Clinical Development and Evaluation of a Multi-Component Dissolving Microneedle Patch for Skin Pigmentation Disorders.

Excessive melanin deposition in the skin leads to various skin pigmentation diseases, such as chloasma and age spots. The deposition is induced by several factors, including tyrosinase activities and ultraviolet-induced oxidative stress. Herein, we propose a multi-component, multi-pathway drug combination, with glabridin, 3-O-ethyl-L-ascorbic acid, and tranexamic acid employed as, respectively, a tyrosinase inhibitor, an antioxidant, and a melanin transmission inhibitor. Considering the poor skin permeability associated with topical application, dissolving microneedles (MNs) prepared with hyaluronic acid/poly(vinyl alcohol)/poly(vinylpyrrolidone) were developed to load the drug combination. The drug-loaded microneedles (DMNs) presented outstanding skin insertion, dissolution, and drug delivery properties. In vitro experiments confirmed that DMNs loaded with active ingredients had significant antioxidant and inhibitory effects on tyrosinase activity. Furthermore, the production of melanin both in melanoma cells (B16-F10) and in zebrafish was directly reduced after using DMNs. Clinical studies demonstrated the DMNs' safety and showed that they have the ability to effectively reduce chloasma and age spots. This study indicated that a complex DMN based on a multifunctional combination is a valuable depigmentation product worthy of clinical application.

Aspirin microcrystals deposited on high-density microneedle tips for the preparation of soluble polymer microneedles.

To reduce mucosal damage in the gastrointestinal tract caused by aspirin, aspirin microcrystals were loaded in soluble polymeric microneedle (MN) tips. Aspirin was prepared into aspirin microcrystals by jet milling. Aspirin microcrystals with particle sizes of 0.5-5 µm were loaded on MN tips with a height of 250 µm or 300 µm. The aspirin microcrystals suspended in a polymer solution were concentrated in the MN tips under negative pressure. The aspirin microcrystals had high stability in the MNs since they were not dissolved in solution during the fabrication process. The MN patch packaged in an aluminum-plastic bag containing silica gel desiccant can be stored at 4 °C. The MN tips implanted in the skin of Institute of Cancer Research (ICR) mice dissolved within 30 min. Isolated porcine ear skin was punctured by MNs with heights of 300 µm and 250 µm to depths of 130 µm and 90 µm, respectively. The fluorescent red (FR) release from MNs reached 98.59% within 24 h. The MNs delivered aspirin microcrystals to the epidermis and dermis, providing a smooth plasma concentration in rats. The MNs loaded with aspirin microcrystals did not evoke primary irritation on the dorsal skin of Japanese white rabbits. In summary, MNs loaded with aspirin microcrystals provide a new approach to improve the stability of aspirin in MN patches.

Circ_0003028 enhances the proliferation and glycolytic capacity and suppresses apoptosis in non-small cell lung cancer cells via the miR-1305/miR-1322-SLC5A1 axis.

Background: Circular RNA (circRNA), a unique RNA molecule with a circular structure, is relevant to the process of non-small cell lung cancer (NSCLC). However, the role and possible mechanisms of circ_0003028 in NSCLC are not completely clear. Here, we investigated the role of circ_0003028 in NSCLC progression. Methods: We first confirmed the stability and head-to-tail junction sequences of circ_000302. Circ_0003028 expression was identified with quantitative reverse transcription polymerase chain reaction (qRT-PCR) in NSCLC tissues, and the survival probability and prognosis were analyzed using Kaplan-Meier survival and receiver operating characteristic (ROC) analyses. Functionally, the proliferation, apoptosis, and glycolytic capacity were examined using cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU) staining, a flow cytometer, commercial kits [glucose, lactate, and adenosine triphosphate (ATP)], and a Seahorse XF extracellular flux analyzer. Moreover, the potential microRNAs (miRNAs) of circ_0003028 were predicted and identified, and the target gene of miRNA (miR)-1322 and miR-1305 were also screened using DIANA-microT and TargetScan. Results: We first determined the head-to-tail junction sequences of circ_0003028 and its stability. Circ_0003028 was also confirmed to be upregulated in NSCLC tissues. Meanwhile, circ_0003028 had poor overall survival and high diagnostic potential in NSCLC patients. Furthermore, we found that overexpression of circ_0003028 could increase the proliferation and glycolytic capacity and restrain the apoptosis of NSCLC cells, and circ_0003028 silencing played the opposite role to circ_0003028 overexpression. Moreover, circ_0003028 might regulate miR-1305 and miR-1322, which might further regulate solute carrier family 5 member 1 (SLC5A1). Conclusions: Circ_0003028 could accelerate the malignant behaviors and glycolytic capacity of NSCLC cells via a mechanism that may be related to miR-1305 or the miR-1322/SLC5A1 axis. Therefore, the findings of the current study provide a preliminary theoretical basis for NSCLC therapy and diagnosis.

Thermal stability of exenatide encapsulated in stratified dissolving microneedles during storage.

As low-temperature storage and transportation of peptides require high costs, improving the dosage form of peptides can reduce costs. We developed a thermostable and fast-releasing stratified dissolving microneedle (SDMN) system for delivering exenatide (EXT) to patients with type 2 diabetes. Among the tested polymers, dextran and polyvinyl alcohol (PVA) were the best at stabilizing EXT under high-temperature storage for 9 weeks. The two polymers possess a relatively high glass transition temperature (Tg) and weak hydrogen bonding between PVA and EXT. Additionally, zinc sulfate (ZnSO4) had a stabilizing effect on EXT among the selected stabilizers, suggesting that EXT formed a dimer after coordination with zinc ions (Zn2+). In addition, the denaturation temperature (Tm) of EXT was increased by adding ZnSO4, thus stabilizing EXT. Accordingly, SDMNs consisting of a tip layer (dextran encapsulating the Zn2+-EXT complex) and a base layer (PVA) were fabricated. Within 2 min of implantation, the EXT loaded on the patch was quickly released into the skin. Transdermal pharmacokinetics studies showed that manufactured SDMNs generated comparable efficacy to subcutaneous injection. Significantly, the remaining EXT amount was not significantly different under storage at 40 °C and -20 °C for 3 months, supporting that the SDMN system had excellent delivery efficiency and stability, thus reducing the dependence on the cold chain.

Emerging role of N6-methyladenosine RNA methylation in lung diseases.

In recent years, with the increase of air pollution, smoking, aging, and respiratory infection, the incidence rate and mortality of lung diseases are increasing annually, which has become a major hazard to human health. N6-methyladenosine (m6A) RNA methylation is the most abundant modifications in eukaryotes, and such modified RNA can be specifically recognized and combined by m6A recognition proteins and then mediate RNA splicing, maturation, enucleation, degradation, and translation. More and more studies have revealed that the m6A modification is involved in the pathogenesis and development of some diseases; however, the mechanisms of m6A in lung diseases are poorly understood. In this review, we summarize the latest progress in the biological function of m6A modifications in lung diseases and discuss the potential therapeutic and prognostic strategies. The dysregulation of global m6A levels and m6A regulators may affect the occurrence and development of asthma, chronic obstructive pulmonary disease, lung cancer, and other lung diseases through inflammation and immune function. In lung cancer, this modification has an important impact on malignant cell proliferation, migration, invasion, and drug resistance. In addition, abnormally changed m6A-modified proteins in lung cancer tissue samples and circulating tumor cells (CTCs) may be used as diagnostic and prognostic markers of lung cancer. Models composed of multiple m6A regulators can be used to evaluate the risk prediction or prognosis of asthma and pulmonary fibrosis. In general, the in-depth study of m6A modifications is a frontier direction in disease research. It provides novel insights for understanding of the molecular mechanisms underlying disease occurrence, development, and drug resistance, as well as for the development of effective novel therapeutics.