Application of Polymeric Nano-Materials in Management of Inflammatory Bowel Disease

Alginate-based drug carrier systems to target inflammatory bowel disease: A review

Inflammatory bowel disease (IBD) is an inflammatory disorder that affects the gastrointestinal tract. IBD has become an increasingly common condition in both developed and developing nations over the last few decades, owing to a variety of factors like a rising population and diets packed with processed and junk foods. While the root pathophysiology of IBD is unknown, treatments are focused on medications aimed to mitigate symptoms. Alginate (AG), a marine-derived polysaccharide, is extensively studied for its biocompatibility, pH sensitivity, and crosslinking nature. This polymer is thoroughly researched in drug delivery systems for IBD treatment, as it is naturally available, non-toxic, cost effective, and can be easily and safely cross-linked with other polymers to form an interconnected network, which helps in controlling the release of drugs over an extended period. There are various types of drug delivery systems developed from AG to deliver therapeutic agents; among them, nanotechnology-based systems and hydrogels are popular due to their ability to facilitate targeted drug delivery, reduce dosage, and increase the therapeutic efficiency. AG-based carrier systems are not only used for the sustained release of drug, but also used in the delivery of siRNA, interleukins, and stem cells for site directed drug delivery and tissue regenerating ability respectively. This review is focussed on pathogenesis and currently studied medications for IBD, AG-based drug delivery systems and their properties for the alleviation of IBD. Moreover, future challenges are also be discoursed to improve the research of AG in the field of biopharmaceuticals and drug delivery.

Therapeutic effect of biosynthetic gold nanoparticles on multidrug-resistant Escherichia coli and Salmonella species isolated from ruminants

Background and Aim:

Multidrug-resistant (MDR) pathogenic microorganisms have become a global problem in ruminants as a result of the intensive use of antibiotics, causing the development of resistance among gut microbiota. The antibiotic-resistant microorganisms can be transferred from diseased animals to humans. This study aimed to determine the prevalence of MDR Escherichia coli and Salmonella spp. isolated from cattle, buffaloes, sheep, and goats suffering from respiratory signs, diarrhea, and mastitis and to screen the antibiotic sensitivity of selected isolated bacteria. It also detected antibiotic-resistance genes by polymerase chain reaction (PCR), produced green gold nanoparticles (AuNPs) using plant extracts (Artemisia herba-alba and Morus alba), and evaluated the antimicrobial activities of these biosynthesized nanoparticles on selected pathogens (E. coli and Salmonella spp.).

Materials and Methods:

MDR E. coli and Salmonella spp. were investigated using fecal samples (n=408), nasal swabs (n=358), and milk samples (n=227) of cattle, buffaloes, sheep, and goats with or without clinical signs, including respiratory manifestations, pneumonia, diarrhea, and mastitis, from different governorates in Egypt. E. coli and Salmonella spp. were isolated and identified on selective media, which were confirmed by biochemical reactions and PCR. Antimicrobial susceptibility testing against 10 commonly used antibiotics was performed using the Kirby-Bauer disk diffusion method. Antibiotic resistance genes bla_TEM, bla_SHV, bla_OXA, and bla_CTX−M were detected by PCR. The antibacterial effect of the biosynthesized AuNPs was evaluated by MIC and well diffusion assay. The biosynthesized AuNPs were also characterized by ultraviolet-visible spectrophotometry and transmission electron microscopy (TEM).

Results:

Among all fecal samples, the prevalence of E. coli was 18.4% (183/993) and that of Salmonella spp. was 16.7% (66/408), as determined by cultural and molecular tests. All isolates of E. coli and Salmonella spp. were 100% resistant to ampicillin (AM) and amoxicillin and highly resistant to cefoxitin and AM-sulbactam. The total rate of resistance genes in E. coli was 61.2% (112/183), while that in Salmonella was 63.6% (42/66) for pathogens isolated from ruminants with respiratory manifestations, pneumonia, diarrhea, and mastitis. Among the resistance genes, bla_TEM had the highest prevalence rate in E. coli (25.9%, 21/81) while bla_SHV had the lowest (9.8%, 8/81) in fecal swabs. AuNPs were successfully synthesized using aqueous leaf extract of A. herba-alba and M. alba as bioreducing agents. TEM analysis showed particle size of 10-42 nm for A. herba-alba and M. alba AuNPs. The biosynthesized AuNPs showed antibacterial activity against MDR E. coli and Salmonella spp.

Conclusion:

Rapid and accurate diagnostic methods are the cornerstone for effective treatment to reduce the risk of antimicrobial-resistant pathogenic microorganisms. This is particularly important for overcoming the increasing rate of MDR in ruminants with respiratory manifestations, pneumonia, diarrhea, and mastitis. This can be complemented by the development of AuNPs synthesized in an environmentally friendly manner AuNPs using natural plant extracts for the treatment of antibiotic-resistant microorganisms.

Organoid Technology: A Reliable Developmental Biology Tool for Organ-Specific Nanotoxicity Evaluation

Engineered nanomaterials are bestowed with certain inherent physicochemical properties unlike their parent materials, rendering them suitable for the multifaceted needs of state-of-the-art biomedical, and pharmaceutical applications. The log-phase development of nano-science along with improved "bench to beside" conversion carries an enhanced probability of human exposure with numerous nanoparticles. Thus, toxicity assessment of these novel nanoscale materials holds a key to ensuring the safety aspects or else the global biome will certainly face a debacle. The toxicity may span from health hazards due to direct exposure to indirect means through food chain contamination or environmental pollution, even causing genotoxicity. Multiple ways of nanotoxicity evaluation include several in vitro and in vivo methods, with in vitro methods occupying the bulk of the "experimental space." The underlying reason may be multiple, but ethical constraints in in vivo animal experiments are a significant one. Two-dimensional (2D) monoculture is undoubtedly the most exploited in vitro method providing advantages in terms of cost-effectiveness, high throughput, and reproducibility. However, it often fails to mimic a tissue or organ which possesses a defined three-dimensional structure (3D) along with intercellular communication machinery. Instead, microtissues such as spheroids or organoids having a precise 3D architecture and proximate in vivo tissue-like behavior can provide a more realistic evaluation than 2D monocultures. Recent developments in microfluidics and bioreactor-based organoid synthesis have eased the difficulties to prosper nano-toxicological analysis in organoid models surpassing the obstacle of ethical issues. The present review will enlighten applications of organoids in nanotoxicological evaluation, their advantages, and prospects toward securing commonplace nano-interventions.

Nanotechnology in Colorectal Cancer for Precision Diagnosis and Therapy

Colorectal cancer (CRC) is the third most frequently occurring tumor in the human population. CRCs are usually adenocarcinomatous and originate as a polyp on the inner wall of the colon or rectum which may become malignant in the due course of time. Although the therapeutic options of CRC are limited, the early diagnosis of CRC may play an important role in preventive and therapeutic interventions to decrease the mortality rate. The CRC-affected tissues exhibit several molecular markers that may be exploited as the novel strategy to develop newer approaches for the treatment of the disease. Nanotechnology consists of a wide array of innovative and astonishing nanomaterials with both diagnostics and therapeutic potential. Several nanomaterials and nano formulations such as Carbon nanotubes, Dendrimer, Liposomes, Silica Nanoparticles, Gold nanoparticles, Metal-organic frameworks, Core-shell polymeric nano-formulations, Nano-emulsion System, etc can be used to targeted anticancer drug delivery and diagnostic purposes in CRC. The light-sensitive photosensitizer drugs loaded gold and silica nanoparticles can be used to diagnose as well as the killing of CRC cells by the targeted delivery of anticancer drugs to cancer cells. This review is focused on the recent advancement of nanotechnology in the diagnosis and treatment of CRC.

Current Strategies and Potential Prospects of Nanomedicine-Mediated Therapy in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) such as Crohn's disease and ulcerative colitis are highly debilitating. IBDs are associated with the imbalance of inflammatory mediators within the inflamed bowel. Conventional drugs for IBD treatment include anti-inflammatory medications and immune suppressants. However, they suffer from a lack of bioavailability and high dose-induced systemic side effects. Nanoparticle (NP)-derived therapy improves therapeutic efficacy and increases targeting specificity. Recent studies have shown that nanomedicines, based on bowel disease's pathophysiology, are a fast-growing field. NPs can prolong the circulation period and reduce side effects by improving drug encapsulation and targeted delivery. Here, this review summarizes various IBD therapies with a focus on NP-derived applications, whereas their challenges and future perspectives have also been discussed.