Wnt5a up-regulates Periostin through CaMKII pathway to influence periodontal tissue destruction in early periodontitis

Xenogenous implanted dental follicle stem cells promote periodontal regeneration through inducing the N2 phenotype of neutrophils

BACKGROUND

Periodontal tissue loss is the main reason for tooth mobility and loss caused by periodontal disease. Dental follicle stem cells (DFSCs) have significant therapeutic potential in periodontal regeneration, which maybe mainly depends on their potent immunomodulatory capacity. Consequently, this study aims to elucidate the impact of implanted xenogenous DFSCs on innate immune responses during early and late stages in the periodontal defect repair period.

METHODS

To trace and investigate the immunomodulation mechanisms of DFSCs in vivo, DFSCs were engineered (E-DFSCs) using lentiviral vectors expressing CD63-enhanced green fluorescent protein (CD63-EGFP) and β-Actin-mCherry protein (ACTB-mCherry) to exhibit green and red fluorescence. The biological characteristics and functions of E-DFSCs were verified by proliferation, differentiation, and co-culture experiments in vitro. In vivo, the periodontal regeneration capacity of E-DFSCs was detected by implantation of murine periodontal defect model, and the response of innate immune cells was detected at the 1st, 3rd, and 5th days (early stage) and 4th week (late stage) after implantation.

RESULTS

In vitro assessments showed that E-DFSCs retain similar properties to their non-engineered counterparts but exhibit enhanced macrophage immunomodulation capability. In mice models, four-week micro-CT and histological evaluations indicated that E-DFSCs have equivalent efficiency to DFSCs in periodontal defect regeneration. At the early stage of repair in mice periodontal defect, fluorescence tracking showed that implanted E-DFSCs might primarily activate endogenous cells through direct contact and indirect actions, and most of these cells are myeloperoxidase-positive neutrophils. Additionally, compared with the control group, the neutrophilic infiltration and conversion of N2-type were significantly increased in the E-DFSC group. At the late stage of defect regeneration, more M2-type macrophages, fewer TRAP + osteoclasts, and an upregulated OPG/RANKL ratio were detected in the E-DFSC group compared to the control group, which indicated that immune balance tilts towards healing and bone formation.

CONCLUSION

The xenogenous implanted DFSCs can induce the N2 phenotype of neutrophils in the early stage, which can activate the innate immune mechanism of the host to promote periodontal tissue regeneration.

Mechanisms of tissue degeneration mediated by periostin in spinal degenerative diseases and their implications for pathology and diagnosis: a review

Periostin (POSTN) serves a dual role as both a matricellular protein and an extracellular matrix (ECM) protein and is widely expressed in various tissues and cells. As an ECM protein, POSTN binds to integrin receptors, transduces signals to cells, enabling cell activation. POSTN has been linked with various diseases, including atopic dermatitis, asthma, and the progression of multiple cancers. Recently, its association with orthopedic diseases, such as osteoporosis, osteoarthritis resulting from cartilage destruction, degenerative diseases of the intervertebral disks, and ligament degenerative diseases, has also become apparent. Furthermore, POSTN has been shown to be a valuable biomarker for understanding the pathophysiology of orthopedic diseases. In addition to serum POSTN, synovial fluid POSTN in joints has been reported to be useful as a biomarker. Risk factors for spinal degenerative diseases include aging, mechanical stress, trauma, genetic predisposition, obesity, and metabolic syndrome, but the cause of spinal degenerative diseases (SDDs) remains unclear. Studies on the pathophysiological effects of POSTN may significantly contribute toward the diagnosis and treatment of spinal degenerative diseases. Therefore, in this review, we aim to examine the mechanisms of tissue degeneration caused by mechanical and inflammatory stresses in the bones, cartilage, intervertebral disks, and ligaments, which are crucial components of the spine, with a focus on POSTN.

miR-26a-5p alleviates CFA-induced chronic inflammatory hyperalgesia through Wnt5a/CaMKII/NFAT signaling in mice

BACKGROUND

Inflammation often leads to the occurrence of chronic pain, and many miRNAs have been shown to play a key role in the development of inflammatory pain. However, whether miR-26a-5p relieves pain induced by inflammation and its possible mechanism are still unclear.

METHODS

The complete Freund's adjuvant (CFA)-induced inflammatory pain mouse model was employed. Intrathecal or subcutaneous injection of miR-26a-5p agomir was performed after modeling to study its antinociceptive effect and the comparison of different administration methods. Bioinformatics analysis of miRNAs was performed to study the downstream mechanisms of miR-26a-5p. HE staining, RT-qPCR, Western blotting, and immunofluorescence were used for further validation.

RESULTS

A single intrathecal and subcutaneous injection of miR-26a-5p both reversed mechanical hypersensitivity and thermal latency in the left hind paw of mice with CFA-induced inflammatory pain. HE staining and immunofluorescence studies found that both administrations of miR-26a-5p alleviated inflammation in the periphery and spinal cord. Bioinformatics analysis and dual-luciferase reporter gene analysis identified Wnt5a as a direct downstream target gene of miR-26a-5p. Wnt5a was mainly expressed in neurons and microglia in the spinal cord of mice with inflammatory pain. Intrathecal injection of miR-26a-5p could significantly reduce the expression level of Wnt5a and inhibit the downstream molecules of noncanonical Wnt signaling Camk2/NFAT, inhibiting the release of spinal cord inflammatory factors and alleviating the activation of microglia. In addition, miR-26a-5p could also inhibit lipopolysaccharide (LPS)-stimulated BV2 cell inflammation in vitro through a noncanonical Wnt signaling pathway.

CONCLUSIONS

miR-26a-5p is a promising therapy for CFA-induced inflammatory pain. Both intrathecal and subcutaneous injections provide relief for inflammatory pain. miR-26a-5p regulated noncanonical Wnt signaling to be involved in analgesia partly through antineuroinflammation, suggesting a pain-alleviating effect via noncanonical Wnt signaling pathway in the CFA-induced inflammatory pain model in vivo.

The Multiple Roles of Periostin in Non-Neoplastic Disease

Periostin, identified as a matricellular protein and an ECM protein, plays a central role in non-neoplastic diseases. Periostin and its variants have been considered to be normally involved in the progression of most non-neoplastic diseases, including brain injury, ocular diseases, chronic rhinosinusitis, allergic rhinitis, dental diseases, atopic dermatitis, scleroderma, eosinophilic esophagitis, asthma, cardiovascular diseases, lung diseases, liver diseases, chronic kidney diseases, inflammatory bowel disease, and osteoarthrosis. Periostin interacts with protein receptors and transduces signals primarily through the PI3K/Akt and FAK two channels as well as other pathways to elicit tissue remodeling, fibrosis, inflammation, wound healing, repair, angiogenesis, tissue regeneration, bone formation, barrier, and vascular calcification. This review comprehensively integrates the multiple roles of periostin and its variants in non-neoplastic diseases, proposes the utility of periostin as a biological biomarker, and provides potential drug-developing strategies for targeting periostin.

Chronotherapeutic neuroprotective effect of verapamil against lipopolysaccharide-induced neuroinflammation in mice through modulation of calcium-dependent genes

Background

Neuroinflammation is a major mechanism in neurodegenerative diseases such as Alzheimer’s disease (AD), which is a major healthcare problem. Notwithstanding of ample researches figured out possible molecular mechanisms underlying the pathophysiology of AD, there is no definitive therapeutics that aid in neuroprotection. Therefore, searching for new agents and potential targets is a critical demand. We aimed to investigate the neuroprotective effect of verapamil (VRP) against lipopolysaccharide (LPS)-induced neuroinflammation in mice and whether the time of VRP administration could affect its efficacy.

Methods

Forty male albino mice were used and were divided into normal control, LPS only, morning VRP, and evening VRP. Y-maze and pole climbing test were performed as behavioral tests. Hematoxylin and eosin together with Bielschowsky silver staining were done to visualize neuroinflammation and phosphorylated tau protein (pTAU); respectively. Additionally, the state of mitochondria, the levels of microglia-activation markers, inflammatory cytokines, intracellular Ca2+, pTAU, and Ca2+-dependent genes involving Ca2+/ calmodulin dependent kinase II (CAMKII) isoforms, protein kinase A (PKA), cAMP response element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF), with the level of VRP in the brain tissue were measured.

Results

LPS successfully induced neuroinflammation and hyperphosphorylation of tau protein, which was indicated by elevated levels of microglia markers, inflammatory cytokines, and intracellular Ca2+ with compromised mitochondria and downregulated CAMKII isoforms, PKA, CREB and BDNF. Pretreatment with VRP showed significant enhancement in the architecture of the brain and in the behavioral tests as indicated by the measured parameters. Moreover, morning VRP exhibited better neuroprotective profile compared to the evening therapy.

Conclusions

VRP highlighted a multilevel of neuroprotection through anti-inflammatory activity, Ca2+ blockage, and regulation of Ca2+-dependent genes. Furthermore, chronotherapy of VRP administration should be consider to achieve best therapeutic efficacy.

Graphical Abstract

Inhibition of TRPA1 Ameliorates Periodontitis by Reducing Periodontal Ligament Cell Oxidative Stress and Apoptosis via PERK/eIF2α/ATF-4/CHOP Signal Pathway

Objective

In periodontitis, excessive oxidative stress combined with subsequent apoptosis and cell death further exacerbated periodontium destruction. TRPA1, an important transient receptor potential (TRP) cation channel, may participate in the process. This study is aimed at exploring the role and the novel therapeutic function of TRPA1 in periodontitis.

Methods

Periodontal ligament cells or tissues derived from healthy and periodontitis (PDLCs/Ts and P-PDLCs/Ts) were used to analyze the oxidative and apoptotic levels and TRPA1 expression. TRPA1 inhibitor (HC030031) was administrated in inflammation induced by P. gingivalis lipopolysaccharide (P.g.LPS) to investigate the oxidative and apoptotic levels of PDLCs. The morphology of the endoplasmic reticulum (ER) and mitochondria was identified by transmission electron microscope, and the PERK/eIF2α/ATF-4/CHOP signal pathways were detected. Finally, HC030031 was administered to periodontitis mice to evaluate its effect on apoptotic and oxidative levels in the periodontium and the relieving of periodontitis.

Results

The oxidative, apoptotic levels and TRPA1 expression were higher in P-PDLC/Ts from periodontitis patients and in P.g.LPS-induced inflammatory PDLCs. TRPA1 inhibitor significantly decreased the intracellular calcium, oxidative stress, and apoptosis of inflammatory PDLCs and decreased ER stress by downregulating PERK/eIF2α/ATF-4/CHOP pathways. Meanwhile, the overall calcium ion decrease induced by EGTA also exerted similar antiapoptosis and antioxidative stress functions. In vivo, HC030031 significantly reduced oxidative stress and apoptosis in the gingiva and periodontal ligament, and less periodontium destruction was observed.

Conclusion

TRPA1 was highly related to periodontitis, and TRPA1 inhibitor significantly reduced oxidative and apoptotic levels in inflammatory PDLCs via inhibiting ER stress by downregulating PERK/eIF2α/ATF-4/CHOP pathways. It also reduced the oxidative stress and apoptosis in periodontitis mice thus ameliorating the development of periodontitis.

Exosomes Derived From Human Gingival Mesenchymal Stem Cells Attenuate the Inflammatory Response in Periodontal Ligament Stem Cells

This study aimed to explore the effects of exosomes derived from human gingival mesenchymal stem cells (GMSC-Exo) on the inflammatory response of periodontal ligament stem cells (PDLSCs) in an inflammatory microenvironment in order to restore the regenerative potential of PDLSCs, which promotes periodontal tissue regeneration in patients with periodontitis. Periodontitis is a chronic infectious disease characterized by periodontal tissue inflammation and alveolar bone destruction. PDLSCs are regarded as promising seed cells for restoring periodontal tissue defects because of their ability to regenerate cementum/PDL-like tissue and alveolar bone. However, PDLSCs in the inflammatory environment show significantly attenuated regenerative potential. GMSC-Exo have been reported to have anti-inflammatory and immunosuppressive properties. In this study, we investigated the effects of GMSC-Exo on the inflammatory response of PDLSCs induced by lipopolysaccharides (LPS). LPS was used to simulate the inflammatory microenvironment of periodontitis in vitro. GMSC-Exo were extracted from the culture supernatant of GMSCs by ultracentrifugation. We found that GMSC-Exo attenuated the inflammatory response of PDLSCs induced by LPS. Furthermore, compared to treatment with LPS, treatment with GMSC-Exo attenuated the expression of NF-κB signaling and Wnt5a in LPS-induced PDLSCs. In conclusion, we confirmed that GMSC-Exo could suppress the inflammatory response of PDLSCs by regulating the expression of NF-κB signaling and Wnt5a, which paves the way for the establishment of a therapeutic approach for periodontitis.