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

The Development of a Stable Peptide-Loaded Long-Acting Injection Formulation through a Comprehensive Understanding of Peptide Degradation Mechanisms: A QbD-Based Approach

Quality by design (QbD) serves as a systematic approach to pharmaceutical development, beginning with predefined objectives and emphasizing an understanding of the product based on sound science and risk management. The purpose of this study is to utilize the QbD concept to develop a stable peptide-loaded long-acting injection formulation. An in-depth comprehension of peptide degradation mechanisms was achieved through forced degradation investigations, elucidating (acid) hydrolysis and oxidation as the primary degradation pathways for the peptide ACTY116. The quality built into the product was focused on risk assessment, for which the critical material attributes (CMAs) and critical process parameters (CPPs) associated with the critical quality attributes (CQAs) of each formulation were identified, leading to the development of the corresponding control strategies. CQAs for three LAI (long-acting injectable) formulations were enhanced by taking the right control strategies. The LAI formulation exhibiting the highest stability for ACTY116 was chosen for subsequent pharmacokinetic investigations in rats. The objective of addressing peptide chemical instability and in vivo long-acting release was achieved. For other molecules with susceptible functionalities like amide bonds, amino groups, and hydroxyl groups, the utilization of PLGA-based in situ gel as an LAI formulation for stabilizing molecules provides valuable insights.

Construction and evaluation of a phospholipid-based phase transition in situ gel system for brexpiprazole

The objective of this study was to develop phospholipid-based injectable phase transition in situ gels (PTIGs) for the sustained release of Brexpiprazole (Brex). Phospholipid (Lipoid S100, S100) and stearic acid (SA) were used as the gel matrix which was dissolved in biocompatible solvent medium-chain triglyceride (MCT), N-methyl pyrrolidone (NMP), and ethanol to obtain PTIGs solution. The Brex PTIG showed a solution condition of low viscosity in vitro and was gelatinized in situ in vivo after subcutaneous injection. Both in vitro release assay and in vivo pharmacokinetics study in SD rats displayed that Brex in PTIGs could achieve a sustained release, compared with brexpiprazole solution (Brex-Sol) or brexpiprazole suspension (Brex-Sus). The Brex-PTIGs had good degradability and biocompatibility in vivo with rare inflammation at the injection site. Among the three Brex-PTIG formulations, Brex-PTIG-3 with the SA in the formulation had the greatest gelation viscosity, the lowest initial release rate, and the most stable release profile with sustained release of up to 60 days. The above results indicated that, as a novel drug delivery system, the Brex-PTIGs offered a new option for the clinical treatment of patients with schizophrenia.

Polyphenols in Oral Health: Homeostasis Maintenance, Disease Prevention, and Therapeutic Applications

Polyphenols, a class of bioactive compounds with phenolic structures, are abundant in human diets. They have gained attention in biomedical fields due to their beneficial properties, including antioxidant, antibacterial, and anti-inflammatory activities. Therefore, polyphenols can prevent multiple chronic or infectious diseases and may help in the prevention of oral diseases. Oral health is crucial to our well-being, and maintaining a healthy oral microbiome is essential for preventing various dental and systemic diseases. However, the mechanisms by which polyphenols modulate the oral microbiota and contribute to oral health are still not fully understood, and the application of polyphenol products lies in different stages. This review provides a comprehensive overview of the advancements in understanding polyphenols' effects on oral health: dental caries, periodontal diseases, halitosis, and oral cancer. The mechanisms underlying the preventive and therapeutic effects of polyphenols derived from dietary sources are discussed, and new findings from animal models and clinical trials are included, highlighting the latest achievements. Given the great application potential of these natural compounds, novel approaches to dietary interventions and oral disease treatments may emerge. Moreover, investigating polyphenols combined with different materials presents promising opportunities for developing innovative therapeutic strategies in the treatment of oral diseases.

Effects of green tea extract epigallocatechin-3-gallate (EGCG) on oral disease-associated microbes: a review

For thousands of years, caries, periodontitis and mucosal diseases, which are closely related to oral microorganisms, have always affected human health and quality of life. These complex microbiota present in different parts of the mouth can cause chronic infections in the oral cavity under certain conditions, some of which can also lead to acute and systemic diseases. With the mutation of related microorganisms and the continuous emergence of drug-resistant strains, in order to prevent and treat related diseases, in addition to the innovation of diagnosis and treatment technology, the development of new antimicrobial drugs is also important. Catechins are polyphenolic compounds in green tea, some of which are reported to provide health benefits for a variety of diseases. Studies have shown that epigallocatechin-3-gallate (EGCG) is the most abundant and effective active ingredient in green tea catechins, which acts against a variety of gram-positive and negative bacteria, as well as some fungi and viruses. This review aims to summarize the research progress on the activity of EGCG against common oral disease-associated organisms and discuss the mechanisms of these actions, hoping to provide new medication strategies for the prevention and treatment of oral infectious diseases, the future research of EGCG and its translation into clinical practice are also discussed.

Caries Management with Non-Metallic Nanomaterials: A Systematic Review

BACKGROUND

Non-metallic nanomaterials do not stain enamel or dentin. Most have better biocompatibility than metallic nanomaterials do for management of dental caries.

OBJECTIVE

The objective of this study is to review the types, properties and potential uses of non-metallic nanomaterials systematically for managing dental caries.

METHODS

Two researchers independently performed a literature search of publications in English using PubMed, Scopus and Web of Science. The keywords used were (nanoparticles OR nanocomposites OR nanomaterials) AND (caries OR tooth decay). They screened the titles and abstracts to identify potentially eligible publications of original research reporting non-metallic nanomaterials for caries management. Then, they retrieved and studied the full text of the identified publications for inclusion in this study.

RESULTS

Out of 2497 resulting publications, this study included 75 of those. The non-metallic nanomaterials used in these publications were categorized as biological organic nanomaterials (n=45), synthetic organic nanomaterials (n=15), carbon-based nanomaterials (n=13) and selenium nanomaterials (n=2). They inhibited bacteria growth and/or promoted remineralization. They could be incorporated in topical agents (29/75, 39%), dental adhesives (11/75, 15%), restorative fillers (4/75, 5%), dental sealant (3/75, 4%), oral drugs (3/75, 4%), toothpastes (2/75, 3%) and functional candies (1/75, 1%). Other publications (22/75, 29%) do not mention specific applications. However, most publications (67/75, 89%) were in vitro studies. Six publications (6/75, 8%) were animal studies, and only two publications (2/75, 3%) were clinical studies.

CONCLUSION

The literature showed non-metallic nanomaterials have antibacterial and/or remineralising properties. The most common type of non-metallic nanomaterials for caries management is organic nanomaterials. Non-metallic nanomaterials can be incorporated into dental sealants, toothpaste, dental adhesives, topical agents and even candies and drugs. However, the majority of the publications are in vitro studies, and only two publications are clinical studies.

Effects of the green tea catechin epigallocatechin-3-gallate on Streptococcus mutans planktonic cultures and biofilms: systematic literature review of in vitro studies

This study aimed at performing a systematic review of the literature on the effects of epigallocatechin-3-gallate (EGCG) on Streptococcus mutans planktonic cultures and biofilms. The selected references demonstrated that EGCG suppresses S. mutans acid production by inhibiting the activity of enzymes such as lactate dehydrogenase and FIF0-ATPase. Regarding virulence factors, one study reported a reduction in soluble and insoluble polysaccharide synthesis, another demonstrated that EGCG inhibited GTase activity, and another showed effects of EGCG on the expression of gtf B, C, and D. The effects of EGCG on S. mutans biofilms were reported only by 2 of the selected studies. Moreover, high variability in effective concentrations and microbial assessment methods were observed. The literature suggests that EGCG has effects against S. mutans planktonic cells viability and virulence factors. However, the literature lacks studies with appropriate biofilm models to evaluate the precise effectiveness of EGCG against S. mutans biofilms.

Lignosulfonate Rapidly Inactivates Human Immunodeficiency and Herpes Simplex Viruses

Background: Very few studies of the antiviral potential of lignosulfonates have been published. With the aim of oral application, among various groups of natural products, the relative antiviral potency of lignosulfonate and its ability to rapidly inactivate viruses were investigated. Methods: As target cells, MT-4 cells in suspension and attached Vero cells were used for infections with human immunodeficiency virus (HIV) and human herpes simplex type-1 virus (HSV). Mock- or virus-infected cells were incubated for 3–5 days with various concentrations of test samples, and the viable cell number was determined with the MTT method. For the shorter exposure experiments, higher titers of HIV or HSV were exposed to test samples for 10 or 3 min, diluted to a normal multiplicity of infection (MOI), and applied to the cells. Antiviral activity was quantified by using the chemotherapy index. Results: In the long-exposure system, lignosulfonates showed comparable anti-HIV activity with those of AZT, ddC, and sulfated polysaccharides, and it exceeded those of hundreds of tannins and flavonoids. When the exposure time was shortened, the chemotherapeutic index of the lignosulfonates for HIV was increased 27-fold. At a physiological pH, lignosulfonate showed higher anti-HIV activity than commercial alkali-lignin, dealkali-lignin, and humic acid, possibly due to the higher solubility and purity. Conclusions: With their rapid virus-inactivation capabilities, lignosulfonates may be useful for the prevention or treatment of virally induced oral diseases.