level genome-wide association study (GWAS) statistics of blood lipid traits and IBDs. Our univariable MR using multiplicative random-effect inverse-variance weight (IVW) method identified TC (OR: 0.674; 95% CI: 0.554, 0.820; p < 0.00625) and LDL-C (OR: 0.685; 95% CI: 0.546, 0.858; p < 0.00625) as protective factors of UC. The result of our multivariable MR analysis further provided suggestive evidence of the protective effect of TC on UC risk (OR: 0.147; 95% CI: 0.025, 0.883; p < 0.05). Finally, our MR-BMA analysis prioritized TG (MIP: 0.336; θ^_MACE: -0.025; PP: 0.31; θ^_λ: -0.072) and HDL-C (MIP: 0.254; θ^_MACE: -0.011; PP: 0.232; θ^_λ: -0.04) for CD and TC (MIP: 0.721; θ^_MACE: -0.257; PP: 0.648; θ^_λ: -0.356) and LDL-C (MIP: 0.31; θ^_MACE: -0.095; PP: 0.256; θ^_λ: -0.344) for UC as the top-ranked protective factors. In conclusion, the causal effect of TC for UC prevention was robust across all of our MR approaches, which provide the first evidence that genetically determined TC is causally associated with reduced risk of UC. The finding of this study provides important insights into the metabolic regulation of IBDs and potential metabolites targeting strategies for IBDs intervention.

Cholesterol sulfate limits neutrophil recruitment and gut inflammation during mucosal injury

During mucosal injury, intestinal immune cells play a crucial role in eliminating invading bacteria. However, as the excessive accumulation of immune cells promotes inflammation and delays tissue repair, it is essential to identify the mechanism that limits the infiltration of immune cells to the mucosal-luminal interface. Cholesterol sulfate (CS) is the lipid product of the sulfotransferase SULT2B1 and suppresses immune reactions by inhibiting DOCK2-mediated Rac activation. In this study, we aimed to elucidate the physiological role of CS in the intestinal tract. We found that, in the small intestine and colon, CS is predominantly produced in the epithelial cells close to the lumen. While dextran sodium sulfate (DSS)-induced colitis was exacerbated in Sult2b1-deficient mice with increased prevalence of neutrophils, the elimination of either neutrophils or intestinal bacteria in Sult2b1-deficient mice attenuated disease development. Similar results were obtained when the Dock2 was genetically deleted in Sult2b1-deficient mice. In addition, we also show that indomethacin-induced ulcer formation in the small intestine was exacerbated in Sult2b1-deficient mice and was ameliorated by CS administration. Thus, our results uncover that CS acts on inflammatory neutrophils, and prevents excessive gut inflammation by inhibiting the Rac activator DOCK2. The administration of CS may be a novel therapeutic strategy for inflammatory bowel disease and non-steroidal anti-inflammatory drug-induced ulcers.

β-hydroxybutyrate inhibits ferroptosis-mediated pancreatic damage in acute liver failure through the increase of H3K9bhb

Acute pancreatitis and hyperamylasemia are often seen in patients with acute liver failure (ALF). However, the underlying mechanisms remain elusive. This study describes pancreatic tissue damage and exocrine dysfunction in a mouse model of major-liver-resection-induced ALF. The analysis of 1,264 clinical cases of liver failure (LF) showed that the incidence of hyperamylasemia and hyperlipasemia in patients with LF is 5.5% and 20%, respectively. Metabolomic studies indicate that glutathione (GSH)-deficiency-caused ferroptosis contributes to pancreatic damage in mouse ALF. β-hydroxybutyrate (β-HB) is the only metabolite downregulated in the liver, serum, and pancreas. Our data suggest that β-HB protects pancreatic cells and tissues from GSH-deficiency-caused ferroptosis. β-HB administration in ALF mice restores the expression of ferroptosis-suppressor genes through histone H3 lysine 9 β-hydroxybutyrylation (H3K9bhb)-mediated chromatin opening. Our findings highlight β-HB as an endogenous metabolite regulating ferroptosis in the pancreas and extend our understanding of the pathophysiology of ALF-induced pancreatitis.

The role of cholesterol and mitochondrial bioenergetics in activation of the inflammasome in IBD

Inflammatory Bowel Disease (IBD) is characterized by a loss of intestinal barrier function caused by an aberrant interaction between the immune response and the gut microbiota. In IBD, imbalance in cholesterol homeostasis and mitochondrial bioenergetics have been identified as essential events for activating the inflammasome-mediated response. Mitochondrial alterations, such as reduced respiratory complex activities and reduced production of tricarboxylic acid (TCA) cycle intermediates (e.g., citric acid, fumarate, isocitric acid, malate, pyruvate, and succinate) have been described in in vitro and clinical studies. Under inflammatory conditions, mitochondrial architecture in intestinal epithelial cells is dysmorphic, with cristae destruction and high dynamin-related protein 1 (DRP1)-dependent fission. Likewise, these alterations in mitochondrial morphology and bioenergetics promote metabolic shifts towards glycolysis and down-regulation of antioxidant Nuclear erythroid 2-related factor 2 (Nrf2)/Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) signaling. Although the mechanisms underlying the mitochondrial dysfunction during mucosal inflammation are not fully understood at present, metabolic intermediates and cholesterol may act as signals activating the NLRP3 inflammasome in IBD. Notably, dietary phytochemicals exhibit protective effects against cholesterol imbalance and mitochondrial function alterations to maintain gastrointestinal mucosal renewal in vitro and in vivo conditions. Here, we discuss the role of cholesterol and mitochondrial metabolism in IBD, highlighting the therapeutic potential of dietary phytochemicals, restoring intestinal metabolism and function.