Glycols: The ubiquitous solvent for dermal formulations.

Glycols stand out as one of the most commonly employed safe and effective excipients for pharmaceutical and cosmeceutical products. Their widespread adoption can be attributed to their exceptional solvency characteristics and their ability to interact effectively with skin lipids and keratin for permeation enhancement. Notably, propylene glycol enjoys significant popularity in this regard. Ongoing research endeavours have been dedicated to scrutinising the impact of glycols on dermal drug delivery and shedding light on the intricate mechanisms by which glycols enhance skin permeation. This review aims to mitigate the discordance within the existing literature, assemble a holistic understanding of the impact of glycols on the percutaneous absorption of active compounds and furnish the reader with a profound comprehension of the foundational facets pertaining to their skin permeation enhancement mechanisms, while simultaneously delving deeper into the intricacies of these processes.

Amelioration of inflammation through reduction of oxidative stress in rheumatoid arthritis by treating fibroblast-like synoviocytes (FLS) with DMF-loaded PLGA nanoparticles.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory condition, and Dimethyl fumarate (DMF) is known for inducing antioxidant enzymes and reducing reactive oxygen species (ROS). Fibroblast-like synoviocytes (FLS) contribute to joint damage by releasing interleukins (IL-1ß, IL-6, and IL-8) in response to ROS. Given ROS's impact on FLS acquiring an invasive phenotype, our study explored the effects of poly lactic-co-glycolic acid (PLGA) nanoparticles containing DMF on the expression of the HO-1 enzyme and the inflammatory cytokines IL-1ß, IL-6, and IL-8 in FLS cells. METHODS: In this study, we evaluated and compared the impact of Free-DMF and PLGA-DMF, on the gene expression of the HO-1 and inflammatory cytokines (IL-1ß, IL-6, and IL-8) in FLS cells derived from 13 patients with rheumatoid arthritis. qRT-PCR method was used to quantify the gene expression levels. RESULTS: PLGA-DMF nanoparticles demonstrated a significant increase in HO-1 expression and a significant decrease in IL-1ß gene expression. Also, a significant decrease in IL-6 gene expression was seen under the effect of Free-DMF. These results indicate the potential effectiveness of PLGA-DMF nanoparticles in reducing inflammation and improving rheumatoid arthritis symptoms. DISCUSSION: According to the findings, PLGA-DMF nanoparticles are expected to be effective in reducing inflammation and improving the symptoms of rheumatoid arthritis. Also, further studies on other factors affected by oxidative stress such as cell invasion factors and survival factors after the effect of PLGA-DMF nanoparticle are recommended.

Colchicine binding to tubulin from brain homogenates in the presence of the sugars, glycols and metal ions: effect of nickel ions on the tubulin solubility

The fact that glycerol preserves microtubules from depolymerizing in vitro, and that some ions such as Ca(II) and Mg(II), regulate the assembly-disassembly process of these structures, induced us to study the effect of several sugars, glycols and metal ions on solubility and colchicine affinity of tubulin in rat brain homogenates, and of purified microtubular protein. Inhibition of colchicine binding was significant with glycerol, polyethylene glycol 1000 (PEG-2) and the ions A1(III), Co(II), Ni(II), while compounds structurally related to glycero (glucose and sucrose) did not inhibition it. Mannitol, instead, increased the activity a 47% over control. Apparently the presence of some compounds in brain homogenates [PEG-2 (1000) and NI (II)] favored tubulin sedimentation when these latterwere centrifuged at 100,000 x g for 150 min at 20 degrees C, but the form in which tubulin becomes aggregated in the pellet is unknown. Nickel ion madeinsoluble microtubular protein of homogenates and the purified one by more than 90% without causing significant inhibition of the colchicine binding. The sediment containing nickel-treated two cycles purified microtubular protein observed with the electron microscope did not present microtubules, but it revealed the presence of irregular, wavy and streteched structures, but it revealed the presence of irregular, wavy and stretched structures bearing highly dense dotted material. The sediments became soluble in phosphate-glutamate buffer (pH 6.8) and, when incubated in polymerizing conditions, gave rise to microtubules undistinguishable from those prepared with untreated purified protein