Combined signatures of serum proteome and transcriptome in patients with recurrent aphthous ulcer

Novel Serum Markers that Distinguish Behcet's Disease from Idiopathic Recurrent Aphthous Stomatitis

BACKGROUND

Behcet's disease (BD) is a rare and recurrent autoinflammatory disorder characterized by systemic vasculitis, frequently manifested as recurrent aphthous stomatitis (RAS). We aim to identify specific serum proteins to discriminate between BD and idiopathicRAS.

METHOD

Peripheral blood was collected from 12 BD patients, 12 idiopathic RAS patients, and 21 healthy volunteers. The serum samples underwent Tandem Mass Tag-based mass spectrometry analysis. Differentially expressed proteins (DEPs) were identified for KEGG pathway enrichment, Gene Ontology (GO), and protein-protein interaction (PPI) analyses. ELISA was utilized to verify two BD-specific DEPs in another cohort consisting of 18 BD patients, 18 idiopathic RAS patients, and 18 controls.

RESULTS

Compared with RAS serum, BD serum showed 242 DEPs. 49 proteins were differentially expressed in BD but not RAS serum compared to healthy controls. KEGG pathway and GO analyses revealed that DEPs in BD and RAS have similar biological functions and cellular distributions, featuring a significant association with pathways regulating blood coagulation and immune response. When comparing DEPs between BD and RAS, several keratins emerged as markers that distinguish RAS from BD. We also identified multiple DEPs in BD but not RAS patients. PPI analysis uncovered that lipoprotein metabolism regulators serve as hub proteins, indicating their potentially essential roles in BD pathology. In addition, ELISA results confirmed the elevated LRG1 and SOD3 levels in BD, but not RAS patients, compared to healthy donors.

CONCLUSION

Our data uncovered novel serum proteins that distinguish BD from RAS, which may potentially be useful in BD diagnosis and treatment.

Evaluation of biochemical variables in patients with recurrent aphthous stomatitis

PURPOSE

We investigated the effects of various biochemical agents on the etiopathogenesis of recurrent aphthous stomatitis (RAS).

METHODS

We enrolled 70 RAS patients and 70 healthy volunteers. Peripheral venous blood samples were collected. We performed complete blood counts, then measured the levels of ferritin, vitamin B12, iron, magnesium, phosphorus, calcium, thyroid-stimulating hormone, T3, T4, and 25-hydroxy D3.

RESULTS

The groups did not differ in terms of age (p = 0.912) or sex (p = 0.612). The levels of ferritin and 25-hydroxy vitamin D were significantly lower in RAS patients (both p ˂ 0.05).

CONCLUSION

Vitamin D and/or ferritin deficiency may induce RAS. Measurements of vitamin D and ferritin may assist diagnosis and follow-up.

A Randomized controlled clinical trial on dose optimization of thalidomide in maintenance treatment for recurrent aphthous stomatitis

BACKGROUND

Recurrent aphthous stomatitis (RAS) is the most common oral mucosal disease, and ulcer-free periods are a major concern for patients. Thalidomide has been shown to be an effective systemic drug in the treatment of RAS, but the value of undertaking a trial to evaluate various maintenance doses was warranted.

METHODS

We performed this randomized controlled clinical trial with a two-stage design. Firstly, all the 125 cases of RAS received prednisone at a starting dose of 15 mg/d for one week as an initial therapeutic drug. Secondly, the 100 cases of RAS in the experimental group received thalidomide (50 mg/d vs. 25 mg/d) as a maintenance drug to observe its efficacy and safety.

RESULTS

During maintenance medication at the fourth and eighth weekend, the two doses (50 and 25 mg/d) of thalidomide were equivalent in reducing the incidence of ulcers, ulcer number, and ulcer pain, respectively (all p > 0.05). Notably, the ulcer-free period in the group using 25 mg/d thalidomide for eight weeks was longer (mean, >3 months) than those in the other groups (all p < 0.05). Importantly, the total adverse events in the group using 25 mg/d thalidomide were significantly less than those in the group using 50 mg/d (p < 0.001). Moreover, the effect of 50 mg/d thalidomide on the levels of various salivary cytokines was not superior to 25 mg/d medication (p > 0.05).

CONCLUSION

This dose optimization study concluded that 25 mg/d thalidomide had a long-term effect on extending the recurrence interval of RAS with better safety.

Salivary proteome of aphthous stomatitis reveals the participation of vitamin metabolism, nutrients, and bacteria

There are currently no preventative options for recurrent aphthous stomatitis, and the only available treatments are palliative. This is partly due to a poor understanding of its etiopathogenesis. In this case-control study, we characterized the salivary proteome of patients with recurrent aphthous stomatitis in the presence and absence of lesions. Through mass spectrometry-based proteomics and bioinformatics tools, we identified that the presence of oral ulcers is associated with several specific biological processes, including the metabolic pathways of vitamin B9, B12, nitrogen, selenium, and the bacterium Neisseria meningitidis. These changes occurred only in the presence of clinically visible lesions, and there were no relevant differences between patients in anatomical regions unaffected by ulcers. Additionally, using western blot and ELISA assays, we verified that carbonic anhydrase 1 (CA1) and hemoglobin subunit beta (HBB) proteins are highly expressed during the ulcerative and remission phases of recurrent aphthous stomatitis. Our results cumulatively support saliva as an indicator of the pathophysiological changes, which occur during the clinical course of lesions. From a clinical perspective, we suggest that recurrent aphthous stomatitis is a condition triggered by temporary biological changes in people with lesions.