Arbutin Ameliorates Murine Colitis by Inhibiting JAK2 Signaling Pathway

2'-Hydroxycinnamaldehyde Alleviates Intestinal Inflammation by Attenuating Intestinal Mucosal Barrier Damage Via Directly Inhibiting STAT3

BACKGROUND

The currently available clinical therapeutic drugs for ulcerative colitis (UC) are considered inadequate owing to certain limitations. There have been reports on the anti-inflammatory effects of 2'-hydroxycinnamaldehyde (HCA). However, whether HCA can improve UC is still unclear. Here, we aimed to investigate the pharmacological effects of HCA on UC and its underlying molecular mechanisms.

METHODS

The pharmacological effects of HCA were comprehensively investigated in 2 experimental setups: mice with dextran sulfate sodium (DSS)-induced colitis and lipopolysaccharide (LPS)-treated fetal human colon (FHC) cells. Furthermore, the interaction between HCA and signal transducer and activator of transcription 3 (STAT3) was investigated using molecular docking. The FHC cells with STAT3 knockdown or overexpression and mice with intestinal epithelium-specific STAT3 deletion (STAT3ΔIEC) were used to evaluate whether STAT3 mediated the pharmacological effects of HCA.

RESULTS

2'-Hydroxycinnamaldehyde attenuated dysregulated expression of inflammatory cytokines in a dose-dependent manner while increasing the expression of tight junction proteins, reducing the apoptosis of intestinal epithelial cells, and effectively alleviating inflammation both in vivo and in vitro. 2'-Hydroxycinnamaldehyde bound directly to STAT3 and inhibited its activation. The modulation of STAT3 activation levels due to STAT3 knockdown or overexpression influenced the mitigating effects of HCA on colitis. Further analysis indicated that the remission effect of HCA was not observed in STAT3ΔIEC mice, indicating that STAT3 mediated the anti-inflammatory effects of HCA.

CONCLUSIONS

We present a novel finding that HCA reduces colitis severity by attenuating intestinal mucosal barrier damage via STAT3. This discovery holds promise as a potential new strategy to alleviate UC.

Targeting programmed cell death in inflammatory bowel disease through natural products: New insights from molecular mechanisms to targeted therapies

Inflammatory bowel disease (IBD) is an autoimmune disorder primarily characterized by intestinal inflammation and recurrent ulceration, leading to a compromised intestinal barrier and inflammatory infiltration. This disorder's pathogenesis is mainly attributed to extensive damage or death of intestinal epithelial cells, along with abnormal activation or impaired death regulation of immune cells and the release of various inflammatory factors, which contribute to the inflammatory environment in the intestines. Thus, maintaining intestinal homeostasis hinges on balancing the survival and functionality of various cell types. Programmed cell death (PCD) pathways, including apoptosis, pyroptosis, autophagy, ferroptosis, necroptosis, and neutrophil extracellular traps, are integral in the pathogenesis of IBD by mediating the death of intestinal epithelial and immune cells. Natural products derived from plants, fruits, and vegetables have shown potential in regulating PCD, offering preventive and therapeutic avenues for IBD. This article reviews the role of natural products in IBD treatment by focusing on targeting PCD pathways, opening new avenues for clinical IBD management.

Research advances of Zanthoxylum bungeanum Maxim. polyphenols in inflammatory diseases

Zanthoxylum bungeanum Maxim., commonly known as Chinese prickly ash, is a well-known spice and traditional Chinese medicine ingredient with a rich history of use in treating inflammatory conditions. This review provides a comprehensive overview of the botanical classification, traditional applications, and anti-inflammatory effects of Z. bungeanum, with a specific focus on its polyphenolic components. These polyphenols have exhibited considerable promise, as evidenced by preclinical studies in animal models, suggesting their therapeutic potential in human inflammatory diseases such as ulcerative colitis, arthritis, asthma, chronic obstructive pulmonary disease, cardiovascular disease, and neurodegenerative conditions. This positions them as a promising class of natural compounds with the potential to enhance human well-being. However, further research is necessary to fully elucidate their mechanisms of action and develop safe and effective therapeutic applications.

Association between inflammatory bowel disease and risk of stroke: a systematic review and meta-analysis of cohort studies

Background/objectives

Recently, four meta-analyses have explored the association between inflammatory bowel disease (IBD) and the risk of stroke. These studies have demonstrated that people with IBD may be at an increased risk of stroke. However, some limitations such as high heterogeneity and the lack of uniformity in the types of research, especially the reuse of some sample sizes, cannot be neglected. These factors reduce the credibility of their research conclusions. Therefore, we conducted a meta-analysis to explore this possible association.

Methods

PubMed, Embase, and Web of Science were searched from inception to 30 June 2023. A random effects model with the generic inverse variance method was used in this meta-analysis. The Review Manager software was used to obtain all relative risks (RRs) and their 95% confidence intervals (CIs). Publication bias was tested, and sensitivity and subgroup analyses were conducted to explore possible heterogeneities.

Results

This meta-analysis included 12 cohort studies (involving 4,495,055 individuals). Meta-analysis of these data has shown that IBD was associated with an increased risk of stroke (RR = 1.19, 95%CI:1.14-1.24, p < 0.00001). Our results were stable and robust in subgroup and sensitivity analyses.

Conclusions

Our results suggest that IBD is associated with an increased risk of stroke. To reduce the incidence of stroke, patients with IBD are encouraged to undergo stroke risk assessments, especially for young female patients; assessing the risk of ischemic stroke is of particular importance. Prospective studies considering stroke subtypes, IBD severity and treatments, regions, and other confounding factors are needed to further explore the nature of each association.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022373656.

Comparison of the anti-inflammatory effects of vitamin E and vitamin D on a rat model of dextran sulfate sodium-induced ulcerative colitis

The present study aimed to compare the clinical effects of vitamin E and vitamin D on a rat model of dextran sulfate sodium (DSS)-induced ulcerative colitis (UC), and to elucidate the underlying mechanisms associated with changes in the levels of cytokines. After successful establishment of the rat model of DSS-induced UC, prednisolone (1 mg/kg), vitamin D (50 ng) and vitamin E (6, 30 and 150 IU/kg) were orally administered for 1 week. The pharmacodynamics were evaluated by a daily combination of clinical observation (CO) scores, histopathological evaluations and assessment of molecular markers of inflammation. Administration of vitamin D, vitamin E (30 and 150 IU/kg), prednisolone, and the combination of vitamin D and vitamin E resulted in a decrease in CO scores. The severity of inflammation of the colon was markedly alleviated in the treatment groups compared with that in the untreated DSS group according to the results of histopathological examination; however, they showed different inhibitory effects on the levels of some cytokines. In conclusion, the present results indicated that oral administration of vitamin E could promote recovery of DSS-induced UC by the inhibition of proinflammatory cytokines, and that its underlying mechanism may differ from that of vitamin D and glucocorticoid drugs.

Exploring the Targets and Molecular Mechanisms of Thalidomide in the Treatment of Ulcerative Colitis: Network Pharmacology and Experimental Validation

BACKGROUND

Ulcerative colitis (UC) is a chronic, nonspecific, inflammatory disease of the intestine with an unknown cause. Thalidomide (THA) has been shown to be an effective drug for the treatment of UC. However, the molecular targets and mechanism of action of THA for the treatment of UC are not yet clear.

OBJECTIVES

Combining network pharmacology with in vitro experiments, this study aimed to investigate the potential targets and molecular mechanisms of THA for the treatment of UC.

METHODS

Firstly, relevant targets of THA against UC were obtained from public databases. Then, the top 10 hub targets and key molecular mechanisms of THA for UC were screened based on the network pharmacology approach and bioinformatics method. Finally, an in vitro cellular inflammation model was constructed using lipopolysaccharide (LPS) induced intestinal epithelial cells (NCM460) to validate the top 10 hub targets and key signaling pathways.

RESULTS

A total of 121 relevant targets of THA against UC were obtained, of which the top 10 hub targets were SRC, LCK, MAPK1, HSP90AA1, EGFR, HRAS, JAK2, RAC1, STAT1, and MAP2K1. The PI3K-Akt pathway was significantly associated with THA treatment of UC. In vitro experiments revealed that THA treatment reversed the expression of HSP90AA1, EGFR, STAT1, and JAK2 differential genes. THA was able to up- regulate the mRNA expression of pro-inflammatory factor IL-10 and decrease the mRNA levels of anti-inflammatory factors IL-6, IL-1β, and TNF-α. Furthermore, THA also exerted anti-inflammatory effects by inhibiting the activation of the PI3K/Akt pathway.

CONCLUSION

THA may play a therapeutic role in UC by inhibiting the PI3K-Akt pathway. HSP90AA1, EGFR, STAT1, and JAK2 may be the most relevant potential therapeutic targets for THA in the treatment of UC.

Hypoxic ASCs-derived Exosomes Attenuate Colitis by Regulating Macrophage Polarization via miR-216a-5p/HMGB1 Axis

BACKGROUND

Exosomes derived from mesenchymal stem cells have shown therapeutic effects for colitis. As a more clinically accessible resource, the therapeutic potential of exosomes from adipose-derived stem cells (ASCs) has not been fully elucidated, and whether hypoxia precondition could improve the therapeutic effect of ASC-derived exosomes in colitis remains elusive.

METHODS

In this study, exosomes were derived from ASCs under normoxia (NExos) and hypoxia (HExos) and were identified by detecting their morphology, size distribution, and exosome surface markers. The concentration of inflammation-related cytokines was detected by ELISA, and macrophage phenotype-related genes were determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), western blot, and immunofluorescence. A miRNA microarray sequencing analysis was conducted to confirm the differentially expressed miRNAs. Dextran sulfate sodium-induced colitis was employed as an in vivo assay.

RESULTS

Administration of NExos alleviated inflammation by modulating the balance of macrophages both in cellular assays and in vivo experiments, and HExos showed higher therapeutic efficiency than NExos. The miR-216a-5p in HExos was significantly enriched and promoted macrophage M2 polarization through transfer to macrophages by exosomes. The miR-216a-5p was confirmed to target the 3'-UTR of HMGB1. Mechanistically, hypoxia-induced ASCs release miR-216a-5p in an exosomal way that induced macrophage M2 polarization by regulating the HMGB1/TLR4/NF-κB signaling pathway.

CONCLUSIONS

Exosomal miR-216a-5p released from hypoxia-prime ASCs showed higher therapeutic efficiency than NExos in experimental colitis by promoting the M2 macrophage phenotype, which indicated that hypoxia prime may represent a promising approach to optimizing the function of ASC-derived exosomes.

Arbutin improves gut development and serum lipids via Lactobacillus intestinalis

Arbutin has been widely studied in whitening, anti-inflammatory, and antioxidant. However, the interaction between arbutin and intestinal microbes has been rarely studied. Thus, mice were treated with arbutin concentrations of 0, 0.1, 0.2, 0.4, and 1 mg/ml. We found that arbutin promoted gut development such as villus length, villus areas, and villus length/crypt depth (L/D). Total cholesterol (TC), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were significantly reduced by low concentrations of arbutin. Importantly, we analyzed the microbial composition in the control and 0.4 mg/ml arbutin group and found that the abundance of Lactobacillus intestinalis (L. intestinalis) was highest and enhanced in arbutin. Further, mice were fed with oral antibiotics and antibiotics + 0.4 mg/ml arbutin and then we transplanted fecal microbes from oral 0.4 mg/ml arbutin mice to mice pretreated with antibiotics. Our results showed that arbutin improves gut development, such as villus width, villus length, L/D, and villus areas. In addition, L. intestinalis monocolonization was carried out after a week of oral antibiotics and increased villus length, crypt depth, and villus areas. Finally, in vitro arbutin and L. intestinalis co-culture showed that arbutin promoted the growth and proliferation of L. intestinalis. Taken together, our results suggest that arbutin improves gut development and health of L. intestinalis. Future studies are needed to explore the function and mechanism of L. intestinalis affecting gut development.