Sulfasalazine in dermatology: A lesser explored drug with broad therapeutic potential

Successful treatment of erythema nodosum with salazosulfapyridine in a 9-year-old patient with chronic non-bacterial osteomyelitis

We report a 9-year-old Japanese girl with chronic non-bacterial osteomyelitis (CNO) accompanied by recurrent erythema nodosum (EN) which was successfully treated with salazosulfapyridine (SASP). She was referred to our hospital because of recurrent erythema on her lower extremities and persistent knee and ankle arthralgia, which had been present for approximately 1 year. Although naproxen, a nonsteroidal anti-inflammatory drug, was initiated, her symptoms frequently recurred. Magnetic resonance imaging demonstrated multiple distinct high-intensity signals in the talus bones suggestive of multiple bone oedemas. Additionally, a histological examination of erythematous lesions was consistent with the histopathological findings of EN. She was diagnosed as having CNO complicated by EN, and received 250 mg/day of SASP as a second-line treatment, which showed partial response of both skin and bone lesions. Following increase in the dose of SASP to 500 mg/day resulted in complete remission of her skin and bone lesions. In conclusion, our findings suggest that SASP is effective not only for CNO bone lesions but also for EN. SASP could serve as a second-line therapeutic option at least for some cases of CNO complicated by EN refractory to nonsteroidal anti-inflammatory drugs.

Transcriptomics- and Genomics-Guided Drug Repurposing for the Treatment of Vesicular Hand Eczema

Vesicular hand eczema (VHE), a clinical subtype of hand eczema (HE), showed limited responsiveness to alitretinoin, the only approved systemic treatment for severe chronic HE. This emphasizes the need for alternative treatment approaches. Therefore, our study aimed to identify drug repurposing opportunities for VHE using transcriptomics and genomics data. We constructed a gene network by combining 52 differentially expressed genes (DEGs) from a VHE transcriptomics study with 3 quantitative trait locus (QTL) genes associated with HE. Through network analysis, clustering, and functional enrichment analyses, we investigated the underlying biological mechanisms of this network. Next, we leveraged drug-gene interactions and retrieved pharmaco-transcriptomics data from the DrugBank database to identify drug repurposing opportunities for (V)HE. We developed a drug ranking system, primarily based on efficacy, safety, and practical and pricing factors, to select the most promising drug repurposing candidates. Our results revealed that the (V)HE network comprised 78 genes that yielded several biological pathways underlying the disease. The drug-gene interaction search together with pharmaco-transcriptomics lookups revealed 123 unique drug repurposing opportunities. Based on our drug ranking system, our study identified the most promising drug repurposing opportunities (e.g., vitamin D analogues, retinoids, and immunomodulating drugs) that might be effective in treating (V)HE.

Interaction of sulfasalazine with outer surface of boron-nitride nanotube as a drug carrier in aqueous solution: insights from quantum mechanics and Monte Carlo simulation

The improvement of the solubility of sulfasalazine in physiological media was the major aim of this study. Accordingly, BNNT inspected as a notable candidate for the carriage of this drug in aqueous media. For this purpose, four possible interactions of two tautomer of sulfasalazine with (9,0) boron-nitride nanotube were considered in aqueous media. The compounds were optimized in gas phase using density functional calculations. Solvation free energies and association free energies of the optimized structures were then studied by Monte Carlo simulation and perturbation method in water environment. Outcomes of quantum mechanical calculations presented that interaction of keto form of sulfasalazine produce the most stable complexes with boron-nitride nanotube in gas phase. Simulation results revealed that electrostatic interactions play a vital role in the intermolecular interaction energies after binding of drug and nanotube in aqueous solution. Results of association free energy calculations indicated that complexes of both two sulfasalazine tautomers (keto and enol) and nanotube were stable in solution. Computed solvation free energies in water showed that the interaction with boron-nitride nanotube significantly improved the solubility of sulfasalazine, which could improve its in vivo bioavailability.

Systematic identification of anticancer drug targets reveals a nucleus-to-mitochondria ROS-sensing pathway

Multiple anticancer drugs have been proposed to cause cell death, in part, by increasing the steady-state levels of cellular reactive oxygen species (ROS). However, for most of these drugs, exactly how the resultant ROS function and are sensed is poorly understood. It remains unclear which proteins the ROS modify and their roles in drug sensitivity/resistance. To answer these questions, we examined 11 anticancer drugs with an integrated proteogenomic approach identifying not only many unique targets but also shared ones-including ribosomal components, suggesting common mechanisms by which drugs regulate translation. We focus on CHK1 that we find is a nuclear H2O2 sensor that launches a cellular program to dampen ROS. CHK1 phosphorylates the mitochondrial DNA-binding protein SSBP1 to prevent its mitochondrial localization, which in turn decreases nuclear H2O2. Our results reveal a druggable nucleus-to-mitochondria ROS-sensing pathway-required to resolve nuclear H2O2 accumulation and mediate resistance to platinum-based agents in ovarian cancers.

Central composite design-based optimization, fabrication, and pharmacodynamic assessment of sulfasalazine-loaded lipoidal nanoparticle-based hydrogel for the management of rheumatoid arthritis

Rheumatoid arthritis is a progressive, chronic, immunological, and inflammatory disorder that is distinguished by joint inflammation, joint tenderness, and synovial joint destruction. The study aimed to fabricate sulfasalazine-loaded solid lipid nanoparticle (SLN)-based gels for rheumatoid arthritis management. The SLNs were fabricated with the melt emulsification technique by employing central composite design (CCD) for SLNs optimization. The optimized formulation of SLNs (FF-1) showed particle size and drug entrapment efficiency of 117.25 nm ± 1.67 and 94.05% ± 1.05, respectively. To scrutinize the outcome of the independent variable on responses; model graphs and the polynomial equation obtained from the Design-Expert were used. The surface morphology studies of SLNs revealed a smooth surface with a slightly asymmetric shape. In vitro drug release of the optimized formulation (FF1) had shown a maximum release of up to ~ 91.89% ± 2.12 over 24 h. The optimized FF1 formulation was subsequently gelled using 1% w/v Carbopol 934 and subjected to ex vivo permeation that displayed 8.01 mg/cm² ± 0.24 and 7.49 mg/cm² ± 0.86 amount of drug permeated up to 24 h and 10 h from SLNs gel and plain gel, respectively. In vivo studies manifested a considerable reduction in the paw thickness (*p < 0.0001) and an arthritic score (*p < 0.0001) of the sulfasalazine SLN gel as compared to plain gel. Further, pro-inflammatory cytokines, viz. TNF-α, IL-1, and IL-6 levels, were significantly inhibited (p < 0.0001) by sulfasalazine SLN-based gel that exhibited substantial anti-inflammatory effects. In conclusion, sulfasalazine-loaded SLN-based gel showed sustained release of drug for up to 24 h and can be considered suitable as a topical application for rheumatoid arthritis management.

Pro and contra: is synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) a spondyloarthritis variant?

PURPOSE OF REVIEW

The purpose of this review is to present the up-to-date evidence on the epidemiology, pathogenesis, musculoskeletal manifestations, and imaging of the synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and to discuss its relationship with spondyloarthritis (SpA).

RECENT FINDINGS

SAPHO is a rare inflammatory disorder of bone, joints, and skin, with a worldwide distribution that predominantly affects the middle-age adults. The hallmark of the syndrome is a constellation of sterile inflammatory osteitis, hyperostosis, and synovitis involving the anterior chest wall, associated with acneiform and neutrophilic dermatoses, such as palmoplantar pustulosis and severe acne. The axial skeleton, sacroiliac, and peripheral joints can be involved in a similar fashion to SpA. The pathogenesis of the syndrome is multifactorial. The diagnosis is mainly based on the clinical and typical radiological features. The treatment approach is based on the off-label use of antibiotics, bisphosphonates, disease-modifying antirheumatic drugs, and anticytokine biologics.

SUMMARY

The SAPHO syndrome shares common features with SpA-related diseases, yet also shows some unique pathogenetic and clinical features. The nosology of SAPHO remains a subject of controversy, awaiting further research into the pathogenetic and clinical aspects of this syndrome. A better understanding of these aspects will improve the diagnostics and clinical care of patients with SAPHO.

SAPHO Syndrome and Pustulotic Arthro-Osteitis (PAO)

Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO) syndrome is a rare inflammatory osteo-articular disorder, which encompassed many diseases, including pustulotic arthro-osteitis (PAO). Bone and joint manifestations, including osteitis, synovitis and hyperostosis, are the hallmark of the SAPHO syndrome and affect a variety of regions of the body. Recent GRAPPA survey indicated that more than 80 percent of cases of SAPHO syndrome in Japan were thought to be PAO, originally proposed by Sonozaki et al. in 1981, whereas severe acne was the most commonly reported skin ailment amongst participants with SAPHO syndrome in Israel. SAPHO syndrome is a rare disease and adequate data regarding its prevalence remains unavailable, whereas prevalence of PPP was reported to be 0.12 % in Japan and 10-30% of patients with PPP had PAO. SAPHO syndrome and PAO are predominantly found in patients in the third through fifth decades of life, and a female predominance are seen in both groups. The diagnosis of SAPHO syndrome/PAO is typically made by a rheumatologist or dermatologist. Identification of a variety of the clinical, radiological, and laboratory features outlined, as well as diagnostic criteria, are used to make the diagnosis. Goals for treating patients with SAPHO syndrome/PAO seek to maximize health-related quality of life by improving skin and articular symptoms, preventing structural changes and destruction, and normalizing physical function and social participation. Finally, we review the non-pharmacological (ie: smoking cessation and controlling focal infections) and pharmacological managements including NSAIDs, bisphosphonates, cs DMARDs, bDMARDs, and other treatments for SAPHO syndrome/PAO.