Fluorescent Labeling and Imaging of IL-22 mRNA-Loaded Lipid Nanoparticles.

Lipid nanoparticle (LNP)-based drug delivery systems (DDSs) are widely recognized for their ability to enhance efficient and precise delivery of therapeutic agents, including nucleic acids like DNA and mRNA. Despite this acknowledgment, there is a notable knowledge gap regarding the systemic biodistribution and organ accumulation of these nanoparticles. The ability to track LNPs in vivo is crucial for understanding their fate within biological systems. Fluorescent labeling of LNPs facilitates real-time tracking, quantification, and visualization of their behavior within biological systems, providing valuable insights into biodistribution, cellular uptake, and the optimization of drug delivery strategies. Our prior research established reversely engineered LNPs as an exceptional mRNA delivery platform for treating ulcerative colitis. This study presents a detailed protocol for labeling interleukin-22 (IL-22) mRNA-loaded LNPs, their oral administration to mice, and visualization of DiR-labeled LNPs biodistribution in the gastrointestinal tract using IVIS spectrum. This fluorescence-based approach will assist researchers in gaining a dynamic understanding of nanoparticle fate in other models of interest. Key features • This protocol is developed to assess the delivery of IL-22 mRNA to ulcerative colitis sites using lipid nanoparticles. • This protocol uses fluorescent DiR dye for imaging of IL-22 mRNA-loaded lipid nanoparticles in the gastrointestinal tract of mice. • This protocol employs the IVIS spectrum for imaging.

Unleashing the Potential of Oral Deliverable Nanomedicine in the Treatment of Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD), marked by chronic gastrointestinal tract inflammation, poses a significant global medical challenge. Current treatments for IBD, including corticosteroids, immunomodulators, and biologics, often require frequent systemic administration through parenteral delivery, leading to nonspecific drug distribution, suboptimal therapeutic outcomes, and adverse effects. There is a pressing need for a targeted drug delivery system to enhance drug efficacy and minimize its systemic impact. Nanotechnology emerges as a transformative solution, enabling precise oral drug delivery to inflamed intestinal tissues, reducing off-target effects, and enhancing therapeutic efficiency. The advantages include heightened bioavailability, sustained drug release, and improved cellular uptake. Additionally, the nano-based approach allows for the integration of theranostic elements, enabling simultaneous diagnosis and treatment. Recent preclinical advances in oral IBD treatments, particularly with nanoformulations such as functionalized polymeric and lipid nanoparticles, demonstrate remarkable cell-targeting ability and biosafety, promising to overcome the limitations of conventional therapies. These developments signify a paradigm shift toward personalized and effective oral IBD management. This review explores the potential of oral nanomedicine to enhance IBD treatment significantly, focusing specifically on cell-targeting oral drug delivery system for potential use in IBD management. We also examine emerging technologies such as theranostic nanoparticles and artificial intelligence, identifying avenues for the practical translation of nanomedicines into clinical applications.

Immunofluorescent Staining Assay of 3D Cell Culture of Colonoids Isolated from Mice Colon.

Here, we describe immunofluorescent (IF) staining assay of 3D cell culture colonoids isolated from mice colon as described previously. Primary cultures developed from isolated colonic stem cells are called colonoids. Immunofluorescence can be used to analyze the distribution of proteins, glycans, and small molecules-both biological and non-biological ones. Four-day-old colonoid cell cultures grown on Lab-Tek 8-well plate are fixed by paraformaldehyde. Fixed colonoids are then subjected to antigen retrieval and blocking followed by incubation with primary antibody. A corresponding secondary antibody tagged with desired fluorescence is used to visualize primary antibody-marked protein. Counter staining to stain actin filaments and nucleus to assess cell structure and DNA in nucleus is performed by choosing the other two contrasting fluorescences. IF staining of colonoids can be utilized to visualize molecular markers of cell behavior. This technique can be used for translation research by isolating colonoids from colitis patients' colons, monitoring the biomarkers, and customizing their treatments. Key features • Analysis of molecular markers of cell behavior. • Protocol to visualize proteins in 3D cell culture. • This protocol requires colonoids isolated from mice colon grown on matrigel support. • Protocol requires at least eight days to complete.

Unveiling Colitis: A Journey through the Dextran Sodium Sulfate-induced Model.

Animal models of inflammatory bowel disease (IBD) are valuable tools for investigating the factors involved in IBD pathogenesis and evaluating new therapeutic options. The dextran sodium sulfate (DSS)-induced model of colitis is arguably the most widely used animal model for studying the pathogenesis of and potential treatments for ulcerative colitis (UC), which is a primary form of IBD. This model offers several advantages as a research tool: it is highly reproducible, relatively easy to generate and maintain, and mimics many critical features of human IBD. Recently, it has also been used to study the role of gut microbiota in the development and progression of IBD and to investigate the effects of other factors, such as diet and genetics, on colitis severity. However, although DSS-induced colitis is the most popular and flexible model for preclinical IBD research, it is not an exact replica of human colitis, and some results obtained from this model cannot be directly applied to humans. This review aims to comprehensively discuss different factors that may be involved in the pathogenesis of DSS-induced colitis and the issues that should be considered when using this model for translational purposes.

This review discusses different factors that may be involved in the pathogenesis of DSS-induced colitis and the issues that should be considered when using this model for translational purposes.

Prevention of Colitis-Associated Cancer via Oral Administration of M13-Loaded Lipid Nanoparticles.

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease, is known to increase the risk of colitis-associated cancer (CAC). CAC has been found to be unresponsive to standard chemotherapy regimens, and the current treatments do not utilize effective small-molecule drugs and colon-targeted delivery systems. Previous studies indicated that the M13-nano-liposome (NL) formulation can effectively target the colon and reshape the gut microbiota in ex vivo cultures, generating altered microbial metabolites that can efficiently prevent chronic UC. In this study, we tested the cancer cell uptake ability of the NL formulation and investigated the potential of the M13-NL formulation to prevent CAC in the azoxymethane (AOM)-exposed IL10-/- mouse model. Our findings demonstrate that oral administration of M13-NL prevents tumor development in AOM-exposed IL10-/- mice, suggesting that M13-NL is a promising oral drug formulation for preventing CAC.

Oral administration of M13-loaded nanoliposomes is safe and effective to treat colitis-associated cancer in mice.

OBJECTIVE: Colitis-associated cancer (CAC) treatment lacks effective small-molecule drugs and efficient targeted delivery systems. Here, we loaded M13 (an anti-cancer drug candidate) to colon-targeting ginger-derived nanoliposomes (NL) and investigated if orally administered M13-NL could enhance the anticancer effects of M13 in CAC mouse models. METHODS: The biopharmaceutical properties of M13 were assessed by physicochemical characterizations. The in vitro immunotoxicity of M13 was assessed against PBMCs using FACS and the mutagenic potential of M13 was evaluated by the Ames assay. The in vitro efficacy of M13 was tested in 2D- and 3D-cultured cancerous intestinal cells. AOM/DSS-induced CAC mice were used to evaluate the therapeutic effects of free M13 or M13-NL on CAC in vivo. RESULTS: M13 has beneficial physiochemical properties, including high stability, and no apparent immunotoxicity or mutagenic potential in vitro. M13 is effective against the growth of 2D- and 3D-cultured cancerous intestinal cells in vitro. The in vivo safety and efficacy of M13 were significantly improved by using NL for drug delivery (p < 0.001). Oral administration of M13-NL exhibited excellent therapeutic effects in AOM/DSS-induced CAC mice. CONCLUSION: M13-NL is a promising oral drug formulation for CAC treatment.

Challenges to Safe Nanomedicine Treatment.

Nanotechnology has the potential to revolutionize the field of drug treatment by enabling the targeted delivery and controlled release of drugs at a cellular level [...].

Preparation and Characterization of IL-22 mRNA-loaded Lipid Nanoparticles.

Interleukin-22 (IL-22) has been demonstrated as a critical regulator of epithelial homeostasis and repair; it showed an anti-inflammatory effect against ulcerative colitis. Local microinjection of IL-22 cDNA vector has been shown to be effective in treating ulcerative colitis in mouse models. However, microinjection comes with multiple technical challenges for routine colon-targeted drug delivery. In contrast, oral administration can get around these challenges and provide comparable efficacy. We showed in previous studies that oral administration of new lipid nanoparticles (nLNP)-encapsulated IL-22 mRNA targets the colon region and efficiently ameliorates colitis. This protocol describes the details of preparing and characterizing the nLNP-encapsulated IL-22 mRNA using three major lipids that mimic the natural ginger-derived nanoparticles. It provides an nLNP platform that can be used to orally deliver other types of nucleic acids to the colon.

Palladium encapsulated mesoporous silica nanoparticles for the rapid detection of analytes.

We designed a simple, inexpensive, and user-friendly assay using mesoporous silica nanoparticles to detect analytes. Highly stable and uniform palladium nanoparticles covered with mesoporous silica (Pd@mSiO2) were generated and characterized extensively using physical methods. Human Serum Albumin (HSA) protein or ssDNA specific to the HIV gag region was capped onto the Pd@mSiO2 electrostatically. This "cap" prevented the Pd(0) inside the mesoporous silica nanoparticles from catalyzing the conversion of non-fluorescent molecules to fluorescent molecules. In the presence of target anti-HSA antibodies or complementary sequence (HIV gag), HSA protein or DNA cap dissociated from the surface of Pd@mSiO2-NH2 through the specific antigen-antibody reaction or DNA hybridization, allowing Pd(0) to convert the non-fluorescent molecules to fluorescent molecules. The limit and range of detection of anti-HSA antibodies were 3.8 nM and 3.8 nM to 133.3 nM, respectively. The limit and range of detection of HIV gag were 1.6 nM and 1.6 nM to 15 nM, respectively. This simple, inexpensive, "add sample and measure" diagnostic assay could potentially be incorporated into point of care diagnostics for low-resource settings.

SARS-CoV-2 Induces Epithelial-Enteric Neuronal Crosstalk Stimulating VIP Release.

BACKGROUND: Diarrhea is present in up to 30-50% of patients with COVID-19. The mechanism of SARS-CoV-2-induced diarrhea remains unclear. We hypothesized that enterocyte-enteric neuron interactions were important in SARS-CoV-2-induced diarrhea. SARS-CoV-2 induces endoplasmic reticulum (ER) stress in enterocytes causing the release of damage associated molecular patterns (DAMPs). The DAMPs then stimulate the release of enteric neurotransmitters that disrupt gut electrolyte homeostasis. METHODS: Primary mouse enteric neurons (EN) were exposed to a conditioned medium from ACE2-expressing Caco-2 colonic epithelial cells infected with SARS-CoV-2 or treated with tunicamycin (ER stress inducer). Vasoactive intestinal peptides (VIP) expression and secretion by EN were assessed by RT-PCR and ELISA, respectively. Membrane expression of NHE3 was determined by surface biotinylation. RESULTS: SARS-CoV-2 infection led to increased expression of BiP/GRP78, a marker and key regulator for ER stress in Caco-2 cells. Infected cells secreted the DAMP protein, heat shock protein 70 (HSP70), into the culture media, as revealed by proteomic and Western analyses. The expression of VIP mRNA in EN was up-regulated after treatment with a conditioned medium of SARS-CoV-2-infected Caco-2 cells. CD91, a receptor for HSP70, is abundantly expressed in the cultured mouse EN. Tunicamycin, an inducer of ER stress, also induced the release of HSP70 and Xbp1s, mimicking SARS-CoV-2 infection. Co-treatment of Caco-2 with tunicamycin (apical) and VIP (basolateral) induced a synergistic decrease in membrane expression of Na+/H+ exchanger (NHE3), an important transporter that mediates intestinal Na+/fluid absorption. CONCLUSIONS: Our findings demonstrate that SARS-CoV-2 enterocyte infection leads to ER stress and the release of DAMPs that up-regulates the expression and release of VIP by EN. VIP in turn inhibits fluid absorption through the downregulation of brush-border membrane expression of NHE3 in enterocytes. These data highlight the role of epithelial-enteric neuronal crosstalk in COVID-19-related diarrhea.

Glial cell derived neurotrophic factor prevents western diet and palmitate-induced hepatocyte oxidative damage and death through SIRT3.

Nonalcoholic fatty liver disease (NAFLD) is associated with increased oxidative stress that leads to hepatocyte and mitochondrial damage. In this study we investigated the mechanisms involved in the induction of oxidative stress and impairment of mitochondrial quality control and mitophagy in hepatocytes by the saturated fatty acid palmitate and Western diet feeding in mice and if their harmful effects could be reversed by the neurotrophic factor glial cell derived neurotrophic factor (GDNF). Western diet (WD)-feeding increased hepatic lipid peroxidation in control mice and, in vitro palmitate induced oxidative stress and impaired the mitophagic clearance of damaged mitochondria in hepatocytes. This was accompanied by reductions in hepatocyte sirtuin 3 (SIRT3) deacetylase activity, gene expression and protein levels as well as in superoxide dismutase enzyme activity. These reductions were reversed in the liver of Western diet fed GDNF transgenic mice and in hepatocytes exposed to palmitate in the presence of GDNF. We demonstrate an important role for Western diet and palmitate in inducing oxidative stress and impairing mitophagy in hepatocytes and an ability of GDNF to prevent this. These findings suggest that GDNF or its agonists may be a potential therapy for the prevention or treatment of NAFLD.

Oral delivery of IL-22 mRNA-loaded lipid nanoparticles targeting the injured intestinal mucosa: A novel therapeutic solution to treat ulcerative colitis.

Oral mRNA delivery is a promising yet understudied approach for treating inflammatory bowel disease (IBD). Inspired by the colon-targeting ability of ginger-derived nanoparticles (GDNPs), we reversely engineered lipid nanoparticles that comprise the three major lipids identified in GDNPs. When mixed at the ratio found in GDNPs, the selected lipids (phosphatidic acid, monogalactosyldiacylglycerol, and digalactosyldiacylglycerol; 5:2:3) self-assembled into new lipid nanoparticles (nLNPs) in phosphate-buffered saline. We encapsulated IL-22-mRNA within the nLNPs, as enhanced IL-22 expression in the colon is known to have potent anti-inflammatory efficacy against ulcerative colitis (UC). The IL-22 mRNA-loaded nLNPs (IL-22/nLNPs) were found to be about 200 nm in diameter and have a zeta potential of -18 mV. Oral delivery of IL-22/nLNPs elevated the protein expression level of IL-22 in the colonic mucosa of mice. In a mouse model of acute colitis, mice fed with IL-22/nLNPs experienced an accelerated healing process, as indicated by the recovery of more body weight and colon length as well as reduction of the histological index, colonic MPO activity, fecal lipocalin concentration, and mRNA expression levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß). Our results suggest that our reversely engineered nLNPs is an excellent mRNA delivery platform for treating ulcerative colitis.

The Current Status of Molecular Biomarkers for Inflammatory Bowel Disease.

Diagnosis and prognosis of inflammatory bowel disease (IBD)-a chronic inflammation that affects the gastrointestinal tract of patients-are challenging, as most clinical symptoms are not specific to IBD, and are often seen in other inflammatory diseases, such as intestinal infections, drug-induced colitis, and monogenic diseases. To date, there is no gold-standard test for monitoring IBD. Endoscopy and imaging are essential diagnostic tools that provide information about the disease's state, location, and severity. However, the invasive nature and high cost of endoscopy make it unsuitable for frequent monitoring of disease activity in IBD patients, and even when it is possible to replace endoscopy with imaging, high cost remains a concern. Laboratory testing of blood or feces has the advantage of being non-invasive, rapid, cost-effective, and standardizable. Although the specificity and accuracy of laboratory testing alone need to be improved, it is increasingly used to monitor disease activity or to diagnose suspected IBD cases in combination with endoscopy and/or imaging. The literature survey indicates a dearth of summarization of biomarkers for IBD testing. This review introduces currently available non-invasive biomarkers of clinical importance in laboratory testing for IBD, and discusses the trends and challenges in the IBD biomarker studies.

Prevention of Ulcerative Colitis by Autologous Metabolite Transfer from Colitogenic Microbiota Treated with Lipid Nanoparticles Encapsulating an Anti-Inflammatory Drug Candidate.

Modulating the gut microbiota composition is a potent approach to treat various chronic diseases, including obesity, metabolic syndrome, and ulcerative colitis (UC). However, the current methods, such as fecal microbiota transplantation, carry a risk of serious infections due to the transmission of multi-drug-resistant organisms. Here, we developed an organism-free strategy in which the gut microbiota is modulated ex vivo and microbiota-secreted metabolites are transferred back to the host. Using feces collected from the interleukin-10 (IL-10) knockout mouse model of chronic UC, we found that a drug candidate (M13)-loaded natural-lipid nanoparticle (M13/nLNP) modified the composition of the ex vivo-cultured inflamed gut microbiota and its secreted metabolites. Principal coordinate analysis (PCoA) showed that M13/nLNP shifted the inflamed microbiota composition toward the non-inflamed direction. This compositional modification induced significant changes in the chemical profiles of secreted metabolites, which proved to be anti-inflammatory against in vitro-cultured NF-κß reporter cells. Further, when these metabolites were orally administered to mice, they established strong protection against the formation of chronic inflammation. Our study demonstrates that ex vivo modulation of microbiota using M13/nLNP effectively reshaped the microbial secreted metabolites and that oral transfer of these metabolites might be an effective and safe therapeutic approach for preventing chronic UC.

Preparation, Characterization, and Cell Uptake of PLGA/PLA-PEG-FA Nanoparticles.

Oral administration of colon-targeting nanoformulations holds many advantages over the systemic delivery of free drugs, or traditional nontargeting formulations in the treatment of ulcerative colitis (UC). Currently, the most conventional method for constructing colon-targeting drug delivery systems (DDS) is by integrating the biocompatible materials poly(lactic-co-glycolic acid) (PLGA) and polylactic acid (PLA) into a copolymer. This PLGA/PLA-polyethylene glycol-folic acid (PEG-FA) copolymeric nanoformulation effectively delivers the drugs for uptake by various human colon cancer cells (e.g., HT-29 and HCT-116) and mouse colon cancer cells (CT-26). There is, however, a distinct lack of comprehensive protocols for the construction of such copolymer. This protocol details an easy-to-follow single-step method for the construction of a colon-targeting PLGA/PLA-PEG-FA nanoformulation, which encapsulates a fluorescent dye and demonstrates the visualization of its cell uptake in vitro.

Inflammatory bowel disease biomarkers.

Inflammatory bowel disease (IBD) is characterized as chronic inflammation in the gastrointestinal tract, which includes two main subtypes, Crohn's disease and ulcerative colitis. Endoscopy combined with biopsy is the most effective way to establish IBD diagnosis and disease management. Imaging techniques have also been developed to monitor IBD. Although effective, the methods are expensive and invasive, which leads to pain and discomfort. Alternative noninvasive biomarkers are being explored as tools for IBD prognosis and disease management. This review focuses on novel biomarkers that have emerged in recent years. These serological biomarkers and microRNAs could potentially be used for disease management in IBD, thereby decreasing patient discomfort and morbidity.

Infrared spectrometric biomarkers for ulcerative colitis screening using human serum samples.

This study uses infrared spectrometry coupled with data analysis techniques to understand colitis-induced alterations in the molecular components of serum samples. Using samples from 18 ulcerative colitis patients and 28 healthy volunteers, we assessed features such as absorbance values at wavenumbers of 1033 and 1076 cm-1 , and the ratios at 1121 versus 1020 cm-1 and 1629 versus 1737 cm-1 . Through the deconvolution of the amide I band, protein secondary structure analysis was performed. Colitis-induced alterations are reflected as fluctuations in the vibrational modes, and are used to identify associated spectral signatures. The results of the study show statistically significant differences in five identifying spectral signatures. Among them, the sensitivity and specificity of the spectral signature, I1121 /I1020 , were 100% and 86%, respectively. These findings resemble our earlier proof-of-concept investigations in mouse models and provide preliminary evidence that this could be a reliable diagnostic test for human patients.

Orally Administered Natural Lipid Nanoparticle-Loaded 6-Shogaol Shapes the Anti-Inflammatory Microbiota and Metabolome.

The past decade has seen increasing interest in microbiota-targeting therapeutic strategies that aim to modulate the gut microbiota's composition and/or function to treat chronic diseases, such as inflammatory bowel disease (IBD), metabolic symptoms, and obesity. While targeting the gut microbiota is an innovative means for treating IBD, it typically requires an extended treatment time, hampering its potential application. Herein, using an established natural-lipid nanoparticle (nLNP) platform, we demonstrate that nLNPs encapsulated with the drug candidate 6-shogaol (6S/nLNP) distinctly altered microbiota composition within one day of treatment, significantly accelerating a process that usually requires five days using free 6-shogaol (6S). In addition, the change in the composition of the microbiota induced by five-day treatment with 6S/nLNP was maintained for at least 15 days (from day five to day 20). The consequent alteration in the fecal metabolic profile stemming from this compositional change manifested as functional changes that enhanced the in vitro anti-inflammatory and wound-healing efficacy of macrophage cells (Raw 264.7) and epithelial cells (Caco-2 BBE1), respectively. Further, this metabolic compositional change, as reflected in an altered metabolic profile, promoted a robust anti-inflammatory effect in a DSS-induced mouse model of acute colitis. Our study demonstrates that, by near-instantly modulating microbiota composition and function, an nLNP-based drug-delivery platform might be a powerful tool for treating ulcerative colitis.