Nanoparticles Carrying NF-κB p65-Specific siRNA Alleviate Colitis in Mice by Attenuating NF-κB-Related Protein Expression and Pro-Inflammatory Cellular Mediator Secretion

Oral Targeted Delivery of Codonopsis Radix Polysaccharide via Succinyl -DHA Functionalized Nanoparticles Efficiently Alleviates Ulcerative Colitis

Introduction

Ulcerative colitis (UC) is a chronic intestinal disease characterized by spleen-lung qi deficiency and dampness-pathogenic obstruction. Although there are various treatment options available, patients frequently encounter significant drug-related side effects. Previous studies have shown the potential of Codonopsis Radix polysaccharides A (CPA) in treating UC, but their limited bioavailability has restricted their clinical use. Therefore, the objective of this study was to develop a novel formulation that can address the aforementioned limitations and assess its potential advantages.

Methods and Results

We synthesized a negatively charged amphipathic prodrug called CPA-SA-DHA (CSD), which consists of CPA as the hydrophilic component, and succinic anhydride and docosahexaenoic acid as the hydrophobic segments. The CSD nanoparticles obtained had a particle size of 180.0 ± 3.2 nm, a negative zeta potential of -29.8 ± 5.3 mV, and a uniform shape with a PDI index of 0.230 ± 0.003. The interaction between positive and negative charges significantly increased the retention time of CSD nanoparticles in the colonic microenvironment. Furthermore, CSD nanoparticles demonstrated enhanced bioavailability in UC mice compared to CPA. Additionally, we observed that CSD nanoparticles exhibited therapeutic effects on DSS-induced UC mice by regulating the diversity and abundance of gut microbiota. This effect may be mediated by the inhibition of pro-inflammatory signaling pathways TLR4/NF-κB.

Conclusion

These findings confirm the potential of CSD nanoparticles as a promising treatment option for UC.

Recent advances on emerging nanomaterials for diagnosis and treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic idiopathic inflammatory disorder that affects the entire gastrointestinal tract and is associated with an increased risk of colorectal cancer. Mainstream clinical testing methods are time-consuming, painful for patients, and insufficiently sensitive to detect early symptoms. Currently, there is no definitive cure for IBD, and frequent doses of medications with potentially severe side effects may affect patient response. In recent years, nanomaterials have demonstrated considerable potential for IBD management due to their diverse structures, composition, and physical and chemical properties. In this review, we provide an overview of the advances in nanomaterial-based diagnosis and treatment of IBD in recent five years. Multi-functional bio-nano platforms, including contrast agents, near-infrared (NIR) fluorescent probes, and bioactive substance detection agents have been developed for IBD diagnosis. Based on a series of pathogenic characteristics of IBD, the therapeutic strategies of antioxidant, anti-inflammatory, and intestinal microbiome regulation of IBD based on nanomaterials are systematically introduced. Finally, the future challenges and prospects in this field are presented to facilitate the development of diagnosis and treatment of IBD.

RNAi therapies: Expanding applications for extrahepatic diseases and overcoming delivery challenges

The era of RNA medicine has become a reality with the success of messenger RNA (mRNA) vaccines against COVID-19 and the approval of several RNA interference (RNAi) agents in recent years. Particularly, therapeutics based on RNAi offer the promise of targeting intractable and previously undruggable disease genes. Recent advances have focused in developing delivery systems to enhance the poor cellular uptake and insufficient pharmacokinetic properties of RNAi therapeutics and thereby improve its efficacy and safety. However, such approach has been mainly achieved via lipid nanoparticles (LNPs) or chemical conjugation with N-Acetylgalactosamine (GalNAc), thus current RNAi therapy has been limited to liver diseases, most likely to encounter liver-targeting limitations. Hence, there is a huge unmet medical need for intense evolution of RNAi therapeutics delivery systems to target extrahepatic tissues and ultimately extend their indications for treating various intractable diseases. In this review, challenges of delivering RNAi therapeutics to tumors and major organs are discussed, as well as their transition to clinical trials. This review also highlights innovative and promising preclinical RNAi-based delivery platforms for the treatment of extrahepatic diseases.

Biomarkers of ulcerative colitis disease activity CXCL1, CYP2R1, LPCAT1, and NEU4 and their relationship to immune infiltrates

The diagnosis and assessment of ulcerative colitis (UC) poses significant challenges, which may result in inadequate treatment and a poor prognosis for patients. This study aims to identify potential activity biomarkers for UC and investigate the role of infiltrating immune cells in the disease. To perform gene set enrichment analysis, we utilized the cluster profiler and ggplot2 packages. Kyoto encyclopedia of genes and genomes was used to analyze degenerate enrichment genes. Significant gene set enrichment was determined using the cluster profiler and ggplot2 packages. Additionally, quantitative PCR (qRT-PCR) was employed to validate the expression of each marker in the ulcerative colitis model. We identified 651 differentially expressed genes (DEGs) and further investigated potential UC activity biomarkers. Our analysis revealed that CXCL1 (AUC = 0.710), CYP2R1 (AUC = 0.863), LPCAT1 (AUC = 0.783), and NEU4 (AUC = 0.833) were promising activity markers for the diagnosis of UC. Using rat DSS model, we validated these markers through qRT-PCR, which showed statistically significant differences between UC and normal colon mucosa. Infiltrating immune cell analysis indicated that M1 macrophages, M2 macrophages, activated dendritic cells (DCs), and neutrophils played crucial roles in the occurrence and progression of UC. Moreover, the activity markers exhibited varying degrees of correlation with activated memory CD4 T cells, M0 macrophages, T follicular helper cells, memory B cells, and activated DCs. The potential diagnostic genes for UC activity, such as CXCL1, CYP2R1, LPCAT1, and NEU4, as well as the infiltration of immune cells, may contribute to the pathogenesis and progression of UC.

A comprehensive review on RNA interference-mediated targeting of interleukins and its potential therapeutic implications in colon cancer

Colon cancer is the world's fourth leading cause of death. It is cancer of the latter part of the large intestine, i.e. the colon. Chronic inflammation over a long period also leads to the development of cancer. Cancer in the colon region is arduous to diagnose and is detected at a later stage when it metastasizes to other parts of the body like the liver, lungs, peritoneum, etc. Colon cancer is a great example of solid tumours associated with chronic inflammation. Although conventional therapies are effective, they lose their effectiveness beyond a certain point. Relapse of the disease occurs frequently. RNA interference (RNAi) is emerging as a great tool to specifically attack the cancer cells of a target site like the colon. RNAi deals with epigenetic changes made in the defective cells which ultimately leads to their death without harming the healthy cells. In this review, two types of epigenetic modulators have been considered, namely siRNA and miRNA, and their effect on interleukins. Interleukins, a class of cytokines, are major inflammatory responses of the body that are released by immune cells like leukocytes and macrophages. Some of these interleukins are pro-inflammatory, thereby promoting inflammation which eventually causes cancer. RNAi can prevent colon cancer by inhibiting pro-inflammatory interleukins.

Silencing of proinflammatory NF-κB and inhibition of herpes simplex virus (HSV) replication by ultrasmall gold nanoparticles (2 nm) conjugated with small-interfering RNA

Azide-terminated ultrasmall gold nanoparticles (2 nm gold core) were covalently functionalized with alkyne-terminated small-interfering siRNA duplexes by copper-catalyzed azide-alkyne cycloaddition (CuAAC; click chemistry). The nanoparticle core was visualized by transmission electron microscopy. The number of attached siRNA molecules per nanoparticle was determined by a combination of atomic absorption spectroscopy (AAS; for gold) and UV-Vis spectroscopy (for siRNA). Each nanoparticle carried between 6 and 10 siRNA duplex molecules which corresponds to a weight ratio of siRNA to gold of about 2.2 : 1. Different kinds of siRNA were conjugated to the nanoparticles, depending on the gene to be silenced. In general, the nanoparticles were readily taken up by cells and highly efficient in gene silencing, in contrast to free siRNA. This was demonstrated in HeLa-eGFP cells (silencing of eGFP) and in LPS-stimulated macrophages (silencing of NF-κB). Furthermore, we demonstrated that nanoparticles carrying antiviral siRNA potently inhibited the replication of Herpes simplex virus 2 (HSV-2) in vitro. This highlights the strong potential of siRNA-functionalized ultrasmall gold nanoparticles in a broad spectrum of applications, including gene silencing and treatment of viral infections, combined with a minimal dose of gold.

Uptake of Functional Ultrasmall Gold Nanoparticles in 3D Gut Cell Models

Ultrasmall gold nanoparticles (2 nm) easily penetrate the membranes of intestinal murine epithelial cells (MODE-K) and colorectal cancer cells (CT-26). They are also taken up by 3D spheroids (400 µm) of these cell types and primary gut organoids (500 µm). In contrast, dissolved dyes are not taken up by any of these cells or 3D structures. The distribution of fluorescent ultrasmall gold nanoparticles inside cells, spheroids, and gut organoids is examined by confocal laser scanning microscopy. Nanoparticles conjugated with the cytostatic drug doxorubicin and a fluorescent dye exhibit significantly greater cytotoxicity toward CT-26 tumor spheroids than equally concentrated dissolved doxorubicin, probably because they enter the interior of a spheroid much more easily than dissolved doxorubicin. Comprehensive analyses show that the cellular uptake of ultrasmall gold nanoparticles occurs by different endocytosis pathways.

siRNA-based nanotherapeutics as emerging modalities for immune-mediated diseases: A preliminary review

Immune‐mediated diseases (IMDs) are chronic conditions that have an immune‐mediated etiology. Clinically, these diseases appear to be unrelated, but pathogenic pathways have been shown to connect them. While inflammation is a common occurrence in the body, it may either stimulate a favorable immune response to protect against harmful signals or cause illness by damaging cells and tissues. Nanomedicine has tremendous promise for regulating inflammation and treating IMIDs. Various nanoparticles coated with nanotherapeutics have been recently fabricated for effective targeted delivery to inflammatory tissues. RNA interference (RNAi) offers a tremendous genetic approach, particularly if traditional treatments are ineffective against IMDs. In cells, several signaling pathways can be suppressed by using RNAi, which blocks the expression of particular messenger RNAs. Using this molecular approach, the undesirable effects of anti‐inflammatory medications can be reduced. Still, there are many problems with using short‐interfering RNAs (siRNAs) to treat IMDs, including poor localization of the siRNAs in target tissues, unstable gene expression, and quick removal from the blood. Nanotherapeutics have been widely used in designing siRNA‐based carriers because of the restricted therapy options for IMIDs. In this review, we have discussed recent trends in the fabrication of siRNA nanodelivery systems, including lipid‐based siRNA nanocarriers, liposomes, and cationic lipids, stable nucleic acid‐lipid particles, polymeric‐based siRNA nanocarriers, polyethylenimine (PEI)‐based nanosystems, chitosan‐based nanoformulations, inorganic material‐based siRNA nanocarriers, and hybrid‐based delivery systems. We have also introduced novel siRNA‐based nanocarriers to control IMIDs, such as pulmonary inflammation, psoriasis, inflammatory bowel disease, ulcerative colitis, rheumatoid arthritis, etc. This study will pave the way for new avenues of research into the diagnosis and treatment of IMDs.