Challenges in the local delivery of peptides and proteins for oral mucositis management

Development of a Novel Histatin-5 Mucoadhesive Gel for the Treatment of Oral Mucositis: In Vitro Characterization and In Vivo Evaluation

Antimicrobial peptides have appeared to be promising candidates for therapeutic purposes due to their broad antimicrobial activity and non-toxicity. Histatin-5 (Hst-5) is a notable salivary antimicrobial peptide that exhibited therapeutic properties in the oral cavity. Oral mucositis is an acute inflammation of the oral cavity, following cancer therapy. The current treatment methods of oral mucositis have low effectiveness. The aim of this study was to design, formulate and characterize a mucoadhesive gel delivery system for Hst-5 usage in the treatment of oral mucositis. Carbopol 934 and hydroxypropyl methylcellulose (HPMC) have been used in the development of a Hst-5 mucoadhesive gel that was optimized by using Box-Behnken design. The optimized formulation was evaluated in-vitro, based on mucoadhesive strength, viscoelasticity, spreadability, release rate, peptide secondary structure analysis, antimicrobial activity, and storage stability. The efficacy of Hst-5 gel was assessed in vivo in a chemotherapy-induced mucositis model. The results showed a sustained release of Hst-5 from the new formulation. Hst-5 gel exerted antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The histopathological, immunohistochemical and statistical analysis showed that the Hst-5 gel had wound healing activity in vivo. The findings of this study indicate that the mentioned compound possesses promising potential as a novel and efficient therapeutic agent in managing oral mucositis. Moreover, the results suggest that the compound is commercially feasible for further development and utilization.

Association of MTHFR and ABCB1 polymorphisms with MTX-induced mucositis in Chinese paediatric patients with acute lymphoblastic leukaemia, lymphoma or osteosarcoma-A retrospective cohort study

WHAT IS KNOWN AND OBJECTIVE

MTX pharmacology and toxicity involve several metabolizing enzymes and transporters whose functions have been suggested to be altered by genetic polymorphisms. The current study is to investigate the relationship between the genetic variation and MTX-induced adverse drug effects.

METHODS

A total of 80 paediatric patients (aged 1-14 years) were enrolled in this study. Toxicity was assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0 scoring system. Genotyping was performed by MassARRAY Assay method. Data were analysed using Spss statistical package version 17.0 and Plink v1.07 software. The HWE was tested by a chi-square test. The Fisher's exact test (chi-squaretest) was used to compare the distributions of genotypes between cases and controls. OR and 95%CI were applied to evaluate the association of genetic variants with the presence of mucositis using unconditional logistic regression.

RESULTS AND DISCUSSION

Mucosal inflammatory injuries were found in 28 children. SNPs of rs1128503 (p = 0.0022, OR = 3.04, 95%CI = 1.39-6.64) and rs1045642 (p = 0.0052, OR = 2.38, 95%CI = 1.15-5.00) located in the gene of ABCB1 and SNPs of rs1801133 (p = 0.040, OR = 2.50, 95%CI = 1.06-5.88) located in the gene of MTHFR show marked impacts on the risk of developing mucositis.

WHAT IS NEW AND CONCLUSION

SNPs of ABCB1 rs1128503, rs1045642 and MTHFR rs1801133 can be risk predictor for MTX-induced mucositis in Chinese paediatric patients diagnosed with acute lymphoblastic leukaemia, lymphoma or osteosarcoma.

Fabrication of oral nanovesicle in-situ gel based on Epigallocatechin gallate phospholipid complex: Application in dental anti-caries

The conventional anti-caries agents exhibit many shortcomings such as poor stability, low efficacy or short residence time in the oral environment, it is urgent to develop efficacy treatments to prevent dental caries. As the most active polyphenols from tea, Epigallocatechin gallate (EGCG) shows remarkable anti-cariogenic bioactivity. However, the poor stability and low bioavailability of EGCG limit its potential application. This study aimed to fabricate nanovesicles in-situ gel based on EGCG phospholipid complex in order to increase its stability and efficacy. The formation of EGCG phospholipid complex was characterized by Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The ethanol injection method was used to prepare the EGCG-loaded nanovesicles, an optimal ratio of Poloxamer407 (P407) and Poloxamer188 (P188) as in-situ gel matrix was selected to fabricate oral nanovesicles in-situ gel. EGCG-loaded nanovesicle in-situ gel based on the phospholipid complex had uniform spherical shape without any agglomeration. The discrete nanoparticle with a size (131.44 ± 4.24 nm) and a negative zeta potential value at -30.7 ± 0.5 mV possessed good physical stability and high entrapment efficiency (83.66 ± 3.2%). The formulation exhibited a strong antibacterial activity on S. mutans, which could reduce acid production and tooth surface adhesion. In addition, EGCG formulation could inhibit the formation of glucan and biofilm from S. mutans by suppressing the activity of glycosyltransferase enzymes (GTF). In conclusion, the EGCG-loaded nanovesicle in-situ gel holds great promise as an efficient anti-cariogenic formulation for topical oral delivery.

Oral peptide delivery: challenges and the way ahead

Peptides and proteins have emerged as potential therapeutic agents and, in the search for the best treatment regimen, the oral route has been extensively evaluated because of its non-invasive and safe nature. The physicochemical properties of peptides and proteins along with the hurdles in the gastrointestinal tract (GIT), such as degrading enzymes and permeation barriers, are challenges to their delivery. To address these challenges, several conventional and novel approaches, such as nanocarriers, site-specific and stimuli specific delivery, are being used. In this review, we discuss the challenges to the oral delivery of peptides and the approaches used to tackle these challenges.

Oromucosal precursors of in loco hydrogels for wound-dressing and drug delivery in oral mucositis: Retain, resist, and release

Oromucosal films and tablets were developed as multifunctional biomaterials for the treatment of oral mucositis. These are intended to function as a hybrid, performing as a controlled drug delivery system and as a wound-dressing device. The dosage forms are precursors for in loco hydrogels that are activated by the saliva. An anti-inflammatory and anesthetic activity is attained from budesonide tripartite polymeric nanoparticles and lidocaine, while the polymeric network allows the protection and cicatrization of the wound. Different biomaterials and blends were investigated, focusing on the capacity to retain and resist on-site, as well as achieve a long-lasting controlled release. As the limiting factor, the choice was made according to the films' results. A polymer mix of Methocel™ K100M and Carbopol® (974P, EDT 2020, or Ultrez 10) blends were used. Overall, regrading critical factors, Carbopol® increased films' elasticity and flexibility, mucoadhesion, and the strength of the hydrogels, while higher concentrations led to thicker, more opaque, and lower strain resistance products. Whereas 974P and Ultrez 10 performed similarly, EDT 2020 led to uniformity problems and weaker films, hydrogels and bioadhesion. The optimized products were enhanced with sodium hyaluronate and drug-loaded for further characterization. Concerning the dosage form, the films' hydrogels were more resilient, while the tablets had higher mucoadhesiveness and longer swelling. Although through different networks and mechanisms, both dosage forms and grades revealed similar release profiles. A Case II time-evolving stereoselectivity for the 22R and 22S budesonide epimers was found, and Fickian-diffusion for lidocaine. Ultimately, the developed formulations show great potential to be used in OM management. Both of the selected grades at 0.6% displayed excellent performance, while Ultrez 10 can be preferable for the films' production due to its lower viscosity before neutralization and higher after activation. Where the tablets are easier to produce and offer better adhesion, the films are more customizable post-production and have higher rheological performance for wound-dressing.

Swellable polymeric particles for the local delivery of budesonide in oral mucositis

Topical drug delivery in the oral mucosa has its set of challenges due to the unique anatomical and physiological features of the oral cavity. As such, the outcomes of local pharmacological treatments in oral disorders can fail due to unsuccessfully drug delivery. Oral mucositis, a severe inflammatory and ulcerative side effect of oncological treatments, is one of such diseases. Although the damaged tissue is within reach, no approved topical drug treatment is available. Several strategies based on its physiopathology have been implemented and clinically used. Even so, results tend to lack or be insufficient to improve patient's quality of life. The use of corticosteroids has been employed in such strategies due to their strong anti-inflammatory action. Typically, these are administrated in simple liquid formulations, where the drug is dispersed or solubilized, lacking the ability to maintain local concentration. In this work, we propose the development of a biocompatible delivery system with boosted abilities of retention and control release of budesonide, a corticosteroid with an elevated ratio of topical anti-inflammatory to systemic action. Through spray-drying, polymeric particles of Chitosan and Eudragit® E PO were produced and characterized for the vectorization of this drug.

A Delivery System for Oral Administration of Proteins/Peptides Through Bile Acid Transport Channels

Proteins and peptides are poorly absorbed via oral administration because of the gastrointestinal tract environment and lysosomal digestion after apical endocytosis. A delivery system, consisting of a deoxycholic acid-conjugated nanometer-sized carrier, may enhance the absorption of proteins in the intestine via the bile acid pathway. Deoxycholic acid is first conjugated to chitosan. Liposomes are then prepared and loaded with the model drug insulin. Finally, the conjugates are bound to the liposome surface to form deoxycholic acid and chitosan conjugate-modified liposomes (DC-LIPs). This study demonstrates that DC-LIPs can promote the intestinal absorption of insulin via the apical sodium-dependent bile acid transporter, based on observing fluorescently stained tissue slices of the rat small intestine and a Caco-2 cell uptake experiment. Images of intestinal slices revealed that excellent absorption of DC-LIPs is achieved via apical sodium-dependent bile acid transporter, and a flow cytometry experiment proved that DC-LIPs are a highly efficient delivery carrier. Caco-2 cells were also used to study the lysosome escape ability of DC-LIPs. We learned from confocal microscopy photographs that DC-LIPs can protect their contents from being destroyed by the lysosome. Finally, according to pharmacokinetic analyses, insulin-loaded DC-LIPs show a significant hypoglycemic effect with an oral bioavailability of 16.1% in rats with type I diabetes.

Anti-Cancer and Protective Effects of Royal Jelly for Therapy-Induced Toxicities in Malignancies

Royal jelly (RJ) is a glandular secretion produced by worker honeybees and is a special food for the queen honeybee. It results in a significant prolongation of the lifespan of the queen honeybee compared with the worker honeybees through anti-inflammatory, anti-oxidant and anti-microbial activities. Consequently, RJ is used as cosmetic and dietary supplement throughout the world. In addition, in vitro studies and animal experiments have demonstrated that RJ inhibits cell proliferation and stimulates apoptosis in various types of malignant cells and affects the production of various chemokines, anti-oxidants and growth factors and the expression of cancer-related molecules in patients with malignancies, especially in patients treated with anti-cancer agents. Therefore, RJ is thought to exert anti-cancer effects on tumor growth and exhibit protective functions against drug-induced toxicities. RJ has also been demonstrated to be useful for suppression of adverse events, the maintenance of the quality of life during treatment and the improvement of prognosis in animal models and patients with malignancies. To understand the mechanisms of the beneficial effects of RJ, knowledge of the changes induced at the molecular level by RJ with respect to cell survival, inflammation, oxidative stress and other cancer-related factors is essential. In addition, the effects of combination therapies of RJ and other anti-cancer agents or natural compounds are important to determine the future direction of RJ-based treatment strategies. Therefore, in this review, we have covered the following five issues: (1) the anti-cancer effects of RJ and its main component, 10-hydroxy-2-decenoic acid; (2) the protective effects of RJ against anti-cancer agent-induced toxicities; (3) the molecular mechanisms of such beneficial effects of RJ; (4) the safety and toxicity of RJ; and (5) the future directions of RJ-based treatment strategies, with a discussion on the limitations of the study of the biological activities of RJ.