Inhibition of the receptor for advanced glycation inhibits lipopolysaccharide-mediated High mobility group protein B1 and Interleukin-6 synthesis in human gingival fibroblasts through the NF-κB signaling pathway

A literature review of bioactive substances for the treatment of periodontitis: In vitro, in vivo and clinical studies

Periodontitis is a common chronic inflammatory disease of the supporting tissues of the tooth that involves a complex interaction of microorganisms and various cell lines around the infected site. To prevent and treat this disease, several options are available, such as scaling, root planning, antibiotic treatment, and dental surgeries, depending on the stage of the disease. However, these treatments can have various side effects, including additional inflammatory responses, chronic wounds, and the need for secondary surgery. Consequently, numerous studies have focused on developing new therapeutic agents for more effective periodontitis treatment. This review explores the latest trends in bioactive substances with therapeutic effects for periodontitis using various search engines. Therefore, this study aimed to suggest effective directions for therapeutic approaches. Additionally, we provide a summary of the current applications and underlying mechanisms of bioactive substances, which can serve as a reference for the development of periodontitis treatments.

Communal interaction of glycation and gut microbes in diabetes mellitus, Alzheimer's disease, and Parkinson's disease pathogenesis

Diabetes and its complications, Alzheimer's disease (AD), and Parkinson's disease (PD) are increasing gradually, reflecting a global threat vis-à-vis expressing the essentiality of a substantial paradigm shift in research and remedial actions. Protein glycation is influenced by several factors, like time, temperature, pH, metal ions, and the half-life of the protein. Surprisingly, most proteins associated with metabolic and neurodegenerative disorders are generally long-lived and hence susceptible to glycation. Remarkably, proteins linked with diabetes, AD, and PD share this characteristic. This modulates protein's structure, aggregation tendency, and toxicity, highlighting renovated attention. Gut microbes and microbial metabolites marked their importance in human health and diseases. Though many scientific shreds of evidence are proposed for possible change and dysbiosis in gut flora in these diseases, very little is known about the mechanisms. Screening and unfolding their functionality in metabolic and neurodegenerative disorders is essential in hunting the gut treasure. Therefore, it is imperative to evaluate the role of glycation as a common link in diabetes and neurodegenerative diseases, which helps to clarify if modulation of nonenzymatic glycation may act as a beneficial therapeutic strategy and gut microbes/metabolites may answer some of the crucial questions. This review briefly emphasizes the common functional attributes of glycation and gut microbes, the possible linkages, and discusses current treatment options and therapeutic challenges.

In situ photo-crosslinked hydrogel promotes oral mucosal wound healing through sustained delivery of ginsenoside Rg1

Oral mucosal wounds exhibit an increased susceptibility to inflammation as a consequence of their direct exposure to a diverse range of microorganisms. This causes pain, slow healing, and other complications that interfere with patients' daily activities like eating and speaking. Consequently, patients experience a significant decline in their overall quality of life. Therefore, the pursuit of novel treatment approaches is of great importance. In this study, ginsenoside Rg1, a natural active substance extracted from ginseng root, was chosen as a therapeutic agent. It was encapsulated in a screened photo-crosslinked hydrogel scaffold for the treatment of mucosal defects in the rat palate. The results demonstrated that Rg1-hydrogel possessed excellent physical and chemical properties, and that oral mucosa wounds treated with Rg1-hydrogel exhibited the greatest healing performance, as evidenced by more pronounced wound re-epithelialization, increased collagen deposition, and decreased inflammatory infiltration. Subsequent investigations in molecular biology confirmed that Rg1-hydrogel stimulated the secretion of repair-related factors and inhibited the secretion of inflammatory factors. This study demonstrated that the hydrogel containing ginsenoside Rg1 significantly promotes oral mucosal tissue healing in vivo. Based on the findings, it can be inferred that the Rg1-hydrogel has promising prospects for the therapeutic management of oral mucosal wounds.

Magnolia kobus Extract Suppresses Porphyromonas gingivalis LPS-Induced Proinflammatory Cytokine and MMP Expression in HGF-1 Cells and Regulates Osteoclastogenesis in RANKL-Stimulated RAW264.7 Cells

Clinical prevention is of utmost importance for the management of periodontal diseases. Periodontal disease starts with an inflammatory response in the gingival tissue, and results in alveolar bone destruction and subsequent tooth loss. This study aimed to confirm the anti-periodontitis effects of MKE. To confirm this, we studied its mechanism of action using qPCR and WB in LPS-treated HGF-1 cells and RANKL-induced osteoclasts. We found that MKE suppressed proinflammatory cytokine protein expression by inhibiting the TLR4/NF-κB pathway in LPS-PG-induced HGF-1 cells and blocking ECM degradation by regulating the expression of TIMPs and MMPs. We also confirmed that TRAP activity and multinucleated cell formation were reduced in RANKL-stimulated osteoclasts after exposure to MKE. These results were confirmed by inhibiting TRAF6/MAPK expression, which led to the suppression of NFATc1, CTSK, TRAP, and MMP expression at the gene and protein levels. Our results confirmed that MKE is a promising candidate for the management of periodontal disease based on its anti-inflammatory effects and inhibition of ECM degradation and osteoclastogenesis.

N-acetylcysteine protects human periodontal ligament fibroblasts from pyroptosis and osteogenic differentiation dysfunction through the SIRT1/NF-κB/Caspase-1 signaling pathway

OBJECTIVE

This study was aimed to determine whether N-acetylcysteine (NAC) could inhibit lipopolysaccharides / adenosine triphosphate (ATP)-induced pyroptosis and alleviate the damage of osteogenic differentiation in human periodontal ligament fibroblasts (hPDLFs). Furthermore, this study detected whether NAC acted effectively by modulating the silent information regulator 2 homolog 1 (SIRT1)/ the nuclear factor-κB (NF-κB)/Caspase-1 signaling pathway in hPDLFs.

DESIGN

Cell Counting Kit-8 assay was employed to determine the appropriate concentration of NAC for the follow-up experiments. To explore the effect and the underlying mechanisms of NAC on pyroptosis and osteogenic differentiation in hPDLFs, intracellular reactive oxygen species levels were detected using 2',7'-Dichlorodihydrofluorescein Diacetate kits. Moreover, SIRT1 inhibitor, SIRT1 activator, NF-κB inhibitor and Caspase-1 inhibitor were applied, the incidence of pyroptosis was detected by flow cytometry, the osteogenic differentiation of hPDLFs was observed using alkaline phosphatase and alizarin red staining, Real-time quantitative polymerase chain reaction and Western Blot were used to detect the expression of relevant factors, the release of interleukin-1β, interleukin-18 and lactate dehydrogenase were detected by Enzyme-linked immunosorbent assay.

RESULTS

The results demonstrated that NAC protected hPDLFs from lipopolysaccharides/ATP-induced damage, alleviating pyroptosis and osteogenic differentiation dysfunction. Moreover, NAC abrogated the inhibition of SIRT1 activity by scavenging reactive oxygen species, thereby reduced pyroptosis and osteogenic differentiation dysfunction by inhibiting the NF-κB/Caspase-1signaling pathway.

CONCLUSION

NAC could inhibit pyroptosis and osteogenic differentiation dysfunction of hPDLFs by scavenging reactive oxygen species to regulate the SIRT1/NF-κB/Caspase-1 signaling axis.

Inhibitor of RAGE and glucose‑induced inflammation in bone marrow mesenchymal stem cells: Effect and mechanism of action

The occurrence and development of hyperglycemia‑induced inflammation is associated with increased expression of receptor for advanced glycation end products (RAGE) and inflammatory factors, including IL‑1β, TNF‑α and IL‑6. Previous studies have reported that the nucleotide‑binding oligomerization domain‑like receptor protein 3 (NLRP3) inflammasome interacts with thioredoxin‑interacting protein (TXNIP) and serves a crucial role in inflammation. FPS‑ZM1 has been identified as target inhibitor of RAGE and has been shown to exert an anti‑inflammatory effect in vitro. However, the underlying mechanism by which FPS‑ZM1 impacts high glucose (HG)‑induced inflammation in bone marrow mesenchymal stem cells (BMSCs) remains unclear. The present study explored the regulatory effect of FPS‑ZM1 on HG‑induced inflammation in BMSCs. Furthermore, the role of the TXNIP/NLRP3 inflammasome signaling pathway in the regulatory effects of FPS‑ZM1 on HG‑induced inflammation was studied. Cell viability was determined using Cell Counting Kit‑8 and western blotting was used to assess the protein expression levels of RAGE. ELISA was used to determine the levels of inflammatory markers. Reverse transcription‑quantitative PCR and western blotting were used to measure the mRNA and protein expression levels of TXNIP, caspase‑1, thioredoxin (TRX), NLRP3 and apoptosis‑related speck‑like protein containing CARD (ASC). The results revealed that in BMSCs, RAGE expression was stimulated by HG, an effect which was reversed by treatment with FPS‑ZM1. In addition, HG activated inflammatory factors, such as TNF‑α, IL‑1β and IL‑6; however, their levels were suppressed when cells were treated with FPS‑ZM1 or the TXNIP/NLRP3 pathway inhibitor, resveratrol (Res). Furthermore, FPS‑ZM1 inhibited the mRNA and protein expression levels of TXNIP, caspase‑1, NLRP3 and ASC, and promoted TRX expression, which was consistent with the effects of Res. These findings indicated that FPS‑ZM1 may attenuate HG‑induced inflammation in BMSCs. Furthermore, the TXNIP/NLRP3 inflammasome signaling pathway mediated the molecular mechanism underlying this effect.

N‑acetyl cysteine inhibits the lipopolysaccharide‑induced inflammatory response in bone marrow mesenchymal stem cells by suppressing the TXNIP/NLRP3/IL‑1β signaling pathway

N-acetyl cysteine (NAC) has been used to inhibit lipopolysaccharide (LPS)-induced inflammation. However, the molecular mechanism underlying its anti-inflammatory effects remains to be elucidated. The present study aimed to determine the effect of NAC on the LPS-induced inflammatory response in bone marrow mesenchymal stem cells (BMSCs) and elucidate the underlying molecular mechanism. First, BMSCs were stimulated by LPS following pretreatment with NAC (0, 0.1, 0.5, 1 or 2 mM). A Cell Counting Kit 8 assay was used to determine the number of viable cells and 1 mM NAC was selected as the experimental concentration. Then, the secretion of inflammatory factors, including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α was evaluated by enzyme-linked immunosorbent assay. Finally, the expression levels of mRNA and proteins, including apoptosis-associated speck-like protein containing a CARD (ASC), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), caspase-1, thioredoxin-interacting protein (TXNIP), and thioredoxin (TRX), were evaluated by reverse transcription-quantitative PCR and western blot analysis, respectively. The results demonstrated that the secretion of inflammatory factors, which was increased by the administration of LPS, was reduced by pretreatment with NAC. Furthermore, NAC reduced the expression of ASC, NLRP3, caspase-1 and TXNIP, but enhanced that of TRX. To conclude, NAC had anti-inflammatory effects on LPS-stimulated BMSCs, which was closely associated with the TXNIP/NLRP3/IL-1β signaling pathway. Thus, NAC may be a promising treatment to attenuate the inflammatory response in LPS-induced BMSCs.

Calcific Aortic Valve Disease-Natural History and Future Therapeutic Strategies

Calcific aortic valve disease (CAVD) is the most frequent heart valve disorder. It is characterized by an active remodeling process accompanied with valve mineralization, that results in a progressive aortic valve narrowing, significant restriction of the valvular area, and impairment of blood flow.The pathophysiology of CAVD is a multifaceted process, involving genetic factors, chronic inflammation, lipid deposition, and valve mineralization. Mineralization is strictly related to the inflammatory process in which both, innate, and adaptive immunity are involved. The underlying pathophysiological pathways that go from inflammation to calcification and, finally lead to severe stenosis, remain, however, incompletely understood. Histopathological studies are limited to patients with severe CAVD and no samples are available for longitudinal studies of disease progression. Therefore, alternative routes should be explored to investigate the pathogenesis and progression of CAVD.Recently, increasing evidence suggests that epigenetic markers such as non-coding RNAs are implicated in the landscape of phenotypical changes occurring in CAVD. Furthermore, the microbiome, an essential player in several diseases, including the cardiovascular ones, has recently been linked to the inflammation process occurring in CAVD. In the present review, we analyze and discuss the CAVD pathophysiology and future therapeutic strategies, focusing on the real and putative role of inflammation, calcification, and microbiome.