Salivary Extracellular Vesicles: Biomarkers and Beyond in Human Diseases

Extracellular vesicles, as bioactive molecules, have been extensively studied. There are abundant studies in the literature on their biogenesis, secretion, structure, and content, and their roles in pathophysiological processes. Extracellular vesicles have been reviewed as biomarkers for use in diagnostic tools. Saliva contains many extracellular vesicles, and compared with other body fluids, it is easier to obtain in a non-invasive way, making its acquisition more easily accepted by patients. In recent years, there have been numerous new studies investigating the role of salivary extracellular vesicles as biomarkers. These studies have significant implications for future clinical diagnosis. Therefore, in this paper, we summarize and review the potential applications of salivary extracellular vesicles as biomarkers, and we also describe their other functions (e.g., hemostasis, innate immune defense) in both oral and non-oral diseases.

Treg plasticity and human diseases

INTRODUCTION

As a subset of CD4+ T cells, regulatory T cells (Tregs) with the characteristic expression of transcription factor FOXP3 play a key role in maintaining self-tolerance and regulating immune responses. However, in some inflammatory circumstances, Tregs can express cytokines of other T help (Th) cells by internal reprogramming, which is called Treg plasticity. These reprogrammed Tregs with impaired suppressive ability contribute to the progression of diseases by secreting pro-inflammatory cytokines. However, in the tumor microenvironment (TME), such changes in phenotype rarely occur in Tregs, on the contrary, Tregs usually display a stronger suppressive function and inhibit anti-tumor immunity. It is important to understand the mechanisms of Treg plasticity in inflammatory diseases and cancers.

OBJECTIVES

In this review, we summarize the characteristics of different Th-like Tregs and discuss the potential mechanisms of these changes in phenotype. Furthermore, we summarize the Treg plasticity in human diseases and discuss the effects of these changes in phenotype on disease progression, as well as the potential application of drugs or reagents that regulate Treg plasticity in human diseases.

CONCLUSIONS

Treg plasticity is associated with inflammatory diseases and cancers. Regulating Treg plasticity is a promising direction for the treatment of inflammatory diseases and cancers.

Cryotherapy Attenuates Inflammation via the lncRNA SNHG1/miR-9-5p/NFKB1 Regulatory Axis in Periodontal Ligament Cells

Cryotherapy is a common non-pharmacological method to relieve pain and inflammation. Clinical studies have shown that cryotherapy can reduce postoperative pain after root canal therapy, but the mechanism remains unclear. In this study, we aimed to investigate the underlying molecular mechanisms by which cryotherapy reduces inflammation in lipopolysaccharide (LPS)-stimulated periodontal ligament cells through transcriptome sequencing analysis. We found that cryotherapy significantly reduced the expression of multiple proinflammatory cytokines and chemokines, and NFKB1 was the key regulator down-regulated by cryotherapy. Importantly, we discovered that lncRNA SNHG1 expression level significantly decreased after cold treatment. SNHG1 expression was positively related to NFKB1 while negatively correlated with miR-9-5p, which formed a novel ceRNA regulatory pathway. Knockdown of SNHG1 significantly reduced the expression of NFKB1, IL1B, and IL6, while overexpression of SNHG1 significantly increased the expression of these genes. In conclusion, our study demonstrated that cryotherapy can effectively reduce inflammation in LPS-induced periodontal ligament cells by suppressing the lncRNA SNHG1/miR-9-5p/NFKB1 axis.