Vasohibin-1 promotes osteoclast differentiation in periodontal disease by stimulating the expression of RANKL in gingival fibroblasts.

Vasohibin-1 (VASH1) is a key inhibitor of vascular endothelial growth factor-induced angiogenesis. Although the involvement of VASH1 in various pathological processes has been extensively studied, its role in periodontal disease (PD) remains unclear. We aimed to investigate the role of VASH1 in PD by focusing on osteoclastogenesis regulation. We investigated VASH1 expression in PD by analyzing data from the online Gene Expression Omnibus (GEO) database and using a mouse ligature-induced periodontitis model. The effects of VASH1 on osteoclast differentiation and osteoclastogenesis-supporting cells were assessed in mouse bone marrow-derived macrophages (BMMs) and human gingival fibroblasts (GFs). To identify the stimulant of VASH1, we used culture broth from Porphyromonas gingivalis (Pg), a periopathogen. The GEO database and mouse periodontitis model revealed that VASH1 expression was upregulated in periodontitis-affected gingival tissues, which was further supported by immunohistochemistry and qRT-PCR analyses. VASH1 expression was significantly stimulated in GFs after treatment with the Pg broth. Direct treatment with recombinant VASH1 protein did not stimulate osteoclast differentiation in BMMs but did contribute to osteoclast differentiation by inducing RANKL expression in GFs through a paracrine mechanism. Small interfering RNA-mediated silencing of VASH1 in GFs abrogated RANKL-mediated osteoclast differentiation in BMMs. Additionally, VASH1-activated RANKL expression in GFs was significantly suppressed by MK-2206, a selective inhibitor of AKT. These results suggest that Pg-induced VASH1 may be associated with RANKL expression in GFs in a paracrine manner, contributing to osteoclastogenesis via an AKT-dependent mechanism during PD progression.

Prevalence of Dysphonia in Children with Adenotonsillar Problems and the Impact of Surgery on Voice.

OBJECTIVE/HYPOTHESIS: Adenotonsillar problems might affect the voices of patients with pediatric dysphonia, which is very common. This study aimed to evaluate the prevalence of dysphonia in patients with adenotonsillar problems and to demonstrate the impact of tonsillectomy and adenoidectomy (T & A) on their voice postoperatively. STUDY DESIGN: Single-institution retrospective study. METHODS: Subjects were recruited from those children admitted for the purpose of T & A, and all underwent the auditory-perceptual assessment by speech therapists preoperatively. If children demonstrated scores >2 in the G parameter, we performed subjective (pediatric voice handicap index [pVHI], severity, talkativeness scale) and objective (Multi-Dimensional Voice Program) voice analyses preoperatively and 1 and 3 months postoperatively. RESULTS: Among the 1,197 patients, 91 (7.6%) patients showed dysphonia with a score >2 in the G parameter preoperatively. The follow-up voice analysis was completed in 51 and 22 patients after 1 and 3 months, respectively. Although there were no significant differences in the amount of speech preoperatively and postoperatively, the average visual analog scale score for dysphonia severity was significantly decreased at postoperative 1 month and postoperative 3 months. The average total pVHI score, jitter, shimmer, noise-to-harmonic ratio, and soft phonation index were significantly decreased at 1 and 3 months postoperatively. Subjective scores given by parents did not correlate with the acoustic parameters; however, the postoperative subjective parameters were significantly correlated with objective parameters. CONCLUSIONS: Voice problems were significantly improved after T & A in the short term and long term. In those with pediatric dysphonia, decreased mouth breathing and compliance with vocal hygiene would be helpful for voice improvement. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2369-2375, 2021.

Tricarbonyldichlororuthenium(II) dimer, the lipid-soluble carbon monoxide-releasing molecule, attenuates Prevotella intermedia lipopolysaccharide-induced production of nitric oxide and interleukin-1ß in murine macrophages.

Carbon monoxide (CO) is increasingly being appreciated as an important mediator that has pleiotropic biological properties and appears to have a possible therapeutic application for a variety of disorders. Nevertheless, whether this gaseous molecule may be utilized as a therapeutic intervention for periodontal disease is unclear. Here, we examined the potential beneficial effect of CO-releasing molecule-2 (CORM-2), a tricarbonyldichlororuthenium(II) dimer, against the elaboration of proinflammatory mediators by murine macrophages challenged with lipopolysaccharide (LPS) isolated from Prevotella intermedia, a pathogenic bacterium implicated in inflammatory periodontal disease. We found that NO and IL-1ß production, iNOS protein expression and mRNA expressions of iNOS and IL-1ß were significantly down-regulated when LPS-challenged RAW264.7 cells were exposed to CORM-2. In addition, HO-1 expression was upregulated by CORM-2 in cells activated with P. intermedia LPS, and the inhibitory influence of CORM-2 upon NO production was attenuated by tin protoporphyrin IX, an inhibitor of HO activity. PPAR-γ did not function in the attenuation of NO and IL-1ß by CORM-2. JNK and p38 phosphorylation caused by LPS was not altered by CORM-2. CORM-2 reduced NF-κB reporter activity and IκB-α degradation elicited by P. intermedia LPS. Additionally, CORM-2 inhibited LPS-induced phosphorylation of STAT1/3. In conclusion, CORM-2 suppresses NO and IL-1ß production caused by P. intermedia LPS. CORM-2 exerts its effect by a mechanism involving anti-inflammatory HO-1 induction and attenuation of NF-κB and STAT1/3 activation, independently of PPAR-γ as well as JNK and p38. CORM-2 may hold promise as host response modulation agent for periodontal disease, though further research is indicated to verify the therapeutic effect.