Topical Delivery of Ketorolac Tromethamine via Cataplasm for Inflammatory Pain Therapy

Effect of ion pair strategy on transdermal delivery of guanfacine: Which factor dominates drug permeation?

Ion pair is an effective chemical approach to promoting drug transdermal permeation, and the traditional interpretation for its enhanced permeation effect is mainly attributed to counterions altering the physicochemical properties of the drug (lipophilicity, melting point, etc.). In this work, guanfacine (GFC), a non-stimulant for anti-attention deficit and hyperactivity disorder (ADHD), was used as a model drug, and several organic or inorganic acids were designed thereby successfully constructing ion pairs. The transdermal permeation ability of ion pairs through isolated porcine skin was observed and ranked as follows: guanfacine caprylate (GFC-CA) > GFC > guanfacine laurate (GFC-LA) > guanfacine fumarate (GFC-FA) > guanfacine hydrochloride (GFC-HA) > guanfacine palmitate (GFC-PA). The effect of key physicochemical properties (octanol-water partition coefficient, molecular volume, melting point) on the transdermal permeation rate of the model drug was analyzed in detail. In addition, GFC-CA was observed to alter the lipid structure of the skin, suggesting the traditional explanation of the action of ion pair may be inadequate and underrated, and ion pair may also enhance permeation by disrupting skin structure. The intriguing phenomenon is expected to provide a novel approach to achieving precise transdermal drug delivery.

Ocular bioanalysis of moxifloxacin and ketorolac tromethamine in rabbit lacrimal matrix using liquid chromatography-tandem mass spectrometry

Aim: The fixed-dose combination of moxifloxacin (MOXI) and ketorolac tromethamine (KTR) is widely used for the treatment of bacterial keratitis. Thus, a new LC-MS/MS method was developed to determine MOXI and KTR in lacrimal fluid. Methods: Bioanalysis was performed using a Shimadzu 8050 LC-MS/MS in electrospray ionization-positive mode and the method was validated per US FDA guidelines. Isocratic separation was performed with a Waters Symmetry C18 column using methanol and 0.1% formic acid containing deionized water (85:15, v/v). Results & conclusion: An easy, quick and selective method was established and applied to assess the ocular pharmacokinetic profile of a commercially available formulation containing MOXI and KTR. Based on the pharmacokinetic data, this work describes pharmacokinetics-based dosage regimen calculations and their clinical significance.

Network pharmacology integrated with experimental validation revealed the mechanism of Fengshi Gutong Capsule in the treatment of osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Fengshi Gutong Capsule (FSGTC) is a commonly used Chinese medicine for the treatment of joint pain caused by osteoarthritis (OA). However, the mechanism of action of FSGTC for OA remains unclear.

AIM OF THE STUDY

This study aimed to explore the alleviating effects and potential mechanisms of action of FSGTC for OA through data mining, network pharmacology, and in vitro experiments.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) was performed to establish the fingerprints of FSGTC and detect the components of FSGTC absorbed in the blood. The effects of FSGTC on inflammation, immunity, and liver and kidney functions in patients with OA were evaluated by mining clinical data. The potential targets and pathways of FSGTC were screened using network pharmacology. Subsequently, CCK-8 assay, flow cytometry, western blotting, RT-qPCR, ELISA, and immunofluorescence were performed in IL-1β-stimulated chondrocytes for further validation.

RESULTS

Eighty-seven common peaks and 10 components were identified using the HPLC fingerprints of 12 batches of samples, and the similarity was in the range of 0.973-0.998. Retrospective clinical analysis demonstrated a significant reduction in inflammatory response levels among patients with OA who received FSGTC treatment. Network pharmacology analysis revealed that FSGTC potentially targeted processes related to inflammation, oxidative stress, and apoptosis. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT), The nuclear factor-κB (NF-κB), and janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathways were predicted to be the main pathways involved in the therapeutic effects of FSGTC in OA. In vitro, FSGTC-containing serum aided the proliferation of chondrocytes stimulated by IL-1β, while concurrently mitigating apoptosis, suppressing the expression of inflammatory cytokines and oxidative molecules, and inhibiting the degradation of the chondrocyte extracellular matrix (ECM).

CONCLUSIONS

FSGTC alleviates the inflammatory response in patients with OA. This therapeutic effect was attributed to its anti-inflammatory and antioxidant properties, and its ability to promote IL-1β-induced chondrocyte proliferation, inhibit apoptosis, and prevent the degradation of extracellular matrix. These favorable results were associated with the inhibition of the PI3K/AKT, NF-κB, and JAK2/STAT3 signaling pathways.

Polyacrylate-Cholesterol Amphiphilic Derivative: Formulation Development and Scale-up for Health Care Applications

The novel amphiphilic polyacrylate grafted with cholesterol moieties, PAAbCH, previously synthesized, was deeply characterized and investigated in the lab and on a pre-industrial scale. Solid-state NMR analysis confirmed the polymer structure, and several water-based pharmaceutical and cosmetic products were developed. In particular, stable oil/water emulsions with vegetable oils, squalene, and ceramides were prepared, as well as hydrophilic medicated films loaded with diclofenac, providing a prolonged drug release. PAAbCH also formed polyelectrolyte hydrogel complexes with chitosan, both at the macro- and nano-scale. The results demonstrate that this polymer has promising potential as an innovative excipient, acting as a solubility enhancer, viscosity enhancer, and emulsifying agent with an easy scale-up transfer process.

Sodium Leak Channel in Glutamatergic Neurons of the Lateral Parabrachial Nucleus Modulates Inflammatory Pain in Mice

Elevated excitability of glutamatergic neurons in the lateral parabrachial nucleus (PBL) is associated with the pathogenesis of inflammatory pain, but the underlying molecular mechanisms are not fully understood. Sodium leak channel (NALCN) is widely expressed in the central nervous system and regulates neuronal excitability. In this study, chemogenetic manipulation was used to explore the association between the activity of PBL glutamatergic neurons and pain thresholds. Complete Freund's adjuvant (CFA) was used to construct an inflammatory pain model in mice. Pain behaviour was tested using von Frey filaments and Hargreaves tests. Local field potential (LFP) was used to record the activity of PBL glutamatergic neurons. Gene knockdown techniques were used to investigate the role of NALCN in inflammatory pain. We further explored the downstream projections of PBL using cis-trans-synaptic tracer virus. The results showed that chemogenetic inhibition of PBL glutamatergic neurons increased pain thresholds in mice, whereas chemogenetic activation produced the opposite results. CFA plantar modelling increased the number of C-Fos protein and NALCN expression in PBL glutamatergic neurons. Knockdown of NALCN in PBL glutamatergic neurons alleviated CFA-induced pain. CFA injection induced C-Fos protein expression in central nucleus amygdala (CeA) neurons, which was suppressed by NALCN knockdown in PBL glutamatergic neurons. Therefore, elevated expression of NALCN in PBL glutamatergic neurons contributes to the development of inflammatory pain via PBL-CeA projections.

Tablet Geometry Effect on the Drug Release Profile from a Hydrogel-Based Drug Delivery System

In order to achieve the optimal level of effectiveness and safety of drugs, it is necessary to control the drug release rate. Therefore, it is important to discover the factors affecting release profile from a drug delivery system. Geometry is one of these effective factors for a tablet-shaped drug delivery system. In this study, an attempt has been made to answer a general question of how the geometry of a tablet can affect the drug release profile. For this purpose, the drug release process of theophylline from two hundred HPMC-based tablets, which are categorized into eight groups of common geometries in the production of oral tablets, was simulated using finite element analysis. The analysis of the results of these simulations was carried out using statistical methods including partial least squares regression and ANOVA tests. The results showed that it is possible to predict the drug release profile by knowing the geometry type and dimensions of a tablet without performing numerous dissolution tests. Another result was that, although in many previous studies the difference in the drug release profile from several tablets with different geometries was interpreted only by variables related to the surface, the results showed that regardless of the type of geometry and its dimensions, it is not possible to have an accurate prediction of the drug release profile. Also, the results showed that without any change in the dose of the drug and the ingredients of the tablet and only because of the difference in geometry type, the tablets significantly differ in release profile. This occurred in such a way that, for example, the release time of the entire drug mass from two tablets with the same mass and materials but different geometries can be different by about seven times.